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1.
Almost 90% of primary acute pericarditis are idiopathic. Between specifics forms, a very low percentage of cases are due to chronic rheumatic diseases. A case of adult Still's disease (juvenile chronic rheumatoid arthritis) with acute pericarditis being the first clinical manifestation (besides fever and general syndrome) is presented. Therapy with oral prednisone was rapidly effective, and pericardial effusion resolved after 3 weeks of treatment, as echocardiography showed.  相似文献   
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Early during rat thymus ontogeny, an important proportion of thymocytes expresses IL-2R and contains IL-2 mRNA. To investigate the role of the IL-2-IL-2R complex in rat T cell maturation, we supplied either recombinant rat IL-2 or blocking anti-CD25 mAb to rat fetal thymus organ cultures (FTOC) under several experimental conditions. The IL-2 treatment initially stimulated the growth of thymocytes and, as a result, induced T cell differentiation, but the continuous addition of IL-2 to rat FTOC, as well as the anti-CD25 administration, resulted in cell number decrease and inhibition of thymocyte maturation. These results indicate that immature rat thymocytes bear functional high- affinity IL-2R and that IL-2 promotes T cell differentiation as a consequence of its capacity to stimulate cell proliferation. Modifications in TCR alpha beta repertoire and increased numbers of NKR- P1+ cells, largely NK cells, were also observed in IL-2-treated FTOC. Furthermore, IL-2-responsiveness of different thymocyte subsets changed throughout thymic ontogeny. Immature CD4-CD8-cells responded to IL-2 in two stages, early in thymus development and around birth, in correlation with the maturation of two distinct waves of thymic cell progenitors. Mature CD8+ thymocytes maximally responded to IL-2 around birth, supporting a role for IL-2 in the increased proliferation of mature thymocytes observed in vivo in the perinatal period. Taken together, these findings support a role for IL-2 in rat T cell development.   相似文献   
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BAG1 over-expression in brain protects against stroke   总被引:3,自引:0,他引:3  
The co-chaperone BAG1 binds and regulates 70 kDa heat shock proteins (Hsp70/Hsc70) and exhibits cytoprotective activity in cell culture models. Recently, we observed that BAG1 expression is induced during neuronal differentiation in the developing brain. However, the in vivo effects of BAG1 during development and after maturation of the central nervous system have never been examined. We generated transgenic mice over-expressing BAG1 in neurons. While brain development was essentially normal, cultured cortical neurons from transgenic animals exhibited resistance to glutamate-induced, apoptotic neuronal death. Moreover, in an in vivo stroke model involving transient middle cerebral artery occlusion, BAG1 transgenic mice demonstrated decreased mortality and substantially reduced infarct volumes compared to wild-type littermates. Interestingly, brain tissue from BAG1 transgenic mice contained higher levels of neuroprotective Hsp70/Hsc70 protein but not mRNA, suggesting a potential mechanism whereby BAG1 exerts its anti-apoptotic effects. In summary, BAG1 displays potent neuroprotective activity in vivo against stroke, and therefore represents an interesting target for developing new therapeutic strategies including gene therapy and small-molecule drugs for reducing brain injury during cerebral ischemia and neurodegenerative diseases.  相似文献   
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目的:研究急性和慢性特发性中心性浆液性脉络膜视网膜病变眼底自发荧光影像模式及眼底荧光血管造影相关性发现。

方法:观察性研究案例。回顾性分析中心性浆液性脉络膜视网膜病变患者临床数据,眼底荧光血管造影及眼底自发荧光影像,并对其调查结果进行比较。

结果:该研究共纳入17例25眼。确诊为急性中心性浆液性脉络膜视网膜病变5眼,慢性疾病或复发性慢性疾病20眼。急性病例眼底自发荧光影像显示低荧光点与荧光血管造影检测出的荧光渗漏点位置相同。慢性特发性中心性浆液性脉络膜视网膜病变眼底荧光血管造影为视网膜色素上皮弥漫性萎缩区域,可透视荧光。眼底自发荧光影像的低荧光区域的形态和位置与眼底荧光血管造影的高荧光区域相对应,然而眼底荧光血管造影的低荧光区域与眼底自发荧光影像的高荧光区域相对应。在急性病例中,低自发荧光点不能准确指出视网膜色素上皮的渗漏点。

结论:中心性浆液性脉络膜视网膜病变眼底自发荧光影像模式能够描述疾病不同阶段的特征,具有无风险和可再生性,可替代荧光素血管造影术治疗中心性浆液性脉络膜视网膜病变。  相似文献   

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HIV seroprevalence in street youth, St. Petersburg, Russia   总被引:1,自引:0,他引:1  
BACKGROUND: Reliable data on HIV infection among Russian street youth are unavailable. The purpose of this study was to assess HIV seroprevalence among street youth in St Petersburg and to describe social, sexual, and behavioral characteristics associated with HIV infection. METHODS: A cross-sectional assessment conducted during January-May 2006 included city-wide mapping of 41 street youth locations, random selection of 22 sites, rapid HIV testing for all consenting 15-19-year-old male and female street youth at these sites, and an interviewer-administered survey. Adjusted odds ratios (AOR) were calculated using logistic regression, accounting for intracluster homogeneity. RESULTS: Of 313 participants, 117 (37.4%, 95% confidence interval 26.1-50.2%) were HIV infected. Subgroups with the highest seroprevalences included double orphans (64.3%), those with no place to live (68.1%), those previously diagnosed with a sexually transmitted infection (STI; 70.5%), those currently sharing needles (86.4%), and those currently using inhalants (60.5%) or injection drugs (78.6%), including Stadol (82.3%) or heroin (78.1%). Characteristics independently associated with HIV infection included injecting drugs (AOR 23.0), sharing needles (AOR 13.3), being a double or single orphan (AOR 3.3 and 1.8), having no place to live (AOR 2.4), and being diagnosed with a STI (AOR 2.1). Most HIV-infected street youth were sexually active (96.6%), had multiple partners (65.0%), and used condoms inconsistently (80.3%). DISCUSSION: Street youth aged 15-19 years in St Petersburg, Russia, have an extraordinarily high HIV seroprevalence. In street youth who are injection drug users, HIV seroprevalence is the highest ever reported for eastern Europe and is among the highest in the world.  相似文献   
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Apoptosis (programmed cell death) plays important roles in many facets of normal mammalian physiology. Host-pathogen interactions have provided evolutionary pressure for apoptosis as a defense mechanism against viruses and microbes, sometimes linking apoptosis mechanisms with inflammatory responses through NFκB induction. Proteins involved in apoptosis and NFκB induction commonly contain evolutionarily conserved domains that can serve as signatures for identification by bioinformatics methods. Using a combination of public (NCBI) and private (RIKEN) databases, we compared the repertoire of apoptosis and NFκB-inducing genes in humans and mice from cDNA/EST/genomic data, focusing on the following domain families: (1) Caspase proteases; (2) Caspase recruitment domains (CARD); (3) Death Domains (DD); (4) Death Effector Domains (DED); (5) BIR domains of Inhibitor of Apoptosis Proteins (IAPs); (6) Bcl-2 homology (BH) domains of Bcl-2 family proteins; (7) Tumor Necrosis Factor (TNF)-family ligands; (8) TNF receptors (TNFR); (9) TIR domains; (10) PAAD (PYRIN; PYD, DAPIN); (11) nucleotide-binding NACHT domains; (12) TRAFs; (13) Hsp70-binding BAG domains; (14) endonuclease-associated CIDE domains; and (15) miscellaneous additional proteins. After excluding redundancy due to alternative splice forms, sequencing errors, and other considerations, we identified cDNAs derived from a total of 227 human genes among these domain families. Orthologous murine genes were found for 219 (96%); in addition, several unique murine genes were found, which appear not to have human orthologs. This mismatch may be due to the still fragmentary information about the mouse genome or genuine differences between mouse and human repertoires of apoptotic genes. With this caveat, we discuss similarities and differences in human and murine genes from these domain families.  相似文献   
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Background: There is a need to identify the follicular dendritic cells (FDC) of the chicken spleen at the ultrastructural level during a secondary immune response. Methods: The cells were identified after intravenous priming BSA and boosting with biotinylated BSA conjugated to colloidal gold particles. Monoclonal antibodies raised specifically either to chicken IgG or IgM were used to characterize these immune complex-trapping cells. Results: The FDC had an irregular morphology which varied through time, supporting the existence of two types of FDC in the chicken spleen, one showing filiform cell processes, the other provided with beaded dendrites. When the filiform dendrites were observed, the FDC bound the antigen on their surfaces. These dendrites showed an intrincate convoluted configuration, forming tightly wrapped networks near the cell body. The networks had the same features as those described in mammals as antigen retaining reticulum (ARR). In chickens, the ARR, which represents sites of antigen localization on FDC, reached maximum development on day 5 after the second injection of BSA and had disappeared by day 8. At this time FDC had beaded dendrites. Conclusions: Antigen is retained on FDC in the chicken spleen for long periods of time. © 1995 Wiley-Liss, Inc.  相似文献   
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