Spermatogonial stem cells （SSCs） divide continuously to support spermatogenesis throughout postnatal life and transmit genetic information to the next generation. Here, we report the successful establishment of the ...Spermatogonial stem cells （SSCs） divide continuously to support spermatogenesis throughout postnatal life and transmit genetic information to the next generation. Here, we report the successful establishment of the method for the isolation and identification of human SSCs from testicular tissue, and to determine the culture conditions required to expand SSCs on human embryonic stem cell-derived fibroblast-like cells （hdFs）. Large-scale cultures of SSCs were maintained on hdF feeder layers and expanded in the presence of a combination of cytokines and glial cell line-derived neurotrophic factor for at least 2 months. Cell surface marker analysis showed that SSCs retained high levels of alkaline phosphatase activity and stained strongly for anti-stage-specific embryonic antigen （SSEA）-1, OCT4 and CD49f. They also expressed the genes OCT4, SOX3 and STRA8 as detected by reverse transcription polymerase chain reaction （RT-PCR） analysis. These data clearly illustrate a novel approach for the growth of human SSCs using hdFs as feeder cells, potentially eliminating xenogeneic contaminants. This system provides a new opportunity for the study of the regulatory mechanism of the ‘niche＇ that governs SSC self-renewal, and will be a valuable source of SSCs for potential clinical applications.展开更多
We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn un...We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications.展开更多
BACKGROUND Parthenolide(PTL),a sesquiterpene lactone derived from the medicinal herb Chrysanthemum parthenium,exhibits various biological effects by targeting NF-kB,STAT3,and other pathways.It has emerged as a promisi...BACKGROUND Parthenolide(PTL),a sesquiterpene lactone derived from the medicinal herb Chrysanthemum parthenium,exhibits various biological effects by targeting NF-kB,STAT3,and other pathways.It has emerged as a promising adjunct therapy for multiple malignancies.AIM To evaluate the in vitro and in vivo effect of PTL on cyclophosphamide(CTX)metronomic chemotherapy.METHODS The cytotoxicity of PTL and CTX on Lewis lung cancer cells(LLC cells)was assessed by measuring cell activity and apoptosis.The anti-tumor efficiency was evaluated using a tumor xenograft mice model,and the survival of mice and tumor volume were monitored.Additionally,the collected tumor tissues were analyzed for tumor microenvironment indicators and inflammatory factors.RESULTS In vitro,PTL demonstrated a synergistic effect with CTX in inhibiting the growth of LLC cells and promoting apoptosis.In vivo,metronomic chemotherapy com-bined with PTL and CTX improved the survival rate of tumor-bearing mice and reduced tumor growth rate.Furthermore,metronomic chemotherapy combined with PTL and CTX reduced NF-κB activation and improved the tumor immune microenvironment by decreasing tumor angiogenesis,reducing Transforming growth factorβ,andα-SMA positive cells.CONCLUSION PTL is an efficient compound that enhances the metronomic chemotherapy effects of CTX both in vitro and in vivo,suggesting its potential as a supplementary therapeutic strategy in metronomic chemotherapy to improve the chemotherapy effects.展开更多
Aim： To promote the provision of reproductive health services to young people by exploring the attitudes and perceptions of university students in Shanghai, China, toward reproductive health. Methods： From July 2004...Aim： To promote the provision of reproductive health services to young people by exploring the attitudes and perceptions of university students in Shanghai, China, toward reproductive health. Methods： From July 2004 to May 2006, 5 243 students from 14 universities in Shanghai took part in our survey. Topics covered the demands of reproductive health-care services, attitudes towards and experience with sex, exposure to pornographic material, and knowledge on sexual health and sexually transmitted infections （STIs）/AIDS. Results： Of the 5 067 students who provided valid answer sheets, 50.05% were female and 49.95% were male, 14.86% were medical students, and 85.14% had non-medical backgrounds. A total of 38.4% of respondents had received reproductive health education previously. The majority of students supported school-based reproductive health education, and also acquired information about sex predominantly from books, schoolmates, and the Internet. Premarital sexual behavior was opposed by 17.7% of survey participants, and 37.5% could identify all the three types of STIs listed in the questionnaire. Although 83.7% knew how HIV is transmitted, only 55.7% knew when to use a condom and 57.8% knew that the use of condoms could reduce the risk of HIV infection. Conclusion： The reproductive health service is lagging behind current attitudes and demands of university students. Although students＇ attitudes towards sexual matters are liberal, their knowledge about reproductive health and STIs/AIDS is still limited. It is therefore necessary to provide effective and confidential reproductive health services to young people.展开更多
Background: Methionine is an essential amino acid for fish. The present study was conducted to investigate the effects of dietary methionine on growth performance, digestive and absorptive ability, as well as antioxid...Background: Methionine is an essential amino acid for fish. The present study was conducted to investigate the effects of dietary methionine on growth performance, digestive and absorptive ability, as well as antioxidant capacity in the intestine and hepatopancreas of sub-adult grass carp(Ctenopharyngodon idella).Results: Dietary methionine deficiency significantly decreased percentage weight gain(PWG), feed intake, feed efficiency and protein efficiency ratio, as well as activities of hepatopancreatic glutamate-oxaloacetate transaminase and muscle glutamate-pyruvate transaminase in sub-adult grass carp(P < 0.05). Furthermore, methionine deficiency significantly reduced activities of trypsin, lipase and amylase in the intestine, Na^+/K^+-ATPase, alkaline phosphatase and γ-glutamyl transpeptidase in three intestinal segments, and creatine kinase(CK) in the proximal intestine(P < 0.05). However, an unexplained and significant increase in CK activity in the mid intestine was associated with dietary methionine deficiency. Malondialdehyde and protein carbonyl contents in the intestine and hepatopancreas were significantly increased by methionine deficiency(P < 0.05), whereas anti-hydroxyl radical capacity in the hepatopancreas and intestine, and anti-superoxide anion capacity in the intestine, were significantly decreased by methionine deficiency(P < 0.05). Moreover, methionine deficiency significantly decreased superoxide dismutase and glutathione reductase activities, glutathione contents in the hepatopancreas and intestine, as well as glutathione peroxidase activity in the intestine(P < 0.05), whereas it significantly increased activities of catalase in the hepatopancreas and glutathione-S-transferase in the hepatopancreas and intestine(P < 0.05).(Continued on next page)(Continued from previous page)Conclusions: The present results demonstrated that dietary methionine deficiency induced poor growth, and decreased digestive and absorptive function and antioxidant capacity in the hepatopancreas and intestine of sub-adult grass carp. Methionine requirements for sub-adult grass carp(450-1, 170 g) based on PWG, intestinal trypsin, and hepatopancreatic anti-hydroxyl radical activities were estimated to be 6.12 g/kg diet(21.80 g/kg protein),6.99 g/kg diet(24.90 g/kg protein) and 5.42 g/kg diet(19.31 g/kg protein), respectively, in the presence of 1.50 g cysteine/kg(5.35 g/kg protein).展开更多
AIM： To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques： combined conjunctival autograft and overlay amniotic membrane transplantation （CAT with AMT）, conjuncti...AIM： To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques： combined conjunctival autograft and overlay amniotic membrane transplantation （CAT with AMT）, conjunctival autograft transplantation （CAT） alone and amniotic membrane transplantation （AMT） alone. METHODS： In this retrospective study, 142 eyes of 142 pterygium patients （104 primary, 38 recurrent）who underwent CAT （group A）, AMT （group B） or CAT with AMT （group C） respectively following surgical excision were reviewed and compared based on the recurrences and post-operative complications. RESULTS： The number of recurrence post-surgery were 17 （9 from primary, 8 from recurrent; the same description below）, 18 （10, 8） and 2 （1, 1） in groups A, B, and C respectively; dry eyes were 22 （16, 6）, 27 （18, 9） and 7 （3, 4）; conjunctival inflammations were 30 （17, 13）, 27 （16, 11） and 11 （6, 5）. Patients in group C （either pdmary or recurrent or both） mainly showed significantly better results than those in group A or B （P〈0.05） regarding above-mentioned clinical effects. CONCLUSION： Combined CAT and overly AMT have significantly lower rates of recurrence and postoperative complications for primary and recurrent pterygium surgery than CAT or AMT alone.展开更多
Background： This study was carried out to investigate effects of threonine levels on growth, digestive and absorptive capacity and antioxidant status in intestine and hepatopancreas of sub-adult grass carp （ Ctenoph...Background： This study was carried out to investigate effects of threonine levels on growth, digestive and absorptive capacity and antioxidant status in intestine and hepatopancreas of sub-adult grass carp （ Ctenopharyngodonidella）. Results： Weight gain, specific growth rate, feed intake and feed efficiency were significantly improved by dietary threonine （P 〈 0.05）. Intestinal activities of trypsin, chymotrypsin, alpha-amylase, lipase, alkaline phosphatase, y-glutamyl transpeptidase and creatine kinase took the similar trends. Contents of malondialdehyde and protein carbonyl in intestine and hepatopancreas were significantly decreased by dietary optimal threonine supplementation （P 〈 0.05）. Anti-superoxide anion capacity, anti-hydroxyl radical capacity, glutathione content and activities of superoxide dismutase, catalase and glutathione-S-transferase in intestine and hepatopancreas were enhanced by dietary threonine （P 〈 0.05）. Conclusions： Dietary threonine could improve growth, enhance digestive and absorptive capacity and antioxidant status in intestine and hepatopancreas of sub-adult grass carp. The dietary threonine requirement of sub-adult grass carp （441.9-1,013.4 g） based on weight gain was 11.6 g/kg diet or 41.5 g/kg of dietary protein by quadratic regression analysis.展开更多
文摘Spermatogonial stem cells （SSCs） divide continuously to support spermatogenesis throughout postnatal life and transmit genetic information to the next generation. Here, we report the successful establishment of the method for the isolation and identification of human SSCs from testicular tissue, and to determine the culture conditions required to expand SSCs on human embryonic stem cell-derived fibroblast-like cells （hdFs）. Large-scale cultures of SSCs were maintained on hdF feeder layers and expanded in the presence of a combination of cytokines and glial cell line-derived neurotrophic factor for at least 2 months. Cell surface marker analysis showed that SSCs retained high levels of alkaline phosphatase activity and stained strongly for anti-stage-specific embryonic antigen （SSEA）-1, OCT4 and CD49f. They also expressed the genes OCT4, SOX3 and STRA8 as detected by reverse transcription polymerase chain reaction （RT-PCR） analysis. These data clearly illustrate a novel approach for the growth of human SSCs using hdFs as feeder cells, potentially eliminating xenogeneic contaminants. This system provides a new opportunity for the study of the regulatory mechanism of the ‘niche＇ that governs SSC self-renewal, and will be a valuable source of SSCs for potential clinical applications.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12004067,11974070,62027807,and 52272137)the National Key R&D Program of China(Grant No.2022YFA1403000)。
文摘We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications.
基金Supported by Joint Funding of Yunnan Ministry of Science and Technology,No.2019FF002-048and Beijing Heathco Clinical Oncology Research Foundation,No.Y-Q201802-048.
文摘BACKGROUND Parthenolide(PTL),a sesquiterpene lactone derived from the medicinal herb Chrysanthemum parthenium,exhibits various biological effects by targeting NF-kB,STAT3,and other pathways.It has emerged as a promising adjunct therapy for multiple malignancies.AIM To evaluate the in vitro and in vivo effect of PTL on cyclophosphamide(CTX)metronomic chemotherapy.METHODS The cytotoxicity of PTL and CTX on Lewis lung cancer cells(LLC cells)was assessed by measuring cell activity and apoptosis.The anti-tumor efficiency was evaluated using a tumor xenograft mice model,and the survival of mice and tumor volume were monitored.Additionally,the collected tumor tissues were analyzed for tumor microenvironment indicators and inflammatory factors.RESULTS In vitro,PTL demonstrated a synergistic effect with CTX in inhibiting the growth of LLC cells and promoting apoptosis.In vivo,metronomic chemotherapy com-bined with PTL and CTX improved the survival rate of tumor-bearing mice and reduced tumor growth rate.Furthermore,metronomic chemotherapy combined with PTL and CTX reduced NF-κB activation and improved the tumor immune microenvironment by decreasing tumor angiogenesis,reducing Transforming growth factorβ,andα-SMA positive cells.CONCLUSION PTL is an efficient compound that enhances the metronomic chemotherapy effects of CTX both in vitro and in vivo,suggesting its potential as a supplementary therapeutic strategy in metronomic chemotherapy to improve the chemotherapy effects.
文摘Aim： To promote the provision of reproductive health services to young people by exploring the attitudes and perceptions of university students in Shanghai, China, toward reproductive health. Methods： From July 2004 to May 2006, 5 243 students from 14 universities in Shanghai took part in our survey. Topics covered the demands of reproductive health-care services, attitudes towards and experience with sex, exposure to pornographic material, and knowledge on sexual health and sexually transmitted infections （STIs）/AIDS. Results： Of the 5 067 students who provided valid answer sheets, 50.05% were female and 49.95% were male, 14.86% were medical students, and 85.14% had non-medical backgrounds. A total of 38.4% of respondents had received reproductive health education previously. The majority of students supported school-based reproductive health education, and also acquired information about sex predominantly from books, schoolmates, and the Internet. Premarital sexual behavior was opposed by 17.7% of survey participants, and 37.5% could identify all the three types of STIs listed in the questionnaire. Although 83.7% knew how HIV is transmitted, only 55.7% knew when to use a condom and 57.8% knew that the use of condoms could reduce the risk of HIV infection. Conclusion： The reproductive health service is lagging behind current attitudes and demands of university students. Although students＇ attitudes towards sexual matters are liberal, their knowledge about reproductive health and STIs/AIDS is still limited. It is therefore necessary to provide effective and confidential reproductive health services to young people.
基金supported by the National Basic Research Program of China(973 Program)(2014CB138600)National Science Foundation of China(31502184)+7 种基金Outstanding Talents and Innovative Team of Agricultural Scientific Research(Ministry of Agriculture)the National Department Public Benefit Research Foundation(Agriculture)of China(201003020)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20135103110001)Science and Technology Support Program of Sichuan Province of China(2014NZ0003)Major Scientific and Technological Achievement Transformation Project of Sichuan Province of China(2012NC00072013NC0045)the Demonstration of Major Scientific and Technological Achievement Transformation Project of Sichuan Province of China(2015CC0011)Natural Science Foundation for Young Scientists of Sichuan Province(2014JQ0007)
文摘Background: Methionine is an essential amino acid for fish. The present study was conducted to investigate the effects of dietary methionine on growth performance, digestive and absorptive ability, as well as antioxidant capacity in the intestine and hepatopancreas of sub-adult grass carp(Ctenopharyngodon idella).Results: Dietary methionine deficiency significantly decreased percentage weight gain(PWG), feed intake, feed efficiency and protein efficiency ratio, as well as activities of hepatopancreatic glutamate-oxaloacetate transaminase and muscle glutamate-pyruvate transaminase in sub-adult grass carp(P < 0.05). Furthermore, methionine deficiency significantly reduced activities of trypsin, lipase and amylase in the intestine, Na^+/K^+-ATPase, alkaline phosphatase and γ-glutamyl transpeptidase in three intestinal segments, and creatine kinase(CK) in the proximal intestine(P < 0.05). However, an unexplained and significant increase in CK activity in the mid intestine was associated with dietary methionine deficiency. Malondialdehyde and protein carbonyl contents in the intestine and hepatopancreas were significantly increased by methionine deficiency(P < 0.05), whereas anti-hydroxyl radical capacity in the hepatopancreas and intestine, and anti-superoxide anion capacity in the intestine, were significantly decreased by methionine deficiency(P < 0.05). Moreover, methionine deficiency significantly decreased superoxide dismutase and glutathione reductase activities, glutathione contents in the hepatopancreas and intestine, as well as glutathione peroxidase activity in the intestine(P < 0.05), whereas it significantly increased activities of catalase in the hepatopancreas and glutathione-S-transferase in the hepatopancreas and intestine(P < 0.05).(Continued on next page)(Continued from previous page)Conclusions: The present results demonstrated that dietary methionine deficiency induced poor growth, and decreased digestive and absorptive function and antioxidant capacity in the hepatopancreas and intestine of sub-adult grass carp. Methionine requirements for sub-adult grass carp(450-1, 170 g) based on PWG, intestinal trypsin, and hepatopancreatic anti-hydroxyl radical activities were estimated to be 6.12 g/kg diet(21.80 g/kg protein),6.99 g/kg diet(24.90 g/kg protein) and 5.42 g/kg diet(19.31 g/kg protein), respectively, in the presence of 1.50 g cysteine/kg(5.35 g/kg protein).
基金Supported by Natural Science Foundation of Jiangsu Province(No.BK20141346)Nanjing Science and Technology Development Plan(No.201402001)
文摘AIM： To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques： combined conjunctival autograft and overlay amniotic membrane transplantation （CAT with AMT）, conjunctival autograft transplantation （CAT） alone and amniotic membrane transplantation （AMT） alone. METHODS： In this retrospective study, 142 eyes of 142 pterygium patients （104 primary, 38 recurrent）who underwent CAT （group A）, AMT （group B） or CAT with AMT （group C） respectively following surgical excision were reviewed and compared based on the recurrences and post-operative complications. RESULTS： The number of recurrence post-surgery were 17 （9 from primary, 8 from recurrent; the same description below）, 18 （10, 8） and 2 （1, 1） in groups A, B, and C respectively; dry eyes were 22 （16, 6）, 27 （18, 9） and 7 （3, 4）; conjunctival inflammations were 30 （17, 13）, 27 （16, 11） and 11 （6, 5）. Patients in group C （either pdmary or recurrent or both） mainly showed significantly better results than those in group A or B （P〈0.05） regarding above-mentioned clinical effects. CONCLUSION： Combined CAT and overly AMT have significantly lower rates of recurrence and postoperative complications for primary and recurrent pterygium surgery than CAT or AMT alone.
基金National 973 Project of China(2014CB138600)National Department Public Benefit Research Foundation(Agriculture) of China (201003020)+1 种基金Science and Technology Support Programme of Sichuan Province of China(2014NZ0003)Major Scientific and Technological Achievement Transformation Project of Sichuan Province of China(2012NC0007 and 2013NC0045) for their financial support
文摘Background： This study was carried out to investigate effects of threonine levels on growth, digestive and absorptive capacity and antioxidant status in intestine and hepatopancreas of sub-adult grass carp （ Ctenopharyngodonidella）. Results： Weight gain, specific growth rate, feed intake and feed efficiency were significantly improved by dietary threonine （P 〈 0.05）. Intestinal activities of trypsin, chymotrypsin, alpha-amylase, lipase, alkaline phosphatase, y-glutamyl transpeptidase and creatine kinase took the similar trends. Contents of malondialdehyde and protein carbonyl in intestine and hepatopancreas were significantly decreased by dietary optimal threonine supplementation （P 〈 0.05）. Anti-superoxide anion capacity, anti-hydroxyl radical capacity, glutathione content and activities of superoxide dismutase, catalase and glutathione-S-transferase in intestine and hepatopancreas were enhanced by dietary threonine （P 〈 0.05）. Conclusions： Dietary threonine could improve growth, enhance digestive and absorptive capacity and antioxidant status in intestine and hepatopancreas of sub-adult grass carp. The dietary threonine requirement of sub-adult grass carp （441.9-1,013.4 g） based on weight gain was 11.6 g/kg diet or 41.5 g/kg of dietary protein by quadratic regression analysis.
