RESUMEN
Nitric oxide(NO) is essential for reducing post-harvest product senescence and storage losses. NO may slow down the senescence of agricultural products and improve their quality, suggestive of its great potential in the postharvest preservation of agricultural products. The development of NO as a post-harvest preservative is supported by the investigation of its role and mechanism in agricultural product ageing. In this review, the mechanisms of NO in the post-harvest senescence of agricultural products were explored. NO is produced mainly via the nitrate reductase(NR) and NO synthase-like(NOS) pathways. Usually, NO donors include sodium nitroprusside (SNP), S-nitroso-N-acetyl-DL-penicillamine (SNAP), S-nitrosoglutathione(GSNO) and NO gas fumigation. NO delays agricultural product senescence by regulating ROS metabolism, enhancing antioxidant activity, reducing respiration, activating cell wall metabolism, inhibiting ethylene synthesis, and promoting energy metabolism. Melatonin(MT), ethylene(ETH), hydrogen gas(H
RESUMEN
Starved larvae of the silversides O. hatcheri (2- and 5-days-old) and Odontesthes bonariensis (5-days-old) were used to compare the oxygen consumption rates at 0, 5, 10, 20 and 30 ppt salinity. Oxygen consumption of O. hatcheri and O. bonariensis was minimal at 0 and 10 ppt, respectively, salinities close to those encountered in areas inhabited by these fishes. In both species, oxygen consumption rates thereafter increased with increasing salinity, and then abruptly decreased at 30 ppt. Lower consumption at extreme salinities might be a result of reduced activity, which in itself was salinity-modulated. Differences in activity may explain the fact that oxygen consumption rates of 5-day-old larvae were higher than 2-day-old larvae, which still possess yolk-sac. In this case, starved larvae incurred in higher metabolic demand due to the continuous swimming in the search for food.
As larvas em inanição de peixe-rei O. hatcheri (2 e 5 dias de idade) e Odontesthes bonariensis (5 dias de idade) foram usadas para comparar as taxas de consumo de oxigênio em salinidades de 0, 5, 10, 20 e 30 ppt. As taxas de consumo de oxigênio de O. hatcheri e O. bonariensis foram mínimas a 0 e 10 ppt, respectivamente, salinidades próximas aquelas encontradas nas áreas onde estes peixes habitam. Em seguida, em ambas as espécies, as taxas de consumo de oxigênio aumentaram com o incremento da salinidade, e abruptamente caíram a 30 ppt. As taxas de consumo mais baixas em salinidades extremas podem ser resultado da atividade reduzida, sendo portanto modulada pela salinidade. Diferenças na atividade possivelmente explicam o fato das taxas de consumo de oxigênio de larvas de 5 dias de idade serem maiores em comparação a larvas de 2 dias, ainda com saco vitelínico. Neste caso, larvas em inanição impõem um maior gasto metabólico devido a natação contínua em busca de alimento.
RESUMEN
Objective:It is very important that oxidative stress is estimated for us to understand a player's condition in the field of sports. The purpose of this study was to investigate whether electroacupuncture has an effect on exercise-induced oxidative stress.<BR>Methods:Ten healthy male volunteers participated in both the electroacupuncture (EA) group and the control group in a crossover design. EA at a frequency of 2 Hz and optimum intensity was performed in the subjects for 10 minutes in both the medial vastus muscles. During ergometer exercise by ramp load, respiratory metabolism including the RC point was recorded as the indication of energy metabolism. Blood was collected from the fingertips of the subjects, and then their levels of oxidative stress (d-ROMs test) and antioxidative (BAP test) were determined by using a Free Radical Analytical System (FRAS4, Wismell Instruments). Six measurements were taken;at rest, immediately after EA and following exercise, and at 20, 40, and 60 minutes following exercise.<BR>Results:The RC point was significantly prolonged in the EA group compared with the control group. The level of oxidative stress (d-ROMs test) in the control group increased significantly at 20 minutes following exercise compared with rest (before exercise) and this increase was sustained until 60 minutes after exercise. In contrast, it did not significantly change in the EA group. Whereas the antioxidative level (BAP test) in the EA group significantly increased immediately following exercise compared with rest (before exercise), it did not increase in the control group.<BR>Conclusion:These results suggest that electroacupuncture might enhance the antioxidative level (BAP test) and inhibit the level of oxidative stress (d-ROMs test) by effecting a change in respiratory metabolism. We propose that electroacupuncture might be useful for sports conditioning.