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  • 1985-1989
  • 1980-1984  (57)
  • 1975-1979  (126)
  • 1983  (57)
  • 1978  (126)
  • Electron microscopy  (183)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 401 (1983), S. 109-128 
    ISSN: 1432-2307
    Keywords: Clear-cell sarcoma ; Electron microscopy ; Immunohistochemistry ; Neural crest ; S-100 protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A clinico-pathological, light microscopic and immunohistochemical study of 15 clear-cell sarcomas, with an ultrastructural analysis of 6 of the tumors, is presented. The tumors showed a strong predilection for tendons and aponeuroses of the extremities in predominantly young and middle-aged people. The clinical setting, course and light microscopic appearance agree well with the original description by Enzinger (1965). Nine of the 15 patients developed metastases, most of them including lymph nodes, and 8 of the patients had died at the time of follow-up (median follow-up time 4.8 years). Reducing pigment was demonstrated within the cells of 2 tumors. Ultrastructurally the 6 tumors studied had a uniform appearance with characteristically rounded or oval tumor cells with a single nucleus containing one or two very prominent nucleoli, a light-staining cytoplasm with a moderate amount of organelles and a variable content of glycogen. Polymorphic melanosomes were seen in the cells of one of the tumors. External laminas enclosed groups of tumor cells and invested parts of individual tumor cells. With immunoperoxidase analysis for S-100 protein positive staining was observed in the vast majority of the tumor cells of all 15 clear-cell sarcomas. Metastases appearing in 9 of the 15 cases showed positive staining for S-100 protein. There was a strong staining of the cytoplasm and generally a weak and varying staining of nuclei. The immunohistochemical and electron microscopic findings indicate that clear-cell sarcoma is a homogenous entity among soft tissue sarcomas, of probable neural crest derivation.
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  • 2
    ISSN: 1432-1335
    Keywords: Murine lymphoma development ; Virus infection ; Thymus ; Reticular epithelial cells ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This report describes two types of reticular epithelial cell in the thymic cortex of the BALB/c mouse, an immature and a mature form. During early stages of lymphoma development, i.e., 2–6 weeks postinfection (p.i.) with Moloney leukemia virus (M-MuLV), activation of the epithelial cells is observed. Although the percentage of these cells in the total cell population of the thymic cortex remains constant during that time, the number of mature epithelial cells is significantly increased in infected animals. Subsequently, about 6 weeks p.i., the number of immature epithelial cells starts to increase, whereas the number of mature reticular epithelial cells declines and the appearance of the mature epithelial cells changes drastically. The results of light and electron microscopic studies indicate degeneration of the mature reticular epithelial cells at the onset of lymphoma development at a time when the first deficiencies in the immunologic competence of the reticular epithelial cells are apparent.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Journal of cancer research and clinical oncology 106 (1983), S. 234-239 
    ISSN: 1432-1335
    Keywords: Osteosarcoma ; Collagen types ; Immunofluorescence microscopy ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Sixteen cases of typical highly malignant osteosarcoma were investigated by light, electron, and immunofluorescence microscopy to demonstrate the presence of collagen types I–III. It was shown that, in light-microscopically anaplastic areas of the tumor, collagen type III predominates, while only very few membranes of collagen type I are observed. Ultrastructurally, the cells are characterized by numerous free ribosomes in their cytoplasm and only a few membranes of granular endoplasmic reticulum (ER). In osteoblastic areas, collagen type I is increased, while type-III collagen is decreased. The cytoplasm of cells contains markedly more granular ER. An increasing mineralization of matrix is observed. In fibroblastic areas of the tumors, collagen types I and III are codistributed. Tumor cells have a fibroblast appearance with elongated nuclei and well developed granular ER. The chondroblastic areas, characterized by immature neoplastic cartilage, contain varying amounts of collagen type II. Chondroblast-like tumor cells have typical ring-shaped membranes of granular ER in their cytoplasm. The evidence of different collagen types in osteosarcomas lends additional support to the concept that a pluripotent mesenchymal cell is the stem cell of osteosarcomas.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 400 (1983), S. 119-142 
    ISSN: 1432-2307
    Keywords: Thyroid neoplasms ; Hemangioendothelioma ; Electron microscopy ; Factor VIII-related antigen (FVIIIRAG) ; Tumour classification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 65 cases of hemangioendothelioma (HE) of the thyroid were accepted as such after control of slides of surgical or autopsy specimen or both. In a few of the more recent cases material could be examined by electron microscope and in some the search for factor VIII-related antigen (FVIIIRAG) was carried out. The demonstration of Weibel-Palade bodies in tumour cells in two cases and the evidence of FVIIIRAG in tumour cells of at least two cases, including primary tumour and distant metastasis, finally show, that the hemangioendothelioma of the thyroid is not simply an anaplastic carcinoma with some peculiar features; at least some of these tumours are true endotheliomas. The proposal that the term hemangioendothelioma be eliminated from the classification of thyroid tumours is therefore unfounded.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 400 (1983), S. 187-199 
    ISSN: 1432-2307
    Keywords: Malignant fibrous histiocytoma ; Liposarcoma ; Sarcoma ; Soft tissue neoplasms ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ultrastructural comparison of 7 examples of myxoid malignant fibrous histiocytoma (myxoid MFH) with 6 of myxoid liposarcoma is described. Despite certain histological differences between the two, electron microscopy was more valuable in differentiating MFH from liposarcoma. Electron microscopically, MFH contained a variety of cell types including histiocyte-like, fibroblast-like, intermediate-type, xanthomatous, multinucleated tumor giant cells and undifferentiated cells. Liposarcoma was composed mainly of lipoblasts at various stages of differentiation with a minority of undifferentiated cells and fibroblast-like cells. In contrast to the component cells of the MFH, these lipoblasts were characterized by abundant cytoplasmic glycogen, numerous pinocytotic vesicles and a discontinuous basal lamina in addition to large lipid droplets.
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  • 6
    ISSN: 1432-2307
    Keywords: Cystitis ; Electron microscopy ; Vasculitis ; Elastic tissue ; Autoimmune diseases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Bladder vessel walls of 20 patients with interstitial cystitis were studied by the electron microscope. 14 (70%) had severe endothelial injury. 10 (50%) showed injured smooth muscle cells. Odd basement membrane proliferations and disruptions were seen. Clusters of microfibrils about 10 nm in diameter and numerous partially membrane-bound vesicles of 100–600 nm with granular or tiny vesicular content (“granulovesicular bodies”) were also seen. Intercellular junctions of endothelial cells were open and there was emigration of polymorphonuclear leucocytes and platelets. The findings show pronounced vascular injury to have taken place, with neoformation of elastic tissue. It is suggested that the injury is immunologically mediated and that particularly those clusters of connective tissue microfibrils not yet covered by an amorphous elastin component may be involved in the pathogenesis of this disease.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 400 (1983), S. 97-106 
    ISSN: 1432-2307
    Keywords: Tracheobronchial amyloidosis ; Electron microscopy ; Amyloid fibril ; Fibroblast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The author reports on the electron-microscopic examination of the diffuse tracheobronchial amyloidosis of a 51-year-old patient. The amyloid deposits were located in the lamina propria of the tracheal and bronchial mucosa. At the edge of the nodular deposits, condensation and radial arrangement of amyloid fibrils could be seen. Closely connected with the amyloid, active fibroblasts were present and their cytoplasm contained amyloid fibrils. The cell membrane of the fibroblasts was missing in part. Intracellular amyloid fibrils mingled with extracellular deposits. It can be assumed that active fibroblasts play an important role in local amyloid formation.
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  • 8
    ISSN: 1432-2307
    Keywords: Mycosis fungoides ; Premycotic lesions ; Parapsoriasis en Plaques ; Langerhans cells ; Virus-like particles ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Skin biopsies of patients with small and large plaque parapsoriasis, premycotic lesions and mycosis fungoides in different stages were examined. Special attention was paid to the relationships between Langerhans cells (LC) and the neighbouring keratinocytes and lymphocytes. At the contact areas of LC and keratinocytes as well as LC and lymphocytes, particular cell membrane phenomena were observed. Aggregations of Langerhans granules and fusions of granules with LC plasma membranes were found exclusively at LC-keratinocyte interfaces. At LC-lymphocyte contact zones cell membrane appositions were seen. In all cases investigated, virus-like particles were mainly ound in LC and indeterminate cells (IDC). In 3 cases lymphocytes also contained these particles. It was of particular interest that virus-like particles were observed in skin specimens of all diseases investigated. Discrimination of these particles from other cellular organelles - especially lysosomes- was difficult, however. The significance of our findings, particularly regarding to the supposed virus aetiology of cutaneous T cell lymphomas, is discussed.
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  • 9
    ISSN: 1432-069X
    Keywords: Pityriasis rubra pilaris ; Histochemistry ; Autoradiography ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Five patients with pityriasis rubra pilaris (PRP) were analyzed by means of light and electron microscopy as well as by histochemistry and autoradiography. The results were compared with findings in psoriasis vulgaris. In PRP we found a moderate increase of the labeling index of epidermal cells, a highly increased labeling index of dermal infiltrating cells, and a mild spongiosis, and in the stratum granulosum, a decreased number of tonofilaments and an increased number of keratinosomes. The horny layer in PRP showed a pronounced histochemical and electron microscopical parakeratosis, even when histological parakeratosis was absent. In contrast with psoriasis vulgaris, there was no exocytosis of polymorphonuclear leucocytes into the epidermis, the papillomatosis index was normal, and there were no tortuous capillaries in the dermal papillae. The stratum granulosum was always present and sometimes thickened, showing electron microscopical changes different from those referred to in psoriasis. These changes point to a relatively distinct pattern of epidermal changes in PRP.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Archives of dermatological research 275 (1983), S. 407-411 
    ISSN: 1432-069X
    Keywords: Langerhans cell ; ATPase ; Ia-like antigen ; OKT6 ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 59 (1983), S. 139-144 
    ISSN: 1432-0533
    Keywords: Decompression sickness ; Brain ; Gas bubbles ; Blood-bubble interface ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Rats were exposed to 6.1 bar (abs.) air for 90 min and subsequently decompressed to the ambient pressure. After a decompression rate of 6.8 bar/min pial veins and superior sagittal sinuses were found to contain gas bubbles; no intravascular bubbles were observed subsequent to a decompression rate of 1.5 bar/min. Under the electron microscope platelet aggregates were observed at both the electron-dense layer of the blood-bubble interface and in pial veins with no bubbles. It is concluded that during decompression sickness bubbles and both activation and aggregation of platelets occur in intracranial veins. Subsequent venous congestion may contribute to the neuronal lesions and symptoms of acute decompression sickness.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 59 (1983), S. 246-254 
    ISSN: 1432-0533
    Keywords: Muscle spindle ; Electron microscopy ; Terminal nerves ; Denervation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intrafusal and extrafusal nerve segments in muscle spindles from tumbricalis muscles of the hind-paw of the rat were studied by electron microscopy from 10h to 5 days after severance of the sciatic nerve. In several spindles examined, nerve fascicles piercing the spindle capsule in the equatorial region contained a large myelinated, a smaller myelinated and an unmyelinated fiber. Unmyelinated fibers were not present in small fascicles leading to the polar region. The changes in the extrafusal nerve segments followed the pattern of Wallerian degeneration. Intra-axonal glycogen deposits were prominent in sensory fibers. The unmyelinated fibers were the earliest to degenerate, the large myelinated ones the latest. Differences between motor and sensory fiber degeneration emerged in their preterminal intrafusal segments and were analogous to those of the nerve endings. Terminal nerve fibers in the spindle equator succumbed to attack of mesenchymal cells, leaving extensive basement membrane reduplications around myelin debris-laden Schwann cells, while polar fibers were engulfed by Schwann cell processes, leaving regular bands of Büngner.
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  • 13
    ISSN: 1432-0568
    Keywords: Electron microscopy ; Mesonephric duct ; Fetus ; Glycogen ; Human development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Human mesonephric duct epithelial cells contained empty appearing regions in the infranuclear cytoplasm when prepared for transmission electron microscopy using glutaraldehyde and osmium fixation. The same regions stained positively with PAS in Epon sections for light microscopy suggesting that glycogen was present. Incubation with saliva abolished the reaction. For electron microscopy the glycogen stained very intensely if a mixture of osmium tetroxide and potassium ferrocyanide was used instead of osmium alone. Glycogen accumulations were present between the ages of 5 to 10 weeks and absent at the age of 15 weeks. Reports by others indicate that glycogen may be present in different reactive forms in relation to its staining behaviour after various fixatives. The present results, and similar studies in other tissues, indicate that osmium tetroxide-potassium ferrocyanide fixative should be used routinely for preservation of embryos and fetuses and where indicated, for ultrastructural identification of glycogen and cytoplasmic filaments in clinical specimens.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 59 (1983), S. 295-303 
    ISSN: 1432-0533
    Keywords: Menkes' kinky hair disease ; Brain degeneration ; Mitochondrial abnormalities ; Distribution ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The brain of an autopsy case of Menkes' kinky hair disease (MKHD), after routine histological examination, was studied extensively by electron microscopy, particularly the mitochondrial alterations. There were widespread mitochondrial abnormalities, including enlargement with tubulo-vesiculated cristae, swelling, and dense body formation and occasional accumulation of glycogen within mitochondria, in addition to increased numbers of mitochondria in some neurons. These abnormalities of mitochondria were present in decreasing severity in the following: Purkinje cells, neurons of the molecular and granule cell layers of the cerebellum, and neurons of the cerebral cortex, globus pallidus, lateral nuclei of the thalamus, caudate nucleus, and the myelinated axons in the white matter. This distribution and the degree of mitochondrial abnormalities in the various structures of the brain were compared with those of degenerative lesions in the respective structures. The comparison disclosed that there was a positive correlation between the two. The mitochondrial enlargement and swelling as in the present study had been well documented in the brain of the brindled mouse; mitochondrial dense bodies had also been reported in previous case reports of MKHD by other authors. The present study strongly suggests that the mitochondrial disease is an essential abnormality and may be responsible for the progressive degeneration of the CNS in MKHD.
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  • 15
    ISSN: 1432-0533
    Keywords: Human sural nerve ; Electron microscopy ; Myelin sheath thickness ; Internodal length ; Node of Ranvier ; Organic solvents ; Glycogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ultrastructural and morphometric study was performed on sural nerve biopsies of four industrial spray painters (35–59 years) and 11 controls (6–64 years). No difference could be shown in spray painters and age-matched controls as to the number of myelinated nerve fibres per area, their size distribution, variation of internodal length along single nerve fibres or the ratio between the number of myelin lamellae and the axon circumference. There was marked scattering of the two latter parameters in older exposed and control individuals. The distribution of NADH2-tetrazolium reductase activity was similar in exposed and control cases. The general ultrastructural appearance of nodal-paranodal regions in controls conformed with that noted in experimental animals. The overall ultrastructural organization and age-related changes of nerves of exposed cases were similar to those of control cases except for a presence of paranodal axonal mitochondria which contained glycogen-like particles in exposed cases. In one exposed case abundant dispersed or clustered glycogen-like particles were seen in the paranodal axoplasm. These findings are suggested to be an effect of chronic exposure to organic solvent vapours. Ageing seems, however, to have a much greater impact on the morphology of the sural nerve fibre than occupational exposure to organic solvent.
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  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 60 (1983), S. 309-313 
    ISSN: 1432-0533
    Keywords: Hirano bodies ; Extraocular muscle ; Aging ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Thirty-three rectus superior extraocular muscles from 23 autopsy cases, all over 60 years, were examined. Eosinophilic inclusions (Hirano bodies) were observed in all the muscles; they were stained deep red by Masson's trichrome stain and were positive for protein stain. They consisted of a collection of filamentous structures of two types: (1) a regular array of filaments 100 Å in diameter which sometimes were arrayed in perpendicular planes and (2) another type in a herring bone or ladder-like pattern. Both structures were closely associated with the accumulated thin filaments 50–60 Å in diameter (actin?) in the subsarcolemma. The frequent appearance in aged muscle fibers of Hirano bodies indicates that their formation is a change closely related with aging.
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  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 61 (1983), S. 116-122 
    ISSN: 1432-0533
    Keywords: Methylmercury ; Mitochondria ; Cerebral cortex ; Postnatal development ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Neonatal rats received s.c. injections of methymercuric chloride (MeHg) in physiological saline (1.5 mg Hg/kg b.wt.) at 48-h intervals from postnatal day 2 to day 50. Littermate controls were injected with an equivalent volume of saline. All animals were perfused on day 51 and blocks of cerebral cortex were prepared for electron microscopy. Ultrastructural changes in mitochondria were evident in the dendrites, axons and presynaptic terminals of cortical neurones in the MeHg-treated animals. Many mitochondria were condensed with an increased electron density of the inner matrix. Some profiles exhibited regressive alterations, including a disruption of cristae and the inner membrane with an accumulation of electron-opaque material in the matrix. Membranous whorls were found in association with the most degenerate mitochondria. A morphometric analysis of mitochondrial profiles in the neuropil of layer I revealed a 24% decrease in average profile area and a 16% increase in the number of profiles per micrograph in the MeHg-treated animals. These pathological changes in mitochondrial ultrastructure are consistent with an inhibition of mitochondrial respiration. The observed increase in the number of mitochondrial profiles may reflect a compensation by cortical neurons for the reduced efficiency of aerobic metabolism in the individual organelle.
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  • 18
    ISSN: 1432-0983
    Keywords: Allomyces macrogynus ; Mitochondrial DNA ; Electron microscopy ; Restriction enzyme map
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The mitochondrial (mt) DNA of the aquatic phycomycete Allomyces macrogynus is a circular molecule with a size of 56.1 kbp. The cleavage sites for the restriction enzymes SalI and PvuI were mapped by comparing the partial denaturation patterns of isolated restriction fragments with the pattern of the intact circle. The genes coding for the small and large ribosomal RNA (rRNA) were located on the restriction map by heteroduplex and R-loop analysis. The gene coding for the large rRNA contains an intervening sequence, app. 0.7 kbp in size, near the 3′-end of the gene. The two rRNA genes are encoded on the same strand of the mtDNA and separated by a region of 17–18 kbp. This rRNA gene organization is similar to that found with members of the Ascomycetes.
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  • 19
    ISSN: 1432-0738
    Keywords: Cadmium ; Toxicology ; Electron microscopy ; Endothelium ; Liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract With quantitative techniques at electron microscopical level chromatin condensation and emptying of the interchromatin space have been established in the nuclei of the endothelial cells of small uterine vessels. The nuclear and cytoplasmic changes after cadmium administration show much similarity between endothelial cells of small uterine vessels and cultured liver parenchymal cells. Cytoplasmic changes in both cell types after cadmium administration are suggestive of a disturbance in ribosomal RNA synthesis as the main cause leading to ultimate cell lysis.
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  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Archives of toxicology 53 (1983), S. 151-163 
    ISSN: 1432-0738
    Keywords: Fenofibrate ; Human liver ; Electron microscopy ; Morphometry ; Peroxisomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In rodents fenofibrate shares with other triglyceride-lowering agents the potential to increase the liver peroxisome population. It was therefore of interest to look for this effect in hyperlipoproteinemic patients receiving this drug. Light and electron microscopy of liver biopsies from a group of 10 patients treated with fenofibrate and from another group of 15 receiving diet only, show no morphological difference between both groups. In contrast with the rodent data the morphometric study reveals no significant changes in the number (fenofibrate group: 7.96 1010 cm−3; group receiving diet alone: 8.41 1010 peroxisomes/cm3 of liver tissue) or in the size (fenofibrate group: Diameter=0.53±0.07 μm — group receiving diet alone: 0.50±0.06) of peroxisomes. The difference between our results and those obtained consistently in rodents may be due to the relatively low dose in man and/or a species-dependant difference in enzyme content of liver peroxisomes, itself related to an apparent difference in the way in which lipids are handled.
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  • 21
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    Electronic Resource
    Springer
    Archives of dermatological research 275 (1983), S. 156-158 
    ISSN: 1432-069X
    Keywords: Sarcoidosis ; Fcγ-receptors ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Immune complexes of horseradish peroxidase (HRP) and rabbit IgG antibodies to HRP were used to study the Fcγ-receptors in granulomas of cutaneous sarcoidosis. Cryostat sections of skin biopsies were incubated with HRP-anti-HRP, and the peroxidase activity was demonstrated with 3,3-diaminobenzidine tetrahydrochloride and H2O2. Most cells in the granulomas, both epithelioid and giant cells, were stained. By electron microscopy, the reaction products were localized to the plasma membranes of the cells as well-defined granular deposits. No reaction product was demonstrated intra- or extracellularly.
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  • 22
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    Archives of microbiology 135 (1983), S. 25-29 
    ISSN: 1432-072X
    Keywords: Electron microscopy ; Euglena mutabilis ; Flagellate ; Photomovement ; Photoreceptor ; Phototaxis ; Single-cell analysis ; Videomicroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Due to the lack of an emergent flagellum the green flagellate Euglena mutabilis is restricted to gliding motility. During forward movement, the organisms orient positive phototactically in the presence of a suitable light stimulus. The cell contains both a stigma and a paraflagellar body which differ in shape and size from the organelles found in E. gracilis. The degree of orientation in white light follows an optimum curve with a maximum at about 100 lx. The spectral sensitivity shows a number of prominent peaks in the blue and green regions and extends well into the red region of the visible spectrum. Since the cell does not rotate during locomotion a periodic shading mechanism cannot account for phototactic orientation. Thus, phototaxis in the related species, E. gracilis and E. mutabilis differ in their photoreceptor molecules, their sensory transduction chains and their strategies of light direction detection.
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  • 23
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    Archives of microbiology 135 (1983), S. 169-175 
    ISSN: 1432-072X
    Keywords: Photosynthetic membranes ; Electron microscopy ; Image processing ; Ectothiorhodospira halochloris ; Ectothiorhodospira abdelmalekii ; Rhodopseudomonas viridis ; Rhodopseudomonas sulfoviridis ; Thiocapsa pfennigii
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The photosynthetic membranes of the five bchl b-containing bacteria Ectothiorhodospira halochloris, E. abdelmalekii, Rhodopseudomonas viridis, R. sulfoviridis and Thiocapsa pfennigii have been investigated by electron microscopy and digital image analysis. All five species have the photosynthetic complexes hexagonally arrayed in the membrane with lattice spacings close to 13 nm, except for R. sulfoviridis and T. pfennigii which display somewhat smaller (∼12.5 nm) lattice spacings. Correlation averaging which imposes less stringent requirements on the lattice perfection than conventional Fourier filtration techniques has been employed to elucidate the structure of the photosynthetic complexes. Their basic organization, i.e. a ring, probably containing the light-harvesting (LH) polypeptides, surrounding a core (the “reaction centre”) appears to be almost identical for all species under scrutiny. Despite a resolution of ∼1.6 nm, however, little further significant substructure can be deduced from the averages; possible reasons for the “blurred” appearance of the LH-ring and absence of any subdivision in the reaction centre are discussed along with strategies aimed at obtaining a more detailed model of the molecular architecture of the photosynthetic membranes.
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  • 24
    ISSN: 1432-0584
    Keywords: Multiple myeloma-Plasma cell ; Electron microscopy ; Fluorescent antibody technique
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of “nonsecretory” myeloma is described. The patient had typical osteolytic lesions and marked infiltration of myeloma cells in the bone marrow, and plasma cell leukemia. A good partial remission was obtained with Melphalan, but the patient relapsed and died one year later. Immunofluorescent and immunoelectroscopic studies on the myeloma cells demonstrated the presence of cytoplasmic γ-and κ-chains at the initial stage and of only κ-chains at a relapse. The electron microscopic method for polysome analysis indicated that both L-and H-chains were synthesized on membrane-bound polysomes initially, but the ability to produce H-chain was missing at the relapse.
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  • 25
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    Annals of hematology 47 (1983), S. 13-19 
    ISSN: 1432-0584
    Keywords: Acute lymphoblastic leukemia ; Intracytoplasmic inclusions ; Mitochondria ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A patient with acute lymphoblastic leukemia (ALL) with cells containing two types of cytoplasmic inclusions is described. The inclusions appeared as glubular bodies containing electron dense material with homogenous structure and as crystalloid formations confined in organelles with structure similar to that of the surrounding mitochondria. In distinction to other reports, these structures were not related to the endoplasmic reticulum. The possibility that some of them represented altered mitochondria is discussed.
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  • 26
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    Colloid & polymer science 261 (1983), S. 373-374 
    ISSN: 1435-1536
    Keywords: Electron microscopy ; short-time staining ; nodular structure ; crystallization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 27
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    Journal of molecular medicine 61 (1983), S. 593-599 
    ISSN: 1432-1440
    Keywords: Small intestine ; Early ischemia ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The morphology and chronology of an absolute ischemia was investigated on the small intestine of man and rat. It could be shown that the morphogenesis of ischemic damage to the intestinal mucosa in man does not differ from that in the rat. However, there are crucial and in therapeutic terms significant differences in the time course of the ischemic damage to the intestinal mucosa. Whereas in the small intestine of the rat, the first appreciable alterations — detachment and disruption of the lining epithelium at the villous tip — are already to be observed after absolute ischemia lasting 15 min, in the human small intestine the same lesions only occur after 4 h. A comparable complete necrosis of the small intestinal mucosa was detected in the rat after 7-h ischemia, and in man after 44-h ischemia.
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  • 28
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    Journal of cancer research and clinical oncology 105 (1983), S. 285-291 
    ISSN: 1432-1335
    Keywords: Borderline lesion ; Severe dysplasia ; Gastric precancerosis ; Electron microscopy ; Morphometric analysis ; Bleb formation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The “borderline lesion” of the stomach (severe dysplasia of the protruded type) is nowadays considered to be a true precancerous lesion. Histologically, this lesion is characterized by a proliferation in the area of the glandular neck, combined with severe cellular atypia. Investigation by means of transmission electron microscopy reveals the structure of these cells to be very similar to the structure of cells of an intestinal-cell-type carcinoma of the stomach. In addition to signs for a loss of differentiation of the cells, such as the absence of rough-surfaced endoplasmatic reticulum, mucin granules, and of the polarity of the cells, remarkably frequently luminal bulges and “blebs” developed to various extents can be detected. Morphometric analysis is delineating the tendency of structural features of the borderline lesion to develop toward the gastric cancer cell. These irregularities might be expressions of the beginning of expansive growth and signs pointing to differentiation into malignant neoplasia.
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  • 29
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    Acta neuropathologica 60 (1983), S. 149-152 
    ISSN: 1432-0533
    Keywords: Adrenoleukodystrophy ; Cerebello-brainstem involvement ; Electron microscopy ; Biochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of adrenoleukodystrophy was studied morphologically and biochemically. The patient was a 28-year-old man with no family history of adrenoleukodystrophy. His neurologic symptoms were cerebellar ataxia, spastic paraplegia, pseudo-bulbar palsy, and a minimal visual disturbance, with neither adrenal nor hypogonadal symptoms. The morphological and biochemical findings in this case are identical with those in typical adrenoleukodystrophy, but the topographical distribution of the lesions is distinctly different. The changes selectively affect the white matter in the cerebellum and brain stem in contrast to minimal involvement of the occipital white matter.
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  • 30
    ISSN: 1432-0533
    Keywords: Motor end-plates ; Abnormal differentiation of motor end-plates ; Arthrogryposis ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The syndrome of arthrogryposis and palatoschisis (SAP), an inherited syndrome of muscular hypotonia in Charolais cattle, was used as an experimental model to study neuromuscular differentiation. The ultrastructural development of muscle, peripheral nerve, and neuromuscular junctions was studied to determine the sequence of events preceding hypotrophic changes in the skeletal muscles of affected calves at birth. Dorsiflexion of the metatarsophalangeal joints in the hindlimbs occurred in fetuses older than 3 months of age, but hypotrophic changes in skeletal muscle, manifested as small fibers scattered among larger and occasional degenerating fibers, was not apparent until late in gestation, affecting 8-month-old fetuses and neonatal calves. Electron microscope and enzyme histochemistry studies disclosed differentiation of skeletal muscle into fiber types which is consistent with changes expected from disuse and does not indicate a primary myopathic abnormality. Abnormal differentiation of neuromuscular junctions (NMJ), composed of several separated axonal endings terminating in shallow synaptic gutters, indicated impaired maturation of the synapse. The earliest indication of abnormal NMJ was observed in a 5-month-old SAP fetus. The clinical signs and pathologic changes found in the neuromuscular junction and skeletal muscle of SAP fetuses are consistent with an embryologic defect occurring during development of the central nervous system (CNS) that affects the integrated function of the motor neurons to the limbs. However, diversification of myofibers by histochemistry and ultrastructural parameters is evidence that the intrinsic physiologic properties of spinal motor neurons were retained.
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  • 31
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    Acta neuropathologica 60 (1983), S. 14-18 
    ISSN: 1432-0533
    Keywords: Rathke's cleft cyst ; Craniopharyngioma ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The electron-microscopical appearance of a Rathke's cleft cyst is described. The cyst lining is seen to consist predominantly of secretory columnar epithelium, both ciliated and non-ciliated. There are also epidermoid cells occurring singly or in squames. The histogenesis of Rathke's cleft cysts, in relation to craniopharyngiomas, is discussed.
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  • 32
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    Acta neuropathologica 60 (1983), S. 271-277 
    ISSN: 1432-0533
    Keywords: Tuberous sclerosis ; Subependymal giant-cell tumor ; Immunohistochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Tissue from seven patients with tuberous sclerosis and subependymal giant-cell tumors was examined with special stains, immunohistochemistry, and electron microscopy. Immunoreactive glial fibrillary acidic protein (GFAP) was not found in the giant cells of four tumors, but was present in some tumor cells in the other three. Immunoreactive S-100 protein was present in tumor cells of six cases; it was also seen in more tumor cells than was GFAP. Electron microscopy was similar in all cases and showed that the tumor cells had numerous organelles — many dense bodies thought to be primary lysosomes, swollen mitochondria, Golgi complexes, rough and smooth endoplasmic reticulum, free ribosomes, and sparsely distributed intermeadiate filaments. In one case, neurosecretory granules, microvilli, and synapses were observed. In another subject, prominent, thick bundles of glial filaments were seen. These findings suggest that the tumor is made up of unique cells in addition to cells with recognizable neuronal or astrocytic features.
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  • 33
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    Cell & tissue research 230 (1983), S. 639-648 
    ISSN: 1432-0878
    Keywords: Non-adrenergic, non-cholinergic autonomic nerves ; Quinacrine ; Fluorescence microscopy ; Electron microscopy ; Anococcygeus muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphological changes induced in the autonomic nerves of the rat anococcygeus muscle after the injection of quinacrine (QC, 100 or 200 mg/kg) were examined by electron microscopy in order to clarify the nature of QC-binding nerves seen at the fluorescence-microscopic level. A correspondence between granular QC fluorescence and many lysosomal dense bodies is observed both in the cytoplasm of muscle cells and in non-adrenergic, non-cholinergic (NANC) axons during the first few days following injection. A number of brilliantly fluorescent fibres is observed 1 week after injection. At the ultrastructural level, these fibres seem to correlate with NANC axons which are crowded with many dense bodies and large granular vesicles. Notably, some lysosomal dense bodies contain many large granular vesicles. The effects of QC injection on the ultrastructure of adrenergic axons have also been observed, but are not so marked as in the NANC axons. The administration of QC did not cause complete degeneration of the NANC nerves, though degenerating axons were sometimes observed. The present data indicate that most, if not all, QC-binding nerves observed at the fluorescence-microscopic level correspond to NANC nerves at the electron-microscopic level. Furthermore, NANC axons appear to contain a considerable amount of ATP concentrated in the large granular vesicles.
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  • 34
    ISSN: 1432-0878
    Keywords: Satellite cells ; Skeletal muscle ; Snake-venom toxin ; Muscle regeneration ; Electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Satellite cells were studied in the undamaged part of the rat soleus muscle rendered partially necrotic by a subcutaneous injection of notexin, the myotoxic toxin purified from the venom of the Australian snake Notechis scutatus scutatus. Nuclei of satellite cells were twice as numerous as in the controls, with a decreasing gradient in the number of satellite cells with distance from the necrotic area. The cells were in an activated state with an increased cytoplasmic volume and prominent organelles. Occasionally, mitosis of some satellite cells was observed. Between the satellite cell and the muscle fibre, an unusually wide space was frequently seen, within which a “new” basal lamina was often visible. It is suggested that the role of the satellite cells of undamaged muscle fibres in the regeneration of necrotic muscle is worthy of more detailed investigation.
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  • 35
    ISSN: 1615-6102
    Keywords: Digestion ; Membrane flow ; Electron microscopy ; Sarcodina ; Actinophrys sol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The digestion of food in the heliozoonActinophrys sol is characterized by several distinct membrane events. Initially, extrusomes expand and fuse with each other and with the plasma membrane providing the membrane for the nascent food vacuole. During this process a—presumably lytic—material is secreted. After complete forming of the food vacuole a second type of vesicles fuses with it, whereupon usually lysis of the prey occurs. After denaturation and coagulation of the food, fluid is removed from the food vacuole. This process is accompanied by a high cytotic activity around the periphery of the food vacuole. Following this step, the perinuclear Golgi region shows an active appearance and numerous lysosomes fuse with the food vacuole. In consequence of this the food is degradated. The food vacuole shrinks continuously. Simultaneously vesicles filled with the digested material pinch off from the food vacuole, the content of which shows a more and more condensed mass of undigestible material. The undigestible residues are defecated eventually. The process of digestion is accompanied by an increase in volume and number of electron lucent cytoplasmic vacuoles. These vacuoles gradually become filled with a filamentous material starting with the vacuoles in the cell periphery. As the digestion continues, the vacuolar contents become condensed successively. Synchroneously the vacuoles move towards the cell center. After completion of the digestion, the cytoplasmic vacuoles decrease in volume and number and do not show any longer electron dense contents.
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  • 36
    ISSN: 1615-6102
    Keywords: Anacystis nidulans ; Cyanobacterium ; Electron microscopy ; Freeze-fracmres ; Thylakoid degradation ; Ultrathin-sections
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Photooxidative bleaching of the CyanobacteriumAnacystis nidulans was studied by electron microscopic investigation of both freezefractured and thin-sectioned samples. During bleaching four consecutive phases in degradation of photosynthetic membranes (thylakoids) could be characterized: 1. No ultrastructural changes until photosystem II activity is lost. 2. Derangement of characteristic arrangement of thylakoids. 3. Thylakoids visible only in thin-sectioned but not in freeze-fractured samples. 4. Completely bleached cells, only traces in place of former thylakoids visible in thinsectioned samples. Bleaching did not cause lysis of the cells showing that the cytoplasmic membrane was not damaged. Polyhedral bodies also were still detectable in bleached cells.
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  • 37
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    Protoplasma 116 (1983), S. 198-200 
    ISSN: 1615-6102
    Keywords: Chromosome isolation ; Electron microscopy ; Vicia faba ; Vicia narbonensis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Using a formalin fixation technique whole chromosomes from root tips ofVicia species were isolated into a buffer solution. Combining this technique with the use of a set of reciprocal translocations available for this species—Vicia faba— allowed each member of the karyotype to be isolated and identified. Such isolated chromosomes can be used for optical microscopy or for either transmission or scanning electron microscopy where critical point drying clearly reveals chromatin fibre.
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  • 38
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    Protoplasma 116 (1983), S. 209-212 
    ISSN: 1615-6102
    Keywords: Parapharyngeal mass ; Electron microscopy ; Cytochemistry ; Electron microprobe X-ray analysis ; Ciliate ; Homalozoon vermiculare
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The structure and elemental composition of the granules which make up the parapharyngeal mass of the ciliateHomalozoon vermiculare are analyzed. The mass is made up of two kinds of granules. One is not membrane-bounded and is composed of paraglycogen. The second type is comprised of concentric lamellae. It is rich in magnesium, phosphorus, potassium, and calcium. These results do not support the contention that the granules are directly involved in the process of food vacuole formation. The role of the parapharyngeal mass remains obscure.
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  • 39
    ISSN: 1615-6102
    Keywords: Cell walls ; Electron microscopy ; Moisture ; Plastic embedding ; Seeds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Aqueous fixatives caused dry seed tissues to swell; mashed peanuts, crushed to remove oil, swelled even more. Use of anhydrous, organic solvents as vehicles for fixatives enabled maintenance of dimensional stability during fixation of dry seed tissues; even crushed seed tissue did not swell significantly when processed anhydrously. However, anhydrously processed specimens proved difficult to section. The difficulty was due to imperfect permeation of plastic into the seed tissues during embedding. An explanation of why anhydrously processed dry seed tissues are so difficult to embed in plastic is offered.
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  • 40
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    Cell & tissue research 228 (1983), S. 85-98 
    ISSN: 1432-0878
    Keywords: Basement-membrane production ; Mouse embryos ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mouse embryos (strain NMRI) of days 9 + 2h, 9 + 12h, 10 + 2h, 10 + 12h, 11 + 2h, 12 + 2h, 13 + 2h, and 14 + 2h were fixed (i) in 3% glutaraldehyde +3% paraformaldehyde, (ii) in 1% glutaraldehyde +1% tannic acid, or (iii) in 1% glutaraldehyde +1.5% ruthenium red. The electronmicroscopic picture of the basement membrane (BM) changed depending on the fixative used. Addition of tannic acid led to a higher staining intensity of glycoproteins, whereas after ruthenium red proteoglycans were more heavily stained. The BM around the neural tube and around the epithelial tubules in the lung anlage were investigated electron microscopically. After fusion, the BM in the dorsal regions of the neural tube is missing; on days 9–10 it is, however, reformed. Between days 11 and 13 wide gaps in the BM of the lung anlage occur at the growth buds of the epithelial tubes, which are bridged on late day 13. In the basal parts of these two epithelial types membrane-bordered granules of different density occur singly or in groups. It is postulated that these structures contain BM-material and represent secretion granules. After secretion, BM-material is first bound to the cell membrane. This process is important for the initiation of the formation of the BM. Further growth, however, proceeds via lateral aggregation (self-assembly). Thus, intercellular gaps are bridged independent of the cell membrane. The process of lateral aggregation may also explain deviations from the normal course of the BM.
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  • 41
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    Cell & tissue research 233 (1983), S. 209-213 
    ISSN: 1432-0878
    Keywords: Hamsters ; Harderian glands ; Short photoperiod ; Sexual dimorphism ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A sexual dimorphism of the hamster Harderian gland at the ultrastructural level, has been reported. Castration of males and the administration of testosterone to females are known to alter the male type gland to the female type and vice versa. In this paper we present data that exposure to a short photoperiod (1L:23D) can induce similar structural alterations between the 4th and 10th week of exposure. Changes in the male included reduction in the number of tubular clusters and large vacuoles, while in the female the number of membrane formations decreased with an accompanying appearance of tubular clusters.
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  • 42
    ISSN: 1432-0878
    Keywords: Innervation ; Decentralisation ; Hypogastric nerve ; Pharmacology ; Electron microscopy ; Vas deferens ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The physiological, pharmacological and morphological characteristics of guinea-pig vas deferens supplied by hypogastric nerves rendered inactive by decentralisation were compared with those of vas deferens in which the nerve supply had been chronically stimulated for 3–9 days using implanted electrodes. No change was seen in decentralised preparations prior to 7 days, but from 8–15 days, increased sensitivity to application of noradrenaline in vitro was observed, which was shown to be related to reduced transmitter uptake by nerve terminals as well as to an increase in postjunctional sensitivity; there was also increased fatigability 7–14 days following decentralisation. Continuous stimulation of hypogastric nerves at 2 Hz for 4–8 h daily for 4–8 days resulted in enhanced transmitter uptake and reduced responses to noradrenaline; this was associated with a slight increase in noradrenaline content and a faster adrenergic neuromuscular response with a shorter latency. No appreciable changes in nerve or muscle structure studied by electron microscopy were observed following decentralisation, but there was an increase of between 12.5 and 29.6% in the number of close (〈 100 nm) neuromuscular junctions following chronic stimulation for 8 days.
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  • 43
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    Cell & tissue research 228 (1983), S. 433-449 
    ISSN: 1432-0878
    Keywords: Bone marrow (rat) ; Heterophil granulocyte ; Granules ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The development of the heterophil granulocyte in the bone marrow of the rat is described, and an electron-microscopical analysis of the changes in the cytoplasm as well as in the granule population in several stages of maturation is reported. Three types of granule originate in consecutive stages of heterophil maturation. Granules with an internal fine structure (nucleated granules) are the first to be formed, i.e., in early promyelocytes; azurophil granules are formed in late promyelocytes; and specific granules appear in myelocytes. Quantitative analysis showed that the granule population in mature cells, i.e., about 160 granules per electron micrograph, is composed of roughly 14% nucleated granules, 10% azurophil granules, and 76% specific granules. Three cell stages were observed in mitosis: the early promyelocyte, the late promyelocyte, and the myelocyte. Granule counts in non-dividing cells confirmed the occurrence of mitosis in the late promyelocyte and myelocyte.
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  • 44
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    Cell & tissue research 228 (1983), S. 489-496 
    ISSN: 1432-0878
    Keywords: Heart ; Tissue culture ; Electron microscopy ; Myocyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cardiac muscle cells from 3-day-old rat neonates were cultured for periods of 2 to 56 days. In order to facilitate ultrastructural studies on the organization of the sarcoplasmic reticulum, the cells were prepared for transmission electron microscopy according to a regimen including postfixation in reduced osmium ferrocyanide. The nonjunctional sarcoplasmic reticulum (NJSR) was organized as a loose, fenestrated sleeve around the exterior of bundles of myofilaments and was particularly prominent at the level of the Z line. The only recognizable junctional elements of the sarcoplasmic reticulum were in a peripheral location. Reduced osmium ferrocyanide was also useful in distinguishing intermediate (10nm) filaments, since it understained Z substance, which often obscured these structures. Intermediate filaments were arranged both at the Z line and the intercalated disc, in parallel strands, approximately at right angles to the myofilaments.
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  • 45
    ISSN: 1432-0878
    Keywords: CRF ; immunolabelling ; Paraventricular nucleus ; Median eminence ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The corticotropin releasing factor (CRF)-synthesizing perikarya and neural processes were detected at ultrastructural level in the hypothalamic paraventricular nucleus and in the median eminence of control and colchicine-pretreated rats. The unlabelled antibody peroxidase-antiperoxidase complex (PAP) immunohistochemical method was used in a pre-embedding manner, on thick, non-frozen sections. In CRF-perikarya, neurosecretory granules (80–120 nm in diameter), free ribosomes, and the rough endoplasmic reticulum were labelled. Unlabelled axon terminals formed asymmetric synapses on CRF-containing perikarya and dendrites. Immunolabelled axons terminated in the palisadic zone of the median eminence.
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  • 46
    ISSN: 1432-0878
    Keywords: Smooth muscle ; Anura ; Stomach ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The young of the aquatic Australian frog, Rheobatrachus silus (Leptodactylidae) develop from eggs to juvenile frogs in the mother's stomach. During brooding the stomach expands greatly and becomes very thin walled. Transmission electron microscopy showed that the distension of the stomach was accompanied by a severe disruption of the smooth muscle layers. Many of the smooth muscle cells seemed to be highly contracted and resembled smooth muscle cells contracted in the absence of an intact connective tissue matrix. Eight days after the birth of the juveniles through the mouth of the female, the stomach muscle cells had returned to a normal appearance. It is suggested that during gastric incubation of the young, smooth muscle cells become at least partially dissociated from their surrounding connective tissue matrix, allowing maximal distension of the stomach wall.
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  • 47
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    Cell & tissue research 234 (1983), S. 579-593 
    ISSN: 1432-0878
    Keywords: Rods ; Cones ; Retina ; Bullfrog ; Synapse ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Lumps of electron-dense material were observed in synaptic clefts associated with all types of photoreceptors, in the vicinity of the synaptic ribbons, in the retinae of dark-adapted frogs. Frogs were reared under a cyclic illumination (light on at 8:00; light off at 20:00) and then exposed to one of two courses of dark adaptation: one started from 11:00 in the morning, and the other started from 20:00 in the evening. The synaptic clefts of red rods became wider at some places where spherical or polygonal lumps of dense material were accumulated. The frequency and sectional area of the lumps increased faster for the first hour in the regime starting from 20:00 than in the regime starting from 11:00, then they reached the similar saturation levels of about 0.6 (per ribbon) and 1.6 to 1.8×104 (nm2) in both the regimes. In greenrod synapses, plate-shaped lumps of dense material were present in synaptic clefts and interspaces between the processes of second-order neurons. In cone synapses at the end of about 1 h darkness, the frequency and area of the lumps reached maximum values of about 0.12 (per ribbon) and 9×103 (nm2) in the regime starting from 11:00 and, about 0.08 (per ribbon) and 4 × 103 (nm2) in the regime starting from 20:00. On exposure to light, the dense material abruptly disappeared from all types of photoreceptor synaptic clefts. Large dense-core vesicles, occasionally observed in light-adapted rod photoreceptor terminals, seem to participate in exocytosis of the dense material. The number of dense-core vesicles per synaptic ribbon in a terminal was about 0.55 at the end of 3 h light in the morning and about 1.28 at the end of 12 h light in the evening. The increased number of dense-core vesicles during the daytime may contribute to the faster accumulation of dense material in the synaptic clefts. Although the chemical identification or the functional significance of the electron-dense material remains unknown, it is interesting that this material showed a rise and fall in response to darkness and illumination. Also the fact that this material is clearly visible will be helpful for future analysis of frog photoreceptor synapses.
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  • 48
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    Cell & tissue research 232 (1983), S. 593-600 
    ISSN: 1432-0878
    Keywords: Peritrophic membrane ; Insect ; Microvilli ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A double plasma membrane (DPM) surrounding intestinal microvilli of the migratory milkweed bug, Oncopeltus fasciatus, is described. Mutant and wild types of the phytophagous insect have been studied by conventional SEM and TEM procedures with the use of membrane-enhancing staining methods. Longitudinal and transverse sections revealed a DPM surrounding microvilli and continuing over the apical portions of the intestinal cell. The outer membrane of the DPM contributes to an intestinal lining or peritrophic membrane (PTM), which apparently accumulates in layers. SEM studies reveal a rugose intestinal surface and complete PTM in both starved and fed insects. Only rarely are exposed microvilli seen by SEM. SEM examinations also enable the observation of numerous blebs on the luminal side of the PTM apparently held in position by a neck-like attachment and apparently derived from the outer membrane of the DPM. Preliminary TEM studies of microvilli revealed unique microvesicle-like structures, lying just inside the inner membrane of the DPM, which may be of membrane origin based on their typical trilaminar appearance after en bloc staining with uranyl acetate. Highly ordered microfilaments were observed to occupy the most central aspect of the microvilli.
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  • 49
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    Cell & tissue research 234 (1983), S. 125-134 
    ISSN: 1432-0878
    Keywords: Vasopressin ; Immunocytochemistry ; Electron microscopy ; Hypothalamus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Vasopressin-containing neurons, identified by immunocytochemistry, are located predominantly in the posterior magnocellular division of the paraventricular nucleus of the rat hypothalamus. By electron microscopy, the immunoreaction product is seen within the cell bodies and neuronal processes. In the perikarya and dendritic processes, the immunoreactive material is associated primarily with neurosecretory granules. Axonal processes, identified by their content of microtubules and accumulation of neurosecretory granules, show the immunoreaction product in association with both of these organelles. Afferent axo-dendritic, axo-somatic and putative axo-axonic synapses with immunostained vasopressinergic neurons can be identified. The presynaptic profiles do not contain immunoreactive material. This study contributes to the ultrastructural characterization of vasopressinergic neurons in the paraventricular nucleus and of their afferent synaptic input.
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  • 50
    ISSN: 1432-0878
    Keywords: Bone marrow (mouse) ; Monocytes ; Neutrophil granulocytes ; Granules ; Electron microscopy ; Peroxidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The differentiation and maturation of monocytes and neutrophil granulocytes were studied in bone marrow of normal mice by electron microscopy and cytochemical assessment of peroxidatic activity. The granule populations of the mature cells of bone marrow were identified and investigated to obtain a basis for the analysis of the earlier stages of maturation. Mature monocytes and neutrophils showed primary and secondary granules, and mature neutrophils had more of both kinds. The size, shape, and number of primary granules proved to offer the most reliable criteria for distinguishing promonocytes and promyelocytes. The primary granules of monocytes were smaller than those of mature neutrophils and were either spherical (smallest diameter 50–200 nm) or elongate (100×400 nm). Both granules had a homogeneous matrix. The granules of the granulocytes were either spherical (smallest diameter 200–300 nm) or elongate (150–200×300–500 nm), and some of them had a crystalline inclusion.
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  • 51
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    Cell & tissue research 228 (1983), S. 139-148 
    ISSN: 1432-0878
    Keywords: Pineal organ ; Pineal photoreceptors ; Opsin immunoreactivity ; Electron microscopy ; Elasmobranch (Raja clavata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pineal organ of Raja clavata was studied by light and electron microscopy, including the immunocytochemical antiopsin reaction. The pineal organ of the ray consists of three portions: (i) a large proximal pineal, (ii) a long tube-like connecting stalk, and (iii) a short distal terminal enlargement. This latter end-vesicle lies in the deep connective tissue layers of the braincase. All portions of the pineal are composed of pinealocytes, intrinsic neurons, ependymal/glial cells, and bundles of nerve fibers embedded in thin neuropil formations. The inner segments of the pinealocytes protrude into the lumen in all parts of the organ and usually contain basal bodies and numerous mitochondria. Often, two outer segments were found to arise from the basal bodies of a single inner segment. By means of light-microscopic immunocytochemistry the outer segments showed a strong antiopsin reaction. The axons of the pinealocytes form ribbon-containing synapses on dendritelike profiles, which appear to belong to the intrinsic pineal neurons. There are other axo-dendritic synapses established by presynaptic terminals lacking ribbons and containing granular and synaptic vesicles. Pineal neurons may contain granular vesicles approximately 60–100 nm in diameter; their processes contribute to the bundles of unmyelinated axons. The fine structural organization of the pineal organ and the opsin immunoreactivity of the outer segments of the pinealocytes indicate a photoreceptive capacity of the organ. The double outer segments represent a peculiar multiplication of the photoreceptor structures.
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  • 52
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    Cell & tissue research 231 (1983), S. 551-563 
    ISSN: 1432-0878
    Keywords: Visual mutants ; Anterior optic tract ; Independent gene actions ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopy shows that in wild-type Drosophila melanogaster the anterior optic tract (AOT) is formed by about 1260 fibers in males and slightly fewer in females. Golgi staining suggests that most AOT fibers connect the lobula with different regions of the central brain. In the sine oculis (so) and small optic lobes (sol) mutants the number of axons is drastically reduced, by 58% in sol and by 35% in so. In the double mutant sol:so there is a loss of up to 83% of the fibers in the AOT. Approximately half of the remaining 220 fibers form a well defined subbundle of very thin axons which is identifiable in wild type as well as in both single mutants. The fibers of this subbundle neither originate nor terminate in the visual ganglia: instead, they connect two different central brain regions. It is concluded that the combined action of the sol and so mutations abolishes more than 90% of the fibers of visual origin or destination in the AOT. Quantitative analysis of electron micrographs shows that the so and sol mutations act independently on nearly exclusive subsets of axons in the AOT.
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  • 53
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    Cell & tissue research 234 (1983), S. 469-496 
    ISSN: 1432-0878
    Keywords: Bone marrow (human) ; Neutrophil granulocyte ; Granules ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Bone marrow from hematologically healthy adults was exposed to a number of fixation procedures for investigation of the heterogeneity of the granule population in neutrophil granulocytes at the ultrastructural level. Four main cell stages were distinguished: early promyelocyte, late promyelocyte, myelocyte, and mature neutrophil granulocyte and described separately; metamyelocytes and band-form or stab cells are described together. The characteristic changes in the cytoplasm during myelopoiesis were analysed quantitatively. Special attention was given to the development of the granule population. Three types of granule arise in successive cell stages: granules which develop a sub-structure in the matrix (nucleated granules) are formed in early promyelocytes, granules with a homogeneous electron-dense matrix (azurophil granules) in late promyelocytes, and granules with a less electron-dense matrix (specific granules) in myelocytes. The three types of granule remain present during myelopoiesis. The best results in distinguishing the granule types were obtained by prefixation either in 0.1% glutaraldehyde or in 1.5% glutaraldehyde followed by washing in phosphate-buffered Ringer solution to which aminotriazole had been added. Granule counts revealed for the mature neutrophil a total number of granules of about 220 per ultrathin section. This population of granules is composed of about 12% nucleated, 11% azurophil, and 77% specific granules. When our previous findings are taken into account, the existence of three successively formed and morphologically distinguishable types of granule in heterophil (neutrophil) granulocytes has been demonstrated for three mammalian species: the guinea pig, the rat, and man. A separate term for the early promyelocyte stage is proposed: eomyelocyte.
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  • 54
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    Cell & tissue research 232 (1983), S. 379-397 
    ISSN: 1432-0878
    Keywords: Electron microscopy ; Pelvic ganglia ; Autonomic nervous system ; Synapses ; Neurones ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A semi-quantitative electron-microscopic study of neuronal cell bodies, nerve profiles and synapses in the anterior pelvic ganglia of the guinea-pig has been carried out following in vivo labelling of adrenergic nerve endings with 5-hydroxydopamine. Ganglion cells of three main types have been distinguished: 1) the majority (about 70%) not containing granular vesicles, probably cholinergic elements; 2) those containing large granular vesicles of uniform size (80–110 nm), with granules of medium density and prominent halos; and 3) those containing vesicles of variable size (60–150 nm), with very dense eccentrically placed granular cores. Some non-neuronal ‘granule-containing’ cells were present, mainly near small blood vessels. Some 95% of the total axon profiles within the ganglia were cholinergic, the remaining 5% were adrenergic. However, 99% of synapses (i.e. axons within 50 nm of nerve cell membrane with pre-and post-synaptic specialisations) were cholinergic, and 1 % were adrenergic. Only three examples of nerve cell bodies exhibiting both cholinergic and adrenergic synapses were observed. Unlike the para-and prevertebral ganglia, the pelvic ganglia contained large numbers of axo-somatic synapses. As many as 20% of the nucleated neuronal cell profiles displayed two distinct nuclei.
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  • 55
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    Cell & tissue research 232 (1983), S. 399-411 
    ISSN: 1432-0878
    Keywords: Pelvic ganglion ; Reinnervation ; Decentralisation ; Autonomie nervous system ; Electron microscopy ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An electron-microscopic study has been made of adrenergic and cholinergic nerve fibres and synapses in the pelvic ganglion of the guinea-pig at intervals of up to 60 days following section of the hypogastric and pelvic nerves. Transection of the hypogastric nerves led to degeneration of 80–90% of the cholinergic nerve profiles and synapses in the ganglion. The small number of adrenergic nerves and synapses did not change, but 30–60 days after section, this number increased 8–10 times. Transection of the pelvic nerves led to degeneration of about 15% of the cholinergic nerve terminals, but no change in adrenergic terminals. After transection of both hypogastric and pelvic nerves, only about 1% of cholinergic nerves survived, but after 30–60 days, the number of adrenergic nerves increased 8–10 times. It is concluded that following cholinergic nerve degeneration in the ganglion, adrenergic nerves, probably originating as collateral sprouts from postganglionic neurones and granule-containing cells, can replace them to some extent.
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  • 56
    ISSN: 1432-0878
    Keywords: Dictyosome-like structures ; Golgi apparatus ; Phosphatidylcholine ; Laminated figures ; Electron microscopy ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Dictyosome-like structures (DLS) of guinea pig spermatocytes, when prefixed in mixtures of glutaraldehyde and tannic acid, exhibited laminated figures with a repeating periodicity of about 4.5 nm in the spaces between DLS saccules or in association with the surfaces of the DLS saccules. These laminated figures were similar to those figures derived from saturated lipids in other tissues. Alternatively, spaces between saccules were collapsed leaving only thin, electron-dense material separating adjacent saccules. These changes were not observed when the DLS were prefixed in glutaraldehyde before exposure to tannic acid. The presence of laminated figures following fixation with tannic acid and osmium tetroxide suggests that saturated lipids are present in, or associated with, the intersaccular regions of the DLS. The distribution of laminated figures in other membrane structures was not affected by post fixation with tannic acid nor were laminated figures comparable to those of the DLS observed between cisternae of the Golgi apparatus. These results support previous conclusions that DLS are distinct from Golgi apparatus and are a unique component of the germ cell cytoplasm.
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  • 57
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    Angewandte Chemie International Edition in English 22 (1983), S. 456-485 
    ISSN: 0570-0833
    Keywords: Electron diffraction ; Transmission electron microscopy ; Electron microscopy ; Structure elucidation ; Ribosomes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chemists recognize X-ray crystal structure analysis and electron microscopy as powerful methods of analysis. In the last 20 years the basic ideas of X-ray diffraction analysis have been extended to the field of electron microscopy, whereby an image-forming apparatus is converted into an electron diffractometer, and through which an old dream of crystallographers can be realized - the measurement of the phase shift of scattered waves, a prerequisite for the direct calculation of structures. Its most important area of application, like that of the X-ray diffractometer, is in three-dimensional structure analysis - in all fields of science. However, beyond crystallography, aperiodic structures (comparable to crystals with a single unit cell) can also be analyzed three-dimensionally. In this progress report, the development of the first idea (spatial frequency filtering) to the analysis of ribosomal particles is outlined. Attention will be focused primarily on quantitative methods for the measurement of scattered rays, which are also usable beyond the conventional limit of resolution, down to atomic resolution. In the course of this work in 1968, the principle of the three-dimensional analysis of native biological crystal structures using the electron microscope, as worked with today in many laboratories, was developed. In Munich, however, further research focused on the three-dimensional analysis of aperiodic and individual (especially biological) objects. The analysis of 50S-subunits of the procaryotic ribosome of E. coli showed surprisingly good reproducibility of the results (although only within the same orientation), allowing the deduction of almost ideal average model structures from a limited number of particles.
    Additional Material: 28 Ill.
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  • 58
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    Virchows Archiv 377 (1978), S. 129-144 
    ISSN: 1432-2307
    Keywords: Nephropathia epidemica ; Hemorrhagic fever ; Glomerular changes ; Immune complex disease ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electron microscopical changes in the glomeruli in 20 kidney biopsies from 18 patients, who were suffering from or had lately suffered from Nephropathia epidemica were studied. Various kinds of deposits were seen. Under the endothelial cells there were collections of light flocculent material. Small dark deposits were seen in the mesangium at the mesangial cell processes, inside the thickened basement membrane, and occasionally on the epithelial side of the membrane. Large deposits were seen around mesangial cells in the mesangium. Deposits were less numerous than in chronic immune complex diseases. The intramembranous or subepithelial deposits were associated with “moon craters”, membranous convoluted structures or membrane debris. Granular extracellular mesangial material, round extracellular particles and intraendothelial microtubular inclusions were occasionally seen. In two of our cases occasional capsular epithelial cells showed numerous myelin bodies. Typical viruses were not seen in the glomeruli. The findings are in accord with the short period of scanty immune complex deposition in the glomeruli in the clinically active phase of Nephropathia epidemica.
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  • 59
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    Virchows Archiv 378 (1978), S. 55-65 
    ISSN: 1432-2307
    Keywords: Pituitary adenoma ; Acromegaly ; Hormone secretion ; Electron microscopy ; Immunologic techniques
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ultrastructural examination of 184 pituitary adenomas demonstrated the presence of extracellular accumulations of electron dense material in 3 out of 64 cases with acromegaly. Fibrillary structures were seen in larger deposits of such material. This material was only observed in biopsies fixed directly with osmium tetroxide; initial fixation with glutaraldehyde did not retain the material and left empty spaces. Positive immuno-histochemical reaction with specific antibodies demonstrated that the extracellular material contained growth hormone (GH). The presence of this extracellular material could not be related to the age or sex of the patient nor to the duration of symptoms, size of the tumor, presence of diabetes mellitus, or concomitant secretion of prolactin. The pericapillary fibrous sheath was heavily thickened in the patient with the longest duration of symptoms, intermediate in thickness in the second and normal in the third.
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  • 60
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    Virchows Archiv 379 (1978), S. 73-83 
    ISSN: 1432-2307
    Keywords: Neurofibrome ; Tactile-like corpuscles ; Perineurial cell ; Neuroectodermal origin ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In neurofibromas type I (plexiform) and type II (diffuse) the Schwann cell is the predominant cell in the neoplastic proliferation. Electron microscopic investigation of a neurofibroma with structures resembling tactile corpuscles (type III) revealed neoplastic proliferation of perineurial instead of Schwann cells. The tactile-like (pseudo-Meissnerian) corpuscles (corpuscules neurofibromateux) are formed by neoplastic perineurial cells. These cells have a tendency to wrap themselves around longitudinal structures, such as collagen fibres or axons, and to come into direct contact with the latter. This close relationship between the axon and the neoplastic perineurial cell, analogous to that between axon and Schwann cell, points to a neuroectodermal origin of the perineurial cell. The electron microscopic appearances suggest that either the Schwann cell or the perineurial cell is the essential neoplastic component of neurofibromas, the fibroblastic proliferation being a secondary phenomenon.
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  • 61
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    Virchows Archiv 381 (1978), S. 1-11 
    ISSN: 1432-2307
    Keywords: Central neuroblastoma ; Electron microscopy ; Growth cone ; Primitive neural crest ; Neuronal cytogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A cerebral neuroblastoma removed surgically from a female child is presented. Electron microscopy showed numerous neuronal processes with growth cones which are a feature of the developing neurone. In addition there were some rosettes with distinct lumina. The luminal surfaces were covered with a smooth plasma membrane lacking any surface differentiation and the lateral surface of these cells had many cell junctions (terminal bars), reminiscent of a primitive neural tube. These features in a nerve cell tumor help to substantiate it as a neuroblastoma arising from immature rather than differentiated cells. The nature of this rare tumor is discussed.
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  • 62
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    Virchows Archiv 378 (1978), S. 75-90 
    ISSN: 1432-2307
    Keywords: Morbus Fabry ; Electron microscopy ; Freeze-fracturing ; Heterozygotic women ; Homozygotic men
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es werden elektronenmikroskopische Beobachtungen zur Lokalisation und zur Feinstruktur der Glykolipideinschlüsse in verschiedenen inneren Organen bei Morbus Fabry berichtet. Die intrazellulÄren und extrazellulÄren Einschlüsse bestehen aus vielschichtig lamellÄren Membransystemen in konzentrischer und exzentrischer sowie in stapeiförmiger paralleler Anordnung. Diese lamellÄre Anordnung ist charakteristisch für flüssigkristalline Phasen von Phospholipid-Wasser-Systemen. Erstmalig werden ultrastrukturelle Befunde an den inneren Organen einer erkrankten Frau mitgeteilt. Demzufolge lassen sich bei heterozygoten Frauen gleiche Glykolipidablagerungen wie bei homozygoten MÄnnern nachweisen. Die Beziehung der Glykolipideinschlüsse zu den Lysosomen wird erörtert.
    Notes: Summary Electron microscopic findings are reported on the localization and fine structure of glycolipid inclusions in different organs (heart, kidney, lymph nodes, arterial blood vessels, pancreas) in Fabry's disease in a female. The intracellular and extracellular inclusions were made up of multilamellar membraneous systems in concentric, excentric, and parallel arrangement. This fine structure is characteristic of liquid-crystalline phases of phospholipid-water systems. The same type of inclusions are found in the internal organs of heterozygotic women as in homozygotic men. The relationship between the glycolipid inclusions and the lysosomes is discussed.
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  • 63
    ISSN: 1432-2307
    Keywords: Megacolon ; Large intestine ; Endocrine cells ; Immunohistochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The large intestine resected from 6 Hirschsprung's patients and surgical colonic biopsies from 6 control children were examined with light and electron microscopy. The presence and the relative distribution of various endocrine cell types in both groups of mucosa were determined. In light microscope studies endocrine cell data were expressed as number of cells per unit area of mucosa using a quantitative method after argentaffin and Grimelius's argyrophilic techniques and an immunoperoxidase reaction with glucagon and somatostatin (SRIF) antisera. The results indicate that endocrine cells are apparently not involved in Hirschsprung's disease, since their number and frequency did not differ significantly between the ganglionic and aganglionic segments of Hirschsprung's patients nor between the latter and control children. Glucagon immunoreactive cells were, on the average, 5–6 times and 7–9 times more numerous that SRIF cells in the rectum and the sigmoid, respectively. Ultrastructurally, five endocrine cell types could be distinguished. The fifth type, probably a transition type, apparently disappears in adults.
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  • 64
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    Virchows Archiv 380 (1978), S. 31-48 
    ISSN: 1432-2307
    Keywords: Human liver ; Acute alcoholic hepatitis ; Histoenzymology ; Electron microscopy ; Alcoholic cirrhosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The interpretation of the morphological features of alcoholic hepatitis is discussed in terms of a comparison with the results of an ultrastructural and histoenzymological study of the liver biopsies of nine patients. In these patients liver biopsies were performed in the initial stage of the illness and fifteen days after five were re-biopsied, when the clinical and biological signs were improved. The correlations between morphological and biological data were good, especially for the levels of serological and histoenzymological alkaline phosphatase and gamma-glutamyltranspeptidase evaluations. However, when histological appearances had returned to normal, after two weeks of abstinence from alcohol several histological and ultrastructural features of the initial hepatitis persisted. The presence of evolving cirrhosis was a contributing factor to the severity of the changes seen. Morphologically, apart from the changes due to chronic alcoholic intoxication (steatosis, mitochondrial alteration), the hepatitic lesions comprise Mallory's bodies, cytoplasmic oedema and mitochondrial swelling. Cholestasis was invariably present. Histo-enzymologically there was a reduction in ATPase activity suggesting a metabolic failure in the energy producing pathways. In addition, in the periphery of lobules an active cirrhotic process was present, with tubular de-differentiation of hepatocytes and an increase in gamma-glutamyltranspeptidase on the cytoplasmic membrane. Because of the absence of any topographical relationship between hepatitis and cirrhosis, the presence of lymphocytes in the neighbourhood of the ductules suggested an indirect relationship between both processes, perhaps an autoimmune response initiated by Mallory's bodies.
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  • 65
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    Virchows Archiv 380 (1978), S. 317-325 
    ISSN: 1432-2307
    Keywords: Meningioma ; Psammoma bodies ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Psammoma bodies from eight meningiomas have been examined by both light and scanning electron microscopy (SEM). The bodies are primarily composed of calcium apatite which is deposited within a nidus of tightly laminated collagen fibers.
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  • 66
    ISSN: 1432-2307
    Keywords: Limb bud cultures (mouse) ; Electron microscopy ; Effect of highly sulfated GAG (SP54® and Arteparon®) ; Collagen structure ; Cartilage pattern
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Addition of 1 mg/ml or higher doses of the highly sulfated pentosanpolysulfoester SP54® or the mucopolysaccharidepolysulfoester Arteparon® to limb bud cultures from 11-day-old mouse embryos caused a marked reduction in the growth of the distal parts of the cartilage anlagen. The most striking effect, however, was the change in the collagen structure of the cartilaginous intercellular substance. After more than 0.05 mg/ml SP54® or Arteparon® no collagen filaments were seen but collagen aggregates with an altered cross-striation occurred. They were produced by an antiparallel arrangement of collagen molecules caused by the highly sulfated substances. By immunofluorescence microscopy it was shown that SP54® and Arteparon® did not influence the distribution of the collagen types but only affected the aggregation of collagen type II. From the morphological point of view the production of endogenous PG seemed to be uneffected by SP54® and Arteparon®. The effect of SP54® and Arteparon® was reversible. After removal of these substances characteristic collagen filaments re-formed. The collagen aggregates were decomposed extracellularly or phagocytosed by chondroblasts and decomposed intracellularly.
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  • 67
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    Virchows Archiv 378 (1978), S. 181-197 
    ISSN: 1432-2307
    Keywords: Axonal swelling ; Spheroid ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Axonal swellings and spheroids in various human diseases were studied by light and electron microscopy. 4 cases of infantile neuroaxonal dystrophy, 2 of degenerative diseases, 2 brain tumors and 3 of cerebrovascular disease were examined. Ultrastructurally most spheroids in infantile neuroaxonal dystrophy consisted of interconnected tubules, stacked membranotubular profiles, alternating layered membranes and accumulations of neurofilaments. Combinations of these four constituents were seen only in infantile neuroaxonal dystrophy. “Torpedos” (fusiform swelling of the axon of a Purkinje cell) consisted exclusively of neurofilaments. Spheroids in case 6 (mental retardation) and 7 (atypical teratoma) consisted of interwoven skeins of neurofilaments and grouped mitochondria. Spheroids in case 8 (demyelination) and 9 (cerebrovascular disease) consisted of packed complex bodies and mitochondria. Spheroids in cases 10 and 11 (cerebrovascular disease) consisted of degenerating organelles only. The morphological differences between cases 9, 10 and 11 probably depends on the severity and timing of the cerebral injury. Most spheroids show similar histological and histochemical properties, but ultrastructural study may give some clue to the origin of the bodies.
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  • 68
    ISSN: 1432-2307
    Keywords: Human parathyroid adenomas ; Electron microscopy ; Parathyroid hormone release ; PTH radioimmunoassay ; Pathophysiology of primary hyperparathyroidism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Twelve parathyroid chief cell adenomas from patients with primary hyperparathyroidism were incubated in a tissue culture system in the presence of different calcium concentrations and for various time periods. The endocrine response of the tissue was examined electron microscopically and radioimmunologically. After incubation in a medium of low calcium concentration the parathyroid adenomas showed ultrastructural signs of stimulation with proliferation of the hormone-synthesizing organelles. The development of the ultrastructural response could first be observed after four hours and increased up to several days. Radioimmunologically, an increase of the hormone secretion could be demonstrated. Converse results were obtained after incubation of the tumor tissue under suppressive culture conditions. To check for de-novo synthesis of the hormone released the tissue was incubated in a 75Se-methionine-containing medium. This resulted in radioactivity of the secreted parathyroid hormone, indicating de novo synthesis in our culture system. The biological potency of the released hormone was demonstrated by comparison of the PTH out of the medium with the international human MRC standard using two different radioassays.
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  • 69
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    Virchows Archiv 378 (1978), S. 347-359 
    ISSN: 1432-2307
    Keywords: Hyaline cartilage ; Proteoglycans ; Glycogen ; Matrix degeneration ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Hyaline cartilage of the talus of a diastrophic dwarf was studied by light and transmission electron microscopy before and after proteoglycan extraction or digestion, glycogen digestion, and enzyme marking. The nuclei of the chondrocytes were as a rule large and round and the cytoplasm contained large vacuoles. Best's carmine stained the cytoplasm of most cells red; after diastase digestion the cytoplasm remained unstained. This suggested that the cells contained glycogen. This observation was complimented by the ultrastructural demonstration of large amounts of glycogen. Cell scars were frequent. The shape and state of activity of the cells as well as the development of intracytoplasmic organelles showed great variability. The matrix showed many areas of degeneration and a general dearth of sulphated acid mucopolysaccharides. A lacey pattern of unmasked collagen fibers was frequently seen. Collagen fibers showed a great variability in diameter and often appeared frayed when examined by electron microscopy. These observations suggest an enzymatic deficiency in chondrocyte mucopolysaccharide and glucose metabolism. The techniques we used when added to biochemical studies should prove useful in the investigation of human dwarfism.
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  • 70
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    Virchows Archiv 379 (1978), S. 25-33 
    ISSN: 1432-2307
    Keywords: Electron microscopy ; Microfilaments ; Microtubules ; Nuclear pockets ; Smooth muscle tumours
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Samples of gastric leiomyosarcomas from two male patients (69 years and 57 years of age) were studied by electron microscopy. The tumour cells contained abundant 50–90 å thick microfilaments and microtubules. Another cell type, regarded as immature leiomyosarcoma cell, contained numerous profiles of granular endoplasmic reticulum, free ribosomes and a well developed Golgi apparatus. There were intercellular junctions of zonula adherens-type between adjacent tumour cells. It was concluded that electron microscopy offers a valuable aid in the diagnosis of gastric neoplasms of smooth muscle origin.
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  • 71
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    Virchows Archiv 379 (1978), S. 85-97 
    ISSN: 1432-2307
    Keywords: Bronchial carcinoid ; Oncocytoma ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We describe a bronchial tumor with a biphasic pattern. The main cellular population is composed of large cells with eosinophilic cytoplasm packed with mitochondria. These oncocytes countain few dense-core membrane limited granules. The secondary cell population has the morphological and histochemical features that characterize the typical bronchial carcinoid. A third cell type, recognizable at ultrastructural level, contains numerous neurosecretory granules and abundant large mitochondria, seeming therefore to represent a transitional cell form. We assume that oncocytes and carcinoid cells, found in the same tumor with intermediate forms, represent the extremes of a morphological spectrum. Furthermore, the oncocytic cytoplasmic components (neurosecretory granules and the mitochondria) are present in reciprocal arrangement in the carcinoid cells. These observations, together with similar reported cases suggest that the oncocytic state corresponds to a functional stage. We consider that oncocytes from this endobronchial tumor and from similar pathologic conditions reported in the literature correspond to carcinoid cells with mitochondrial hyperplasia and with diminished endocrine activity. This oncocytic carcinoid tumor is associated, in the same pulmonary lobe, with a second neoplasm that has the histological and ultrastructural features of a poorly differentiated carcinoid (oat-cell carcinoma).
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  • 72
    ISSN: 1432-2307
    Keywords: Human myocardium ; Left ventricle ; Electron microscopy ; Morphometry ; Aging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Licht- und elektronenmikroskopisch wurde mit einem manuell-optischen Bildanalysesystem eine morphometrische Analyse am Herzmuskel durchgeführt. Das Untersuchungsgut stammte aus nicht belasteten menschlichen linken Ventrikeln, welches bei herzchirurgischen Eingriffen gewonnen wurde. Bei den Patienten lag entweder ein Foramen ovale persistens, ein Vorhofseptumdefekt (ASD) I.–II. Grades oder eine reine Mitralstenose III.–IV. Grades vor. Die linken Kammerdruckmittelwerte lagen im Normbereich. Das Patientengut konnte in eine junge Patientengruppe von 5–15 Jahren und in eine alte Patientengruppe von 42–78 Jahren unterteilt werden. Lichtmikroskopisch wurde ermittelt, da\ sich der Anteil des Interstitium am Herzmuskelgewebe mit dem Alter nicht verÄndert. Die Anzahldichte der Herzmuskelzellkerne nimmt im Alter ab (P〈0,001), was auf eine Verringerung der Anzahldichte der Herzmuskelzellen pro Testvolumen und eine Vergrö\erung der einzelnen Herzmuskelzelle schlie\en lÄ\t. Elektronenmikroskopisch konnte eine Vermehrung der Volumendichte der Myofibrillen (P〈0,02) mit zunehmendem Alter nachgewiesen werden, wÄhrend die Volumendichte der Mitochondrien konstant bleibt und die Volumendichte des restlichen Cytoplasmas sogar abnimmt (P〈0,05). Die Anzahl der Mitochondrien erhöht sich im Alter (P〈0,001), so da\ bei den einzelnen Mitochondrien mit zunehmendem Alter eine Verkleinerung eintritt.
    Notes: Summary An ultrastructural and morphometric analysis was performed on human myocardial left ventricle, obtained during surgical heart operations on normally loaded ventricles. The diagnoses of the patients were a) Persistant foramen ovale b) Atrial septal defect stage (I.–II.) c) Mitral stenosis (stage III.–IV.). The median values of left ventricular pressure were not pathologically elevated. The patients were divided in 2 groups, the younger one ranging from 5–15 years, the older from 42–78 years. It was shown that the volume density of the interstitial tissue does not differ with the aging process. The number of the nuclei per test area of the heart muscle cells decreased within age (P〈0.001). This finding suggests a decreasing process in the number of the heart muscle cells and an increase in size of the individual myocardial cell. Increase in the volume density of myofibrils was demonstrated at electron microscopical level with aging (P〈0.02). The volume density of mitochondria is the same in both groups, whereas the volume density of the remaining cytoplasm (without myofibrils and mitochondria) decreases (P〈0.05). The numerical density of the mitochondria increased in the older patient group (P〈0.001).
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  • 73
    ISSN: 1432-2307
    Keywords: Human myocardium ; Left ventricle ; Hypertrophy ; Electron microscopy ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An den KammerwÄnden menschlicher linker Ventrikel, die auf Grund einer Aortenstenose, einer Aorteninsuffizienz oder eines kombinierten Aortenvitium hypertrophiert waren, wurden licht- und elektronenmikroskopisch morphometrische Untersuchungen angestellt. Die Ergebnisse wurden mit denen, die an nicht belasteten menschlichen linken Ventrikeln gewonnen wurden, verglichen. Lichtmikroskopisch unterscheiden sich die Anteile der Volumendichten des Interstitium und der Herzmuskelzellen am gesamten Herzmuskelgewebe nicht statistisch signifikant. Es konnte morphometrisch eine Zellvergrö\erung festgestellt werden, die aus der signifikanten Verringerung der Volumendichte der Zellkerne (P〈0,001) und der Anzahl der Zellkerne pro TestflÄche (P〈0,0001) gegenüber den beiden Normalkollektiven resultiert. Elektronenmikroskopisch ist eine Zunahme der Volumendichten der Myofibrillen (P〈0,0001) auf Kosten des restlichen Cytoplasmas (P〈0,001) festzustellen, wÄhrend die Volumendichte der Mitochondrien im Vergleich mit den jungen und alten Patienten abnahm (P〈0,0001). Die OberflÄchendichte der Mitochondrien verringerte sich gegenüber den beiden Vergleichskollektiven (P〈0,001) ebenso wie die der Cristae mitochondriales (P〈0,0001). Diese Ergebnisse finden ihr morphologisches Korrelat in Mitochondriendestruktionen. Eine vermehrte Myolyse hat bei den hypertrophierten Herzen, die alle gewichtsmÄ\ig über dem kritischen Herzgewicht lagen, noch nicht eingesetzt. Bei allen Patienten wurde der herzchirurgische Eingriff mit Erfolg durchgeführt.
    Notes: Summary Biopsies of hypertrophied human myocardial left ventricles were investigated morphometrically. The diagnoses of the patients were stenosis of the aortic valve, aortic insufficiency or a combination of both lesions. The results were compared with those from normally loaded human left ventricles. There are no differences on light microscopical level between the volume densities of interstitial tissue and of heart muscle cells in the three groups of patients. A significant diminution of the volume density of the nuclei (P〈0.001) and the number of nuclei per test area (P〈0.0001) when compared with normal groups suggests an increase in volume of the single heart muscle cell. The ultrastructural study shows marked increase in volume density of myofibrils (P〈0.0001), with accompanying decrease in the volume densities of mitochondria (P〈0.0001) and the remaining cytoplasm (P〈0.001). A gross decrease in the surface area of mitochondria (P〈0.001) and of cristae mitochondriales (P〈0.0001) is found. The morphological equivalents of this result are numerous stages of mitochondrial destruction including cristolysis. All myocardial weights were beyond the “critical heart weight”.
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  • 74
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    Neuroradiology 15 (1978), S. 79-84 
    ISSN: 1432-1920
    Keywords: Cerebral ventriculography ; Iodophendylate and metrizamide ; Electron microscopy ; Ependyma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cerebral ventriculography was performed on adult albino rats to compare the effect of metrizamide and iodophendylate on the ependymal wall. The animals were killed by vascular perfusion 1 month and 4 months after ventriculography. The ependymal layer and the underlying brain tissue were examined with the electron microscope. After the use of metrizamide the tissue appeared completely normal. The use of iodophendylate provoked accumulation of phagocytozing macrophages on the ependymal wall and storage of iodophendylate in the ependyma and underlying brain tissue. These changes were present both 1 and 4 months after ventriculography.
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  • 75
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    Calcified tissue international 25 (1978), S. 179-190 
    ISSN: 1432-0827
    Keywords: Decalcification ; Electron microscopy ; Calcified matrices
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The ultrastructure of calcifying cartilage and bone has been examined under the electron microscope after using three different methods of decalcification. The first was carried out before embedding (by soaking specimens in EDTA or formic acid), the second after embedding (by floating ultrathin sections on formic acid), and the third after embedding (by soaking embedded specimens in EDTA or formic acid), and with later re-embedding. The first procedure invariably induces drastic changes in the fine structure of the cells and calcified matrix, probably as a results of the extraction of organic material along with extraction of mineral. The second and third procedures make it possible to preserve ultrastructural details perfectly in both cells and calcified matrix. Of the two, the third procedure is preferable because of its greater simplicity. In areas that are still calcifying, these post-embedding decalcification techniques reveal the presence of crystal-associated, filamentous organic structures which are not recognizable in specimens decalcified before embedding. These structures, which could have a key role in inducing and regulating crystal formation and growth, are less evident in fully calcified areas (but not at their borders). This may partly be due to the loss of glycan components in the matrix during calcification. The most important determinant, however, seems to be the fact that during calcification the components of the matrix, including collagen fibrils, are involved in an aggregation process which reduces the amounts of free chemical groups available for reaction with the stain solution. Because post-embedding decalcification does not disturb this state of aggregation, the stainability of the matrix and the electron microscopic evidence of its components remain very low.
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  • 76
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    Calcified tissue international 26 (1978), S. 181-190 
    ISSN: 1432-0827
    Keywords: Cellular calcium ; Electron microscopy ; Osteoblasts ; Chondrocytes ; Mineralization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The calcium distribution in cartilage and bone cells during beginning ossification of fetal mouse long bones was studied after fixation with 2% K-pyroantimonate in 1% osmium. In the developing periosteum, the future osteoblasts showed a sparse cation-antimonate precipitate over the cytoplasm. In young osteoblasts the precipitate was accumulated on the mitochondrial membranes and the plasmalemma. Both organelles were sharply outlined by precipitate in the mature osteoblasts at the onset of mineralization. X-Ray microprobe analysis of these organelles demonstrated the presence of both Sb and Ca. In the extracellular compartment, a collagen-associated precipitate with 50 to 60 nm periodicity appeared during osteoblastic differentiation. During the initial phase of matrix mineralization, a random gross precipitate appeared in the matrix and seemed to be accumulated by osmiophilic matrix vesicles while the collagen fibrils lost their precipitate. Subsequently, during the confluent phase of matrix mineralization, the precipitate rapidly disappeared from the cells, leaving them devoid of precipitate once they were surrounded by mineralized matrix. Similar changes were found in the chondrocytes of the growth plate, but cartilage collagen, unlike osteoid collagen, did not bind precipitate. The results indicate that both osteoblasts and calcifying cartilage cells bind calcium prior to matrix mineralization. Bone collagen has strong pyroantimonate binding capacity, but it is not directly involved with initial stages of matrix mineralization, which starts in close association with matrix vesicles.
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  • 77
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    Archives of toxicology 41 (1978), S. 223-232 
    ISSN: 1432-0738
    Keywords: CeCl3-hepatotoxicity ; Hypolipidemic compounds ; Peroxisomes ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Pretreatment of rats with nafenopin, a hypolipidemic compound, prevents the lethality and hepatotoxicity induced by cerium chloride (CeCl3), a rare earth metal. The increase in hepatic triglycerides and the morphologic changes observed after 48 h of the CeCl3 injection (10 mg/kg) are completely abolished by nafenopin given for 4 days in doses of 250 mg/kg. However, an increase in the frequency of peroxisomes is noted in rats receiving nafenopin and CeCl3, attributable to the hypolipidemic drug pretreatment. In comparing the protective effect of nafenopin with that of CPIB (a structurally related compound) and lentysine (a structurally unrelated agent), it can be seen that nafenopin is about five times more active in decreasing liver triglycerides. The hepatic ultrastructure of rats pretreated with CPIB or lentysine is similar to that of CeCl3-treated controls.
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  • 78
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    Anatomy and embryology 152 (1978), S. 235-241 
    ISSN: 1432-0568
    Keywords: Chick embryo ; Lung maturation ; Influence of pituitary ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In order to discover whether the embryonic chick hypophysis acts upon lung maturation directly or via its corticotrophic activity, immature lung primordia were grafted into young hosts, either alone or associated with functional adrenals or pituitaries. When lung primordia were grafted alone, type II pneumocytes did not differentiate. Their differentiation was restored when lung primordia were grafted in association with either adrenals or pituitaries. This last result, which was also obtained in vitro, shows that the hypophysis is able, by itself, to promote the maturation of respiratory epithelium.
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  • 79
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    Anatomy and embryology 153 (1978), S. 23-36 
    ISSN: 1432-0568
    Keywords: Electron microscopy ; Quail embryo ; Rathke's pouch
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Adenohypophyseal region of quail embryo has been examined by electron microscopy from stage 12 to stage 21 of Zacchei (1961). The Seessel's pouch develops prior to the early stages of adenohypophysis formation, then regresses while Rathke's pouch proliferates and differentiates. From Rathke's pouch formation by stage 12 (48 h of incubation) until appearance of the first secretory granules by stage 21 (6 days of incubation), there are no major ultrastructural modifications in adenohypophyseal cells. Mitochondria, Golgi vesicles, polysomic ribosomes, pinocytotic vesicles, and mitotic figures become more numerous while nucleocytoplasmic ratio and the number of ribosomes and lipid droplets decreases. The major change is the appearance of secretory granules by day 6 of incubation. This phenomenon occurs at the same time as in chick embryo, despite an incubation period shorter for quail than for chick. Mitotic figures are mainly distributed near the pouch lumen, while secretory granules are first located in the peripheral cells of the cephalic part ofpars distalis primordium. The hypothetical role of mesenchyme and vascularization is discussed.
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  • 80
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    Archives of dermatological research 262 (1978), S. 301-309 
    ISSN: 1432-069X
    Keywords: Lymphatic vessel(s)-lv ; Localized lymphangioma circumscriptum-Lc ; Electron microscopy ; Lymphgefäße ; lokalisiertes Lymphangiom ; Elektronenmikroskopie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Lymphgefäße (lv) in einem lokalisiertem Lymphagiom (Lc) wurde elektronenmikroskopisch untersucht. Dieses Lymphangiom, das kein Hämangiom begleitete, wies klinisch ein typisches Bild auf, und zeigte histologisch keine entzündlichen Zeichen. Die Lymphgefäße in dieser Veränderung wurden morphologisch in zwei Typen eingeteilt. Die Lymphgefäße des ersteren Typs, die im oberen Corium lagen, zeigten wie bei der experimentell induzierten Lymph-Stauung, ähnliche Bilder während diejenigen im tieferen Corium, Ähnlichkeiten zu den des normalen Lymphgefäßes erkennen lassen. Aufgrund der in dieser Untersuchung erlangten Befunde und unter Berücksichtigung der Literaturen ließ sich ableiten, daß dieses lokalisierte Lymphagiom nicht als ein echter gutartiger Tumor betrachtet wurde, sondern durch eine dauernde Lymph-Stauung in einem tumorartigen Zustand gehalten wurde.
    Notes: Summary An electron microscopic study was performed on the lymphatic vessel (lv) of localized lymphangioma circumscriptum (Lc), which was found clinically typical but histologically not associated with hemangioma and inflammation. The lv of Lc was morphologically divided into two types. The first type was situated at the upper dermis of the lesion and the other, at the deep dermis. The former had certain similarities to lv of experimentally induced lymph-stasis, whereas the latter was morphologically similar to lv of the normal skin. From the findings of the present study and those reported in literature, Lc could not be considered as a mere benign overgrowth of lv, but as one of pathological results induced by a long-standing lymph-stasis.
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    Archives of dermatological research 262 (1978), S. 83-96 
    ISSN: 1432-069X
    Keywords: Keratohyalin ; Keratinization ; Wart ; Papilloma ; Rat tongue ; Electron microscopy ; Osmium tetroxide ; Hydrogen peroxide ; Pepsin ; Keratohyalin ; Keratinisation ; Warzen ; Papillom ; Rattenzunge ; Elektronenmikroskopie ; Osmiumtetroxid ; Hydrogenperoxid ; Pepsin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Heterogenität von Keratohyalin wurde in der Rattenzunge und in menschlichen Warzen dargestellt. Beide zeigen morphologische Ähnlichkeiten, wie dichte homogene ovoide einzelne Granula und zusammengesetzte Granula, die offenbar aus einzelnen Granula sich ableiten und von einer Membran überzogen sind. Die Ultrastruktur dieser Keratohyalinkörper wurde durch Fixierung mit Osmiumsäure nach Oxydation mit H2O2 und nach Pepsinbehandlung verglichen. Die einzelnen Granula sind osmiophil, während die zusammengesetzte Granula diese Eigenschaft nicht zeigen. Bei menschlichen Warzen zeigte sich eine fehlende Oxydierung durch H2O2 der einzelnen Granula, während die zusammengesetzten Granula oxydationsempfindlich sind. In der Zunge von neugeborenen Ratten zeigten sich die umgekehrten Verhältnisse. Diese Unterschiede zeigen, daß es unmöglich ist, die Bildung von Keratohyalingranula auf dem gleichen Wege zu erklären, wie die der Keratohyalingranula bei den Ratten, obwohl ultrastrukturelle Ähnlichkeiten bestehen. Es erscheint wichtig darauf hinzuweisen, daß die Keratogenese und die Keratohyalingranulabildung, die bei den Verrucae vulgaris vorliegt, von der Keratohyalinentwicklung in der Rattenzunge sich unterscheidet.
    Notes: Summary The heterogenecity of keratohyalin (KH) has been demonstrated in rats, then in human warts where similar morphological features have been found and among them, dense homogeneous ovoïd single granules (SG) and composite granules (CG) apparently made up of single granules “coated” with a matrix. This work compares the ultrastructure of the KH of the tongue of newborn rats with that of common warts with and without post-fixation by OsO4, after oxydation by H2O2 and after pepsin treatment. The osmiophily of the SG is confirmed as well as the absence of osmiophily of the matrix of the CG. In man, however, the SG are resistant to oxydation by H2O2 and the CG matrix is oxydation sensitive whereas the opposite is observed in the case of rats. These differences show that it is impossible to deduce the composition of the KH in human warts from that of the rat despite their close ultrastructural resemblance but that important modification of the keratogenesis and KH formation are induced in the cells parasited by the virus of common warts.
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    Archives of dermatological research 263 (1978), S. 227-233 
    ISSN: 1432-069X
    Keywords: Erythrocytes ; Painful bruising syndrome ; Freeze-etching ; Electron microscopy ; Rote Blutzellen ; ≫Painful bruising≪-Syndrom ; Gefrierätzung ; Elektronen-Mikroskopie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei 3 Patienten mit dem Gardner-Diamond Syndrom oder dem ≫painful bruising≪-Syndrom sind morphologische Abweichungen an roten Blutzellen festgestellt worden. Von diesen roten Zellen, die bei der Ficoll/Isopaque Gradient Zentrifugation nicht sedimentierten, werden teilweise keulenförmige Ausläufer, Mitochondrien, Kernreste und Vacuolen festgestellt. Bei pH 7.4 zeigten 90% der roten Blutzellen in Gefrierätzparaten Ausbuchtungen auf der Membran, während bei pH 6,4 noch 25% der roten Zellen diese Erhebungen zeigten. Im Kontrolpräparaten waren diesen Zahlen 55% und 0% unterschiedlich bei pH 7.4 und 6.4. Die Geldrollenbildung im Blut von Patienten mit dem ≫painful bruising≪-Syndrom war stark erhöht.
    Notes: Summary Red cells of 3 patients with the painful bruising syndrome showed morphological anormalities. In the fraction not sedimenting in Ficoll/Isopaque gradient centrifugation, some of these cells had club-shaped processes, mitochondria, nuclear remnants, and vacuoles. In freeze-etch preparations, 90% of the red cells showed membrane elevations at pH 7.4 and 25% at pH 6.4, while in freeze-etch preparations of controls these values were 55 and 0 respectively. In addition, rouleaux formation was markedly enhanced in the preparations of blood of patients with the painful bruising syndrome.
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    Anatomy and embryology 153 (1978), S. 287-293 
    ISSN: 1432-0568
    Keywords: Mouse embryos ; Visceral yolk sac ; Trypan blue ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructural features of the early visceral yolk sac epithelium of normal mouse embryos on day 9 were compared to those whose mothers had received a single subcutaneous injection of 100 mg/kg trypan blue on day 8. The following results were obtained: In normal embryos the visceral yolk sac cells are predominantly characterized by numerous membrane bounded inclusions localized in the supranuclear cytoplasm. In embryos of animals treated with trypan blue, at about 12h after injection large single and only partly membrane bounded vacuoles are observed occupying most of the apical cytoplasm. Up to 24h after injection large cytoplasmic areas are seen which are in a stage of autodigestion possibly due to leakage of the vacuolar content. These alterations are exclusively limited to the visceral yolk sac epithelium whereas in the cells of the embryonic part, e.g. head process, no changes could be found. The observations are discussed in relation to the mechanism of the teratogenic activity of trypan blue.
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  • 84
    ISSN: 1432-0568
    Keywords: Myofibrillogenesis ; Human heart ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The myofibrillogenesis in the human embryonic heart is described. The synthesis of thin filaments, which are the first to appear, takes place in close proximity to smooth surfaced SR tubules. Z-band material is closely related to the thin filaments and appears first as irregularly distributed patches in the filamenteous mass. Further cellular differentiation includes an organization of the thin filaments/Z-band material. The synthesis of thick filaments, which follows that of the thin filaments, takes place in ribosome rich areas of the cell. They are rapidly incorporated into the strings of organized thin filaments/Z-band material. The periodic binding sites on both kinds of filaments are believed to play an important role in the precise ordering of the filaments. The formation of myofilaments in the adult hypertrophied human heart is also described. The similarities between this process and that observed in the embryonic heart are striking, and we believe it to be the same process.
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    Anatomy and embryology 152 (1978), S. 223-234 
    ISSN: 1432-0568
    Keywords: Chick embryo ; Lung maturation ; “in ovo” decapitation ; Lung lipids ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of “in ovo” hypophysectomy on lung maturation of the chick embryo were investigated. Both biochemical and morphological aspects of differentiation were markedly delayed in experimental embryos: the phospholipid content of lungs was lower than in controls at all stages, whereas the water content remained very high. The type II pneumocytes, which normally appear within the epithelium on day 16 of incubation, started to differentiate only between days 18 and 20 of incubation in the decapitated embryos. The differentiation of type I pneumocytes leading to the formation of air capillaries was also slowed down: they did not appear until the end of incubation in decapitated embryos, whereas they normally start to appear on day 19. The presence of an intact hypophysis is thus essential for normal lung maturation in the chicken.
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  • 86
    ISSN: 1432-0533
    Keywords: Toxoplasma gondii ; Encephalitis ; Central nervous system ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure and reproductive mechanisms of Toxoplasma gondii are described in a case of toxoplasma encephalitis. Replication was observed in glial cells by an internal budding process: endodyogeny. Distinctive ultrastructural features associated with host cell penetration, and encystation are described. Electron microscopic features previously reported in tissue culture and in experimentally produced infections with T. gondii are confirmed in the human brain tissue.
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  • 87
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    Acta neuropathologica 42 (1978), S. 121-126 
    ISSN: 1432-0533
    Keywords: Nerve fiber teasing ; Phase contrast microscopy ; Electron microscopy ; Axonal and myelinic disorder ; Wallerian degeneration ; Secondary segmental demyelination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The changes in a sural nerve biopsy of a patient with porphyric neuropathy were studied by light and electron microscopy. Linear arrays of myelin ovoids constituted the most common abnormality in whole mounts of teased-fiber preparations. Round or irregular formations of variable osmiophilia were the most frequent finding in thick-section preparations examined by phase contrast microscopy. Lamellar whorls represented the most prevalent lesion in thinsections studied under the electron microscope. In addition, along the teased fibers, segmental demyelination was definitely detected, although rarely; in thick sections, the true extent of the nerve fiber loss was fully appreciated; in thin sections, a variety of axon and myelin changes of a distinct character were discovered. The studies demonstrate that in peripheral nerves of porphyric neuropathy, axonand myelin changes generally run together and proceed pari passu in the same segment of nerve fiber. Furthermore, among the pathogenetic mechanisms invoked to account for the neuropathic changes none are favored to the exclusion of others by these studies. Therefore, a primary axonaland myelinic disorder on the basis of a deranged porphyrin metabolism is as good a possibility as any hitherto advanced explanation of the pathogenesis of the neuropathic changes. The secondary lesions of Wallerian degeneration and segmental demylination may simple be grafted upon the primary lesions evoked by the metabolic abnormality.
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  • 88
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    Acta neuropathologica 42 (1978), S. 211-215 
    ISSN: 1432-0533
    Keywords: Canine CNS ; Myelination ; Hypomyelinogenesis ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Five Chow-Chow dogs from three different litters had generalized body tremors since birth. Histologically a severe myelin deficiency was found in the central nervous system. The peripheral nerves were normally myelinated. Electron microscopically abnormally thin myelin sheaths and completely naked nerve fibers were found. There were many astrocytes in the myelin deficient areas as well as cells with the characteristic features of oligodendrocytes but also containing fibrils. The present cases are compared to other dysmyelinating diseases and possible pathogenetic mechanisms are discussed.
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  • 89
    ISSN: 1432-041X
    Keywords: Synaptogenesis ; Electron microscopy ; Visual acuity ; Fish development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The morphogenetic differentiation of synapses of the optic tectum of the rainbow trout was investigated at different stages of development (from hatching to adult) and compared with the improvement in visual discrimination (minimum separable). (1) The main phase of synaptogenesis (increase in number of synapses, length of contact zone and number of vesicles) begins about one week after hatching and continues up to the age of one month, when the larvae start swimming freely. (2) Myelination begins 26 days after hatching and induces the end of the synaptogenesis period. (3) The visual discrimination (minimum separable) of trout larvae improves from 30 degrees of arc on the 10th day after hatching to 1 degree on day 30, then to about 14 to 18 min of arc in the adult. The results are discussed with special reference to previous biochemical investigations on changes in the ganglioside composition of the trout brain during comparable periods of development.
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    Calcified tissue international 25 (1978), S. 133-143 
    ISSN: 1432-0827
    Keywords: Osteon ; X-Ray diffraction ; Electron microscopy ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary To obtain information on the changes in the inorganic bone fraction during calcification, low- and wide-angle X-ray diffraction techniques and electron microscopy have been applied to single osteon samples. The samples were cylindrically shaped and their axes corresponded to the axes of the Haversian canals. The selection was made according to the degree of calcification and the orientation of collagen bundles and inorganic particles. Osteons at both the initial and final stages of calcification were chosen. Arrangements of fiber bundles and inorganic particles in successive lamellae characteristic of three types of osteon were selected, that is, longitudinally structured osteons, transversely structured osteons, and alternately structured osteons. The results indicate that in osteonic lamellar bone there are two types of inorganic particles: (1) granules arranged in linear or needle-shaped entities with maximum width 40–45 Å, which are regularly distributed at the level of the main band of the collagen fibrils where their maximum length reaches the length of the main band itself; that is, about 400 Å; and (2) very long crystallites, with a diameter of 40–45 Å, which grow with their crystallographicc-axis parallel to the collagen fibrils and cover much more than a major collagen period.
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    Calcified tissue international 25 (1978), S. 217-222 
    ISSN: 1432-0827
    Keywords: Bone mineral ; Electron microscopy ; X-ray diffraction ; Dark field
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Electron microscopical observations of the size and shape of bone mineral crystallites have not been in complete agreement with X-ray diffraction findings. The two prevalent viewpoints consider bone mineral crystals to be either rod, or plate like in habit. There appears to be agreement that the smallest dimension of the crystals is about 5 nm, but there is discrepancy in the reported c-axial lengths. The method of dark field imaging is used to obtain a quantitative measurement of the c-axial length distribution in rabbit, ox and human bone: mean c-axial lengths 32.6 nm, 36.2 nm and 32.4 nm, respectively, show no significant difference at the 5% level to the mean c-axial length measured by X-ray line broadening. Both bright and dark field images strongly suggest that bone mineral has a plate like form. Reasons for past discrepancies are discussed.
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  • 92
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    Calcified tissue international 25 (1978), S. 45-51 
    ISSN: 1432-0827
    Keywords: CaCO3 ; Amino acids ; Sheaths ; Ligament ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The aragonite crystals in the molluscan bivalve hinge ligament are surrounded by an organic sheath which is distinct from the remainder of the ligament matrix. Methods have been developed to isolate these sheathed crystals from the ligaments ofSpisula solidissima andMercenaria mercenaria employing a papain digestion of the matrix protein. The sheathed crystals fromSpisula have a CaCO3/protein ratio of 11.1 and those fromMercenaria a ratio of 29.6. The sheathed crystals and the empty crystal sheaths have been examined by electron microscopy for structural integrity. The sheath proteins exhibit much smaller proportions of the amino acids glycine and methionine than the hinge ligaments. These are characteristic amino acids of high concentration in the hinge ligaments of both species. The concentrations of acidic and basic amino acids are increased about two fold in the sheaths over those of the ligaments. Otherwise there is little similarity in the amino acid composition of the sheaths in the two species. However, SDS electrophoresis shows the sheaths of both to contain a major protein component with a molecular weight of about 25,000. The sheath protein from theMercenaria ligament contains about 5% carbohydrate and that ofSpisula sheaths less than 1% carbohydrate.
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    European journal of pediatrics 127 (1978), S. 75-89 
    ISSN: 1432-1076
    Keywords: Hyperinsulinism ; β-cell hyperplasia ; Nesidioblastosis ; Newborn ; Infants ; Somatostatin ; Electron microscopy ; Therapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two patients with severe hypoglycemia since birth are described. In both hyperinsulinism was demonstrated during spontaneous hypoglycemic attacks or could be provoked by various tolerance tests. In case I considerable obesity and psychomotor retardation was present at the age of one year whereas in case II weight gain was normal and development unaffected. Immunofluorescence microscopic and electron microscopic examination of the pancreas after subtotal pancreatectomy revealed diffuse islet cell hyperplasia with nesidioblastosis in case I and β-cell nesidioblastosis in case II. The hyperplastic and nesidioblastotic areas consisted mainly of β-cells. In addition, an accumulation of somatostatin producing cells was observed in case I, and some cells were found with ultrastructural signs of both endocrine and exocrine function. In both cases, pancreatic insulin release was inhibited by a prolonged somatostatin infusion. The results of tolerance tests did not allow a diagnosis of the underlying pancreatic lesion. In case II, leucine-sensitive hypoglycemia detected soon after birth, was present even after subtotal pancreatic resection. Therapeutic trials with diazoxide in case I and a leucine-restricted diet in case II were only of temporary benefit. After subtotal pancreatectomy there was clinical improvement in both cases, but case II still needs a leucine-restricted diet. The familial occurrence of persistent hypoglycemia in both cases suggests that β-cell nesidioblastosis may be a hereditary disorder.
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  • 94
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    Archives of dermatological research 261 (1978), S. 7-16 
    ISSN: 1432-069X
    Keywords: Erythema elevatum diutinum ; Extracellular cholesterosis ; Electron microscopy ; Lipid deposition ; Vasculitis ; Erythema elevatum diutinum ; Extracelluläre Cholesterinose ; Elektronenmikroskopie ; Lipidablagerung ; Vaskulitis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Ein typischer Fall von Erythema elevatum diutinum (E.e.d.) mit extracellulärer Cholesterinose bei einer 48jährigen Patientin mit bisher 15 Jahre dauerndem Verlauf wird klinisch und histologisch beschrieben. 2. Elektronenmikroskopisch wird die histologisch und immunfluorescenzmikroskopisch nachgewiesene leukocytoklastische Vaskulitis bestätigt. In älteren Herden herrschen Histiocyten/Makrophagen vor. Intra- und extracelluläre Lipidablagerungen erscheinen elektronenmikroskopisch unter verschiedenartigen Bildern, die sich in ihrer Gesamtheit von allen anderen bisher ultrastrukturell beschriebenen Krankheiten mit Lipidablagerungen unterscheiden. 3. Die Befunde sind mit der Hypothese vereinbar, daß primär bei E.e.d. eine besondere Form von chronischer leukocytoklastischer Vaskulitis vorliegt und die Lipidablagerungen sekundär auf dem Boden von Gefäßwandschädigungen und Nekrosen entstehen.
    Notes: Summary 1. A typical case of Erythema elevatum diutinum (E.e.d.) with extracellular cholesterosis is described clinically and histologically in a 48-year-old woman. The disease had a course of 15 years. 2. Electron microscopy confirmed the histological and immunfluorescent findings of leucocytoclastic vasculitis. In older lesions, histiocytes/macrophages predominate. Intra- and extracellular lipid depositions showed a variety of ultrastuctural characteristics which differed from electron microscopical findings described in other disorders associated with lipid deposition. 3. The findings are in accordance with the hypothesis that the primary event in E.e.d. is a special type of chronic leukocytoclastic vasculitis. Subsequently, the damage of the vessel walls and focal necrosis may lead to secondary lipid deposition.
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  • 95
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    Archives of microbiology 119 (1978), S. 303-304 
    ISSN: 1432-072X
    Keywords: Vibrio cholera phage group II ; Properties ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The basic physical, chemical and physiological properties of a group II cholera phage belonging to Mukerjee's classification has been described.
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  • 96
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    Archives of microbiology 119 (1978), S. 227-229 
    ISSN: 1432-072X
    Keywords: Cell wall ; Electron microscopy ; Methylomonas albus ; Goblet sub-units
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In surface view, the cell wall complex ofMethylomonas albus possesses a hexagonal pattern of ridges. Thin sections reveal a continuous layer of goblet-shaped elements attached to the outermost surface of the lipopolysaccharide membrane. A possible interpretation of the cell wall complex ofM. albus, based on the fine-structural data is presented.
    Type of Medium: Electronic Resource
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  • 97
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    Archives of microbiology 116 (1978), S. 133-139 
    ISSN: 1432-072X
    Keywords: Lagenisma ; Coscinodiscus ; Infection ; Endosymbiotic bacteria ; Tip growth ; Wall-less thallus ; Host-parasite interface ; Membranes ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Lagenisma coscinodisci is diplanetic and has two different cyst stages. The secondary cyst has a uniform cell wall of fibrillar material. It attaches to a Coscinodiscus frustule and germinates with an infection tube. The cyst becomes filled with an enlarging expulsion vacuole. The infection tube penetrates the diatom cell between the cingula. Inside the host cell the fungus grows as an irregularly branched wall-less thallus. In the hyphae apical vesicles are lacking. The infection tube is plugged by wall material. There are no microtubules which might participate in the morphogenesis of the thallus. The plasmalemma of the diatom is pushed inward but not pierced by the fungus. Along the host-parasite interface it lies closely paralled to the Lagenisma plasmalemma which is extremely straight here and measures about 10 nm instead of about 5–6 nm at the surfaces of other stages. The Coscinodiscus plasmalemma disintegrates at about the same time when the cytoplasm breaks down. The fungus allows bacteria to enter the diatom; there are also endosymbiontic bacteria in unattacked cells — The growth mechanisms are discussed and the host-parasite interface is compared with that of other fungi.
    Type of Medium: Electronic Resource
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  • 98
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    Archives of microbiology 118 (1978), S. 67-69 
    ISSN: 1432-072X
    Keywords: Corynebacterium autotrophicum ; Outer Membrane ; Lipopolysaccharides ; Biochemical analysis ; Polymyxin B ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Lipopolysaccharides (LPS) from Corynebacterium autotrophicum were isolated and analyzed. Autotrophically grown cells contained 2–5 mg of partly purified LPS per g dry weight of lyophilized cells. Serological cross reaction with Lipid A antigen of Salmonella minnesota confirmed the presence of LPS in C. autotrophicum. Electron microscopy of negatively stained Polymyxin B-treated cells showed formation of blebs on the Outer Membrane indicating an interaction of Polymyxin B specifically with LPS. Up to now, no Gram-positive organisms are known which contain any LPS. Thus, C. autotrophicum, though giving opposite results when the Gram-staining reaction was applied by several authors, has to be classified into the group of Gram-negative bacteria.
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  • 99
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    Archives of microbiology 118 (1978), S. 305-308 
    ISSN: 1432-072X
    Keywords: Carotenoid mutant strain R-26-Rhodopseudomonas sphaeroides ; Electron microscopy ; Intracellular membranes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Stained thin-sections and freeze-fractured preparations of the carotenoid-less mutant strain R-26 of Rhodopseudomonas sphaeroides grown photosynthetically revealed 2 morphological kinds of intracellular membrane systems- spherical vesicles distributed throughout the cytoplasm and lamellae confined to the periphery of the cell. The lamellar membranes appeared to be large, flattened vesicles.
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  • 100
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    Archives of microbiology 119 (1978), S. 87-90 
    ISSN: 1432-072X
    Keywords: Salmonella typhimurium strain LT2 (ColIb) ; Cryptic plasmids ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Small cryptic plasmids of molecular weights ranging from 1 to 3 Mdal were detected by electron microscopy in Salmonella typhimurium strain LT2 (ColIb). They were divided into different size classes. Two of the cryptic plasmids were transferred simultaneously with ColIb to Escherichia coli.
    Type of Medium: Electronic Resource
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