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131.
132.

Aims

To aid public health policymaking, we studied the cost-effectiveness of buprenorphine, naltrexone, and placebo interventions for heroin dependence in Malaysia.

Design

We estimated the cost-effectiveness ratios of three treatments for heroin dependence. We used a microcosting methodology to determine fixed, variable, and societal costs of each intervention. Cost data were collected from investigators, staff, and project records on the number and type of resources used and unit costs; societal costs for participants’ time were estimated using Malaysia’s minimum wage. Costs were estimated from a provider and societal perspective and reported in 2004 US dollars.

Setting

Muar, Malaysia.

Participants

126 patients enrolled in a randomized, double-blind, placebo-controlled clinical trial in Malaysia (2003–2005) receiving counseling and buprenorphine, naltrexone, or placebo for treatment of heroin dependence.

Measurements

Primary outcome measures included days in treatment, maximum consecutive days of heroin abstinence, days to first heroin use, and days to heroin relapse. Secondary outcome measures included treatment retention, injection drug use, illicit opiate use, AIDS Risk Inventory total score, and drug risk and sex risk subscores.

Findings

Buprenorphine was more effective and more costly than naltrexone for all primary and most secondary outcomes. Incremental cost-effectiveness ratios were below $50 for primary outcomes, mostly below $350 for secondary outcomes. Naltrexone was dominated by placebo for all secondary outcomes at almost all endpoints. Incremental treatment costs were driven mainly by medication costs, especially the price of buprenorphine.

Conclusions

Buprenorphine appears to be a cost-effective alternative to naltrexone that might enhance economic productivity and reduce drug use over a longer term.  相似文献   
133.
Recently, selected reaction monitoring mass spectrometry (SRM-MS) has been more frequently applied to measure low abundance biomarker candidates in tissues and biofluids, owing to its high sensitivity and specificity, simplicity of assay configuration, and exceptional multiplexing capability. In this study, we report for the first time the development of immunoaffinity depletion-based workflows and SRM-MS assays that enable sensitive and accurate quantification of total and free prostate-specific antigen (PSA) in serum without the requirement for specific PSA antibodies. Low ng/mL level detection of both total and free PSA was consistently achieved in both PSA-spiked female serum samples and actual patient serum samples. Moreover, comparison of the results obtained when SRM PSA assays and conventional immunoassays were applied to the same samples showed good correlation in several independent clinical serum sample sets. These results demonstrate that the workflows and SRM assays developed here provide an attractive alternative for reliably measuring candidate biomarkers in human blood, without the need to develop affinity reagents. Furthermore, the simultaneous measurement of multiple biomarkers, including the free and bound forms of PSA, can be performed in a single multiplexed analysis using high-resolution liquid chromatographic separation coupled with SRM-MS. This article is part of a Special Issue entitled: Translational Proteomics.  相似文献   
134.
Aggresomes are cytoplasmic inclusions which are localized at the microtubule organizing center (MTOC) as a result of induced proteasome inhibition, stress or over-expression of certain proteins. Aggresomes are linked to the pathogenesis of many neurodegenerative diseases. Here we studied whether amyloid precursor protein (APP), a type-I transmembrane glycoprotein, is localized in aggresomes after exposure to stress condition. Using confocal microscopy we found that APP is located in aggresomes and co-localized with vimentin, γ-tubulin, 20S and ubiquitin at the MTOC in response to proteasome dysfunction. An interaction between vimentin and APP was found after proteasome inhibition suggesting that APP is an additional protein constituent of aggresomes. Suppression of the proteasome system in APP-HEK293 cells overexpressing APP or transfected with APP Swedish mutation caused an accumulation of stable, detergent-insoluble forms of APP containing poly-ubiquitinated proteins. In addition, brain homogenates from transgenic mice expressing human APP with the Arctic mutation demonstrated an interaction between APP and the aggresomal-marker vimentin. These data suggest that malfunctioning of the proteasome system caused by mutation or overexpression of pathological or non-pathological proteins may lead to the accumulation of stable aggresomes, perhaps contributing to the neurodegeneration.  相似文献   
135.
The experimental study identified the antiviral activity of Bacillus pumilus RNase (binase) against the reovirus of serotype 1/strain Lang. For the first time, it has been found that 50 μg/mL of binase effectively reduced the hemagglutinin and cytocidal activity of reovirus in Vero cell line. The preincubation of the enzyme with reovirus before infection of the cells inhibited the viral replication. To determine the stagedependent effect of reovirus reproduction upon binase inhibition, the infected cells were treated with binase or RNase A at different phases of the infectious cycle. The treatment of virus-infected cells has revealed that both enzymes have a maximal antiviral effect on the reovirus propagation during early phases of the reovirus reproduction cycle, with binase being more effective than RNase A. It has been hypothesized that the combined action of the oncolytic reovirus and binase is promising for the elimination of tumor cells carrying mutated RAS gene.  相似文献   
136.
Soil and water contaminated with arsenic (As) pose a major environmental and human health problem in Bangladesh. Phytoremediation, a plant-based technology, may provide an economically viable solution for remediating the As-polluted sites. The use of indigenous plants with a high tolerance and accumulation capacity for As may be a very convenient approach for phytoremediation. To assess the potential of native plant species for phytoremediation, plant and soil samples were collected from four As-contaminated (groundwater) districts in Bangladesh. The main criteria used for selecting plants for phytoremediation were high bioconcentration factors (BCFs) and translocation factors (TFs) of As. From the results of a screening of 49 plant species belonging to 29 families, only one species of fern (Dryopteris filix-mas), three herbs (Blumea lacera, Mikania cordata, and Ageratum conyzoides), and two shrubs (Clerodendrum trichotomum and Ricinus communis) were found to be suitable for phytoremediation. Arsenic bioconcentration and translocation factors > 1 suggest that these plants are As-tolerant accumulators with potential use in phytoextraction. Three floating plants (Eichhornia crassipes, Spirodela polyrhiza, and Azolla pinnata) and a common wetland weed (Monochoria vaginalis) also showed high BCF and TF values; therefore, these plants may be promising candidates for cleaningup As-contaminated surface water and wetland areas. The BCF of Oryza sativa, obtained from As-contaminated districts was > 1, which highlights possible food-chain transfer issues for As-contaminated areas in Bangladesh.  相似文献   
137.
BACKGROUND: Nitric oxide (NO) production is increased in inflammatory bowel disease (IBD), and measurement of NO metabolites may be useful for monitoring disease activity. AIMS AND OBJECTIVES: To characterise urinary nitrite levels, a stable metabolite of NO, in IBD and to evaluate its potential as a marker of disease activity. METHODS: Twelve-hour urinary nitrites were measured by the microplate assay method in 46 patients with IBD (active; n = 32). Urinary samples from 16 healthy individuals served as controls. RESULTS: Increased levels of urinary nitrites were found in patients with active IBD compared with those with inactive IBD. Twenty-eight out of 32 patients (87.5%) with active IBD had detectable levels of nitrite in their urine as compared with 2/14 (14.3%) patients with inactive IBD. None of the 16 healthy controls had detectable urinary nitrite. Twelve-hour urinary nitrite in active compared with inactive IBD: 5 0.7 versus 0.1+/-0.04 micromol (P < 0.05). There was good correlation between urinary nitrite and some markers of disease activity in IBD such as C-reactive protein and microalbuminuria but not with erythrocyte sedimentation rate. Conclusions: Increased levels of nitrite were detected in urine of patients with active IBD, consistent with increased NO synthesis. This simple assay may be exploited as a potential marker of disease activity in IBD.  相似文献   
138.
The putative biosynthetic gene cluster for the alpha-glucosidase inhibitor acarbose was identified in the producer Actinoplanes sp. 50/110 by cloning a DNA segment containing the conserved gene for dTDP-D-glucose 4,6-dehydratase, acbB. The two flanking genes were acbA (dTDP-D-glucose synthase) and acbC, encoding a protein with significant similarity to 3-dehydroquinate synthases (AroB proteins). The acbC gene was overexpressed heterologously in Streptomyces lividans 66, and the product was shown to be a C7-cyclitol synthase using sedo-heptulose 7-phosphate, but not ido-heptulose 7-phosphate, as its substrate. The cyclization product, 2-epi-5-epi-valiolone ((2S,3S,4S,5R)-5-(hydroxymethyl)cyclohexanon-2,3,4,5-tetrol), is a precursor of the valienamine moiety of acarbose. A possible five-step reaction mechanism is proposed for the cyclization reaction catalyzed by AcbC based on the recent analysis of the three-dimensional structure of a eukaryotic 3-dehydroquinate synthase domain (Carpenter, E. P., Hawkins, A. R., Frost, J. W., and Brown, K. A. (1998) Nature 394, 299-302).  相似文献   
139.
Germline mutations affecting a single allele of BRCA2 increase susceptibility to breast and ovarian cancer, whilst germline inheritance of certain bi-allelic mutations causes a Fanconi anaemia-like syndrome. Here, we review current knowledge of the BRCA2 protein, focussing on recent studies that provide mechanistic insight into its biological function in regulating DNA recombination reactions mediated by the RAD51 recombinase. We argue that the chromosomal instability and cancer predisposition provoked by BRCA2 inactivation are a consequence of the failure to re-start stalled DNA replication, and to repair DNA double-strand breaks, through error-free pathways that depend on homologous pairing between DNA strands.  相似文献   
140.
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