Alberto Cliquet

Altered left ventricular diastolic function in subjects with spinal cord injury

Study design:This is cross-sectional study.Objectives:The aim of this study is to investigate the cardiac structure and function of subjects with spinal cord injury (SCI) and the impact of metabolic, hemodynamic and inflammatory factors on these parameters.Setting:São Paulo, Brazil.Methods:Sixty-five nondiabetic, nonhypertensive, sedentary, nonsmoker men (34 with SCI and 31 healthy subjects) were evaluated by medical history, anthropometry, laboratory tests, analysis of hemodynamic and inflammatory parameters and echocardiography.Results:Subjects with SCI had lower systolic blood pressure and higher levels of C-reactive protein and tumor necrosis factor receptors than the healthy ones. Echocardiography data showed that the SCI group presented similar left ventricular (LV) structural and systolic parameters, but lower initial diastolic velocity (Em) (9.2±0.5 vs 12.3±0.5u2009cmu2009s−1; P<0.001) and higher peak early inflow velocity (E)/Em ratio (7.7±0.5 vs 6.1±0.3; P=0.009) compared with the able-bodied group, even after adjustment for systolic blood pressure and C-reactive protein levels. Furthermore, injured subjects with E/Em >8 had lower peak spectral longitudinal contraction (Sm) (9.0±0.7 vs 11.6±0.4u2009cmu2009s−1; P<0.001) and cardiac output (4.2±0.2 vs 5.0±0.2u2009lu2009min−1; P=0.029), as well as higher relative wall thickness (0.38±0.01 vs 0.35±0.01; P=0.005), than individuals with SCI with E/Em<8, but similar age, body mass index, blood pressure, injury level, metabolic parameters and inflammatory marker levels.Conclusion:Subjects with SCI presented impaired LV diastolic function in comparison with able-bodied ones. Moreover, worse LV diastolic function was associated with a pattern of LV concentric remodeling and subclinical decreases in systolic function among injured subjects. Overall, these findings might contribute to explain the increased cardiovascular risk reported for individuals with SCI.

Physical activity is associated with improved subclinical atherosclerosis in spinal cord injury subjects independent of variation in traditional risk factors.

injury subjects independent of variation in traditional risk factors☆ Jose R. Matos-Souza , Anselmo A. Silva , Luis F. Campos , Debora Goulart , Roberto Schreiber , Guilherme de Rossi , Jose A. Pio-Magalhaes , Mauricio Etchebehere , Jose I. Gorla , Alberto Cliquet Jr. , Wilson Nadruz Jr. a,⁎ a Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, SP, Brazil b School of Physical Education, State University of Campinas, Campinas, SP, Brazil c Department of Orthopaedics, School of Medical Sciences, State University of Campinas, Campinas, SP, Brazil d Department of Electrical Engineering, University of Sao Paulo (USP), Sao Carlos, SP, Brazil

Oxidized low-density lipoprotein, matrix-metalloproteinase-8 and carotid atherosclerosis in spinal cord injured subjects.

OBJECTIVEnPrevious reports have indicated that subjects with chronic spinal cord injury (SCI) exhibit increased cardiovascular risk compared to able-bodied individuals. This study investigated the relationship between plasmatic oxidized low-density lipoprotein (OxLDL), matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) levels and vascular remodeling in SCI subjects and the role of physical activity in this regard.nnnMETHODSnWe studied 42 men with chronic (≥2 years) SCI [18 sedentary (S-SCI) and 24 physically active (PA-SCI)] and 16 able-bodied men by clinical, anthropometric, laboratory, and carotid intima-media thickness (IMT) analysis. All enrolled subjects were normotensive, non-diabetics, non-smokers and normolipemic. Plasmatic OxLDL, MMP-2, MMP-8, MMP-9, TIMP-1 and TIMP-2 levels were determined by enzyme-linked immunosorbent assay.nnnRESULTSnCarotid IMT, IMT/diameter ratio and OxLDL levels of PA-SCI and able-bodied subjects were statistically similar. Conversely, S-SCI subjects exhibited higher IMT, IMT/diameter ratio and OxLDL levels compared to PA-SCI (p < 0.01, p < 0.001 and p = 0.01, respectively) and able-bodied (p < 0.001 for all) individuals. Results of bivariate correlation analysis including all injured subjects showed that carotid IMT and IMT/diameter ratio only correlated with OxLDL, MMP-8 and MMP-8/TIMP-1 ratio. Further stepwise regression analysis adjusted for the presence or not of physical activity and age showed that OxLDL was associated with carotid IMT and IMT/diameter ratio, while MMP-8 was associated with IMT/diameter ratio in SCI individuals.nnnCONCLUSIONSnPlasmatic OxLDL and MMP-8 levels are associated with carotid atherosclerosis and there is an interaction among physical inactivity, atherosclerosis and OxLDL in SCI individuals.

Energy expenditure during rest and treadmill gait training in quadriplegic subjects

Study design:The analysis of oxygen uptake (VO2) and energy consumption in quadriplegics after 6 months of treadmill gait with neuromuscular electrical stimulation (NMES).Objectives:To compare metabolic responses in quadriplegics after 6 months of treadmill training, with NMES (30–50% body weight relief), with quadriplegics who did not perform gait.Setting:Ambulatory of University Hospital, Brazil.Methods:Quadriplegics were separated into gait and control groups (CGs). On inclusion, all subjects performed VO2 test. In the gait group (GG) (n=11), the protocol consisted of 8u2009min of rest, 10u2009min of treadmill walking using NMES and 10u2009min of recovery. In the CG (n=10), testing consisted of 8u2009min rest, 15u2009min of quadriceps endurance exercise in sitting position with NMES and 10u2009min recovery. VO2, carbon dioxide production (VCO2) and energy consumption were measured. The GG performed 6 months of treadmill training, using NMES, for 20u2009min, twice a week. The CG did not practice any activity with NMES, performing conventional physiotherapy only; the CG was stimulated only during the cardiorespiratory test.Results:All parameters increased significantly for the GG: 36% for VO2 (l/min), 43% for VCO2 (l/min) and 32.5% for energy consumption (J/kg/s). For the CG, during knee extension exercise, VO2 increased without changes in the energy consumption (P<0.05); smaller values were obtained for all parameters when compared to those obtained during gait.Conclusions:Quadriplegic gait was efficient towards increasing VO2 and energy consumption, which can decrease the risk of cardiovascular diseases.

A Hybrid System for Upper Limb Movement Restoration in Quadriplegics

Generally, quadriplegic individuals have difficulties performing object manipulation. Toward satisfactory manipulation, reach and grasp movements must be performed with voluntary control, and for that, grasp force feedback is essential. A hybrid system aiming at partial upper limb sensory-motor restoration for quadriplegics was built. Such device is composed of an elbow dynamic orthosis that provides elbow flexion/extension (range was approximately from 20 degrees to 120 degrees , and average angular speed was approximately 15 degrees /s) with forearm support, a wrist static orthosis and neuromuscular electrical stimulation for grasping generation, and a glove with force sensors that allows grasping force feedback. The glove presents two user interface modes: visual by light emitting diodes or audio emitted by buzzer. Voice control of the entire system (elbow dynamic orthosis and electrical stimulator) is performed by the patient. The movements provided by the hybrid system, combined with the scapular and shoulder movements performed by the patient, can aid quadriplegic individuals in tasks that involve reach and grasp movements.

Posture Influence on the Pendulum Test of Spasticity in Patients with Spinal Cord Injury

The study aims to investigate the influence of different postures on spasticity results by pendulum test in patients with spinal cord injury (SCI). The setting was at the University of Campinas (UNICAMP), Campinas, SP, Brazil. Five individuals with SCI and five individuals in the control group were included. All individuals went through the pendulum test in three different positions: supine, semi-supine at an angle of 30°, and sitting up at an angle of 60°. An electrogoniometer was attached to the right leg for measurement of knee joint angles. All situations were performed five times. Blood pressure was monitored during tests. Relaxation index (RI), normalized relaxation index (RIn), test duration in seconds, initial flexion angle, and resting angle were analyzed at three different positions. Results were compared between different positions, and statistically no differences were found. In individuals with SCI, RI (1.83u2009±u20090.2), RIn (1.14u2009±u20090.13), and test duration values (13.95u2009±u20094.14), in sitting up position, were similar to the control group results. In sitting up position, patients showed spasticity reduction. However, the other two postures produce pain and increase blood pressure in patients with tetraplegia. Therefore, these postures should be avoided in patients with lesions above T6, due to possible autonomic dysreflexia symptoms.

Matrix metalloproteinases and left ventricular function and structure in spinal cord injured subjects.

Subjects with spinal cord injury (SCI) exhibit impaired left ventricular (LV) diastolic function, which has been reported to be attenuated by regular physical activity. This study investigated the relationship between circulating matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) and echocardiographic parameters in SCI subjects and the role of physical activity in this regard. Forty-two men with SCI [19 sedentary (S-SCI) and 23 physically-active (PA-SCI)] were evaluated by clinical, anthropometric, laboratory, and echocardiographic analysis. Plasmatic pro-MMP-2, MMP-2, MMP-8, pro-MMP-9, MMP-9, TIMP-1 and TIMP-2 levels were determined by enzyme-linked immunosorbent assay and zymography. PA-SCI subjects presented lower pro-MMP-2 and pro-MMP-2/TIMP-2 levels and improved markers of LV diastolic function (lower E/Em and higher Em and E/A values) than S-SCI ones. Bivariate analysis showed that pro-MMP-2 correlated inversely with Em and directly with E/Em, while MMP-9 correlated directly with LV mass index and LV end-diastolic diameter in the whole sample. Following multiple regression analysis, pro-MMP-2, but not physical activity, remained associated with Em, while MMP-9 was associated with LV mass index in the whole sample. These findings suggest differing roles for MMPs in LV structure and function regulation and an interaction among pro-MMP-2, diastolic function and physical activity in SCI subjects.

Ambulatory blood pressure is associated with subclinical atherosclerosis in spinal cord injury subjects

injury subjects☆ Juliane D. Seabra-Garcez , Jose R. Matos-Souza , Debora Goulart , Karla R. Pithon , Eduardo Abib , Mauricio Etchebehere , Alberto Cliquet Jr. , Wilson Nadruz Jr. a,⁎ a Department of Internal Medicine, School of Medical Sciences, University of Campinas, Campinas, SP, Brazil b Department of Orthopaedics, School of Medical Sciences, University of Campinas, Campinas, SP, Brazil c Department of Electrical Engineering, University of Sao Paulo (USP), Sao Carlos, SP, Brazil

Experiencing Functional Electrical Stimulation Roots on Education, and Clinical Developments in Paraplegia and Tetraplegia With Technological Innovation

Cybernetics-based concepts can allow for complete independence for paralyzed individuals, including sensory motor recovery. Spinal cord injuries are responsible for a huge stress on health and a financial burden to society. This article focuses on novel procedures such as functional diagnosis for paraplegics and tetraplegics, cybertherapies toward lessening comorbidities such as cardiovascular diseases, osteoporosis, etc., and the production of new technology for upper and lower limb control. Functional electrical stimulation reflects a unique opportunity for bipedal gait to be achieved by paraplegics and tetraplegics. Education and training of undergraduates and postgraduates in engineering and life sciences have also been a major aim of this work.

Brain Tumor Segmentation in Magnetic Resonance Images using Genetic Algorithm Clustering and AdaBoost Classifier.

We present a technique for automatic brain tumor segmentation in magnetic resonance images, combining a modified version of a Genetic Algorithm Clustering method with an AdaBoost Classifier. In a group of 42 FLAIR images, segmentations produced by the algorithm were compared to the ground truth information produced by radiologists. The mean Dice similarity coefficient reached by the algorithm was 70.3%. In most cases, the AdaBoost classifier increased the quality of the segmentation, improving, on average, the DSC in about 10%. Our implementation of the Genetic Algorithm Clustering method presents improvements compared to the original method. The use of a fixed, small number of groups and smaller population allowed for less computational effort. In addition, adaptive restriction in the initial segmentation was achieved by using the information of the groups with highest and 2nd-highest mean intensities. By exploring intensity and spatial information of the pixels, the AdaBoost classifier improved segmentation results.