铅抑制NF-κB、Bcl-2蛋白表达诱导人肾小管上皮细胞凋亡

目的研究醋酸铅对人肾小管上皮细胞系HK-2细胞NFκB、Bcl-2表达的影响及与细胞凋亡的关系。方法体外培养HK-2细胞分为0、2.5、5、10、20μmol/L醋酸铅组,分别染毒72h,应用间接免疫荧光-流式细胞术检测HK-2细胞NF-κB、Bcl-2蛋白表达的改变,用Annexin-V/PI双染法检测细胞凋亡。结果随着染铅剂量增加HK-2细胞NF-κB、Bcl-2蛋白表达逐步降低,NF-κB与Bcl-2降低显著相关(r=0.71,P<0.01);细胞凋亡率随着铅剂量增加而增加,在5、10、20μmol/L铅组与对照组比较差别有统计学意义(P<0.01);细胞凋亡率与NF-κB、Bcl-2蛋白表达呈明显负相关(r=-0.625,P<0.01;r=-0.709,P<0.01)。结论醋酸铅能下调HK-2细胞NF-κB、Bcl-2基因的表达,这可能是其诱导HK-2细胞凋亡的途径之一。     

核因子-kB、p53及Bcl-2在铅诱导PC12细胞凋亡中的作用

目的 探讨核因子kB(NF-KB),p53及Bcl-2在铅诱导PC12细胞凋亡中的作用.方法 应用细胞培养、流式细胞术、RT-PCR、Western Blot的方法分析NF-kB、p53、Bel-2基因的表达情况,研究醋酸铅诱导PC12细胞凋亡及其分子机理.结果 PC12细胞经不同浓度醋酸铅(100、200和400μmol/L)处理24h后,用流式细胞仪检测其凋亡率(n=3),铅组凋亡率明显高于对照组,改变呈剂量依赖性.差异有显著性(P<0.05).RT-PCR结果显示NF-kB p65 mRNA、p53 mRNA转录水平随铅剂量升高而升高(P<0.05),两基因表达的改变呈剂量依赖性.Western Blot结果显示,表明随着铅浓度的增加,Bcl-2蛋白表达逐渐降低.结论 铅诱导PC12细胞凋亡的这种效应可能与增强NF-kB及D53基因的活性、降低Bcl-2基因的活性有关.     

醋酸铅对人肾小管上皮细胞凋亡及超微结构的影响

目的 探讨醋酸铅对人肾小管上皮细胞(HK-2)凋亡的作用及对超微结构的影响。方法 经5、10、20 μmol/L醋酸铅染毒HK-2细胞24h后,Hochest33342染色法观察细胞形态学变化,透射电子显微镜下观察细胞超微结构的变化,分光光度计检测细胞培养上清中乳酸脱氧酶(LDH)活力、丙二醛(MDA)含量,DNA Ladder实验检测醋酸铅对HK-2基因组的影响,应用流式细胞仪检测细胞凋亡率。结果 Hochest33342-PI染色显示,染铅组细胞呈凋亡形态学改变。透射电子显微镜下观察发现,染铅组细胞胞质内出现空泡,核同缩,核膜结构模糊,并出现凋亡小体。染铅组细胞培养上清中LDH活力及MDA含量较对照组明显升高,差异有统计学意义(P＜0.01)。HK-2基因结果显示,染铅组出现较为明显的DNA损伤现象。5、10、20 μmol/L染铅组细胞凋亡率分别为14.16％±2.94％、19.45％±2.73％、25.01％±3.97％,均明显高于对照组(5.81％±2.18％),差异均有统计学意义(P＜0.05)。结论 醋酸铅可促进HK-2细胞凋亡,进而影响肾脏正常功能。     

雌性SD大鼠围产期铅染毒对仔鼠脑细胞Brn-3a表达及凋亡的影响

目的探讨铅对中枢神经系统神经细胞内转录因子Brn-3a表达的影响及诱导细胞凋亡的作用.方法20只受孕SD大鼠随机分为4组,经围产期饮水染铅(0、0.5、1.0、2.0g/L)后,对其21日龄仔鼠不同脑区的Brn-3a蛋白表达水平进行观察,采用流式细胞仪测定细胞凋亡率及应用间接免疫荧光反应测定Bcl-2蛋白的表达情况.结果染铅组大鼠大脑皮层、海马及小脑的Brn-3a蛋白表达的阳性面积比、平均灰度与对照组比较,其差异均有统计学意义(P＜0.05或P＜0.01),并呈剂量依赖性的变化,Brn-3a表达低于对照组;染铅组大鼠海马组织细胞凋亡率高于对照组(P＜0.01);染铅组大脑皮层、海马、小脑部位Bcl-2蛋白表达下降(P＜0.05或P＜0.01).结论铅对发育期神经组织的损害可能与其诱导的神经细胞凋亡相关联,铅致Brn-3a蛋白表达下降可能是铅致神经细胞凋亡的途径之一.     

Bcl-2和Bax蛋白及基因在铝致神经细胞毒性作用中的表达

目的 通过研究Bcl-2和Bax蛋白及基因在铝致神经细胞毒性作用中的表达,以探讨铝对体外培养大鼠神经元细胞的神经毒性作用.方法 用不同浓度氯化铝体外培养大鼠神经元细胞染毒,用原位缺口末端标记（TUNEL）法和扫描电镜观察检测细胞凋亡,免疫组化法测定Bcl-2和Bax蛋白含量,RT-PCR法测定Bcl-2和Bax基因表达量.结果 （1）TUNEL法检测DNA碎片随染铝剂量的加大而增加,扫描电镜观察到了凋亡细胞典型的出芽现象和细胞裂解及凋亡小体的释放.（2）免疫组化和RT-PCR法检测Bcl-2蛋白含量及基因表达量随染铝剂量的加大而减少（P＜0.01,r=-0.695;P＜0.05,r=-0.647）,反之,Bax蛋白含量及基因表达量随染铝剂量的加大而增加（P＜0.01,r=0.676;P＜0.01,r=0.794）.Bcl-2/Bax与铝的作用剂量有关（P＜0.01,r=-0.655;P＜0.01,r=-0.777）.结论 低剂量铝暴露能够诱导神经元凋亡,Bcl-2和Bax蛋白及基因表达在铝致神经细胞凋亡的过程中发挥了重要的调控作用.     

氯化甲基汞对NB4细胞凋亡率及Bcl-2和Bax表达水平的影响

目的 研究氯化甲基汞(MMC)对NB4细胞凋亡率及凋亡相关蛋白表达水平的影响.方法 NB4细胞经1.25、2.5、5、10和20 μmol/L MMC作用24 h,采用FITC- Annexin Ⅴ/PI双染法进行细胞凋亡率的检测;同时用Western Blot检测凋亡相关蛋白Bcl-2、Bax的表达.结果 NB4细胞接触不同剂量MMC 24 h,随着剂量增加凋亡率不断增加,2.50 μmol/L的细胞凋亡率[(20.87±3.70)%]与空白对照组[(11.86±3.77)%]比较差异有统计学意义(P＜0.05);且随着浓度增加Bcl-2表达水平逐渐下降,Bax表达水平不断增加.结论 MMC能促进NB4细胞凋亡,且呈剂量依赖性.     

铅对HK-2细胞转分化及纤维化相关因子表达的影响

目的 探讨铅在人肾小管上皮细胞表型转化中的作用及对纤维化相关因子的影响.方法 体外培养人类近端肾小管上皮细胞系(HK-2)细胞,以2.5、5.0、10.0μmol/L醋酸铅剂量染毒,以Oμmol/L醋酸铅剂量组为对照组,应用形态学、间接免疫荧光-流式细胞术、反转录-聚合酶链反应(RT-PCR)观察醋酸铅染毒72 h HK-2细胞形态、α-平滑肌肌动蛋白(α-SMA)和纤维连接蛋白(FN)表达的改变,以及对纤维化相关因子转化生长因子(TGF-β1)、结缔组织生长因子(CTGF)的影响.结果 5.0、10.0μmol/L醋酸铅可使肾小管上皮细胞形态发生明显改变.5.0、10.0μmol/L醋酸铅组α-SMA阳性细胞率分别为9.32%,和6.98%,明显高于对照组,差异有统计学意义(P<0.01);与对照组比较,5.0、10.0μmol/L醋酸铅组FN蛋白表达增高,差异有统计学意义(P<0.01).与对照组比较,5.0、10.0μmol/L醋酸铅组细胞TGF-β1MRNA以及蛋白质表达明显增强,2.5、5.0、10.0μmol/L醋酸铅组CTGFmRNA以及蛋白质表达明显增强,差异均有统计学意义(P<0.05或P<0.05).结论 铅在体外可诱导肾小管上皮细胞转分化并能增强FGF-β1、CTGF、FN表达.     

铅致原代培养海马神经元凋亡及Bcl-2、Bax、p53和NOS1基因表达的影响

目的观察铅对原代培养海马神经元的致凋亡作用并初步探讨其机制。方法原代培养乳大鼠海马神经元,不同浓度的醋酸铅(50、100和200μg/ml)染毒后,Giemsa染色观察铅诱导海马细胞凋亡的形态学改变,流式细胞仪检测铅诱导海马神经元的凋亡率,免疫细胞化学染色观察各浓度组细胞Bcl-2、Bax和p53表达,激光扫描共聚焦显微镜定量分析各浓度组神经元胞浆中游离Ca2+的平均荧光强度。结果Giesma染色观察发现一定浓度醋酸铅作用于海马神经元后出现凋亡的形态学改变,且与剂量相关;流式细胞术检测结果铅浓度分别为50、100、200μg/ml作用细胞24h后,可致海马神经元凋亡率增加,与对照组相比均有统计学意义(P<0.01);免疫细胞化学染色结果表明Bcl-2蛋白表达随染铅剂量增大而减少,染色强度逐渐降低,Bax、p53表达随染铅剂量增大而上调,与对照组相比,细胞积分光密度(IOD)值有统计学意义(P<0.01);激光共聚焦显微镜检测结果显示随着醋酸铅剂量的增大,细胞内液Ca2+浓度也随着增大,醋酸铅3个浓度组的平均荧光强度均显著高于正常对照(P<0.01),并有剂量反应关系。结论铅可诱导海马神经元不同程度的凋亡,提示细胞内Ca2+浓度升高可能与铅致海马神经元损伤和诱导其凋亡有重要关系。推测铅在一定浓度范围内可能影响海马神经元在学习记忆等功能的正常发挥。     

有机碘和无机碘对人甲状腺细胞凋亡的影响

目的 研究有机碘和无机碘对体外培养的人甲状腺细胞形态和凋亡相关蛋白Bcl-2和Bax表达的影响.方法 取正常人甲状腺细胞进行培养,分别设对照(培养液)组和KI组(碘浓度分别为10-7、10-5、10-3 mol/L)及3,5-二碘酪氨酸(DIT)组(碘浓度分别为10-7、10-5、10-3 mol/L),分别加入相应浓度用培养液稀释的DIT和KI溶液,继续培养48 h.采用免疫组织化学技术测定细胞凋亡相关蛋白表达的情况.结果 与对照组相比,10-5、10-3 mol/L KI组和10-3 mol/L DIT组甲状腺细胞Bcl-2表达量较低,10-5、10-3 mol/L KI及DIT暴露甲状腺细胞Bax表达量较高,差异均有统计学意义(P＜0.05,P＜0.01);且随着KI或DIT暴露浓度的升高,甲状腺细胞Bcl-2表达量呈下降趋势,Bax表达量呈上升趋势.与相同剂量KI组相比,10-5、10-3 mol/L DIT组甲状腺细胞Bcl-2表达量较高,Bax表达量较低,差异均有统计学意义(P＜0.05,P＜0.01).结论 高碘可引起甲状腺细胞形态的改变并增强其细胞凋亡的发生,且DIT对甲状腺细胞的影响弱于KI.     

醋酸铅对人肾小管上皮细胞凋亡及Caspase-3的表达影响

目的探讨醋酸铅对人肾小管上皮细胞(HK-2)凋亡作用及Caspase-3活性的影响。方法醋酸铅(5、10、20μmol/L)染毒HK-26、12、24、48h后,四甲基偶氮唑蓝(MTT)检测细胞增殖。经铅(5、10、20μmol/L)染毒24h后细胞免疫化学法、RT-PCR和Western Blotting检测Caspase-3的转录与表达。结果与空白对照组相比,不同浓度的铅均不同程度的抑制了HK-2的增殖(P﹤0.01)。细胞免疫化学法、RT-PCR和Western Blotting结果显示醋酸铅组的Caspase-3转录与表达升高。结论醋酸铅可促进人肾小管上皮细胞的凋亡,Caspase-3参与了凋亡过程。     

Antifertility effects of PGE2 and PGF2alpha

The effectiveness of prostaglandins to modify egg transport, to stimulate uterine contractility and to induce luteolysis suggested their possible role as postcoital contraceptives. PGE₂ and PGF_2α were injected at 24 $\text{hours postcoitum (h p.c.)}$ or at 4 $\text{days postcoitum (d p.c.)}$ in rabbits. Effects on fertility were studied at autopsy 14 $\text{d p.c.}$ When PGE₂ was injected 24 $\text{h p.c.}$, 25% of the eggs failed to implant and 11% of the embryos were degenerating. The injection of PGF_2α at 24 $\text{h p.c.}$ inhibited the implantation of 61% of the eggs and 17% of the embryos were degenerating. Local injection of PGE₂ at 4 $\text{d p.c.}$ succeeded in inhibiting implantation in 95% of the eggs while 77% of the eggs failed to implant following local injection of PGF_2α at 4 $\text{d p.c.}$ Intravenous injection of PGE₂ and PGF_2α at 4 $\text{d p.c.}$ failed to disturb implantation.     

慢性子宫内膜炎中MMP-2和TIMP-2表达的研究

目的 探讨慢性子宫内膜炎患者子宫内膜中的基质金属蛋白酶-2和组织金属蛋白酶抑制物-2的表达与慢性子宫内膜炎的关系.方法 子宫内膜活检诊断为慢性子宫内膜炎者为实验组共37例,正常对照组30例,采用免疫组化链酶亲和素-生物素-过氧化物酶连接法检测两组子宫内膜基质金属蛋白酶-2和组织金属蛋白酶抑制物-2的表达.结果 实验组子宫内膜腺上皮细胞和间质细胞中基质金属蛋白酶-2和组织金属蛋白酶抑制物-2的表达均低于对照组.实验组基质金属蛋白酶-2在子宫内膜腺上皮细胞(χ2 = 15.7546,P=0.0001)和间质细胞(χ2 =8.6695,P=0.0032)的表达均低于对照组.实验组组织基质金属蛋白酶抑制物-2在子宫内膜腺上皮细胞(χ2 =21.8134,P=0.0000)和间质细胞(χ2 = 8.1883,P=0.0042)的表达也低于对照组.结论 基质金属蛋白酶-2和组织金属蛋白酶抑制物-2表达降低可能与慢性子宫内膜炎有关.     

Decompression comparison of N2 and O2 in rats

We have previously reported that O2 in the breathing gas mixture contributed significantly to the risk of decompression sickness (DCS) in rats after rapid (less than 10 s) decompression to the surface from depth. The rate of O2 uptake was extremely fast (less than 1 min estimated for equilibrium after a pressure change) compared to much slower rates for He and N2. To further define the role that O2 plays in diving, the present investigation examined decompression outcome in unanesthetized male albino rats after 60-min N2-O2 dives (1-3 atm abs O2, depth 6.26 or 7.26 atm abs). Slower decompression profiles were used to determine the elimination rates of N2 and O2 as pressure was reduced and included "stops" of up to 20 min. The probability of DCS was modeled using the maximum likelihood technique. O2 again contributed significantly to the risk of DCS, although O2 was eliminated very rapidly during decompression; the washout of N2 was considerably longer. These findings support the view that O2 can add significantly to decompression risk. However, this phenomenon may not normally be encountered during human diving operations where relatively slower decompression and lower PO2's are used.     

Synthesis and anti-inflammatory activity of N-substituted 2-oxo-2H-1-benzopyran-3-carboxamides and their 2-iminoanalogues

Aseries of N-arylsubstituted 2-imino-2H-1-benzopyran-3-carboxamides 3a and b and 2-oxo-2H-1-benzopyran-3-carboxamides 4a-h were synthesized and evaluated for their anti-inflammatory activity in carrageenan-induced rat paw oedema assays and in acetic acid-induced peritonitis tests in albino rats. The resulting products were found to be active anti-inflammatory agents and their effects were comparable to that of piroxicam as the reference compound. In the consideration of the efficacy of the compounds in these assays, 2-imino/oxo-2H-1-benzopyran-3-carboxamides 3a and b and 4a-h were further studied at graded doses for their acute toxicity (ALD(50)) in albino mice and were essentially non-toxic at the highest dose tested.     

Reproduction of aquatic hyphomycetes at low concentrations of Ca2+, Zn2+, Cu2+, and Cd2+

Maple leaf disks were conditioned in a stream for three weeks and then aerated for 2 d in distilled water to induce fungal sporulation. The release of aquatic hyphomycete spores increased when the water was supplemented with low concentrations of Ca(2+) (5 μg/L), Zn(2+) (2.5 μg/L), Cu(2+) (0.5 μg/L), or Cd(2+) (0.125 μg/L). Higher supplement concentrations inhibited sporulation. Over the concentration range used, the sporulation response was generally best described by a quadratic regression, suggesting a biphasic or hormetic response. A similar pattern was found with the number of fungal species as the dependent variable. Anguillospora filiformis and Anguillospora longissima were generally least inhibited by metal supplements, and Ca(2+) was the least and Cd(2+) the most toxic metal. Combinations of metals had a more severe effect on fungal sporulation than predicted from addition of the effects of the metals in isolation. The biological significance of the hormetic response is unclear; however, acknowledging it is clearly relevant for establishing guidelines or recommendations in toxicology.     

LV-calb2和LV-siRNA-calb2慢病毒载体的构建及其在睾丸间质细胞的表达

目的：构建钙视网膜蛋白（CALB2）基因超表达及小干扰RNA（siRNA）慢病毒载体,观察CALB2对睾丸间质细胞雄激素合成的调节作用。方法：合成超表达及干涉的质粒,转入制备好的细菌感受态细胞,聚合酶链反应（PCR）鉴定阳性重组子后测序验证,确认构建成功的超表达及干涉慢病毒载体。用上述慢病毒载体分别感染MLTC-1及R2C间质细胞,观察感染效率,而后用放射免疫法检测睾酮和孕酮的合成。结果：PCR和基因测序证实LV-calb2和LV-siRNA-calb2慢病毒载体构建成功,并可高效感染MLTC-1及R2C细胞。超表达CALB2后,MLTC-1细胞睾酮生成显著增加（P＜0.001）;干涉CALB2表达后,R2C间质细胞孕酮生成显著减少（P＜0.05）。结论：成功构建了calb2基因超表达及干涉慢病毒载体,并可体外转染睾丸间质细胞系。初步结果表明,CALB2可促进间质细胞类固醇激素生成。     

Delayed mortality of mice following inhalation of acute doses of CH2O, SO2Cl2, and Br2

Mortalities and times of death of mice were measured, during several weeks, after single respiratory exposures to air containing either of the 4 chemicals. The toxicity sequence observed, at 320 ppm, was Cl2 greater than Br2 greater than CH2O greater than SO2. For CH2O and Br2 at constant concentration, time of death depended markedly on exposure duration. The scant literature data enabled comparison of results for SO2 only.     

Synthesis,antiprotozoal and anticancer activity of substituted 2-trifluoromethyl- and 2-pentafluoroethylbenzimidazoles

The synthesis of several halogenated benzimidazoles substituted in position 2 with trifluoromethyl, pentafluoroethyl and 2-thioethylaminodimethyl group is reported. Antiprotozoal and anticancer activity of series of newly synthesized and previously obtained compounds was studied. All of tested bezimidazoles showed remarkable antiprotozoal activity against Giardia intestinalis, Entamoeba histolytica and Trichomonas vaginalis. Of the studied collection of halogenated benzimidazoles the most anticancer-active was the 5,6-dichloro-2-pentafluoroethyl compound, particularly against breast and prostate cancer cell lines.     

尾加压素Ⅱ基因多态性与2型糖尿病关系

目的 探讨尾加压素Ⅱ(UTS2)基因变异及其单倍型与2型糖尿病的关系.方法采用病例对照研究,应用聚合酶链式反应-限性性内切酶片段长度多态性(PCR-RFLP)技术,对UTS2基因多态性进行检测.结果 rs228648、rs2890565、rs228651的基因型在2组之间的分布差异有统计学意义(Prs228648＜0.001,Prs2890565=0.021,Prs228651=0.050).GACA单倍型在病例组中的频率(9.3%)显著低于对照组(20.3%,P=0.007),GGTG单倍型在病例组中的频率(4.0%)显著高于对照组(0.6%,P=0.015).标签基因(Tag SNPs)组成的单倍型GT和AT在病例组中的频率(分别为17.4%和11.1%)显著低于对照组(分别为22.6%和15.5%)(P均＜0.05).结果 rs228648(G/A)和rs228651(A/G)的位点变异与2型糖尿病的发生呈正关联,rs2890565(C/T)的TT基因型与2型糖尿病的发生成负关联.U152基因多态性及其单倍型与2型糖尿病的易感性有关.