RESUMEN
Human exposure to heavy metals, which encompasses both essential and toxic varieties, is widespread. The intestine functions as a critical organ for absorption and metabolism of heavy metals. Gut microbiota plays a crucial role in heavy metal absorption, metabolism, and related processes. Toxic heavy metals (THMs), such as arsenic (As), mercury (Hg), lead (Pb), and cadmium (Cd), can cause damage to multiple organs even at low levels of exposure, and it is crucial to emphasize their potential high toxicity. Nevertheless, certain essential trace elements, including iron (Fe), copper (Cu), and manganese (Mn), play vital roles in the biochemical and physiological functions of organisms at low concentrations but can exert toxic effects on the gut microbiota at higher levels. Some potentially essential micronutrients, such as chromium (Cr), silicon (Si), and nickel (Ni), which were considered to be intermediate in terms of their essentiality and toxicity, had different effects on the gut microbiota and their metabolites. Bidirectional relationships between heavy metals and gut microbiota have been found. Heavy metal exposure disrupts gut microbiota and influences its metabolism and physiological functions, potentially contributing to metabolic and other disorders. Furthermore, gut microbiota influences the absorption and metabolism of heavy metals by serving as a physical barrier against heavy metal absorption and modulating the pH, oxidative balance, and concentrations of detoxification enzymes or proteins involved in heavy metal metabolism. The interactions between heavy metals and gut microbiota might be positive or negative according to different valence states, concentrations, and forms of the same heavy metal. This paper reviews the metabolic interactions of 10 common heavy metals with the gut microbiota and their health implications. This collated information could provide novel insights into the disruption of the intestinal microbiota caused by heavy metals as a potential contributing factor to human diseases.
RESUMEN
Objective@#To investigate the development of public health human resource of the Centers for Disease Control and Prevention (CDCs) in Zhejiang Province from 2016 to 2020, so as to put forward the strategies for the talent team construction of CDCs.@*Methods@#The general information of personnel of CDCs in Zhejiang Province from 2016 to 2020 was collected through China Information System for Disease Control and Prevention. A questionnaire survey and a qualitative interview were conducted to collect the data of staffing, talent training, salary and employee turnover, and to analyze the development of the talent team of CDCs. @*Results@#By 2020, there were 105 CDCs, including 1 provincial, 11 prefectural and 93 county-level CDCs, and 5 277 staff on-the-job. From 2016 to 2020, the number of staff per 10 000 permanent residents in the province, prefecture and county levels were 0.062-0.070, 0.170-0.188 and 0.585-0.604, respectively, which did not meet the standard for the personnel establishment in Zhejiang CDCs; the proportion of the staff with bachelor degree or above increased from 90.05% to 94.25%; the proportion of the health professionals decreased from 82.91% to 80.01%; the proportion of the staff with senior professional titles increased from 35.20% to 45.25%. The results of the qualitative interview indicated a lack of health professionals and high-end talents, a gap between the approved staffing and post requirements, as well as demands for a stable team and higher pay. @*Conclusion@#From 2016 to 2020, the structure of educational background, major and professional title among the on-the-job staff of CDCs in Zhejiang Province has been improving; however, the total allocation of human resource is insufficient, and the stability and treatment of staff need to be further improved.