Long noncoding RNA PTENP1 affects the recovery of spinal cord injury by regulating the expression of miR-19b and miR-21

Exosomes derived from differentiated P12 cells and MSCs were proved to suppress apoptosis of neuron cells, and phosphatase and tensin homolog pseudogene 1 (PTENP1) was reported to inhibit cell proliferation. In this study, we aimed to investigate the role of PTENP1 in the process of post-spinal cord injury (SCI) recovery, so as to evaluate the therapeutic effects of exosomes derived from MSCs transfected with PTENP1 short hairpin RNA (shRNA), as a type of novel biomarkers in the treatment of SCI. Electron microscopy was used to observe the morphology of different exosomes. Real-time polymerase chain reaction and western blot, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, flow cytometry, Nissl staining, immunohistochemistry assay, and terminal deoxynucleotidyl transferase dUTP nick end labeling assay were conducted to investigate and validate the underlying molecular signaling pathway. PTENP1-shRNA downregulated PTENP1 and PTEN while upregulating miR-21 and miR-19b. PTENP1-shRNA also accelerated cell apoptosis and reduced cell viability. In addition, PTENP1 reduced the miR-21 and miR-19b expression by directly targeting miR-21 and miR-19b. Meanwhile, both miR-21 and miR-19b reduced the expression of PTEN by directly targeting the 3′-untranslated region of PTEN. Furthermore, PTEN level and apoptosis index of neuron cells was the highest in the SCI group, while the treatment with exosomes+PTENP1-shRNA reduced the PTEN expression to a level similar to that in the sham group. Finally, PTENP1 inhibited miR-21 and miR-19b expression but upregulated PTEN expression. The upregulation of miR-21/miR-19b also suppressed the apoptosis of neuron cells by downregulating the PTEN expression. PTENP1 is involved in the recovery of SCI by regulating the expression of miR-19b and miR-21, and exosomes from PTENP1-shRNA-transfected cells may be used as a novel biomarker in SCI treatment.     

Assessing the importance of a self-generated detachment process in river biofilm models

1. Epilithic biofilm biomass was measured for 14 months in two sites, located up‐ and downstream of the city of Toulouse in the Garonne River (south‐west France). Periodical sampling provided a biomass data set to compare with simulations from the model of Uehlinger, Bürher and Reichert (1996: Freshwater Biology, 36 , 249–263.), in order to evaluate the impact of hydraulic disturbance. 2. Despite differences in application conditions (e.g. river size, discharge, frequency of disturbance), the base equation satisfactorily predicted biomass between low and high water periods of the year, suggesting that the flood disturbance regime may be considered a universal mechanism controlling periphyton biomass. 3. However modelling gave no agreement with biomass dynamics during the 7‐month long low water period that the river experienced. The influence of other biomass‐regulating factors (temperature, light and soluble reactive phosphorus) on temporal biomass dynamics was weak. 4. Implementing a supplementary mechanism corresponding to a temperature‐dependent self‐generated loss because of heterotrophic processes allowed us to accurately reproduce the observed pattern: a succession of two peaks. This case study suggests that during typical summer low water periods (flow stability and favourable temperature) river biofilm modelling requires self‐generated detachment to be considered.     

血革螨科二新种（蜱螨亚纲）

本文记述了血革螨科两新种:大理血革螨Haemogamasus daliensis sp.nov.和中华真厉螨Eulaelaps sinensis sp.nov.。该文对新种的形态特征作了描述,并与近似种进行了比较。     

中国的角石蛾属昆虫(毛翅目:角石蛾科)

McLachlan(1866)根据采自印度北部阿萨姆Assam的一只雄虫,描述新种灰翅角石蛾Stcnopsyche griseipennis McLachlan并做为模式种,而建立角石蛾属StenopsycheMcLachlan,置于纹石蛾科Hydropsychidae.Ulmer(1907)将前人称之的纹石蛾科分为纹石蛾科(狭义),多距石蛾科Polycentropidae等翅石峨科Philopotomidae和管石蛾科Psychomyiidae。他根据角石蛾属有3个单眼和前足胫节有3个距而置于等翅石蛾科中;但角石蛾属在翅形、脉相、体躯大小和外生殖器等方面与等翅石蛾科的差别极为明显。Banks(1913)认为Ulmer所述的4科,仅能被认为是纹石蛾科中的4个亚科,他将角石     

A mutant hemolysin with lower biological activity produced by a mutant Vibrio parahaemolyticus

Abstract A mutant toxin (m-TDH) of thermostable direct hemolysin (Vp-TDH) of Vibrio parahaemolyticus w was isolated from the culture of a strain of this organism mutagenized with N -methyl- N '-nitro- N -nitrosoguanidine. Although the m-TDH had a molecular structure similar to the native Vp-TDH, the m-TDH retained only about 7% residual hemolytic activity of the native toxin. Furthermore, other biological activities of m-TDH, such as lethality in mice and enterotoxicity in rabbit ileal loops, were also weakened. The m-TDH was immunologically indistinguishable from the native Vp-TDH. These results suggest that the m-TDH is only slightly different in structure from the native Vp-TDH. Also, the mutagenized site in m-TDH, which is not immunogenic, seems to be involved in expressing not only hemolytic activity but also lethal and enterotoxic activity.     

电针引起脊髓P物质释放的频率依赖性

我室以往的研究表明,不同频率的电针可引起脊髓释放不同种类的阿片肽。本工作观察Ｐ物质（ＳＰ）释放的频率依赖性,电针频率选择２,４,８,１５,３０和１００Ｈｚ,分别收集电针期间及电针前后各３０ｍｉｎ的脊髓灌流液,通过放射免疫方法测定大鼠电针有效组和电针无效组Ｐ物质免疫活性（ＳＰ－ｉｒ）．结果如下：（１）电针有效组：２Ｈｚ引起ＳＰ－ｉｒ降低,与电针前相比,Ｐ＜０．０１;４Ｈｚ电针前后ＳＰ－ｉｒ比较,无统计学意义;８,１５,３０,１００Ｈｚ时ＳＰ－ｉｒ均增加（Ｐ＜０．０１）,其中１５Ｈｚ时ＳＰ增加最多（Ｐ＜０．００１）,表明刺激引起ＳＰ释放有频率依赖性。（２）电针无效组：不论应用何种频率,电针前后脊髓灌流液中ＳＰ－ｉｒ变化不大（均Ｐ＞０．０５）。提示,电针时脊髓液中ＳＰ含量变化与镇痛效果有密切关系。     

尖三刺角蝉的核型与性二型现象：同翅目：角蝉科

尖三刺角蝉Ｔｈｉｃｅｎｔｒｕｓａｃｕｔｉｃｏｒｎｉｓ的雌雄均只有１０条染色体,性别决定为ＸＹ型,是角蝉科已知最为独特的核型特征,该种具有明显的性二型现象,由于雄性不具有上肩角,极易被误认为是秃角蝉属ＣｅｎｔｒｏｔｏｓｃｅｌｌｕｓＦｕｎｋｈｏｕｓｅｒ的种类。本文根据染色体特征,首次确定了该种的雄性,并对其形态特征进行了描述。     

心脏肾素－血管紧张素系统在游泳引起的生理性心肌肥大中的作用

本实验采用游泳训练（ＳＷ）引起的大鼠心肌肥大模型,通过放射免疫及生化等方法,对生理性心肌肥大时,心脏和循环肾素－血管紧张素系统（ＲＡＳ）的变化进行了初步研究。观察到游泳五周时,大鼠左、右心室重与体重比值（Ｖ／Ｂｗｔ）显著升高,同时,左、右室心肌血管紧张素Ⅱ（ＡｎｇⅡ）含量及心肌Ａｎｇ转换酶（ＡＣＥ）活性也较对照组明显升高（Ｐ＜０．０５）。心肌ＡｎｇⅡ与Ｖ／Ｂｗｔ之间存在明显的正相关关系（ｒ＝０．７７２１,Ｐ＜０．００１）。ＳＷ组血浆ＡｎｇⅠ,Ⅱ及肾素活性（ＲＡ）与对照组相比无明显差异,其血浆ＡｎｇⅡ与Ｖ／Ｂｗｔ之间无明显相关性。上述研究提示：心脏ＲＡＳ在ＳＷ引起的生理性心肌肥大中可能起着重要作用,而且这种作用在很大程度上不依赖于循环ＲＡＳ。     

遮阴对石笔木苗木生长和保护酶活性的影响

为探讨石笔木Tutcheria championi苗木对遮阴环境的适应性,以全光照(无遮阴覆盖)为对照,研究遮阴30%、50%和70%对2年生石笔木苗生长和生理特性的影响。结果表明,全光照下石笔木苗木生长较为健壮,其苗高、地径生长优于遮阴处理;全光照下石笔木总生物量、根生物量比以及根冠比显著大于遮阴处理(P<0.05);50%遮阴处理苗木叶片叶绿素含量显著高于全光照和70%遮阴处理(P<0.05),叶绿素a/b值在各处理间无显著差异。丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性在各处理间无显著差异(P>0.05);70%遮阴处理的苗木叶片过氧化氢酶(CAT)活性最高,显著高于全光照和50%遮阴。由此表明,充足的光照环境有利于石笔木苗木生长。