小檗碱对人肝癌细胞系SMMC-7721细胞增殖和凋亡的影响

目的 探讨小檗碱对人肝癌细胞系SMMC-7721细胞株增殖和凋亡的作用.方法 应用MTT、流式细胞仪和软琼脂克隆形成试验,研究小檗碱对人肝癌细胞系SMMC-7721细胞株增殖和凋亡的作用.结果 小檗碱对人肝癌细胞株SMMC-7721细胞有抑制增殖、促进凋亡和抑制细胞克隆形成能力.结论 小檗碱对人肝癌细胞系SMMC-7721细胞有抑制增殖和促进凋亡作用.     

氯化两面针碱在体外对肝细胞L-O2和肾细胞293增殖的影响

目的:观察氯化两面针碱在体外对人胃癌细胞7901、人鼻咽癌细胞cne1-1、人肾癌细胞ketr-3、人肝癌细胞BEL 7404的增殖抑制作用和对人胚肝细胞L-O2和人胚肾细胞293的增殖影响。方法:采用MTT法检测不同浓度氯化两面针碱对4种肿瘤细胞和人胚肝细胞L-O2及人胚肾细胞293增殖的影响,比较其IC50值;采用紫外分光光度法测定氯化两面针碱作用后肝、肾细胞培养上清液中SOD,MDA,LDH值的变化。结果:氯化两面针碱在体外对肿瘤细胞具有较强的增殖抑制作用,同时对人胚肝细胞L-O2和人胚肾细胞293有一定的增殖抑制作用。结论:氯化两面针碱能抑制多种肿瘤细胞的增殖,对肿瘤细胞有明显细胞毒性作用,同时可抑制人胚肝细胞L-O2和人胚肾细胞293的增殖,对人体肝、肾细胞有一定的毒性。     

肿瘤坏死因子α对人肝癌细胞株SMMC-7721体外侵袭能力的影响

目的 探讨肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)对人肝癌细胞株SMMC-7721体外侵袭能力的影响及其相关机制. 方法不同浓度TNF-α作用于人肝癌细胞株SMMC-7721后,采用Transwell试验检测细胞侵袭能力的改变,采用划痕标记荧光传输试验显示缝隙连接细胞通讯功能的变化,采用Western blot法检测连接蛋白32(Cx32)在细胞膜的表达. 结果 不同浓度TNF-α作用于人肝癌细胞株SMMC-7721后,Transwell试验显示细胞侵袭能力较对照组提高,且随TNF-α浓度增加而升高. 同时,缝隙连接细胞通讯功能减弱,细胞膜上Cx32的表达减少. 结论 TNF-α可能通过影响Cx32在细胞膜的表达及细胞通讯促进人肝癌细胞株SMMC-7721的侵袭能力.     

莲房花青素诱导人肝癌细胞SMMC-7721凋亡的研究

目的研究莲房花青素对人肝癌细胞株SMMC-7721凋亡的影响,探讨其抗癌机制。方法以不同浓度的莲房花青素(LSPC)与人肝癌细胞株SMMC-7721细胞共培养,MTT法测定细胞增殖。结果 LSPC可体外抑制肝癌细胞生长,抑制率呈浓度和时间依赖性并随浓度增加而增高。结论莲房原花青素(LSPC)可能通过诱导细胞凋亡抑制人肝癌细胞增殖。     

蜗牛多糖对人肝癌细胞SMMC-7721的抑制作用

目的 探讨蜗牛多糖对人肝癌细胞株SMMC-7721的抑制作用. 方法将不同浓度的蜗牛多糖分别与人肝癌细胞SMMC-7721共同培养24,48,72 h后,采用噻唑蓝法测定吸光度值(A),评定蜗牛多糖对肝癌细胞株的增殖抑制作用;流式细胞术测定其对肝癌细胞周期的影响. 结果 不同浓度的蜗牛多糖作用SMMC-7721细胞24,48和72 h后,各组与细胞对照组比较,A值差异有统计学意义(P<0.05或P<0.01),并显示出对时间和剂量的依赖性,蜗牛多糖对SMMC-7721细胞的半数抑制浓度分别为0.293,0.032和0.011 mg.mL^-1. 流式细胞术结果 表明,蜗牛多糖能将肝癌细胞株SMMC-7721阻滞在细胞的G2/M期. 结论 蜗牛多糖对肝癌细胞株SMMC-7721的增殖有一定的抑制作用.     

白藜芦醇对人肝癌细胞株SMMC-7721增殖和凋亡的影响

目的观察白藜芦醇对人肝癌细胞株SMMC-7721增殖和凋亡的影响,并初步探讨其机制。方法用MTT法检测白藜芦醇对SMMC-7721细胞增殖影响的量效与时效关系;应用流式细胞术（FCM）检测细胞凋亡率;比色法测定caspase-3酶活性。结果白藜芦醇（50、100、200μmol·L^-1）处理SMMC-7721细胞48h,呈浓度依赖性抑制SMMC-7721细胞增殖且诱导其凋亡;100μmol·L^-1白藜芦醇处理细胞24、48或72h显著抑制SMMC-7721细胞增殖并诱导其凋亡,且呈时间依赖性。白藜芦醇（50、100、200μmol·L^-1）处理SMMC-7721细胞48h,呈浓度依赖性增加SMMC-7721细胞caspase-3活性。结论白藜芦醇可抑制人肝癌细胞株洲C-7721的增殖,诱导细胞凋亡,其机制与增强细胞内caspase-3活性有关。     

川芎嗪对肝癌多药耐药株SMMC-7721/ADM的逆转作用

目的 研究川芎嗪对肝癌多药耐药株SMMC-7721／ADM的逆转及其机制。方法 用MTT法检测常用化疗药物对SMMC-7721／ADM的毒性。用流式细胞仪(FCM)检测SMMC-7721／ADM细胞表面P-糖蛋白(P-gp)的表达及细胞内柔红霉素的相对浓度。结果 川芎嗪可提高SMMC-7721／ADM细胞内化疗药物的浓度,增加阿霉素等化疗药物对SMMC-7721／ADM的毒性作用。结论 川芎嗪可逆转人肝癌多药耐药株SMMC-7721／ADM,其机制可能与胞内ADM浓度有关。     

氯化两面针碱通过甲基化率调控p53和E2F介导肝癌POLD1基因表达的初步研究

探讨氯化两面针碱(Nitidine chloride,NC)通过影响POLD1基因启动子甲基化率及调节转录调控因子p53和E2F的特异性结合对肝癌SMMC-7721细胞增殖和凋亡的影响。该研究采用CCK8,焦磷酸测序,RT-PCR,Western blot等技术方法论证了NC通过影响POLD1基因启动子甲基化率,间接调控POLD1基因转录活性,从而降低了DNA聚合酶δ的合成效率,抑制肝癌SMMC-7721细胞的增殖。不同剂量的NC(0.5,1.0,2.0 mg/m L)处理肝癌细胞SMMC-7721 48 h后,细胞增殖抑制率逐渐增大,分别为21.1%,35.2%,92.1%,呈明显的剂量依赖性。POLD1基因启动子的甲基化水平整体上升。经方差分析,与对照组相比,1.0,2.0 mg/m L实验组的E2F结合位点甲基化率随浓度增加而增高(F=10.21,P<0.05),差异有统计学意义,0.5 mg/m L实验组与对照组相比无明显差异(P=0.694)。而p53结合位点甲基化率随NC浓度增加呈下降趋势,实验组与对照组有明显差异(F=9.76,P<0.05),其中2.0 mg/m L实验组有显著差异(P<0.01)。实验组POLD1 mRNA和蛋白p125随NC浓度增加而下降,采用秩和检验,X2分别为40.19,36.65,P<0.05,1.0、2.0 mg/m L实验组与对照组相比,差异有统计学意义。结果显示氯化两面针碱可能通过调节SMMC-7721细胞POLD1基因的甲基化水平,影响其启动子转录调控因子的作用,从而抑制了POLD1基因表达,降低DNA聚合酶δ活性,抑制肝癌细胞增殖的作用。     

三氧化二砷对肝癌细胞内活性氧水平的影响

目的探讨三氧化二砷（As2O3）对肝癌细胞增殖及细胞内活性氧（ROS）水平的影响。方法用As2O3作用于体外培养的人肝癌SMMC-7721细胞株，分别用MTT法和流式细胞仪观察SMMC-7721细胞增殖情况并检测ROS。结果MTT结果显示As2O3能明显抑制SMMC-7721细胞的增殖．并呈时间和浓度依赖性。流式细胞仪分析显示As2O3作用后的人肝癌SMMC-7721细胞内ROS水平明显增高（P〈0．01）．并也呈时间和浓度依赖性。结论As2O3可通过抑制人肝癌SMMC-7721细胞的增殖和提高细胞内ROS水平诱导细胞凋亡而发挥抗肿瘤作用，这可能也是As2O3抗肝癌的主要途径之一。     

白芍总苷对SMMC-7721细胞增殖的抑制作用

目的探讨白芍总苷(total glucosides of paeony,TGP)对人肝癌细胞株SMMC-7721的增殖抑制作用及其机制。方法采用MTT法检测TGP对SMMC-7721增殖的影响;应用荧光显微镜观察药物作用后的细胞的形态。结果白芍总苷(0.5~2.5g.L-1)能抑制SMMC-7721细胞生长,且呈浓度依赖性;TGP(1.0、1.5 g.L-1)分别作用72 h后,SMMC-7721细胞出现体积缩小,荧光染色增强,胞核或胞质中可见致密浓染的块状或颗粒状黄绿色荧光染色。结论白芍总苷在体外能够抑制人肝癌细胞SMMC-7721的增殖,并能诱导细胞凋亡。     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg.kg) or i.p. (50 mg.kg) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) l.h. kg in the male rat and 10.6 (95% CI: 7.5, 15.0) l.h. kg in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p 0.001) in plasma obtained from the male (8.8 2.0%) compared with the female rat (11.7 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg x kg(-1)) or i.p. (50 mg x kg(-1)) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) 1 x h(-1) x kg(-1) in the male rat and 10.6 (95% CI: 7.5, 15.0) 1 x h(-1) x kg(-1) in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was approximately 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p < 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p < 0.001) in plasma obtained from the male (8.8 +/- 2.0%) compared with the female rat (11.7 +/- 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Theophylline kinetics in peripheral tissues in vivo in humans

Several biochemical and cellular effects have been described for methylxanthines under in vitro conditions. However, it is unknown, whether threshold concentrations required to exert these effects are attained in target tissues in vivo. We therefore employed the microdialysis technique for measuring theophylline concentrations in peripheral tissues under in vivo conditions.Following in vitro and in vivo calibration, microdialysis probes were inserted into the medial vastus muscle and into the periumbilical subcutaneous adipose layer of healthy volunteers. Following single oral dose administration of 300 mg or i.v. infusion of 240 mg theophylline, in vivo time courses of theophylline concentrations were monitored in tissues and plasma. Major pharmacokinetic parameters (c_max, t_max, AUC) were calculated for plasma and tissue time courses. The mean AUC_tissue /AUC_plasma-ratio was 0.56 (p.o.) and 0.55 (i.v.) for muscle and 0.55 (p.o.) and 0.72 (i.v.) for subcutaneous adipose tissue.We conclude that microdialysis provides important information on the distribution and the tissue pharmacokinetics of theophylline.Abbreviations FPIA Fluorescence polarisation immuno assay - AUC Area under the curve - t_max Time to peak concentration - c_max Peak concentration     

休克时血中氧自由基的变化

本实验测定10名休克患者血浆和红细胞的丙二醛(MDA)、血浆总抗的氧化活性(AOA)的含量。结果表明:休克病人红细胞膜和血浆 MDA 含量(4.298±0.722;5.348±0.834)与对照组(3.235±0.682;4.356±1.081)比较明显增高(P<0.05);血浆 AOA(39.65±7.858)与对照组(48.21±10.81)比较明显降低(P<0.01)。提示:休克时,患者机体内自由基反应增强是引起组织细胞损伤的原因之一。     

Interindividual variability in metabolic activation in humans in vivo

In assessing interindividual variability in metabolic activation, the toxic metabolite is often too unstable for conventional analysis. Possible alternatives include a stable product of the reactive metabolite e.g. cysteinyl derivatives of N-acetyl-4-benzoquinoneimine, the toxic metabolite of paracetamol, adducts with DNA or protein, and indirect measurement of the activity of the enzyme(s) producing the active metabolite. An example of the last approach is the use of furafylline, a highly specific inhibitor of human CYP1A2, to determine the extent of the metabolic activation of the cooked food mutagens PhIP and MeIQx. The extent of inhibition, determined from levels of unchanged amine in urine, is an indirect measure of the activity of the activation pathway. Further refinement of this approach, allied to improved measures of the biological process of interest should prove of value in evaluating interindividual variability and its role in the risk assessment process.     

Changes in angiopoietin expression in glomeruli involved in glomerulosclerosis in rats with daunorubicin-induced nephrosis

AIM: To study the potential pathological role of endogenous angiopoietins in daunorubicin-induced progressive glomerulosclerosis in rats. METHODS: Seventy male Wistar rats were allocated randomly into a daunorubicin group (DRB; n=40) or a control group (n=30). The rats in the DRB group were injected with DRB (15 mg/kg), in their tails. Subsequently, at intervals of 1, 2, 4, 6, 8, and 12 weeks, 5 male Wistar rats in each group were chosen randomly for 24 h urinary protein quantitative measurements (24 h UPQM), and determination of plasma tumor necrosis factor alpha (TNF-alpha), angiopoietin-1 (Ang1), and angiopoietin-2 (Ang2) levels. Kidney sections were examined by electron microscopy, Periodic Acid Schiff (PAS) staining, immunohistochemical staining and in situ hybridization histochemistry. RESULTS: As glomerulosclerosis progressed in the DRB group, expression of Ang1 mRNA and protein in glomeruli decreased and expression of TNF-alpha protein, Ang2 mRNA and protein in glomeruli increased. Expression of Ang1 mRNA and protein in glomeruli were negatively correlated with 24 h UPQM, Fn protein expression, and mean area of extracellular matrix (MAECM). In comparison, expression of Ang2 mRNA and protein in glomeruli were positively correlated with 24 h UPQM, Fn protein expression and MAECM; furthermore, there was a positive correlation between plasma Ang2 and 24 h UPQM. Plasma TNF-alpha and expression of TNF-alpha in glomeruli were positively correlated with expression of Ang2 mRNA and protein in glomeruli. There was a negative correlation between Ang1 protein expression and Ang2 protein expression in glomeruli. CONCLUSION: During DRB-induced glomerulosclerosis, podocyte injury led to a shift in the balance of Ang1 and Ang2 in glomeruli. Increased TNF-alpha in plasma and glomeruli may upregulate Ang2 expression in glomeruli. Elevated Ang2 in both plasma and glomeruli may mediate protein permeability through the glomerular filtration barrier. Moreover, local expression of Ang2 may facilitate the progress of glomerulosclerosis by upregulating a component expression of extracellular matrix.     

Hyperkalaemia in patients in hospital

A survey of all laboratory blood specimens with a plasma potassium concentration greater than or equal to 5.5 mmol/L was conducted over a three month period. Of 331 specimens with hyperkalaemia, 71 were excluded because the specimens was haemolysed, old or contaminated. The laboratory served a population of 348,561 and during this time measured the plasma potassium on 25,016 occasions. Sixty-six outpatients and 20 neonates were not evaluated. The survey was undertaken on 86 of 102 inpatients (46 males), 48 of whom were over 66 years of age. Fifty-seven patients were admitted under a medical service and 29 under a surgical service. Fifty-nine had a single episode of hyperkalaemia. Thirty-two underwent a surgical procedure. The commonest contributing factor was impaired renal function which was present in 71 (83%) patients. Although a definitive causative role for drugs could be identified in only five patients, in 52 (60%) patients drugs were a contributing factor (potassium supplements 24, ACE inhibitors 16, nonsteroidal antiinflammatory drugs 12). Thirty-five of the 86 (41%) patients died during their hospital admission. Nineteen of the 35 deaths occurred within three days of the hyperkalaemia being recorded. A normal plasma potassium was eventually documented in 50 of the 86 patients. Of the remaining 36 patients, 25 (69%) subsequently died. In general the treatment of patients with hyperkalaemia focused on identifying and treating the underlying cause. Hyperkalaemia must always be considered seriously and regard given to the overall clinical status of the patient, with particular attention to drug therapy, renal and cardiac function, acid base status and the possibility of sepsis.