Search results for " volunteers"
showing 10 items of 229 documents
Investigating prismatic adaptation effects in handgrip strength and in plantar pressure in healthy subjects.
2020
Abstract Background Prismatic Adaptation (PA) is a visuomotor procedure inducing a shift of the visual field that has been shown to modulate activation of a number of brain areas, in posterior (i.e. parietal cortex) and anterior regions (i.e. frontal cortex). This neuromodulation could be useful to study neural mechanisms associated with either postural measures such as the distribution of plantar pressure or to the generation of muscle strength. Indeed, plantar pressure distribution is associated to activation of high-level cognitive mechanisms taking place within the posterior regions of the brain dorsal stream, especially of the right hemisphere. Conversely, hand force mostly rely on sen…
Selective activation of shoulder, trunk, and arm muscles: A comparative analysis of different push-up variants
2015
Context The push-up is a widely used exercise for upper limb strengthening that can be performed with many variants. A comprehensive analysis of muscle activation during the ascendant phase (AP) and descendant phase (DP) in different variants could be useful for trainers and rehabilitators. Objective To obtain information on the effect of different push-up variants on the electromyography (EMG) of a large sample of upper limb muscles and to investigate the role of the trunk and abdomen muscles during the AP and DP. Design Cross-sectional study. Setting University laboratory. Patients or Other Participants Eight healthy, young volunteers without a history of upper extremity or spine injury.…
Microcentrifuge or Automated Hematological Analyzer to Assess Hematocrit in Exercise? Effect on Plasma Volume Loss Calculations
2016
The assessment of plasma volume loss (∆PV) induced by exercise can be estimated from changes in hematocrit (Htc) and hemoglobin (Hb), and it is essential when investigating the metabolic or biologic response to exercise of circulating biomarkers. We aimed to ascertain whether the estimation of ∆PV may differ when Hb and Htc are determined by automated hematological analyzer (AHA) versus manual methods. Twenty-five healthy male subjects performed a maximal running incremental exercise. Blood samples were taken before exercise, immediately after exercise, and after a 30-min recovery. Hb and Htc (Htc-AHA) were determined by an AHA. Htc was also determined by microcentrifugation (Htc-M). The ∆P…
Daily changes of individual gait patterns identified by means of support vector machines.
2016
Despite the common knowledge about the individual character of human gait patterns and about their non-repeatability, little is known about their stability, their interactions and their changes over time. Variations of gait patterns are typically described as random deviations around a stable mean curve derived from groups, which appear due to noise or experimental insufficiencies. The purpose of this study is to examine the nature of intrinsic inter-session variability in more detail by proving separable characteristics of gait patterns between individuals as well as within individuals in repeated measurement sessions. Eight healthy subjects performed 15 gait trials at a self-selected spee…
Effect of nighttime aircraft noise exposure on endothelial function and stress hormone release in healthy adults.
2013
Aims Aircraft noise disturbs sleep, and long-term exposure has been shown to be associated with increases in the prevalence of hypertension and an overall increased risk for myocardial infarction. The exact mechanisms responsible for these cardiovascular effects remain unclear. Methods and results We performed a blinded field study in 75 healthy volunteers (mean age 26 years), who were exposed at home, in random order, to one control pattern (no noise) and two different noise scenarios [30 or 60 aircraft noise events per night with an average maximum sound pressure level (SPL) of 60 dB(A)] for one night each. We performed polygraphy during each study night. Noise caused a worsening in sleep…
Limb Ischemic Conditioning Induces Oxidative Stress Followed by a Correlated Increase of HIF-1α in Healthy Volunteers.
2019
Background Local and remote ischemic preconditioning has been used as a protective intervention against ischemia/reperfusion (I/R) damage in several preclinical and clinical studies. However, its physiological mechanisms are not completely known. I/R increases the production of reactive oxygen species, which also serve as messengers for a variety of functions. Hypoxia-inducible factor 1 alpha (HIF-1α) is probably the most important transcription factor mediator of hypoxic signaling. Objective We hypothesized that limb ischemic conditioning (LIC) induces a local oxidative/nitrosative stress and a correlated increase of HIF-1α plasma levels. Methods An observational, prospective, and single-c…
Vitamin D, precocious acute myocardial infarction, and exceptional longevity
2015
Recent studies have reported low circulating levels of 25-hydroxyvitamin D (25(OH)D), the biologically active form of vitamin D, in patients with cardiovascular disease (CVD) [1], hypertension [2], carotid atherosclerosis [3], atrial fibrillation [4], and heart failure [5]. Moreover, vitamin D deficiency has been associated with all-cause mortality [6,7] and predicts adverse cardiac events in patients with established CVD [8] or after acute myocardial infarction (AMI) [9]. In turn, vitamin D supplementation improves the modulation of autonomic tone [10]. 4.638 JCR (2015) Q1, 24/124 Cardiac and cardiovascular systems UEM
Comparison of tactile sensitivity measured with a new digital esthesiometer (Beam Test) relative to Semmes–Weinstein monofilament analog esthesiometer
2019
The assessment of tactile sensitivity uses many tests, of which monofilaments are considered the best. The aim of this study was to develop a tactile sensitivity test, similar to the monofilament test, which eliminates the error risk related to manipulations by the observer, and to establish a correspondence scale. We studied 29 healthy subjects (18 women and 11 men) with a mean age of 27.8 years. The Semmes-Weinstein monofilament (SWM) analog esthesiometer and a digital beam esthesiometer (DBE) were used. We evaluated the tactile sensitivity threshold on the fingertip of each subject's dominant index using the SWM and the DBE. The DBE test consisted of applying the index against the tip of…
Echocardiographic reference ranges for normal left ventricular layer-specific strain: results from the EACVI NORRE study
2020
Abstract Aims To obtain the normal range for 2D echocardiographic (2DE) measurements of left ventricular (LV) layer-specific strain from a large group of healthy volunteers of both genders over a wide range of ages. Methods and results A total of 287 (109 men, mean age: 46 ± 14 years) healthy subjects were enrolled at 22 collaborating institutions of the EACVI Normal Reference Ranges for Echocardiography (NORRE) study. Layer-specific strain was analysed from the apical two-, three-, and four-chamber views using 2DE software. The lowest values of layer-specific strain calculated as ±1.96 standard deviations from the mean were −15.0% in men and −15.6% in women for epicardial strain, −16.8% …
Proteinuric effect of transcranial magnetic stimulation in healthy subjects and diabetic patients with stage 3-4 CKD
2013
BackgroundMany authors have investigated the numerous connections between the nervous system and kidneys, and recent literature has indicated that these similar systems are interconnected. Recent scientific works have shown that there is similarity between the cerebral cortex 'viscera representation' and the 'motor omunculus'. We studied the connection between the brain and kidney in vivo using repetitive transcranial magnetic stimulation (rTMS). Proteinuria and albuminuria were used as markers of renal response in patients with diabetes (DP) and in a group of healthy subjects (HSs) who received rTMS for 5 consecutive days.MethodsThe study population consists of the following four groups: G…