外源性生长激素对改善腹腔感染时生长激素不敏感状态中的作用

探索了外源性生长激素对改善腹腔感染时生长激素不敏感中的作用。应用盲肠结扎穿孔法（CLP）制备腹腔感染大鼠模型,同时给予外源性生长激素;应用放射免疫法测定血清生长激素（GH）水平;应用逆转录多聚酶链反应（RT-PCR）法测定肝组织胰岛素样生长因子I(IGF-I)、生长激素受体（GHR）和细胞因子信号传导抑制体3(SOCS-3)mRNA的表达;应用ELISA测定血清肿瘤坏死因子α(TNF-α)和白介素6(IL-6)水平。结果表明腹腔感染组大鼠血清生长激素水平与对照组无明显差异,但肝组织IGF-ImRNA表达明显下降;给予外源性生长激素后可明显降低血清TNF-α和IL-6水平,同时可更快地促使GHR和IGF-ImRNA表达的上调及下调SOCS-3mRNA的表达。腹腔感染时机体存在对生长激素的不敏感状态,给予外源性生长激素后可明显地改善感染状态下机体对生长激素的敏感性。     

抗KDR-Fc杂交瘤细胞系的建立

用杂交瘤技术建立抗KDRFc的杂交瘤细胞系,以KDRFc抗原免疫雌性BALB/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞融合,经ELISA间接法检测和有限稀释法克隆培养,再经稳定性检测、效价检测,筛选出分泌抗KDRFc单克隆抗体的杂交瘤细胞.得到了10株能持续分泌抗KDRFc的单克隆抗体的细胞株,其中3株分泌的单抗具有较高的生物活性、特异性和稳定性.     

受体缺乏改变小鼠脑内组胺含量及昼夜节律

在乙谜麻醉下,分别于明时(8:00 a.m.)及暗时(8:00 p.m.)断头处死野生型及组胺H1R基因敲除型小鼠,迅速取出脑组织并分离出皮层、纹状体、海马、下丘脑、丘脑、中脑及脑干等脑区.这些脑组织被制成匀浆并用HPLC荧光检测法测量其组胺含量.结果显示暗时处死时,H1R基因敲除型小鼠海马、丘脑、中脑及脑干中的组胺含量明显低于野生型小鼠.明时处死时,野生型小鼠各脑区组胺含量均较暗时处死显著降低,但这一变化在H1R基因敲除型小鼠中并未观察到.这些表明作为组胺的功能靶,H1R不仅介导组胺的功能,而且调节大脑中组胺含量与释放的昼夜节律.     

Stochastic resonance in the growth of a tumor induced by correlated noises

Since half a century ago, nonlinear physics has changed our views of world drastically[1]. People expected to use it to solve the complexity of biology[2,3]. In the past decade, more and more evidence shows that noise plays an impor- tant role in nonlinear systems[4―10], such as noise-induced phase transitions, stochastic resonance (SR) and so on. Especially, SR uncovered a heap of complexities of biol- ogy[11,12]. For many years, the law of tumors growth has been a challenging subject. Sci…     

SARS病毒复制酶蛋白nsp7-nsp8十六聚体超复合物晶体结构解析

细胞浆内的β抑制因子可选择性与G蛋白偶联受体结合，并抑制受体作用。但中科院上海生命科学研究院生物化学与细胞生物学研究所裴钢研究小组与复旦大学上海医学院马兰研究小组发现，其还具有将信息直接传人细胞核的功能。研究人员实验观察到阿片类药物和细胞膜上δ阿片受体（G蛋白偶联受体家族的一个成员）结合后能促使β抑制因子从细胞浆快速迁移到细胞核内。并通过进一步研究，     

肝再生

肝脏在受到损害或切除之后,可以显示出强大的再生能力。肝再生这一现象早已被人们发现并研究。肝脏再生的启动因素有哪些,又是如何适时终止的?在肝再生过程中,哪些基因的表达发生了变化?哪些信号通路参与了肝再生过程?这些问题一直是研究者关注的焦点。本文将对肝再生研究的这些热点问题进行综述。     

Construction and anti-tumor effects of recombinant fowlpox virus expressing Newcastle disease virus hemagglutinin-neuramidinase gene

Hemagglutinin-neuramidinase (HN), a Newcastle disease virus-derived protein, not only mediates receptor recognition but also possesses neuraminidase (NA) activity, the ability to cleave a component of those receptors, N-acetylneuraminic acid (NAcneu, sialic acid). It is known that this protein in mammalian species, including human beings, has interesting anti-neoplastic as well as immune stimulating properties. To explore the use of the HN gene in cancer gene therapy, we constructed a recombi-nant fowlpox virus expressing the HN protein (vFV-HN) and compared the anti-tumor activity of the recombinant virus with that of wild-type fowlpox virus (FPV) in vivo and in vitro. Here we found that although B16 cells were somewhat resistant to the basal cytotoxic effect of wild-type fowlpox virus, infection with vFV-HN caused a pronounced cytotoxic effect and, the survival of tumor-bearing mice immunized with vFV-HN was significantly increased compared with the survival of mice immunized with the FPV alone. Furthermore, the immunization of mice with vFV-HN elicited a B16 tumor-specific cytotoxic T lymphocyte (CTL) response and clonal expansion of both CD4 and CD8 T cell populations in vivo. In addition, T cells from lymph nodes of mice vaccinated with vFV-HN secreted high levels of the Th1 cytokine IL-2 and IFN-γ, indicating that the regression of tumor cells is related to a Th1-type dominant immune response. These results demonstrate that vaccination with vFV-HN may be a potential strategy for cancer gene therapy.     

锌铝水滑石的香豆素-3-甲酸和9-蒽甲酸共插层

以层状锌铝水滑石为主体，乙二醇为分散介质，通过离子交换法，成功地将一对具有给体-受体性质的生色团香豆素-3-甲酸(3-CCA)与9-蒽甲酸(9-ACA)共插入到层状锌铝水滑石层间。采用XRD、IR、TG-DTA等测试技术对共插层产物进行了结构表征，采用UV-visible吸收光谱和荧光光谱研究了产物的光谱特性。结果表明，由于给体-受体进入层间，不仅客体与主体层板存在静电力和氢键相互作用，而且在限域空间内存在客体之间的相互作用，从而产生了给体-受体间的能量转移。     

小肽融合蛋白通过阻断VEGF与KDR结合抑制血管生成与肿瘤生长

血管内皮细胞生长因子（VEGF）结合酪氨酸激酶受体KDR／FLK1能促进血管生成。筛选能封闭VEGF与KDR相互作用的小肽可以通过阻断血管形成而抑制实体瘤生长。将从噬菌体12肽库中筛选而获得的能与KDR结合的123肽K237DNA克隆到表达载体p QE42中，在大肠杆菌M15中稳定表达二氢叶酸还原酶融合蛋白DHFJR－K237，经变性、复性后得到纯度达90％的可溶性蛋白。体外实验显示，DHFR－K237能竞争抑制VEGF结合KDR，显著抑制由VEGF刺激而引起的人脐静脉内皮细胞增殖；体内实验表明，DHFR－K237能显著抑制鸡胚尿囊膜血管形成和荷瘤裸鼠中肿瘤的生长。结果表明，12肽K237是VEGF结合KDR的有效拮抗剂，具有抗肿瘤生长和转移的潜在应用前景。