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Background: Oxidized lipid mediators such as eicosanoids play a central role in the inflammatory response associated with tuberculosis (TB) pathogenesis. Diabetes mellitus (DM) leads to marked changes in lipid mediators in persons with TB. However, the associations between diabetes-related changes in lipid mediators and clearance of M. tuberculosis (Mtb) among persons on anti-TB treatment (ATT) are unknown. Quantification of urinary eicosanoid metabolites can provide insights into the circulating lipid mediators involved in Mtb immune responses. Methods: We conducted a multi-site prospective observational study among adults with drug-sensitive pulmonary TB and controls without active TB; both groups had subgroups with or without dysglycemia at baseline. Participants were enrolled from RePORTBrazil (Salvador site) and RePORT-South Africa (Durban site) and stratified according to TB status and baseline glycated hemoglobin levels: a) TB-dysglycemia (n=69); b) TBnormoglycemia (n=64); c) non-TB/dysglycemia (n=31); d) non-TB/non-dysglycemia (n=29). We evaluated the following urinary eicosanoid metabolites: 11α-hydroxy-9,15- dioxo-2,3,4,5-tetranor-prostane-1,20-dioic acid (major urinary metabolite of prostaglandin E2, PGE-M), tetranor-PGE1 (metabolite of PGE2, TN-E), 9α-hydroxy11,15-dioxo-2,3,4,5-tetranor-prostane-1,20-dioic acid (metabolite of PGD2, PGD-M), 11-dehydro-thromboxane B2 (11dTxB2), 2,3-dinor-6-keto-PGF1α (prostaglandin I metabolite, PGI-M), and leukotriene E4 (LTE4). Comparisons between the study groups were performed at three time points: before ATT and 2 and 6 months after initiating therapy. Results: PGE-M and LTE4 values were consistently higher at all three time-points in the TB-dysglycemia group compared to the other groups (p<0.001). In addition, there was a significant decrease in PGI-M and LTE4 levels from baseline to month 6 in the TBdysglycemia and TB-normoglycemia groups. Finally, TB-dysglycemia was independently associated with increased concentrations of PGD-M, PGI-M, and LTE4 at baseline in a multivariable model adjusting for age, sex, BMI, and study site. These associations were not affected by HIV status. Conclusion: The urinary eicosanoid metabolite profile was associated with TBdysglycemia before and during ATT. These observations can help identify the mechanisms involved in the pathogenesis of TB-dysglycemia, and potential biomarkers of TB treatment outcomes, including among persons with dysglycemia. [ABSTRACT FROM AUTHOR]

HIV /Mycobacterium tuberculosis (Mtb) co-infected individuals have an increased risk of tuberculosis prior to loss of peripheral CD4 T cells, raising the possibility that HIV co-infection leads to CD4 T cell depletion in lung tissue before it is evident in blood. Here, we use rhesus macaques to study the early effects of simian immunodeficiency virus (SIV) co-infection on pulmonary granulomas. Two weeks after SIV inoculation of Mtb-infected macaques, Mtb-specific CD4 T cells are dramatically depleted from granulomas, before CD4 T cell loss in blood, airways, and lymph nodes, or increases in bacterial loads or radiographic evidence of disease. Spatially, CD4 T cells are preferentially depleted from the granuloma core and cuff relative to B cell-rich regions. Moreover, live imaging of granuloma explants show that intralesional CD4 T cell motility is reduced after SIV co-infection. Thus, granuloma CD4 T cells may be decimated before many co-infected individuals experience the first symptoms of acute HIV infection. [Display omitted] • SIV rapidly replicates in Mtb granulomas of co-infected macaques • Granuloma CD4 T cells are depleted before those in blood, BAL, LNs, or spleen • CCR5+Eomes− Mtb-specific Th1 and Th1∗ cells in granulomas are preferentially depleted • SIV co-infection reduces motility of CD4 T cells in granulomas HIV-mediated destruction of CD4 T cells enhances susceptibility to Mycobacterium tuberculosis. Using macaques, Foreman et al. show that CD4 T cells in granulomas are depleted very rapidly after SIV co-infection, indicating that loss of immunity at the site of bacterial replication occurs long before signs of peripheral T cell depletion. [ABSTRACT FROM AUTHOR]

There is a significant increase in overweight and obesity in adolescents worldwide. Here, we performed a cross-sectional study to examine the potential association between food consumption profiles and overweight in a large number of adolescents from Brazil. Sampling by clusters and conglomerates was carried out in students of public schools in Salvador, Brazil, between June and December 2009 and 1496 adolescents were evaluated. Data on socio-epidemiological data, anthropometric status and food consumption were captured. Multivariate analyses, such as hierarchical clustering and correlation networks, were used to perform a detailed description of food consumption profiles. There were differences in age and anthropometric status related to sex. Four clusters of food groups were identified based on the intake profile in the study population. No disparities in food intake were observed in individuals stratified by sex or anthropometric status. Furthermore, network analysis revealed that overweight or obesity were hallmarked by a selectivity in the ingestion of food groups that resulted in the appearance of inverse correlations of consumption, which was not present in eutrophic adolescents. Thus, overweight and obesity are associated with preferential choices of ingestion of specific food groups, which result in the appearance of inverse correlations of consumption. Such knowledge may serve as basis for future targeted nutritional interventions in adolescents. [ABSTRACT FROM AUTHOR]

Pathogenic bacteria, such as Streptococcus pneumoniae , Staphylococcus aureus , Haemophilus influenzae and Moraxella catarrhalis, are important vaccine targets. The 10-valent pneumococcal conjugate vaccine (PCV10) acts on 10 differents S. pneumoniae serovars. However, this vaccine could also act on other bacteria genera, leading to dysbiosis. Moreover, the vaccination has also been associated with imbalances in the ratio between commensal and potentially pathogenic bacteria. Despite the wealth of studies assessing the influence of the microbiome on vaccine effects, how vaccination can influence the microbiome remains poorly understood. Herein, we assessed the effects of PCV10 on infant nasopharyngeal microbiome composition. Nasopharyngeal aspirates were collected from children with acute respiratory infection (ARI) aged 6–23 months. Two groups were composed of 48 vaccinated and 36 unvaccinated subjects. 16S ribosomal RNA sequencing was performed to assess bacterial composition and results were analyzed with QIIME. Similar bacterial compositions were observed in the unvaccinated and vaccinated samples. Principal component analysis also indicated a similar bacterial composition between the groups. In addition, bacterial diversity was not different between the vaccinated and unvaccinated samples. Accordingly, our results suggest that PCV10 vaccination promotes a specific response against its targets, thereby preserving the nosocomial microbiome. Although not statistically significant, Streptococcus and Haemophilus genera were increased in the vaccinated group, while Moraxella was decreased. Increases in Streptococcus may be associated with vaccine-target taxa replacement by non-pathogenic species. In sum, we observed that PCV10 vaccination acts by promoting a target-specific action against pathogenic bacteria and also induces commensal bacteria colonization without substantially changing the nasopharyngeal microbiome. [ABSTRACT FROM AUTHOR]