A comprehensive characterization biotransformation of chlorinated paraffin by human and carp liver microsomes via liquid chromatography-high-resolution mass spectrometry and screening algorithm.

The chlorinated paraffin (CP) monomer 1,2,5,6,9,10-Hexachlorodecane (CP-4) was subjected to in vitro biotransformation using human and carp liver microsomes. Five types of CP-4 metabolites (OH-, keto-, enol-, aldehyde- and carboxy-CP-4) were identified in human liver microsomer while only mono-OH-CP-4 was found in the carp liver microsomes. Kinetic studies revealed that the formation of mono-, di-, tri-hydroxylated CP-4, keto-, enol-, and aldehyde-CP-4 in human liver microsomes was best described by substrate inhibition models, whereas the formation of carboxylated CP-4 metabolites best fit the Michaelis-Menten model.

Accumulation of lipophilic and proteinophilic halogenated organic pollutants (HOPs) in the different types of feathers of laying hens.

This study investigated the bioaccumulation of halogenated organic pollutants (HOPs) in three types of feathers from laying hens through exposure experiments. The HOPs included lipophilic polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), as well as proteinophilic perfluoroalkyl carboxylic acids (PFCAs). Concentrations of PCBs, PBDEs, and short-chain PFCAs (≤8) were significantly higher in the body feathers than in the primary feathers, while long-chain PFCAs (>8) showed no significant differences among primary, tail, and body feathers.

Comprehensive evaluation of skin exposure to PBDEs and PCBs in diverse South China populations via dermal wipe sampling.

This study analyzed skin wipe samples from the forehead, palm, forearm, and lower leg of 120 volunteers across different age groups-preschoolers, thresholders, middle-aged, and elderly-with each group comprising 30 individuals with a balanced sex ratio from a city in South China. The research aimed to assess the occurrence, concentration, and associated health risks of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) adsorbed onto human skin from environmental sources. We identified 13 PBDE congeners and 10 PCB congeners across all samples, with average detection frequencies of 48% for PBDEs and 16% for PCBs, with concentrations ranging from non-detectable (ND) to 4200 and ND to 2300 ng/m, respectively.

The combined effect of diabetes mellitus and sarcopenia on depression and cognitive function: insights from the CHARLS cohort, 2011-2020.

Background: Diabetes mellitus (DM) and sarcopenia are bidirectionally linked and commonly co-occur among middle-aged and elderly individuals. This study aims to examine the combined effect of DM and sarcopenia on depressive symptoms and cognitive function.

Methods: This was a nationwide cohort study using data from the China Health and Retirement Longitudinal Study.

Nontarget analysis and characterization of p-phenylenediamine-quinones and -phenols in tire rubbers by LC-HRMS and chemical species-specific algorithm.

Background: N,N'-disubstituted p-phenylenediamine-quinones (PPDQs) are oxidization derivatives of p-phenylenediamines (PPDs) and have raised extensive concerns recently, due to their toxicities and prevalence in the environment, particularly in water environment. PPDQs are derived from tire rubbers, in which other PPD oxidization products besides reported PPDQs may also exist, e.g.

Rescue of morphological defects in by the alkaline volatile compound trimethylamine.

Unlabelled: Microorganisms can produce a vast diversity of volatile organic compounds of different chemical classes that are capable of mediating intra- and inter-kingdom interactions. In this study, we showed that the soil-dwelling bacterium can produce alkaline volatiles under multiple growth conditions, which we discovered through investigation of the mutant strain MU-1. Strain MU-1 has a defective morphology and exhibits a bald phenotype due to the lack of aerial mycelia and spores, as confirmed by scanning electron microscopy.

Species-specific metabolism of triphenyl phosphate and its mono-hydroxylated product by human and rat CYP2E1 and the carp ortholog.

Organophosphorus flame retardants (PFRs) are a class of flame retardants and environmental pollutants with various biological effects. Recentstudies have evidenced activation of some PFRs by human CYP enzymes (including CYP2E1) for genotoxic effects. However, the activity of CYPs in fish species toward PFR metabolism remains unclear.

Tissue-Specific Distribution and Maternal Transfer of Persistent Organic Halogenated Pollutants in Frogs.

Persistent organic pollutants pose a great threat to amphibian populations, but information on the bioaccumulation of contaminants in amphibians remains scarce. To examine the tissue distribution and maternal transfer of organic halogenated pollutants (OHPs) in frogs, seven types of tissues from black-spotted frog (muscle, liver, kidney, stomach, intestine, heart, and egg) were collected from an e-waste-polluted area in South China. Among the seven frog tissues, median total OHP concentrations of 2.

Prediction of embryo euploidy and pregnancy outcome by blastocyst morphology and development speed for women receiving single embryo transfer.

Background: Selection of high-quality blastocysts is the most important factor determining the success of assisted reproductive technology. The objective of this study is to assess the values of blastocyst morphological quality and development speed for predicting euploidy and clinical pregnancy outcome.

Methods: A total of 155 preimplantation genetic testing cycles including 959 blastocysts and 154 euploid blastocyst transfer cycles conducted between January 2018 and December 2019 were retrospectively analysed.

Tetrabromobisphenol-A/S and their derivatives in surface particulates from workshop floors of three representative e-waste recycling sites in China.

Surface particulates collected from the workshop floors of three major e-waste recycling sites (Taizhou, Qingyuan, and Guiyu) in China were analyzed for tetrabromobisphenol A/S (TBBPA/S) and their derivatives to investigate the environmental pollution caused by e-waste recycling activities. Mean concentrations of total TBBPA/S analogs in surface particulates were 31,471-116,059 ng/g dry weight (dw). TBBPA, TBBPA-BGE, and TBBPA-BDBPE were the most frequently detected in particulates with average concentration ranges of 17,929-78,406, 5601-15,842, and 5929-21,383 ng/g dw, respectively.

Comprehensive exploration of the anaerobic biotransformation of polychlorinated biphenyls in Dehalococcoides mccartyi CG1: Kinetics, enantioselectivity, and isotope fractionation.

Anaerobic microbial transformation is a key pathway in the natural attenuation of polychlorinated biphenyls (PCBs). Much less is known about the transformation behaviors induced by pure organohalide-respiring bacteria, especially kinetic isotope effects. Therefore, the kinetics, pathways, enantioselectivity, and carbon and chlorine isotope fractionation of PCBs transformation by Dehalococcoides mccartyi CG1 were comprehensively explored.

Comprehensive characterization and prioritization of halogenated organic compounds in fish and their implications for exposure.

Fish are an important pollution indicator for biomonitoring of halogenated organic compounds (HOCs) in aquatic environments, and HOCs in fish may pose health threats to consumers. This study performed nontarget and comprehensive analyses of HOCs in fish from an e-waste recycling zone by gas chromatography-high-resolution mass spectrometry, and further prioritized their human exposure risks. A total of 1652 formulas of HOCs were found in the fish, of which 1222, 117, and 313 were organochlorines, organobromines, and organochlorine-bromines, respectively.

Occurrence, composition, and spatial distribution of dechlorane plus in surface sediments of black-odorous urban rivers across China.

China, one of the two dechlorane plus (DP) producers, might have become a major area of DP pollution. The environmental contamination status of DP in sediments across the whole of China has not yet been studied. In the current study, the pollution levels, spatial distribution, and compositions of DP were investigated comprehensively in surface sediments from 173 black-odorous urban rivers across China for the first time.

Historical Occurrence and Composition of Novel Brominated Flame Retardants and Dechlorane Plus in Sediments from an Electronic Waste Recycling Site in South China.

Novel brominated flame retardants (NBFRs) and dechlorane plus (DP) have been widely used as alternatives to traditional BFRs. However, little is known about the temporal trends of NBFR and DP pollution in e-waste recycling sites. In the current study, three composite sediment cores were collected from an e-waste-polluted pond located in a typical e-waste recycling site in South China to investigate the historical occurrence and composition of NBFRs and DP.

A comprehensive assessment of external exposure to persistent halogenated organic pollutants for residents in an e-waste recycling site, South China.

Human skin wipes from 30 participants, air, dust, and food items were collected from a former electronic waste site in South China to provide a comprehensive understanding of residents' exposure to halogenated flame retardants (HFRs) and polychlorinated biphenyls (PCBs). The total concentration of halogenated organic pollutants (HOPs) in the dust, air, food and skin wipes ranged 240-25000 ng/g, 130-2500 pg/m, 0.08-590 ng/g wet weight, and 69-28000 ng/m, respectively.

Multi-pathway exposure assessment of organophosphate flame retardants in a southern Chinese population: Main route identification with compound-specificity.

In this study, we conducted comprehensive organophosphorus flame retardant (PFR) exposure assessments of both dietary and non-dietary pathways in a rural population in southern China. Skin wipes were collected from 30 volunteers. Indoor and outdoor air (gas and particles), dust in the houses of these volunteers, and foodstuffs consumed by these volunteers were simultaneously collected.

Arabidopsis PHYTOALEXIN DEFICIENT 4 promotes the maturation and nuclear accumulation of immune-related cysteine protease RD19.

Arabidopsis PHYTOALEXIN DEFICIENT 4 (PAD4) has an essential role in pathogen resistance as a heterodimer with ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1). Here we investigated an additional PAD4 role in which it associates with and promotes the maturation of the immune-related cysteine protease RESPONSIVE TO DEHYDRATION 19 (RD19). We found that RD19 and its paralog RD19c promoted EDS1- and PAD4-mediated effector-triggered immunity to an avirulent Pseudomonas syringae strain, DC3000, expressing the effector AvrRps4 and basal immunity against the fungal pathogen Golovinomyces cichoracearum.

Spatial distribution, conversion, and ecological risk assessment of hexabromocyclododecanes in the sediments of black-odorous urban rivers nationwide in China.

Hexabromocyclododecanes (HBCDs) have become a global pollution problem, particularly in China-a major producer and user of HBCDs. However, little is known about the HBCD pollution status in urban rivers nationwide in China. In this study, we comprehensively investigated the pollution characteristics of HBCDs in 173 sediment samples from black-odorous urban rivers across China.

Nontarget Analysis and Comprehensive Characterization of Iodinated Polyfluoroalkyl Acids in Wastewater and River Water by LC-HRMS with Cascade Precursor-Ion Exclusions and Algorithmic Approach.

Poly- and perfluoroalkyl acids (PFAAs) are a large family of widespread contaminants of worldwide concern and well-known as "forever chemicals". Direct emission of PFAAs from the fluorochemical industry is a crucial source of PFAA pollutants in the environment. This study implemented nontarget analysis and comprehensive characterization for a category of new PFAA contaminants, i.

Trophic Transfer of Halogenated Organic Pollutants in a Wetland Food Web: Insights from Compound-Specific Nitrogen Isotope of Amino Acids and Food Source Analysis.

A trophic position (TP) model (TP model) that simultaneously considered trophic discrimination factor and β variations was developed in this study and was first applied to investigate the trophic transfer of halogenated organic pollutants (HOPs) in wetland food webs. The TP model characterized the structure of the wetland food web more accurately and significantly improved the reliability of TMF compared to the TP, TP, and TP models, which were calculated based on the methods of stable nitrogen isotope analysis of bulk, traditional AAs-N-CSIA, and weighted β, respectively. Food source analysis revealed three interlocking food webs (kingfisher, crab, and frogs) in this wetland.

In situ observation of cartilage matrix based on two-photon fluorescence microscopy.

Articular cartilage lesions remain a major challenge for clinicians and researchers. Several techniques, such as histological scoring, magnetic resonance imaging, and tissue section staining, are available for detecting cartilage degeneration and lesions and evaluating cartilage repairs. Nevertheless, these methods are complex and have numerous influencing factors, which may present obstacles to efficient communication between studies.

Bioaccumulation, tissue distributions, and maternal transfer of perfluoroalkyl carboxylates (PFCAs) in laying hens.

Laying hens were exposed to feeds spiked with a series of perfluoroalkyl carboxylates (PFCAs) ranging from perfluorobutanoic acid (C4) to perfluorooctadecanoic acid (C18) to investigate their bioaccumulation, tissue distribution, and maternal transfer. We found that PFCAs with longer carbon chains (>8) were more efficiently absorbed in the gastrointestinal tract than those with shorter chains (≤8), and that the rate of depuration varied inversely with the carbon chain length in a U-shaped pattern. Moreover, bioaccumulation potential increased with increasing carbon-chain length, except for C4.

Anaerobic biotransformation of two novel brominated flame retardants: Kinetics, isotope fractionation and reaction mechanisms.

1,2,5,6-tetrabromocyclooctane (TBCO) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), as safer alternatives to traditional brominated flame retardants, have been extensively detected in various environmental media and pose emerging risks. However, much less is known about their fate in the environment. Anaerobic microbial transformation is a key pathway for the natural attenuation of contaminants.