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BackgroundHelicobacter pylori, a lifelong and typically asymptomatic infection of the stomach, profoundly alters gastric immune responses, and may benefit the host in protection against other pathogens. We explored the hypothesis that H. pylori contributes to the control of infection with Mycobacterium tuberculosis.Methodology/principal findingsWe first examined M. tuberculosis-specific IFN-gamma and H. pylori antibody responses in 339 healthy Northern Californians undergoing routine tuberculin skin testing. Of 97 subjects (29%) meeting criteria for latent tuberculosis (TB) infection (LTBI), 45 (46%) were H. pylori seropositive. Subjects with LTBI who were H. pylori-seropositive had 1.5-fold higher TB antigen-induced IFN-gamma responses (p = 0.04, ANOVA), and a more Th-1 like cytokine profile in peripheral blood mononuclear cells, compared to those who were H. pylori seronegative. To explore an association between H. pylori infection and clinical outcome of TB exposure, we evaluated H. pylori seroprevalence in baseline samples from two high risk TB case-contact cohorts, and from cynomolgus macaques experimentally challenged with M. tuberculosis. Compared to 513 household contacts who did not progress to active disease during a median 24 months follow-up, 120 prevalent TB cases were significantly less likely to be H. pylori infected (AOR: 0.55, 95% CI 0.0.36-0.83, p = 0.005), though seroprevalence was not significantly different from non-progressors in 37 incident TB cases (AOR: 1.35 [95% CI 0.63-2.9] p = 0.44). Cynomolgus macaques with natural H. pylori infection were significantly less likely to progress to TB 6 to 8 months after M. tuberculosis challenge (RR: 0.31 [95% CI 0.12-0.80], p = 0.04).Conclusions/significanceH. pylori infection may induce bystander effects that modify the risk of active TB in humans and non-human primates. That immunity to TB may be enhanced by exposure to other microbial agents may have important implications for vaccine development and disease control.

Background: Short-acting β2-agonists (SABA), the most potent and rapid-acting relievers are commonly used to provide quick relief of asthma symptoms. However, there is an increasing concern regarding the misuse of SABA medicines. Objective: This qualitative systematic review aims to determine, evaluate, and summarize the perceptions, attitudes, and behaviors towards the use of SABA from the patients' perspectives. Methods: The databases searched included PubMed, Scopus, PsycINFO, CINAHL, and Cochrane database. Original research articles reporting the perceptions, attitudes, or behaviors of asthma patients towards the use of SABA, which was available as full text, published in the English language between the year 2000 and February 2023 were included in the review. Commentaries, letters to editor, review articles, and conference proceedings were excluded. Results: A total of five articles were included. Six overarching themes were obtained: (1) perceptions on health status; (2) perceptions and attitudes towards the impact of asthma; (3) perceptions towards asthma control; (4) perceptions towards asthma knowledge; (5) risk perceptions; (6) perceptions, attitudes, and behaviors towards the use of SABA. Conclusion: Despite the fact that SABA could rapidly alleviate asthma symptoms, SABA over-users were less likely to describe their health status and asthma control as 'excellent'. Most SABA over-users did not know that frequent SABA usage would worsen their asthma control, and they exhibited psychological linkage towards the use of SABA. Collaborative efforts between policymakers, healthcare professionals and patients are warranted to reconstruct SABA prescribing practice and usage. [ABSTRACT FROM AUTHOR]

Background Mycobacterium tuberculosis infects nearly 1/3 of the world population and this reservoir forms the largest pool from which new cases arise. Among the cytokines, IFN-γ is a key determinant in protection against tuberculosis. Single nucleotide polymorphisms (SNPs) in IFN-γ gene (+874 T/A) which determine TT high (hi), AA low (lo) and TA intermediate (int) responder phenotypes have shown variable associations with tuberculosis disease outcome in different ethnic populations. The objective of the current study was to analyze IFN-γ gene combinations with other IFN-γ regulating cytokine genes (IL-10, TNF -α, IL-6) to see the effect of gene- combinations on disease severity outcome in pulmonary tuberculosis. Methods and Findings Study groups comprised of pulmonary TB patients stratified according to lung tissue involvement into mild (Pmd = 74) or advance (Pad = 23) lung disease and compared with healthy controls (TBNA = 166). Genotype analysis was carried out using amplification refractory mutation system-PCR (ARMS-PCR). IFN-γ gene (+874 T/A) functional SNP combinations in TNFα (-308 G/A), IL-10 (-1082 A/G) and IL-6 (-174 G/C) were analyzed. Single gene analysis (Pearson Χ2) showed a dominant association of IFN-γ TT hi genotype (p = 0.001) and T allele (p = 0.001) with mild disease. IFN-γlo -IL-10lo genotype combination was associated with advanced disease (p = 0.002). IFN-γhi -IL-6 hi combination was associated with mild disease (p = 0.0005) while IFN-γlo -IL-6 int was associated with protection against both forms of pulmonary disease (p = 0.002). Conclusion Our results show that a limited number of IFN-γ gene combinations with other cytokine functional SNPs determine the outcome of disease severity in tuberculosis. [ABSTRACT FROM AUTHOR]