Definitions of antiretroviral treatment failure for measuring quality outcomes

Objectives

Our aim was to compare three different definitions of treatment failure and discuss their use as quality outcome measures for a clinical service.

Methods

Data for treatment‐naïve patients who attended the Melbourne Sexual Health Centre (MSHC) between 1 January 2000 and 31 December 2008 were analysed. Definition 1 was the strict Food and Drug Administration (FDA) definition of treatment failure as determined using the time to loss of virological response (TLOVR) algorithm. Definition 2 defined treatment failure as occurring in those whose viral load never fell to <400 HIV‐1 RNA copies/mL or who developed two consecutive viral loads ≥400 copies/mL on any treatment (switching or stopping treatment with a viral load <400 copies/mL was permitted). Definition 3 was the same as definition 2 except that individuals were also deemed to have failed if they stopped treatment for 6 months or longer.

Results

There were 310 antiretroviral‐naïve patients who started treatment in the study period. Of these, 156 [50.3%; 95% confidence interval (CI) 42.1–53.3%] experienced treatment failure under definition 1, 10 (3.2%; 95% CI 1.5–5.8%) experienced treatment failure under definition 2, and 16 (4.5%; 95% CI 2.5–7.4%) experienced treatment failure under definition 3 over the 108 months of follow‐up. The probability of failing definition 1 was statistically different from the probability of failing definition 2 or 3 (P=0.01).

Conclusion

There were significant differences in treatment failure for the three definitions. If definition 1 were used, the outcomes would be sufficiently common to enable clinics to be compared but would be less meaningful. If definition 2 or 3 were used, the events would be too rare to enable clinics to be compared, but it would be possible to set a benchmark level of success that clinics could aim to reach.     

Emergency department utilization among HIV‐infected patients in a multisite multistate study*

Objective

The aim of this study was to examine Emergency Department (ED) utilization and clinical and sociodemographic correlates of ED use among HIV‐infected patients.

Methods

During 2003, 951 patients participated in face‐to‐face interviews at 14 HIV clinics in the HIV Research Network. Respondents reported the number of ED visits in the preceding 6 months. Using logistic regression, we identified factors associated with visiting the ED in the last 6 months and admission to the hospital from the ED.

Results

Thirty‐two per cent of respondents reported at least one ED visit in the last 6 months. In multivariate analysis, any ED use was associated with Medicaid insurance, high levels of pain (the third or fourth quartile), more than seven primary care visits in the last 6 months, current or former illicit drug use, social alcohol use and female gender. Of those who used ED services, 39% reported at least one admission to the hospital. Patients with pain in the highest quartile reported increased admission rates from the ED as did those who made six or seven primary care visits, or more than seven primary care visits vs. three or fewer.

Conclusions

The likelihood of visiting the ED has not diminished since the advent of highly active antiretroviral therapy (HAART). More ED visits are to treat illnesses not related to HIV or injuries than to treat direct sequelae of HIV infection. With the growing prevalence of people living with HIV infection, the numbers of HIV‐infected patients visiting the ED may increase, and ED providers need to understand potential complications produced by HIV disease.     

Treatment of reducible unstable fractures of the distal radius in adults: a randomised controlled trial of De Palma percutaneous pinning versus bridging external fixation

Background  

At present, there is no conclusive evidence regarding the best treatment method for reducible unstable fractures of the distal radius. This study compared the effectiveness of two methods used in surgical treatment of such fractures: percutaneous pinning and external fixation.     

Transport of diclofenac by breast cancer resistance protein (ABCG2) and stimulation of multidrug resistance protein 2 (ABCC2)-mediated drug transport by diclofenac and benzbromarone

Diclofenac is an important analgesic and anti-inflammatory drug, widely used for treatment of postoperative pain, rheumatoid arthritis, and chronic pain associated with cancer. Consequently, diclofenac is often used in combination regimens and undesirable drug-drug interactions may occur. Because many drug-drug interactions may occur at the level of drug transporting proteins, we studied interactions of diclofenac with apical ATP-binding cassette (ABC) multidrug efflux transporters. Using Madin-Darby canine kidney (MDCK)-II cells transfected with human P-glycoprotein (P-gp; MDR1/ABCB1), multidrug resistance protein 2 (MRP2/ABCC2), and breast cancer resistance protein (BCRP/ABCG2) and murine Bcrp1, we found that diclofenac was efficiently transported by murine Bcrp1 and moderately by human BCRP but not by P-gp or MRP2. Furthermore, in Sf9-BCRP membrane vesicles diclofenac inhibited transport of methotrexate in a concentration-dependent manner. We next used MDCK-II-MRP2 cells to study interactions of diclofenac with MRP2-mediated drug transport. Diclofenac stimulated paclitaxel, docetaxel, and saquinavir transport at only 50 microM. We further found that the uricosuric drug benzbromarone stimulated MRP2 at an even lower concentration, having maximal stimulatory activity at only 2 microM. Diclofenac and benzbromarone stimulated MRP2-mediated transport of amphipathic lipophilic drugs at 10- and 250-fold lower concentrations, respectively, than reported for other MRP2 stimulators. Because these concentrations are readily achieved in patients, adverse drug-drug interactions may occur, for example, during cancer therapy, in which drug concentrations are often critical and stimulation of elimination via MRP2 may result in suboptimal chemotherapeutic drug concentrations. Moreover, stimulation of MRP2 activity in tumors may lead to increased efflux of chemotherapeutic drugs and thereby drug resistance.     

Role of NADPH-cytochrome P450 reductase and cytochrome-b5/NADH-b5 reductase in variability of CYP3A activity in human liver microsomes

NADPH-cytochrome P450 reductase (CPR) and cytochrome-b(5) (b(5)) together with NADH-b(5) reductase (b(5)R) play important roles in cytochrome P450 3A-mediated drug metabolism via electron transfer. However, it is not clear whether variability in expression of these accessory proteins contributes to the known interindividual variability in CYP3A activity. CPR and b(5) were measured in human liver microsomes (HLMs) by spectrophotometry and immunoblotting. HLMs from elderly (>or=46 years) male donors (n=11) averaged 27% (P=0.034) and 41% (P=0.011) lower CPR levels than young (相似文献   

信号转导子与转录激活子3在豚鼠形觉剥夺性近视发展中的表达特征

目的:观察高度近视眼眼球后壁组织信号转导子与转录激活子3的动态表达及意义。方法:实验于2005-10/2006-08在郑州大学基础医学院完成。选用健康1周龄豚鼠30只,雌雄不拘,无眼部疾患,实验前对豚鼠进行检影验光,排除先天性近视。右眼遮盖作为实验组,将直径为15mm的半透明眼罩用502胶粘于豚鼠眼周围的皮肤上,分别以1,3,6周3个不同时间点持续遮盖,每个时间点10只。左眼不做任何处理作为对照组。两组均采用检影验光检测屈光度;眼科A超测定眼轴长度;对两组3个时间点眼球后壁行S-P法免疫组织化学染色,检测信号转导子与转录激活子3的动态表达。结果:纳入豚鼠30只,均进入结果分析,模型制备过程无眼罩脱落。①生后1周豚鼠均呈远视状态,眼轴短;随时间延长,对照组远视度数减低,眼轴延长;实验组由实验前远视眼快速演变为高度近视眼,并随遮盖时间延长,近视度数加深,眼轴延长,两组之间实验前眼屈光度数、眼轴长度无明显差异(P>0.05)。实验组形觉剥夺后,两组之间眼屈光度数、眼轴长度进行比较,差异有非常显著性意义(P<0.01)。②视网膜光感受器外节、色素上皮-脉络膜均有信号转导子与转录激活子3阳性表达、巩膜弱阳性表达;而对照组表达主要位于神经节细胞,随出生时间延长,两组信号转导子与转录激活子3表达均逐渐下调。与对照组相比,实验组信号转导子与转录激活子3表达明显上调,但两组之间比较,自实验第1周开始,实验组信号转导子与转录激活子3较对照组明显上调,差异有显著性意义(P<0.01)。结论:形觉剥夺可导致高度近视;在近视中信号转导子与转录激活子3表达主要位于视网膜光感受器外节、色素上皮层和脉络膜,可能参与了近视眼的形成与发展。     

化学—酶法立体控制合成光学纯L-羟基苯丙氦酸的新方法

Optically pure L-3(2-hydroxyphenyl) alanine(L-o-tyrosine ,Ⅲa,),L-3-(3-hydroxyphenyl) alanine(L-m-tyrosine,Ⅲb )and L-3-(4-hydroxyphenyl )alanine(L-p-tyrosine,Ⅲc )were synthesized by the stereocontrolled amination of corresponding hydroxycinnamic acld(Ⅱ)catalyzed by L-phenylalanine ammonia-lyase(PAL,EC4.3.1.5 )contained in Rhodoterula rubramycelium. The amination of compound Ⅱ was completed in aqueous ammonia solution( 6.4mol·L^-1,pH10.5, 30℃) with the conversion of 74.9%(Ⅱa),21.1%(Ⅱb)and 20.6%(Ⅱc)respectively.The absolute configuration of the products Ⅲa～c were confirmed by circular dichroism(CD),and chiral high-performance ligand exchange chromatography(HPLEC)showed that productsⅢ were optically pure L-isomers.     

蛇毒中鞣花酸类及三萜类成分研究

自蛇毒（ＤｕｃｈｅｓｎｅａｉｎｄｉｃａＦｏｃｋ）全草中分离出６个化合物，其中，２个为新化合物，分别命名为蛇莓甙Ａ（ｄｕｃｈｅｓｉｄｅＡ）和蛇莓甙Ｂ（ｄｕｃｈｅｓｉｄｅＢ），经化学及光谱（ＵＶ，１Ｒ，１ＨＮＭＲ，１３ＣＮＭＲ，ＮＯＥＤＳ和ＭＳ）分析确定，蛇莓甙Ａ的结构为３＇－Ｏ－甲基－鞣花酸－４－Ｏ－β－Ｄ－吡喃木糖甙（Ⅰ），蛇莓甙Ｂ的结构为３＇－Ｏ－甲基－鞣花酸－４－Ｏ－α－Ｌ－呋喃阿拉伯糖甙（Ⅱ）。另外４个化合物为已知三萜类化合物：３β－羟基－乌苏烷－１２－烯－２８－羧酸（Ⅲ），２α，３β，１９α－三羟基－乌苏烷－１２－烯－２８－羧酸（Ⅳ），２α，３β，１９α－三羟基－乌苏烷－１２－烯－２８－羧酸－２８－Ｏ－β－Ｄ－吡喃葡萄糖甙（Ⅴ），２α，３α，１９α－三羟基－乌苏烷－１２－烯－２８－羧酸－２８－Ｏ－β－Ｄ－吡喃葡萄糖甙（Ⅵ）。其中化合物Ⅳ，Ⅴ和Ⅵ为首次从该属植物中分离得到。