Diffuse analgesic effects of unilateral repetitive transcranial magnetic stimulation (rTMS) in healthy volunteers

We investigated the analgesic effects of unilateral repetitive transcranial magnetic stimulation (rTMS) of the motor cortex (M1) or dorsolateral prefrontal cortex (DLPFC) in two models of experimental pain in healthy volunteers. Two studies were carried out in parallel in two groups of 26 paid healthy volunteers. The effects of active or sham rTMS (frequency, 10 Hz; intensity, 80% resting motor threshold) applied to the right M1 or DLPFC were compared in a double-blind randomized cross-over design. In the first series of experiments, we analyzed the effects of rTMS on thermal (heat and cold) detection and pain thresholds measured on both hands and the left foot, by standardized quantitative sensory testing methods. In the second series of experiments, we measured the effects of M1 or DLPFC rTMS on the threshold and recruitment curves of the RIII nociceptive reflex evoked by ipsilateral electrical stimulation of the sural nerve and recorded on the biceps femoris of both lower limbs. In both studies, measurements were taken before and up to 60 min after the end of rTMS. Active rTMS of both M1 and DLPFC significantly increased the thermal pain thresholds, measured for both hands and the left foot, this effect being most marked for cold pain. These effects, which lasted at least 1 h after rTMS, were selective because they were not associated with changes in non-painful thermal sensations. By contrast, the second study showed that rTMS of M1 or DLPFC had no significant effect on the threshold or recruitment curve of the nociceptive flexion RIII reflex. Our findings demonstrate that unilateral rTMS of M1 or DLPFC induces diffuse and selective analgesic effects in healthy volunteers. The lack of effect on the RIII reflex suggests that such analgesic effects may not depend on the activation of descending inhibitory systems. (C) 2009 International Association for the Study of Pain. Published by Elsevier B. V. All rights reserved.

Induction and maintenance of in vivo ventricular fibrillation in rabbits

Aim: To provide new sustainable in vivo models of ventricular fibrillation in rabbits. Methods: New Zealand rabbits were submitted to anaesthesia and mechanical ventilation. after which ventricular fibrillation was induced through electrical stimulation (for 2 min at 100 Hz, with 2-ms pulses, 10 mA. and 10V) directly to the heart. To that end, the animals were divided into two groups: right ventricle (n = 11) and left ventricle (n = 11). In group right ventricle, the thoracic cavity was exposed, and a catheter was introduced into the right ventricle via the right jugular vein. in group left ventricle, the thorax remained closed, and the catheter was introduced into the left ventricle via the left common carotid artery (cervical access). Results: Sustained ventricular fibrillation was achieved in 100% of group right ventricle rabbits (n = 11 and in 82% of group left ventricle rabbits (n = 9). Conclusion: Both models proved appropriate for achieving sustained ventricular fibrillation. However, in view of the invasiveness of the procedure adopted in group right ventricle, the experimental conditions used in group left ventricle seemed more physiological and more effective in inducing sustained ventricular fibrillation. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

RELIABILITY AND VALIDITY OF THE PHOTOGRAMMETRY FOR SCOLIOSIS EVALUATION: A CROSS-SECTIONAL PROSPECTIVE STUDY

Objective: The purpose of this study was to investigate the reliability and validity of photogrammetry in measuring the lateral spinal inclination angles. Methods: Forty subjects (32 female and 8 males) with a mean age of 23.4 +/- 11.2 years had their scoliosis evaluated by radiographs of their trunk, determined by the Cobb angle method, and by photogrammetry. The statistical methods used included Cronbach alpha, Pearson/Spearman correlation coefficients, and regression analyses. Results: The Cronbach a values showed that the photogrammetric measures showed high internal consistency, which indicated that the sample was bias free. The radiograph method showed to be more precise with intrarater reliabilities of 0.936, 0.975, and 0.945 for the thoracic, lumbar, and thoracolumbar curves, respectively, and interrater reliabilities of 0.942 and 0.879 for the angular measures of the thoracic and thoracolumbar segments, respectively. The regression analyses revealed a high determination coefficient although limited to the adjusted linear model between the radiographic and photographic measures. It was found that with more severe scoliosis, the lateral curve measures obtained with the photogrammetry were for the thoracic and lumbar regions (R = 0.619 and 0.551). Conclusions: The photogrammetric measures were found to be reproducible in this study and could be used as Supplementary information to decrease the number of radiographs necessary for the monitoring of scoliosis. (J Manipulative Physiol Ther 2009;32:423-430)

Ranolazine Exerts Potent Effects on Atrial Electrical Properties and Abbreviates Atrial Fibrillation Duration in the Intact Porcine Heart

Introduction: In vitro studies and ambulatory ECG recordings from the MERLIN TIMI-36 clinical trial suggest that the novel antianginal agent ranolazine may have the potential to suppress atrial arrhythmias. However, there are no reports of effects of ranolazine on atrial electrophysiologic properties in large intact animals. Methods and Results: In 12 closed-chest anesthetized pigs, effects of intravenous ranolazine (similar to 9 mu M plasma concentration) on multisite atrial effective refractory period (ERP), conduction time (CT), and duration and inducibility of atrial fibrillation (AF) initiated by intrapericardial acetylcholine were investigated. Ranolazine increased ERP by a median of 45 ms (interquartile range 29-50 ms; P < 0.05, n = 6) in right and left atria compared to control at pacing cycle length (PCL) of 400 ms. However, ERP increased by only 28 (24-34) ms in right ventricle (P < 0.01, n = 6). Ranolazine increased atrial CT from 89 (71-109) ms to 98 (86-121) ms (P = 0.04, n = 6) at PCL of 400 ms. Ranolazine decreased AF duration from 894 (811-1220) seconds to 621 (549-761) seconds (P = 0.03, n = 6). AF was reinducible in 1 of 6 animals after termination with ranolazine compared with all 6 animals during control period (P = 0.07). Dominant frequency (DF) of AF was reduced by ranolazine in left atrium from 11.7 (10.7-20.5) Hz to 7.6 (2.9-8.8) Hz (P = 0.02, n = 6). Conclusions: Ranolazine, at therapeutic doses, increased atrial ERP to greater extent than ventricular ERP and prolonged atrial CT in a frequency-dependent manner in the porcine heart. AF duration and DF were also reduced by ranolazine. Potential role of ranolazine in AF management merits further investigation. (J Cardiovasc Electrophysiol, Vol. 20, pp. 796-802, July 2009).

Performance of Brazilian long and short IQCODE on the screening of dementia in elderly people with low education

Background: Dementia screening in elderly people with low education can be difficult to implement. For these subjects, informant reports using the long (L) (26 items) and short (C) (16 items) versions of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) can be useful. The objective of the present study was to investigate the performance of Brazilian versions of the IQCODE L, S and a new short version (SBr) (15 items) in comparison with the Mini-mental State Examination (MMSE) for dementia screening in elderly people with low education. Methods: Thirty-four patients with mild to moderate dementia, diagnosed according to ICD-10 criteria, and 57 controls were evaluated and divided into three groups based on their socioeconomic status and level of education. Patients were evaluated using the MMSE and the informants were interviewed using the IQCODE by interviewers blind to the clinical diagnosis. Results: Education was correlated with MMSE results (r = 0.280, p = 0.031), but not with the versions of the IQCODE. The performance of the instruments, evaluated by the ROC curves, was very similar, with good internal consistency (Cronbach`s alpha = 0.97). MMSE correctly classified 85.7% of the subjects while the three IQCODE versions (L, S and SBr) correctly classified 91.2% of the subjects. Conclusions: The long, short and the new short Brazilian IQCODE versions can be useful as a screening tool for mild and moderate patients with dementia in Brazil. The IQCODE is not biased by schooling, and it seems to be an adequate instrument for samples with low levels of education.

Mild chronic kidney dysfunction and treatment strategies for stable coronary artery disease

Objective: Our objective was to evaluate the association of chronic kidney dysfunction in patients with multi-vessel chronic coronary artery disease, preserved left ventricular function, and the possible interaction between received treatment and cardiovascular events. Methods: The glomerular filtration rate was determined at baseline on 611 patients who were randomized into three treatment groups: medical treatment, percutaneous coronary intervention, and coronary artery bypass surgery. Incidence of myocardial infarction, angina requiring a new revascularization procedure, and death were analyzed during 5 years in each group. Results: Of 611 patients, 112 (18%) were classified as having normal renal function, 349 (57%) were classified as having mild dysfunction, and 150 (25%) were classified as having moderate dysfunction. There were significant differences among the cumulative overall mortality curves among the three renal function groups. Death was observed more frequently in the moderate dysfunction group than the other two groups (P < .001). Interestingly, in patients with mild chronic kidney dysfunction, we observed that coronary artery bypass treatment presented a statistically higher percentage of event-free survival and lower percentage of mortality than did percutaneous coronary intervention or medical treatment Conclusions: Our results confirm that coronary artery disease accompanied by chronic kidney dysfunction has a worse prognosis, regardless of the therapeutic strategy for coronary artery disease, when renal function is at least mildly impaired. Additionally, our data suggest that the different treatment strategies available for stable coronary artery disease may have differential beneficial effects according to the range of glomerular filtration rate strata.

One-Stage Revision of Infected Total Hip Arthroplasty with Bone Graft

There are many different opinions in the literature regarding the best procedure for revision of infected hip arthroplasty and hence in achieving long-term stabilization of a new implant. Thirty-two patients with 32 loose and infected total hip arthroplasties underwent revision with a bone graft in a 1-stage procedure. The bone graft was used in the acetabulum and femure in 25 patients, in the acetabulum alone in 4 patients and in the femur alone in 3 patients. A metal mesh was necessary in 15 patients to contain the morselized bone graft. At the time of surgical revision, 9 patients had a draining sinus, 6 had a closed sinus, and 17 had never had sinuses in the surgical wound. Antibiotic therapy was administered intravenously and orally for 6 months. Mean follow-up was 103 months (range, 63-183 months), and infection recurred in 2 (6.2%) cases. Further studies are necessary, and continuation of this method is justified.