A comparison of throwing kinematics between youth baseball players with and without a history of medial elbow pain

Risk factors in throwing factors associated to little league elbow have not been adequately explored. Whether these factors also affect the players' performance is also important to elucidate while modifying throwing pattern to reduce injury. The purpose of this study was to compare the differences in throwing kinematics between youth baseball players with or without a history of medial elbow pain (MEP) and to determine the relationship between their throwing kinematics and ball speed. Fifteen players with previous MEP were matched with 15 healthy players by age, height and weight. Throwing kinematics was recorded by an electromagnetic motion analysis system. A foot switch was used for determining foot off and foot contact. Ball speed was recorded with a sports radar gun. The group with a history of MEP demonstrated less elbow flexion angle at maximum shoulder external rotation and had more lateral trunk tilt at ball release compared to the healthy group. The group with a history of MEP also had faster maximum upper torso rotation velocities, maximum pelvis rotation velocities and ball speeds. Maximum shoulder external rotation angle (r = 0.458, P = 0.011), elbow flexion angle at maximum shoulder external rotation (r = -0.637, P = 0.0003), and maximum upper torso rotation velocity (r = 0.562, P = 0.002) had significant correlation with ball speed. Findings of this study can be treated as elbow injury-related factors that clinicians and coaches can attend to when taking care of youth     

长尾小蜂属中国一新纪录属及一新纪录种(膜翅目,长尾小蜂科)

记述长尾小蜂科Torymidae中国1新纪录属突喙长尾小蜂属Rhynchoticida,及中国1新纪录种尾突喙长尾小蜂Rhynchoticida caudate Bou(c)ek,1978.突喙长尾小蜂属Rhynchoticida的鉴别特征为:触角粗而短;胸部黑,被密柔毛;后足基节侧面光裸区具大而深的半月形刻点;后足腿节膨大,其腹面具1排较宽的齿;腹部突起.提供了形态描述、寄主、分布及形态特征图.研究标本保存在中国科学院动物研究所动物标本馆.     

北京百花山自然保护区不同植被地面生苔藓植物物种多样性

采用相似性系数和物种多样性指数对北京百花山自然保护区8种植被内地面生苔藓植物的物种多样性进行了研究,得知8种植被中地面生苔藓植物有13科31属65种（含种以下的单位）,优势科6科,优势种12种。不同植被中苔藓植物的物种组成、优势科和优势种不同,丛藓科和真藓科植物在草甸和灌丛内占绝对优势,而森林植被内的绢藓科为绝对优势科;油松林和落叶阔叶混交林的物种相似性最高为51.63,草甸和荆条灌丛与大部分植被的物种相似为0。地面生苔藓植物的分布与其生长的基质相关性最大,另外水分条件、小生境、草本层盖度和凋落物盖度等也影响地面生苔藓植物的分布。白桦林和落叶阔叶混交林应成为生物多样性保护的重点植被类型。     

Nocturnal CPAP improves walking capacity in COPD patients with obstructive sleep apnoea

Background

Exercise limitation is an important issue in patients with chronic obstructive pulmonary disease (COPD), and it often co-exists with obstructive sleep apnoea (overlap syndrome). This study examined the effects of nocturnal continuous positive airway pressure (CPAP) treatment on walking capacity in COPD patients with or without obstructive sleep apnoea.

Methods

Forty-four stable moderate-to-severe COPD patients were recruited and completed this study. They all underwent polysomnography, CPAP titration, accommodation, and treatment with adequate pressure. The incremental shuttle walking test was used to measure walking capacity at baseline and after two nights of CPAP treatment. Urinary catecholamine and heart rate variability were measured before and after CPAP treatment.

Results

After two nights of CPAP treatment, the apnoea-hypopnoea index and oxygen desaturation index significantly improved in both overlap syndrome and COPD patients, however these changes were significantly greater in the overlap syndrome than in the COPD group. Sleep architecture and autonomic dysfunction significantly improved in the overlap syndrome group but not in the COPD group. CPAP treatment was associated with an increased walking capacity from baseline from 226.4 ± 95.3 m to 288.6 ± 94.6 m (P < 0.05), and decreased urinary catecholamine levels, pre-exercise heart rate, oxygenation, and Borg scale in the overlap syndrome group. An improvement in the apnoea-hypopnoea index was an independent factor associated with the increase in walking distance (r = 0.564).

Conclusion

Nocturnal CPAP may improve walking capacity in COPD patients with overlap syndrome.

Trial registration

{"type":"clinical-trial","attrs":{"text":"NCT00914264","term_id":"NCT00914264"}}NCT00914264     

多聚磷酸盐及其代谢酶的研究进展

多聚磷酸盐(polyP)是由几个到几百个无机磷酸盐单体通过高能磷酸键聚合而成的线性多聚体,广泛分布于自然界和生物体.本文总结了polyP在生物体中的重要功能,包括基因表达和调控、DNA的摄取、微生物的运动性、对胁迫和饥饿的应答、病原菌的毒性以及对细胞凋亡、血液凝固、细胞钙化、线粒体功能的调节,需要polyP的酶有内切酶、葡萄糖激酶、NAD激酶和AMP磷酸转移酶等.本文对调控polyP的多聚磷酸盐激酶(polyphosphate kinase,ppk)和外切聚磷酸酶(exopolyphosphatase,PPX )的生化性质和结构也进行了总结.同时,结合我们的研究工作,重点分析了结核分枝杆菌中PPX的同源蛋白和可能的生物化学活性.     

平腹小蜂属中国三新纪录种(膜翅目,旋小蜂科)

记述了中国平腹小蜂属Anastatus Motschulsky中国3新纪录种:克什米尔平腹小蜂Anastatus kashmirensis Mathur,科氏平腹小蜂Anastatus colemani Crawford和细索平腹小蜂Anastatus tenuipes Bolivary Pieltain;编制了分种检索表.研究标本保存在中国科学院动物研究所动物标本馆.     

Isolation and anti-fatty liver activity of a novel cerebroside from the sea cucumber Acaudina molpadioides

Cerebrosides are a kind of important bioactive substance in sea cucumber. A novel cerebroside, AMC-2, was purified from the less-polar lipid fraction of the sea cucumber Acaudina molpadioides by repeated column chromatography. The major structure of AMC-2 was analyzed by gas chromatography-mass spectra. The amide-linked fatty acid unit was confirmed to be four saturated and monounsaturated α-hydroxy fatty acids, the long-chain base was dihydroxy sphingoid base with one double bond, and the glycosyl group was glucose. We also investigated the anti-fatty liver activity of AMC-2 in rats with fatty liver induced by orotic acid. AMC-2 significantly reduced hepatic triglyceride (TG) and total cholesterol (TC) levels at a diet supplement of 0.03% and 0.006%. The indexes of stearoyl-CoA desaturase (SCD) activity and mRNA expression were significantly decreased by AMC-2. This indicates that AMC-2 ameliorated nonalcoholic fatty liver disease (NAFLD) through suppression of SCD activity and impaired the biosynthesis of monounsaturated fatty acids in the livers of the rats.     

温度及种子含水量对剪枝栎实象和青冈象卵发育的影响

剪枝栎实象Mechoris ursulu和青冈象Curculio megadens是危害多种壳斗科植物坚果的重要害虫,在长期与寄主的相互作用中已进化出相应的反防御策略.了解两种象甲与植物间的相互关系,可有助于对其进行科学防治.本文通过温度等因子对具有相近生态位的剪枝栎实象和青冈象卵发育影响的比较研究,探讨产卵于寄主组织内的两种象甲卵期与植物防御的相互关系及青冈象的适应进化策略.结果显示,温度对剪枝栎实象和青冈象卵的发育历期有显著影响.在15～30℃内,两种象甲卵的发育历期逐渐缩短,发育速率加快;相同温度下青冈象卵的历期比剪枝栎实象长.温度对剪枝栎实象和青冈象卵的存活有显著影响.在15～25℃内,两种象甲卵的存活率逐渐增高;相同温度下剪枝栎实象卵的存活率高于青冈象卵的存活率.种子含水量对两种象甲卵的历期及存活率无显著影响,但相同含水量下剪枝栎实象卵的存活率高于青冈象卵的存活率.青冈象卵及卵室均明显小于剪枝栎实象,其卵的大小为0.0836 mm3,卵室为0.4650 mm3;剪枝栎实象卵的大小为0.2368 mm3,卵室为3.9589 mm3.研究结果可为进一步探讨两种象甲与寄主植物的相互关系及青冈象的适应进化奠定理论基础.     

蝶呤型钼辅因子生物合成、运输及组装——潜在的药物靶标

钼辅因子作为氧化还原反应中的重要分子,参与硫、氮、碳的氧化还原代谢.钼辅因子主要分为两类:以铁硫簇为基础的铁钼辅因子和以亚钼蝶呤为基础的钼辅因子.钼-二-亚钼蝶呤-鸟苷二核苷钼辅因子(Mo-bis-MGD)是蝶呤型钼辅因子的重要成员之一,是硝酸盐还原酶的重要辅因子.膜结合硝酸盐还原酶介导的硝酸盐还原为细菌提供了氮源和能...     

An automated microfluidic chip system for detection of piscine nodavirus and characterization of its potential carrier in grouper farms

Groupers of the Epinephelus spp. are an important aquaculture species of high economic value in the Asia Pacific region. They are susceptible to piscine nodavirus infection, which results in viral nervous necrosis disease. In this study, a rapid and sensitive automated microfluidic chip system was implemented for the detection of piscine nodavirus; this technology has the advantage of requiring small amounts of sample and has been developed and applied for managing grouper fish farms. Epidemiological investigations revealed an extremely high detection rate of piscine nodavirus (89% of fish samples) from 5 different locations in southern Taiwan. In addition, positive samples from the feces of fish-feeding birds indicated that the birds could be carrying the virus between fish farms. In the present study, we successfully introduced this advanced technology that combines engineering and biological approaches to aquaculture. In the future, we believe that this approach will improve fish farm management and aid in reducing the economic loss experienced by fish farmers due to widespread disease outbreaks.