845 resultados para PLACEBO-CONTROLLED CROSSOVER
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STUDY DESIGN: Randomized crossover double-blinded placebo-controlled trial. OBJECTIVE: To investigate if low-level laser therapy (LLLT) can affect biceps muscle performance, fatigue development, and biochemical markers of postexercise recovery. BACKGROUND: Cell and animal studies have suggested that LLLT can reduce oxidative stress and inflammatory responses in muscle tissue. But it remains uncertain whether these findings can translate into humans in sport and exercise situations. METHODS: Nine healthy male volleyball players participated in the study. They received either active LLLT (cluster probe with 5 laser diodes; A = 810 nm; 200 mW power output; 30 seconds of irradiation, applied in 2 locations over the biceps of the nondominant arm; 60 J of total energy) or placebo LLLT using an identical cluster probe. The intervention or placebo were applied 3 minutes before the performance of exercise. All subjects performed voluntary elbow flexion repetitions with a workload of 75% of their maximal voluntary contraction force until exhaustion. RESULTS: Active LLLT increased the number of repetitions by 14.5% (mean +/- SD, 39.6 +/- 4.3 versus 34.6 +/- 5.6; P = .037) and the elapsed time before exhaustion by 8.0% (P = .034), when compared to the placebo treatment. The biochemical markers also indicated that recovery may be positively affected by LLLT, as indicated by postexercise blood lactate levels (P<.01), creatine kinase activity (P = .017), and C-reactive protein levels (P = .047), showing a faster recovery with LLLT application prior to the exercise. CONCLUSION: We conclude that pre-exercise irradiation of the biceps with an LLLT dose of 6 J per application location, applied in 2 locations, increased endurance for repeated elbow flexion against resistance and decreased postexercise levels of blood lactate, creatine kinase, and C-reactive protein. LEVEL OF EVIDENCE: Performance enhancement, level 1b. J Orthop Sports Phys Ther 2010;40(8):524-532. doi:10.2519/jospt.2010.3294
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This study aimed to investigate the effect of 830 nm low-level laser therapy (LLLT) on skeletal muscle fatigue. Ten healthy male professional volleyball players entered a crossover randomized double-blinded placebo-controlled trial. Active LLLT (830 nm wavelength, 100 mW output, spot size 0.0028 cm(2), 200 s total irradiation time) or an identical placebo LLLT was delivered to four points on the biceps humeri muscle immediately before exercises. All subjects performed voluntary biceps humeri contractions with a load of 75% of the maximum voluntary contraction (MVC) force until exhaustion. After active LLLT the mean number of repetitions was significantly higher than after placebo irradiation [mean difference 4.5, standard deviation (SD) +/- 6.0, P = 0.042], the blood lactate levels increased after exercises, but there was no significant difference between the treatments. We concluded that 830 nm LLLT can delay the onset of skeletal muscle fatigue in high-intensity exercises, in spite of increased blood lactate levels.
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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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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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Pós-graduação em Cirurgia Veterinária - FCAV
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Methods We conducted a phase I, multicenter, randomized, double-blind, placebo-controlled, multi-arm (10) parallel study involving healthy adults to evaluate the safety and immunogenicity of influenza A (H1N1) 2009 non-adjuvanted and adjuvanted candidate vaccines. Subjects received two intramuscular injections of one of the candidate vaccines administered 21 days apart. Antibody responses were measured by means of hemagglutination-inhibition assay before and 21 days after each vaccination. The three co-primary immunogenicity end points were the proportion of seroprotection >70%, seroconversion >40%, and the factor increase in the geometric mean titer >2.5. Results A total of 266 participants were enrolled into the study. No deaths or serious adverse events were reported. The most commonly solicited local and systemic adverse events were injection-site pain and headache, respectively. Only three subjects (1.1%) reported severe injection-site pain. Four 2009 influenza A (H1N1) inactivated monovalent candidate vaccines that met the three requirements to evaluate influenza protection, after a single dose, were identified: 15 μg of hemagglutinin antigen without adjuvant; 7.5 μg of hemagglutinin antigen with aluminum hydroxide, MPL and squalene; 3.75 μg of hemagglutinin antigen with aluminum hydroxide and MPL; and 3.75 μg of hemagglutinin antigen with aluminum hydroxide and squalene. Conclusions Adjuvant systems can be safely used in influenza vaccines, including the adjuvant monophosphoryl lipid A (MPL) derived from Bordetella pertussis with squalene and aluminum hydroxide, MPL with aluminum hydroxide, and squalene and aluminum hydroxide.
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Objetivo: O objetivo deste estudo foi comparar o efeito do tratamento hormonal do hormônio Gonadotrofina Coriônica Humana (HCG), em dois esquemas posológicos diferentes, ao placebo quanto sua efetividade e segurança no tratamento da Criptorquidia. Métodos: Este estudo é um ensaio clínico randomizado, duplo-cego, placebo-controlado de 14 semanas. A amostra de 92 pacientes que foram randomizados para o grupo-HCG dias alternados, denominados de Grupo G1 (N = 29), para o grupo HCG a cada quatro dias, denominados Grupo G4 (N= 33) e o grupo-placebo, denominados como Grupo O(N = 30). 2. Os desfechos clínicos primários para este estudo foram 1) Cura, 2) Melhora, 3) Não Cura. Os desfechos complementares foram: 4) Efeitos adversos, 5) Níveis séricos hormonais. Resultados: Não existiram diferenças entre os grupos HCG dias alternados, HCG a cada quatro dias e placebo para as medidas dos desfechos primários. 1) Cura: G1: 3/29(3,3%), G4: 4/33(4,3%) e O: 3/30(3,3%) 2) Melhora: G1:3/29(3,3%), G4: 1/33(1,1%) e O: 3/30(3,3%). 3) Não Cura: G1: 23/29(25%), G4: 28/33(30,4%) e O: 24/30(26,1%) p=0,815. 4) Os efeitos adversos mais freqüentes em nossa amostra foram: Aumento do numero de ereções: não foi possível avaliar. 5) Níveis séricos hormonais: Testosterona sérica: G1: de 34,15 ± 5,8ng/ml; G4: 49,6± 5,6 ng/ml e O: 7,5± 3,5ng/ml. Hormônio Luteinizante (LH): G1: 0,22± 0,2 , G4: 0,07±0,1 e O: 0,08±0,02 Hormônio Folículo Estimulante (FSH): G1: 0,88±0,16, G4: 0,3±0,1 e O 1,15±0,6. Conclusão: Não foi encontrada nenhuma diferença estatística no tratamento com HCG, independente da posologia adotada, e placebo. Os autores concluem a hormonioterapia com HCG não demonstrou superioridade na eficácia e ou segurança no tratamento da criptorquidia ao placebo.
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The goal of this randomized, open, controlled crossover manikin study was to compare the performance of "Animax", a manually operated hand-powered mechanical resuscitation device (MRD) to standard single rescuer basic life support (BLS).
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Although extensive indirect evidence exists to suggest that the central dopaminergic system plays a significant role in the modulation of arousal, the functional effect of the dopaminergic influence on the regulation of the sleep-wake cycle remains unclear. Thirteen healthy volunteers and 15 unmedicated subjects with a history of major depressive disorder underwent catecholamine depletion (CD) using oral alpha-methyl-para-tyrosine in a randomized, placebo-controlled, double-blind, crossover study. The main outcome measures in both sessions were sleepiness (Stanford-Sleepiness-Scale), cerebral glucose metabolism (positron emission tomography), and serum prolactin concentration. CD consistently induced clinically relevant sleepiness in both groups. The CD-induced prolactin increase significantly correlated with CD-induced sleepiness but not with CD-induced mood and anxiety symptoms. CD-induced sleepiness correlated with CD-induced increases in metabolism in the medial and orbital frontal cortex, bilateral superior temporal cortex, left insula, cingulate motor area and in the vicinity of the periaqueductal gray. This study suggests that the association between dopamine depletion and sleepiness is independent of the brain reward system and the risk for depression. The visceromotor system, the cingulate motor area, the periaqueductal gray and the caudal hypothalamus may mediate the impact of the dopaminergic system on regulation of wakefulness and sleep.
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The orexin system is a key regulator of sleep and wakefulness. In a multicenter, double-blind, randomized, placebo-controlled, two-way crossover study, 161 primary insomnia patients received either the dual orexin receptor antagonist almorexant, at 400, 200, 100, or 50 mg in consecutive stages, or placebo on treatment nights at 1-week intervals. The primary end point was sleep efficiency (SE) measured by polysomnography; secondary end points were objective latency to persistent sleep (LPS), wake after sleep onset (WASO), safety, and tolerability. Dose-dependent almorexant effects were observed on SE , LPS , and WASO . SE improved significantly after almorexant 400 mg vs. placebo (mean treatment effect 14.4%; P < 0.001). LPS (–18 min (P = 0.02)) and WASO (–54 min (P < 0.001)) decreased significantly at 400 mg vs. placebo. Adverse-event incidence was dose-related. Almorexant consistently and dose-dependently improved sleep variables. The orexin system may offer a new treatment approach for primary insomnia.
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BACKGROUND Classically, clinical trials are based on the placebo-control design. Our aim was to analyze the placebo effect in Huntington's disease. METHODS Placebo data were obtained from an international, longitudinal, placebo-controlled trial for Huntington's disease (European Huntington's Disease Initiative Study Group). One-hundred and eighty patients were evaluated using the Unified Huntington Disease Rating Scale over 36 months. A placebo effect was defined as an improvement of at least 50% over baseline scores in the Unified Huntington Disease Rating Scale, and clinically relevant when at least 10% of the population met it. RESULTS Only behavior showed a significant placebo effect, and the proportion of the patients with placebo effect ranged from 16% (first visit) to 41% (last visit). Nondepressed patients with better functional status were most likely to be placebo-responders over time. CONCLUSIONS In Huntington's disease, behavior seems to be more vulnerable to placebo than overall motor function, cognition, and function
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OBJECTIVE: To determine the impact of a community based Helicobacter pylori screening and eradication programme on the incidence of dyspepsia, resource use, and quality of life, including a cost consequences analysis. DESIGN: H pylori screening programme followed by randomised placebo controlled trial of eradication. SETTING: Seven general practices in southwest England. PARTICIPANTS: 10,537 unselected people aged 20-59 years were screened for H pylori infection (13C urea breath test); 1558 of the 1636 participants who tested positive were randomised to H pylori eradication treatment or placebo, and 1539 (99%) were followed up for two years. INTERVENTION: Ranitidine bismuth citrate 400 mg and clarithromycin 500 mg twice daily for two weeks or placebo. MAIN OUTCOME MEASURES: Primary care consultation rates for dyspepsia (defined as epigastric pain) two years after randomisation, with secondary outcomes of dyspepsia symptoms, resource use, NHS costs, and quality of life. RESULTS: In the eradication group, 35% fewer participants consulted for dyspepsia over two years compared with the placebo group (55/787 v 78/771; odds ratio 0.65, 95% confidence interval 0.46 to 0.94; P = 0.021; number needed to treat 30) and 29% fewer participants had regular symptoms (odds ratio 0.71, 0.56 to 0.90; P = 0.05). NHS costs were 84.70 pounds sterling (74.90 pounds sterling to 93.91 pounds sterling) greater per participant in the eradication group over two years, of which 83.40 pounds sterling (146 dollars; 121 euro) was the cost of eradication treatment. No difference in quality of life existed between the two groups. CONCLUSIONS: Community screening and eradication of H pylori is feasible in the general population and led to significant reductions in the number of people who consulted for dyspepsia and had symptoms two years after treatment. These benefits have to be balanced against the costs of eradication treatment, so a targeted eradication strategy in dyspeptic patients may be preferable.
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BACKGROUND: In Switzerland approximately 8% of infants are born prematurely. Some of them undergo mechanical ventilation including endotracheal suctioning (ETS). ETS is one of the most frequently performed interventions and is linked to stress and pain, but its treatment is controversial. In Switzerland there is a lack of standardisation in pain relief for ETS. AIMS: To test the hypothesis that an intermittent dose of morphine reduces pain during ETS and that subsequent multisensorial stimulation (MSS), as a non pharmacological comforting intervention, helps infants to recover from experienced pain. METHOD: A randomized placebo controlled trial in two tertiary neonatal intensive care units (NICU) with a sample of 30 mechanically ventilated preterm infants was conducted. Pain was measured by three pain assessment tools (Bernese Pain Scale for Neonates, Premature Infant Pain Profile and Visual Analogue Scale) RESULTS: Morphine did not lead to any pain relief from ETS as measured by three pain scales. Nor did the comforting intervention of MSS show any effect. Repeated-measure analysis of variance for the within and between groups comparison showed no statistical significance. CONCLUSIONS: The administration of morphine for pain relief in ventilated preterm neonates during ETS remains questionable and the use of MSS as a comforting intervention after painful stimulus cannot be recommended. The validity testing of the instruments for this patient population should undergo a systematic validation trajectory. Future research should focus on options among non pharmacological interventions for relieving pain during ETS.
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BACKGROUND: The efficacy of granulocyte colony-stimulating factor (G-CSF) for coronary collateral growth promotion and thus impending myocardial salvage has not been studied so far, to our best knowledge. METHODS AND RESULTS: In 52 patients with chronic stable coronary artery disease, age 62+/-11 years, the effect on a marker of myocardial infarct size (ECG ST segment elevation) and on quantitative collateral function during a 1-minute coronary balloon occlusion was tested in a randomized, placebo-controlled, double-blind fashion. The study protocol before coronary intervention consisted of occlusive surface and intracoronary lead ECG recording as well as collateral flow index (CFI, no unit) measurement in a stenotic and a > or =1 normal coronary artery before and after a 2-week period with subcutaneous G-CSF (10 microg/kg; n=26) or placebo (n=26). The CFI was determined by simultaneous measurement of mean aortic, distal coronary occlusive, and central venous pressure. The ECG ST segment elevation >0.1 mV disappeared significantly more often in response to G-CSF (11/53 vessels; 21%) than to placebo (0/55 vessels; P=0.0005), and simultaneously, CFI changed from 0.121+/-0.087 at baseline to 0.166+/-0.086 at follow-up in the G-CSF group, and from 0.152+/-0.082 to 0.131+/-0.071 in the placebo group (P<0.0001 for interaction of treatment and time). The absolute change in CFI from baseline to follow-up amounted to +0.049+/-0.062 in the G-CSF group and to -0.010+/-0.060 in the placebo group (P<0.0001). CONCLUSIONS: Subcutaneous G-CSF is efficacious during a short-term protocol in improving signs of myocardial salvage by coronary collateral growth promotion.