The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L （light）： 12D （dark） with lights on at 06：00...The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L （light）： 12D （dark） with lights on at 06：00 and off at 18：00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00：00, 04：00, 08：00, 12：00, 16：00 and 20：00 with 60 turtles each （Initial body weight 88.27 - 0.09 g）. Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate （SGR） and RNA/ DNA：SGR=t.1586RNA/DNA-0.7097 （r = 0.9328, P = 0.0066）. The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12：00 were the lowest from the six groups （P 〈 0.05）. Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight （FBW）, higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total.展开更多
The effect of ultraviolet （UV） radiation on marine organisms has been an important focus of recent research, with depletion of the ozone layer resulting in increased UV radiation at high latitudes. Several studies h...The effect of ultraviolet （UV） radiation on marine organisms has been an important focus of recent research, with depletion of the ozone layer resulting in increased UV radiation at high latitudes. Several studies have identified negative impacts of UV radiation on the biology of zooplanktonic organisms. This study used the RNA/DNA ratio as a measure of stress in copepod assemblages from Fildes Bay in Antarctica and Quintay Bay on the central coast of Chile, two areas with high UV radiation but different photobiologic histories. Controlled time-light experiments were performed with copepods from the two locations, exposing them to white light, UV light, or darkness. The results showed different responses to UV radiation. Copepods from Fildes Bay showed a slow metabolic response to UV radiation after 4 and 8 h of exposure. Copepods from Quintay Bay showed a fast metabolic response after 4 h of exposure （4 orders of magnitude higher than that for Fildes Bay copepods） followed by a rapid return toward baseline after 8 h of exposure. These different responses probably reflect the time the eopepod assemblages have been exposed to increased UV radiation and the extent of adaptive stress responses to cope with that increased UV radiation. The results of this study show that the RNA/DNA ratio is a useful indicator of the physiologic status of marine organisms and is a useful tool to measure the effects of changing environmental conditions on marine ecosystems, such as those associated with global climate change.展开更多
Palm oil is of great potential as one of the sustainable alternatives to fish oil(FO) in aquafeeds.In this present study,five isonitrogenous diets(32% crude protein) with elevated palm oil levels of 0%,2%,4%,6% and 8%...Palm oil is of great potential as one of the sustainable alternatives to fish oil(FO) in aquafeeds.In this present study,five isonitrogenous diets(32% crude protein) with elevated palm oil levels of 0%,2%,4%,6% and 8% were used during an 8-week feeding trial to evaluate its effects on RNA/DNA ratio and lipoprotein lipase(LPL) and Myo D m RNA expressions in muscle of Oreochromis niloticus.The results showed that RNA,DNA content as well as ratio of RNA to DNA were significantly affected(P < 0.05),in each case the highest was recorded in fish group subjected to 6% palm oil level.There was a strong positive correlation between nucleic acid concentration(RNA concentration and RNA:DNA ratio) and specific growth rate(SGR),protein efficiency ratio(PER),while a negative correlation existed between nucleic acid concentration(RNA concentration and RNA:DNA ratio) and feed conversion ratio(FCR).The m RNA expressions of LPL and Myo D in muscle were not significantly affected by the different palm oil levels,although the highest expression was observed in fish fed with 6% palm oil level.There also existed a strong positive correlation between the m RNA expression of LPL,Myo D and SGR,PER,while their correlation with FCR was negative.In conclusion,elevated palm oil affected the RNA,DNA concentration as well as RNA/DNA ratio significantly,although the m RNA expression of LPL and Myo D were not affected significantly by elevated palm oil levels.展开更多
Background: A dandelion is a common plant with a global growth distribution that has been used as a medicinal and food with no adverse effects. Purpose: In this article, the products and effects of dandelions are revi...Background: A dandelion is a common plant with a global growth distribution that has been used as a medicinal and food with no adverse effects. Purpose: In this article, the products and effects of dandelions are reviewed to help further in-depth studies and develop more products derived from dandelions in the future. Method: The literature about dandelion in various databases such as Pubmed is searched. Results: Dandelions have many effects, such as virus inhibition, anti-tumor activity, nutritional value, anti-aging, potential as a vaccine and alleviation of heat stress. The mechanism underlying these effects is analyzed and it was found that dandelions were regulated by RNA or DNA. Conclusion: As a medicinal and food, dandelions are safe and have many effects. Many products derived from dandelions have been developed. The metabolic regulation is related with ribonucleic acid or possibly deoxynucleic acid. Further in-depth studies should be conducted on the regulation of dandelions through RNA or DNA. There will likely be more products derived from dandelions in the future.展开更多
With the help of model experiments, we are able to offer a detailed proposal for the inhibition of DNA duplication and no inhibition of RNA viral infectivity. As a backbone, we introduced methyl phosphotriester (MPTE)...With the help of model experiments, we are able to offer a detailed proposal for the inhibition of DNA duplication and no inhibition of RNA viral infectivity. As a backbone, we introduced methyl phosphotriester (MPTE). Duplex formation according to the traditional Watson and Crick base-pairing: [(MPTE)<sub>n−1</sub> DNA] * DNA and [(MPTE)<sub>n−1</sub> DNA] * RNA, where n = number of DNA and RNA bases. However, in the latter case, inhibition is obtained by reduction of the number of MPTE linkages, as is confirmed with model experiments and under biological conditions with micro (mi)RNA substrates. The latter results have recently been published. One or more single MPTEs are disseminated over different places of DNA without neighbour MPTEs (Prof. Wen-Yih Chen and his group, Taiwan).展开更多
基金supported by the National Natural Science Foundation of China (No.31172085)
文摘The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L （light）： 12D （dark） with lights on at 06：00 and off at 18：00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00：00, 04：00, 08：00, 12：00, 16：00 and 20：00 with 60 turtles each （Initial body weight 88.27 - 0.09 g）. Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate （SGR） and RNA/ DNA：SGR=t.1586RNA/DNA-0.7097 （r = 0.9328, P = 0.0066）. The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12：00 were the lowest from the six groups （P 〈 0.05）. Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight （FBW）, higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total.
文摘The effect of ultraviolet （UV） radiation on marine organisms has been an important focus of recent research, with depletion of the ozone layer resulting in increased UV radiation at high latitudes. Several studies have identified negative impacts of UV radiation on the biology of zooplanktonic organisms. This study used the RNA/DNA ratio as a measure of stress in copepod assemblages from Fildes Bay in Antarctica and Quintay Bay on the central coast of Chile, two areas with high UV radiation but different photobiologic histories. Controlled time-light experiments were performed with copepods from the two locations, exposing them to white light, UV light, or darkness. The results showed different responses to UV radiation. Copepods from Fildes Bay showed a slow metabolic response to UV radiation after 4 and 8 h of exposure. Copepods from Quintay Bay showed a fast metabolic response after 4 h of exposure （4 orders of magnitude higher than that for Fildes Bay copepods） followed by a rapid return toward baseline after 8 h of exposure. These different responses probably reflect the time the eopepod assemblages have been exposed to increased UV radiation and the extent of adaptive stress responses to cope with that increased UV radiation. The results of this study show that the RNA/DNA ratio is a useful indicator of the physiologic status of marine organisms and is a useful tool to measure the effects of changing environmental conditions on marine ecosystems, such as those associated with global climate change.
基金supported by China Agriculture Research System (CARS-49)Shanghai Collaborative Innovation Center for Aquatic Animal Genetics and Breeding (ZF1206)
文摘Palm oil is of great potential as one of the sustainable alternatives to fish oil(FO) in aquafeeds.In this present study,five isonitrogenous diets(32% crude protein) with elevated palm oil levels of 0%,2%,4%,6% and 8% were used during an 8-week feeding trial to evaluate its effects on RNA/DNA ratio and lipoprotein lipase(LPL) and Myo D m RNA expressions in muscle of Oreochromis niloticus.The results showed that RNA,DNA content as well as ratio of RNA to DNA were significantly affected(P < 0.05),in each case the highest was recorded in fish group subjected to 6% palm oil level.There was a strong positive correlation between nucleic acid concentration(RNA concentration and RNA:DNA ratio) and specific growth rate(SGR),protein efficiency ratio(PER),while a negative correlation existed between nucleic acid concentration(RNA concentration and RNA:DNA ratio) and feed conversion ratio(FCR).The m RNA expressions of LPL and Myo D in muscle were not significantly affected by the different palm oil levels,although the highest expression was observed in fish fed with 6% palm oil level.There also existed a strong positive correlation between the m RNA expression of LPL,Myo D and SGR,PER,while their correlation with FCR was negative.In conclusion,elevated palm oil affected the RNA,DNA concentration as well as RNA/DNA ratio significantly,although the m RNA expression of LPL and Myo D were not affected significantly by elevated palm oil levels.
文摘Background: A dandelion is a common plant with a global growth distribution that has been used as a medicinal and food with no adverse effects. Purpose: In this article, the products and effects of dandelions are reviewed to help further in-depth studies and develop more products derived from dandelions in the future. Method: The literature about dandelion in various databases such as Pubmed is searched. Results: Dandelions have many effects, such as virus inhibition, anti-tumor activity, nutritional value, anti-aging, potential as a vaccine and alleviation of heat stress. The mechanism underlying these effects is analyzed and it was found that dandelions were regulated by RNA or DNA. Conclusion: As a medicinal and food, dandelions are safe and have many effects. Many products derived from dandelions have been developed. The metabolic regulation is related with ribonucleic acid or possibly deoxynucleic acid. Further in-depth studies should be conducted on the regulation of dandelions through RNA or DNA. There will likely be more products derived from dandelions in the future.
文摘With the help of model experiments, we are able to offer a detailed proposal for the inhibition of DNA duplication and no inhibition of RNA viral infectivity. As a backbone, we introduced methyl phosphotriester (MPTE). Duplex formation according to the traditional Watson and Crick base-pairing: [(MPTE)<sub>n−1</sub> DNA] * DNA and [(MPTE)<sub>n−1</sub> DNA] * RNA, where n = number of DNA and RNA bases. However, in the latter case, inhibition is obtained by reduction of the number of MPTE linkages, as is confirmed with model experiments and under biological conditions with micro (mi)RNA substrates. The latter results have recently been published. One or more single MPTEs are disseminated over different places of DNA without neighbour MPTEs (Prof. Wen-Yih Chen and his group, Taiwan).
