THE SUMMATION OF VOLUNTARY AND ELECTRICAL ELICITED STIMULUS INCREASES JOINT TORQUE?

The aim of this study is to analyze the effect of neuromuscular electrical stimulation (NMES) on myoelectrical activity and on joint torque during isometric plantar flexion contraction. Ten healthy young adult subjects participate in this study. The electrodes for NMES are placed along posterior thigh along ciatic nerve trajectory. It is measured the myoelectrical activity and the isometric torque generated by ankle plantar flexion with an isokinetic dynamometer. The conditions of isometric contractions are maximum isometric voluntary contraction (MIVC), NMES, and association of both (MIVC+NMES). The results show lower torque during NMES and larger SOL activity compare to the others. Besides, in order to keep the same objective task (to produce the same level of torque), neuromuscular adaptations are necessary on the common drive.

Age-related difference on weight transfer during unconstrained standing

The ability to transfer weight from one lower limb to the other is essential for the execution of daily life activities and little is known about how weight transfer during unconstrained natural standing is affected by age. This study examined the weight transfer ability of elderly individuals during unconstrained standing (for 30 mill) in comparison to young adults. The subjects (19 healthy elderly adults, range 65-80 years, and 19 healthy young adults, range 18-30 years) stood with each foot on a separate force plate and were allowed to change their posture freely at any time. The limits of stability and base of support width during standing, measures of mobility (using the timed up and go and the preferred walking speed tests), and fear of falling were also measured. In comparison to the young adults, during unconstrained standing the elderly adults produced four times fewer weight transfers of large amplitude (greater than,half of their body weight). The limits of stability and base of support width were significantly smaller for the elderly adults but there were no significant differences in the measures of mobility and in the fear of falling score compared to young adults. The observed significant age-related decrease in the use of weight transfer during unconstrained standing, despite any difference in the measured mobility of the subjects, suggests that this task reveals unnoticed and subtle differences in postural control, which may help to better understand age related impairments in balance that the elderly population experiences. (C) 2010 Elsevier B.V. All rights reserved.

Effects of joint immobilization on standing balance

We investigated the effect of joint immobilization on the postural sway during quiet standing. We hypothesized that the center of pressure (COP), rambling, and trembling trajectories would be affected by joint immobilization. Ten young adults stood on a force plate during 60 s without and with immobilized joints (only knees constrained, CK; knees and hips, CH; and knees, hips, and trunk, CT). with their eyes open (OE) or closed (CE). The root mean square deviation (RMS, the standard deviation from the mean) and mean speed of COP, rambling, and trembling trajectories in the anterior-posterior and medial-lateral directions were analyzed. Similar effects of vision were observed for both directions: larger amplitudes for all variables were observed in the CE condition. In the anterior-posterior direction, postural sway increased only when the knees, hips, and trunk were immobilized. For the medial-lateral direction, the RMS and the mean speed of the COP, rambling, and trembling displacements decreased after immobilization of knees and hips and knees, hips, and trunk. These findings indicate that the single inverted pendulum model is unable to completely explain the processes involved in the control of the quiet upright stance in the anterior-posterior and medial-lateral directions. (C) 2009 Elsevier B.V. All rights reserved.

Leg preference and interlateral performance asymmetry in soccer player children

Strength of leg peference and interlateral asymmetry in kinematics of kicking a ball for power were assessed in 6- to 10-year-old right-footed soccer player children. Leg preference was evaluated separately for three task categories: balance stabilization, soccer related mobilization, and general mobilization. The results showed that while both categories of mobilization tasks were featured by a consistent preference for the right leg, in stabilization tasks we observed lower scores and greater interindividual variability of leg preference. No effect of age was detected on leg preference. Analysis of peak foot velocity revealed similar increment of performance of the right and left legs from the ages 6-8 to 10 years. This finding supports the notion of stable Magnitude of interlateral asymmetries of performance during motor development. (C) 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 799-806, 2008.

Biomechanical characteristics of elderly individuals walking on land and in water

In this study, we examined Spatial-temporal gait stride parameters, lower extremity joint angles, ground reaction forces (GRF) components, and electromyographic activation patterns of 10 healthy elderly individuals (70 +/- 6 years) walking in water and on land and compared them to a reference group of 10 younger adults (29 +/- 16 years). They all walked at self-selected comfortable speeds both on land and while immersed in water at the Xiphoid process level. Concerning the elderly individuals, the main significant differences observed were that they presented shorter stride length, slower speed, lower GRF values, higher horizontal impulses, smaller knee range of motion, lower ankle dorsiflexion, and more knee flexion at the stride`s initial contact in water than on land. Concerning the comparison between elderly individuals and adults, elderly individuals walked significantly slower on land than adults but both groups presented the same speed walking in water. In water, elderly individuals presented significantly shorter stride length, lower stride duration, and higher stance period duration than younger adults. That is, elderly individuals` adaptations to walking in water differ from those in the younger age group. This fact should be considered when prescribing rehabilitation or fitness programs for these populations. (C) 2006 Elsevier Ltd. All rights reserved.

Kinematic, kinetic and EMG patterns during downward squatting

The aim of this study was to investigate the kinematic, kinetic, and electromyographic pattern before, during and after downward squatting when the trunk movement is restricted in the sagittal plane. Eight healthy subjects performed downward squatting at two different positions, semisquatting (40 degrees knee flexion) and half squatting (70 degrees knee flexion). Electromyographic responses of the vastus medialis oblique, vastus medialis longus, rectus femoris, vastus lateralis, biceps femoris, semitendineous, gastrocnemius lateralis, and tibialis anterior were recorded. The kinematics of the major joints were reconstructed using an optoelectronic system. The center of pressure (COP) was obtained using data collected from one force plate, and the ankle and knee joint torques were calculated using inverse dynamics. In the upright position there were small changes in the COP and in the knee and ankle joint torques. The tibialis anterior provoked the disruption of this upright position initiating the squat. During the acceleration phase of the squat the COP moved posteriorly, the knee joint torque remained in flexion and there was no measurable muscle activation. As the body went into the deceleration phase, the knee joint torque increased towards extension with major muscle activities being observed in the four heads of the quadriceps. Understanding these kinematic, kinetic and EMG strategies before, during and after the squat is expected to be beneficial to practitioners for utilizing squatting as a task for improving motor function. (C) 2006 Elsevier Ltd. All rights reserved.

Joint forces and torques when walking in shallow water

This study reports for the first time an estimation of the internal net joint forces and torques on adults` lower limbs and pelvis when walking in shallow water, taking into account the drag forces generated by the movement of their bodies in the water and the equivalent data when they walk on land. A force plate and a video camera were used to perform a two-dimensional gait analysis at the sagittal plane of 10 healthy young adults walking at comfortable speeds on land and in water at a chest-high level. We estimated the drag force on each body segment and the joint forces and torques at the ankle, knee, and hip of the right side of their bodies using inverse dynamics. The observed subjects` apparent weight in water was about 35% of their weight on land and they were about 2.7 times slower when walking in water. When the subjects walked in water compared with walking on land, there were no differences in the angular displacements but there was a significant reduction in the joint torques which was related to the water`s depth. The greatest reduction was observed for the ankle and then the knee and no reduction was observed for the hip. All joint powers were significantly reduced in water. The compressive and shear joint forces were on average about three times lower during walking in water than on land. These quantitative results substantiate the use of water as a safe environment for practicing low-impact exercises, particularly walking. (C) 2011 Elsevier Ltd. All rights reserved.

Strength training increases walking tolerance in intermittent claudication patients: randomized trial

Objective: To analyse the effects of strength training (ST) in walking capacity in patients with intermittent claudication (IC) compared with walking training (WT) effects. Methods. Thirty patients with IC were randomized into ST and WT. Both groups trained twice a week for 12 weeks at the same rate of perceived exertion. ST consisted of three sets of 10 repetitions of whole body exercises. WT consisted of 15 bouts of 2-minute walking. Before and after the training program walking capacity, peak VO(2), VO(2) at the first stage of treadmill test, ankle brachial index, ischemic window, and knee extension strength were measured. Results: ST improved initial claudication distance (358 +/- 224 vs 504 +/- 276 meters; P < .01), total walking distance (618 +/- 282 to 775 +/- 334 meters; P < .01), VO(2), at the first stage of treadmill test (9.7 +/- 2.6 vs 8.1 +/- 1.7 mL . kg(-1) . minute; P < .01), ischemic window (0.81 +/- 1.16 vs 0.43 +/- 0.47 mm Hg minute meters(-1); P = .04), and knee extension strength (19 +/- 9 vs 21 +/- 8 kg and 21 +/- 9 vs 23 +/- 9; P < .01). Strength increases correlated with the increase in initial claudication distance (r = 0.64; P = .01.) and with the decrease ill VO(2) measured at the first stage of the treadmill test (r = -0.52; P = .04 and r = -0.55; P = .03). Adaptations following ST were similar to the ones observed after WT; however, patients reported lower pain during ST than WT (P < .01). Conclusion: ST improves functional limitation similarly to WT but it produces lower pain, suggesting that this type of exercise could be useful and should be considered in patients with IC. (J Vase Surg 2010;51:89-95.)

COMPARATIVE STUDY OF THE SENSITIVITY OF DIABETIC LOWER EXTREMITIES WITH AND WITHOUT ULCERS USING THE PSSD (TM)

Introduction To determine and compare thresholds of cutaneous sensitivity of lower extremities in diabetic patients with an ulcer on only one lower extremity Methods and Materials The study group included 20 patients with mean age of 61 6 and average time with diabetes of 12 4 years All patients were previously tested using Semmes-Weinstein monofilament 5 07 Sensitivity was evaluated using the two point discrimination test and the PSSD (TM) (Pressure-Specified Sensory Device) in order to assess touch thresholds in a quantitative manner, in g/mm(2) Three skin areas were tested hallux pulp, dorsum of foot and medial heel, including four tests 1 point static, 1 point moving, 2 points static and 2 points moving Results Mean 2 point discrimination distance in mm was higher in feet with ulcers, but the difference between extremities was only statistically significant for the hallux. With the PSSD (TM), all patients had higher pressure thresholds in feet with ulcers when compared with feet without ulcers, in all tests, with statistical significance Conclusion The PSSD (TM) was able to differentiate levels of sensation between extremities with and without ulcers in diabetic patients, with statistical significance

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.

Morphological and morphometric appraisal of the spermatophore of the southern hermit crab Isocheles sawayai Forest and Saint Laurent, 1968 (Anomura: Diogenidae), with comments on gonopores in both sexes

The spermatophore morphology of the hermit crab Isocheles sawayai from Southwestern Atlantic (Brazil) is described. The spermatophores show similarities with those described for other members of the family Diogenidae, especially with the recently described Loxopagurus loxochelis. The spermatophore is composed of three major regions: a sperm filled head or ampulla, a columnar stalk and a foot or pedestal. The spermatophores show specific morphology in having a circular ampulla, and a constriction or neck between the ampulla (100 mu m) and the thin (27 mu m), long stalk (500 mu m). The stalk penetrates less than half way into the spermatophore head. Most spermatophores show one or the small posterior projections on the underside of the ampulla as being bigger than the other, making it asymmetrical. The size of the spermatophore is related to hermit crab size with direct relationships found between spermatophore ampulla width, total length, and peduncle length with shield length of the hermit crab. The morphological characteristics of the spermatophore of L sawayai. are species-specific distinguishing it from other members of the family, and are useful to infer further phylogenetic relationships. (C) 2008 Elsevier GmbH. All rights reserved.

Effects of microinjections of apomorphine and haloperidol into the inferior colliculus on the latent inhibition of the conditioned emotional response

Electrical or chemical stimulation of the inferior colliculus (IC) induces fear-like behaviors. More recently, consistent evidence has shown that electrical stimulation of the central nucleus of the IC supports Pavlovian conditioning and latent inhibition (Li). LI is characterized by retardation in conditioning and also by an impaired ability to ignore irrelevant stimuli, after a non-reinforced pre-exposure to the conditioned stimulus. LI has been proposed as a behavioral model of cognitive abnormalities seen in schizophrenia. The aim of the present study was to determine whether dopaminergic mechanisms in the IC are involved in LI of the conditioned emotional response (CER). To induce LI, a group of rats was pre-exposed (PE) to six tones in two sessions, while rats that were not pre-exposed (NPE) had two sessions without tone presentations. The conditioning consisted of two tone presentations to the animal, followed immediately by a foot shock. PE and NPE rats received IC microinjections of physiological saline, the dopaminergic agonist apomorphine (9.0 mu g/0.5 mu L/side), or the dopaminergic antagonist haloperidol (0.5 mu g/0.5 mu L/side) before both pre-exposure and conditioning. During the test, the PE rats that received saline or haloperidol had a lower suppression of the licking response compared to NPE rats that received vehicle or haloperidol, indicating that latent inhibition was induced. There was no significant difference in the suppression ratio in rats that received apomorphine injections into the IC, indicating reduced latent inhibition. These results suggest that dopamine-mediated mechanisms of the IC are involved in the development of LI. (C) 2008 Elsevier Inc. All rights reserved.

GABAergic REGULATION OF AUDITORY SENSORY GATING IN LOW- AND HIGH-ANXIETY RATS SUBMITTED TO A FEAR CONDITIONING PROCEDURE

The inferior colliculus (IC) is primarily involved in the processing of acoustic stimuli, being in a position to send auditory information to motor centers that participate in behaviors such as prey catching and predators` avoidance The role of the central nucleus of the IC (CIC) on fear and anxiety has been suggested on the basis that rats are able to engage in tasks to decrease the aversiveness of CIC stimulation, increased Fos immunolabeling during diverse aversive states and increased CIC auditory evoked potentials (AEP) induced by conditioned fear stimuli Additionally it was shown that brainstem AEP, represented by wave V, for which the main generator is the IC, is increased during experimentally induced anxiety Rats segregated according to their low or high emotional reactivity have been used as an important tool in the study of fear and anxiety The IC contains a high density of GABA receptors Since the efficacy of an anxiolytic compound is a function of the animal`s anxiety level, it is possible that GABA-benzodiazepine (Bzp) agents affect LA and HA animals differently In this study we investigated the GABA-Bzp influence on the modulation of AEP in rats with low (LA) or high-anxiety (HA) levels, as assessed by the elevated plus maze test (EPM) GABA-Bzp modulation on the unconditioned AEP response was analyzed by using intra CIC injections (0 2 mu l) of the GABA-Bzp agonists muscimol (121 ng) and diazepam (30 mu g) or the GABA inhibitors bicuculline (10 ng) and semicarbazide (7 mu g) In a second experiment, we evaluate the effects of contextual aversive conditioning on AEP using foot shocks as unconditioned stimuli On the unconditioned fear paradigm GABA inhibition in creased AEP in LA rats and decreases this measure in HA counterparts Muscimol was effective in reducing AEP in both LA and HA rats Contextual fear stimuli increased the magnitude of AEP In spite of no effect obtained with diazepam in LA rats the drug inhibited AEP in HA animals The specificity of the regulatory mechanisms mediated by GABA Bzp for the ascending neurocircuits responsible for the acquisition of aversive information in LA and HA animals shed light on the processing of sensory information underlying the generation of defensive reactions (C) 2010 IBRO Published by Elsevier Ltd All rights reserved

An 18-Week, Prospective, Randomized, Double-Blind, Multicenter Study of Amlodipine/Ramipril Combination Versus Amlodipine Monotherapy in the Treatment of Hypertension: The Assessment of Combination Therapy of Amlodipine/Ramipril (ATAR) Study

Background: A combination of antihypertensive agents of different drug classes in a fixed-dose combination (FDC) may offer advantages in terms of efficacy, tolerability, and treatment compliance. Combination of a calcium channel blocker with an angiotensin-converting enzyme inhibitor may act synergistically to reduce blood pressure (BP). Objective: The aim of this study was to compare the efficacy and tolerability of an amlodipine/ramipril FDC with those of amlodipine monotherapy. Methods: This 18-week, prospective, randomized, double-blind study was conducted at 8 centers across Brazil. Patients with stage 1 or 2 essential hypertension were enrolled. After a 2-week placebo run-in phase, patients received amlodipine/ramipril 2.5/2.5 mg or amlodipine 2.5 mg, after which the doses were titrated, based on BP, to 515 then 10/10 mg (amlodipme/ramipril) and 5 then 10 mg (amiodipine). The primary end point was BP measured in the intent-to-treat (ITT) population. Hematology and serum biochemistry were assessed at baseline and study end. Tolerability was assessed using patient interview, laboratory analysis, and physical examination, including measurement of ankle circumference to assess peripheral edema. Results: A total of 222 patients completed the study (age range, 40-79 years; FDC group, 117 patients [mean dose, 7.60/7.60 mg]; monotherapy, 105 patients [mean dose, 7.97 mg]). The mean (SD) changes in systolic BP (SBP) and diastolic BP (DBP), as measured using 24-hour ambulatory blood pressure monitoring (ABPM) and in the physician`s office, were significantly greater with combination therapy than monotherapy, with the exception of office DBP (ABPM, -20.76 [1.25] vs -15.80 [1.18] mm Hg and -11.71 [0.78] vs -8.61 [0.74] mm Hg, respectively [both, P = 0.004]; office, -27.51 [1.40] vs -22.84 [1.33] min Hg [P = 0.012] and -16.41 [0.79] vs -14.64 [0.75] mm Hg [P = NS], respectively). In the ITT analysis, the mean changes in ambulatory, but not office-based, BP were statistically significant (ABPM: SBP, -20.21 [1.14] vs -15.31 [1.12] mm Hg and DBP, -11.61 [0.72] vs -8.42 [0.70] mm Hg, respectively [both, P = 0.002]; office: SBP, -26.60 [1.34] vs -22.97 [1.30] mm Hg and DBP, -16.48 [0.78] vs -14.48 [0.75] mm Hg [both, P = NS]). Twenty-nine patients (22.1%) treated with combination therapy and 41 patients (30.6%) treated with monotherapy experienced >= 1 adverse event considered possibly related to study drug. The combmation-therapy group had lower prevalence of edema (7.6% vs 18.7%; P = 0.011) and a similar prevalence of dry cough (3.8% vs 0.8%; P = NS). No clinically significant changes in laboratory values were found in either group. Conclusions: In this population of patients with essential hypertension, the amlodipine/ramipril FDC was associated with significantly reduced ambulatory and office-measured BP compared with amlodipine monotherapy, with the exception of office DBP. Both treatments were well tolerated. (Clin Ther. 2008;30: 1618-1628) (C) 2008 Excerpta Medica Inc.

Limb Salvage Using Bypass to the Perigeniculate Arteries

Objective: To describe bypass to perigeniculate vessels for limb salvage. Design: Retrospective cohort study. Material and methods: Between 1995 and 2009, 47 bypass procedures to perigeniculate collateral arteries were performed in 46 patients (15 women, 31 men; median age, 68 years). All patients presented with critical ischaemia (tissue loss in 87.5%, rest pain in 12.5%). Mean ankle brachial index was 0.27 +/- 0.17. The site of distal anastomosis was the descending genicular artery (DGA) in 23 bypasses (1 bilateral) and the medial sural artery (MSA) in 24. Proximal anastomosis was to the external iliac artery in 2 cases, common femoral artery in 23 cases, superficial femoral artery in 8 cases, deep femoral artery in 8 cases, above-knee poplitaeal artery in 2 cases, and previous graft in 4 cases. Results: There were four deaths during the immediate postoperative period. Mean follow-up duration was 27 months. Ten patients required major amputation. Mean ankle brachial index post-operatively was 0.60 +/- 0.21. At 3 years, primary patency was 74.7 +/- 7%, secondary patency was 83.4 +/- 8%, and the limb salvage and survival rates were 73.5 +/- 7% and 77.4 +/- 7%, respectively. Conclusion: Bypass to perigeniculate arteries is a viable treatment option for critical limb ischaemia in selected patients. (C) 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.