Nucleus accumbens long-term depression and the expression of behavioral sensitization

Drug-dependent neural plasticity related to drug addiction and schizophrenia can be modeled in animals as behavioral sensitization, which is induced by repeated noncontingent or self-administration of many drugs of abuse. Molecular mechanisms that are critical for behavioral sensitization have yet to be specified. Long-term depression (LTD) of alpha-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid receptor (AMPAR)-mediated synaptic transmission in the brain has been proposed as a cellular substrate for learning and memory. The expression of LTD in the nucleus accumbens (NAc) required clathrin-dependent endocytosis of postsynaptic AMPARs. NAc LTD was blocked by a dynamin-derived peptide that inhibited clathrin-mediated endocytosis or by a GluR2-derived peptide that blocked regulated AMPAR endocytosis. Systemic or intra-NAc infusion of the membrane-permeable GluR2 peptide prevented the expression of amphetamine-induced behavioral sensitization in the rat.     

Newborn minor physical anomalies predict short attention span, peer aggression, and impulsivity at age 3

From a 5-to 10-minute newborn examination, behaviors of males at age 3 could be predicted. The number of minor physical anomalies, assessed soon after birth, was significantly related to a cluster of behaviors that are frequently labeled hyperactivity.     

1,25-dihydroxyvitamin D3 receptors in human leukocytes

A 1,25-dihydroxyvitamin D3 receptor macromolecule was detected in peripheral mononuclear leukocytes from normal humans. This macromolecule was found to be present in monocytes but absent from normal resting peripheral B and T lymphocytes. However, it was present in established lines of malignant B, T, and non-B, non-T human lymphocytes, as well as in T and B lymphocytes obtained from normal humans and activated in vitro.     

Structure of the human dopamine D3 receptor in complex with a D2/D3 selective antagonist

Dopamine modulates movement, cognition, and emotion through activation of dopamine G protein-coupled receptors in the brain. The crystal structure of the human dopamine D3 receptor (D3R) in complex with the small molecule D2R/D3R-specific antagonist eticlopride reveals important features of the ligand binding pocket and extracellular loops. On the intracellular side of the receptor, a locked conformation of the ionic lock and two distinctly different conformations of intracellular loop 2 are observed. Docking of R-22, a D3R-selective antagonist, reveals an extracellular extension of the eticlopride binding site that comprises a second binding pocket for the aryl amide of R-22, which differs between the highly homologous D2R and D3R. This difference provides direction to the design of D3R-selective agents for treating drug abuse and other neuropsychiatric indications.     

1 alpha, 25-Dihydroxyvitamin D3 nuclear receptors in pituitary

Specific binding of 1 alpha,25-dihydroxyvitamin D(3) was found in nuclear and cytosol fractions of the bovine pituitary. For nuclear binding. the dissociation constant was 0.1 namomole per liter, and maximum binding was 104 femtomoles per milligram of protein. In competition studies, 25-hydroxyvitamin D(3) was 300 times weaker than 1 alpha,25-dihydroxyvitamin D(3). The existence of high-affinity sites supports a physiologic role for 1 alpha,25-dihydroxyvitamin D(3) in the pituitary.     

Positron emission tomography reveals elevated D2 dopamine receptors in drug-naive schizophrenics

In postmortem studies of patients with schizophrenia, D2 dopamine receptors in the basal ganglia have been observed to be more numerous than in patients with no history of neurological or psychiatric disease. Because most patients with schizophrenia are treated with neuroleptic drugs that block D2 dopamine receptors in the caudate nucleus, it has been suggested that this increase in the number of receptors is a result of adaptation to these drugs rather than a biochemical abnormality intrinsic to schizophrenia. With positron emission tomography (PET), the D2 dopamine receptor density in the caudate nucleus of living human beings was measured in normal volunteers and in two groups of patients with schizophrenia--one group that had never been treated with neuroleptics and another group that had been treated with these drugs. D2 dopamine receptor densities in the caudate nucleus were higher in both groups of patients than in the normal volunteers. Thus, schizophrenia itself is associated with an increase in brain D2 dopamine receptor density.     

ATP release guides neutrophil chemotaxis via P2Y2 and A3 receptors

Cells must amplify external signals to orient and migrate in chemotactic gradient fields. We find that human neutrophils release adenosine triphosphate (ATP) from the leading edge of the cell surface to amplify chemotactic signals and direct cell orientation by feedback through P2Y2 nucleotide receptors. Neutrophils rapidly hydrolyze released ATP to adenosine that then acts via A3-type adenosine receptors, which are recruited to the leading edge, to promote cell migration. Thus, ATP release and autocrine feedback through P2Y2 and A3 receptors provide signal amplification, controlling gradient sensing and migration of neutrophils.     

日光温室二维及三维模拟对温度模拟结果的影响

数值模拟在温室环境研究中应用日趋广泛,正确选择温室模拟模型对模拟结果的准确性非常重要。本研究以温室夜间各表面的温度为边界条件,采用CFD软件对12m跨度温室温度环境进行二维及三维空间的稳态模拟求解。结果表明温室中间横剖面温度在三维模拟及二维模拟中空间变化趋势相同且与测试结果相近：在温室前部及温室后上部模拟值与测试值的绝对误差在5％以内,在温室中部尤其是近土壤表面误差偏大。由温室中间及距山墙1m远两个横剖面的1m高温度线分布对比结果可见,温室长度大于其跨度两倍以上时,山墙对室内中部温度环境的影响不明显,模拟温室中部横剖面的温度用二维模型可行。     

Ca2+ entry through plasma membrane IP3 receptors

Inositol 1,4,5-trisphosphate receptors (IP3Rs) release calcium ions, Ca2+, from intracellular stores, but their roles in mediating Ca2+ entry are unclear. IP3 stimulated opening of very few (1.9 +/- 0.2 per cell) Ca2+-permeable channels in whole-cell patch-clamp recording of DT40 chicken or mouse B cells. Activation of the B cell receptor (BCR) in perforated-patch recordings evoked the same response. IP3 failed to stimulate intracellular or plasma membrane (PM) channels in cells lacking IP3R. Expression of IP3R restored both responses. Mutations within the pore affected the conductances of IP3-activated PM and intracellular channels similarly. An impermeant pore mutant abolished BCR-evoked Ca2+ signals, and PM IP3Rs were undetectable. After introduction of an alpha-bungarotoxin binding site near the pore, PM IP3Rs were modulated by extracellular alpha-bungarotoxin. IP(3)Rs are unusual among endoplasmic reticulum proteins in being also functionally expressed at the PM, where very few IP3Rs contribute substantially to the Ca2+ entry evoked by the BCR.     

基于ArcEngine与Skyline的二三维联动GIS系统的设计研究

二维GIS有成熟的理论与技术,特别是分析能力较好,但对用户来说不够直观.三维GIS在最近几年发展势头迅猛且拥有良好的表达效果,但其分析功能尚待提高.如需结合各自的优点,则需要在同一框架下实现二三维联动.该研究分析了二三维联动GIS开发环境的选择及功能设计思路,基于ArcGIS Engine和Skyline软件实现了二三维联动系统的设计与开发.     

二三维一体化环境安全防控系统的设计与实现

为了有效监管城市环境状况、及时预防和处理城市环境安全事故,以环境数据中心为依托,采用"平战结合"的建设思路,以应急指挥调度为核心,构建环境安全防控系统,该系统实现了对存在于废水企业、废气企业、污水处理厂、河流、城市空气等的风险源信息以及与之关联的环境信息和应急资源等的综合管理。并基于二三维一体化GIS平台,实现了综合预警、GIS定位、空间分析、扩散模拟、GPS定位等辅助决策功能。从环境安全预防、预警、应急3个方面实现环境安全的全过程监管。该系统成功应用于山东省17地市的环保部门,为环境安全工作提供了决策依据,提升了区域环境安全防控能力。     

二三维联动自然灾害应急管理系统的设计

我国是自然灾害最严重的国家之一,建立自然灾害应急管理系统可以减少灾害损失,是应对突发性自然灾害的有效措施。充分结合二维GIS与三维GIS的优势,设计了二三维联动操作模式下的灾害应急管理GIS系统,其具有分析实时灾情信息、制定快速救援方案、指挥现场救援等功能,可以为突发性自然灾害的应急指挥工作提供决策支持。     

D2类山羊草细胞质普通小麦核代换系育性在不同光温条件下的差异

将D2类山羊草[粗厚山羊草（Ae.crassa)、牡山羊草（Ae.juvenalis)和瓦维洛夫山羊草（Ae.vavilovii)]细胞质普通小麦核代换系于1997－1998年分别种植在不同纬度的5个地点，并进行分期播种。从不同地点核代换系和核亲本的育性表现，分析D2类山羊草细胞质核代换系对日长、温度的敏感性及其差异。结果表明：（1）D2类山羊草细胞质小麦核代换系的3种类型存在差异，粗厚山羊草对日长、温度反应最为敏感，其次是瓦维洛夫山羊草，牡山羊草对光周期较钝感。（2）日长和温度两种生态因子对D2类山羊草细胞质核的育性变异的作用程度不同，日长是主控因子，温度在日长因子相近时方显示其作用。（3）核质互作是D2类山羊草细胞质小麦核代换系育性对光温反应的遗传方式。     

基于RS和GIS的二三维一体化农业生态监测技术研究

GIS技术已经在农业生态领域得到了广泛的应用,实现了对农业生态环境信息的空间和属性信息的一体化分析和综合处理,实现的方式还集中于二维角度;采用二三维相结合的方式进行生态监测,并以云南省老君山示范区为例,介绍了农业生态二三维一体化可视化系统的设计,从二维和三维角度实现对该示范区内的城镇、矿山、道路的影响的判断,达到监测预警的目的。通过实践证明了将农业生态监测模型与GIS技术结合,应用二三维一体化进行可视化分析,可为农业生态保护提供全新的空间技术支持方法。     

水稻长穗颈高秆隐性基因eui2的分子标记和定位

以协青早eB-2和矮脚南特杂交的F3为分析群体,用AFLP分子标记技术及BSA分析方法筛选出4个多态性片段E1、E2、E3和E4与eui2连锁,其中E1被定位于第10染色体长臂中部RFLP标记G291和G2155之间,与G291相距4.7cM,与G2155相距13.1cM.用SSR标记RM304、RM258、RM269、RM271和E1构建的eui2基因的局部分子标记连锁图表明,eui2基因位于分子标记E1和RM304之间,二者距eui2的遗传距离分别为0.6和1.4cM.     

可溶性MICA对外周血淋巴细胞受体NKG2D、CD69表达的影响

为了分析可溶性MHCⅠ类相关分子A(sM ICA)对淋巴细胞活化性受体NKG 2D及早期活化标志性受体CD 69表达的影响,从U 937细胞中经RT-PCR扩增出sM ICA的cDNA片段,经酶切后插入原核表达载体pQE 3.1,并命名为pQEM ICA。IPTG大量诱导表达后溶解包涵体,所得6个H is重组蛋白经N i 树脂纯化、稀释复性,最后与外周血单个核细胞作用。结果发现sM ICA蛋白可抑制NKG 2D的表达,并通过NKG 2D的下调而抑制CD 69的表达。该研究不仅为探讨sM ICA分子对淋巴细胞特别是NK细胞生物学特性影的研究响奠定基础,也为探讨M ICA介导的肿瘤免疫逃逸机制提供工具。     

WO3复合La2/3Ca1/3MnO3的磁电阻效应与导电行为研究

采用溶胶-凝胶法制备了不同摩尔比的WO3复合La2/3Ca1/3MnO3(LCMO)样品,探讨了零场下LCMO样品的阻温关系及在不同磁场下的磁电阻效应.分析了体系在高温区和低温区的导电行为,并在此基础上讨论了磁场对导电机制的影响及起因.     

O3与O3/H2O2两个体系降解除草剂2,4-D反应特性研究

分别采用O3、O3/H2O2体系降解苯氧羧酸类除草剂2,4-D,探讨了降解过程中反应温度、pH值、O3混合气流量、有机物初始浓度等操作条件的变化对降解动力学的影响。结果发现,温度和pH值的影响较大,O3流量影响最小,温度升高、pH值增大、臭氧流量增加、2,4-D初始浓度降低均有助于降解速率的提高。O3/H2O2体系中,H2O2能促进O3分解产生大量自由基,导致2,4-D反应活化能降低。和O3相比,O3/H2O2体系降解效果好,降解时间短,反应条件温和,操作费用低,是很有发展前景的高级氧化技术。     

HYDRUS-1D／2D在土壤水分入渗过程模拟中的应用

介绍了HYDRUS-1D／2D软件的特点及其组成,并以古尔班通古特沙漠融雪水入渗过程为例,基于各项土壤物理特征参数,应用该软件模拟了沙漠垄间及垄顶距树干不同距离处的土壤含水量随入渗时间的变化过程,并以实测数据进行验证,模拟效果良好。总结了模型应用步骤、该软件的优点。     

香蕉穿孔线虫28S rRNA基因的D2/D3区序列分析

采用线虫通用引物D2A和D3B对9个香蕉穿孔线虫种群的核糖体DNA 28S大亚基的D2/D3区进行了扩增,获得的片段长度约为780 bp,克隆测序后使用UPGMA法进行聚类分析和构建系统发育树.结果表明9个线虫种群D2/D3区核苷酸序列相似性为99.13%,其中8个群体的序列与越南报道的香蕉穿孔线虫近源种(Radopholus sp.7B VietNam)的D2/D3区核苷酸序列(DQ328712)相似性为97.46%,说明香蕉穿孔线虫D2/D3区具有较大的保守性.聚类分析结果表明,RSHN12r、RSSH、RSHL、RSHK、RSLZ、RSSZ、RSHN13、RSHN12p等8个种群聚为一类,亲缘关系很近,RSHN3群体与以上8个群体亲缘关系较远,说明RSHN12r、RSSH、RSHL、RSHK、RSLZ、RSSZ、RSHN13、RSHN12p这8个香蕉穿孔线虫种群可能来源于同一地理种群,而RSHN3种群可能来源于另一个地理种群.