Role of glutathione in reduction of arsenate and of gamma-glutamyltranspeptidase in disposition of arsenite in rats

Arsenate (AsV), the environmentally prevalent form of arsenic, is converted sequentially in the body to arsenite (AsIII), monomethylarsonic acid (MMAsV), monomethylarsonous acid (MMAsIII), and dimethylarsinic acid (DMAsV) and some trimethylated metabolites. Although the biliary excretion of arsenic in rats is known to be glutathione (GSH)-dependent, involving transport of arsenic-GSH conjugates, the role of GSH in the reduction of AsV to the more toxic AsIII in vivo has not been defined. Therefore, we studied how the fate of AsV is influenced by buthionine sulfoximine (BSO), which depletes GSH in tissues. Control and BSO-treated rats were given AsV (50 micromol/kg, i.v.) and arsenic metabolites in bile, urine, blood and tissues were analysed by HPLC-HG-AFS. BSO increased retention of AsV in blood and tissues and decreased appearance of AsIII in blood, bile (by 96%) and urine (by 63%). The biliary excretion of MMAsIII was also nearly abolished, the appearance of MMAsIII and MMAsV in the blood was delayed and the renal concentrations of these monomethylated arsenicals were decreased by BSO. Interestingly, appearance of DMAsV in blood and urine remained unchanged and the concentrations of this metabolite in the kidneys and muscle were even increased in response to BSO. To test the role of gamma-glutamyltranspeptidase (GGT) in arsenic disposition, the effect of the of the GGT inhibitor acivicin was investigated in rats injected with AsIII (50 micromol/kg, i.v.). Acivicin lowered the hepatic and renal GGT activities and increased the biliary as well as urinary excretion of GSH, but failed to alter the disposition (i.e. blood and tissue concentrations, biliary and urinary excretion) of AsIII and its metabolites. In conclusion, shortage of GSH decreases not only the hepatobiliary transport of arsenic, but also reduction of AsV and the formation of monomethylated arsenic, while not hindering the production of dimethylated arsenic. While GSH plays an important role in the disposition and toxicity of arsenic, GGT, which hydrolyses GSH and GSH conjugates, apparently does not influence the fate of the GSH-reactive trivalent arsenicals in rats.     

微透析取样技术在中药体内分析中的应用研究进展

本文综述了微透析取样技术在中药体内分析中的应用,介绍微透析取样技术的原理、组成、探针类型、特点,重点阐述了微透析取样技术在测定脑、血液、皮肤等组织器官中中药有效成分浓度的应用实例。表明微透析取样技术在中药药效研究中具有广阔的前景。     

应用PASS系统分析我院2010年住院医嘱

目的:了解我院2010年住院患者的合理用药情况,探讨如何利用合理用药监测系统( PASS)提高合理用药水平.方法:利用PASS对我院2010年15 966例住院患者的1 184 997条用药医嘱进行监测,以黑色警示医嘱为依据,收集不合理用药信息,并对监测结果进行统计、分析.结果:不合理用药医嘱50 261条,发生率为4.24％.绝对禁止黑色医嘱5441条,主要为药物相互作用(66.54％)、注射液体外配伍(17.86％)、用法用量(15.46％)、儿童警告(1.14％).结论:应用PASS系统能有效监测医嘱中的不合理用药情况,有利于提高临床合理用药水平,但PASS系统尚存在局限性,有待进一步完善.     

应用PASS系统对我院2008年住院医嘱的分析

目的监测分析2008年我院住院患者用药情况。方法将PASS系统嵌入医生工作站、临床药学工作站等子系统,构建合理用药计算机网络系统,对住院医嘱进行及时监测,将监测结果向医生反馈,并对其进行统计、分析。结果2008年共监测医嘱3 620 241条,不合理医嘱908条,占0.02%。不合理医嘱中,配伍禁忌(381条)占41.96%,用法用量(381条)占41.96%,药物相互作用(108条)占11.89%,儿童用药(38条)占4.19%。经与医生沟通后,更改不合理医嘱856条,占94.27%。结论PASS系统可有效监测医嘱中的不合理用药,通过与医生交流,大大减少药物不良事件的发生,值得临床推广应用,也为临床药师开展工作带来了极大的便利。但PASS系统尚存在局限性,有待进一步完善。     

Role of desacetylation in the detoxification of cephalothin in renal cells in culture

The toxicity of three cephalosporin antibiotics to rabbit kidney cells in culture was compared to their known nephrotoxic potential in vivo (cephaloridine greater than cefazolin greater than cephalothin). While cephalothin is considered to be a relatively nonnephrotoxic cephalosporin when administered to many species including humans and rabbits, in several in vitro systems involving rabbit renal tissue, cephalothin was comparatively more toxic than anticipated based on in vivo data. Cephalothin is extensively desacetylated in rabbits to a less microbiologically active metabolite, desacetylcephalothin. When a microsomal S9 fraction from rabbit kidney was added to the in vitro assay in cultured rabbit renal cells, cephalothin was desacetylated and its toxicity to kidney cells was reduced. The addition of S9 in vitro provided a toxicity ranking of the cephalosporins that correlated with their known in vivo nephrotoxic potentials (cephaloridine greater than cefazolin greater than cephalothin). The in vitro detoxification of cephalothin by S9 was blocked by the coadministration of the esterase inhibitor, aminocarb. Desacetylcephalothin was relatively nontoxic to rabbit renal tissue in vitro. These results suggest that the desacetylation of cephalothin in vivo represents a previously unrecognized mechanism of detoxification of this cephalosporin antibiotic. Furthermore, this mechanism of detoxification may be applicable to other acetylated cephalosporins.     

2009年某院住院患者抗真菌药用药调查

目的:分析讨论某院抗真菌药使用的合理性,为临床安全有效地使用抗真菌药提供参考。方法:回顾性统计分析某院2009年住院患者抗真菌药用药信息。结果:2009年某院住院患者抗真菌药DDDs排名前3名分别为:氟康唑、制霉菌素和伊曲康唑;使用金额排名前3名分别为:氟康唑、米卡芬净及卡泊芬净;更换一种抗真菌药进行治疗的患者数为176人,在全部患者中占13.4%。结论:应进一步强化用药指征的意识,提高标本送检率,同时改善某些抗真菌用药不合理更换的现象,以避免耐药性发生,从而更好更长远地体现抗真菌药的治疗价值。     

Changes in levels of dependency and predictors of mortality in elderly people in institutional care in Dunedin

The 1983 study of dependency of subjects in institutional care in Dunedin was repeated two years later. A significant increase in levels of dependency in residential homes, particularly in the Religious and Welfare sector was found. In 1983 there were 29 high dependency residents and 73 medium dependency residents in residential homes. In 1985 these numbers had increased to 55 and 86 respectively. There was no change in the number of low dependency residents. In 1983, 6 high dependency residents had been admitted to residential home care in the year prior to the study. In 1985 the number of high dependency residents recently admitted had increased to 23. There had also been a significant increase in the dependency of patients in Religious and Welfare continuing care hospitals. Of the 933 subjects in institutional care in 1983 who were able to be followed, 354 (37.9%) died in the following 2 years. Mortality rate was higher for those in hospital care (48.1%) than for those in residential home care (29.6%). Mortality rates were higher in more dependent subjects and this was evident for each measure of dependency.     

Kinetics of in vitro metabolism of methoxyphenamine in rats

1. Methoxyphenamine (MP) was metabolized in vitro by rat liver preparations to O-desmethylmethoxyphenamine (O-desmethyl-MP), N-desmethylmethoxyphenamine (N-desmethyl-MP) and 5-hydroxymethoxyphenamine (5-hydroxy-MP). These metabolic pathways were inhibited by SKF 525-A and carbon monoxide, which indicates that these reactions were mediated at least partly by an NADPH-dependent cytochrome P-450 system. 2. Strain differences in the metabolism of this drug in vitro were observed in female Lewis and Dark Agouti (DA) rats, which are proposed models for human debrisoquine phenotypes. Methoxyphenamine O-demethylase and 5-hydroxylase activity in DA rats were lower than those in Lewis rats. 3. The metabolic transformation of methoxyphenamine in vitro to O-desmethyl-MP was inhibited competitively by debrisoquine and sparteine. This indicates that the cytochrome P-450 isoenzyme mediating the metabolism of MP to O-desmethyl-MP is similar to that mediating metabolism of debrisoquine and sparteine. However, no inhibition was observed with methenytoin.     

基层医院护士在临床合理用药中的作用

目的充分利用护士在医师和患者间的特殊地位和作用,促进基层临床合理用药。方法从护士的工作性质出发,论述护士参与促进合理用药的方便和优势。结果通过实践,护士在促进合理用药中的作用得到有效发挥,基层合理用药环境得到极大改善。结论充分利用护士与医师和患者间的特殊桥梁作用,在基层医院促进合理用药,规范医师用药行为,防止药物滥用,引导患者安全用药,降低药源性疾病。     

Comparison of in vivo and in vitro toxic effects of microcystin-LR in fasted rats

The toxic effects of microcystin-LR, a cyclic heptapeptide isolated from the cyanobacterium Microcystis aeruginosa, were studied in the fasted rat model and in subcellular fractions from fasted, toxin-treated and control rats. Hepatotoxic effects of a lethal dose (100 micrograms/kg) were examined 15-90 min post-injection. Elevations of serum enzymes, particularly sorbitol dehydrogenase, specific for liver mitochondria, correlated with hepatic damage. Electron micrographs showed progressive cellular disruption, including dilation of rough endoplasmic reticulum, incorporation of cellular components into cytolysosomes, hydropic mitochondria devoid of electron-opaque deposits, loss of desmosome-associated intermediate filaments, disruption of sinusoidal architecture and, ultimately, lysis of hepatocytes. The appearance of hydropic mitochondria correlated with loss of coupled electron transport. Changes in plasma membrane-associated cytoskeletal filaments correlated with loss of desmosome tonofilaments. In contrast to in vivo exposure to microcystin-LR, in vitro exposure to toxin had no effect on mitochondria or cytoskeletal filaments, suggesting that the toxic effects observed in vivo were indirect and may be dependent on bioactivation of the toxin or a cascade of events not supported in in vitro models.     

Comparison of in vitro cell models in predicting in vivo brain entry of drugs

Although several in vitro models have been reported to predict the ability of drug candidates to cross the blood-brain barrier, their real in vivo relevance has rarely been evaluated. The present study demonstrates the in vivo relevance of simple unidirectional permeability coefficient (P(app)) determined in three in vitro cell models (BBMEC, Caco-2 and MDCKII-MDR1) for nine model drugs (alprenolol, atenolol, metoprolol, pindolol, entacapone, tolcapone, baclofen, midazolam and ondansetron) by using dual probe microdialysis in the rat brain and blood as an in vivo measure. There was a clear correlation between the P(app) and the unbound brain/blood ratios determined by in vivo microdialysis (BBMEC r=0.99, Caco-2 r=0.91 and MDCKII-MDR1 r=0.85). Despite of the substantial differences in the absolute in vitro P(app) values and regardless of the method used (side-by-side vs. filter insert system), the capability of the in vitro models to rank order drugs was similar. By this approach, thus, the additional value offered by the true endothelial cell model (BBMEC) remains obscure. The present results also highlight the need of both in vitro as well as in vivo methods in characterization of blood-brain barrier passage of new drug candidates.     

Study of potential in vitro and in vivo genotoxicity in hepatocytes of quinolone antibiotics

The genotoxicity of quinolone antibiotics has been evaluated in hepatocytes following in vitro and in vivo exposure. Unscheduled DNA synthesis (UDS) was induced in vitro in rat hepatocytes by norfloxacin, ofloxacin, pefloxacin, and ciprofloxacin but not by nalidixic acid. In vivo UDS was not observed in hepatocytes isolated 4 to 24 hr after exposure of adult male F344 rats to either a single dose (30 to 190 mg/kg) or repeated doses (40 mg/kg) of ciprofloxacin. Using the 32P-postlabeling technique, no modified bases were detected in hepatocytes exposed in vitro to ciprofloxacin. In summary, UDS was induced in hepatocytes by in vitro exposure to high concentrations of norfloxacin, ofloxacin, pefloxacin, or ciprofloxacin. There was no evidence of in vitro DNA adduct formation by ciprofloxacin or in vivo DNA damage under the conditions tested. These findings suggest that ciprofloxacin is not DNA reactive, but it induces in vitro UDS as a consequence of some indirect action.     

Chondroprotective Effects of Wogonin in Experimental Models of Osteoarthritis in vitro and in vivo

We evaluated the chondroprotective effects of wogonin by investigating its effects on the gene expression and production of matrix metalloproteinase-3 (MMP-3) in primary cultured rabbit articular chondrocytes, as well as on production of MMP-3 in the rat knee. Rabbit articular chondrocytes were cultured in a monolayer, and RT-PCR was used to measure interleukin-1β (IL-1β)-induced expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), and type II collagen. In rabbit articular chondrocytes, the effects of wogonin on IL-1β-induced production and proteolytic activity of MMP-3 were investigated using western blot analysis and casein zymography, respectively. The effect of wogonin on MMP-3 protein production was also examined in vivo. In rabbit articular chondrocytes, wogonin inhibited the expression of MMP-3, MMP-1, MMP-13, and ADAMTS-4, but increased expression of type II collagen. Furthermore, wogonin inhibited the production and proteolytic activity of MMP-3 in vitro, and inhibited production of MMP-3 protein in vivo. These results suggest that wogonin can regulate the gene expression and production of MMP-3, by directly acting on articular chondrocytes.     

合肥市某“三甲医院”2009年住院患者抗菌药物应用分析

目的:分析该"三甲"医院2009年住院患者抗菌药物的使用情况,为临床合理使用抗菌药物提供参考。方法:收集该"三甲"医院2009年抗菌药物使用资料,并对抗菌药物应用的品种、销售金额和用药频度(DDDs)等进行分析。结果:住院患者使用抗菌药物涉及96种,销售金额(4597.57万元)占医院药品销售总金额(15123.58万元)的30.40%,其中列前3位的依次为头孢菌素类28种(2386.49万元),其他β-内酰胺类16种(1124.52万元)及氟喹诺酮类8种(319.03万元);用药金额与用药频度(DDDs)前3位为头孢甲肟、头孢替安、头孢孟多酯。结论:该院住院患者抗菌药物应用结构基本合理,但仍应重视其安全性、有效性,合理选择使用。     

关于中国药典巴戟天项下应增加菊糖检查的建议

巴戟天为茜草科植物巴戟天 Morinda offici-nalis How 的干燥根。我们最近在检验工作中发现,有些正品巴戟天的薄壁细胞中有菊糖存在。经查阅大量有关文献资料及历版《中国药典》,均未记载其含有菊糖,这给药品检验工作带来了困难,且有的文献报道将不含有菊糖作为鉴定正品巴戟天与其主要伪品同科植物四川虎刺 Damnacanthus offici-narum Huang 的主要区别点,这更混淆了巴戟天的鉴定。     

西南4省市63家医院2002年呼吸系统用药分析

目的 :分析 2 0 0 2年西南 4省市 6 3家医院呼吸系统用药的现状及趋势。方法 :收集 2 0 0 2年西南 4省市 6 3家医院的呼吸系统类药物的用药数据 ,对其每季度用药金额、用药品种及生产公司进行调查。结果 :2 0 0 2年呼吸系统用药金额为 3345 1786元 ,1季度～ 4季度用药金额分别为全年用药金额的 19 7%、19 3%、2 7 0 %和 34 0 % ;止咳祛痰药占总用药金额的 5 9 4 % ,平喘药占总用药金额的 4 0 6 % ,氨溴索和卡提素两种药物占用药金额的 5 1 4 7% ,国外公司生产及进口药品用药金额约占 2 7%。结论 :呼吸系统用药随季节而变化 ,冬秋季节呼吸系统用药金额明显大于春、夏季节     

罗哌卡因在分娩镇痛中的应用

目的：观察不同浓度罗哌卡因（ropivacaine,Rop)用于分娩镇痛的临床效果,探索其理想的浓度和剂量。方法：随机选择ASAⅠ-Ⅱ级临产初产妇45例,平均分为三组：0．16％Rop组和0．2%Rop组作为观察组,以及对照组15例。观察组于宫口开至2－3cm时于L2－3间隙行硬膜外腔穿刺置管,以罗哌卡因维持镇痛;对照组未作分娩镇痛。围分娩镇痛期地监测血压（BP）、脉氧饱和度（SpO2)、EKG、PETCO2、宫缩及胎心音,记录产程时间：镇痛效果采用VAPS评分法进行疼痛评分,运动神经阻滞以Bromage分级评分;新生儿出生后1－5min进行Apgar评分,分娩后24h新生儿NACS评分。结果：围分娩期三组生命体征稳定;VAPS评分观察组较对照组明显降低,但0．2％Rop对运动神经的阻滞频率和程度最重,对宫缩有轻微的抑制,催产素用量相对增加;对产的影响均短于对照组,但差异不显著,三组对围分娩期胎心、Apgar评分无影响;分娩后24hNACS评分观察组较对照组增高明显;剖宫产率0．16％、Rop组最低。结论：罗哌卡因独特的感觉和运动阻滞明显分离,对子宫胎盘血流无明显影响,有利于分娩镇痛。0．2％Rop较0．16％对运动神经阻滞的频率和程度更重0．16％Rop对分娩镇痛是一种比较理想的局部麻醉药。     

舒乐洗剂治疗外阴阴道念珠菌病的体内外实验研究

目的：观察舒乐洗剂治疗外阴阴道念珠菌病（VVC）的效果。方法建立体外白念珠菌生物膜模型,采用 XTT 法检测生物膜抑制率;建立 VVC 小鼠模型,采用阴道涂片检查和病理组织检测法,比较给药前后炎症状况的变化。结果舒乐洗剂对体外白念珠菌生物膜的形成有明显抑制作用,并成一定的剂量依赖性;能够抑制体外白念珠菌菌落形成,其中原液稀释一倍的效果最为显著;能够明显减少小鼠体内白念珠菌菌落形成,并能够减少炎性细胞向阴道黏膜的浸润。结论舒乐洗剂具有体外抗生物膜形成的作用,并能降低体内小鼠白念珠菌的感染状况,减轻VVC 小鼠阴道黏膜炎症,从而达到治疗 VVC 的作用。