Defect Engineering and Carbon Supporting to Achieve Ni‑Doped CoP_(3) with High Catalytic Activities for Overall Water Splitting

This work reports the use of defect engineering and carbon supporting to achieve metal-doped phosphides with high activities and stabilities for the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)in alkaline media.Specifically,the nitrogen-doped carbon nanofiber-supported Ni-doped CoP_(3) with rich P defects(Pv·)on the carbon cloth(p-NiCoP/NCFs@CC)is synthesized through a plasma-assisted phosphorization method.The p-NiCoP/NCFs@CC is an efficient and stable catalyst for the HER and the OER.It only needs overpotentials of 107 and 306 mV to drive 100 mA cm^(-2) for the HER and the OER,respectively.Its catalytic activities are higher than those of other catalysts reported recently.The high activities of the p-NiCoP/NCFs@CC mainly arise from its peculiar structural features.The density functional theory calculation indicates that the Pv·richness,the Ni doping,and the carbon supporting can optimize the adsorption of the H atoms at the catalyst surface and promote the strong electronic couplings between the carbon nanofiber-supported p-NiCoP with the surface oxide layer formed during the OER process.This gives the p-NiCoP/NCFs@CC with the high activities for the HER and the OER.When used in alkaline water electrolyzers,the p-NiCoP/NCFs@CC shows the superior activity and excellent stability for overall water splitting.

MicroRNA transcriptome analysis of chicken embryo fibroblast cells infected with Newcastle disease virus variants

Variations in the pathogenicity of Newcastle disease virus(NDV),the agent causing Newcastle disease,are associated with variants of different virulence.A few studies have characterized the expression of microRNAs(miRNAs)in NDV-infected avian cells.Here,the expression of miRNAs in chicken embryo fibroblasts(CEFs)infected with Herts/33 and LaSota NDV strains(highly virulent and nonvirulent,respectively)was determined using RNA sequencing.miRNAs involved in NDV infection included 562 previously documented and 184 novel miRNAs.miRNA target genes involved transcription factors,cell apoptosis,ubiquitin-mediated proteolysis,and protein processing in the endoplasmic reticulum.Potential target genes associated with autophagy were verified by qRT-PCR.No studies have documented the miRNA profles of CEFs infected with NDVs variants.This study adds to our knowledge of the cellular miRNAs involved in NDV infection and the complex molecular mechanisms mediating virus-host interactions.The results of this study will aid the development of strategies against the chicken virus.

Valproic acid therapy decreases serum 25-hydroxyvitamin D level in female infants and toddlers with epilepsy-a pilot longitudinal study

To evaluate if valproic acid(VPA)therapy is associated with vitamin D deficiency among infants and toddlers with epilepsy,a cross-sectional clinical study was conducted in 25 children with epilepsy taking VPA.Blood levels of calcium,phosphorus,alkaline phosphatase,and 25-hydroxy vitamin D[25(OH)D]and plasma VPA level were measured at 1-to 3-month intervals.At the initial and final measurements,vitamin D deficiency or insufficiency was recognized in 8(32%)and 12(42%),respectively.In girls,a decreasing trend in serum25(OH)D levels(P<0.05)was observed.Polytherapy had a significant negative effect on the longitudinal change of 25(OH)D(P<0.05)in girls.In conclusion,our study indicates that a high proportion of girls after VPA therapy had hypovitaminosis D.

Involvement of triadimefon induced early ABA-dependent H2O2 accumulation in soybean against water stress

The present study showed that pretreatment of triadimefon(TDM),a triazole compound,could improve tolerance of soybean seedlings to subsequent water stress.TDM pretreatment resulted in early and late rise in superoxide dismutase(SOD)and catalase(CAT)activities,and upregulation of ascorbate(As A)content in non-stressed and water-stressed seedlings,leading to late increase in net photosynthetic rate(Pn),late decrease in hydrogen peroxide(H2O2)and electrolyte leakage in stressed ones.These TDM-induced changes were blocked by application of abscisic acid(ABA)biosynthesis inhibitor tungstate,which inhibited early rise of ABA and H2O2contents in non-stressed and stressed seedlings.However,ABA pretreatment overcomed the effects of this inhibitor.Application of NADPH oxidase inhibitor diphenyleneiodonium(DPI),polyamine oxidase(PAO)inhibitor 2-hydroxyethylhydrazine(2-HEH)and H2O2scavenger dimethylthiourea(DMTU)prevented early TDM-induced rise of H2O2content.DPI,2-HEH and DMTU also decreased SOD,CAT and As A levels,but did not affect ABA content during early and late phases in both seedlings pretreated with TDM.In addition,these chemicals decreased Pn,and increased H2O2content and electrolyte leakage during late phase in TDM-pretreated stressed seedlings.Overall,these results indicated that TDM pretreatment alleviated adverse effects of water stress on soybean seedlings,which was at least in part,due to increase of antioxidant capacity and decrease of oxidative damage induced by early ABA-dependent H2O2generation.

Janus hydrogel with dual antibacterial and angiogenesis functions for enhanced diabetic wound healing

Anti-infection and neovascularization at the wound site are two vital factors that accelerate diabetic wound healing. However, for a wound healing dressing, the two functions need to work at different sites(inner and outer), giving big challenges for dressing design. In this study, we fabricated a novel sodium alginate/chitosan(SA/CS) Janus hydrogel dressing by the assembly of SA hydrogel loaded with silver nanoparticles(Ag NPs) and CS hydrogel impregnated with L-arginine loaded sodium alginate microspheres(Arg MSs) based on electrostatic interactions to combine the two functions. The outer SA-Ag NP hydrogel could prevent infection while avoiding the deposition of Ag NPs in the wound site, and the inner CS-Arg MS hydrogel on the wound surface could realize the sustained release of L-arginine and promote vascular regeneration. The composition, morphology and swelling/degradation of the SA-Ag NP/CS-Arg MS hydrogel were characterized systematically. L-Arginine release behavior has been tested and SA-Ag NP/CSArg MS hydrogel has been confirmed for excellent biocompatibility. Antibacterial and angiogenesis assays demonstrated the antibacterial and angiogenesis characteristics of the SA-Ag NP/CS-Arg MS hydrogel. Finally, in vivo diabetic wound healing assay demonstrated that the SA-Ag NP/CS-Arg MS hydrogel could significantly accelerate re-epithelialization, granulation tissue formation, collagen deposition and angiogenesis, thereby resulting in enhanced diabetic wound healing。

A polyphenol-modified chitosan hybrid hydrogel with enhanced antimicrobial and antioxidant activities for rapid healing of diabetic wounds

High oxidative stress injury and bacterial infection are the main challenges that impair wound healing in diabetic patients.Therefore,a hydrogel with enhanced antimicrobial and antioxidant properties was developed for rapid healing of diabetic wounds.In this study,chitosan methacrylate-gallic acid(CSMA-GA)polymer with antioxidant activity,antimicrobial activity,and ultraviolet(UV)-triggered gelling properties was developed as a hydrogel precursor.Meanwhile,amphiphilic Pluronic F127 molecules were used to load hydrophobic chlorhexidine drug molecules to obtain F127/chlorhexidine nanoparticle(NP)with strong antibacterial activity.Subsequently,F127/chlorhexidine NPs were encapsulated in CSMA-GA hydrogel to further enhance its antibacterial activity.The hybrid hydrogel platform(CSMA-GA/F127/chlorhexidine(CMGFC))exhibited high antibacterial efficiency(>99.9%)and strong reactive oxygen species(ROS)scavenging ability(>80.0%),which effectively protected cells from external oxidative stress(upregulated superoxide dismutase(SOD)and glutathione/oxidized glutathione disulfide(GSH/GSSG)levels and downregulated malondialdehyde(MDA)levels).Moreover,in vivo results proved that the CMGFC hydrogel significantly reduced inflammatory responses(downregulated interleukin-6(IL-6)and upregulated interleukin-10(IL-10)levels),promoted angiogenesis(upregulated vascular endothelial growth factor(VEGF)and platelet endothelial cell adhesion molecule-1(CD 31)levels),and wound healing(enhanced collagen deposition and tissue remodelling).Overall,the CMGFC hydrogel with enhanced antimicrobial and antioxidant properties demonstrated significant potential to enhance diabetic wound healing.

A novel hydrogel with glucose-responsive hyperglycemia regulation and antioxidant activity for enhanced diabetic wound repair

Enhanced diabetic wound repair remained a global challenge.Herein,we reported a novel hydrogel with glucose-responsive hyperglycemia regulation and antioxidant activity for enhanced diabetic wound repair.In this study,gallic acid(GA)with strong antioxidant activity was grafted onto chitosan(CS)chains by one-step synthesis,and then incorporated into poly(ethylene glycol)diacrylate(PEG-DA)hydrogel matrix to obtain a novel antioxidant hybrid hydrogel(PEG-DA/CS-GA).Meanwhile,polyethyleneimine(PEI)was modified with a unique glucose-sensitive phenylboronic acid(PBA)molecule to load insulin(PEIPBA/insulin nano-particles,PEI-PBA/insulin NPs),which could be immobilized in the PEG-DA/CS-GA hybrid hydrogel by the formation of dynamic borate bond between the phenylboronic acid groups on the PEI-PBA and the polyphenol groups on the CSGA.The results indicated that the PEG-DA/PEI-PBA/insulin/CS-GA(PPIC)hydrogel platform not only had remarkable biocompatibility,but also displayed extraordinary antioxidant properties(DPPH scavenging rate>95.0%),and effectively protected cells from oxidative damage(decreased MDA levels,increased Superoxide dismutase(SOD)levels and stable GSH/GSSG levels).Meanwhile,the PPIC hydrogel also exhibited unique glucose-responsive insulin release characteristics,and effectively regulated the blood glucose level.The in vitro and in vivo results demonstrated that our PPIC hydrogel could promoted angiogenesis(increased VEGF and CD 31 expression),reshaped the inflammatory microenvironment(decreased IL-6 and increased IL-10 level),and achieved wound closure within 20 days.All these results strongly indicated that the PPIC hydrogel represented a tough and efficient platform for diabetic wound treatment.

Application of metal-based biomaterials in wound repair

Wound repair,as one of the most intricate biological mechanisms,is essential to ensure the formation and integrity of the skin barrier.However,multiple factors can cause delays and severe debilitating effects in wound repair,which bring serious challenges.Metal elements such as calcium,copper,iron,and zinc serve irreplaceable roles in various regulatory pathways of the human body and directly or indirectly affect the orderly wound repair process.Biomaterials have proven to be an attractive strategy that can be applied to wound repair and have excellent potential to induce skin regeneration.In recent decades,with in-depth research on the regulatory mechanisms of metal elements involved in wound repair,metal-based biomaterials have been widely reported.Metal-based zero-dimensional(0D)biomaterials such as Angstrom-scale metallic materials and metal quantum dots,metal-based one-dimensional(1D)biomaterials such as nanorods,nanowires and nanofibers,metal-based two-dimensional(2D)biomaterials such as nanofilms and nanosheets,and metal-based three-dimensional(3D)biomaterials such as nanoframes have achieved remarkable results,which provide great support for accelerated wound repair.In this review,we systematically investigated the advances and impacts of various metal-based biomaterial platforms for wound repair to provide valuable guidance for future breakthroughs in wound treatment.

Synthesis of Qinghaosu Analogues from Dihydroqinghao Aldehyde： A Dark Singlet Oxygen Approach

A range of qinghaosu （artemisinin） analogues were synthesized from modified dihydroqinghao acid/aldehyde using dark singlet oxygen to trigger off the key step of the trioxane formation. The newly accessed 1,2,4-trioxanes featured a side chain extended from the carbon corresponding to the lactone carbonyl group of qinghaosu through a stable carbon-carbon single bond instead of an acetal oxygen-carbon bond in most similar analogues in the literature Biotin and various amines were also connected to the qinghaosu core, respectively, through such a linear tether in efforts to develop hybrids and potentially useful probes in search of the in vivo targets.

Several Enantiopure Chiral Building Blocks Derived from D-Mannose and a Formal Synthesis of Dubiusamine C

Several multi-functional chiral building blocks derived from D-mannose are developed, which may find diverse utilities as sources of 1-hydroxy-3-methyl structural units in enantioselective synthesis of many natural products. A formal synthesis of natural dubiusamine-C is also presented.

Synthesis and Absolute Configuration of Two Natural Phenolic Homobenzyl Esters

Two recently identified natural phenolic homobenzyl esters, isolated from Phragmipedium calurum （an orchid） and Eupatoriumfortunei TURCZ （a perennial herb in the Asteraceae family）, respectively, were synthesized in enantiopure forms. By comparison of the optical rotations for the synthetic and the natural samples, the absolute configurations for the natural products were reliably assigned. The synthesis also enables establishment of the absolute configuration of a closely related natural homobenzyl alcohol and provided for the first time complete physical and spectroscopic data for two other natural homobenzyl esters.