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Oxidative stress in neurodegenerative diseases

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Neural Regeneration Research 2012年第5期7卷 376-385页

作者： Xueping Chen Chunyan Guo jiming kong Department of Human Anatomy and Cell Science University of Manitoba Manitoba Canada Department of Pharmacy Hebei North University Zhangjiakou 075000 Hebei Province China

Reactive oxygen species are constantly produced in aerobic organisms as by-products of normal oxygen metabolism and include free radicals such as superoxide anion （02-） and hydroxyl radical （OH-）, and non-radical hydrogen peroxide （H202）. The mitochondrial respiratory chain and enzymatic reactions by various enzymes are endogenous sources of reactive oxygen species. Exogenous reactive oxygen species -inducing stressors include ionizing radiation, ultraviolet light, and divergent oxidizing chemicals. At low concentrations, reactive oxygen species serve as an important second messenger in cell signaling; however, at higher concentrations and long-term exposure, reactive oxygen species can damage cellular macromolecules such as DNA, proteins, and lipids, which leads to necrotic and apoptotic cell death. Oxidative stress is a condition of imbalance between reactive oxygen species formation and cellular antioxidant capacity due to enhanced ROS generation and/or dysfunction of the antioxidant system. Biochemical alterations in these macromolecular components can lead to various pathological conditions and human diseases especially neurodegenerative diseases. Neurodegenerative diseases are morphologically featured by progressive cell loss in specific vulnerable neuronal cells, often associated with cytoskeletal protein aggregates forming inclusions in neurons and/or glial cells. Deposition of abnormal aggregated proteins and disruption of metal ions homeostasis are highly associated with oxidative stress. The main aim of this review is to present as much detailed information as possible that is available on various neurodegenerative disorders and their connection with oxidative stress. A variety of therapeutic strategies designed to address these pathological processes are also described. For the future therapeutic direction, one specific pathway that involves the transcription factor nuclear factor erythroid 2-related factor 2 is receiving considerable attention.

关键词： oxidative stress neurodegenerative diseases reactive oxygen species therapy reviews

Deformation and Development Tendency of Shiliushubao Landslide by Numerical Modeling

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 840-846页

作者： LI Xiuzhen kong jiming XU Qiang Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China School of Civil Engineering Southwest Jiaotong University Chengdu 610031 Sichuan China College of Environment and Civil Engineering Chengdu University of Technology Chengdu 610059 Sichuan China

On the basis of analysing basic features of Shiliushubao landslide, the landslide＇s deformation and development tendency are quantitatively studied by using FLA^3D program. The results accord with monitoring results. The results are indicated that resevoir impounding accelerates the landslide＇s deformation, and the variation of reservoir water level is key factor of affecting the deformation; The landslide has the characters of pull-behind move ment according to the displacement of the landslide body gradually reducing from leading edge to trailing edge; Excavating and deloading slow down the landslide＇s deformation in the certain degree. On the basis, the deformation developmental tendency of Shiliushubao landslide is predicted by the established simulating model.

关键词： Shiliushubao landslide deformation rule develop ment tendency numerical modeling

Occurrence Conditions and Process Analysis on Fluidization of Valley Type Landslide:Example of the Fluidization of Landslide in Qiongshan Ravine, Danba

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 829-834页

作者： kong jiming CHEN Zefu SONG Shuzhi Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China Graduate University of the Chinese Academy of Sciences Beijng 100049 China

A big debris flow which was arosed by landslide occurrence at night on July 11, 2003 in Qiongshan Ravine, Danba, Sichuan Province. According to the research, debris flow in Qiongshan Ravine is arosed by the fluidization of landslide. It had been rained about 70 days before debris flow occurred. That made the sediments in the gully to near to saturated or saturated in water. Being affect by the steep geography, the sediments occurrence peristalsis to transform, parts of soil bodies start disintegrate. All the sediments become transforming with water inleakaging to sediments, and than foreside slope flow to gully quickly after becoming fluidization. And the sediments come into being the debris flow with the water of the gully joining.

关键词： Danba in Sichuan Province fluidization of landslide occurrence condition occurrence process

Dynamical Mechanisms of Effects of Landslides on Long Distance Oil and Gas Pipelines

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 820-824页

作者： MA Qingwen WANG Chenghua kong jiming Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China Graduate University of Chinese Academy of Sciences Beijing 100049 China

According to the investigations on the oil and gas pipelines such as the Lan-Cheng-Chong pipeline and the Southwest pipeline, there are two ways of laying pipeline： pipelines paralleling （approximately） to the main slide direction and pipelines perpendicular （approximately） to the main slide direction. If earth-retaining walls have been built for pipelines paralleling to the main slide direction, they will prevent the lands from sliding; On the contrary, without earth-retaining walls, the sharp broken rocks in the backfilling soil will scratch the safeguard of the pipeline when the landslides take place. Pipelines perpendicular to the main slide direction can be classified into four types according to the relative positions between pipelines and landslides： Pipelines over the slide planes, pipelines inside the fracture strips of slide planes, pipelines below the slide planes and pipelines behind the backsides of landslides. The different dynamical mechanisms of the process in which landslide acts against pipelines are analyzed based on whether the pipelines are equipped with fixed frusta, because the sliding resistance depends on whether and how many fixed frusta are equipped and the distance between frusta.

关键词： landslide long distance oil and gas pipeline dynamical mechanism

Fetal cell microchimerism in the maternal mouse spinal cord

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Neuroscience Bulletin 2014年第1期30卷 81-89页

作者： Guohui Zhang Yunan Zhao Xin-Min Li jiming kong Department of Forensic Medicine Hebei North University Department of Human Anatomy and Cell Science Faculty of Medicine University of Manitoba Department of Psychiatry University of Manitoba

Fetal cell microchimerism refers to the persistence of fetal cells in the maternal tissues following pregnancy. It has been detected in peripheral organs and the brain, but its existence in the spinal cord has not been reported. Our aim was to detect fetal cell microchimerism in the spinal cord of maternal mice. C57BL/6 female mice were crossed with GFP transgenic male mice and sacrificed after their first or third delivery. GFP-positive cells, which were presumably from fetuses whose fathers were GFP transgenic, were detected in the spinal cord by fluorescence microscopy and immunohistochemistry. PCR was also performed to detect GFP DNA, which must come from GFP hemizygous fetuses. We found GFP-positive cells and detectable GFP DNA in most of the maternal spinal cords. Twenty percent （1/5） of the mice that were only pregnant once had detectable fetal cells, while 80% （4/5） of those that were pregnant three times had detectable fetal cells. Some fetal cells, which not only emitted green fluorescence but also expressed NeuN, were detected in the spinal cords from maternal mice. These results indicate that fetal cells migrate into the spinal cord of a maternal mouse during and/or after the gestational period, and the fetal cells may differentiate into neurons in the spinal cord.

关键词： fetal cell microchimerism greenfluorescent protein spinal cord mouse

Criterions and Measures of Route Selection of Shallowly Embedded Long-Distance Oil and Gas Pipeline in Mountain Areas

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 787-792页

作者： WANG Chenghua MA Qingwen kong jiming CHEN Zefu LI Xiuzhen Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China Graduate university of Chinese Academy of Sciences Beijing 100049 China

According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows： the flat landform is the first choice in route alignment. The foot of mountain is the first choice when the route passes by the valley. The route should pass by but the shady and deposited slope and not in sunny and erosive slope as possible as it can. The pipeline should be vertical to contour climbing and descending the mountain except steep slope. Tunnel can be used in crossing foothill. Perpendicularly traversing the river is better than beveling; the worst choice is to put the pipeline along the river. Bypass is the best choice in karsts area. The order of route selection should be pre-choosing, investigation, optimization and adjustment.

关键词： shallowly embedded long-distance oil and gas pipeline criterions and measures of route selection avoiding geological hazards

Analysis of Rockfall and Its Impact on the Cut-and-Cover Tunnel in Dynamics

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 905-909页

作者： SONG Shuzhi kong jiming WANG Chenghua CHENG Zefu YANG Zongji Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 SichuanChina Graduate University of Chinese Academy of Sciences Beijing 100049 China

This paper presents the effect of thickness of Buffer layer on the safety of cut-and-cover tunnel under the given magnitude and height of rockfall, and the limit load of the structure. To establish calculating models of rockfall in different conditions, the dynamics of the fall down to the surface of the slope is taken into account and the exterior characteristics of the rockfall is analyzed. We have derived the formula for calculating velocity of rocks before and after collision, calculated the impact load upon the structures below and the limit load, and compared the impact force and limit load to judge the safety of the structure. Finally, the validity of models is approved by the safety evaluation of cut-and-cover tunnel in the mouth of Heshang Mountain in Nandan County.

关键词： rockfall cut-and-cover tunnel (CCT) impact force buffer layer

Forecast Method of Multimode System for Debris Flow Risk Assessment in Qingping Town,Sichuan Province,China

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Journal of Mountain Science 2011年第4期8卷 592-602页

作者： kong jiming Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The Wenchuan Earthquake of May 12,2008 triggered large numbers of *** heavy rain on 13 August 2010 triggered debris flows with total volume of more than 6 million cubic meters and the debris flows destroyed 500 houses and infrastructure built after the Wenchuan *** study area Qingping Town was located in the northwestern part of the Sichuan Basin of China,which needs the second reconstructions and the critical evaluation of debris *** study takes basin as the study unit and defines collapse,landslide and debris flow hazard as a geo-hazard system.A multimode system composed of principal series system and secondary parallel system were established to evaluate the hazard grade of debris flow in 138 drainage basins of Qingping *** evaluation result shows that 30.43% of study basins(42 basins) and 24.58% of study area,are in extremely high or high hazard grades,and both percentage of basin quantity and percentage of area in different hazard grades decrease with the increase of hazard *** to the geo-hazard data from the interpretation of unmanned plane image with a 0.5-m resolution and field investigation after the Wenchuan Earthquake and 8.13 Big Debris Flow,the ratio of landslides and collapses increased after the Wenchuan Earthquake and the ratios of extremely high or high hazard grades were more than moderate or low hazard grades obviously.23 geo-hazards after8.13 Big Debris Flow in Qingping town region all occurred in basins with extremely high or high hazard grades,and 9 debris flows were in basins with extremely high hazard *** model of multimode system for critical evaluation could forecast not only the collapse and landslide but also the debris flow precisely when the basin was taken as the study unit.

关键词： Multimode System Risk assessment Debris flow Landslide Wenchuan Earthquake Qingping Town

Locomotor activity and anxiety status, but not spatial working memory,are affected in mice after brief exposure to cuprizone

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Neuroscience Bulletin 2013年第5期29卷 633-641页

作者： Handi Zhang Yanbo Zhang Haiyun Xu Lingyan Wang Jinsong Zhao Junhui Wang Zhijun Zhang Qingrong Tan jiming kong Qingjun Huang Xin-Min Li Mental Health Center Shantou University Department of Psychiatry Faculty of Medicine University of Manitoba Department of Cardiology China-Japan Friendship Hospital of Jilin University Department of Ophthalmology Second Hospital of Jilin University Department of Neuropsychiatry ZhongDa Hospital Affiliated with Southeast University Department of Psychiatry Xijing Hospital Fourth Military Medical University Department of Human Anatomy and Cell Science University of Manitoba

Chronic long-term exposure to cuprizone causes severe brain demyelination in mice,which leads to changes in locomotion,working memory and *** findings suggest the importance of intact myelin for these *** study aimed to investigate the possible behavioral changes in mice with mild oligodendrocyte/myelin damage that parallels the white matter changes seen in the brains of patients with psychiatric *** used the cuprizonetreated mouse model to test both tissue changes and behavioral functions（locomotor activity,anxiety status,and spatial working memory）.The results showed that mice given cuprizone in their diet for 7 days had no significant myelin breakdown as evaluated by immunohistochemical staining for myelin basic protein,while the number of mature oligodendrocytes was *** number and length of Caspr protein clusters,a structural marker of the node of Ranvier,did not *** locomotor activity of the cuprizonetreated mice increased whereas their anxiety levels were lower than in normal controls;spatial working memory,however,did not *** results,for the first time,link emotion-related behavior with mild white matter damage in cuprizone-treated mice.

关键词： myelination oligodendrocyte locomotor activity anxiety spatial working memory cuprizone mouse