Effects of arsenic on DNA synthesis in human lymphocytes

Effects of arsenic on DNA synthesis in human lymphocytes were biphasic: Either trivalent (arsenic trioxide and sodium arsenite) or pentavalent (sodium arsenate) arsenic compounds at very low concentrations enhanced DNA synthesis in human lymphocytes stimulated by phytohemagglutinin (PHA), whereas higher concentrations inhibited DNA synthesis. There were differences among individual susceptibities to arsenic-induced DNA synthesis. Either stimulating or inhibiting effects of trivalent arsenic on DNA synthesis in PHA-stimulated lymphocytes were always stronger than those of pentavalent arsenic. Both trivalent and pentavalent arsenic could be rapidly taken up into the human lymphocytes and immediately stimulate or inhibit DNA synthesis. A possible dual effect of arsenic at very low concentrations as both comutagen and inhibitor of mutagenesis is discussed.     

奥沙利铂联合氟尿嘧啶、亚叶酸钙术前化疗对大肠癌细胞早期凋亡的影响

目的　观察奥沙利铂联合氟尿嘧啶、亚叶酸钙诱导大肠癌细胞早期凋亡的效果。方法　大肠癌患者 2 1例 ,术前 1周应用奥沙利铂联合氟尿嘧啶、亚叶酸钙化疗 ,术中取大肠癌组织 ,应用流式细胞术 (AV与PI双参数法 )检测其凋亡 ;并与 2 0例术前未化疗的大肠癌患者进行比较。结果　术前化疗组 (治疗组 )大肠癌细胞凋亡比例明显高于术前未化疗组 (对照组 ) (P <0 .0 1 )。结论　奥沙利铂联合氟尿嘧啶、亚叶酸钙化疗可通过促进大肠癌细胞凋亡而发挥其抗癌作用     

Glucuronidation of Catechol Estrogens by Expressed Human UDP-Glucuronosyltransferases (UGTs) 1A1, 1A3, and 2B7

Catechol estrogens are major estrogen metabolites in mammalsand are the most potent naturally occurring inhibitors of catechol-aminemetabolism. These estrogen compounds have been implicated incarcinogenic activity and the 4/2-hydroxyestradiol concentrationhas been shown to be elevated in neoplastic human mammary tissuecompared to normal human breast tissue. Three human liver UDP-glucuronosyltransferases,UGT2B7, UGT1A1, and UGT1A3, have been shown to catalyze theglucuronidation of catechol estrogens and lead to their enhancedelimination via urine or bile. The present study was designedto study the kinetic interaction of expressed human UGT2B7(Y)or (H), UGT1A1, and UGT1A3 toward 2- and 4-hydroxycatechol estrogens.cDNAs encoding UGT2B7(Y) or (H), UGT1A1, and UGT1A3 were expressedin HK293 cells, and cell homogenates or membrane preparationswere used to determine their glucuronidation ability. UGT2B7(Y)reacted with higher efficiency toward 4-hydroxyestrogenic catechols,whereas UGT1A1 and UGT1A3 showed higher activities toward 2-hydroxyestrogens.UGT2B7(H) catalyzed estrogen catechol glucuronidation with efficienciessimilar to UGT2B7(Y). Flunitrazepam (FNZ), a competitive inhibitorof morphine glucuronidation in hepatic micro-somes, competitivelyinhibited catechol estrogen glucuronidation catalyzed by UGT2B7(Y),UGT1A1, and UGT1A3. Buprenor-phine, an opioid substrate thatreacts at high efficiency with each of these UGTs, was alsostudied. FNZ competitively inhibited buprenorphine glucuronidationwith UGT1A1 and UGT2B7 but had no inhibitory activity towardUGT1A3. This suggests that buprenorphine and 2-hydroxycatecholestrogens react with separate active sites of UGT1A3. A catecholamine,norepinephrine, did not inhibit UGT2B7(Y) UGT1A1, and UGT1A3-catalyzedglucuronidation of catechol estrogens. These results also suggestthat drug-endobiotic interactions are possible in humans andmay have implication in carcinogenesis.     

癫痫灶切除术28例报告

对２８例顽固性癫痫病例的病灶定位、手术方式、术后疗效几方面进行分析总结。方法对２８例病史在３ａ以上癫痫患者，术前进行３次以上脑电生理和ＣＴ（ＭＲＩ）检查，依照检查结果选择手术方式，术中在皮层脑电监测下将癫痫（病）灶切除。结果依Ｗｉｌｉａｓｏｎ疗效评定标准总有效率９２．８％（２６／２８）。结论治疗效果主要取决于术前、术中致痫灶的精确定位。正确的选择手术方式则是预防并发症的关键。只有借助脑电生理、ＣＴ（ＭＲＩ）等手段反复检查，才能最大限度地提高定位精确度，取得良好的治疗效果。     

风心瓣膜病变患者红细胞膜钠、钙泵活性和脂质过氧化的变化

用酶解法和Ｈ２Ｏ２分解法分别测定２８例风心瓣膜病变患者红细胞膜钠泵（Ｎａ＋、Ｋ＋－ＡＴＰ酶）、钙泵（Ｃａ２＋、Ｍｇ２＋－ＡＴＰ酶）活性和膜过氧化氢酶（ＣＡＴ）活性，并用硫代巴比妥酸比色法测定患者红细胞膜脂质过氧化物（ＬＰＯ）含量。患者红细胞膜Ｎａ＋、Ｋ＋－ＡＴＰ酶活性和Ｃａ２＋、Ｍｇ２＋－ＡＴＰ酶活性分别显著低于正常人３４．７５％（Ｐ＜０．０１）和２６．７７％（Ｐ＜０．０１）；ＣＡＴ活性显著低于正常人２０．０７％（Ｐ＜０．０１）；而患者ＬＰＯ含量却显著高于正常人９７．５０％（Ｐ＜０．０１）。结果提示风心病患者瓣膜病变与质膜钠、钙泵活性变化以及膜脂质过氧化作用有关。     

益气活血法治疗冠心病心绞痛量效关系的临床研究

:60例冠心病心绞痛患者随机分为 3组 ,分别给予大、中、小 3种剂量的益气药党参和相同剂量的活血药丹参。结果表明益气活血法能明显缓解心绞痛 ,同时减轻乏力、心悸等症状 ,改善左室功能 ,并提示随着党参量的增加 ,呈现一定的量效关系。     

腰骶段椎间盘膨出与突出的CT诊断

利用高分辨率CT成象检查225例有腰背痛及坐骨神经痛病例,检出52例椎间盘膨出(23.1%),89例椎间盘突出(35.6%)。极大部分伴有退行性骨质改变,极小部分有黄韧带增厚,所有这些均能对椎管内神经造成压迫。本组椎间盘膨出发病率也较高,作者认为对这种病征应该引起重视并要作进一步探究。对椎间盘膨出及突出与其伴随的退行性骨/软组织改变作了分析与讨论。     

“钾异心”停搏液对缺血心肌电活动的影响

观察“钾异心”停搏液对缺血心肌的保护作用并与高钾停搏液比较。用无糖不充氧台氏液浸浴离体豚鼠右心室乳头肌３ｈ造成缺血损伤，以心肌细胞电生理参数为指标。缺血后心肌电生理参数下降，其中以“钾异心”组下降最快速彻底，复灌后只有“钾异心”组电生理各参数都恢复正常。结论“钾异心”停搏液可快速彻底抑制心肌电活动有效保护缺血心肌。     

卷烟厂女工尿尼古丁测定及其吸收干预措施

为了全面评价卷烟厂工人在生产过程中接触烟草的水平，我们对５６名制丝车间非吸烟女工、６５名包装车间非吸烟女工及５４名果糖饮料厂非吸烟女工进行尿中尼古丁含量的测定，并对制丝车间摆把工种女工尼古丁吸收的干预措施效果进行研究。结果表明，制丝车间及包装车间女工工作结束时尿中尼古丁含量分别为４４．８±５，１ｎｇ／ｍｌ和９９±５４ｎｇ／ｍｌ，均显著高于对照组。制丝组女工工作结束时尿中尼占丁含量亦明显高于班前含量（１１．４±６．７ｎｇ／ｍｌ）。尼古丁吸收干预试验结果表明，工人上班时同时使用口罩、手套和在夏季开启通风设备对尼占丁的吸收均有良好的防护作用。     

大鼠输精管注射HFMC后输精管内pH值的观察

本实验选用生育力正常成年雄性ＳＤ大鼠２５只，随机分为５组，行一侧输精管ＨＦＭＣ注射术，剂量为１０％ＨＦＭＣ２０μｌ，沉淀剂２０μｌ；另一侧输精管注射生理盐水４０μｌ对照，于注射时和注射后１、３、６、９和１２月分别测定双侧输精管ｐＨ值，其结果为注射ＨＦＭＣ侧输精管ｐＨ明显降低，为５．１８－５．８２，生理盐水对照侧为７．０４－７．６４，并随推移，注射ＨＦＭＣ侧输精管ｐＨ值逐渐升高，于术后１２月基本恢复