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Producing meiosis‐competent germ cells (GCs) from embryonic stem cells (ESCs) is essential for developing advanced therapies for infertility. Here, a novel approach is presented for generation of GCs from ESCs. In this regard, microparticles (MPs) have been developed from alginate sulfate loaded with bone morphogenetic protein 4 (BMP4). The results here show that BMP4 release from alginate sulfate MPs is significantly retarded by the sulfated groups compared to neat alginate. Then, BMP4‐laden MPs are incorporated within the aggregates during differentiation of GCs from ESCs. It is observed that BMP4‐laden MPs increase GC differentiation from ESCs at least twofold compared to the conventional soluble delivery method. Interestingly, following meiosis induction, Dazl , an intrinsic factor that enables GCs to enter meiosis, and two essential meiosis genes (Stra8 and Smc1b ) are upregulated significantly in MP‐induced aggregates compared to aggregates, which are formed by the conventional method. Together, these data show that controlled delivery of BMP4 during ESC differentiation into GC establish meiosis‐competent GCs which can serve as an attractive GC source for reproductive medicine.

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李克  商学军  陈永刚 《色谱》2004,22(4):412-415
采用高效液相色谱法测定精浆中过氧化脂质(lipid peroxidation,LPO)含量,研究了有正常生育能力的男子和不育症患者精浆中LPO含量水平差异及其对男子不育症的影响。精浆样品经酸化后,分解生成的丙二醛(malondialdehyde,MDA)与硫代巴比妥酸(thiobarbituric acid,TBA)缩合反应形成紫红色产物,以Lichrospher C18化学键合硅胶为固定相,0.025 mol/L KH2PO4 (pH 6.2)-甲醇(体积比为58∶42)为流动相进行色谱等度分离  相似文献   
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Male factor infertility is involved in almost half of all infertile couples. Lack of the ejaculated sperm owing to testicular malfunction has been reported in 6–10% of infertile men, a condition named nonobstructive azoospermia (NOA). In this study, we investigated untargeted metabolomic profiling of the seminal plasma in NOA men using gas chromatography–mass spectrometry and advance chemometrics. In this regard, the seminal plasma fluids of 11 NOA men with TESE‐negative, nine NOA men with TESE‐positive and 10 fertile healthy men (as a control group) were collected. Quadratic discriminate analysis (QDA) technique was implemented on total ion chromatograms (TICs) for identification of discriminatory retention times. We developed multivariate classification models using the QDA technique. Our results revealed that the developed QDA models could predict the classes of samples using their TIC data. The receiver operating characteristic curves for these models were >0.88. After recognition of discriminatory retention time's asymmetric penalized least square, evolving factor analysis, correlation optimized warping and alternating least squares strategies were applied for preprocessing and deconvolution of the overlapped chromatographic peaks. We could identify 36 discriminatory metabolites. These metabolites may be considered discriminatory biomarkers for different groups in NOA.  相似文献   
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Background: Type-one diabetes (T1D), a chronic autoimmune disease with marked inflammatory responses, is associated with infertility complications and implications. Based on the anti-diabetic, antioxidant, and anti-hyperlipidemic potential of Portulaca oleracea (PO), this study aimed to evaluate the protective effect of this plant extract on streptozotocin-induced type-I-diabetes-associated reproductive system dysfunction and inflammation. Methods: Male rats were randomly divided into four experimental groups: control, diabetic, and treatment/s (PO extract at 100 or 300 mg/kg/daily). Then food and water consumption, body, testis and epididymis weights, histopathological evaluation, seminiferous tubules diameter, sperm count and motility, glucose levels, sex hormones, and inflammatory and oxidative stress markers were evaluated. Results: Our results showed that streptozotocin-induced diabetes significantly increased food and water consumption; increased glucose, MDA, TGF-β1, and TNF-α levels; and decreased the seminiferous tubules diameter, sperm count and motility, levels of LH, testosterone, total thiol, VEGF, and SOD activity. Interestingly, PO extract (phytochemically characterized by using liquid chromatography–mass spectrometry to detect bioactive molecules) significantly ameliorated these parameters and histopathological indexes’ damage in rats. Conclusion. Even if more preclinical assessments are needed to better characterize the mechanism/s of action, the results of this study will pave the way for the rational use of PO on diabetic-associated clinical complications and implications.  相似文献   
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男性不育患者精浆锌含量的分析   总被引:2,自引:0,他引:2  
为探讨锌与男性不育患者的关系 ,本文研究测定了 173例男性不育患者精浆锌的含量 ,同时与正常生育男性进行比较。结果显示 ,正常生育男性与不育男性中少精子症、精子活率 <55%、活动力Ⅲ、Ⅳ级 <2 5% ,梗阻性无精子症 ,精液白细胞≥ 10 6 mL之间均有显著性差异。说明锌对男性生育过程起相当重要的作用 ,它在精浆中含量的变化可能是导致男性不育的原因之一。  相似文献   
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A high-performance liquid chromatographic (HPLC) method for the analysis of coenzyme Q10 (CoQ10) in human seminal plasma was developed and applied to investigate its clinical significance as a reference index relating to oxidative stress and infertile status of spermatozoa. After precipitation of proteins in seminal plasma with methanol, CoQ10 and coenzyme Q9 (CoQ9; internal standard) were extracted with hexane. The supernatant after centrifugation was evaporated to dryness with nitrogen at 45 degrees C. The residue was re-dissolved in isopropanol. HPLC separation of the sample solution was performed on a Lichrospher C(18) column with a mobile phase composed of isopropanol-methanol-tetrahydrofuran in the ratio of 55:39:6 (v/v/v) at a flow rate of 1.0 mL/min. Under the chromatographic conditions described, the CoQ10 and CoQ9 had retention times of approximately 5.83 and 4.97 min, respectively. The peaks were detected at UV 275 nm. Good separation and detectability of CoQ10 in human seminal plasma were obtained. The method was linear in the range 0.01-10.00 microg/mL. The relative standard deviations within- and between-assay for CoQ10 analysis were 0.85 and 1.86%, respectively. The average recoveries were 94.1-99.0% for the human seminal plasma samples. The CoQ10 levels in seminal plasma of 195 patients and 23 control subjects were studied. CoQ10 concentrations in the two populations were: 37.1 +/- 12.2 ng/mL in the fertile group and 48.5 +/- 20.4 ng/mL in the infertile group. The large difference (p < 0.01) between the fertile and infertile populations is evident.  相似文献   
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An aromatase encoded by the CYP19 gene catalyzes the final step in the biosynthesis of estrogens, which is related to endometriosis development. To assess the association of CYP19 gene polymorphisms with the risks of endometriosis, chocolate cysts and endometriosis-related infertility, a case–control study was conducted in Chinese Han women by recruiting 225 healthy control females, 146 patients with endometriosis, 94 endometriosis women with chocolate cyst and 65 women with infertility resulting from endometriosis, as diagnosed by both pathological and laparoscopic findings. Individual genotypes at rs2236722:T>C, rs700518:A>G, rs10046:T>C and [TTTA]n polymorphisms were identified. Allelic and genotypic frequencies were compared between the control group and case groups by chi-square analysis. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were determined by logistic regression analysis to predict the association of CYP19 gene polymorphisms with the risk of endometriosis, the related chocolate cysts and infertility. The genotype distributions of the tested CYP19 gene polymorphisms were not significantly different between the healthy control group and the endometriosis/endometriosis with the chocolate cyst group. However, the CYP19 rs700518AA genotype was significantly associated with an increased risk of endometriosis-related infertility (55.4% in the infertility group vs 25.3% in the control group, P<0.001; OR (95% CI): 3.66 (2.06–6.50)) under the recessive form of the A allele. Therefore, we concluded that in Chinese Han females CYP19 gene polymorphisms are not associated with susceptibility to endometriosis or chocolate cysts, whereas CYP19 rs700518AA genotype confers genetic susceptibility to endometriosis-related infertility.  相似文献   
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目的就针灸治疗多囊卵巢综合征致不孕症的临床疗效进行观察与探究。方法选择广州市天河区冼村街社区卫生服务中心自2013年4月至2015年5月期间收治的多囊卵巢综合征致不孕症患者66例,依据患者来院先后顺序平均分为参照组和观察组,每组患者33例。参照组患者予以常规治疗,观察组患者采用针灸治疗,最后比对两组患者的临床治疗效果。结果经不同方法治疗后,观察组患者各项指标的改善程度好于参照组,妊娠率和排卵率也均高于参照组,组间统计后差异显著。结论在多囊卵巢综合致不孕症患者治疗中应用针灸,其临床效果显著,具有临床应用价值。  相似文献   
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In the past decade, mRNA markers have been well demonstrated as promising molecular markers in forensic body fluid identification (BFI), and successfully used in wide applications. Several studies have assessed the performance of semen-specific mRNA markers in distinguishing semen from other common body fluids at the crime scene. Infertility has been reported as a global health problem that is affecting approximately 15% of couples worldwide. Therefore, it is important for forensic researchers to consider the impact of infertility on semen identification. This study aimed to explore the effect of semen from infertile men (hereinafter “infertile semen”) on BFI and to identify semen-specific mRNAs that can efficiently and accurately distinguish normal and infertile semen samples from other body fluids. Results showed that the selected five mRNAs (KLK3, TGM4, SEMG1, PRM1, and PRM2) performed a significantly high semen specificity in normal semen. Moreover, KLK3 was slightly influenced by infertile semen samples with over 98% positive results in all semen samples. The accuracy to predict normal semen reached up to 96.6% using the discrimination function Y1 with KLK3 and PRM1. However, when the infertile semen samples were included in discrimination function (function Y2 with KLK3), the accuracy rate of semen identification (including the normal and infertile semen) was down to 89.5%. Besides, the sensitivity of multiplex assay could reach down to 50pg. Our results suggest that it is important to consider the presence of infertile semen when using mRNAs to identify semen samples, which would have a far-reaching impact in forensic identification.  相似文献   
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