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31.
Summary The distribution of a neuronal specific enolase (14-3-2) in the central nervous system (CNS) lesions of tuberous sclerosis (TS) was examined using antiserum to 14-3-2 and the peroxidase antiperoxidase (PAP) method of Sternberger. In cortical tubers all the giant cells had intense cytoplasmic staining. Only occasional cells in the subependymal nodules were stained. All cells in the subependymal giant cell tumors were intensely stained. This indicates that the cortical giant cells and the giant cell subependymal tumors are of neuronal rather than astrocytic origin. 相似文献
32.
Phospholipase A2 (PLA2) isoenzymes from Naja nigricollis venom exhibit anticoagulant activity with varying potencies. To determine which complexes in the extrinsic coagulation cascade are inhibited by these PLA2 enzymes, we examined their effects on the coagulation of bovine plasma initiated by the addition of thromboplastin, Russell's viper venom (RVV) or thrombin. The weakly anticoagulant PLA2 enzymes, CM-I and CM-II, prolonged clotting initiated by thromboplastin, but not that initiated by RVV or thrombin. The strongly anticoagulant enzyme, CM-IV, prolonged clotting initiated by both thromboplastin and RVV, but not clotting initiated by thrombin. To confirm the differences in their inhibitory properties, we examined the effect of these PLA2 enzymes on reconstituted extrinsic tenase and prothrombinase complexes. The weakly anticoagulant enzymes inhibited the tenase complex, but did not inhibit the prothrombinase complex, whereas the strongly anticoagulant enzyme inhibited both complexes. Thus the enzymes showed distinct differences in their inhibition patterns in the extrinsic coagulation cascade. Their dissimilarity in inhibition of the two phospholipid dependent activation steps probably reflects the difference in phospholipid requirements and/or mechanism of inhibition between the two complexes. Inhibition of successive amplification steps in the extrinsic coagulation cascade by CM-IV is consistent with its potency as a strongly anticoagulant PLA2. 相似文献
33.
Neovascularization of the iris: an experimental model in cats 总被引:2,自引:0,他引:2
E Stefansson M B Landers M L Wolbarsht G K Klintworth 《Investigative ophthalmology & visual science》1984,25(3):361-364
Neovascularization of the iris was induced in cats by removing the vitreous and lens and creating a rhegmatogenous retinal detachment. The presence of new blood vessels on the anterior surface of the iris was verified from the second month onward by slit lamp examination, as well as by light microscopy six to twelve months after the operation. Control eyes undergoing vitrectomy and lensectomy, but without retinal detachment, did not develop rubeosis iridis. This model may allow investigation into causes and therapy of rubeosis iridis. 相似文献
34.
Angiogenesis is essential for tumor growth, invasion, and metastatic spread. Whereas microvessel density (MVD) has been widely used as a measure of tumor-associated angiogenesis, we now wanted to examine the significance of other angiogenic markers, especially vascular proliferation (by Ki-67/factor VIII staining) and the degree of pericyte coverage [by alpha-smooth muscle actin (alpha-SMA)/factor VIII staining], in a large and population-based series of endometrial carcinoma with complete follow-up. Due to limited information on the role of lymphangiogenesis in these tumors, lymphatic vessel density (LVD) by LYVE-1 staining was also determined, as well as selected angiogenic factors [vascular endothelial growth factor (VEGF)-A, VEGF-C, VEGF-D and basic fibroblast growth factor (bFGF)], which could possibly be related to vascular proliferation and lymphangiogenesis. The information on angiogenic phenotype was related to clinicopathologic features and disease progress. Median vascular proliferation, as estimated by vascular proliferation index (VPI), was 3.9% and high VPI was associated with features of aggressive tumors and decreased survival. The prognostic effect of VPI was superior to that of MVD. Presence of pericyte coverage, as estimated by the alpha-SMA index (SMAI), was 35% and low SMAI was significantly associated with vascular invasion by tumor cells and impaired prognosis. Peritumoral lymphatic vessels (LVD-pt) were found in 39.5% of the cases and high LVD-pt was significantly associated with aggressive tumor features and decreased survival. In multivariate survival analysis, only the extent of vascular proliferation had independent prognostic effect, in addition to well-known clinicopathologic factors, whereas MVD did not have significant prognostic value. In conclusion, our study indicates that vascular proliferation is a meaningful variable in assessing the angiogenic phenotype of endometrial carcinoma. 相似文献
35.
Stefansson T Moller PH Sigurdsson F Steingrimsson E Eldon BJ 《International journal of cancer. Journal international du cancer》2006,119(2):304-308
The aim of this study was to characterize the familial risk of colon and rectal cancer using 2 population-based registries in Iceland, the Icelandic Cancer Registry and a genealogy database. The standardized incidence ratio (SIR) was used to estimate the risk among relatives of colorectal cancer index cases diagnosed in Iceland over a 46-year period (1955-2000). The 2,770 colorectal cancer patients had 23,272 first-degree relatives. Among first-degree relatives, there was an increased risk of both colon (SIR 1.47, 95% confidence interval (CI) 1.34-1.62) and rectal cancer (SIR 1.24, 95% CI 1.04-1.47). An increased risk of colon cancer was observed among siblings of colon cancer patients (SIR 2.03, 95% CI 1.76-2.33), whereas no such increase was observed for parents or offspring. Furthermore, the risk of rectal cancer was only increased among brothers (SIR 2.46 95% CI 1.46-3.89) of rectal cancer patients and not among their sisters (SIR 1.0 95% CI 0.40-2.06). The added risk of colon cancer among first-degree relatives was independent of site of colon cancer in the proband. Our results confirm that family history of colorectal cancer is a risk factor for the disease. However, family history has a different association with colon cancer than with rectal cancer, suggesting that the 2 cancer types may have different etiologic factors. Our results have implications for colon and rectal cancer screening programs. 相似文献
36.
Stefansson IM Salvesen HB Akslen LA 《International journal of cancer. Journal international du cancer》2006,118(5):1227-1233
p63 and cytokeratin (CK) 5/6 are markers of basal and squamous differentiation in several normal epithelia and human tumors and are also suggested to be markers of progenitor or stem cells in certain stratified epithelia. In endometrial carcinoma, there is very limited information about the expression pattern of p63 or CK5/6 and no prognostic information. The aim of our study was to examine whether the expression of these markers was associated with a certain tumor phenotype in terms of other biomarkers, clinicopathologic characteristics and patient prognosis. Immunohistochemical expression of p63 and CK5/6 was examined using tissue microarrays (TMAs) in a large population-based series of 276 endometrial carcinomas with long and complete follow-up. Selected cases of normal and hyperplastic endometrium were examined for comparison (n = 15). Absence of p63 expression (70%) was significantly associated with nonendometrioid carcinomas, high histologic grade (FIGO), higher mitotic count and tumor cell proliferation by Ki-67, microsatellite instability (MSI) and loss of hMSH6 expression. A tendency toward reduced patient survival was also seen (p = 0.098). Presence of CK5/6 expression was more frequent in endometrioid tumors with squamous differentiation, while loss of CK5/6 expression (54%) was significantly associated with high FIGO stage, reduced beta-catenin expression, MSI and reduced patient survival (p = 0.0001); the latter was also found within the endometrioid subgroup (p = 0.0004). Multivariate survival analysis revealed that loss of CK5/6 expression had an independent prognostic impact in addition to well-known prognostic variables. Expression of both markers was increased in simple hyperplasia compared with normal endometrium. In complex hyperplasia, p63 expression was also increased, whereas CK5/6 was positive in areas with squamous differentiation only. Thus, loss of p63 or CK5/6 was associated with features of aggressive tumors, and lack of CK5/6 was significantly associated with reduced survival in multivariate analysis. 相似文献
37.
J P Antel J Kuchibhotla K Stefansson 《Journal of neuropathology and experimental neurology》1985,44(6):533-545
We used formalin-fixed human spinal cord and dorsal root ganglia as immunogens to generate monoclonal antibodies (mAb) which immunohistochemically react with neurons in formalin-fixed human tissue sections. Three of the mAb recognized all neuronal populations studied, including those in spinal cord, dorsal root ganglia, cerebellum, and cerebrum. A fourth mAb recognized neurons within spinal cord, dorsal root ganglia and dentate nucleus of cerebellum but not those in cerebrum or cerebellar hemispheres. This mAb, unlike the other three, did not recognize murine neurons. These data indicate the feasibility of generating mAb suitable for analysis of human pathological material in its most readily available form, formalin-fixed paraffin-embedded tissue. 相似文献
38.
Chronic intraocular infection following cataract extraction and intraocular lens (IOL) implantation has been documented by several authors. We report a case of chronic, bacterial endophthalmitis that clinically correlates with previous pathologic studies in which the focus of infection was sequestered in the capsular sac between the IOL and the posterior lens capsule. Successful management did not require IOL removal. 相似文献
39.
Kari Stefansson Jack P. Antei Joel Oger James Burns AvertanoB. C. Noronha Raymond P. Roos Barry G. W. Arnason G. Gudmundsson 《Annals of neurology》1980,7(5):436-440
Selected Properties of Peripheral blood lymphocytes (PBLs) from five ambulatory affected individuals of a kindred with autosomal dominant cerebrovascular amyloidosis were studied. The percentage of PBLs bearing surface membrane immunoglobulin (SmIg + cells) was increased in the patient group (30 ± 3% versus 20 ± 2%; p < 0.05). The Percentage of PBLs forming early and total E-rosettes was comparable in patient and control groups. Mitogenic response to concanavalin A (Con A) was suggestively reduced in the patient group, measured both by total 3Hthymidine incorporation and by comparison of stimulation indices. Mitogenic response to phytohemagglutinin and pokeweed was comparable in the two groups. Capping of Con A by PBLs was significantly reduced in the patient group compared with the controls (13 ± 1% versus 26 ± 2%; p < 0.01). The findings of reduced Con A response and increased SmIg+ cells support the hypothesis that immune dysfunction contributes to the development of amyloidosis. The reduced capping suggests altered membrane properties in this autosomal dominant disorder. 相似文献
40.
N A Busis J J Halperin K Stefansson D J Kwiatkowski S M Sagar S R Schiff E L Logigian 《Neurology》1985,35(5):679-683
A mother and son had peripheral neuropathy, abnormal elevation of serum IgM, and paraproteinemia. These patients may have a familial disorder of immune regulation with antibody-mediated neuropathy or a familial neuropathy with a secondary immune response. 相似文献