A NEW METHOD FOR EVALUATION OF THE CARRYING ANGLE IN-VIVO SET UP

The "carrying angle" is defined as the angle formed by the long axis of the humerus and the long axis of the ulna(1.2J. This angle was measured in-vitro by several methodsl1j but few authors accomplished this measurements in vivo [2J probably due to the difficulties related to the identification of repere points. The goal of this work was to define an easy, fast and accurate new method for evaluation of the carrying angle in an in-vivo set up usable in rehabilitation and sport fields. In this work we present the method, analyse its repeatability and we compare the results with measures performed using a goniometer

A PRELIMINARY STUDY TO MODEL CARRYING ANGLE VARIATIONS DURING FLEXION-EXTENSION OF THE ELBOW

The aim of this work was to identify an accurate method to evaluate the variability of the carrying angle during the flexion extension of the elbow and to define a mathematical description of this movement applicable in sport and rehabilitation field. In order to develop this objective, we marked the arm and the forearm by six reflective markers of six healthy subjects performing the flexion extension movement and acquired the coordinates using six infrared cameras (VICON Motion System). Five repeated measures were performed for each subject in order to verify the reliability of the measures. Our results demonstrated that this movement can be easily modelled as a linear variation of the carrying angle in function of the flexion angle. The reliability between repeated measures was high and adopting a linear fit the accuracy was more than 94% in all cases. This is the first study to compute the flexion-extension movement by a carrying angle evaluation

EQUATION REGRESSION MODEL FOR THE 50 M FREESTYLE PERFORMANCE IN ELITE MASTER SWIMMERS

This study was conducted during the 10th World Masters Championships, held in Riccione, Italy, June 3-11, 2004. The aim was to investigate, in male and female elite master swimmers, the relationships between performance time and age, anthropometric characteristics (weight, stature, arm and forearm lengths and forearm volume) and muscle strength (hand grip). Performance times were recorded during 50 m freestyle events. Anthropometric values and hand grip were collected the same day the competition in a field laboratory organised beside the swimming pool. For this study we considered twenty eight volunteers: 15 men aged 42-81 years and 13 women aged 4173 years. Firstly, the anthropometrical characteristics. the hand grip strength and the performance time were used for a simple correlation analysis. Subsequently a multiple regression analysis was carried out to create a swimming time prediction model for the 50 freestyle performances. It revealed that in 50 m freestyle women race, age, weight and strength explained about 97% of the variance in performance. This study provided novel information which could be useful in designing training programs, optimizing swimmer's resources or capabilities

INFLUENCE OF AGE AND HAND GRIP STRENGTH ON FREESTYLE PERFORMANCES IN MASTER SWIMMERS

The aim of our work was to examine whether age and hand grip strength are correlated with 50m, 100m, 200m, 400m, 800m swimming performance times in Master swimmers and how correlation varies considering short, middle or long distances. The main finding of this work was that hand grip strength and age correlated significantly at each distance. Hand grip strength showed a relevant influence on performance time and explained 52% of variance of performance time in 50m race freestyle and only 15% in 800m race. Increasing age was a disadvantageous factor for performance time, and explained 45% of variance of performance time in 800m race freestyle and only 20% in 50 m race

Large Proteins Have a Great Tendency to Aggregate but a Low Propensity to Form Amyloid Fibrils

The assembly of soluble proteins into ordered fibrillar aggregates with cross-β structure is an essential event of many human diseases. The polypeptides undergoing aggregation are generally small in size. To explore if the small size is a primary determinant for the formation of amyloids under pathological conditions we have created two databases of proteins, forming amyloid-related and non-amyloid deposits in human diseases, respectively. The size distributions of the two protein populations are well separated, with the systems forming non-amyloid deposits appearing significantly larger. We have then investigated the propensity of the 486-residue hexokinase-B from Saccharomyces cerevisiae (YHKB) to form amyloid-like fibrils in vitro. This size is intermediate between the size distributions of amyloid and non-amyloid forming proteins. Aggregation was induced under conditions known to be most effective for amyloid formation by normally globular proteins: (i) low pH with salts, (ii) pH 5.5 with trifluoroethanol. In both situations YHKB aggregated very rapidly into species with significant β-sheet structure, as detected using circular dichroism and X-ray diffraction, but a weak Thioflavin T and Congo red binding. Moreover, atomic force microscopy indicated a morphology distinct from typical amyloid fibrils. Both types of aggregates were cytotoxic to human neuroblastoma cells, as indicated by the MTT assay. This analysis indicates that large proteins have a high tendency to form toxic aggregates, but low propensity to form regular amyloid in vivo and that such a behavior is intrinsically determined by the size of the protein, as suggested by the in vitro analysis of our sample protein

Coordination in climbing: effect of skill, practice and constraints manipulation

BACKGROUND: Climbing is a physical activity and sport involving many subdisciplines. Minimization of prolonged pauses, use of a relatively simple path through a route and smooth transitions between movements broadly define skilled coordination in climbing. OBJECTIVES: To provide an overview of the constraints on skilled coordination in climbing and to explore future directions in this emerging field. METHODS: A systematic literature review was conducted in 2014 and retrieved studies reporting perceptual and movement data during climbing tasks. To be eligible for the qualitative synthesis, studies were required to report perceptual or movement data during climbing tasks graded for difficulty. RESULTS: Qualitative synthesis of 42 studies was carried out, showing that skilled coordination in climbing is underpinned by superior perception of climbing opportunities; optimization of spatial-temporal features pertaining to body-to-wall coordination, the climb trajectory and hand-to-hold surface contact; and minimization of exploratory behaviour. Improvements in skilled coordination due to practice are related to task novelty and the difficulty of the climbing route relative to the individual's ability level. CONCLUSION: Perceptual and motor adaptations that improve skilled coordination are highly significant for improving the climbing ability level. Elite climbers exhibit advantages in detection and use of climbing opportunities when visually inspecting a route from the ground and when physically moving though a route. However, the need to provide clear guidelines on how to improve climbing skill arises from uncertainties regarding the impacts of different practice interventions on learning and transfer

HIV-1 matrix protein p17 misfolding forms toxic amyloidogenic assemblies that induce neurocognitive disorders

© 2017 The Author(s). Human immunodeficiency virus type-1 (HIV-1)-Associated neurocognitive disorder (HAND) remains an important neurological manifestation that adversely affects a patient's quality of life. HIV-1 matrix protein p17 (p17) has been detected in autoptic brain tissue of HAND individuals who presented early with severe AIDS encephalopathy. We hypothesised that the ability of p17 to misfold may result in the generation of toxic assemblies in the brain and may be relevant for HAND pathogenesis. A multidisciplinary integrated approach has been applied to determine the ability of p17 to form soluble amyloidogenic assemblies in vitro. To provide new information into the potential pathogenic role of soluble p17 species in HAND, their toxicological capability was evaluated in vivo. In C. elegans, capable of recognising toxic assemblies of amyloidogenic proteins, p17 induces a specific toxic effect which can be counteracted by tetracyclines, drugs able to hinder the formation of large oligomers and consequently amyloid fibrils. The intrahippocampal injection of p17 in mice reduces their cognitive function and induces behavioral deficiencies. These findings offer a new way of thinking about the possible cause of neurodegeneration in HIV-1-seropositive patients, which engages the ability of p17 to form soluble toxic assemblies