RESUMO Introdução: Investigações buscando diferentes formas de treinamento sempre atraíram a atenção de pessoas nos círculos esportivos pelo mundo. O treino para testes de força também é uma parte importante do condicionamento físico de atletas. Objetivo: Explorar os efeitos de diferentes cargas e regimes de treino na resistência cardiorrespiratória de praticantes de atletismo. Métodos: Um total de 50 estudantes do sexo masculino de uma universidade foi selecionado para o experimento, sendo 30 da equipe de atletismo da universidade e 20 estudantes regulares. Resultados: Com cargas de 75W, 125W, ou 150W, houve diferença significativa no R entre o primeiro e o terceiro estágios (p<0,05); quando a carga aplicada ao time de corrida de média e longa distância foi de 25W e 125W, houve diferença significativa no VE dos mesmos estágios; quando a carga aplicada foi de 100W, houve diferença significativa no R entre o primeiro e segundo estágios (p<0,05). Conclusões: Nos testes de exercício com carga, a resistência cardiorrespiratória e a energia metabólica das diferentes equipes de treinamento foram melhores no terceiro estágio que no primeiro e segundo estágio. Nível de evidência II; Estudos terapêuticos – investigação de resultados de tratamento.

ABSTRACT Introduction: The research of different training has always attracted the attention of people in sports circles all over the world. Training for strength testing is also an important part of athletes’ physical training. Objective: To explore the effects of different training loads and training ratios on the cardiorespiratory endurance of track and field athletes. Methods: A total of 50 male students from a university were selected for the experiment, 30 from the university's track and field training team, and 20 ordinary students. Results: When the load is 75W, 125W, or 150W there is a significant difference in R between the first stage and the third stage (p<0.05); when the load of the middle and long distance running team is 25W and 125W, there is a significant difference between the VE of the third stage and the first stage; when the load is 100W, there is a significant difference in R between the first and second stages (P<0.05). Conclusions: In the exercise load test, the cardiorespiratory endurance and energy metabolism characteristics of the different training teams in the third stage were better than those in the first and second stages. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMEN Introducción: Investigaciones buscando diferentes formas de entrenamiento siempre atrajeron la atención de las personas en los círculos deportivos por el mundo. El entrenamiento para pruebas de fuerza también es una parte importante de la preparación física de atletas. Objetivo: Explorar los efectos de diferentes cargas y regímenes de entrenamiento en la resistencia cardiorrespiratoria de practicantes de atletismo. Métodos: Fue seleccionado un total de 50 estudiantes del sexo masculino de una universidad para el experimento, siendo 30 del equipo de atletismo de la universidad y 20 estudiantes regulares. Resultados: Con cargas de 75W, 125W o 150W, hubo diferencia significativa en el R entre la primera y la tercera etapa (p<0,05); cuando la carga aplicada al equipo de corrida de media y larga distancia fue de 25W y 125W, hubo diferencia significativa en el VE de las mismas etapas; cuando la carga aplicada fue de 100W, hubo diferencia significativa en el R entre la primera y la segunda etapa (p<0,05). Conclusiones: En las pruebas de ejercicio con carga, la resistencia cardiorrespiratoria y la energía metabólica de los diferentes equipos de entrenamiento fueron mejores en la tercera etapa que en la primera y la segunda. Nivel de evidencia II; Estudios terapéuticos – investigación de resultados de tratamiento.

Resumo Introdução Atualmente, são limitadas as informações acerca da relação entre o polimorfismo C47T de superóxido dismutase 2 (SOD2) dependente de manganês e suscetibilidade à perda auditiva induzida pelo ruído (PAIR). Objetivo O objetivo desta metanálise foi esclarecer a associação entre o polimorfismo C47T de SOD2 e PAIR. Método Foram feitas buscas no PubMed e Web of Science para coleta de dados. Foram incluídos todos os estudos no idioma inglês, com dados suficientes e completos de casos e controles sobre a relação entre o polimorfismo C47T de SOD2 e PAIR. Foram identificados três estudos qualificados, que abrangeram 1.094 indivíduos. Foram calculadas as razões das chances (odds ratio, OR) acumuladas e intervalos de confiança (IC) de 95% para que fosse avaliada a potência da associação entre o polimorfismo C47T de SOD2 e PAIR. Resultados Não foi encontrada uma associação significativa entre o polimorfismo C47T de SOD2 e risco de PAIR com as seguintes combinações: T vs. C (OR = 0,83, IC 95% = 0,63-1,09); TT vs. CC (OR = 0,49, IC 95% = 0,22-1,09); CT vs. CC (OR = 0,54, IC 95% = 0,25-1,17); TT vs. CC + CT (OR = 0,82, IC 95% = 0,50-1,32); CC vs. TT + TC (OR = 0,49, IC 95% = 0,23-1,04). Contudo, na análise de subgrupo, foi encontrada uma associação significativa para TT vs. CC + CT (OR = 0,77, 95% CI = 0,42-1.41) na população chinesa. Conclusão A presente metanálise sugere que o polimorfismo C47T de SOD2 demonstra associação significativa com maior risco de PAIR na população chinesa. Há necessidade de novos estudos de grande porte bem concebidos, para confirmação dessa associação.

Abstract Introduction Currently, there is limited information about the relationship between manganese superoxide dismutase (sod2) c47t polymorphism and susceptibility to noise-induced hearing loss (NIHL). Objective The aim of this meta-analysis was to clarify the association between SOD2 C47T polymorphism and NIHL. Methods A search in PubMed and Web of Science was performed to collect data. All full-text, English-written studies containing sufficient and complete case-and-control data about the relationship between SOD2 C47T polymorphism and NIHL were included. Three eligible studies, comprising 1094 subjects, were identified. pooled odds ratios (ORs) and 95% confidence intervals (CI) were calculated to evaluate the strength of the association between SOD2 C47T polymorphism and NIHL. Results No significant association between C47T polymorphism and risk of NIHL was found with the following combinations: T vs. C (OR = 0.83; 95% CI = 0.63–1.09); TT vs. CC (OR = 0.49; 95% CI = 0.22–1.09); CT vs. CC (OR = 0.54; 95% CI = 0.25–1.17); TT vs. CC + CT (OR = 0.82; 95% CI = 0.50–1.32); CC vs. TT + TC (OR = 0.49; 95% CI = 0.23–1.04). However, in subgroup analysis, a significant association was found for TT vs. CC + CT (OR = 0.77; 95% CI = 0.42–1.41) in the Chinese population. Conclusion The present meta-analysis suggests that SOD2 C47T polymorphism is significantly associated with increased risk of NIHL in the Chinese population. Further large and well-designed studies are needed to confirm this association.

In order to develop new-typed multifunctional composite nanofibers, PANI/Fe3O4/PVP flexible bifunctional composite nanofibers with simultaneous electrical conduction and magnetism have been successfully fabricated via a facile electrospinning technology. Polyvinyl pyrrolidone (PVP) is used as a matrix to construct composite nanofibers containing different amounts of polyaniline (PANI) and Fe3O4 nanoparticles (NPs). The bifunctional composite nanofibers simultaneously possess excellent electrical conductivity and magnetic properties. The electrical conductivity reaches up to the order of 10-3 S · cm-1. The electrical conductivity and saturation magnetization of the composite nanofibers can be respectively tuned by adding various amounts of PANI and Fe3O4 NPs. The obtained electricity-magnetism bifunctional composite nanofibers are expected to possess many potential applications in areas such as electromagnetic interference shielding, special coating, microwave absorption, molecular electronics and future nanomechanics. More importantly, the design concept and construct technique are of universal significance to fabricate other bifunctional one-dimensional nanostructures.

Abstract Postharvest lettuce often lose water, thus affecting both its market value and consumer acceptance. However, the mechanism of the water-loss is still waiting well exploration. The aim of the present study was to investigate the effect of a foliar application of ABA on the fresh weight-loss and the chlorophyll content of postharvest lettuce as well as its association with the regulation of stomata. The present data demonstrated that exogenously application of ABA, in a concentration range of 0 to 100 µM, significantly lowered the fresh weight-loss of postharvest lettuce. ABA also delayed chlorophyll reduction during ambient storage, but this protective effect was ABA concentration-dependent. Among the tested ABA concentrations, 50 µM or lower ABA produced an inhibition effect on chlorophyll degradation in postharvest lettuce leaves. The results demonstrated that the exogenous ABA treatment can obviously reduce the transpiration rate of lettuce leaves by promoting the stomatal closure of postharvest lettuce, therefore eventually delay fresh weight-loss. The present study primarily showed that the application of exogenous ABA, which originated from a naturally-produced phytohormone, has a great potential in retaining the freshness of postharvest lettuce that is stored in an ambient condition, although possible practical application still need to be further evaluated.

Tetrametilpirazina (TMP), o principal componente do extrato de Ligusticum wallichi Franchat (erva chinesa), apresenta propriedades neuroprotetoras na isquemia. Nesse estudo, avaliamos seus efeitos protetores nas células de Schwann (SC), cultivando-as na presença de condições de depleção de oxigênio da glicose (OGD) e medindo a sobrevivência dos nervos de ratos isquêmicos pelo resfriamento. No modelo de lesão isquêmica em SC induzida por OGD, demonstramos que o tratamento com TMP não somente reduziu as perdas de viabilidade celular induzida por OGD, a morte celular, a apoptose de SC dose-dependente e inibiu a liberação de LDH, mas, também, suprimiu a infra-regulação do Vcl-2 e a supra-regulação de Bax e caspase-3, e inibiu a consequente ativação da caspase-3. No modelo de nervo isquêmico por resfriamento, observamos que a exposição prolongada ao resfriamento por quatro semanas estava, marcadamente, associada com a ausência de SC, com o decréscimo da viabilidade celular e a apoptose em segmentos de nervo incubados na solução da Universidade de Wisconsin apenas. Entretanto, a TMP atenuou o dano no segmento do nervo preservando SC e antagonizando a diminuição da viabilidade da fibra nervosa e o aumento das células TUNEL-positiva de modo dose-dependente. De forma conjunta, nossos resultados indicam que o TMP não só fornece efeitos protetores em um modelo de dano semelhante à isquemia de SC de ratos cultivados pela regulação de BCl-2, Bax e caspase 3, mas, também, aumenta a sobrevivência celular e suprime a apoptose no modelo de isquemia por resfriamento por exposição prolongada por quatro semanas. Então, TMP pode ser uma estratégia terapêutica eficaz para prevenir doenças isquêmicas do sistema nervoso periférico e melhora a armazenagem do nervo periférico.

Tetramethylpyrazine (TMP), a major active ingredient of Ligusticum wallichi Franchat extract (a Chinese herb), exhibits neuroprotective properties in ischemia. In this study, we assessed its protective effects on Schwann cells (SCs) by culturing them in the presence of oxygen glucose deprivation (OGD) conditions and measuring cell survival in cold ischemic rat nerves. In the OGD-induced ischemic injury model of SCs, we demonstrated that TMP treatment not only reduced OGD-induced cell viability losses, cell death, and apoptosis of SCs in a dose-dependent manner, and inhibited LDH release, but also suppressed OGD-induced downregulation of Bcl-2 and upregulation of Bax and caspase-3, as well as inhibited the consequent activation of caspase-3. In the cold ischemic nerve model, we found that prolonged cold ischemic exposure for four weeks was markedly associated with the absence of SCs, a decrease in cell viability, and apoptosis in preserved nerve segments incubated in University of Wisconsin solution (UWS) alone. However, TMP attenuated nerve segment damage by preserving SCs and antagonizing the decrease in nerve fiber viability and increase in TUNEL-positive cells in a dose-dependent manner. Collectively, our results indicate that TMP not only provides protective effects in an ischemia-like injury model of cultured rat SCs by regulating Bcl-2, Bax, and caspase-3, but also increases cell survival and suppresses apoptosis in the cold ischemic nerve model after prolonged ischemic exposure for four weeks. Therefore, TMP may be a novel and effective therapeutic strategy for preventing peripheral nervous system ischemic diseases and improving peripheral nerve storage.

Intramuscular fat (IMF) content plays an important role in meat quality. Many genes involved in lipid and energy metabolism were identified as candidate genes for IMF deposition, since genetic polymorphisms within these genes were associated with IMF content. However, there is less information on the expression levels of these genes in the muscle tissue. This study aimed at investigating the expression levels of sterol regulating element binding protein-1c (SREBP-1c), diacylglycerol acyltransferase (DGAT-1), heart-fatty acids binding protein (H-FABP), leptin receptor (LEPR) and melanocortin 4 receptor (MC4R) genes and proteins in two divergent Banna mini-pig inbred lines (BMIL). A similar growth performance was found in both the fat and the lean BMIL. The fat meat and IMF content in the fat BMIL were significantly higher than in the lean BMIL, but the lean meat content was lower. The serum triacylglycerol (TAG) and free fatty acid (FFA) contents were significantly higher in the fat than in the lean BMIL. The expression levels of SREBP-1c, DGAT-1 and H-FABP genes and proteins in fat BMIL were increased compared to the lean BMIL. However, the expression levels of LEPR and MC4R genes and proteins were lower.

As a precursor, pimelic acid plays an important role in biotin biosynthesis pathway of Bacillus subtilis. Fermentations supplemented with pimelic acid could improve the production of biotin, however, with a disadvantage-high cost. So it is necessary to improve the biosynthesis of pimelic acid via genetic engineering in B. subtilis. In this study, we constructed a recombinant B. subtilis strain for improving the synthesis of pimelic acid, in which a maltose-inducible Pglv promoter was inserted into the upstream of the cistron bioI-orf2-orf3 and, meanwhile, flanked by the tandem cistrons via a single crossover event. The copy number of the integrant was amplified by high-concentration resistance screen and increased to 4-5 copies. The production of pimelic acid from multiple copies integrant was about 4 times higher than that from single copy (1017.13 μg/ml VS. 198.89 μg/ml). And when induced by maltose the production of pimelic acid was about 2 times of that under non-induction conditions (2360.73 μg/ml VS. 991.59 μg/ml). Thus, these results demonstrated that the production of pimelic acid was improved obviously through reconstructed B. subtilis. It also suggested that our expression system provided a convenient source of pimelic acid that would potentially lower the cost of production of biotin from engineered B. subtilis.