肉仔鸡卫星细胞氧化应激时MAPK信号通路

 【目的】在地塞米松(DEX)诱导骨骼肌卫星细胞氧化应激的体外条件下,筛选丝裂原活化蛋白激酶(MAPKs)信号系统中起关键作用的信号通路。【方法】 将体外培养的肉仔鸡胸肌骨骼肌卫星细胞(SCs)分别进行处理：Ⅰ、对照组;Ⅱ、DEX;Ⅲ、p38 MAPK抑制剂;Ⅳ、DEX+p38 MAPK抑制剂;Ⅴ、JNK抑制剂;Ⅵ、DEX+JNK抑制剂;Ⅶ、ERK5抑制剂;Ⅷ、DEX+ERK5抑制剂;Ⅸ、ERK1/2抑制剂;Ⅹ、DEX+ERK 1/2抑制剂。除处理Ⅰ和处理Ⅱ外,其它处理首先用抑制剂预处理30 min,弃去培养基后,再按处理设置分别加入含DEX的培养基或者正常培养基继续处理24 h。处理结束后,分别测定细胞培养液中丙二醛(MDA)、活性氧自由基(ROS)、超氧化物歧化酶(SOD)和谷胱甘肽硫转酶(GST)含量或活性;同时采用RT-PCR方法检测通路蛋白及SOD与GST基因表达量。【结果】 抑制剂单独处理组MDA和ROS的产生量显著低于DEX处理(P＜0.05);DEX+ERK5抑制剂处理与DEX+ERK 1/2抑制剂处理的MDA和ROS产生量显著高于ERK 5抑制剂处理和ERK1/2抑制剂处理(P＜0.05); DEX+p38 MAPK抑制剂处理与 DEX+JNK抑制剂处理组的MDA和ROS产生量与p38 MAPK处理和JNK处理的差异不显著(P＞0.05)。抑制剂单独处理组的SOD和GST活性比DEX处理高(P＜0.01);DEX+ERK5抑制剂处理与 DEX+ERK 1/2抑制剂处理的SOD和GST活性极显著低于ERK5抑制剂处理组和ERK1/2抑制剂处理组(P＜0.01),DEX+p38 MAPK抑制剂处理与DEX+JNK抑制剂处理的SOD和GST活性与p38 MAPK抑制剂处理和 JNK抑制剂处理的差异不显著(P＞0.05)。基因表达结果表明,DEX能够抑制GST和SOD基因的表达,抑制率达37%以上。与抑制ERK5和ERK1/2通路不同,抑制p38 MAPK和JNK通路后,DEX对GST和SOD基因的表达无明显抑制作用。【结论】 在DEX诱导的肉仔鸡胸肌骨骼肌SCs产生的氧化应激过程中,p38 MAPK和JNK通路起着关键作用。     

Review of research methodologies for tigers: Telemetry

Over the past half century, wildlife research has relied on technological advances to gain additional insight into the secretive lives of animals. This revolution started in the 1960s with the development of radio telemetry and continues today with the use of Global Positioning System (GPS)-based research techniques. In the present paper we review the history of radio telemetry from its origins with grizzly bears in Yellowstone to its early applications in tiger research and conservation in Asia. We address the different types of data that are available using radio telemetry as opposed to using other research techniques, such as behavioral observations, camera trapping, DNA analysis and scat analysis. In the late 1990s, the rapid development of GPS collar technology revolutionized wildlife research. This new technology has enabled researchers to dramatically improve their ability to gather data on animal movements and ecology. Despite the ecological and conservation benefits of radio telemetry, there have been few telemetry studies of tigers in the wild, and most have been on the Bengal or Amur subspecies. We close with an assessment of the current tiger conservation efforts using GPS technology and discuss how this new information can help to preserve tigers for future generations.     

Weed Management in Rice-Wheat Cropping System through Remote Sensing： A Review

The productivity of the flee-wheat rotation of the Indo-Gangetie Plains is critical to India＇s food security. Severe weed competition resulting from the change in morphological characteristics of the modem high yielding varieties （HYV） led to intensive use of herbicides for weed control. Continuous and indiscriminate use of herbicides led to pollution as well as build up of resistant biotypes. This necessitates the need based use of herbicides. Identification of predominant weeds in rice-wheat cropping system through remote sensing and Geographic Information System （GIS） would help in reducing the load of herbicide on agro-eco system by reducing spray volume, application time and non-target spraying. This will help in developing site-specific weed management technique by geating only those areas with herbicide where weed densities exceed the economic threshold and may reduce application rate of herbicides in patches where weed densities are low. This paper reviews the literature on role of remote sensing for weed management not just to review their empirical findings, but to evaluate the role they have played and have the potential to play-in actual for weed management in flee-wheat cropping system （food bowl of India）.     

The Effect of Angiotensin‐Converting Enzyme Inhibitors of Left Atrial Pressure in Dogs with Mitral Valve Regurgitation

Background: Despite many epidemiological reports concerning the efficacy of angiotensin‐converting enzyme (ACE) inhibitors in dogs with mitral regurgitation (MR), the hemodynamic effects of ACE inhibitor administration have not been fully evaluated. Objectives: To document left atrial pressure (LAP) in dogs with MR administered ACE inhibitors, in order to obtain interesting information about daily LAP changes with administration of ACE inhibitors. Animals: Five healthy Beagle dogs weighing 9.8 to 14.2 kg (2 males and 3 females; aged 2 years). Methods: Experimental, crossover, and interventional study. Chordae tendineae rupture was induced, and a radiotelemetry transmitter catheter was inserted into the left atrium. LAP was recorded for 72 consecutive hours during which each of 3 ACE inhibitors—enalapril (0.5 mg/kg/d), temocapril (0.1 mg/kg/d), and alacepril (3.0 mg/kg/d)—were administered in a crossover study. Results: Averaged diurnal LAP was significantly, but slightly reduced by alacepril (P= .03, 19.03 ± 3.01–18.24 ± 3.07 mmHg). The nightly drops in LAP caused by alacepril and enalapril were significantly higher than the daily drops (P= .03, ?0.98 ± 0.19 to ?0.07 ± 0.25 mmHg, and P= .03, ?0.54 ± 0.21–0.02 ± 0.17 mmHg, respectively), despite the fact that the oral administrations were given in the morning. Systolic blood pressure (122.7 ± 14.4–117.4 ± 13.1 mmHg, P= .04) and systemic vascular resistance (5800 ± 2685–5144 ± 2077 dyne × s/cm⁵, P= .03) were decreased by ACE inhibitors. Conclusions and Clinical Importance: ACE inhibitors decrease LAP minimally, despite reductions in left ventricular afterload. ACE inhibitors should not be used to decrease LAP.     

RESEARCH PAPER: Comparison of an implantable telemetry device and an oscillometric monitor for measurement of blood pressure in anaesthetized and unrestrained green iguanas (Iguana iguana)

Objective The objective of this study was to compare an implanted direct blood pressure monitor and a non‐invasive oscillometric unit for use in anesthetized and awake green iguanas. Study design Prospective experimental trial. Animals Four male and four female adult green iguanas (Iguana iguana) weighing 1833 ± 534 g. Methods For each animal, the carotid artery was surgically exposed and the catheter tip of the pressure transducer was placed in the aortic arch. Non‐invasive blood pressure was measured using a cuff over the left femoral region. Pulse rate, respiratory rate and arterial blood pressure (ABP) measurements were taken every 5 minutes. Direct ABP measurements consisted of recording numerical values and graphic output. Simultaneous direct and indirect measurements were repeated in awake animals. Results The oscillometric device failed to provide a reading in over 80% of attempts, and failed to provide readings that correlated with direct measurements. The implanted direct transducer was capable of detecting blood pressures throughout all ABP ranges examined. Conclusions The implantable transducer was a reliable means of determining blood pressure in this study, while the oscillometric device was unreliable and often failed to provide any reading. Clinical relevance We do not recommend using the oscillometric device as described in a research or clinical setting for green iguanas. The advantages of an implantable device include the ability to monitor awake and anesthetized subjects remotely and continuously. These monitors are small, biocompatible and function across a wide range of ABP.     

西南林区卫星监测热点及森林火险天气指数分析

根据国家林业局林火监测中心提供的2005—2007年卫星监测到的热点数据及相关信息和研究区及其周边2004—2007年34个气象站的每日定时观测数据,计算森林火险天气指数(FWI)系统各组分指数,分析西南地区森林火险和热点的分布规律。结果表明:2005—2007年西南地区热点主要分布在云南、广西和贵州西南部,44.6%的热点可能是野外植被燃烧引起的,这些热点包括草原、灌丛、森林和荒地上的火烧以及计划烧除、炼山等,云南西南和南部有大量的农业用火(占所有热点的30.1%)。西南地区的火烧主要发生在11月—翌年5月,1—5月份发生的火烧占全部热点的77.6%。森林火灾集中分布在云南东部和西北部、贵州东南部和广西大部分地区。热点数与相应区域的腐殖质湿度码(DMC)和干旱码(DC)的变化密切相关,森林火险期内DMC和DC值较高,热点和森林火灾多。热点数与FWI值存在显著的相关关系,FWI系统可以应用于西南地区,并且对森林火险有很好的指示作用。根据重点研究区的FWI各组分指数情况,定义低、中、高、很高和极高森林火险分别对应的FWI阈值为0 - 1.2、1.3 - 5.0、5.1 - 12.0、12.1 - 25.0和25.1+,对应火险等级日数分别占41.0%、23.6%、21.8%、11.2%和2.4%。研究区内人为火源和农业用火较多,加强研究区内高火险天气的火源管理是减少森林火灾的重要有效措施。     

多浪绵羊骨骼肌卫星细胞的分离培养、鉴定及成肌诱导分化

为了在体外细胞水平模拟多浪绵羊肌肉生长发育过程,本研究以多浪绵羊为试验动物,采用胶原酶和胰酶两步酶消化法分离多浪绵羊骨骼肌卫星细胞（satellite cells,SCs）,并利用差速贴壁的方法纯化分离得到的SCs。利用免疫荧光技术检测SCs标记基因Desmin、Pax7和MyoD1的表达情况,鉴定分离得到的SCs。采用血清撤离的方法诱导SCs向成肌方向分化。通过显微镜观察和成肌分化标记基因肌球蛋白重链（myosin heavy chain,MHC）的免疫荧光,检测肌管的形成情况。通过对SCs标记基因Desmin、Pax7和MyoD1的免疫荧光鉴定,确认本研究成功分离得到多浪绵羊SCs。采用血清撤离的方法诱导SCs成肌分化,显微镜观察和MHC免疫荧光可以明显观察和检测到肌管的形成。本研究对多浪绵羊SCs成功地进行了分离和鉴定,并建立了体外培养条件下多浪绵羊SCs的成肌诱导分化。     

基于GIS的西藏无资料地区耕地历史经济价值评价方法

无资料地区缺少有关耕地经济价值评价的历史数据,该文以西藏省拉萨市为无资料研究区,选择夜间灯光数据,辅以数字高程模型和道路数据,基于农业区位论和GIS空间分析方法,对2010年拉萨市的耕地经济价值进行分级评价,旨在探讨一种适用于无资料地区某个历史时期的耕地经济价值评价方法,以填补该地区耕地经济价值的数据空白。首先选择城关区为试验区,基于2010年地面真实数据验证了研究方法的可行性(总精度达84%),然后以灯光亮度等级划分拉萨8县(区)的经济差异,进而将方法应用于拉萨全市,得到2010年拉萨市耕地历史经济价值评价结果,评价的总精度达82.6%,Kappa系数0.722,表明该文研究方法具有鲁棒性,可以为西藏无资料地区的耕地历史经济价值评价研究提供参考。     

利用GRACE重力卫星监测新疆天山山区水储量时空变化

利用经过高斯平滑滤波处理的2003年1月至2010年12月逐月的GRACE卫星时变重力场数据,反演得到新疆天山山区水储量变化,其空间分辨率为1°×1°,结合同时间段该区域31个国家气象台站逐月降水资料,采用趋势分析方法,研究天山山区近8 a来的水储量时空变化特征。结果表明：天山山区水储量变化具有明显的空间差异性,总体表现为东、西部多,中部少的空间分布格局。在时间上,水储量变化与降水具有明显的季节性变化规律,两者变化过程基本一致。天山山区平均水储量变化趋势的年内分布总体上1-12月呈递增变化;1-3月为负增长,最大负增长为21.7 mm•a^-1,出现在2月;4-12月呈正增长,最大月份出现在11月,增长趋势达到29.9 mm•a-¹。水储量变化增加的主要原因是天山山区近几年夏季降水有所增加造成的。2003-2010年天山山区水储量变化总体上呈逐年下降趋势,平均每月下降速度为4.8 mm,8 a间水储量变化减少约13×10⁸ m³,其主要原因是由于气候转暖、冰川消融加速、山前绿洲灌溉及生活用水量增加,导致山区水储量变化减少。     

冬小麦生物量卫星遥感估测研究

生物量是反映冬小麦长势的重要群体指标,及时、大面积获取冬小麦生物量信息有利于掌握早期冬小麦长势和产量形成动态,对于生产管理措施制定意义重大。以江淮麦区的泰兴、兴化两市大田冬小麦为研究区域,基于冬小麦生物量模型(WBM),利用环境星(HJ-1)进行冬小麦拔节期生物量监测预报研究。在提取研究区域小麦面积信息的基础上,利用泰兴市冬小麦拔节期遥感影像反演的LAI及时修订生物量模型的参数,再利用模型对兴化市冬小麦生物量信息进行预测。结果表明:(1)利用生物量模型预测的冬小麦生物量为1897.03～3800.78kg/hm2,平均为2866.33kg/hm2。实测的生物量为1932.30～3689.44kg/hm2,平均为2711.75kg/hm2,相对误差为5.70%,生物量模型的预测性较好;(2)利用预测生物量与卫星影像NDVI的转换模型,可制作冬小麦生物量预测专题图,并能准确、大面积获取不同等级生物量的冬小麦面积分布与长势信息。