BACKGROUND Human spermatogonial stem cells(SSCs)are the basis of spermatogenesis.However,little is known about the developmental regulatory mechanisms of SSC due to sample origin and species differences.AIM To investi...BACKGROUND Human spermatogonial stem cells(SSCs)are the basis of spermatogenesis.However,little is known about the developmental regulatory mechanisms of SSC due to sample origin and species differences.AIM To investigates the mechanisms involved in the proliferation of human SSC.METHODS The expression of mitogen-activated protein kinase kinase 7(MKK7)in human testis was identified using immunohistochemistry and western blotting(WB).MKK7 was knocked down using small interfering RNA,and cell proliferation and apoptosis were detected by WB,EdU,cell counting kit-8 and fluorescenceactivated cell sorting.After bioinformatic analysis,the interaction of MKK7 with c-Jun N-terminal kinases(JNKs)was verified by protein co-immunoprecipitation and WB.The phosphorylation of JNKs was inhibited by SP600125,and the phenotypic changes were detected by WB,cell counting kit-8 and fluorescenceactivated cell sorting.RESULTS MKK7 is mainly expressed in human SSCs,and MKK7 knockdown inhibits SSC proliferation and promotes their apoptosis.MKK7 mediated the phosphorylation of JNKs,and after inhibiting the phosphorylation of JNKs,the phenotypic changes of the cells were similar to those after MKK7 downregulation.The expression of MKK7 was significantly downregulated in patients with abnormal spermatogenesis,suggesting that abnormal MKK7 may be associated with spermatogenesis impairment.CONCLUSION MKK7 regulates the proliferation and apoptosis of human SSC by mediating the phosphorylation of JNKs.展开更多
UV/peroxymonosulfate(UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be pe...UV/peroxymonosulfate(UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole(SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product(DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane(TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief(5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5–1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation.展开更多
In the 1960s,sperm cryopreservation was developed as a method to preserve fertility.Currently,techniques for the cryopreservation of human spermatozoa have been widely used in assisted reproduction.However,although sp...In the 1960s,sperm cryopreservation was developed as a method to preserve fertility.Currently,techniques for the cryopreservation of human spermatozoa have been widely used in assisted reproduction.However,although sperm cryobiology has made notable achievements,the optimal method for the recovery of viable spermatozoa after cryopreservation remains elusive.Postthawing sperm quality can be affected by cryoprotectants,ice formation,storage conditions,and osmotic stress during the freezing process.This review discusses recent advances in different cryopreservation techniques,cryoprotectants,and freezing and thawing methods during cryopreservation and new indications for the use of cryopreserved spermatozoa.展开更多
A novel photocatalytic reactor was developed to remove （1,1-bis（4-chlorophenyl）-2,2,2-trichloroethane） （DDT） from water. In the reactor, a cenosphere was used to support TiO2 film made by means of sol-gel. Becau...A novel photocatalytic reactor was developed to remove （1,1-bis（4-chlorophenyl）-2,2,2-trichloroethane） （DDT） from water. In the reactor, a cenosphere was used to support TiO2 film made by means of sol-gel. Because the cenospheres were coated with TiO2, their specific gravity was slightly increased from the original 0.6-0.8 to 0.8-0.9, so that they were able to be suspended in water. With the mixed operation of a bubbler, the water in the reactor was in a well-fluidized state. The bottom of the reactor is a sand filter bed, which can be used to prevent the photocatalyst from being lost. A mathematical model of the reactor has been developed in the two primary influential factors： ultraviolet （UV） light intensity and photocatalyst concentration. With such a model, the reactor can be designed more reasonably.展开更多
基金Supported by China Postdoctoral Science Foundation,No.2019M661521and National Natural Science Foundation of China,No.82001634.
文摘BACKGROUND Human spermatogonial stem cells(SSCs)are the basis of spermatogenesis.However,little is known about the developmental regulatory mechanisms of SSC due to sample origin and species differences.AIM To investigates the mechanisms involved in the proliferation of human SSC.METHODS The expression of mitogen-activated protein kinase kinase 7(MKK7)in human testis was identified using immunohistochemistry and western blotting(WB).MKK7 was knocked down using small interfering RNA,and cell proliferation and apoptosis were detected by WB,EdU,cell counting kit-8 and fluorescenceactivated cell sorting.After bioinformatic analysis,the interaction of MKK7 with c-Jun N-terminal kinases(JNKs)was verified by protein co-immunoprecipitation and WB.The phosphorylation of JNKs was inhibited by SP600125,and the phenotypic changes were detected by WB,cell counting kit-8 and fluorescenceactivated cell sorting.RESULTS MKK7 is mainly expressed in human SSCs,and MKK7 knockdown inhibits SSC proliferation and promotes their apoptosis.MKK7 mediated the phosphorylation of JNKs,and after inhibiting the phosphorylation of JNKs,the phenotypic changes of the cells were similar to those after MKK7 downregulation.The expression of MKK7 was significantly downregulated in patients with abnormal spermatogenesis,suggesting that abnormal MKK7 may be associated with spermatogenesis impairment.CONCLUSION MKK7 regulates the proliferation and apoptosis of human SSC by mediating the phosphorylation of JNKs.
基金sponsored by the National Natural Science Foundation of China (Nos. 52070144 , 51978483 , 51808222)the National Key Research and Development Program (No. 2021YFC3201303)。
文摘UV/peroxymonosulfate(UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole(SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product(DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane(TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief(5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5–1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation.
基金supported by the National Natural Science Foundation of China(No.82001634)the China Postdoctoral Science Foundation(No.2019M661521).
文摘In the 1960s,sperm cryopreservation was developed as a method to preserve fertility.Currently,techniques for the cryopreservation of human spermatozoa have been widely used in assisted reproduction.However,although sperm cryobiology has made notable achievements,the optimal method for the recovery of viable spermatozoa after cryopreservation remains elusive.Postthawing sperm quality can be affected by cryoprotectants,ice formation,storage conditions,and osmotic stress during the freezing process.This review discusses recent advances in different cryopreservation techniques,cryoprotectants,and freezing and thawing methods during cryopreservation and new indications for the use of cryopreserved spermatozoa.
基金supported by the National Science and Technology Support Program of China (No. 2006BAJ08B06)the Major Projects on Control and Rectification of Water Body Pollution by Ministry of Environmental Protection (No. 2008ZX07421-002), China
文摘A novel photocatalytic reactor was developed to remove （1,1-bis（4-chlorophenyl）-2,2,2-trichloroethane） （DDT） from water. In the reactor, a cenosphere was used to support TiO2 film made by means of sol-gel. Because the cenospheres were coated with TiO2, their specific gravity was slightly increased from the original 0.6-0.8 to 0.8-0.9, so that they were able to be suspended in water. With the mixed operation of a bubbler, the water in the reactor was in a well-fluidized state. The bottom of the reactor is a sand filter bed, which can be used to prevent the photocatalyst from being lost. A mathematical model of the reactor has been developed in the two primary influential factors： ultraviolet （UV） light intensity and photocatalyst concentration. With such a model, the reactor can be designed more reasonably.
