Roles of endogenous nitric oxide in acute mountain sickness

Acute mountain sickness (AMS) is the greatest challenge of military medicine and wilderness medicine, as the increasing populations of entering Tibet and others who rapidly ascend to high altitude. AMS is considered as a kind of vascular dysfunction and disequilibrium of body fluid diseases induced by environmental stress. Studies reveal that endogenous nitric oxide (NO), a predominant endogenous vessel dilator, plays a crucial role in the pathogenesis of AMS. The decreased production and blocked delivery of NO cause dysfunction of the vascular system in hypoxic situations. Subsequently, AMS develops under the facilitations of alterations in brain and pulmonary blood vessels. NO or L-arginine (the precursor of NO) can also be used to prevent and treat AMS. This review will summarize the progress on the roles of NO in the pathogenesis, pathophysiology, treatment and prophylaxis of AMS.     

瘦素受体表达量在苏钟猪脂肪沉积调控中的作用

瘦素受体（leptin receptor,LEPR）在机体的体质量平衡、造血、生殖、血管生成和免疫过程中发挥着重要作用。为进一步了解LEPR基因在苏钟猪脂肪沉积调控中的作用机制,本研究利用Real-time PCR方法和Western-blot方法分析该基因在12头苏钟猪中5个脂肪易沉积组织（心脏、肝脏、肾脏、背膘和眼肌）RNA和蛋白水平的表达谱信息。结果表明：LEPR的mRNA在这5种组织中均有表达,其在各组织中的mRNA表达丰度表现为：背膘〉眼肌〉心脏〉肝脏〉肾脏,其中在背膘的表达量极显著高于其他几种组织（P〈0.01）;LEPR蛋白在这5种组织中也均有表达,其中在心脏中的表达量最高,显著高于其他组织（P〈0.01）,且在公猪组织的表达量显著高于母猪组织（P〈0.05）;另外,LEPR第18外显子在苏钟猪群中检测到3个高突变率的SNPs。LEPR对苏钟猪的背膘、肌肉、心脏、肾脏、肝脏等组织的脂肪沉积有重要影响,是苏钟猪肉质改良育种中潜在的重要候选基因。     

Effects of different mulching practices on the photosynthetic characteristics of hot pepper (Capsicum annuum L.) in a greenhouse in Northwest China

Mulching is considered a desirable management technology for improving and stabilizing agricultural crop production. The aim of the present study was to evaluate the effect of different mulching practices on hot pepper (Capsicum annuum L.) performance in terms of leaf photosynthetic capacity, photosynthetic light response (PLR) curves, and growth parameters, under greenhouse conditions. Consequently, field experiments were conducted during the 2011 and 2012 growing seasons in Northwest China using four types of mulching practices (without mulch; wheat straw mulch; plastic film mulch; and combined mulch with plastic film and wheat straw). The results showed that mulching increased the leaf net photosynthesis rate, stomatal conductance to water vapor, intercellular CO₂ concentration, water-use efficiency, and transpiration rate. Mulching significantly affected the PLR curves, and important parameters (such as the apparent quantum yield, maximum net photosynthetic rate, light compensation point, and light saturation point) were all improved under combined mulching conditions when compared with other mulching practices. Therefore, it is inferred that hot pepper leaf photosynthetic capacity and light-use efficiency were significantly improved under combined mulching, and thereby the combined mulching is recommended for hot pepper cultivation in greenhouses due to working well to facilitate soil condition (moisture and temperature), plant growth, and marketable photosynthetic characteristics.     

Simulation of groundwater table dynamics based on Feflow in the Minqin Basin,China

As groundwater table declination is an important factor resulting in degradation of eco-environment in the Minqin Basin,China,it is significant to investigate and understand the groundwater table dynamics in this area. According to the physical and geographical conditions of the Minqin Basin,a hydrogeological conceptual model and a mathematical model were established,and the mathematical model was figured out by using Finite Element subsurface Flow system(Feflow).Accurate hydrogeological parameters were acquired,and the spatio-temporal distribution dynamics of groundwater table for 1983–2001 were also simulated.The model performed well with a correlation coefficient of 0.977 and a mean error of 0.9768 m.The inflow and outflow of the groundwater system were predicted by time series analysis,and the groundwater table dynamics for 2011 were further acquired.Generally the groundwater table in the Minqin Basin would continue to decline.The groundwater table would decline during spring and summer irrigation,while it would rise during autumn-winter irrigation.The groundwater depression cones would expand with the increase of center depths.Therefore,regulatory measures should be taken to prevent the declination of groundwater table and improve the eco-environment of this area.     

急性和亚慢性镉处理对溪蟹鳃组织影响的比较

为了比较研究急性和亚慢性镉处理对河南华溪蟹(Sinopotamon henanense)鳃组织病理学和生物化学的影响,设置了急性(4d,28.55 mg/L Cd2+)和亚慢性(21 d,2.86 mg/L Cd2+)镉处理组及对照组.将处理组和对照组的部分鳃组织采用光学显微技术进行组织病理学的观察,对剩余鳃组织分别采用比色法、火焰原子吸收法和镉-血红蛋白饱和法检测了总超氧化物歧化酶(SOD)活性、膜脂质过氧化产物丙二醛(MDA)含量、Cd2+蓄积和金属硫蛋白(MT)含量,并计算了MT的镉结合率(CBP).结果显示,急性镉处理后鳃叶肥大增厚,部分上皮细胞中出现空泡；亚慢性处理后,鳃叶边缘通道紧缩,上皮细胞高度肿胀,鳃血腔缩小变窄.所检测指标在处理组中显著高于对照组,其中Cd2+蓄积量和SOD活性在两个处理组之间没有显著差异,急性处理组MT含量显著高于亚慢性组,而亚慢性组MDA含量显著高于急性组.表明亚慢性镉处理对河南华溪蟹鳃组织结构的损伤程度比急性组严重,可能与亚慢性组鳃的MT含量低,脂质过氧化程度高有关.     

生态文明研究综述

就生态文明的内涵、特点及国内研究现状进行了归纳与总结,在分析国内生态文明实践的基础上从建立生态型政府、发展生态文明经济、探索切实可行的生态文明指标体系等方面提出了建议。     

Effects of human bone morphogenetic protein 2 and 9 on proliferation,apoptosis and migration of human gastric carcinoma MNK-45 cells

AIM: To investigate the effects of human bone morphogenetic protein 2 (BMP2) and BMP9 on the proliferation, apoptosis and migration of human gastric carcinoma cell line MNK-45. METHODS: Immunocytochemical staining, MTT assay, wound-healing test, Transwells migration test, Hoechst 33258 staining and flow cytometry (FCM) were used to determine the infection of AdBMP2 and AdBMP9 on the proliferation, apoptosis and migration of MNK-45 cells. The expression of GSK-3β (including p-GSK-3β and total GSK-3β) and β-catenin in MNK-45 cells was also detected by Western blotting. RESULTS: The proliferation of MNK-45 cells was inhibited from the third day on and in a time-dependent manner after infected with AdBMP2 and AdBMP9. The results of Hoechst 33258 staining and FCM proved that apoptosis rates in BMP2 group and BMP9 group were higher than that in GFP group. Both wound-healing test and Transwell experiment indicated that up-regulating the expression of BMP2 and BMP9 inhibited the migration of MNK-45 cells. The phosphorylation levels of GSK-3β in BMP2 group and BMP9 group were higher than that in GFP group. However, no significant change of β-catenin among groups was observed. CONCLUSION: Up-regulation of BMP2 and BMP9 expression inhibits the proliferation of MNK-45 cells.