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161.
《Reproductive biology》2021,21(4):100563
Increased production of reactive oxygen species (ROS) in granulosa cells (GCs) causes oxidative stress (OS) and plays a role in pathogenesis of polycystic ovary syndrome (PCOS). Sulforaphane (SFN) has received a great deal of attention as potent antioxidant because of its ability to induce expression of antioxidant enzymes through nuclear factor (erythroid-derived 2)-like 2 (NRF2) signaling pathway. Therefore, the present study was done to investigate the protective effect of SFN against OS in granulosa-lutein cells (GLCs) of patients with PCOS through activation of AMP-activated protein kinase (AMPK)/AKT/NRF2 signaling pathway. GLCs were isolated from patients with PCOS and healthy fertile women, as control group, during egg retrieval procedure. Level of intracellular ROS and apoptosis was determined in the isolated cells. For investigating the protective effect of SFN against ROS production and apoptosis in GLCs, the cells were cultured for 24 h in the presence or absence of SFN. Finally, expression of AMPK, AKT, and NRF2 proteins and genes was evaluated by western blotting and quantitative real-time polymerase chain reaction (qRT-PCR), respectively. The results indicated the increased ROS and apoptosis levels in GLCs isolated from patients with PCOS compared to the control group. Addition of SFN to culture medium of GLCs of patients with PCOS reduced intracellular ROS and apoptosis levels, and increased expression of AMPK, AKT, and NRF2 proteins and genes. Our findings demonstrated the protective effect of SFN against OS by lowering level of ROS and apoptosis possibly through activation of AMPK, AKT, and NRF2 proteins and genes expression.  相似文献   
162.
目的:探讨盆腔瘀血综合征患者彩色多普勒超声的影像学特征及与临床因素的相关性。方法:对112例盆腔瘀血综合征患者行彩色多普勒超声检查,按超声诊断分级Ⅰ级、Ⅱ级、Ⅲ级分为62例、27例、23例,观察彩色多普勒超声的影像学特征,分析静脉内径与病程的相关性,并分析超声诊断分级与临床症状积分、体质量指数(BMI)、妊娠次数、既往工作站立时间的相关性。结果:不同超声诊断分级患者的静脉内径、静脉丛范围和静脉流速差异具有统计学意义(P<0.05)。静脉内径与病程呈正相关(P<0.05),超声诊断分级与临床症状积分、妊娠次数、既往工作站立时间呈显著正相关(P<0.05),与BMI呈负相关(P<0.05)。结论:彩色多普勒超声对盆腔瘀血综合征具有特异性的诊断价值,超声诊断分级、静脉内径与临床因素存在一定的的关联性。  相似文献   
163.
《遗传学报》2021,48(12):1104-1110
Identification of carriers of fragile X syndrome (FXS) with the subsequent prenatal diagnosis and knowledge of FXS-associated genetic profiles are essential for intervention in specific populations. We report the results of carrier screening of 39,458 East Asian adult women and prenatal diagnosis from 87 FXS carriers. The prevalence of FXS carriers and full mutation fetuses was estimated to be 1/581 and 1/3124 in East Asian populations, respectively. We confirmed the validity of the current threshold of CGG trinucleotide repeats for FMR1 categorization; the integral risks of full mutation expansion were approximately 6.0%, 43.8%, and 100% for premutation alleles with 55–74, 75–89, and ≥ 90 CGG repeats, respectively. The protective effect of AGG (adenine-guanine-guanine nucleotides) interruption in East Asian populations was validated, which is important in protecting premutation alleles with 75–89 CGG repeats from full mutation expansion. Finally, family history was shown not an effective indicator for FXS carrier screening in East Asian populations, and population-based screening was more cost-effective. This study provides an insight into the largest carrier screening and prenatal diagnosis for FXS in East Asian populations to date. The FXS-associated genetic profiles of East Asian populations are delineated, and population-based carrier screening is shown to be promising for FXS intervention.  相似文献   
164.
全球传粉昆虫多样性正在下降, 如何保障农林生态系统传粉功能是当前研究的热点。理论上说, 传粉功能不仅与生态系统的传粉昆虫多样性相关, 还与生态系统的调节能力有关。近年来, 学者们逐渐认识到授粉生态弹性对传粉功能的影响。本文在回顾已有研究的基础之上, 总结传粉昆虫授粉生态弹性的内涵, 厘清授粉生态弹性与工程弹性、稳定性和抗性的异同。目前, 学者对授粉生态弹性形成机制开展广泛探讨, 提出功能冗余假说、密度补偿假说、响应多样性假说、连接周转假说和跨尺度弹性假说, 但这5个假说间的关系仍不清楚, 存在一词多义、词意混淆等现象。我们依次阐述功能冗余假说、密度补偿假说、响应多样性假说、连接周转假说和跨尺度弹性假说, 介绍不同假说中授粉生态弹性形成过程、研究热点和发展动态。通过解析授粉生态弹性的形成机制可知, 5个假说在内涵上存在紧密联系, 它们从不同空间尺度和研究对象下解释传粉昆虫授粉生态弹性的形成机制。未来授粉生态弹性研究将整合传粉昆虫群落动态和传粉功能动态的量化方法, 通过实验验证5个假说的合理性, 并揭示不同假说间的联系, 由此阐明授粉生态弹性的发生条件、形成阈值和动态规律。随着研究的深入, 授粉生态弹性理论有望用于指导农林生态系统传粉功能的经营管理。  相似文献   
165.
目的比较多囊卵巢综合征(PCOS)患者与健康人群间肠道菌群的差异,为后续研究提供参考。方法采用16S rDNA扩增子测序法对30例PCOS患者(PCOS组)和20例健康人(健康组)粪便标本中菌群结构进行分析,并比较两组之间的区别。结果与健康组相比,PCOS组患者肠道菌群α多样性降低。PCOS组患者肠道厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)丰度高于健康组,拟杆菌门(Bacteroidetes)丰度低于健康组(均P0.05)。两组对象肠道梭菌门(Clostridia)、放线菌门(Actinobacteria)丰度差异无统计学意义(均P0.05)。PCOS组患者肠道变形杆菌纲(Proteobacteria)、芽胞杆菌纲(Bacilli)、红椿杆菌纲(Coriobacteriia)丰度高于健康组,拟杆菌纲(Bacteroidia)丰度低于健康组(均P0.05)。PCOS组患者肠道布劳特菌属(Blautia)、霍氏真杆菌属(Eubacterium_hallii_group)、阴沟杆菌属(Agathobacter)丰度高于健康组,拟杆菌属(Bacteroides)、粪杆菌属(Faecalibacterium)丰度低于健康组(均P0.05)。两组对象肠道双歧杆菌属(Bifidobacterium)、埃希菌-志贺菌属(Escherichia-Shigella)丰度差异无统计学意义(均P0.05)。结论 PCOS患者存在肠道菌群失调情况,但其是否是PCOS发展的潜在致病因素需要进一步研究。  相似文献   
166.
Habenaria is one of the largest terrestrial genera in the family Orchidaceae. Most field studies on Habenaria species with greenish–white and nocturnal scented flowers are pollinated by nocturnal hawkmoths and settling moths. However, H. rhodocheila presents reddish flowers lacking a detectable scent and fails to fit the moth pollination syndrome. We investigated the pollinators, breeding system, and functional traits of H. rhodocheila in South China and found that two diurnal swallowtail butterflies Papilio helenus and Papilio nephelus (Papilionidae) were the effective pollinators. When butterflies foraged for nectar in the spur, the pollinia became attached between the palpi. A triangular projected median rostellar lobe was found at the entrance (sinus) of the spur of H. rhodocheila. This lobe divided the spur opening into two entrances forcing butterflies to enter their proboscides through the left or right side. When the projection of median rostellar lobe was removed, the site of pollinium attachment changed to the eyes of the butterflies, leading to a higher rate of pollinium removal but lower rate of pollinium deposition. Our quartz glass cylinder choice experiment suggested that visual rather than olfactory cues provided the major stimuli for butterflies to locate these flowers. Hand pollination experiments suggested this species was self‐compatible but pollinator‐dependent. However, the proportion of seeds with large embryos produced in self‐pollinated fruits was significantly lower than in cross‐pollinated fruits, indicating a significant inbreeding depression. Unlike many other orchid species, fruit set was higher than rates of pollinium removal, indicating a high level of pollination efficiency in a species with friable pollinia. Shifts from moth to butterfly pollination in the genus Habenaria parallel other orchid lineages providing insights into the potential for pollinator‐mediated floral trait selection.  相似文献   
167.
BackgroundR-spondins, including R-spondin 1 (RSPO1), are a family of Wnt ligands that help to activate the canonical Wnt/β-catenin pathway, which is critical for intestinal epithelial cell proliferation and maintenance of intestinal stem cells. This proliferation underpins the epithelial expansion, or intestinal adaptation (IA), that occurs following massive bowel resection and short bowel syndrome (SBS). The purpose of this study was to identify if recombinant human RSPO1 (rhRSPO1) could be serially administered to SBS zebrafish to enhance cellular proliferation and IA.MethodsAdult male zebrafish were assigned to four groups: sham + PBS, SBS + PBS, sham + rhRSPO1, and SBS + rhRSPO1. Sham fish had a laparotomy alone. SBS fish had a laparotomy with distal intestinal ligation and creation of a proximal stoma. Fish were weighed at initial surgery and then weekly. rhRSPO1 was administered post-operatively following either a one- or two-week dosing schedule with either 3 or 5 intraperitoneal injections, respectively. Fish were harvested at 7 or 14 days with intestinal segments collected for analysis.ResultsRepeated intraperitoneal injection of rhRSPO1 was feasible and well tolerated. At 7 days, intestinal epithelial proliferation was increased by rhRSPO1. At 14 days, SBS + rhRSPO1 fish lost significantly less weight than SBS + PBS fish. Measurements of intestinal surface area were not increased by rhRSPO1 administration but immunofluorescent staining for β-catenin and gene expression for cyclin D1 was increased.ConclusionsIntraperitoneal injection of rhRSPO1 decreased weight loss in SBS zebrafish with increased β-catenin + cells and cyclin D1 expression at 14 days, indicating improved weight maintenance might result from increased activation of the canonical Wnt pathway.  相似文献   
168.
169.
The choice of treatment for primary nephrotic syndrome depends on the pathologic type of the disorder. Renal biopsy is necessary for a definitive diagnosis, but it is burdensome for the patients, and can be avoided if tests could be performed using urine or plasma. In this study, we analyzed 100 urinary proteins, 141 plasma proteins, and 57 urine/plasma ratios in cases of diabetic nephropathy (DN; n = 11), minimal change nephrotic syndrome (MCNS; n = 14), and membranous nephropathy (MN; n = 23). We found that the combination of urinary retinol-binding protein 4 and SH3 domain-binding glutamic acid-rich-like protein 3 could distinguish between MCNS and DN, with an area under the curve (AUC) of 0.9740. On the other hand, a selectivity index (SI) based on serotransferrin and immunoglobulin G, which is often used in clinical practice, distinguished them with an AUC of 0.9091. Similarly, the combination of urinary afamin and complement C3 urine/plasma ratio could distinguish between MN and DN with an AUC of 0.9842, while SI distinguished them with an AUC of 0.8538. Evidently, the candidates identified in this study were superior to the SI method. Thus, the aim was to test these biomarkers for accurate diagnosis and to greatly reduce the burden on patients.  相似文献   
170.
The ability to add or delete specific genes in swine will likely provide considerable benefits not just to agriculture but also to medicine, where pigs have potential as models for human disease and as organ donors. Here we have transferred nuclei from a genetically modified fibroblast cell line to porcine oocytes, matured in vitro under defined culture conditions, to create piglets expressing enhanced green fluorescent protein. The nuclear transfer-derived piglets were of normal size, although some mild symptoms of “large offspring syndrome” were evident. These experiments represent a next step towards creating swine with more useful genetic modifications.  相似文献   
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