Body center of mass displacements during walking with low- and high-heeled shoes

Walking is a natural activity that is very often performed wearing shoes. Among many other kinds of footwear, high-heeled shoes induce increased ankle plantar flexion, greater knee flexion, anterior pelvic tilt, and trunk extension [1]. The modifications in the arrangement of body segments cause an altered position of the body centre of mass (CoM). In the current study, we quantitatively compared the 3D displacement of CoM during flat-heeled and high-heeled gait. Eleven volunteer women (mean age, 24 years) walked wearing either low-heeled and high-heeled shoes (minimum height, 70 mm). On each subject, the 3D coordinates of 14 body landmarks were recorded by an optoelectronic motion analyzer. The body was segmented in 10 independent masses: head, torso, two upper arms and two lower arms (upper body); two upper legs and two lower legs (lower body). Using mean anthropometric data, the whole body CoM was computed, as well as its superior (uCoM) and inferior (iCoM) components [2]. The body CoM was evaluated during normalized stride cycles. High-heeled gait, compared to flat-heeled gait, had a significantly lower CoM at Right heel strike (p=0.024) and Left heel strike (p=0.030). The same findings were also observed for uCoM and iCoM. No significant differences were found at Right toe off. In addition, a significant forward displacement of the iCoM in high-heeled gait was observed at each of the three stages (R heel strike, p=0.017; L heel strike, p=0.034; R toe off, p=0.003). Similar results were found for the whole CoM (p=0.024, p=0.038, p=0.004). The uCoM in high-heeled gait, instead, was significantly more anterior than in flat-heeled gait only at R toe off (p=0.024). Our findings confirmed that wearing high-heeled shoes significantly alters the normal displacement of both components of the human CoM

Morphological and functional facial asymmetry in patients with mild temporomandibular disorders: a pilot study

Facial asymmetry is normal in humans[1]. Authors indicated that facial asymmetry could influence the shape and function of the temporomandibular joints and vice versa[2]. In this study we collected preliminary reference values for facial asymmetry in adults with temporomandibular disorders (TMD), compared to a control group, using a 3D stereophotogrammetric imaging system and electromyographic (EMG) indices. Forty subjects (22 TMD; 18 control; paired for age: 21±2y) were recruited. Five linear measurements for each hemiface and asymmetry index (AI%) were computed from stereophotogrammetric scans. Standardized EMG indices for masseter and temporal muscles were obtained during clenching and gum chewing. Means of control and TMD groups were compared by t-test. For both groups, the AI for all linear measurements ranged from -10% to +10%; there was a great variability, especially for TMD group, who showed the higher values. For EMG indices, TMD group demonstrated a tendency to a more asymmetric muscular recruitment in static activities (masseter & temporal symmetry, C 87.5±1.76%; TMD 84.6±6.2%; p=0.06) and reduced symmetry during gum chewing (C 67.1± 20.9%; TMD 55.0±18.1%; p=0.06). The presence of higher asymmetry for stereophotogrammetry and EMG analyses, as well as the presence of alterations of masticatory function for the TMD group, suggest that this relationship should be further investigated. An analysis with a larger sample and with more severe TMD patients, together with a longitudinal study, is required to understand these possible relationships between morphology and function

Maximum voluntary clenching and unilateral chewing in patients with mild-moderate TMD

Temporomandibular disorders (TMD) consist of a number of clinical problems that involve the masticatory muscles, the temporomandibular joint and associated structures. The aim of the study was to quantitatively compare electromyographic (EMG) parameters of patients with mild-moderate TMD and healthy subjects. Twenty patients with mild-moderate TMD (5 men, 15 women, 22–56 y) and 19 healthy subjects (9 men, 10 women, 21–49 y) were analyzed. sEMG of the left and right masseter and temporalis anterior muscles was recorded using a wireless device (TMJoint, BTS, Italy). Each subject performed a 5 s-maximum voluntary contraction (MVC) with the teeth in intercuspal position (CLENCH), and one with two 10 mm-thick cotton rolls positioned on the mandibular second premolars/first molars (COT). EMG activity was further recorded during unilateral, right and left, gum chewing. EMG potentials of both MVC and chewing were standardized as percentages of the potentials obtained during COT recording [1]. During MVC, EMG activities were less symmetric and had a larger torque component in TMD patients than in healthy subjects (muscular asymmetry: 10.4±9.1% vs 4.4±4.2%, Student’s t-test, p=0.013; torque: 9.8±10.9% vs 4.4±4.0%, p=0.047). During chewing, all healthy subjects had a good coordination between masseter and temporalis contractions, with a prevalent activity of the working-side muscles. Among TMD patients, instead, 9 subjects performed at least one of their unilateral chewing tests with an altered muscular coordination. EMG activity of TMD patients was less coordinated than that of healthy subjects, with a larger variability between chewing cycles (Hotelling’s ellipse area: 2275±2734% vs 1010±845%, Student’s t-test, p=0.061). sEMG analysis could be a useful tool to detect functionally altered stomatognathic muscular coordination. Dote ricerca: FSE, Regione Lombardi

Facial movements during verbal and not verbal activities: an optoelectronic 3D study

Functional impairments of facial movements alter the quality of life, and their quantitative analysis is a key step in the description and grading of facial function and dysfunction. In this investigation we assessed the symmetry of lip movements in verbal and non verbal movements in healthy subjects. Fifteen healthy young adults (aged 24.7±4.6 y) were analysed using a 3D motion analyzer (SMART-E, BTS, Italy). All subjects had a clinically normal facial function. For each subject, 11 soft tissue landmarks were identified by a set of 5-mm round reflective markers: n, nasion; ft, right and left frontotemporale; ng, right and left naso-genian; cph, right and left crista philtri; ch, right and left cheilion; li, right and left lower lip midpoints. Each subject performed five standardized, maximum labial animations from rest: open mouth smile (OS); closed mouth smile (CS); spontaneous smile (SS); lip pursing (LP); vowels pronunciation. Ten repetitions of each expression were recorded without modifications of the marker positions. The total 3D mobility of right and left sides (unit: mm) was computed during smile animations (OS: 42±11.1 vs 44.1±10.8; CS: 30.5±11.4 vs 33.1±12.3; SS: 38.8±13.7 vs 39.5±12.7), lip purse (35.1±5.8 vs 34.9±7.1) and vowels pronunciation (a: 33.8±9.5 vs 33.4±11.2; e: 21.4±8.1 vs 21±9.4; i: 15.4±5.2 vs 15.4±5.7; o: 23.2±7.6 vs 22.2±6.6; u: 20.8±6.5 vs 18.8±6.2). The movements were symmetric (no significant differences were found, Student’s t-paired test, p>0.05). Additionally, the asymmetry indices of labial landmark displacement [1] were not significantly different from 0 in both not-verbal (OS: 2.9%; CS: 4.3%; SS: 3.5%; LP: 0.7%) and verbal (a: 1.2%; e: 1.7%; i: 0.5%; o: 1.7%; u: 5.2%) activities. In conclusion, in healthy young adults standardized labial movements were performed with similar mobility between right and left sides. Data will be used for the quantitative assessment of the impairments of patients with facial lesions

Impacto do ensino síncrono remoto durante a Pandemia em acadêmicos de medicina : Impact of remote synchronous teaching during the pandemic on medical students

O vírus Sars-Cov-19 assolou o mundo e impôs novos hábitos de vida a todos e neste período o sistema educacional adaptou uma nova maneira de ensino síncrono remoto em plataformas online. Buscou-se fazer uma pesquisa exploratória referente aos efeitos do isolamento social em acadêmicos de medicina de abordagem quantitativa, realizada com 179 participantes. A coleta de dados ocorreu no quarto trimestre de 2020 com a aplicação de um questionário semiestruturado em plataformas sociais. Como resultados, obteve-se que o isolamento social foi dos protagonistas na interferência do aprendizado do académico devido a influência negativa na saúde mental no indivíduo, interferindo diretamente questões financeiras, de aprendizado e bem-estar. Todos os participantes demonstraram que em algum momento tiveram contato com os problemas da pesquisa. Nesse contexto de um momento desafiador, o ensino demonstra-se insuficiente e traz diversos agravos a saúde mental do discente

Common variants at ABCA7, MS4A6A/MS4A4E, EPHA1, CD33 and CD2AP are associated with Alzheimer's disease

We sought to identify new susceptibility loci for Alzheimer's disease through a staged association study (GERAD+) and by testing suggestive loci reported by the Alzheimer's Disease Genetic Consortium (ADGC) in a companion paper. We undertook a combined analysis of four genome-wide association datasets (stage 1) and identified ten newly associated variants with P ≤ 1 × 10−5. We tested these variants for association in an independent sample (stage 2). Three SNPs at two loci replicated and showed evidence for association in a further sample (stage 3). Meta-analyses of all data provided compelling evidence that ABCA7 (rs3764650, meta P = 4.5 × 10−17; including ADGC data, meta P = 5.0 × 10−21) and the MS4A gene cluster (rs610932, meta P = 1.8 × 10−14; including ADGC data, meta P = 1.2 × 10−16) are new Alzheimer's disease susceptibility loci. We also found independent evidence for association for three loci reported by the ADGC, which, when combined, showed genome-wide significance: CD2AP (GERAD+, P = 8.0 × 10−4; including ADGC data, meta P = 8.6 × 10−9), CD33 (GERAD+, P = 2.2 × 10−4; including ADGC data, meta P = 1.6 × 10−9) and EPHA1 (GERAD+, P = 3.4 × 10−4; including ADGC data, meta P = 6.0 × 10−10)

Effect of leg dominance on the center-of-mass kinematics during an inside-of-the-foot kick in amateur soccer players

Soccer kicking kinematics has received wide interest in literature. However, while the instep-kick has been broadly studied, only few researchers investigated the inside-of-the-foot kick, which is one of the most frequently performed techniques during games. In particular, little knowledge is available about differences in kinematics when kicking with the preferred and non-preferred leg. A motion analysis system recorded the three-dimensional coordinates of reflective markers placed upon the body of nine amateur soccer players (23.0 ± 2.1 years, BMI 22.2 ± 2.6 kg/m2), who performed 30 pass-kicks each, 15 with the preferred and 15 with the non-preferred leg. We investigated skill kinematics while maintaining a perspective on the complete picture of movement, looking for laterality related differences. The main focus was laid on: anatomical angles, contribution of upper limbs in kick biomechanics, kinematics of the body Center of Mass (CoM), which describes the whole body movement and is related to balance and stability. When kicking with the preferred leg, CoM displacement during the ground-support phase was 13% higher (p<0.001), normalized CoM height was 1.3% lower (p<0.001) and CoM velocity 10% higher (p<0.01); foot and shank velocities were about 5% higher (p<0.01); arms were more abducted (p<0.01); shoulders were rotated more towards the target (p<0.01, 6° mean orientation difference). We concluded that differences in motor control between preferred and non-preferred leg kicks exist, particularly in the movement velocity and upper body kinematics. Coaches can use these results to provide effective instructions to players in the learning process, moving their focus on kicking speed and upper body behavior

Short-term and long-term impact of moderate vs vigorous integrated weight-loss programs on physiological parameters

Few studies have examined the impact of various intensities of exercise on physiological parameters during weight loss program. PURPOSE The aim of this study was to compare the short-term and long-term results of an integrated weight-loss program (BWR) on selected physiological parameters considering moderate (MI) or vigorous (HI) physical activity (PA), and the maintenance in the term of their positive effects. METHODS 24 young severely obese subjects (age, 26,38\ub14,72 yr; BMI, 42,62\ub15,28 kg/m2), divided into 2 homogeneous groups, followed a 3 weeks BWR composed by: an energy intake reduction, psychological and nutritional counselling and a customized PA program (5 training sessions/week). PA program intensity of both groups ranged between 50 and 70% of VO2max for cardiovascular exercises and between 40 and 70% of 1RM for strength exercises. Volume was the same for both groups: 30 min for cardiovascular exercises and 1x10 for strength exercises. Before (pre) and after (post) the intervention period and one year later (fu) a sub-maximal indirect test to estimate VO2max and a maximal indirect test to calculate 1RM were carried out. RESULTS VO2max significantly increased for both groups (p<0,05) after BWR; further increase occurred for both groups after 1 year, p=ns (VO2max: MI, pre 22,7\ub17,2 post 25,5\ub16,1 fu 27,3\ub17,6 ml/kg/min; HI, pre 25,6\ub18,8 post 28,4\ub110,4 fu 30,4\ub110,8 ml/kg/min). At short-term 1RM significantly increased for both groups ( 06%, Leg press MI +37.1, HI +44.7; Chest press MI +39.6, HI +34.3; Vertical traction MI +31.9, HI +41; p<0,001), followed by a decrease after one year ( 06%, Leg press MI -6.8, HI -23.6; Chest press MI -6.6, HI -19.6; Vertical traction MI -9.6, HI -12.6), which resulted to be statistically significant only for HI (p<0,01). No significant differences were detected between groups. CONCLUSION This study shows that the intensity of exercise (MI or HI) doesn t affect the magnitude of change in cardiorespiratory fitness and muscular strength. These results underline the importance of a PA to maintain elevated values of physical fitness over time. In fact, more than 60 min per week of recreation or work requiring modest PA, reported by the subjects, allow to enhance only VO2max, while maximal strength decreased because no specific training session was performed