Rationale and design of a randomized placebo-controlled trial assessing the effects of etiologic treatment in Chagas` cardiomyopathy: The BENznidazole Evaluation For Interrupting Trypanosomiasis (BENEFIT)

Background Benznidazole is effective for treating acute and chronic (recently acquired) Tryponosoma cruzi infection (Chagas` disease). Recent data indicate that parasite persistence plays a pivotal role in the pathogenesis of chronic Chagas` cardiomyopathy. However, the efficacy of trypanocidal therapy in preventing clinical complications in patients with preexisting cardiac disease is unknown. Study Design BENEFIT is a multicenter, randomized, double-blind, placebo-controlled clinical trial of 3,000 patients with Chagas` cardiomyopathy in Latin America. Patients are randomized to receive benznidazole (5 mg/kg per day) or matched placebo, for 60 days. The primary outcome is the composite of death; resuscitated cardiac arrest; sustained ventricular tachycardia; insertion of pacemaker or cardiac defibrillator; cardiac transplantation; and development of new heart failure, stroke, or systemic or pulmonary thromboembolic events. The average follow-up time will be 5 years, and the trial has a 90% power to detect a 25% relative risk reduction. The BENEFIT program also comprises a substudy evaluating the effects of benznidazole on parasite clearance and an echo substudy exploring the impact of etiologic treatment on left ventricular function. Recruitment started in November 2004, and >1,000 patients have been enrolled in 35 centers from Argentina, Brazil, and Colombia to date. Conclusion This is the largest trial yet conducted in Chagas` disease. BENEFIT will clarify the role of trypanocidal therapy in preventing cardiac disease progression and death.

Relationship among eccentric hip and knee torques, symptom severity and functional capacity in females with patellofemoral pain syndrome

Objective: To determine the relationships between eccentric hip and knee torques, symptom severity and functional capacity in females with patellofemoral pain syndrome (PFPS). Design: Within-subject correlational study. Setting: University biomechanics laboratory. Participants: 10 females diagnosed with PFPS. Main outcome measures: Eccentric strength of the hip abductors and lateral rotators, and knee extensors were assessed using an isokinetic dynamometer. A 10-cm visual analog scale was used to determine usual knee pain in the last week. The Anterior Knee Pain Scale (AKPS) was used to determine the functional capacity of the patients. Results: The study found that the greater the eccentric knee extensor and hip lateral rotator torques, the higher the functional capacity of the patients (p = 0.02, r = 0.72; p = 0.02, r = 0.72). It was also shown that the greater hip lateral rotator torque, the less the usual pain reported in the last week (p = 0.004, r = -0.84). Despite the lack of statistical significance (p = 0.11), it was also found a modest negative relationship between the eccentric knee extensor torque and the usual pain reported in the last week (r = -0.56) that was considered clinically meaningful (d = 1.4). Conclusions: This study showed that eccentric knee extensor and hip lateral rotator torques were associated with functional capacity and pain level in females with PFPS. Further investigations should be carried out to verify the effects of an intervention program focused on the eccentric action of these muscles with respect to the symptoms in patients with PFPS. (C) 2011 Elsevier Ltd. All rights reserved.

The use of different doses of metamizol for post-operative analgesia in dogs

Objective To evaluate the post-operative analgesic effect of metamizol (dipyrone) administered intravenously at three different doses (15 mg kg(-1), 25 mg kg(-1) and 35 mg kg(-1)) compared to placebo in dogs undergoing ovariohysterectomy. Study design Prospective, comparative, randomized. blinded trial. Animals Forty healthy bitches, aged 1-6 years, weighing 10-35 kg Methods The animals were randomly divided into four groups and received their respective treatments immediately after surgery: placebo group (0.9% saline solution), D15 group (metamizol 15 mg kg(-1) IV), D25 group (metamizol 25 mg kg(-1) IV), D35 group (metamizol 35 mg kg(-1) IV). The following variables were measured: sedation, pulse rate (PR). respiratory rate (f(R)). arterial blood pressure (ABP), plasma catecholamines. serum cortisol, blood urea nitrogen (BUN) and creatinine metabolites. albumin, alanine aminotransferase (ALT), alkaline phosphatase (ALP). hemogram. platelet counts and level of analgesia which was assessed by visual analog (VAS). descriptive and behavioral scales. Patients were monitored for 48 hours after the administration of the analgesic agent. Rescue analgesia (tramadol, 2 mg kg(-1), intramuscularly) was provided for animals with pain scores >= 4, as determined by the VAS or descriptive scale. Results The D25 and D35 groups showed equivalent post-operative analgesia, as shown by decreased pain scores, according to the three different pain scales, and fewer animals that required rescue analgesia. Significantly lower serum cortisol concentrations were observed in the D25 and D35 groups when compared to the placebo and D15 groups. No hematologic, renal, hepatic or clinical adverse effects were observed during the treatment. Conclusions and clinical relevance Metamizol administered intravenously at 25 or 35 mg kg(-1) can provide adequate post-operative analgesia in bitches undergoing ovariohysterectomy.