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细胞焦亡与牙龈卟啉单胞菌的关系及其在牙周病发生发展中的作用机制
Mechanism of pyroptosis and Porphyromonas gingivalis in periodontitis development process
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唐秋玲,李格格,潘佳慧,侯玉帛,孟阳,于维先
- , 2017, DOI: 10.7518/gjkq.2017.06.007
Abstract: 摘要: 细胞焦亡是一种典型的程序性细胞死亡方式,主要通过炎症小体的介导,并伴有大量促炎性细胞因子的释放。牙龈卟啉单胞菌作为牙周炎的关键致病菌,一方面可通过激活牙周组织中巨噬细胞内核苷酸结合寡聚化结构域样受体蛋白3炎症小体,促进细胞焦亡,引发牙周组织免疫病理损伤;另一方面,牙龈卟啉单胞菌通过抑制血管内皮细胞焦亡,逃逸免疫系统的杀伤作用,促进自身生存。本文就细胞焦亡及其在牙周炎中的作用机制作一综述。
Abstract: Pyroptosis is a typical form of programmed cell death mediated by inflammasomes. It leads to inflammatory response through the release of pro-inflammatory cytokines. Porphyromonas gingivalis is the keystone pathogen of periodontitis. On the one hand, it can activate thenucleotide-binding oligomerization domain like receptor protein 3 inflammasomes of macrophages in the periodontal tissue, and it also can promote pyroptosis that lead to the immune pathological damage of periodontal tissue; on the other hand, it restrain the pyroptosis of vascular endothelial cell and escape the killing of the immune system. In this paper, the recent progress and mechanism of pyroptosis in periodontitis are reviewed.
中图分类号
Genetic diversity of Streptococcus suis isolates as determined by comparative genome hybridization
Astrid de Greeff, Henk J Wisselink, Freddy M de Bree, Constance Schultsz, Christoph G Baums, Hoa Thi, Norbert Stockhofe-Zurwieden, Hilde E Smith
BMC Microbiology , 2011, DOI: 10.1186/1471-2180-11-161
Abstract: In this study, the correlation between gene content, serotype, phenotype and virulence among 55 S. suis strains was studied using Comparative Genome Hybridization (CGH). Clustering of CGH data divided S. suis isolates into two clusters, A and B. Cluster A isolates could be discriminated from cluster B isolates based on the protein expression of extracellular factor (EF). Cluster A contained serotype 1 and 2 isolates that were correlated with virulence. Cluster B mainly contained serotype 7 and 9 isolates. Genetic similarity was observed between serotype 7 and serotype 2 isolates that do not express muramidase released protein (MRP) and EF (MRP-EF-), suggesting these isolates originated from a common founder. Profiles of 25 putative virulence-associated genes of S. suis were determined among the 55 isolates. Presence of all 25 genes was shown for cluster A isolates, whereas cluster B isolates lacked one or more putative virulence genes. Divergence of S. suis isolates was further studied based on the presence of 39 regions of difference. Conservation of genes was evaluated by the definition of a core genome that contained 78% of all ORFs in P1/7.In conclusion, we show that CGH is a valuable method to study distribution of genes or gene clusters among isolates in detail, yielding information on genetic similarity, and virulence traits of S. suis isolates.Streptococcus suis forms a problem in the swine industry. Clinically healthy sows carry S. suis in their nasal cavities and on their tonsils, and transmit the bacteria to their piglets [1], that develop a variety of infections, such as septicaemia, meningitis, polyarthritis, and endocarditis, and often do not survive [2]. S. suis occasionally causes meningitis, arthritis or endocarditis in humans. However, recently several large human outbreaks of S. suis have been described in China [3,4], and Thailand [5], whilst S. suis meningitis has become endemic in Vietnam [6,7], suggesting that isolates that are more virulent t
论宋亡“诗史”  [PDF]
方勇
浙江大学学报(人文社会科学版) , 2001,
Abstract: ?宋末士子在经历了空前的鼎革动乱之后,对杜甫“诗史”精神有了比唐人更为深刻的认识。而在艺术形式方面,他们对杜甫“诗史”又有了重大的突破和发展。尤其是汪元量主要用联章组诗手法创作出来的宋亡“诗史”长卷,舒岳祥主要用以序代题手法创作出来的反映宋末元初东南沿海地区动乱现实的“诗史”巨卷,则更成了我国“诗史”发展史上的两座里程碑。
Molecular Basis of Resistance to Muramidase and Cationic Antimicrobial Peptide Activity of Lysozyme in Staphylococci  [PDF]
Silvia Herbert,Agnieszka Bera,Christiane Nerz,Dirk Kraus,Andreas Peschel,Christiane Goerke,Michael Meehl,Ambrose Cheung,Friedrich G?tz
PLOS Pathogens , 2007, DOI: 10.1371/journal.ppat.0030102
Abstract: It has been shown recently that modification of peptidoglycan by O-acetylation renders pathogenic staphylococci resistant to the muramidase activity of lysozyme. Here, we show that a Staphylococcus aureus double mutant defective in O-acetyltransferase A (OatA), and the glycopeptide resistance-associated two-component system, GraRS, is much more sensitive to lysozyme than S. aureus with the oatA mutation alone. The graRS single mutant was resistant to the muramidase activity of lysozyme, but was sensitive to cationic antimicrobial peptides (CAMPs) such as the human lysozyme-derived peptide 107R-A-W-V-A-W-R-N-R115 (LP9), polymyxin B, or gallidermin. A comparative transcriptome analysis of wild type and the graRS mutant revealed that GraRS controls 248 genes. It up-regulates global regulators (rot, sarS, or mgrA), various colonization factors, and exotoxin-encoding genes, as well as the ica and dlt operons. A pronounced decrease in the expression of the latter two operons explains why the graRS mutant is also biofilm-negative. The decrease of the dlt transcript in the graRS mutant correlates with a 46.7% decrease in the content of esterified d-alanyl groups in teichoic acids. The oatA/dltA double mutant showed the highest sensitivity to lysozyme; this mutant completely lacks teichoic acid–bound d-alanine esters, which are responsible for the increased susceptibility to CAMPs and peptidoglycan O-acetylation. Our results demonstrate that resistance to lysozyme can be dissected into genes mediating resistance to its muramidase activity (oatA) and genes mediating resistance to CAMPs (graRS and dlt). The two lysozyme activities act synergistically, as the oatA/dltA or oatA/graRS double mutants are much more susceptible to lysozyme than each of the single mutants.
《史记》亡缺研究述评  [PDF]
李景文,宋立
图书情报工作 , 2009,
Abstract: ?针对两千年来历代学者对《史记》亡佚情况进行考辨的情况,分类梳理历代学者的研究结果,将其归纳为“十篇全亡说”、“部分亡佚说”、“十篇未亡说”三大类进行述评,并提出今后研究应当关注的方向。
Pre-Absorbed Immunoproteomics: A Novel Method for the Detection of Streptococcus suis Surface Proteins  [PDF]
Wei Zhang, Guangjin Liu, Fang Tang, Jing Shao, Yan Lu, Yinli Bao, Huochun Yao, Chengping Lu
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0021234
Abstract: Streptococcus suis serotype 2 (SS2) is a zoonotic pathogen that can cause infections in pigs and humans. Bacterial surface proteins are often investigated as potential vaccine candidates and biomarkers of virulence. In this study, a novel method for identifying bacterial surface proteins is presented, which combines immunoproteomic and immunoserologic techniques. Critical to the success of this new method is an improved procedure for generating two-dimensional electrophoresis gel profiles of S. suis proteins. The S. suis surface proteins identified in this study include muramidase-released protein precursor (MRP) and an ABC transporter protein, while MRP is thought to be one of the main virulence factors in SS2 located on the bacterial surface. Herein, we demonstrate that the ABC transporter protein can bind to HEp-2 cells, which strongly suggests that this protein is located on the bacterial cell surface and may be involved in pathogenesis. An immunofluorescence assay confirmed that the ABC transporter is localized to the bacterial outer surface. This new method may prove to be a useful tool for identifying surface proteins, and aid in the development of new vaccine subunits and disease diagnostics.
Acute meningitis by Streptococcus suis
Maria-Jesus Corrales-Arroyo,Maria Angeles Del Real-Francia,Amalia Hernandez-Gonzalez,Jose Manuel Morales Puebla
Journal of Microbiology and Infectious Diseases , 2012,
Abstract: Streptococcus suis is a coccus Gram positive, anaerobic optional. Human infection by this microorganism is a zoonoticdisease that usually presents as purulent meningitis. Mortality is low but is common sequelae. A case of meningitis byS. suis secondary to contact with pigs is presented here. A 35-year-old male patient was admitted to the hospital complainingof high fever, malaise, vomiting and headache. A physical examination revealed decreased level of consciousness,with adequate response to painful stimulus and his eyes with deconjugated gaze. S. suis was isolated in bloodculture. He was treated with cefotaxime, vancomycin and acyclovir in the intensive care unit. He experienced progressiveimprovement. He was discharged with severe deafness and a minimally unstable gait as sequellae. J Microbiol Infect Dis2012; 2(4): 160-162Key words: Streptococcus suis, meningitis, deafness.
Meningitis por Streptococcus suis
Geffner Sclarsky,D. E.; Moreno Mu?oz,R.; Campillo Alpera,Ma.S.; Pardo Serrano,F.J.; Gómez Gómez,A.; Martínez-Lozano,Ma.D.;
Anales de Medicina Interna , 2001, DOI: 10.4321/S0212-71992001000600007
Abstract: human infection by streptococcus suis (s. suis) is a zoonosis, with a known occupational risk and clinical presentation mainly as a purulent meningitis with low mortality and frequent hearing loss and ataxia sequela. less than 150 human cases have been reported since original one thirty years ago. there is a geographical distribution most patients living in northen europe and south asia. s. suis disease in human has been reported in two patients in spain the last years. we present two patients with s. suis meningitis, both were men with occupation related by pork meet, and good outcome. they come at our hospital in a lapse of one month. both had neurosensorial hearing loss and walking ataxia. one patient had peripheral facial paralysis and diplopia because of paresia of contralateral sixth nerve, with complete resolution at three months.the rare presentation of s. suis meningitis in our country must not forget us to record the working risk at anamnesis.
Correlation between PFGE Groups and mrp/epf/sly Genotypes of Human Streptococcus suis Serotype 2 in Northern Thailand  [PDF]
Prasit Tharavichitkul,Kanreuthai Wongsawan,Naoki Takenami,Sumalee Pruksakorn,Achara Fongcom,Marcelo Gottschalk,Banyong Khanthawa,Volaluk Supajatura,Shinji Takai
Journal of Pathogens , 2014, DOI: 10.1155/2014/350416
Abstract: Streptococcus suis infection is a severe zoonotic disease commonly found in Northern Thailand where people often consume raw pork and/or pig’s blood. The most frequent clinical presentations are meningitis, sepsis, and endocarditis with higher rate of mortality and hearing loss sequelae. To clarify the correlation between pulsed-field gel electrophoresis (PFGE) groups and mrp/epf/sly genotypes of S. suis serotype 2, 62 patient and 4 healthy pig isolates from Northern Thailand were studied. By PFGE analysis, at 66% homology, most human isolates (69.4%) and 1 pig isolate were in group A, whereas 14.5% of human isolates and 3 out of 4 pig isolates were in group D. According to mrp/epf/sly genotypes, 80.6% of human isolates were identified in mrp+epf?sly? and only 12.9% were in mrp?epf?sly+ genotypes; in contrast, 1 and 3 pig isolates were detected in these two genotypes, respectively. Interestingly, all isolates of S. suis serotype 2 classified in PFGE groups A, B, and E were set in mrp+epf?sly? genotypes. These data show a close correlation between PFGE groups and mrp/epf/sly genotypes of human S. suis serotype 2. 1. Introduction Streptococcus suis, recognized as a significant swine and human pathogen, mainly causes meningitis, sepsis, endocarditis, and septic shock [1]. It can be transmitted to humans by contact with sick or carrier pigs, pig-derived products [2], or eating undercooked pork [3, 4]. Capsular polysaccharide (CPS) is the most important proven critical virulence factor, due to its antiphagocytosis activity [5]. Of 35 serotypes, serotype 2 is the most frequently isolated and associated with disease in both animals and humans [6]. In addition, virulence-related proteins, such as muramidase-released protein (MRP), extracellular factor (EF), and hemolysin (suilysin, SLY), are expressed by some strains of S. sui “as discussed by Gottschalk and Segura [1].” These proteins are encoded by the genes mrp, epf, and sly, respectively. MRP/EF/SLY phenotypes or mrp/epf/sly genotypes of S. suis serotype 2 have been studied mostly in pig isolates with very little data for human isolates [1, 7], especially in Northern Thailand. Pulsed-field gel electrophoresis (PFGE) of DNA restricted with SmaI has been confirmed to be valuable for evaluating the genetic diversity of S. suis [8]. The present study aims to clarify the correlation between PFGE and mrp/epf/sly genotypes of S. suis serotype 2 isolated from patients in Northern Thailand. 2. Materials and Methods 2.1. S. suis Serotype 2 Strains from Humans and Healthy Pigs A total of 66 S. suis serotype 2 (SS2)
猪种、牛种、羊种、绵羊种布鲁菌多重PCR检测方法的建立及应用
Foundation and Initial Application of Multiplex PCR Method for Detecting B.suis, B.abortus, B.melitensis and B.ovis Infection
 [PDF]

何亚鹏,许信刚,付明哲,,
- , 2017, DOI: 10.7606/j.issn.1004-1389.2017.08.005
Abstract: 为建立在临床样本能够同时检测猪种、牛种、羊种、绵羊种布鲁菌的多重PCR方法,根据NCBI已收录的布鲁菌全基因,设计并合成4对特异性引物,通过优化多重PCR的反应条件,建立能够同时检测4种布鲁菌的多重PCR诊断方法。特异性试验结果表明,可以从4种布鲁菌以及 4 种细菌混合物中扩增出大小分别为276、494、733和976 bp的特异性条带,对照组的检测结果为阴性;敏感性试验结果表明,对4种病原菌基因组DNA的检出量为猪种32.2 pg、牛种21.3 pg、羊种27.5 pg、绵羊种43.2 pg;人工模拟感染样本检测结果表明,能从混合感染的病料中特异地检测出 4 种病原菌。应用该方法对 200 份临床奶山羊乳样进行检测,结果检出4份阳性。建立的多重PCR方法具有特异性强、敏感度高、稳定性好的特点,可以有效地检测 4 种布鲁菌的感染。
In order to develop multiplex PCR assay for clinical detection of B.suis, B.abortus, B.melitensis and B.ovis infection, four pairs of primers were designed and synthesized based on highly conserved regions of B.suis, B.abortus, B.melitensis and B.ovis genome sequence in Genbank. The multiplex PCR reaction condition was optimized and multiplex PCR method for detecting B.suis, B.abortus, B.melitensis and B.ovis infection was established. The specificity test showed that fragments of 276 bp, 494 bp, 733 bp and 976 bp were amplified from genomic DNA of B.suis, B.abortus, B.melitensis and B.ovis,respectively. No amplification was achieved from control groups of other bacteria. The sensitivity test showed that the multiplex PCR could detect genome DNA of 21.3 pg for B.abortus, 27.5 pg for B.melitensis, 43.2 pg for B.ovis and 32.2 pg for B.suis. The artificial simulation test showed that the multiplex PCR could detect four kinds of pathogens from co-infection disease material. The initial application test showed 200 clinical goat’s milk samples were subjected to PCR. Among 4 clinical samples were B.melitensis-positive. The result indicated the multiplex PCR method had advantages of specificity, sensitivity, repetition, and it could effectively detect the infection of B.suis, B.abortus, B.melitensis and B.ovis in clinical samples.
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