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Intrinsic processes are assumed to underlie life history expression and trade‐offs, but extrinsic inputs are theorised to shift trait expression and mask trade‐offs within species. Here, we explore application of this theory across species. We do this based on parentally induced embryo temperature as an extrinsic input, and mass‐specific embryo metabolism as an intrinsic process, underlying embryonic development rate. We found that embryonic metabolism followed intrinsic allometry rules among 49 songbird species from temperate and tropical sites. Extrinsic inputs via parentally induced temperatures explained the majority of variation in development rates and masked a relationship with metabolism; metabolism explained a minor proportion of the variation in development rates among species, and only after accounting for temperature effects. We discuss evidence that temperature further obscures the expected interspecific trade‐off between development rate and offspring quality. These results demonstrate the importance of considering extrinsic inputs to trait expression and trade‐offs across species. 相似文献
84.
分泌型磷脂酶PLA2G5属于磷脂酶A2超家族的一员,在免疫细胞和非免疫细胞中均有表达.研究表明,PLA2G5参与生物学事件的发生发展,在特定的病理条件下具有诱导作用.本文简要阐述了PLA2G5的来源、结构特征、生物学功能和在疾病中的作用,以及现有或潜在的PLA2G5抑制剂,以期探索基于PLA2G5的治疗新靶标. 相似文献
85.
《Bioscience, biotechnology, and biochemistry》2013,77(12):2304-2308
The effects of a hot water extract and fractional extracts from rabbiteye blueberry (Vaccinium ashei reade) leaves (BBL) on lipid metabolism were studied in obese Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Feeding the hot water extract and fractional extracts from BBL alleviated hepatic triglyceride accumulation in the rats. Additionally, feeding with the flavonol glycoside (FG) and proanthocyanidin (PA) fractions lowered serum cholesterol levels in the obese rats. The results from measurements of the hepatic enzyme activity indicate that the hypolipidemic effects of the hot water extract and the PA fraction might be attributable to enhanced lipolysis in the liver. The reduced serum levels of C-reactive protein, an inflammatory cytokine, by the chlorogenic acid + rutin fraction and FG fraction might be associated with alleviating the metabolic abnormalities in obese rats. These results indicate that the BBL extracts, and especially FG and PA, exerted hypolipidemic effects on obese OLETF rats and suggest that an infusion of BBL can be useful as a dietary hypolipidemic component. 相似文献
86.
《Bioscience, biotechnology, and biochemistry》2013,77(10):2200-2204
We investigated the dose-effect of the long-term intake of conjugated linoleic acid (CLA) on the energy metabolism and fat accumulation in mice. Five-week-old male Std ddY mice were fed on a diet containing none (control), 0.25%, 0.5% or 1.0% CLA for 4 or 8 weeks. The body weight was lower in the CLA groups than in the control group, and significant differences were detected between the 1.0% CLA group and the control group at both 4 and 8 weeks. The epididymal and perirenal adipose tissue weights were significantly lower in the CLA groups than in the control group. The liver weight and hepatic triglyceride values were higher in the 1.0% CLA group than in the other groups. The metabolic rate was measured after 8 weeks by using a gas analyzer. The oxygen consumption of the mice in the CLA groups was significantly higher than that of the control mice. Since there was a significant effect on the mice supplemented with 0.25% CLA, low concentration of CLA is suggested to suppress the body fat accumulation and increase the energy metabolism. 相似文献
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《Bioscience, biotechnology, and biochemistry》2013,77(11):2598-2603
The oxylipin metabolism was analyzed in soybean homogenates containing different sets of lipoxygenase isozymes (L-1, -2, and -3); namely, Suzuyutaka (containing L-1, -2, and -3), Yumeyutaka (containing only L-1), Kanto102 (containing L-2), Kyushu119 (containing L-3), and Ichihime (lacking all three isozymes). The amount of oxidized fatty acids in the esterified form was higher than that in the free form with every cultivar. Kanto102 formed the highest amount of oxidized lipids, and Yumeyutaka and Ichihime formed the lowest. With Kanto102 and Kyushu119, high amounts of keto fatty acids were formed, while they were undetectable with Yumeyutaka and Ichihime. Due to the lack of lipoxygenases in Ichihime, an accumulation of free fatty acids was expected; however, their amount in Yumeyutaka was significantly lower than was expected. It is suggested that a pathway existed to form C6-volatiles through hydroperoxides in the esterified form. 相似文献
90.
The relationship between excitotoxicity and oxidative stress in the central nervous system 总被引:2,自引:0,他引:2
Excitotoxicity and oxidative stress are two phenomena that have been repeatedly described as being implicated in a wide range of disorders of the nervous system. Such disorders include several common idiopathic neurological diseases, traumatic brain injury, and the consequences of exposure to certain neurotoxic agents. While there is evidence that metabolic derangements can laed to these adverse processes, and that these processes may synergize in their damaging effects, the degree of interdependence, and the causal relation between them is not clear. The intent of this review is to delineate potential mechanisms which may unit hyperexcitation to the excessive generation of reactive oxygen species. The degree of linkage between these events appears rather strong. It is likely that excitoxicity frequency leads to a pro-oxidant condition but that high rates of generation of reactive oxygen species are not invariably accompanied by a hyperexcited neuronal state Both excitoxic and ‘oxidotoxic’ states result from the failure of normal compensatory anti excitatory and antioxidant mechanisms to maintain cellular homeostatis. 相似文献