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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-2307
    Keywords: Endocrine tissues ; Endocrine tumours ; Cytoskeleton ; Immunohistochemistry ; Gel-electrophoresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The presence and distribution of intermediate filament proteins, such as cytokeratins, vimentin, neurofilament proteins and glial fibrillary acidic protein were assessed immunohistochemically in pituitary adenomas, medullary thyroid carcinomas, endocrine pancreatic tumours, gastric, intestinal and bronchial carcinoids, parathyroid adenomas, pheochromocytomas, paragangliomas and related non-neoplastic tissues. In some cases, immunohistochemical results were correlated with cytoskeletal proteins as analysed by SDS-polyacrylamide gel electrophoresis. Cytokeratin antibodies with broad range of immunoreactivity (i.e. to murine liver cytokeratin component D) reacted with epithelial cells in all non-neoplastic endocrine tissues and related neuroendocrine tumours studied, except for adrenal medulla, pheochromocytoma and paraganglioma, independently of hormone production and biological behaviour. In contrast, antibodies to epidermis-derived cytokeratins failed to stain endocrine tissues and tumours. Paranuclear cytokeratin accumulations were seen in bronchial, gastric, and intestinal carcinoids and seem to be a common feature of neuroendocrine tumours. One-and two-dimensional SDS-polyacrylamide gel electrophoresis of non-neoplastic endocrine tissues and related tumours revealed two major keratin polypeptides corresponding to cytokeratins No. 8 and 18 of the cytokeratin catalog of human cells (Moll et al. 1982). According to this cytokeratin polypeptide composition, endocrine tissues and related tumours conform to the “simple type” of epithelia. Vimentin-related immunoreactivity was restricted to stromal cells and to folliculo-stellate cells in normal pituitary gland, Schwann cells in carcinoids and satellite cells in normal adrenal medulla and in pheochromocytomas. Neurofilament protein- (70 kD)-antibodies only stained nerve fibers in normal tissues and at the periphery of carcinoid tumour cell complexes, and, to a variable degree, cells in nontumorous adrenal medulla, pheochromocytomas and paragangliomas. Furthermore, neurofilament reactivity was observed along with cytokeratin expression in two bronchial carcinoids.
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  • 4
    ISSN: 1432-2307
    Keywords: Gastrointestinal carcinomas ; Tissue polypeptide antigen (TPA) ; Cytokeratins ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The presence and distribution of tissue polypeptide antigen (TPA) were assessed in gastrointestinal carcinomas of different origin, morphology and degree of differentiation. Immunocytochemistry was employed, using the PAP technique on formalin-fixed, paraffin-embedded material and compared with the results obtained with antibodies to cytokeratins. Like cytokeratins, TPA was a reliable marker of epithelial differentiation and showed tissue distribution patterns similar to cytokeratins, as revealed by antibodies with broad-range cytokeratin immunoreactivity. In most carcinomas, TPA-specific immunostaining was less intense than in non-neoplastic tissue. No direct relationship between intensity of TPA staining and morphological degree of differentiation and proliferation was found. TPA staining was most pronounced at the periphery of the cells. In stratified epithelium, i.e. oesophageal mucosa, basally located cells exceeded superficial cells in TPA immunoreactivity in contrast to the cytokeratin antibodies which decorated the more superficially placed cell layers. TPA and cytokeratin staining patterns were similar in neoplastic and non-neoplastic gastric, intestinal mucosa, as well as in biliary tract epithelium. Antral and cardial mucoid glands of the stomach as well as gastric carcinomas of the pylorocardial type remained unstained with both types of antibodies. Similar staining with TPA and cytokeratin antibodies was also observed in pancreatic and liver tissue. In this study, hepatocytes were, although weakly, stained by TPA antibodies and an identical staining was found with benign and malignant hepatocellular neoplasms. Ductal and ductular TPA-staining was most conspicuous and so was the immunoreactivity of cholangiocellular carcinomas. A comparison between TPA and cytokeratins was also made by immunoblotting which revealed immunoreactivity of antibodies to TPA with cytokeratin polypeptides of different species (man, mouse) and organs (epidermis, liver), particularly with the cytokeratin component 8 of human liver and the related component A of mouse liver. The significance of this finding is uncertain until the pertinent epitopes have been revealed by monoclonal mapping of the components which exhibit similar molecular weights by SDS polyacrylamide gel electrophoresis.
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  • 5
    ISSN: 1432-2307
    Keywords: Intermediate filaments ; Desmosomes ; Testicular tumours Germ cell tumours ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Seminomas and non-seminomatous testicular germ cell tumours were studied for the presence of cytokeratin and vimentin filaments and desmosomes using immunohistochemical methods. In the majority of the classical seminomas and in seminomatous areas of mixed tumours most tumour cells appeared to lack cytokeratin filaments. Some seminomas contained a focally variable proportion of cells exhibiting cytokeratin-positive structures while other cases contained only few seminoma cells with a well developed fibrillar cytokeratin network. Gel electrophoresis of cytoskeletal proteins from microdissected regions revealed cytokeratin polypeptides nos. 8 and 18 typical of simple epithelia. In one seminoma, however, all, or almost all, tumour cells contained cytokeratin filaments. This finding is in line with the assumption of transitional forms between seminoma and embryonal carcinoma. Despite the lack - or variable expression - of cytokeratin filaments most seminoma cells contained desmosomes, although often few in number and irregularly distributed at the circumference of the cells. Loosely arranged and often very sparse vimentin fibrils were found in many, but not all seminoma cells. Double label immunofluorescence microscopy suggested that the majority of desmosomes was associated with intermediate filaments of the vimentin type. In contrast, in carcinoma cells of malignant teratomas, in well differentiated epithelial cells of intermediate-type malignant teratomas and in trophoblastic cells present in trophoblastic-type malignant teratomas cytokeratin filament bundles as well as desmosomes were decorated. The arrangement and density of the cytokeratin filament skeleton and of desmosomes varied with degree of maturation of the tissue. The most regular distribution and intensive staining of cytokeratin filaments and desmoplakin was found in “mature” tissues. Vimentin was demonstrated in mesenchymal areas and stroma cells. The results show that seminomas are distinguished from most other germ cell and non-germ cell tumours by the presence of true desmosomes together with scanty vimentin filaments in most tumour cells. In addition, they indicate that seminoma cells can be heterogenous in their cytoskeletal complement and may include cells with cytokeratin expression, indicative of a multi-potential character of the initially transformed cell(s).
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  • 6
    ISSN: 1432-2307
    Keywords: Cutaneous neuroendocrine carcinoma ; Immunocytochemistry ; Gel electrophoresis ; Cytoskeleton ; Intermediate filaments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The presence and distribution of cytokeratins, neurofilament proteins, vimentin and glial fibrillary acidic protein were studied in 10 cutaneous neuroendocrine carcinomas (CNEC) by immunohistochemical techniques, using specific antibodies. In all cases tumour cells were specifically stained with antibodies to mouse liver cytokeratin component D in paraffin-embedded formalin-fixed and frozen sections. Moreover, one- and two-dimensional SDS-polyacrylamide gel electrophoresis of high salt/detergent resistant cytoskeletal residues from tumour material, isolated by microdissection from frozen sections, revealed the presence of cytokeratin components 8 and 18 which are characteristic constitutents of cytokeratin filaments of simple epithalia. Neurofilament proteins were detected by immunocytochemistry in tumour cells from 2 patients, from whom frozen material was available, and their presence was also positively identified in cytoskeletal residues by immunoblotting using specific antibodies. Glial fibrillary acidic protein and vimentin could not be demonstrated in tumour cells. Our studies did not confirm the suggested origin of CNEC from epidermal Merkel cells.
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  • 7
    ISSN: 1420-9071
    Keywords: Human lymphocytes ; X-irradiations ; blood storage ; chromosome aberrations ; fluorescence plus Giemsa staining ; cytogenetic dosimetry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Human whole blood was irradiated with 2.5 Gy of 220 kVp X-rays and stored before culture with 9.7 μM BrdU and 19.4 or 38.7 μM BrdU for 0, 24, 48 and 72 h. The frequency of dicentrics and ring chromosomes was determined in cells staining as first division (M1) metaphases with the fluorescence plus Giemsa technique. Storage had no influence on the observed aberration yields in 44 h cultures containing 9.7 μM BrdU. In 66 h cultures at 19.4 μM BrdU the observed yields after 2 and 3 days' storage were significantly lower as compared to cultures from fresh blood. No storage effect was revealed in 66 h cultures containing 38.7 μM BrdU. In cases where cytogenetic radiation dosimetry has to be carried out using blood samples which have been in transit for 2–3 days, the findings are of relevance for a correct determination of the chromosome damage in M1 cells.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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