935 resultados para Double-blind Crossover
Resumo:
We explored the washout period of creatine (Cr) after repeated ingestions of high doses of exogenous Cr. Ten athletes ingested daily, in a randomized double-blind study design, 30 g of exoge- nous Cr (n = 5, Cr-group) or a placebo (n = 5, Pl-group). Serum and urine samples were collected 1) before supplementation (BEFO- RE), 2) after one week Cr supplementation (AFTER), and 3) one week later without supplementation (LATER). The Cr and crea- tinine (Crn) concentrations in serum (sCr, sCrn) and in multiple spots urine (uCr, uCrn) were measured. We observed a significant rise (p < 0.01) in sCr, uCr and sCrn between BEFORE and AFTER supplementation in Cr-group, as well as a significant difference between Cr-group and Pl-group. Body weight increased signifi- cantly (+1.5 kg), but relative body fat (%fat) was unchanged. After the washout period in LATER Cr-group, sCr and uCr decreased to low residual values. No loss of body weight occurred during thisperiod. In contrast, sCrn and uCrn returned to baseline values. In conclusion, regular uptake of high doses of exogenous Cr affects both Cr and Crn concentrations in serum (sCr: 14 folds; sCrn: 1.2 folds) and urine (uCr: 140 folds; uCrn: 1.5 folds). An abuse of Cr is therefore mostly spilled over in urine. Surprise drug tests, such as doping controls, happening during the period of Cr supplementa- tion can reveal an important increase in Cr and Crn concentrations, although subjects stopped suddenly Cr loading. The discernible effect of Cr supplementation on these values disappeared within one week.
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There is anecdotal evidence that athletes use the banned substance Synacthen because of its perceived benefit with its associated rise in cortisol. To test the performance-enhancing effects of Synacthen, eight trained cyclists completed two, 2-day exercise sessions separated by 7-10 days. On the first day of each 2-day exercise session, subjects received either Synacthen (0.25 mg, TX) or placebo (PLA) injection. Performance was assessed by a 20-km time trial (TT) after a 90-min fatigue period on day 1 and without the fatiguing protocol on day 2. Plasma androgens and ACTH concentrations were measured during the exercise bouts as well as the rate of perceived exertion (RPE). Spot urines were analyzed for androgens and glucocorticoids quantification. Basal plasma hormones did not differ significantly between PLA and TX groups before and 24 h after the IM injection (P > 0.05). After TX injection, ACTH peaked at 30 min and hormone profiles were significantly different compared to the PLA trial (P < 0.001). RPE increased significantly in both groups as the exercise sessions progressed (P < 0.001) but was not influenced by treatment. The time to completion of the TT was not affected on both days by Synacthen treatment. In the present study, a single IM injection of synthetic ACTH did not improve either acute or subsequent cycling performance and did not influence perceived exertion. The investigated urinary hormones did not vary after treatment, reinforcing the difficulty for ACTH abuse detection.
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BACKGROUND: Interleukin-1 is pivotal in the pathogenesis of systemic juvenile idiopathic arthritis (JIA). We assessed the efficacy and safety of canakinumab, a selective, fully human, anti-interleukin-1β monoclonal antibody, in two trials. METHODS: In trial 1, we randomly assigned patients, 2 to 19 years of age, with systemic JIA and active systemic features (fever; ≥2 active joints; C-reactive protein, >30 mg per liter; and glucocorticoid dose, ≤1.0 mg per kilogram of body weight per day), in a double-blind fashion, to a single subcutaneous dose of canakinumab (4 mg per kilogram) or placebo. The primary outcome, termed adapted JIA ACR 30 response, was defined as improvement of 30% or more in at least three of the six core criteria for JIA, worsening of more than 30% in no more than one of the criteria, and resolution of fever. In trial 2, after 32 weeks of open-label treatment with canakinumab, patients who had a response and underwent glucocorticoid tapering were randomly assigned to continued treatment with canakinumab or to placebo. The primary outcome was time to flare of systemic JIA. RESULTS: At day 15 in trial 1, more patients in the canakinumab group had an adapted JIA ACR 30 response (36 of 43 [84%], vs. 4 of 41 [10%] in the placebo group; P<0.001). In trial 2, among the 100 patients (of 177 in the open-label phase) who underwent randomization in the withdrawal phase, the risk of flare was lower among patients who continued to receive canakinumab than among those who were switched to placebo (74% of patients in the canakinumab group had no flare, vs. 25% in the placebo group, according to Kaplan-Meier estimates; hazard ratio, 0.36; P=0.003). The average glucocorticoid dose was reduced from 0.34 to 0.05 mg per kilogram per day, and glucocorticoids were discontinued in 42 of 128 patients (33%). The macrophage activation syndrome occurred in 7 patients; infections were more frequent with canakinumab than with placebo. CONCLUSIONS: These two phase 3 studies show the efficacy of canakinumab in systemic JIA with active systemic features. (Funded by Novartis Pharma; ClinicalTrials.gov numbers, NCT00889863 and NCT00886769.).
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On June 26-27, 2006, 60 academic and industry scientists gathered during the PROSAFE workshop to discuss recommendations on taxonomy, antibiotic resistance, in vitro assessment of virulence and in vivo assessment of safety of probiotics used for human consumption. For identification of lactic acid bacteria (LAB) intended for probiotic use, it was recommended that conventional biochemical methods should be complemented with molecular methods and that these should be performed by an expert lab. Using the newly developed LAB Susceptibility test Medium (LSM), tentative epidemiological cut-off values were proposed. It was recommended that potentially probiotic strains not belonging to the wildtype distributions of relevant antimicrobials should not be developed as future products for human or animal consumption. Furthermore, it was recommended that the use of strains harbouring known and confirmed virulence genes should be avoided. Finally, for in vivo assessment of safety by investigating strain pathogenicity in animal models, the rat endocarditis model appeared to be the most reliable model tested in the PROSAFE project. Moreover, consensus was reached for approving the necessity of a human colonisation study in a randomised placebo-controlled double-blind design; however, further discussions are needed on the details of such as study.
Resumo:
The renal site of the natriuretic effect of human, atrial natriuretic peptide (hANP) was studied using clearance techniques in eight salt-loaded normal volunteers undergoing maximal water diuresis. Lithium was used as a marker of proximal sodium reabsorption. According to a two-way, single blind, crossover design, hANP (Met12-(3-28)-eicosahexapeptide, (2 micrograms/min) or its vehicle (Ve) were infused for two hours, followed by a two-hour recovery period. Blood pressure, heart rate and insulin clearance remained unchanged. During hANP infusion, the filtration fraction increased slightly from 19.6 to 24.3% (P less than 0.001), fractional water excretion rose transiently at the beginning of the infusion. Fractional excretion of sodium increased markedly from 2.2% to 7.4% (P less than 0.001) but remained unchanged with Ve. ANP increased fractional excretion of lithium slightly from 46 to 58% (P less than 0.01), while it remained stable at 47% during Ve. The distal tubular rejection fraction of sodium calculated from sodium and lithium clearances rose markedly from 4.7 to 13% (P less than 0.001) and returned to 6.2% at the end of the recovery period. Thus, under salt loading and water diuresis conditions, hANP infusion did not alter GFR, but reduced proximal reabsorption of sodium, and markedly enhanced the fraction of sodium escaping distal tubular reabsorption, suggesting that hANP-induced natriuresis is due, for an important part, to inhibition of sodium reabsorption in the distal nephron.
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BACKGROUND: Thymostimulin is a thymic peptide fraction with immune-mediated cytotoxicity against hepatocellular carcinoma (HCC) in vitro and palliative efficacy in advanced HCC in two independent phase II trials. The aim of this study was to assess the efficacy of thymostimulin in a phase III trial. METHODS: The study was designed as a prospective randomised, placebo-controlled, double-blind, multicenter clinical phase III trial. Between 10/2002 and 03/2005, 135 patients with locally advanced or metastasised HCC (Karnofsky >or=60%/Child-Pugh <or= 12) were randomised to receive thymostimulin 75 mg s.c. 5x/week or placebo stratified according to liver function. Primary endpoint was twelve-month survival, secondary endpoints overall survival (OS), time to progression (TTP), tumor response, safety and quality of life. A subgroup analysis according to liver function, KPS and tumor stage (Okuda, CLIP and BCLC) formed part of the protocol. RESULTS: Twelve-month survival was 28% [95%CI 17-41; treatment] and 32% [95%CI 19-44; control] with no significant differences in median OS (5.0 [95% CI 3.7-6.3] vs. 5.2 [95% CI 3.5-6.9] months; p = 0.87, HR = 1.04 [95% CI 0.7-1.6]) or TTP (5.3 [95%CI 2.0-8.6] vs. 2.9 [95%CI 2.6-3.1] months; p = 0.60, HR = 1.13 [95% CI 0.7-1.8]). Adjustment for liver function, Karnofsky status or tumor stage did not affect results. While quality of life was similar in both groups, fewer patients on thymostimulin suffered from accumulating ascites and renal failure. CONCLUSIONS: In our phase III trial, we found no evidence of any benefit to thymostimulin in the treatment of advanced HCC and there is therefore no justification for its use as single-agent treatment. The effect of thymostimulin on hepato-renal function requires further confirmation. TRIAL REGISTRATION: Current Controlled Trials ISRCTN64487365.
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Passive immunization against β-amyloid (Aβ) has become an increasingly desirable strategy as a therapeutic treatment for Alzheimer's disease (AD). However, traditional passive immunization approaches carry the risk of Fcγ receptor-mediated overactivation of microglial cells, which may contribute to an inappropriate proinflammatory response leading to vasogenic edema and cerebral microhemorrhage. Here, we describe the generation of a humanized anti-Aβ monoclonal antibody of an IgG4 isotype, known as MABT5102A (MABT). An IgG4 subclass was selected to reduce the risk of Fcγ receptor-mediated overactivation of microglia. MABT bound with high affinity to multiple forms of Aβ, protected against Aβ1-42 oligomer-induced cytotoxicity, and increased uptake of neurotoxic Aβ oligomers by microglia. Furthermore, MABT-mediated amyloid plaque removal was demonstrated using in vivo live imaging in hAPP((V717I))/PS1 transgenic mice. When compared with a human IgG1 wild-type subclass, containing the same antigen-binding variable domains and with equal binding to Aβ, MABT showed reduced activation of stress-activated p38MAPK (p38 mitogen-activated protein kinase) in microglia and induced less release of the proinflammatory cytokine TNFα. We propose that a humanized IgG4 anti-Aβ antibody that takes advantage of a unique Aβ binding profile, while also possessing reduced effector function, may provide a safer therapeutic alternative for passive immunotherapy for AD. Data from a phase I clinical trial testing MABT is consistent with this hypothesis, showing no signs of vasogenic edema, even in ApoE4 carriers.
Resumo:
BACKGROUND: Interleukin-1 is pivotal in the pathogenesis of systemic juvenile idiopathic arthritis (JIA). We assessed the efficacy and safety of canakinumab, a selective, fully human, anti-interleukin-1β monoclonal antibody, in two trials. METHODS: In trial 1, we randomly assigned patients, 2 to 19 years of age, with systemic JIA and active systemic features (fever; ≥2 active joints; C-reactive protein, >30 mg per liter; and glucocorticoid dose, ≤1.0 mg per kilogram of body weight per day), in a double-blind fashion, to a single subcutaneous dose of canakinumab (4 mg per kilogram) or placebo. The primary outcome, termed adapted JIA ACR 30 response, was defined as improvement of 30% or more in at least three of the six core criteria for JIA, worsening of more than 30% in no more than one of the criteria, and resolution of fever. In trial 2, after 32 weeks of open-label treatment with canakinumab, patients who had a response and underwent glucocorticoid tapering were randomly assigned to continued treatment with canakinumab or to placebo. The primary outcome was time to flare of systemic JIA. RESULTS: At day 15 in trial 1, more patients in the canakinumab group had an adapted JIA ACR 30 response (36 of 43 [84%], vs. 4 of 41 [10%] in the placebo group; P<0.001). In trial 2, among the 100 patients (of 177 in the open-label phase) who underwent randomization in the withdrawal phase, the risk of flare was lower among patients who continued to receive canakinumab than among those who were switched to placebo (74% of patients in the canakinumab group had no flare, vs. 25% in the placebo group, according to Kaplan-Meier estimates; hazard ratio, 0.36; P=0.003). The average glucocorticoid dose was reduced from 0.34 to 0.05 mg per kilogram per day, and glucocorticoids were discontinued in 42 of 128 patients (33%). The macrophage activation syndrome occurred in 7 patients; infections were more frequent with canakinumab than with placebo. CONCLUSIONS: These two phase 3 studies show the efficacy of canakinumab in systemic JIA with active systemic features. (Funded by Novartis Pharma; ClinicalTrials.gov numbers, NCT00889863 and NCT00886769.).
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OBJECTIVE: Nandrolone is an anabolic steroid widely used in several sports. The numerous nandrolone positive cases in the recent years (International Olympic Committee statistics) led to several studies in the antidoping field. Nevertheless, essential questions pertaining to nandrolone endogenous production, the effects of physical exercise on the excretion of nandrolone metabolites, and contamination from nutritional supplements must still be addressed. The purpose of this study was to evaluate the influence of exhaustive exercises on 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) urinary excretion rates after administration of labeled nandrolone. SETTING AND PARTICIPANTS: A total of 34 healthy male Caucasian volunteers from the Institute of Sports Sciences and Physical Education (University of Lausanne) applied to participate in the study. All subjects were free from any physical drug addiction and were instructed strictly to avoid any nutritional supplement or steroid before and during the study. The participants were randomly dispatched in 2 groups in a double-blind way: a placebo group and a group treated with C-labeled nandrolone. MAIN OUTCOME MEASUREMENTS: The urinary concentrations of the 2 main nandrolone metabolites, 19-NA and 19-NE, were measured using gas chromatography coupled with mass spectrometry. In addition, clinical parameters such as creatinine, total protein, and beta2-microglobuline levels were determined using immunologic assays. RESULTS: After an oral ingestion of a 25 mg 3,4-C2-nandrolone dose, followed by a second identical dose 24 hours later, 19-NA and 19-NE could be detected in the urine for a period of 6 days after the initial intake. Despite several interesting observations, the measurements were very scattered and did not appear to be significantly influenced by exercise sessions in the athlete population. CONCLUSIONS: The results of this study suggest that physical exercise cannot be considered as a reliable parameter that systematically affects nandrolone metabolite concentrations in the urine.
Resumo:
A score system integrating the evolution of efficacy and tolerability over time was applied to a subpopulation of the STRATHE trial, a trial performed according to a parallel group design, with a double-blind, random allocation to either a fixed-dose combination strategy (perindopril/indapamide 2 mg/0.625 mg, with the possibility to increase the dose to 3 mg/0.935 mg, and 4 mg/1.250 mg if needed, n = 118), a sequential monotherapy approach (atenolol 50 mg, followed by losartan 50 mg and amlodipine 5 mg if needed, n = 108), or a stepped-care strategy (valsartan 40 mg, followed by valsartan 80 mg and valsartan 80 mg+ hydrochlorothiazide 12.5 mg if needed, n = 103). The aim was to lower blood pressure below 140/90 mmHg within a 9-month period. The treatment could be adjusted after 3 and 6 months. Only patients in whom the study protocol was strictly applied were included in this analysis. At completion of the trial the total score averaged 13.1 +/- 70.5 (mean +/- SD) using the fixed-dose combination strategy, compared with -7.2 +/- 81.0 using the sequential monotherapy approach and -17.5 +/- 76.4 using the stepped-care strategy. In conclusion, the use of a score system allows the comparison of antihypertensive therapeutic strategies, taking into account at the same time efficacy and tolerability. In the STRATHE trial the best results were observed with the fixed-dose combination containing low doses of an angiotensin enzyme converting inhibitor (perindopril) and a diuretic (indapamide).
Resumo:
RESUME Introduction: Les inhibiteurs de la pompe à protons sont actuellement considérés comme les médicaments de choix pour le traitement des affections peptiques comme l'ulcère gastroduodénal et l'oesophagite de reflux. La rapidité, ainsi que le degré d'inhibition de la sécrétion gastrique acide sont importants pour le contrôle optimal des symptômes ainsi que pour le traitement de ces affections. But : Le but principal de cette étude a été de comparer, chez les sujets asymptomatiques non infectés par H. pylori, par pH-métrie intragastrique de 24 heures, la rapidité et la durée de l'action antisécrétoire de doses uniques de rabéprazole 20 mg, d'oméprazole capsule 20 mg, d'oméprazole en comprimé MUPS (« Multiple Unit Pellet System ») 20 mg, de pantoprazole 40 mg et de lansoprazole 30 mg, respectivement. Matériel et méthodes : Cette étude, effectuée en double aveugle et randomisée, a été conduite de manière croisée chez 18 sujets H. pylori-négatifs. Une pH-métrie de 24 heures a été effectuée le jour de l'administration du médicament (dose unique de rabéprazole 20 mg, de lansoprazole 30mg, de pantoprazole 40 mg, d'oméprazole capsule 20 mg, d'oméprazole MUPS comprimé 20mg, ou de placebo). Résultats : Le pH intragastrique médian (3.4 vs. 2.9, 2.2, 1.9 et 1.8, respectivement; p≤ 0.03) et le temps avec un pH supérieur à 4 pendant les 24 heures suivant la prise du médicament (8.0 heures vs. 7.4, 4.9, 2.9, et 3.0, respectivement; p≤ 0.003) ont été statistiquement plus élevés avec le rabéprazole qu'avec le lansoprazole, le pantoprazole, l'oméprazole capsule, l'oméprazole comprimé MUPS, ou le placebo. Les valeurs du pH pendant les périodes diurnes et nocturnes étaient plus hautes avec le rabeprazole et le lansoprazole qu'avec le pantoprazole, l'oméprazole capsule, et l'oméprazole comprimé MUPS (p≤0.04). Conclusion : Le rabéprazole s'est montré le plus efficace de tous les inhibiteurs de pompe à protons étudiés durant le premier jour de l'administration du médicament. SUMMARY Background: Rapid and consistent acid suppression on the first day of dosing may be important in treating acid-related disorders. Aim: To compare the antisecretory activity and onset of action of single doses of rabeprazole, lansoprazole, pantoprazole, omeprazole capsule, omeprazole multiple unit pellet system (MUPS) tablet and placebo in healthy Helicobacter pylori-negative subjects. Methods: This cross-over, double-blind, randomized study was performed in 18 H. pylori-negative subjects. Twenty-four-hour intragastric pH monitoring was performed on the day of treatment (once-daily dose of rabeprazole 20 mg, lansoprazole 30 mg, pantoprazole 40 mg, omeprazole capsule 20 mg, omeprazole MUPS tablet 20 mg or placebo). Results: The intragastric pH (3.4) and time at pH > 4 during the 24 h post-dose (8.0 h) were significantly greater with rabeprazole than with lansoprazole, pantoprazole, omeprazole capsule, omeprazole MUPS tablet or placebo (P ≤ 0.04 for rabeprazole vs. the others). Daytime and night-time pH values were higher with rabeprazole and lansoprazole than with pantoprazole, omeprazole capsule and omeprazole MUPS tablet (P ≤ 0.04). Conclusion: Rabeprazole was the most potent acid inhibitor of all the proton pump inhibitors tested during the first day of dosing.
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BACKGROUND: The efficacy of cardiac pacing for prevention of syncopal recurrences in patients with neurally mediated syncope is controversial. We wanted to determine whether pacing therapy reduces syncopal recurrences in patients with severe asystolic neurally mediated syncope. METHODS AND RESULTS: Double-blind, randomized placebo-controlled study conducted in 29 centers in the Third International Study on Syncope of Uncertain Etiology (ISSUE-3) trial. Patients were ≥40 years, had experienced ≥3 syncopal episodes in the previous 2 years. Initially, 511 patients, received an implantable loop recorder; 89 of these had documentation of syncope with ≥3 s asystole or ≥6 s asystole without syncope within 12 ± 10 months and met criteria for pacemaker implantation; 77 of 89 patients were randomly assigned to dual-chamber pacing with rate drop response or to sensing only. The data were analyzed on intention-to-treat principle. There was syncope recurrence during follow-up in 27 patients, 19 of whom had been assigned to pacemaker OFF and 8 to pacemaker ON. The 2-year estimated syncope recurrence rate was 57% (95% CI, 40-74) with pacemaker OFF and 25% (95% CI, 13-45) with pacemaker ON (log rank: P=0.039 at the threshold of statistical significance of 0.04). The risk of recurrence was reduced by 57% (95% CI, 4-81). Five patients had procedural complications: lead dislodgment in 4 requiring correction and subclavian vein thrombosis in 1 patient. CONCLUSIONS: Dual-chamber permanent pacing is effective in reducing recurrence of syncope in patients ≥40 years with severe asystolic neurally mediated syncope. The observed 32% absolute and 57% relative reduction in syncope recurrence support this invasive treatment for the relatively benign neurally mediated syncope. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00359203.