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11.
Although bloody pericardial effusion often suggests neoplasia, such an event is not rare in tuberculosis (TB), especially in those countries with a high TB disease burden. Meanwhile, TB accounts for 50% and greater than 90% of large pericardial effusions in human immunodeficiency virus (HIV)-negative and HIV-positive patients, respectively. Here we report a case of a 24-year-old HIV-negative male who presented with fever and hemorrhagic pericardial effusion. The patient was given presumptive anti-TB treatment before diagnosis was established. Eventually the patient responded well to the anti-TB treatment at the last follow-up and the diagnosis was confirmed by aspirated pericardial fluid culture on Lowenstein-Jensen (LJ) medium.  相似文献   
12.
Saccharomyces cerevisiae Rad53, the ortholog of mammalian Chk2, is an essential protein kinase in DNA damage and DNA replication checkpoint pathways. Consecutive phosphatidyl inositol kinase-like kinase (PIKK)-dependent and PIKK-independent steps in activation of Rad53 are key steps for controlling and transmitting diverse downstream responses to DNA damage. However, these activities have not been demonstrated in vitro in defined systems. Here, we have shown that enzymatically dephosphorylated purified Rad53 autoactivates in vitro through a phosphorylation-dependent mechanism. Kinetic analysis demonstrated that autophosphorylation results in a more than 9-fold increase in protein kinase activity. Autophosphorylation was Rad53 concentration-dependent, indicating that the reaction follows an intermolecular mechanism. DNA damage induced oligomerization of a subset of Rad53 molecules in vivo. At low concentrations of Rad53, preincubation of Rad53 with immune complexes containing the Mec1/Ddc2 complex can activate Rad53 kinase activity. Our findings showed that Mec1/Ddc2 complexes can directly activate Rad53 through a phosphorylation-dependent mechanism, and more generally, supported the hypothesis that PIKKs regulate Chk2 orthologs through phosphorylation. Moreover, this work has substantiated a model for PIKK-independent amplification of Rad53 activation (and by extension, activation of other Chk2 orthologs) mediated by inter-Rad53 phosphorylation.  相似文献   
13.
Wheat (Triticum aestivum L.) yellow mosaic virus (WYMV) is transmitted by a fungal vector through soil and causes serious wheat yield losses due to yellow mosaic disease, with yellow-streaked leaves and stunted plants. In the present study, the amplified fragment length polymorphisms (AFLP) and simple sequence repeat (SSR) were used to identify the molecular linkages with the resistance gene against WYMV. Bulked segregant analysis was performed with an F2 population derived from the cross of cultivar Ningmai 9 (resistant) × cultivar Yangmai 10 (susceptible). By screening among the resistant or susceptible parents, the F2 pools and the individuals in the F2 population with 64 combined selective AFLP primers (EcoRI/MseI) or 290 reported SSR primers, a polymorphic DNA segment (approximately 120 bp) was amplified using the primer pair E2/M5, and an SSR marker (approximately 180 bp) was located on wheat chromosome 2A using the primer Xgwm328. Analysis with MAPMAKER/Exp Version 3.0b (Whitehead institute for Biomedical Research, Cambridge, MA, USA) indicated that these two markers were dominantly associated with the resistance gene at distances of 5.4 cM or 17.6 cM, respectively. The resistance gene to WYMV derived from Ningmai 9, is temporarily named YmNM, and was mapped to wheat chromosome 2A.  相似文献   
14.
Cypripedium daliense S. C. Chen et J. L. Wu, a new Species ofOrchidaceae is described with illustrations.  相似文献   
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Zhu YZ  Cai CS  Zhang W  Guo HX  Zhang JP  Ji YY  Ma GY  Wu JL  Li QT  Lu CP  Guo XK 《PloS one》2010,5(11):e13915

Background

Pertussis (whooping cough) caused by Bordetella pertussis (B.p), continues to be a serious public health threat. Vaccination is the most economical and effective strategy for preventing and controlling pertussis. However, few systematic investigations of actual human immune responses to pertussis vaccines have been performed. Therefore, we utilized a combination of two-dimensional electrophoresis (2-DE), immunoblotting, and mass spectrometry to reveal the entire antigenic proteome of whole-cell pertussis vaccine (WCV) targeted by the human immune system as a first step toward evaluating the repertoire of human humoral immune responses against WCV.

Methodology/Principal Findings

Immunoproteomic profiling of total membrane enriched proteins and extracellular proteins of Chinese WCV strain 58003 identified a total of 30 immunoreactive proteins. Seven are known pertussis antigens including Pertactin, Serum resistance protein, chaperonin GroEL and two OMP porins. Sixteen have been documented to be immunogenic in other pathogens but not in B.p, and the immunogenicity of the last seven proteins was found for the first time. Furthermore, by comparison of the human and murine immunoproteomes of B.p, with the exception of four human immunoreactive proteins that were also reactive with mouse immune sera, a unique group of antigens including more than 20 novel immunoreactive proteins that uniquely reacted with human immune serum was confirmed.

Conclusions/Significance

This study is the first time that the repertoire of human serum antibody responses against WCV was comprehensively investigated, and a small number of previously unidentified antigens of WCV were also found by means of the classic immunoproteomic strategy. Further research on these newly identified predominant antigens of B.p exclusively against humans will not only remarkably accelerate the development of diagnostic biomarkers and subunit vaccines but also provide detailed insight into human immunity mechanisms against WCV. In particular, this work highlights the heterogeneity of the B.p immunoreactivity patterns of the mouse model and the human host.  相似文献   
18.
由于人为采集、走私贩卖以及生境的破坏,分布于中国西南石灰岩地区的野生硬叶兜兰居群受到严重的干扰与威胁。为有效地保护这种珍稀野生植物,本研究采用ISSR和SRAP两种分子标记对15个硬叶兜兰野生居群进行遗传多样性及遗传结构的研究。结果表明,硬叶兜兰在物种水平上具有较高的遗传多样性(ISSR:PPB=91.66%,He=0.3839;SRAP:PPB=99.29%,Hc=0.2806)。硬叶兜兰居群间存在一定程度的遗传分化(ISSR:Gs1: 0.2577;SRAP:Gst=0.2383),可能由于较低的基因流(ISSR:Nm=0.7201;SRAP:Nm=0.7991)所致。UPGMA聚类分析以及主成分分析均把15个居群分成2个主要分支。居群间的地理距离和海拔差距是引起居群遗传分化的自然因素。  相似文献   
19.
Tropomyosins are actin-binding cytoskeletal proteins that play a pivotal role in regulating the function of actin filaments in muscle and non-muscle cells; however, the roles of non-muscle tropomyosins in mouse oocytes are unknown. This study investigated the expression and functions of non-muscle tropomyosin (Tpm3) during meiotic maturation of mouse oocytes. Tpm3 mRNA was detected at all developmental stages in mouse oocytes. Tpm3 protein was localized at the cortex during the germinal vesicle and germinal vesicle breakdown stages. However, the overall fluorescence intensity of Tpm3 immunostaining was markedly decreased in metaphase II oocytes. Knockdown of Tpm3 impaired asymmetric division of oocytes and spindle migration, considerably reduced the amount of cortical actin, and caused membrane blebbing during cytokinesis. Expression of a constitutively active cofilin mutant and Tpm3 overexpression confirmed that Tpm3 protects cortical actin from depolymerization by cofilin. The data indicate that Tpm3 plays crucial roles in maintaining cortical actin integrity and asymmetric cell division during oocyte maturation, and that dynamic regulation of cortical actin by Tpm3 is critical to ensure proper polar body protrusion.  相似文献   
20.
Repair of chromosome double-strand breaks (DSBs) is central to cell survival and genome integrity. Nonhomologous end joining (NHEJ) is the major cellular repair pathway that eliminates chromosome DSBs. Here we report our genetic screen that identified Rsc8 and Rsc30, subunits of the Saccharomyces cerevisiae chromatin remodeling complex RSC, as novel NHEJ factors. Deletion of RSC30 gene or the C-terminal truncation of RSC8 impairs NHEJ of a chromosome DSB created by HO endonuclease in vivo. rsc30Delta maintains a robust level of homologous recombination and the damage-induced cell cycle checkpoints. By chromatin immunoprecipitation, we show recruitment of RSC to a chromosome DSB with kinetics congruent with its involvement in NHEJ. Recruitment of RSC to a DSB depends on Mre11, Rsc30, and yKu70 proteins. Rsc1p and Rsc2p, two other RSC subunits, physically interact with yKu80p and Mre11p. The interaction of Rsc1p with Mre11p appears to be vital for survival from genotoxic stress. These results suggest that chromatin remodeling by RSC is important for NHEJ.  相似文献   
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