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51.
The structure and organization of the large (L) RNA of iris yellow spot virus (IYSV) was determined, and with this report, the complete genomic sequence of IYSV of the genus Tospovirus, family Bunyaviridae has been elucidated. The L RNA of IYSV was 8,880 nucleotides in length and contained a single open reading frame in the viral complementary (vc) strand. The primary translation product of 331.17 kDa shared many of the features of the viral RNA-dependent RNA polymerase (RdRp) coded by L RNAs of known tospoviruses. The 5′ and 3′ termini of IYSV L RNA (vc) contain two untranslated regions of 33 and 226 nucleotides, respectively, and both termini have conserved terminal nucleotides, another common feature of tospovirus genomic RNAs. Conserved motifs characteristic of RdRps of members of the family Bunyaviridae were present in the IYSV RdRp.  相似文献   
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NF-kappaB activation through B cell receptor (BCR) ligation is critical for B cell development, survival and antigen-mediated activation of B cells. CARD domain and MAGUK-domain containing protein-1 (CARMA1), recently identified adaptor molecule, has been shown to play an essential role in BCR-induced NF-kappaB activation. CARMA1-deficient B cells fail to proliferate upon BCR stimulation, leading to defective humoral responses. Surprisingly, CARMA1-deficient B cells are also defective in CD40-induced proliferation. The mechanisms responsible for CD40-induced proliferation defect have not yet been characterized. In this study, we show that signaling cascades activated by CD40 stimulation are largely unaffected in CARMA1-deficient B cells. Instead, we have found that the defective proliferation of CARMA1-deficient B cells is due to two events. First, CARMA1-deficient B cells show defective cell-cycle progression. Secondly, the numbers of marginal zone (MZ) B cells, which are the main responders upon CD40 stimulation, are greatly diminished in CARMA1-deficient mice. Since B cell maturation requires basal signaling through BCR and NF-kappaB activation, we propose that impaired BCR signaling in CARMA1-deficient mice leads to defective maturation of MZ B cell population, which in turn, contributes to impaired proliferation upon CD40 stimulation.  相似文献   
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Epithelioid glioblastoma (e-gbm) is a recently described variant of glioblastoma (GBM) which is associated with short survival and now added as a provisional entity to WHO 2016 classification of CNStumors. About half of these tumors show characteristic BRAF-V600E mutation. However, unlike conventional GBMs, e-gbm lack specific diagnostic and prognostic markers. Hence, we aimed to molecularly characterize these tumors. An extensive review of literature was performed.In a multi-institutional effort, all the cases of glioblastoma of year 2017 were reviewed. Cases with predominant epithelioid morphology were analysed. Seven cases of e-gbm (adults:4 and pediatric: 3) were identified. Duration of symptoms varied from 2 weeks to one month. Radiologically, all cases were supratentorial, contrast enhancing with solid and cystic appearance. Majority of the cases were immunopositive for GFAP (71%), EMA (71%), S100 (71%) and vimentin (85%). All the cases showed ATRX, INI-1 and H3K27me3 expression. BRAFV600Emutation was seen in 28% of cases. TERT mutation was seen in 40% cases, while one case showed EGFR amplification. H3F3A mutations and PTEN deletions were seen in none. Although e-gbms are rare, epithelioid morphology of a CNS tumor in a young adult or children with areas of necrosis needs thorough histomorphological and genetic workup.  相似文献   
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BACKGROUND: The human sperm-associated antigen 9 (hSPAG9) is of special interest attributing to the findings indicating that SPAG9 is an acrosomal molecule. SPAG9 is not only restricted to acrosomal compartment but also persists in equatorial segment post-acrosome reaction, which is a key location in sperm-egg interaction. METHODS AND RESULTS: Immunogenicity studies in macaques were carried out with recombinant hSPAG9 (rhSPAG9) adsorbed on alum, which resulted in high titres of anti-rhSPAG9 antibodies as determined by enzyme-linked immunosorbent assay (ELISA). Immunoblotting analysis employing anti-rhSPAG9 antibodies generated in monkeys indicated that antibodies specifically reacted with native SPAG9 from macaque and human sperm and rhSPAG9 protein. Furthermore, indirect immunofluorescence experiments demonstrated SPAG9 localization in the acrosomal compartment of macaque and human sperm. In addition, monkey antibodies against rhSPAG9 significantly inhibited the human spermatozoa adherence or penetration in zona-free hamster oocytes. CONCLUSION: These results demonstrate that rhSPAG9 adsorbed on alum is highly immunogenic in subhuman primate model and therefore represents a suitable sperm-based vaccine immunogen for fertility trials in macaque.  相似文献   
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True cysts of the central nervous system (CNS) are rare lesions. A retrospective study of patients with symptomatic non-neoplastic cystic lesions of CNS operated in the Department of Neurosurgery, G.B. Pant Hospital, New Delhi between Jan 1994 and Feb 2001 was conducted. Parasitic cysts, cystic transformation of hemmorhages, vascular malformations and cystic tumours were excluded from the study. A total of 109 cases were reviewed. There were 34, 27, 17, 16, 8, 3 and 2 cases of epidermoid, arachnoid, dermoid, colloid, neurenteric, Rathke's and ependymal cysts and 1 case each of choroid plexus and glial cysts. The clinical presentations, locations, incidence and pathogenesis of these cysts is discussed.  相似文献   
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