Effect of Jieyuwan on depression-like behaviors and expression of BDNF in hippocampus and prefrontal cortex of WKY rats

AIM:To investigate the mechanism of depression and its development, and to study the expression of brain-derived neurotrophic factor (BDNF) in the hippocampus and prefrontal cortex of Wistar-Kyoto (WKY) rats treated with Jieyuwan. METHODS:Adult male WKY rats were used as an animal model of endogenous depression. Wistar rats of the same strain were selected as control group. WKY rats were randomly divided into model group, citalopram group and Jieyuwan group. After intragastric administration for 21 d, the changes of depression-like behaviors were observed by sucrose preference test and forced swimming test. Immunofluorescence and Western blot were used to detect the expression of BDNF in the hippocampus and prefrontal cortex. RESULTS:WKY rats showed significant depression-like behaviors, and the expression of BDNF was significantly decreased in the hippocampus and prefrontal cortex (P<0.01). The reduction of neuronal axons in hippocampus was also observed. After drug treatment, the depression-like behaviors of WKY rats were significantly attenuated, and the expression of BDNF and the number of axons were increased (P<0.01). CONCLUSION:Jieyuwan effectively attenuates the depression-like behaviors of WKY rats, and BDNF is a key factor in its antidepressant effect. Our findings further confirm the involvement of BDNF in the development of depression.     

秦川牛近交与近交衰退的分析

本文分析了陕西省秦川牛场秦川牛群近交及其对初生重、断奶重及哺乳期成活率的影响,并采用标准群体遗传学模型分析了秦川牛的致死当量。研究发现,30多年来秦川牛群平均近交系数呈明显的上升趋势,而且近交对成活率、初生重及断奶重均有一定危害;秦川牛群体的隐性有害基因含量较少,平均每个个体约携带2.05个致死当量。     

库车坳陷克深地区现今地应力场及储层裂缝数值模拟

克深三维区目前处于勘探开发的前期,需要明确地应力场及地下储层裂缝的分布规律,指导开发工作,但该区存在地层埋深大、取心困难、成像测井资料缺乏等实际情况,应力场研究及裂缝预测难度大。利用有限元分析方法,以井点现今地应力值为约束进行了克深三维区现今地应力场的数值模拟,同时建立了应力应变与裂缝参数的定量关系模型,利用古今应力场结合法对克深三维区的裂缝参数进行了预测,模拟结果显示构造高部位和断层带是低应力值区及裂缝的有利发育区。裂缝的数值模拟结果与测井解释结果对比表明,预测结果与实钻吻合度较高,裂缝预测效果较好。     

Influence of chronic corticosterone injection on depression-like behavior and brain glycogen levels in mice

AIM: To study the effect of chronic corticosterone (CORT) injection on the depression-like behaviors and the brain glycogen level in mice. METHODS: Male C57BL/6N mice (n=40) were randomly divided into normal control group and model group. The mice in model group were subcutaneously consecutively injected with CORT for 4 weeks. The mouse model of chronic stress depression was constructed. The forced swim test and open field experiment were conducted to prove chronic stress model. The serum level of CORT in the mice was measured by radioimmunoassay. The protein levels of hippocampal synaptophysin (SYP) and brain-derived neurotrophic factor (BDNF) were detected by Western blot. Hippocampus glycogen, glycogen synthase and glycogen phosphorylase were determined by indirect fluorescence measurement. RESULTS: Compared with normal control group, the immobility time of the forced swim test in model group was significantly lengthened (P<0.01), and the ability of spontaneous activity was reduced (P<0.01), indicating that chronic CORT injection induced depression-like behaviors in mice. The CORT level increased significantly (P<0.01) in model group. CORT injection decreased the protein expression of hippocampal SYP and BDNF (P<0.01), reduced hippocampal glycogen level (P<0.05) and glycogen synthase activity (P<0.05), and increased glycogen phosphorylase activity (P<0.05). CONCLUSION: Chronic CORT injection causes hippocampal neuron damage and induces the depression-like behaviors of mice, which may be associated with decreasing hippocampal glycogen level by CORT.     

海河低平原盐渍涝洼区表层土壤积盐影响因素通径分析

采用通径分析方法研究海河低平原盐渍涝洼区表层土壤积盐因素的主次关系结果表明 ,地下水埋深2～ 3m、表层土壤全盐量≤ 5 0g/kg、地表高差≤ 6 6cm地段 ,表层土壤盐渍度主要受心土层盐分状况和微地形因素支配 ,而 6个间接作用中亚表土层全盐量通过心土层全盐量对表层土壤盐分累积的作用最大。     

Using ecological niche modelling to identify diversity hotspots for the herpetofauna of Pacific lowlands and adjacent interior valleys of Mexico

This article documents the conservation status of the herpetofauna in the Pacific lowlands and adjacent Balsas Basin and Chiapas Depression regions and the presents the results of modelling species spatial distributional patterns through GARP analysis, to identify hotspots of species richness, endemic and geographically restricted species in the study area. It also compares the distribution of these hotspots with the distribution of protected areas and intact seasonally tropical dry tropical forests, the dominant vegetation type in the study area and experiencing high deforestation rates. A total of 301 reptiles and amphibian species occur in the study area accounting for a third of the Mexican herpetofauna, and recording high levels of endemism and endangerment. Hotspots of species richness and endemism were located in coastal Jalisco, a considerable portion of the Colima state, as well as scattered areas in Michoacán, Guerrero, and Oaxaca. These areas should receive highest priority for protection. Unfortunately, there was a minimum correspondence when comparing the distribution of actually and proposed protected areas with hotspots identified. Fortunately, areas of high species richness, endemism and restricted species coincided with those where intact seasonally tropical dry tropical forests still exists. These areas should receive high priority in future plans for seasonally tropical dry tropical forests protected areas. It is hoped that this paper will call attention to the need for establishing a network of protected areas in the study area, as has been proposed by previous studies.     

Centimetre-scale digital representations of terrain and impacts on depression storage and runoff

The microscale topography of a 20 × 10 m hillslope in a burned portion of Kootenay National Park, British Columbia, Canada was determined through laser scanning at a sub-centimetre scale. Digital terrain models (DTM) were developed for this hillslope at the 0.75 cm, 10 cm, 25 cm, 50 cm, 75 cm and 1 m scales. Random Roughness, Tortuosity and Mean Upslope Depression were computed for bare and vegetated surfaces created at each resolution to determine mean depression storage as a function of resolution. Results for these various roughness parameters and associated depression storage values are not found to change appreciably between the vegetated and bare surface DTMs, and moreover do not change notably with increasing grid cell resolution. Depression storage was also computed using a GIS-based method, the values of which are considered to be, at the highest resolution of 0.75 cm, the most realistic for comparative purposes. Mean depression storage using this latter approach decreases significantly with an increase in grid cell size, in contrast to the values based on Random Roughness which remain stable with increasing grid cell size. The generation of Hortonian overland flow was modelled at different scales using the GIS-derived DTMs. The values of depression storage for the various scales of DTM are demonstrated to have significant influences on overland flow generation. The scale of the DTM affects the changes over time between the proportion of water going into depression storage and that contributing to overland flow, with more water being retained as depression storage at a particular value of rainfall excess after infiltration for the smaller DTM scalings. When overland flow develops from a rising groundwater table in a simulation exercise, water depths are initially lower than the primary roughness elements on the land surface and water is relatively disconnected. As water depths increase, more integrated connections form.     

Change of depression-like behavior in chronic alcoholism and withdrawal model,and co-mechanism of depression and chronic alcoholism in mice

AIM: To investigate the behavior of depression in chronic alcoholism and withdrawal model of mice, and to explore the co-mechanism of alcoholism and depression. METHODS: A novel model of chronic alcoholism was constructed in this study. The animals were divided into normal control group, and alcohol 7 d, 14 d, 21 d and 28 d groups. The mice were given alcohol preference test on the 6th, 13th, 20th and 27th days. After the test, alcohol were withdrawn for 1 d, then the next day the mice were given behavior test of depression. After the test, the mice were sacrificed. The contents of 5-hydroxytryptamine (5-HT) and norepinephrine (NE) were detected by HPLC. The expression of cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) was detected by Western blot. RESULTS: The mice showed an obvious drinking phenomenon, and the immobility time of forced swimming test and tail suspension test was significantly increased, with increasing drinking days and withdrawal times. 5-HT level in 7 d group mice only increased in frontal cortex (P < 0.05). However, compared with control group, 5-HT levels in hippocampus and cortex were decreased on the 21th and 28th days (P < 0.01). NE levels in 21 d and 28 d groups were decreased in hippocampus and frontal cortex (P < 0.05), and no significant change was observed in 7 d and 14 d groups. The protein levels of p-CREB and BDNF were significantly decreased in hippocampus and frontal cortex of 12 d and 28 d groups (P < 0.05), and no significant change was observed in 7 d group and 14 d group. CONCLUSION: The co-mechanism of alcoholism, withdrawal and depression is related to 5-HT. 5-HT-cAMP-CREB-BDNF signaling pathway may be a common mechanism for alcoholism and depression.     

Fluoxetine regulates hippocampal synaptic plasticity in CUMS depression rats

AIM: To investigate the role of fluoxetine in the hippocampal synaptic plasticity in chronic unpredictable mild stress (CUMS) depression rats and its effect on mTOR and autophagy signaling pathways. METHODS: Male Sprague-Dawley rats (n=60) were randomly divided into normal control group, CUMS group and fluoxetine group. The CUMS rat model was established through CUMS combined with solitary raising, and fluoxetine (20 mg·kg^-1·d^-1) was administered via intragastric gavage. The changes of body weight, the ratio of sugar intake and the results of the behavioral test were recorded to identify the modeling. Moreover, the expression of synaptic plasticity-related proteins glial fibrillary acidic protein (GFAP) and synaptophysin (SYP), apoptosis-related proteins Bcl-2 and caspase-3, mTOR signaling proteins mTOR and 4EBP1, and autophagy-related proteins beclin 1 and LC3 were examined by RT-PCR and Western blot.RESULTS: Compared with control group, the body weight, sucrose intake, and total distance and intermediate residence time in the open field test were significantly decreased in CUMS group. The results of RT-PCR and Western blotting showed that the mRNA and protein levels of SYP and GFAP in CUMS group were significantly down-regulated compared with control group. The expression of Bcl-2 in CUMS group was downregulated, while the protein level of cleaved caspase-3 increased. Decreased phosphorylation levels of mTOR and its downstream target molecule 4EBP1 were observed in CUMS group. Besides, the autophagy-related proteins beclin 1 and LC3 were significantly upregulated at mRNA and protein levels. All these results(upregulation or downregulation) were attenuated by the treatment with fluoxetine, and the difference was statistically significant. CONCLUSION: Fluoxetine might improve hippocampal synaptic plasticity and alleviate symptoms of depression by supressing apoptosis/autophagy signaling pathways and upregulating mTOR signaling pathway.