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1.
Heat stress (HS) is a notable risk factor for female reproductive performance. In particular, impaired oocyte maturation was thought to contribute largely to the HS-induced reproductive dysfunctions. In this study, we confirmed that oocytes undergoing GVBD were much susceptible to HS, and thus compromising subsequent embryonic development. Using N-acetyl-l-cysteine (NAC), we found supplementation of a relatively high dose NAC during in vitro maturation, can protect oocytes from HS-induced complications, and thus rescuing impaired embryonic development. Further analysis indicated that mechanisms responsible for protecting GVBD oocytes from HS by NAC may include: (1) reversing disorganized spindle assembly and inhibited extracellular signal–regulated kinase (ERK) signaling; (2) correcting erroneous H3K27me3 modification and dysregulated expression of imprinted genes; (3) alleviating increased intraoocyte reactive oxygen species accumulation and apoptosis initiation. Our study, focusing on the oocyte meiotic maturation, may provide a safe and promising strategy for protecting reproductive sows under environmental hyperthermal conditions. 相似文献
2.
目的比较双球囊与缩宫素用于促宫颈成熟并引产的临床效果。方法选取于2017年7月—2018年7月在本院分娩的足月妊娠孕妇100例为研究对象,随机平均分为观察组和对照组各50例,观察组采用双球囊引产,对照组采用缩宫素进行引产,对比2组孕妇的总产程、宫颈成熟度、引产成功率和新生儿Apgar评分、并发症发生率等。结果观察组促宫颈成熟有效率(100%)、引产成功率(96%)均高于对照组(82%,74%),差异均有统计学意义(P<0.05),治疗后新生儿Apgar评分、并发症发生率差异均无统计学意义(P>0.05);宫颈Bishop评分观察组(9.12±1.42)高于对照组(7.92±1.56),观察组总产程(8.23±2.54)h,对照组(13.45±3.77)h,差异均有统计学意义(P<0.05)。结论双球囊用于妊娠引产效果显著,能明显促进宫颈成熟、缩短产程,保障分娩的顺利进行,安全可靠,值得在临床中推广。 相似文献
3.
Sheng Zhang Yan Wang Jie Xu Bokyung Kim Wenbin Deng Fuzheng Guo 《The Journal of neuroscience》2021,41(2):251
The developing CNS is exposed to physiological hypoxia, under which hypoxia-inducible factor α (HIFα) is stabilized and plays a crucial role in regulating neural development. The cellular and molecular mechanisms of HIFα in developmental myelination remain incompletely understood. A previous concept proposes that HIFα regulates CNS developmental myelination by activating the autocrine Wnt/β-catenin signaling in oligodendrocyte progenitor cells (OPCs). Here, by analyzing a battery of genetic mice of both sexes, we presented in vivo evidence supporting an alternative understanding of oligodendroglial HIFα-regulated developmental myelination. At the cellular level, we found that HIFα was required for developmental myelination by transiently controlling upstream OPC differentiation but not downstream oligodendrocyte maturation and that HIFα dysregulation in OPCs but not oligodendrocytes disturbed normal developmental myelination. We demonstrated that HIFα played a minor, if any, role in regulating canonical Wnt signaling in the oligodendroglial lineage or in the CNS. At the molecular level, blocking autocrine Wnt signaling did not affect HIFα-regulated OPC differentiation and myelination. We further identified HIFα–Sox9 regulatory axis as an underlying molecular mechanism in HIFα-regulated OPC differentiation. Our findings support a concept shift in our mechanistic understanding of HIFα-regulated CNS myelination from the previous Wnt-dependent view to a Wnt-independent one and unveil a previously unappreciated HIFα–Sox9 pathway in regulating OPC differentiation.SIGNIFICANCE STATEMENT Promoting disturbed developmental myelination is a promising option in treating diffuse white matter injury, previously called periventricular leukomalacia, a major form of brain injury affecting premature infants. In the developing CNS, hypoxia-inducible factor α (HIFα) is a key regulator that adapts neural cells to physiological and pathologic hypoxic cues. The role and mechanism of HIFα in oligodendroglial myelination, which is severely disturbed in preterm infants affected with diffuse white matter injury, is incompletely understood. Our findings presented here represent a concept shift in our mechanistic understanding of HIFα-regulated developmental myelination and suggest the potential of intervening with an oligodendroglial HIFα-mediated signaling pathway to mitigate disturbed myelination in premature white matter injury. 相似文献
4.
5.
刺五加水提物对人精子体外运动活力的影响 总被引:5,自引:0,他引:5
目的研究刺五加水提物对正常男性精子体外运动活力的影响,探讨其可能的作用机制。方法将20例正常男性的精子通过上游优化法处理后,一组精子加入10 mg·mL-1的刺五加水提物,另一组加入等量的Ham’s F10培养液作对照。应用计算机辅助的精子分析系统,分别测定孵育0.5,1,2,3,4,5 h后人精子各运动参数。结果随着时间的延长,加入Ham’s F10培养液的精子活动能力有不同程度的下降;加入10 mg·mL-1的刺五加水提物后,不同时段精子的运动能力均较对照组明显提高,精子存活率、前向运动精子百分率、曲线运动速度、直线运动速度和平均路径速度与对照组比较,均明显改善(均P<0.05)。 结论刺五加水提物能明显提高正常男性精子的体外存活率和运动能力。 相似文献
6.
BARI NUHOLU ALI AYYILDIZ VECIHI FIDAN ÖZDEN CEBECI UUR KOAR CANKON GERMIYANOLU 《International journal of urology》2006,13(2):109-110
OBJECTIVE: Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In recent years, various studies have been published stating that children with nocturnal enuresis exhibit growth and skeletal maturation retardation. METHODS: In this cross-sectional study, we included 27 patients (16 boys, 11 girls) between the ages of 6 and 14 years who had presented with primary nocturnal enuresis (PNE) complaints. We included in the evaluation 19 healthy subjects (12 boys, 7 girls), who were the siblings of the children with PNE, as the control group. RESULTS: The patients in both groups were similar in chronological age, bone age, height and weight, with no significant difference between groups (P>0.05). CONCLUSION: The two groups in our study consisted of the same genetic background. Thus, our results were found to be different from the previous studies. We have concluded that there is no direct relationship between enuresis nocturnal and skeletal maturation. 相似文献
7.
A Espinosa de los Monteros G Roussel N M Neskovic J L Nussbaum 《Journal of neuroscience research》1988,19(2):202-211
A new chemically defined medium consisting of equal parts of Dulbecco modified Eagle's and Ham's F-12 media supplemented with insulin, sodium selenite, putrescine, and D+ galactose, which allows the long-term survival of mature oligodendrocyte pure cultures, is described. Immunohistochemical staining has shown that over 90% of the cells become positive for myelin proteins shortly following subculture. Contaminating astrocytes (2%) do not survive in this medium. Biochemical data have indicated that these purified oligodendrocytes express 2'3'-cyclic nucleotide 3'-phosphohydrolase and UDP-galactose ceramide galactosyltransferase activities. Electron microscopical examination revealed that the oligodendrocytes were mostly of medium-dark type and appeared to be identical to cells cultured in serum-containing medium. The ability to maintain pure oligodendrocyte cultures in such a defined medium will allow investigations concerning exogenous and endogenous factors involved in oligodendrocyte metabolism. 相似文献
8.
P. Hyttel 《Anatomy and embryology》1987,176(1):41-44
Summary Cumulus-oocyte complexes were obtained from cows by aspiration of small (1–6 mm in diameter) antral follicles after slaughter. Complexes with a compact multilayered cumulus investment were cultured and processed for transmission electron microscopy after different periods of culture including a 0 h control group. In 0 h control oocytes the cumulus cells had numerous projections which penetrated the zona pellucida and established gap junctions with the oolemma. A partial loss of these junctions was noticed as an early event of oocyte maturation occurring within the first 3 h of culture. A low frequency of gap junctions was maintained until 12–18 h of culture where the junctional contact was completely disrupted. This decrease in intercellular communication was parallelled by resumption of oocyte meiosis. 相似文献
9.
目的应用人精子头-尾膜完整性试验,比较生育力组与不育组男性精液4种精子膜完整性类型的差异.方法精液标本分为生育力组(n=32)和不育组(n=50),采用"低渗肿胀-伊红拒染"结合试验,检测人精子头-尾膜完整性.结果头膜尾膜均损伤的Ⅰ型精子和头膜损伤-尾膜完整的Ⅲ型精子,生育组和不育组存在明显差异(P<0.01);头膜完整-尾膜损伤的Ⅱ型精子,生育组和不育组无明显差异(P>0.05);头膜-尾膜均完整的Ⅳ型精子,生育组明显高于不育组(P<0.01);Ⅳ型精子率与生育组精子活动率(n=32, r=0.82,P<0.01)和不育组精子活动率(n=50,r=0.80,P<0.01)均呈显著相关性.结论生育组具有较多头膜-尾膜均完整的精子."低渗肿胀-伊红拒染"结合试验能够清晰显示包括过渡型膜损伤的4种膜完整性类型的精子,精子头-尾膜完整性可以作为评价精子生理学的一项检测指标. 相似文献
10.
P. Cavalla V. Rovei S. Masera M. Vercellino M. Massobrio R. Mutani A. Revelli 《Neurological sciences》2006,27(4):231-239
Abstract The issue of fertility in patients with multiple sclerosis (MS) has not been exhaustively studied. Epidemiological data have
suggested that spontaneous fecundity might be reduced; several endocrine and sexual disturbances potentially interfering with
reproduction have been evidenced in MS patients of both sexes. Moreover, some medical treatments used in MS (e. g., mitoxantrone,
cyclophosphamide) may exert detrimental effects on spermatozoa as well as on oocytes, leading to early impairment of fertility.
This review illustrates the factors potentially interfering with fertility in MS and discusses the therapeutic tools that
may be used to promote fertility in these patients. The safety of hormonal therapies in MS is also examined. The current applications
of assisted reproductive technology (ART) are discussed, including in vitro fertilisation (IVF) techniques. Currently available methods to preserve fertility in patients that undergo cytotoxic treatments
by means of sperm/oocyte cryostorage or by ovarian fragment cryopreservation and autografting are considered. 相似文献