Human mini-chromosomes in mouse embryonal stem cells

We have introduced human mini-chromosomes of 4 Mb and approximately 15 Mb in size into mouse embryonal stem cells. Although these human mini- chromosomes are stable in hamster and chicken cells, they re-arrange or segregate aberrantly in the embryonal stem cells and are rapidly lost in the absence of selection. However, one of the mini-chromosomes re- arranged, acquired mouse centromeric sequences and was then stably maintained for at least 60 population doublings in culture. This mini- chromosome, which is 4 Mb in size, is a candidate for a mouse germ line chromosome vector.      

脑内源性β-内啡肽对应激诱发促肾上腺皮质激素和催乳素释放的调节

在预先埋植第三脑室导管和预置颈外静脉导管的SD大鼠中,脑室内微量注射β-内啡肽抗血清,并与脑室内注射正常兔血清的大鼠对比。看到注射β-内啡肽抗血清后,ACTH和催乳素因限制性应激的释放,分别被抑制了46.1％和71.2％。说明中枢内源性β-内啡肽可能是ACTH和催乳素在某种应激时相伴释放的重要调节因素之一。     

不同导联系统记录体表心室碎裂电位效果对比研究

本文分别应用标准１２导联系统，Ｆｒａｎｋ正交导联系统和改良Ｆｒａｎｋ正交导联系统记录健康人３６例、陈旧性心肌梗塞４２例的心室碎裂电位，通过分析这些导联系统中相互垂直或近似垂直的导联上ＶＦＰ的形态，数量关系，发现改良Ｆｒａｎｋ正导联系统记录ＶＦＰ较其它导联系统更科学，合理，且操作方便。     

CM1 ligation initiates apoptosis in a caspase 8-dependent manner in Ramos cells and in a mitochondria-controlled manner in Raji cells

Burkitt lymphoma (BL) is a tumor with the characteristics of germinal center B cells. We previously reported that the CM1 (centrocyte/-blast marker 1) molecule is expressed only in germinal center B cells, specifically, in a subpopulation of centroblasts and centrocytes. In the present study, we investigated the apoptosis induced by anti-CM1 in the Ramos and Raji human BL cell lines. The Ramos is protected from apoptosis by the crosslinking of sIgM and the calcium ionophore by the ligation of CD40 with anti-CD40 monoclonal antibodies (mAb) or soluble CD40 ligand (sCD40L). In this investigation on the effect of CM1 on apoptosis in BL cell lines, we found that cellular signaling by CM1 induces apoptosis and decreases cell viability, in BL cell lines cultured for 24 hours with protein-G agarose beads conjugated anti-CM1 mAb. Stimulation by CD40 ligated with sCD40L protected Raji cells from CM1-induced apoptosis, but did not protect Ramos cells. Furthermore, after anti-CM1 mAb stimulation, CD95 expression was upregulated and CD40 expression was unaltered or slightly decreased in Ramos cells, whereas CD95 was downregulated and CD40 was slightly upregulated in Raji cells. The engagement of CD40 by sCD40L enhanced CD95 expression, but the level of CM1 expression was unchanged in Ramos. However, sCD40L downregulated both CD95 and CM1 expression in Raji. In addition, the caspase-8 specific inhibitor blocked CM1-induced apoptosis in Ramos cells, but not in Raji cells. Increased mitochondrial membrane permeabilization was observed only in Raji cells. Moreover, the effector caspase inhibitor, z-DEVD, blocked CM1-mediated apoptosis in both cell lines. We found that CM1-induced apoptosis is achieved via different initiation pathways, which are cell-type dependent.     

痘苗病毒VGF细胞膜外结构域在真核及原核细胞中的表达

目的为了进一步探索ＶＧＦ的生物学功能方法分别构建了痘苗病毒天坛株生长因子（Ｖａｃｃｉｎｉａｇｒｏｗｔｈｆａｃｔｏｒ，ＶＧＦ）基因细胞膜外结构域（ＶＧＦｓｌ）的真核及原核表达系统，在相应的细胞中获得了单独表达（真核）和融合表达（原核）。结果初步纯化的ＶＧＦｓｌ表达产物能够与上皮生长因子（ＥＧＦ）的受体结合，并刺激受体中酪氨酸残基发生磷酸化反应。与ＥＧＦ相比，ＶＧＦｓｌ表达产物刺激ＥＧＦ受体自身磷酸化的能力更强。结论上述结果为ＶＧＦ在病毒感染过程中的作用以及ＶＧＦ作为新型多肽类药物的研究提供了有价值的线索。     

Bilateral retinal responses after lens disruption in rabbits with and without skin graft

In the rabbit, lens disruption produced very little histological changes in the retina. However, lens disruption after skin graft produced an alarming picture with infiltration of inflammatory cells and degeneration of retinal layers.     

Altered p53 expression in Epstein Barr virus positive T cell lymphomas.

Recent studies have suggested a probable association between Epstein-Barr virus (EBV) and nasal/nasopharyngeal T cell lymphomas but the role of oncogenes or tumor suppressor genes is poorly understood. We have studied the frequency of p53 expression and its relation to the EBV infection in 33 Korean patients with head and neck (H&N) lymphomas. All cases (23 B cell & 10 T cell) were immunostained for p53 protein using the mAb D07 (Novocastra) and the avidin biotin peroxidase method. EBER in situ hybridization was performed using a fluorescein conjugated EBV oligonucleotide probe (Dako). Among 33 lymphomas, 16 cases stained positively for p53 protein. P53 expression was frequent both in higher grade lymphomas and in advanced stage. Nine cases were EBER positive, EBER was more commonly found in T cell lymphomas than in B cell lymphomas (70% vs 8.7%). EBER positive lymphomas showed a higher frequency of p53 positivity than EBER negative lymphomas (78% vs 38%), although the difference was not statistically significant (p = 0.095). These findings indicate altered expression of p53 protein occurs in H&N lymphomas, especially in late event lymphoma progression and appears to play a role in the development of EBER positive T cell lymphomas.     

弓形虫分离株表膜脂肪酸的色质谱分析

本文采用有机质谱法（ＧＣ／ＭＳ）对弓形虫不同分离株，虫体表膜脂肪酸的种类和含量进行观察分析，实验结果表明弓形虫速殖子细胞膜含有６种主要脂肪酸，范围在Ｃ１４－Ｃ１８之间，分别为肉豆寇酸、棕榈油酸、软脂酸、硬脂酸、油酸和亚油酸，而油酸和软脂酸约占总脂肪酸含量的７０％（５２－８４％）。本室自畸胎儿分离获得的ＳＨ多个虫株的脂肪酸含量及组分与国际标准人源ＲＨ株相一致，而ＳＨ４，ＳＨ（１０）与ＰＰ株，ＲＴ株相似，与平行观察的人和哺乳动物细胞膜的脂肪酸在含量与组分上均有明显差异，为鉴定分离的弓形虫株提供了实验依据。     

Family-based association study between autism and glutamate receptor 6 gene in Chinese Han trios.

The glutamate pathways are involved in diverse processes such as learning and memory, epilepsy, and they play important roles in neural plasticity, neural development, and neurodegeneration. It has been proposed that autism could be a hypoglutamatergic disorder. Recently, Jamain et al. reported that the glutamate receptor 6 (GluR6 or GRIK2) is in linkage disequilibrium with autism. In the present study, the transmission disequilibrium test (TDT) and the haplotype transmission were performed to analyze the four SNPs (SNP1: rs995640; SNP2: rs2227281; SNP3: rs2227283; SNP4: rs2235076) of GluR6 in 174 Chinese Han parent-offspring trios. The TDT demonstrated that the two SNPs (SNP2 and SNP3) showed preferential transmission (TDT P = 0.032). The global chi(2) test for haplotype transmission also revealed an association between GluR6 and autism (chi(2) = 10.78, df = 3, P = 0.013). Our results suggested that GluR6 is in linkage disequilibrium with autism.