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991.
Valdeci Carlos Dionisio Mônica de Biagi Curtarelli Luciane Aparecida Pascucci Sande de Souza 《Journal of electromyography and kinesiology》2013,23(4):948-957
The aim of the present study was to compare kinetic, kinematic, and electromyographic variables during the sitting movement between healthy elderly and in those with Parkinson’s disease (PD) with moderate involvement. We hypothesized that subjects with PD would show difficulty in selecting the muscles for the task and that this could be related to the co-activation pattern and would be reflected in the behavior of some biomechanical variables. Fifteen subjects participated in this study, seven healthy subjects (NN group) and eight with Parkinson’s disease. Electromyography (EMG) activity of the tibialis anterior (TA), soleus (SO), vastus medialis oblique (VMO), biceps femoris (BF), and erector spinae (ES) were recorded, and biomechanical variables were calculated, during four phases of the sitting movement. Compared to healthy subjects, the subjects with PD showed more flexion at the ankle, knee, and hip joints in the initial position and lower joint velocity. However, the EMG activity and hip, knee, and ankle joint torques were not different during all phases of movement. The sitting movement in PD subjects with moderate involvement generates EMG activity and joint torques similar to healthy elderly subjects. Only a reduced movement velocity was found in PD patients during the sitting task. 相似文献
992.
为构建西方马脑炎病毒(western equine encephalomyelitis virus,WEEV)结构基因C-E3-E2-6k-E1重组真核表达载体,并研究其作为核酸疫苗的免疫原性.采用PCR方法扩增目的基因,酶切之后连接到pcDNA3.1上构建真核表达载体pcDNA3.1-C-E,用酶切和测序分析方法鉴定正确后,重组质粒被转染到293T细胞,经电镜检测和间接免疫荧光方法证明基因可以表达后,用该重组质粒免疫小鼠,免疫后检测实验组小鼠外周血中CD4+T细胞/CD8+T细胞比例和血清中细胞因子IL-2、IL-4及IFN-γ浓度,以上实验组各项免疫指标与对照组相比差异均显著(P< 0.05);ELISA方法检测实验组小鼠血清中WEEV的IgG抗体效价是1∶16.研究结果表明重组质粒pcDNA3.1-C-E可在细胞中获得瞬时表达,并且重组质粒作为核酸疫苗能够刺激小鼠产生免疫反应,具有较强免疫原性,为今后WEEV核酸疫苗研制奠定了良好基础. 相似文献
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996.
目的:应用蛋白芯片法与欧蒙斑点法检测血清抗核抗体,并对其结果进行比较分析。方法:收集95例血清样本,其中45例确诊为自身免疫性疾病,阴性50例,同时采用蛋白芯片法和欧盟斑点法检测其抗核抗体(SSA、SSB、Sm、RNP、Scl—70、Jo-1、CENPB),并对结果进行对比分析。结果:45例确诊病例中,蛋白芯片法阳性44份,欧蒙斑点法阳性41份,敏感度分别为97.78%和91.11%,特异度分别为98.95%和95.79%;按卡方检验进行结果统计,x^2=1.75,P〉0.05,差异无统计学意义。结论:蛋白芯片可用于临床检测自身免疫性疾病、治疗监测、疗效评估和预后判断。 相似文献
997.
《Critical reviews in biochemistry and molecular biology》2013,48(5):376-385
The lipotoxic effects of obesity are important contributing factors in cancer, diabetes, and cardiovascular disease (CVD), but the genetic mechanisms, by which lipotoxicity influences the initiation and progression of CVD are poorly understood. Hearts, of obese and diabetic individuals, exhibit several phenotypes in common, including ventricular remodeling, prolonged QT intervals, enhanced frequency of diastolic and/or systolic dysfunction, and decreased fractional shortening. High systemic lipid concentrations are thought to be the leading cause of lipid-related CVD in obese or diabetic individuals. However, an alternative possibility is that obesity leads to cardiac-specific steatosis, in which lipids and their metabolites accumulate within the myocardial cells themselves and thereby disrupt normal cardiovascular function. Drosophila has recently emerged as an excellent model to study the fundamental genetic mechanisms of metabolic control, as well as their relationship to heart function. Two recent studies of genetic and diet-induced cardiac lipotoxicity illustrate this. One study found that alterations in genes associated with membrane phospholipid metabolism may play a role in the abnormal lipid accumulation associated with cardiomyopathies. The second study showed that Drosophila fed a diet high in saturated fats, developed obesity, dysregulated insulin and glucose homeostasis, and severe cardiac dysfunction. Here, we review the current understanding of the mechanisms that contribute to the detrimental effects of dysregulated lipid metabolism on cardiovascular function. We also discuss how the Drosophila model could help elucidate the basic genetic mechanisms of lipotoxicity- and metabolic syndrome-related cardiomyopathies in mammals. 相似文献
998.
《Critical reviews in biochemistry and molecular biology》2013,48(5):375-430
AbstractDespite the rapid mutational change that is typical of positive-strand RNA viruses, enzymes mediating the replication and expression of virus genomes contain arrays of conserved sequence motifs. Proteins with such motifs include RNA-dependent RNA polymerase, putative RNA helicase, chymotrypsin-like and papain-like proteases, and methyltransferases. The genes for these proteins form partially conserved modules in large subsets of viruses. A concept of the virus genome as a relatively evolutionarily stable “core” of housekeeping genes accompanied by a much more flexible “shell” consisting mostly of genes coding for virion components and various accessory proteins is discussed. Shuffling of the “shell” genes including genome reorganization and recombination between remote groups of viruses is considered to be one of the major factors of virus evolution.Multiple alignments for the conserved viral proteins were constructed and used to generate the respective phylogenetic trees. Based primarily on the tentative phylogeny for the RNA-dependent RNA polymerase, which is the only universally conserved protein of positive-strand RNA viruses, three large classes of viruses, each consisting of distinct smaller divisions, were delineated. A strong correlation was observed between this grouping and the tentative phylogenies for the other conserved proteins as well as the arrangement of genes encoding these proteins in the virus genome. A comparable correlation with the polymerase phylogeny was not found for genes encoding virion components or for genome expression strategies. It is surmised that several types of arrangement of the “shell” genes as well as basic mechanisms of expression could have evolved independently in different evolutionary lineages.The grouping revealed by phylogenetic analysis may provide the basis for revision of virus classification, and phylogenetic taxonomy of positive-strand RNA viruses is outlined. Some of the phylogenetically derived divisions of positive-strand RNA viruses also include double-stranded RNA viruses, indicating that in certain cases the type of genome nucleic acid may not be a reliable taxonomic criterion for viruses.Hypothetical evolutionary scenarios for positive-strand RNA viruses are proposed. It is hypothesized that all positive-strand RNA viruses and some related double-stranded RNA viruses could have evolved from a common ancestor virus that contained genes for RNA-dependent RNA polymerase, a chymotrypsin-related protease that also functioned as the capsid protein, and possibly an RNA helicase. 相似文献
999.
S. Parakh E. R. Perri C. J. Jagaraj A. M. G. Ragagnin 《Critical reviews in biochemistry and molecular biology》2013,48(6):623-651
Rab GTPases are becoming increasingly implicated in neurodegenerative disorders, although their role in amyotrophic lateral sclerosis (ALS) has been somewhat overlooked. However, dysfunction of intracellular transport is gaining increasing attention as a pathogenic mechanism in ALS. Many previous studies have focused axonal trafficking, and the extreme length of axons in motor neurons may contribute to their unique susceptibility in this disorder. In contrast, the role of transport defects within the cell body has been relatively neglected. Similarly, whilst Rab GTPases control all intracellular membrane trafficking events, their role in ALS is poorly understood. Emerging evidence now highlights this family of proteins in ALS, particularly the discovery that C9orf72 functions in intra transport in conjunction with several Rab GTPases. Here, we summarize recent updates on cellular transport defects in ALS, with a focus on Rab GTPases and how their dysfunction may specifically target neurons and contribute to pathophysiology. We discuss the molecular mechanisms associated with dysfunction of Rab proteins in ALS. Finally, we also discuss dysfunction in other modes of transport recently implicated in ALS, including nucleocytoplasmic transport and the ER-mitochondrial contact regions (MAM compartment), and speculate whether these may also involve Rab GTPases. 相似文献
1000.
《Animal biotechnology》2013,24(1):77-86
This paper reports on the development of a small-insert (~700 bp) total-genomic library for sheep specifically designed for enrichment for microsatellite (ms) loci. Four enriched libraries were prepared by amplification of the primary library with CA15, CA11, TG15 and TG11 oligonucleotide primers. A total of 11,020 clones was recovered, screened for dinucleotide repeats and over 500 positive clones sequenced. Sequence analysis indicated low clone redundancy and yielded 105 new ovine ms loci. Seventy-two percent of the new loci were found to be polymorphic in the sires of the AgResearch International Mapping Flock (IMF). The 105 new microsatellite loci increase the number of microsatellites available for sheep by >7%. 相似文献