急性脑血管病患者血清髓鞘碱性蛋白含量研究

用酶联免疫吸附法对３０例急性脑血管病（ＣＶＤ）患者及３２位正常人血清髓鞘碱性蛋白（ＭＢＰ）含量进行检测。结果表明：急性ＣＶＤ组患者血清ＭＢＰ含量显著高于正常人组（Ｐ＜０．０１）；血清ＭＢＰ含量与急性ＣＶＤ的严重程度相关。提示检测血清ＭＢＰ含量对急性ＣＶＤ诊断及预后判断有重要价值     

Age-related Changes in Bovine α-crystallin and High-molecular-weight Protein

The high-molecular-weight (HMW) protein from the lens is composed mostly of α-crystallin in a highly aggregated state. Bovine HMW protein was carefully separated from α-crystallin by size-exclusion chromatography. α-Crystallin has chaperone-like ability whereby it stabilizes other proteins under conditions of stress (e.g. heat). Comparison of bovine HMW protein and α-crystallin shows that the HMW protein has a markedly reduced chaperone ability compared to α-crystallin. However, in contrast to the results of other workers, we observe no alteration with age in the ability of α-crystallin to act as a chaperone. Using electrospray ionisation mass spectrometry, changes in the phosphorylation of the α-crystallin subunits with age have been quantified. Phosphorylation of α-crystallin occurs early in life but does not alter in proportion after about three years of age. In addition, phosphorylation of the A subunit of α-crystallin has little effect on its chaperone ability. As is found in the artificially prepared HMW complex of α- and γ-crystallin, NMR spectroscopy shows that in the naturally occurring HMW protein, the short C-terminal extension of the α_Bsubunit has lost its flexibility whereas the α_Asubunit extension is still flexible. Post-translational modifications therefore seem to have little effect on the chaperone action of α-crystallin, but alterations in the quaternary structure of α-crystallin via incorporation into the HMW aggregate, lead to major changes in the chaperone ability of the protein. The results are consistent with the notion that one of the contributing factors to cataract formation in the lens is the depletion of α-crystallin with age as it is converted into the HMW protein.     

Ubiquitin and heat shock protein expression in amyotrophic lateral sclerosis

The expression of two heat shock proteins, HSP72 and p57, in addition to ubiquitin, has been studied immunocytochemically in nine amyotrophic lateral sclerosis (ALS) cases and 10 age-matched controls. HSP72 and p57 antibodies did not identify the characteristic ubiquitin-immunoreactive inclusions present in anterior horn cells in ALS spinal cord. Antibodies to HSP72, but not to p57 or ubiquitin, strongly labelled structures corresponding to polyglucosan bodies in spinal grey matter. Such immunoreactive profiles were more abundant in ALS cases, although they were also present in control material. They were sometimes identified by haematoxylin and eosin and periodic acid Schiff reaction, but were not labeled by phosphotungstic acid haematoxylin or by antibodies to glial fibrillary acidic protein. Although ubiquitin, HSP72 and p57 are stress-induced proteins, they are expressed differently and might therefore have different significance in neuronal degeneration.     

胞嘧啶脱氨酶的原核表达和多克隆抗体的制备

目的：在原核系统中表达并纯化大肠杆菌胞嘧啶脱氨酶（cytosine deaminase,CD)，制备鼠抗大肠杆菌CD多克隆抗体，方法：亚克隆CD基因到原核表达载体pMAL-c2和pBV222中，并转化入大肠杆菌DH5α内，诱导表达并纯化MBP-CD和6his-CD融合蛋白，用纯化的MBP-CD融合蛋白免疫小鼠制备多克隆抗体。结果：通过重组质粒的酶切筛选出重组阳性克隆，成功地表达和纯化出MBP-CD和6his-CD融合蛋白，用纯化的MBP-CD成功制备了鼠抗CD多克隆抗体，并用6his-CD和GST-CD重组蛋白进行Western印迹分析，证实了抗体的正确性，结论：应用多克隆抗体可以检测体内外CD基因的表达，为临床前和临床上深入开展CD基因的生物治疗研究提供重要的实验材料。