Aim： To simultaneously determine the localization of histones and protamines within human sperm nuclei. Methods： Immunofluorescence of the core histones and protamines and fluorescence in situ hybridization of the t...Aim： To simultaneously determine the localization of histones and protamines within human sperm nuclei. Methods： Immunofluorescence of the core histones and protamines and fluorescence in situ hybridization of the telomere region of chromosome 16 was assessed in decondensed human sperm nuclei. Results： Immunofluorescent localization of histones, protamine 1 （PRM1） and protamine 2 （PRM2） along with fluorescence in situ hybridization localization of chromosome 16 telomeric sequences revealed a discrete distribution in sperm nuclei. Histones localized to the posterior ring region （i.e. the sperm nuclear annulus）, whereas PRM1 and PRM2 appeared to be dispersed throughout the entire nucleus. Conclusion： The co-localization of the human core sperm histones with the telomeric regions of chromosome 16 is consistent with the reorganization of specific non-protamine regions into a less compacted state.展开更多
为了实现鲢鱼加工副产物的高效综合利用,以鲢鱼精巢为原料,研究柠檬酸浓度、提取温度、超声功率、提取时间、固液比、提取次数对鱼精蛋白得率的影响。在单因素试验基础上,通过正交试验获得最佳提取工艺为:柠檬酸浓度0.45mol/L,温度55℃...为了实现鲢鱼加工副产物的高效综合利用,以鲢鱼精巢为原料,研究柠檬酸浓度、提取温度、超声功率、提取时间、固液比、提取次数对鱼精蛋白得率的影响。在单因素试验基础上,通过正交试验获得最佳提取工艺为:柠檬酸浓度0.45mol/L,温度55℃,超声时间20min,超声功率400 W,固液比130(g/mL),提取3次。在最佳工艺条件下,鱼精蛋白得率为3.25%;鱼精粗蛋白经Sepharose Fast Flow离子交换层析分离得到4个组分,对4个组分进行抗菌性分析可知,除鱼精蛋白的前体蛋白外,其他组分对沙门氏菌、金黄色葡萄球菌和大肠杆菌均具有较好的抑制活性,其中组分II、III的抑菌活性较好。展开更多
Several studies have compared prostate-specific antigen （PSA） kinetics in men with and without cancer, but there has been no adequate analysis of the longitudinal variation in PSA. The aim of this study was to asses...Several studies have compared prostate-specific antigen （PSA） kinetics in men with and without cancer, but there has been no adequate analysis of the longitudinal variation in PSA. The aim of this study was to assess the fluctuations in PSA in a cohort of elderly men in an attempt to define a physiological pattern of PSA kinetics. We searched a specific cohort of patients aged 〉 75 years and with PSA value 〈 2.0 ng mL^-1. A history of all PSA values over the past 10 years was compiled for each patient to create a database of patients fitting the following criteria： （1） minimum of five PSA measurements, （2） over at least 5 years. Exclusion criteria were： （1） PSA 〈 0.2 ng mL^-1 at each measurement and （2） having had more than one PSA test per year. In all, 1 327 patients （mean age： 78.52 years） fit the inclusion criteria. The mean variation from the first to the last PSA test was 0.05 ± 0.43, with a mean follow-up of 6.79 ± 1.71 years. Over the same period, the mean fluctuation from the lowest to the highest PSA value was 0.04 ± 0.55 （P = 0.925）. The mean annual PSA velocity （PSAV） was calculated by dividing the mean variation from the first to the last PSA test by the number of years of observation for each patient and was set at 0.0104 ± 0.1050. Concluding, in a large-scale cohort of elderly individuals considered healthy and evaluated for a considerable follow-up, the average annual PSAV as well as the average fluctuation from the lowest to the highest PSA value are insignificant.展开更多
大量遗传学研究表明,Piwi蛋白对于动物生殖系细胞发育具有至关重要的作用,Piwi基因敲除致动物不育。人Piwi(Hiwi)基因特异性地在雄性生殖细胞表达,但目前对其在人精子发生中的作用及其与男性不育的联系还知之甚少。该研究通过筛查临床...大量遗传学研究表明,Piwi蛋白对于动物生殖系细胞发育具有至关重要的作用,Piwi基因敲除致动物不育。人Piwi(Hiwi)基因特异性地在雄性生殖细胞表达,但目前对其在人精子发生中的作用及其与男性不育的联系还知之甚少。该研究通过筛查临床男性不育样本发现,少弱精症患者Hiwi基因中存在拮抗泛素化修饰的D-box元件突变;通过构建基因敲入小鼠模型证实,该突变导致雄性不育。机制研究表明,小鼠Piwi(Miwi)D-box突变致MIWI蛋白异常稳定存在于后期精子细胞中,导致与其相互作用的组蛋白泛素连接酶RNF8(ring finger protein 8)被扣留于细胞质、不能入核催化组蛋白泛素化修饰,进而抑制组蛋白被鱼精蛋白替换,引发精子形成异常、雄性不育。该研究发现了男性不育的一类新型致病基因突变,并发现了Piwi蛋白具有调控组蛋白泛素化修饰的新功能,揭示了精子形成中调控组蛋白–鱼精蛋白转换的重要机制。展开更多
文摘Aim： To simultaneously determine the localization of histones and protamines within human sperm nuclei. Methods： Immunofluorescence of the core histones and protamines and fluorescence in situ hybridization of the telomere region of chromosome 16 was assessed in decondensed human sperm nuclei. Results： Immunofluorescent localization of histones, protamine 1 （PRM1） and protamine 2 （PRM2） along with fluorescence in situ hybridization localization of chromosome 16 telomeric sequences revealed a discrete distribution in sperm nuclei. Histones localized to the posterior ring region （i.e. the sperm nuclear annulus）, whereas PRM1 and PRM2 appeared to be dispersed throughout the entire nucleus. Conclusion： The co-localization of the human core sperm histones with the telomeric regions of chromosome 16 is consistent with the reorganization of specific non-protamine regions into a less compacted state.
文摘为了实现鲢鱼加工副产物的高效综合利用,以鲢鱼精巢为原料,研究柠檬酸浓度、提取温度、超声功率、提取时间、固液比、提取次数对鱼精蛋白得率的影响。在单因素试验基础上,通过正交试验获得最佳提取工艺为:柠檬酸浓度0.45mol/L,温度55℃,超声时间20min,超声功率400 W,固液比130(g/mL),提取3次。在最佳工艺条件下,鱼精蛋白得率为3.25%;鱼精粗蛋白经Sepharose Fast Flow离子交换层析分离得到4个组分,对4个组分进行抗菌性分析可知,除鱼精蛋白的前体蛋白外,其他组分对沙门氏菌、金黄色葡萄球菌和大肠杆菌均具有较好的抑制活性,其中组分II、III的抑菌活性较好。
文摘Several studies have compared prostate-specific antigen （PSA） kinetics in men with and without cancer, but there has been no adequate analysis of the longitudinal variation in PSA. The aim of this study was to assess the fluctuations in PSA in a cohort of elderly men in an attempt to define a physiological pattern of PSA kinetics. We searched a specific cohort of patients aged 〉 75 years and with PSA value 〈 2.0 ng mL^-1. A history of all PSA values over the past 10 years was compiled for each patient to create a database of patients fitting the following criteria： （1） minimum of five PSA measurements, （2） over at least 5 years. Exclusion criteria were： （1） PSA 〈 0.2 ng mL^-1 at each measurement and （2） having had more than one PSA test per year. In all, 1 327 patients （mean age： 78.52 years） fit the inclusion criteria. The mean variation from the first to the last PSA test was 0.05 ± 0.43, with a mean follow-up of 6.79 ± 1.71 years. Over the same period, the mean fluctuation from the lowest to the highest PSA value was 0.04 ± 0.55 （P = 0.925）. The mean annual PSA velocity （PSAV） was calculated by dividing the mean variation from the first to the last PSA test by the number of years of observation for each patient and was set at 0.0104 ± 0.1050. Concluding, in a large-scale cohort of elderly individuals considered healthy and evaluated for a considerable follow-up, the average annual PSAV as well as the average fluctuation from the lowest to the highest PSA value are insignificant.
文摘大量遗传学研究表明,Piwi蛋白对于动物生殖系细胞发育具有至关重要的作用,Piwi基因敲除致动物不育。人Piwi(Hiwi)基因特异性地在雄性生殖细胞表达,但目前对其在人精子发生中的作用及其与男性不育的联系还知之甚少。该研究通过筛查临床男性不育样本发现,少弱精症患者Hiwi基因中存在拮抗泛素化修饰的D-box元件突变;通过构建基因敲入小鼠模型证实,该突变导致雄性不育。机制研究表明,小鼠Piwi(Miwi)D-box突变致MIWI蛋白异常稳定存在于后期精子细胞中,导致与其相互作用的组蛋白泛素连接酶RNF8(ring finger protein 8)被扣留于细胞质、不能入核催化组蛋白泛素化修饰,进而抑制组蛋白被鱼精蛋白替换,引发精子形成异常、雄性不育。该研究发现了男性不育的一类新型致病基因突变,并发现了Piwi蛋白具有调控组蛋白泛素化修饰的新功能,揭示了精子形成中调控组蛋白–鱼精蛋白转换的重要机制。
