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71.
72.
目的 总结貌似多发性硬化的皮层下梗死和白质脑病的常染色体显性遗传性脑动脉病(CADASIL)的临床特点.方法 报告1例经基因检查和周围神经活检确诊为CADASIL的临床资料.结果 患者腓肠神经活检可见有髓神经纤维密度轻度减少,电镜下可见神经束膜小动脉中层平滑肌细胞外大量颗粒性电子致密嗜锇颗粒物质(GOM)沉积.基因检测显示Notch3基因4号外显子Cys117Arg突变.结论 为避免CADASIL的漏诊及误诊,凡遇青年反复脑卒中发作,又无高血压、糖尿病等常见的血管病危险因素,虽无偏头痛病史,亦应注意追问家族史并做基因检测和周围神经活检. 相似文献
73.
目的 通过测定大鼠局灶性脑缺血-再灌流后不同时点脑组织中髓过氧化物酶(MPO)和神经元特异性烯醇化酶(NSE)活性的变化,探讨炎症反应与脑缺血损伤的关系.方法 用线栓法制备大鼠左侧大脑中动脉缺血-再灌流模型,检测缺血3h再灌流后6h、12h、24h、48h、72h和7d脑组织中MPO和NSE活性、脑梗死体积的变化.结果 缺血组脑组织中NSE和MPO活性升高,再灌流后48h的NSE为(5.44±0.95)ng/ml,MPO为4.49±0.22;72h分别为(5.36±0.65)ng/l和5.96±0.19,升高最为明显.脑梗死体积随再灌流时间延长而增加,第7d梗死体积百分比为(39.18±0.63)%.局灶性缺血脑组织中MPO活性与组织损伤(NSE活性)间具有高度正相关性.结论 炎症反应是加重脑缺血损伤的重要因素. 相似文献
74.
Diethylstilbestrol impaired oogenesis of yellow catfish juveniles through disrupting hypothalamic–pituitary–gonadal axis and germ cell development 下载免费PDF全文
Yaqin Wang Yingwen Li Qiliang Chen Zhihao Liu 《Journal of applied toxicology : JAT》2018,38(3):308-317
Diethylstilbestrol (DES), a non‐steroidal estrogen, has been found to cause altered germ cell development and disordered ovarian development in fish females. However, the mechanisms that might be involved are poorly understood. In this study, female juveniles of yellow catfish (Pelteobagrus fulvidraco) (120 days post‐hatching) were exposed to two doses (10 and 100 ng l?1) of DES for 28 days. After the endpoint of exposure, decreased ovary weight and gonadosomatic index, as well as various ovarian impairments were observed in response to DES. Besides, DES elevated the mRNA levels of vitellogenin 1 (vtg 1) and estrogen receptor 1 (esr 1) in liver and decreased 17β‐estradiol level in plasma. Correspondingly, suppressed mRNA levels of the key genes in the hypothalamic–pituitary–gonadal axis (such as cyp19a1b, gnrh‐II, fshβ and lhβ in brain and fshr, lhr and cyp19a1a in ovary) after DES exposure were also observed. The declined level of plasma 17β‐estradiol and altered gene expressions of genes in the hypothalamic–pituitary–gonadal axis were thus supposed to be closely related to the disrupted oogenesis in DES‐treated fish. Analyses further demonstrated that, higher concentration of DES elevated the expression ratio of bax/bcl‐2, indicating the enhanced apoptosis occurred in ovary. Moreover, DES upregulated the expressions of genes involved in proliferation (cyclin d1 and pcna), meiotic entry (cyp26a1 and scp3) and meiotic maintenance (dmc1), resulting in arrested oogenesis in catfish. The present study greatly extended our understanding on the mechanisms underlying of reproductive toxicity of DES on fish oogenesis. 相似文献
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Jin-Lan Zhang Xiao-Hui Huang Hong-Yang Chang Yi Zheng Xue Cao 《Systems biology in reproductive medicine》2018,64(4):266-273
The objective of this study was to explore the association of sperm mitochondrial ND2 (MT-ND2) gene variants with total fertilization failure (TFF). A retrospective comparative study of 246 cases of fresh in vitro fertilization (IVF) cycles or half-intracytoplasmic sperm injection cycles in the Han Chinese population was performed from July 2011 to May 2017. A total of 59 cases undergoing TFF, and 187 control cases with normal fertilization (fertilization rates >50%) were included. The sperm mitochondrial genovariation was determined using nested sequencing. A total of 32 homoplasmic variants and 47 heteroplasmic variants of MT-ND2 gene were observed in this study. There were no significant differences in the frequencies of the 32 homoplasmic variants of MT-ND2 gene between the TFF and control groups. A total of 53 pair-wise comparisons were performed, and the general characteristics of the IVF failure and control subjects were adjusted in logistic models. Data suggested that there were no significant differences in the frequencies of point 4914, 5320, and 5426 heteroplasmic variants of MT-ND2 gene between the TFF and control groups. In addition, no significant difference was observed in the frequency of mtDNA haplogroup D or haplogroup G between the IVF failure group and the normal fertilization group. This study suggests that the MT-ND2 gene variants might not be associated with TFF.
Abbreviations: ATP: adenosine triphosphate; dNTP: deoxy-ribonucleoside triphosphate; FADH2: flavin adenine dinucleotide; FDR: false discovery rate; FSH: follicle-stimulating hormone; IVF: in vitro fertilization; LH: luteinizing hormone; MTATP6: mitochondrially encoded ATP synthase 6; MTCYB: mitochondrially encoded cytochrome b; mtDNA: mitochondrial DNA; MT-ND2: mitochondrial ND2; NADH: nicotinamide adenine dinucleotide; ND2: NADH dehydrogenase subunit 2; OXPHOS: oxidative phosphorylation; PCR: single nucleotide polymorphisms; SNPs: single nucleotide polymorphisms; TFF: total fertilization failure 相似文献
79.
Qian Zhang Yunmei Song Stephen W. Page Sanjay Garg 《Journal of pharmaceutical sciences》2018,107(2):587-594
The transdermal delivery of 2 fluorescent probes with similar molecular weight but different lipophilicity, into and through the skin from 2 commercially available transdermal bases, pluronic lecithin organogel, and Lipoderm® has been evaluated. First, in vitro penetration of fluorescein sodium and fluorescein (free acid) through porcine skin was evaluated. Retention and depth distribution profiles in skin were obtained by tape stripping and then followed by optical sectioning using multiphoton microscopy. The results showed that Lipoderm® led to an enhanced penetration of the hydrophilic compound, fluorescein sodium. For the lipophilic compound fluorescein (free acid), Lipoderm® performed similar to pluronic lecithin organogel base, where minimal drug was detected in either receptor phase. The skin retention and depth distribution results also showed that the hydrophilic fluorescein sodium had high skin retention with Lipoderm®, whereas fluorescein (free acid) had very low penetration and retention with increasing skin depth. Moreover, optical sectioning by multiphoton microscopy revealed an uneven distribution of probes across the skin in the x-y plane for both transdermal bases. This work showed that a hydrophilic compound has significantly increased skin penetration and retention when formulated with Lipoderm®, and the skin retention of the probe was the main determinant of its skin flux. 相似文献
80.
In clinical therapy, the poor prognosis of hepatocellular carcinoma (HCC) is mainly attributed to the failure of chemotherapeutical agents to accumulate in tumor as well as lack of potency of tumor penetration. In this work, we developed actively tumor-targeting micelles with pH-sensitive linker as a novel nanocarrier for HCC therapy. These micelles comprised biodegradable poly(ethylene glycol)-poly(aspartate) polymers, in which paclitaxel can be covalently conjugated to pAsp via an acid-labile acetal bond to form pH-responsive structures. In vitro drug release studies showed that these structures were stable in physiological condition, whereas collapsed once internalized into cells due to the mildly acidic environment in endo/lysosomes, resulting in facilitated intracellular paclitaxel release. In addition, dehydroascorbic acid and guanidinopropyl methacrylamide polymers were decorated on the surface of micelles to achieve specific tumor accumulation and tumor penetration. Cellular uptake and in vivo imaging studies proved that these micelles had remarkable targeting property toward hepatocarcinoma cells and tumor. Enhanced anti-HCC efficacy of the micelles was also confirmed both in vitro and in vivo. Therefore, this micellar system may be a potential platform of chemotherapeutics delivery for HCC therapy. 相似文献