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The presence and distribution of antibiotics and antibiotic resistance genes (ARGs) in rivers have attracted significant global concern. However, research on the contamination of typical rivers in Sichuan Province, China, remains limited. This study aimed to assess the residual levels of antibiotics across 42 national and provincial monitoring sites in nine rivers within Sichuan using UPLC-MS/MS. Ecological risk levels were evaluated through established risk assessment methods, and antibiotic resistance in Escherichia coli(E.coli) isolated from these waters was determined using the Kirby-Bauer disk diffusion method. Additionally, redundancy analysis (RDA) was conducted to explore the impact of residual antibiotics on the microbial community structure in the Minjiang River basin. Antibiotics were detected in all nine rivers studied, with the Minjiang, Tuojiang, and Jialingjiang rivers exhibiting particularly severe contamination, with concentrations ranging from 0.29 to 2233.71 ng/L. The level of antibiotic pollution in the Sichuan Basin was significantly higher than in other regions of Sichuan, likely due to the area's high population density. Furthermore, 9.77% of E. coli isolates from the nine rivers exhibited antibiotic resistance, with over 5.8% demonstrating multidrugs resistance. Norfloxacin, amoxicillin, ampicillin, and tetracycline were identified as the primary contributors to the high ecological risk at 26 of the 42 monitoring sites. A strong correlation was observed between residual antibiotics and changes in microbial community structure. These findings provide critical insights into the distribution of antibiotics and ARGs in the rivers of Sichuan Province and highlight the urgent need for targeted strategies to mitigate antibiotic pollution. Addressing this issue is essential to protect both ecological integrity and public health. [ABSTRACT FROM AUTHOR]

Obesity and overweight are common modern health challenges. Caloric intake greater than that needed for energy production results in excess storage of fat in the abdomen. Visceral fat secretes a wide spectrum of adipokines, and increased adiposity is associated with a higher risk of development of metabolic disorders. In addition, adipose tissue secretes extracellular vesicles (EVs) to communicate with peripheral cells and distant organs, and regulate whole-body metabolism. Furthermore, clinical evidence has shown that adipose tissue-derived EVs are present at low levels in the circulation of healthy individuals. In contrast, individuals with metabolic syndrome have significantly higher levels of circulating adipose-derived EVs. The composition of the contents of EVs is dynamic, and closely mirrors individual daily habits and fasting-fed state metabolic characteristics. In this mini-review, we aimed to elucidate the role of adipocyte-derived EVs in regulation of whole-body metabolism under physiological and pathophysiological conditions. Studies have shown that adipose tissue may be a major source of circulating exosomal miRNAs that regulate metabolic homeostasis and directly promote insulin-resistance in other organs. Furthermore, the composition of adipocyte-derived circulating miRNAs in EVs may change prior to development of metabolic disorder. Adipocyte-derived miRNAs in EVs may also induce obesity-related changes such as M1 polarization and inhibition of M2 polarization of macrophages, which may affect the biological behaviors of surrounding tumor cells., (Copyright © 2020 Zhou and Tan.)