As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive ima...As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future.展开更多
Diphenyl carbonate(DPC)is one of the versatile carbonates,and is often used for the production of polycarbonates.In recent years,the catalytic synthesis of DPC has become an important topic but the development of a hi...Diphenyl carbonate(DPC)is one of the versatile carbonates,and is often used for the production of polycarbonates.In recent years,the catalytic synthesis of DPC has become an important topic but the development of a highly active metal-free catalyst is a great challenge.Herein,a series of ionic liquids-SBA-15 hybrid catalysts with different functional groups have been developed for the synthesis of DPC under solventfree condition,which are effective and clean instead of the metal-containing catalysts.It is found that in the presence of[SBA-15-IL-OH]Br catalyst,methyl phenyl carbonate(MPC)conversion of 80.5%along with 99.6%DPC selectivity is achieved,the TOF value is thrice higher than the best value reported by using transition metal-based catalysts.Moreover,the catalyst displays remarkable stability and recyclability.This work provides a new idea to design and prepare eco-friendly catalysts in a broad range of applications for the green synthesis of carbonates.展开更多
Many tissues and organ systems have intrinsic regeneration capabilities that are largely driven and maintained by tissue-resident stem cell populations. In recent years, growing evidence has demonstrated that cellular...Many tissues and organ systems have intrinsic regeneration capabilities that are largely driven and maintained by tissue-resident stem cell populations. In recent years, growing evidence has demonstrated that cellular metabolic homeostasis plays a central role in mediating stem cell fate, tissue regeneration, and homeostasis. Thus, a thorough understanding of the mechanisms that regulate metabolic homeostasis in stem cells may contribute to our knowledge on how tissue homeostasis is maintained and provide novel insights for disease management. In this review, we summarize the known relationship between the regulation of metabolic homeostasis and molecular pathways in stem cells. We also discuss potential targets of metabolic homeostasis in disease therapy and describe the current limitations and future directions in the development of these novel therapeutic targets.展开更多
Signal transduction between different organs is crucial in the normal development of the human body. As an important medium for signal communication, exosomes can transfer important information, such as microRNAs(miRN...Signal transduction between different organs is crucial in the normal development of the human body. As an important medium for signal communication, exosomes can transfer important information, such as microRNAs(miRNAs), from donors to receptors.MiRNAs are known to fine-tune a variety of biological processes, including maxillofacial development; however, the underlying mechanism remains largely unknown. In the present study, transient apoptosis was found to be due to the expression of a miniature swine maxillofacial-specific miRNA, ssc-mir-133b. Upregulation of ssc-mir-133b resulted in robust apoptosis in primary dental mesenchymal cells in the maxillofacial region. Cell leukemia myeloid 1(Mcl-1) was verified as the functional target, which triggered further downstream activation of endogenous mitochondria-related apoptotic processes during tooth development.More importantly, mandible exosomes were responsible for the initial apoptosis signal. An animal study demonstrated that ectopic expression of ssc-mir-133 b resulted in failed tooth formation after 12 weeks of subcutaneous transplantation in nude mice. The tooth germ developed abnormally without the indispensable exosomal signals from the mandible.展开更多
Micrognathia is a severe craniofacial deformity affecting appearance and survival. Previous studies revealed that multiple factors involved in the osteogenesis of mandibular bone have contributed to micrognathia, but ...Micrognathia is a severe craniofacial deformity affecting appearance and survival. Previous studies revealed that multiple factors involved in the osteogenesis of mandibular bone have contributed to micrognathia, but concerned little on factors other than osteogenesis. In the current study, we found that ectopic activation of Fgf8 by Osr2-cre in the presumptive mesenchyme for masseter tendon in mice led to micrognathia, masseter regression, and the disrupted patterning and differentiation of masseter tendon. Since Myf5-cre;Rosa26R-Fgf8 mice exhibited the normal masseter and mandibular bone, the possibility that the micrognathia and masseter regression resulted directly from the over-expressed Fgf8 was excluded. Further investigation disclosed that a series of chondrogenic markers were ectopically activated in the developing Osr2-cre;Rosa26R-Fgf8 masseter tendon, while the mechanical sensing in the masseter and mandibular bone was obviously reduced. Thus, it suggested that the micrognathia in Osr2-cre;Rosa26R-Fgf8 mice resulted secondarily from the reduced mechanical force transmitted to mandibular bone. Consistently,when tenogenic or myogenic components were deleted from the developing mandibles, both the micrognathia and masseter degeneration took place with the decreased mechanical sensing in mandibular bone, which verified that the loss of mechanical force transmitted by masseter tendon could result in micrognathia. Furthermore, it appeared that the micrognathia resulting from the disrupted tenogenesis was attributed to the impaired osteogenic specification, instead of the differentiation in the periosteal progenitors. Our findings disclose a novel mechanism for mandibular morphogenesis, and shed light on the prevention and treatment for micrognathia.展开更多
Oxidized starch powder and cationic starch solution were reacted with alkyl ketene dimer(AKD) under heterogeneous conditions at 70℃ for 12 h.The AKD molecules reacted with starch hydroxyl groups to form β-keto ester...Oxidized starch powder and cationic starch solution were reacted with alkyl ketene dimer(AKD) under heterogeneous conditions at 70℃ for 12 h.The AKD molecules reacted with starch hydroxyl groups to form β-keto ester linkages under the above conditions.The reaction products were separated into CHCl_3-soluble and CHCl_3-insoluble fractions.FT-IR spectroscopy,SEM,Xray diffraction,and TG-DTA analyses of the CHCl_3-insoluble fraction indicated that β-keto ester substituents were introduced to hydroxyl groups on the starch surfaces.The results indicated that hydrogen bonds between the starch molecules were disrupted under heterogeneous conditions upon heating.The activity and accessibility of hydroxyl groups were enhanced,as a result of which β-keto ester bonds were produced between AKD and starch.Based on these results,we speculate that the β-keto esters which existed in the sheets sized by AKD emulsions were generated by the reaction between AKD and starch.展开更多
The burden of dental diseases is increasing in the Chinese population.However,the development of the dental industry falls behind the average development level of medical industry in China.The emergence of digital den...The burden of dental diseases is increasing in the Chinese population.However,the development of the dental industry falls behind the average development level of medical industry in China.The emergence of digital dental technologies has created significant opportunities for the development of the dental industry in China.This article explores the innovative development background of the Chinese dental industry,describes the current innovation status in Chinese medical colleges and enterprises,highlights key problems faced by the nation,enterprises,and hospitals,proposes solutions to these issues,and puts forwards a new concept of building an open and collaborative service system,a transformation path,and a whole-chain support system for innovations in dentistry.展开更多
Aging has a profound impact on the gingiva and significantly increases its susceptibility to periodontitis,a worldwide prevalent inflammatory disease.However,a systematic characterization and comprehensive understandi...Aging has a profound impact on the gingiva and significantly increases its susceptibility to periodontitis,a worldwide prevalent inflammatory disease.However,a systematic characterization and comprehensive understanding of the regulatory mechanism underlying gingival aging is still lacking.Here,we systematically dissected the phenotypic characteristics of gingiva during aging in primates and constructed the first single-nucleus transcriptomic landscape of gingival aging,by which a panel of cell type-specific signatures were elucidated.Epithelial cells were identified as the most affected cell types by aging in the gingiva.Further analyses pinpointed the crucial role of YAP in epithelial self-renew and homeostasis,which declined during aging in epithelial cells,especially in basal cells.The decline of YAP activity during aging was confrmed in the human gingival tissues,and downregulation of YAP in human primary gingival keratinocytes recapitulated the major phenotypic defects observed in the aged primate gingiva while overexpression of YAP showed rejuvenation effects.Our work provides an in-depth understanding of gingival aging and serves as a rich resource for developing novel strategies to combat aging-associated gingival diseases,with the ultimate goal of advancing periodontal health and promoting healthy aging.展开更多
The gingiva is a key oral barrier that protects oral tissues from various stimuli.A loss of gingival tissue homeostasis causes periodontitis,one of the most prevalent inflammatory diseases in humans.The human gingiva ...The gingiva is a key oral barrier that protects oral tissues from various stimuli.A loss of gingival tissue homeostasis causes periodontitis,one of the most prevalent inflammatory diseases in humans.The human gingiva exists as a complex cell network comprising specialized structures.To understand the tissue-specific pathophysiology of the gingiva,we applied a recently developed spatial enhanced resolution omics-sequencing(Stereo-seq)technique to obtain a spatial transcriptome(ST)atlas of the gingiva in healthy individuals and periodontitis patients.By utilizing Stereo-seq,we identified the major cell types present in the gingiva,which included epithelial cells,fibroblasts,endothelial cells,and immune cells,as well as subgroups of epithelial cells and immune cells.We further observed that inflammation-related signalling pathways,such as the JAK-STAT and NF-κB signalling pathways,were significantly upregulated in the endothelial cells of the gingiva of periodontitis patients compared with those of healthy individuals.Additionally,we characterized the spatial distribution of periodontitis risk genes in the gingiva and found that the expression of IFI16 was significantly increased in endothelial cells of inflamed gingiva.In conclusion,our Stereo-seq findings may facilitate the development of innovative therapeutic strategies for periodontitis by mapping periodontitis-relevant genes and pathways and effector cells.展开更多
Heat stress(HS)can cause a series of stress responses,resulting in numerous negative effects on the body,such as the diminished food intake,carcass quality and reproductive capacity.In addition to the negative effects...Heat stress(HS)can cause a series of stress responses,resulting in numerous negative effects on the body,such as the diminished food intake,carcass quality and reproductive capacity.In addition to the negative effects on the peripheral system,HS leads to central nervous system(CNS)disorders given its toll on neuroinflammation.This neuroinflammatory process is mainly mediated by microglia and astrocytes,which are involved in the activation of glial cells and the secretion of cytokines.While the regulation of inflammatory signaling has a close relationship with the expression of heat shock protein 70(Hsp70),HS-induced neuroinflammation is closely related to the activation of the TLR4/NF-κB pathway.Moreover,oxidative stress and endoplasmic reticulum(ER)stress are key players in the development of neuroinflammation.Chromium(Cr)has been widely shown to have neuroprotective effects in both humans and animals,despite the lack of mechanistic evidence.Evidence has shown that Cr supplementation can increase the levels of insulin-like growth factor 1(IGF-1),a major neurotrophic factor with anti-inflammatory and antioxidant effects.This review highlights recent advances in the attenuating effects and potential mechanisms of Cr-mediated IGF-1 actions on HS-induced neuroinflammation,providing presently existing evidence supporting the neuroprotective role of Cr.展开更多
Na Cl O has been widely used to restore membrane flux in practical membrane cleaning processes,which would induce the formation of toxic halogenated byproducts.In this study,we proposed a novel heatactivated peroxydis...Na Cl O has been widely used to restore membrane flux in practical membrane cleaning processes,which would induce the formation of toxic halogenated byproducts.In this study,we proposed a novel heatactivated peroxydisulfate(heat/PDS)process to clean the membrane fouling derived from humic acid(HA).The results show that the combination of heat and PDS can achieve almost 100%recovery of permeate flux after soaking the HA-fouled membrane in 1 mmol/L PDS solution at 50℃ for 2 h,which is attributed to the changes of HA structure and enhanced detachment of foulants from membranes.The properties of different treated membranes are characterized by scanning electron microscopy(SEM),atomic force microscope(AFM),attenuated total reflection Fourier transform infrared spectroscopy(ATRFTIR),and X-ray photoelectron spectroscopy(XPS),demonstrating that the reversible and irreversible foulants could be effectively removed by heat/PDS cleaning.The filtration process and fouling mechanism of the cleaned membrane were close to that of the virgin membrane,illustrating the good reusability of the cleaned membrane.Additionally,heat/PDS which can avoid the generation of halogenated byproducts shows comparable performance to Na Cl O on membrane cleaning and high performance for the removal of fouling caused by sodium alginate(SA),HA-bovine serum albumin(BSA)-SA mixture and algae,further suggesting that heat/PDS would be a potential alternative for membrane cleaning in practical application.展开更多
目的对比分析两种预防性回肠造口在腹腔镜经括约肌间切除术(Intershipincteric resection,ISR)治疗超低位直肠癌的效果。方法选取2019年6月至2022年6月接受腹腔镜ISR治疗的120例超低位直肠癌患者作为研究对象,采用随机数字表法将患者分...目的对比分析两种预防性回肠造口在腹腔镜经括约肌间切除术(Intershipincteric resection,ISR)治疗超低位直肠癌的效果。方法选取2019年6月至2022年6月接受腹腔镜ISR治疗的120例超低位直肠癌患者作为研究对象,采用随机数字表法将患者分为三针组和一针组,每组各60例。两组患者均于腹腔镜ISR后行预防性回肠造口术,三针组采取三针法,一针组采取一针法。数据应用软件SPSS 22.0处理。围手术期各项指标、疼痛评分、肛门失禁功能评分(Wexner)等计量资料采用x±s表示,行独立样本t检验或重复测量方差分析;术后并发症等计数资料采用[例(%)]表示,行χ^(2)或Fisher检验。P<0.05为差异有统计学意义。结果三针组手术时间及造口时间显著高于一针组(P<0.05),术后VAS评分显著低于一针组(P<0.05);两组患者术中出血量、肛门排气时间、术后住院时间及造口还纳术时间比较,差异无统计学意义(P>0.05)。两组患者术后均无吻合口漏的发生,但三针组术后造口相关并发症的总发生率显著低于一针组(6.7% vs. 20.0%,P<0.05),且术后造口脱垂的发生率显著低于一针组(0.0% vs. 10.0%,P<0.05)。两组患者经肛排便后均有不同程度的排便控制不佳、排便次数增多的情况,且随着时间推移,排便情况均有所好转,差异有统计学意义(P<0.05),但同一时间两组患者比较差异无统计学意义(P>0.05)。结论三针法和一针法预防性回肠造口术在腹腔镜ISR治疗超低位直肠癌中均是安全有效的,虽三针法预防性回肠造口术的手术时间及造口时间略有延长,但其可有效降低术后造口并发症发生的风险,尤其对减小术后造口脱垂的发生具有积极作用。展开更多
This study focuses on the application of the“PBL(problem-based learning)+Flipped Classroom”teaching model in bilingual education,aiming to explore its potential to enhance the quality and effectiveness of bilingual ...This study focuses on the application of the“PBL(problem-based learning)+Flipped Classroom”teaching model in bilingual education,aiming to explore its potential to enhance the quality and effectiveness of bilingual teaching.PBL emphasizes learning through the resolution of real-world problems,while the Flipped Classroom advocates that students acquire basic knowledge through self-study before class,dedicating class time to in-depth discussions and practical activities.The integration of these two teaching models in bilingual education aims to stimulate students’interest in learning,improve their autonomous learning abilities,enhance critical thinking,and foster cross-cultural communication skills.Through literature review,case analysis,and empirical research,this study first examines the current applications and challenges of PBL and the Flipped Classroom in bilingual education.Subsequently,it elaborates on the specific implementation steps of the“PBL+Flipped Classroom”teaching model in bilingual education,including problem design,preview material provision,cooperative learning,classroom activities,and language support.A comparative experiment is then conducted to analyze the impact of this teaching model on students’learning motivation,academic performance,and cross-cultural communication skills.The results indicate that the“PBL+Flipped Classroom”teaching model significantly improves students’learning motivation and participation,enhances academic performance,and effectively boosts their cross-cultural communication skills.Furthermore,this model aids in cultivating students’autonomous learning abilities and critical thinking,providing an innovative and effective approach to bilingual education.This study offers new ideas and insights for the field of bilingual education,which is of great significance for promoting the innovation and development of bilingual teaching models.展开更多
Although cisplatin is one of the chemotherapeutics most frequently used in oral squamous cell carcinoma(OSCC)treatment,it exerts multiple side effects and poor chemosensitivity.Nitrate reportedly demonstrates several ...Although cisplatin is one of the chemotherapeutics most frequently used in oral squamous cell carcinoma(OSCC)treatment,it exerts multiple side effects and poor chemosensitivity.Nitrate reportedly demonstrates several beneficial biological functions,and synthesized nitrates enhance the therapeutic efficacy of chemotherapy.However,the role of inorganic nitrate in cisplatin chemotherapy remains unclear.We therefore investigated the effect of inorganic nitrate exerted on cisplatin sensitivity in OSCC.We found that nitrate did not affect OSCC cell growth and apoptosis in OSCC cells and OSCC xenograft tumor animal studies.Cisplatin induced REDD1 expression and AKT activation in OSCC.However,nitrate could increase cisplatin chemosensitivity,reduce its REDD1 expression,and attenuate AKT signaling activation in OSCC cells.Dysregulation of high levels of REDD1,which could enhance AKT activation,was positively associated with poor prognosis in OSCC patients.Thus,reduced REDD1 expression and retarded AKT activation induced by inorganic nitrate might be a new potential approach to the sensitization of oral cancer to cisplatin treatment in the future.展开更多
Cellular senescence affects the efficacy of mesenchymal stem cells(MSCs)-mediated tissue regeneration.Insulin-like growth factor binding proteins-7(IGFBP7),as a member of the IGF family,is associated with osteogenic d...Cellular senescence affects the efficacy of mesenchymal stem cells(MSCs)-mediated tissue regeneration.Insulin-like growth factor binding proteins-7(IGFBP7),as a member of the IGF family,is associated with osteogenic differentiation and the senescence of MSCs,but its exact function and mechanism remain unclear.We found IGFBP7 promoted the osteogenic differentiation and prevented the senescence of dental pulp-derived MSCs(DPSCs),as observed in the gain-of-function and lossof-function analyses,the senescence-associated marker p21 showed the most pronounced expression changes.We demonstrated that IGFBP7 activated the biological activity of SIRT1 deacetylase via metabolism,resulting in a deacetylation of H3K36ac and a decrease of the binding affinity of H3K36ac to p21 promoter,thereby reducing the transcription of p21,which ultimately prevents DPSCs senescence and promotes tissue regeneration.The activation of the mitochondrial electron transport chain(ETC)by Coenzyme Q10 could rescue the promotion of DPSC senescence induced by the knockdown of IGFBP7,whereas the inhibition of ETC by rotenone attenuated the prevention of DPSC senescence induced by IGFBP7 overexpression.In conclusion,our present results reveal a novel function of IGFBP7 in preventing DPSC senescence via the metabolism-induced deacetylation of H3K36ac and reduction of p21 transcription,suggesting that IGFBP7 is a potential target for promoting tissue regeneration in an aging environment.展开更多
Senescence-related decline in liver function is a common complication in the elderly that can lead to impaired health in older individuals.Dietary nitrate supplements have physiological and therapeutic effects on orga...Senescence-related decline in liver function is a common complication in the elderly that can lead to impaired health in older individuals.Dietary nitrate supplements have physiological and therapeutic effects on organ function by nitrate(NO_3^-)-nitrite(NO_2^-)-nitric oxide(NO)pathway.However,the role of dietary nitrate on the senescence-related decline in liver function is unclear.The findings of the present study showed that nitrate levels in the serum and liver decreased,whereas the levels of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in serum increased in ageing mice.Consistently,cell senescence,decreased glycogen levels and increased lipid deposition were found in the liver of aged mice,both glucokinase(GCK)and phosphoenolpyruvate carboxykinase(PCK)were down-regulated(n=10).Daily nitrate intake(0.5 mmol L^(-1))restored nitrate levels,decreased ALT and AST levels,and prevented cell senescence and structural and glucose and lipid metabolism degeneration in liver tissue both in D-galactose(D-gal)-induced ageing mice(n=10)and in natural aged mice(n=10).In conclusion,the present study demonstrated that the reduction of nitrate levels was correlated with liver degeneration in ageing individuals and that dietary supplement of nitrate could restore the nitrate levels in serum and the liver and prevent ageing-related liver degeneration.展开更多
In this work,the removal of 2,4,6-tribromophenol(TBP)by ferric ion-activated sulfite[Fe(Ⅲ)/S(Ⅳ)]process was systematically investigated with determining the intermediate products and evaluating the influences of som...In this work,the removal of 2,4,6-tribromophenol(TBP)by ferric ion-activated sulfite[Fe(Ⅲ)/S(Ⅳ)]process was systematically investigated with determining the intermediate products and evaluating the influences of some operational conditions and water matrices.Our results show that batching addition of S(Ⅳ)benefits the S(Ⅳ)utilization efficiency and TBP removal,with SO_(4)^(-)being the primary reactive radical accounting for TBA degradation.The maximum TBP removal in the Fe(Ⅲ)/S(Ⅳ)process was observed at pH 4.0 and oxygen is essential in this process.With increasing Fe(Ⅲ)and S(Ⅳ)dosages from 0.05 and 0.1 mmol/L to 0.2 and 2.0 mmol/L,respectively,TBP removal followed trends of first increase then decrease.As the acute toxicity of the TBP solution was significantly reduced,the Fe(Ⅲ)/S(Ⅳ)process was believed to be a good choice in the treatment of TBP.展开更多
Current status data often arise in survival analysis and reliability studies, when a continuous response is reduced to an indicator of whether the response is greater or less than an observed random threshold value. T...Current status data often arise in survival analysis and reliability studies, when a continuous response is reduced to an indicator of whether the response is greater or less than an observed random threshold value. This article considers a partial linear model with current status data. A sieve least squares estimator is proposed to estimate both the regression parameters and the nonparametric function. This paper shows, under some mild condition, that the estimators are strong consistent. Moreover, the parameter estimators are normally distributed, while the nonparametric component achieves the optimal convergence rate. Simulation studies are carried out to investigate the performance of the proposed estimates. For illustration purposes, the method is applied to a real dataset from a study of the calcification of the hydrogel intraocular lenses, a complication of cataract treatment.展开更多
基金Project supported by the National Key R&D Program of China (Grant Nos.2023YFC2206502 and 2021YFA1600703)the National Natural Science Foundation of China (Grant Nos.12175254 and 12227810)the Guangdong–Hong Kong–Macao Joint Laboratory for Neutron Scattering Science and Technology。
文摘As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future.
基金support from the National Natural Science Foundation of China(No.21808048 and U1704251)Training Plan for University's Young Backbone Teachers of Henan Province(2021GGJS121)+5 种基金Program for Science&Technology Innovation Talents in Universities of Henan Province(23HASTIT014)Postgraduate Education Reform and Quality Improvement Project of Henan Province(YJS2022KC22)Project funded by China Postdoctoral Science Foundation(No.2018M632782)Project funded by Postdoctoral Research Grant in Henan Province(No.001802030)Key Project of Science and Technology Program of Henan Province(No.222102230109,212102310330 and 182102210050)the Science Research Start-up Fund of Henan Institute of Science and Technology(No.2015031).
文摘Diphenyl carbonate(DPC)is one of the versatile carbonates,and is often used for the production of polycarbonates.In recent years,the catalytic synthesis of DPC has become an important topic but the development of a highly active metal-free catalyst is a great challenge.Herein,a series of ionic liquids-SBA-15 hybrid catalysts with different functional groups have been developed for the synthesis of DPC under solventfree condition,which are effective and clean instead of the metal-containing catalysts.It is found that in the presence of[SBA-15-IL-OH]Br catalyst,methyl phenyl carbonate(MPC)conversion of 80.5%along with 99.6%DPC selectivity is achieved,the TOF value is thrice higher than the best value reported by using transition metal-based catalysts.Moreover,the catalyst displays remarkable stability and recyclability.This work provides a new idea to design and prepare eco-friendly catalysts in a broad range of applications for the green synthesis of carbonates.
基金the National Natural Science Foundation of China(82030031,L2224038,92149301)Chinese Academy of Medical Sciences Research Unit(2019-12M-5-031)+4 种基金Beijing Municipal Science&Technology Commission(Z181100001718208)Beijing Municipal Education Commission(119207020201)Beijing Municipality Government Grants(Beijing Laboratory of Oral Health-PXM2021_014226_000041,Beijing Scholar Program-PXM2021_014226_000020)Innovation Research Team Project of Beijing Stomatological Hospital,Capital Medical University(CXTD202201)Young Scientist Program of Beijing Stomatological Hospital,Capital Medical University(YSP202308).
文摘Many tissues and organ systems have intrinsic regeneration capabilities that are largely driven and maintained by tissue-resident stem cell populations. In recent years, growing evidence has demonstrated that cellular metabolic homeostasis plays a central role in mediating stem cell fate, tissue regeneration, and homeostasis. Thus, a thorough understanding of the mechanisms that regulate metabolic homeostasis in stem cells may contribute to our knowledge on how tissue homeostasis is maintained and provide novel insights for disease management. In this review, we summarize the known relationship between the regulation of metabolic homeostasis and molecular pathways in stem cells. We also discuss potential targets of metabolic homeostasis in disease therapy and describe the current limitations and future directions in the development of these novel therapeutic targets.
基金supported by the National Natural Science Foundation of China (No. 91649124 to S.W. No. 81371108 and 81670955 to A.L. and No. 81701037 to Y.L.)+1 种基金Beijing Municipality Government grants (Beijing Scholar ProgramPXM2016_014226_000006, PXM2016_014226_000034, PXM2015_014226_000052, PXM2015_014226_000055, PXM2015_014226_000116, PXM2014_014226_000013, PXM2014_014226_000048, PXM2014_014226_000053, Z121100005212004, PXM2013_014226_000021, PXM2013_014226_000055, PXM 2013_014226_07_ 000080 and TJSHG201310025005 to S.W.)an Open grant from Capital Medical University (No. KFKT2016005 to Y.L.)
文摘Signal transduction between different organs is crucial in the normal development of the human body. As an important medium for signal communication, exosomes can transfer important information, such as microRNAs(miRNAs), from donors to receptors.MiRNAs are known to fine-tune a variety of biological processes, including maxillofacial development; however, the underlying mechanism remains largely unknown. In the present study, transient apoptosis was found to be due to the expression of a miniature swine maxillofacial-specific miRNA, ssc-mir-133b. Upregulation of ssc-mir-133b resulted in robust apoptosis in primary dental mesenchymal cells in the maxillofacial region. Cell leukemia myeloid 1(Mcl-1) was verified as the functional target, which triggered further downstream activation of endogenous mitochondria-related apoptotic processes during tooth development.More importantly, mandible exosomes were responsible for the initial apoptosis signal. An animal study demonstrated that ectopic expression of ssc-mir-133 b resulted in failed tooth formation after 12 weeks of subcutaneous transplantation in nude mice. The tooth germ developed abnormally without the indispensable exosomal signals from the mandible.
基金supported by the grants from the National Natural Science Foundation of China(81970922 to J.X.and 81771055 to C.L.)。
文摘Micrognathia is a severe craniofacial deformity affecting appearance and survival. Previous studies revealed that multiple factors involved in the osteogenesis of mandibular bone have contributed to micrognathia, but concerned little on factors other than osteogenesis. In the current study, we found that ectopic activation of Fgf8 by Osr2-cre in the presumptive mesenchyme for masseter tendon in mice led to micrognathia, masseter regression, and the disrupted patterning and differentiation of masseter tendon. Since Myf5-cre;Rosa26R-Fgf8 mice exhibited the normal masseter and mandibular bone, the possibility that the micrognathia and masseter regression resulted directly from the over-expressed Fgf8 was excluded. Further investigation disclosed that a series of chondrogenic markers were ectopically activated in the developing Osr2-cre;Rosa26R-Fgf8 masseter tendon, while the mechanical sensing in the masseter and mandibular bone was obviously reduced. Thus, it suggested that the micrognathia in Osr2-cre;Rosa26R-Fgf8 mice resulted secondarily from the reduced mechanical force transmitted to mandibular bone. Consistently,when tenogenic or myogenic components were deleted from the developing mandibles, both the micrognathia and masseter degeneration took place with the decreased mechanical sensing in mandibular bone, which verified that the loss of mechanical force transmitted by masseter tendon could result in micrognathia. Furthermore, it appeared that the micrognathia resulting from the disrupted tenogenesis was attributed to the impaired osteogenic specification, instead of the differentiation in the periosteal progenitors. Our findings disclose a novel mechanism for mandibular morphogenesis, and shed light on the prevention and treatment for micrognathia.
基金financial support from Shandong Province Education Department(Grant No.J14 LC11)National Natural Science Foundation of China(Grant No.21406126 and 21576146)+2 种基金Department of Science and Technology of Shandong Province(Grant No.2014 GSF116001)973(Grant No.2014 CB460610)Department of Science and Technology of Shandong Province(Grant No.2015 ZDXX0403 B03)
文摘Oxidized starch powder and cationic starch solution were reacted with alkyl ketene dimer(AKD) under heterogeneous conditions at 70℃ for 12 h.The AKD molecules reacted with starch hydroxyl groups to form β-keto ester linkages under the above conditions.The reaction products were separated into CHCl_3-soluble and CHCl_3-insoluble fractions.FT-IR spectroscopy,SEM,Xray diffraction,and TG-DTA analyses of the CHCl_3-insoluble fraction indicated that β-keto ester substituents were introduced to hydroxyl groups on the starch surfaces.The results indicated that hydrogen bonds between the starch molecules were disrupted under heterogeneous conditions upon heating.The activity and accessibility of hydroxyl groups were enhanced,as a result of which β-keto ester bonds were produced between AKD and starch.Based on these results,we speculate that the β-keto esters which existed in the sheets sized by AKD emulsions were generated by the reaction between AKD and starch.
文摘The burden of dental diseases is increasing in the Chinese population.However,the development of the dental industry falls behind the average development level of medical industry in China.The emergence of digital dental technologies has created significant opportunities for the development of the dental industry in China.This article explores the innovative development background of the Chinese dental industry,describes the current innovation status in Chinese medical colleges and enterprises,highlights key problems faced by the nation,enterprises,and hospitals,proposes solutions to these issues,and puts forwards a new concept of building an open and collaborative service system,a transformation path,and a whole-chain support system for innovations in dentistry.
文摘Aging has a profound impact on the gingiva and significantly increases its susceptibility to periodontitis,a worldwide prevalent inflammatory disease.However,a systematic characterization and comprehensive understanding of the regulatory mechanism underlying gingival aging is still lacking.Here,we systematically dissected the phenotypic characteristics of gingiva during aging in primates and constructed the first single-nucleus transcriptomic landscape of gingival aging,by which a panel of cell type-specific signatures were elucidated.Epithelial cells were identified as the most affected cell types by aging in the gingiva.Further analyses pinpointed the crucial role of YAP in epithelial self-renew and homeostasis,which declined during aging in epithelial cells,especially in basal cells.The decline of YAP activity during aging was confrmed in the human gingival tissues,and downregulation of YAP in human primary gingival keratinocytes recapitulated the major phenotypic defects observed in the aged primate gingiva while overexpression of YAP showed rejuvenation effects.Our work provides an in-depth understanding of gingival aging and serves as a rich resource for developing novel strategies to combat aging-associated gingival diseases,with the ultimate goal of advancing periodontal health and promoting healthy aging.
基金supported by the National Natural Science Foundation of China(82201011,82030031,92149301 and 82270945)the Beijing Municipal Government grant(Beijing Laboratory of Oral Health,PXM2021-014226-000041)+2 种基金the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2019-I2M-5-038)the Science and Technology Project of Guangzhou,China(202206080009)the Postdoctoral Foundation of China(2021M703695 and 2021TQ0308)。
文摘The gingiva is a key oral barrier that protects oral tissues from various stimuli.A loss of gingival tissue homeostasis causes periodontitis,one of the most prevalent inflammatory diseases in humans.The human gingiva exists as a complex cell network comprising specialized structures.To understand the tissue-specific pathophysiology of the gingiva,we applied a recently developed spatial enhanced resolution omics-sequencing(Stereo-seq)technique to obtain a spatial transcriptome(ST)atlas of the gingiva in healthy individuals and periodontitis patients.By utilizing Stereo-seq,we identified the major cell types present in the gingiva,which included epithelial cells,fibroblasts,endothelial cells,and immune cells,as well as subgroups of epithelial cells and immune cells.We further observed that inflammation-related signalling pathways,such as the JAK-STAT and NF-κB signalling pathways,were significantly upregulated in the endothelial cells of the gingiva of periodontitis patients compared with those of healthy individuals.Additionally,we characterized the spatial distribution of periodontitis risk genes in the gingiva and found that the expression of IFI16 was significantly increased in endothelial cells of inflamed gingiva.In conclusion,our Stereo-seq findings may facilitate the development of innovative therapeutic strategies for periodontitis by mapping periodontitis-relevant genes and pathways and effector cells.
基金financially supported by the National Natural Science Foundation of China(No.32272967).
文摘Heat stress(HS)can cause a series of stress responses,resulting in numerous negative effects on the body,such as the diminished food intake,carcass quality and reproductive capacity.In addition to the negative effects on the peripheral system,HS leads to central nervous system(CNS)disorders given its toll on neuroinflammation.This neuroinflammatory process is mainly mediated by microglia and astrocytes,which are involved in the activation of glial cells and the secretion of cytokines.While the regulation of inflammatory signaling has a close relationship with the expression of heat shock protein 70(Hsp70),HS-induced neuroinflammation is closely related to the activation of the TLR4/NF-κB pathway.Moreover,oxidative stress and endoplasmic reticulum(ER)stress are key players in the development of neuroinflammation.Chromium(Cr)has been widely shown to have neuroprotective effects in both humans and animals,despite the lack of mechanistic evidence.Evidence has shown that Cr supplementation can increase the levels of insulin-like growth factor 1(IGF-1),a major neurotrophic factor with anti-inflammatory and antioxidant effects.This review highlights recent advances in the attenuating effects and potential mechanisms of Cr-mediated IGF-1 actions on HS-induced neuroinflammation,providing presently existing evidence supporting the neuroprotective role of Cr.
基金supported by the Natural Science Foundation of China(Nos.52070081,51578258 and 51878308)the National Key Research and Development Program of China(No.2022YFC3203500)。
文摘Na Cl O has been widely used to restore membrane flux in practical membrane cleaning processes,which would induce the formation of toxic halogenated byproducts.In this study,we proposed a novel heatactivated peroxydisulfate(heat/PDS)process to clean the membrane fouling derived from humic acid(HA).The results show that the combination of heat and PDS can achieve almost 100%recovery of permeate flux after soaking the HA-fouled membrane in 1 mmol/L PDS solution at 50℃ for 2 h,which is attributed to the changes of HA structure and enhanced detachment of foulants from membranes.The properties of different treated membranes are characterized by scanning electron microscopy(SEM),atomic force microscope(AFM),attenuated total reflection Fourier transform infrared spectroscopy(ATRFTIR),and X-ray photoelectron spectroscopy(XPS),demonstrating that the reversible and irreversible foulants could be effectively removed by heat/PDS cleaning.The filtration process and fouling mechanism of the cleaned membrane were close to that of the virgin membrane,illustrating the good reusability of the cleaned membrane.Additionally,heat/PDS which can avoid the generation of halogenated byproducts shows comparable performance to Na Cl O on membrane cleaning and high performance for the removal of fouling caused by sodium alginate(SA),HA-bovine serum albumin(BSA)-SA mixture and algae,further suggesting that heat/PDS would be a potential alternative for membrane cleaning in practical application.
文摘目的对比分析两种预防性回肠造口在腹腔镜经括约肌间切除术(Intershipincteric resection,ISR)治疗超低位直肠癌的效果。方法选取2019年6月至2022年6月接受腹腔镜ISR治疗的120例超低位直肠癌患者作为研究对象,采用随机数字表法将患者分为三针组和一针组,每组各60例。两组患者均于腹腔镜ISR后行预防性回肠造口术,三针组采取三针法,一针组采取一针法。数据应用软件SPSS 22.0处理。围手术期各项指标、疼痛评分、肛门失禁功能评分(Wexner)等计量资料采用x±s表示,行独立样本t检验或重复测量方差分析;术后并发症等计数资料采用[例(%)]表示,行χ^(2)或Fisher检验。P<0.05为差异有统计学意义。结果三针组手术时间及造口时间显著高于一针组(P<0.05),术后VAS评分显著低于一针组(P<0.05);两组患者术中出血量、肛门排气时间、术后住院时间及造口还纳术时间比较,差异无统计学意义(P>0.05)。两组患者术后均无吻合口漏的发生,但三针组术后造口相关并发症的总发生率显著低于一针组(6.7% vs. 20.0%,P<0.05),且术后造口脱垂的发生率显著低于一针组(0.0% vs. 10.0%,P<0.05)。两组患者经肛排便后均有不同程度的排便控制不佳、排便次数增多的情况,且随着时间推移,排便情况均有所好转,差异有统计学意义(P<0.05),但同一时间两组患者比较差异无统计学意义(P>0.05)。结论三针法和一针法预防性回肠造口术在腹腔镜ISR治疗超低位直肠癌中均是安全有效的,虽三针法预防性回肠造口术的手术时间及造口时间略有延长,但其可有效降低术后造口并发症发生的风险,尤其对减小术后造口脱垂的发生具有积极作用。
基金Quality Engineering Project of Chuzhou University“A Study on the Application of the‘PBL+Flipped Classroom’Teaching Mode Integrated with Rain Classroom in Bilingual Teaching of International Enterprise Management”(2022jyc047)Scientific Research Projects of Higher Education Institutions in Anhui Province“Research on the Mechanism of Enabling the Dual-Chain Integration of‘Industry Chain–Talent Chain’in Anhui through New Quality Productivity”(2024AH052932)+1 种基金Education Science Planning Project of Jiangsu Province“Research on the Reform of Practical Teaching in Open Universities under Digital Transformation”(C/2023/01/126)Project of Social Science Foundation of Jiangsu Province“Research on the Path and Mechanism of Digital Empowerment for the Integration of‘Industry Chain-Talent Chain’in Jiangsu”(23GLD002)。
文摘This study focuses on the application of the“PBL(problem-based learning)+Flipped Classroom”teaching model in bilingual education,aiming to explore its potential to enhance the quality and effectiveness of bilingual teaching.PBL emphasizes learning through the resolution of real-world problems,while the Flipped Classroom advocates that students acquire basic knowledge through self-study before class,dedicating class time to in-depth discussions and practical activities.The integration of these two teaching models in bilingual education aims to stimulate students’interest in learning,improve their autonomous learning abilities,enhance critical thinking,and foster cross-cultural communication skills.Through literature review,case analysis,and empirical research,this study first examines the current applications and challenges of PBL and the Flipped Classroom in bilingual education.Subsequently,it elaborates on the specific implementation steps of the“PBL+Flipped Classroom”teaching model in bilingual education,including problem design,preview material provision,cooperative learning,classroom activities,and language support.A comparative experiment is then conducted to analyze the impact of this teaching model on students’learning motivation,academic performance,and cross-cultural communication skills.The results indicate that the“PBL+Flipped Classroom”teaching model significantly improves students’learning motivation and participation,enhances academic performance,and effectively boosts their cross-cultural communication skills.Furthermore,this model aids in cultivating students’autonomous learning abilities and critical thinking,providing an innovative and effective approach to bilingual education.This study offers new ideas and insights for the field of bilingual education,which is of great significance for promoting the innovation and development of bilingual teaching models.
基金This work was supported by the CAMS Innovation Fund for Medical Sciences(2019-I2M-5-031)Beijing Hospitals Authority of Hospitals’Mission Plan(SML20151401,Capital Medical University)+1 种基金Beijing Municipality Government grants(Beijing Scholar Program—PXM2020_014226_000005,PXM2019_014226_000039,PXM2019_014226_000011,PXM2018_014226_000021,PXM2017_014226_000023,PXM2018_193312_000006_0028S643_FCG,PXM2016_014226_000034)the National Natural Science Foundation of China(91649124).
文摘Although cisplatin is one of the chemotherapeutics most frequently used in oral squamous cell carcinoma(OSCC)treatment,it exerts multiple side effects and poor chemosensitivity.Nitrate reportedly demonstrates several beneficial biological functions,and synthesized nitrates enhance the therapeutic efficacy of chemotherapy.However,the role of inorganic nitrate in cisplatin chemotherapy remains unclear.We therefore investigated the effect of inorganic nitrate exerted on cisplatin sensitivity in OSCC.We found that nitrate did not affect OSCC cell growth and apoptosis in OSCC cells and OSCC xenograft tumor animal studies.Cisplatin induced REDD1 expression and AKT activation in OSCC.However,nitrate could increase cisplatin chemosensitivity,reduce its REDD1 expression,and attenuate AKT signaling activation in OSCC cells.Dysregulation of high levels of REDD1,which could enhance AKT activation,was positively associated with poor prognosis in OSCC patients.Thus,reduced REDD1 expression and retarded AKT activation induced by inorganic nitrate might be a new potential approach to the sensitization of oral cancer to cisplatin treatment in the future.
基金the National Natural Science Foundation of China(82030031,81991504,92149301,82001067)the Chinese Research Unit of Tooth Development and Regeneration,Academy of Medical Sciences(2019-12M-5-031)+7 种基金the Beijing Municipal Science and Technology Commission(Z181100001718208)the Beijing Municipal Education Commission(119207020201)Beijing Advanced Innovation Center for Big Data-based Precision Medicine(PXM2021_014226_000026)the Beijing Municipal Government(Beijing Scholar program PXM2020_014226_000005,PXM2021_014226_000020)Innovation Research Team Project of Beijing Stomatological Hospital,Capital Medical University(CXTD202201)Beijing Municipal Administration of Hospitals’Youth Program(QML20191504)Scientific Research Common Program of Beijing Municipal Commission of Education(KM202110025009)Beijing Talents Fund(2018000021469G285)。
文摘Cellular senescence affects the efficacy of mesenchymal stem cells(MSCs)-mediated tissue regeneration.Insulin-like growth factor binding proteins-7(IGFBP7),as a member of the IGF family,is associated with osteogenic differentiation and the senescence of MSCs,but its exact function and mechanism remain unclear.We found IGFBP7 promoted the osteogenic differentiation and prevented the senescence of dental pulp-derived MSCs(DPSCs),as observed in the gain-of-function and lossof-function analyses,the senescence-associated marker p21 showed the most pronounced expression changes.We demonstrated that IGFBP7 activated the biological activity of SIRT1 deacetylase via metabolism,resulting in a deacetylation of H3K36ac and a decrease of the binding affinity of H3K36ac to p21 promoter,thereby reducing the transcription of p21,which ultimately prevents DPSCs senescence and promotes tissue regeneration.The activation of the mitochondrial electron transport chain(ETC)by Coenzyme Q10 could rescue the promotion of DPSC senescence induced by the knockdown of IGFBP7,whereas the inhibition of ETC by rotenone attenuated the prevention of DPSC senescence induced by IGFBP7 overexpression.In conclusion,our present results reveal a novel function of IGFBP7 in preventing DPSC senescence via the metabolism-induced deacetylation of H3K36ac and reduction of p21 transcription,suggesting that IGFBP7 is a potential target for promoting tissue regeneration in an aging environment.
基金supported by the National Natural Science Foundation of China (91649124)Beijing Municipality Government grants (Beijing Scholar Program- PXM2016_014226_000034, PXM2016_014226_000006, PXM2015_014226_000116, PXM2015_ 014226_000055, PXM2015_014226_000052, PXM2014_014226_000048, PXM2014_014226_000013, PXM2014_014226_000053, Z121100005212004, PXM2013_014226_000055, PXM2013_014226_000021, PXM 2013_014226_07_000080, TJSHG201310025005)
文摘Senescence-related decline in liver function is a common complication in the elderly that can lead to impaired health in older individuals.Dietary nitrate supplements have physiological and therapeutic effects on organ function by nitrate(NO_3^-)-nitrite(NO_2^-)-nitric oxide(NO)pathway.However,the role of dietary nitrate on the senescence-related decline in liver function is unclear.The findings of the present study showed that nitrate levels in the serum and liver decreased,whereas the levels of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in serum increased in ageing mice.Consistently,cell senescence,decreased glycogen levels and increased lipid deposition were found in the liver of aged mice,both glucokinase(GCK)and phosphoenolpyruvate carboxykinase(PCK)were down-regulated(n=10).Daily nitrate intake(0.5 mmol L^(-1))restored nitrate levels,decreased ALT and AST levels,and prevented cell senescence and structural and glucose and lipid metabolism degeneration in liver tissue both in D-galactose(D-gal)-induced ageing mice(n=10)and in natural aged mice(n=10).In conclusion,the present study demonstrated that the reduction of nitrate levels was correlated with liver degeneration in ageing individuals and that dietary supplement of nitrate could restore the nitrate levels in serum and the liver and prevent ageing-related liver degeneration.
基金The support by the National Natural Science Foundation of China(No.51878308)the Young Top-notch Talent Cultivation Program of Hubei Province。
文摘In this work,the removal of 2,4,6-tribromophenol(TBP)by ferric ion-activated sulfite[Fe(Ⅲ)/S(Ⅳ)]process was systematically investigated with determining the intermediate products and evaluating the influences of some operational conditions and water matrices.Our results show that batching addition of S(Ⅳ)benefits the S(Ⅳ)utilization efficiency and TBP removal,with SO_(4)^(-)being the primary reactive radical accounting for TBA degradation.The maximum TBP removal in the Fe(Ⅲ)/S(Ⅳ)process was observed at pH 4.0 and oxygen is essential in this process.With increasing Fe(Ⅲ)and S(Ⅳ)dosages from 0.05 and 0.1 mmol/L to 0.2 and 2.0 mmol/L,respectively,TBP removal followed trends of first increase then decrease.As the acute toxicity of the TBP solution was significantly reduced,the Fe(Ⅲ)/S(Ⅳ)process was believed to be a good choice in the treatment of TBP.
基金This research is supported in part by the National Natural Science Foundation of. China under Grant No. 10801133.
文摘Current status data often arise in survival analysis and reliability studies, when a continuous response is reduced to an indicator of whether the response is greater or less than an observed random threshold value. This article considers a partial linear model with current status data. A sieve least squares estimator is proposed to estimate both the regression parameters and the nonparametric function. This paper shows, under some mild condition, that the estimators are strong consistent. Moreover, the parameter estimators are normally distributed, while the nonparametric component achieves the optimal convergence rate. Simulation studies are carried out to investigate the performance of the proposed estimates. For illustration purposes, the method is applied to a real dataset from a study of the calcification of the hydrogel intraocular lenses, a complication of cataract treatment.
