Co-localization of vasoactive intestinal polypeptide, γ-aminobutyric acid and choline acetyltransferase in neocortical interneurons of the adult rat

Interneurons immunoreactive for vasoactive intestinal polypeptide (VIP) are integral elements of columnar organization patterns in the rat cerebral cortex. By application of the sensitive mirror technique, the co-localization of VIP with the classical inhibitory neurotransmitter γ-aminobutyric acid (GABA) and the acetylcholine-synthesizing enzyme, choline acetyltransferase (ChAT), was investigated in neocortical neurons. Furthermore, the frequency of co-localization of ChAT with GABA was determined. In a sample of 118 VIP-immunoreactive neurons, mostly from the primary somatosensory cortex, it was demonstrated that virtually all of them reveal immunoreactivity for GABA and, therefore, are to be GABAergic. Moreover, 34% of mostly bipolar, VIP-positive neurons contained ChAT and are, thus, supposedly cholinergic as well. Co-localization of VIP and ChAT varied according to cortical laminae. Finally, 88% of a total of 60 ChAT-immunoreactive neurons were also immunostained for GABA. It is concluded that almost all VIP-immunoreactive neurons and most of the cholinergic neurons in rat neocortex represent partly overlapping subpopulations of inhibitory interneurons utilizing GABA.     

X-Ray Study of the Cat Hindlimb During Treadmill Locomotion

With pulsed X-ray cinematography we have analysed the angular excursions of the distal hindlimb joints (proximal interphalangeal, PIP; metatarsophalangeal, MTP; ankle) in cats walking on a treadmill. These distal joints transmit the body weight and the dynamic forces onto the ground. We have included the knee and hip joints in the analysis to relate the angular excursions of the proximal and distal joints and to verify the data previously obtained with external markers on the kinematics of the proximal joints. At the beginning of the stance phase the PIP joints flexed rapidly, the MTP joints extended slowly and the ankle and knee yielded under body weight. Whereas the PIP joints maintained a rather constant angular position of −75° throughout the stance phase, extension continued in the MTP joints from −230° at touch-down to −270° at the end of the stance phase. Around 50 ms before lift-off the MTP joints flexed rapidly. Early (−30 ms) after lift-off this flexion changed into a slow extension. The PIP joints extended swiftly at the stance-swing transition and moderately at the end of the swing phase. During the middle part of the swing phase they flexed slowly. Small rotatory movements around the long axis of the foot took place in the last 100 ms of the swing phase. The results of this study on the distal joints are discussed in relation to the placing of the paw, to the translation of forward propulsion into a MTP movement and to the lifting of the paw (conventionally described as toe curling). They show a differentiated mechanical interaction between the different distal limb joints during these different phases, which must be known in detail to interpret the corresponding electromyographic data and to understand how the hip is moved forward over the MTP joints which serve as the final pivot during stance.     

nm23-H1基因转染对人胆管癌细胞系QBC939体外浸润能力的影响

目的：探讨nm23-H1基因转染对人胆管癌细胞系QBC939体外浸润能力的影响。方法：将含有全长nm23-H1 cDNA的真核表达载体通过脂腩体法转染人胆管癌细胞系。结果：转染成功的QBC939细胞，其nm23-Hl基因的mRNA、蛋白表达明显增加，转染nm23-H1基因的胆管癌细胞体外浸润能力下降，穿越matrigel的细胞数明显低于亲本QBC939细胞，代表浸润能力的IV型胶原酶（MMP-9）分泌量下降。结论：nm23-Hl基因可以抑制胆管癌细胞的体外浸润能力。     

中国汉坦病毒H82O5株G2糖蛋白基因的克隆及在真核细胞中的瞬时表达

从感染病毒乳鼠脑组织提取总RNA，采用RT－PCR和分子克隆技术将扩增到的G2糖蛋白基因插入含CMV启动子的pcDNA3.1/His质粒载体中，通过脂质体介导转染COS－7细胞，用SDS－PAGE、Western-blot及IFIA方法分别测定表达产物的相对分子量及特异性。结果证明获得正向插入的G2－pcDNA3.1/His重组表达质粒，表达产物的相对分子量为56ku，与理论预期大小一致，并且可与汉坦病毒H8205株的腹水抗体起特异反应。表明构建的G2－pcDNA3.1/His重组质粒所表达的蛋白为中国汉坦病毒株特有，能在哺乳动物细胞中表达并具有抗原性，重组质粒可应用于汉坦病毒的DNA疫苗研究。     

白血病细胞p16基因突变分析

目的探讨ｐ１６基因突变在白血病发生中的作用及基因突变的机制。方法利用点突变检测仪、水平和垂直板电泳对ｐ１６基因的外显子１、外显子２的ＰＣＲ扩增产物作缺失和点突变分析。结果在白血病３５例临床标本中有２２例发生缺失突变，６例发生点突变，突变率约８０％。在２２例缺失突变病例中，有１０例为不完全缺失突变即有低于外显子５０９ｂｐ的扩增产物。结论ｐ１６基因含有“ＧＣ”ＤＮＡ重复顺序，易发生ＤＮＡ重组及易位和重排。在白血病发生中起重要作用     

人睫状神经营养因子结构和功能的研究

制备高活性的重组人睫状神经营养因子，并研究其生物学功能。方法：应用大肠杆菌表达ｈＣＮＴＦ，用片段插入和法研究其结构与功能关系；切断大鼠骨神经，局部及皮下给予ＣＮＴＦ，应用辣根过氧化物酶逆行追踪技术显示再生轴突通过修复部位的胞体。结果；ｈＣＮＴＦ分子中α－螺旋结构的维持对其生物活性十分重要Ｃ端松散地其生物活性贡献不大，Ｄ螺旋中后段可能与生物活性有密切关系；     

Etiological heterogeneity in Hodgkin's disease: HLA linked and unlinked determinants of susceptibility independent of histological concordance

Forty-one multiplex families, from published sources and new data from the National Cancer Institute, segregating for Hodgkin's disease and HLA, have been studied. A reanalysis of these data strongly suggests a recessive mode of inheritance for susceptibility to Hodgkin's disease. The HLA haplotype sharing data between affected relatives demonstrate that approximately 60% of cases in multiplex families are due to an HLA-linked susceptibility gene, the remaining 40% being due to other familial factors. The data clearly support the hypothesis of etiological heterogeneity for Hodgkin's disease, with both HLA-linked and HLA-unlinked factors being responsible. Finally, there is an increased concordance of histological types between affected relatives, but this concordance seems independent of HLA sharing.     

60Co辐照血红细胞CR1分子数目的变化

目的研究不同剂量60Co γ射线辐照全血在保存期内红细胞CR1分子数目的变化.方法应用酶联法定量测定经15～35GY五个照射剂量辐照全血在保存期内红细胞CR1分子数目.结果照射后1d,15～25GY剂量组红细胞CR1分子数目相互间比较及分别与对照组比较无明显差异(P＞0.05);经30、35GY辐照红细胞CR1分子数目分别与其他剂量组和对照组比较有明显差异(P＜0.05～0.01).另外,随着保存期的延长,各剂量组和对照组红细胞CR1分子数目呈阶梯式下降,尤其在照射后3d,30和35GY剂量组红细胞CR1分子数目接近于照射后7d水平,二者相互比较无明显差异(P＞0.05).结论在一定范围内(15～25GY)60Co γ射线剂量辐照对红细胞CR1分子数目无明显影响.     

Agilent 2100 Bioanalyzer在基因差异表达研究中的应用

目的观察Agilent 2100 Bioanalyzer 芯片分析系统(以下简称Bioanalyzer)在基因差异表达研究中的应用。方法应用限制性显示技术分别从正常和热休克处理后的酿酒酵母细胞中分离出cDNA片段,然后再用Bioanalyzer和传统的琼脂糖凝胶电泳技术对RD-PCR产物进行检测分析。结果Bioanalyzer能更快速、敏感地分离和显示差异表达的基因片段,并且通过对差异片段进行定量比较,发现了数个表达有明显差异的基因片段。结论Bioanalyzer在基因差异表达研究中具有重要的应用价值。     

Screening Mouse Genes Related to Blastocyst Implantation by Using PCR Subtraction

Objective To identify genes that may be related to embryo implantation Materials & Methods The PCR subtraction technique was applied at implantation and inter-plantation sites on day 4. 5 of pregnancy in mice. Two novel Expressed Sequence Tags (ESTs ), EST8 and EST81 were identified; their expression in tissues was analyzed by Northern blotting, and their full-length cDNAs were synthesized by PCR.Results We found that these two novel ESTs (EST8and EST81) were noticeably expressed in implantation site in the mouse on day 4. 5 of pregnancy. EST8 was expressed at high level in livers and implantation sites of the mice, while at low level in ovaries and inter-plantation sites. EST81 was predominantly expressed in implantation site and ovary, and at low level in all other tissues. Their complete cDNAs, 1 665bp and 1 264 bp respectively, were synthesized by using PCR.Conclusion The two full-length cDNAs were responsible for embryo implantation,and their functions need to be further studied.