模糊数学方法用于职业危害因素的综合评价

模糊数学方法用于职业危害因素的综合评价徐新云（湖南省劳动卫生职业病研究所，长沙４１０００７）用模糊数学方法进行综合评价时，首先要确定评判等级，各评判因素在不同等级中的取值，以及各评判因素的权重系数三方面内容。本文将评判等级定为优、良、一般、差、很差５...     

Multiplex PCR analysis of in vivo-arising deletion mutations in the hprt gene of human T-lymphocytes

A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10^?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc.     

荧光分光光度法测定水产品中烷烃类、芳烃类污染物

目的：对使用荧光分光光度法测定水产品中烷烃类、芳烃类污染物的方法进行验证,并检测三类样品。方法：通过氢氧化钠-乙醇皂化处理,用正已烷萃取,用石油醚溶解,测量萃取物荧光强度值进行定量。结果：测得标准油在0.00～12.0μg/ml范围内线性关系良好,相关系数0.9999,检出限为0.2 mg/kg,平均回收率90.2%,RSD5.4%。结论：本法准确度、灵敏度高,检出限低,操作稳定性好。     

3,6-(二甲氨基)-二苯骈碘杂六环葡萄糖酸盐对AGEP引起的大鼠主动脉平滑肌细胞增殖及牛主动脉内皮细胞内皮素和一氧化氮改变的影响

目的 :观察 3 ,6 (二甲氨基 ) 二苯骈碘杂六环葡萄糖酸盐对AGEP引起的大鼠主动脉平滑肌细胞增殖及牛主动脉内皮细胞内皮素和一氧化氮改变的影响。方法 :采用牛血清白蛋白 (BSA)与不同浓度葡萄糖 (0 ,2 0 ,5 0 ,80mmol·L-1)体外孵育制备糖基化终产物 (AGEP) ,应用 [3 H] TdR掺入法和MTT比色法观察I-93对重度糖化的AGEP诱导的大鼠主动脉平滑肌细胞 (ASMC)增殖的影响 ;应用放射免疫技术及Greiss法观察I -93对AGEP引起的牛主动脉内皮细胞 (BAEC)释放内皮素 1(ET 1)和一氧化氮 (NO)的影响。结果 :I-93 10 -7～ 10 -5mol·L-1能明显抑制AGEP引起的ASMC增殖 ,其 [3 H] TdR掺入量和MTT比色法的最大抑制率分别为79 .4%和 44 .2 %。随AGEP糖浓度的增加 (2 0～ 80mmol·L-1) ,BAEC培养液中ET 1含量亦逐渐上升 [(4 93± 63 )～ (779± 10 5 )ng·L-1] ,I -93 10 -7～ 10 -5mol·L-1能明显抑制重度糖化的AGEP促进ET 1释放的作用 ;I -93对AGEP灭活NO的作用有剂量依赖性抑制效应。结论 :I -93有抑制ASMC增殖的作用 ;对AGEP诱导的BAEC释放ET 1和NO间平衡失调有调节作用 ,在防治阻塞性血管疾病方面I -93具有潜在的应用价值     

多种肿瘤标志物联合检测肺癌的临床意义

目的 评价血清肿瘤标志物甲胎蛋白(AFP)、癌胚抗原(CEA)、糖类抗原50(CA50)、糖类抗原19—9(CA19—9)、铁蛋白(SF)、神经元特异性烯醇化酶(NSE)、细胞角蛋白19片段(CYFlRA21—1)水平对肺癌诊断的临床价值。方法 测定72例肺癌患者和40例良性肺病患者的血清AFP、CEA、CA50、CA19—9、SF、NSE、CYFRA21—1水平，比较两组的差异。结果 肺癌组患者CEA、CA50、CA19—9、SF、NSE、CY—FRA21—1水平高于良性肺病组，AFP对肺癌的诊断价值不大。NSE CYF、RA21—1的联合检测具有良好的阳性和阴性预测值。六项联合检测的敏感性和准确性最高，但与两项联合检测的敏感性和准确性差异无统计学意义。结论 NSE CYFRA21—1的联合检测具有良好的临床应用前景。     

股骨多段闭合骨折病人术前凝血功能的变化

目的 探讨股骨多段闭合骨折病人术前凝血功能的变化。方法 选择创伤股骨多段闭合骨折后当天入院的病人20例,年龄19-45岁,ASA Ⅰ级,为试验组(Ⅰ组);选择健康成年人15人,年龄21-39岁,作为对照组(Ⅱ组);Ⅱ组于清晨空腹采上肢静脉血标本,Ⅰ组病人入院后于骨折的第2天、第6天(手术当天清晨)空腹采上肢静脉血样本,检测血栓弹力图(TEG)指标[R时间、K时间、α角、血栓最大幅度(MA)、血栓硬度(G)]、D-二聚体浓度(D-Di)、血小板计数(PLC)及血小板聚集率(PAgR)的变化。结果 Ⅱ组TEG指标、D-Di、PLC及PAgR均在正常范围。与Ⅱ组比较,Ⅰ组骨折后第2天,K时间缩短(P<0.05),α角、MA、G及D-Di增高(P<0.01);骨折后第6天,R时间缩短(P<0.05),α角、MA、G、D-Di、PLC及PagR增高(P<0.01)。与骨折后第2天比较,Ⅰ组骨折后第6天MA、G、PLT及PAgR增高(P<0.05或0.01)。结论 病人创伤骨折后凝血功能24 h内增强,随时间的延长至术日呈高凝状态,应加强术中管理,并采取相应措施预防术中静脉血栓的发生。     

Biocompatibility pattern of a bicarbonate/lactate-buffered peritoneal dialysis fluid in APD: a prospective, randomized study.

BACKGROUND: In chronic ambulatory peritoneal dialysis, bicarbonate-buffered fluids, with their neutral pH and less advanced glycosylation end-products (AGE) and glucose degradation products (GDP), have better biocompatibility than conventional peritoneal dialysis (PD) solutions. That difference may be more beneficial in automated peritoneal dialysis (APD), due to its more frequent exchanges and longer contact times with fresh dialysate. We performed a prospective, randomized study in APD patients to compare the biocompatibility of conventional and bicarbonate/lactate-buffered PD fluids. METHODS: We randomized 14 APD patients to have APD with either conventional or bicarbonate/lactate-based fluids. After 6 months, both groups changed to the other solution. The overall observation period was 12 months. After 1 and 5 months and again after 7 and 11 months, phagocytotic and respiratory burst capacities of effluent peritoneal macrophages were determined. Plasma interleukin (IL)-6 and C-reactive protein (CRP) as well as effluent IL-6, CRP, transforming growth factor (TGF)-beta 1, AGE and CA125 concentrations were measured. Inflow pain was quantified using a patient questionnaire. RESULTS: Respiratory burst capacity remained unchanged and phagocytotic activity increased significantly during APD (P<0.001) with the bicarbonate/lactate fluid. Effluent IL-6 release was significantly lower than with the lactate fluid (P<0.05). While in the effluent TGF-beta 1 was unaffected, AGE concentration was lower after bicarbonate/lactate treatment (P<0.05). Effluent CA125 concentration, an indicator of mesothelial cell integrity, was higher (P<0.05) in neutral effluents. Finally, patients' inflow pain diminished (P = 0.05) when using the neutral fluid. CONCLUSIONS: The use of a neutral PD fluid in APD improved patients' inflow pain as well as biocompatibility parameters reflecting enhanced phagocytotic activity of peritoneal macrophages, reduced constitutive inflammatory stimulation (IL-6), reduced AGE accumulation in the peritoneal cavity and better preservation of the mesothelial cell integrity. From the biocompatibility point of view, a neutral fluid with low GDP content can be recommended as the primary choice for APD.     

次氯酸对人血清白蛋白的氧化修饰影响及与高级氧化蛋白产物的关系

目的 研究次氯酸对人血清白蛋白(HSA)的氧化修饰影响及与高级氧化蛋白产物(AOPPs)之间的关系。 方法 有氧条件下在恒定浓度的HSA(60 mg/ml)内加入不同浓度次氯酸(0、1、5、10、20、30、40、50、60 mmol/L，最终浓度)，观察氧化剂对HSA的修饰作用。凝胶排阻色谱法检验HSA氧化修饰结果，在线光谱扫描(190 nm~400 nm)分析修饰产物的光谱特性。结果 次氯酸可氧化修饰人血清白蛋白，其修饰产物主要为二聚体HSA和六聚体HSA。发现次氯酸对HSA单体和HSA二聚体的氧化修饰为一级反应；对诱导生成的AOPPs为准一级反应；而对诱导生成的HSA六聚体则为二级修饰反应。同时发现白蛋白对AOPPs的主要贡献者是六聚体形式的HSA，光谱分析表明HSA聚集体的最大吸收峰发生红移，提示HSA聚集体是由于蛋白中的酪氨酸残基通过氧化交联方式而聚集形成的。 结论 HSA经次氯酸处理后主要发生了蛋白聚集。而对AOPPs的主要贡献者是六聚体形式的HSA。     

糖基化终末产物对大鼠肾系膜细胞纤溶酶原激活物抑制物-1表达韵影响

目的：观察糖基化终末产物（AGEs）对大鼠肾系膜细胞纤溶酶原激活物抑制物-1（PAI-1）表达的影响及其与细胞外基质（ECM）成分含量的关系。方法：体外培养正常大鼠肾系膜细胞，分别用糖化牛血清白蛋白（AGEs）及未经糖化的牛血清白蛋白（BSA）处理，以常规培养的肾系膜细胞作为对照，检测不同时间、不同浓度AGEs对纤维连接蛋白（FN）、Ⅳ型胶原、PAI-1表达的影响。MTT法检测AGEs对系膜细胞增殖的作用，ELISA测定条件培养基中FN、Ⅳ型胶原及PAI-1蛋白含量，逆转录聚合酶链式反应（RT—PCR）检测系膜细胞PAI-1 mRNA的表达。结果：与相应浓度的BSA比较，AGEs（0—200mg／L）对系膜细胞增殖无明显影响，但可不同程度地刺激系膜细胞FN、Ⅳ型胶原、PAI-1蛋白的产生。RT—PCR检测显示，给予AGEs（100mg／L）的系膜细胞PAI-1 mRNA的表达明显增加（P〈0．01）。结论：AGEs促进系膜细胞PAI—1的表达，提示AGEs通过上调PAI-1的表达而减少细胞外基质降解，可能是糖尿病肾病细胞外基质积聚的原因之一。     

DNA damage by the glycation products of glyceraldehyde 3-phosphate and lysine

Summary In order to evaluate whether base modifications, apurinic/apyrimidinic site formation, strand breaks, or a combination of these lesions results from the interaction of glycation products with DNA, plasmid DNA was first reacted with these products, and then subjected to digestion with endonuclease III and endonuclease IV of Escherichia coli. Analysis of the differential effects of digestions with these enzymes by electrophoresis on agarose gels demonstrated that reactive glycation products produce both base modification and apurinic/apyrimidinic sites in DNA, in addition to the strand breaks observed after incubation with glycation products alone. These types of DNA damage may occur in specific diabetic cells where elevated levels of glycating sugars are associated with pathologic dysfunction. [Diabetologia (1994) 37: 145–149] Received: 28 May 1993 and in revised form: 30 August 1993