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1.
Am J Otolaryngol ; 45(1): 104078, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37806280

RESUMEN

This article describes the first recorded case of intratemporal neurofibroma in an infant. A literature review of all other existing cases of intratemporal neurofibroma is performed, finding that the majority of cases involve multiple segments and can be found in the mastoid segment most often. Most common symptoms described included facial paralysis, otalgia, and conductive hearing loss, respectively.


Asunto(s)
Enfermedades del Nervio Facial , Parálisis Facial , Neurofibroma , Lactante , Humanos , Parálisis Facial/etiología , Nervio Facial , Enfermedades del Nervio Facial/diagnóstico , Enfermedades del Nervio Facial/etiología , Enfermedades del Nervio Facial/cirugía , Neurofibroma/complicaciones , Neurofibroma/diagnóstico , Neurofibroma/cirugía , Apófisis Mastoides , Hueso Temporal
2.
Am J Otolaryngol ; 45(2): 104134, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38103487

RESUMEN

PURPOSE: To explore anatomic predictors of mortality from gunshot wounds involving the temporal bone. METHODS: A retrospective search of radiology reports was performed for all patients with CT reports suggestive of gunshot wounds (GSW) to the TB (2000-2020). All cases were reviewed by the senior author to confirm injury to the temporal bone. Detailed demographic and radiographic data were collected. MAIN FINDINGS: A total of 120 patients met inclusion criteria. The majority of patients were male (n = 101) and the average age was 32.9. The squamosa was the most commonly involved subsite (n = 90), followed by the mastoid (n = 43). Squamosal entry site had the highest associated mortality (89.7 %). For those with known disposition, 65.8 % (79 of 120) expired on the same hospital admission. Inpatient otolaryngology consultation was noted in 18.3 % (n = 22) of patients, with poor outpatient follow-up. CONCLUSIONS: This series represents the largest survey of GSW to the temporal bone to date. Although associated mortality is high and outpatient follow-up poor, otolaryngologists should be aware of associated morbidities to facilitate both inpatient and subsequent outpatient management.


Asunto(s)
Heridas por Arma de Fuego , Humanos , Masculino , Femenino , Adulto , Estudios Retrospectivos , Centros Traumatológicos , Hospitalización , Hueso Temporal/diagnóstico por imagen
3.
Plant J ; 111(3): 713-730, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35644998

RESUMEN

As sessile organisms, plants must adapt their physiology and developmental processes to cope with challenging environmental circumstances, such as the ongoing elevation in atmospheric carbon dioxide (CO2 ) levels. Nicotinamide adenine dinucleotide (NAD+ ) is a cornerstone of plant metabolism and plays an essential role in redox homeostasis. Given that plants impaired in NAD metabolism and transport often display growth defects, low seed production and disturbed stomatal development/movement, we hypothesized that subcellular NAD distribution could be a candidate for plants to exploit the effects of CO2 fertilization. We report that an efficient subcellular NAD+ distribution is required for the fecundity-promoting effects of elevated CO2 levels. Plants with reduced expression of either mitochondrial (NDT1 or NDT2) or peroxisomal (PXN) NAD+ transporter genes grown under elevated CO2 exhibited reduced total leaf area compared with the wild-type while PXN mutants also displayed reduced leaf number. NDT2 and PXN lines grown under elevated CO2 conditions displayed reduced rosette dry weight and lower photosynthetic rates coupled with reduced stomatal conductance. Interestingly, high CO2 doubled seed production and seed weight in the wild-type, whereas the mutants were less responsive to increases in CO2 levels during reproduction, producing far fewer seeds than the wild-type under both CO2 conditions. These data highlight the importance of mitochondrial and peroxisomal NAD+ uptake mediated by distinct NAD transporter proteins to modulate photosynthesis and seed production under high CO2 levels.


Asunto(s)
Dióxido de Carbono , NAD , Dióxido de Carbono/metabolismo , NAD/metabolismo , Fotosíntesis/fisiología , Hojas de la Planta/metabolismo , Semillas/metabolismo
4.
Eur J Neurosci ; 57(12): 2174-2186, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37161490

RESUMEN

Perturbation-based balance training (PBT) exposes individuals to a series of sudden upright balance perturbations to improve their reactive postural responses. In this study, we aimed to evaluate the effect of a short PBT program on body balance recovery following a perturbation in individuals with freezing of gait due to Parkinson's disease. Volunteers (mean age = 64 years, SD = 10.6) were pseudorandomly assigned either to a PBT (n = 9) or to a resistance training (RT, n = 10) group. PBT was implemented through balance perturbations varying in the kind, direction, side and magnitude of support base displacements. Both groups exercised with progressive difficulty/load activities twice a week for 4 weeks. Specific gains and generalization to dual-tasking and faster-than-trained support base displacements were evaluated 24 h after the end of the training, and retention was evaluated after 30 days of no training. Results showed that, compared with RT, PBT led to more stable postural responses in the 30-day retention evaluation, as indicated by decreased CoP displacement, velocity and time to direction reversal and reduced numbers of near-falls. We found no transfer either to a dual task or to a higher perturbation velocity. In conclusion, a training program based on diverse unpredictable balance perturbations improved the stability of reactive postural responses to those perturbations suffered during the training, without generalization to more challenging tasks.


Asunto(s)
Trastornos Neurológicos de la Marcha , Enfermedad de Parkinson , Humanos , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/terapia , Trastornos Neurológicos de la Marcha/etiología , Trastornos Neurológicos de la Marcha/terapia , Equilibrio Postural/fisiología , Accidentes por Caídas , Marcha/fisiología
5.
Am J Otolaryngol ; 44(2): 103729, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36495649

RESUMEN

PURPOSE: Although uncommon, vascular injury can be seen in patients with lateral skull base fractures (LSBF). However, little is known about this potentially life-threatening comorbidity. The objective of this study is to better characterize the vascular injuries associated with temporal and lateral sphenoid bone fractures. BASIC PROCEDURES: Retrospective review of all patients with computed tomography angiography (CTA) performed specifically to evaluate for vascular injury following LSBF. In addition to patient demographics (age, gender, race), the mechanism of injury, the location of fracture(s), and the nature of vascular injury diagnosed by CTA was recorded. Two-way ANOVA was performed to determine if any variables were predictive of vascular injury. MAIN FINDINGS: From 2011 to 2021, 143 patients with 333 subsite fractures met inclusion criteria. Of all patients, 46 (32.2 %) had CTA evidence of at least one vascular injury, the most common type being venous thrombosis/filling defect (41.7 %). Evidence of vascular injury was unclear in 14 patients (9.8 %). Fractures most associated with vascular injury ranged from 0.7 % (otic capsule fractures) to 26.7 % (mastoid, lateral sphenoid fractures). Risk of vascular injury was no different between patients with single vs multiple fractures. There were no fracture locations that could reliably predict specific vascular injury. CONCLUSIONS: Over 40 % of all CTAs ordered following LSBF identified were suspicious for associated vascular injury. Yet fracture location and number cannot reliably predict vascular injury. Until such determinants can be better identified, clinicians should have a low threshold to obtain CTA to rule out associated vascular injury.


Asunto(s)
Traumatismos de las Arterias Carótidas , Base del Cráneo , Lesiones del Sistema Vascular , Estudios Retrospectivos , Lesiones del Sistema Vascular/diagnóstico por imagen , Base del Cráneo/lesiones , Arteria Carótida Interna/diagnóstico por imagen , Angiografía por Tomografía Computarizada , Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano
6.
J Sports Sci ; 41(7): 668-676, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37409691

RESUMEN

The penalty kick is a crucial opportunity to score and determine the outcome of a soccer match or championship. Anticipating the direction of the ball is key for goalkeepers to enhance their defensive capabilities, considering the ball's swift travel time. However, it remains unclear which kinematic cues from the kicker can predict the ball's direction. This study aimed to identify the variables that predict the ball's direction during a soccer penalty kick. Twenty U19 soccer players executed penalty kicks towards four targets positioned in the goal, while kinematic analysis was conducted using a 3D motion analysis system. Logistic regression analysis revealed that trunk rotation in the transverse plane (towards the goal - left; or slightly to the right - right) served as the primary predictor of the ball's horizontal direction at 250 and 150 ms before the kicking foot made contact. Additionally, the height of the kicking foot in the sagittal plane solely predicted the vertical direction at the moment of contact. This information, encompassing trunk rotation and kicking foot height, can be employed in perceptual training to enhance decision-making and the implementation of feints during penalty kicks.


Asunto(s)
Fútbol , Humanos , Fenómenos Biomecánicos , Señales (Psicología) , Pie , Extremidad Inferior
7.
Sensors (Basel) ; 23(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36679413

RESUMEN

Texture mapping can be defined as the colorization of a 3D mesh using one or multiple images. In the case of multiple images, this process often results in textured meshes with unappealing visual artifacts, known as texture seams, caused by the lack of color similarity between the images. The main goal of this work is to create textured meshes free of texture seams by color correcting all the images used. We propose a novel color-correction approach, called sequential pairwise color correction, capable of color correcting multiple images from the same scene, using a pairwise-based method. This approach consists of sequentially color correcting each image of the set with respect to a reference image, following color-correction paths computed from a weighted graph. The color-correction algorithm is integrated with a texture-mapping pipeline that receives uncorrected images, a 3D mesh, and point clouds as inputs, producing color-corrected images and a textured mesh as outputs. Results show that the proposed approach outperforms several state-of-the-art color-correction algorithms, both in qualitative and quantitative evaluations. The approach eliminates most texture seams, significantly increasing the visual quality of the textured meshes.


Asunto(s)
Algoritmos , Artefactos , Motivación , Color
8.
Geriatr Nurs ; 54: 60-65, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37703691

RESUMEN

OBJECTIVE: The objective of this study was to evaluate the effects of 12 weeks of resistance training (RT) with progressive intensity on factors associated with sarcopenia in older individuals. METHODS: A cross-sectional study was conducted with 74 participants (64.27 ± 7.06-y-old) who were divided into a control group (n = 37) and an intervention group (n = 37). The intervention group underwent 12 weeks of RT three times a week, with an initial training of 60% and final training of 85% of one-repetition maximum (1RM). Both groups were evaluated before and after the 12-week training period to assess improvements in strength and physical performance. RESULTS: The intervention group showed an increase in physical performance, as evidenced by a reduction in the time to perform the Timed Up and Go (TUG) test (p < 0.01) and the Five Times Sit to Stand Test (p < 0.01). Furthermore, the RT proved to be efficient for increasing hand grip and overall muscular strength, as confirmed through the 1RM test. However, the muscle mass index (MMI) and walking speed did not show any significant alterations in both groups. CONCLUSIONS: In conclusion, 12 weeks of RT with progressive intensity has a positive effect on the diagnostic parameters of sarcopenia, leading to improvements in physical performance and muscular strength while maintaining the MMI.


Asunto(s)
Entrenamiento de Fuerza , Sarcopenia , Humanos , Anciano , Sarcopenia/diagnóstico , Fuerza de la Mano/fisiología , Estudios Transversales , Fuerza Muscular/fisiología
9.
Eur J Appl Physiol ; 122(8): 1915-1928, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35612684

RESUMEN

PURPOSE: Caffeine improves cycling time trial (TT) performance; however, it is unknown whether caffeine is ergogenic when competing against other riders. The aim of this study was to investigate whether caffeine improves performance during a 4-km cycling TT when riding against a virtual opponent, and whether it is associated with increased muscle activation and at the expense of greater end-exercise central and peripheral fatigue. METHODS: Using a randomized, crossover, and double-blind design, eleven well-trained cyclists completed a 4-km cycling TT alone without supplementation (CON), or against a virtual opponent after ingestion of placebo (OP-PLA) or caffeine (5 mg.kg-1, OP-CAF). Central and peripheral fatigue were quantified via the pre- to post-exercise decrease in voluntary activation and potentiated twitch force, respectively. Muscle activation was continually measured during the trial via electromyography activity. RESULTS: Compared to CON, OP-PLA improved 4-km cycling TT performance (P = 0.018), and OP-CAF further improved performance when compared to OP-PLA (P = 0.050). Muscle activation was higher in OP-PLA and OP-CAF than in CON throughout the trial (P = 0.003). The pre- to post-exercise reductions in voluntary activation and potentiated twitch force were, however, similar between experimental conditions (P > 0.05). Compared to CON, OP-PLA increased the rating of perceived exertion during the first 2 km, but caffeine blunted this increase with no difference between the OP-CAF and CON conditions. CONCLUSIONS: Caffeine is ergogenic when riding against a virtual opponent, but this is not due to greater muscle activation or at the expense of greater end-exercise central or peripheral fatigue.


Asunto(s)
Rendimiento Atlético , Sustancias para Mejorar el Rendimiento , Rendimiento Atlético/fisiología , Ciclismo/fisiología , Cafeína/farmacología , Estudios Cruzados , Método Doble Ciego , Ingestión de Alimentos , Humanos , Masculino , Fatiga Muscular , Sustancias para Mejorar el Rendimiento/farmacología , Poliésteres
10.
Am J Otolaryngol ; 43(5): 103607, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35987099

RESUMEN

OBJECTIVE: To report long-term patterns of recovery and non-recovery in a large nationwide cohort of subjects with COVID-19 associated smell loss. STUDY DESIGN: Prospectively, longitudinal questionnaires. SETTING: Web-based national survey. METHODS: A longitudinal survey of adults with COVID-19 and/or sudden change in smell or taste since January 1, 2020 was launched April 10, 2020. Participants were queried again in late May 2022 regarding recovery. Data from respondents with >2 years since loss were analyzed and compared to recovery status of those more recently effected. RESULTS: 1103 responded to the survey of whom 946 met inclusion criteria. Among the 267 respondents for whom at least 2 years of follow up was available, 38.2 % reported full recovery, 54.3 % partial, and 7.5 % no recovery. For the entire cohort (all with ≥3 months since smell loss), 38.7 % reported complete recovery, 51.0 % reported partial recovery (ranging from mild complaints to severe phantosmia or dysosmia), and 10.3 % reported no improvement at all. Complete recovery of smell function was significantly higher in those under 40 years old (45.6 % compared to 32.9 % in those over 40). CONCLUSION: Although the vast majority of subjects who do recover do so within the first 3 months, long-term spontaneous recovery can occur. Rates of recovery do not seem to differ depending on when during the pandemic the loss first occurred.


Asunto(s)
COVID-19 , Trastornos del Olfato , Adulto , Anosmia/epidemiología , Anosmia/etiología , COVID-19/complicaciones , Estudios de Seguimiento , Humanos , Trastornos del Olfato/epidemiología , Trastornos del Olfato/etiología , Pandemias , SARS-CoV-2 , Olfato , Trastornos del Gusto/epidemiología , Trastornos del Gusto/etiología
11.
Am J Otolaryngol ; 43(1): 103239, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34547716

RESUMEN

OBJECTIVE: To determine which factors (demographic, symptoms, comorbidities, and treatments) are associated with recovery of smell in patients with COVID-19 associated olfactory loss. STUDY DESIGN: Prospective, longitudinal questionnaires. SETTING: National survey. METHODS: A longitudinal web-based nationwide survey of adults with COVID-19 associated smell and taste loss was launched April 10, 2020. After completing an initial entry survey, participants received detailed follow-up questionnaires 14 days, and 1, 3 and 6 months later. RESULTS: As of June 25, 2021, 798 participants met study inclusion criteria and completed 6-month questionnaires. Of demographic characteristics only age <40 years was positively associated with smell recovery (p < .003). Of symptoms, difficulty breathing was negatively associated with smell recovery (p < .004), and nasal congestion positively associated with smell recovery (p < .03). Of pre-existing comorbidities only previous head injury (p < .017) was negatively associated with smell recovery. None of the queried medications used to treat COVID were associated with better rates of smell recovery. CONCLUSIONS: Age <40 and presence of nasal congestion at time of COVID-19 infection were predictive of improved rates of smell recovery, while difficulty breathing at time of COVID-19 infection, and prior head trauma predicted worsened rates of recovery. Further study will be required to identify potential mechanisms for the other observed associations. Such information can be used by clinicians to counsel patients suffering COVID-19 associated smell loss as to prognosis for recovery.


Asunto(s)
COVID-19/complicaciones , Trastornos del Olfato/fisiopatología , Trastornos del Olfato/virología , Recuperación de la Función , Adulto , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , SARS-CoV-2 , Encuestas y Cuestionarios
12.
Sensors (Basel) ; 22(5)2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35270879

RESUMEN

Texture mapping of 3D models using multiple images often results in textured meshes with unappealing visual artifacts known as texture seams. These artifacts can be more or less visible, depending on the color similarity between the used images. The main goal of this work is to produce textured meshes free of texture seams through a process of color correcting all images of the scene. To accomplish this goal, we propose two contributions to the state-of-the-art of color correction: a pairwise-based methodology, capable of color correcting multiple images from the same scene; the application of 3D information from the scene, namely meshes and point clouds, to build a filtering procedure, in order to produce a more reliable spatial registration between images, thereby increasing the robustness of the color correction procedure. We also present a texture mapping pipeline that receives uncorrected images, an untextured mesh, and point clouds as inputs, producing a final textured mesh and color corrected images as output. Results include a comparison with four other color correction approaches. These show that the proposed approach outperforms all others, both in qualitative and quantitative metrics. The proposed approach enhances the visual quality of textured meshes by eliminating most of the texture seams.

13.
Eur J Neurosci ; 53(4): 1189-1196, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33073415

RESUMEN

Freezing of gait (FoG) is one of the main reasons for movement initiation disorders and abnormal coupling of posture and gait in Parkinson's disease (PD). Patients with FoG have poor postural control when compared to patients without FoG. However, the nature of the interrelationship between FoG and domains of postural control remains unknown. The aim of this study was to estimate the association between different domains of postural control and severity of FoG in patients with moderate-to-severe PD. Thirty patients with idiopathic PD with FoG (age range 45-80 years, Hoehn & Yahr stages 3 and 4) participated in the study. We evaluated objective (FoG-ratio during turning task) and subjective (New Freezing of Gait Questionnaire, NFoG-Q) measures of FoG severity, reactive postural adjustments in response to an external perturbation, first step anticipatory adjustment for step initiation and quiet standing stability. In the multiple regression analysis, step initiation was the strongest significant correlation of the NFoG-Q score explaining 23% of the variance of the assessment. For the objective FoG measure, mediolateral CoP amplitude in quiet standing and mediolateral CoP amplitude in step initiation explained 39% of the variance of the FoG-ratio. As main conclusions, this study identified the association between objective and subjective measure for FoG severity and postural control domains. The results support conducting step initiation training during rehabilitation of individuals with FoG.


Asunto(s)
Trastornos Neurológicos de la Marcha , Enfermedad de Parkinson , Anciano , Anciano de 80 o más Años , Marcha , Trastornos Neurológicos de la Marcha/etiología , Humanos , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Equilibrio Postural , Postura
14.
Eur J Neurosci ; 54(11): 8020-8028, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34755397

RESUMEN

In individuals with Parkinson's disease (PD), the medication induces different and inconsistent results in the spatiotemporal parameters of gait, making it difficult to understand its effects on gait. As spatiotemporal gait parameters have been reported to be affected by gait speed, it is essential to consider the gait speed when studying walking biomechanics to interpret the results better when comparing the gait pattern of different conditions. Since the medication alters the self-selected gait speed of individuals with PD, this study analysed whether the change in gait speed can explain the selective effects of l-DOPA on the spatiotemporal parameters of gait in individuals with PD. We analysed the spatiotemporal gait parameters at the self-selected speed of 22 individuals with PD under ON and OFF states of l-DOPA medication. Bayesian mediation analysis evaluated which gait variables were affected by the medication state and checked if those effects were mediated by speed changes induced by medication. The gait speed was significantly higher among ON compared with OFF medication. All the spatiotemporal parameters of the gait were mediated by speed, with proportions of mediation close to 1 (effect entirely explained by speed changes). Our results show that a change in gait speed better explains the changes in the spatiotemporal gait parameters than the ON-OFF phenomenon. As an implication for rehabilitation, our results suggest that it is possible to assess the effect of l-DOPA on improving motor symptoms related to gait disorders by measuring gait speed.


Asunto(s)
Trastornos Neurológicos de la Marcha , Enfermedad de Parkinson , Teorema de Bayes , Marcha , Trastornos Neurológicos de la Marcha/tratamiento farmacológico , Trastornos Neurológicos de la Marcha/etiología , Humanos , Levodopa/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Velocidad al Caminar
15.
Am J Physiol Regul Integr Comp Physiol ; 320(6): R812-R823, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33787348

RESUMEN

The present study analyzed the effects of local ischemia during endurance exercise on neuromuscular fatigue (NMF). Nine cyclists performed, in a counterbalanced order, two separate 4-km cycling time trials (TT) with (ISCH) or without (CONTR) induced local ischemia. NMF was characterized by using isometric maximal voluntary contractions (IMVC), whereas central [voluntary activation (VA)] and peripheral fatigue [peak torque of potentiated twitch (TwPt)] of knee extensors were evaluated using electrically evoked contractions performed before (PRE) and 1 min after (POST) the TT. Electromyographic activity (EMG), power output (PO), oxygen uptake (V̇o2), and rating of perceived exertion (RPE) were also recorded. The decrease in IMVC (-15 ± 9% vs. -10 ± 8%, P = 0.66), VA (-4 ± 3% vs. -3 ± 3%, P = 0.46), and TwPt (-16 ± 7% vs. -19 ± 14%, P = 0.67) was similar in ISCH and CONTR. Endurance performance was drastically reduced in ISCH condition (512 ± 29 s) compared with CONTR (386 ± 17 s) (P < 0.001), which was accompanied by lower EMG, PO, and V̇o2 responses (all P < 0.05). RPE was greater in ISCH compared with CONTR (P < 0.05), but the rate of change was similar throughout the TT (8.19 ± 2.59 vs. 7.81 ± 2.01 RPE.% of total time-1, P > 0.05). These results indicate that similar end-exercise NMF levels were accompanied by impaired endurance performance in ISCH compared with CONTR. These novel findings suggest that the local reduced oxygen availability affected the afferent feedback signals to the central nervous system, ultimately increasing perceived effort and reducing muscle activity and exercise intensity to avoid surpassing a sensory tolerance limit before the finish line.


Asunto(s)
Rendimiento Atlético/fisiología , Isquemia/fisiopatología , Fatiga Muscular/fisiología , Músculo Esquelético/fisiopatología , Adulto , Ciclismo/fisiología , Ejercicio Físico/fisiología , Humanos , Contracción Isométrica/fisiología , Articulación de la Rodilla/fisiología , Articulación de la Rodilla/fisiopatología , Masculino , Músculo Esquelético/fisiología
16.
Exp Physiol ; 106(8): 1710-1719, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33998067

RESUMEN

NEW FINDINGS: What is the central question of this study? Eccentric contraction exercises cause damage to muscle fibres and induce inflammatory responses. The exacerbation of this process can induce deposition of fibrous connective tissue, leading to decreased muscle function. The aim of this study was to examine the role of angiotensin-(1-7) in this context. What is the main finding and its importance? Our results show that oral treatment with angiotensin-(1-7) decreases muscle damage induced by eccentric exercise, reducing inflammation and fibrosis in the gastrocnemius and soleus muscles. This study shows a potential effect of angiotensin-(1-7) for the prevention of muscle injuries induced by physical exercise. ABSTRACT: Eccentric contraction exercises cause damage to the muscle fibres and induce an inflammatory reaction. The protective effect of angiotensin-(1-7) [Ang-(1-7)] in skeletal muscle has led us to examine the role of this peptide in modifying processes associated with inflammation and fibrogenesis induced by eccentric exercise. In this study, we sought to investigate the effects of oral administration of Ang-(1-7) formulated in hydroxypropyl ß-cyclodextrin (HPß-CD) in prevention and treatment of muscle damage after downhill running. Male Wistar rats were divided into three groups: control (untreated and not exercised; n = 10); treated/exercised HPß-CD Ang-(1-7) (n = 40); and treated/exercised HPß-CD (n = 40). Exercised groups were subjected to a single eccentric contraction exercise session on a treadmill inclined to -13° at a constant speed of 20 m/min, for 60 min. Oral administration of HPß-CD Ang-(1-7) and HPß-CD was performed 3 h before the exercise protocol and daily as a single dose, until the end of the experiment. Samples were collected 4, 12, 24, 48 and 72 h after the exercise session. The animals treated with the Ang-(1-7) showed lower levels of creatine kinase, lower levels of tumor necrosis factor-α in soleus muscle and increased levels of interleukin-10 cytokines. The inflammatory cells and deposition of fibrous connective tissue in soleus and gastrocnemius muscles were lower in the group treated with Ang-(1-7). The results of this study show that treatment with an oral formulation of Ang-(1-7) enhances the process of repair of muscle injury induced by eccentric exercise.


Asunto(s)
Condicionamiento Físico Animal , Administración Oral , Angiotensina I , Animales , Fibrosis , Masculino , Músculo Esquelético/fisiología , Fragmentos de Péptidos , Condicionamiento Físico Animal/fisiología , Ratas , Ratas Wistar
17.
J Am Coll Nutr ; 40(5): 419-428, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32790496

RESUMEN

OBJECTIVE: We investigated the effects of acute ingestion of Maytenus ilicifolia extract on metabolic and cardiopulmonary responses during a high-intensity interval exercise (HIIE), and its consequence on neuromuscular fatigue. METHODS: Ten healthy men underwent a HIIE (4 x 4 min, 3 min recovery) one hour after ingesting 400 mg of Maytenus ilicifolia extract (MIE) or placebo. Oxygen uptake (V̇O2), dioxide carbon production (V̇CO2), ventilation (V̇E) and heart rate (HR) were measured throughout the HIIE. Maximal voluntary contraction (MVC), voluntary activation (VA), and evoked 1, 10 and 100 Hz force twitch were measured before supplementation (baseline), and before (pre-HIIE) and after the HIIE (post-HIIE). RESULTS: The V̇O2, V̇E, V̇E/V̇O2 ratio and HR increased progressively throughout the HIIE under both conditions (p < 0.05). MIE increased HR, however, at bouts 1 and 2 and mean V̇O2 during HIIE. The mean respiratory exchange ratio during recovery was also reduced with MIE (p < 0.05). MVC and evoked force at 1, 10 and 100 Hz declined similarly after HIIE, regardless of the condition (MIE: -18 ± 17%, -50 ± 15%, -61 ± 13% and -34 ± 10% vs. placebo: -19 ± 15%, -48 ± 16%, -58 ± 12 and -29 ± 11%, respectively, p < 0.05). There was no effect of exercise or MIE on VA (p > 0.05). CONCLUSION: MIE increases heart rate in the first bouts and mean oxygen uptake during HIIE without changes in neuromuscular fatigue development.


Asunto(s)
Maytenus , Ejercicio Físico , Humanos , Fatiga Muscular , Oxígeno , Consumo de Oxígeno , Extractos Vegetales
18.
Exp Brain Res ; 239(2): 639-653, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33388814

RESUMEN

In response to sudden perturbations of stance stability, muscles of both legs are activated for balance recovery. In conditions that one of the legs has a reduced capacity to respond, the opposite leg is predicted to compensate by responding more powerfully to restore stable upright stance. In this investigation, we aimed to evaluate between-leg compensatory control in automatic postural responses to sudden perturbations in a situation in which plantar flexor muscles of a single leg were fatigued. Young participants were evaluated in response to a series of perturbations inducing forward body sway, with a focus on activation of plantar flexor muscles: lateral and medial gastrocnemii and soleus. Muscular responses were analyzed through activation magnitude and latency of muscular activation onset. For evaluation of balance and postural stability, we also analyzed the center of pressure and upper trunk displacement and weight-bearing asymmetry between the legs. Responses were assessed in three conditions: pre-fatigue, under single-leg fatigue, and following the recovery of muscular function. Results showed (a) compensation of the non-fatigued leg through the increased magnitude of muscular activation in the first perturbation under fatigue; (b) adaptation in the non-fatigued leg over repetitive perturbations, with a progressive decrement of muscular activation over trials; and (c) maintenance of increased muscular activation of the non-fatigued leg following fatigue dissipation. These findings suggest that the central nervous system is able to modulate the descending motor drive individually for each leg's muscles apparently based on their potential contribution for the achievement of the behavioral aim of recovering stable body balance following stance perturbations.


Asunto(s)
Pierna , Equilibrio Postural , Electromiografía , Fatiga , Humanos , Músculo Esquelético , Postura
19.
Scand J Med Sci Sports ; 31(9): 1753-1763, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33960538

RESUMEN

This study aimed to evaluate the effect of head pre-cooling on the 5-km time-trial performance of amateur runners in the heat. In a counterbalanced design, 15 male amateur runners (22.6 ± 3.5 y; VO2 max in heat 42.3 ± 4.4 mLO2 /kg/min) completed two 5-km time trials performed in the heat (35°C, 50% relative humidity). In one trial (HCOOL), participants underwent 20 min of head cooling in a temperate environment (23°C, 70% relative humidity) prior to exercise. In another trial (CON), exercise was preceded by 20 min of rest under the same temperature conditions. Exercise time was shorter in HCOOL (25 min and 36 s ± 3 min) compared to CON (27 ± 3 min; p = 0.02). Rectal temperature was reduced during the pre-exercise intervention in HCOOL (p < 0.001), but not in CON (p = 0.55). Relative changes in rectal temperature and mean head temperature were lower throughout HCOOL when compared with CON condition (p = 0.005 and p = 0.022, respectively). Mean skin temperature, heart rate, and rating of perceived exertion did not differ between HCOOL and CON conditions throughout exercise (p = 0.20, p = 0.52 and 0.31, respectively). Thermal comfort was lower in HCOOL condition in pre-exercise (p = 0.014) with no differences observed throughout exercise (p = 0.61). 5-km running performance in a hot environment was improved after a 20-min head cooling intervention, suggesting that this method may be practical as pre-cooling strategy and easily administered to both professional and amateur runners alike.


Asunto(s)
Rendimiento Atlético/fisiología , Cabeza/fisiología , Calor , Hipotermia Inducida/métodos , Carrera/fisiología , Aclimatación/fisiología , Temperatura Corporal/fisiología , Frío , Agua Potable/administración & dosificación , Frecuencia Cardíaca , Humanos , Humedad , Masculino , Consumo de Oxígeno/fisiología , Esfuerzo Físico/fisiología , Recto/fisiología , Temperatura Cutánea/fisiología , Sudoración/fisiología , Factores de Tiempo , Adulto Joven
20.
Am J Otolaryngol ; 42(4): 103001, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33773440

RESUMEN

OBJECTIVE: The association between COVID-19 and chemosensory loss has garnered substantial attention, however to date little is known about the real-life consequences of impairment in this unique patient population. The aim of this study is to evaluate the quality of life (QOL) and personal safety deficits experienced by patients with COVID-19 infection. STUDY DESIGN: Prospective, longitudinal questionnaires. SETTING: National survey. METHODS: A longitudinal web-based nationwide survey of adults with COVID-19 and/or a sudden change in smell and taste was launched April 10, 2020. Previously published questions on chemosensory-related QOL and safety events were asked at the 6-month follow-up survey. RESULTS: As of February 10, 2021, 480 eligible respondents took the 6-month questionnaire, of whom 322 were COVID-19 positive. Impact on QOL was substantial with 96% of subjects reporting at least one of the defined deficits, and over 75% reporting at least 3 of these. "Reduced enjoyment of food" was the most common complaint (87%), while 43% of subjects self-reported depression. The prevalence of safety-related issues was common in this population, with over 57% reporting at least one, and 36% reporting 2 or more events. Of the events asked, the inability to smell smoke that others could perceive was the most common at 45%. CONCLUSIONS: COVID-19 associated chemosensory losses have a real and substantial impact on both quality of life and safety, beyond mere inconvenience. The high prevalence of these issues despite a relatively short period of olfactory deficit should alert clinicians to the serious risks to an already vulnerable patient population.


Asunto(s)
COVID-19/complicaciones , Trastornos del Olfato/complicaciones , Calidad de Vida , Trastornos del Gusto/complicaciones , Adolescente , Adulto , Anciano , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Trastornos del Olfato/psicología , Trastornos del Olfato/virología , Estudios Prospectivos , Riesgo , Encuestas y Cuestionarios , Trastornos del Gusto/psicología , Trastornos del Gusto/virología , Adulto Joven
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