The Effect of Tai Chi Training on Cardiorespiratory Fitness in Healthy Adults: A Systematic Review and Meta-Analysis

BackgroundTai Chi may be efficient for healthy adults to improve the cardiorespiratory fitness, but there is no systematic evaluation for its effectiveness.ObjectiveTo systematically assess the effectiveness of Tai Chi on cardiorespiratory fitness in healthy adults.MethodsSeven electronic databases were searched from their inception to October 2013. The controlled trails including randomized controlled trial (RCT), non-randomized controlled trial (NRCT), self-controlled trial (SCT), and cohort study (CS) testing Tai Chi exercise against non-intervention control conditions in healthy adults that assessed any type cardiorespiratory fitness outcome measures were considered. Two reviewers independently performed the selection of the studies according to predefined criteria. The risk of bias was assessed using Cochrane criteria. RevMan 5.2 software was applied for data analysis.ResultsTwenty studies (2 RCTs, 8 NRCTs, 3 SCTs, and 7 CSs) with 1868 participants were included, but most of them belonged to low methodological quality. The results of systematic review showed that Tai Chi exercise had positive effect on majority outcomes of cardio function (Blood pressure: n = 536, SPB SMD = -0.93, 95% CI -1.30 to -0.56, P < 0.00001; DBP SMD = -0.54, 95% CI -0.90 to -0.18, P < 0.00001; heart rate at quiet condition: n = 986, SMD = -0.72, 95% CI -1.27 to -0.18, P = 0.010; stroke volume: n = 583, SMD = 0.44, 95% CI 0.28 to 0.61, P < 0.00001; cardio output: n = 583, MD = 0.32 L/min, 95% CI 0.08 to 0.56, P = 0.009), lung capacity (FVC at quiet condition: n = 1272, MD = 359.16 mL, 95% CI 19.57 to 698.75, P = 0.04 for less than one year intervention, and MD = 442.46 mL, 95% CI 271.24 to 613.68, P<0.0001 for more than one year intervention; V·O₂peak: n = 246, SMD = 1.33, 95% CI 0.97 to 1.70, P < 0.00001), and cardiorespiratory endurance (O₂ pulse at quiet condition: n = 146, SMD = 1.04; 95% CI 0.69 to 1.39; P < 0.00001; stair test index at quiet condition: n = 679, SMD = 1.34, 95% CI 0.27 to 2.40, p = 0.01). No adverse events were reported.ConclusionsThe results are encouraging and suggest that Tai Chi may be effective in improving cardiorespiratory fitness in healthy adults. However, concerning the low methodological quality in the included studies, more larger-scale well-designed trails are needed till the specific and accurate conclusions can be perorated.     

运动执行前认知成分的脑成像研究及实验范式

对运动任务的准备包含着一定的认知加工过程,这些运动执行前的认知成分涉及到相应的脑神经机制,它们可能彼此独立,有时则相互重叠。本文拟对相关领域的脑成像研究及其实验范式进行综述。     

A systematical analysis of tryptic peptide identification with reverse phase liquid chromatography and electrospray ion trap mass spectrometry

In this study we systematically analyzed the elution condition of tryptic peptides and the characteristics of identified peptides in reverse phase liquid chromatography and electrospray tandem mass spectrometry (RPLC-MS/MS) analysis. Following protein digestion with trypsin, the peptide mixture was analyzed by on-line RPLC-MS/MS. Bovine serum albumin (BSA) was used to optimize acetonitrile (ACN) elution gradient for tryptic peptides, and Cytochrome C was used to retest the gradient and the sensitivity of LC-MS/MS. The characteristics of identified peptides were also analyzed. In our experiments, the suitable ACN gradient is 5% to 30% for tryptic peptide elution and the sensitivity of LC-MS/MS is 50 fmol.Analysis of the tryptic peptides demonstrated that longer (more than 10 amino acids) and multi-charge state ( 2, 3) peptides are likely to be identified, and the hydropathicity of the peptides might not be related to whether it is more likely to be identified or not. The number of identified peptides for a protein might be used to estimate its loading amount under the same sample background. Moreover, in this study the identified peptides present three types of redundancy, namely identification, charge, and sequence redundancy, which may repress low abundance protein identification.     

不同来源甜高粱种质资源的表型遗传多样性分析

通过对主要农艺性状的方差分析及聚类分析,对194份不同来源的甜高粱种质资源进行了表型性状的遗传多样性分析。结果表明,不同来源品种间的性状差异较大,与中国品种相比,国外品种具有植株高大、生物产量高及含糖量高等优异性状,可用于国内资源的种质创新及品种改良。遗传距离为0.66时将所有资源划分为6类,各类群主要按农艺性状进行了划分。研究结果将为杂交育种的亲本选择提供理论参考。     

Effects of d-Amino Acids on the EPS Production and Cell Aggregation of Alteromonas macleodii Strain JL2069

Exopolysaccharide (EPS) is produced by many marine bacteria and is important for cell aggregation in the ocean. d-amino acids are important components in bacteria and are recently recognized as signal molecules for regulation of bacterial growth. In this study, the effects of d-amino acids on EPS production, cell aggregation, and metabolic activity were investigated using an EPS-producing bacterium Alteromonas macleodii strain JL2069. EPS produced by JL2069 was inhibited by 1 mM of d-Ala and d-Ser, but not by d-Glu. The formation of particulate organic matter (POM) was promoted by the three amino acids. A new technique of microcalorimetry analysis indicated that the metabolic activity of the JL2069 cells was inhibited by these d-amino acids. Our results suggested that d-amino acids may reduce the bacterial metabolism by changing bacterial lifestyle from planktonic to cell aggregation growth which occurs independent of the production of EPS.     

氟的危害及控制

环境中氟的危害是环境科学及卫生学界极为关注的问题。氟的过多吸收 ,对动植物及人体会产生危害[1 ,2 ] 。研究氟危害的表现特征及机理 ,目的是为了控制或减轻氟危害。综合评价氟的测定方法 ,在氟污染调查和环境质量评价中 ,有切实的实用价值。1　氟对植物及土壤微生物的毒害作用土壤氟污染对作物的危害是慢性积累的生理障碍过程。氟能抑制作物的新陈代谢、呼吸作用[3] 及光合作用[2 ] ,抑制新陈代谢过程中马来酸脱氢酶的活性[4] 。氟对作物的危害主要表现为干物质积累量少、产量降低、分蘖少、成穗率低、光合组织受损伤 ,出现叶尖坏死 ,叶…     

盐地碱蓬幼嫩花序的组织培养及植株再生

选用盐地碱蓬(Suaedasalsa)幼嫩花序为外植体,建立了快速而高效的离体培养体系。在附加1.0mg.L-16-BA和0.4mg.L-1IAA的MS培养基上培养25天可诱导出不定芽,诱导频率达到82.1%;不定芽在此培养基上可快速扩增和长期继代培养。不定芽转至MS培养基中培养2￣3周生根形成完整植株。     

诱导耐药K562/ADM和转基因耐药K562/MDR细胞株的生物学行为和耐药机制的比较研究

目的探讨转多药耐药基因mdr1的K562/MDR细胞株作为单机制耐药模型的可行性,为进一步研究肿瘤耐药及其逆转奠定基础。方法实验分为3部分:(1)在电子显微镜下观察慢性髓细胞白血病急性红白变敏感细胞系K562,阿霉素(adriamycin,ADM)诱导耐药细胞株K562/ADM和K562/MDR耐药细胞株的生物学行为;同时测定3种细胞系的群体倍增时间;以观察药物诱导和基因转移是否对细胞的生物学行为造成影响。(2)以K562细胞为对照,用MTT法分别测定阿霉素、柔红霉素(daunorubicin,DNR)、长春新碱(vincristine,VCR)对3种细胞的半数致死量(IC50)。(3)多药耐药相关基因与蛋白的检测。免疫细胞化学法观察mdr1基因编码的P-糖蛋白(P-gp)的表达;流式细胞术检测P-gp、bcl-2的表达百分率;生化法测定细胞内谷胱甘肽S-转移酶(GSTs)活性;RT-PCR法检测拓扑异构酶(to-poisomeraseⅡ,topoⅡ)mRNA的表达变化。结果(1)在超微结构上,K562/ADM的细胞器—线粒体出现水肿,K562和K562/MDR未见明显异常;K562的群体倍增时间为19.67±3.10d;K562/MDR为20.40±1.80d;K562/ADM为28.47±1.75d;(2)K562/ADM和K562/MDR细胞对ADM的耐药倍数分别为23.1和1.2倍;对DNR为84.9和14.4倍;对VCR为298.3和10.1倍。(3)与K562比较,K562/ADM细胞的P-gp和Bcl-2蛋白表达率高且topoⅡcDNA片段大小发生变化;K562/MDR仅P-gp表达率高。结论K562/MDR的生物学行为与亲本细胞K562相似,耐药机制单一,可作为单机制耐药模型,对某一耐药基因进行更为深入精确的研究,也可针对该耐药基因准确地筛选相应的逆转剂。