神经元性一氧化氮合酶活性在app/ps1双转基因AD模型小鼠皮质和海马的分布

本实验用 4～ 5月龄和 15～ 16月龄的 app/ ps1dtg小鼠各 5只 ,同龄野生型小鼠每个年龄组各 5只 ,用β-NADPH组织化学染色显示神经元一氧化氮合酶活性 ,刚果红组织学染色显示神经炎性斑 ,无偏性体视学计量皮质和海马神经炎斑的总体积 ,研究神经元一氧化氮合酶活性在 app/ ps1双转基因 (app/ ps1dtg) AD模型小鼠大脑皮质和海马的异常分布 ,探讨其在该模型小鼠及 AD患者脑内病理改变中的作用。结果显示 ,n NOS阳性神经元在各组小鼠皮质和海马内的分布没有区别 ,4～ 5月龄 app/ps1dtg小鼠皮质和海马可见神经炎斑 (NP)和营养不良性 NOS阳性神经突 (DTN) ;15～ 16月龄 app/ ps1dtg小鼠皮质和海马内NP的体积分别是 4～ 5月龄 app/ ps1dtg小鼠皮质 NP的 5倍 (P<0 .0 0 5 )和 8倍 (P<0 .0 0 1) ;15～ 16月龄 app/ ps1dtg小鼠皮质内 DTN的体积明显增大 (P<0 .0 1) ;且伴有 NOS阳性神经元形态的改变及海马 CA1 区 NOS阳性神经元数量的减少 (P<0 .0 5 ) ,DTN的形成与 NP呈正相关关系 (r=0 .85 ,P<0 .0 5 )。本实验结果表明 ,app/ ps1dtg小鼠能够模拟 AD患者脑内 NOS阳性神经元的病理改变 ,DTN的形成可能与 Aβ的毒性作用有关 ,DTN产生的 NO可能参与 app/ ps1dtg小鼠和 AD的神经病理过程。     

Crystalline morphology of block-copoly(oxypropylene/oxyethylene/oxypropylene) by small-angle X-ray and Raman scattering

Block-copoly(oxypropylene/oxyethylene/oxypropylene)s, with central-block lengths of 39 and 75 oxyethylene units and end-block lengths in the range 1 to 13 oxypropylene units, were investigated in their solid states by small-angle X-ray diffraction and low-frequency Raman spectroscopy, supplemented by differential scanning calorimetry. Low-frequency Raman transitions were assigned to longitudinal modes (LAM) of either unfolded or once-folded chains. The solid state comprised stacked monolayer lamellae in which the chains were usually tilted with respect to the lamellar end plane.     

猕猴输精管内注射高分子聚合物HFMC后对睾丸组织结构的影响

本实验选用具有生育力成年雄性猕猴７只，在直视下行双侧ＨＦＭＣ输精管内注射，每侧剂量分别为３０ｍｇ１只，６０ｍｇ和１００ｍｇ各３只；于注射后２．５年和３．５年分别处死动物，取睾丸组织进行光镜和电镜观察．结果发现：猕猴注射ＨＦＭＣ２．５年后，睾丸光镜大部分曲细精管生精上皮结构完整，排列整齐。仅见局部少数管腔生精上皮层数减少，上皮细胞轻度水样变性等病理改变。电镜下曲细精管内除支持细胞内脂褐素增多，轻度基底膜增厚和精母细胞内质网扩张外，各级生精细胞，支持细胞及细胞间连接复合体等超微结构未见明显异常。注射ＨＦＭＣ３．５年后猕猴的光镜、电镜结果与注射后２．５年结果相似，但局部改变较２．５年组轻。上述结果表明：猕猴输精管内注射一定剂量ＨＦＭＣ节育不会引起睾丸组织的严重病理改变。但是，由于注射ＨＦＭＣ后，ＨＦＭＣ释放Ｈ＋及其对输精管的暂时阻塞，改变了精子生存的内环境，使睾丸出现局部轻度病理改变，随着ＨＦＭＣ逐渐溶解排出，睾丸功能相继恢复正常，配对产仔。为ＨＦＭＣ应用提供了安全性依据。     

缺血性股骨头坏死患者血清透明质酸及层粘连蛋白的研究

为探讨细胞外间质主要成分透明质酸（ＨＡ）与层粘连蛋白（ＬＮ）在缺血性股骨头坏死（ＩＮＦＨ）中的生理病理过程及临床价值，采用放射免疫分析法对４５例不同病因的ＩＮＦＨ患者进行了血清ＨＡ与ＬＮ的定量分析，并与３０例正常人对照。结果显示，ＩＮＦＨ患者血清ＨＡ含量极显著地高于对照组（ｔ＝３－２９；Ｐ＜０－０１）。尤以激素性ＩＮＦＮ增高最为显著（ｔ＝３－６２；Ｐ＜０－０１）。ＩＮＦＨ患者ＬＮ含量亦明显高于对照组（ｔ＝２－８４；Ｐ＜０－０１）。同时，ＨＡ与ＬＮ含量增高与病程发展密切相关。故定量检测ＨＡ与ＬＮ可作为ＩＮＦＨ早期诊断及判断预后的良好指标     

人FascDNA的克隆及其在大肠杆菌中表达的研究

为获得高质量及充足的Ｆａｓ蛋白，采用ＰＣＲ技术调整Ｆａｓ基因的开放阅读框架，使之与生物素化蛋白基因阅读框架一致；缺失了ＦａｓｃＤＮＡ基因的起始密码子并增加一个大肠杆菌偏性终止密码子，构建ＦａｓｃＤＮＡ和生物素化融合原核表达质粒ＰｉｎＰｏｉｎｔ－Ｆａｓ。将重组质粒转入大肠杆菌ＨＢ１０１，经５００ｍｍｏｌＩＰＴＧ在３７℃条件下诱导４ｈ，ＳＤＳ－ＰＡＧＥ及Ｗｅｓｔｅｒｎ印迹检测融合蛋白在大肠杆菌得以高效表达，表达量为细菌总蛋白的１３．８％。用亲和层析树脂对生物素化融合蛋白进行亲和层析纯化，得到Ｆａｓ重组的蛋白，且表达的Ｆａｓ融合蛋白具有抗体结合活性。此蛋白的表达成功将解决Ｆａｓ膜蛋白不易提取的难题，为深入研究Ｆａｓ提供了良好材料来源     

Direct in vivo protein transduction into a specific restricted brain area in rats

Attempts at protein transduction into specific restricted brain areas have remained unsuccessful. We attempted targeted, direct in vivo protein transduction by microinjecting beta-galactosidase (beta-gal) with hemagglutinating virus of Japan envelope (HVJ-E) vector into the rat nucleus tractus solitarius (NTS). The medulla oblongata including the NTS was removed 6h post-injection and cryostat sections were histochemically stained to detect beta-gal enzymatic activity. beta-gal-positive cells were present in these sections as was beta-gal activity determined by colorimetric analysis. beta-gal-positive cells were not present in the rats microinjected only beta-gal protein without HVJ-E vector. Our findings suggest that direct in vivo protein transduction into specific restricted brain areas is possible. The type of targeted delivery system we present may have wide applications in the administration of therapeutic proteins to the central nervous system.     

心室晚电位的时间－频率表示法的进一步改进

在心室晚电位的研究中，我们引入了信号的时间一频率表示法，并根据晚电位的具体特性用Ｗｉｇｎｅｒ分布法（维格纳分布）把信号表示为在时间及频率空间中的能量分布。由于Ｗｉｇｎｅｒ分布的优异性质使我们有可能更准确表示出心室晚电位的存在。但当输入信号是两个信号的线性叠加时，Ｗｉｇｎｅｒ分布的结果会出现一个交叉项，相当于引入干扰。针对此不足，作者介绍改进方案，消除部分交叉项，收到较好的效果，并给出一些仿真及应用实例。     

Myopodin, a synaptopodin homologue, is frequently deleted in invasive prostate cancers.

Prostate cancer is one of the leading causes of cancer-related deaths for men in the United States. Like other malignancies, prostate cancer is underscored by a variety of aberrant genetic alterations during its development. Although loss of heterozygosity or allelic loss is frequently identified among prostate cancers, few genes have been identified thus far as critical to the development of invasive prostate cancers. In this report, we used the recently developed technology, the "differential subtraction chain," to perform a genome-wide search for sequences that are deleted in an aggressive prostate cancer. Among the deleted sequences, we found that one sequence was deleted in >50% of prostate cancers we tested. We mapped this sequence to chromosome 4q25 by screening the Genebridge 4 hamster radiation panel with primers specific to this probe, and subsequently identify a 54-kb minimal common deletion region that contains the sequence encoding myopodin. Sequence analysis indicates that myopodin shares significant homology with synaptopodin, a protein closely associated with podocyte and neuron differentiation. Further study shows that frequent complete or partial deletions of the myopodin gene occurred among invasive prostate cancer cases (25 of 31 cases, or 80%). Statistical analysis indicates that deletion of myopodin is highly correlated with the invasiveness of prostate cancers, and thus may hold promise as an important prognostic marker for prostate cancers.     

Acidic ATP activates lymphocyte outwardly rectifying chloride channels via a novel pathway

Using whole-cell patch-clamp techniques we found that ATP activated an outwardly rectifying current in Daudi human B lymphoma cells under acidic conditions. The substitution of Cl^– for gluconate^– shifted the reversal potential, while Cl^– channel blockers, 4,4-diisothiocyanostibene-2,2-disulfonic acid (DIDS) and 9-anthracene carboxylic acid (9-AC), blocked the current, indicating that ATP induces this current by activating the outwardly rectifying chloride channel (ORCC). The effect of ATP on ORCC was mimicked by ADP, but not by other P2 receptor agonists such as ATPS (a poorly hydrolyzable analog of ATP), 2,3-O-benzoyl-4-benzoyl-ATP (BzATP), and UTP. The ATP-induced ORCC current was completely blocked by 100 M suramin (a P2 receptor antagonist), and was partially blocked by 100 M pyridoxal-phosphate-6-azophenyl-2,4-disulfonic acid tetrasodium (PPADS), which is another P2 receptor antagonist. Neither inactivation of G proteins nor elimination of extracellular Ca²⁺ affected the ATP-induced current, indicating that G protein-coupled P2Y receptors and Ca²⁺-permeable P2X receptors are not involved. Based on the pharmacological profile and the fact that acidic conditions are required for ATP to activate the ORCC, we suggest that acidic ATP activates the lymphocyte ORCC via a novel pathway, which is not associated with any previously described purinergic receptors.