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Biomedical subjects

A Beham

Publications and source records attributed to A Beham.

120 records · Page 7Linked to original sources

[Immunohistochemical studies in the differential diagnosis of malignant fibrous histiocytoma].

Malignant fibrous histiocytomas (MFH) belong to the most frequent soft tissue tumours in adults and have to be discriminated from other tumours with similar morphology. Various tumour markers aid the differential diagnosis. Twenty cases of MFH were studied immunohistochemically using antibodies to vimentin, TPA, desmin, lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, S-100 protein, neurone-specific enolase (NSE), laminin, fibronectin and ferritin. Vimentin and lysozyme were found in the tumour cells of all, alpha 1-antitrypsin of 18, alpha 1-antichymotrypsin of 19, fibronectin of 16 and ferritin of 12 cases. Antibodies of TPA, desmin, S-100 protein, NSE and laminin did not reveal positive immunoreactivity. Exclusion of spindle-cell carcinoma can be made by positive vimentin and negative TPA reactivity, of melanoma by negative S-100 reactivity, and of leio- and rhabdomyosarcoma by lack of desmin immunoreactivity. Schwannomas contain S-100 protein, but lack lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin and fibronectin. Pleomorphic liposarcomas cannot be distinguished from MFH on the basis of immunohistochemical staining. Vimentin, alpha 1-antitrypsin, alpha 1-antichymotrypsin and fibronectin can, therefore, be regarded as useful markers in the differential diagnosis of MFH.

Adult↗

[Immunohistochemical studies on the occurrence of HBs antigen in alcoholic fatty liver and alcoholic fatty liver hepatitis].

120 liver biopsies of alcoholic fatty liver, alcoholic hepatitis and cirrhosis were studied immunohistochemically with regard to the occurrence of HBs-antigen. In no instance HBs-antigen was detected. These findings suggest neither a major influence of hepatitis B-virus on the progression of alcoholic liver cell damage nor a defect in immunologic responsiveness to hepatitis B-virus component in the alcoholic.

Adult↗

Distribution of TPA and cytokeratins in gastrointestinal carcinomas as revealed by immunohistochemistry.

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.

Antigens, Neoplasm↗

Alveolar rhabdomyosarcoma in a young female patient metastasizing to the brain.

A case of 14-year-old girl is reported in whom an alveolar rhabdomyosarcoma occurred in the soft tissues of the left forearm 4 years prior to death. Despite extensive surgery as well as chemotherapy and radiotherapy the tumor recurred locally and produced extensive metastases including a metastasis to the brain. Cerebral metastases have not yet been reported in the literature despite extensive reports on the pathology of alveolar rhabdomyosarcoma. The morphological diagnosis of rhabdomyosarcoma was supported by the immunohistochemical demonstration of desmin, myosin, and myoglobin in the tumor cells.

Adolescent↗

[Rupture in myocardial infarct: predisposing factors?].

The clinical, electrocardiographic and pathomorphologic findings of 37 patients with cardiac rupture and of 40 consecutive patients who died from other causes during acute myocardial infarction were analyzed in regard to predisposing factors for myocardial rupture. Useful diagnostic parameters, to assess the risk of myocardial rupture could not be identified. Pacemaker therapy for bradycardia did not increase the risk of myocardial rupture.

Aged↗

[Bacteriological and technical testing of an 0.2-micrometer air-eliminating infusion filter (author's transl)].

The elimination of bacteria from an i.v. solution and the flow rate of different solutions were tested using an 0.2 micrometer Pall Ultipor Filter. The filtration under the influence of gravity as well as under the increased trans-filter pressure was able to eliminate microbial contamination completely. In a second test an interdependence between viscosity and the flow rate of solutions could be shown.

Bacteria↗

The distribution of intermediate filament proteins, actin and desmoplakins in human placental tissue as revealed by polyclonal and monoclonal antibodies.

The distribution of intermediate filament proteins (cytokeratin, vimentin, desmin), actin, and desmoplakins in various placental compartments was studied by immunofluorescence microscopy using polyclonal and monoclonal antibodies. Trophoblast cells (cytotrophoblast, syncytiotrophoblast, isolated trophoblast cells, trophoblastic giant cells) were strongly stained by all types of cytokeratin antibodies. Antibodies to desmoplakins revealed the presence of desmosomes at all membranes, except the basal membrane of cytotrophoblast cells, and at the basal as well as the lumen-oriented membrane of the syncytiotrophoblast. After disappearance of the cytotrophoblast cell layer the distribution of desmosomes in the syncytiotrophoblast was unaltered. Isolated trophoblast cells contained desmosomes around their entire circumference. Amnion epithelial cells were heterogeneous with respect to cytokeratin composition as revealed, for example, by polyclonal antibodies with a broad range of cytokeratin reactivity and by monoclonal antibodies to cytokeratin No. 18. With the latter, a heterogeneous staining of amnion epithelial cells was achieved. Desmosomes (spots reactive with desmoplakin antibodies) were present at the lateral membranes of the amnion epithelial cells. In addition, vimentin filaments were coexpressed in these cells. Large vessels of the chorionic plate and stem villi showed thick walls consisting of vimentin-, desmin- and actin-positive cells. They were surrounded by mantles rich in vimentin-, desmin- and actin-positive cells, resembling myofibroblasts. This indicates that these cells may play a role in villous contractility and modulation of the intervillous space with effect on both maternal and fetal placental circulation.

Actins↗