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Introduction: Evidence has shown that air pollutant exposure plays a vital role in the progression of tuberculosis (TB). The aim of this research was to assess the short-term effects of ozone (O3) exposure and TB outpatient visits in 16 prefecture-level cities of Anhui, China, 2015– 2020.Methods: Distributed lag nonlinear model (DLNM), Poisson generalized linear regression model and random effects model were applied in this study. The effects of different age and gender on TB were investigated by stratified analysis, and then we performed sensitivity analyses to verify the stability of the results.Results: A total of 186,623 active TB cases were registered from January 1, 2015 to December 31,2020 in Anhui. The average concentration of ozone is 92.77 ± 42.95 μg/m3. The maximum lag-specific and cumulative relative risk (RR) of TB outpatient visits was 1.0240 (95% CI: 1.0170– 1.0310, lag 28 days) for each 10 μg/m³ increase in O3 in the single-pollutant model. Estimation for 16 prefecture-level cities indicated that the strong association between O3 and the risk of TB outpatient visits was in tongling (RR = 1.0555, 95% CI: 1.0089– 1.1042), Suzhou (RR = 1.0475, 95% CI: 1.0268– 1.0687), wuhu (RR = 1.0358, 95% CI: 1.0023– 1.0704). Stratified analysis showed that the health effects of ozone exposure remained significant in male and older adults, and there was no significant association between exposure to ozone in children and adolescents and the risk of tuberculosis.Discussion: We found that ozone exposure increases the risk of TB infection in outpatient patients, with males and the elderly being more susceptible, and it is necessary for government departments to develop targeted publicity and prevention measures in response to the local air quality conditions. [ABSTRACT FROM AUTHOR]

Objectives: The main target of current drugs for alleviating bone loss is osteoclasts. However, the long‐term application of such drugs will also cause side effects. Therefore, it is of great need to develop new and safer therapeutics for osteoporosis. In recent years, drug development based on gut microbiota has gradually attracted attention. This manuscript investigates the inhibitory effect of urolithin B (UB) on osteoclastogenesis and differentiation in vitro and in ovariectomized (OVX) mice. Materials and Methods: CCK‐8 was used to analyse the cytotoxicity of UB; BMMs cells were differentiated into osteoclasts by RANKL, and respectively treated with 1, 5, and 25 μmol/L UB during this process. After one week of intervention, tartrate‐resistant acid phosphatase (TRAP) staining was used to analyse the number and average area of osteoclasts. F‐actin staining and immunofluorescence staining were conducted to evaluate the morphology and function of osteoclasts. Bone resorption function of osteoclasts was detected by Pit Formation Assay. The expression of osteoclast‐related protein genes in RAW264.7 cells were investigated via western blot and RT‐PCR assays. Western blot analysis of RANKL‐mediated activation of MAPK/NF‐κB pathway after 0, 5, 15, 30, 60 min of intervention. For in vivo experiments, OVX mice received intraperitoneal injection of 10, 50 mg/kg every two days, 8 weeks later, the femurs of mice were taken for morphological analysis, and the serum content of CTX‐1, a bone metabolism index, was analysed. Results: UB could inhibit the osteoclast differentiation of rankl‐induced bone marrow macrophages (BMMs) and RAW264.7 cells in vitro, suppress the uptake activity of hydroxyapatite and expression of osteoclast‐related gene MMP9, CTSK, NFATc1 and c‐fos. Furthermore, UB repressed the rankl‐induced phosphorylation and degradation of IκB and the phosphorylation of P65 in the NF‐κB pathway of RAW264.7 cells, and also down‐regulated the phosphorylation level of ERK in the MAPK pathway. For in vivo studies, UB‐treated OVX mice showed more significant improved various parameters of distal femur compared with the control group, with fewer NFATc1, MMP9 and TRAP‐positive osteoclasts in bone tissues, and less serum content of CTX‐1. Conclusion: Urolithin B attenuated bone loss in OVX mice by inhibiting the formation and activation of osteoclasts via down‐regulation of the ERK/NF‐κB signalling pathway. [ABSTRACT FROM AUTHOR]

Carbon flux metasomatism in the subduction environment is an important process, but it remains poorly understood. The paucity of exposed lower crust and upper mantle rocks in continental arcs renders xenoliths a major target for studying the slab-derived carbon cycle. This study of the carbonate phases in volcanic rocks from three drill cores in Ulleung Island, South Korea, sheds light on the interaction of carbon flux in the upper mantle and lower crust in a back-arc setting. The volcanic rocks from Ulleung Island range in composition from trachybasalt to trachyte and contain abundant euhedral pseudomorphic carbonate grains, ulvöspinel-hosted and biotite-hosted carbonate-silicate melt inclusions, and irregular carbonate globules. Integrated petrographic and geochemical studies of a variety of phenocrysts, carbonate phases, and carbonate-silicate inclusions in biotite and ulvöspinel indicate that recharging of carbon flux affected magma evolution. Carbon and oxygen isotopes of the pseudomorphic carbonate grains overlap with mantle values, indicating a carbonatite-like origin of the carbonate phases. The (MgO,FeO,CaO)-rich silicates in ulvöspinel-hosted silicate inclusions and pseudomorphic carbonate grains likely represent a primary melt, which formed from the partial melting of carbonated eclogite of the subducted slab within the mantle wedge beneath Ulleung Island. A petrogenetic model is proposed to illustrate that the crystal mush in the magma chamber was intruded by carbonate-rich liquids and caused alteration of cumulate crystals to generate the euhedral pseudomorphic carbonate grains. The extrusive magma captured those pseudomorphic grains and erupted to form the trachybasalt-trachyte units. The observed carbonate phases and their geochemical characteristics indicate that carbon flux metasomatism played a fundamental role in this back-arc magmatism. [ABSTRACT FROM AUTHOR]