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
Carbon ion radiotherapy has the advantages of better therapeutic effect and fewer side effects compared with those of X-rays in many kinds of tumors,including prostate cancer,and thus is an attractive treatment approa...Carbon ion radiotherapy has the advantages of better therapeutic effect and fewer side effects compared with those of X-rays in many kinds of tumors,including prostate cancer,and thus is an attractive treatment approach for prostate cancer.However,the biological effects and underlying mechanisms of carbon ion irradiation in prostate cancer are not yet fully understood.Therefore,this study systematically compared the effects of carbon ion irradiation with those of X-ray irradiation on DNA damage response and found that carbon ion irradiation was more effective than X-ray irradiation.Carbon ion irradiation can induce a high level of DNA double-strand break damage,reflected by the number of y-H2 A histone family member X foci,as well as by the foci lasting time and size.Moreover,carbon ion irradiation exhibited strong and long-lasting inhibitory effect on cell survival capability,induced prolonged cell cycle arrest,and increased apoptosis in PC-3 cells.As an underlying mechanism,we speculated that carbon ion irradiation-induced DNA damage evokes cell cycle arrest and apoptosis via the pRb/E2 F1/c-Myc signaling pathway to enhance the radiosensitivity of p53-deficient prostate cancer PC-3 cells.Collectively,the present study suggests that carbon ion irradiation is more efficient than X-ray irradiation and may help to understand the effects of different radiation qualities on the survival potential of p53-deficient prostate cancer cells.展开更多
Microstructure evolution and hardening effect of pure tungsten and W-1.5%ZrO_(2) alloy under carbon ion irradiation are investigated by using transmission electron microscopy and nano-indentation.Carbon ion irradiatio...Microstructure evolution and hardening effect of pure tungsten and W-1.5%ZrO_(2) alloy under carbon ion irradiation are investigated by using transmission electron microscopy and nano-indentation.Carbon ion irradiation is performed at 700℃ with irradiation damages ranging from 0.25 dpa to 2.0 dpa.The results show that the irradiation defect clusters are mainly in the form of dislocation loop.The size and density of dislocation loops increase with irradiation damages intensifying.The W-1.5%ZrO_(2) alloy has a smaller dislocation loop size than that of pure tungsten.It is proposed that the phase boundaries have the ability to absorb and annihilate defects and the addition of ZrO_(2) phase improves the sink strength for irradiation defects.It is confirmed that the W-1.5% ZrO_(2) alloy shows a smaller change in hardness than the pure tungsten after being irradiated.From the above results,we conclude that the addition of ZrO_(2) into tungsten can significantly reduce the accumulation of irradiated defects and improve the irradiation resistance behaviors of the tungsten materials.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
The objective of this work was to produce citric acid from corn starch using a newly isolated mutant of Aspergillus niger, and to analyze the relationship between changes in the physiological properties of A. niger in...The objective of this work was to produce citric acid from corn starch using a newly isolated mutant of Aspergillus niger, and to analyze the relationship between changes in the physiological properties of A. niger induced by carbon ion irradiation and citric acid accumulation. Our results showed that the physiological characteristics of conidia in A. niger were closely related to citric acid accumulation and that lower growth rate and viability of conidia may be beneficial to citric acid accumulation. Using corn starch as a raw material, a high-yielding citric acid mutant, named HW2, was obtained. In a 10-L bioreactor, HW2 can accumulate 118.9 g/L citdc acid with a residual total sugar concentration of only 14.4 g/L. This represented an 18% increase in citric acid accumulation and a 12.5% decrease in sugar utilization compared with the original strain.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
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 the National Key R&D Program of China(No.2018YFE0205100)the Key Program of the National Natural Science Foundation of China(No.U1632270)+1 种基金National Natural Science Foundation of China(No.11665003)Cancer Research Youth Science Foundation of Chinese Anti-cancer Association(No.CAYC18A06)。
文摘Carbon ion radiotherapy has the advantages of better therapeutic effect and fewer side effects compared with those of X-rays in many kinds of tumors,including prostate cancer,and thus is an attractive treatment approach for prostate cancer.However,the biological effects and underlying mechanisms of carbon ion irradiation in prostate cancer are not yet fully understood.Therefore,this study systematically compared the effects of carbon ion irradiation with those of X-ray irradiation on DNA damage response and found that carbon ion irradiation was more effective than X-ray irradiation.Carbon ion irradiation can induce a high level of DNA double-strand break damage,reflected by the number of y-H2 A histone family member X foci,as well as by the foci lasting time and size.Moreover,carbon ion irradiation exhibited strong and long-lasting inhibitory effect on cell survival capability,induced prolonged cell cycle arrest,and increased apoptosis in PC-3 cells.As an underlying mechanism,we speculated that carbon ion irradiation-induced DNA damage evokes cell cycle arrest and apoptosis via the pRb/E2 F1/c-Myc signaling pathway to enhance the radiosensitivity of p53-deficient prostate cancer PC-3 cells.Collectively,the present study suggests that carbon ion irradiation is more efficient than X-ray irradiation and may help to understand the effects of different radiation qualities on the survival potential of p53-deficient prostate cancer cells.
基金Project supported by the President's Foundation of the ChinaAcademy of Engineering Physics(Grant No.YZJJLX2018003)the National Natural Science Foundation of China(Grant Nos.U2004180 and 12105261)the Program for Changjiang Scholars and Innovative Research Team in Universities,China(Grant No.IRT1234).
文摘Microstructure evolution and hardening effect of pure tungsten and W-1.5%ZrO_(2) alloy under carbon ion irradiation are investigated by using transmission electron microscopy and nano-indentation.Carbon ion irradiation is performed at 700℃ with irradiation damages ranging from 0.25 dpa to 2.0 dpa.The results show that the irradiation defect clusters are mainly in the form of dislocation loop.The size and density of dislocation loops increase with irradiation damages intensifying.The W-1.5%ZrO_(2) alloy has a smaller dislocation loop size than that of pure tungsten.It is proposed that the phase boundaries have the ability to absorb and annihilate defects and the addition of ZrO_(2) phase improves the sink strength for irradiation defects.It is confirmed that the W-1.5% ZrO_(2) alloy shows a smaller change in hardness than the pure tungsten after being irradiated.From the above results,we conclude that the addition of ZrO_(2) into tungsten can significantly reduce the accumulation of irradiated defects and improve the irradiation resistance behaviors of the tungsten materials.
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].
基金supported by the Agriculture Science Technology Achievement Transformation Fund(No.2013GB24910680),China
文摘The objective of this work was to produce citric acid from corn starch using a newly isolated mutant of Aspergillus niger, and to analyze the relationship between changes in the physiological properties of A. niger induced by carbon ion irradiation and citric acid accumulation. Our results showed that the physiological characteristics of conidia in A. niger were closely related to citric acid accumulation and that lower growth rate and viability of conidia may be beneficial to citric acid accumulation. Using corn starch as a raw material, a high-yielding citric acid mutant, named HW2, was obtained. In a 10-L bioreactor, HW2 can accumulate 118.9 g/L citdc acid with a residual total sugar concentration of only 14.4 g/L. This represented an 18% increase in citric acid accumulation and a 12.5% decrease in sugar utilization compared with the original strain.
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.
