Fumonisins as a possible contributory risk factor for primary liver cancer: A 3-year study of corn harvested in Haimen, China, by HPLC and ELISA

Employing HPLC fluorometry, gas-liquid chromatography (GLC) and a novel enzymelinked immunosorbent assay (ELISA) based on a monoclonal antibody, 40 corn samples, each collected in 1993 from agricultural stocks for human consumption in Haimen (Jiangsu County) and Penlai (Shandong Province), high- and low-risk areas for primary liver cancer (PLC) in China, respectively, were analysed for fumonisins (FBs), aflatoxins (AFs) and trichothecenes. Levels and positive rates of FBs and deoxynivalenol (DON) were significantly higher in Haimen than in Penlai. ELISA of the 40 corn samples harvested in the two areas in 1994 revealed that FB contamination levels and rates in these areas were comparable to those observed in 1993 in Haimen. ELISA analysis of 1993 and 1994 products revealed a wide occurrence of AFB₁ but the positive rates as well as levels were not significantly different between these areas. ELISA of the same sample number of corn harvested in 1995 revealed that FB contamination in Haimen was significantly higher than in Penlai. These 3-yearly surveys of corn samples (240 in total) demonstrated that corn harvested in Haimen was highly contaminated with FBs and that the contamination level, as well as positive rate in 1993 and 1995, were 10–50-fold higher than those in Penlai, suggesting FBs as a risk factor for promotion of PLC in endemic areas, along with the trichothecene DON. Co-contamination with AFs, potent hepatocarcinogens, was assumed to play an important role in the initiation of hepatocarcinogenesis.     

High-density lipoprotein subfractions,apolipoproteins and antipyrine clearance in normal subjects

Summary Serum high density lipoprotein (HDL) subfractions HDL₂ and HDL₃, apolipoproteins, and plasma antipyrine clearance (AP-CL) rate, an index of liver microsomal enzyme activity, were determined in 21 healthy subjects. High HDL cholesterol and HDL₂ cholesterol concentrations and HDL cholesterol/cholesterol and HDL₂/HDL₃ cholesterol ratios were associated with high AP-CL. Phenobarbital enhanced antipyrine elimination and increased the apolipoprotein A-I/A-II ratio. Subjects who had high AP-CL had a more antiatherogenic HDL subfraction and apolipoprotein profile than those with low AP-CL.     

涎腺腺癌细胞系对葫芦素BE的敏感性研究

目的 观察其有多种生物活性的葫芦素BE对涎腺腺癌细胞的杀伤作用。方法 用四唑盐显色法(MTT法)检测人腺样食性癌(ACC-M)和粘液表皮样癌(MEC-1)细胞系对葫芦素BE的敏感性实验。结果 葫芦素BE对两种腺癌细胞系均有较高的相对抗肿瘤活性(RAA值分别为345、148)。结论 实验结果为葫芦素BE治疗涎腺腺癌的进一步研究提供了重要依据。     

血清同工铁蛋白酶联免疫吸附测定及其临床观察

用酶联免疫吸附测定法(ELISA)观察了96例正常人,11例原发性肝细胞肝癌(HCC)、28例乳癌(BC)、31例肺癌(LC)、26例乳腺纤维瘤(BF)、11例肺炎(LF)及11例肺结核(TB)患者的血清同工铁蛋白(Serum isoferritin,SIF)水平。结果显示:正常人与HCC、BC、LC、BF及LF患者之间的SIF水平存在非常显著差异(P<0.01或P<0.001),在上述各类疾病中恶性肿瘤与相应组织的非癌性疾病患者之间的SIF水平也呈现非常显著的差异(BC与BF间、LC与LF间的P<0.01,LC与TB间的P<0.001)。SIF对检测HCC、LC及BC有较高的灵敏度,对鉴别这些恶性肿瘤具有重要价值。     

Ubiquitous Presence in Mammalian Cells of Enzymatic Activity Specifically Cleaving 8-Hydroxyguanine-containing DNA

Here we report the finding of enzymatic activity that specifically cleaves DNA containing 8-hydroxyguanine (oh⁸Gua) residues in various mammalian cells. To detect this activity, we used a synthetic double-stranded DNA containing a single oh⁸Gua at a defined position as the substrate, and analyzed the products of enzymatic digestion by polyacrylamide gel electrophoresis. Two cleavage sites near the oh⁸Gua residue were detected with partially purified fractions from cow brain and rat liver, and also with preparations from all mammalian tissues examined. These results suggest that enzymatic activity for the removal of oh⁸Gua from DNA is widely distributed in mammalian cells.     

多抗甲素对人NK细胞活性的作用机理研究

作者应用单细胞细胞毒试验及形态学观察，研究多抗甲素（ＰＡＡ）对人体自然杀伤（ＮＫ）细胞活性的作用机理。结果表明：ＰＡＡ能增强食道癌患者淋巴细胞（ＰＢＬ）明显低下的结合率（Ｂ％）和杀伤率（Ｋ％），也可增强正常人ＰＢＬ的Ｋ％，但对正常人ＰＢＬ的Ｂ％无影响。形态学观察发现：与靶细胞结合的ＰＢＬ除大颗粒ＰＢＬ外，尚有普通的非颗粒ＰＢＬ，结合的靶细胞损伤首先表现为线粒体肿胀、空泡变，然后核固缩，核膜损伤，细胞严重空泡变性等，偶见靶细胞与自然杀伤细胞结合部质膜破损的现象。经ＰＡＡ预处理的靶效细胞结合的形态改变无明显差异，但食道癌组的杀伤作用出现较早，且明显增强。     

Polymorphism of renin-angiotensin system genes in progressive IgA nephropathy

Summary: Clinical studies revealed that angiotensin converting enzyme (ACE) inhibitor reduces proteinuria and attenuates progressive decline in renal function in IgA nephropathy. Recent studies by us and others have demonstrated that the homozygote of the D allele (DD) of the ACE insertion/deletion (I/D) polymorphism is a potential risk factor for poor prognosis in IgA nephropathy, and that this deletion polymorphism predicts the therapeutic efficacy of ACE inhibition on proteinuria and, potentially, on progressive deterioration of renal function in patients with the nephropathy.     

造血系统恶性肿瘤患者血清sIL—2R检测的临床意义

使用ＥＬＩＳＡ双抗夹心法对临床４３例造血系统恶性肿瘤患者及２０例健康体检人员的血清ｓＩＬ－２Ｒ进行检测，并对ＡＬＬ和ＡＮＬＬ复发与未复发患者的血清ｓＩＬ－２Ｒ水平进行了比较分析。实验结果表明，血清ｓＩＬ－２Ｒ水平的升高是造血系统恶性肿瘤的重要标志之一；测定血清ｓＩＬ－２Ｒ水平对造血系统恶性肿瘤的辅助诊断、疗效观察及预后估计具有重要意义。     

肝病患者肝组织中丙型肝炎病毒感染的初步研究

采用直接酶标记法对174例慢性肝炎、重症肝炎和肝癌组织中的HCV抗原进行了检测,HCV 抗原的检出率分别为10.71％、8.10％和2.68％。表明在我国慢性和重症肝病中存在HCV的感染。通过对HCV与HBV 感染关系的研究,发现肝内HBV 标志阳性和阴性者HCV抗原的检出率无明显差异,说明HCV感染与HBV感染之间似无明显关系。