龙马酶的固定化研究

研究龙马酶（ＥＣ ３． １． １． ３）固定化载体、固定化条件和固定化酶的性质。方法：固定化采用吸附法。结果：固定化最适条件：酶液ＰＨ９．０,吸附时间１．５ ｈ,酶浓度１．５ ｇ／１００ ｍｌ,在此条件下固定化酶活力５３ ｕ／ｇ载体,活力回收率７１％。固定化酶的最适作用温度和ｐＨ较游离酶高,范围较游离酶广,耐热性、酸碱稳定性比游离酶好。结论：固定化酶性能比游离酶得到提高。     

表达重组人红细胞生成素细胞株的高密度、高表达培养

用生物反应器培养能表达重组人红细胞生成素的工程细胞,使其达到高密度高表达。方法：先将工程细胞在含有５％胎牛血清的 ＤＭＥＭ－Ｆ１２培养基中培养,待细胞总数达到 ２×１０~８个以上时,接种到５ Ｌ生物反应器中。用含有血清的培养基培养 ７ｄ后转为无血清ＣＨＯ专用培养基,继续培养 ３０ ｄ。在整个培养过程中,采用流加的方式连续培养,根据情况随时测定培养基中葡萄糖浓度,使其保持高于０．５ｇ／Ｌ,同时监测氨及乳酸盐浓度,避免浓度过高。每日采样测定收获液中红细胞生成素含量与活性,培养结束后,以０．２５％胰酶消化载体,待细胞全部脱落后计数细胞总量。 结果：细胞密度达 ６×１０~６个／ｍｌ培养液,表达量约 ３０ ０００ ＩＵ／ｍｌ左右,且表达的红细胞生成素具有较高的生物比活性。结论：在较为适当的培养条件下,利用生物反应器可使工程细胞的培养达到高密度、高表达。     

Low prevalence of the APC I1307K sequence in Jewish and non-Jewish patients with inflammatory bowel disease.

A germline sequence alteration at codon 1307 of the APC gene (I1307K) has been reported in 6-7% of the Ashkenazi Jewish population in the United States. This alteration is believed to predispose the APC gene to a secondary mutation at the same locus, resulting in an increased risk of colorectal carcinoma. There is an increased risk of colorectal carcinoma in patients with inflammatory bowel disease (IBD), a relatively large proportion of whom are Ashkenazi Jews. We therefore sought to determine whether the I1307K sequence variant occurred in the germline DNA of IBD patients. To our surprise, we found this sequence in only two of 267 patients with IBD (0.7%), occurring in only 1.5% of Jewish IBD patients. The I1307K sequence variant was not found in 67 patients with esophageal cancer, 53 patients with gastric carcinoma (13 MSI-H and 44 MSI-negative), or ten patients with sporadic MSI-H colon cancer. These findings suggest that the I1307K sequence is relatively rare in the germline of Jewish as well as non-Jewish IBD patients. It does not appear to contribute to the increased colorectal cancer risk present in these patients.     

异种抗体IgM对培养豚鼠心脏微血管内皮细胞的作用

目的:了解大鼠体内天然抗体IgM在非协调性异种心脏移植超急性排斥反应中的作用。方法:以培养豚鼠心脏微血管内皮细胞为异种心脏移植的细胞实验模型,通过补体结合实验、免疫组化等方法研究大鼠抗体IgM对该细胞的作用,了解异种抗体IgM在异种移植超急性排斥反应中的作用机制。结果:在该模型中,大鼠抗体IgM可与豚鼠心脏微血管内皮细胞结合并能激活补体,产生对该细胞的损伤,而经小鼠抗大鼠IgM处理后的大鼠血清,对豚鼠心脏微血管内皮细胞的损伤作用明显减轻。结论:在该实验模型中,异种天然抗体IgM是激活补体引起超急性排斥反应的重要因素。     

The significance of anti-endothelial cell antibodies in patients with lupus nephritis and immunoblotting analysis of the target components

ＯｂｊｅｃｔｉｖｅＴｏｉｎｖｅｓｔｉｇａｔｅｔｈｅｐｒｅｖａｌｅｎｃｅｏｆａｎｔｉｅｎｄｏｔｈｅｌｉａｌｃｅｌａｎｔｉｂｏｄｉｅｓａｎｄｉｔｓｐｏｓｓｉｂｌｅｒｏｌｅｉｎｔｈｅｐａｔｈｏｇｅｎｅｓｉｓｉｎｌｕｐｕｓｎｅｐｈｒｉｔｉｓＭｅｔｈｏｄｓ...     

用白细胞粘附抑制法鉴定HBV—TF特异免疫活性

选用白细胞粘附抑制试验来鉴定乙肝特异性转移因子(HBV-TF)免疫活性。实验结果表明:经HBV-TF致敏的淋巴细胞与乙肝抗原(HBV-Ag)孵育后,显示出明显的粘附抑制活性,而非特异性转移因子(TFn)致敏淋巴细胞与乙肝抗原孵育、HBV-TF致敏淋巴细胞与甲肝抗原(HAV-Ag)孵育或HBV-TF致敏淋巴细胞与1640液(代替抗原液)孵育时均不能表现出这种抑制作用,说明HBV-TF具有抗原特异性免疫活性。实验证明,本法是体外鉴定HBV-TF免疫活性简便易行的方法。     

人嗜酸性细胞趋化素基因cDNA的分离及序列分析

目的：分离编码人嗜酸性细胞趋化素的基因ｃＤＮＡ,并将它克隆至质粒ＰＵＣ１８中进行核苷酸序列分析。方法：采用ＴＮＦα刺激人肺上皮细胞提取总ＲＮＡ,利用ＲＴ－ＣＰＲ方法获得了ｈＥｏｔ的ＣＤＮＡ,并将其定向插入ＰＵＣ１８载体中进行核苷酸序列。结果：ＤＮＡ序列分析表明分离的ｈＥｏｔｃＤＮＡ的序列与文献报道的完全一致。结论：本研究获得了序列正确的ｈＥｏｔ基因ｃＤＮＡ,为下一步的研究打一了基础。     

内皮素及其A受体在兔颅脑创伤后脑血流量变化中的作用及意义

目的:了解内皮素(ET)及其A受体在颅脑创伤后脑血流量变化中的作用及意义.方法:130只家兔致以左额顶叶为着力部位的加速性撞击伤,动态观察脑组织内皮素含量变化、内皮素A受体mRNA表达和定位变化,内皮素A受体拮抗剂BQ123的作用及上述变化对脑血流量变化的影响.结果:脑创伤后血浆、脑脊液和局部脑组织内皮素含量显著升高;内皮素A受体mRNA主要分布于脑血管内皮细胞,表达显著增强;创伤后局部脑血流量显著降低,应用BQ123治疗的动物,血流量下降被明显抑制.结论:内皮素通过其A受体的调节在颅脑创伤后脑缺血的形成中有重要作用;应用内皮素A受体拮抗剂可以防治颅脑创伤后脑缺血.     

Affect of insulin-like growth factor I and estradiol on the growth of uterine leiomyoma]

To study roles of insulun-like growth factor 1(IGF-I) and estradiol(E2) in the growth of leiomyoma. Protein expressions of IGF-I receptor(IGF-I-R), estrogen receptor(ER), and cell proliferation associated nuclear antigen(ki-67) were analysed by streptavidin-peroxide method in 40 cases. Serum level and local concentration of IGF-I were determined by immunoradiometric assay(IRMA) in 20 cases. Serum level of estradiol was determined by radioimmunoassay in 20 cases. Twenty normal fertile women were studied as control. Protein expressions of IGF-I-R and ER in uterine leiomyoma were significantly higher than in myometrium(P < 0.05); and local concentration of IGF-I positively correlated with ki-67 (r = 0.6513, P < 0.05); and expression of estrogen receptor. The serum levels of IGF-I and E2 had no significant difference between leiomyoma patients and normal women. IGF-I and E2 promote the growth of leiomyoma and IGF-I may act as a mediator of estrogen.