Objective To investigate the effect of simulated microgravity and carbon ion irradiation （CIR） on spermatogenic cell apoptosis and sperm DNA damage to the testis of male Swiss Webster mice, and assess the risk assoc...Objective To investigate the effect of simulated microgravity and carbon ion irradiation （CIR） on spermatogenic cell apoptosis and sperm DNA damage to the testis of male Swiss Webster mice, and assess the risk associated with space environment. Methods Sperm DNA damage indicated by DNA fragmentation index （DFI） and high DNA stainability （HDS） was measured by sperm chromatin structure assay （SCSA）. Apoptosis of spermatogenic cells was detected by annexin V-propidium iodide assay. Bax （the expression levels of p53） and proliferating cell nuclear antigen （PCNAI were measured by immunoblotting; p53 and PCNA were located by immunohistology. Results HDS, DFI, apoptosis index, and the expression levels of p53 and Bax were detected to be significantly higher in the experimental groups （P〈0.05） compared with those in the control group, however, the PCNA expression varied to a certain degree, p53- and PCNA- positive expression were detected in each group, mainly in relation to the spermatogonic cells and spermatocytes. Conclusion The findings of the present study demonstrated that simulated microgravity and CIR can induce spermatogenic cell apoptosis and sperm DNA damage. Sperm DNA damage may be one of the underlying mechanisms behind male fertility decline under space environment. These findings may provide a scientific basis for protectint~ astronauts and space traveler＇s health and safety.展开更多
Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed pr...Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed protective effect on cerebral ischemic injury. Here we investigated the effects of shikonin on carbon ion beam induced radiation brain injury in mice. Pretreatment with shikonin significantly increased the SOD and CAT activities and the ratio of GSH/GSSG in mouse brain tissues compared with irradiated group （P〈0.01）, while obviously reduced the MDA and PCO contents and the RO$ levels derived from of the brain mitochondria.展开更多
Objective To better understand the mechanism of chlorine resistance of mycobacteria and evaluate the efficiency of various disinfection processes.Methods Inactivation experiments of one strain Mycobacteria mucogenicum...Objective To better understand the mechanism of chlorine resistance of mycobacteria and evaluate the efficiency of various disinfection processes.Methods Inactivation experiments of one strain Mycobacteria mucogenicum,isolated from a drinking water distribution system in South China were conducted with various chlorine disinfectants.Inactivation efficiency and disinfectant residual,as well as the formation of organic chloramines,were measured during the experiments.Results This strain of M.mucogenicum showed high resistance to chlorine.The CT values of 99.9% inactivation by free chlorine,monochloramine and chlorine dioxide were detected as 29.6±1.46,170±6.16,and 10.9±1.55 min（mg/L） respectively,indicating that chlorine dioxide exhibited significantly higher efficiency than free chlorine and monochloramine.It was also found that M.mucogenicum reacted with chlorine disinfectants more slowly than S.aureus,but consumed more chlorine disinfectants during longer time of contact.Lipid analysis of the cell construction revealed that 95.7% of cell membrane lipid of M.mucogenicum was composed of saturated long chain fatty acids.Saturated fatty acids were regarded as more stable and more hydrophilic which enabled the cell membrane to prevent the diffusion of chlorine.Conclusion It was concluded that different compositions of cell membrane might endow M.mucogenicum with a higher chlorine resistance.展开更多
We designed two types of pre-adaption plans for this study. One was a pre-adaption training with progressive intermittent hypoxia, with a constant lower pressure oxygen tank used in the plain before arriving at the pl...We designed two types of pre-adaption plans for this study. One was a pre-adaption training with progressive intermittent hypoxia, with a constant lower pressure oxygen tank used in the plain before arriving at the plateau （PG）. The other was by progressively increasing the time of exposure to hypoxia with oxygen supplied in stages after radical plateau （RG）. By testing the blood oxygen saturation （SpO2）, heart rate （HR）, and quality of sleep after arriving at the 3800 m high plateau, results showed that the pre-acclimatization and radical groups performed better than the control group （CG）. Both strategies were equivalent in terms of effects and principles in providing more flexible choices for acclimatization.展开更多
The community is a necessary environment with the help of which people with mental disorders can be rehabilitated and can return to society.The WHO(World Health Organization)advocates that mental health services shoul...The community is a necessary environment with the help of which people with mental disorders can be rehabilitated and can return to society.The WHO(World Health Organization)advocates that mental health services should be available at the grassroots level and be integrated systematically into the primary healthcare(PHC)system[1].The WHO's Comprehensive Mental Health Action Plan 2013-2020 also sets one of the four objectives in community-based settings:the provisi on of comprehe nsive,in tegrated mental health and social care services[2].According to the WHO's Project Atlas,published in 2001,community care facilities for mental health exist in 63.4%of countries(n=183),covering 79.9%of the world's population[3].Specialists and researchers in numerous countries have recognized and affirmed the effectiveness of community-based management for mental disorders[4,5] associated with the reform[6,7].展开更多
Microtubules are involved in a variety of cellular functions such as cell division, intracellular transport, maintenance of cell polarity and flagella and ciliary motility. The heterogeneity of tubulin and microtubule...Microtubules are involved in a variety of cellular functions such as cell division, intracellular transport, maintenance of cell polarity and flagella and ciliary motility. The heterogeneity of tubulin and microtubule-associated proteins is responsible for these different microtubule functions. Many studies have confirmed that the structure and function of the different α-tubulin and β-tubulin subunits can affect the microtubule. The sperm axoneme microtubule has linear fiber filaments which are polymerized by heterodimeric a and β-tubulin, each with a molecular mass of approximately 50 kD[1].展开更多
Nitroguanidine（NQ） isa high energy and low sensitivity explosive and solid-liquid equilibrium data are significant for study on crystallization of NQ. The solubilities of NQ in water, dimethyl sulfoxide, N, N dimeth...Nitroguanidine（NQ） isa high energy and low sensitivity explosive and solid-liquid equilibrium data are significant for study on crystallization of NQ. The solubilities of NQ in water, dimethyl sulfoxide, N, N dimethylformamide, 1,4 butyrolaetone and dimethyl sulfoxide @ water, N, N dimethylformamide ＋ water were measured by dynamic laser monitoring within a temperature range from 298. 15 K to 338. 15 K. The experimental data were correlated by modified Apelblat equation, 2h equation, CNIBS/R K model, andJouyban-Acree model. The results show that the four thermodynamic models can all be used to predict solubility with high accuracy. Accrding to the Akaike＇s information criterion （AIC）, the better models for correlating the solubility of NQ are judged. Additionally, the dissolution enthalpy, entropy and Gibbs free energy were calculated by the van＇t Hoff equation.展开更多
基金supported by the Knowledge Innovation Project of the Chinese Academy of Sciences(KJCX2-YW-L08)the National Basic Research Program of China(2010CB834202)+1 种基金the National Natural Science Foundation of China(10835011)the Scientific Technology Research Projects of Gansu Province(0702NKDA045,0806RJYA020)
文摘Objective To investigate the effect of simulated microgravity and carbon ion irradiation （CIR） on spermatogenic cell apoptosis and sperm DNA damage to the testis of male Swiss Webster mice, and assess the risk associated with space environment. Methods Sperm DNA damage indicated by DNA fragmentation index （DFI） and high DNA stainability （HDS） was measured by sperm chromatin structure assay （SCSA）. Apoptosis of spermatogenic cells was detected by annexin V-propidium iodide assay. Bax （the expression levels of p53） and proliferating cell nuclear antigen （PCNAI were measured by immunoblotting; p53 and PCNA were located by immunohistology. Results HDS, DFI, apoptosis index, and the expression levels of p53 and Bax were detected to be significantly higher in the experimental groups （P〈0.05） compared with those in the control group, however, the PCNA expression varied to a certain degree, p53- and PCNA- positive expression were detected in each group, mainly in relation to the spermatogonic cells and spermatocytes. Conclusion The findings of the present study demonstrated that simulated microgravity and CIR can induce spermatogenic cell apoptosis and sperm DNA damage. Sperm DNA damage may be one of the underlying mechanisms behind male fertility decline under space environment. These findings may provide a scientific basis for protectint~ astronauts and space traveler＇s health and safety.
基金supported by Key Program of National Natural Science Foundation of China(U1432248)National Natural Science Foundation of China(11175222,11305226)
文摘Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed protective effect on cerebral ischemic injury. Here we investigated the effects of shikonin on carbon ion beam induced radiation brain injury in mice. Pretreatment with shikonin significantly increased the SOD and CAT activities and the ratio of GSH/GSSG in mouse brain tissues compared with irradiated group （P〈0.01）, while obviously reduced the MDA and PCO contents and the RO$ levels derived from of the brain mitochondria.
基金funded by the Major Science and Technology Program for Water Pollution Control and Treatment (No. 2008ZX07420‐005)National Natural Science Foundation of China (No. 50708050)
文摘Objective To better understand the mechanism of chlorine resistance of mycobacteria and evaluate the efficiency of various disinfection processes.Methods Inactivation experiments of one strain Mycobacteria mucogenicum,isolated from a drinking water distribution system in South China were conducted with various chlorine disinfectants.Inactivation efficiency and disinfectant residual,as well as the formation of organic chloramines,were measured during the experiments.Results This strain of M.mucogenicum showed high resistance to chlorine.The CT values of 99.9% inactivation by free chlorine,monochloramine and chlorine dioxide were detected as 29.6±1.46,170±6.16,and 10.9±1.55 min（mg/L） respectively,indicating that chlorine dioxide exhibited significantly higher efficiency than free chlorine and monochloramine.It was also found that M.mucogenicum reacted with chlorine disinfectants more slowly than S.aureus,but consumed more chlorine disinfectants during longer time of contact.Lipid analysis of the cell construction revealed that 95.7% of cell membrane lipid of M.mucogenicum was composed of saturated long chain fatty acids.Saturated fatty acids were regarded as more stable and more hydrophilic which enabled the cell membrane to prevent the diffusion of chlorine.Conclusion It was concluded that different compositions of cell membrane might endow M.mucogenicum with a higher chlorine resistance.
基金supported in part by the national basic research program of China 973 program(NO.2012CB518200-G)Army major issue of comprehensive medical security research of flight crew in the plateau(N0.AKJ11J005)
文摘We designed two types of pre-adaption plans for this study. One was a pre-adaption training with progressive intermittent hypoxia, with a constant lower pressure oxygen tank used in the plain before arriving at the plateau （PG）. The other was by progressively increasing the time of exposure to hypoxia with oxygen supplied in stages after radical plateau （RG）. By testing the blood oxygen saturation （SpO2）, heart rate （HR）, and quality of sleep after arriving at the 3800 m high plateau, results showed that the pre-acclimatization and radical groups performed better than the control group （CG）. Both strategies were equivalent in terms of effects and principles in providing more flexible choices for acclimatization.
文摘The community is a necessary environment with the help of which people with mental disorders can be rehabilitated and can return to society.The WHO(World Health Organization)advocates that mental health services should be available at the grassroots level and be integrated systematically into the primary healthcare(PHC)system[1].The WHO's Comprehensive Mental Health Action Plan 2013-2020 also sets one of the four objectives in community-based settings:the provisi on of comprehe nsive,in tegrated mental health and social care services[2].According to the WHO's Project Atlas,published in 2001,community care facilities for mental health exist in 63.4%of countries(n=183),covering 79.9%of the world's population[3].Specialists and researchers in numerous countries have recognized and affirmed the effectiveness of community-based management for mental disorders[4,5] associated with the reform[6,7].
基金supported by grants from the National Basic Research Program of China(2010CB834202)The National Natural Science Foundation of China(10835011)the Scientific Technology Research Projects of Gansu Province(0702NKDA045,0806RJYA020)
文摘Microtubules are involved in a variety of cellular functions such as cell division, intracellular transport, maintenance of cell polarity and flagella and ciliary motility. The heterogeneity of tubulin and microtubule-associated proteins is responsible for these different microtubule functions. Many studies have confirmed that the structure and function of the different α-tubulin and β-tubulin subunits can affect the microtubule. The sperm axoneme microtubule has linear fiber filaments which are polymerized by heterodimeric a and β-tubulin, each with a molecular mass of approximately 50 kD[1].
文摘Nitroguanidine（NQ） isa high energy and low sensitivity explosive and solid-liquid equilibrium data are significant for study on crystallization of NQ. The solubilities of NQ in water, dimethyl sulfoxide, N, N dimethylformamide, 1,4 butyrolaetone and dimethyl sulfoxide @ water, N, N dimethylformamide ＋ water were measured by dynamic laser monitoring within a temperature range from 298. 15 K to 338. 15 K. The experimental data were correlated by modified Apelblat equation, 2h equation, CNIBS/R K model, andJouyban-Acree model. The results show that the four thermodynamic models can all be used to predict solubility with high accuracy. Accrding to the Akaike＇s information criterion （AIC）, the better models for correlating the solubility of NQ are judged. Additionally, the dissolution enthalpy, entropy and Gibbs free energy were calculated by the van＇t Hoff equation.
