RESUMO Introdução: A força conjunta dos membros inferiores desempenha um papel decisivo na capacidade competitiva nos saltadores de salto em distância. O treinamento de força especial baseado na ciência e direcionado para a força das articulações dos membros inferiores é um tópico essencial para os saltadores. Objetivo: Analisar as características de força muscular isocinética das articulações dos membros inferiores em saltadores de salto em distância. Métodos: Saltadores voluntários foram submetidos à testes de contração concêntrica isocinética dos membros inferiores e articulação do quadril. Efetuou-se também a análise do efeito do treinamento de força na lesão das articulações dos membros inferiores. Resultados: Os músculos dos joelhos dos atletas têm uma contratilidade excêntrica reduzida. O tornozelo dos atletas possui a articulação mais vulnerável a lesões no esporte. Conclusão: A força de explosão e a capacidade de contração excêntrica dos músculos extensores dos membros inferiores dos saltadores de salto longo têm o impacto mais significativo no empuxo das articulações e na velocidade de extensão. Os atletas precisam de treinamento de força muscular para desenvolver a força muscular isocinética. Isto pode efetivamente evitar lesões nos movimentos das extremidades inferiores das articulações. Os resultados da pesquisa deste trabalho podem fornecer uma base teórica específica para a formulação do treinamento científico para os saltadores de salto longo. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

ABSTRACT Introduction: Joint strength of the lower limbs plays a decisive role in the competitive ability of long jumpers. Special strength training based on science and targeted at the strength of the lower limb joints is an essential topic for long jumpers. Objective: To analyze isokinetic muscle strength characteristics of lower limb joints in long jumpers. Methods: Voluntary jumpers were submitted to isokinetic concentric contraction tests of the lower limbs and hip joints. We also analyzed the effect of strength training on lower limb joint injury. Results: The knee muscles of the athletes have reduced eccentric contractility. The ankle of the athlete has the most vulnerable joint to injuries in the sport. Conclusion: The explosive force and eccentric contractility of long jumpers’ lower limb extensor muscles have the most significant impact on joint thrust and extension speed. Athletes need muscle strength training to develop isokinetic muscle strength. This can effectively prevent injury to lower extremity joint movements. The research findings of this paper can provide a specific theoretical basis for formulating scientific training for long jumpers. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMEN Introducción: La fuerza articular de los miembros inferiores desempeña un papel decisivo en la capacidad competitiva de los saltadores de longitud. El entrenamiento de fuerza especial basado en la ciencia y dirigido a la fuerza de las articulaciones de los miembros inferiores es un tema esencial para los saltadores. Objetivo: Analizar las características de la fuerza muscular isocinética de las articulaciones de los miembros inferiores en saltadores de longitud. Métodos: Los saltadores voluntarios fueron sometidos a pruebas de contracción concéntrica isocinética de los miembros inferiores y de las articulaciones de la cadera. También se realizó un análisis del efecto del entrenamiento de fuerza en las lesiones de las articulaciones de los miembros inferiores. Resultados: Los músculos de la rodilla de los atletas tienen una contractilidad excéntrica reducida. El tobillo de los atletas tiene la articulación más vulnerable a las lesiones en el deporte. Conclusión: La fuerza de explosión y la contractilidad excéntrica de los músculos extensores de las extremidades inferiores de los saltadores de longitud tienen el impacto más significativo en el empuje articular y la velocidad de extensión. Los atletas necesitan entrenar la fuerza muscular para desarrollar la fuerza muscular isocinética. Esto puede prevenir eficazmente las lesiones en los movimientos de las articulaciones de las extremidades inferiores. Los resultados de la investigación de este trabajo pueden proporcionar una base teórica específica para la formulación del entrenamiento científico de los saltadores de longitud. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

The degradation of bisphenol A (BPA) by Fe3O4/persulfate system was investigated in aqueous solution. The influences of the initial concentrations of Fe3O4, persulfate (PS) and BPA, pH value, and initial reaction temperature on BPA removal were studied. The radical species was investigated by adding excessive dose of scavenger (methanol (MeOH) and tert-butanol (TBA)) into Fe3O4/PS system for the purpose of radical scavenging. The degradation products of BPA were detected by gas chromatography-mass spectrometry (GC-MS). The recyclability of Fe3O4 was also evaluated. The BPA removal rate of 80.7% was achieved under the following conditions: [BPA]0 = 1 mg L-1, [PS]0 = 0.2 mM, [Fe3O4]0 = 0.1 g L-1, T0 = 20 ± 1 ºC, pH0 = 6.8 ± 0.2. The results confirmed that the main free radicals in the reaction process were sulfate radicals, followed by hydroxyl radicals. Some intermediate products of BPA degradation, such as phenols, benzoquinones and benzoic acid were identified by GC-MS.

Abstract Background: The impaired glucose tolerance (IGT) is a representative prediabetes characterized by defective glucose homeostasis, and palmatine (PAL) is a natural isoquinoline alkaloid with multiple pharmacological effects. Our study aims to investigate the therapeutic effect of PAL on the impaired glucose tolerance. Methods: Male Sprague-Dawley rats were used to establish an IGT model with high fat diet (HFD). Oral glucose tolerance test (OGTT) and further biochemical analysis were conducted to determine the effect of PAL on glucose intolerance in vivo. Molecular details were clarified in a cellular model of IGT induced by Palmitate (PA) on INS-1 cells. Results: Our study demonstrated a relief of IGT with improved insulin resistance in HFD induced rats after PAL treatment. Besides, promoted pancreas islets function was validated with significantly increased β cell mass after the treatment of PAL. We further found out that PAL could alleviate the β cell apoptosis that accounts for β cell mass loss in IGT model. Moreover, MAPK signaling was investigated in vivo and vitro with the discovery that PAL regulated the MAPK signaling by restricting the ERK and JNK cascades. The insulin secretion assay indicated that PAL significantly promoted the defective insulin secretion in PA-induced INS-1 cells via JNK rather than ERK signaling. Furthermore, PAL treatment was determined to significantly suppress β cell apoptosis in PA-induced cells. We thus thought that PAL promoted the PA-induced impaired insulin release by inhibiting the β cell apoptosis and JNK signaling in vitro. Conclusion: In summary, PAL ameliorates HFD-induced IGT with novel mechanisms.