Objective This study aimed to comprehensively investigate the potential protective effects and underlying mechanisms of taurine against dihydrotestosterone(DHT)-induced androgenetic alopecia(AGA)in male C57BL/6 mice,w...Objective This study aimed to comprehensively investigate the potential protective effects and underlying mechanisms of taurine against dihydrotestosterone(DHT)-induced androgenetic alopecia(AGA)in male C57BL/6 mice,with a focus on hair follicle cycle modulation,cellular proliferation/apoptosis,and key related signaling pathways.Methods Six-week-old female C57BL/6 mice were initially used to assess the hair growth-promoting potential of taurine.After acclimatization,they were randomly assigned to three groups(n=8):control(regular drinking water),taurine(drinking water containing 1%taurine),and minoxidil(topical 2%minoxidil,positive control).For the AGA study,male C57BL/6 mice were randomly divided into five groups(n=8):control(physiological saline),DHT(model group,1 mg/d DHT),DHT+low-dose taurine(1 mg/d DHT+2 mg/d taurine),DHT+high-dose taurine(1 mg/d DHT+10 mg/d taurine),and DHT+minoxidil(positive control,1 mg/d DHT+topical 2%minoxidil).One day before treatment initiation,dorsal hair was shaved with scissors,and residual hair was removed using a depilatory cream.DHT and taurine were administered via daily intraperitoneal injection.Hair regrowth was assessed by photographing the depilated area at regular intervals and quantified using a four-point grading system(0-3).Dorsal skin samples were collected on day 14 for histological analysis(H&E staining),immunofluorescence staining(Ki67 for proliferation,TUNEL for apoptosis),ELISA(DHT quantification),RT-qPCR,and Western blot analysis to evaluate the expression of key genes and proteins(androgen receptor(AR),transforming growth factor(TGF)‑β1,TGF‑β2,Dickkopf-1(DKK1)).Results In female mice,taurine supplementation significantly accelerated hair growth,with effects comparable to minoxidil.This was evidenced by an earlier transition from pink(telogen)to black(anagen)skin and increased hair growth scores.Histological analysis showed that taurine increased hair follicle count and dermal thickness.Immunofluorescence confirmed enhanced keratinocyte proliferation in the hair matrix.In the DHTinduced AGA model,DHT significantly extended the telogen phase,inhibited hair growth,increased skin DHT content,and induced hair follicle miniaturization.Taurine treatment,particularly at the high dose,effectively counteracted these effects:it promoted the telogen-to-anagen transition and improved hair growth scores.Histomorphometric analysis showed that taurine significantly restored DHT-induced reductions in dermal thickness,hair follicle count,hair bulb depth,and follicle size.Taurine treatment also reduced apoptosis and promoted the proliferation of hair follicle cells,as demonstrated by Ki67 and TUNEL assays.Crucially,RT-qPCR and Western blot analyses revealed that DHT significantly up-regulated the expression of AR,TGF‑β1,TGF‑β2,and DKK1 at both mRNA and protein levels in dorsal skin.Taurine administration markedly down-regulated the expression of these pathogenic factors,bringing them closer to the levels observed in the control group.Conclusion Taurine demonstrates significant efficacy in alleviating DHT-induced AGA in male C57BL/6 mice.Its protective effects are mediated through multi-faceted mechanisms.(1)Promoting hair follicle cycle progression:it accelerates the transition from telogen to anagen,counteracting DHT-induced prolongation of the telogen phase.(2)Modulating cellular dynamics:it stimulates the proliferation of hair matrix keratinocytes and reduces DHT-induced apoptosis within hair follicle cells.(3)Suppressing androgen-driven pathogenic pathways:it downregulates the expression of critical molecules in the AGA pathway,including AR,the cytokines TGF-β1 and TGF-β2,and the Wnt pathway inhibitor DKK1.Given its favorable safety profile and multi-targeted action,taurine emerges as a promising novel therapeutic candidate or adjunct for treating AGA.Further investigation into its clinical potential and precise molecular mechanisms is warranted.This study provides a robust preclinical foundation for considering taurine supplementation or topical application in hair loss management strategies.展开更多
Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal sur...Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function.Increasing amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers.These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases.Through a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.展开更多
Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is...Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is imperative to adhere to standardized experiments and controls.This paper objectively reviews the origin,differentiation,and phenotypic and genetic differences between the C57BL/6 and BALB/c mouse substrains.Furthermore,an optimal selection strategy is proposed based on the genetic quality control technology to facilitate the precise application of these two mouse substrains.展开更多
Understanding the genetic diversity–area relationship(GAR)is essential for comprehending how species adapt to environmental changes,as genetic diversity is an indicator of a species’adaptive potential.Variation in e...Understanding the genetic diversity–area relationship(GAR)is essential for comprehending how species adapt to environmental changes,as genetic diversity is an indicator of a species’adaptive potential.Variation in environmental adaptation capacity exists among species and animal taxa with different distribution areas,highlighting the importance of understanding the GAR.To obtain a more comprehensive understanding of the GAR in terrestrial vertebrates,we assessed both haplotype diversity–area and nucleotide diversity–area relationships using 25,453 cytochrome c oxidase subunit I(COI)sequences from 142 amphibian species,574 bird species,and 342 mammal species.We found that both measures of genetic diversity increased with species range size across major animal groups.Nevertheless,the GAR did not differ among animal groups,while haplotype diversity performed better than nucleotide diversity in profiling the GAR,as indicated by higher R2 values.The difference in the modeling fit may stem from the distinct biological and mathematical significance of nucleotide diversity and haplotype diversity.These results suggest that the GAR follows similar rules among different animal taxa.Furthermore,haplotype diversity may serve as a more reliable indicator for assessing the potential effects of area size changes on animal populations and provide better guidance for conserving genetic diversity.展开更多
The efficient limitation of the"shuttle effect"of polysulfide from the rational construction of electrocatalysts to accelerate the redox kinetics of polysulfides is extremely important.In this work,the cobal...The efficient limitation of the"shuttle effect"of polysulfide from the rational construction of electrocatalysts to accelerate the redox kinetics of polysulfides is extremely important.In this work,the cobalt/Nickel bimetallic alloy polyhedrons decorated on layered TiO_(2)heterostructure(Co Ni@TiO_(2)/C)derived from MXene and bimetallic metal-organic framework have been prepared through liquid-phase deposition and high-temperature annealing processes.This heterostructure presents excellent electrical conductivity,which facilitates ion diffusion and electron transfer within the battery.Besides,the heterostructure from anchoring the Co Ni bimetallic alloy on the layered TiO_(2)ensures the full exposure of active sites and accelerates polysulfide redox kinetics through chemisorption and catalytic conversion.Considering these advantages mentioned above,when applied as the lithium-sulfur batteries(LSBs)separator modifier,the cell assembled from the Co Ni@TiO_(2)/C modified separator demonstrates high specific capacity(1481.7 mAh/g at 0.5 C),superior rate capability(855.5 mAh/g at 3 C)and excellent cycling performance,which can maintain the high capacity of 856.09 mAh/g after 300 cycles with low capacity decay rate of 0.09%per cycle.Even under a high sulfur loading of 4.4 mg/cm^(2),the cell can still present excellent cycling stability.This study paves the way for the design of novel material for the construction of an outstanding functional separator layer and shines the light on the effective and feasible way for the inhibition of shuttle effect in lithium-sulfur batteries.展开更多
Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most stud...Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most studies utilize gene knockout mice to explain the mechanisms.However,the production of genetically engineered mice is costly and time-consuming.In this study,we presented a convenient research strategy using an RNA interference(RNAi)and testicular transplantation approach.Histone H3 lysine 9(H3K9)methylation was dynamically regulated during spermatogenesis.As Jumonji domain-containing protein 1A(JMJD1A)and Jumonji domain-containing protein 2C(JMJD2C)demethylases catalyze histone H3 lysine 9 dimethylation(H3K9me2),we firstly analyzed the expression profile of the two demethylases and then investigated their function.Using the convenient research strategy,we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases.These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.展开更多
(±)-Penicithrones A–D(1a/1b–4a/4b),four novel pairs of anthrone–cyclopentenone heterodimers characterized by a distinctive bridged 6/6/6−5 tetracyclic core skeleton,together with three previously identified co...(±)-Penicithrones A–D(1a/1b–4a/4b),four novel pairs of anthrone–cyclopentenone heterodimers characterized by a distinctive bridged 6/6/6−5 tetracyclic core skeleton,together with three previously identified compounds(5–7),were isolated from the crude extract of the mangrove-derived fungus Penicillium sp.,guided by heteronuclear single quantum correlation(HSQC)-based small molecule accurate recognition technology(SMART 2.0)and liquid chromatography-tandem mass spectrometry(LC-MS/MS)-based molecular networking.The structural elucidation of new compounds was accomplished through comprehensive spectroscopic analysis,and their absolute configurations were determined using DP4+^(13)C nuclear magnetic resonance(NMR)calculations and electronic circular dichroism(ECD)calculations.Compounds 1a/1b–4a/4b demonstrated moderate cytotoxicity against three human cancer cell lines HeLa,HCT116 and MCF-7 with half maximal inhibitory concentration(IC50)values ranging from 15.95±1.64 to 28.56±2.59μmol·L–1.展开更多
BACKGROUND Liver imaging and transient elastography(TE)are both tools used to assess liver fibrosis and steatosis among people with hepatitis C virus(HCV)infection.However,the diagnostic accuracy of conventional imagi...BACKGROUND Liver imaging and transient elastography(TE)are both tools used to assess liver fibrosis and steatosis among people with hepatitis C virus(HCV)infection.However,the diagnostic accuracy of conventional imaging in detecting fibrosis and steatosis in this patient population remains unclear.AIM To investigate the correlation between steatosis and fibrosis and abnormal findings on liver imaging in patients with HCV.METHODS We conducted a retrospective cross-sectional analysis of patients with HCV at Grady Liver Clinic who had TE exams between 2018-2019.We analyzed the correlation of controlled attenuation parameter and liver stiffness measurement on TE and abnormal findings on liver imaging.Liver imaging findings(hepatic steatosis,increased echogenicity,cirrhosis,and chronic liver disease)were further evaluated for their diagnostic performance in detecting fibrosis(≥F2,≥F3,≥F4)and steatosis(≥S1,≥S2,≥S3).RESULTS Of 959 HCV patients who underwent TE,651 had liver imaging.Higher controlled attenuation parameter scores were observed in patients with abnormal liver findings(P=0.0050),hepatic steatosis(P<0.0001),and increased echogenicity(P<0.0001).Higher liver stiffness measurement values were also noted in those with abnormal liver(P<0.0001)and increased echogenicity(P=0.0026).Steatosis severity correlated with hepatic steatosis(r=0.195,P<0.001)and increased echogenicity(r=0.209,P<0.001).For fibrosis detection,abnormal liver imaging had moderate sensitivity(81.7%)and specificity(70.4%)for cirrhosis(≥F4),while cirrhosis on imaging had high specificity(99.2%)but low sensitivity(18.3%).Increased echogenicity showed high specificity(92.8%)but low sensitivity(20.9%)for steatosis detection.CONCLUSION Liver imaging detects advanced fibrosis and steatosis but lacks early-stage sensitivity.Integrating TE with imaging may improve evaluation in patients with HCV.展开更多
This study investigated the effects of interstitial carbon doping on the microstructural and magnetocaloric properties of off-stoichiometric La_(1.2)Fe_(11.6)Si_(1.4)Cx(x=0,0.25,0.5,0.75,1)alloys.The alloys were prepa...This study investigated the effects of interstitial carbon doping on the microstructural and magnetocaloric properties of off-stoichiometric La_(1.2)Fe_(11.6)Si_(1.4)Cx(x=0,0.25,0.5,0.75,1)alloys.The alloys were prepared by melt-spinning following vacuum arc-melting.For the as-prepared and annealed samples,the carbon existed in the La_(2)Fe_(2)Si_(2)C and NaZn_(13)-type La(Fe,Si)_(13)(denoted by 1:13)phases,respectively.During the annealing process,the C atoms inhibited the diffusion reaction and depressed the generation of 1:13 phase,reducing mass fraction of the 1:13 phase in annealed La_(1.2)Fe_(11.6)Si_(1.4)Cx compounds.The introduction of carbon resulted in lattice expansion and increased the Curie temperature(T_(C))from 192 K to 273 K with x=0.5.The first-order magnetic transition was gradually transformed into the second-order magnetic transition with increasing carbon content,which induced the significant reduction of thermal and magnetic hysteresis,as well as the maximum magnetic entropy change and adiabatic temperature change vary from 18.92 J/(kg·K)to 4.60 J/(kg·K)and from 4.9 K to 2.2 K under an applied field change of 0-2 T.The results demonstrate that interstitial carbon doping is an effective strategy to improve the magnetocaloric performance of La(Fe,Si)_(13)alloys.展开更多
Two landmark studies demonstrate synergistic approaches to gastrointestinal cancer management.Lin et al identified activin A receptor type 1C polymor-phisms(rs4556933/rs77886248)as esophageal squamous cell carcinoma r...Two landmark studies demonstrate synergistic approaches to gastrointestinal cancer management.Lin et al identified activin A receptor type 1C polymor-phisms(rs4556933/rs77886248)as esophageal squamous cell carcinoma risk modifiers in Chinese Han populations through a case-control study(1264 patients/1361 controls),revealing transforming growth factor-beta pathway-mediated susceptibility in older male smokers(P<0.001).Concurrently,Luo et al established imaging-based differentiation of pancreatic cancer subtypes(pancreatic ductal adenocarcinoma vs neuroendocrine tumors)via retrospective analysis of 500 cases(area under the curve=0.89),enabling earlier intervention.These findings underscore the transformative potential of combining genetic risk stratification with advanced imaging to guide precision screening and therapeutic strategies,addressing critical gaps in esophageal and pancreatic cancer outcomes.展开更多
The variations in the mechanical and magnetic properties of cold-rolled 20Mn23AlV non-magnetic structural steel after annealing at different temperatures were investigated.The microstructure and precipitation changes ...The variations in the mechanical and magnetic properties of cold-rolled 20Mn23AlV non-magnetic structural steel after annealing at different temperatures were investigated.The microstructure and precipitation changes during annealing were studied by optical microscopy,scanning electron microscopy,and transmission electron microscopy.The results show that recrystallization completed after annealing at 620℃,resulting in grain sizes of approximately 800 nm and the best combination of strength and plasticity.The yield-to-tensile ratio of the non-magnetic structural steel after cold rolling continuously decreases from low to high temperatures after annealing,with the highest value being 0.89 and the lowest value being 0.43,indicating a wide range of yield-to-tensile ratio adjustment.The introduction of numerous dislocations during cold rolling provided favorable nucleation sites for precipitation,leading to abundant precipitation of the fine second-phase V(C,N).The phase composition of the samples remained unchanged as single-phase austenite after annealing,and the relative permeability values were calculated to be less than 1.002,meeting the requirements for non-magnetic steel in terms of magnetic properties.展开更多
Pd/Co_(2)MnSi(CMS)/Co/Pd multilayer films were designed based on the idea of combining highly spin-polarized materials with strong perpendicular magnetic anisotropy(PMA)films.The PMA of Pd/CMS/Co/Pd multilayer films w...Pd/Co_(2)MnSi(CMS)/Co/Pd multilayer films were designed based on the idea of combining highly spin-polarized materials with strong perpendicular magnetic anisotropy(PMA)films.The PMA of Pd/CMS/Co/Pd multilayer films was studied by optimizing the growth conditions and thickness of each film layer.The optimal structure of the multilayer films was Pd(6 nm)/CMS(5 nm)/Co(2 nm)/Pd(1 nm).Its abnormal Hall resistance(R_(Hall)),coercivity(H_(c))and effective magnetic anisotropy constant(Keff)are 0.08Ω,284 Oe and 1.36 Merg/cm^(3),respectively,which are 100%,492%,and 183%higher than the corresponding values(0.04Ω,48 Oe,and 0.48 Merg/cm^(3))of the Pd(6 nm)/Co(1 nm)/Pd(3 nm)trilayer films.The analysis shows that the increases of the above values are the result of the Pd/CMS interface effect and CMS/Co interface ferromagnetic(FM)coupling,and that it is closely related to the thickness of each film layer in the multilayer films and the growth conditions of the multilayer films.展开更多
基金supported by grants from The National Natural Science Foundation of China(31772690)the Natural Science Foundation of Shanxi Province(201701D121106)PhD Research Startup Foundation of Changzhi Medical College(BS202308)。
文摘Objective This study aimed to comprehensively investigate the potential protective effects and underlying mechanisms of taurine against dihydrotestosterone(DHT)-induced androgenetic alopecia(AGA)in male C57BL/6 mice,with a focus on hair follicle cycle modulation,cellular proliferation/apoptosis,and key related signaling pathways.Methods Six-week-old female C57BL/6 mice were initially used to assess the hair growth-promoting potential of taurine.After acclimatization,they were randomly assigned to three groups(n=8):control(regular drinking water),taurine(drinking water containing 1%taurine),and minoxidil(topical 2%minoxidil,positive control).For the AGA study,male C57BL/6 mice were randomly divided into five groups(n=8):control(physiological saline),DHT(model group,1 mg/d DHT),DHT+low-dose taurine(1 mg/d DHT+2 mg/d taurine),DHT+high-dose taurine(1 mg/d DHT+10 mg/d taurine),and DHT+minoxidil(positive control,1 mg/d DHT+topical 2%minoxidil).One day before treatment initiation,dorsal hair was shaved with scissors,and residual hair was removed using a depilatory cream.DHT and taurine were administered via daily intraperitoneal injection.Hair regrowth was assessed by photographing the depilated area at regular intervals and quantified using a four-point grading system(0-3).Dorsal skin samples were collected on day 14 for histological analysis(H&E staining),immunofluorescence staining(Ki67 for proliferation,TUNEL for apoptosis),ELISA(DHT quantification),RT-qPCR,and Western blot analysis to evaluate the expression of key genes and proteins(androgen receptor(AR),transforming growth factor(TGF)‑β1,TGF‑β2,Dickkopf-1(DKK1)).Results In female mice,taurine supplementation significantly accelerated hair growth,with effects comparable to minoxidil.This was evidenced by an earlier transition from pink(telogen)to black(anagen)skin and increased hair growth scores.Histological analysis showed that taurine increased hair follicle count and dermal thickness.Immunofluorescence confirmed enhanced keratinocyte proliferation in the hair matrix.In the DHTinduced AGA model,DHT significantly extended the telogen phase,inhibited hair growth,increased skin DHT content,and induced hair follicle miniaturization.Taurine treatment,particularly at the high dose,effectively counteracted these effects:it promoted the telogen-to-anagen transition and improved hair growth scores.Histomorphometric analysis showed that taurine significantly restored DHT-induced reductions in dermal thickness,hair follicle count,hair bulb depth,and follicle size.Taurine treatment also reduced apoptosis and promoted the proliferation of hair follicle cells,as demonstrated by Ki67 and TUNEL assays.Crucially,RT-qPCR and Western blot analyses revealed that DHT significantly up-regulated the expression of AR,TGF‑β1,TGF‑β2,and DKK1 at both mRNA and protein levels in dorsal skin.Taurine administration markedly down-regulated the expression of these pathogenic factors,bringing them closer to the levels observed in the control group.Conclusion Taurine demonstrates significant efficacy in alleviating DHT-induced AGA in male C57BL/6 mice.Its protective effects are mediated through multi-faceted mechanisms.(1)Promoting hair follicle cycle progression:it accelerates the transition from telogen to anagen,counteracting DHT-induced prolongation of the telogen phase.(2)Modulating cellular dynamics:it stimulates the proliferation of hair matrix keratinocytes and reduces DHT-induced apoptosis within hair follicle cells.(3)Suppressing androgen-driven pathogenic pathways:it downregulates the expression of critical molecules in the AGA pathway,including AR,the cytokines TGF-β1 and TGF-β2,and the Wnt pathway inhibitor DKK1.Given its favorable safety profile and multi-targeted action,taurine emerges as a promising novel therapeutic candidate or adjunct for treating AGA.Further investigation into its clinical potential and precise molecular mechanisms is warranted.This study provides a robust preclinical foundation for considering taurine supplementation or topical application in hair loss management strategies.
基金supported by the National Natural Science Foundation of China(Youth Science Fund Project),No.81901292(to GC)the National Key Research and Development Program of China,No.2021YFC2502100(to GC)the National Natural Science Foundation of China,No.82071183(to ZZ).
文摘Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function.Increasing amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers.These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases.Through a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.
基金National Key R&D Program of China,Grant/Award Number:2021YFF0703200Key Technology Fund of the National Institutes for Food and Drug Control,Grant/Award Number:GJJS-2022-1-5。
文摘Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is imperative to adhere to standardized experiments and controls.This paper objectively reviews the origin,differentiation,and phenotypic and genetic differences between the C57BL/6 and BALB/c mouse substrains.Furthermore,an optimal selection strategy is proposed based on the genetic quality control technology to facilitate the precise application of these two mouse substrains.
基金supported by the National Natural Science Foundation of China(32130013,32070434)the National Key Research and Development Program of China(2022YFC2601601)+1 种基金the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK05010112,2019QZKK0304-02)Hainan Tropical Rainforest Conservation Research Project,ZDYF2023RDYL01(supported by the Hainan Institute of National Park,HINP,KY-24ZK02).
文摘Understanding the genetic diversity–area relationship(GAR)is essential for comprehending how species adapt to environmental changes,as genetic diversity is an indicator of a species’adaptive potential.Variation in environmental adaptation capacity exists among species and animal taxa with different distribution areas,highlighting the importance of understanding the GAR.To obtain a more comprehensive understanding of the GAR in terrestrial vertebrates,we assessed both haplotype diversity–area and nucleotide diversity–area relationships using 25,453 cytochrome c oxidase subunit I(COI)sequences from 142 amphibian species,574 bird species,and 342 mammal species.We found that both measures of genetic diversity increased with species range size across major animal groups.Nevertheless,the GAR did not differ among animal groups,while haplotype diversity performed better than nucleotide diversity in profiling the GAR,as indicated by higher R2 values.The difference in the modeling fit may stem from the distinct biological and mathematical significance of nucleotide diversity and haplotype diversity.These results suggest that the GAR follows similar rules among different animal taxa.Furthermore,haplotype diversity may serve as a more reliable indicator for assessing the potential effects of area size changes on animal populations and provide better guidance for conserving genetic diversity.
基金supported by National Natural Science Foundation of China(Nos.52472194,52101243)Natural Science Foundation of Guangdong Province,China(No.2023A1515012619)the Science and Technology Planning Project of Guangzhou(No.202201010565)。
文摘The efficient limitation of the"shuttle effect"of polysulfide from the rational construction of electrocatalysts to accelerate the redox kinetics of polysulfides is extremely important.In this work,the cobalt/Nickel bimetallic alloy polyhedrons decorated on layered TiO_(2)heterostructure(Co Ni@TiO_(2)/C)derived from MXene and bimetallic metal-organic framework have been prepared through liquid-phase deposition and high-temperature annealing processes.This heterostructure presents excellent electrical conductivity,which facilitates ion diffusion and electron transfer within the battery.Besides,the heterostructure from anchoring the Co Ni bimetallic alloy on the layered TiO_(2)ensures the full exposure of active sites and accelerates polysulfide redox kinetics through chemisorption and catalytic conversion.Considering these advantages mentioned above,when applied as the lithium-sulfur batteries(LSBs)separator modifier,the cell assembled from the Co Ni@TiO_(2)/C modified separator demonstrates high specific capacity(1481.7 mAh/g at 0.5 C),superior rate capability(855.5 mAh/g at 3 C)and excellent cycling performance,which can maintain the high capacity of 856.09 mAh/g after 300 cycles with low capacity decay rate of 0.09%per cycle.Even under a high sulfur loading of 4.4 mg/cm^(2),the cell can still present excellent cycling stability.This study paves the way for the design of novel material for the construction of an outstanding functional separator layer and shines the light on the effective and feasible way for the inhibition of shuttle effect in lithium-sulfur batteries.
基金financially supported by the Shandong Provincial Natural Science Foundation(No.ZR2021QC182).
文摘Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most studies utilize gene knockout mice to explain the mechanisms.However,the production of genetically engineered mice is costly and time-consuming.In this study,we presented a convenient research strategy using an RNA interference(RNAi)and testicular transplantation approach.Histone H3 lysine 9(H3K9)methylation was dynamically regulated during spermatogenesis.As Jumonji domain-containing protein 1A(JMJD1A)and Jumonji domain-containing protein 2C(JMJD2C)demethylases catalyze histone H3 lysine 9 dimethylation(H3K9me2),we firstly analyzed the expression profile of the two demethylases and then investigated their function.Using the convenient research strategy,we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases.These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.
基金supported by the National Key Research and Development Program of China(No.2022YFC2303100)the National Natural Science Foundation of China(Nos.32022002 and 21977113).
文摘(±)-Penicithrones A–D(1a/1b–4a/4b),four novel pairs of anthrone–cyclopentenone heterodimers characterized by a distinctive bridged 6/6/6−5 tetracyclic core skeleton,together with three previously identified compounds(5–7),were isolated from the crude extract of the mangrove-derived fungus Penicillium sp.,guided by heteronuclear single quantum correlation(HSQC)-based small molecule accurate recognition technology(SMART 2.0)and liquid chromatography-tandem mass spectrometry(LC-MS/MS)-based molecular networking.The structural elucidation of new compounds was accomplished through comprehensive spectroscopic analysis,and their absolute configurations were determined using DP4+^(13)C nuclear magnetic resonance(NMR)calculations and electronic circular dichroism(ECD)calculations.Compounds 1a/1b–4a/4b demonstrated moderate cytotoxicity against three human cancer cell lines HeLa,HCT116 and MCF-7 with half maximal inhibitory concentration(IC50)values ranging from 15.95±1.64 to 28.56±2.59μmol·L–1.
文摘BACKGROUND Liver imaging and transient elastography(TE)are both tools used to assess liver fibrosis and steatosis among people with hepatitis C virus(HCV)infection.However,the diagnostic accuracy of conventional imaging in detecting fibrosis and steatosis in this patient population remains unclear.AIM To investigate the correlation between steatosis and fibrosis and abnormal findings on liver imaging in patients with HCV.METHODS We conducted a retrospective cross-sectional analysis of patients with HCV at Grady Liver Clinic who had TE exams between 2018-2019.We analyzed the correlation of controlled attenuation parameter and liver stiffness measurement on TE and abnormal findings on liver imaging.Liver imaging findings(hepatic steatosis,increased echogenicity,cirrhosis,and chronic liver disease)were further evaluated for their diagnostic performance in detecting fibrosis(≥F2,≥F3,≥F4)and steatosis(≥S1,≥S2,≥S3).RESULTS Of 959 HCV patients who underwent TE,651 had liver imaging.Higher controlled attenuation parameter scores were observed in patients with abnormal liver findings(P=0.0050),hepatic steatosis(P<0.0001),and increased echogenicity(P<0.0001).Higher liver stiffness measurement values were also noted in those with abnormal liver(P<0.0001)and increased echogenicity(P=0.0026).Steatosis severity correlated with hepatic steatosis(r=0.195,P<0.001)and increased echogenicity(r=0.209,P<0.001).For fibrosis detection,abnormal liver imaging had moderate sensitivity(81.7%)and specificity(70.4%)for cirrhosis(≥F4),while cirrhosis on imaging had high specificity(99.2%)but low sensitivity(18.3%).Increased echogenicity showed high specificity(92.8%)but low sensitivity(20.9%)for steatosis detection.CONCLUSION Liver imaging detects advanced fibrosis and steatosis but lacks early-stage sensitivity.Integrating TE with imaging may improve evaluation in patients with HCV.
基金supported by the National Natural Science Foundation of China(Grant No.52272263)the University Synergy Innovation Program of Anhui Province,China(Grant No.GXXT-2022-008)+2 种基金the University Natural Science Research Project of Anhui Province,China(Grant No.2024AH050145)the Youth Foundation of Anhui University of Technology(Grant No.QZ202303)the National Innovation and Entrepreneurship Training Program for College Students(Grant No.202310360018).
文摘This study investigated the effects of interstitial carbon doping on the microstructural and magnetocaloric properties of off-stoichiometric La_(1.2)Fe_(11.6)Si_(1.4)Cx(x=0,0.25,0.5,0.75,1)alloys.The alloys were prepared by melt-spinning following vacuum arc-melting.For the as-prepared and annealed samples,the carbon existed in the La_(2)Fe_(2)Si_(2)C and NaZn_(13)-type La(Fe,Si)_(13)(denoted by 1:13)phases,respectively.During the annealing process,the C atoms inhibited the diffusion reaction and depressed the generation of 1:13 phase,reducing mass fraction of the 1:13 phase in annealed La_(1.2)Fe_(11.6)Si_(1.4)Cx compounds.The introduction of carbon resulted in lattice expansion and increased the Curie temperature(T_(C))from 192 K to 273 K with x=0.5.The first-order magnetic transition was gradually transformed into the second-order magnetic transition with increasing carbon content,which induced the significant reduction of thermal and magnetic hysteresis,as well as the maximum magnetic entropy change and adiabatic temperature change vary from 18.92 J/(kg·K)to 4.60 J/(kg·K)and from 4.9 K to 2.2 K under an applied field change of 0-2 T.The results demonstrate that interstitial carbon doping is an effective strategy to improve the magnetocaloric performance of La(Fe,Si)_(13)alloys.
文摘Two landmark studies demonstrate synergistic approaches to gastrointestinal cancer management.Lin et al identified activin A receptor type 1C polymor-phisms(rs4556933/rs77886248)as esophageal squamous cell carcinoma risk modifiers in Chinese Han populations through a case-control study(1264 patients/1361 controls),revealing transforming growth factor-beta pathway-mediated susceptibility in older male smokers(P<0.001).Concurrently,Luo et al established imaging-based differentiation of pancreatic cancer subtypes(pancreatic ductal adenocarcinoma vs neuroendocrine tumors)via retrospective analysis of 500 cases(area under the curve=0.89),enabling earlier intervention.These findings underscore the transformative potential of combining genetic risk stratification with advanced imaging to guide precision screening and therapeutic strategies,addressing critical gaps in esophageal and pancreatic cancer outcomes.
基金support from the Gansu Province Science and Technology Major Project(22ZD6GA008)Commissioner for Science,Technology Program of China Gansu Province(23CXA0013)+1 种基金National Natural Science Foundation of China(NSFC)(52061022)Jiayuguan City Science and Technology Major Project of China Gansu Province(22-02).
文摘The variations in the mechanical and magnetic properties of cold-rolled 20Mn23AlV non-magnetic structural steel after annealing at different temperatures were investigated.The microstructure and precipitation changes during annealing were studied by optical microscopy,scanning electron microscopy,and transmission electron microscopy.The results show that recrystallization completed after annealing at 620℃,resulting in grain sizes of approximately 800 nm and the best combination of strength and plasticity.The yield-to-tensile ratio of the non-magnetic structural steel after cold rolling continuously decreases from low to high temperatures after annealing,with the highest value being 0.89 and the lowest value being 0.43,indicating a wide range of yield-to-tensile ratio adjustment.The introduction of numerous dislocations during cold rolling provided favorable nucleation sites for precipitation,leading to abundant precipitation of the fine second-phase V(C,N).The phase composition of the samples remained unchanged as single-phase austenite after annealing,and the relative permeability values were calculated to be less than 1.002,meeting the requirements for non-magnetic steel in terms of magnetic properties.
基金Project supported by Shandong Provincial Natural Science Foundation,China(Grant No.ZR2022ME059)。
文摘Pd/Co_(2)MnSi(CMS)/Co/Pd multilayer films were designed based on the idea of combining highly spin-polarized materials with strong perpendicular magnetic anisotropy(PMA)films.The PMA of Pd/CMS/Co/Pd multilayer films was studied by optimizing the growth conditions and thickness of each film layer.The optimal structure of the multilayer films was Pd(6 nm)/CMS(5 nm)/Co(2 nm)/Pd(1 nm).Its abnormal Hall resistance(R_(Hall)),coercivity(H_(c))and effective magnetic anisotropy constant(Keff)are 0.08Ω,284 Oe and 1.36 Merg/cm^(3),respectively,which are 100%,492%,and 183%higher than the corresponding values(0.04Ω,48 Oe,and 0.48 Merg/cm^(3))of the Pd(6 nm)/Co(1 nm)/Pd(3 nm)trilayer films.The analysis shows that the increases of the above values are the result of the Pd/CMS interface effect and CMS/Co interface ferromagnetic(FM)coupling,and that it is closely related to the thickness of each film layer in the multilayer films and the growth conditions of the multilayer films.
