Microbial pathogenesis
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Microbial pathogenesis · Sep 2015
Meta AnalysisAssociation between the IL1B -31C > T polymorphism and Helicobacter pylori infection in Asian and Latin American population: A meta-analysis.
Host genetic factors that control the production of cytokines, including interleukin-1β (IL-1β), possibly affect susceptibility to many Helicobacter pylori-related diseases. There is a complex interplay between H. pylori infection, the subsequent production of certain cytokines, and H. pylori-related diseases. We conducted a meta-analysis to clarify the association between the IL1B -31C > T polymorphism and H. pylori infection, and possible subsequent pathogenic mechanisms. ⋯ Our meta-analysis demonstrated that IL1B -31C > T polymorphism might increase H. pylori infection risk in Asian and Latin American population. Further studies with different ethnicities and larger sample size are required to validate this result.
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Microbial pathogenesis · Dec 2014
Tongue images and tongue coating microbiome in patients with colorectal cancer.
Tongue diagnosis, as a unique method of traditional Chinese medicine (TCM), discriminates physiological functions and pathological conditions by observing the changes of the tongue coating. ⋯ Tongue diagnosis may provide important leads towards novel microbiome-related diagnostic tools and tongue coating microbiome may be a novel biomarker for characterizing patient with colorectal cancer.
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Microbial pathogenesis · Sep 2014
Aspirin is an efficient inhibitor of quorum sensing, virulence and toxins in Pseudomonas aeruginosa.
Quorum sensing (QS) plays a vital role in regulation of virulence factors and toxins in Pseudomonas aeruginosa, which can cause serious human infections. Therefore, the QS system in P. aeruginosa may be an important target for pharmacological intervention. Activity of aspirin on the QS system was assessed using a reporter strain assay and confirmed using RT-PCR to test expression of virulence factors and toxins. ⋯ The molecular modeling analysis suggests the QS inhibitory action of aspirin occurs through interaction of aspirin's aryl group and Tyr-88 of the LasR receptor, by strong π-π stacking interactions, which associated with a conformational change of the receptor-aspirin complex. The inhibitory effect of aspirin on virulence factors was specific to P. aeruginosa as aspirin at sub-MIC did not affect the biofilm or motility of Escherichia coli. To summarize, the collective data demonstrate that low concentrations of aspirin inhibit quorum sensing of P. aeruginosa.
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Microbial pathogenesis · Apr 2014
Recombinant BCG coexpressing Ag85B, ESAT-6 and Rv3620c elicits specific Th1 immune responses in C57BL/6 mice.
Tuberculosis (TB) remains to be an enormous global health problem. The inconsistent protection efficacy of Bacille Calmette-Guérin (BCG) calls for new vaccines for TB. One choice to improve the efficacy of BCG vaccine is recombinant BCG (rBCG). ⋯ Moreover, this rBCG induced a strong humoral response in mice with an increasing antigen-specific IgG titer. Therefore, we concluded that this rBCG could significantly increase both Th1 type cellular immune response and antigen-specific humoral response compared with BCG. The above observations demonstrated that rBCG::Ag85B-ESAT6-Rv3620c is a potential candidate vaccine against M. tuberculosis for further study.
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Microbial pathogenesis · Dec 2011
Absence of phagocyte NADPH oxidase 2 leads to severe inflammatory response in lungs of mice infected with Coccidioides.
Production of reactive oxygen species (ROS) resulting from phagocytic NADPH oxidase (NOX2) activity has been reported to contribute to host defense against numerous microbial pathogens. In this study we explored the role of NOX2 production in experimental coccidioidomycosis, a human respiratory disease caused by a soil-borne fungal pathogen. Activated and non-activated macrophages isolated from either NOX2(-/-) knock-out or wild type (WT) mice showed comparable ROS production and killing efficiency in vitro when infected with parasitic cells of Coccidioides. ⋯ These combined results initially suggested that NOX2 activity and ROS production are not essential for protection against Coccidioides infection. However, the reduced survival of non-vaccinated NOX2(-/-) mice correlated with high, sustained numbers of lung-infiltrated neutrophils on days 7 and 11 postchallenge, an expansion of the regulatory T cell population in infected lungs in the knock-out mice, and elevated concentrations of pro-inflammatory cytokines and chemokines in lung homogenates compared to infected WT mice. Although NOX2-derived ROS appeared to be dispensable for both innate and acquired immunity to pulmonary Coccidioides infection, evidence is presented that NOX2 production plays a role in limiting pathogenic inflammation in this murine model of coccidioidomycosis.