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991.
von Hippel-Lindau disease affecting 43 members of a single kindred 总被引:22,自引:0,他引:22
We present a 6-generation kindred of over 221 members, 43 of whom were affected with von Hippel-Lindau (vHL) disease. Through a simple screening protocol, we diagnosed vHL retrospectively in 15 cases, and for the first time in 28, 11 of whom were presymptomatic. We found many complications of vHL in previously diagnosed relatives and in new cases. This study has demonstrated the utility and benefit of preventive surveillance in those known to have vHL, and of presymptomatic screening for affected relatives in families with vHL. The features of vHL were reviewed in our 43 cases and 511 cases from the medical literature. The patterns, frequencies, and ages of onset for each lesion were compared. Renal malignancies caused almost as much mortality in vHL as CNS malignancies. This family was exceptional for absence of pheochromocytoma and erythrocythemia, for more renal and pancreatic cysts and malignancies, and for slightly fewer eye or CNS lesions. Bilateral renal adenocarcinomata were found presymptomatically in five young subjects, who had bilateral nephrectomy and hemodialysis. Three survived long-term after renal transplants. Five relatives had pancreatic malignancies, which are definite although uncommon manifestations of vHL. Recommendations are made for family screening, which was economical and effective. Bayesian calculations help to predict risks for genetic counseling. The molecular basis of vHL may soon be found, since it has been linked to DNA markers on the short arm of chromosome 3. 相似文献
992.
Prostaglandins with antiproliferative activity induce the synthesis of a heat shock protein in human cells. 总被引:10,自引:2,他引:8 下载免费PDF全文
M G Santoro E Garaci C Amici 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(21):8407-8411
Prostaglandins (PGs) A1 and J2 were found to potently suppress the proliferation of human K562 erythroleukemia cells and to induce the synthesis of a 74-kDa protein (p74) that was identified as a heat shock protein related to the major 70-kDa heat shock protein group. p74 synthesis was stimulated at doses of PGA1 and PGJ2 that inhibited cell replication, and its accumulation ceased upon removal of the PG-induced proliferation block. PGs that did not affect K562 cell replication did not induce p74 synthesis. p74 was found to be localized mainly in the cytoplasm of PG-treated cells, but moderate amounts were found also in dense areas of the nucleus after PGJ2 treatment. p74 synthesis was not necessarily associated with cytotoxicity or with inhibition of cell protein synthesis. The results described support the hypothesis that synthesis of the 70-kDa heat shock proteins is associated with changes in cell proliferation. The observation that PGs can induce the synthesis of heat shock proteins expands our understanding of the mechanism of action of these compounds whose regulatory role is well known in many physiological phenomena, including the control of fever production. 相似文献
993.
Histological sections of brain from patients showing evidence of advanced pathology of Alzheimer disease (AD) were examined for the presence of herpes simplex type-1 (HSV-1) nucleic acids by a sensitive in-situ hybridization technique. Samples from neurologically normal patients were examined in parallel. Sensitivity of the assay was verified by the detection of HSV-1 nucleic acids in neurons of trigeminal ganglia taken from cases of AD and normal controls. This indicated that the hybridization reaction was sufficiently sensitive to detect latent HSV-1 infections. Positive hybridization in the brain was only detected in a confirmed case of herpes simplex virus encephalitis. These results appear to confirm previous reports that HSV-1 infection is not directly involved in the pathology associated with AD. 相似文献
994.
L G Strauss 《Der Radiologe》1989,29(7):318-321
Positron emission tomography with metabolically active substances is a noninvasive imaging modality to determine tumor metabolism. Quantification of tumor metabolism provides valuable information, e.g., for the differential diagnosis of malignancies. Radiolabeled therapeutic substances can be traced with PET. Measurement of fluorouracil metabolite concentrations provides data about the accumulation pattern of the cytostatic agent and allows assessment of the therapeutic outcome. 相似文献
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G H Bothamley J S Beck G M Schreuder J D'Amaro R R de Vries T Kardjito J Ivanyi 《The Journal of infectious diseases》1989,159(3):549-555
In the search for HLA-linked immune response genes that control susceptibility to tuberculosis, we performed HLA typing and measured antibody titers to well-defined Mycobacterium tuberculosis antigenic determinants in 101 patients with sputum smear-positive pulmonary tuberculosis and 64 healthy controls from Surabaya, Indonesia. HLA-DR2 and DQw1 were associated with sputum smear-positive pulmonary tuberculosis (attributable risk = 36% and 39%, respectively), while DQw3 was associated even more strongly with the control group (preventive fraction = 57%). Antibody titers to the TB71 and TB72 epitopes of the 38-kDa protein, present only on tubercle bacilli, were strongly associated with DR2 (Pcorr = .001 and .024, respectively). The association of both the disease and the antibody response to the 38-kDa antigen of M. tuberculosis with Class II HLA genes HLA-DR2 indicates that Ir-gene-mediated regulation of the immune response to this antigen may be of pathogenic significance for the development of sputum smear-positive tuberculosis. 相似文献
999.
1000.
Skeletal muscle blood flow and venous capacitance in patients with severe sepsis and systemic hypoperfusion 总被引:2,自引:0,他引:2
Alterations in peripheral vascular tone are presumed to contribute to circulatory failure during severe sepsis. Decreased venous tone with venous pooling may decrease effective circulatory blood volume, while decreased arterial tone with redistribution of systemic blood may compromise tissue nutrient flow. We compared forearm arterial and venous tone and forearm blood flow in ten patients with and ten patients without sepsis. The FVT, MVC, and FBF were measured by air plethysmography. In the septic patients, MCV was 1.4 +/- 0.1 ml compared with 3.1 +/- 0.2 ml in nonseptic patients (p less than 0.01). The FVT was 13.4 +/- 1.0 mm Hg/ml in septic patients versus 7.0 +/- 0.5 mm Hg/ml in nonseptic patients (p less than 0.01). The ratio of FBF to cardiac output was 0.28 +/- 0.07 percent in septic patients and 0.31 +/- 0.07 percent in nonseptic patients. These data suggest that increased peripheral venous capacitance and redistribution of skeletal muscle blood flow are not present in patients with sepsis. 相似文献