Heavy metals (HMs) pollution in the aquatic environment: Role of probiotics and gut microbiota in HMs remediation.

The presence of heavy metals (HMs) in aquatic ecosystems is a universal concern due to their tendency to accumulate in aquatic organisms. HMs accumulation has been found to cause toxic effects in aquatic organisms. The common HMs-induced toxicities are growth inhibition, reduced survival, oxidative stress, tissue damage, respiratory problems, and gut microbial dysbiosis. The application of dietary probiotics has been evolving as a potential approach to bind and remove HMs from the gut, which is called "Gut remediation". The toxic effects of HMs in fish, mice, and humans with the potential of probiotics in removing HMs have been discussed previously. However, the toxic effects of HMs and protective strategies of probiotics on the organisms of each trophic level have not been comprehensively reviewed yet. Thus, this review summarizes the toxic effects caused by HMs in the organisms (at each trophic level) of the aquatic food chain, with a special reference to gut microbiota. The potential of bacterial probiotics in toxicity alleviation and their protective strategies to prevent toxicities caused by HMs in them are also explained. The dietary probiotics are capable of removing HMs (50-90%) primarily from the gut of the organisms. Specifically, probiotics have been reported to reduce the absorption of HMs in the intestinal tract via the enhancement of intestinal HM sequestration, detoxification of HMs, changing the expression of metal transporter proteins, and maintaining the gut barrier function. The probiotic is recommended as a novel strategy to minimize aquaculture HMs toxicity and safe human health.

Effect of dibutyl phthalate on microalgal growth kinetics, nutrients removal, and stress enzyme activities.

The dibutyl phthalate (DPB) is an emerging plasticizer contaminant that disrupts the biological processes of primary producers, especially phytoplankton. In this study, two microalgal species (Chlorella sp. GEEL-08 and Tetradesmus dimorphus GEEL-04) were exposed to various concentrations of DBP extending from 0 to 100 mg/L. The growth kinetics, N-nitrate, and P-phosphate removal efficiency were assessed. The response enzymes such as malonaldehyde (MDA) and superoxide dismutase (SOD) were also investigated. The results revealed that the Chlorella sp. GEEL-08 at 10 mg/L concentration of DBP exhibited higher growth (0.88 OD680nm) compared to T. dimorphus GEEL-04 (0.80 OD680nm). More than 94% of N and P were removed from culture media by both microalgal species. The DBP (>50 mg/L) significantly exacerbates the growth of both microalgae species and the growth inhibition ratio was in the range of 3.6%-25.9%. The SOD activity and MDA were higher in T. dimorphus culture media than in the culture media of Chlorella sp. The results reflect the hazard and the risk of plasticizers on primary producers in the ecosystem.

Case report of pseudoelevated serum testosterone in women and literature review / 中华检验医学杂志

Objective:The characteristics of women with false elevated testosterone were analyze and the literature was reviewed to provide reference for clinical laboratory identification of false elevated testosterone.Methods:The characteristics of three patients with false elevated testosterone in Peking Union Medical College Hospital were analyzed retrospectively, and the results of different detection platforms and methods for the determination of testosterone levels were compared. International and domestic literatures related to false elevation of testosterone and detection methods of testosterone were searched for a comprehensive analysis from PUBMED and CNKI.Results:The levels of testosterone in 3 female patients were elevated by immunoassay and normal by mass spectrometry. They were excluded from the diagnosis of hyperandrogenemia. A total of 38 literatures related to testosterone detection were retrieved, of which 9 case reports of pseudohyperandrogenemia, among which 12 cases of pseudohyperandrogenemia were reported in 2 domestic literatures in 2021. All cases were confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Previous studies have clearly indicated that the result of routine immunoassay in clinical laboratory for the determination of female testosterone have poor correlation with the results of LC-MS/MS, with varying degrees of deviation.Conclusions:Immunoassay tests for female testosterone is susceptible to interference and lead to elevated false results. It is suggested that clinical laboratories evaluate the detection methods used and establish a identification program, and confirm samples with suspected pseudoelevated testosterone elevation using other immune platforms or LC-MS/MS.