Investigation into the roles of interfacial H_(2)O structure in catalytic oxidation of HCHO and CO over CuMnO_(2) catalysts

The rapid deactivation of cost-effective MnO_(2)-based catalysts in humid air limits their application in practice,and the identification of the role of water in an oxidation process is significant for developing water-resistant MnO_(2)-based catalysts.Here,CuMnO_(2)showed a20.3%HCHO conversion in 10 hr at room temperature in humid air with relative humidity of 40%,but deactivated in 3 hr in dry air.The excellent activity and stability of HCHO oxidation in humid air were attributed to the positive effect of H_(2)O on HCHO oxidation to the H_(2)O-HOCH_(2)OH supermolecule assemblies via hydrogen bonds formed on CuMnO_(2).H_(2)O-HOCH_(2)OH supermolecule assemblies tend to be oxidized to carbonate,which is further oxidized to CO_(2).Furthermore,CuMnO_(2)exhibited a much poorer activity of CO oxidation in humid air,but the CO conversion was still 100%in 10 hr in dry air.H_(2)O showed a competitive adsorption effect to CO on CuMnO_(2).CuMnO_(2)could be applied in HCHO elimination in humid air and CO elimination in dry air.

A sustained-release microcarrier effectively prolongs and enhances the antibacterial activity of lysozyme

Bacterial infections have become a great threat to public health in recent years.A primary lysozyme is a natural antimicrobial protein;however,its widespread application is limited by its instability.Here,we present a poly(N-isopropylacrylamide)hydrogel inverse opal particle(PHIOP)as a microcarrier of lysozyme to prolong and enhance the efficiency against bacteria.This PHIOP-based lysozyme(PHIOP-Lys)formulation is temperature-responsive and exhibits long-term sustained release of lysozyme for up to 16 days.It shows a potent antibacterial effect toward both Escherichia coli and Staphylococcus aureus,which is even higher than that of free lysozyme in solution at the same concentration.PHIOPs-Lys were demonstrated to effectively inhibit bacterial infections and enhance wound healing in a full-thickness skin wound rat model.This study provides a novel pathway for prolonging the enzymatic activity and antibacterial effects of lysozyme.

Potential Health Impact of Microplastics:A Review of Environmental Distribution,Human Exposure,and Toxic Effects

Microplastics are ubiquitous in the global environment.As a typical emerging pollutant,its potential health hazards have been widely concerning.In this brief paper,we introduce the source,identification,toxicity,and health hazard of microplastics in the human.The literature review shows that microplastics are frequently detected in environmental and human samples.Humans are potentially exposed to microplastics through oral intake,inhalation,and skin contact.We summarize the toxic effects of microplastics in experimental models like cells,organoids,and animals.These effects consist of oxidative stress,DNA damage,organ dysfunction,metabolic disorder,immune response,neurotoxicity,as well as reproductive and developmental toxicity.In addition,the epidemiological evidence suggests that a variety of chronic diseases may be related to microplastics exposure.Finally,we put forward the gaps in toxicity research of microplastics and their future development directions.This review will be helpful to the understanding of the exposure risk and potential health hazards of microplastics.

Effects of environmental contaminants on fertility and reproductive health

Recent research indicates that the human infertility rate is increasing. Although various reasons have been hypothesized for the growing infertility rate, environmental contaminants are potentially important causal agents associated with this change.Chemical contaminants are widespread throughout our environment and human exposure is virtually unavoidable. The overall contribution of environmental exposure to infertility is unknown, but studies involving occupational exposure, together with results from animal experiments, suggest that environmental contaminants may adversely affect fertility. We reviewed the adverse effects of environmental exposure on fertility and related reproductive outcomes. Environmental contaminants covered in this review include heavy metals, organic solvents, pesticides and endocrine disrupting chemicals. It is hoped that this review will highlight the need for further research in this area.

Tetrachloro-1,4-benzoquinone induces apoptosis of mouse embryonic stem cells

Pentachlorophenol（PCP） is a widespread,persistent environmental contaminant,and it is enzymatically activated to form a reactive metabolite,tetrachloro-l,4-benzoquinone（TCBQ）.To our knowledge,there is no information about TCBQ toxicity on embryonic stem cells.Here,we demonstrated that TCBQ induced significantly apoptosis of mouse embryonic stem cells in a concentration-dependent manner.We also showed that TCBQ elevated genomic5-hydroxymethylcytosine（5hmC） by affecting ten-eleven translocation（Tet） dioxygenases in mouse embryonic stem cells.We further investigated whether Tet dioxygenases were implicated in TCBQ-induced apoptosis.By depleting all three dioxygenases（Tet1-3）,we found that Tet dioxygenases slightly inhibited both early and late apoptosis induced by TCBQ at a low concentration（30 μmol/L）.Meanwhile,treated by TCBQ at higher concentrations（40and 50 μmol/L）,the total percentage of apoptotic cells was not affected by Tet dioxygenases.However,Tet dioxygenases tended to arrest mouse ES cells to be at early apoptotic stage and to reduce the cells to enter later apoptotic stage.These results indicate that Tet dioxygenases play a role in shaping TCBQ-induced apoptosis in mouse embryonic stem cells.Our study provides new insights into the toxicology of PCP and its reactive metabolite TCBQ.