Browsing by Author "Delgado Bravo, Mauricio Antonio"

Now showing 1 - 7 of 7
  • Thumbnail Image
    Item
    Alterations in skeletal muscle morphology and mechanics in juvenile male Sprague Dawley rats exposed to a high-fat high-sucrose diet.
    (2023) Delgado Bravo, Mauricio Antonio; Hart, David A.; Reimer, Raylene A.; Herzog, Walter
    Although once a health concern largely considered in adults, the obesity epidemic is now prevalentin pediatric populations. While detrimental effects on skeletal muscle function have been seen inadulthood, the effects of obesity on skeletal muscle function in childhood is not clearly understood.The purpose of this study was to determine if the consumption of a high-fat high-sucrose (HFS) diet,starting in the post-weaning period, leads to changes in skeletal muscle morphology and mechanicsafter 14 weeks on the HFS diet. Eighteen 3-week-old male CD-Sprague Dawley rats were randomlyassigned to a HFS (C-HFS, n = 10) or standard chow diet (C-CHOW, n = 8). Outcome measures included: weekly energy intake, activity levels, oxygen consumption, body mass, body composition, metabolic profile, serum protein levels, and medial gastrocnemius gene expression, morphology, and mechanics. The main findings from this study were that C-HFS rats: (1) had a greater body mass and percent body fat than control rats; (2) showed early signs of metabolic syndrome; (3) demonstrated potential impairment in muscle remodeling; (4) produced lower relative muscle force; and (5) had a shift in the force–length relationship, indicating that the medial gastrocnemius had shorter muscle fiber lengths compared to those of C-CHOW rats. Based on the results of this study, we conclude that exposure to a HFS diet led to increased body mass, body fat percentage, and early signs of metabolic syndrome, resulting in functional deficits in MG of childhood rats.
  • Thumbnail Image
    Item
    Biomechanical analysis of expert anesthesiologists and novice residents performing a simulated central venous access procedure
    (2021) Villagrán Gutiérrez, Ignacio Andrés; Moenne Vargas, Cristóbal Matías; Aguilera Siviragol, Victoria Ignacia; Garcia, Vicente; Reyes, Jose Tomas; Rodriguez, Sebastian; Miranda Mendoza, Constanza; Altermatt, Fernando; Fuentes López, Eduardo; Delgado Bravo, Mauricio Antonio; Neyem, Andrés
    Background Central venous access (CVA) is a frequent procedure taught in medical residencies. However, since CVA is a high-risk procedure requiring a detailed teaching and learning process to ensure trainee proficiency, it is necessary to determine objective differences between the expert’s and the novice’s performance to guide novice practitioners during their training process. This study compares experts’ and novices’ biomechanical variables during a simulated CVA performance. Methods Seven experts and seven novices were part of this study. The participants’ motion data during a CVA simulation procedure was collected using the Vicon Motion System. The procedure was divided into four stages for analysis, and each hand’s speed, acceleration, and jerk were obtained. Also, the procedural time was analyzed. Descriptive analysis and multilevel linear models with random intercept and interaction were used to analyze group, hand, and stage differences. Results There were statistically significant differences between experts and novices regarding time, speed, acceleration, and jerk during a simulated CVA performance. These differences vary significantly by the procedure stage for right-hand acceleration and left-hand jerk. Conclusions Experts take less time to perform the CVA procedure, which is reflected in higher speed, acceleration, and jerk values. This difference varies according to the procedure’s stage, depending on the hand and variable studied, demonstrating that these variables could play an essential role in differentiating between experts and novices, and could be used when designing training strategies.
  • Thumbnail Image
    Item
    Correction to: Age‑related gait adaptations of ground reaction forces (Research on Biomedical Engineering, (2023), 10.1007/s42600-023-00315-6)
    (2023) Baptista, R.R.; Delgado Bravo, Mauricio Antonio; Heidner, G.S.; Ponce, Á.R.; Vieira, M.F.
    The original version of this paper was published with error. All Authors are mentioned under the same institution. The original article has been corrected. © 2023, The Author(s), under exclusive licence to The Brazilian Society of Biomedical Engineering.
  • Thumbnail Image
    Item
    Eating contexts determine the efficacy of nutrient warning labels to promote healthy food choices
    (Frontiers Media S.A., 2023) Caballero Vivanco, Sara; Moenne Vargas, Cristóbal Matías; Delgado Bravo, Mauricio Antonio; Luarte Rodríguez, Luis Nicolás; Jiménez, Yanireth; Galgani Fuentes, José Eduardo; Perez Leighton, Claudio
    Introduction: Unhealthy food choices increase the risk of obesity and its co-morbidities. Nutrition labels are a public health policy that aims to drive individuals toward healthier food choices. Chile has been an example of this policy, where mandatory nutrient warning labels (NWL) identify processed foods high in calories and critical nutrients. Eating contexts influence individual food choices, but whether eating contexts also influence how NWL alter the decision process and selection during food choice is unknown. Methods: In an online mouse-tracking study, participants prompted to health, typical, or unrestricted eating contexts were instructed to choose between pairs of foods in the presence or absence of NWL. Conflict during choices was analyzed using mouse paths and reaction times. Results: NWL increased conflict during unhealthy food choices and reduced conflict during healthy choices in all contexts. However, the probability that NWL reversed an unhealthy choice was 80% in a healthy, 37% in a typical, and 19% in an unrestricted context. A drift-diffusion model analysis showed the effects of NWL on choice were associated with an increased bias toward healthier foods in the healthy and typical but not in the unrestricted context. Discussion: These data suggest that the efficacy of NWL to drive healthy food choices increases in a healthy eating context, whereas NWL are less effective in typical or unrestricted eating contexts.
  • Thumbnail Image
    Item
    Medial Gastrocnemius Myotendinous Junction Displacement and Plantar-Flexion Strength in Patients Treated With Immediate Rehabilitation After Achilles Tendon Repair
    (2016) De la Fuente, Carlos; Pena Y. Lillo, R.; Ramirez, R.; Ortega, P.; Delgado Bravo, Mauricio Antonio; Álvarez Ruf, Joel Esteban; Carreno, G.
  • Thumbnail Image
    Item
    Muscle Activity and Aerodynamic Voice Changes at Different Body Postures: A Pilot Study
    (Elsevier Inc., 2022) Castillo Allendes, Adrián; Delgado Bravo, Mauricio Antonio; Reyes Ponce, Alvaro; Hunter, Eric J.
    © 2022 The Voice FoundationObjective: Body posture is a commonly discussed component of voice training and therapy. However, body postures, postural changes, related posturing muscle monitoring, and the potential changes in voice production (eg, glottal aerodynamic changes, acoustic differences) have been inconsistently described in the literature, leaving room for free interpretation and possible misunderstandings. The primary purpose of this pilot study was to compare the magnitude of electromyographical activation of muscles involved in phonation-breathing functions and their changes due to four standardized body postures in experienced singers. Secondly, to identify which body posture produces greater changes in aerodynamic parameters, vocal pitch, and loudness. Methods: Eight healthy adults with experience in singing voice performed a vocal task during different body postures commonly used in both voice training and therapy. A 3D-capture system was used to control and quantify the alignment of each posture. During the performances, surface electromyography (sEMG) was used to measure the muscular activity involved in the breathing/phonation and posture processes. A nonparametric Kruskal-Wallis test was used to compare the sEMG activity of phonatory muscles and aerodynamic voice variables between postures. Results: Our study did not reveal significant differences in sEMG activity, aerodynamic parameters, vocal pitch, and loudness among body postures during vocal task productions. However, the vocal pitch (in semitones) revealed significant differences in the unstable surface when compared to the upright posture, modified upright, and leaning postures. Conclusion: The body postures selected did not generate voice aerodynamic modifications of the voice nor in the levels of activation of muscles involved in the phonation-breathing process in individuals with experience in singing voice. Modifications of body posture as a tool for voice therapy should be further investigated, considering the population with voice problems and no voice training experience.
  • Thumbnail Image
    Item
    Percepción de los estudiantes de kinesiología sobre la incorporación de la metodología b-learning y uso de dispositivos móviles en el curso de análisis del movimiento
    (2019) Delgado Bravo, Mauricio Antonio; Cerda Vega, Enrique; Villagran Gutiérrez, Ignacio Andrés; Fuentes López, Eduardo
    Introducción: el aumento del número de estudiantes en carreras de la salud hace necesario incluir nuevas metodologías de enseñanza-aprendizaje. La literatura avala el uso de las tecnologías de la información y comunicación (TICs) y el b-learning como recursos para abordar esta problemática. El propósito fue evaluar la percepción de los estudiantes universitarios de la carrera de kinesiología sobre la incorporación de TICs y b-learning en el curso Análisis del Movimiento. Material y Método: se aplicó un cuestionario a 94 estudiantes. Se determinó evidencia de validez de constructo a través de análisis confirmatorio de factores y confiabilidad mediante Alpha de Cronbach. Se estimó la mediana (Q1-Q3) de cada dimensión, determinando posibles diferencias mediante la prueba de Kruskal-Wallis. Resultados: se definió una encuesta con 5 dimensiones y 27 ítems. Los enunciados cargaron en las 5 dimensiones. El coeficiente de Alpha de Cronbach fue de α=0,83. Los resultados según la Mediana (Q1-Q3) por dimensión fueron: Percepción General de la Metodología 4,83 (4,67-5), Percepción de los materiales utilizados 4,75 (4,5-5), Percepción del Autoaprendizaje 4,09 (3,82-4,27), Interacción con los docentes y compañeros 4,75 (4,25-5), Evaluación 5 (4,67-5) y la nota global fue de 6 (6-7). Discusión: el cuestionario posee adecuada evidencia de validez y confiabilidad, hubo diferencias estadísticamente significativas entre dimensiones, especialmente en Percepción del Autoaprendizaje. A Los estudiantes valoran positivamente la organización en los procesos de innovación en metodologías de enseñanza y evaluación, el uso de sistemas digitales como facilitadores de su aprendizaje y la oportunidad de aprendizaje autónomo.