28 resultados para PLACEBO-CONTROLLED TRIALS
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The aim of the study was to investigate the effects of acute supplementation of sodium bicarbonate (NaHCO3) on maximal accumulated oxygen deficit (MAOD) determined by a single supramaximal effort (MAODALT) in running and the correlation with 200- and 400-m running performances. Fifteen healthy men (age, 23 ± 4 years; maximal oxygen uptake, 50.6 ± 6.1 mL·kg(-1)·min(-1)) underwent a maximal incremental exercise test and 2 supramaximal efforts at 110% of the intensity associated with maximal oxygen uptake, which was carried out after ingesting either 0.3 g·kg(-1) body weight NaHCO3 or a placebo (dextrose) and completing 200- and 400-m performance tests. The study design was double-blind, crossover, and placebo-controlled. Significant differences were found between the NaHCO3 and placebo conditions for MAODALT (p = 0.01) and the qualitative inference for substantial changes showed a very likely positive effect (98%). The lactic anaerobic contribution in the NaHCO3 ingestion condition was significantly higher (p < 0.01) and showed a very likely positive effect (99% chance), similar to that verified for peak blood lactate concentration (p < 0.01). No difference was found for time until exhaustion (p = 0.19) or alactic anaerobic contribution (p = 0.81). No significant correlations were observed between MAODALT and 200- and 400-m running performance tests. Therefore, we can conclude that both MAODALT and the anaerobic lactic metabolism are modified after acute NaHCO3 ingestion, but it is not correlated with running performance.
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Background Anorexia Nervosa ( AN) is an illness characterised by extreme concern about body weight and shape, severe self-imposed weight loss, and endocrine dysfunction. In spite of its high mortality, morbidity and chronicity, there are few intervention studies on the subject.Objectives The aim of this review was to evaluate the efficacy and acceptability of antidepressant drugs in the treatment of acute AN.Search strategy The strategy comprised of database searches of the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register, MEDLINE (1966 to April 28th, 2005), EMBASE (1980 to week 36, 2004), PsycINFO (1969 to August week 5, 2004), handsearching the International Journal of Eating Disorders and searching the reference lists of all papers selected. Personal letters were sent to researchers in the field requesting information on unpublished or in-progress trials.Selection criteria All randomised controlled trials of antidepressant treatment for AN patients, as de fined by the Diagnostic and Statistical Manual, fourth edition (DSM-IV) or similar international criteria, were selected.Data collection and analysis Quality ratings were made giving consideration to the strong relationship between allocation concealment and potential for bias in the results; studies meeting criteria A and B were included. Trials were excluded if non-completion rates were above 50%. The standardised mean difference and relative risk were used for continuous data and dichotomous data comparisons, respectively. Whenever possible, analyses were performed according to intention- to-treat principles. Heterogeneity was tested with the I-squared statistic. Weight change was the primary outcome. Secondary outcomes were severity of eating disorder, depression and anxiety symptoms, and global clinical state. Acceptability of treatment was evaluated by considering non-completion rates.Main results Only seven studies were included. Major methodological limitations such as small trial size and large confidence intervals decreased the power of the studies to detect differences between treatments, and meta-analysis of data was not possible for the majority of outcomes. Four placebo-controlled trials did not find evidence that antidepressants improved weight gain, eating disorder or associated psychopathology. Isolated findings, favouring amineptine and nortriptyline, emerged from the antidepressant versus antidepressant comparisons, but cannot be conceived as evidence of efficacy of a specific drug or class of antidepressant in light of the findings from the placebo comparisons. Non-completion rates were similar between the compared groups.Authors' conclusions A lack of quality information precludes us from drawing de finite conclusions or recommendations on the use of antidepressants in acute AN. Future studies testing safer and more tolerable antidepressants in larger, well designed trials are needed to provide guidance for clinical practice.
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OBJECTIVE: The participation of humans in clinical cardiology trials remains essential, but little is known regarding participant perceptions of such studies. We examined the factors that motivated participation in such studies, as well as those that led to participant frustration.METHODS: Patients who had participated in hypertension and coronary arterial disease (phases II, III, and IV) clinical trials were invited to answer a questionnaire. They were divided into two groups: Group I, which included participants in placebo-controlled clinical trials after randomization, and Group II, which included participants in clinical trials in which the tested treatment was compared to another drug after randomization and in which a placebo was used in the washout period.RESULTS: Eighty patients (47 patients in Group I and 33 patients in Group II) with different socio-demographic characteristics were interviewed. Approximately 60% of the patients were motivated to participate in the trial with the expectation of personal benefit. Nine participants (11.2%) expressed the desire to withdraw, which was due to their perception of risk during the testing in the clinical trial (Group I) and to the necessity of repeated returns to the institution (Group II). However, the patients did not withdraw due to fear of termination of hospital treatment.CONCLUSIONS: Although this study had a small patient sample, the possibility of receiving a benefit from the new tested treatment was consistently reported as a motivation to participate in the trials.
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Os autores definem mastalgia cíclica pré-menstrual, (MCPM), repassam os principais mecanismos do ciclo celular da mama, e com base nestes conhecimentos propõem a sua classificação em três tipos, segundo a fisiologia do ciclo mamário: tipo 1 - caracterizado pela distensão localizada de ductos e adensamento do tecido conjuntivo em volta de pequenas dilatações. tipo II - caracterizado pelo edema intersticial, e tipo III - caracterizado pela combinação dos dois processos etiopatogênicos. OBJETIVO: Por meio de estudo prospectivo, aleatório, triplo cego e controlado, comparar a ação de placebo com associação de vitaminas A-D-E e doses baixas de ácido acetilsalicílico. MÉTODOS: Foram observadas 259 portadoras de MCPM, acompanhadas durante seis meses para estudo comparativo das drogas empregadas no alívio da dor. Destas, foram selecionadas 81 pacientes por critérios rigorosos, divididas em três grupos de 27, que receberam, respectivamente, aspirina, associação de vitaminas e placebo. A dor foi classificada em grau I (sem dor), grau II (dor moderada) e grau III (dor intensa). Os métodos estatísticos realizados mostraram que o número de pacientes em cada grupo era satisfatório. Foi empregado o teste de Tukey para comparação dos resultados e significância a 5%. RESULTADOS: As características clínicas, idade, peso, altura e IMC, antecedentes obstétricos e duração da amamentação foram semelhantes nos três grupos. Houve redução de intensidade da dor nos três grupos, principalmente naquele que recebeu placebo. CONCLUSÃO: O estudo realizado, segundo metodologia aceitável, porque foi prospectivo, controlado, triplo cego e aleatório, não mostrou diferenças significativas no tratamento da mastalgia cíclica pré-menstrual entre aspirina e associação de vitaminas, mas revelou superioridade do placebo.
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Introduction: Open access publishing is becoming increasingly popular within the biomedical sciences. SciELO, the Scientific Electronic Library Online, is a digital library covering a selected collection of Brazilian scientific journals many of which provide open access to full-text articles. This library includes a number of dental journals some of which may include reports of clinical trials in English, Portuguese and/or Spanish. Thus, SciELO could play an important role as a source of evidence for dental healthcare interventions especially if it yields a sizeable number of high quality reports. Objective: The aim of this study was to identify reports of clinical trials by handsearching of dental journals that are accessible through SciELO, and to assess the overall quality of these reports. Material and methods: Electronic versions of six Brazilian dental Journals indexed in SciELO were handsearched at www.scielo.br in September 2008. Reports of clinical trials were identified and classified as controlled clinical trials (CCTs - prospective, experimental studies comparing 2 or more healthcare interventions in human beings) or randomized controlled trials (RCTs - a random allocation method is clearly reported), according to Cochrane eligibility criteria. Criteria to assess methodological quality included: method of randomization, concealment of treatment allocation, blinded outcome assessment, handling of withdrawals and losses and whether an intention-to-treat analysis had been carried out. Results: The search retrieved 33 CCTs and 43 RCTs. A majority of the reports provided no description of either the method of randomization (75.3%) or concealment of the allocation sequence (84.2%). Participants and outcome assessors were reported as blinded in only 31.2% of the reports. Withdrawals and losses were only clearly described in 6.5% of the reports and none mentioned an intention-to-treat analysis or any similar procedure. Conclusions: The results of this study indicate that a substantial number of reports of trials and systematic reviews are available in the dental journals listed in SciELO, and that these could provide valuable evidence for clinical decision making. However, it is clear that the quality of a number of these reports is of some concern and that improvement in the conduct and reporting of these trials could be achieved if authors adhered to internationally accepted guidelines, e. g. the CONSORT statement.
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OBJECTIVE: To study whether antioxidant supplementation will reduce the incidence of preeclampsia among patients at increased risk.METHODS: A randomized, placebo-controlled, double-blind clinical trial was conducted at four Brazilian sites. Women between 12 0/7 weeks and 19 6/7 weeks of gestation and diagnosed to have chronic hypertension or a prior history of preeclampsia were randomly assigned to daily treatment with both vitamin C (1,000 mg) and vitamin E (400 International Units) or placebo. Analyses were adjusted for clinical site and risk group (prior preeclampsia, chronic hypertension, or both). A sample size of 734 would provide 80% power to detect a 40% reduction in the risk of preeclampsia, assuming a placebo group rate of 21% and alpha=.05. The a level for the final analysis, adjusted for interim looks, was 0.0458.RESULTS: Outcome data for 707 of 739 randomly assigned patients revealed no significant reduction in the rate of preeclampsia (study drug, 13.8% [49 of 355] compared with placebo, 15.6% [55 of 352], adjusted risk ratio 0.87 [95.42% confidence interval 0.61-1.25]). There were no differences in mean gestational age at delivery or rates of perinatal mortality, abruptio placentae, pre-term delivery, and small for gestational age or low birth weight infants. Among patients without chronic hypertension, there was a slightly higher rate of severe preeclampsia in the study group (study drug, 6.5% [11 of 170] compared with placebo, 2.4% [4 of 168], exact P=.11, odds ratio 2.78, 95% confidence interval 0.79-12.62).CONCLUSION: This trial failed to demonstrate a benefit of antioxidant supplementation in reducing the rate of preeclampsia among'patients with chronic hypertension and/or prior preeclampsia.
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The purpose of this review was to assess the efficacy of recombinant LH (r-LH) supplementation for controlled ovarian stimulation in recombinant FSH (r-FSH) and GnRH-agonist (GnRH-a) protocol for IVF/ICSI cycles. Search strategies included on-line surveys of databases from 1990 to 2006. Four trials fulfilled the inclusion criteria (Lisi et al. 2002, Humaidan et al. 2004, Marrs et al. 2004, Tarlatzis et al. 2006). When the review was carried out advantages were observed for the r-LH supplementation protocol with respect to a fewer days of stimulation, a fewer total amount of r-FSH administered and a higher serum estradiol levels on the day of hCG administration. However, these differences were not observed in number of oocyte retrieved, number of mature oocytes, clinical pregnancy per oocyte retrieval, implantation and miscarriage rates. Nevertheless, more randomized controlled trials are necessary before evidence-based recommendations regarding exogenous r-LH supplementation in ovarian stimulation protocols with r-FSH and GnRH-a for assisted reproduction treatment can be provided.
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The purpose of this study was to evaluate anti-inflammatory drugs in the medium- and long-term management of mild to moderate carpal tunnel syndrome (CTS). The authors conducted a systematic review of the literature on the effectiveness of steroidal and nonsteroidal anti-inflammatory drugs for mild and moderate cases of CTS. There were included only randomized, double-blind clinical trials. Six publications referring to five trials were included in the review. No study on nonsteroidal anti-inflammatory drugs met our inclusion criteria. Although neurophysiological studies have not shown great differences resulting from the application of corticosteroids, the symptomatic benefit provided by such drugs is clear. In the short term, local infiltration provides better results than systemic administration of corticosteroids. Over a 1-year period, however, this difference does not persist. Further double-blind randomized trials evaluating therapeutic efficacy for a longer follow-up period are required to provide stronger evidence for both steroidal and nonsteroidal anti-inflammatories. © 2009 by Lippincott Williams & Wilkins.
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Background: Several anti-inflammatory drugs have been used to reduce pain and discomfort after periodontal surgeries. This study evaluates the efficacy of using etoricoxib and dexamethasone for pain prevention after open-flap debridement surgery. Methods: For this prospective, double-masked, crossover, placebo-controlled, randomized clinical trial, open-flap debridement surgeries were performed on 15 patients (eight males and seven females, age range 20 to 56 years: mean age ± SD: 40 ± 9.7 years) who presented with chronic periodontitis after nonsurgical periodontal therapy at three quadrants. Each patient underwent three surgical procedures at intervals of 30 days and received one of the following premedication protocols 1-hour before surgery: group 1 = placebo, group 2 = 8 mg dexamethasone, and group 3 = 120 mg etoricoxib. Rescue medication (750 mg acetaminophen) was given to each patient who was instructed to take it when necessary. Pain intensity and discomfort were evaluated by a 101-point numeric rate scale and a four-point verbal rate scale, respectively, hourly for the first 8 hours after surgery and three times a day on the following 3 days. Results: The results demonstrate that groups 2 and 3 present reduced postoperative pain-intensity levels compared to group 1. There were statistically significant differences at the 4, 5, 6, 7, and 8 hour-periods after surgery (Friedman test; P<0.05). Furthermore, rescue-medication intake was significantly lower for groups 2 and 3 than for group 1 (analysis of variance; P<0.02). Conclusion: The adoption of a preemptive medication protocol using etoricoxib or dexamethasone may be considered effective for pain and discomfort prevention after open-flap debridement surgeries.
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Background: Blood pressure (BP) within pre-hypertensive levels confers higher cardiovascular risk and is an intermediate stage for full hypertension, which develops in an annual rate of 7 out of 100 individuals with 40 to 50 years of age. Non-drug interventions to prevent hypertension have had low effectiveness. In individuals with previous cardiovascular disease or diabetes, the use of BP-lowering agents reduces the incidence of major cardiovascular events. In the absence of higher baseline risk, the use of BP agents reduces the incidence of hypertension. The PREVER-prevention trial aims to investigate the efficacy, safety and feasibility of a population-based intervention to prevent the incidence of hypertension and the development of target-organ damage.Methods: This is a randomized, double-blind, placebo-controlled clinical trial, with participants aged 30 to 70 years, with pre-hypertension. The trial arms will be chlorthalidone 12.5 mg plus amiloride 2.5 mg or identical placebo. The primary outcomes will be the incidence of hypertension, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new sub-clinical atherosclerosis, and sudden death. The study will last 18 months. The sample size was calculated on the basis of an incidence of hypertension of 14% in the control group, a size effect of 40%, power of 85% and P alpha of 5%, resulting in 625 participants per group. The project was approved by the Ethics committee of each participating institution.Discussion: The early use of blood pressure-lowering drugs, particularly diuretics, which act on the main mechanism of blood pressure rising with age, may prevent cardiovascular events and the incidence of hypertension in individuals with hypertension. If this intervention shows to be effective and safe in a population-based perspective, it could be the basis for an innovative public health program to prevent hypertension in Brazil.Trial Registration: Clinical Trials NCT00970931. © 2011 Fuchs et al; licensee BioMed Central Ltd.
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Anderson-Fabry disease is an X-linked defect of glycosphingolipid metabolism. Progressive renal insufficiency is a major source of morbidity, additional complications result from cardio- and cerebro-vascular involvement. Survival is reduced among affected males and symptomatic female carriers. To evaluate the effectiveness and safety of enzyme replacement therapy compared to other interventions, placebo or no interventions, for treating Anderson-Fabry disease. We searched 'Clinical Trials' on The Cochrane Library, MEDLINE, EMBASE, LILACS and the Cystic Fibrosis and Genetic Disorders Group's Inborn Errors of Metabolism Trials Register (date of the most recent search: 11 September 2012). The original search was performed in September 2008.Date of the most recent search of the Cystic Fibrosis and Genetic Disorders Group's Inborn Errors of Metabolism Trials Register: 11 September 2012. Randomized controlled trials of agalsidase alfa or beta in participants diagnosed with Anderson-Fabry disease. Two authors selected relevant trials, assessed methodological quality and extracted data. Six trials comparing either agalsidase alfa or beta in 223 participants fulfilled the selection criteria.Both trials comparing agalsidase alfa to placebo reported on globotriaosylceramide concentration in plasma and tissue; aggregate results were non-significant. One trial reported pain scores, there was a statistically significant improvement for participants receiving treatment at up to three months, mean difference -2.10 (95% confidence interval (CI) -3.79 to -0.41); at up to five months, mean difference -1.90 (95% CI -3.65 to -0.15); and at up to six months, mean difference -2.00 (95% CI -3.66 to -0.34). There was a significant difference in pain-related quality of life at over five months and up to six months, mean difference -2.10 (95% CI -3.92 to -0.28) but not at other time-points. Neither trial reported deaths.One of the three trials comparing agalsidase beta to placebo reported on globotriaosylceramide concentration in plasma and tissue and showed significant improvement: kidney, mean difference -1.70 (95% CI -2.09 to -1.31); heart, mean difference -0.90 (95% CI -1.18 to -0.62); and composite results (renal, cardiac, and cerebrovascular complications and death), mean difference -4.80 (95% CI -5.45 to -4.15). There was no significant difference between groups for death; no trials reported on pain.Only one trial compared agalsidase alfa to agalsidase beta. There was no significant difference between the groups for any adverse events, risk ratio 0.36 (95% CI 0.08 to 1.59), or any serious adverse events; risk ratio 0.30; 95% CI 0.03 to 2.57). Six small, poor quality randomised controlled trials provide no robust evidence for use of either agalsidase alfa and beta to treat Anderson-Fabry disease.
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Pós-graduação em Bases Gerais da Cirurgia - FMB
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)