34 research outputs found
Purification and characterization of nisin P produced by a strain of Streptococcus gallolyticus
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Detection of Borrelia-specific 16S rRNA sequence in total RNA extracted from Ixodes ricinus ticks
A reverse transcriptase - polymerase chain reaction based assay for Borrelia species detection in ticks was developed. The method was based on amplification of 552 nucleotide bases long sequence of 16S rRNA, targeted by Borrelia specific primers. In the present study, total RNA extracted from Ixodes ricinus ticks was used as template. The results showed higher sensitivity for Borrelia detection as compared to standard dark-field microscopy. Method specificity was confirmed by cloning and sequencing of obtained 552 base pairs long amplicons. Phylogenetic analysis of obtained sequences showed that they belong to B. lusitaniae and B. afzelii genospecies. RT-PCR based method presented in this paper could be very useful as a screening test for detecting pathogen presence, especially when in investigations is required extraction of total RNA from ticks
Caspase-3 Mediates the Pathogenic Effect of \u3cem\u3e Yersinia pestis \u3c/em\u3e YopM in Liver of C57BL/6 Mice and Contributes to YopM\u27s Function in Spleen
The virulence protein YopM of the plague bacterium Yersinia pestis has different dominant effects in liver and spleen. Previous studies focused on spleen, where YopM inhibits accumulation of inflammatory dendritic cells. In the present study we focused on liver, where PMN function may be directly undermined by YopM without changes in inflammatory cell numbers in the initial days of infection, and foci of inflammation are easily identified. Mice were infected with parent and ΔyopM-1 Y. pestis KIM5, and effects of YopM were assessed by immunohistochemistry and determinations of bacterial viable numbers in organs. The bacteria were found associated with myeloid cells in foci of inflammation and in liver sinusoids. A new in-vivo phenotype of YopM was revealed: death of inflammatory cells, evidenced by TUNEL staining beginning at d 1 of infection. Based on distributions of Ly6G+, F4/80+, and iNOS+ cells within foci, the cells that were killed could have included both PMNs and macrophages. By 2 d post-infection, YopM had no effect on distribution of these cells, but by 3 d cellular decomposition had outstripped acute inflammation in foci due to parent Y. pestis, while foci due to the Δ-1yopM strain still contained many inflammatory cells. The destruction depended on the presence of both PMNs in the mice and YopM in the bacteria. In mice that lacked the apoptosis mediator caspase-3 the infection dynamics were novel: the parent Y. pestis was limited in growth comparably to the ΔyopM-1 strain in liver, and in spleen a partial growth limitation for parent Y. pestis was seen. This result identified caspase-3 as a co-factor or effector in YopM\u27s action and supports the hypothesis that in liver YopM\u27s main pathogenic effect is mediated by caspase-3 to cause apoptosis of PMNs
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Interlaboratory comparison of a multiplex immunoassay that measures human serum IgG antibodies against six-group B streptococcus polysaccharides.
Measurement of IgG antibodies against group B streptococcus (GBS) capsular polysaccharide (CPS) by use of a standardized and internationally accepted multiplex immunoassay is important for the evaluation of candidate maternal GBS vaccines in order to compare results across studies. A standardized assay is also required if serocorrelates of protection against invasive GBS disease are to be established in infant sera for the six predominant GBS serotypes since it would permit the comparison of results across the six serotypes. We undertook an interlaboratory study across five laboratories that used standardized assay reagents and protocols with a panel of 44 human sera to measure IgG antibodies against GBS CPS serotypes Ia, Ib, II, III, IV, and V. The within-laboratory intermediate precision, which included factors like the lot of coated beads, laboratory analyst, and day, was generally below 20% relative standard deviation (RSD) for all six serotypes, across all five laboratories. The cross-laboratory reproducibility was < 25% RSD for all six serotypes, which demonstrated the consistency of results across the different laboratories. Additionally, anti-CPS IgG concentrations for the 44-member human serum panel were established. The results of this study showed assay robustness and that the resultant anti-CPS IgG concentrations were reproducible across laboratories for the six GBS CPS serotypes when the standardized assay was used
Long Lamai community ICT4D E‐commerce system modelling: an agent oriented role‐based approach
This paper presents the post‐mortem report upon completion of the Long Lamai e‐commerce development project. Some weaknesses with regards to the current software modelling approach are identified and an alternative role‐based approach is proposed. We argue that the existing software modelling technique is not suitable for modelling, making it difficult to establish a good contract between stakeholders causing delays in the project delivery. The role‐based approach is able to explicitly highlight the responsibilities among stakeholders, while also forming the contract agreement among them leading towards sustainable ICT4D
Effects of Ibuprofen on the physiology and outcome of rabbit endotoxic shock
Background: Despite major developments in the management of septic shock, the mortality rate had progressively increased. Ibuprofen has been shown to have beneficial physiological effects when used as a treatment. However, there are conflicting results with respect to survival. This study aims to investigate the effect of ibuprofen on vital functions, various physiological parameters and survival during endotoxic shock in rabbits
Evaluation the oral hygiene conditions, oral Candida colonization and salivary Streptococcus mutans and Lactobacilli density in a group of β-thalassemic children and adolescence
Role of the Yersinia pestis Ail Protein in Preventing a Protective Polymorphonuclear Leukocyte Response during Bubonic Plague▿
The ability of Yersinia pestis to forestall the mammalian innate immune response is a fundamental aspect of plague pathogenesis. In this study, we examined the effect of Ail, a 17-kDa outer membrane protein that protects Y. pestis against complement-mediated lysis, on bubonic plague pathogenesis in mice and rats. The Y. pestis ail mutant was attenuated for virulence in both rodent models. The attenuation was greater in rats than in mice, which correlates with the ability of normal rat serum, but not mouse serum, to kill ail-negative Y. pestis in vitro. Intradermal infection with the ail mutant resulted in an atypical, subacute form of bubonic plague associated with extensive recruitment of polymorphonuclear leukocytes (PMN or neutrophils) to the site of infection in the draining lymph node and the formation of large purulent abscesses that contained the bacteria. Systemic spread and mortality were greatly attenuated, however, and a productive adaptive immune response was generated after high-dose challenge, as evidenced by high serum antibody levels against Y. pestis F1 antigen. The Y. pestis Ail protein is an important bubonic plague virulence factor that inhibits the innate immune response, in particular the recruitment of a protective PMN response to the infected lymph node
Predictors of outcome in patients with tuberculous meningitis
OBJECTIVE: To assess predictors of mortality and neurological sequelae in patients with tuberculous meningitis (TBM)
Tuberculous meningits in adults in Turkey: Epidemiology, diagnosis, clinic and laboratory
A retrospective study was performed to assess the epidemiology, diagnosis, clinic, and laboratory of the patients with tuberculous meningitis (TBM) in a multicentral study. The medical records of adult cases with TBM treated at 12 university hospitals throughout Turkey, between 1985 and 1998 were reviewed using a standardized protocol. The diagnosis of TMB was established with the clinical and laboratory findings and/or microbiological confirmation in cerebrospinal fluid (CSF). The non-microbiologically confirmed cases were diagnosed with five diagnostic sub-criteria which CSF findings, radiological findings, extra-neural tuberculosis, epidemiological findings and response to antituberculous therapy. A total of 469 patients were included in this study. Majority of the patients were from Southeast Anatolia (164 patients, 35.0%) and (108 patients, 23.0%) from East Anatolia regions. There was a close contact with a tuberculous patient in 88 of 341 patients (25.8%) and with a tuberculous family member in 53 of 288 patients (18.4%). BCG scar was positive in 161 of 392 patients (41.1%). Tuberculin skin test was done in 233 patients and was found to be negative in 75. Totally 115 patients died (24.5%) of whom 23 died in 24 hour after admittance. The diagnosis was confirmed with clinical findings and CSF culture and/or Ziehl-Nelson staining in 88 patients (18.8%). Besides clinical criteria, there were three or more diagnostic sub-criteria in 252 cases (53.7%), two diagnostic sub-criteria in 99 cases (21.1%), and any diagnostic sub-criteria in 30 patients (6.4%). Since TBM is a very critical disease, early diagnosis and treatment may reduce fatal outcome and morbidity