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111.
High bone morphogenetic protein-15 level in follicular fluid is associated with high quality oocyte and subsequent embryonic development 总被引:2,自引:0,他引:2
Wu YT Tang L Cai J Lu XE Xu J Zhu XM Luo Q Huang HF 《Human reproduction (Oxford, England)》2007,22(6):1526-1531
BACKGROUND: Bone morphogenetic protein-15 (BMP-15) has been shown to influence oocyte maturation and quality. However, no relationship has been established between BMP-15 and oocyte quality/embryonic development in humans. The aim of this study is to investigate BMP-15 level in human follicular fluid (FF) and its possible role in determining oocyte quality and developmental potential. METHODS: A total of 79 oocytes and their corresponding FF from 79 women undergoing ICSI were examined. Individual oocytes were inseminated and subsequently assessed on the basis of their fertilization, cleavage and preimplantation development. BMP-15, FSH, estradiol (E(2)) and progesterone levels of FF were also analysed via the techniques of western blot or radioimmunoassay. RESULTS: Higher FF BMP-15 levels were observed in the fertilized and cleaved groups versus the unfertilized and uncleaved groups, respectively (P < 0.05). The best (Grade I) embryo morphology was associated with higher FF BMP-15 levels than Grade II or III embryos (P < 0.01). A significant positive correlation was found between BMP-15 and E(2) levels in the same follicle. CONCLUSION: The present study demonstrates that the BMP-15 level in FF appears to be a potential factor in predicting oocyte quality and subsequent embryo development, and is correlated with E(2) level, which may additionally be a valuable predictor of oocyte fertilization. 相似文献
112.
Fawad Ur Rehman Tianyu Du Sana Shaikh Xuerui Jiang Yun Chen Xiaoqi Li Huan Yi Jiang Hui Baoan Chen Matthias Selke Xuemei Wang 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(8):2619-2631
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al. 相似文献
113.
目的:构建小鼠原始生殖细胞(PGCs)报告基因系统。方法:根据CRISPR基因编辑技术结合同源重组原理,针对鼠Prdm1和Dppa3基因的翻译起始位点ATG附近位置分别设计一对sgRNA,并根据Cas9切割位点以及拟插入目的片段构建相应的用于同源重组的供体质粒,将sgRNA与Donor质粒同时转染入小鼠胚胎干细胞(ESCs)中,并利用质粒携带的抗性基因筛选出目标单克隆细胞,并进行基因型鉴定。结果:通过提取单克隆细胞的基因组DNA进行基因型鉴定,PCR和Sanger测序结果显示,单克隆细胞的基因组中,Prdm1和Dppa3基因翻译起始位点后分别成功插入eGFP和mCherry荧光蛋白编码序列。利用细胞因子诱导eGFP-Prdm1/mCherry-Dppa3mESCs(mouse ESCs)定向分化为mPGCs(mouse PGCs),流式细胞仪检测显示诱导分化的mPGCs特异表达eGFP和mCherry荧光信号。结论:成功构建mPGCs报告基因系统,可用于后续研究mPGCs命运决定的分子机制,对于研究小鼠早期胚胎发育过程具有重要意义。 相似文献
114.
目的 探讨溴隐亭对斑马鱼胚胎生存率、孵化时间和形态发育异常的影响。方法 取斑马鱼胚胎随机分成溴隐亭溶液组(10 μmol/L组、20 μmol/L组、50 μmol/L组、100 μmol/L组),control组(空白对照组)和0.5%二甲基亚砜(DMSO)对照组,比较各组胚胎生存率、孵化时间、幼鱼鱼鳔充气、幼鱼畸形及发育异常情况。结果 48 受精后发育小时数(HPF)时,溴隐亭溶液组胚胎孵化率低于2个对照组(P<0.05);120 HPF时,20 μmol/L组、50 μmol/L组、100 μmol/L组斑马鱼幼鱼鱼鳔充气率、水肿率分别低于、高于其余组(P<0.05),但各组畸形率比较,差异无统计学意义(P>0.05);144 HPF时,50 μmol/L组、100 μmol/L组较其余4组斑马鱼幼鱼生存率降低(P<0.05)。结论 高浓度溴隐亭可引起斑马鱼胚胎孵化延迟、斑马鱼幼鱼生存率降低、水肿及鱼鳔充气障碍,但对斑马鱼胚胎发育畸形则无影响。 [国际神经病学神经外科学杂志, 2022, 49(3): 8-13.] 相似文献
115.
视网膜变性疾病导致视力下降,是视网膜色素上皮(RPE)细胞或感光细胞引起不可逆性损害或凋亡所造成的功能异常,从而导致的致盲性眼病,常引起视觉障碍甚至失明。人胚胎干细胞(hESCs)是一种能够多向分化的细胞。凭借适当的方法,hESCs可分化为各种视网膜细胞。由于人体RPE细胞无法再生,研究表明运用干细胞源性RPE细胞移植治疗视网膜病变的临床治疗方法具有实用前景,且近年来已取得突破性进展。多因素的限制、方法的选择以及诱导条件的复杂等使诱导分化RPE的效率和移植后存活率存在较大差异且不稳定,所以现阶段研究重点在于如何综合不同培养方法,取其利去其弊,提高hESCs定向分化效率以及细胞数量与质量,降低培养污染以及免疫排斥反应等。本文将对目前存在多种培养方法进行举例归纳总结,针对不同角度作出综述。 相似文献
116.
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118.
Julie K. Klint Géza Berecki Thomas Durek Mehdi Mobli Oliver Knapp Glenn F. King David J. Adams Paul F. Alewood Lachlan D. Rash 《Biochemical pharmacology》2014
Spider venoms are replete with peptidic ion channel modulators, often with novel subtype selectivity, making them a rich source of pharmacological tools and drug leads. In a search for subtype-selective blockers of voltage-gated calcium (CaV) channels, we isolated and characterized a novel 39-residue peptide, ω-TRTX-Cc1a (Cc1a), from the venom of the tarantula Citharischius crawshayi (now Pelinobius muticus). Cc1a is 67% identical to the spider toxin ω-TRTX-Hg1a, an inhibitor of CaV2.3 channels. We assembled Cc1a using a combination of Boc solid-phase peptide synthesis and native chemical ligation. Oxidative folding yielded two stable, slowly interconverting isomers. Cc1a preferentially inhibited Ba2+ currents (IBa) mediated by L-type (CaV1.2 and CaV1.3) CaV channels heterologously expressed in Xenopus oocytes, with half-maximal inhibitory concentration (IC50) values of 825 nM and 2.24 μM, respectively. In rat dorsal root ganglion neurons, Cc1a inhibited IBa mediated by high voltage-activated CaV channels but did not affect low voltage-activated T-type CaV channels. Cc1a exhibited weak activity at NaV1.5 and NaV1.7 voltage-gated sodium (NaV) channels stably expressed in mammalian HEK or CHO cells, respectively. Experiments with modified Cc1a peptides, truncated at the N-terminus (ΔG1–E5) or C-terminus (ΔW35–V39), demonstrated that the N- and C-termini are important for voltage-gated ion channel modulation. We conclude that Cc1a represents a novel pharmacological tool for probing the structure and function of L-type CaV channels. 相似文献
119.
目的观察恩替卡韦联合复方牛胎肝提取物片治疗慢性乙型肝炎肝纤维化的效果。方法将82例患者随机分为对照组41例及治疗组41例,对照组给予恩替卡韦治疗48周,治疗组在对照组基础上加用复方牛胎肝提取物片治疗48周,检测肝功能指标、肝纤维化指标,并在治疗前后进行肝活检。结果治疗48周后,治疗组的血清白蛋白、肝纤维化指标、肝纤维化程度与对照组比较差异均有统计学意义(P〈0.05)。结论恩替卡韦联合复方牛胎肝提取物片治疗肝纤维化有较好的效果,两者联合可能在抗纤维化方面有一定的协同作用。 相似文献
120.
A temporary confinement of the quaternary tetramethylammonium tetrafluoroborate (TMA BF4) salt among polyamide molecules has been used for the preparation of aliphatic polyamide nylon 6,6 fibres with high-modulus and high-strength properties. In this method, the suppression or the weakening of the hydrogen bonds between the nylon 6,6 segments has been applied during the conventional low-speed melt spinning process. Thereafter, after the complete hot-drawing stage, the quaternary ammonium salt is fully extracted from the drawn 3 wt.% salt-confined fibres and the nascent fibres are, subsequently, thermally stabilized. The structural developments that are acquired in the confined-nylon 6,6 fibres are ascribed to the developments of the overall fibres’ properties due to the confinement process. Surprisingly, unlike the neat nylon 6,6 fibres, the X-ray diffraction (XRD) patterns of the as-spun salt-confined fibres have shown diminishing of the (110)/(010) diffraction plane that obtained pseudohexagonal-like β’ structural phase. Moreover, the β’ pseudohexagonal-like to α triclinic phase transitions took-place due to the hot-drawing stage (draw-induced phase transitions). Interestingly, the hot-drawing of the as-spun salt-confined nylon 6,6 fibres achieved the same maximum draw ratio of 5.5 at all of the drawing temperatures of 120, 140 and 160 °C. The developments that happened produced the improved values of 43.32 cN/dtex for the tensile-modulus and 6.99 cN/dtex for the tensile-strength of the reverted fibres. The influences of the TMA BF4 salt on the structural developments of the crystal orientations, on the morphological structures and on the improvements of the tensile properties of the nylon 6,6 fibres have been intensively studied. 相似文献