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61.
Peter Sutovsky Mahmoud Aarabi Antonio Miranda-Vizuete Richard Oko 《Asian journal of andrology》2015,17(4):554-560
Biomarker-based sperm analysis elevates the treatment of human infertility and ameliorates reproductive performance in livestock. The negative biomarker-based approach focuses on proteins and ligands unique to defective spermatozoa, regardless of their morphological phenotype, lending itself to analysis by flow cytometry (FC). A prime example is the spermatid specific thioredoxin SPTRX3/TXNDC8, retained in the nuclear vacuoles and superfluous cytoplasm of defective human spermatozoa. Infertile couples with high semen SPTRX3 are less likely to conceive by assisted reproductive therapies (ART) and more prone to recurrent miscarriage while low SPTRX3 has been associated with multiple ART births. Ubiquitin, a small, proteolysis-promoting covalent posttranslational protein modifier is found on the surface of defective posttesticular spermatozoa and in the damaged protein aggregates, the aggresomes of spermiogenic origin. Semen ubiquitin content correlates negatively with fertility and conventional semen parameters, and with sperm binding of lectins LCA (Lens culinaris agglutinin; reveals altered sperm surface) and PNA (Arachis hypogaea/peanut agglutinin; reveals acrosomal malformation or damage). The Postacrosomal Sheath WWI Domain Binding Protein (PAWP), implicated in oocyte activation during fertilization, is ectopic or absent from defective human and animal spermatozoa. Consequently, FC-parameters of PAWP correlate with ART outcomes in infertile couples and with fertility in bulls. Assays based on the above biomarkers have been combined into multiplex FC semen screening protocols, and the surface expression of lectins and ubiquitin has been utilized to develop nanoparticle-based bull semen purification method validated by field artificial insemination trials. These advances go hand-in-hand with the innovation of FC-technology and genomics/proteomics-based biomarker discovery. 相似文献
62.
Pathological factors associated with survival benefit from adjuvant chemotherapy (ACT): a population‐based study of bladder cancer 下载免费PDF全文
63.
64.
《Anales de pediatría (Barcelona, Spain : 2003)》2014,80(1):22-31
ObjectiveThe present study evaluates energy and nutrient intake in Spanish children under three years of age, and compares the results with the current recommendations in order to identify possible inadequate nutrient intake.Patients and methodsA cross-sectional pilot study. The mothers completed a diet diary for four non-consecutive days, recording the products and amounts consumed by their children. Nutrient intake was calculated, and the results were compared with the dietary reference intakes (DRI) for each age group.ResultsA total of 188 children (93 boys and 95 girls) aged 0-6 (n = 41), 7-12 (n = 24), 13-24 (n = 57), and 25-36 months (n = 66) were included. Statistically significant differences in DRI were observed for most of the nutrients analyzed. Protein intake, in particular was 376% of DRI in children between 1-3 years of age. By age groups, 96% of the children aged 7-12 months, 88% of the children aged 13-24 months, and 97% of the children aged 25-36 months showed protein intakes more than two-fold DRI.ConclusionsNutrient intake differed from the DRI, particularly as regards proteins. A new study is required to determine whether the observed study deviations could be representative of the national population of this age group, as well as the possible effects on child health. 相似文献
65.
目的:制备含DiR碘化物荧光染料的长循环脂质体(DiR-SSL),采用SD大鼠和BALB/c裸鼠进行荧光成像的体内靶向性研究,利用空白SSL包封含5-羧基荧光素(5-FAM)的鳖甲肽(HGRFG-5-FAM,HF)制备HGRFG-5-FAM-SSL(HFL),研究HF及HFL分别给药于大鼠的药代动力学。方法:采用薄膜分散法制备DiR-SSL及HFL,取2组SD大鼠分别尾静脉注射HF及HFL,其HF质量浓度及剂量一致,于不同时间点采血,利用多功能微孔板检测仪分析HF血药浓度,计算药代动力学参数;将DiR-SSL尾静脉注射于BALB/c裸鼠,分别于1,2,5,7,24 h活体成像,读取荧光强度值;取正常SD大鼠尾静脉注射DiR-SSL,24 h后解剖心、肝、脾、肺、肾于荧光成像系统成像并读取荧光强度值,将肝组织冷冻切片进行激光共聚焦扫描。结果:HF注射到SD大鼠体内,其半衰期(T_(1/2))仅0.826 h,而HFL在相同剂量下,T1/2和药时曲线下面积(AUC_(0-∞))分别为HF的16.253,11.899倍;在BALB/c裸鼠活体成像中,荧光主要集中于肝脏位置,随着时间增加荧光强度逐渐减弱;SD大鼠各脏器中的DiR-SSL荧光在肝脏中最强,注射24 h后DiR-SSL仍能在肝脏储留。结论:SSL递药系统能显著延长HF在SD大鼠体内的T_(1/2)。SSL递药系统具有肝靶向作用,提示该系统可作为药物载体进行肝靶向递药。 相似文献
66.
Objectives
To investigate the role of SecA in protein secretion, and to evaluate the effect of biofilm formation on protein secretion in Streptococcus mutans.Design
S. mutans strains UA159 and GS-5 were used in this study. Cells grown in biofilm and planktonic conditions were observed using immunogold electron microscopy. The mRNA levels of ftf, gtfB, gtfC, gtfD, Pac and secA were analysed in different growth conditions using real-time quantitative polymerase chain reaction. The levels of wall proteins and whole-cell protein extracts were examined using Western blot analysis.Results
A microdomain colocalised with SecA and virulence factors such as Pac (AgI/II) and glucosyltransferase (GTF) was observed. The mRNA level of secA was upregulated in the biofilm condition. The level of protein expression of SecA and wall protein levels of GTF, fructosyltransferase (FTF) and Pac (AgI/II) in the biofilm condition were significantly higher than in the planktonic condition.Conclusions
These data suggest that S. mutans utilises the Sec pathway to secrete virulence factor proteins such as Pac (AgI/II), GTF and FTF, and protein secretion occurred at a distinct microdomain. The level of SecA, the key factor in the Sec pathway, was influenced significantly by biofilm formation in S. mutans. 相似文献67.
PTEN、p27在口腔粘膜白斑和口腔癌组织中的表达及意义 总被引:1,自引:0,他引:1
目的 探讨抑癌基因PTEN、p2 7在口腔粘膜白斑 (oralleukoplakia ,OLK)和口腔癌 (oralsquamouscellcancer,OSCC)组织中的蛋白表达及意义。方法 应用免疫组化S -P法检测 10例正常口腔粘膜、2 5例口腔粘膜白斑 (其中白斑伴上皮异常增生 15例 ,白斑不伴上皮异常增生 10例 )及 32例口腔癌组织中抑癌基因PTEN和p2 7的蛋白表达情况。结果 正常口腔粘膜和白斑不伴上皮异常增生组织中PTEN和 p2 7蛋白全部阳性表达 ;白斑伴上皮异常增生组织中PTEN和 p2 7蛋白阳性表达率分别为93.3%、73.3%。OSCC组织中PTEN蛋白阳性表达率为71.9% ,其中高、中、低分化OSCC组织中PTEN蛋白阳性表达率分别为 85 .7%、75 %和 33.3% ,统计学分析表明PTEN在OSCC组织中的蛋白表达与组织分化程度明显相关 (P <0 .0 5 )。OSCC组织中 p2 7蛋白的阳性表达率为4 0 .6 % ,其中高、中、低分化OSCC组织中p2 7蛋白的阳性表达率分别为 4 2 .9%、4 1.7%和 33.3% ,统计学分析表明p2 7在OSCC组织中的蛋白表达与组织分化程度无明显相关 (P >0 .0 5 )。结论 OSCC组织中PTEN和 p2 7蛋白的阴性表达率较高 ,说明PTEN和 p2 7基因突变或缺失在OSCC的发生发展过程中起重要作用。 相似文献
68.
Elverdin JC Chiarenza AP Luchelli MA Vatta M Bianciotti LG Boyer P Vacas MI 《Archives of oral biology》2006,51(8):621-628
Protein restriction impairs the salivary flow rate and composition in human and rats. The aim of the present work was to establish the effect of low protein (casein 5%) and protein free (casein 0%) isocaloric diets on sympathetic activity and salivary evoked secretion in the submandibular gland (SMG) of the rat. After 21 days, rats fed casein 0% presented: (a) a significant shift to the left of the dose-response curves (DRC) to the autonomic agonists-norepinephrine (NE), methoxamine, isoproterenol (ISO) and methacholine; (b) increased food consumption (p<0.001); (c) decreased body (p<0.001) and SMG (p<0.001) weights maintaining SMG/body (w/w) relation; (d) enhanced submandibular alpha1-adrenoceptor number without changes in the apparent dissociation constant (Kd); (e) increased submandibular NE content (p<0.05) and phosphoinositoside hydrolysis (p<0.001); (f) decreased submandibular tyrosine hydroxylase activity (TH) (p<0.01). Casein 5% feeding increased food consumption (p<0.01) and reduced body weight (p<0.05). This protein restriction increased metacholine-evoked salivation, but it altered neither submandibular sympathetic activity nor sympathetic-induced salivary secretion as compared to the Control group (C) fed a similar diet containing 25.5% protein. Present results suggest that in the adult rat, a protein free diet during 21 days lowers SMG sympathetic and cholinergic activity leading to supersensitivity as revealed by up-regulation of alpha1-adrenergic receptor number and increased autonomic-evoked salivation. 相似文献
69.
平阳霉素引发细胞凋亡与MAPK信号转导通路的关联性 总被引:6,自引:0,他引:6
目的 探讨平阳霉素引发细胞凋亡与分裂原激活的蛋白激酶家族(mitogen-activated protein kinase,MAPK)信号转导通路的关联性。方法 采用Western印迹法(western blot)检测分裂原激活蛋白激酶的表达。结果 平阳霉素作用KB细胞,随作用时间延长或药物浓度增加,磷酸化细胞外信号调节激酶的表达越不明显;而p-38MAPK蛋白激酶的表达无明显变化。结论 平阳霉素引发细胞凋亡与分裂原激活的蛋白激酶家族信号转导通路有关。 相似文献
70.
成人牙周炎治疗前后龈沟液蛋白质的电泳分析 总被引:1,自引:3,他引:1
目的通过分析成人牙周炎患者同一位点基础治疗前后1个月龈沟液(gingivalcrevicularfluid,GCF)中蛋白成分的改变,以期发现能够反映牙周健康及疾病状况的特异蛋白。方法采用滤纸条法收集12例成人牙周炎患者56个位点GCF样本,以十二烷基磺酸钠聚丙烯酰胺凝胶电泳(SDSPAGE)法分离,ImageMasterTM电泳图象分析仪分析其中的蛋白质。结果治疗后蛋白区带数及非血清源低分子量12000,10000蛋白的丰度及百分含量较治疗前显著减少(分别为P<0001和P<005),而38000蛋白百分含量呈增加趋势且与治疗前牙周探诊深度和GCF量呈负相关(P<005)。结论分子量为12000,10000的蛋白与牙周炎症有关;分子量38000的蛋白与疾病的好转有关 相似文献