3种镍化合物转化细胞中DNA损伤的研究

[目的]探讨3种不同的镍化合物转化细胞中是否存在DNA链断裂和DNA-蛋白质交联等DNA损伤,进一步揭示不同溶解度镍化合物的相对致癌性。[方法]以培养液为溶剂对照,B(a)P为阳性对照,3种镍化合物转化BALB/c-3T3细胞中的DNA链断裂研究采用单细胞凝胶电泳试验(彗星试验),DNA-蛋白质交联物的检测则应用125I-后标记技术。[结果]不溶性结晶型硫化镍(NiS)和2种水溶性镍化合物(NiCl2和NiSO4)在中等细胞毒性反应剂量水平上所诱导的BALB/c-3T3转化细胞中,与非转化对照细胞(DNA慧星尾长13.4±1.75 μm)比较,有明显的DNA链断裂和DNA-蛋白质交联形成,其中以NiS所致的遗传损害最为显著,表明DNA链断裂和DNA-蛋白质交联这两项遗传终点是有用的生物标志,并与镍的细胞转化及其相对致癌作用相关。[结论]除了不溶性NiS具有强致癌性外,部分水溶性镍化合物如NiCl2也具有较强的致癌作用,部分解释了不同种类镍化合物的细胞转化作用及其相对致癌性。     

硫化氢在大鼠肝星状细胞氧应激中的作用

目的利用铁超载的方法在体外复制肝纤维化的氧应激模型，给予H2S供体硫氢化钠（NaHS）和内源性H2S作用的KATP通道阻滞剂格列苯脲（GLBN），论证氧应激下硫化氢对HSC细胞具有保护作用的假说。方法将HSC—T6分为8组：空白组、对照组、NaHS组（分为3个浓度组）、格列苯脲组（分为3个浓度组）。用CCK-8试剂盒测定HSC细胞增殖情况；用MDA试剂盒测定上清液MDA（丙二醛）含量；用SOD（超氧化物歧化酶）试剂盒测定上清液和裂解液中SOD活力；用RT—PCR试剂盒检测p38基因表达水平。结果1．Fe—NTA能够促进HSC的增殖，使p38基因表达水平降低、SOD活性降低、MDA浓度提高。对照组和空白组有明显差异（P〈0．05）；2．给予NaHS处理后，细胞增殖减慢，上清液中MDA含量下降，上清液、裂解液中SOD活性提高，p38基因表达水平增高（P〈0．05）；3．给予GLBN处理后，各项指标结果与给予NaHS处理后结果相对应，各组与对照组比较均有明显差异（P〈0．05）。结论氧应激下硫化氢对HSC细胞具有保护作用，可抑制肝纤维化的发生发展。     

硫化氢中毒致8例患者周围神经损害的临床分析

目的：探讨硫化氢中毒患者周围神经损害的临床特征和肌电图表现。方法：回顾性分析温岭医院收治的8例渔舱硫化氢中毒患者周围神经损害的临床资料。结果：硫化氢中毒致患者双侧正中神经、尺神经、腓总神经运动端潜伏期和神经传导速度明显慢于健康对照组，但诱发电位波幅无明显变化。结论：渔舱硫化氢中毒可致患者周围神经的亚急性损伤，提示在抢救急性硫化氢中毒的同时应早期发现和治疗周围神经的损害。     

Nickel allergy: tolerance to metallic surface-plated samples in nickel-sensitive humans and guinea pigs

The purpose of this work is to evaluate in nickel-sensitive patients and guinea pigs the tolerance to nickel samples, surface-plated with one or several metals of varying structures and thicknesses. All the metal samples elicited allergic reactions in the guinea pig. In humans, absolute tolerance was not observed for any sample. In humans, the interposing of a layer of bright copper between nickel and surface chrome greatly increased the tolerance.     

Scanning electron microscopy of the metal-tissue interface: II Observations with lead,copper, nickel,aluminium, and cobalt

The nature of the metal-tissue interface following the implantation of five pure metals, lead, copper, nickel, aluminium and cobalt, in rats has been observed by scanning electron microscopy. The general conculsion, derived from light microscopy that the tissue response to pure metals is characteristic of and specific to individual pure metals has been confirmed in this study. However, far more detailed observations of factors such as the extent of metallic corrosion, the distribution of red blood cells, platelets and other cells in the capsule and adherent to the metal surface, have been possible with SEM.     

The use of sodium sulfide to separate mercury from tissues preserved in cialit and merthiolate solutions

Summary The purpose of the present experiment was to look at the dissolution time in physiological sodium chloride (0.9% NaCl) and sodium sulfide (Na₂S) of any mercury (Hg) contained in human auditory ossicles and cartilage after preservation in Cialit and Merthiolate. Both homograft tissues produced almost identical graph complexes. Under static conditions 10 g Hg could be found in NaCl after 15 min, whereas there was complete demercurization after 3 min in Na₂S. The dissolution time in NaCl subjected to constant stirring was about 10 min and was less than 1min in Na₂S. For the rapid elimination of Hg from auditory ossicles stored in preservatives containing Hg, our studies show that the use of a flowing solvent is advisable. Further, the extraction of Hg is quicker in sodium sulfide than in an isotonic solution of sodium chloride.     

Temperature,pH, salinity,hardness, and particulates mediate nickel toxicity to eubacteria,an actinomycete,and yeasts in lake,simulated estuarine,and sea waters

The survival of some eubacteria, an actinomycete, and yeasts after acute and chronic exposures to nickel (Ni) in lake, simulated estuarine, and sea waters and the influence of environmental factors on Ni toxicity were determined. Nickel toxicity to microbes in marine systems was reduced by increasing the salinity, by decreasing the temperature, and by the incorporation of simulated sediment. The toxicity of Ni to microbes in fresh water was reduced by increasing the pH, by increasing the hardness, and by the incorporation of suspended particulates. Chronic toxicity studies indicated that fresh waters are more sensitive than marine waters to Ni pollution, as microbial survival was greater in marine than in fresh waters stressed with equivalent concentrations of Ni.