[Carcinoid of the ductus choledochus. A rare cause of obstructive jaundice].
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Biomedical subjects
Publications and source records attributed to W J Hofmann.
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Reactive germinal-center B cells completely lack vimentin. This observation made by using monoclonal vimentin antibody V9 and a sensitive immunoperoxidase technique led to the investigation of vimentin expression in an unselected series of 73 immunohistochemically proven B cell lymphomas. While small lymphocytic lymphomas regularly expressed vimentin, the neoplastic population of mixed, small and large, and large cell lymphomas often contained various proportions of vimentin-negative tumor cells or failed to express it at all. Against the background of the Lukes-Collins classification and the Kiel classification, both defining and subdividing follicular center-cell lymphomas, there were statistically highly significant correlations between the absence of vimentin and the histology, suggesting a germinal center origin. Our data suggest that loss of vimentin expression is indicative of the transient, follicular center-cell stage of normal and malignant B lymphocytic transformation. The complete absence of vimentin within the neoplastic population of all Burkitt's lymphoma cases examined may serve as an argument for its follicular center stage of differentiation, as was asserted by Lukes and Collins.
The condition of true thymic hyperplasia is defined as an increase of both size and weight of the gland while it maintains normal microscopic architecture. It occurs in three different clinicopathologic forms: True thymic hyperplasia without any other disease is extremely rare and only seven well documented examples could be found in a review of the literature. Enlargement of the thymus gland is reported as a form of rebound phenomenon in a number of conditions like recovery from severe stress situations, after administration of steroids, and after treatment of malignant tumors. Finally, thymic hyperplasia has been described in association with endocrine abnormalities, sarcoidosis, and Beckwith-Wiedeman syndrome.
The so-called lymphofollicular hyperplasia, which is caused by the occurrence of hyperplastic lymph follicles within the organ, is constantly associated with autoimmune diseases (e.g., myasthenia gravis) and in rare instances with malignant tumors. The architecture of lymphofollicular hyperplasia was studied immunohistochemically using antibodies against epithelial, vascular, lymphocytic, and histiocytic antigens. There is evidence, that the configuration, microtopography, cellular composition, and immunohistological findings of the lymph follicles with germinal centers in the myasthenic thymus are essentially the same as in those occurring in lymph nodes and in other lymphatic tissue. Furthermore it could be shown that the follicles originate in the interlobular septal space and displace the thymic parenchyma by extension.
A five-year-old, normally developed boy who had been healthy except for an absence epilepsy prior to valproate (VPA) treatment died 16 weeks after the introduction of VPA-monotherapy due to liver failure and intractable bleeding disorder. This case emphasizes that the restriction of VPA-therapy to children of more than two years of age, on monotherapy, and without evidence of other diseases or retardation does not exclude fatal complications. Until today world-wide about 100 patients have died during VPA-treatment.
This is a report on 8 mediastinal tumours that occurred in young adults (19-43 years, mean: 29.4); predominantly in females (6/8). Initial symptoms consisted of thoracic pain and venectasia and in only one case in B symptoms. After surgical tumour reduction, radiation and/or chemotherapy, local recurrence was observed in each case under clinical care; abdominal spread is presently suspected in 3 patients; 3 died 11, 13 and 22 months after diagnosis. None developed leukaemia. The tumours are B-cell neoplasms with a characteristic immunophenotype: leucocyte common antigen+, common acute lymphoblastic leukaemia antigen-, B 1-antigen+, surface and cytoplasmic immunoglobulin-. Flow cytometry revealed DNA-diploidy in 7 cases and a moderately (3.2-3.8%) to extremely high (8.0-20.6%) S-phase component. The proliferation associated antigen Ki67 was detectable in 10-60% of the tumour cell nuclei, thus stressing the considerable or rapid growth. Histopathology is characterized by a diffuse growth pattern and a clearness and abundance of cytoplasm of the pleomorphic tumour cells, which vary in size and nuclear morphology from patient to patient. Apoptoses are more numerous than mitoses. Fibrosis and focal necrosis are common, sclerosis is present in 3 cases. We suggest that primary mediastinal lymphoma of B cell type is a novel B-lymphoma variant.
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Pedal artery bypass has proven to be a safe, simple and durable procedure. Failure of a pedal artery reconstruction seldom results in an amputation that is more proximal than it would have been without previous attempted bypass. Thus an aggressive strategy in the revascularisation of the forefoot in case if critical ischemia based on tibial occlusive disease is worthwhile.
The data of 16 children who died while receiving valproate (VPA) therapy in West Germany were analyzed. Five were normally developed, 5 were receiving VPA-monotherapy, and only 2 patients were aged less than 3 years. The first clinical symptoms of impending hepatotoxicity usually included nausea, vomiting, and apathy; pathologic laboratory tests reflected liver failure. Liver histology revealed microvesicular steatosis, cell necrosis, and bile duct proliferation of varying degree. An abnormal metabolite, 4-ene-VPA, was detected in all examined patients (six of six) and persisted after drug withdrawal. The pathogenesis of fatal liver failure during VPA treatment remains unknown. World-wide, approximately 100 fatalities have been reported in relation to VPA treatment. More than 90% were aged less than 20 years, 95% developed their first symptoms within the first 6 months of treatment, and 16 were treated with VPA alone. Since it is difficult precisely to define a group at risk for fatalities with VPA, careful clinical and laboratory monitoring with a special focus on vomiting and apathy, liver enzymes, and coagulation tests seem mandatory during the first 6 months after introduction of VPA. Taking into account the considerable number of fatalities during VPA treatment, the indication for its use requires careful reevaluation.