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Coffee and gastric cancer: systematic review and meta-analysis.

We systematically reviewed the literature on the association between coffee consumption and gastric cancer and performed a meta-analysis of the results. Published cohort and case-control studies were identified in PubMed and reference lists. Random effects meta-analysis was used to pool effects from 23 studies, and heterogeneity was explored by stratification and meta-regression. The odds ratio (OR) for the overall association between coffee and gastric cancer (highest vs. lowest category of exposure) was 0.97 (95%CI: 0.86-1.09), similar for cohort (OR = 1.02; 95%CI: 0.76-1.37) and case-control studies (population-based: OR = 0.90; 95%CI: 0.70-1.15; hospital-based: OR = 0.97; 95%CI: 0.83-1.13). The OR was 1.26 (95%CI: 1.02-1.57) when considering five studies conducted in the USA, 0.97 (95%CI: 0.82-1.14) for the five Japanese studies, 0.98 (95%CI: 0.81-1.17) for the six studies from Europe, and 0.64 (95%CI: 0.47-0.86) for the two studies from South America. In this meta-analysis we found no adverse effect of coffee associated with gastric cancer. Knowledge on the level of exposure to different coffee constituents may provide a deeper understanding of this reassuring result and the real role of coffee on cancer risk.

Coffee↗

The treatment of tardive dyskinesia--a systematic review and meta-analysis.

This systematic review aimed to collate randomized controlled trials (RCTs) of various interventions used to treat tardive dyskinesia (TD) and, where appropriate, to combine the data for meta-analysis. Clinical trials were identified by electronic searches, handsearches and contact with principal investigators. Data were extracted independently by two reviewers, for outcomes related to improvement, deterioration, side-effects and drop out rates. Data were pooled using the Mantel-Haenzel Odds Ratio (fixed effect model). For treatments that had significant effects, the number needed to treat (NNT) was calculated. From 296 controlled clinical trials, data were extracted from 47 trials. For most interventions, we could identify no RCT-derived evidence of efficacy. A meta-analysis showed that baclofen, deanol and diazepam were no more effective than a placebo. Single RCTs demonstrated a lack of evidence of any effect for bromocriptine, ceruletide, clonidine, estrogen, gamma linolenic acid, hydergine, lecithin, lithium, progabide, seligiline and tetrahydroisoxazolopyridinol. The meta-analysis found that five interventions were effective: L-dopa, oxypertine, sodium valproate, tiapride and vitamin E; neuroleptic reduction was marginally significant. Data from single RCTs revealed that insulin, alpha methyl dopa and reserpine were more effective than a placebo. There was a significantly increased risk of adverse events associated with baclofen, deanol, L-dopa, oxypertine and reserpine. Meta-analysis of the impact of placebo (n=485) showed that 37.3% of participants showed an improvement. Interpretation of this systematic review requires caution as the individual trials identified tended to have small sample sizes. For many compounds, data from only one trial were available, and where meta-analyses were possible, these were based on a small number of trials. Despite these concerns, the review facilitated the interpretation of the large and diverse range of treatments used for TD. Clinical recommendations for the treatment of TD are made, based on the availability of RCT-derived evidence, the strength of that evidence and the presence of adverse effects.

Double-Blind Method↗

HIV prevention research for men who have sex with men: a systematic review and meta-analysis.

A systematic review of HIV prevention reports published or distributed in the United States as of June 1998 yielded 9 rigorous controlled trials reporting intervention effects on unprotected sex for men who have sex with men. A summary measure of these effects was favorable (odds ratio,.69), statistically significant (95% confidence interval, 0.56-0.86), and very homogeneous. This summary value indicates a 26% reduction in the proportion of men engaging in unprotected anal intercourse. The most clearly favorable effects were observed among interventions that promoted interpersonal skills, were delivered in community-level formats, or focused on younger populations or those at higher behavioral risk. These studies demonstrate that interventions can promote risk reduction among men who have sex with men. Yet given the epidemiology of HIV in the United States, the small number of rigorous controlled intervention trials for this population is striking. Many more rigorous evaluations of HIV prevention efforts with men who have sex with men are needed to ascertain with confidence the effects of specific intervention components, population characteristics, and methodologic features.

Acquired Immunodeficiency Syndrome↗

Measurement of brain metabolites by 1H magnetic resonance spectroscopy in patients with schizophrenia: a systematic review and meta-analysis.

A systematic review of the literature identified 64 published English-language papers that used proton (1H) magnetic resonance spectroscopy to measure N-acetylaspartate (NAA) concurrently in healthy controls and in patients with a diagnosis of schizophrenia (SZ). A total of 1209 controls and 1256 patients have been evaluated, with 88% of studies carried out at 1.5 T field strength, and 77% of studies focused on patients with chronic SZ. There is consistent evidence that NAA is reduced in a broad range of tissues in the SZ brain. Broad consensus (> or =10 studies) is emerging that NAA levels are reduced > or =5% in hippocampus and in both cortical gray matter (GM) and white matter (WM) of the frontal lobe. There is no evidence to support a hypothesis that relative NAA levels are reduced to a different degree in frontal lobe GM and WM, nor is there robust evidence of a difference in NAA levels between patients with first-episode and chronic SZ. Study reliability may be a problem, as most studies appear to be underpowered. With simple assumptions about the inherent difference in NAA levels between patients and controls, it can be calculated that a minimum sample size of approximately 39 patients and 39 controls is required for acceptable statistical power. Only three of 64 studies included enough subjects to have 80% power to detect a 10% NAA reduction in patients, and no studies were adequately powered to detect a 5% NAA reduction with 80% power.

Aspartic Acid↗

Anti-vertebral fracture efficacy of raloxifene: a meta-analysis.

In the Multiple Outcomes of Raloxifene Evaluation (MORE) trial, raloxifene reduced the risk of vertebral fracture. However, a systematic analysis of the anti-vertebral fracture efficacy of raloxifene, which includes the results of newly reported studies, has not been performed. A meta-analysis was carried out using all randomized, double-blind, placebo-controlled trials to determine whether the reduction in the risk for vertebral fracture, reported with raloxifene, was consistent among studies, and to define more accurately the point estimate of the odds ratio. Three prevention studies, two arms of the MORE trial, and three additional treatment studies in which fracture data were available from prospectively scheduled spinal radiographs were included in the analysis. A systematic review of the literature (MedLine, EMBASE) confirmed that no studies with raloxifene had been excluded from this analysis. The effects of raloxifene 60 mg/day (RLX60) and 120 mg/day pooled with 150 mg/day (RLX120/150) were analyzed by intention to treat. There was no significant heterogeneity among the studies included in the meta-analysis. Odds ratio estimates (95% CI) were 0.60 (0.49, 0.74) for RLX60 and 0.51 (0.41, 0.64) for RLX120/150. From these data we infer that raloxifene consistently reduces the risk of vertebral fracture in postmenopausal women.

Bone Density Conservation Agents↗

Dynamically coated capillaries improve the identification power of capillary zone electrophoresis for basic drugs in toxicological analysis.

In systematic toxicological analysis (STA), analytical methods should have a high identification power. This can be suitably expressed by parameters such as mean list length (MLL) or discriminating power (DP). The reproducibility of a method has a great impact on its identification power, and should be as high as possible. In this study, two separation methods based on capillary zone electrophoresis (CZE) were evaluated towards STA applications. Besides a normal phosphate buffer, the commercially available buffer CElixir was used, which is a double-layer dynamic coating system. The coating stabilizes the endoosmotic flow, is independent of the pH, and is claimed to be more reproducible and faster at low pH than with normal buffers. A test set of 73 basic pharmaceutical compounds was analyzed by the two CZE methods. The total analysis time, including rinsing steps, was 8 min when the coating was used and 18 min without the coating. Effective mobilities were calculated and the reproducibilities were a factor of 2 better when the coating was used (between-days SD 0.020 and 0.040 m2/V s with and without the coating, respectively). MLL and DP were calculated for the two CZE methods and for combinations with standardized liquid and gas chromatography systems. CZE with CElixir coating clearly has a high potential for STA applications, as it was shown to have a higher identification power and shorter analysis times than normal CZE.

Electrophoresis, Capillary↗

Meta-analysis finds use of inhaled corticosteroids during pregnancy safe: a systematic meta-analysis review.

Inhaled corticosteroids (ICs) are the drug of choice for asthmatic women during pregnancy, but the results on the effects of these medications on obstetrical and perinatal outcomes are not conclusive. Meta-analysis is the statistical analysis of a collection of analysis results from individual studies for the purpose of integrating the findings. Meta-analysis techniques are necessary because only summary statistics are available in the literature. In order to determine the risk of exposure to ICs, we pooled data from all clinical studies that evaluated the pregnancy and perinatal outcomes in women exposed to this group of drugs during pregnancy by the meta-analytic technique. PUBMED, OVID, EMBASE and SCOPUS databases were searched for studies that investigated birth outcome following exposure to ICs during pregnancy. Data were collected from 1997 to 2005 (up to 31 December). Types of outcome investigated were major malformations, preterm delivery, low birth weight and pregnancy-induced hypertension. The criteria for inclusion of studies in this meta-analysis were exposure of women to any therapeutic dosage of any ICs (fluticasone, beclomethasone, budesonide, triamcinolone and flunisolide) during pregnancy. The results showed that ICs do not increase the risk of major malformations, preterm delivery, low birth weight and pregnancy-induced hypertension. In conclusion, ICs do not increase the rates of any obstetrical outcomes investigated in the present study and interestingly improve the symptoms and are helpful in the management of asthma and thus can be used comfortably during pregnancy.

Abnormalities, Drug-Induced↗

Methodologies analysing individual practice in health care: a systematic review.

AIM OF THE REVIEW: The aim of the systematic review was to identify, explore and evaluate the current level of knowledge of methodologies used in comparative analyses of the individual practice of doctors, nurses and midwives. RATIONALE: The question of how roles and responsibilities might be shared differently between professional groups in order to promote improved, cost-effective health care requires a systematic analysis of existing roles and practice. To do this effectively, knowledge of the methodologies available for such an analysis is essential. METHODS: A systematic review of the literature published since 1989 comparing the practice of doctors, nurses and midwives was undertaken. FINDINGS: The findings are presented in tabular format and include the following categories of published methodologies: experimental/quasi-experimental; descriptive/nonexperimental and qualitative studies. The discussion centres on a critique of quantitative methodologies used to analyse individual practice in relation to role substitution and diversification. The potential contribution of qualitative methodologies in the analysis of individual practice is discussed. CONCLUSIONS: The authors conclude that the current level of knowledge is biased towards quantitative research. It is argued that the assessment of health care roles and responsibilities would be well served by a more balanced approach that recognizes the strengths of both quantitative and qualitative work.

Humans↗

Hydration of DNA bases: analysis of crystallographic data.

We present a systematic analysis of water structure around nucleic acid bases. We have examined 28 crystal structures of oligonucleotides, and have studied the patterns of water around the four bases, guanine, cytosine, adenine, and thymine. The geometries of water positions were calculated up to 4.00 A from base atoms. We have found conformation-dependent differences in both the geometry and extent of hydration of the bases.

Adenine↗