Paula Felippe Martinez

Myocardial myostatin in spontaneously hypertensive rats with heart failure

BACKGROUND Myostatin has been shown to regulate skeletal and cardiac muscle growth. However, its status on long-term hypertrophied myocardium has not been addressed. The purpose of this study was to evaluate the expression of myocardial myostatin and its antagonist follistatin in spontaneously hypertensive rats (SHR) with heart failure. METHODS Eighteen-month-old SHR were evaluated to identify clinical features of heart failure such as tachypnea/labored respiration and weight loss. After heart failure was detected, rats were subjected to echocardiogram and euthanized. Age-matched normotensive Wistar-Kyoto (WKY) rats were used as controls. Myostatin and follistatin protein expression was assessed by Western blotting. Statistical analysis was performed by Students t test. RESULTS All SHR (n=8) presented right ventricular hypertrophy and five had lung congestion. SHR had left chambers hypertrophy and dilation (left atrial diameter: WKY 5.73±0.59; SHR 7.28±1.17mm; p=0.004; left ventricular (LV) diastolic diameter/body weight ratio: WKY 19.6±3.1; SHR 27.7±4.7mm/kg; p=0.001), and LV systolic dysfunction (midwall fractional shortening: WKY 34.9±3.31; SHR 24.8±3.20%; p=0.003). Myocyte diameter (WKY 23.1±1.50, SHR 25.5±1.33μm; p=0.004) and myocardial interstitial collagen fraction (WKY 4.86±0.01; SHR 8.36±0.02%; p<0.001) were increased in the SHR. Myostatin (WKY 1.00±0.16; SHR 0.77±0.23 arbitrary units; p=0.035) and follistatin (WKY 1.00±0.35; SHR 0.49±0.18 arbitrary units; p=0.002) expression was lower in SHR. Myostatin and follistatin expression negatively correlated with LV diastolic diameter-to-body weight ratio and LV systolic diameter, and positively correlated with midwall fractional shortening. CONCLUSION Myostatin and follistatin protein expression is reduced in the long-term hypertrophied myocardium from spontaneously hypertensive rats with heart failure.

Autonomic modulations of heart rate variability are associated with sports injury incidence in sprint swimmers

ABSTRACT Objectives: Young athletes’ participation in competitive sports is becoming increasingly common, and this increased involvement raises concerns about the occurrence of overtraining and sports injuries. Since these issues are poorly understood, this study analyzed heart rate variability, stress/recovery relationship, and sports injury incidence during a training macrocycle of young sprint and endurance swimmers. Methods: Thirty teenage swimmers (aged 12 to 17 years) were divided into two groups as follows: Sprint (n = 17) and Endurance (n = 13). Subjects were evaluated over 20 weeks, based on the following three schedules: general, specific, and competitive. In addition to heart rate variability and sports injury incidence, the Recovery-Stress-Questionnaire of Athletes was used to analyse stress/recovery states in athletes. All procedures were developed at the initial moment and at the end of each periodization step. Results: The Sprint group presented a reduced standard deviation of normal-normal beats (73.0 ± 6.6 vs. 54.1 ± 3.5 ms; p < 0.05) and root mean square of the successive differences (55.3 ± 6.2 vs. 42.0 ± 3.7 ms; p < 0.01) from the period of general preparation until the time of competition. Recovery-stress monitoring was affected only by the swimming training periodization (p < 0.05). During the general period, differences between recovery and stress scales were correlated directly with the root mean square of the successive differences (r = 0.576; p = 0.001), the standard deviation of instantaneous variability beat-to-beat (r = 0.521; p = 0.003) and the triangular index (r = 0.476; p = 0.008). Differences between general recovery and stress scales were inversely correlated with geometric indexes after the specific training period. Moreover, the Sprint group showed a higher incidence of sports injury than the Endurance group (0.0214 ± 0.0068 vs. 0.0136 ± 0.0050 cases/1000 hours). Conclusion: Sprint training was associated with progressive activation of the sympathetic nervous system as well as a higher incidence of sports injury in comparison to endurance swimming during a training macrocycle.

Effects of early aldosterone antagonism on cardiac remodeling in rats with aortic stenosis-induced pressure overload

UNLABELLED Aldosterone plays a pivotal role in the pathophysiology of systolic heart failure. However, whether early aldosterone antagonism improves cardiac remodeling during persistent pressure overload is unsettled. We evaluated the effects of aldosterone antagonist spironolactone on cardiac remodeling in rats with ascending aortic stenosis (AS). METHODS Three days after inducing AS, weaning rats were randomized to receive spironolactone (AS-SPR, 20mg/kg/day) or no drug (AS) for 18weeks, and compared with sham-operated rats. Myocardial function was studied in isolated left ventricular (LV) papillary muscles. STATISTICAL ANALYSES ANOVA or Kruskal-Wallis tests. RESULTS Echocardiogram showed that LV diastolic (Sham 8.73±0.57; AS 8.30±1.10; AS-SPR 9.19±1.15mm) and systolic (Sham 4.57±0.67; AS 3.61±1.49; AS-SPR 4.62±1.48mm) diameters, left atrial diameter (Sham 5.80±0.44; AS 7.15±1.22; AS-SPR 8.02±1.17mm), and LV mass were higher in AS-SPR than AS. Posterior wall shortening velocity (Sham 38.5±3.8; AS 35.6±5.6; AS-SPR 31.1±3.8mm/s) was lower in AS-SPR than Sham and AS; E/A ratio was higher in AS-SPR than Sham. Developed tension was lower in AS and AS-SPR than Sham. Time to peak tension was higher in AS-SPR than Sham and AS after post-rest contraction. Right ventricle weight was higher in AS-SPR than AS, suggesting more severe heart failure in AS-SPR than AS. Interstitial collagen fractional area and myocardial hydroxyproline concentration were higher in AS than Sham. Metalloproteinase-2 and -9 activity, evaluated by zymography, did not differ between groups. CONCLUSION Early spironolactone administration causes further hypertrophy in cardiac chambers, and left ventricular dilation and dysfunction in rats with AS-induced chronic pressure overload.

Heart Rate Variability in Coexisting Diabetes and Hypertension

Heart Rate Variability in Coexisting Diabetes and Hypertension Paula F. Martinez1 and Marina P. Okoshi2 Faculdade de Fisioterapia, Universidade Federal de Mato Grosso do Sul,1 Campo Grande Brazil Departamento de Clínica Médica Faculdade de Medicina de Botucatu, Universidade Estadual de São Paulo (UNESP),2 Botucatu, SP Brazil Short Editorial regarding the article: Effects of Coexistence Hypertension and Type II Diabetes on Heart Rate Variability and Cardiorespiratory Fitness

Could current factors be associated with retrospective sports injuries in Brazilian jiu-jitsu? A cross-sectional study

BackgroundBrazilian jiu-jitsu is characterized by musculoskeletal disorders and high occurrence of sports injuries. The present study was aimed to analyze some internal factors, as well as to describe occurrence and characteristics of retrospective musculoskeletal injuries in different age groups of Brazilian jiu-jitsu practitioners.MethodsOne hundred ninety-three Brazilian jiu-jitsu practitioners, which were divided into three age groups: Adolescent, Adult, and Master. Besides anthropometric characterization, standard clinical tests were conducted to analyze the global and segmental joint flexibility, lumbar spine range of motion, and handgrip strength. Sports injury occurrence and total physical activity were obtained from an adapted morbidity survey and International Physical Activity Questionnaire - Short Form (IPAQ-SF), respectively.ResultsA total of 247 cases of retrospective injuries was registered (1.27 injury/ participant). Occurrence of rectus femoral muscle retraction in the right leg was increased within Master. Adult and Master have exhibited higher occurrence of sports injuries than Adolescent group (p < 0.05). Joint injuries were the most common sports-related injuries by all Brazilian jiu-jitsu practitioners. While female gender and exposure time constituted the most predictive variables for sports injury occurrence in Adolescent, graduation level was more associated with sports injuries occurrence in Adult.ConclusionsJoint injuries derived from combat demands were the main sports injury in all age categories of Brazilian jiu-jitsu. Master subjects presented a higher occurrence of clinical changes and retrospective musculoskeletal injuries in relation to other age groups. Female gender and exposure time constituted the main predictive factors in adolescent subjects, while graduation category was more directly associated with retrospective injury onset in the Adult group.

Incidence of low back pain according to physical activity level in hospital workers

JUSTIFICATIVA E OBJETIVOS: O ambiente hospitalar integra uma serie de riscos decorrentes de fatores fisicos, quimicos, psicossociais e ergonomicos, que podem ser prejudiciais a diferentes profissionais da area de saude. Este estudo teve por objetivo avaliar o nivel de atividade fisica, a presenca de fatores de risco musculoesqueleticos e a ocorrencia de lombalgia em profissionais de enfermagem de Centro de Materiais e Esterilizacao hospitalar. METODOS: A casuistica integrou 56 individuos de ambos os generos, trabalhadores da Associacao Beneficente de Campo Grande/MS-Hospital Santa Casa. Os participantes foram alocados em dois grupos: G1 (insuficientemente ativos, n=27) e G2 (suficientemente ativos, n=29). Alem do nivel de atividade fisica, foram realizadas analises antropometricas, de ocorrencia de dor e incapacidade funcional, flexibilidade e resistencia muscular. RESULTADOS: A ocorrencia de lombalgia foi menor em G2 (13 casos; 44,8%) que em G1 (24 casos; 88,9%). Indice de massa corporal, intensidade da dor e indice de incapacidade funcional foram menores em G2. O tempo de atividade fisica foi menor em G1. Resistencia dos musculos abdominais foi maior em G2. CONCLUSAO: Em profissionais de enfermagem, o nivel de atividade fisica influencia a ocorrencia de lombalgia, intensidade de dor e indice de incapacidade funcional.

Sports injuries in soccer according to tactical position: a retrospective survey

Introduction: In soccer, the players’ positions have been associated with specific functional overload, which may cause sports injuries. Objective: To investigate the occurrence and characterize sport injuries according to soccer player position. Methods: 232 male soccer players (129 professionals and 103 amateurs) from different sport teams in Mato Grosso do Sul, Brazil, were distributed in groups according to their soccer player position. Besides anthropometric characteristics, sports injuries were registered by using a referred morbidity survey. The occurrence of injuries was analyzed by means of the Goodman Test. Logistic regression models were used to investigate the relationship between different risk factors and the occurrence/-recurrence of sports injuries. Results: Forwards showed higher occurrence rates of sport injuries than other soccer position groups. Joint injuries in lower limbs constituted the most frequent registered cases. Muscle injuries in the back region were the most registered sports injuries among midfielders, while muscle damages in lower limbs were the primary injuries registered for other line positions. In the etiologic context, contact was the main cause of sports injuries in all groups. Most athletes (195) reported recurrence of sports injuries. Conclusion: The occurrence of sports injuries was higher among forwards. Traumatic joint and muscle injuries were the most prevalent registers in all line positions.

Lesões musculoesqueléticas em praticantes de judô

A pratica de judo integra situacoes variadas de contato fisico e exigencias especificas, tornando-o uma modalidade competitiva e com alto indice de lesoes musculoesqueleticas (LME). Este estudo transversal teve por objetivo descrever a epidemiologia de LME e analisar a relacao entre diferentes caracteristicas e a ocorrencia de lesao em judocas. A casuistica integrou 111 participantes de ambos os sexos. Para tomar informacoes sobre lesoes, utilizou-se um inquerito de morbidade referida. Para analise estatistica, foi empregado o teste de Goodman de proporcoes multinomiais. A relacao entre fatores associados com LME foi avaliada por meio de regressao logistica. Foram relatados 135 LME, com prevalencia de 65% (72 esportistas), totalizando 1,22 LME/atleta. A maioria dos relatos foi constituida por lesoes articulares decorrentes de traumas (n=50 casos, 37%), sendo que entorse de tornozelo (25,2%) e luxacao de ombro (17,8%) foram os casos com maior frequencia. Entre as lesoes osseas, verificou-se maior proporcao de casos graves (25 casos; 18,5%). Sexo e carga horaria semanal constituiram-se como as principais caracteristicas preditivas para ocorrencia de LME no judo (p<0,001). Conclui-se que as lesoes articulares traumaticas em tornozelo e ombro foram as principais LME no judo. Sexo masculino e maior carga horaria semanal constituiram-se como as principais caracteristicas preditivas de lesao entre judocas.

Lesiones músculo-esqueléticas en practicantes de judo

A pratica de judo integra situacoes variadas de contato fisico e exigencias especificas, tornando-o uma modalidade competitiva e com alto indice de lesoes musculoesqueleticas (LME). Este estudo transversal teve por objetivo descrever a epidemiologia de LME e analisar a relacao entre diferentes caracteristicas e a ocorrencia de lesao em judocas. A casuistica integrou 111 participantes de ambos os sexos. Para tomar informacoes sobre lesoes, utilizou-se um inquerito de morbidade referida. Para analise estatistica, foi empregado o teste de Goodman de proporcoes multinomiais. A relacao entre fatores associados com LME foi avaliada por meio de regressao logistica. Foram relatados 135 LME, com prevalencia de 65% (72 esportistas), totalizando 1,22 LME/atleta. A maioria dos relatos foi constituida por lesoes articulares decorrentes de traumas (n=50 casos, 37%), sendo que entorse de tornozelo (25,2%) e luxacao de ombro (17,8%) foram os casos com maior frequencia. Entre as lesoes osseas, verificou-se maior proporcao de casos graves (25 casos; 18,5%). Sexo e carga horaria semanal constituiram-se como as principais caracteristicas preditivas para ocorrencia de LME no judo (p<0,001). Conclui-se que as lesoes articulares traumaticas em tornozelo e ombro foram as principais LME no judo. Sexo masculino e maior carga horaria semanal constituiram-se como as principais caracteristicas preditivas de lesao entre judocas.

Musculoskeletal injuries in judo practitioners

A pratica de judo integra situacoes variadas de contato fisico e exigencias especificas, tornando-o uma modalidade competitiva e com alto indice de lesoes musculoesqueleticas (LME). Este estudo transversal teve por objetivo descrever a epidemiologia de LME e analisar a relacao entre diferentes caracteristicas e a ocorrencia de lesao em judocas. A casuistica integrou 111 participantes de ambos os sexos. Para tomar informacoes sobre lesoes, utilizou-se um inquerito de morbidade referida. Para analise estatistica, foi empregado o teste de Goodman de proporcoes multinomiais. A relacao entre fatores associados com LME foi avaliada por meio de regressao logistica. Foram relatados 135 LME, com prevalencia de 65% (72 esportistas), totalizando 1,22 LME/atleta. A maioria dos relatos foi constituida por lesoes articulares decorrentes de traumas (n=50 casos, 37%), sendo que entorse de tornozelo (25,2%) e luxacao de ombro (17,8%) foram os casos com maior frequencia. Entre as lesoes osseas, verificou-se maior proporcao de casos graves (25 casos; 18,5%). Sexo e carga horaria semanal constituiram-se como as principais caracteristicas preditivas para ocorrencia de LME no judo (p<0,001). Conclui-se que as lesoes articulares traumaticas em tornozelo e ombro foram as principais LME no judo. Sexo masculino e maior carga horaria semanal constituiram-se como as principais caracteristicas preditivas de lesao entre judocas.