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  • 2010-2014
  • 2000-2004  (25)
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  • 1
    Electronic Resource
    Electronic Resource
    The need for speed. II. Myelin in calanoid copepods (2000)
    Springer
    Journal of comparative physiology 186 (2000), S. 347-357 
    Details
    ISSN: 1432-1351
    Keywords: Key words Crustacean ; Sensorimotor ; Ultrastructure ; Multilamellar sheath ; Myelinated axons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Speed of nerve impulse conduction is greatly increased by myelin, a multi-layered membranous sheath surrounding axons. Myelinated axons are ubiquitous among the vertebrates, but relatively rare among invertebrates. Electron microscopy of calanoid copepods using rapid cryofixation techniques revealed the widespread presence of myelinated axons. Myelin sheaths of up to 60 layers were found around both sensory and motor axons of the first antenna and interneurons of the ventral nerve cord. Except at nodes, individual lamellae appeared to be continuous and circular, without seams, as opposed to the spiral structure of vertebrate and annelid myelin. The highly organized myelin was characterized by the complete exclusion of cytoplasm from the intracellular spaces of the cell generating it. In regions of compaction, extracytoplasmic space was also eliminated. Focal or fenestration nodes, rather than circumferential ones, were locally common. Myelin lamellae terminated in stepwise fashion at these nodes, appearing to fuse with the axolemma or adjacent myelin lamellae. As with vertebrate myelin, copepod sheaths are designed to minimize both resistive and capacitive current flow through the internodal membrane, greatly speeding nerve impulse conduction. Copepod myelin differs from that of any other group described, while sharing features of every group.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003590050435
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  • 2
    Electronic Resource
    Electronic Resource
    Immunohistochemical localization of mitogen-activated protein kinase (MAPK) family and morphological changes in rat heart after ischemia-reperfusion injury (2000)
    Springer
    Medical electron microscopy 33 (2000), S. 74-81 
    Details
    ISSN: 1437-773X
    Keywords: Key words Mitogen-activated protein kinase (MAPK) ; Ischemia reperfusion injury ; Heart ; Ultrastructure ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The mitogen-activated protein kinase (MAPK) family is considered to be activated by stress, but the role of the MAPK family is still unknown in cardiac pathology. In the present study, not only the localization of MAPKs such as the extracellular responsive kinase (ERK), c-jun N-terminal kinase (JNK), and p38 MAPK (p38), but also ultrastructural changes were investigated in the ischemia-reperfusion model of Wistar rats. At 5, 10, 30, 60, and 180 min reperfusion after 30 min ischemia by occluding the coronary artery, the expression of these MAPKs was increased in blood vessels and cardiomyocytes by Western blotting and immunohistochemical methods. In addition, after ischemia reperfusion, various ultrastructural changes such as decreased glycogen granules, mitochondrial swelling, and myolysis were observed in the blood vessels and cardiomyocytes. These results suggest that protein kinases may regulate numerous biological processes, including the regulation of contraction and ion transport.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s007950070005
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  • 3
    Electronic Resource
    Electronic Resource
    An immunohistochemical and ultrastructural study of a follicle-stimulating hormone-secreting gonadotroph adenoma occurring in a 10-year-old girl (2000)
    Springer
    Medical electron microscopy 33 (2000), S. 25-31 
    Details
    ISSN: 1437-773X
    Keywords: Key words Gonadotroph adenoma ; FSH ; Childhood ; Ultrastructure ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Female gonadotroph adenomas with endocrinological symptoms are uncommon. Six cases of such adenomas have been reported in the literature: two were girls who presented with precocious puberty and four were premenopausal women with accompanying multiple ovarian cysts. We describe here a 10-year-old Japanese girl with a gonadotroph macroadenoma and present detailed morphological findings of the tumor. The patient's chief complaints were nausea, abdominal distention, and abdominal pain. Abdominopelvic ultrasonography and magnetic resonance imaging (MRI) revealed bilateral multiple ovarian cysts. Endocrinological assays showed elevated serum follicle-stimulating hormone (FSH) (33.7 mIU/ml) and estradiol (3840 pg/ml). MRI of the head showed a large pituitary tumor. Two transsphenoidal operations and subsequent radiation therapy were performed. Immunohistochemically, more than half the tumor cells were positive for anti-FSH-β monoclonal antibody. Ultrastructurally, the tumor cells exhibited a fairly uniform picture of rounded cells. Their nuclei were slightly irregular and contained heterochromatin, and their cytoplasm contained many round, dense core granules, measuring 140–260 nm in diameter, together with well-developed organelles. An in vitro study showed that the tumor cells in primary culture produced FSH (1089.0 mIU/ml). To our knowledge, this is the first immunohistochemical and ultrastructural study of an FSH-secreting gonadotroph adenoma occurring in childhood.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s007950000004
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  • 4
    Electronic Resource
    Electronic Resource
    Ultrastructural evaluation of apoptosis induced by Helicobacter pylori infection in human gastric mucosa: novel remarks on lamina propria mucosae (2000)
    Springer
    Medical electron microscopy 33 (2000), S. 82-88 
    Details
    ISSN: 1437-773X
    Keywords: Key words Apoptosis ; Helicobacter pylori ; Fibroblasts ; Smooth muscle cells ; Ultrastructure ; Gastroduodenal ulcer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract It has been considered that Helicobacter pylori (H. pylori) infection is a major cause of human gastritis and gastroduodenal ulcers (G-DU). Many investigations of the relationship between H. pylori and apoptosis have been reported recently. However, these studies focused mostly on epithelium, using the TUNEL method. In the present study, we evaluated by electron microscopy the occurrence of apoptosis in the mesenchymal cells of lamina propria mucosae infected with H. pylori. Gastric biopsy specimens from 37 H. pylori-infected G-DU patients and 8 noninfected volunteers were examined with both light and electron microscopy and analyzed by the TUNEL method. The TUNEL method showed no significant difference between H. pylori-infected and noninfected cases. In contrast, electron microscopy revealed significant numbers of apototic fibroblasts and smooth muscle cells in H. pylori-infected lamina propria mucosae, with a diminished number of collagen fibers in surrounding areas. These areas showed edematous changes histopathologically. These results indicated that H. pylori infection induces apoptosis of fibroblasts and smooth muscle cells in lamina propria, with decrease in the numbers of collagen fibers, suggesting that these alterations may be affected by exaggerate acid secretion, decrease mucus protecting factors, and result in ulcer formation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s007950070006
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  • 5
    Electronic Resource
    Electronic Resource
    Ciliogenesis and ciliary abnormalities (2000)
    Springer
    Medical electron microscopy 33 (2000), S. 109-114 
    Details
    ISSN: 1437-773X
    Keywords: Key words Ciliogenesis ; Ciliated cell ; Abnormal cilia ; Basal body ; Ultrastructure ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Cilia are motile processes extending from the basal bodies, playing important roles in the mucociliary clearance in the respiratory tract and the transport of the ovum from the ovary to the uterus in mammals. Ciliogenesis is divided into four stages: (1) duplication of centrioles; (2) migration of centrioles to the apical cell surface to become basal bodies; (3) elongation of cilia containing the axoneme; and (4) formation of accessory structures of basal bodies. The orderly course of ciliogenesis appears to be disturbed by various internal and external factors and, as a result, various unusual forms of the ciliary apparatus develop in the cell. Inhibition of basal body migration results in development of intracytoplasmic axonemes, cilia within periciliary sheaths, and intracellular ciliated cysts. Swollen cilia and the bulging type of compound cilia are formed during ciliary budding and elongation. This review also discusses the origin, composition, and function of the centriolar precursor structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s007950000009
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  • 6
    Electronic Resource
    Electronic Resource
    Abnormal elastic system fibers in fibrotic human liver (2000)
    Springer
    Medical electron microscopy 33 (2000), S. 135-142 
    Details
    ISSN: 1437-773X
    Keywords: Key words Elastic system fiber ; Ultrastructure ; Fibrotic human liver ; Oxytalan fiber ; Elaunin fiber
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The network of elastic system fibers in human fibrotic liver was investigated by histological methods, immunohistochemical staining, and electron microscopy. Type III collagen was seen not only in regions of portal fibrosis but also in the sinusoidal wall. However, elastic system fibers were not found in the Disse space of the sinusoidal wall. Elastic system fibers including oxytalan, elaunin, and elastic fibers were found successively in the course of elastogenesis. A few normal oxytalan fibers and abnormal oxytalan fibers were observed in the periportal tracts. Few normal elaunin and abnormal elaunin fibers were observed in regions of portal fibrosis but not in the surrounding margin. Elastic fibers, only in scarce amounts, were observed around the portal veins in the case of chronic active hepatitis but not in acute hepatitis. Abnormal oxytalan fibers were seen as a bundle of wavelike microfibrils and had an irregular arrangement. Abnormal elaunin fibers were not associated with bundles of microfibrils. Abnormal elaunin fibers in large amounts were found interspersed with spiraled collagen, which most likely indicates that the oxytalan fibers degenerated in the course of elastogenesis. Thus, in a fibrotic liver it is possible that synthesis of normal elaunin and elastic fibers does not occur or that the quantity of such fibers synthesized may be small because of the effect of the degenerated oxytalan fibers. As a characteristic of liver fibrosis, the composition of abnormal elastic system fibers and spiraled collagen differs from that in other fibrotic organs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s007950000013
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  • 7
    Electronic Resource
    Electronic Resource
    Adenoid basal carcinoma of the uterine cervix: a case report with ultrastructural findings (2000)
    Springer
    Medical electron microscopy 33 (2000), S. 241-245 
    Details
    ISSN: 1437-773X
    Keywords: Key words Adenoid basal carcinoma ; Uterine cervix ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Adenoid basal carcinoma of the uterine cervix is a rare tumor with a favorable prognosis. A case of adenoid basal carcinoma (ABC) of the uterine cervix was studied using light and electron microscopy. The patient was a 74-year-old Japanese woman who had undergone hysterectomy due to cervical intraepithelial neoplasia 3. Incidentally, ABC was found in the resected uterus. The tumor cells made small nests and infiltrated the cervical portion of the uterus. In the nests, glands, cribriform patterns with glandlike structures, and squamous differentiation were seen. Immunohistochemically, the glandlike structures were positive for laminin and type IV collagen. Ultrastructurally, the tumor cells had irregular nuclei, scanty cytoplasm, and cribriform patterns in which glandlike structures were covered with basal lamina. No myoepithelial differentiation of the tumor cells was seen. These findings suggest a similarity between adenoid basal carcinomas and adenoid cystic carcinomas. Furthermore, both tumors are considered to originate in the reserve cells of the uterine cervix. Because their outcomes are different, they should be distinguished from each other.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s007950000024
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  • 8
    Electronic Resource
    Electronic Resource
    Variation among giant rice bodies: report of four cases and their clinicopathological features (2000)
    Springer
    Skeletal radiology 29 (2000), S. 525-529 
    Details
    ISSN: 1432-2161
    Keywords: Key words Giant rice body ; Ultrastructure ; Immunohistochemistry ; Histogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Objective: To report four cases of rice bodies (RBs) showing remarkable size variations and discuss their pathogenesis. Design and patients: Based on analysis of the clinical data, we speculate on the pathogenesis of RBs using immunohistochemical and ultrastructural methods. The patients comprised three men and one woman, three with RBs in the subacromial bursae and one in the wrist synovial sheath, aged 28 (woman), 44, 50 and 81 (wrist) years, respectively. Results: There were no particular differences in clinical data among the patients. T2-weighted MR imaging was very useful for diagnosis of the RBs, allowing their clear delineation from the bursal fluid. The RBs consisted of a layered protein- aceous substance with vague targetoid cut surfaces. Much fibrin and a lesser amount of collagen fibers were recognized together with various mononuclear cells, which were few in number and predominantly T cells. The bursae and synovial sheath had multiple fibrinoid spheroids at the luminal surface. Conclusion: Fibrinoid nodular deposits probably became detached, forming the nuclei of RBs and growing to a giant RB 65 mm in diameter.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002560000258
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  • 9
    Electronic Resource
    Electronic Resource
    Ultrastructure and molecular histology of rabbit hind-limb collateral artery growth (arteriogenesis) (2000)
    Springer
    Virchows Archiv 436 (2000), S. 257-270 
    Details
    ISSN: 1432-2307
    Keywords: Key words Arteriogenesis ; Collateral vessels ; Ultrastructure ; Cell adhesion molecules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Previous studies in the canine heart had shown that the growth of collateral arteries occurs via proliferative enlargement of pre-existing arteriolar connections (arteriogenesis). In the present study, we investigated the ultrastructure and molecular histology of growing and remodeling collateral arteries that develop after femoral artery occlusion in rabbits as a function of time from 2 h to 240 days after occlusion. Pre-existent arteriolar collaterals had a diameter of about 50 µm. They consisted of one to two layers of smooth muscle cells (SMCs) and were morphologically indistinguishable from normal arterioles. The stages of arteriogenesis consisted of arteriolar thinning, followed by transformation of SMCs from the contractile- into the proliferative- and synthetic phenotype. Endothelial cells (ECs) and SMCs proliferated, and SMCs migrated and formed a neo-intima. Intercellular adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1) showed early upregulation in ECs, which was accompanied by accumulation of blood-derived macrophages. Mitosis of ECs and SMCs started about 24 h after occlusion, whereas adhesion molecule expression and monocyte adhesion occurred as early as 12 h after occlusion, suggesting a role of monocytes in vascular cell proliferation. Treatment of rabbits with the pro-inflammatory cytokine MCP-1 increased monocyte adhesion and accelerated vascular remodeling. In vitro shear-stress experiments in cultured ECs revealed an increased phosphorylation of the focal contacts after 30 min and induction of ICAM-1 and VCAM-1 expression between 2 h and 6 h after shear onset, suggesting that shear stress may be the initiating event. We conclude that the process of arteriogenesis, which leads to the positive remodeling of an arteriole into an artery up to 12 times its original size, can be modified by modulators of inflammation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004280050039
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  • 10
    Electronic Resource
    Electronic Resource
    Ganglioglioma with a tanycytic ependymoma as the glial component (2000)
    Springer
    Acta neuropathologica 99 (2000), S. 310-316 
    Details
    ISSN: 1432-0533
    Keywords: Key words Ganglioglioma ; Ependymoma (tanycytic variant) ; Neurofibrillary tangle ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We studied a cystic ganglioglioma (GG) located in the right frontal lobe of the brain. Interestingly, the fibrillary spindle glial cells were often arranged in a fascicular pattern, and the generally uniform, round-to-oval delicate nuclei appeared to resemble those of ependymoma; and the neoplastic neurons often contained neurofibrillary tangles (NFTs). The glial component was positive for glial fibrillary acidic protein and occasionally contained granular or microvesicular structures positive for epithelial membrane antigen. Ultrastructural investigation revealed that the glial cells were ependymal in nature; intracytoplasmic lumina and intercellular microrosettes lined with cilia and microvilli, as well as long zonulae adherentes, were evident. In addition, chromogranin A-positive granular staining, neurosecretory-granule-like structures, and parallel arrays of microtubules were sometimes associated with the blood vessels. We considered the present case to be an unusual example of GG with an ependymoma, more precisely a tanycytic ependymoma, as the glial component; to our knowledge, the existence of ependymoma as the main glial component of this particular tumor has not been described before. The occurrence of NFTs, which has been reported in several cases of GG, was an additional, unusual feature.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00007443
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  • 11
    Electronic Resource
    Electronic Resource
    Eosinophilic inclusions in ependymoma represent microlumina: a light and electron microscopic study (2000)
    Springer
    Acta neuropathologica 99 (2000), S. 214-218 
    Details
    ISSN: 1432-0533
    Keywords: Key words Eosinophilic inclusion body ; Inclusion ¶body ; Ependymoma ; Microlumina ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A study was undertaken to determine the pathological significance of previously unrecognized intracytoplasmic eosinophilic inclusions (IEIs) in ependymoma. The study group consisted of 58 ependymomas, all of which were pathologically characterized and graded according to the 1993 WHO classification. Electron microscopic studies were performed in 16 cases. The study showed that 33 (57%) ependymomas had IEIs and that in 8 cases these were abundant. Round and eosinophilic, their sizes varied from 10 μm to a tiny dot. Similar eosinophilic bodies were also observed between tumor cells. The inclusions were weakly PAS positive. On immunostains, IEIs were frequently positive for glial fibrillary acidic protein, less often for S-100 protein, and for epithelial membrane protein and CAM 5.2. They were negative for AE1/AE3, carcinoembryonic antigen and Ber-EP4. Ultrastructurally, IEIs represented intracytoplasmic lumens containing microvilli and cilia. These microlumina also frequently contained granulo-tubular materials. With reference to tumor subtypes, IEIs occurred most frequently in ordinary and clear cell ependymomas. IEIs were also present in 4 of 6 anaplastic ependymomas studied. In conclusion, IEIs represent microlumina and occur in more than a half of ependymomas including malignant examples. Their finding is a helpful diagnostic feature of ependymoma.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00007427
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  • 12
    Electronic Resource
    Electronic Resource
    Ultrastructure of the normal adult human female prostate gland (Skene’s gland) (2000)
    Springer
    Anatomy and embryology 201 (2000), S. 51-61 
    Details
    ISSN: 1432-0568
    Keywords: Key words Female prostate (Skene gland) ; Ultrastructure ; Secretory (luminal) cells ; Basal (reserve) cells ; Intermediary cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The predominant cells of female prostatic glands lining their lumen were found to be tall cylindrical secretory cells with short stubby microvilli, protuberances of the apical cytoplasm, and with bleb formation. Abundant secretory vacuoles and granules, rough endoplasmic reticulum, developed Golgi complexes and numerous mitochondria are characteristic of their active secretory configuration with apocrine (apical blebs) and merocrine (secretory vacuoles and granules) type of secretion. Basal (reserve) cells were seen to be located between the secretory (luminal) cells and the basement membrane. Their ground cytoplasm is dense with rough endoplasmic reticulum and mitochondria. Their nuclei, unlike those of secretory cells, possess more peripheral condensed chromatin, denser dispersed chromatin and sporadic nucleoli. Besides the two basic types of mature prostatic cells intermediary cells were also seen, located between the basal and secretory cells or in their close vicinity. Their cytoplasm exhibits numerous profiles of rough endoplasmic reticulum and free ribosomes. Secretory vacuoles and granules were mostly practically absent (type 1 intermediary cells) so that they resembled basal (reserve) cells. In some of them, however, as in secretory cells, such secretory elements do gradually appear (type 2 intermediary cells). The finding of intermediary cells in the lining of prostatic glands supports the role of basal (reserve) cells in the renewal of cells in glands of the female prostate. The first ultrastructural analysis of the normal female prostate performed by transmission electron microscopy showed that, as in the postpubertal male, the prostatic glands in the adult female display mature secretory and basal cells. The results of the presented study further corroborate the contemporary concept of the female prostate as a functional genitourinary organ.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/
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  • 13
    Electronic Resource
    Electronic Resource
    Microglial cells are the driving force in fibrillar plaque formation, whereas astrocytes are a leading factor in plaque degradation (2000)
    Springer
    Acta neuropathologica 100 (2000), S. 356-364 
    Details
    ISSN: 1432-0533
    Keywords: Key words Alzheimer disease ; Fibrillar amyloid-β ; Astrocytes ; Microglial cell ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Ultrastructural three-dimensional reconstruction of human classical plaques in different stages of development shows that microglial cells are the major factor driving plaque formation by fibrillar amyloid-β (Aβ) deposition. The amount of fibrillar Aβ released by microglial cells and the area of direct contact between amyloid and neuron determine the extent of dystrophic changes in neuronal processes and synapses. The volume of hypertrophic astrocytic processes separating fibrillar amyloid from neuron is a measure of the protective activation of astrocytes. On the bases of the volume of amyloid star, microglial cells, dystrophic neurites, and hypertrophic astrocytic processes, and spatial relationships between plaque components, three stages in classical plaque development have been distinguished: early, mature, and late. In early plaque, the leading pathology is fibrillar Aβ deposition by microglial cells with amyloid star formation. The mature plaque is characterized by a balance between amyloid production, neuronal dystrophy, and astrocyte hypertrophy. In late classical plaque, microglial cells retract and expose neuropil on direct contact with amyloid star, enhancing both dystrophic changes in neurons and hypertrophic changes in astrocytes. In late plaques, activation of astrocytes predominates. They degrade amyloid star and peripheral amyloid wisps. The effect of these changes is classical plaque degradation to fibrillar primitive and finally to nonfibrillar, diffuse-like plaques.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010000199
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  • 14
    Electronic Resource
    Electronic Resource
    GM1-gangliosidosis in a cross-bred dog confirmed by detection of GM1-ganglioside using electrospray ionisation-tandem mass spectrometry (2000)
    Springer
    Acta neuropathologica 100 (2000), S. 409-414 
    Details
    ISSN: 1432-0533
    Keywords: Key words GM1-gangliosidosis ; Ultrastructure ; Electrospray ionisation tandem mass spectrometry ; Diagnosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The post-mortem diagnosis of lysosomal storage diseases can be confounded by the unavailability of suitable material. Here we report the diagnosis of GM1-gangliosidosis in a cross-bred dog, from which only formalin-fixed brain was available, by a combination of electron microscopy and the detection of elevated levels of GM1-ganglioside within the tissue using the novel technique of electrospray ionisation tandem mass spectrometry. Electron microscopic examination of ultrathin sections of resin-embedded tissue revealed cytoplasmic inclusions (membranous cytoplasmic and zebra bodies) in brain stem and cerebellar neurons that were characteristic of a gangliosidosis. Glycolipids were extracted from the fixed tissue and analysed by tandem mass spectrometry. Two major ions were detected, which corresponded to GM1 (d18:1–C18:0) and GM1 (d20:1–C18:0). Their identity was confirmed by comparison of their fragmentation patterns with those of authentic standards. The concentration of GM1 was approximately sixfold higher on a wet weight basis than in the brain of a normal control dog, confirming the diagnosis of GM1-gangliosidosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010000187
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  • 15
    Electronic Resource
    Electronic Resource
    Light and electron microscopic examination of endothelial cells from bovine retinal vessels in long-term cultures (2000)
    Springer
    Virchows Archiv 436 (2000), S. 249-256 
    Details
    ISSN: 1432-2307
    Keywords: Key words Endothelial cells ; Cell culture ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The aim of the present work was to examine and compare the ultrastructure of bovine retinal endothelial cells (BRECs) in vitro during several passages in a medium selective for endothelial cells. The identity of the endothelial cells was confirmed immunohistochemically, up to the tenth passage. Changes in their ultrastructure in comparison to endothelial cells in vivo occurred at the onset of culturing and not progressively with repeated passages. The cultured BRECs show high metabolic activity in all passages. While retaining their identity as endothelial cells, they modify their lipid metabolism, so that lipids are stored. This change in lipid metabolism was induced by the medium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004280050038
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  • 16
    Electronic Resource
    Electronic Resource
    The ultrastructure of photoreceptor cells in the pineal organ of the blind cave salamander, Proteus anguinus (Amphibia, Urodela) (2000)
    Springer
    Pflügers Archiv 439 (2000), S. r175 
    Details
    ISSN: 1432-2013
    Keywords: Key words Pineal organ ; Photoreceptor cells ; Ultrastructure ; Proteus anguinus ; Regressive evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We studied ultrastructure of the photoreceptor cells in the pineal organ of blind, depigmented, neotenic cave salamander, Proteus anguinus. Unlike in epigean vertebrates the outer segments of most photoreceptor cells consists of concentrically arranged lamellae, however; in few cells, the outer segments contain 7-9 plasma membrane disks. In both types of photoreceptor cells the outer segments enclose lumps of vesicles of different sizes. The photoreceptor cells of Proteus anguinus are similar to those in other cavernicolous fish species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004240000136
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  • 17
    Electronic Resource
    Electronic Resource
    Atypical morphological characteristics and surface antigen expression of Burkholderia pseudomallei in naturally infected human synovial tissues (2000)
    Springer
    Modern rheumatology 10 (2000), S. 129-136 
    Details
    ISSN: 1439-7609
    Keywords: Key words Septic arthritis ; Surface antigens ; Ultrastructure ; Burkholderia pseudomallei ; IEM
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Burkholderia pseudomallei is the causative agent of melioidosis, a disease that frequently runs a protracted course and is very difficult to eradicate. The mechanisms that this organism uses to escape from host defense mechanisms and antibiotics are not well understood. The aim of the study was to compare the morphological characteristics and surface antigen expression of B. pseudomallei in naturally infected human synovial tissues with the characteristics of bacteria grown in culture media. Immunoelectron microscopic study was performed in four synovial biopsies taken from four B. pseudomallei septic arthritis patients. Colonies of pathogenic B. pseudomallei collected from culture media were used as positive controls. Polyclonal antibody to whole cell B. pseudomallei was used as a primary antibody. Complete bacteria-like particles were demonstrated both extracellularly and intracellularly in all four synovial specimens. The intracytoplasmic location of B. pseudomallei and mononuclear phagosome containing microcolony-like structures were demonstrated. B. pseudomallei found in the synovial membrane samples were mostly atypical, with fewer cytoplasmic electron lucent granules. Immunogold staining of bacterial surface antigens was weaker than staining of positive controls. We demonstrated atypical forms of B. pseudomallei and evidence for suppression of its surface antigens in naturally infected human synovial tissues. This adaptation may help bacteria to survive despite host immune surveillance and treatment with antibiotics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s101650070019
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  • 18
    Electronic Resource
    Electronic Resource
    Glomus claroideum forms an arbuscular mycorrhiza-like symbiosis with the hornwort Anthoceros punctatus (2000)
    Springer
    Mycorrhiza 10 (2000), S. 15-21 
    Details
    ISSN: 1432-1890
    Keywords: Anthoceros punctatus ; Arbuscular mycorrhiza ; Bryophytes ; Glomus ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Glomus claroideum (Schenck & Smith emend. Walker & Vestberg) were investigated for ability to form arbuscular mycorrhiza-like symbioses with the hornwort Anthoceros punctatus (L.). Spores were transferred to a cellulose acetate filter on water agar and a small portion of an Anthoceros thallus was placed directly upon the spores. Light-microscope observations 20 days after inoculation revealed branched hyphae growing within the thallus. After 45 days, arbuscules and vesicles were studied by light- and electron-microscopy. After 60 days in water agar culture, the colonised Anthoceros thalli were transferred to a low-nutrient medium agar. Hyphae spread in the agar and newly formed spores were observed 5 weeks after the transfer. After 4 months, about 1000 spores were formed in each Petri dish. This is the first report of an experimentally established arbuscular mycorrhiza-like symbiosis between an identified fungus belonging to the Glomales and a bryophyte.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s005720050282
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  • 19
    Electronic Resource
    Electronic Resource
    Chronic effects of streptozotocin-induced diabetes on the ultrastructure of rat ventricular and papillary muscle (2000)
    Springer
    Acta diabetologica 37 (2000), S. 119-124 
    Details
    ISSN: 1432-5233
    Keywords: Key words Streptozotocin ; Diabetes ; Ventricular myocyte ; Cardiac muscle ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Contractile dysfunctions have been demonstrated in different experimental models of diabetes which have similar characteristics to many of the abnormalities found in the clinical setting. Administration of streptozotocin (STZ) to young adult rats induces β-cell necrosis of the pancreas which gives rise to hypoinsulinaemia and hyperglycaemia, features which are also seen in untreated type 1 clinical diabetes. We have investigated the chronic effects of STZ-induced diabetes on contraction in rat ventricular myocytes and ultrastructure of cardiac muscle. Diabetes was induced in male Wistar rats (230–270 g) with a single injection of STZ (60 mg kg−1). At 2 and 10 months after STZ treatment, the amplitude of contraction was larger in diabetic compared to control myocytes. Time to peak contraction was significantly longer at 2 months but appeared to normalise at 10 months after STZ treatment. In contrast, time to half relaxation of contraction was not significantly different after 2 months but was significantly reduced at 10 months after STZ treatment compared to control. Transmission electron microscope examination of cardiac muscle showed that the ultrastructure of cardiac muscle, especially structures associated with contraction, were not greatly altered after STZ treatment. Sarcomere lengths were not significantly different in papillary or ventricular muscle at 4 or 8 months after STZ treatment compared to control. Our data provide evidence that morphological defects in contractile myofilaments and associated structures cannot explain contractile dysfunctions seen in ventricular myocytes from STZ-treated animals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s005920070013
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  • 20
    Electronic Resource
    Electronic Resource
    Effect of osmotic stress on tolerance of air-drying and cryopreservation ofArabidopsis thaliana suspension cells (2000)
    Springer
    Protoplasma 214 (2000), S. 227-243 
    Details
    ISSN: 1615-6102
    Keywords: Arabidopsis thaliana ; Cryopreservation ; Dehydration ; Thermal analysis ; Sucrose ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Arabidopsis thaliana suspension cells were preserved in liquid nitrogen for over three years, using embedding of cells in calcium-alginate prior to subculture in sucrose-enriched medium, air-drying, and direct quenching in liquid nitrogen. Survival of cells reached 34%, yielding regrowth at the surface of all cryopreserved beads in less than 7 days. Following pretreatment and dehydration, the water content dropped from 2300% to 34% with respect to dry weight. Differential scanning calorimetry showed that glass transition occurred on cooling, followed by a slight crystallization event on rewarming. The survival of cells was independent of the cooling rate. The tolerance of the acute dehydration step increased progressively with sucrose pretreatment duration, indicating the requirement for adaptative cellular alterations. Ultrastructural studies revealed several changes in cells after sucrose pretreatment prolonged from 1 to 7 days: reversal of the initially plasmolyzed state, microvacuolation, numerous autophagic structures, scarcity of ribosomes, increase in number and size of starch grains. No cell division seemed to occur during this period. After air-drying and after a freeze-thaw cycle, followed by 24 h rehydration, regenerating cells had recovered a high level of ultrastructural organization and contained numerous polysomes suggesting an intense metabolic activity. Trehalose, a cryoprotective disaccharide not considered to be a metabolic substrate, yielded only 70% regrowth after freezing. Biochemical analysis showed that soluble sugars accumulated during the pretreatment, essentially sucrose or trehalose; the monosaccharide content also increased. In the light of these results, the action of sucrose in inducing freezing tolerance is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01279067
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  • 21
    Electronic Resource
    Electronic Resource
    Ultrastructure and anatomy of nematode-induced syncytia in roots of susceptible and resistant sugar beet (2000)
    Springer
    Protoplasma 211 (2000), S. 39-50 
    Details
    ISSN: 1615-6102
    Keywords: Beta vulgaris ; Cyst nematodes ; Histology ; Resistance mechanism ; Syncytium ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Using susceptible and resistant sugar beet lines, comparative analyses of root histology and ultrastructure were made during invasion by nematodes and the induction and formation of specific feeding structures (syncytia).The resistant line carried the resistance geneHs1pro−1.Nematodes were able to invade and induce functional syncytia in roots of resistant and susceptible lines. However, syncytia in resistant roots were smaller and less hypertrophied. The vacuolar system of syncytia in susceptible plants contained many small vacuoles. In resistant plants vacuoles were larger but less numerous. Smooth endoplasmic reticulum prevailed in syncytial protoplasts of susceptible plants, whereas almost only rough endoplasmic reticulum occurred in syncytia in resistant plants. The most conspicuous and hitherto undescribed trait of syncytia in resistant roots was the initial appearance of loose, and later compact, aggregations of the endomembrane system which composed most of the endoplasmicreticulum system of syncytia at later stages. Syncytia in resistant plants usually degraded before the nematodes reached their adult stage. The appearance of membrane aggregations and the other resistance-specific features are discussed in relation to their possible effects on syncytium function and role in nematode resistance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01279898
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  • 22
    Electronic Resource
    Electronic Resource
    Structural changes during early embryogenesis in wheat pollen (2000)
    Springer
    Protoplasma 211 (2000), S. 94-102 
    Details
    ISSN: 1615-6102
    Keywords: Androgenesis ; Embryogenesis ; Microspore culture ; Pollen ; Ultrastructure ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have made a detailed cytological examination of the development of wheat embryoids, monitoring their initial divisions from two to ten cells by both light and electron microscopy. According to our observations the first embryogenic division is symmetrical. After the androgenesis induction treatment, there is a decrease in ribosome population with cells that have inactive nucleoli made up almost exclusively of a dense fibrillar component. This population is restored after initial embryogenic divisions. During the initial divisions the embryogenic pollen grains do not appear to change in size and the pollen wall remains intact. The exine undergoes no modification but the intine thickens, and we have observed that the thickness of the intine can be used as a cytological marker of androgenesis. The walls separating the cells obtained after embryogenic division contained numerous plasmodesmata. The beginnings of embryo polarization and cell differentiation could be made out in the very early pollen embryoids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01279902
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  • 23
    Electronic Resource
    Electronic Resource
    Effects of glutathione on thiol redox systems, chromosomal aberrations, and the ultrastructure of meristematic root cells ofPicea abies (L.) Karst. (2000)
    Springer
    Protoplasma 212 (2000), S. 227-235 
    Details
    ISSN: 1615-6102
    Keywords: Glutathione ; Root ; Chromosomal aberration ; Ultrastructure ; Picea abies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Young spruce seedlings (Picea abies [L.] Karst.) grown in hydroponic culture were exposed to three different concentrations (50,100, and 500 μM) of reduced glutathione for 24 h. These physiologically relevant concentrations of glutathione had a multiple effect on the investigated tissue. Feeding of glutathione to roots increased the concentrations of thiols (glutathione, cysteine, and γ-glutamyl-cysteine) in roots, decreased the rate of cell divisions, induced mitotic abnormalities, and affected the cell ultrastructure. Electron micrographs showed effects such as advanced vacuolation, dilated rough-endoplasmic-reticulum cisternae, and separations of the plasma membrane from the cell wall.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01282923
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  • 24
    Electronic Resource
    Electronic Resource
    Morphological aspects of the neuronal ceroid lipofuscinoses (2000)
    Springer
    Neurological sciences 21 (2000), S. S27 
    Details
    ISSN: 1590-3478
    Keywords: Key words Neuronal ceroid lipofuscinoses ; Lipopigments ; Ultrastructure ; Classification ; Genes ; Neuronal loss
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Morphological aspects of the neuronal ceroid lipofuscinoses (NCL) encompass two main features: loss of nerve cells and accumulation of autofluorescent lipopigments within cellular compartments. The former requires histology and morphometry for assessment, while the latter necessitates fluorescence microscopy, electron microscopy, and immunohistochemistry. Accumulation of lipopigments is widespread throughout the central nervous system and extracerebrally. The latter feature enables diagnosis of NCL and its clinical subtype. Loss of neurons is most pronounced in cerebral and cerebellar cortices, in early childhood forms. In subcortical grey matter and in later-onset forms, juvenile and adult NCL, reduction in neurons and possible preceding dendritic pathology may only correctly be ascertained by age-matched, controlled morphometric investigations which, to date, have not yet completely assessed subcortical neuronal damage. Presently, clinical and morphological evaluations are mandatory for genetic analysis, genetic counselling, and prenatal diagnosis, the latter often being based on combined genetic and morphological studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100720070037
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  • 25
    Electronic Resource
    Electronic Resource
    A cellular variant of supratentorial hemangioblastoma (2000)
    Springer
    Brain tumor pathology 17 (2000), S. 15-19 
    Details
    ISSN: 1861-387X
    Keywords: Hemangioblastoma ; Supratentorial tumor ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Supratentorial hemangioblastomas are rarely seen, especially in children and adolescents. We report the case of a 17-year-old male with supratentorial hemangioblastoma. Neuroimaging demonstrated a cystic lesion within the right parietal lobe. Systemic examination revealed no abnormality. The lesion was not attached to the dura and was not associated with von Hippel-Lindau disease. It was very difficult to confirm the final diagnosis of this case, in spite of extensive examination by light microscopy, immunohistochemical studies, and electron microscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02478913
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  • 26
    Electronic Resource
    Electronic Resource
    The process of ultrastructural changes from nuclei to apoptotic body (1998)
    Springer
    Virchows Archiv 433 (1998), S. 443-447 
    Details
    ISSN: 1432-2307
    Keywords: Key words Apoptosis ; Crescent-shaped spaces ; Ultrastructure ; Nivalenol ; Thymus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  There have been many reports on the formation of apoptotic bodies, but little is known about the cellular pathological processes and the morphological changes involved. We induced apoptotic cell death by administering nivalenol (NIV), a trichothecene mycotoxin produced by Fusarium species, and investigated the ultrastructural process of formation of apoptotic bodies. The thymus was examined by electron microscopy 6, 12, and 18 h after administration. Apoptotic cell death was induced in the thymus of NIV-treated mice. The nuclei became invaginated and pinched off to give fragments, and crescent-shaped spaces (CSS) were found around the nuclear envelopes of these cells at quite an early stage. In some of these spaces, myelin figures were observed. We divided the process of formation into four stages and characterized each of them. These are easily recognized in morphological stages and are also useful for clarifying the apoptotic mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004280050272
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  • 27
    Electronic Resource
    Electronic Resource
    Late-onset progressive spinocerebellar degeneration in Brittany Spaniel dogs (1998)
    Springer
    Acta neuropathologica 96 (1998), S. 97-101 
    Details
    ISSN: 1432-0533
    Keywords: Key words Brittany Spaniel dog ; Immunocytochemistry ; Purkinje cell ; Spinocerebellar degeneration ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Eight Brittany Spaniel dogs, seven females and one male, between 7 and 14 years old presented with clinical neurological signs of spinocerebellar disease of about 6 months to 4 years duration. Clinically the dogs had a dramatic forward “saluting” movement of the thoracic limbs, hypermetria of the pelvic limbs, cerebellar ataxia and intention tremors. Terminally, dogs crawled in a crouched thoracic posture with neck extension. Lesions were confined to cerebellum, medulla oblongata and spinal cord. The most severe lesion was diffuse Purkinje cell loss with massive neurofilament accumulation in degenerating cells. There was some bilateral neuronal degeneration in the dorsal horns of the spinal cord and in the gracilis and cuneate nuclei. There was bilateral sporadic axonal degeneration in the dorsal columns and lateral and ventromedial areas of the spinal cord. The etiology of this syndrome was not determined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050865
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  • 28
    Electronic Resource
    Electronic Resource
    Characterizations of heterotopic neurons in the spinal cord of amyotrophic lateral sclerosis patients (1998)
    Springer
    Acta neuropathologica 95 (1998), S. 367-372 
    Details
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Heterotopic neuron ; Alpha motor neuron ; Immunocytochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This report concerns a comparative immunocytochemical, ultrastructural and morphometric investigation on heterotopic neurons in the white matter of the spinal cords of 19 patients with amyotrophic lateral sclerosis (ALS) and 18 age-matched neurologically normal individuals. The study revealed that the heterotopic neurons were scattered in the white matter, often adjacent to gray matter, that they immunoreacted with the antibody to synaptophysin, and that there were synaptic apparatuses on the surface of their somata and their neuronal processes. Bunina bodies and ubiquitin-positive inclusions such as Lewy body-like inclusions and skein-like inclusions, characteristic of anterior horn neurons of ALS, were present in the cytoplasm of the patients’ heterotopic neurons in the anterior or lateral column of the white matter. These findings suggest that heterotopic neurons in the anterior or lateral column have the characteristics of alpha motor neurons. The average number of heterotopic neurons observed in ALS patients was generally less than in normal subjects. This reduction was correlated with the severity of neuronal loss. The heterotopic neurons in ALS were less susceptible to the degenerative process as compared with spinal cord anterior horn cells. We assume that in this disease the heterotopic neurons may be degenerated and their number diminished after or concomitantly with the depletion of anterior horn neurons.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050812
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  • 29
    Electronic Resource
    Electronic Resource
    Hereditary dentatorubral-pallidoluysian atrophy: detection of widespread ubiquitinated neuronal and glial intranuclear inclusions in the brain (1998)
    Springer
    Acta neuropathologica 96 (1998), S. 547-552 
    Details
    ISSN: 1432-0533
    Keywords: Key words Dentatorubral-pallidoluysian atrophy ; Nuclear inclusion ; Ubiquitin ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We examined the brains and spinal cords of seven patients with clinicopathologically and genetically confirmed hereditary dentatorubral-pallidoluysian atrophy (DRPLA) using an antibody against ubiquitin, and found small, round immunoreactive intranuclear inclusions in both neurons and glial cells in various brain regions. Ubiquitinated neuronal intranuclear inclusions (uNIIs) were consistently found in the striatum, the pontine nuclei, the inferior olivary complex, the cerebellar cortex and the dentate nucleus. Ubiquitinated glial intranuclear inclusions (uGIIs) were found less frequently than uNIIs. Most of the inclusion-bearing nuclei were of an astrocytic nature. Immunostaining with an antibody against DRPLA protein revealed similar immunoreactive neuronal and glial intranuclear inclusions, but in much smaller in numbers compared with uNIIs and uGIIs. Electron microscopy showed that such inclusions were composed of granular and filamentous structures. These findings strongly suggest that, in DRPLA, the occurrence of uNIIs and uGIIs is directly related to the causative gene abnormality (an expanded CAG repeat encoding polyglutamine), that neurons are affected much more widely than previously recognized and that glial cells are also involved in the disease process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050933
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  • 30
    Electronic Resource
    Electronic Resource
    Congenital myopathy with mosaic fibers and interlacing sarcomeres: a new structural myopathy (1998)
    Springer
    Acta neuropathologica 96 (1998), S. 643-650 
    Details
    ISSN: 1432-0533
    Keywords: Key words Congenital myopathy ; Muscle fibers ; Ultrastructure ; Myofibrillar disarray
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A 44-year-old man presenting with dyspnoic attacks was found to be affected with congenital myopathy, rigid spine, restrictive respiratory insufficiency and cardiomyopathy. Muscle biopsy showed type 1 fiber predominance (65.7%) and hypotrophy, and characteristic changes in 43.9% of the type 1 fibers, consisting in alternating pale and dark staining on alkaline ATPase reacted sections in a mosaic pattern. Ultrastructural examination demonstrated bands of myofibrils at right angles or skew to the remaining myofibrils transversing the fibers. Myofibrillar disarray was always associated with loss of the Z-discs and actin filaments, and often with aggregation of mitochondria. The muscle biopsy findings in this patient suggest a new entity of congenital myopathy with clinical features of rigid spine, cardiomyopathy and restrictive respiratory insufficiency, characterized by peculiar abnormalities of ATPase staining in a mosaic pattern and, ultrastructurally, by zones of disorientation of the sarcomeres.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050946
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  • 31
    Electronic Resource
    Electronic Resource
    Ultracytochemistry of 3β-hydroxysteroid dehydrogenase in Leydig cell precursors and vascular endothelial cells of the postnatal rat testis (1998)
    Springer
    Anatomy and embryology 198 (1998), S. 101-110 
    Details
    ISSN: 1432-0568
    Keywords: Key words Adult-type Leydig cells ; Endothelium ; 3β-HSD ; Ultrastructure ; Differentiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In the biosynthesis of steroid hormones 3β-hydroxysteroid dehydrogenase (3β-HSD) is a key enzyme. The present report describes the subcellular localization of the enzyme in the fetal-type Leydig cells, the fibroblast-like precursors of adult-type Leydig cells and in endothelial cells of interstitial capillaries. Histochemical methods for light microscopy and ultracytochemical methods for electron microscopy were used on rat testes of postnatal day 15. 3β-HSD reactivity was located at subcellular levels by means of the ferricyanide method. A specific, distinct localization of reaction product in the form of copper ferrocyanide precipitates was observed on the membranes of the smooth endoplasmic reticulum not only in the fetal-type Leydig cells and the fibroblast-like precursors of adult-type Leydig cells, but also focally in the endothelial cells of interstitial blood capillaries. Topographically, the 3β-HSD-positive precursors were most often found in the outer layer of the boundary tissue and surrounding interstitial blood vessels. The capillaries with 3β-HSD-positive endothelial cells were usually located in the vicinity of 3β-HSD-positive Leydig cells. For the first time, 3β-HSD has been located at the subcellular level in precursors of adult-type Leydig cells and focally in capillary endothelial cells associated with them. Due to the close association between 3β-HSD-positive vascular endothelial cells and Leydig cells a paracrine relationship between the two cell types may be involved in the acute regulation of steroidogenesis by blood-borne luteinizing hormone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004290050168
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  • 32
    Electronic Resource
    Electronic Resource
    Structural and functional changes in skeletal muscle in anorexia nervosa (1998)
    Springer
    Acta neuropathologica 95 (1998), S. 632 
    Details
    ISSN: 1432-0533
    Keywords: Key words Anorexia nervosa ; Myopathy ; Muscle biopsy ; Ultrastructure ; Protein-energy malnutrition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Protein-energy malnutrition in anorexia nervosa is an under-recognised cause of muscle dysfunction. To characterise the skeletal myopathy that occurs in patients with severe anorexia nervosa, muscle function and structure were comprehensively examined in eight young adult female patients with severe (40%) self-induced weight loss. All of the patients showed impaired muscle function on strength and exercise measurement. The maximum voluntary contraction force for the patient group was significantly less than predicted values. Electromyography revealed myopathy in five of the patients, four of whom also had electro-physiological evidence of neuropathy. However, muscle biopsy specimens consistently showed myopathic changes with severe type 2 fibre atrophy but with no evidence of neuropathic changes. Ultrastructurally, there was separation and segmental loss of myofibrils and most biopsy samples contained abundant glycogen granules; we have previously reported that one of the most consistent biochemical abnormalities in these patients is impaired ischaemic lactate responses to forearm exercise. The result of severe protein-energy malnutrition on the musculo-skeletal system is a metabolic myopathy. Although the patients admitted to a variety of abnormal dieting behaviours, such as over-exercising and self-induced vomiting, no association was found between any of these and quantitative histological changes in the muscle biopsy samples. It is recommended that myopathy in anorexia nervosa be treated by instituting an appropriate refeeding programme.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050850
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  • 33
    Electronic Resource
    Electronic Resource
    Further observations on the gap-junction-rich cells in the deep muscular plexus of the rat small intestine (1998)
    Springer
    Anatomy and embryology 197 (1998), S. 135-141 
    Details
    ISSN: 1432-0568
    Keywords: Key words Interstitial cells of Cajal ; Ultrastructure ; Gap junction ; Intestine ; Motility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Interstitial cells forming many large gap junctions in the region of the deep muscular plexus of the rat small intestine were studied by electron microscopy and by three-dimensional cell models reconstructed from serial ultrathin sections. Two different profiles of cells were observed. Cells of the first profile are characterized by an elongated cell shape and by less electron-dense cytoplasm, containing many mitochondria, well-developed Golgi apparatus and free ribosomes. They mainly connect with smooth muscle cells of the main circular layer. In a three-dimensional cell model, the total area of the gap junctions occupies 1.3% of the cell surface. Cells of the second profile are characterized by the frequent occurrence of slender cytoplasmic processes, higher electron-dense cytoplasm, containing mitochondria, Golgie apparatus and well-developed rough endoplasmic reticulum, and numerous caveolae on the cell membrane. In this cell model, gap junctions occupy 0.8% of the cell surface. The ratio of gap junctions with the same profile of cells to the total gap junction area is 37.7%, which is more than three times greater than the 9.9% in cells of the first profile. These cells were closely associated with nerve terminals. It is likely that these cells with different profiles constitute subtypes with each other and cooperate for regulation of intestinal motility via the transmission of nerve signals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004290050125
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  • 34
    Electronic Resource
    Electronic Resource
    Abundant minute myotubes in a patient who later developed centronuclear myopathy (1998)
    Springer
    Acta neuropathologica 95 (1998), S. 547-551 
    Details
    ISSN: 1432-0533
    Keywords: Key words Congenital myopathy ; morphometry ; Ultrastructure ; Fetal myogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Centronuclear myopathy (CNM) is a congenital myopathy which manifests itself as a severe neonatal (also termed myotubular myopathy), early-onset, or adult form. The histological pattern of each is marked by a considerable number of nuclei of muscle fibers being internally placed. Owing to their remote resemblance to myotubes, and their expression of developmentally regulated proteins, most authors now favor the concept that myogenesis is arrested or delayed in this disease. We here present two muscle biopsy specimens of a patient with early-onset CNM, taken at the age of 5 months and 14 years, respectively. The first biopsy sample contained internally placed nuclei in 7% of the muscle fibers, abundant minute myotubes, and hypertrophic muscle fibers. The second biopsy sample showed internally placed nuclei in 40% of the muscle fibers, and hypotrophic fibers. We suggest that the histological findings in early-onset CNM are the result of a complex dynamic process, which includes a delay in maturation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050836
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  • 35
    Electronic Resource
    Electronic Resource
    Ultrastructural and permeability features of microvessels in the olfactory bulbs of SAM mice (1998)
    Springer
    Acta neuropathologica 96 (1998), S. 261-270 
    Details
    ISSN: 1432-0533
    Keywords: Key words Aging ; Blood-brain barrier ; Horseradish peroxidase ; Senescence-accelerated mouse ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The ultrastructural features of microvessels showing increased permeability to intravenously injected horseradish peroxidase (HRP) were examined in the olfactory bulbs of senescence-accelerated prone mice (SAMP8), which showed age-related deficits in learning and memory, and senescence-accelerated resistant mice (SAMR1), which did not show the age-related deficits. HRP was visualized with tetramethyl benzidine (TMB) and diaminobenzidine (DAB) for light and electron microscopic examination, respectively. In the olfactory bulbs of 13-month-old SAMP8 mice, the staining reaction with TMB for HRP appeared in the neuropil of central area (granule cell layer and subependymal layer), in the pia mater and in the vascular wall. Some vessels located in the central area showed several changes observed at the ultrastructural level. The cytoplasm of the endothelial cells, especially in the arterioles, was segmentally thickened and contained numerous vesicles and vacuoles, some of which were HRP positive. The endothelial cell surface was occasionally undulated with microvillous protrusions. Membranous inclusions within the basal lamina, suggesting the cellular (presumably pericytal) degeneration, were frequently observed, especially in venules. The collagen deposits were occasionally observed in the subendothelial space of some vessels. Perivascular cells with vacuolated inclusions or lipid-like droplets were present around some vessels in the central area of the olfactory bulbs of aged SAMP8 mice. On the other hand, in the microvessels located in the areas negative for HRP-TMB reaction, except the vessel walls, the cytoplasm of the endothelial cells with smooth luminal surface was flattened and some vesicles located there contained HRP-DAB reaction product. Weak staining reaction with TMB for HRP appeared also in the central area of the olfactory bulbs of 3-month-old SAMP8 mice and 3- and 13-month-old SAMR1 mice. The cytoplasm of the endothelial cells in the olfactory bulbs of these mice was focally thickened and contained some cytoplasmic vesicles. Occasionally, the endothelial cell surface was moderately undulated with few microvillous protrusions. Membranous inclusions within the basal lamina were not observed in these animals. These findings indicate that the endothelial cells and pericytes in some vessels located in the central area of the olfactory bulb of aged SAMP8 mice, which show staining reaction with TMB for HRP, are ultrastructurally changed, suggesting their altered functions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004010050893
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  • 36
    Electronic Resource
    Electronic Resource
    Barrier recovery is impeded at neutral pH, independent of ionic effects: implications for extracellular lipid processing (1998)
    Springer
    Archives of dermatological research 290 (1998), S. 215-222 
    Details
    ISSN: 1432-069X
    Keywords: Key words Barrier function ; pH ; Stratum corneum ; Lamellar body ; Lipid content ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Epidermal permeability barrier homeostasis requires the postsecretory processing of polar lipid precursors into nonpolar lipid products within the stratum corneum (SC) interstices by a family of lipid hydrolases. A specific requirement for β-glucocerebrosidase (β-GlcCer’ase), which exhibits a distinct acidic pH optimum, is particularly well documented. Therefore, we sought to determine whether the recovery of the barrier after acute insults requires acidification of the SC. We examined permeability barrier recovery by assessing changes in transepidermal water loss (TEWL), SC membrane ultrastructure utilizing ruthenium tetroxide (RuO 4 ) postfixation, and β-GlcCer’ase activity by in situ zymography at an acidic vs neutral pH. Barrier recovery proceeded normally when acetone-treated skin was exposed to solutions buffered to an acidic pH. In contrast, the initiation of barrier recovery was slowed when treated skin was exposed to neutral or alkaline pH, regardless of buffer composition. In addition, enhancement of the alkaline buffer-induced delay in barrier recovery occurred with Ca 2+ and K + inclusion in the buffer. Moreover, the pH-dependent alteration in barrier recovery appeared to occur through a mechanism that was independent of Ca 2+ - or K + -controlled lamellar body secretion, since both the formation and secretion of lamellar bodies proceeded comparably at pH 5.5 and pH 7.4. In contrast, exposure to pH 7.4 (but not pH 5.5) resulted in both the persistence of immature, extracellular lamellar membrane structures, and a marked decrease in the in situ activity of β-GlcCer’ase. These results suggest first that an acidic extracellular pH is necessary for the initiation of barrier recovery, and second that the delay in barrier recovery is a consequence of inhibition of postsecretory lipid processing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004030050293
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  • 37
    Electronic Resource
    Electronic Resource
    Morphology of starch in surimi gels (1998)
    Springer
    Zeitschrift für Lebensmittel-Untersuchung und -Forschung 206 (1998), S. 38-43 
    Details
    ISSN: 1431-4630
    Keywords: Key words Starch ; Gels ; Kamaboko ; Surimi ; Gelatinization ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The purpose of this work was to study the changes undergone by starch during heat-induced surimi gel preparation either with or without added egg white, and their effects on the structure of gels using light and scanning electron microscopy. Gels were made from SA-grade Alaska pollack (Theragra chalcogramma) surimi with: (1) salt (3%, w/w); (2) salt and waxy corn starch (3% and 5%, respectively w/w); or (3) salt, waxy corn starch and egg white (3%, 5% and 5%, respectively, w/w). Final moisture was adjusted to 73% or 83%. The gels were prepared by prior setting (40°C, 30 min, followed by 90°C, 30 min) or cooking (90°C, 30 min). The prepared gel was frozen and stored at –20°C (±1°C) until analysis. Samples were observed by light and scanning electron microscopy. The results show that the starch granules alter according to the processing conditions, with the predominance of crystalline or amorphous morphology depending upon the availability of heat and water. Large cavities formed in the protein gel matrix during setting can trap water; as a result, water availability is limited for starch to swell and gelatinize even in the high-moisture gel.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002170050210
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  • 38
    Electronic Resource
    Electronic Resource
    Primäres Plattenepithelkarzinom der weiblichen Brustdrüse (1998)
    Springer
    Der Pathologe 19 (1998), S. 373-378 
    Details
    ISSN: 1432-1963
    Keywords: Schlüsselwörter Metaplastische Brustdrüsenkarzinome ; Plattenepithelmetaplasie ; Plattenepithelkarzinom ; Immunhistologie ; Elektronenmikroskopie ; Zytophotometrie ; Key words Pure squamous cell carcinoma ; Mammary gland ; Squamous metaplasia ; Immunohistology ; Cytophotometry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Squamous metaplasia can be demonstrated in about 4% of all invasive carcinomas of the breast. Primary squamous cell carcinomas of the breast are rare, since they occur in less than 1% of all primary invasive breast carcinomas. In order to classify a breast tumor as a primary squamous cell carcinoma one must exclude an epidermal origin, especially from the nipple region and the possibility of metastatic infiltration of the breast by a squamous cell carcnoma from a different location. Causative and formal pathogenesis of primary squamous cell carcinoma of the breast is not clear. A pluripotent embryonal stem cell origin is discussed, considering the phylogenetic descent of the mammary gland from skin appendages. Squamous metaplasia is also suggested to be a precursor of squamous cell carcinoma. Here endocrine stimulation and chronic inflammation may both play an inductive role. The number of published cases of squamous cell carcinomas developing years and decades after implantation of silicon prostheses has increased in recent years. These tumors probably develop on top of squamous metaplasia induced by the inflammatory pseudocapsule. Estimating the prognosis and therapeutic management in patients with squamous cell carcinoma of the breast should follow the same guidelines as for other squamous cell cancers.
    Notes: Zusammenfassung Plattenepithelmetaplasien werden bei etwa 4% aller invasiven Brustdrüsenkarzinome beschrieben. Reine Plattenepithelkarzinome der weiblichen Brustdrüse sind mit einem Anteil von wahrscheinlich unter 1% an allen invasiven epithelialen Tumoren der Mamma selten. Von einem primären Plattenepithelkarzinom der Brustdrüse darf nur gesprochen werden, wenn zum einen der Ursprung von der Epidermis, insbesondere auch im Bereich des Mamillentrichters ausgeschlossen ist und zum anderen keine metastatische Infiltration in die Brustdrüse durch ein Plattenepithelkarzinom anderer Organlokalisation vorliegt. Die kausale und formale Pathogenese der primären Plattenepithelkarzinome der Brustdrüse ist unklar. Zum einen wird ein Ursprung von pluripotenten embryonalen Stammzellen diskutiert, wobei bedacht wird, daß die Brustdrüse entwicklungsgeschichtlich ein Hautanhangsgebilde darstellt. Zum anderen werden Plattenepithelmetaplasien als Vorstufe der Plattenepithelkarzinome diskutiert, wobei neben einer endokrinen Induktion auch länger bestehende Entzündungsreize eine Rolle spielen sollen. In den letzten Jahren wird immer häufiger darüber berichtet, daß oft Jahrzehnte nach Implantation von Silikonprothesen periprothetische Plattenepithelkarzinome entstehen, die wahrscheinlich über die Stufe einer Plattenepithelmetaplasie der entzündlichen Prothesenpseudokapsel entstehen. Die Abschätzung der Prognose und therapeutische Maßnahmen bei primären Plattenepithelkarzinomen der Brustdrüse sollten an den Erfahrungen mit Plattenepithelkarzinomen anderer Organlokalisation ausgerichtet werden.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002920050300
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  • 39
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    Electronic Resource
    Ultrastructural and molecular study of plastid inheritance in Abies alba and some Abies hybrids (1998)
    Springer
    Sexual plant reproduction 11 (1998), S. 284-291 
    Details
    ISSN: 1432-2145
    Keywords: Key words Abies ; Egg cell ; Plastid inheritance ; RFLP ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  The ultrastructure of egg cells in Abies alba was examined to elucidate the lack of maternal inheritance of plastids. Before fertilization, maternal plastids are absent in the perinuclar zone containing mainly mitochondria and smooth endoplasmic reticulum. During egg cell development the maternal plastids are transformed into large inclusions which are situated mostly towards the periphery of the egg cell, and finally disintegrate. As a consequence, they do not participate in zygote formation. RFLP analysis of cpDNA of parental trees and their F1 interspecific hybrids (A. alba×A. numidica, A. alba×A. nordmanniana, A. nordmanniana×A. Alba) using HindIII and BamHI showed a paternal mode of cpDNA inheritance. Paternal inheritance has also been found with PCR/RFLP analysis of cpDNA from parental trees and their hybrids (A. alba×A. pinsapo, A. pinsapo×A. alba, A. pinsapo×A. numidica) using ApaI and HaeIII digests, as well as in the crosses of A. cephalonica×A. nordmanniana, A. nordmanniana×A. cephalonica, A. cephalonica×A. numidica using TagI digests.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004970050155
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  • 40
    Electronic Resource
    Electronic Resource
    Differences in the initiation of the zygotic and parthenogenetic pathway in the Salmon lines of wheat: ultrastructural studies (1998)
    Springer
    Sexual plant reproduction 11 (1998), S. 121-130 
    Details
    ISSN: 1432-2145
    Keywords: Key words Egg cell ; Parthenogenesis ; Synergid ; Ultrastructure ; Wheat ; Zygote
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  The ultrastructure of the egg apparatus of the sexual (aestivum)-Salmon line (aS) and the isogenic but alloplasmic (kotschyi)-Salmon line (kS) of the Salmon system of wheat was studied by transmission electron microscopy 3 days before and during anthesis. Additionally, the zygotic stage of aS, 17 h after pollination, was included. Metabolic activity of egg cells from the sexual line aS was low 3 days before anthesis and increased dramatically after pollination and fertilization. This timing of increased activity was evident because of changes occurring in the egg cell nucleus and nucleolus, polysomes, endoplasmic reticulum and Golgi apparatus, and the completion of the cell wall around the zygote. In contrast to the sexual line, the egg cell of the parthenogenetic line showed high activity 3 days before anthesis. The metabolic and ultrastructural characters observed in the nucleus and cytoplasm of the kS line 3 days before and during anthesis corresponded with those of the isogenic sexual line aS during anthesis and 17 h after pollination, respectively. High metabolic activity observed in the persistent synergid of kS may be connected with the occurrence of additional embryos in seeds (twins) of this line.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004970050129
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  • 41
    Electronic Resource
    Electronic Resource
    Phylogenetic affiliation and ultrastructure of uncultured magnetic bacteria with unusually large magnetosomes (1998)
    Springer
    Archives of microbiology 169 (1998), S. 136-147 
    Details
    ISSN: 1432-072X
    Keywords: Key words Magnetic bacteria ; Biomineralization ; Magnetite ; 16S rRNA ; In situ hybridization ; Ultrastructure ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Natural enrichments of magnetic bacteria from the Itaipu lagoon near Rio de Janeiro were dominated by coccoid-to-ovoid morphotypes that produced unusually large magnetosomes. To determine the phylogenetic position of these unusual microorganisms, 16S rRNA genes were retrieved from bacteria magnetically separated from sediment of the Itaipu lagoon by in vitro amplification and cloning of PCR products into a plasmid vector. Partial sequencing of the obtained clones revealed two clusters of closely related sequences affiliated to a distinct lineage consisting exclusively of magnetic bacteria within the α-subclass of Proteobacteria. For a detailed phylogenetic analysis, several almost complete sequences of the 16S rRNA genes were determined. One representative clone of each cluster provided a PCR template for the in vitro transcription of group-specific polynucleotide probes complementary to a variable region of the 16S rRNA molecule. At least three different morphotypes of magnetic bacteria were reliably identified by post-embedding hybridization of ultra-thin sections. Electron microscopic analyses of hybridized cells enabled for the first time a detailed description of the morphological variety and ultrastructure of phylogenetically identified, uncultured magnetic bacteria. Two distinct coccoid bacteria were identified by the transcript probe complementary to the 16S rRNA sequence mabrj12, whereas the probe complementary to the sequence mabrj58 allowed the identification of an ovoid morphotype that displayed magnetosomes with the largest volumes observed to date.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002030050553
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  • 42
    Electronic Resource
    Electronic Resource
    Visualization of interstitial cells of Cajal in the mouse colon by vital staining (1998)
    Springer
    Cell & tissue research 292 (1998), S. 275-282 
    Details
    ISSN: 1432-0878
    Keywords: Key words Interstitial cells (Cajal) ; Large intestine ; Fluorescent dyes ; Vital staining ; Ultrastructure ; Mouse (BALB/c)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Interstitial cells of Cajal (ICCs) are believed to be a major element in generating the spontaneous rhythm of the gastrointestinal tract. A prominent problem in the study of these cells has been the difficulty in observing them in intact tissues. We used the lipophilic dye DiI to stain ICCs in the submucosal-circular muscle border of freshly dissected mouse colon. The placement of small DiI crystals in this area resulted in the labeling of ICC-like cells. Two main morphological cell types, viz., bipolar and multipolar, were noted. Bipolar cells had two primary processes emerging from the poles of an elongated soma. The mean length of these processes was 78.7 μm. These cells constituted 42.3% of the sample (n=105). Multipolar cells (54.3% of total) had a less elongated soma and extended 3–6 main processes whose mean length was 56.3 μm. These processes showed no preferred direction. The length of the primary processes of bipolar cells was 40% greater than that of multipolar cells (P〈0.02). Three cells (2.9%) had only one primary process. The DiI stain could be converted into a stable electron-opaque product. Electron-microscopic observations showed that these cells had the typical appearance of ICCs reported in previous studies. This staining method should be useful for physiological investigations of ICCs in gastrointestinal tissues.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051058
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  • 43
    Electronic Resource
    Electronic Resource
    Cutaneous glands of male and female impalas (Aepyceros melampus): seasonal activity changes and secretory mechanisms (1998)
    Springer
    Cell & tissue research 292 (1998), S. 377-394 
    Details
    ISSN: 1432-0878
    Keywords: Key words Cutaneous scent glands ; Apocrine glands ; Myoepithelial cells ; Holocrine glands ; Ultrastructure ; Lectins ; Cytokeratins ; Impala ; Aepyceros melampus (Artiodactyla)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The cutaneous glands of the forehead and the metatarsus were studied by histological and histochemical methods and electron microscopy in adult male and female impalas in various seasons of the year. All glandular areas consist of apocrine and holocrine glands, which, however, occur in different proportions. Our findings in the apocrine gland cells suggest (1) the synthesis and exocytosis of a glycoproteinaceous secretory product stored in secretory granules, (2) typical apocrine secretion of the transformed apical cytoplasm, and (3) transepithelial fluid transport. The Golgi apparatus and apical membrane have binding sites for several lectins (PNA, HPA, RCA I, WGA). Cytokeratins 7, 14 and 19 are expressed at various intracellular localizations, suggesting an active role in the secretory mechanisms. The glands of the male forehead show marked seasonal changes in activity that are correlated with the main phases of the reproductive cycle, with the highest cellular activity occurring during the rut in April/May. The female forehead glands are only moderately developed and do not undergo seasonal changes. The metatarsal glands are of equal size in males and females and show no seasonal changes in activity. This study supports the hypothesis that (1) forehead glands in the male have a signaling role in the rut and (2) the metatarsal glands have a more general, probably social role maintaining and restoring contact between herd members.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051068
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  • 44
    Electronic Resource
    Electronic Resource
    Segmental muscle fiber lesions after repetitive eccentric contractions (1998)
    Springer
    Cell & tissue research 293 (1998), S. 165-171 
    Details
    ISSN: 1432-0878
    Keywords: Key words Muscle injury ; Cytoskeleton ; Sarcomere organisation ; Immunohistochemistry ; Ultrastructure ; Rabbit (New Zealand White)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Immunohistochemical and electron-microscopic techniques were used to analyze the extensor digitorum longus muscles of New Zealand White rabbits 1 h, 1 day, 3, 7, and 28 days after repetitive eccentric contractions. Loss of the cytoskeletal protein desmin was the earliest manifestation of injury. Apart from 1 h post-exercise, all desmin-negative fibers stained positively with antibody to plasma fibronectin, indicating loss of cellular integrity accompanying cytoskeletal disruption. Fiber sizes were significantly increased from 1–7 days after exercise. The large (hyaline) fibers found in histological sections after repetitive eccentric contractions resulted from segmental hypercontraction of the fiber. This phenomenon occurred proximally and distally to plasma membrane lesions of the muscle fiber and necrosis and manifested itself as very short sarcomere lengths. Thus, in serial sections, staining characteristics, sizes and shapes of one and the same fiber often varied dramatically. We conclude that the following sequence of events occurs: cytoskeletal disruptions, loss of myofibrillar registry, i.e., Z-disk streaming and A-band disorganization, and loss of cell integrity as manifested by intracellular plasma fibronectin stain, hypercontracted regions, and invasion of cells. When a fiber is disrupted, the remaining intact fibers apparently take up the tension put on the muscle and later fewer fibers are subjected to eccentric contractions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051108
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  • 45
    Electronic Resource
    Electronic Resource
    Electron-immunocytochemical localization of P2X1 receptors in the rat cerebellum (1998)
    Springer
    Cell & tissue research 294 (1998), S. 253-260 
    Details
    ISSN: 1432-0878
    Keywords: Key words P2X1 receptor ; Ultrastructure ; Cerebellum ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The distribution of the P2X1 subtype of purinoceptors associated with the extracellular activities of ATP was studied in the rat cerebellum at the electron-microscope level. Receptors were labelled with peroxidase-antiperoxidase and the avidin-biotin-peroxidase complex for immunocytochemistry. Immunoreactivity to P2X1 receptors was localized in subpopulations of synapses between varicosities of parallel fibres of granule cells and dendritic spines of Purkinje cells. Unlabelled varicosities of parallel fibres formed asymmetric synapses with labelled dendritic spines, whereas labelled varicosities of parallel fibres formed asymmetric synapses with unlabelled dendritic spines. P2X1 immunoreactivity was also localized in some astrocyte processes. The functional significance of these findings is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051175
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  • 46
    Electronic Resource
    Electronic Resource
    Remodeling of neural, glial, and tracheal cell populations in the developing Manduca wing (1998)
    Springer
    Cell & tissue research 294 (1998), S. 367-375 
    Details
    ISSN: 1432-0878
    Keywords: Key words Neurons ; Glia ; Tracheae ; Wing ; Ultrastructure ; Moth ; Manduca sp.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  This ultrastructural examination of sensory nerves of the Manduca wing has revealed that extensive remodeling occurs among insect sensory neurons and their associated glial cells between pupation and adult emergence. Systematic counts of axons in particular wing nerves throughout adult development have shown that a decrease in axon number per nerve occurs after day 6. The neurons and glial cells that die are believed to be cells present at pupation that have no apparent sensory function but that probably function as guidance scaffolding for neurons and glia that are born after pupation. Despite the loss of several axons from each wing nerve, these nerves continue to grow in diameter during the latter half of adult development as some of the surviving axons increase severalfold in diameter. Each growing wing nerve in turn apparently functions as a scaffold for the proximal to distal growth of adult tracheae. A correspondence exists between adult nerve pathways and adult tracheal pathways, with each trachea maintaining intimate contact with a wing nerve along its entire length.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051186
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  • 47
    Electronic Resource
    Electronic Resource
    Ultrastructure of the endolymphatic sac in the larva of the Japanese red-bellied newt Cynops pyrrhogaster (1998)
    Springer
    Cell & tissue research 291 (1998), S. 549-559 
    Details
    ISSN: 1432-0878
    Keywords: Key words Endolymphatic sac ; Ultrastructure ; Fluid transport ; Otoconia ; Newt ; Cynops pyrrhogaster (Urodela)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The ultrastructure of the endolymphatic sac (ES) of the late stage larva of the Japanese red-bellied newt, Cynops pyrrhogaster (stage 57), was examined by light and transmission electron microscopy. The two endolymphatic sacs are located at the dorsal-medial side of the otic vesicle on the dorsal-lateral side of the midbrain in the cranial cavity. The wall of the sac is composed of a layer of cubical epithelial cells with loose, interposed intercellular spaces. The sac contains a large luminal cavity, in which endolymph and numerous otoconia are present. The epithelial cells of different portions of the sac have a similar structure. These cells contain an abundance of cytoplasmic organelles, including ribosomes, Golgi complexes, and numerous vesicles. Two types of vesicles are found in the epithelial cells: the “floccular” vesicle and the “granular” vesicle. The floccular vesicles are located in the supra- and lateral-nuclear cytoplasm and contain flocccular material. The granular vesicles have a fine granular substance and are usually situated apposed to the apical cell membrane. The granular vesicles are suggested to be secreted into the lumen, while the floccular vesicles are thought to be absorbed from the lumen and conveyed to the intercellular spaces by the epithelial cells. The apical surfaces of the epithelial cells bear numerous microvilli. Apparently floating cells, which bear long microvilli on the free surfaces, are observed in the lumen of the ES. Based on the fine structure, the function of the endolymphatic sac of the newt Cynops pyrrhogaster is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051024
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  • 48
    Electronic Resource
    Electronic Resource
    Pleated septate junctions in leech photoreceptors: ultrastructure, arrangement of septa, gate and fence functions (1998)
    Springer
    Cell & tissue research 293 (1998), S. 253-269 
    Details
    ISSN: 1432-0878
    Keywords: Key words Septate junctions ; Ultrastructure ; Permeability ; Ions ; Epithelium ; Photoreceptor ; Hirudo medicinalis (Hirudinea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  The leech photoreceptor forms a unicellular epithelium: every cell surrounds an extracellular “vacuole” that is connected to the remaining extracellular space via narrow clefts containing pleated septate junctions. We analyzed the complete structural layout of all septa within the junctional complex in elastic brightfield stereo electron micrographs of semithin serial sections from photoreceptors infiltrated with colloidal lanthanum. The septa form tortuous interseptal corridors that are spatially continuous, and open ended basally and apically. Individual septa seem to be impermeable to lanthanum; interseptal corridors form the only diffusional pathway for this ion. The junctions form no diffusion barrier for the electron-dense tracer Ba2+, but they hinder the diffusion of various hydrophilic fluorescent dyes as demonstrated by confocal laser scanning microscopy (CLSM) of live cells. Even those dyes that penetrate gap junctions do not diffuse beyond the septate junctions. The aqueous diffusion pathway within the septal corridors is, therefore, less permeable than the gap-junctional pore. Our morphological results combined with published electrophysiological data suggest that the septa themselves are not completely tight for small physiologically relevant ions. We also examined, by CLSM, whether the septate junctions create a permeability barrier for the lateral diffusion of fluorescent lipophilic dyes incorporated into the peripheral membrane domain. AFC16, claimed to remain in the outer membrane leaflet, does not diffuse beyond the junctional region, whereas DiIC16, claimed to flip-flop, does. Thus, pleated septate junctions, like vertebrate tight junctions, contribute to the maintenance of cell polarity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051117
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  • 49
    Electronic Resource
    Electronic Resource
    Internal division of capillaries in rat skeletal muscle in response to chronic vasodilator treatment with α1-antagonist prazosin (1998)
    Springer
    Cell & tissue research 293 (1998), S. 293-303 
    Details
    ISSN: 1432-0878
    Keywords: Key words Angiogenesis ; Capillary growth ; Prazosin ; Shear stress ; Skeletal muscle ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Chronic vasodilatation represents a stimulus for capillary growth associated with increased luminal shear stress. We have examined the ultrastructure of more than 2000 capillaries to establish whether the sequence of angiogenesis in response to this stimulus is similar to that described during development and under pathological circumstances. Administration of the α1-blocker prazosin to rats for 2 weeks led to a greater capillary length density in extensor hallucis proprius muscles without any change in capillary tortuosity: J v(c,f)=262±54 compared with 350±17 mm–2, control compared with prazosin (P〈0.002). There were obvious signs of endothelial cell (EC) activation after prazosin treatment, including an increased proportion of capillaries with rough endoplasmic reticulum, large cytoplasmic vacuoles, thickened endothelium and an irregular luminal surface. Capillaries from control muscles had a maximum of three ECs in cross section, whereas four ECs were noted in 0.8+0.5% of capillaries after 1 week (n.s.) and 2.5±0.9% after 2 weeks (P〈0.01) of treatment. This could be due to elongation and/or migration of ECs, as cell proliferation has not been described at these time points. There was also an increase in the proportion of capillaries having a narrow, slit-like lumen (1.7±0.8% of controls; 7.1±1.9% at 1 week; 8.8±2.5% at 2 weeks; P〈0.02), some of which were smaller in size (less than 2 μm diameter) than in controls (3–5 μm) and/or “seamless”, i.e. lacking EC junctions. These may represent newly formed vessels. Focal discontinuity of the basement membrane and abluminal EC processes were rarely seen, and capillary growth by abluminal sprouting appeared to be very infrequent (less than 0.001% of profiles). Of more importance was growth starting from the luminal side. Significantly more thin cytoplasmic processes were observed protruding into the lumen of capillaries after 1 week (47.5±6.2%, P〈0.001) and 2 weeks of prazosin (34.2±5.5%, P〈0.05) than in control vessels (16.7±3.9%). Some of these traversed the entire lumen and connected with endothelium of the opposite side, probably involving membrane fusion, resulting in the appearance of a double lumen. Individual capillaries with a complete double lumen were observed after 2 weeks’ prazosin but comparatively rarely, in only four out of six muscles. These findings indicate a pattern of luminal growth which is completely different from intussusceptive growth previously described during development, and from the abluminal capillary sprouting seen under pathological circumstances.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051121
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  • 50
    Electronic Resource
    Electronic Resource
    Teliospores of smut fungi general aspects of teliospore walls and sporogenesis (1998)
    Springer
    Protoplasma 204 (1998), S. 155-169 
    Details
    ISSN: 1615-6102
    Keywords: Spores ; Ultrastructure ; Entorrhiza ; Microbotryum ; Tilletia ; Ustilago
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The concept and nomenclature for the elements of teliospore walls in smut fungi are presented and a survey of teliosporogenesis is given, as seen by light and transmission electron microscopy. Four developmental types are distinguished: the Ustilago, Microbotryum, Tilletia, and Entorrhiza type. In the Ustilago type, sporogenous hyphae are completely segmented into teliospore initials which are embedded in a hyaline matrix formed by gelatinised hyphal walls (found in species ofAnthracoidea, Cintractia, Heterotolyposporium, Kuntzeomyces, Macalpinomyces, Melanopsichium, Sporisorium, Testicularia, Tolyposporium junci, Trichocintractia, and species ofUstilago infecting members of the family Poaceae). In the Microbotryum type, septate sporogenous hyphae are also completely segmented into teliospore initials, however, they are not surrounded by a hyaline matrix (Microbotryum, Sphacelotheca, Ustilago spp. infecting dicotyledons). A yeast-like budding of teliosporogenic cells is observed for some species ofMicrobotryum, Sphacelotheca, andUstilago infecting dicotyledons. In the Tilletia type, teliospores differentiate locally in the sporogenous hyphae, in an apical or intercalary position, without a hyaline matrix (Conidiosporomyces, Doassinga, Entyloma, Erratomyces, Ingoldiomyces, Neovossia, Oberwinkleria, Rhamphospora, Tilletia). In all these types, the teliospore initials first develop a hyaline sheath under which the ornamentation, the exosporium, sometimes a middle layer, and the endosporium are successively deposited by the fungal cell. In the Entorrhiza type, the teliospores develop inside vital host cells with the wall of the sporogenous hypha included into the teliospore wall. The fungus develops a middle layer and an electron-transparent endosporium inside the hyphal wall while a layer forming the ornamentation is deposited onto the hyphal wall, probably by vesicles of dictyosomes of the host cell.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01280322
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    Megagametophytes of Douglas fir (Pseudotsuga menziesii) and hybrid larch (Larix × eurolepis) in culture: Multiplication of neck cells and the formation of binucleate cells (1998)
    Springer
    Protoplasma 204 (1998), S. 219-225 
    Details
    ISSN: 1615-6102
    Keywords: Neck cell proliferation ; Binucleate ; Douglas fir ; Conifers ; Genetic instability ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary To study the effect of culturing on megagametophytes of Douglas fir (Pseudotsuga menziesii) and hybrid larch (Larix × eurolepis), cones were collected at the time of fertilization and the megagametophytes were removed, then placed on medium. We used a modified Murashige and Skoog medium supplemented with 5% lactose and 10% polyethylene glycol 4000. A variety of cell types proliferated including prothallial, neck, and jacket cells. Some of these multiplying cells showed a binucleate condition. The prothallial cells of the apex divided and expanded. The neck cells formed clusters composed of more cells than normally found in situ; though otherwise they showed ultrastructural similarity to neck cells in situ. These neck cells had large numbers of active Golgi complexes, numerous large and small vacuoles, coated vesicles, smooth vesicles, a well-developed endoplasmic reticulum, and thickened cell walls. These are the first reports of neck cell multiplication and induction of a binucleate state for gymnosperm megagametophyte cells in vitro.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01280325
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    Callose deposition at plasmodesmata (1998)
    Springer
    Protoplasma 201 (1998), S. 30-37 
    Details
    ISSN: 1615-6102
    Keywords: Cell-to-cell communication ; Plasmodesmata ; Ultrastructure ; Wounding ; 2-Deoxy-D-glucose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The transport of ions and metabolites through plasmodesmata has been thought to be controlled at the neck region where the cytoplasmic annulus is constricted and where callose has also been localised. In order to determine the possible structural and functional effects of callose, its deposition was inhibited through incubation of the plant tissue with 2-deoxy-D-glucose (DDG) for 1 h prior to fixation in 2.5% glutaraldehyde. The inhibition of callose formation was monitored through aniline blue-induced fluorescence of callose. The neck region of the plasmodesmata fromAllium cepa L. roots treated with DDG exhibited a funnel-shaped configuration. This is in contrast to the plasmodesmata from tissue not incubated with DDG, which exhibited constricted necks similar to those previously reported. Both initial dissection and glutaraldehyde fixation induced neck constriction in plasmodesmata, however, dissection of tissue increased the frequency of constrictions. The inhibition of callose formation by chemical means showed that the neck constrictions and raised collars in this area are artefacts due to physical wounding and glutaraldehyde fixation. The external electron-dense material observed when tannic acid is included in the primary fixative appears to be unrelated to the deposition of callose at the neck region.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01280708
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    Physiological, structural, and immunological characterization of leaf and chloroplast development in cotton (1998)
    Springer
    Protoplasma 202 (1998), S. 23-37 
    Details
    ISSN: 1615-6102
    Keywords: Chloroplast development ; Cotton ; Fluorescence induction kinetics ; Ultrastructure ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Many of the studies of chloroplast ontogeny in higher plants have utilized suboptimal conditions of light and growth to assess development. In this study, we utilized structural, immunological, and physiological techniques to examine the development of the chloroplast in fieldgrown cotton (Gossypium hirsutum cv. “MD 51 ne”). Our youngest leaf sample developmentally was completely folded upon itself and about 0.5 cm in length; leaves of this same plastochron were followed for three weeks to the fully expanded leaf. The chloroplasts at the earliest stage monitored had almost all of the lamellae in small, relatively electron-opaque grana, with relatively few thylakoids which were not appressed on at least one surface. During the development of the thylakoids, the membranes increase in complexity, with considerable stroma lamellae development and an increase in the number of thylakoids per granum. Besides the increase in complexity, both the size and numbers of the chloroplast increase during the development of the leaf. Developmental changes in six thylakoid proteins, five stromal proteins, and one peroxisomal protein were monitored by quantitative immunocytochemistry. Even at the earliest stages of development, the plastids are equipped with the proteins required to carry out both light and dark reactions of photosynthesis. Several of the proteins follow three phases of accumulation: a relatively high density at early stages, a linear increase to keep step with chloroplast growth, and a final accumulation in the mature chloroplast. Photosystem-II(PS II)-related proteins are present at their highest densities early in development, with an accumulation of other parts of the photosynthetic apparatus at a latter stage. The early accumulation of PS-II-related proteins correlates with the much lower ratio of chlorophylla tob in the younger leaves and with the changes in fluorescence transients. These data indicate that some of the conclusions on chloroplast development based upon studies of intercalary meristems of monocots or the greening of etiolated plants may not be adequate to explain development of chloroplasts in leaves from apical meristems grown under natural conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01280872
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    Unusual pattern of mitosis in the free-living flagellateDimastigella mimosa (Kinetoplastida) (1998)
    Springer
    Protoplasma 201 (1998), S. 101-109 
    Details
    ISSN: 1615-6102
    Keywords: Kinetochore ; Kinetoplastida ; Intranuclear microtubules ; Mitosis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The three-dimensional ultrastructural organization of the mitotic apparatus ofDimastigella mimosa was studied by computer-aided, serial-section reconstruction. The nuclear envelope remains intact during nuclear division. During mitosis, chromosomes do not condense, whereas intranuclear microtubules are found in close association with six pairs of kinetochores. No discrete microtubule-organizing centers, except kinetochore pairs, could be found within the nucleus. The intranuclear microtubules form six separate bundles oriented at different angles to each other. Each bundle contains up to 8 tightly packed microtubules which push the daughter kinetochores apart. At late anaphase only, midzones of these bundles align along an extended interzonal spindle within the narrow isthmus between segregating progeny nuclei. The nuclear division inD. mimosa can be described as closed intranuclear mitosis with acentric and separate microtubular bundles and weakly condensed chromosomes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01280716
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    Cytomorphological characters supporting the taxonomic validity ofCyanothece (Cyanoprokaryota) (1998)
    Springer
    Plant systematics and evolution 210 (1998), S. 25-39 
    Details
    ISSN: 1615-6110
    Keywords: Cyanophyta ; Cyanobacteria ; Cyanothece ; Synechococcus ; Cyanobium ; Ultrastructure ; nucleoids ; taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The fine structure of the type species of the genusCyanothece Komárek 1976,C. aeruginosa, is described and compared with the main cytological characteristics of morphologically related members of the generaCyanobium, Cyanobacterium andSynechococcus. Several morphological features, such as cell walls with thick outer layers containing a special type of vesicles, position of thylakoids, “keritomy” (net-like appearance of protoplast caused by arrangement of thylakoids, net-like nucleoids and/or by tendency to form intrathylakoidal spaces) and a special structure of mucilaginous envelopes were found to be characteristic of this genus, supporting its separate position among coccal cyanoprokaryotes (cyanobacteria, cyanophytes). The taxonomic significance of ultrastructural features in all mentioned genera is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00984725
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    Teliospores of smut fungi teliospore connections, appendages, and germ pores studied by electron microscopy; phylogenetic discussion of characteristics of teliospores (1998)
    Springer
    Protoplasma 204 (1998), S. 202-218 
    Details
    ISSN: 1615-6102
    Keywords: Spore balls ; Germ areas ; Ultrastructure ; Phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Special features of teliospores in smut fungi are described, including teliospore connections, appendages, and germ pores. Balls of teliospores in species of many different genera cohere by remnants of hyphal walls, sheaths, and sometimes interlocking ornamentation. Teliospores are connected in pairs in species ofMycosyrinx andGeminago by special local structures. Appendages can be formed locally by persistent material from the sheath (Cintractia, Anthracoidea, Sphacelotheca), thickened parts of the spore wall (e.g.,Georgefischeria, Jamesdicksonia, Rhamphospora, Tolyposporella), or persistent walls of sporogenous hyphae (Rhamphospora, genera of the Tilletia relationship). Species ofGeorgefischeria, Jamesdicksonia, andTolyposporella have teliospore walls composed of more than three layers of different electron density. “Germ areas” corresponding to thinner parts of the spore wall are known, e.g., for species ofAnthracoidea, Cintractia, andUstilago infecting members of the family Poaceae, while distinct germ pores, one per teliospore, are found in some species ofThecaphora, “Tolyposporium”, andSporisorium. Teliospores ofMycosyrinx cissi have a germination ring. Characteristics of teliospores are used to discuss the phylogeny of smut fungi. A phylogenetic tree in accordance with teliospore characteristics is compared to those obtained from ultrastructural characteristics of host-parasite interaction, of septal pores, and from sequence data. Aspects of teliospore development help to define taxa at a high systematic level (Entorrhizales, Ustilaginales, Tilletiales/Entylomatales, Microbotryaceae), while details of ornamentation ontogeny delimit groups of genera (e.g., genera related toUstilago on members of the Poaceae andSporisorium, Cintractia andAnthracoidea, Tilletia) or single genera (e.g.,Melanopsichium, Dermatosorus, Mycosyrinx, Doassinga, Rhamphospora). Types of ornamentation (warty, reticulate), middle layers, teliospore balls, and germ pores evolved repeatedly by convergence. The smut teliospore itself probably evolved independently at least twice, or perhaps three (or more) times, in the Microbotryales, in the Entorrhizales, and in a common ancestor of the remainder of the Ustilaginomycetes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01280324
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    Teliospores of smut fungi teliospore walls and the development of ornamentation studied by electron microscopy (1998)
    Springer
    Protoplasma 204 (1998), S. 170-201 
    Details
    ISSN: 1615-6102
    Keywords: Spores ; Ultrastructure ; Microbotryum ; Tilletia ; Tolyposporium ; Ustilago
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The walls of mature teliospores and the development of ornamentation, as seen by transmission electron microscopy, are described for 37 genera of smut fungi, based on observations of ca. 120 species and on literature. Structural diversity of mature teliospore walls is due to differences in spore wall layers forming the spore wall (endosporium, middle layer, exosporium, ornamentation) and to different elements forming the ornamentation (exosporium, ornaments, sheath, hyphal wall, adjacent fungal cells, material of the host). During teliosporogenesis the outer layers are usually deposited first. At the beginning of the formation of the ornamentation the plasma membrane may be smooth or undulated carrying the developing ornaments on its tips or in its depressions. The ornamentation of some genera appears similar when seen by scanning electron microscopy, but can be the product of different developmental patterns (e.g., warts of species ofFarysia, Tilletia, andUstilago), however, warty and reticulate ornamentation can both be produced by similar developmental processes (shown, e.g., for species ofCintractia andTilletia). Typical structures of the mature teliospore wall and developmental patterns based on homologous similarities are described for the following groups of genera or species:Macalpinomyces, Melanopsichium, Sporisorium, andUstilago infecting members of the family Poaceae;Kuntzeomyces, Testicularia, andTrichocintractia; Anthracoidea, Cintractia, Heterotolyposporium piluliforme, andTolyposporium junci; Glomosporium, Sorosporium, andThecaphora; Conidiosporomyces, Erratomyces, Ingoldiomyces, Neovossia, Oberwinkleria, andTilletia; Entyloma, and genera of the Doassansia group;Liroa, Microbotryum, Sphacelotheca, Ustilago infecting dicotyledons, andZundeliomyces; Aurantiosporium, Fulvisporium, andUstilentyloma. Special characteristics of the teliospore wall were observed for the generaDermatosorus, Doassinga, Entorrhha, Farysia, Mycosyrinx, Rhamphospora, and some species ofTolyposporium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01280323
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    Solitary fibrous tumor of the pleura: report of a case with immunohistochemical and ultrastructural study (1998)
    Springer
    Medical molecular morphology 31 (1998), S. 147-150 
    Details
    ISSN: 1860-1499
    Keywords: Solitary fibrous tumor of the pleura ; Mesenchymal cell ; Immunohistochemistry ; CD 34 ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A solitary fibrous tumor of the pleura (SFTP) in a 37-year-old woman was reported as a rare pleural tumor based on morphological, immunohistochemical, and electron microscopic studies. The results showed that the tumor was composed of spindle-shaped cells forming fascicular and interlacing patterns with a mixture of mature collagen. The tumor cells coexpressed vimentin and CD34 and lacked cytokeratin reactivity. Ultrastructurally, there were abundant collagenous fibrillae surrounding spindle-shaped cells in which the junctional complex, basement membrane-like structure, and microvilli were not seen. From literature review and observation of the morphological features around the tumor, we consider that the tumor originated from the stromal cells subjacent to the mesothelium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01553783
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    Two cases of serous surface carcinoma of the peritoneum (1998)
    Springer
    Medical molecular morphology 31 (1998), S. 151-155 
    Details
    ISSN: 1860-1499
    Keywords: Serous adenocarcinoma ; Peritoneal neoplasm ; Immunohistochemistry ; Ultrastructure ; Case report
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two cases of serous surface carcinoma of the peritoneum (SSCP) are discussed. The first patient was a 48-year-old Japanese woman with abdominal pain and fullness. The second patient was a 66-year-old Japanese woman with abdominal fullness. In both patients, laparotomy revealed many tumor nodules on the peritoneal surface. However, the ovaries, the uterus, and other intraperitoneal organs were free from tumors. The serum levels of CA125 were excessively elevated. The tumor cells were arranged in a papillotubular pattern. Mitoses were frequent. Diastaseresistant PAS-positive, and hyaluronidase-resistant alcian blue-positive materials were observed. In immunohistochemistry, the tumor cells showed positive reactions for cytokeratin, EMA, CA125, and HBME-1, and, in contrast, negative reactions for CEA, thrombomodulin, vimentin, and HHF35. In analysis for Ber-EP4, all tumor cells of case 1 were negative, and a few tumor cells of case 2 were positive. Ultrastructurally, hobnail-shaped tumor cells rested on a continuous basal lamina. Each cell was attached to short desmosomes. Microvilli were slender, straight, and short, and some had core rootlets. Many primary lysosomes were aggregated in the basal portion of the cytoplasm. A few well-differentiated ciliated cells were present. These two cases were diagnosed as SSCP.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01553784
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    Repair of the surface epithelium after saponin-induced colonic mucosal injury in the rat (1998)
    Springer
    Medical molecular morphology 31 (1998), S. 1-9 
    Details
    ISSN: 1860-1499
    Keywords: Restitution ; Ultrastructure ; Cell migration ; Colon ; Saponin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The superficial colonic epithelia of rats were exposed to 1.0% saponin solution for 3 min and fixed at various periods thereafter. The repair or restitution process was observed by light as well as by transmission and scanning electron microscopy. The exposure of the luminal surface to saponin resulted in uniform and extensive damage to the superficial epithelial cells without affecting the cells in the crypts. At 3 min after saponin treatment, the damaged epithelial cells exfoliated from the mucosa and the basal lamina was exposed. Within 15 min, most of the exposed basal lamina was covered by squamous to low-cuboidal epithelial cells, probably migrating from the crypts. These epithelial cells extended large lamellipodia over the denuded basal lamina. After 15 min the damaged surface was completely covered with epithelial cells, which became columnar at 1 h. Tight junction protein ZO-1 became positive along the restituted epithelium. Proliferating-cell nuclear antigen (PCNA) staining showed that proliferation of epithelial cells occurred after the restitution. These results suggest that saponin treatment serves as a good model system to study colonic restitution, which is carried out by rapid migration from the remaining crypt cells, followed by cellular proliferation. Rapid formation of tight junctions spanning the damaged regions allows rapid restoration of the barrier function of the colonic epithelium.
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    URL: http://dx.doi.org/10.1007/BF01547942
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    Ultrastructural study of the mechanism of perineural extension in pancreatic cancer (1998)
    Springer
    Medical molecular morphology 31 (1998), S. 31-37 
    Details
    ISSN: 1860-1499
    Keywords: Pancreas ; Peripheral nerve ; Cancer ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Nerve invasion is one of the biological features of pancreatic cancer, and its mechanism remains to be determined. In this paper, we report on 37 pancreatic cancer specimens observed by immunohistochemical and electron microscopical techniques. The results showed that pancreatic cancer directly invaded and destroyed the perineurium. At the early stage of disease, the peripheral nerve and synaptic membrane were easily destroyed by cancer cells, and invasion and metastasis continuously advanced along the perineural space and central side of nerves. These results suggest that the soft tissue and nerve plexus on the dorsal region of the pancreas may contribute to the recurrence of pancreatic cancer after duodenopancreatectomy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01547946
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    Ultrastructural study of capillary angiogenesis in rat fetal hearts: Role of fibroblasts and myocardial clefts (1998)
    Springer
    Medical molecular morphology 31 (1998), S. 185-192 
    Details
    ISSN: 1860-1499
    Keywords: Rat fetal heart ; Capillary angiogenesis M ; Myocardial cleft ; Fibroblast ; Desmosome-like structure ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To determine the course of capillary angiogenesis in the rat fetal heart, transmission electron microscopy was used to examine the development of both capillaries and cardiomyocytes. In the 15-day-old embryo, the coronary vessels had spread into the superficial space. In the 16-day-old embryo, the coronary vessels began to enter the myocardium. In the 17-day-old embryo, the terminal vascular bed had developed and a marked increase in the population of myocytes was evident. In capillaries entering the myocardium, the outgrowth of endothelial cells into the myocardial cleft was evident. These clefts were formed by intercalated disk and desmosome-like structures. The fibroblasts were always found close to the capillaries or in contact with endothelial cells during the fetal stage to the first neonatal week. In the interstition period, the fibroblasts were not found close to the capillaries. These results are discussed in relation to the role of myocardial clefts and the role of fibroblasts in fetal capillary angiogenesis.
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    URL: http://dx.doi.org/10.1007/BF01545700
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    Malignant myoepithelioma of the oral palate: Ultrastructural and immunohistochemical studies and survey of the literature (1998)
    Springer
    Medical molecular morphology 31 (1998), S. 200-206 
    Details
    ISSN: 1860-1499
    Keywords: Malignant myoepithelioma ; Oral palate ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Malignant myoepithelioma arising in the palatal gland is extremely rare. The present study demonstrated ultrastructural and immunohistochemical features of malignant myoepithelioma transformed from long-standing benign myoepithelioma occurring in the palatal gland. Microscopically, the tumor mass was composed of plasmacytoid cells and epitheloid cells. The malignant feature was seen only at the area adjacent to the bone. Immunohistochemically, most of the cells were S-100 positive, whereas vimentin and keratin were only partially positive. Glial fibrillary acid protein (GFAP) was positive at the peripheral cells of the solid nests and epitheloid cells with myxoid stroma. Ultrastructurally, filament-rich cells, tonofilament-rich cells, and filament-poor cells were observed. At the area adjacent to the bone, the cells implying malignancy were filament-poor cells in which the luminal structures could be detected. From these findings, a scarcity of filaments in myoepitheliomatous components may imply a malignancy.
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    URL: http://dx.doi.org/10.1007/BF01545702
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    Ultrastructural changes in the smooth musculature of antrum and pylorus in presence of ulcus ventriculi (1974)
    Springer
    Research in experimental medicine 164 (1974), S. 1-17 
    Details
    ISSN: 1433-8580
    Keywords: Pathology ; Ultrastructure ; Smooth muscle ; Ulcus ventriculi ; Pathologie ; Ultrastruktur ; Glatte Muskulatur ; Ulcus ventriculi
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wurde die glatte Muskulatur des Antrum ventriculi sowie des Pylorus von 7 Patienten mit einem oder mehreren Ulcera ventriculi untersucht. Vergleichsweise konnten die entsprechenden Regionen des Magens von 5 normalen Organspendern der elektronenmikroskopischen Präparation zugeführt werden. Elektronenoptisch faßbare Veränderungen fanden sich noch 180 mm von der Ulcusläsion entfernt an den glatten Muskelzellen der inneren Rings- und der äußeren Längsmuskulatur sowie an den Gefäßen. Eine regelmäßig anzutreffende Veränderung der glatten Muskelzellen des Antrum und des Pylorus besteht in einer Strukturverdichtung des Kerns, der sarkoplasmatischen Grundsubstanz und der Myofilamente, kombiniert mit einer Vermehrung und Vergrößerung der hypolemmalen Vesikel, wie der dense bodies. Die Befunde werden als Ausdruck einer starken isometrischen Kontraktion der glatten Muskulatur im Antrum und im Pylorus bei Ulcera ventriculi gedeutet. Die geschilderten Befunde ließen sich an normalem Untersuchungsmaterial nicht erheben. Neben für das Magenulcus unspezifischen pathologischen Befunden an den glatten Muskelzellen, wie Anhäufung von Lipofuscin im Endoplasmahof und Lyse der Myofilamente, konnten spezifische Veränderungen gefunden werden. Diese betreffen die nur im Endoplasmahof differenzierten Räume des endoplasmatischen Reticulums. Bei zahlreichen Muskelzellen der Rings- und Längsmuskelschicht kommt eine extrem starke Quellung des endoplasmatischen Reticulums zur Beobachtung. Die Vacuolisation der endoplasmatischen Räume führt zu einer Verdrängung der übrigen Zellorganellen sowie der Myofilamente. Die Capillarendothelzellen weisen degenerative Veränderungen auf, die zu einem Sistieren cytopemptischer Vorgänge führen. In der arteriolären Gefäßstrecke findet sich vielfach eine starke Kontraktion der glatten Muskulatur bis zum völligen Verschluß der Gefäßlichtung. Auch diese Befunde ließen sich nur an den Mägen mit Ulcera ventriculi, nicht dagegen an dem normalen Vergleichsmaterial erheben.
    Notes: Summary The smooth musculature of antrum and pylorus of 7 patients with one or more stomach ulcers was examined by transmission electron microscopy. Corresponding regions of the stomachs of 5 normal organ donors served as control material. Electronmicroscopically visualizable changes were found at distances of up to 180 mm from the site of ulcerous lesion on the smooth muscle cells of the inner circular and outer longitudinal musculature, also on the blood vessels. A regularly occurring modification of the smooth muscle cells of antrum and pylorus consists of a structural condensation of the nucleus, of the sarcoplasmic ground substance and of the myofilaments, combined with augmentation and distension of the hypolemmal vesicles and of the dense bodies. These findings are interpreted as expression of a pronounced isometric contraction of the smooth musculature in the antrum and pylorus in presence of ulcera ventriculi. Such findings are not obtainable on normal material. Besides pathological modifications at the smooth muscle cells which are unspecific for stomach ulcer, such as accumulation of lipofuscin in the endoplasmatic lacunae and lysis of the myofilaments, specific changes were observed. These concern the interstices of the endoplasmic reticulum to be found only in the endoplasmatic lacunae. In numerous muscle cells of the circular and longitudinal muscle layers an extremely marked distension of the endoplasmic reticulum is found. Vacuolization of the endoplasmic cisternae causes displacement of the other cell organelles and of the myofilaments. The capillary endothelial cells show degenerative changes which bring about arrest of cytopemptic processes. In the arteriolar regions a strong contraction of the smooth musculature, at times resulting in complete occlusion of the vasal lumen, is frequently found. These findings, too, are obtainable only on stomachs with ulcera ventriculi and not on normal control material.
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    URL: http://dx.doi.org/10.1007/BF01851960
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    Ultrastruktur des proximalen Nierentubulus nach Behandlung mit einem Pentosanschwefelsäureester (1974)
    Springer
    Research in experimental medicine 164 (1974), S. 19-33 
    Details
    ISSN: 1433-8580
    Keywords: Kidney ; Rat ; Ultrastructure ; Proximal tubule degeneration ; Heparinoid ; Niere ; Ratte ; Ultrastruktur ; Proximale Tubulusdegeneration ; Heparinoid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 24 Std nach i.v. Injektion von 100 mg/kg eines Pentosanschwefelsäureesters (SP 54) sind in der Nierenrinde von Ratten schwere degenerative Veränderungen der proximalen Tubuluszellen zu beobachten. Das Tubulusepithel ist flachkubisch umgewandelt, das Tubuluslumen ist angefüllt mit ausgestoßenen Mitochondrien und anderen Zelltrümmern. Am stärksten betroffen ist die Pars contorta des proximalen Tubulus. Weniger stark veränderte Tubuluszellen sind angefüllt mit Cytosomen, die eine spezifische Feinstruktur haben oder gehäuft gegenüber Kontrollen Cytoplasmaprotrusionen in das Tubuluslumen aufweisen. Die akute Tubulusdegeneration ist ein spezifischer Effekt von SP 54. Heparin bewirkt nur eine leichte Schwellung des Tubulusepithels, die häufiger auftritt als bei Kontrolltieren.
    Notes: Summary 24 hrs after the intravenous injection of 100 mg/kg of a Pentosansulfuricacidester (SP 54) severe degenerative alterations are observed in the proximal tubular cells in rat kidney cortex. The tubular epithelium has changed to a single layer of elongated cubic cells. The tubular lumen is filled with cellular debris and extruded mitochondria. The greatest change is seen in the pars contorta of the proximal tubule. Less degenerated tubular cells have a great number of cytosomes with a specific substructure or have cytoplasmatic protrusions into the tubular lumen. This acute tubular degeneration is a specific event after the administration of SP 54 and is not seen after an equimolar dosis of Heparin. Heparin induces only a slight swelling of the tubular epithelium, more frequent seen as in the control animals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01851961
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    Ultrastructural studies on the intercellular bridges between the oocyte and follicle cells in the lizard Acanthodactylus scutellatus hardyi (1974)
    Springer
    Anatomy and embryology 143 (1974), S. 239-254 
    Details
    ISSN: 1432-0568
    Keywords: Oocyte ; Follicle cells ; Intercellular bridges ; Lizard ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Intercellular bridges connect the oocyte with its surrounding follicle cells. 2. Fibrillar bundles and microtubules are oriented along the length of the bridge. Mitochrondria, endoplasmic reticulum, multivesicular vesicles and other cytoplasmic components are also present in this region. 3. This communication may be very important for the flow of nutrients necessary for the growth of the oocyte.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00519868
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  • 67
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    Electron microscopic studies of the innervation of the rat kidney (1974)
    Springer
    Anatomy and embryology 145 (1974), S. 169-186 
    Details
    ISSN: 1432-0568
    Keywords: Renal innervation ; Rat ; Peripheral nerves ; Neuroeffector zones ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In der Rattenniere werden die muskelzellhaltigen arteriellen Gefäße und der juxtaglomeruläre Apparat innerviert. Blutgefäße mit Pericyten, porenhaltige Capillaren sowie die Tubuli der Rinde und des Markes werden nicht von Nervenfasern begleitet. Ganglienzellen wurden in der Rattenniere nicht beobachtet. Periphere Nerven mit einem ein-bis zweischichtigen Perineurium kommen im paravasalen Gewebe der Interlobar- und Arcuata-Arterien vor; sie enthalten neben zahlreichen marklosen Nervenfasern gewöhnlich auch 2–4 markhaltige. Nervenfaser-Bündel ohne perineurale Scheide finden sich im paravasalen Gewebe der Arcuata- und Interlobular-Arterien. Darüber hinaus sind in unmittelbarer Nachbarschaft der großen Arterien (Interlobar-, Arcuata- und Inter-lobular-arterien) und der Vasa afferentia marklose Nervenfasern und freie Axone vorhanden, die auch die proximalen Abschnitte der Vasa efferentia der subcapsulären und intermediären Rindenschicht begleiten. Im Nierenmark werden die juxtamedullären Vasa efferentia und die Arteriolae rectae innerviert; marklose Nervenfasern und freie Axone sind nur bis zur Außen-Innenstreifen-Grenze nachweisbar. Die Innervation der muskelzellhaltigen arteriellen Gefäße erfolgt durch aufgetriebene Axonabschnitte (Neuroeffektor-Zonen), die vorwiegend agranuläre Vesikel enthalten. Diese Strukturen liegen stets an der Grenze von Adventitia und Media bzw. Elastica externa; zwischen den glatten Muskelzellender Media wurden keine vesikelhaltigen Axonabschnitte gefunden. Als minimaler Abstand zwischen den vesikelhaltigen Axonabschnitten und den von einer Basalmembran umschlossenen glatten Muskelzellen (neuromuskuläre Distanz) wurden 600 Å gemessen. Die vorliegenden Ergebnisse werden mit den fluoreszenzmikroskopischen und histochemischen Untersuchungen über die adrenerge und cholinerge Innervation der Niere verglichen. Die sich aus diesem Vergleich ergebenden Probleme und funktionellen Konsequenzen für die Innervation der Niere sowie die Natur der cholinergen Fasern (afferente oder postganglionäre parasympathische Fasern) werden diskutiert.
    Notes: Summary The innervation of the rat kidney is defined by a system which supplies those arterial blood vessels whose walls contain smooth muscle cells and the juxtaglomerular apparatus. Vessels containing pericytes, or those vessels composed of an endothelium only, as well as the tubules of both the cortex and medulla, are not innervated. Furthermore, ganglion cells do not occur in the rat kidney. The nervous apparatus of the rat kidney consists of peripheral vegetative nerves, ensheathed by a perineurium, with 2–4 myelinated fibers running in the paravasal tissue of the interlobar and arcuate arteries, and of nerve bundles without a perineurial sheath in the paravasal tissue of the arcuate and interlobular arteries. Non-myelinated fibers and free axons occur in the immediate vicinity of the great arteries (interlobar, arcuate, and interlobular) and the vasa afferentia. Nerve fibers and free axons are also seen in the vicinity of only the proximal parts of those vasa efferentia which supply the cortical capillary plexus. The arteriolae rectae of the medulla, and their vasa efferentia, from which they arise, are innervated by non-myelinated fibers and free axons which accompany these arterial vessels only to the boundary of the outer and inner stripe of the outer zone of the medulla. The functional innervation of those vessels with smooth muscle cells results from neuro-effector zones which predominantly show agranular vesicles. These structures were never seen between the smooth muscle cells within the media; the minimum neuromuscular distance was 600 Å. The present findings are correlated with the lightmicroscopically demonstrated adrenergic and cholinergic innervation. The resultant problems and functional consequences of the innervation of the kidney, especially the nature of the cholinergic fibers (afferent or post-ganglionic parasympathetic fibers) are briefly discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00519727
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    Evolution ultrastructurale du labyrinthe de placenta de chatte (1974)
    Springer
    Anatomy and embryology 146 (1974), S. 1-20 
    Details
    ISSN: 1432-0568
    Keywords: Placenta ; Cat ; Differentiation ; Function ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé L'ultrastructure du labyrinthe de placenta de chatte a été étudiée du 45e au 63e jour de gestation. Cette formation endothéliochoriale est composée: d'un endothélium maternel hypertrophié et de cellules géantes déciduales; d'une couche de «substance inerte interstitielle»; du trophoblaste constitué d'une assise syncytiale continue (syncytiotrophoblaste) et d'une assise cellulaire discontinue (cytotrophoblaste); d'un endothélium foetal accompagné de son environnement mésenchymateux. Les capillaires foetaux envahissent progressivement le syncytiotrophoblaste. L'hypertrophie de l'endothélium maternel diminue en fin de gestation; de ce fait la distance, séparant le sang maternel du sang foetal, peut atteindre en certains points 2 μ. L'endothélium maternel, le syncytiotrophoblaste et l'endothélium foetal présentent des signes ultrastructuraux d'un rôle de transfert. La «substance inerte inerte interstitielle», qui sépare les tissus d'origine maternelle des tissus d'origine foetale, est constante mais d'épaisseur variable; elle est spécifique des structures endothéliochoriales. Les cellules géantes déciduales, dont le nombre diminue en fin de gestation comportent parfois un ou plusieurs «corps glycogéniques». Le syncytiotrophoblaste, siége d'activité de biosynthése de stéroïdes, est riche en ergastoplasme, ce qui autorise à postuler la synthése d'hormones protéiques.
    Notes: Summary The ultrastructure of feline placental labyrinth has been studied from the 45th to the 63rd day of gestation. The endotheliochorial structure is composed of: a thick hypertrophied maternal endothelium with giant decidual cells; an “interstitial inert substance”; a continuous syncytial layer (syncytiotrophoblast) and a discontinuous cellular layer (cytotrophoblast) of trophoblast; and a thin foetal endothelium with its surrounding mesenchyme. Foetal capillaries increasingly invade the syncytiotrophoblast. Maternal endothelial hypertrophy is reduced in the last days of gestation. Thus the interval between maternal and foetal bloods may in some areas become 2 μ, in late pregnancy. Foetal endothelium, syncytiotrophoblast, and maternal endothelium demonstrate ultrastructural features of transfer function. The “interstitial inert substance”, which separates maternal from foetal tissue was always evident though with variable thickness. The giant decidual cells which are reduced in late pregnancy, show one or several “glycogen bodies”. The syncytiotrophoblast, where some steroïd biosynthesis has been demonstrated, has an extensive rough endoplasmic reticulum suggestive of protein hormone synthesis activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00341379
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    Electronic Resource
    Differentiation of mouse leydig cell in anterior chamber of the rat eye (1974)
    Springer
    Anatomy and embryology 146 (1974), S. 219-224 
    Details
    ISSN: 1432-0568
    Keywords: Leydig cells ; Differentiation ; Explants ; Ultrastructure ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Testes of newborn mice not older than one day were transplanted into the anterior chamber of one eye of an adult male white Holtzman rat. The events observed in the Leydig cells of the grafted testes can be divided into two periods. Period one is marked by differentiation; period two, by dedifferentiation. In period one, the lipid and glycogen inclusions disappear, possibly owing to the gonadotropins of the host. In period two, which starts after day 15 post-grafting, the lipids and glycogen reappear; the Leydig cells now contain residual bodies, whereas the S.E.R. disappears. Immunological mechanisms can be implicated; it is suggested that the Leydig cells dedifferentiate because the host's gonadotropins may be incapable of evoking and/or activating the genetic memory of the grafted Leydig cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00315597
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    Ultrastructure of cleavage stages and preimplantation embryos of the baboon (1974)
    Springer
    Anatomy and embryology 147 (1974), S. 45-62 
    Details
    ISSN: 1432-0568
    Keywords: Baboon ; Cleavage stages ; Embryos ; Preimplantation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé La structure et l'ultrastructure des embryons de babouin sont étudiées dans la période précédant l'implantation. Six stades du développement embryonnaire sont observés 2, 3, 4, 5, 7 et 8 jours après la date présumée de fécondation. Dans les 3 premiers cas, on compte respectivement 2, 8 et 24 blastoméres. A 5 jours, il y a 30 à 40 cellules et un nombre dépassant 60, ultérieurement. Des cellules trophoblastiques primitives se différencient à 7 jours et une cavité de segmentation en forme de croissant apparaît au 8 ème jour. La zone pellucide est toujours présente à 8 jours, la période de préimplantation semblant plus longue chez le babouin que chez l'homme. Des particules de type C sont décrites dans la zone pellucide et les espaces périvitellin et interblastomériques. La transformation des mitochondries, des changements dans la répartition des ribosomes, des corps multivésiculaires, pseudocristallins et figures myéliniques, des nucléoles et amas granuleux intra-nucléaires s'observent chez le babouin comme chez certains autres Mammifères; par contre, les faisceaux fibrillaires cytoplasmiques sont absents. L'étude des changements de l'ultrastructure provoqués par des hormones et drogues permettrait de mieux évaluer la nocivité de ces substances pendant les premiers stades du développement embryonnaire des Primates.
    Notes: Summary The baboon preimplantation stages were examined using light and electron microscopy. Six cases were studied at 2, 3, 4, 5, 7 and 8 days estimated fertilization age. The first 3 specimens were composed of 2, 8 and 24 blastomeres respectively. At 5 days, 30 to 40 cells were counted and more than 60 cells in later stages. Primitive “trophoblast cells” differentiate at 7 days and a crescentic blastocoele appears at 8 days. Shedding of the zona pellucida is not observed in the 7 and 8 day specimens. The preimplantation period is longer in the baboon than in man. C-type viruses are observed in the zona pellucida, in the perivitelline and interblastomeric spaces. Microvilli and caveolae cover the periphery of the baboon conceptus. As in many other mammals, transformation of the mitochondria, changes in the ribosomes distribution, multivesicular bodies, myelin figures, nucleoli and intranuclear clusters of granules are described in the baboon. Cytoplasmic fibrous strands are not present as in the mouse. Experiments on the influence of hormones and drugs on ultrastructural changes would help to evaluate the importance of biohazards during the early development of primates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317963
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    The ultrastructure of the thin loop limbs of the mouse kidney (1974)
    Springer
    Anatomy and embryology 147 (1974), S. 1-18 
    Details
    ISSN: 1432-0568
    Keywords: Mouse kidney ; Thin limbs ; Ultrastructure ; Renal concentrating mechanism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The thin limbs of the loops of Henle in the mouse kidney have been investigated by conventional electron microscopy. Resulting from light microscopic investigations, a distinction in the epithelia of short and long loops can be demonstrated. Ultrastructurally, the thin limbs (descending) of short loops are composed of a uniformly thin and simple epithelium. In contrast, long loops (thin descending and ascending) are composed of three different epithelial types which are representative of a distinctly more complex epithelial system. Two epithelial types were observed in the thin descending limbs of long loops and the third type was observed in the ascending thin limbs. Based upon these findings it is suggested that the thin descending limbs of short and long loops of Henle in the mouse kidney cannot perform the same functions in the renal concentrating mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317960
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  • 72
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    The structure of the myosatellite cells in axial muscles of the sharkGaleus melastomus (1974)
    Springer
    Anatomy and embryology 147 (1974), S. 35-44 
    Details
    ISSN: 1432-0568
    Keywords: Myosatellite cells ; Shark ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The myosatellite cells in the axial muscles of the sharkGaleus melastomus is found more frequently in the red muscle fibers than in the white fibers. The total length of the cell extensions is about 100 μm. In about 20% of all cases, the extensions were present in pairs, and it is concluded that the satellite cell processes bifurcate. Processes towards the intercellular space and towards the interior of the muscle fiber are also described. The cytoplasm of the satellite cells contain glycogen, Golgi elements, lysosome-like vesicles, granular endoplasmic reticulum and microtubules. It is concluded that the morphology of the satellite cells indicates a more active function than that of a dormant reserve myoblast.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317962
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  • 73
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    Electronic Resource
    The fine structure of cerebral blood vessels in chick embryo (1974)
    Springer
    Acta neuropathologica 30 (1974), S. 277-285 
    Details
    ISSN: 1432-0533
    Keywords: Chick Embryo ; Brain ; Blood Vessels ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of the blood vessels was studied in the developing brain of chick embryo. The blood vessels were present in the embryos first examined (4 days after incubation) and their number increased in subsequent stages. The endothelial cells were generally large and showed junctional complexes, many microvilli and a large number of cytoplasmic organelles. Many tubular bodies and coated vesicles were also present. The tubular bodies were sometimes noted near the Golgi apparatus, suggesting their origin from this organelle. The mitochondria in the endothelial cells were generally larger than those in the surrounding neuropil. An ill-defined basement membrane-like substance was noted outside some endothelial cells on the 11th day and well formed basement membrane was present in the vessels of 18 day old embryos. A complete subpial astrocytic basement membrane was present from the early stage studied (4 days).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00697010
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  • 74
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    A comparison of the fine structure of small blood vessels in intracranial and retroperitoneal malignant lymphomas (1974)
    Springer
    Acta neuropathologica 27 (1974), S. 93-104 
    Details
    ISSN: 1432-0533
    Keywords: Malignant Lymphoma ; Blood Vessels ; Lymphe Node ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of the blood vessels of an apparently primary intracerebral malignant lymphoma was compared with those in another malignant lymphoma in a retroperitoneal lymph node. The essential features of the blood vessels in both cases were the same. They resembled the blood vessels found in normal lymph nodes and were both distinctly different from those seen in normal brain. It was concluded that the direction of differentiation of the blood vessels which arise to nourish the neoplastic tissue is determined by the nature of the tumor rather than the vessels from which they originate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687160
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  • 75
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    Electronic Resource
    Profound muscle weakness associated with axis cylinder ballooning (1974)
    Springer
    Acta neuropathologica 28 (1974), S. 87-92 
    Details
    ISSN: 1432-0533
    Keywords: Neuroaxonal Dystrophy ; Hallervorden-Spatz Disease ; Mitochondria ; Axonal Swelling ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Multifocal central white matter axonal swelling characterized electron microscopically by focal axonal mitochondrial and membraneous body enrichment occurred in a 52 year old man who presented with the chief complaint of severe progressive muscular weakness accompanied by disorientation. The clinical and pathological findings in this patient appear unique and are presented in order to broaden our concepts of axis cylinder pathology.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687522
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    Histochemistry and ultrastructure of atypical myoclonus body (type II) (1974)
    Springer
    Acta neuropathologica 28 (1974), S. 45-54 
    Details
    ISSN: 1432-0533
    Keywords: Myoclonic Epilepsy ; Atypical Myoclonus Body (Type II) ; Histochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Histochemical studies of type II myoclonus bodies demonstrated that they were composed of a saccharide-lipid complex with a small amount of protein. In particular, they contained phospholipid, ganglioside and sphingomyelin. The ultrastructure of the bodies revealed that they were bound by a membrane. They were diffusely stippled or homogeneous. They were not formed of filaments or lamellae. Some correlation with microbody or lysosomal structures in association with degeneration of the neurone was suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687517
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    Ultrastructure of the outer cortex and thepia mater in man (1974)
    Springer
    Acta neuropathologica 28 (1974), S. 79-86 
    Details
    ISSN: 1432-0533
    Keywords: Ultrastructure ; Human Outer Cortex ; Pia Mater
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The pia mater consists of a single, interrupted layer of elongated cells which lie fairly close to the surface of the cortex. Granular material and some collagen fibres lie between the pial cells and the cortex, a greater amount of collagen being present where the pial cells are discontinuous. Basement membrane covers the outer aspect of the cortex, the outer layer of which is formed by interlacing astrocyte processes of varying size. The processes are closely applied with occasional desmosomes between them. Projections of astrocyte processes of different dimensions covered by basement membrane extend at irregular intervals from the cortex into the subarachnoid space.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687521
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    Ultrastructure of the optic nerve in Schilder's disease, Devic's Disease and Disseminated Sclerosis (1974)
    Springer
    Acta neuropathologica 30 (1974), S. 225-242 
    Details
    ISSN: 1432-0533
    Keywords: Ultrastructure ; Optic Nerve ; Schilder's Disease ; Devic's Disease ; Disseminated Sclerosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of the optic nerve is described and compared in: a)Schilder's Disease, b)Devic's Disease, c)Disseminated Sclerosis. a) Schilder's Disease. Parts of the nerve were demyelinated, sometimes extensively so and from these regions the oligodendrocytes had disappeared and there was proliferation of astrocytes. Parallel bundles of fibres with a “railway line” formation, occurred in the cytoplasm of the astrocytes. Phagocytes infiltrated the damaged nerve bundles and the fibrous septa between them. Osmiophilic particles occurred in the astrocytes, capillary endothelial cells and in the phagocytes. The collagen fibres of some septa were widely separated presumably by fluid. b) Devic's Disease. This condition occurred in a patient with active pulmonary tuberculosis. The nerve was extensively demyelinated and showed absence of oligodendrocytes, proliferation of astrocytes and infiltration by macrophages. Some astrocytes possessed Rosenthal fibres. Intranuclear inclusions occurred in the astrocytes and electron dense cytoplasmic inclusions in the capillary endothelial cells and the macrophages. c) Disseminated Sclerosis. Parts of the nerve were partially and other parts completely demyelinated. Oligodendrocytes were absent from the completely demyelinated zones but were present in the partially demyelinated zones. In and around the demyelinated regions, there was proliferation of astrocytes and they frequently exhibited the “railway line” patterns in their cytoplasm. Phagocytes were frequent amongst the degenerating myelin and the proliferating astrocytes and also in the fibrous septa. Some macrophages presented intranuclear inclusions having a “corn on the cob” appearance.
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    URL: http://dx.doi.org/10.1007/BF00688923
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    Ultrastructure of cerebral vessels in chick embryo in lead intoxication (1974)
    Springer
    Acta neuropathologica 30 (1974), S. 287-294 
    Details
    ISSN: 1432-0533
    Keywords: Lead Toxicity ; Brain ; Cerebral Endothelium ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of cerebral vessels was studied at various stages of brain development in chick embryos exposed to lead intoxication when they were 4 days old. The endothelial cells showed swelling of mitochondria, presence of many cytolysosomal structures, many tubular bodies, and coated vesicles. A few vessels showed attenuation on the lining endothelial cells. The significance of these morphological alterations are discussed.
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    URL: http://dx.doi.org/10.1007/BF00697011
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    Electronic Resource
    Tubular structures in arachnoid cells (1974)
    Springer
    Acta neuropathologica 27 (1974), S. 363-368 
    Details
    ISSN: 1432-0533
    Keywords: Parallel and Concentric Tubules ; Arachnoid Cells ; Cerebral Glioma ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Parallel and concentric tubules were observed in the cytoplasm of arachnoid cells overlying cerebral gliomas. The parallel tubules were 400–500 Å wide. Their electron dense walls, 150 Å thick lay 200–250 Å apart with distensions up to 400 Å in diameter at irregular intervals between the walls. The walls formed terminal loops limiting up to 4 adjacent tubules; transverse extensions were present between adjacent walls. The tubules sometimes communicated with the rough endoplasmic reticulum from which they may possibly arise. The concentric tubules were 250 Å wide: they communicated at irregular intervals.
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    URL: http://dx.doi.org/10.1007/BF00690700
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  • 81
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    Une inclusion musculaire atypique rare: Les «corps en empreintes digitales» ou «fingerprint bodies» (1974)
    Springer
    Acta neuropathologica 27 (1974), S. 61-68 
    Details
    ISSN: 1432-0533
    Keywords: Muscular Pathology ; Ultrastructure ; Abnormal Muscular Inclusion ; Fingerprint Bodies ; Myofilament Synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary “Fingerprint bodies” are added to the “atypical” formations described in diseased muscle. These subsarcolemmal inclusions are variable in size and number, not membrane-bound and are formed by fine microtubules. They are not characteristic of a specific muscular disease and occur probably along with a focal anomaly of myofilament synthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00687241
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    Ultrastructural alterations of rat brain microglial cells and pericytes after chronic lead poisoning (1974)
    Springer
    Acta neuropathologica 28 (1974), S. 25-35 
    Details
    ISSN: 1432-0533
    Keywords: Chronic Lead Intoxication ; Rat ; Ultrastructure ; Microglia ; Pericytes ; Monocytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Wistar rats of both sexes and the same litter were exposed to chronic lead intoxication from birth untill sacrifice 9 months later. Lead was administered as 0.4% solution of lead nitrate in drinking water. Samples from the parietal brain cortex were examined electron microscopically following intracardiac perfusion with paraformaldehyde-glutaraldehyde solution. Similar changes were observed in the microglial cells and the vascular pericytes whereas all the other tissue elements appeared intact. Both cell types hypertrophied, the microglia assumed characteristic spindle or rod shape, the cell organelles increased, the microglial endoplasmic reticulum widened strongly and a large number of lipid inclusions appeared. The latter consisted of large lipid droplets of varying size and shape, containing multiple zones of low density, and a dense component with a coarse granular structure. The similarity in the response of both cell entities to the lesion as well as some probable functions of microglial cells and their relationship to vascular pericytes are discussed.
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    URL: http://dx.doi.org/10.1007/BF00687515
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    Fatal polymyositis: Morphogenesis and ultrastructural features (1974)
    Springer
    Acta neuropathologica 29 (1974), S. 251-262 
    Details
    ISSN: 1432-0533
    Keywords: Polymyositis ; Ultrastructure ; Histiocytes ; Birbeck Granules ; Macrophages
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A fatal case of polymyositis in a young female is presented. Two muscle biopsies obtained before and after treatment with large doses of steroids, as well as autopsy tissue, demonstrated widespread degeneration of myofibres associated with cytoplasmic tuboreticular structures resembling paramyxovirus nucleocapsids in capillary endothelial cells and fibroblasts. Aggregates of spherical particles and “simple and granular” nuclear bodies suggested a virus-related or associated etiologic agent. In addition, interstitial cells of mesenchymal origin, probably related to macrophages or histiocytes were present. These contained numerous rodlike profiles or phagolysosomal bodies which resembled “Birbeck” granules. Inflammatory response was very scant. It would appear that polymyositis probably represents a primary reaction to antigemic substances and a morphologic manifestation of altered host macrophage response.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00685260
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  • 84
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    A fine structural study on the extracellular activity of alkaline phosphatase and its role in calcification (1974)
    Springer
    Calcified tissue international 15 (1974), S. 201-212 
    Details
    ISSN: 1432-0827
    Keywords: Ultrastructure ; Alkaline Phosphatase ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des cals expérimentaux de neuf jours, formés au niveau de radius de jeunes rats, sont traités par la méthode calcium-cobalt de Gomori (1939) pour la mise en évidence ultrastructurale de la phosphatase alcaline afin d'étudier son rôle éventuel dans le dépôt du calcium. L'activité enzymatique apparait initialement sous forme de précipités globulaires en dehors de la membrane cellulaire de jeunes chondroblastes hypertrophiques. Ce précipité donne ensuite naissance à des corps sphériques de phosphatase alcaline qui se forme près de la cellule. Ces corps sphériques s'observent dans une zone intermédiaire plus éloignée. Une formation de cristaux en aiguilles (apparemment une calcification) se développe dans des corps isolés ou agrégés, laissant voir nettement leurs limites, même lorsque la calcification est plus avancée au point qu'on ne peut plus distinguer des cristaux individuels. Au niveau des coupes témoins, traitées de façon identique mais sans substrat ou avec de l'E.D.T.A., on n'observe ni précipité enzymatique ou corps sphériques. L'aspect des dépôts cristallins dans des corps qui contiennent de la phosphatase alcaline ne peut s'expliquer que par l'existence d'une association étroite entre enzymes et calcification.
    Abstract: Zusammenfassung Neun Tage alter experimenteller Kallus an Radii von jungen Ratten wurde mit Gomori's (1939) Calcium-Kobalt Methode untersucht, um die Verteilung der alkalischen Phosphatase und ihre Beziehung zur Calciumablagerung ultrastrukturell zu demonstrieren. Enzymaktivität zeigte sich zuerst als globulares Präzipitat außerhalb der Zellmembran von Knorpelzellen im Beginn der Hypertrophie. Aus dieser Präzipitatschicht entstanden dann gerundete Körperchen, die sich von der Zelle abtrennten. Solche Körperchen wurden auch in größerer Entfernung von der Zelle beobachtet, d.h. in einer Zwischenzone zwischen benachbarten Zellen. Nadelförmige Kristalle, wahrscheinlich von Calcium-Salzen, wurden in einzelnen oder aggregierten Körperchen beobachtet. Die äußere Zone der Körperchen blieb jedoch deutlich sichtbar, selbst dann, wenn der Calciumgehalt derart zugenommen hatte, daß einzelne Kristalle nicht länger erkennbar waren. In Kontrollen, die in gleicher Weise behandelt waren, aber ohne Substrat oder mit Zufügung von EDTA, wurden weder Präzipitate noch Körperchen beobachtet. Das Auftreten von Calciumablagerungen in alkalischer Phosphatase enthaltenden Körperchen scheint kaum anders erklärbar als durch eine enge funktionelle Verbindung zwischen Enzym und Calciumablagerung.
    Notes: Abstract Nine day old experimental calluses in radii of young rats were treated with Gomori's (1939) calcium-cobalt method to demonstrate ultrastructurally the presence of alkaline phosphatase in a search for its possible role in the desposition of calcium. Enzyme activity first appeared as globule-like precipitates outside the cell membrane of early hypertrophic cartilage cells. This precipitate layer then seemed to give rise to spherical bodies of alkaline phosphatase which occur at a slight distance from the cell. The spherical bodies were also observed further away from the cell in an intermediate zone between neighboring cells. Needle-like crystal formation, apparently calcification, occurred inside single or aggregated bodies, leaving their peripheral rim clearly visible, even when calcification had increased to such an extent that individual crystals could no longer be recognised. In controls, treated in the same way but without substrate, or with EDTA, no enzyme precipitate or spherical bodies were seen. The appearance of crystalline deposits in bodies which contain alkaline phosphatase seems difficult to explain on any other basis than that there is a close functional association between the enzyme and calcification.
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    URL: http://dx.doi.org/10.1007/BF02059057
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    Concordance between morphological and biochemical estimates of fluid spaces in rat brain cortex slices (1974)
    Springer
    Experimental brain research 21 (1974), S. 299-314 
    Details
    ISSN: 1432-1106
    Keywords: Brain cortex slices ; Ultrastructure ; Fluid spaces ; Swelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A comparison was made between morphological and biochemical estimates of extracellular and intracellular fluid spaces in rat brain cortex slices incubated under different conditions. By light microscopy the periphery of the slices was found to be more swollen than the center; this regional difference was verified biochemically in unfixed tissue. The electronmicroscopic evaluation of intra- and extracellular fluid spaces was accordingly based upon findings in a preselected area. Due to intracellular penetration of inulin in rat brain cortex slices the biochemically, determined extracellular and intracellular spaces were obtained by compartmental analysis of the inulin space. The concordance between the biochemical and the morphological findings was good: Both methods showed that the extracellular space increased during the incubation to a considerable magnitude after one hr. and that this extracellular space was reduced by excess potassium, glutamate, anoxia or incubation at 0°. Under the same conditions the biochemically determined intracellular space was increased. This cellular swelling was confirmed morphologically and found to comprise mainly glia cells after exposure to excess potassium, predominantly neurons after incubation at 0° and both cell types after anoxia or addition of glutamate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235749
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  • 86
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    Fenfluramine-induced ultrastructural alterations in tissues of rats and guinea pigs (1974)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 285 (1974), S. 175-184 
    Details
    ISSN: 1432-1912
    Keywords: Fenfluramine ; Rat ; Guinea Pig ; Phospholipidosis, drug-induced ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary After administration of the anorectic drug fenfluramine (40 mg/kg per day) to rats (s. c. or i. p.) and guinea pigs (p.o.) over periods of 2 to 11 weeks, electron microscopic examination was performed on lungs, liver, lymphatic tissues and peripheral blood of both species, and on adrenal glands and ovaries of rats. In rats, fenfluramine caused the following alterations (listed according to the duration of treatment): Formation of abnormal lamellated inclusions in lymphocytes and plasma cells of lymphatic tissues, appearance of “foam cells” in lung alveoli; formation of abnormal lamellated inclusions in corpus luteum, lymphocytes of peripheral blood, and in adrenal cortex. In guinea pigs, the same alterations were found in lymphocytes of spleen and peripheral blood, in hepatocytes and in lung. The present observations support the concept of a generalized phospholipidosis induced by amphiphilic compounds. The potency of fenfluramine to induce a lipidosis is, however, considerably less pronounced than that previously demonstrated for the anorectic drug chlorphentermine. This difference is suggested to be due mainly to the lower degree of amphiphilia of fenfluramine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00501152
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  • 87
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    Lipidosis-like ultrastructural alterations in rat lymph nodes after treatment with tricyclic antidepressants or neuroleptics (1974)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 286 (1974), S. 165-179 
    Details
    ISSN: 1432-1912
    Keywords: Lipidosis ; Antidepressants ; Neuroleptics ; Lymphocytes ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Lymphocytes of rat lymph nodes have previously been revealed as reliable and sensitive indicators of a particular drug side effect, notably a generalized phospholipidosis, inducible by a compound of amphiphilic character (chlorphentermine). The purpose of the present study was to examine the effects of other amphiphilic compounds upon rat lymphocytes. After oral administration of various tricyclic antidepressants (iprindole, imipramine, clomipramine, 1-chloro-amitriptyline, 1-chloro-10,11-dehydro-amitriptyline, noxiptiline, amitriptyline), or of two neuroleptic drugs (chlorpromazine, thioridazine) to rats, the popliteal lymph nodes were examined with the electron microscope. After a single application of either iprindole (50 mg/kg), imipramine (100 mg/kg), or clomipramine (150 mg/kg) small proportions of lymphocytes were found to contain abnormal lamellated cytoplasmic inclusions. The size and number of inclusions and the number of affected lymphocytes increased with further treatment. Similar observations were made after treatment with the chlorinated amitriptyline derivatives. On the other hand, only small numbers of lymphocytes were affected by noxiptiline, amitriptyline, chlorpromazine and thioridazine, even after prolonged treatments (up to 13 weeks) with high doses (up to 125–175 mg/kg). The present ultrastructural finding are interpreted as representing lipidosislike cellular alterations, yet of highly varying degrees. The large quantitative differences are tentatively suggested to be due to differences in the rate and mode of metabolism of the drugs, and due to differing degrees of amphiphilia of the compounds applied.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00501610
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  • 88
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    Wall ultrastructure ofScenedesmus culture N 46 (1974)
    Springer
    Archives of microbiology 96 (1974), S. 145-153 
    Details
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Scenedesmus Bristles ; Openings ; Props ; Ridges ; Tubules ; Brisble Origin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Bristles radiating from openings were detected on colonies and unicells ofScenedesmus culture N 46, when examined with transmission and scanning electron microscopes. Although narrower, they correspond in gross appearance and ultrastructure to previously describedScenedesmus bristles. Openings, bordered by a series of props, are unlike those ofScenedesmus culture 614. Additional props are observed scattered independently on the cell wall; ridges are composed of a linear row of props. Sections of cells, or cell walls, reveal an additional prop, situated inside the openings; these props are composed of several tubules. Possible extrusion of bristles through these tubules, as well as the origin of the bristle from the cavity and vesicles immediately under the opening are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00590171
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  • 89
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    Ultrastructural aspects of the marine fungusJaponochytrium sp. (1974)
    Springer
    Archives of microbiology 96 (1974), S. 305-317 
    Details
    ISSN: 1432-072X
    Keywords: Marine Fungi ; Ultrastructure ; Multilamellate Sporangial Wall ; Sagenogenetosome ; Zoospore Cleavage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The morphology and ultrastructure of aJaponochytrium sp. has been studied by light, scanning and transmission electron microscopy. The wall has been shown to be multilamellate and persistent. Stages in zoospore cleavage are described and sagenogenetosomes reported in mature sporangia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00590186
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  • 90
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    Cell wall formation in zoospores of Allomyces arbuscula (1974)
    Springer
    Archives of microbiology 98 (1974), S. 147-158 
    Details
    ISSN: 1432-072X
    Keywords: Allomyces ; Zoospores ; Cell Wall ; Wall Formation ; Lomasome ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Ultrastructural observations on encysting haploid zoospores of Allomyces arbuscula are presented with special reference to cell wall deposition. Multivesicular bodies are observed in the cytoplasm of zoospores 15 min after inoculation, lomasomes after 30 min and fine membrane profiles between the plasmalemma and the cyst wall are observed after 4 h indicating a possible system for secretion of cell wall components.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425277
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  • 91
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    A study of sporophore development in the myxomyceteProtophysarum phloiogenum (1974)
    Springer
    Archives of microbiology 99 (1974), S. 331-344 
    Details
    ISSN: 1432-072X
    Keywords: Myxomycetes ; Ultrastructure ; Development ; Systematics ; Food Vacuoles ; Stalk Development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Observations of sporophore development in fresh and glutaraldehydeosmium sequentially-fixed material ofProtophysarum phloiogenum show the following sequence. Small plasmodia cease streaming and round up. Food vacuoles collect in the lower center of the cytoplasmic mass. As the cytoplasm rises the food vacuolar contents are excluded from the plasmalemma and become the stalk core. A continuous, fibrous peridium and stalk tube enclose cytoplasm and stalk core respectively. Capillitial formation just precedes spore cleavage. Sporophore development is marked by autophagic activity and calcium deposition. Stalks of dried herbarium specimens of seven additional species have been examined. A mature stalk morphology very similar toProtophysarum with recognizable remnants of microorganismal food material is seen in all of them. It is thought that this marker is indicative of non-stemonitaceous stalk development.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00696247
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  • 92
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    An ultrastructural study of septal dissolution inSchizophyllum commune (1974)
    Springer
    Archives of microbiology 96 (1974), S. 175-182 
    Details
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Septa ; Schizophyllum ; Dissolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A strain ofSchizophyllum commune carrying a mutation in theB-mating factor (B-mut) shows septal dissolution when grown at 30° C for 2 to 3 days. The septa are intact if the organism is grown at 25° C for the same time, but begin to break down within 1 h after transfer to 30° C. At the ultrastructural level the dolipore swelling is the first part of the septal apparatus to be degraded, closely followed by the disorganization of the parenthesomes. A progressive thinning of the septal cross-wall produces an enlargement of the septal aperture sufficient to allow the passage of nuclei. It appears that degradative enzymes are probably carried to the site of septal dissolution in vesicles derived from endoplasmic reticulum in the area of the septal apparatus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00590174
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  • 93
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    Nitrogen metabolism and ultrastructure inAnabaena cylindrica (1974)
    Springer
    Archives of microbiology 96 (1974), S. 271-279 
    Details
    ISSN: 1432-072X
    Keywords: Anabaena cylindrica ; Nitrogen Starvation ; Pigmentation ; Ultrastructure ; Heterocyst Differentiation ; Nitrogenase Activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Nitrogen starvation, effected by incubating a culture ofAnabaena cylindrica in a medium free from combined nitrogen and under an atmosphere of 1% CO2 in argon, leads to rapid and characteristic changes in the appearance, structure and function of the alga. Change of colour, due apparently to a decrease in the amounts of nitrogenous pigments, is accompanied by a structural transformation of vegetative cells: cyanophycin granules and polyhedral bodies disintegrate, lipid and glycogen accumulate, and large membrane-bound spaces form by means of thylakoid swelling and vesiculation. The rate of heterocyst differentiation and nitrogenase activity is increased. These changes are fully reversed on addition of ammonia to the culture. It appears that thylakoids reform by coalescence of small vesicles assembled in the intrathylakoidal space. Rapid ammonia assimilation is indicated by ample formation of cyanophycin granules in vegetative cells and of “plugs” in the heterocysts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00590183
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  • 94
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    The presence of unusual microtubular structures in senescent cells of Chlamydomonas dysosmos (1974)
    Springer
    Archives of microbiology 98 (1974), S. 199-206 
    Details
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Chlamydomonas ; Senescent ; Microtubules ; Complexes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Complexes of twisted ribbons composed of ordered arrays of microtubules are identified in close association with the plasmalemma and the surfaces of some organelles in senescent cells of photoheterotrophically cultured Chlamydomonas dysosmos. The ribbon complexes occur throughout the cytoplasm, and do not appear related to the flagellar insertions. The component microtubules are approximately 26 nm in width, exhibiting a center-to-center spacing of about 44 nm. Additional cytoplasmic microtubules are often closely related to the tubular complexes. A detailed description of their fine structure is presented here which tends to support the ascribed function of microtubules in maintaining the structural integrity of the protoplasm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425282
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  • 95
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    Nitrogen metabolism and ultrastructure inAnabaena cylindrica (1974)
    Springer
    Archives of microbiology 99 (1974), S. 221-230 
    Details
    ISSN: 1432-072X
    Keywords: Anabaena cylindrica ; Molybdenum ; Vanadium ; Nitrogenase ; Ultrastructure ; Storage Products ; Heterocyst Frequency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The structural and functional symptoms of molybdenum deficiency inAnabaena cylindrica grown in a medium without combined nitrogen and thus dependent on fixation of elemental nitrogen, resemble those brought about by nitrogen starvation. However, the substantially increased rate of heterocyst differentiation in this culture is not accompanied by a corresponding increase in nitrogenase activity; on the contrary, enzyme activity is severely impaired in the absence of molybdenum. When the supply of molybdenum, or of ammonia, is restored, the alga recovers rapidly. Vanadium exerts an inhibitory effect upon nitrogen-fixing ability of the alga, and its presence in the molybdenum-deficient culture results in the amplification of the symptoms of mlybdenum deficiency.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00696236
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    Occurrence of microbodies in chloromonadophycean algae (1974)
    Springer
    Archives of microbiology 99 (1974), S. 265-269 
    Details
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Microbodies ; Vacuolaria ; Gonyostomum ; Chloromonadophyceae ; Chromophyta
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Microbody-like organelles occur in the cytoplasm of two chloromonadophycean algae,Vacuolaria virescens Cienkowsky andGonyostomum semen Diesing. Microbodies ofVacuolaria andGonyostomum have a granular matrix which lacks a crystalloid core; they are often present in close association with elements of the endoplasmic reticulum. The occurrence of microbodies in other algae is briefly reviewed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00696241
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  • 97
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    Die Leber bei der progressiven Myoklonusepilepsie (Lafora's disease) (1974)
    Springer
    Journal of molecular medicine 52 (1974), S. 559-567 
    Details
    ISSN: 1432-1440
    Keywords: Progressive myoclonus epilepsy (Lafora's disease) ; Type I (Unverricht, Lundborg) ; Type II ; Liver findings ; Clinical aspects ; Histology ; Ultrastructure ; Histochemistry ; Biochemistry ; Glycogenosis type IV ; Progressive Myoklonusepilepsie (Laforasche Erkrankung) ; Typ I (Unverricht, Lundborg) ; Typ II ; Leberbefunde ; Klinik ; Histologie ; Ultrastruktur ; Histochemie ; Biochemie ; Glykogenose Typ IV
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Dem klinischen Bild der progressiven Myoklonusepilepsie (Lafora's disease) liegt eine kongenitale Stoffwechselanomalie mit Ablagerung pathologischer Stoffwechselprodukte vorwiegend im Zentralnervensystem zugrunde. Der häufigere Typ I (Typ Unverricht, Typ Lundborg) zeigt eine regelmäßige Mitbeteiligung von Leber und Myokard sowie teilweise der Muskulatur, der seltenere Typ II ist mit seiner Speicherung nur auf das Zentralnervensystem beschränkt. Die Kenntnis der charakteristischen Leberbefunde kann einmal eine Hilfe sein für die klinische Unterscheidung von Typ I und Typ II, unspezifisch degenerativen Formen der Myoklonusepilepsie sowie gegenüber der myoklonischen Variante der amaurotischen Idiotie. Als eine weitere Möglichkeit könnte das bisher unbekannte Speicherprodukt und der auslösende spezifische Enzymdefekt auf diesem Wege identifiziert werden. Lichtmikroskopisch zeigen die Leberzellen — vorwiegend der Läppchenperipherie — und gelegentlich auch die Kupfferschen Sternzellen eine PAS-positive homogene Speichersubstanz, die in Übereinstimmung mit den Befunden am Zentralnervensystem und am Myocard elektronenoptisch aus granulärem und filamentärem Material aufgebaut ist. Die Deutung der einzelnen Untersucher hinsichtlich der histochemischen und biochemischen Ergebnisse variiert: die Natur des Ablagerungsproduktes wird als Mucopolysaccharid aber auch als Polyglucosan angesprochen. Übereinstimmend sieht man aber die Hauptstörung im Bereich des Kohlenhydratstoffwechsels. Die hier demonstrierten bemerkenswerten licht- und elektronenmikroskopischen Übereinstimmungen mit der Glykogenose Typ IV lassen nach unserer Auffassung nahe Beziehungen zur Gruppe der Glykogenosen annehmen. Als Thesaurismose ist die Laforasche Erkrankung eine potentielle Vorstufe der Cirrhose. Es entwickelt sich eine mehr oder minder ausgeprägte Mesenchymbeteiligung im Sinne einer chronischen Hepatitis. Eine komplette Cirrhose ist jedoch selbst bei den Spätfällen nicht nachzuweisen. Eine Hepatomegalie als Folge der Speicherung fehlt. Spezifische Leberproben fallen negativ aus. Das klinische Bild wird nicht von Seiten der Leber, sondern ausschließlich von der progredienten neurologisch-psychiatrischen Symptomatik der Myoklonusepilepsie geprägt.
    Notes: Summary The cause of clinical manifestations of progressive myoclonus epilepsy (Lafora's disease) is an inborn error of metabolism characterised by deposition of pathologic metabolic products in the central nervous system. In the most common type I (Type Unverricht, Type Lundborg) these deposits are regularly located in liver and myocard, and in some cases also in sceletal muscle. In the less common type II they are found only in the central nervous system. The characteristic liver findings might help to distinguish type I, type II, unspecific degenerative forms of myoclonic epilepsy and the myoclonic form of amaurotic idiocy. They also might be valuable in identification of yet unknown specific enzyme defect leading to tissue deposits. Our light microscopy observations demonstrate deposits of a PAS-positive homogene substance in liver cells—especially in the periphery of lobule— and sometimes in Kupffer cells. By electron microscopy this substance is identified as granular and filamentary material. This corresponds to our findings in the central nervous system and myocard. The interpretation of existing histochemical and biochemical studies did not yet solve the question, if the mentioned deposits are mucopolysaccharides or polyglucosanes, however, it is recognized that the main disorder is an error in carbohydrate metabolism. The notable similarity of our light- and electronmicroscopic observations to results obtained in glycogenosis type IV suggest that Lafora's disease might be another form of glycogenosis. As a thesaurismosis Lafora's disease can predispose to cirrhosis. The activation of mesenchyme, less or more pronounced, corresponds to chronic hepatitis. And even in the late forms a complete cirrhosis is not found. This thesaurismosis does not lead to hepatomegaly. Specific liver function tests are negative. The clinical course is characterised not by liver symptoms but by the neurologic and psychiatric symptoms of progressive myoclonic epilepsy.
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    URL: http://dx.doi.org/10.1007/BF01468496
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    The rotifer trap of Zoophagus (1974)
    Springer
    Archives of microbiology 101 (1974), S. 95-107 
    Details
    ISSN: 1432-072X
    Keywords: Zoophagus insidians Rotifer ; Predacious Fungi ; Oomycetes ; Glue Secretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The predacious watermold Zoophagus insidians traps loricate rotifers on short, lateral branches of the main, hyphal axis. These branches or “traps” are packed at their distal ends with a number of vesicles filled with an electron-dense matrix. Electron micrographs of the mycelium disclose a two-layered wall; the outer layer is electron dense and the inner, electron transparent. The outer dense layer on the tip of the “trap” is organized into a number of fine ridges and occasional discontinuities. Thin sections through recently trapped rotifers indicate that the cilia of the animals are stuck to the trap by a glue. This adhesive is derived from secretion of the matrix of the vesicles aggregated in the tip of the trap. The secretion mechanism is triggered by the animal and is accompanied by: 1. The separation of the two layers of the wall, 2. fusion of the vesicles with the cell membrane and 3. extrusion of the glue through pits in the tip of the inner wall of the “trap”. After snaring a rotifer, the previously arrested branch grows as a haustorium into the body cavity of the animal. The host tissues disintegrate within a few hours and appear to be the main nutrient source of the fungus.
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    URL: http://dx.doi.org/10.1007/BF00455929
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  • 99
    Electronic Resource
    Electronic Resource
    Ultrastructural aspects of localized membrane damage in Spirillum serpens VHL early in its association with Bdellovibrio bacteriovorus 109D (1974)
    Springer
    Archives of microbiology 100 (1974), S. 179-195 
    Details
    ISSN: 1432-072X
    Keywords: Bdellovibrio bacteriovorus ; Spirillum serpens ; Freeze Fracture ; Electron Microscopy ; Ultrastructure ; Membrane Damage ; Organismic Associations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The freeze-fracture technique and electron microscopy have been used to demonstrate that localized damage is inflicted upon the cytoplasmic membrane of Spirillum serpens VHL within 20 to 30 min after the start of its association with Bdellovibrio bacteriovorus 109D. This damage is not observed in uninfected Spirillum cells, nor in infected cells within the first 10 min. This damage takes the form of a “blister” which, when viewed stereoscopically in electron micrographs, is seen to project toward the interior of the Spirillum cell. Shortly after its formation, the blister becomes elaborated into a series of ridges which may assume forms ranging from an elaborate spiral to a series of loops or knots. The formation of a blister is shown to involve both the inner and outer leaves of the membrane bilayer, and evidence is presented to indicate that the blister site corresponds to the site of attachment of the Bdellovibrio cell. The hypothesis is proposed that this ultrastructural damage is the cytological basis for the controlled and localized leakage through the cytoplasmic membrane into the periplasmic space of the Spirillum cell at locations adjacent to the Bdellovibrio cell. It is suggested that this localized membrane damage may be the ultrastructural basis for the high efficiency with which bdellowvibrios are known to incorporate cytoplasmic materials from the other bacteria in whose periplasmic spaces they develop.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446316
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  • 100
    Electronic Resource
    Electronic Resource
    Comparative structural characterization of material extractable from aerial sheath of Streptomyces roseoflavus var. roseofungini (1974)
    Springer
    Archives of microbiology 101 (1974), S. 71-82 
    Details
    ISSN: 1432-072X
    Keywords: Streptomycetes ; Ultrastructure ; Surface Sheath
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Tubular-like structures were regularly revealed in the surface sheath of the aerial mycelium of the parent strain of Streptomycetes roseoflavus var. roseofungini. In their shape and dimensions these structures were highly reminiscent of those massive accumulation of which was earlier reported to occur in cultures of dedifferentiated nocardioform “fructose” mutant of the same parent strain. 2. The tubular-like structures of the aerial mycelium sheath were shown to be markedly susceptible to brief acetone washing, undergoing almost complete desintegration. 3. On addition of water to crude acetone extract of the aerial mycelium precipitation and possible selfassembly of a spectrum of various structures occurred (folded scaly, bubble-like, spout-like). Some among structures so produced were reminiscent of those found in spectra of structures observed in reconstruction experiments with tubules from the mutant as well as of structures found in the aerial sheath of the parent strain and some other actinomycetes. Similarity in subunit structure of above materials was also noticeable. The presence, in the sheath of aerial mycelium, of material with a tendency to selforganization is discussed in relation to the possible involvement of selfassembly processes in the formation of the surface sheath.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00455926
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