ABSTRACT Introduction: The strength training of superior members currently practiced in the university courses does not correspond to the real necessities of the athletes, demanding the development of optimized methods for more expressive performance gains. To create these methods, it is necessary to collect data scientifically to consolidate a solid analysis for improvement. Objective: Analyze upper limbs strength training in table tennis players. Methods: During the experiment, 20 students were randomly divided into groups to perform daily training according to the original table tennis training plan. The experimental group received a schematized protocol improving the existing teaching by adding upper limb strength training. The experiment totaled eight weeks, with one hour of training conducted twice a week. Results: In the experimental group, the attack distance index increased by 25.378%, the one-minute attack swing index increased by 0.585%, the swing index increased by 12.795%, and the technical attack index increased by 11.452%. Conclusion: The improved upper limb strength training method presented in the protocol of this article can optimize athletes’ muscle strength, increasing balance and swing ability, positively influencing the technical score and final sports performance. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMEN Introducción: El entrenamiento de fuerza de miembros superiores actualmente practicado en los cursos universitarios no corresponde a las necesidades reales de los atletas, exigiendo el desarrollo de métodos optimizados para ganancias de rendimiento más expresivas. Para la confección de estos métodos, es necesario recopilar datos de forma científica con el fin de consolidar un análisis sólido para su mejora. Objetivo: Analizar el entrenamiento de fuerza de los miembros superiores en practicantes de tenis de mesa. Métodos: Durante el experimento, 20 estudiantes se dividieron aleatoriamente en un grupo para realizar un entrenamiento diario según el plan de entrenamiento original de tenis de mesa, mientras que el grupo experimental recibió un protocolo esquematizado que mejoraba la enseñanza existente añadiendo un entrenamiento de fuerza de las extremidades superiores. El experimento duró 8 semanas, con una hora de entrenamiento dos veces por semana. Resultados: En el grupo experimental, el índice de distancia de ataque aumentó un 25,378%, el índice de balanceo de ataque de un minuto aumentó un 0,585%, el índice de balanceo aumentó un 12,795% y el índice de ataque técnico aumentó un 11,452%. Conclusión: El método mejorado de entrenamiento de la fuerza de las extremidades superiores presentado en el protocolo de este artículo puede optimizar la fuerza muscular de los atletas, aumentando el equilibrio y la capacidad de balanceo, influyendo positivamente en la puntuación técnica y en el rendimiento deportivo final. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

RESUMO Introdução: O treinamento de força de membros superiores atualmente praticados nos cursos universitários não correspondem às reais necessidades dos atletas, exigindo o desenvolvimento de métodos otimizados para ganhos de desempenho mais expressivos. Para a confecção desses métodos, é necessário efetuar-se uma coleta de dados de maneira científica afim de consolidar uma análise sólida para aprimoramento. Objetivo: Analisar o treinamento de força dos membros superiores nos praticantes de tênis de mesa. Métodos: Durante o experimento, 20 estudantes foram aleatoriamente divididos em um grupo para efetuar o treinamento diário de acordo com o plano original de treinamento do tênis de mesa, enquanto o grupo experimental recebeu um protocolo esquematizado aprimorando o ensino existente, adicionando o treinamento de força para os membros superiores. O experimento totalizou 8 semanas, com uma hora de treino realizado duas vezes por semana. Resultados: No grupo experimental, o índice de distância de ataque aumentou 25,378%, o índice de balanço de ataque de um minuto aumentou 0,585%, o índice de balanço aumentou 12,795% e o índice técnico de ataque aumentou 11,452%. Conclusão: O método aperfeiçoado de treinamento de força dos membros superiores apresentados no protocolo deste artigo pode otimizar a força muscular dos atletas, aumentando a capacidade de equilíbrio e balanço, influenciando positivamente na pontuação técnica e desempenho esportivo final. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

ABSTRACT Purpose: Oxidative stress and apoptosis contribute to the pathological basis of doxorubicin (DOX)-induced cardiotoxicity. Columbianadin (CBN) is one of the main bioactive constituents isolated from the root of Angelica pubescens. Herein, we intended to explore the potential role and molecular basis of CBN in DOX-induced cardiotoxicity. Methods: C57BL/6 mice were subjected to DOX (15 mg/kg/day, i.p.) to generate DOX-induced cardiotoxicity. CBN (10 mg/kg/day, i.p.) was administered for four week following DOX injection. Results: DOX administered markedly dampened cardiac function, increased cardiac injury, excessive reactive oxygen species (ROS) production, and cardiomyocyte loss. These alterations induced by DOX significantly alleviated by CBN treatment. Mechanistically, our results demonstrated that the CBN exerts cardioprotection role against DOX by up-regulating silent information regulator 1 (Sirt1) and decreasing acetylation of forkhead box O1 (FOXO1). Moreover, Sirt1 inhibition with Ex-527 significantly blunt the beneficial effect of CBN on DOX-induced cardiotoxicity, including cardiac dysfunction, ROS, and apoptosis. Conclusion: Collectively, CBN attenuated oxidative stress and cardiomyocyte apoptosis in DOX-induced cardiotoxicity through maintaining Sirt1/FOXO1 signaling pathway. Our results demonstrated that CBN might be used to treat DOX-related cardiotoxicity.

Human pluripotent stem cells (hPSCs)/OP9 coculture system is a widely used hematopoietic differentiation approach. The limited understanding of this process leads to its low efficiency. Thus, we used single-cell qPCR to reveal the gene expression profiles of individual CD34+ cells from different stages of differentiation. According to the dynamic gene expression of hematopoietic transcription factors, we overexpressed specific hematopoietic transcription factors (Gata2, Lmo2, Etv2, ERG, and SCL) at an early stage of hematopoietic differentiation. After overexpression, we generated more CD34+ cells with normal expression level of CD43 and CD31, which are used to define various hematopoietic progenitors. Furthermore, these CD34+ cells possessed normal differentiation potency in colony-forming unit assays and normal gene expression profiles. In this study, we demonstrated that single-cell qPCR can provide guidance for optimization of hematopoietic differentiation and transient overexpression of selected hematopoietic transcription factors can enhance hematopoietic differentiation.

ABSTRACT This paper addresses the static distortion and stress analysis of inflatable antenna structures subjected to a thermal load, which is a very important type of load experienced by such structures during service in orbit. Non-linear finite element analysis methods for inflatable structures were formulized, and the thermal stress of thin films was considered. The dynamic relaxation method was used to address the singularity problem of the stiffness matrix for the non-pre-stressed membrane structures. When the thermal load is changing, the state of the inflation gas inside the structure chamber varies, as well as the thermal stress of the membrane material. An iterative algorithm was presented to solve this coupling problem between thermal load, the structures, and inflation gas. The presented algorithm has been implemented into an own finite element code of inflatable structures. The thermal deformation and the stress distribution of a 3.2-m inflatable antenna structure were analyzed to illustrate the feasibility of the numerical method. The results indicated that the change in the state of the inflation gas adversely affects the structural performance, so the inflation gas must be considered.

OBJECTIVES: This study investigated whether the serum matrix metalloproteinase-9 level is an independent predictor of recurrence after catheter ablation for persistent atrial fibrillation. METHODS: Fifty-eight consecutive patients with persistent atrial fibrillation were enrolled and underwent catheter ablation. The serum matrix metalloproteinase-9 level was detected before ablation and its relationship with recurrent arrhythmia was analyzed at the end of the follow-up. RESULTS: After a mean follow-up of 12.1±7.2 months, 21 (36.2%) patients had a recurrence of their arrhythmia after catheter ablation. At baseline, the matrix metalloproteinase-9 level was higher in the patients with recurrence than in the non-recurrent group (305.77±88.90 vs 234.41±93.36 ng/ml, respectively, p=0.006). A multivariate analysis showed that the matrix metalloproteinase-9 level was an independent predictor of arrhythmia recurrence, as was a history of atrial fibrillation and the diameter of the left atrium. CONCLUSION: The serum matrix metalloproteinase-9 level is an independent predictor of recurrent arrhythmia after catheter ablation in patients with persistent atrial fibrillation.