OBJECTIVE Gastric cancer is one of the most common malignant tumors,and the incidence rate is the highest in all kinds of tumors in China.However,it remains unclear that how signifi.cantly gastric cells are dependent ...OBJECTIVE Gastric cancer is one of the most common malignant tumors,and the incidence rate is the highest in all kinds of tumors in China.However,it remains unclear that how signifi.cantly gastric cells are dependent on glycolysis,and which type of gastric cells are sensitive to glycolysis inhibition.In this study,several kind of gastric cancer cell lines were used as the research object,and the metabolic characteristics of different cell lines were systematically analyzed to provide theoretical support for the accurate treatment of gastric cancer.METHODS We examined the energy metabolism of four gastric cancer cell lines(MGC-803,SGC-7901,HGC-27 and BGC-823) by using glycolysis inhibitor,2-deoxy-D-glucose(2-DG) and inhibitor of oxidative phosphorylation,oligomycin.Oxygen consumption rates(OCR) and L-lactate were also measured with an XF96 Analyzer(Seahorse Biosciences) to deter.mine the significance of metabolism of oxidative phosphorylation and aerobic glycolysisin gastric cells.In addition,western blot was used to detect the contribution of AMP-activated protein kinase(AMPK),and anti-apoptotic proteins(Bcl-2 and survivin) to clarify the mechanism of death or survival of gastric cancer cells treated by 2-DG or oligomycin.RESULTS In this study,it was shown that the growth of gastric cell lines were suppressed by 2-DG.However,the sensitivity to 2-DG was quite different among cell lines:IC 50 of 2-DG was from 3.28 mmol·L^(-1)(MGC-803) to 15.57 mmol·L^(-1)(BGC-823).MGC-803 was relatively sensitive to 2-DG(IC 50:3.28 mmol·L^(-1)),consumed more glucose and produced more lactate(waste product of glycolysis) than the three other cell lines.Consequently,MGC-803 could be more dependent on glycolysis than other cell lines,which was further confirmed by the fact that glucose(+) FCS(-) medium showed more growth and survival than glucose(-) FCS(+) medium.Alternatively,BGC-823,most resistant to 2-DG(IC50:15.57 mmol · L-1),was most sensitive to oligomycin,and showed more growth and survival in glucose(-) FCS(+) medium than in glucose(+) FCS(-) medium.Thus,we had reasons to think BGC-823 cells depended on oxidative phosphorylation for energy production.In BGC-823,AMPK,which is activated when ATP becomes limiting,was rapidly phosphorylated by 2-DG,and expression of Bcl-2 was augmented,which might result in resistance to 2-DG.Interestingly,AMPK phosphorylation and augmentation of Bcl-2 expression by 2-DG were not observed in MGC-803,which is 2-DG sensitive.CONCLUSION There is a large metabolic difference between gastric cancer cell lines,which will facilitate the future gastric cancer therapy by targeting metabolic pathways.展开更多
Recently,humans have been facing serious water pollution problems that aggravate water resources shortages.By 2025,two-thirds of the world's population is likely to live in countries with moderate or severe water ...Recently,humans have been facing serious water pollution problems that aggravate water resources shortages.By 2025,two-thirds of the world's population is likely to live in countries with moderate or severe water shortages(Azizullah et al.,2011).Rivers,lakes,and reservoirs are important sources of water.Globally,there are approximately 8.5 million rivers(Linke et al.,2019),21.15 million natural lakes,and 1.427 million large reservoirs(Messager et al.,2016).Many of them have been contaminated due to urbanization,industrialization,and agricultural activities.In particular,all rivers,lakes,and reservoirs have their own slow-gathering areas(SGAs)where the input contaminants are easily stopped and deposited due to their non-open morphologies and low flow speeds.展开更多
OBJECTIVE To probe into the anti-esophagus cancer activity and mechanisms of DN3,a novel natural diterpenoid derivative.METHODS The anti-tumor activity in vitro of DN3 was evaluated by MTT,and by using human esophagea...OBJECTIVE To probe into the anti-esophagus cancer activity and mechanisms of DN3,a novel natural diterpenoid derivative.METHODS The anti-tumor activity in vitro of DN3 was evaluated by MTT,and by using human esophageal carcinoma cells xenografted into athymic mice model in vivo.The specific mechanisms of DN3,as a dual inhibitor of glycolysis and oxidative phos.phorylation(OXPHOS) were explored through cell and molecular biology techniques.For instance,the manner of cancer cell death induced by DN3 was characterized by hoechst33342,FITC-Annexin V/PI staining and flow cytometric analysis,then these changes of glucose consumption,glucose uptake and lactate production in glycolysis,as well as oxygen consumption rate(OCR) and ATP content in OXPHOS caused by DN3 were performed separately through related kits and SeahorseBioscience XF24 Extra.cellular Flux Analyzer.Furthermore,in order to obtain a clear understanding of the inhibition of DN3 to glycolysis and OXPHOS,these regulatory factors were investigated by Western blot,such as PI3K/AKT,c-Myc and p53 of glycolysis,Bax and HK2 of mitochondrial function.RESULTS DN3 inhibited the growth of esophagus cancer cell EC9706,EC109 and EC1 cells in a dose and time dependent manner,but showed no significant effects on human esophageal epithelial cells(HEECs).DN3 caused significant G2/M arrest of esophagus cancer cell lines and induced apoptosis of these cell lines,which indicated DN3 inhibited the growth of esophagus cancer cell through blocking cell cycle and inducing apoptosis in a dose and time-dependent manner.Importantly,8 μM DN3 decreased the extracellular acidification rate(ECAR) by 45% in EC109,which indicated glycolysis was inhibited by DN3.Mean.while,DN3 decreased the oxygen consumption rate(OCR) and the OCR linked to intracellular ATP production in EC109 cells,but that was not obvious in HEECs,so which indicated that DN3 could selec.tively block OXPHOS of cancer cells.In addition,the accumulation of reactive oxygen species(ROS)and the drop of mitochondrial membrane potential(MMP) were also observed in EC109 incubated by DN3,which suggested mitochondrial biological function was disturbed.Furthermore,the expression of PI3K/AKT,c-Myc and HK2 related to glycolysis were down-regulated by DN3,but the p53 and Bax were up-regulated in esophageal carcinoma cells.The changes of these enzymes accounted for the decreased glycolysisand OXPHOS in esophageal carcinoma cells treated by DN3.CONCLUSION The new compound DN3 has a strong anti-esophageal carcinoma activity,and it is tolerable that DN3 is seen as a dual inhibitor of glycolysis and oxidative phosphorylation.展开更多
OBJECTIVE To study the anti-tumor activity and molecular mechanism of natural diter.pene derivative JD20 in vitro.METHODS Screening the sensitive of gastric carcinoma cell lines to JD20 by cytotoxicity test for 24 h.C...OBJECTIVE To study the anti-tumor activity and molecular mechanism of natural diter.pene derivative JD20 in vitro.METHODS Screening the sensitive of gastric carcinoma cell lines to JD20 by cytotoxicity test for 24 h.Cell morphology was evaluated by using DAPI.After staining of can.cer cells with PI or annexin V-FITC/PI respectively,the cell cycle and apoptosis induced by JD20 were detectded by flow cytometry.The change in cell membrane potential was detected by JC-1 test kit.Western blot method was used to detect the apoptosis-related protein.RESULTS The novel natural kaurane diterpene derivative JD20 had a significant inhibitory effect on tumor cells and was particularly active on gastric cancer cell lines HGC-27(IC50=4.72±1.37 μmol·L-1) and MGC-803(IC50=7.36±0.86 μmol·L^(-1)).Further studies found that JD20 resulted in thecell cycle arrest in the G2/M phase,and induced a significant apoptosis in HGC-27.In addition,JD20 also caused the drop of mitochondrial membrane potential of HGC-27 within a short time(3 h).Furthermore,the Western blotting analysis showed that JD20 could induce the up-regulation of p53,Bax and Bim protein expression in gastric can.cer cells,and the releasing of cytochrome c from the mitochondria into the cytoplasm,as well as the ac.tivation of casepase-9/3.CONCLUSION The natural kaurane diterpene derivative JD20 can inhibit the proliferation of various human cancer cells by blocking the cell cycle and inducing apoptosis,and its mechanism of inducing apoptosis may be related to the mitochondria-mediated apoptosis pathway.展开更多
A new HPV-16/18 bivalent vaccine expressed by the Escherichia coli has been proven to be efficacious in adult women.A randomized,immunogenicity noninferiority study of this candidate vaccine was conducted in December ...A new HPV-16/18 bivalent vaccine expressed by the Escherichia coli has been proven to be efficacious in adult women.A randomized,immunogenicity noninferiority study of this candidate vaccine was conducted in December 2015 in China.Girls aged 9–14 years were randomized to receive 2 doses at months 0 and 6(n=301)or 3 doses at months 0,1 and 6(n=304).Girls aged 15–17 years(n=149)and women aged 18–26 years(n=225)received 3 doses.The objectives included noninferiority analysis of the IgG geometric mean concentration(GMC)ratio(95%CI,lower bound>0.5)to HPV-16 and HPV-18 at month 7 in girls compared with women.In the per-protocol set,the GMC ratio of IgG was noninferior for girls aged 9–17 years receiving 3 doses compared with women(1.76(95%CI,1.56,1.99)for HPV-16 and 1.93(95%CI,1.69,2.21)for HPV-18)and noninferior for girls aged 9–14 years receiving 2 doses compared with women(1.45(95%CI,1.25,1.62)for HPV-16 and 1.17(95%CI,1.02,1.33)for HPV-18).Noninferiority was also demonstrated for neutralizing antibodies.The immunogenicity of the HPV vaccine in girls receiving 3 or 2 doses was noninferior compared with that in young adult women.展开更多
Objective To analyze the trend of change in semen quality of Chinese healthy men over recent 25 years. Methods A total of 115 reports were collected on quality inspection of semen of healthy Chinese men between 1985-2...Objective To analyze the trend of change in semen quality of Chinese healthy men over recent 25 years. Methods A total of 115 reports were collected on quality inspection of semen of healthy Chinese men between 1985-2009 through literature search, which involved 23 126 persons from 69 counties and cities. Trend of change in semen parameters was analyzed by linear regression model and rank sum test. Results Sperm concentration and non-progressive motility (c%) declined, and the linear equation was of statistics value. Linear equations include y=2.968-0. 004x (P〈0.05) and y=3.204-0.026x (P〈0.05). As the results of K-S rank sum test showed, the difference of sperm concentration and total sperm count in the three groups, i.e., the group for 1985-1989, the group for 1990-1999 and the group for 2000-2009 was of statistics value. Conclusion The semen concentration decline over recent 25 years (P〈0.05). of healthy Chinese men appears a possible展开更多
A series of novel 4-substituted-phenoxy-benzamide derivatives bearing an aryl cycloaliphatic amine moiety were synthesized and evaluated for antiproliferative activity against SW620, HT29 and MGC803 cancer cell lines ...A series of novel 4-substituted-phenoxy-benzamide derivatives bearing an aryl cycloaliphatic amine moiety were synthesized and evaluated for antiproliferative activity against SW620, HT29 and MGC803 cancer cell lines in vitro. The pharmacological data demonstrated that the majority of target compounds exhibited moderate efficacy in HT29 and MGC803 cell lines. Compound 10 c showed promising inhibition of hedgehog(Hh) signaling pathway in an Hh-related assay. In addition, the superposition pattern of 10 c showed a good fit for a pharmacophoric model generated by Hh inhibitors and provided a basis for further structural optimization.展开更多
Visual inspection of wheat growth has been a useful tool for understanding and implementing agricultural techniques and a way to accurately predict the growth status of wheat yields for economists and policy decision ...Visual inspection of wheat growth has been a useful tool for understanding and implementing agricultural techniques and a way to accurately predict the growth status of wheat yields for economists and policy decision makers.In this paper,we present a polygonal approach for modeling the growth process of wheat ears.The grain,lemma,and palea of wheat ears are represented as editable polygonal models,which can be re-polygonized to detect collision during the growth process.We then rotate and move the colliding grain to resolve the collision problem.A linear interpolation and a spherical interpolation are developed to simulate the growth of wheat grain,performed in the process of heading and growth of wheat grain.Experimental results show that the method has a good modeling effect and can realize the modeling of wheat ears at different growth stages.展开更多
The stall is an unsteady flow phenomenon that always causes instabilities and low efficiency for pumps. This paper focuses on the unsteady flow structures and evolutions under two types of stall conditions in centrifu...The stall is an unsteady flow phenomenon that always causes instabilities and low efficiency for pumps. This paper focuses on the unsteady flow structures and evolutions under two types of stall conditions in centrifugal pump impellers. Two centrifugal pump impellers, one with 6 and another with 5 blades, are considered and a developed large-eddy simulation method is adopted. The results show that the alternative stall occurs in the impeller with 6 blades, while, the rotating stall is observed in that with 5 blades. The flow structure and the pressure fluctuation characteristics are further analyzed. For the alternative stall, the stall cells are fixed relative to the impeller, but a large vortex in the stalled passage is always swaying. The outlet vortex is generated from it, and then develops and sheds periodically. For the rotating stall, the stall cells first occur in the suction side of the blade. With the growth of the stall cells, the block area gradually increases until the inlet region is almost blocked, then moves to the pressure side with a continuous decay. When the rotating stall occurs, the amplitude of the pressure fluctuation is much larger than that under the alternative stall condition. The propagation of the stall cells has a significant effect on the pressure fluctuations in the impeller.展开更多
The regeneration capacity of cardiomyocytes(CMs)is retained in neonatal mouse hearts but is limited in adult mouse Myocardial infarction(MI)in adult hearts usually leads to the loss of large amounts of cardiac tissue,...The regeneration capacity of cardiomyocytes(CMs)is retained in neonatal mouse hearts but is limited in adult mouse Myocardial infarction(MI)in adult hearts usually leads to the loss of large amounts of cardiac tissue,and then accelerates the process of cardiac remodeling and heart failure.Therefore,it is necessary to explore the potential mechanisms of CM regeneration in the neonates and develop potential therapies aimed at promoting CM regeneration and cardiac repair in adults.Currently,studies indicate that a number of mechanisms are involved in neonatal endogenous myocardial regeneration,including cell cycle regulators,transcription factors,non-coding RNA,signaling pathways,acute inflammation,hypoxia,protein kinases,and others.Understanding the mechanisms of regeneration in neonatal CMs after MI provides theoretical support for the studies related to the promotion of heart repair after MI in adult mammals.However,several difficulties in the study of CM regeneration still need to be overcome.This article reviews the potential mechanisms of endogenous CM regeneration in neonatal mouse hearts and discusses possible therapeutic targets and future research directions.展开更多
Density functional theory computations were performed to investigate hydrogen adsorption in metaldecorated defective BN nanosheets. The binding energies of Ca and Sc on pristine BN nanosheets are much lower than the c...Density functional theory computations were performed to investigate hydrogen adsorption in metaldecorated defective BN nanosheets. The binding energies of Ca and Sc on pristine BN nanosheets are much lower than the corresponding cohesive energies of the bulk metals; however, B vacancies in BN nanosheets enhance the binding of Ca and Sc atoms dramatically and avoid the clustering of the metal atoms on the surface of BN nanosheets. Ca and Sc strongly bind to defective BN nanosheets due to charge transfer between metal atoms and BN nanosheets. So-decorated BN nanosheets with B vacancies demonstrate promising hydrogen adsorption performances with a hydrogen adsorption energy of -0.19 - -0.35 eV/H2.展开更多
基金supported by National Natural Science Foundation of China(81502952)
文摘OBJECTIVE Gastric cancer is one of the most common malignant tumors,and the incidence rate is the highest in all kinds of tumors in China.However,it remains unclear that how signifi.cantly gastric cells are dependent on glycolysis,and which type of gastric cells are sensitive to glycolysis inhibition.In this study,several kind of gastric cancer cell lines were used as the research object,and the metabolic characteristics of different cell lines were systematically analyzed to provide theoretical support for the accurate treatment of gastric cancer.METHODS We examined the energy metabolism of four gastric cancer cell lines(MGC-803,SGC-7901,HGC-27 and BGC-823) by using glycolysis inhibitor,2-deoxy-D-glucose(2-DG) and inhibitor of oxidative phosphorylation,oligomycin.Oxygen consumption rates(OCR) and L-lactate were also measured with an XF96 Analyzer(Seahorse Biosciences) to deter.mine the significance of metabolism of oxidative phosphorylation and aerobic glycolysisin gastric cells.In addition,western blot was used to detect the contribution of AMP-activated protein kinase(AMPK),and anti-apoptotic proteins(Bcl-2 and survivin) to clarify the mechanism of death or survival of gastric cancer cells treated by 2-DG or oligomycin.RESULTS In this study,it was shown that the growth of gastric cell lines were suppressed by 2-DG.However,the sensitivity to 2-DG was quite different among cell lines:IC 50 of 2-DG was from 3.28 mmol·L^(-1)(MGC-803) to 15.57 mmol·L^(-1)(BGC-823).MGC-803 was relatively sensitive to 2-DG(IC 50:3.28 mmol·L^(-1)),consumed more glucose and produced more lactate(waste product of glycolysis) than the three other cell lines.Consequently,MGC-803 could be more dependent on glycolysis than other cell lines,which was further confirmed by the fact that glucose(+) FCS(-) medium showed more growth and survival than glucose(-) FCS(+) medium.Alternatively,BGC-823,most resistant to 2-DG(IC50:15.57 mmol · L-1),was most sensitive to oligomycin,and showed more growth and survival in glucose(-) FCS(+) medium than in glucose(+) FCS(-) medium.Thus,we had reasons to think BGC-823 cells depended on oxidative phosphorylation for energy production.In BGC-823,AMPK,which is activated when ATP becomes limiting,was rapidly phosphorylated by 2-DG,and expression of Bcl-2 was augmented,which might result in resistance to 2-DG.Interestingly,AMPK phosphorylation and augmentation of Bcl-2 expression by 2-DG were not observed in MGC-803,which is 2-DG sensitive.CONCLUSION There is a large metabolic difference between gastric cancer cell lines,which will facilitate the future gastric cancer therapy by targeting metabolic pathways.
基金supported by the 100 Talents Initial Program of Chinese Academy of Sciences(Grant No.E190620201)the Science and Technology Program of Inner Mongolia Autonomous Region(Grant No.2021GG0089)the Scientific Research Project from the Chongqing Water Resources Bureau(Grant No.5000002021BF40001)。
文摘Recently,humans have been facing serious water pollution problems that aggravate water resources shortages.By 2025,two-thirds of the world's population is likely to live in countries with moderate or severe water shortages(Azizullah et al.,2011).Rivers,lakes,and reservoirs are important sources of water.Globally,there are approximately 8.5 million rivers(Linke et al.,2019),21.15 million natural lakes,and 1.427 million large reservoirs(Messager et al.,2016).Many of them have been contaminated due to urbanization,industrialization,and agricultural activities.In particular,all rivers,lakes,and reservoirs have their own slow-gathering areas(SGAs)where the input contaminants are easily stopped and deposited due to their non-open morphologies and low flow speeds.
基金supported by National Natural Science Foundation of China(81502952)
文摘OBJECTIVE To probe into the anti-esophagus cancer activity and mechanisms of DN3,a novel natural diterpenoid derivative.METHODS The anti-tumor activity in vitro of DN3 was evaluated by MTT,and by using human esophageal carcinoma cells xenografted into athymic mice model in vivo.The specific mechanisms of DN3,as a dual inhibitor of glycolysis and oxidative phos.phorylation(OXPHOS) were explored through cell and molecular biology techniques.For instance,the manner of cancer cell death induced by DN3 was characterized by hoechst33342,FITC-Annexin V/PI staining and flow cytometric analysis,then these changes of glucose consumption,glucose uptake and lactate production in glycolysis,as well as oxygen consumption rate(OCR) and ATP content in OXPHOS caused by DN3 were performed separately through related kits and SeahorseBioscience XF24 Extra.cellular Flux Analyzer.Furthermore,in order to obtain a clear understanding of the inhibition of DN3 to glycolysis and OXPHOS,these regulatory factors were investigated by Western blot,such as PI3K/AKT,c-Myc and p53 of glycolysis,Bax and HK2 of mitochondrial function.RESULTS DN3 inhibited the growth of esophagus cancer cell EC9706,EC109 and EC1 cells in a dose and time dependent manner,but showed no significant effects on human esophageal epithelial cells(HEECs).DN3 caused significant G2/M arrest of esophagus cancer cell lines and induced apoptosis of these cell lines,which indicated DN3 inhibited the growth of esophagus cancer cell through blocking cell cycle and inducing apoptosis in a dose and time-dependent manner.Importantly,8 μM DN3 decreased the extracellular acidification rate(ECAR) by 45% in EC109,which indicated glycolysis was inhibited by DN3.Mean.while,DN3 decreased the oxygen consumption rate(OCR) and the OCR linked to intracellular ATP production in EC109 cells,but that was not obvious in HEECs,so which indicated that DN3 could selec.tively block OXPHOS of cancer cells.In addition,the accumulation of reactive oxygen species(ROS)and the drop of mitochondrial membrane potential(MMP) were also observed in EC109 incubated by DN3,which suggested mitochondrial biological function was disturbed.Furthermore,the expression of PI3K/AKT,c-Myc and HK2 related to glycolysis were down-regulated by DN3,but the p53 and Bax were up-regulated in esophageal carcinoma cells.The changes of these enzymes accounted for the decreased glycolysisand OXPHOS in esophageal carcinoma cells treated by DN3.CONCLUSION The new compound DN3 has a strong anti-esophageal carcinoma activity,and it is tolerable that DN3 is seen as a dual inhibitor of glycolysis and oxidative phosphorylation.
基金supported by National Natural Science Foundation of China(81502952)
文摘OBJECTIVE To study the anti-tumor activity and molecular mechanism of natural diter.pene derivative JD20 in vitro.METHODS Screening the sensitive of gastric carcinoma cell lines to JD20 by cytotoxicity test for 24 h.Cell morphology was evaluated by using DAPI.After staining of can.cer cells with PI or annexin V-FITC/PI respectively,the cell cycle and apoptosis induced by JD20 were detectded by flow cytometry.The change in cell membrane potential was detected by JC-1 test kit.Western blot method was used to detect the apoptosis-related protein.RESULTS The novel natural kaurane diterpene derivative JD20 had a significant inhibitory effect on tumor cells and was particularly active on gastric cancer cell lines HGC-27(IC50=4.72±1.37 μmol·L-1) and MGC-803(IC50=7.36±0.86 μmol·L^(-1)).Further studies found that JD20 resulted in thecell cycle arrest in the G2/M phase,and induced a significant apoptosis in HGC-27.In addition,JD20 also caused the drop of mitochondrial membrane potential of HGC-27 within a short time(3 h).Furthermore,the Western blotting analysis showed that JD20 could induce the up-regulation of p53,Bax and Bim protein expression in gastric can.cer cells,and the releasing of cytochrome c from the mitochondria into the cytoplasm,as well as the ac.tivation of casepase-9/3.CONCLUSION The natural kaurane diterpene derivative JD20 can inhibit the proliferation of various human cancer cells by blocking the cell cycle and inducing apoptosis,and its mechanism of inducing apoptosis may be related to the mitochondria-mediated apoptosis pathway.
基金This work was supported by the National Natural Science Foundation of China(81673240,and U1705283)the Chinese National Major Scientific and Technological Special Project for“Significant New Drugs Development”(2018ZX09308010,2012ZX09101316)the Fujian Provincial Major Scientific and Technological Project(2015YZ0002)and Xiamen Innovax.
文摘A new HPV-16/18 bivalent vaccine expressed by the Escherichia coli has been proven to be efficacious in adult women.A randomized,immunogenicity noninferiority study of this candidate vaccine was conducted in December 2015 in China.Girls aged 9–14 years were randomized to receive 2 doses at months 0 and 6(n=301)or 3 doses at months 0,1 and 6(n=304).Girls aged 15–17 years(n=149)and women aged 18–26 years(n=225)received 3 doses.The objectives included noninferiority analysis of the IgG geometric mean concentration(GMC)ratio(95%CI,lower bound>0.5)to HPV-16 and HPV-18 at month 7 in girls compared with women.In the per-protocol set,the GMC ratio of IgG was noninferior for girls aged 9–17 years receiving 3 doses compared with women(1.76(95%CI,1.56,1.99)for HPV-16 and 1.93(95%CI,1.69,2.21)for HPV-18)and noninferior for girls aged 9–14 years receiving 2 doses compared with women(1.45(95%CI,1.25,1.62)for HPV-16 and 1.17(95%CI,1.02,1.33)for HPV-18).Noninferiority was also demonstrated for neutralizing antibodies.The immunogenicity of the HPV vaccine in girls receiving 3 or 2 doses was noninferior compared with that in young adult women.
基金supported by the Key Project of National Natural Science Foundation of China(No.30630056)the Program of S&T (Chongqing) Project(No.CSTC 2006AA703)
文摘Objective To analyze the trend of change in semen quality of Chinese healthy men over recent 25 years. Methods A total of 115 reports were collected on quality inspection of semen of healthy Chinese men between 1985-2009 through literature search, which involved 23 126 persons from 69 counties and cities. Trend of change in semen parameters was analyzed by linear regression model and rank sum test. Results Sperm concentration and non-progressive motility (c%) declined, and the linear equation was of statistics value. Linear equations include y=2.968-0. 004x (P〈0.05) and y=3.204-0.026x (P〈0.05). As the results of K-S rank sum test showed, the difference of sperm concentration and total sperm count in the three groups, i.e., the group for 1985-1989, the group for 1990-1999 and the group for 2000-2009 was of statistics value. Conclusion The semen concentration decline over recent 25 years (P〈0.05). of healthy Chinese men appears a possible
基金supported by Program for Innovative Research Team of the Ministry of Education of ChinaProgram for Liaoning Innovative Research Team in Universitythe Innovation and entrepreneurship training program for college students in Liaoning Province (No. 201410163009)
文摘A series of novel 4-substituted-phenoxy-benzamide derivatives bearing an aryl cycloaliphatic amine moiety were synthesized and evaluated for antiproliferative activity against SW620, HT29 and MGC803 cancer cell lines in vitro. The pharmacological data demonstrated that the majority of target compounds exhibited moderate efficacy in HT29 and MGC803 cell lines. Compound 10 c showed promising inhibition of hedgehog(Hh) signaling pathway in an Hh-related assay. In addition, the superposition pattern of 10 c showed a good fit for a pharmacophoric model generated by Hh inhibitors and provided a basis for further structural optimization.
基金the National Natural Science Foundation of China(Nos.61772474,61872324,and 61822701)the Natural Science Foundation of Henan Province of China(No.162300410262)the Key Research Projects of Henan Higher Education Institutions of China(No.18A413002)。
文摘Visual inspection of wheat growth has been a useful tool for understanding and implementing agricultural techniques and a way to accurately predict the growth status of wheat yields for economists and policy decision makers.In this paper,we present a polygonal approach for modeling the growth process of wheat ears.The grain,lemma,and palea of wheat ears are represented as editable polygonal models,which can be re-polygonized to detect collision during the growth process.We then rotate and move the colliding grain to resolve the collision problem.A linear interpolation and a spherical interpolation are developed to simulate the growth of wheat grain,performed in the process of heading and growth of wheat grain.Experimental results show that the method has a good modeling effect and can realize the modeling of wheat ears at different growth stages.
基金supported by the National Natural Science Foundation of China(81991491,82273640,and 82072323)CAMS Innovation Fund for Medical Sciences of China(2019RU022)+1 种基金Fundamental Research Funds for the Central Universities(20720220006 and 20720200105)Xiamen Innovax(provided qualified test and control vaccine)。
基金Project supported by the National Nature Science Foundation of China(Grant Nos.51709234,51779226)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ17E090005)
文摘The stall is an unsteady flow phenomenon that always causes instabilities and low efficiency for pumps. This paper focuses on the unsteady flow structures and evolutions under two types of stall conditions in centrifugal pump impellers. Two centrifugal pump impellers, one with 6 and another with 5 blades, are considered and a developed large-eddy simulation method is adopted. The results show that the alternative stall occurs in the impeller with 6 blades, while, the rotating stall is observed in that with 5 blades. The flow structure and the pressure fluctuation characteristics are further analyzed. For the alternative stall, the stall cells are fixed relative to the impeller, but a large vortex in the stalled passage is always swaying. The outlet vortex is generated from it, and then develops and sheds periodically. For the rotating stall, the stall cells first occur in the suction side of the blade. With the growth of the stall cells, the block area gradually increases until the inlet region is almost blocked, then moves to the pressure side with a continuous decay. When the rotating stall occurs, the amplitude of the pressure fluctuation is much larger than that under the alternative stall condition. The propagation of the stall cells has a significant effect on the pressure fluctuations in the impeller.
基金This work was supported by a grant from the National Natural Science Foundation of China(No.81770361).
文摘The regeneration capacity of cardiomyocytes(CMs)is retained in neonatal mouse hearts but is limited in adult mouse Myocardial infarction(MI)in adult hearts usually leads to the loss of large amounts of cardiac tissue,and then accelerates the process of cardiac remodeling and heart failure.Therefore,it is necessary to explore the potential mechanisms of CM regeneration in the neonates and develop potential therapies aimed at promoting CM regeneration and cardiac repair in adults.Currently,studies indicate that a number of mechanisms are involved in neonatal endogenous myocardial regeneration,including cell cycle regulators,transcription factors,non-coding RNA,signaling pathways,acute inflammation,hypoxia,protein kinases,and others.Understanding the mechanisms of regeneration in neonatal CMs after MI provides theoretical support for the studies related to the promotion of heart repair after MI in adult mammals.However,several difficulties in the study of CM regeneration still need to be overcome.This article reviews the potential mechanisms of endogenous CM regeneration in neonatal mouse hearts and discusses possible therapeutic targets and future research directions.
文摘Density functional theory computations were performed to investigate hydrogen adsorption in metaldecorated defective BN nanosheets. The binding energies of Ca and Sc on pristine BN nanosheets are much lower than the corresponding cohesive energies of the bulk metals; however, B vacancies in BN nanosheets enhance the binding of Ca and Sc atoms dramatically and avoid the clustering of the metal atoms on the surface of BN nanosheets. Ca and Sc strongly bind to defective BN nanosheets due to charge transfer between metal atoms and BN nanosheets. So-decorated BN nanosheets with B vacancies demonstrate promising hydrogen adsorption performances with a hydrogen adsorption energy of -0.19 - -0.35 eV/H2.