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  • 2015-2019
  • 2000-2004  (56)
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  • 101
    ISSN: 1434-0879
    Keywords: Malignant fibrous histiocytoma ; Sarcomatoid carcinoma ; Urinary tract ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An immunohistochemical analysis using antibodies to cytokeratin, epithelial membrane antigen, alpha-1-antitrypsin, alpha-1-antichymotrypsin and factor XIIIa was performed in four cases of malignant fibrous histiocytoma and five cases of sarcomatoid carcinoma in the urinary tract. All cases of malignant fibrous histiocytoma showed positive staining for factor XIIIa, alpha-1-antitrypsin and alpha-1-antichymotrypsin. No case was positive for factor XIIIa, but one case with sarcomatoid carcinoma stained positive for alpha-1-antitrypsin and alpha-1-antichymotrypsin. All cases showed positive staining for cytokeratin and 4 cases with sarcomatoid carcinoma were positive for epithelial membrane antigen, but no cases with malignant fibrous histiocytoma were positive. Immunohistochemical analysis would thus help to distinguish malignant fibrous histiocytoma from sarcomatoid carcinoma of the urinary tract.
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  • 102
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 184 (1991), S. 181-193 
    ISSN: 1432-0568
    Keywords: Dorsal column nuclei ; GABA ; Immunohistochemistry ; Interneurons ; Light microscopy ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The gracile and internal and external cuneate nuclei of four adult cats were studied, using recently developed stereological techniques. The length, volume and position of the nuclei in relation to the level of obex were calculated, as well as the number of neurones, the neuronal density and volume of the three nuclei and different regions in the gracile and internal cuneate nucleus. Material processed for GABA immunocytochemistry was used in order to compare GABAergic and non-GABAergic neurones. The results demonstrate variations in the same nucleus in different animals, and in the nucleus of the left and right sides of the same animal. The same nucleus can vary up to 4 mm in its rostrocaudal position in relation to the obex. The mean sizes of the gracile, internal and external cuneate nuclei are 4.2, 8.4 and 5.6 mm', respectively and their mean neuronal numbers are about 52000, 76 000 and 33000, respectively. The neuronal density was highest (12907 cells/mm3) in the gracile, and lowest in the external cuneate nucleus (5987 cells/mm3). The external cuneate nucleus had a larger relative volume (7.9%) occupied by nerve cell bodies compared with the two medial nuclei (5.1% and 5.8%). In the gracile and internal cuneate nuclei, the GABAergic neurones constituted 28% and 25% of the whole population, respectively, while the external cuneate nucleus was devoid of such cells. All the nuclei contained GABA-positive boutons, however. The mean volume of the GABA-stained neurones in the gracile nucleus was 2319, and internal cuneate 3065 μm3, while the corresponding volume of unlabelled neurones in the gracile, internal and external cuneate nuclei was 3745, 8147 and 13 318 μm3, respectively. When cyto-fibro-architectonic characteristics were used to subdivide the gracile and cuneate nuclei into rostral, middle and caudal regions, and the data of the three compartments compared, it was found that in both nuclei the middle region had the highest neuronal packing density, and the caudal region the largest mean nerve cell volume.
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  • 103
    ISSN: 1432-0533
    Keywords: Brain ; Cerebral ischemia ; Gerbil ; Immunohistochemistry ; Hippocampus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Anesthetized Mongolian gerbils were subjected to 5-min ischemia and 8 h of recirculation. Vibratiom sections were taken for studying changes in ornithine decarboxylase (ODC) immunoreactivity using an antiserum to ODC, and tissue samples were taken for measuring ODC activity. After 5-min ischemia and 8-h recirculation ODC activity increased 11.5-, 5.9-, and 7.9-fold in the cerebral cortex, striatum and hippocampus, respectively (P≤0.05 to 0.01). In the cortex, striatum and hippocampus of control animals immunoreactivity was low but clearly above the detection limit. The reaction was confined to neurons. After 5-min ischemia and 8-h recirculation a sharp increase in immunoreactivity was observed confined to neurons, indicating that the postischemic activation of polyamine metabolism is a neuronal response to ischemia. The immunoreactivity was markedly increased in the perinuclear cytoplasm and the dendrites. In the striatum the density of neurons exhibiting a sharp increase in immunoreactivity was more pronounced in the lateral than in the ventral part. In the hippocampus a strong reaction was present in all subfields but the CA1 subfield was particularly affected. The present study demonstrates for the first time that biosynthesis of a protein is markedly activated during the first 24 h of recirculation after 5-min cerebral ischemia of gerbils even in the vulnerable CA1 subfield, in which the overall protein synthesis is sharply reduced at the same time. Studying polyamine metabolism after ischemia may, thus, provide new information about the basic molecular mechanisms responsible for the altered gene expression after metabolic stress.
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  • 104
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 81 (1991), S. 503-509 
    ISSN: 1432-0533
    Keywords: Rosenthal fibers ; Ubiquitin ; Immunohistochemistry ; Glial fibrillary acidic protein ; Vimentin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Seventeen intracerebral gliomas containing Rosenthal fibers (RF) were studied by an immunoperoxidase method for localization of ubiquitin (UB), glial fibrillary acidic protein (GFAP), desmin and vimentin (VIM). The majority of RF showed an immunohistochemically negative core surrounded by a ring of overlapping reactions for UB, GFAP and VIM. Many RF were entirely negative for UB and intermediate filaments (IF). Immunoelectron microscopic lozalization of UB and GFAP was performed on seven selected tumors. UB was found in all RF and on IF in the proximity of RF. GFAP reaction was localized on astrocytic IF, including those trapped within RF, and within the granular component of some RF. In contrast to the light microscopic studies, neither GFAP-nor UB-negative RF were found on immunoelectron microscopy. VIM reaction on IF and a few RF was demonstrated in one tumor processed at low temperature into Lowicryl; it was much weaker than that for GFAP. Many cells with RF contained lysosome-like inclusions with material displaying electron density similar to adjacent RF; few of these inclusions were reactive for UB. It is concluded that RF formation is associated with ubiquitination of astrocytic IF. GFAP-and VIM-immunoreactive IF and products of their disintegration contribute to RF material. It is also suggested that the lysosomal system of astrocytes partially degrades RF.
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  • 105
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 183 (1991), S. 415-426 
    ISSN: 1432-0568
    Keywords: Progesterone receptor ; Chick embryo ; Ur ; ogenital system ; Immunohistochemistry ; Spinal cord
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The early appearance, cellular distribution, and hormonal regulation of the progesterone receptor was studied in the urogenital tract of the chick embryo using antibodies to the receptor molecule. In embryos at day 5 of incubation the receptor is revealed in cell nuclei of the mesenchyme and the coelomic epithelium near the primordium of the urogenital sinus. In embryos at days 6 to 10 immunostained cells are found in the mesenchyme surrounding the urodeal and proctodeal epithelia. The first difference between male and female embryos appears at day 8, with a higher density of progesterone receptor-containing cells along the urogenital sinus epithelium in females. The female type of receptorpositive cell distribution can be induced in males by oestradiol treatment. Anti-oestrogens applied from day 0 of incubation do not prevent or delay the appearance of PR, but induce a male-type distribution in female embryos. In the gonads, immunostained cells appear unambiguously at day 6 in the medulla. At later stages, the receptor is revealed mostly in the medulla, although there are also positive cells in the cortex of the left ovary. The immunoreactivity is not significantly modified by oestradiol or anti-oestrogens. The mesonephros is devoid of immunoreactivity, whereas most cells of the metanephric mesenchyme are receptor-positive. In the Mullerian ducts progesterone receptor is not detected in control embryos of either sex until after day 10. Between days 6 and 7 Mullerian ducts become responsive to oestradiol, which induces progesterone receptor in luminal epithelial cells. In the spinal cord, receptor is detected in neurones of the ventral horn and the meninges, starting at day 6. The progesterone receptor is up-regulated by oestradiol in the mesenchymal cells, Mullerian ducts, and mesothelium, but not in the gonads or the spinal cord. In none of the tissues or organs where the receptor appears naturally during development could an anti-oestrogen treatment with Tamoxifen or RU39411 block or delay its constitutive appearance. The widespread and specific distribution of the progesterone receptor, its programmed appearance in various organs, and its precise hormonal regulation, are in favour of a morphogenetic role of progesterone in tissue differentiation, related or not to sexual differentiation of the urogenital tract.
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  • 106
    ISSN: 1432-0568
    Keywords: Tyrosine hydroxylase ; Immunohistochemistry ; Amacrine cells ; Development ; Retinal growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The development of neurons immunoreactive to tyrosine hydroxylase (TH-IR) in the retina ofXenopus laevis was investigated from stage 53 tadpoles to adult, by using an antibody against tyrosine hydroxylase. At all developmental stages, most of the immunoreactive somata were located in the inner nuclear layer, and a few in the ganglion cell layer. Immunoreactive processes arborised in the scleral and vitreal sublaminae of the inner plexiform layer, indicating that these cells were bistratified amacrine cells. However, occasionally a few immunoreactive processes were observed projecting to the outer plexiform layer, suggesting the presence of THIR interplexiform cells. The number of immunoreactive amacrine cells in the inner nuclear layer per retina increased from 204 at stage 53 tadpole to 735 in adult, while the number of immunoreactive amacrine cells in the ganglion cell layer did not change significantly over the same period. Retinal area increased from 1.95 mm2 at stage 53 to 23.40 mm2 in the adult, and correspondingly cell density in the inner nuclear layer decreased from 104/mm2 to 31/mm2. At all stages there was an increasing density towards the ciliary margin, but this gradient decreased with age. The soma size of immunoreactive amacrine cells increased with age, and was consistently larger in the central than in the peripheral retina. Dendritic field size was estimated to increase 13-fold, from stage 53 to adult. This study shows that tyrosine hydroxylase-like immunoreactive amacrine cells are generated continuously throughout life, that after metamorphosis the retina grows more by stretching than by cell generation at the ciliary margin, and that the increase of dendritic field size is proportional to the increase in retinal surface area.
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  • 107
    ISSN: 1432-0533
    Keywords: Immunohistochemistry ; Brain tumors ; Proliferation kinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The monoclonal antibody (mAb) Ki-67 is a marker for the growth fraction (GF) of tumor cells. The exact relationship between the Ki-67 labeling index (LI) and the conventional diagnostic criterion of the proliferative activity of brain tumors, the mitotic index (MI), is unknown except for some general references. On serial frozen sections Ki-67 LI and MI were determined in nearly identical areas of 32 glioblastomas, 20 grade III astrocytomas, 21 grade II astrocytomas and 20 selected cases of meningioma. The data not only clearly showed different median values of LI and MI for the various malignancy grades, but also similar regression coefficients for each glioma type. A non-linear relationship between the two indices was found for all glioma cases with high significance and high correlation coefficient; (LI)=5.6 (MI)0.59. This results from differing intermitotic cycle times, the variability of which can be estimated from the data given.
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  • 108
    ISSN: 1432-0533
    Keywords: Membranous lipodystrophy ; Thalamic degeneration ; Neuropathology ; Autopsy ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An autopsied case of membranous lipodystrophy (Nasu-Hakola disease, NHD) with thalamic degeneration was reported. A 34-year-old Japanese man was diagnosed as having NHD by bone biopsy prior to the onset of clinical symptoms. His maternal grandfather and paternal grandmother are cousins, but this family history is negative for NHD. He developed frontal lobe syndrome at the age of 35 with progressive dementia, and died of acute renal failure at the age of 46. Gross inspection of the brain detected atrophy and softening of the cerebral white matter, predominantly in the frontal lobe. Microscopically, numerous spheroids, predominant fibrillary gliosis with less prominent demyelination “dissociation glio-myélinique” and scanty sudanophilic lipid droplets were observed, indicating the sclerosing type of NHD. An unusual pathological finding in this case was selective involvement of the thalamic nuclei with preservation of the other gray matter except for focal cortical necrosis. The topography of the affected thalamic nuclei is similar to that of systemic thalamus degeneration. An association with thalamic degeneration in NHD has not been previously reported. The present case suggests that NHD also affects the thalamus.
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  • 109
    ISSN: 1432-0533
    Keywords: 72-kDa heat-shock protein ; Neuronal necrosis ; Forebrain ischemia ; Immunohistochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We evaluated the relationship between the induction of the 72-kDa heat-shock protein (hsp 72) and the presence of necrotic neurons in the rat hippocampus, 48 h after an 8-min episode of forebrain ischemia in eight rates. Hsp 72 was detected using the monoclonal antibody C92 on vibratome brain tissue sections. Hematoxylin and eosin (H&E) staining on adjacent paraffinembedded sections was used to determine histopathological features. All morphologically intact CA1/2 neurons, 70% of which are destined to become necrotic 7 days after ischemia, exhibited intense hsp 72 staining, while necrotic or damaged neurons were devoid or low in hsp 72. Hsp 72 was also detected in CA3 neurons destined to survive 7 days after ischemia. Blood vessels positive for hsp 72 were detected in focal brain regions, in which severely damaged neurons were either devoid or low in hsp 72 staining. Occasional glial cells expressed hsp 72 in both normal and damaged brain regions. Hsp 72 response to a transient forebrain ischemia seemingly reflects differences in the selective ischemic vulnerability of CA1/2 and CA3 neurons. Further, the presence of hsp 72 within a neuron is likely only a marker of stress and is not necessarily indicative of eventual neuronal survival.
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  • 110
    ISSN: 1432-0533
    Keywords: Proliferating cell nuclear antigen (PCNA) ; Ki-67 ; Immunohistochemistry ; Nervous system tumors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Proliferating cell nuclear antigen (PCNA) is a 36-kDa DNA polymerase-σ auxiliary protein which accumulates in the nucleus during S phase of the cell cycle. Immunohistochemical labeling indices (LI) of PCNA and Ki-67 were compared using an avidin-biotin complex method on frozen sections of 27 nervous system tumors, 3 normal cerebral cortices, and 3 peripheral nerves. In glial tumors, PCNA and Ki-67 LI increased with increasing tumor grade (Daumas-Duport system). In 5 low-grade glial tumors, PCNA and Ki-67 LI were ≤1%, except for one optic nerve glioma (Ki-67 LI=6%). In 7 grade 3 astrocytomas, and 1 mixed glioma, PCNA LI were ≤1–1.5%, while Ki-67 LI were 2%–10%. In 7 grade 4 astrocytomas and 1 metastatic carcinoma, PCNA LI ranged from 6%–15% while Ki-67 LI ranged from 17%–30%. In 5 of 6 schwannomas, focally high PCNA LI (4%–65%) were noted, despite low LI with Ki-67 (≤1.6%). Scattered normal schwann cell nuclei also stained with PCNA, but normal cerebral cortex did not. These data suggest that: (1) in higher-grade gliomas, PCNA may be a more specific S-phase marker, although a less sensitive proliferation marker, than Ki-67; (2) PCNA LI do not distinguish low-grade gliomas from grade 3 astrocytomas; (3) in schwannomas, PCNA may not reflect proliferative activity since it seems to react with an epitope present in normal schwann cells; and (4) the variable PCNA staining pattern introduces greater difficulties in cell counting than with Ki-67. These factors may limit the use of this anti-PCNA antibody in evaluating nervous system tumors.
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  • 111
    ISSN: 1432-0568
    Keywords: Rat larynx ; Substance P ; Calcitonin generelated peptide ; Immunohistochemistry ; Vagotomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The distribution of substance P (SP) — and calcitonin gene-related peptide (CGRP) — containing nerve fibers in the rat larynx was studied using immunohistochemistry. Double-labeling studies revealed a high degree of co-existence of SP- and CGRP-like immunoreactivity (LI) in the nerve fibers in the larynx. There was a considerable regional difference in the number of immunoreactive nerve fibers in the epithelium and lamina propria. Richly supplied sites were the laryngeal side of the epiglottis and the ventral recess, whilst there was no evidence of nerve fibers in the squamous epithelium of the vocal cords. However, where the squamous epithelium of the vocal cords changed into a cuboidal epithelium, a moderate number of nerve fibers was present, and a large number of fibers was seen where the squamous epithelium of the cords was in close contact with cartilage. Nerve fibers showing SP- and CGRP-LI were also observed close to the acini and ducts of the glands, in the blood vessel walls, close to the perichondrium of all the cartilages, and outside the cricothyroid and cricoarytenoid joints. CGRP-LI was detected in epithelial cells facing the lumen of the airway and in cells in the acini and ducts of glands in the subglottic region and trachea. Unilateral sympathectomy did not affect the pattern of SP- and CGRP-innervation in the larynx, whereas after vagotomy, the SP- and CGRP-innervation almost disappeared ipsilaterally in the upper parts of the epiglottis and aryepiglottic folds.
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  • 112
    ISSN: 1432-0568
    Keywords: Mouse ; Neurological mutant ; Development ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The immunoreactivity in OZ42, a neural cell specific antibody that recognizes premigratory cerebellar granule cells, was examined in early postnatal wild-type and weaver mouse cerebella. We find that the OZ42-positive staining in the external granular layer (EGL) is first seen at postnatal day 1 in the most posterior and ventral aspect of midline cerebellum in the wild-type and heterozygous weaver mouse. By postnatal day 4 strong immunoreactivity is observed in the EGL of all cerebellar lobules. This staining is localized to a band of immunoreactive cells present at the interface of the EGL and the molecular layer (ML). In the homozygous weaver cerebellum, OZ42-positive staining is not seen until post-natal day 3. In the postnatal day 4 weaver cerebellum, immunoreactivity is considerably ligther than in littermate control cerebella, and found throughout the width of the EGL (i.e., not localized to the EGL-ML interface). This study demonstrates that the expression of a specific marker of granule cell development is abnormal in the granule cell population of the homozygous weaver mouse, a population of cells known to be intrinsically affected by the action of this mutant gene. In the light of previous studies, which have shown that the weaver phenotype is identifiable as early as the day of birth, and that the OZ42-antigen may be involved with the development process of axonal growth, it is reasonable to suggest that the weaver mutation results in an abnormality in the ability of granule cells to produce and/or stabilize axons.
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  • 113
    ISSN: 1432-0568
    Keywords: Endothelin ; Human ; Tooth pulp ; Tooth germ ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The distribution in oral tissues of endothelin, a multifunctional peptide originally identified within endothelial cells, and subsequently in some epithelial cells, neurons and neuroendocrine cells, has not been investigated yet. We have studied the localization of endothelin-like immunoreactivity in human tooth germ and mature dental pulp by immunohistochemical techniques. Such immunoreactivity was detected only within endothelial cells in both mature dental pulp and developing tooth. Arteries and veins of various sizes as well as small thin vessels displayed endothelin-like immunoreactivity. In the tooth germ, the cells of the enamel organ or the precursors of the odontoblasts were found unreactive. In the mature pulp, no cells of the stroma or nerves displayed endothelin-like immunoreactivity. These findings suggest that vascular endothelium may be the only source of endothelin in human dental tissues. It is tentatively proposed that endothelin released in mature tooth pulp may participate in the regulation of the pulpal blood flow. Although the possible role of endothelin in developing tissues is far from being clear, the mitogenic effects and the proto-oncogenes expression induced by endothelin in some cells raise the possibility that this peptide might also play a role during tooth development.
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  • 114
    ISSN: 1432-0533
    Keywords: Ethylnitrosourea-induced neurinomas ; RN6 neurinoma cell line ; Transplantation tumors ; Immunohistochemistry ; Intermediate filaments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The expression of glial fibrillary acidic protein (GFAP), vimentin, S-100 protein (S-100), HNK-1, myelin basic protein (MBP) and fibronectin was investigated immunohistochemically in 51 ethylnitrosourea (ENU)-induced neurinomas of the rat. Additionally, 90 transplantation tumors derived from ENU-induced neurinomas and the RN6 rat neurinoma cell clone were studied. Vimentin immunoreactivity was shown in 50/51 primary neurinomas and 60/90 transplantation tumors. In contrast, GFAP was expressed in only 23/51 primary tumors and in 5/90 transplantation tumors. In the RN6 neurinoma clone, vimentin and GFAP could be demonstrated both in vivo and in vitro GFAP expression varied depending on the tumor localization, i.e., tumors of distal portions of peripheral nerves were more frequently GFAP positive than tumors of the spinal roots or of cranial nerves. The same tendency was observed for S-100. In the series of transplantation tumors S-100 and GFAP immunoreactivity decreased with increasing numbers of transplantation passages. Only individual cells in 5 primary tumors were HNK-1 positive and no MBP-immunorcactive cells were observed. Our results demonstrate that the expression of differentiation antigens in ENU-induced experimental neurinomas parallels the results reported for human neurinomas.
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  • 115
    Electronic Resource
    Electronic Resource
    Springer
    Acta neuropathologica 82 (1991), S. 112-117 
    ISSN: 1432-0533
    Keywords: Rat brain tumors ; Granular cell tumors ; Immunohistochemistry ; Astrocytoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have studied paraffin-embedded specimens of 17 rat granular cell brain tumors (GCBT) from four long-term drug safety carcinogenicity studies by peroxidase-antiperoxidase (PAP) immunohistochemistry with either polyvalent or monoclonal antibodies against glial fibrillary acidic protein (GFAP), S-100 protein (S-100), Leu-7 epitopes, vimentin (VIM), keratin, desmin, and myelin basic protein. We have found that 9 of the 17 GCBT contained GFAP-positive, S-100-positive, and VIM-positive astrocytes, while GFAP-positive and VIM-positive granular cells were observed in 5 of these 9 tumors. Our findings indicate that astroglial cells are involved in rat GCBT and suggest that an astrocytic origin should be considered for these neoplasms.
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  • 116
    ISSN: 1432-0533
    Keywords: Gerbil ; Cerebral ischemia ; Vasogenic brain edema ; Immunohistochemistry ; Albumin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We investigated the temporal profile of the extravasation of serum albumin in a reproducible gerbil model of unilateral cerebral ischemia, using immunohistochemical and dye-tracer techniques to evaluate albumin accumulation and the occurrence of active extravasation, respectively. After 30 min of cerebral ischemia and subsequent reperfusion, immunostaining for albumin became visible in the lateral part of the thalamus during the first 3 h, and then expanded to other brain regions up to 24 h. At both 24 h and 3 days after reperfusion, massive extravasation of albumin was noted in the whole ischemic hemisphere, and this had decreased again by 7 days after reperfusion. The extent and the degree of albumin immunopositivity were almost the same in all animals examined at each period after reperfusion. The extravasation of Evans blue, which was allowed to circulate for 30 min before death, was limited to the lateral part of the thalamus during the first 6 h of reperfusion. In the circumscribed area of massive albumin extravasation, many neurons were immunopositive for albumin; most of these neurons appeared to be intact and also showed immunostaining for microtubule-associated protein 2. The current investigation clearly demonstrated that (1) albumin extravasation was produced with reliable reproducibility in this model, (2) the lateral part of the thalamus was the region most vulnerable to ischemic blood-brain barrier damage, and (3) many apparently intact neurons in the ischemic region were positive for albumin.
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  • 117
    ISSN: 1432-0533
    Keywords: Infratentorial ependymomas ; Childhood ; Immunohistochemistry ; AgNORs ; Prognosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have examined pathological criteria in 16 cases of infratentorial ependymomas of childhood using a conventional histological approach, with immunohistochemistry and silver nucleolar organizer region staining (AgNORs). We have found that some of these criteria are of prognostic value. The following histological features were evaluated in each case: cellular density, cellular or nuclear pleiomorphism, mitosis, focal necrosis, endothelial proliferation and complete loss of differentiation. The expression of the following antigens was also studied: epithelial membrane antigen (EMA), human natural killer (HNK1), glial fibrillary acidic protein (GFAP) and vimentin. Only three histological criteria have been retained as indicative of bad prognosis, i.e., high mitotic index, a large amount of necrosis and complete loss of differentiation. These criteria distinguish ependymomas from anaplastic ependymomas. GFAP was expressed in all tumors while other antigens were more variable. In addition tumors expressing large amounts of GFAP were statistically associated with a better prognosis. Increased vimentin expression associated with a decrease of GFAP immunoreactivity correlated with anaplasia and short survival. EMA was not directly correlated with postoperative survival but may be considered as a further prognostic factor. Finally AgNORs values were not statistically correlated with postoperative survival.
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  • 118
    Electronic Resource
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    Acta neuropathologica 82 (1991), S. 260-265 
    ISSN: 1432-0533
    Keywords: Immunohistochemistry ; Gerstmann-Sträussler syndrome ; Alzheimer's disease ; Kuru plaque ; Senile plaque
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We investigated paraffin-embedded brain sections from three patients with Gerstmann-Sträussler syndrome and three patients with Alzheimer's disease or senile dementia of Alzheimer type using anti-human prion protein antisera and anti-β/A4 protein antisera after protein denaturation treatments. After incubation with guanidine-thiocyanate, trichloroacetate, and phenol, the immunoreactivity of kuru plaques and senile plaques was enhanced to the same level as the formic acid treatment. These treatments revealed small compact amyloid deposits, amyloid deposits surrounding the plaque cores, and diffuse plaques. Most of these chemicals changed the congophilia of both amyloids. It is possible that these treatments denature amyloid fibril proteins and break down the structure of amyloid fibrils, thus revealing buried epitopes.
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  • 119
    ISSN: 1432-0533
    Keywords: Primitive neuroectodermal tumors (PNET) ; Cellular differentiation ; Immunohistochemistry ; Synaptophysin ; Chromogranin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Thirty-five selected intracranial tumors qualifying as primitive neuroectodermal tumors (PNETs) were investigated; these included medulloblastomas, cerebral neuroblastomas, pinealoblastomas, retinoblastomas, polar spongioblastomas, ependymoblastomas. For control purposes 11 tumors, including glioblastomas (small cell, spongioblastic variant), one anaplastic astrocytoma (astroblastic component), anaplastic oligoastrocytomas, gangliogliomas, one primary melanoblastoma, and one pineal germinoma, were also studied. Six neuronal markers, i.e., synaptophysin, chromogranin A, neuron-specific enolase (NSE), neurofilament protein (NFP) (160 kDa, 200 kDa, 70 and 200 kDa), and six other markers (glial fibrillary acidic protein, S-100 protein, vimentin, myoglobin, desmin, cytokeratin) were investigated immunohistochemically. A certain recapitulation of the ontogenetic development of neuronal differentiation in PNETs is given by the fact that chromogranin A immunoreactivity can regularly be seen already in poorly differentiated neurons and synaptophysin in well-differentiated ones. Immunostaining for NFPs showed different results depending on the subunit investigated. NSE reactions gave different results even within the single tumor groups. This study is, to the best of our knowledge, the first attempt to evaluate and compare, by combined morphological and immunohistochemical methods, PNETs without and with different stages of cellular differentiation with the stepwise differentiation of the human embryonic neuroectoderm.
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  • 120
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    Acta neuropathologica 82 (1991), S. 516-519 
    ISSN: 1432-0533
    Keywords: Multidrug resistance ; P-glycoprotein ; Glial tumor ; Immunohistochemistry ; RNA analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The most consistantly reported alteration of multidrug-resistant carcinoma cells is the overexpression of a membrane glycoprotein, termed P-glycoprotein. In this study we examined whether the strong intrinsic chemotherapy resistance of glial tumors might be related to the expression of the MDR1 gene which codes for P-glycoprotein. Fourteen glial tumors were examined immunohistochemically using the monoclonal antibody C219. In addition, RNA samples of 11 of these tumors were analysed using a sensitive Northern blot assay. P-glycoprotein is expressed in all 14 glial tumors; the number of stained tumor cells, however, varied considerably ranging from 0.3% to 15%. There was no correlation between the number of MDR1-positive cells and the histological malignancy. Varying amounts of MDR1 mRNA were detectable in 7 from 11 examined tumors. The results of our study show that the MDR1 gene is expressed in human glial tumors and suggest that the multidrug transporter may contribute to the clinical non-responsiveness of these tumors to chemotherapy.
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  • 121
    ISSN: 1432-0533
    Keywords: Early human CNS development ; Immunohistochemistry ; Synaptophysin ; Chromogranin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Aim of the present study was to establish different immunohistochemical staining patterns for a subsequent comparison with those of primitive neuroectodermal tumor (PNET) subsets, i.e. PNET-NOS (not otherwise specified) or PNET with focal neuronal, astrocytic or ependymal differentiation, to relate neoplastic to embryonal development. Tissue of the developing central nervous system, with special emphasis on the stepwise development of the rhombencephalon, the cerebellar and the retinal anlage, from 20 different human embryos and fetuses ranging from 3 to 30 weeks of gestational age (GA) was examined. Six neuronal markers, synaptophysin, chromogranin A, neuron-specific enolase (NSE), neurofilament protein (NFP; 160 kDa, 200 kDa, 70 and 200 kDa) and six other markers, glial fibrillary acidic protein (GFAP), S-100 protein, vimentin, myoglobin, desmin, cytokeratin, were assessed immunohistochemically. GFAP and S-100 protein appeared at the 6th week of GA in primitive glial cells of the cerebellar anlage, brain stem, rhombencephalon, and developing spinal cord, together with-as first neuronal marker-chromogranin A, then NFP (70 and 200 kDa, and 160 kDa) from the 8th week onward. NSE started in the 11th week and synaptophysin not earlier than the 16th week of GA. Interestingly, the differentiation of the retinal anlage started rather late with NSE positivity beginning from the 16th week and positive reactions to synaptophysin and NFPs only from the 25th and chromogranin A from the 28th week of GA onward.
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  • 122
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    Acta neuropathologica 81 (1991), S. 242-247 
    ISSN: 1432-0533
    Keywords: Senile plaque ; Microglia ; β Protein ; Immunohistochemistry ; Alzheimer's disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To clarify the association of microglia with senile plaques, the brains from 13 patients with Alzheimer's disease (AD) and 23 nondemented aged controls were investigated immunohistochemically by a double-labeling method using anti-β-protein antiserum and anti-ferritin antibody, which is a recently reported microglia marker. In addition, a quantitative analysis was performed. The senile plaques which appeared initially in the nondemented aged controls consisted of a diffuse type without any amyloid cores and these were found in the group aged 50–59 years. The great majority of them were found to contain no ferritin-positive microglia. The number and proportion (percentage) of microglia-containing diffuse plaques increased with age. Classical and compact plaques began to appear in the brains of the group aged 70 years and over, and practically all of them contained microglia. These results suggest that microglia are not associated with initial plaque formation, but correlate with amyloid core formation. In AD, the most prominent feature was that the diffuse plaques, which contained either no or only a few ferritin-positive microglia, increased markedly.
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  • 123
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    Acta neuropathologica 81 (1991), S. 401-407 
    ISSN: 1432-0533
    Keywords: Leukotriene C4 ; Basilar artery ; Neutrophils ; Macrophages ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experimental cerebral vasospasm was produced in a “two-hemorrhage” canine model and examined by immunohistochemistry for leukotriene C4 (LTC4). The immunostain for LTC4 showed a strong positivity in intima and adventitia and a scattered reaction in media of normal basilar artery. The immunoreactivity after subarachnoid hemorrhage (SAH) was little changed in intima and media. Inflammatory cells which were characterized histochemically as neutrophils and macrophages, were shown to infiltrate from the adventitia of basilar artery to the periphery of blood clot after SAH and were markedly immunoreactive for LTC4. Also the neutrophils increased in number with the lapse of time after SAH. Thus, it would be reasonable to conclude that the LTC4 responsible for the development of vasospasm would most likely be produced from the infiltrating neutrophils and macrophages. In addition, neurons in hypothalamus, median eminence, and pons, as well as ependymal and arachnoid cells were immunoreactive for LTC4 both in the control and after SAH, whereas astrocytes and oligodendrocytes were not immunoreactive for LTC4 in either case.
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  • 124
    ISSN: 1432-0533
    Keywords: Brain tumor ; S-100 protein ; Subunit ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The immunohistochemical distribution of α and β subunits of S-100 protein (S-100α, S-100β, respectively) in 138 cases of human brain tumors was investigated by the avidin-biotin immunoperoxidase method. Brain tumors can be divided into four groups: group 1 [S-100α (+) and/or S-100β (+)]; astrocytoma, glioblastoma, ependymoma, subependymoma, oligodendroglioma, choroid plexus papilloma, gangliocytoma, meningioma, chordoma, malignant melanoma. Group 2 [S-100α (+) and S-100β (-)]; pineoblastoma, pituitary adenoma, craniopharyngioma, rhabdomyosarcoma. Group 3 [S-100α (-) and S-100β (+)]; acoustic Schwannoma. Group 4 [S-100α (-) and S-100β (-)]; medulloblastoma, malignant lymphoma, germinoma. The S-100β immunoreactivity pattern in brain tumors was similar to those obtained using conventional anti-S-100 protein sera. In the first group of brain tumors both the number of positively stained tumor cells and the staining intensity were generally greater for S-100β than for S-100α with a few exceptions including one gemistocytic astrocytoma, one subependymoma, one malignant melanoma, and some cases of glioblastomas. As to the relationship between malignancy and S-100 protein in glioma, S-100β immunoreactivity decreased according to degree of malignancy, while that of S-100α varied, suggesting a heterogeneity of tumor cells in glioblastomas. Immunostaining for S-100α and S-100β might become a useful diagnostic procedure in brain tumors and may give us more detailed and precise data of S-100 protein in brain tumors.
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  • 125
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    Archives of dermatological research 283 (1991), S. 519-523 
    ISSN: 1432-069X
    Keywords: Psoriasis ; Epidermis ; Dermis ; Nerve fibres ; PGP 9.5 ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary There is conflicting evidence in the literature as to whether cutaneous nerves are altered in psoriasis or not. In this study, antibodies to protein gene product (PGP) 9.5 were used to visualize cutaneous nerves in biopsies from involved and uninvolved skin of nine patients with psoriasis and from normal skin of eight healthy controls. A profound reduction in the epidermal nerve fibre density was observed in the involved psoriatic skin. These intraepidermal nerve fibres were also mostly short and found in the basal layer. Only a few nerve fibres were found in the suprabasal layer and they were non-varicose, long fibres going straight up without branching. In the uninvolved skin of psoriatic patients, the distribution and number of the intraepidermal nerve fibres was similar to that observed in normal skin. In the dermis, the distribution and the number of the nerve fibres showed no differences between involved psoriatic skin, uninvolved psoriatic skin, and normal skin. The results support previous studies in which alterations of cutaneous nerves in psoriasis have been described.
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  • 126
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    Archives of dermatological research 283 (1991), S. 10-12 
    ISSN: 1432-069X
    Keywords: Neuron-specific enolase ; Langerhans cells ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 127
    ISSN: 1432-1106
    Keywords: Thalamus ; Intralaminar nuclei ; GABA ; Inhibition ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Immunohistochemistry using antibodies to glutamic acid decarboxylase (GAD) was used to investigate the intralaminar nuclei of the thalamus in rat, cat and monkey. Antibodies to gamma aminobutyric acid (GABA) were also used in the cat. Intralaminar immunoreactive cell bodies were not detected in the rat, but were clearly present in cat and monkey. In the latter species, GABA- or GAD-immunopositive perikarya were distributed throughout the anterior intralaminar nuclei, whereas in the posterior intralaminar complex they prevailed in the lateral part of the centre median nucleus and around the fasciculus retrofiexus. Measurements of the area of immunostained intralaminar cell bodies in cat and monkey indicated that they are represented by small neurons. Experiments in the cat, based on retrograde tracers injections involving large sectors of the frontal and parietal cortices and the head of the caudate nucleus, revealed that the GABA- or GAD-immunoreactive cells and the retrogradely labeled projection neurons represented two separate intralaminar cell populations, although the latter also included small cells. Considerable differences were observed in the immunoreactive GABAergic neuropil of the anterior and posterior intralaminar nuclei. Clusters of densely packed bouton-like immunoreactive elements were detected in the former structures in the rat, cat and monkey, and were especially evident in the central lateral nucleus; immunopositive varicose fibers and puncta were diffusely distributed in the posterior intralaminar structures. Taken together with data from the literature, the present findings indicate that in cat and monkey local circuit inhibitory cells regulate not only the activity of principal thalamic nuclei which project densely upon restricted cortical fields, but also of the intralaminar structures which are widely connected with the cerebral cortex and the striatum. Regional variations in the distribution of GABAergic fibers and terminals suggest major differences in the organization of inhibitory circuits and synaptic arrangements of the anterior and posterior intralaminar thalamus.
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  • 128
    ISSN: 1432-1106
    Keywords: Hypothalamic paraventricular nucleus ; PHA-L ; Spinal projection ; Sympathetic preganglionic neurons ; Dendritic organization ; Cholera toxin ; Immunohistochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The descending projection of the hypothalamic paraventricular nucleus (PVN) to the sympathetic preganglionic neurons (SPNs) in the upper thoracic cord of the rat was studied. PVN-fibers were labeled by anterograde transport of Phaseolus vulgaris leucoagglutinin (PHA-L), while SPNs were retrogradely labeled with cholera toxin subunit B (CTb) which was injected into the superior cervical ganglion. SPNs labeled with CTb were mainly observed in the nucleus intermediolateralis (IML) pars principalis and pars funicularis, and a small number of them were in the nucleus intercalatus (IC) and central autonomic nucleus (CA). SPNs found in the IML had dendrites that projected in various directions. Five types of dendritic projections were noted: medial, rostral, caudal, lateral (including dorsolateral) and ventral. Longitudinal dendritic bundles interconnected each cell cluster in the IML. Medial dendrites of the IML, together with dendrites of the IC and CA, formed transverse dendritic bundles extending from the IML to the central canal. The transverse dendritic bundles disentangled near the midline and formed a loose dendritic plexus in the region just dorsal to the central canal. PVN-fibers labeled with PHA-L were observed primarily in lamina I and intermediate gray (lamina VII). Although varicose PVN-fibers and SPNs coexisted in the IML, the tight packing of the dendritic bundles prevented any clear demonstration of direct contacts between them. On the other hand, PVN-fibers were occasionally found to appose and wind around the primary or secondary dendrites of some SPNs of the CA and IC. These dendrites were studded with varicosities of PVN-fibers for a short length, and terminal boutons of PVN-fibers were also seen to make contact directly with the dendrites. The results of this study substantiated a direct connection between the PVN and SPNs, using a combination of immunohistochemical techniques for PHA-L and CTb. The possible involvement of a direct pathway from the PVN to SPNs in cardiovascular regulation is discussed.
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  • 129
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    Experimental brain research 86 (1991), S. 90-96 
    ISSN: 1432-1106
    Keywords: Development ; Immunohistochemistry ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Previous results from our laboratory (Bejar et al. 1985) indicated that a single injection in mouse pups of the antimitotic/mutagenic agent methylazoxymethanol at postnatal day 5 typically produces hypogranular cerebella with no changes in foliation, in contrast to the severe alterations observed after the more usual injection on the day of birth. Here we report that injection of a higher dose (30 mg/kg) of methylazoxymethanol, always at postnatal day 5, leads to the additional presence of a ectopic cell layer in adult cerebellum. Immunostaining with several antibodies recognizing cell specific proteins ruled out the possibility that these ectopic cells were glial and electron microscopy indicated that they were morphologically mature granule cells. In the molecular layer of other cerebellar areas and apparently unrelated with granule cell ectopia, ectopic Golgi epithelial cells were observed. The reason for the presence of these ectopic cells of different type in the molecular layer was discussed in relation with analogous ectopias obtained by other means.
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  • 130
    ISSN: 1432-1106
    Keywords: Sympathetic preganglionic neurons ; Monoaminergic terminals ; Dendritic organization ; Cholera toxin ; Immunohistochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A ladder-like pattern of distribution of sympathetic preganglionic neurons (SPNs) was compared with that of monoaminergic terminals in the upper thoracic spinal cord of the rat. SPNs were identified by a retrograde labeling with cholera toxin subunit B (CTb) injected into the superior cervical ganglia of both sides. Monoaminergic terminals were stained immunohistochemically by using antisera raised against 5-hydroxy-tryptamine (5-HT) or dopamine- β -hydroxylase (DBH). SPNs showing full dendritic arbors were found in all of the sympathetic preganglionic nuclei. They formed a ladder in the horizontal plane. The nucleus intermediolateralis was connected with the central autonomic nucleus by many transverse dendritic bundles. Photomontages of serial sections of material stained alternatively with antisera against CTb and 5-HT or DBH clearly showed a close correlation between SPNs and monoaminergic terminals. There is no transverse dendritic bundle of SPNs without the accompaniment of monoaminergic terminals.
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  • 131
    ISSN: 1432-1254
    Keywords: Temporal variation ; Cytochrome P-450 isozyme ; Testis ; Immunohistochemistry ; Cadinenes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Abstract Temporal variations in cytochrome P-450 isozymes of rat testis, PB-P-450 (forms of cytochrome P-450 strongly induced by phenobarbital) and MC-P-448 (forms of cytochrome P-450 strongly induced by 3-methylcholanthrene), were investigated immunohistochemically by the avidin-biotin-complex method using specific antibodies against PB-P-450 and MC-P-448 isozymes. Immunoreactivity to both PB-P-450 and MC-P-448 isozymes was observed in Leydig cells. The number of PB-P-450 positive Leydig cells was found to undergo significant time-of-day variation with a peak time of 0000 hours (light phase from 0800 to 2000 hours). Injection of cadinenes (300 mg/kg per day intraperitoneally at 48 and 96 h before sacrifice) induced PB-P-450 isozyme but did not induce MC-P-448 isozyme. The induction of PB-P-450 isozyme by cadinenes was time dependent, and the early dark phase (2000 and 0000 hours) was most sensitive. These results suggest that temporal variation of cytochrome P-450 isozymes is one of the important physiological variations in detoxification and activation of various xenobiotics and chemicals in the testis.
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  • 132
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    Archives of gynecology and obstetrics 249 (1991), S. 173-177 
    ISSN: 1432-0711
    Keywords: Immunohistochemistry ; Granulosa cell tumors ; Ovarian carcinoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Differential diagnosis is a major problem in histopathology of ovarian tumors. Difficulties may arise if the tumor is a poorly differentiated carcinoma or a granulosa cell tumor of the sarcomatoid type. It was the aim of the present study to evaluate the usefulness of immunohistochemistry in differentiating between granulosa cell tumors of the ovary and ovarian carcinomas. We investigated 56 ovarian malignancies (13 granulosa cell tumors, 17 serous, 14 mucinous and 12 poorly differentiated carcinomas) and performed immunohistochemical detection of Vimentin, Keratin, CA125, CA19-9, CEA, S100 and Ber-EP4. Expression of Vimentin was highest and expression of Keratin was lowest in granulosa cell tumors in contrast to carcinomas. CA125 and CA19-9 were not expressed in granulosa cell tumors, whereas the detection rate in carcinomas (except for CA125 in mucinous carcinomas) was high. CEA, S100 and Ber-EP4 do not seem to be useful markers in differential diagnosis. A marker profile of Vimentin, Keratin, CA125 and CA19-9 allows a quite strict differentiation between poorly differentiated ovarian carcinomas and granulosa cell tumors of the ovary.
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  • 133
    ISSN: 1432-0738
    Keywords: Toxicopathology ; Immunohistochemistry ; Cell cycle analysis ; In situ hybridization ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Macroscopic and histologic evaluation of animal studies for general toxicity and carcinogenicity are cornerstones of the risk assessment of new chemical entities. Standard toxicopathologic evaluation is mainly based on the study of paraffin sections stained with hematoxylin and eosin. There are, however, a number of new approaches and techniques which have improved the objectivity of evaluation and the accuracy of cell identification, and provided deeper insight into the molecular biological mechanisms of toxicity and carcinogenicity. Such approaches include the standardization of the nomenclature, the creation of data banks for morphological alterations, the use of computers to register pathological findings in toxicity studies and to statistically evaluate incidences, and the use of morphometry. Other modern techniques are immunohistochemistry, in situ hybridization, and the assessment of cell kinetics.
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  • 134
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    Journal of cancer research and clinical oncology 117 (1991), S. 608-614 
    ISSN: 1432-1335
    Keywords: Prostatic cancer ; Radiotherapy ; Prognosis ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In a retrospective study, the extent of reactions of different types of prostatic carcinomas to external or interstitial radiotherapy was compared with reactions to hormonal therapy. It is shown that prostatic carcinomas of different grades of differentiation can be divided into two main subgroups with distinctly different survival rates; i.e., prostatic carcinomas grades of malignancy Ib/ IIa and grades IIb/III. Within an observation time of 10 years, the prostatic carcinoma grade of malignancy Ib/ IIa shows a good response to external and interstitial radiotherapy. None of the patients died of the prostatic carcinoma. In the more poorly differentiated prostatic carcinomas, 2 out of 11 patients with external radiotherapy died of the carcinoma. The death rates from disease after hormonal therapy were higher, and the survival times were very short without therapy. Regressive changes are much more distinctly expressed in the better-differentiated carcinoma group. Differential diagnostic difficulties between regressive changes in carcinomatous glands and normal glands could be resolved by immunohistochemical proof of high-molecular-mass cytokeratin in basal cells.
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  • 135
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    Child's nervous system 7 (1991), S. 109-111 
    ISSN: 1433-0350
    Keywords: Malignant choroid plexus papilloma ; IV Ventricle ; Cerebellopontine angle extension ; Fibrous encapsulation ; Immunohistochemistry ; Epithelial membrane antigen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report a case of malignant choroid plexus papilloma (MCPP) of the IV ventricle in a child with prominent extraventricular expansive growth, mostly into the cerebellopontine angle. Interestingly enough, the tumor was entirely covered by thin, smooth, membranous, fibrous tissue, probably derived from the pia mater. In addition, hydrocephalus was not observed. The reason for the lack of hydrocephalus remains speculative, but it is possible that the presence of pure, nonexpansive, fibrous covering on the tumor might have suppressed the tumor growth to some extent, resulting in progressively increased intratumoral pressure. This, in turn, caused the suppression of excessive cerebrospinal fluid production by the tumor cells. From the diagnostic standpoint, immunohistochemical studies, using antiepithelial membrane antigen (EMA) and antitissue polypeptide antigen (TPA), were demonstrated to be useful for diagnosing the tumor.
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  • 136
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    Child's nervous system 7 (1991), S. 437-441 
    ISSN: 1433-0350
    Keywords: Choroid plexus tumor ; Immunohistochemistry ; Childhood
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Choroid plexus tumors are rare and account for only 2.3% (8/352) of primary childhood intracranial neoplasms in our series. Most of our patients were under 2 years of age. The tumors had a predilection for the lateral ventricle. Calcification was found in half of these tumors, and ossification was seen in 1 case. Histological features of malignancy including invasion, loss of differentiation, and severe nuclear pleomorphism pointed to a poor prognosis. Such features were found in 2 cases. Neither a large number of mitoses nor necrosis was a constant feature in cases of malignancy. Transthyretin, a marker for choroid plexus tumors, was positive in all cases. However, negative S-100 or positive carcinoembryonic antigen was not necessarily associated with a more aggressive histological pattern. All the papillomas could be totally resected without recurrence, and all the patients with carcinoma died within a few months.
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  • 137
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    Journal of neurology 238 (1991), S. 320-322 
    ISSN: 1432-1459
    Keywords: Parvalbumin ; Calcium-binding protein ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The cellular distribution of parvalbumin-like immunoreactivity (PA-LI) in the human brain was investigated by peroxidase-antiperoxidase methods using antiserum to rat skeletal muscle parvalbumin. PA-LI was present in non-pyramidal neurons of the cerebral cortices, stellate cells, basket cells and Purkinje cells in cerebellar cortices, and neurons of some nuclei in human brain stem; the distribution of PA-LI in human brain was very similar to that in rat brain. These results indicate that PA-LI is widely distributed in a specific subpopulation of neurons of the human brain.
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    Journal of neurology 238 (1991), S. 200-202 
    ISSN: 1432-1459
    Keywords: Parvalbumin ; Immunohistochemistry ; Cerebral cortex ; Pick's disease ; Alzheimer-type dementia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Parvalbumin (a calcium-binding protein)-immunoreactive (PV-Ir) neurons in the cerebral cortex were examined in 20 postmortem brains obtained from elderly controls and patients with Pick's disease (PD). The type of PV-Ir neurons and their distribution in control and PD brains were similar. The number of PV-Ir neurons in PD brains did not differ significantly from that in the control brains either. These findings suggested that PV-Ir neurons in the cortex are not affected in PD brains. A significant loss of PV-Ir neurons has already been reported in brains obtained from patients with Alzheimer-type dementia (ATD), and the present results suggest the possibility that the damage of PV-Ir neurons might be comparatively selective for ATD brains.
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  • 139
    ISSN: 1432-1459
    Keywords: Becker muscular dystrophy ; Dystrophin ; Manifesting carrier ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Immunohistochemical localization of dystrophin was studied in a symptomatic carrier of Becker muscular dystrophy (BMD). Muscle biopsy specimens from a female carrier showed findings compatible with slowly progressive muscular dystrophy by ordinary histochemical examinations. Immunohistochemical study, using an antiserum raised against a synthetic peptide fragment of dystrophin, demonstrated a mixture of staining patterns, including continuous but faint positive fibres, partially disrupted fibres and negative fibres. These findings were identical to those of patients with BMD and appear to differ from previous findings in female carriers of Duchenne muscular dystrophy. This report is the first immunohistochemical study of a symptomatic female proven by molecular genetic analysis to be a carrier of BMD.
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  • 140
    ISSN: 1432-0878
    Keywords: Serotonin ; Pancreas ; Phylogenic study ; Immunohistochemistry ; Teleosts ; Chicken ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution pattern of serotonin (5HT) in the pancreas was studied immunohistochemically by using a 5HT monoclonal antibody in various vertebrates including the eel, bullfrog, South African clawed toad, turtle, chicken, mouse, rat, guinea-pig, cat, dog and human. In all species examined, except the bullfrog, 5HT-like immunoreactivity was observed in nerve fibers, in endocrine cells, or in both. Positive nerve fibers were found in the eel, turtle, mouse, rat and guinea-pig. These fibers ran mainly along the blood vessels and partly through the gap between the exocrine glands. In the eel and guinea-pig, positive fibers invaded the pancreatic islet. Occasionally, these positive fibers were found adjacent to the surface of both exocrine and endocrine cells, suggesting a regulatory role of 5HT in pancreatic function. 5HT-positive endocrine cells were observed in the pancreas of all species except for the bullfrog and rat. In the eel and in mammals such as the mouse, guinea-pig, cat, dog and human, 5HT-positive cells were mainly observed within the pancreatic islet. In the South African clawed toad, turtle and chicken, the positive cells were mainly in the exocrine region. The present study indicates that the distribution patterns of 5HT in the pancreas varies considerably among different species.
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  • 141
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    Cell & tissue research 263 (1991), S. 431-438 
    ISSN: 1432-0878
    Keywords: Connective tissue ; EHS tumor ; Basement membrane ; Amyloid P component ; Immunohistochemistry ; Mouse (C57BL/6)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A new minute connective tissue structure, referred to as “pentosome”, has been investigated by electron microscopy and its nature has been examined by immunoperoxidase tests. Pentosomes are 3.5-nm wide, particulate structures that have been observed in the posterior chamber of the eye, the connective tissue spaces of the mouse foot-pad and the matrix of the mouse EHS tumor. They are usually found in the vicinity of microfibrils whether they are free or associated with elastic fibers. They tend to be organized into groups forming a three-dimensional semi-crystalline lattice at 10-nm intervals, but are connected by fine filaments. At high magnification, pentosomes appear as hollow structures composed of two parallel pentagons, which respectively measure 2.7 and 3.5 nm, and are held together by a cross-bar. A series of immunoperoxidase tests has only shown antigenicity against a serum protein, the amyloid P component. However, pentosomes are only about one-third the size of the 8.5-nm wide, disk-like segments of the amyloid P molecule. Since they could be subunits of these molecules, such subunits were prepared and compared with pentosomes; they appeared to be identical. It is concluded that the pentosomes found in connective tissue are AP subunits.
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  • 142
    ISSN: 1432-0878
    Keywords: FMRFamide ; Catch-relaxing peptide (CARP) ; Radula muscle ; Immunohistochemistry ; Rapana thomasiana (Mollusca)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In a prosobranch mollusc, Rapana thomasiana, the catch-relaxing peptide H-Ala-Met-Pro-Met-Leu-Arg-Leu-NH2 (CARP) was found to depress the contraction of the radula protractor and retractor elicited by electrical stimulations. The action of CARP was in contrast to that of other neuropeptides, H-Phe-Met-Arg-Phe-NH2 (FMRFamide) and H-Phe-Leu-Arg-Phe-NH2 (FLRFamide), which enhanced the contraction of the radula protractor and retractor, respectively. By immunohistochemical examinations, FMRFamide-like immunoreactive neurons were found on the rostral side of the right buccal ganglion and the caudal side of the left ganglion, where some CARP-like immunoreactive neurons were also distributed, indicating a possible coexistence of FMRFamide and CARP. FMRFamide- and CARP-like immunoreactivities were also detected in the neuropile of buccal ganglia, radula nerves arising from the ganglia, and nerve fibers in the radula muscles. The present results suggest that FMRFamide- and CARP-like peptides are involved in the regulation of the contraction of the radula muscles.
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  • 143
    ISSN: 1432-0878
    Keywords: Calbindin ; Immunohistochemistry ; Teleosts ; Visual system ; Entreleation ; Cyprinus carpio ; Tinca tinca (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Using the ABC immunohistochemical method, we investigated the distribution of calbindinlike immunoreactive structures in the optic tectum of normal fish, Tinca tinca, and from normal and unilaterally eye-enucleated fish, Cyprinus carpio. In nonoperated individuals of both species the optic tectum contained numerous immunoreactive neurons with strongly positive somata located in the stratum periventriculare and a thick immunolabeled dendritic shaft ascending radially toward the stratum fibrosum et griseum superficiale. The retinorecipient layers contained many fibrous immunoreactive structures. Some varicose fibers, isolated or in small bundles, were localized to the stratum album centrale, especially in the dorsal tectal half. Unilateral eye removal produced the disappearance of the immunoreactive fibrous structures located in the retinorecipient layers of the tectum contralateral to the enucleation. The present work shows that calbindinlike immunoreactive substances are localized in specific neural circuits of the fish optic tectum and suggests that the calbindin-like immunoreactive fibers in the retinorecipient strata are of retinal origin.
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  • 144
    ISSN: 1432-0878
    Keywords: L2/HNK-1 carbohydrate epitope ; L3 carbohydrate epitope ; Immunohistochemistry ; Extracellular matrix ; Calliphora vicina (Insecta) ; Drosophila melanogaster (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The carbohydrate epitopes L2/HNK-1 and L3 belong to two overlapping families of adhesion molecules in the vertebrate, and probably the invertebrate nervous systems. To investigate their pattern of expression during the development of insects, cryosections of late third instar larvae and imagoes of Drosophila melanogaster and Calliphora vicina were studied by indirect immunofluorescence using several monoclonal antibodies to the L2/HNK-1 and one monoclonal antibody to the L3 epitope. Each monoclonal antibody to the L2/HNK-1 epitope showed a different immunohistological staining pattern, which differed from that of the L3 monoclonal antibody. In both insect species the immunohistological staining patterns for the two carbohydrate epitopes were similar at the two developmental stages, with immunoreactivity not confined to the nervous system. In larvae, immunoreactivities of the monoclonal antibodies L2.334 and L3.492 were predominantly associated with the extracellular matrix as indicated by co-localization with laminin, particularly in the imaginal discs, while L2.349 revealed a more cell surface-associated distribution. In imagoes, immunoreactivities were detectable in most organs studied.
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  • 145
    ISSN: 1432-0878
    Keywords: Calbindin ; Neurohypophysis ; Development, ontogenetic ; Immunohistochemistry ; In-situ hybridization ; Electron microscopy ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Spot 35 protein is a Ca-binding protein originating from the rat cerebellum; it is now referred to spot 35-calbindin. This protein is expressed in immature pituicytes of the neurohypophyseal anlage in the E11–E18 rat embryo. The gene expression of spot 35-calbindin was detected by in-situ hybridization analysis only at stage E11–E12. Profiles of spot 35-positive nerve fibers of a neurosecretory nature were found in anlage at stage E16. At this stage, some immature pituicytes are partially immunopositive for spot 35-calbindin only in their peripheral cytoplasm; others are immunonegative. At birth and thereafter through adulthood, abundant nerve fibers are the sole structures immunoreactive for spot 35-calbindin; all the pituicytes are immunonegative, resulting in a light-microscopic appearance of numerous immunonegative round profiles, corresponding to pituicytes, and capillaries embedded in the granularly immunostained neurohypophysis. The present findings suggest that, during specific embryonic stages, immature pituicytes exert some as yet unidentified roles related to Ca-mediated functions involving the expression of spot 35-calbindin.
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  • 146
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    Cell & tissue research 266 (1991), S. 391-398 
    ISSN: 1432-0878
    Keywords: Photoreceptor cells ; Nervous system central ; Visual system ; Histamine ; Transmitter ; Immunohistochemistry ; Drosophila melanogaster (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In this study, immunohistochemistry on cryostat sections is used to demonstrate anti-histamine immunoreactivity in the Drosophila brain. The results support earlier findings that histamine is probably a transmitter of insect photoreceptors. It is further shown that, in Drosophila, all imaginal photoreceptors including receptor type R7 are anti-histamine immunoreactive, whereas the larval photoreceptors do not seem to contain histamine. In addition to the photoreceptors, fibres in the antennal nerve and approximately 12 neurons in each brain hemisphere show strong histamine-like immunoreactivity. These cells arborize extensively in large parts of the central brain.
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  • 147
    ISSN: 1432-0878
    Keywords: Subcommissural organ ; Differentiation ; Transplantation ; Immunohistochemistry ; GFAP ; S100 protein ; Serotonin ; Rat (Sprague-Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The rat subcommissural organ (SCO), principally composed of modified ependymocytes (a type of glial cell), is a suitable model for the in vivo study of glial differentiation. An immunohistochemical study of the ontogenesis of rat SCO-ependymocytes from embryonic day 13 to postnatal day 10 shows that these cells express transitory glial fibrillary acidic protein (GFAP) from embryonic day 19 until postnatal day 3. However, S100 protein (S100) is never expressed in the SCO-cells, contrasting with the ventricle-lining cells of the third ventricle, which contain S100 as early as embryonic day 17. Environmental factors could be responsible for the repression of GFAP and S100 in adult rats, because GFAP and S100 are observed in ependymocytes of SCO 3 months after being grafted from newborn rat into the fourth ventricle of an adult rat. Neuronal factors might be involved in the control of the expression of S100, since after the destruction of serotonin innervation by neurotoxin at birth, S100 can be observed in some SCO-ependymocytes of adult rats. On the other hand, GFAP expression is apparently not affected by serotomin denervation, suggesting the existence of several factors involved in the differentiation of SCO-cells.
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  • 148
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    Cell & tissue research 263 (1991), S. 353-366 
    ISSN: 1432-0878
    Keywords: 3-Fucosyl-N-acetyl-lactosamine (FAL) ; Leu-M1 ; CD-15 marker ; Brain mapping ; Immunohistochemistry ; Mouse (NMRI)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of the 3-fucosyl-N-acetyl-lactosamine (FAL) epitope within the adult mouse brain was studied by immunohistochemistry using the monoclonal antibody Leu-M1. Leu-M1-positive elements comprised astrocytes and neurons. FAL-positive astrocytes were particularly abundant in barrier structures of the brain, but were also prominent at the periphery of most medullated fiber tracts. Their intracerebral distribution led to a distinct pattern of organization, which in some locations, including the cerebral cortex, could be used for an extended regional architectonic description. Since only some FAL-positive astrocytes were also positive for glial fibrillary acid protein (GFAP), the emerging topography of the FAL-positive astrocytes often differed from the GFAP-distribution. In the cerebellum, Bergmann glia cells expressed the FAL epitope and, in the vermis, their arrangement had a band-like appearance. Positive oligodendrocytes could not be identified. The common ependymal cells were negative, whereas tanycytes were highly immunoreactive. The Leu-M1 antibody also stained some neurons. These occurred in selected neocortical regions, within the dorsal and ventral striatum, in the globus pallidus, the nucleus basalis of Meynert, the nucleus diagonalis and some hypothalamic areas. In some instances, their morphology and location indicated an association with neurochemically specified cell groups.
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  • 149
    ISSN: 1432-0878
    Keywords: Diazepam-binding inhibitor (DBI) ; DBI-like immunoreactivity ; Pancreas, endocrine ; Immunohistochemistry ; Peptides ; Rat (Sprague-Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The occurrence of diazepam-binding inhibitor (DBI), isolated and characterized from porcine upper intestine, was examined in the pancreas of Sprague-Dawley albino rats using indirect immunofluorescence. The polypeptide was found in the endocrine Langerhans islets and, utilizing double-labelling controls, it was shown to be present within the peripherally located glucagon-containing cells. Regulation of islet hormone production may therefore be under DBI control.
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  • 150
    ISSN: 1432-0878
    Keywords: Chromogranin ; Secretogranin ; Enteroendocrine cells ; Immunohistochemistry ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The family of the chromogranin/secretogranin proteins consists of three major subtypes: chromogranin A (CgA), chromogranin B (CgB) and secretogranin II (SgII). These proteins are present in various endocrine cells and organs. Using immunohistochemistry on serial semithin sections, we have investigated ten endocrine cell types of the guinea pig gastro-intestinal tract for their content of chromogranin/secretogranin proteins. The gastrin cell was the only cell type containing immunoreactivities for all three chromogranin subtypes. The majority of entero-endocrine cells showed immunoreactivities for CgA and SgII. Somatostatin cells lacked immunoreactivities for any of the chromogranins. Moreover, the densities of the corresponding immunoreactivities varied among the different endocrine cell types or even among endocrine cells of a given population. Aminergic endocrine cells (e.g., enterochromaffin and enterochromaffin-like cells) regularly exhibited strong immunoreactivities for CgA but failed to react for SgII. In peptidergic endocrine cells, the immunoreactivities for both CgA and SgII ranged from dense to faint. This was also true for CgB in gastrin cells. Hence, only CgA and SgII can be considered as regular constituents of entero-endocrine cells. The intercellular differences in immunoreactivities for all three chromogranin subtypes indicate that every endocrine cell has its own composition of chromogranin/secretogranin proteins. This may be due to differences in the regulation of biosynthesis or processing of the chromogranins in individual endocrine cells; this in turn might be related to the functional states of endocrine cells.
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  • 151
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    Cell & tissue research 264 (1991), S. 461-467 
    ISSN: 1432-0878
    Keywords: Synaptophysin ; P38 ; Membrane proteins ; Endocrine pancreas ; Islet cells ; Immunohistochemistry ; Human ; Dog ; Gerbil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Synaptophysin, a major membrane glycoprotein of small presynaptic vesicles in neurons, has also been found in microvesicles of endocrine cells, e.g., of the endocrine pancreas. In the present study, the endocrine pancreas in 9 mammalian species (man, dog, mink, bovine, rabbit, guinea pig, rat, mouse, gerbil) has been investigated immunohistochemically for synaptophysin immunoreactivity. Synaptophysin-positive cells have been identified and localized on semithin plastic sections. Our study demonstrates that, in all species examined, all pancreatic endocrine cell types are consistently synaptophysin-positive independent of their location within the tissue, or the conditions of tissue processing. In addition, a few cells that cannot be hormonally identified show synaptophysin immunoreactivity. Hence, synaptophysin appears to be a regular constituent of all pancreatic endocrine cells in mammals. In several species, a subpopulation of endocrine cells, consisting of glucagon-containing and/or pancreatic-polypeptide-containing cells, exhibits a significantly higher degree of synaptophysin immunoreactivity. In the gerbil, this heterogeneity can readily be detected from the day of birth onwards. Our findings indicate that closely related endocrine cell types may differ with respect to the content of synaptophysin.
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  • 152
    ISSN: 1432-0878
    Keywords: Neuropeptide Y ; Tyrosine hydroxylase ; Extrasympathetic innervation ; Pineal gland ; Deep pineal ; Immunohistochemistry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of tyrosine hydroxylase (TH)- and neuropeptide Y (NPY)-immunoreactive(IR) nerve fibers in the pineal complex was investigated in untreated rats and rats following bilateral removal of the superior cervical ganglia. In normal animals, a large number of TH- and NPY-IR nerve fibers were present in the pineal capsule, the perivascular spaces, and intraparenchymally between the pinealocytes throughout the superficial pineal and deep pineal gland. A small number of TH-IR and NPY-IR nerve fibers were found in the posterior and habenular commissures, a few fibers penetrating from the commissures into the deep pineal gland. To elucidate the origin of these fibers, the superior cervical ganglion was removed bilaterally in 10 animals, and the pineal complex was examined immunohistochemically. Two weeks after the ganglionectomy, the TH-IR and NPY-IR nerve fibers in the superficial pineal gland had almost completely disappeared. On the other hand, in the deep pineal and the pineal stalk, the TH-IR and NPY-IR fibers were still present after ganglionectomy. These data show that the deep pineal gland and the pineal stalk possess an extrasympathetic innervation by TH-IR and NPY-IR fibers. It is suggested that the extrasympathetic TH-IR and NPY-IR nerve fibers innervating the deep pineal and the pineal stalk originate from the brain.
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  • 153
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    Cell & tissue research 265 (1991), S. 175-184 
    ISSN: 1432-0878
    Keywords: Nervous system ; Nervous system, peripheral ; Catecholamines ; Immunohistochemistry ; Glyoxylic acid fluorescence ; Ophryotrocha puerilis (Annelida)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The complex catecholaminergic (CA) nervous system of the polychaete Ophryotrocha puerilis is documented using glyoxylic acid induced fluorescence (GIF) and immunohistochemistry. CA-neurons are found both in the central and peripheral nervous system. In the brain, about 50 CA-neurons are present in the perikaryal layer together with numerous CA fibres. Two pairs of CA perikarya are characteristic for each ganglion of the ventral nerve cord. CA-neurites in the ventral nerve cord are mainly arranged in 4 strands paralleling the longitudinal axis of the worm. Fluorescent neurons with receptive ciliary structures are present in body appendages (antennae, palps, urites, parapodial cirri), in the body-wall, and within the oesophageal wall. Furthermore, a subepidermal nerve net of free CA nerve endings has been found. After incubation of specimens with dopamine prior to the development of GIF more fluorescent perikarya could be observed; the fluorescence was also intensified. Pre-incubation with reserpine reduced the intensity of GIF. Results of high pressure liquid chromatography and immunostaining with a polyclonal antibody against a dopamine-glutaraldehyde-complex suggest that dopamine is the major CA transmitter. It is thought that dopaminergic neurons together with ciliary receptive structures act as mechano- and/or chemoreceptors.
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  • 154
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    Cell & tissue research 265 (1991), S. 251-260 
    ISSN: 1432-0878
    Keywords: Endocrine pancreas ; Immunization ; Glucagon ; Somatostatin ; Immunohistochemistry ; Rabbit (Chinchilla, Ch:b:Ch)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Peptide antibodies raised in rabbits are widely used in biology and medicine. During immunization of the animals, the respective antibodies may affect the endocrine cells physiologically responsible for the synthesis of peptides used as antigens. Since corresponding morphological data are still sparse, the rabbit endocrine pancreas was systematically investigated by light microscopy and immunocytochemistry after long-term immunization against glucagon and somatostatin. Both immunizations led to an increase in the number of islets (nesidioblastosis), to the development of giant islets (macronesia), and to changes in the relative proportions of the major types of endocrine cells or their hormonal content. The latter changes differed after either immunization: glucagon immunization resulted in hypertrophy and hyperplasia of glucagon cells and a decrease in their hormonal content; somatostatin immunization led to an increased proportion of somatostatin cells and a lowered hormonal content of insulin cells. The various alterations were expressed differently according to islet type; islets of the rabbit pancreas differ in size or angioarchitecture, and in the proportion and distribution of endocrine cells. The present findings point to autocrine or paracrine effects of the respective peptides. These effects, however, are obviously of differing significance in morphologically heterogeneous islets.
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  • 155
    ISSN: 1432-0878
    Keywords: Parenteral feeding ; Gut-associated lymphoid tissue ; Peyer's patches ; Immunoglobulin A ; Immunohistochemistry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphological alteration of gut-associated lymphoid tissue (GALT) induced by long-term absence of dietary stimulation was investigated. Male Wistar rats weighing ∼230 g were maintained with total parenteral nutrition (TPN). Control rats were allowed to have the same amount of the solution orally. After two weeks, the morphological alteration of GALT was examined. Although no significant difference in weight gain was noted between the two groups, the area comprised by Peyer's patches was decreased in TPN rats. The number of transported lymphocytes and the ratio of helper T (Th) cells to suppressor/cytotoxic T (Ts/c) cells in intestinal lymph were lowered after TPN treatment. In an immunohistochemical study of the rat ileum, the number of T cells and the Th/Ts/c ratio were decreased both in the intraepithelial spaces and in the lamina propria of TPN rats. The percentage of interleukin-2 receptor-positive cells and the number of IgA-containing cells in the lamina propria were significantly reduced in TPN rats. These results suggest that dietary stimulation might play a role in the maintenance of GALT function and morphology.
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  • 156
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    Cell & tissue research 266 (1991), S. 107-116 
    ISSN: 1432-0878
    Keywords: Serotonin ; Immunohistochemistry ; CSF-contacting neurons ; Raphe ; Hagfish (Eptatretus burgeri)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunohistochemical techniques were used to study the distribution of serotonin in the central nervous system of the hagfish,Eptatretus burgeri, in order to produce a detailed map of serotonin-containing structures. In the hypothalamus, many serotonin-containing neurons contacted the cerebrospinal fluid. Most of the serotonin-containing cell bodies were located in the raphe region, where they were compactly distributed at the level of the nucleus motorius tegmenti pars anterior but more diffusely distributed at the level of the nucleus motorius tegmenti pars posterior. Serotonin-containing cell bodies and varicose fibers were widely distributed throughout the brain and upper spinal cord segments, but the distribution density was not even. On the basis of its abundance, serotonin can be judged to have an important function in the control of the hagfish central nervous system. From a phylogenetic point of view, serotonin-containing neurons in the raphe region appear to be a common property of all classes of vertebrates studied except the lampreys, whereas serotonin-containing cerebrospinal fluid-contacting neurons may be considered to be a primitive condition in all nonmammalian vertebrates.
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  • 157
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    Cell & tissue research 266 (1991), S. 173-190 
    ISSN: 1432-0878
    Keywords: Neuroanatomy ; Identified neurons ; Immunohistochemistry ; Suboesophageal ganglion ; Tenebrio molitor (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Topological organization of identified neurons has been characterized for the larval, pupal and imaginal suboeosphageal neuropil of the meal-worm beetleTenebrio molitor. Neuronal fate mapping allows identification of individually persisting neurons in the metamorphosing suboesophageal ganglion ofTenebrio. Analysis was performed on interneurons characterized by serotonin and CCAP (crustacean cardioactive peptide) immunohistochemistry, on motoneurons that innervate the dorsal and ventral longitudinal muscles, and on suboesophageal descending neurons. All these different populations of neurons show topologically invariant features throughout metamorphosis. Motoneurons, interneurons, and descending suboesophageal neurons of the imaginal suboeosphageal ganglion embody individually persisting larval interneurons. Impacts for a functional interpretation of the neuronal architecture of the suboesophageal ganglion are discussed.
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  • 158
    ISSN: 1432-0878
    Keywords: Hairy skin tissue fetal ; Transplantation ; Anterior eye chamber ; Immunohistochemistry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pieces of hairy skin tissue of fetal rat were transplanted into the anterior eye chamber of adult rats. The ability of autonomic and sensory nerve fibers from the host iris to innervate the grafted skin tissue was immunohistochemically and enzyme-histochemically examined using antisera against tyrosine hydroxylase (TH), substance P (SP), calcitonin gene-related peptide (CGRP) and vasoactive intestinal peptide (VIP), and a reaction medium for acetylcholinesterase (AchE). The grafted tissue was successfully implanted and connected with the host iris. Epidermis, dermis, subcutaneous tissue, hairs, hair follicles, sebaceous glands, and piloerector muscles developed in the graft. Two weeks after transplantation, TH-, SP-, and CGRP-immunoreactive fibers were observed in association with the blood vessels in the graft. Four weeks after transplantation, TH-immunoreactive fibers were distributed in the piloerector muscles, whereas SP-and CGRP-immunoreactive fibers were present around the hair follicles. VIP-immunoreactive and AchE-positive fibers were restricted to the host iris at all survival times. These results suggest that the outgrowth of autonomic and sensory nerve fibers from the host iris show target specificity for the grafted skin tissue.
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  • 159
    ISSN: 1432-0878
    Keywords: Oxytocin ; Mating ; Oxytocinergic systems ; Radioimmunoassay ; Immunohistochemistry ; Functional activation ; Mouse (Holtzman CD, C. River)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Sexual stimulation of males has been reported to affect hypothalamic oxytocinergic systems. In the present study we used radioimmunoassays of micro-dissected forebrain regions and immunocytochemical analysis of Vibratome sections to study the oxytocin systems of naive males, males killed after one mating, and males mated daily with different receptive females for 3 weeks. In males that had mated once, less oxytocin-immunoreactive neurons were observed in the paraventricular (PVN), supraoptic (SON) and periventricular (NPE) nuclei than in naive males. However, after repeated matings, the number of immunoreactive neurons and their staining intensity was increased in these regions. Furthermore, additional oxytocinergic neurons could be found in the lateral subcommissural nucleus, the zona incerta and the ansa lenticularis of repeatedly mated males. Oxytocin-immunoreactive neurons were only occasionally seen in these areas in unmated males or in animals that had been killed after initial mating. Radio-immunoassays of microdissected PVN, SON, NPE and the lateral hypothalamus confirmed the reduction in oxytocin-immunoreactive levels after a first mating by a male and the increase after repeated matings. It is likely that oxytocin secretion into peripheral and portal circulation is stimulated by the endocrine conditions associated with initial mating. These immediate effects may be followed by the activation of synthesis in oxytocin neurons in several sites of the basal forebrain.
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  • 160
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    Cell & tissue research 266 (1991), S. 507-510 
    ISSN: 1432-0878
    Keywords: Brush cells ; Billiary system ; Development, ontogenetic ; Immunohistochemistry ; Liver fatty-acid-binding protein ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The postnatal development of brush cells in the distal segment of the common bile duct of the rat was examined with respect to cell number and immuno-reactivity for liver fatty acid-binding protein (L-FABP). The brush cells, distinguishable from the principal cells by scanning electron microscopy, first appeared in the common bile duct 4 weeks after birth. They showed a remarkable increase in number, with a sex difference in time, i.e., between 8 and 12 weeks in the male and between 10 and 14 weeks in the female. In both sexes, the frequency of brush cells reached approximately 30% of total epithelial cells by 16 weeks and remained constant until 40 weeks of age. Cells with positive immuno-reactivity for L-FABP first appeared in small numbers at 8 weeks. Immuno-electron microscopy revealed that all immunoreactive cells were brush cells. They increased in number gradually from 16 to 40 weeks with no sex difference. At 40 weeks, the immunoreactive cells reached approximately 7.5% of total epithelial cells, corresponding to one-fourth of the number of brush cells. These results indicate that the occurrence of the brush cell population in the common bile duct is a late event in the postnatal development of the rat and that its functional maturation progresses with aging.
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  • 161
    ISSN: 1432-0878
    Keywords: Stomatogastric ganglion ; Interneuron ; Crustacea ; Histamine ; Immunohistochemistry ; Pacifastacus leniusculus (Crustacea) ; Homarus americanus (Crustacea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary We used a polyclonal antiserum against histamine to map histaminelike immunoreactivity (HLI) in whole mounts of the segmental ganglia and stomatogastric ganglion of crayfish and lobster. Carbodiimide fixation permitted both HRP-conjugated and FITC-conjugated secondary antibodies to be used effectively to visualize HLI in these whole mounts. Two interneurons that send axons through the inferior ventricular nerve (ivn) and the stomatogastric nerve to the stomatogastric ganglion had strong HLI, both in crayfish and in lobster. These ivn interneurons were known from other evidence to be histaminergic. The neuropil of the stomatogastric ganglion in both crayfish and lobster contained brightly labeled terminals of axons that entered the ganglion from the stomatogastric nerve. No neuronal cell bodies in this ganglion had HLI. Each segmental ganglion contained at least one pair of neurons with HLI. Some neurons in the subesophageal ganglion and in each thoracic ganglion labeled very brightly. Axons of projection interneurons with strong HLI occurred in the dorsal lateral tracts of each segmental ganglion, and sent branches to the lateral neuropils and tract neuropils of each ganglion. All the labeled neurons were interneurons; no HLI was observed in peripheral nerves.
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  • 162
    ISSN: 1432-0878
    Keywords: Reticulum cells ; Monoclonal antibodies ; Splenic white pulp ; Immunohistochemistry ; Mouse (C3H/He)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Monoclonal antibodies against cellular components of reticular meshworks were produced by immunizing rats with heterogeneous stromal-cell population of mouse spleen. Immunohistochemical screening selected two antibodies, WP-1 and RPSC-2. WP-1 proved to immunostain the meshwork of the B area densely, leaving the marginal zone unstained; it also reacted sparsely with the meshwork of the T-cell region. In contrast, RPSC-2 selectively immunostained the meshwork of the T region. Immuno-electron microscopy clearly visualized, for both antibodies, reaction products being deposited along the cytomembrane of the fibroblastic reticulum cells, along their abundant cytoplasmic processes that were densely intertwined with lymphocytes. Double immunostaining with RPSC-2 followed by WP-1 clearly divided the white pulp into the T and the B domains. The meshwork in the T-cell region proved to be immunostainable with both WP-1 and RPSC-2. Thus, the fibroblastic reticulum cells of the T-and the B-cell areas, while indistinguishable by routine microscopy, are at least partially heterogeneous.
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  • 163
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    Cell & tissue research 266 (1991), S. 231-238 
    ISSN: 1432-0878
    Keywords: Ciliary rootlets ; Sensilla ; Mechanoreceptors ; α-Actinin ; Centrin ; Cryofixation ; Immunohistochemistry ; Periplaneta americana, Schedorhinotermes lamanianus (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Long ciliary rootlets are a characteristic feature of the dendritic inner segments of the sensory cells in insect sensilla. These rootlets are composed of highly ordered filaments and are regularly cross-striated. Collagenase digestion and immunohistochemistry reveal that the rootlets are probably not composed of collagen fibers. However, double-labeling experiments with phalloidin and anti-α-actinins show that antibodies to α-actinin react with the ciliary rootlets of the sensilla, but do not stain the scolopale, which is composed of actin filaments as visualized by phalloidin. Antibodies to centrin, a contractile protein isolated from flagellar rootlets of green algae, also stain the ciliary rootlets. Within the ciliary rootlets of insect sensilla, α-actinin may be associated with filaments other than actin filaments. The immunohistochemical localization of a centrin-like protein suggests that contractions probably occur within the rootlets. The centrin-like protein may play a role during the mechanical transduction or adaptation of the sensilla.
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  • 164
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    Cell & tissue research 266 (1991), S. 239-245 
    ISSN: 1432-0878
    Keywords: Basal cells ; Olfactory epithelium ; Axotomy ; Immunohistochemistry ; Mouse (dd)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The olfactory epithelium of mice after axotomy was investigated to clarify the stem cells of olfactory cells by double immunostaining using antikeratin (MA903) and anti-bromodeoxyuridine (BrdU) antibodies and by conventional electron microscopy. When a single dose of BrdU was given to mice 9 days after axotomy, immunostaining for BrdU was found in the globose basal cells which were negative for MA903, but not in the basal cells proper which were positive for MA903. The BrdU-immunoreactive cells increased 3-to 6-fold over the number of these cells in the controls, indicating active cell proliferation. At other postoperative days (4 and 14 days), fewer BrdU-immunoreactive cells were found. Furthermore, three pulses of BrdU resulted in numerous BrdU-immunolabelings in the globose basal cells and a few in the basal cells proper. There was no detectable difference in the number of labeled basal cells proper in operated and unoperated mice. In the electron micrographs 9 days after axotomy, the basal cells proper, flat-shaped in unoperated mice, appeared cylindrical or pyramidal in shape and the globose basal cells often lay between the basal cells proper. In unoperated controls, the globose basal cells were located above the flat-shaped basal cells proper. The results suggest that the stem cells of the olfactory cells are globose basal cells and not basal cells proper, and that the shape of basal cells proper changes in relation to the active proliferation of stem cells.
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  • 165
    ISSN: 1432-0878
    Keywords: B cells ; Insulin ; Catecholamine ; synthesizing enzymes ; Immunohistochemistry ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The identity of the monoamine which produces a very weak formaldehyde-induced fluorescence in some pancreatic islet cells was studied by fluorescence microscopy and immunohistochemistry either on the same tissue section or on serial tissue sections of tissue from male chickens. Pancreatic islet cells showing this very weak formaldehyde-induced fluorescence react immunohistochemically with antisera directed against insulin, aromatic L-amino acid decarboxylase and dopamine beta-hydroxylase and therefore appear to be islet B cells producing insulin and noradrenaline.
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  • 166
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    Cell & tissue research 263 (1991), S. 585-587 
    ISSN: 1432-0878
    Keywords: Kidney ; Skin ; Tamm-Horsfall protein ; Immunohistochemistry ; Rana temporaria (Anura), Rat (Wistar), Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Tamm-Horsfall protein (THP) is the main protein in normal human urine, and is found in the thick limb of the Loop of Henle in human kidney, and in other mammalian species. The skin of the frog, Rana temporaria, has similar physiological properties to this mammalian kidney tissue. In the present study, an immunohistological method involving an antibody to human THP was used to investigate the distribution of this distinctive protein in frog kidney and skin, and to compare its distribution with that found in the kidney tubules of rat and rabbit. THP-positive material was detected in the distal renal tubules and nephric duct of frogs, and was also located in the superificial epidermis of skin. It is suggested that its presence in amphibian skin is consistent with the hypothesis that THP is an important component of tissues that absorb sodium and chloride ions, but remain impermeable to water.
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  • 167
    ISSN: 1432-0878
    Keywords: Salivary glands ; Innervation ; Immunohistochemistry ; Met5-enkephalin-Arg6-Gly7-Leu8 ; Tyrosine hydroxylase ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The localization of the proenkephalin A-derived octapeptide, Met5-enkephalin-Arg6-Gly7-Leu8 (MEAGL), was studied in the major salivary glands of Sprague-Dawley and Wistar rats with the indirect immunofluorescence method. MEAGL-immunoreactive nerve fibers were found around the acini, along intra-and interlobular salivary ducts and in close contact with blood vessels. In the parotid and submandibular glands tyrosine hydroxylase (TH) immunoreactivity was observed in nerve fibers around the acini, in association with intra- and interlobular salivary ducts and around blood vessels, while in the sublingual gland TH-immunoreactive nerve fibers were only seen around blood vessels. Parasympathetic neurons in submandibular ganglia contained MEAGL immunoreactivity. Moderate TH immunoreactivity was seen in some neurons of the submandibular ganglia. A subpopulation of sympathetic principal neurons in the superior cervical ganglion were immunoreactive for both MEAGL and TH. In the trigeminal ganglion, no MEAGL-immunoreactive sensory neurons or nerve fibers were observed. Superior cervical ganglionectomies resulted in a complete disappearance of TH-immunoreactive nerve fibers, while MEAGL-immunoreative nerve fibers were still present in the glands. The presence of MEAGL immunoreactivity in neurons of both sympathetic superior cervical ganglia and parasympathetic submandibular ganglia and the results of superior cervical ganglionectomies suggest, that MEAGL-immunoreactive nerve fibers in the major salivary glands of the rat have both sympathetic and parasympathetic origin.
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  • 168
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    Cell & tissue research 264 (1991), S. 161-165 
    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Pars tuberalis ; Ultrastructure ; Immunohistochemistry ; Fetal ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pars tuberalis of the adenohypophysis was investigated in three human fetuses at mid-gestation by electron microscopy or immunohistochemistry. In addition to gonadotrophs and thyrotrophs, identified by immunohistochemistry and ultrastructural morphology, electron microscopy revealed the existence of an additional differentiated cell type closely resembling “pars tuberalis-specific” cells known from other species. The role of this cell type in the human endocrine regulation remains to be elucidated.
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  • 169
    ISSN: 1432-0878
    Keywords: Neurosecretion ; Catecholamines ; HPLC ; Immunohistochemistry ; Glyoxylic acid fluorescence ; Ophryotrocha puerilis (Annelida)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the posterior part of the brain of the protandric polychaete Ophryotrocha puerilis neurosecretory cells form prominent axon terminals. The terminals are arranged in two complexes. The perikarya of these presumably monopolar neurons are scattered in the anterior part of the cerebral perikaryal layer. In females the terminals store large amounts of neurosecretory material. It has been suggested earlier that neurosecretions of the terminals may play a role during sex reversal from females to males. Application of histamine caused the release of neurosecretory material from the respective terminals in females. However, this discharge was not followed by sex reversal. Application of reserpine had no influence on the terminals. Neither by in vivo observation nor by ultrastructural analysis any effect of reserpine on the terminal complexes could be observed. In isolated terminals filled with neurosecretory material from females, catecholamines could not be detected by HPLC. Also, polyclonal antibodies against dopamine did not stain the terminal complexes. Furthermore, the complexes did not develop any fluorescence after glyoxylic acid treatment. Therefore, the present results contradict the hypothesis that the neurosecretory material of the respective axon terminals is catecholaminergic and that it is involved in sex differentiation. The function of the secretory neurons studied here remains unclear.
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  • 170
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    Cell & tissue research 264 (1991), S. 599-601 
    ISSN: 1432-0878
    Keywords: Milky spots ; Greater omentum ; Immunohistochemistry ; Macrophages ; B-lymphocytes ; Tlymphocytes ; Mast cells ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cellular composition of the human milky spots was investigated on surgically removed specimens of the greater omentum of three 8-month-old infants operated on for neuroblastoma. Monoclonal antibodies and immunohistochemical methods for recognition of macrophages, B-lymphocytes and T-lymphocytes and toluidine-blue staining for mast cells were used. The mean number of cells in one milky spot amounted to 570±33. This cell population was composed of 47.5% macrophages, 29.1% B-lymphocytes, 11.7% T-lymphocytes and 6.1% mast cells. Since inflammation was absent in the material investigated, the numerical data found in the present paper could be regarded as representative cell levels of normal milky spots.
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  • 171
    ISSN: 1432-0878
    Keywords: Brain ; Gonadotropin-releasing hormone ; Spermatogenesis ; Reproductive cycle ; Immunohistochemistry ; Development, ontogenetic ; Rana esculenta (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution and density of cell bodies and fibers immunoreactive to GnRH-like peptides were investigated in the brain of male juvenile frogs (Rana esculenta) during postmetamorphic development. An immunohistochemical technique was used, involving antisera raised against 4 variants of GnRH: mammalian GnRH, chicken GnRH-I, chicken GnRH-II and salmon GnRH. A comparison of the immunohistochemical distribution at 8 different developmental stages shows that the maximum density of immunoreactive-GnRH elements, and the full distributional complexity of this system, is attained at the completion of spermatogenesis. Immunoreactive-GnRH cell bodies first appear in the anterior preoptic area during the metamorphic climax, and then appear sequentially in the medial septal area, tegmentum and, lastly, in the retrochiasmatic area and olfactory bulb when immunoreactive-fibers also reach the cerebellum. The GnRH system reacts positively to antisera for all 4 GnRH variants, but immunoreactivity for chicken GnRH-I is the weakest.
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  • 172
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    Cell & tissue research 265 (1991), S. 11-17 
    ISSN: 1432-0878
    Keywords: Sensilla ; Mechanoreceptors ; Scolopidia ; Actin filaments ; Tropomyosin ; Cryofixation ; Immunohistochemistry ; Immunogold ultrahistochemistry ; Periplaneta americana, Schedorhinotermes lamanianus (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immuno-electron microscopy confirms that the scolopale, a characteristically prominent cytoskeletal element of insect scolopidia, is composed mainly of actin filaments. Immunohistochemistry reveals that these filaments are co-localized with tropomyosin. Myosin S1-decoration shows that their polarity is unidirectional. Antibodies to α-actinin do not bind within the scolopale. The association of these actin filaments with tropomyosin in the absence of myosin, together with their uniform polarity, strongly suggests that, in the scolopale, they have a stabilizing rather than contractile function. Filament elasticity would appear to be important for stimulation. The degree of elasticity may well be governed by the extent of tropomyosin binding.
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  • 173
    ISSN: 1432-0878
    Keywords: Chromaffin cells ; Adrenal cortex ; Steroid production ; Immunohistochemistry ; Rat (SIV, Ivanovas, FRG)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The adrenal medulla appears to exert a regulatory influence on adrenocortical steroidogenesis. We have therefore studied the morphology of rat, porcine and bovine adrenals in order to characterize the contact zones of adrenomedullary and adrenocortical tissues. The distribution of chromaffin cells located within the adrenal cortex and of cortical cells located within the adrenal medulla was investigated. Chromaffin cells were characterized by immunostaining for synaptophysin and chromogranin A, both being considered specific for neuroendocrine cells. Cortical cells were characterized by immunostaining for 17α-hydroxylase, an enzyme of the steroid pathway. Cellular contacts of chromaffin cells and cortical cells were examined at the electron microscopical level. In rat and porcine adrenals, rays of chromaffin cells, small cell clusters and single chromaffin cells or small invaginations from the medulla could be detected in all three zones of the cortex. Chromaffin cells often spread in the subcapsular space of the zona glomerulosa. In porcine and bovine adrenals, 17α-hydroxylase immunoreactive cells were localized within the medulla. Single cortical cells and small accumulations of cells were spread throughout this region. At the ultrastructural level, the chromaffin cells located within the cortex in pig and rat adrenals formed close cellular contacts with cortical cells in all three zones. Our morphological data provide evidence for a possible paracrine role of chromaffin cells; this may be important for the neuroregulation of the adrenal cortex.
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  • 174
    ISSN: 1432-0878
    Keywords: β-Pigment-dispersing hormone (β-PDH) ; Ganglia, invertebrate ; Immunohistochemistry ; Antibody staining ; Peptide localization ; Cancer antennarius, Procambarus clarkii, Panulirus interruptus (Crustacea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pigment-dispersing hormone (PDH) acts to disperse pigments within the chromatophores of crustaceans. Using an antibody raised against β-PDH from the fiddler crab Uca pugilator, we characterized the distribution of β-PDH-like immunoreactivity in the stomatogastric nervous system of five decapod crustaceans: the crabs, Cancer borealis and Cancer antennarius, the lobsters, Panulirus interruptus and Homarus americanus, and the crayfish, Procambarus clarkii. No somata were stained in the stomatogastric ganglion (STG) or the esophageal ganglion in any of these species. Intense PDH-like staining was seen in the neuropil of the STG in P. interruptus only. In all 5 species, cell bodies, processes, and neuropil within the paired circumesophageal ganglia (CGs) showed PDH-like staining; the pattern of this staining was unique for each species. In each CG, the β-PDH antibody stained: 1 large cell in C. borealis; 3 small to large cells in C. antennarius; 3–8 medium cells in P. clarkii; 1–4 small cells in H. americanus; and 13–17 small cells in P. interruptus. The smallest cell in each CG in C. antennarius sends its axon, via the inferior esophageal nerves, into the opposite CG; this pair of cells, not labeled in the other species studied, may act as bilateral coordinators of sensory or motor function. These diverse staining patterns imply some degree of evolutionary diversity among these crustaceans. A β-PDH-like peptide may act as a neuromodulator of the rhythms produced by the stomatogastric nervous system of decapod crustaceans.
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  • 175
    ISSN: 1573-0778
    Keywords: mouse-mouse hybridoma ; protein-free supplement ; basal medium ; apoptosis ; bioreactor culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The iron-rich (500 μM ferric citrate) protein-free supplement was added to six different basal media. Cell growth and monoclonal antibody production of a mouse-mouse hybridoma were investigated in 1.3 1 batch cultures performed in a laboratory bioreactor with automatic control of pH and dissolved oxygen concentration. RPMI 1640 served as the control medium. Fortification of the basal medium by balanced mixtures of amino acids and vitamins showed higher positive effect than daily supplementation by glucose and glutamine. Strongly fortified medium, based on RPMI 1640, was found superior to other basal media. The viability index increased by a factor of 3.04 and the total antibody production by a factor of 2.82, relative to the control.
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  • 176
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    Plant and soil 133 (1991), S. 209-218 
    ISSN: 1573-5036
    Keywords: Key words ; anions ; chloride ; flowers ; fruit yield ; kiwifruit ; potassium ; sulphate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The effects of K fertiliser (160 kg ha-1) applied with Cl- or SO4 2- as the accompanying anion on the K nutrition of kiwifruit (Actinidia deliciosa var. deliciosa) were assessed in a field experiment, using vines with varying degrees of K deficiency. Leaf K concentrations in spring were significantly higher for vines receiving KCl, compared to those receiving K2SO4. This effect did not interact significantly with the degree of K deficiency, and persisted for about 6 weeks. Subsequently there was no significant difference between the leaf K concentrations for the vines receiving KCl or K2SO4. Applying K as KCl increased the leaf Cl concentration, especially in spring, while applying K as K2SO4 had no significant effect on the leaf S concentration at that time. These results implied a greater requirement for organic acid anions for K+ uptake from K2SO4 than from KCl, and the importance of organic acid anions for K+ uptake from different sources of K fertiliser is discussed. This transient effect of the accompanying anion on leaf K status was associated with large effects on flowering, and fruit yields were about 28% higher for plants receiving KCl rather than K2SO4. The effects on growth and tissue nutrient composition of varying the concentrations of Cl-, NO3 -, SO4 2- and H2PO4 - around the roots of kiwifruit vines were examined in a solution culture experiment. For H2PO4 -, plant growth was very similar over a wide range of rates of addition. For the other anions, the range between deficiency and ‘toxicity’ was clearly delineated. For Cl- and NO3 -, toxicity was associated with high tissue concentrations of Cl and N, respectively, and was consistent with competition for uptake between Cl- and NO3 -. However, for SO4 2-, toxicity was associated with only a small increase in the tissue S concentration relative to that associated with maximum growth, and appeared to result more from effects on uptake of other anions and cations rather than from direct effects of high tissue S concentrations. It is concluded that the sensitivity of kiwifruit to the anion accompanying K+ in fertiliser may be related to the unusually high requirement for Cl previously reported for this species.
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  • 177
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    Plant and soil 137 (1991), S. 99-103 
    ISSN: 1573-5036
    Keywords: Key words ; Azospirillum ; beneficial bacteria ; membrance potential ; plant-bacteria interaction ; rhizosphere bacteria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Inoculation of soybean seedlings withAzospirillum brasilense Cd significantly reduced the membrane potential in every root part and was being maximal in the root elongation zone. Monitoring the proton efflux pattern of inoculated wheat roots by severalA. brasilense strains and byPseudomonas sp. for prolonged periods (up to 200h) revealed a change from the bimodal pattern of proton efflux of non inoculated roots. This change was not related to root colonization ability but to bacterial capacity to induce changes in root surface area. Continuous perfusion of the plant nutrient solution with a fresh solution (from inoculation time), eliminated the enhancing effect of inoculation on proton efflux. We propose thatA. brasilense inoculation influences membrane activity and subsequently proton efflux in roots, probably through the release of an as yet unidentified bacterial signal.
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    Plant and soil 137 (1991), S. 127-134 
    ISSN: 1573-5036
    Keywords: Key words ; ammonium ; Azospirillum sp. ; dinitrogenase reductase ; ‘switch off’
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Many N2-fixing organisms can turn off nitrogenase activity in the presence of NH4 + and turn it on again when the NH4 + is exhausted. One of the most interesting systems for accomplishing this is by covalent modification of one subunit of dinitrogenase reductase by dinitrogenase reductase ADP-ribosyltransferase (DRAT). The system can be reactivated when NH4 + is exhausted, by dinitrogenase reductase activating glycohydrolase (DRAG) which removes the inactivating group. It is fascinating that some species of the genusAzospirillum possess the DRAT and DRAG systems (A. lipoferum andA. brasilense), whereasA. amazonense in the same genus lacks DRAT and DRAG.A. amazonense responds to NH4 + but does not exhibit modification of dinitrogenase reductase characteristic of the action of DRAT. However, it has been possible to clone DRAT and DRAG and to introduce them intoA. amazonense, whereupon they become functional in this organism. The DRAT and DRAG system does not appear to function inAcetobacter diazotrophicus, an organism isolated from sugar cane, that fixes N2 at a pH as low as 3.0.A. diazotrophicus does show a rather sluggish response to NH4 +. A level of about 10 μM NH4 + is required to ‘switch off’ the system. The response to NH4 + is influenced by the dissolved oxygen concentration (DOC) as has been reported forAzospirillum sp. A DOC in equilibrium with 0.1 to 0.2 kPa O2 seems optimal for the response inA. diazotrophicus.
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  • 179
    ISSN: 1437-1596
    Keywords: Immunohistochemistry ; Salivary gland ; Specific monoclonal antibody ; ABO(H) blood group antigens ; Species identification ; Immunhistochemie ; Speicheldrüse ; spezifischer monoklonaler Antikörper ; ABH-Blutgruppenantigene ; Speziesidentifikation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Description / Table of Contents: Zusammenfassung Ein neuartiger monoklonaler Antikörper von der Maus (P4-5C) wurde entwickelt, der den Kern des Proteins erkennt, welches die ABO-Blutgruppenantigene im menschlichen Speichel trägt. Dieser erwies sich als spezifisch für menschlichen Speichel über die Benutzung immunchemischer Methoden, wie enzymgekoppelter Immunabsorptions-Test, OuchterlonyMethode, Kreuz-Elektrophorese. Durch licht- und elektronenmikroskopische Untersuchungen mit immunhistochemischen Techniken unter Verwendung dieses Antikörpers konnte gezeigt werden, daß eher spezifisch und exklusiv mit Schleim von den mukösen Zellen der menschlichen Speicheldrüsen reagiert. P4-5C reagierte weder mit mukösen Zellen anderer Primaten (Mantelpavian, japanischer Affe, Rhesus-Affe) und 4 Säugetieren (Hund, Katze, Ratte und Maus) noch mit anderen menschlichen Geweben. Das Epitop des Kernanteils des ABH-tragenden Proteins wurde definiert als P4-5C und konnte von dem Epitop der ABO-Blutgruppen-Antigene unterschieden werden mit Hilfe der Immun-Elektronenmikroskopie, obwohl diese beiden Epitope relativ nahe beieinander lokalisiert waren. Der P4-5C monoklonale Antikörper kann auch benutzt werden für die morphologische Spezies-Identifikation von Gewebsproben von den Glandulae submandibularis.
    Notes: Summary A novel mouse monoclonal antibody (P4-5C) has been developed which recognizes the core portion of the protein carrying ABO(H) blood group antigens in human saliva. This proved to be specific for human saliva using immunochemical investigations such as enzymelinked immunosorbent assay, Ouchterlony method and counter-immunoelectrophoresis. By licht and electron microscope studies with immunohistochemical techniques using this human saliva-Specific P4-5C as primary antibody, it was shown that P4-5C reacted specifically and exclusively with mucus from the mucous gland cells of human salivary glands. P4-5C reacted neither with the mucous gland cells of other primates (hamadryas baboon, Japanese monkey and Rhesus monkey) and four mammals (dog, cat, rabbit and mouse) nor with other human tissues. The epitope on the core portion of the ABO(H)-carrying protein was defined by P4-5C and could be discriminated from the epitope of ABO(H) blood group antigens using immunoelectronmicroscopy, although these 2 epitopes were localized relatively close to each other. The P4-5C monoclonal antibody can be also used for morphological species identification of tissue specimens from submandibular glands.
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  • 180
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    European archives of oto-rhino-laryngology and head & neck 248 (1991), S. 436-441 
    ISSN: 1434-4726
    Keywords: Merkel cell carcinoma ; Neuroendocrine carcinoma ; Bowen's disease ; Immunohistochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The Merkel cell carcinoma occurs primarily in the skin of the head and neck, and develops in the dermis with a trabecular growth pattern. Immunohistochemistry reveals positive staining for neuron-specific enolase, neurofilaments, cytokeratin and chromogranin A. Electron microscopically, the tumor cells contain dense-core granules, spinous cytoplasmic processes, desmosomes, zonulae adherentes and paranuclear filament aggregates besides frequent mitoses, focal necroses and lymphocyte and plasma cell infiltrates. The Merkel cell carcinoma is often co-existent with other malignancies such as squamous cell carcinoma or, as in the present study, with Bowen's disease. The definite diagnosis of the Merkel cell carcinoma can be effected only by electron microscopic examination of the tumor.
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  • 181
    ISSN: 1434-4726
    Keywords: Human endolymphatic duct and sac ; Intermediate filaments ; Cytokeratins ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Immunohistochemical detection of intermediate filament proteins and different subgroups of cytokeratins (Cks) was used to characterize the epithelium of the surgically removed adult human endolymphatic duct (ED) and sac (ES). The epithelium of the ED and ES demonstrated immunostaining for Cks 7, 8, 14, 17, 18 and 19, a pattern typical of so-called “complex” or “mixed” epithelia. This is a remarkable finding, since this pattern differs strikingly from previously reported data on the adult human cochlea and vestibular labyrinth that demonstrated a Ck pattern typical of “simple” (or single-layered) epithelia. Furthermore, the epithelium of the ED and ES demonstrated co-expression of Cks and vimentin. The present data indicate that the epithelium of the ED and ES exhibits another type of epithelial differentiation and demonstrates a higher degree of complexity than the other epithelia in the adult human inner ear.
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    European archives of oto-rhino-laryngology and head & neck 248 (1991), S. 255-258 
    ISSN: 1434-4726
    Keywords: Adenosquamous carcinoma ; Oral and pharyngeal tumors ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Four cases of adenosquamous carcinoma from the oral and pharyngeal cavities were analyzed by light microscopy and immunohistochemistry. Lymph node metastases were present in three cases. One patient died 2 years after treatment. All four carcinomas presented a mixture of squamous and glandular mucus-secreting neoplastic elements. Immunostaining for high-molecular-weight cytokeratins (KL1) was constantly positive in both squamous and glandular tumor cells. Antibodies against low-molecular-weight cytokeratins (K19) and carcinoembryonic antigen were positive only in the glandular component. The histological aspect and the immunohistochemical phenotype of these tumors is similar to the ordinary squamous cell carcinoma and adenocarcinoma, respectively.
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    European archives of oto-rhino-laryngology and head & neck 248 (1991), S. 298-301 
    ISSN: 1434-4726
    Keywords: Axotomy ; Olfactory cells ; Immunohistochemistry ; Bromodeoxyuridine ; Dividing cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To examine the dividing cells in the olfactory epithelium, an experiment using a novel immunohistochemical technique with bromodeoxyuridine (BrdU) was performed. Tissue specimens were obtained from the olfactory epithelium of guinea pigs at days 7 and 21 after olfactory nerve axotomy. BrdU uptake was detected in the epithelial cell layer directly above the basal cell layer rather than in the basal cells per se. The BrdU-immunoreactive cells were found more numerously at 7 days than at 21 days after axotomy. The basal cells showed no immunoreaction to the anti-BrdU antibody on either day. The cells reacting with the anti-BrdU antibody also showed no reaction to the anti-cytokeratin antibody used to identify the basal cells. These findings indicate that the cells showing mitotic activity have characteristics different from those of basal cells, which has been considered previously to be the precursors of regenerating olfactory receptor cells.
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  • 184
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    Proteins: Structure, Function, and Genetics 9 (1991), S. 28-36 
    ISSN: 0887-3585
    Keywords: site-directed mutagenesis ; ATP and AMP binding sites ; tryptophan fluorescence ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Site-directed mutagenesis of key amino acids of adenylate kinase has been used to suggest a new model for the location of the AMP and ATP binding sites. Phe-86 and Tyr-133, which are in close contact with the inhibitor Ap5A according to previous crystallographic results, have been independently changed to tryptophan and other amino acids. The Phe-86→Trp mutant had a 3- to 6-fold change in the Km for ATP and a 44-fold increase in the Km for AMP with a simultaneous loss of AMP substrate inhibition. Thus Phe-86 is probably in close contact with bound AMP. The Tyr-133→Trp mutant showed no large effects on enzyme kinetics and suggests that the previous assignment of Ap5A occupying natural adenosine binding sites is probably incorrect. A temperature-sensitive Leu-107→Gln mutant showed a 6-fold decrease in the Km for ATP and no effect on AMP binding, suggesting that this amino acid is near the ATP binding site.Changes in the fluorescence of single tryptophan-containing mutant enzymes provided specific information about AMP and ATP binding. The fluorescence results are consistent with the kinetic studies, and also suggest that AMP substrate inhibition is caused by the formation of an abortive complex that prevents the release of product.
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    Proteins: Structure, Function, and Genetics 9 (1991), S. 79-79 
    ISSN: 0887-3585
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Additional Material: 1 Tab.
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  • 186
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    Proteins: Structure, Function, and Genetics 9 (1991), S. 37-55 
    ISSN: 0887-3585
    Keywords: protein-protein interactions ; intersubunit binding ; hydropathy ; hydropathy complementarity ; protein interfaces ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A survey of 40 multisubunit proteins and 2 protein-protein complexes was performed to assay quantitatively the distribution of hydropathy among the exterior surface, interior, contact surface, and noncontact exterior surface of the isolated subunits. We suggest a useful way to present this distribution by using a “hydropathy level diagram.” Additionally, we have devised a function called “hydropathy complementarity” to quantitate the degree to which interacting surfaces have matching hydropathy distributions. Our survey revealed the following patters: (1) The difference in hydropathy between the interior and exterior of subunits is a fairly invariant quantity. (2) On average, the hydropathy of the contact surface is higher than that of the exterior surface, but is not greater than that of the protein as a whole. There was variation, however, among the proteins. In some instances, the contact surface was more hydrophilic than the noncontact exterior, and in a few cases the contact surface was as hydrophobic as the protein interior. (3) The average interface manifests significant hydropathy complementarity, signifying that proteins interact by placing hydrophobic centers of one surface against hydrophobic centers of the other surface, and by similarly matching hydrophilic centers. As a measure of recognition and specificity, hydropathy complementarity could be a useful tool for predicting correct docking of interacting proteins. We suggest that high hydropathy complementarity is associated with static inflexible interactions. (4) We have found that some subunits that bind predominantly through hydrophilic forces, such as hydrogen bonds, ionic pairs, and water and metal bridges, are involved in dynamic quaternary organization and allostery.
    Additional Material: 7 Ill.
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  • 187
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    Proteins: Structure, Function, and Genetics 9 (1991), S. 229-239 
    ISSN: 0887-3585
    Keywords: phospholipase A2 ; interfacial catalysis ; interfacial activation ; resonance energy transfer ; lipid-protein interaction ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Interfacial catalysis is a necessary consequence for all enzymes that act on amphipathic substrates with a strong tendency to form aggregates in aqueous dispersions. In such cases the catalytic event occurs at the interface of the aggregated substrate, the overall turnover at the interface is processive, and it is influenced the molecular organization and dynamics of the interface. Such enzymes can access the substrate only at the interface because the concentration of solitary monomers of the substrate in the aqueous phase is very low. Moreover, the microinterface between the bound enzyme and the organized substrate not only facilitates formation of the enzyme-substrate complex, but a longer residence time of the enzyme at the substrate interface also promotes high catalytic processivity.Binding of the enzyme to the substrate interface as an additional step in the overall catalytic turnover permits adaptation of the Michaelis-Menten formalism as a basis to account for the kinetics of interfacial catalysis. As shown for the action of phospholipase A2 on bilayer vesicles, binding equilibrium has two extreme kinetic consequences. During catalysis in the scooting mode the enzyme does not leave the surface of the vesicle to which it is bound. On the other hand, in the hopping mode the absorption and desorption steps are a part of the catalytic turnover.In this minireview we elaborate on the factors that control binding of pig pancreatic phospholipase A2 to the bilayer interface. Binding of PLA2 to the interface occurs through ionic interactions and is further promoted by hydrophobic interactions which probably occur along a face of the enzyme, with a hydrophobic collar and a ring of cationic residues, through which the catalytic site is accessible to substrate molecules in the bilayer. An enzyme molecule binds to the surface occupied by about 35 lipid molecules with an apparent dissociation constant of less than 0.1 pM for the enzyme on anionic vesicles compared to 10 mM on zwitterionic vesicles. Results at hand also show that aggregation or acylation of the protein is not required for the high affinity binding or catalytic interaction at the interface.
    Additional Material: 6 Ill.
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  • 188
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    New York, NY : Wiley-Blackwell
    Proteins: Structure, Function, and Genetics 10 (1991) 
    ISSN: 0887-3585
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 189
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    Proteins: Structure, Function, and Genetics 9 (1991), S. 217-224 
    ISSN: 0887-3585
    Keywords: protein-ligand interactions ; electron density ; quantum mechanics ; local density functional theory ; charge polarization ; enzymatic reaction ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The migration of electron density of a substrate (folate) on binding to an enzyme (dihydrofolate reductase) is studied by a quantum-mechanical method originally developed in solid state physics. A significant polarization of the substrate is induced by the enzyme, toward the transition state of the enzymatic reaction, at the same time giving rise to “electronic strain energy” in the substrate and enhanced protein-ligand interactions. The spatial arrangement of protein charges that induces the polarization is identified and found to be structurally conserved for bacterial and vertebrate dihydrofolate reductases.
    Additional Material: 4 Ill.
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  • 190
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    Proteins: Structure, Function, and Genetics 9 (1991), S. 240-247 
    ISSN: 0887-3585
    Keywords: hemocyanin ; Limulus ; Panulirus ; horseshoe crab ; spiny lobster ; molecular replacement ; X-ray ; crystallography ; protein structure ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Hemocyanins are copper-containing proteins that transport oxygen in a variety of invertebrates. Considerable evidence has accumulated that arthropodan hemocyanins are multimers of a fundamental hexameric unit. X-Ray crystallographic structure determination has revealed that the hemocyanin molecule from the spiny lobster Panulirus interruptus is a single hexamer having 32 point group symmetry. Using crystals of subunit II, one of 8 polypeptide types comprising the octahexameric hemocyanin of the horseshoe crab Limulus polyphemus, and the molecular replacement method for crystallographic phase determination we show that subunit II forms assemblies with the same hexameric quaternary structure as the whole Panulirus hemocyanin molecule. Observation of the same hexameric motif in two widely separated species provides strong additional evidence that this quaternary structural unit is a universal building block of arthropodan hemocyanins.
    Additional Material: 4 Ill.
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  • 191
    ISSN: 0887-3585
    Keywords: protein folding ; unfolded state ; denatured state ; hydrophobic interactions ; ring current shift ; magnetization transfer NMR ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Chemical shifts of resonances of specific protons in the 1H NMR spectrum of thermally denatured hen lysozyme have been determined by exchange correlation with assigned native state resonances in 2D NOESY spectra obtained under conditions where the two states are interconverting. There are subtle but widespread deviations of the measured shifts from the values which would be anticipated for a random coil; in the case of side chain protons these are virtually all net upfield shifts and it is shown that this may be the averaged effect of interactions with aromatic rings in a partially collapsed denatured state. In a very few cases, notably that of two sequential tryptophan residues, it is possible to interpret these effects in terms of specific, local interresidue interactions. Generally, however, there is no correlation with either native state shift perturbations or with sequence proximity to aromatic groups. Diminution of most of the residual shift perturbations on reduction of the disulfide cross-links confirms that they are not simply effects of residues adjacent in the sequence. Similar effects of chemical denaturants, with the disulfides intact, demonstrate that the shift perturbations reflect an enhanced tendency to side chain clustering in the thermally denatured state. The temperature dependences of the shift perturbations suggest that this clustering is noncooperative and is driven by small, favorable enthalpy changes. While the extent of conformational averaging is clearly much greater than that observed for a homologous protein, α-lactalbumin, in its partially folded “molten globule” state, the results clearly show that thermally denatured lysozyme differs substantially from a random coil, principally in that it is partially hydrophobically collapsed.
    Additional Material: 10 Ill.
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  • 192
    ISSN: 0887-3585
    Keywords: TIM ; protein-ligand complexes ; water involvement in binding ; drug design ; active site structure ; sleeping sickness ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Crystals of triosephosphate isomerase from Trypanosoma brucei brucei have been used in binding studies with three competitive inhibitors of the enzyme's activity. Highly refined structures have been deduced for the complexes between trypanosomal triosephosphate isomerase and a substrate analogue (glycerol-3-phosphate to 2.2 Å), a transition state analogue (3-phosphonopropionic acid to 2.6 Å), and a compound structurally related to both (3-phosphoglycerate to 2.2 Å). The active site structures of these complexes were compared with each other, and with two previously determined structures of triosephosphate isomerase either free from inhibitor or complexed with sulfate. The comparison reveals three conformations available to the “flexible loop” near the active site of triosephosphate isomerase: open (no ligand), almost closed (sulfate), and fully closed (phosphate/phosphonate complexes). Also seen to be sensitive to the nature of the active site ligand is the catalytic residue Glu-167. The side chain of this residue occupies one of two discrete conformations in each of the structures so far observed. A “swung out” conformation unsuitable for catalysis is observed when sulfate, 3-phosphoglycerate, or no ligand is bound, while a “swung in” conformation ideal for catalysis is observed in the complexes with glycerol-3-phosphate or 3-phosphonopropionate. The water structure of the active site is different in all five structures. The results are discussed with respect to the triosephosphate isomerase structure function relationship, and with respect to an on-going drug design project aimed at the selective inhibition of glycolytic enzymes of T. brucei.
    Additional Material: 12 Ill.
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  • 193
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    Proteins: Structure, Function, and Genetics 10 (1991), S. 106-116 
    ISSN: 0887-3585
    Keywords: collective motion ; hinge bending motion ; normal mode analysis ; anharmonic motion ; low-frequency motion ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A method is presented to describe the internal motions of proteins obtained from molecular dynamics or Monte Carlo simulations as motions of normal mode variables. This method calculates normal mode variables by projecting trajectories of these simulations onto the axes of normal modes and expresses the trajectories as a linear combination of normal mode variables. This method is applied to the result of the molecular dynamics and the Monte Carlo simulations of human lysozyme. The motion of the lowest frequency mode extracted from the simulations represents the hinge bending motion very faithfully. Analysis of the obtained motions of the normal mode variables provides an explanation of the anharmonic aspects of protein dynamics as due first to the anharmonicity of the actual potential energy surface near a minimum and second to trans-minimum conformational changes.
    Additional Material: 9 Ill.
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  • 194
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    Proteins: Structure, Function, and Genetics 10 (1991) 
    ISSN: 0887-3585
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 195
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    Proteins: Structure, Function, and Genetics 10 (1991), S. 156-161 
    ISSN: 0887-3585
    Keywords: synthetic metalloproteins ; protein engineering ; iso-1-cytochrome c ; metal binding ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A metal-binding site consisting of two histidines positioned His-X3-His in an α-helix has been engineered into the surface of Saccharomyces cerevisiae iso-1-cytochrome c. The synthetic metal-binding cytochrome c retains its biological activity in vivo. Its ability to bind chelated Cu(II) has been characterized by partitioning in aqueous two-phase polymer systems containing a polymer-metal complex, Cu(II)IDA-PEG, and by metal-affinity chromatography. The stability constant for the complex formed between Cu(II)IDA-PEG and the cytochrome c His-X3-His site is 5.3 × 104 M-1, which corresponds to a chelate effect that contributes 1.5 kcal mol-1 to the binding energy. Incorporation of the His-X3-His site yields a synthetic metal-binding protein whose metal affinity is sensitive to environmental conditions that alter helix structure or flexibility.
    Additional Material: 4 Ill.
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  • 196
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    Proteins: Structure, Function, and Genetics 10 (1991), S. 219-228 
    ISSN: 0887-3585
    Keywords: proline ; α-helix ; kinked α-helix ; molecular dynamics ; computer simulation ; peptide conformation stability ; protein conformational stability ; amino acid substitution ; protein architecture ; helix start/stop signal ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Free-energy simulations have been used to estimate the change in the conformational stability of short polyalanine α-helices when one of the alanines is replaced by a proline residue. For substituting proline in the middle of the helix the change in free energy of folding (ΔΔG°) was calculated as 14 kJ/mol (3.4 kcal/mol), in excellent agreement with the one available experimental value. The helix containing proline was found to be strongly kinked; the free energy for reducing the angle of the kink from 40° to 15° was calculated, and found to be small. A tendency to alternate hydrogen bonding schemes was observed in the proline-containing helix. These observations for the oligopeptide agree well with the observation of a range of kink angles (18-35°) and variety of hydrogen bonding schemes, in the rare instances where proline occurs in helices in globular proteins. For substituting proline at the N-terminus of the helix the change in free energy of folding (ΔΔG°) was calculated as -4 kJ/mol in the first helical position (N1) and +6 kJ/mol in the second helical position (N2). The observed frequent occurrence of proline in position N1 in α-helices in proteins therefore has its origin in stability differences of secondary structure. The conclusion reached here that proline may be a better helix former in position N1 than (even) alanine, and thus be a helix initiator may be testable experimentally by measurements of fraction helical conformation of individual residues in oligopeptides of appropriate sequence. The relevance of these results in regards to the frequent occurrence of proline-containing helices in certain membrane proteins is discussed.
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  • 197
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    Proteins: Structure, Function, and Genetics 10 (1991), S. 240-250 
    ISSN: 0887-3585
    Keywords: ricin ; refinement ; molecular dynamics ; molecular models ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The plant cytotoxin ricin consists of two disulfide-linked chains, each of about 30,000 daltons. An initial model based on a 2.8 Å MIR electron density map has been refined against 2.5 Å data using rounds of hand rebuilding coupled with either a restrained least squares algorithm or molecular dynamics (XPLOR). The last model (9) has an R factor of 21.6% and RMS deviations from standard bond lengths and angles of 0.021 Å and 4.67°, respectively. Refinement required several peptide segments in the original model to be adjusted translationally along the electron density. A wide range of lesser changes were also made. The RMS deviation of backbone atoms between the original and model 9 was 1.89 Å. Molecular dynamics proved to be a very powerful refinement tool. However, tests showed that it could not replace human intervention in making adjustments such as local translations of the peptide chain. The R factor is not a completely satisfactory indicator of refinement progress; difference Fouriers, when observed carefully, may be a better monitor.
    Additional Material: 4 Ill.
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  • 198
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    Proteins: Structure, Function, and Genetics 10 (1991), S. 340-358 
    ISSN: 0887-3585
    Keywords: ribonuclease A ; crambin ; conformational disorder ; protein crystallography ; simulated annealing ; X-ray refinement ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Conformational disorder in crystal structures of ribonuclease-A and crambin is studied by including two independent structures in least-squares optimizations against X-ray data. The optimizations are carried out by X-ray restrained molecular dynamics (simulated annealing refinement) and by conventional least-squares optimization. Starting from two identical structures, the optimizations against X-ray data lead to significant deviations between the two, with rms backbone displacements of 0.45 Å for refinement of ribonuclease at 1.53 Å resolution, and 0.31 Å for crambin at 0.945 Å. More than 15 independent X-ray restrained molecular dynamics runs have been carried out for ribonuclease, and the displacements between the resulting structures are highly reproducible for most atoms. These include residues with two or more conformations with significant dihedral angle differences and alternative hydrogen bonding, as well as groups of residues that undergo displacements that are suggestive of rigid-body librations. The crystallographic R-values obtained are ≈ 13%, as compared to 15.3% for a comparable refinement with a single structure. Least-squares optimization without an intervening restrained molecular dynamics stage is sufficient to reproduce most of the observed displacements. Similar results are obtained for crambin, where the higher resolution of the X-ray data allows for refinement of unconstrained individual anisotropic temperature factors. These are shown to be correlated with the displacements in the two-structure refinements.
    Additional Material: 10 Ill.
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  • 199
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    Proteins: Structure, Function, and Genetics 11 (1991), S. 35-44 
    ISSN: 0887-3585
    Keywords: microcalorimetry ; thermal stability ; lysine binding ; site-directed ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The contribution of His64 to the function and stability of tissue plasminogen activator (t-PA) kringle-2 domain (His244 in t-PA numbering) has been studied by using microcalorimetric methods to compare the ligand binding and thermal denaturation behavior of wild-type kringle-2 and mutants having His64 replaced with Tyr or Phe. This site was examined because modeling studies1 suggested that the His64 side chain could play an important role in ligand binding by forming an ion-pair with the carboxylate of the ligand, L-lysine. Kringle-2 domains were expressed by secretion of the 174-263 portion of t-PA in E. coli and purified as previously described for the wild-type domain.2 Both mutant proteins retain affinity for L-lysine, although reduced three- to four-fold relative to wild-type, demonstrating that His64 does not interact with the ligand carboxylate through an ion-pair interaction or by hydrogen bonding. The H64Y substitution does result in an altered specificity of the lysine binding site with the mutant domain having greatest affinity for a ligand of 6.8 Å chain length, whereas the wild-type domain prefers an 8.8 Å long ligand. For both wild-type and mutant, the binding of the optimal chain length ligand is dominated by enthalpic effects (ΔH = -6,000 to -7,000 cal/mol) and TΔS accounts for 〈 15% of ΔG. In addition, the H64Y mutant differs from wild-type in the effect of ligand α-amino group modification on binding affinity. Based on examination of the x-ray structure recently determined for wild-type kringle-2, the specificity changes accompanying the H64Y substitution probably result from changes in side chain interactions in the lysine binding site. Thermal denaturation experiments show that the H64Y mutant is also more stable than the wild-type protein with the difference in stabilization free energy (ΔΔG) equal to 2.7 kcal/mol at 25°C and pH 3. The increased stability of the mutant appears to be related to the difference in hydrophobicity between His and Tyr.
    Additional Material: 8 Ill.
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  • 200
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    New York, NY : Wiley-Blackwell
    Proteins: Structure, Function, and Genetics 11 (1991) 
    ISSN: 0887-3585
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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