[Objectives]To explore the hypoglycemic effect of Radix Et Rhizoma Salviae Miltiorrhizae,Guixi green tea and their compatibility on mice,so as to provide more options for the adjuvant treatment of diabetes and improve...[Objectives]To explore the hypoglycemic effect of Radix Et Rhizoma Salviae Miltiorrhizae,Guixi green tea and their compatibility on mice,so as to provide more options for the adjuvant treatment of diabetes and improve the comprehensive utilization value of Guixi green tea.[Methods]After being fed adaptively for 7 d,60 SPF-grade male mice were intraperitoneally injected with alloxouracil(180 mg/kg)to induce hyperglycemia model,from which 35 mice with a successful model were selected.They were randomly divided into 5 groups(Danshen group,green tea group,compatible group,positive control group and blank control group),with 7 animals in each group.The mice in all groups were administered according to the dose of 200 mg/kg once a day for 15 d.After the last administration,their body weight was measured on the 15 th day after fasting for 12 h,and their fasting blood glucose was measured by tail clipping.[Results]After modeling,the mice in each group showed typical hyperglycemia symptoms,namely obvious polydipsia,polyphagia,polyuria and weight loss.Compared with the blank control group,Danshen group and green tea group had obvious hypoglycemic effect(P<0.05),and compatible group had significant hypoglycemic effect(P<0.01).Compared with the blank control group,the weight loss of diabetic mice could also be inhibited in green tea group and compatible group(P<0.05).[Conclusions]Danshen,Guixi green tea and their compatibility had the effect of lowering blood sugar,among which the compatible group had the most obvious effect.展开更多
Developed regions of the world represent a major atmospheric methane(CH_4) source,but these regional emissions remain poorly constrained.The Yangtze River Delta(YRD) region of China is densely populated(about 16% of C...Developed regions of the world represent a major atmospheric methane(CH_4) source,but these regional emissions remain poorly constrained.The Yangtze River Delta(YRD) region of China is densely populated(about 16% of China's total population) and consists of large anthropogenic and natural CH_4 sources.Here,atmospheric CH_4 concentrations measured at a 70-m tall tower in the YRD are combined with a scale factor Bayesian inverse(SFBI) modeling approach to constrain seasonal variations in CH_4 emissions.Results indicate that in 2018 agricultural soils(AGS,rice production) were the main driver of seasonal variability in atmospheric CH_4 concentration.There was an underestimation of emissions from AGS in the a priori inventories(EDGAR—Emissions Database for Global Atmospheric Research v432 or v50),especially during the growing seasons.Posteriori CH_4 emissions from AGS accounted for 39%(4.58 Tg,EDGAR v432) to 47%(5.21 Tg,EDGAR v50) of the total CH_4 emissions.The posteriori natural emissions(including wetlands and water bodies) were1.21 Tg and 1.06 Tg,accounting for 10.1%(EDGAR v432) and 9.5%(EDGAR v50) of total emissions in the YRD in2018.Results show that the dominant factor for seasonal variations in atmospheric concentration in the YRD was AGS,followed by natural sources.In summer,AGS contributed 42%(EDGAR v432) to 64%(EDGAR v50) of the CH_4 concentration enhancement while natural sources only contributed about 10%(EDGAR v50) to 15%(EDGAR v432).In addition,the newer version of the EDGAR product(EDGAR v50) provided more reasonable seasonal distribution of CH_4 emissions from rice cultivation than the old version(EDGAR v432).展开更多
Escherichia coli has become one of the most important causes of calf diarrhea.The aim of this study is to determine the patterns of antimicrobial resistance of E.coli isolates from six cattle farms and to identify pro...Escherichia coli has become one of the most important causes of calf diarrhea.The aim of this study is to determine the patterns of antimicrobial resistance of E.coli isolates from six cattle farms and to identify prominent resistance genes and virulence genes among the strains isolated from the diarrhea of calves.Antimicrobial susceptibility tests were performed using the disk diffusion method,and PCR was used to detect resistance and virulence genes.The prevalence of multidrug resistant(MDR)E.coli was 77.8%in dairy cattle and 63.6%in beef cattle.There were high resistance rates to penicillin(100%,100%)and ampicillin(96.3%,86.4%)in E.coli from dairy cattle and beef cattle.Interestingly,resistance rate to antimicrobials and distribution of resistance genes in£coli isolated from dairy cattle were higher than those in beef cattle.Further analysis showed that the most prevalent resistance genes were blojm and oodAl in dairy cattle and beef cattle,respectively.Moreover,seven diarrheagenic virulence genes(irp2,fyuA,Stx1,eoeA,F41,K99 and STa)were present in the isolates from dairy cattle,with a prevalence ranging from 3.7%to 22.22%.Six diarrheagenic virulence genes(irp2,fyuA,Stx1,eoeA,hylA and F41)were identified in the isolates from beef cattle,with a prevalence ranging from 2.27%to 63.64%.Our results provide important evidence for better exploring their interaction mechanism.Further studies are also needed to understand the origin and transmission route of£coli in cattle to reduce its prevalence.展开更多
Tryptophan(Trp)carries a unique heteroaromatic indole side chain and plays a critical role in peptide or protein modification.Herein,we have reported a metal-free photoinduced N-H alkylation strategy using N-aryl glyc...Tryptophan(Trp)carries a unique heteroaromatic indole side chain and plays a critical role in peptide or protein modification.Herein,we have reported a metal-free photoinduced N-H alkylation strategy using N-aryl glycines for specific modification of tryptophan-containing peptides.The robustness of our approach is demonstrated by its wide substrate scope,excellent isolated yields,as well as almost unobservable side effects.Using this highly efficiently metal-free condition,alkylated Trp-containing peptides can be smoothly assembled.This study provides a reliable and practical tool for the chemo-selective modification of various tryptophan containing oligopeptides.展开更多
Uncertainty in distributed renewable generation threatens the security of power distribution systems.The concept of dispatchable region is developed to assess the ability of power systems to accommodate renewable gene...Uncertainty in distributed renewable generation threatens the security of power distribution systems.The concept of dispatchable region is developed to assess the ability of power systems to accommodate renewable generation at a given operating point.Although DC and linearized AC power flow equations are typically used to model dispatchable regions for transmission systems,these equations are rarely suitable for distribution networks.To achieve a suitable trade-off between accuracy and efficiency,this paper proposes a dispatchable region formulation for distribution networks using tight convex relaxation.Secondorder cone relaxation is adopted to reformulate AC power flow equations,which are then approximated by a polyhedron to improve tractability.Further,an efficient adaptive constraint generation algorithm is employed to construct the proposed dispatchable region.Case studies on distribution systems of various scales validate the computational efficiency and accuracy of the proposed method.展开更多
Caries is considered to be the most prevalent non-communicable disease in humans, mainly deriving from acidogenic bacterial biofilm and resulting in the demineralization and decomposition of hard dental tissue. Herein...Caries is considered to be the most prevalent non-communicable disease in humans, mainly deriving from acidogenic bacterial biofilm and resulting in the demineralization and decomposition of hard dental tissue. Herein, a composite responsive foam brace loaded with magnesium organic framework (MPC) is designed for caries prevention and tooth remineralization. MPC can intelligently release organic antibacterial molecules (gallic acid) and mineralized ions (Mg2+, Ca2+ and PO43 ) under acidic conditions (pH < 5.5) of biofilm infection, regulating pH and killing bacteria. Additionally, due to the excellent photothermal conversion efficiency, MPC can further enhance the destruction of bacterial biofilm by inhibiting virulence genes and destroying bacterial adhesion under near-infrared light irradiation (808 nm). More importantly, MPC can not only reverse the cariogenic environment at both pH and microbial levels, but also promote self-healing of demineralized teeth in terms of both the micro-structure and mechanical properties.展开更多
Euphorbia factor L2, a lathyrane diterpenoid isolated from caper euphorbia seed(the seeds of Euphorbia lathyris L.), has been traditionally applied to treat cancer. This article focuses on the cytotoxic activity of Eu...Euphorbia factor L2, a lathyrane diterpenoid isolated from caper euphorbia seed(the seeds of Euphorbia lathyris L.), has been traditionally applied to treat cancer. This article focuses on the cytotoxic activity of Euphorbia factor L2 against lung carcinoma A549 cells and the mechanism by which apoptosis is induced. We analyzed the cytotoxicity and related mechanism of Euphorbia factor L2 with an MTT assay, an annexin V-FITC/PI test, a colorimetric assay, and immunoblotting. Euphorbia factor L2 showed potent cytotoxicity to A549 cells. Euphorbia factor L2 led to an increase in reactive oxygen species(ROS) generation,a loss of mitochondrial electrochemical potential, release of cytochrome c, activation of caspase-9 and caspase-3, and cleavage of poly(ADP-ribose) polymerase, suggesting that Euphorbia factor L2 induced apoptosis through a mitochondrial pathway. The cytotoxic activity of Euphorbia factor L2 in A549 cells and the related mechanisms of apoptotic induction provide support for the further investigation of caper euphorbia seeds.展开更多
The past decade has witnessed a rapid surge of interest in the research and development of non-precious metal-based electrocatalysts for the oxygen reduction reaction （ORR）. Until now, the best catalysts in acidic e...The past decade has witnessed a rapid surge of interest in the research and development of non-precious metal-based electrocatalysts for the oxygen reduction reaction （ORR）. Until now, the best catalysts in acidic electrolytes have exclusively been Fe-N-C-type materials from high-temperature pyrolysis. Despite the ORR activities of metal phthalocyanine or porphyrin macrocydes having long been known, their durability remains poor. In this work, we use these macrocycles as a basis to develop a novel organic-carbon hybrid material from in-situ polymerization of iron phthalocyanine on conductive multiwalled carbon nanotube scaffolds using a low-temperature microwave heating method. At an optimal polymer- to-carbon ratio, the hybrid electrocatalyst exhibits excellent ORR activity with a positive half-wave potential （0.80 V）, large mass activity （up to 18.0 A/g at 0.80 V）, and a low peroxide yield （〈3%）. In addition, strong electronic coupling between the polymer and carbon nanotubes is believed to suppress demetallization of the macrocycles, significantly improving cycling stability in acids. Our study represents a rare example of non-precious metal-based electrocatalysts prepared without high-temperature pyrolysis, while having ORR activity in acidic media with potential for practical applications.展开更多
Exosomes play critical roles in regulating various physiological and pathological processes,including immune stimulation,immune suppression,cardiovascular diseases,and cancers.Recent studies show that exosomes that tr...Exosomes play critical roles in regulating various physiological and pathological processes,including immune stimulation,immune suppression,cardiovascular diseases,and cancers.Recent studies show that exosomes that transport specific microRNAs(miRNAs)are involved in tumor development.However,the molecular mechanism by which tumor invasion and migration are regulated by exosomes from non-small cell lung cancer(NSCLC)is not well understood.Here,we show that exosomes shuttling low levels of miR-34c-3p are involved in NSCLC progression.Our results showed that exosomes derived from NSCLC cells carrying low levels of miR-34c-3p could be transported into the cytoplasm of NSCLC cells and accelerate NSCLC invasion and migration by upregulating integrinα2β1.A luciferase assay revealed that integrinα2β1 was the direct target of miR-34c-3p,and overexpression of integrinα2β1 could promote the invasion and migration of NSCLC cells.The analysis of exosomes derived from clinical serum samples indicated that the expression of miR-34c-3p was significantly downregulated in exosomes from NSCLC patients compared with that of normal controls.A549-derived exosomes promoted NSCLC cells lung metastases in vivo.Exosomes shuttling low levels of miR-34c-3p were associated with the progression of NSCLC in vitro and in vivo.Our data demonstrate that exosomes shuttling low levels of miR-34c-3p can accelerate the invasion and migration of NSCLC by upregulating integrinα2β1.MiR-34c-3p can be a diagnostic and prognostic marker for NSCLC.High expression of integrinα2β1 is positively related to the migration and metastasis of NSCLC cells.展开更多
Integrated electrical and heating systems(IEHSs)are promising for increasing the flexibility of power systems by exploiting the heat energy storage of pipelines.With the recent development of advanced communication te...Integrated electrical and heating systems(IEHSs)are promising for increasing the flexibility of power systems by exploiting the heat energy storage of pipelines.With the recent development of advanced communication technology,distributed optimization is employed in the coordination of IEHSs to meet the practical requirement of information privacy between different system operators.Existing studies on distributed optimization algorithms for IEHSs have seldom addressed packet loss during the process of information exchange.In this paper,a distributed paradigm is proposed for coordinating the operation of an IEHS considering communication packet loss.The relaxed alternating direction method of multipliers(R-ADMM)is derived by applying Peaceman-Rachford splitting to the Lagrangian dual of the primal problem.The proposed method is tested using several test systems in a lossy communication and transmission environment.Simulation results indicate the effectiveness and robustness of the proposed R-ADMM algorithm.展开更多
Medulloblastoma(MB)is a common yet highly heterogeneous childhood malignant brain tumor,however,clinically effective molecular targeted therapy is lacking.Modulation of hedgehog(HH)signaling by epigenetically targetin...Medulloblastoma(MB)is a common yet highly heterogeneous childhood malignant brain tumor,however,clinically effective molecular targeted therapy is lacking.Modulation of hedgehog(HH)signaling by epigenetically targeting the transcriptional factors GLI through bromodomain-containing protein 4(BRD4)has recently spurred new interest as potential treatment of HH-driven MB.Through screening of current clinical BRD4 inhibitors for their inhibitory potency against glioma-associated oncogene homolog(GLI)protein,the BRD4 inhibitor 2 was selected as the lead for further structural optimization,which led to the identification of compounds 25 and 35 as the high potency HH inhibitors.Mechanism profiling showed that both compounds suppressed HH signaling by interacting with the transcriptional factor GLI,and were equally potent against the clinical resistant mutants and the wild type of smoothened(SMO)receptor with IC50 values around 1 nmol/L.In the resistant MB allograft mice,compound 25 was well tolerated and markedly suppressed tumor growth at both 5 mg/kg(TGI=83.3%)and 10 mg/kg(TGI=87.6%)doses.Although further modification is needed to improve the pharmacokinetic(PK)parameters,compound 25 represents an efficacious lead compound of GLI inhibitors,possessing optimal safety and tolerance to fight against HH-driven MB.展开更多
The role of point-of-care(POC)diagnostics is important in public health.With the support of smartphones,POC diagnostic technologies can be greatly improved.This opportunity has arisen from not only the large number an...The role of point-of-care(POC)diagnostics is important in public health.With the support of smartphones,POC diagnostic technologies can be greatly improved.This opportunity has arisen from not only the large number and fast spread of cell-phones across the world but also their improved imaging/diagnostic functions.As a tool,the smartphone is regarded as part of a compact,portable,and low-cost system for real-time POC,even in areas with few resources.By combining near-infrared(NIR)imaging,measurement,and spectroscopy techniques,pathogens can be detected with high sensitivity.The whole process is rapid,accurate,and low-cost,and will set the future trend for POC diagnostics.In this review,the development of smartphone-based NIR fluorescent imaging technology was described,and the quality and potential of POC applications were discussed.展开更多
基金Supported by the National Innovation Planning Project for University Students (202210599001).
文摘[Objectives]To explore the hypoglycemic effect of Radix Et Rhizoma Salviae Miltiorrhizae,Guixi green tea and their compatibility on mice,so as to provide more options for the adjuvant treatment of diabetes and improve the comprehensive utilization value of Guixi green tea.[Methods]After being fed adaptively for 7 d,60 SPF-grade male mice were intraperitoneally injected with alloxouracil(180 mg/kg)to induce hyperglycemia model,from which 35 mice with a successful model were selected.They were randomly divided into 5 groups(Danshen group,green tea group,compatible group,positive control group and blank control group),with 7 animals in each group.The mice in all groups were administered according to the dose of 200 mg/kg once a day for 15 d.After the last administration,their body weight was measured on the 15 th day after fasting for 12 h,and their fasting blood glucose was measured by tail clipping.[Results]After modeling,the mice in each group showed typical hyperglycemia symptoms,namely obvious polydipsia,polyphagia,polyuria and weight loss.Compared with the blank control group,Danshen group and green tea group had obvious hypoglycemic effect(P<0.05),and compatible group had significant hypoglycemic effect(P<0.01).Compared with the blank control group,the weight loss of diabetic mice could also be inhibited in green tea group and compatible group(P<0.05).[Conclusions]Danshen,Guixi green tea and their compatibility had the effect of lowering blood sugar,among which the compatible group had the most obvious effect.
基金supported by the National Key R&D Program of China (Grant Nos.2020YFA0607501 and 2019YFA0607202 to WX)the Natural Science Foundation of Jiangsu Province (Grant No.BK20200802 to CH)the Key Laboratory of Meteorology and Ecological Environment of Hebei Province (Grant No.Z201901H to WX)。
文摘Developed regions of the world represent a major atmospheric methane(CH_4) source,but these regional emissions remain poorly constrained.The Yangtze River Delta(YRD) region of China is densely populated(about 16% of China's total population) and consists of large anthropogenic and natural CH_4 sources.Here,atmospheric CH_4 concentrations measured at a 70-m tall tower in the YRD are combined with a scale factor Bayesian inverse(SFBI) modeling approach to constrain seasonal variations in CH_4 emissions.Results indicate that in 2018 agricultural soils(AGS,rice production) were the main driver of seasonal variability in atmospheric CH_4 concentration.There was an underestimation of emissions from AGS in the a priori inventories(EDGAR—Emissions Database for Global Atmospheric Research v432 or v50),especially during the growing seasons.Posteriori CH_4 emissions from AGS accounted for 39%(4.58 Tg,EDGAR v432) to 47%(5.21 Tg,EDGAR v50) of the total CH_4 emissions.The posteriori natural emissions(including wetlands and water bodies) were1.21 Tg and 1.06 Tg,accounting for 10.1%(EDGAR v432) and 9.5%(EDGAR v50) of total emissions in the YRD in2018.Results show that the dominant factor for seasonal variations in atmospheric concentration in the YRD was AGS,followed by natural sources.In summer,AGS contributed 42%(EDGAR v432) to 64%(EDGAR v50) of the CH_4 concentration enhancement while natural sources only contributed about 10%(EDGAR v50) to 15%(EDGAR v432).In addition,the newer version of the EDGAR product(EDGAR v50) provided more reasonable seasonal distribution of CH_4 emissions from rice cultivation than the old version(EDGAR v432).
基金This study was supported by the National Science and Technology Ministry(2014BAD13B03-1)the project supported by the Heilongjiang Province Farms General Administration of China(HNK135-04-03)This work was supported by a grant from the Heilongjiang Bayi Agricultural University Support Program for San Heng San Zong(TDJH202002).
文摘Escherichia coli has become one of the most important causes of calf diarrhea.The aim of this study is to determine the patterns of antimicrobial resistance of E.coli isolates from six cattle farms and to identify prominent resistance genes and virulence genes among the strains isolated from the diarrhea of calves.Antimicrobial susceptibility tests were performed using the disk diffusion method,and PCR was used to detect resistance and virulence genes.The prevalence of multidrug resistant(MDR)E.coli was 77.8%in dairy cattle and 63.6%in beef cattle.There were high resistance rates to penicillin(100%,100%)and ampicillin(96.3%,86.4%)in E.coli from dairy cattle and beef cattle.Interestingly,resistance rate to antimicrobials and distribution of resistance genes in£coli isolated from dairy cattle were higher than those in beef cattle.Further analysis showed that the most prevalent resistance genes were blojm and oodAl in dairy cattle and beef cattle,respectively.Moreover,seven diarrheagenic virulence genes(irp2,fyuA,Stx1,eoeA,F41,K99 and STa)were present in the isolates from dairy cattle,with a prevalence ranging from 3.7%to 22.22%.Six diarrheagenic virulence genes(irp2,fyuA,Stx1,eoeA,hylA and F41)were identified in the isolates from beef cattle,with a prevalence ranging from 2.27%to 63.64%.Our results provide important evidence for better exploring their interaction mechanism.Further studies are also needed to understand the origin and transmission route of£coli in cattle to reduce its prevalence.
基金the financial support from the National Natural Science Foundation of China(No.22107062)the National Natural Science Foundation of Shanghai(No.21ZR1422600)。
文摘Tryptophan(Trp)carries a unique heteroaromatic indole side chain and plays a critical role in peptide or protein modification.Herein,we have reported a metal-free photoinduced N-H alkylation strategy using N-aryl glycines for specific modification of tryptophan-containing peptides.The robustness of our approach is demonstrated by its wide substrate scope,excellent isolated yields,as well as almost unobservable side effects.Using this highly efficiently metal-free condition,alkylated Trp-containing peptides can be smoothly assembled.This study provides a reliable and practical tool for the chemo-selective modification of various tryptophan containing oligopeptides.
基金the National Natural Science Foundation of China(Grant No.52177086)the Fundamental Research Funds for the Central Universities(Grant No.2023ZYGXZR063)。
文摘Uncertainty in distributed renewable generation threatens the security of power distribution systems.The concept of dispatchable region is developed to assess the ability of power systems to accommodate renewable generation at a given operating point.Although DC and linearized AC power flow equations are typically used to model dispatchable regions for transmission systems,these equations are rarely suitable for distribution networks.To achieve a suitable trade-off between accuracy and efficiency,this paper proposes a dispatchable region formulation for distribution networks using tight convex relaxation.Secondorder cone relaxation is adopted to reformulate AC power flow equations,which are then approximated by a polyhedron to improve tractability.Further,an efficient adaptive constraint generation algorithm is employed to construct the proposed dispatchable region.Case studies on distribution systems of various scales validate the computational efficiency and accuracy of the proposed method.
基金the National Natural Science Foundation of China(No.31860263 to Xiaolei WangNo.82160194 and No.81960492 to Lan Liao)+3 种基金Key Youth Project of Jiangxi Province(20202ACB216002 to Xiaolei Wang)Key Research and Development Program of Jiangxi Province(20212BBG73004 to Xiaolei Wang20212BBG73022 to Lan Liao)Natural Science Foundation of Jiangxi Province(No.20181ACB20022 to Lan Liao).
文摘Caries is considered to be the most prevalent non-communicable disease in humans, mainly deriving from acidogenic bacterial biofilm and resulting in the demineralization and decomposition of hard dental tissue. Herein, a composite responsive foam brace loaded with magnesium organic framework (MPC) is designed for caries prevention and tooth remineralization. MPC can intelligently release organic antibacterial molecules (gallic acid) and mineralized ions (Mg2+, Ca2+ and PO43 ) under acidic conditions (pH < 5.5) of biofilm infection, regulating pH and killing bacteria. Additionally, due to the excellent photothermal conversion efficiency, MPC can further enhance the destruction of bacterial biofilm by inhibiting virulence genes and destroying bacterial adhesion under near-infrared light irradiation (808 nm). More importantly, MPC can not only reverse the cariogenic environment at both pH and microbial levels, but also promote self-healing of demineralized teeth in terms of both the micro-structure and mechanical properties.
基金supported by National Natural Science Foundation of China (No. 81473320)Fund from Guangdong Science and Technology Department & Guangdong Academy of Traditional Chinese Medicine (2016A020226024)+1 种基金Fund of Guangdong Education Department (2015KTSCX112)the Science Fund of the Education Bureau of Guangzhou City (1201410039 and 2012C208)
文摘Euphorbia factor L2, a lathyrane diterpenoid isolated from caper euphorbia seed(the seeds of Euphorbia lathyris L.), has been traditionally applied to treat cancer. This article focuses on the cytotoxic activity of Euphorbia factor L2 against lung carcinoma A549 cells and the mechanism by which apoptosis is induced. We analyzed the cytotoxicity and related mechanism of Euphorbia factor L2 with an MTT assay, an annexin V-FITC/PI test, a colorimetric assay, and immunoblotting. Euphorbia factor L2 showed potent cytotoxicity to A549 cells. Euphorbia factor L2 led to an increase in reactive oxygen species(ROS) generation,a loss of mitochondrial electrochemical potential, release of cytochrome c, activation of caspase-9 and caspase-3, and cleavage of poly(ADP-ribose) polymerase, suggesting that Euphorbia factor L2 induced apoptosis through a mitochondrial pathway. The cytotoxic activity of Euphorbia factor L2 in A549 cells and the related mechanisms of apoptotic induction provide support for the further investigation of caper euphorbia seeds.
基金Acknowledgements We acknowledge supports from the National Natural Science Foundation of China （Nos. 51472173, 51522208 and 21472135）, the Natural Science Foundation of Jiangsu Province （Nos. BK20140302 and SBK2015010320）, the Priority Academic Program Development of Jiangsu Higher Education Institutions and Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘The past decade has witnessed a rapid surge of interest in the research and development of non-precious metal-based electrocatalysts for the oxygen reduction reaction （ORR）. Until now, the best catalysts in acidic electrolytes have exclusively been Fe-N-C-type materials from high-temperature pyrolysis. Despite the ORR activities of metal phthalocyanine or porphyrin macrocydes having long been known, their durability remains poor. In this work, we use these macrocycles as a basis to develop a novel organic-carbon hybrid material from in-situ polymerization of iron phthalocyanine on conductive multiwalled carbon nanotube scaffolds using a low-temperature microwave heating method. At an optimal polymer- to-carbon ratio, the hybrid electrocatalyst exhibits excellent ORR activity with a positive half-wave potential （0.80 V）, large mass activity （up to 18.0 A/g at 0.80 V）, and a low peroxide yield （〈3%）. In addition, strong electronic coupling between the polymer and carbon nanotubes is believed to suppress demetallization of the macrocycles, significantly improving cycling stability in acids. Our study represents a rare example of non-precious metal-based electrocatalysts prepared without high-temperature pyrolysis, while having ORR activity in acidic media with potential for practical applications.
基金supported by the National Natural Science Foundation of China(81773888,U1903126,81902152,81473320)the Fund of Guangdong Science and Technology Department(2016A020226024)+1 种基金the Fund of Guangzhou Science and Technology Program(201707010048)the Fund of Construction of High Level Universities in Guangzhou Medical University(Nanshan Scholars Program and Academic Backbone Program).
文摘Exosomes play critical roles in regulating various physiological and pathological processes,including immune stimulation,immune suppression,cardiovascular diseases,and cancers.Recent studies show that exosomes that transport specific microRNAs(miRNAs)are involved in tumor development.However,the molecular mechanism by which tumor invasion and migration are regulated by exosomes from non-small cell lung cancer(NSCLC)is not well understood.Here,we show that exosomes shuttling low levels of miR-34c-3p are involved in NSCLC progression.Our results showed that exosomes derived from NSCLC cells carrying low levels of miR-34c-3p could be transported into the cytoplasm of NSCLC cells and accelerate NSCLC invasion and migration by upregulating integrinα2β1.A luciferase assay revealed that integrinα2β1 was the direct target of miR-34c-3p,and overexpression of integrinα2β1 could promote the invasion and migration of NSCLC cells.The analysis of exosomes derived from clinical serum samples indicated that the expression of miR-34c-3p was significantly downregulated in exosomes from NSCLC patients compared with that of normal controls.A549-derived exosomes promoted NSCLC cells lung metastases in vivo.Exosomes shuttling low levels of miR-34c-3p were associated with the progression of NSCLC in vitro and in vivo.Our data demonstrate that exosomes shuttling low levels of miR-34c-3p can accelerate the invasion and migration of NSCLC by upregulating integrinα2β1.MiR-34c-3p can be a diagnostic and prognostic marker for NSCLC.High expression of integrinα2β1 is positively related to the migration and metastasis of NSCLC cells.
基金supported in part by the Key-Area Research and Development Program of Guangdong Province(No.2020B010166004)the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515011408)+1 种基金the Talent Recruitment Project of Guangdong(No.2017GC010467)the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University(No.LAPS19011)
文摘Integrated electrical and heating systems(IEHSs)are promising for increasing the flexibility of power systems by exploiting the heat energy storage of pipelines.With the recent development of advanced communication technology,distributed optimization is employed in the coordination of IEHSs to meet the practical requirement of information privacy between different system operators.Existing studies on distributed optimization algorithms for IEHSs have seldom addressed packet loss during the process of information exchange.In this paper,a distributed paradigm is proposed for coordinating the operation of an IEHS considering communication packet loss.The relaxed alternating direction method of multipliers(R-ADMM)is derived by applying Peaceman-Rachford splitting to the Lagrangian dual of the primal problem.The proposed method is tested using several test systems in a lossy communication and transmission environment.Simulation results indicate the effectiveness and robustness of the proposed R-ADMM algorithm.
基金supported by grants from National Natural Science Foundation(Grants Nos.81773565,81703327,81430080,81573452,and 81773767)Supporting grants from the Key Program of the Frontier Science(Grant No.160621,China)of the Chinese Academy of Sciences+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA12020374,China)support from the State Key Laboratory of Esophageal Cancer Prevention and Treatment,Ministry of Education of China,Zhengzhou University(Grant No.K2020-0012,China)
文摘Medulloblastoma(MB)is a common yet highly heterogeneous childhood malignant brain tumor,however,clinically effective molecular targeted therapy is lacking.Modulation of hedgehog(HH)signaling by epigenetically targeting the transcriptional factors GLI through bromodomain-containing protein 4(BRD4)has recently spurred new interest as potential treatment of HH-driven MB.Through screening of current clinical BRD4 inhibitors for their inhibitory potency against glioma-associated oncogene homolog(GLI)protein,the BRD4 inhibitor 2 was selected as the lead for further structural optimization,which led to the identification of compounds 25 and 35 as the high potency HH inhibitors.Mechanism profiling showed that both compounds suppressed HH signaling by interacting with the transcriptional factor GLI,and were equally potent against the clinical resistant mutants and the wild type of smoothened(SMO)receptor with IC50 values around 1 nmol/L.In the resistant MB allograft mice,compound 25 was well tolerated and markedly suppressed tumor growth at both 5 mg/kg(TGI=83.3%)and 10 mg/kg(TGI=87.6%)doses.Although further modification is needed to improve the pharmacokinetic(PK)parameters,compound 25 represents an efficacious lead compound of GLI inhibitors,possessing optimal safety and tolerance to fight against HH-driven MB.
基金supported by the National Natural Science Foundation of China(No.81773352)the China Scholarship Council(No.201703170071)。
文摘The role of point-of-care(POC)diagnostics is important in public health.With the support of smartphones,POC diagnostic technologies can be greatly improved.This opportunity has arisen from not only the large number and fast spread of cell-phones across the world but also their improved imaging/diagnostic functions.As a tool,the smartphone is regarded as part of a compact,portable,and low-cost system for real-time POC,even in areas with few resources.By combining near-infrared(NIR)imaging,measurement,and spectroscopy techniques,pathogens can be detected with high sensitivity.The whole process is rapid,accurate,and low-cost,and will set the future trend for POC diagnostics.In this review,the development of smartphone-based NIR fluorescent imaging technology was described,and the quality and potential of POC applications were discussed.
