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1.
2.
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   

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Cancer metastasis is one of the biggest challenges in cancer treatments since it increases the likelihood that a patient will die from the disease. Therefore, the availability of techniques for the early detection and quantification of tumors is very important. We have prepared cyanine 7.5 NHS ester (Cy7.5) and folic acid (FA) conjugated biodegradable mesoporous silica nanoparticles (bMSN@Cy7.5-FA NPs) (~100 nm) for visualizing tumors in vivo. The fluorescence spectra revealed that the emission peak of bMSN@Cy7.5-FA NPs had a red-shift of 1 nm. Confocal immunofluorescent images showed that bMSN@Cy7.5-FA NPs had an excellent targeting ability for visualizing cancer cells. In vivo fluorescence imaging has been conducted using an orthotopic model for pancreatic cancer within 48 h, and the fluorescence intensity reached a maximum at a post injection time-point of 12 h, which demonstrated that the use of bMSN@Cy7.5-FA NPs provides an excellent imaging platform for tumor precision therapy in mice.  相似文献   
5.
目的用FQ-RT-PCR技术检测外周血中hnRNPA2/B1表达水平及在肺癌诊断中的意义.方法用FQ-RT-PCR技术定量分别检测18例健康体检者、12例肺部良性疾病和30例肺癌患者外周血中hnRNPA2/B1 mRNA,并用β-actin对hnRNPA2/B1表达水平进行标化.结果 hnRNPA2/B1与β-actin的比值在正常对照组和良性肺部疾病组间差异无显著性(P>0.05),而肺癌组均高于前两组(P<0.05);hnRNPA2/B1基因在低分化鳞癌中的表达水平很低,与其它类型肺癌差异有显著性(P<0.05).结论 hnRNPA2/B1在血中表达水平的差异在肺癌诊断中具有一定临床应用价值,并与肺癌的病理分级有一定相关性.  相似文献   
6.

Objectives

We aimed to evaluate the relationship between baseline renal function and changes in telomere length in Han Chinese.

Methods

The telomere restriction fragment (TRF) length of leukocytes in the peripheral blood was measured in healthy volunteers recruited in 2014. The estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine (Scr) and serum cystatin C (CysC)-eGFRcys and eGFRScr-cys through the Cockcroft-Gault formula (eGFRC-G) or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI / eGFRCKD-EPI) equation. The correlation between telomere length changes over time and renal function was analyzed.

Results

Leukocyte TRF lengths were negatively correlated to age (r = -0.393, p < 0.001) and serum CysC (r = -0.180, p < 0.01), while positively associated with eGFRCKD-EPI, eGFRC-G, eGFRcys, and eGFRScr-cys (r = 0.182, 0.122, 0.290, and 0.254 respectively, p < 0.01). The 3-year change of telomere length was 46 bp/years. When adjusted for age, the associations between telomere length changes and baseline, subsequent TRF lengths, and serum CysC were no longer present. No association was observed between TRF length changes and renal function.

Conclusion

The rate of telomere length changes was affected by age and baseline telomere length. The telomere length changes might be important markers for aging.
  相似文献   
7.
舌大小与开He相关性的研究   总被引:6,自引:0,他引:6  
目的 研究舌大小与开He之间的关系。方法 采用B型超声成像方法分别测量正常He与开He患者的舌大小,通过牙He与正常He舌大小的比较,研究舌大小与开He的相关性。结果 开He患者的舌大小测量结果均值大于正常He者,而且这种差别有显著的统计学意义。结论 与正常He者比较,开He患者存在舌过大的特性。  相似文献   
8.
作者曾对238例口腔鳞癌术后应用中药“参阳”方的疗效进行前瞻性的研究,本文继续对已生存4~8年的56例病员门诊随访结果进行分析.结果是生存情况:7年生存期原治疗组高于原对照组12.5%,原治疗组30例均健在,而原对照组中的26例,2例带瘤生存,1例死亡;T细胞亚群测定中,复发死亡者的CD8值均升高,CD4/CD8比值均下降;中医辨证中,正常者及肾气虚者的例数以治疗组为多,而阴虚与气阴两虚者,治疗组低于对照组;由上提示:经“参阳”方治疗者有较好的远期疗效.  相似文献   
9.
以藻酸钙为载体的可注射性组织工程骨研究   总被引:8,自引:0,他引:8  
目的:研究藻酸钙/骨髓基质成骨细胞复合物在有免疫动物体内成骨的可行性。方法:从免筋骨中获取骨髓基质成骨细胞,将骨髓基质成骨细胞与25g/L藻酸钠溶胶混合形成藻酸钠/骨髓基质成骨细胞复合物,取其2ml与0.17g硫酸钙粉末混合均匀,注射于新西兰兔背部皮下,观察成骨情况。结果:藻酸钙/骨髓基质成骨细胞复合物植入免皮下四周后有类软骨样组织形成,8周时有骨小梁、骨髓腔等骨组织结构。结论:藻酸钙/骨髓基质成骨细胞复合物通过注射方式在有免疫动物体内可以形成骨组织。  相似文献   
10.
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