硫化氢及一氧化氦气体信号分子在高原高血压发病中的作用

目的 探讨气体信号分子硫化氢（H2S）及一氧化氮（NO）在高原高血压的病理生理意义。方法 平原体检正常者进入海拔5000m高原（1～3）月期间，在高原暴露时间、劳动强度及生活条件相同的施工群体中随机抽样127人。依血压变化将其分为高原高血压（Ⅰ～Ⅲ级）组78人（进一步分为收缩期高原高血压组与舒张期高原高血压组），高原正常血压组49人，采取肘静脉血，采用敏感硫电极法测定其H2S浓度，Griess法测定血清NO含量。结果 高原高血压组、收缩期高原高血压组、舒张期高原高血压组的血清H2S与NO平均含量均显著增加，分别比正常血压组高34．5％，36．9％，31.7％（均P〈0．001）与28．4％，33．1％，39．7％，（均P〈0．05），尤以H2S更为突出；随着血压分级程度的升高H2S与NO血清含量相应增高，也以H2S更显著（R^2=0．918）；H2S与NO、舒张压间均有密切正相关关系及良好的拟和优度、与氧饱和度呈显著的负相关与拟和优度（R^2=0．374，P=0．001）。结论 H2S与NO的代谢失常可能参与了高原高血压发病过程。     

成批硫化氢中毒抢救的组织与管理

目的 :探讨成批硫化氢中毒患者抢救时的组织与管理。方法 :由护理部及监护室护士长统筹安排 ,将 15位患者分成由 7个监护小组组成的 7个监护小单元实施程序化抢救 ,并统一调配抢救物资、器械。结果 :14例患者抢救成功治愈 ,1例患者心肺复苏成功后死于多脏器功能衰竭。结论 :有效、合理的护理组织与管理 ,能够争取抢救时间 ,提高成批硫化氢中毒患者的抢救成功率。     

Monoamine oxidase inhibition as a sequel of hydrogen sulfide intoxication: increases in brain catecholamine and 5-hydroxytryptamine levels

Administration of sodium hydrosulfide (NaHS), an alkali salt of hydrogen sulfide (H₂S) at doses of 10 and 30 mg/kg, corresponding to sublethal and lethal doses (0.66 and 2.0 X LD₅₀) resulted in significant increases in regional catecholamine levels of the rat brain only after the dose of 2.0 × LD₅₀ of NaHS. Whereas the cortex and the cerebellum showed little or no change in catecholamine content, the hippocampus, striatum and brainstem all showed increases in noradrenaline and adrenaline. Additional analysis also showed that brainstem dopamine and 5-hydroxytryptamine levels (5-HT) increased as well. In vitro testing of sulfide for inhibition of monoamine oxidase (MAO) activity showed the anion to be inhibitory with an IC₅₀ of 39.1±3.6 M. Inhibition of MAO activity ex vivo could be demonstrated at a dose of 100 mg/kg but not at the lower dose of 30 mg/kg NaHS. Inhibition of enzyme activity could not be demonstrated at this lower dose, possibly due to the well known rapid intramitochondrial metabolism of sulfide. Correlation of synaptosomal and mitochondrial sulfide levels with enzyme inhibition data suggests that inhibition of MAO may be an important contributing factor to the mechanism(s) underlying loss of central respiratory drive after fatal intoxication with H₂S.     

Pigments of the Gastrointestinal Tract: A Comparison of Light Microscopic and Electron Microscopic Findings

It is now apparent that light microscopy and histochemistry failed to identify correctly the nature and composition of pigments in various gastrointestinal tract melanoses. In most instances it was thought that the pigment was melanin or a melanin-like substance. Electron microscopy (EM) and electron-probe energy dispersive x-ray analysis have rectified these errors and have shown the following: in melanosis coli the pigment granules contain lipofuscin; in melanoses ilei the pigment granules may contain either silicates and titanium or hemosiderin; and in melanosis duodeni the pigment granules contain iron sulfide. In melanosis esophagi it is not clear what the pigment is; it could be melanin or lipofuscin.     

心血管组织钙化时内源性硫化氢系统下调

目的：观察心血管组织钙化时内源性硫化氢生成系统(CSE/H2S)的变化，以探讨内源性硫化氢在心血管组织钙化中的作用及血管钙化的细胞分子机制。方法：在维生素D3 (Vit D3)和尼古丁(nicotine)诱导大鼠血管钙化模型上，测定钙含量、［45Ca2+］沉积及碱性磷酸酶（ALP）活性判断心血管钙化程度,采用生化法测定血浆、心肌组织和主动脉H2S含量及CSE活性，半定量RT-PCR方法测定心血管组织CSE mRNA水平。结果：钙化组大鼠心肌组织钙含量较对照组高3.8倍,主动脉钙含量、［45Ca2+］ 沉积及ALP 活性分别较对照组高6.8倍、1.4倍和 1.9倍（P＜0.01）；钙化组大鼠血浆H2S含量较对照组低39%（P<0.01），心肌和主动脉组织的 H2S含量也分别较对照组低39%和31%，CSE mRNA表达也分别低28％和36％（P<0.01），CSE活性分别低56%和53%(P<0.01)。结论：钙化心血管组织CSE/H2S通路受抑制，内源性H2S生成减少。     

硫化氢对体外大鼠肝星状细胞内Ca2+浓度变化及细胞增殖的影响

目的 研究硫化氢(H₂ S)对大鼠肝星状细胞-T6(HSC-T6) Ca²⁺浓度、细胞增殖的影响及其机制。 方法 活化HSC-T6用含10%小牛血清DMEM培养液制备为1×10⁵个肝星状细胞(HSC)悬液。钙离子荧光探针Fluo-3/AM负载细胞后，在不同刺激条件下，利用激光扫描共焦显微镜动态扫描HSC-T6细胞内Ca²⁺荧光强度（FI）变化，FI表示细胞内Ca²⁺浓度。四唑盐比色法，观察不同浓度H₂S供体——NaSH对HSC-T6细胞增殖的影响。 结果 低浓度H₂S（100μmol/L）明显降低HSC-T6细胞内Ca²⁺浓度（P<0.05)，而细胞增殖增加（增殖率为116%）；K_ATP通道阻断剂——格列本脲可阻断H2S的作用。高浓度H₂S（1mmol/L）刺激HSC-T6细胞内Ca₂₊浓度增加，但细胞增殖无明显变化(P＞0.05)。 结论 低浓度H₂S通过激活HSC-T6细胞K_ATP通道降低细胞内Ca²⁺浓度，可能通过调节细胞氧化应激促进细胞增殖；高浓度H2S刺激HSC-T6细胞内Ca₂₊浓度增加。提示H₂S在肝硬化门脉高压症的发生机制中具有双重作用。     

应用基因表达谱芯片研究硫化砷作用后K562细胞基因表达的变化

目的：利用基因表达谱芯片检测K562细胞在硫化砷作用前后基因表达的差异性进行比较研究。方法：研究对象为人慢性粒细胞白血病细胞株K562,用cy3和cy5两种不同的荧光染料通过逆转录反应将K562经硫化砷作用前后的mRNA分别标记成两种探针,并与载有一组靶的基因表达谱芯片进行杂交,通过计算机扫描分析得到这些基因在经硫化处理前后的表达差异,结果：筛选出包括与DNA结合,转录和转录因子,蛋白翻译,细胞周期等相关表达差异的基因共11条,其中7条表达上调,4条表达下调,结论：周期素E2,周期素G2可能参与硫化砷诱导K562细胞凋亡发生机制。     

Cumulative biochemical effects of repeated subclinical hydrogen sulfide intoxication in mouse brain

Summary Adult female NMRI mice exposed four times to 100 ppm hydrogen sulfide vapour for 2 h at 4-day intervals showed increasing inhibition of the cerebral cytochrome oxidase activity. Cerebral RNA decreased significantly after the fourth exposure. This change was accompanied by the reduced orotic acid uptake in the RNA fraction. At the same time, 2,3-cyclic nucleotide 3-phosphohydrolase activity used as a marker for glia increased. Acetylcholine esterase activity remained unchanged. The initial exposures also caused an increase in the superoxide dismutase activity and an increase in the glutathione concentration. The latter effects were abolished in the third and fourth exposures. The present data seem to indicate that the biochemical effects of repeated subclinical hydrogen sulfide intoxications are cumulative.     

N,N-二甲胺基硫代乙酰胺的合成研究

目的：研究尼扎替丁中间体N，N－二甲胺基硫代乙酰胺的合成，考察不同反应温度，反应时间对收率的影响。方法：采用硫氢化钠为催化剂，硫化氢气体直接通入原料N，N－二甲胺基乙腈中反应，然后通过过滤，减压蒸馏得粗品，用异丙醇重结晶得成品，结果：控制反应温度约50℃，通入硫化氢气体反应6小时。结论：该合成方法为N，N－二甲胺基硫代乙酰胺的工业化生产提供了一条新途径。