Objective To explore and quantify the association of hot night exposure during the sperm development period(0–90 lag days) with semen quality.Methods A total of 6,640 male sperm donors from 6 human sperm banks in Chi...Objective To explore and quantify the association of hot night exposure during the sperm development period(0–90 lag days) with semen quality.Methods A total of 6,640 male sperm donors from 6 human sperm banks in China during 2014–2020were recruited in this multicenter study.Two indices(i.e.,hot night excess [HNE] and hot night duration[HND]) were used to estimate the heat intensity and duration during nighttime.Linear mixed models were used to examine the association between hot nights and semen quality parameters.Results The exposure-response relationship revealed that HNE and HND during 0–90 days before semen collection had a significantly inverse association with sperm motility.Specifically,a 1 ℃ increase in HNE was associated with decreased sperm progressive motility of 0.0090(95% confidence interval[CI]:–0.0147,–0.0033) and decreased total motility of 0.0094(95% CI:–0.0160,–0.0029).HND was significantly associated with reduced sperm progressive motility and total motility of 0.0021(95% CI:–0.0040,–0.0003) and 0.0023(95% CI:–0.0043,–0.0002),respectively.Consistent results were observed at different temperature thresholds on hot nights.Conclusion Our findings highlight the need to mitigate nocturnal heat exposure during spermatogenesis to maintain optimal semen quality.展开更多
Research in stem cells is one of the most rapidly evolving fields of investigation in medicine today. Stem cells are defined as cells that have the capacity to both generate daughter cells identical to the cell of ori...Research in stem cells is one of the most rapidly evolving fields of investigation in medicine today. Stem cells are defined as cells that have the capacity to both generate daughter cells identical to the cell of origin (self-renewal) and to produce progeny with more restricted, specialized potential (differentiated cells). This dual ability to self-renew and differentiate offers great promise for expanding our understanding of organ systems, elucidating disease pathophysiology, and creating therapeutic approaches to difficult diseases. The goal of this review is to offer an overview of the different types of stem cells and to provide an introduction to the applications of stem cells to the field of obstetrics and gynecology.展开更多
基金funded by the Guangdong Provincial Natural Science Foundation of China(No.2022A1515011517).
文摘Objective To explore and quantify the association of hot night exposure during the sperm development period(0–90 lag days) with semen quality.Methods A total of 6,640 male sperm donors from 6 human sperm banks in China during 2014–2020were recruited in this multicenter study.Two indices(i.e.,hot night excess [HNE] and hot night duration[HND]) were used to estimate the heat intensity and duration during nighttime.Linear mixed models were used to examine the association between hot nights and semen quality parameters.Results The exposure-response relationship revealed that HNE and HND during 0–90 days before semen collection had a significantly inverse association with sperm motility.Specifically,a 1 ℃ increase in HNE was associated with decreased sperm progressive motility of 0.0090(95% confidence interval[CI]:–0.0147,–0.0033) and decreased total motility of 0.0094(95% CI:–0.0160,–0.0029).HND was significantly associated with reduced sperm progressive motility and total motility of 0.0021(95% CI:–0.0040,–0.0003) and 0.0023(95% CI:–0.0043,–0.0002),respectively.Consistent results were observed at different temperature thresholds on hot nights.Conclusion Our findings highlight the need to mitigate nocturnal heat exposure during spermatogenesis to maintain optimal semen quality.
文摘Research in stem cells is one of the most rapidly evolving fields of investigation in medicine today. Stem cells are defined as cells that have the capacity to both generate daughter cells identical to the cell of origin (self-renewal) and to produce progeny with more restricted, specialized potential (differentiated cells). This dual ability to self-renew and differentiate offers great promise for expanding our understanding of organ systems, elucidating disease pathophysiology, and creating therapeutic approaches to difficult diseases. The goal of this review is to offer an overview of the different types of stem cells and to provide an introduction to the applications of stem cells to the field of obstetrics and gynecology.
