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51.
Background: The rapid gain in lean mass in neonates requires greater rates of protein synthesis than degradation. We previously delineated the molecular mechanisms by which insulin and amino acids, especially leucine, modulate skeletal muscle protein synthesis and how this changes with development. In the current study, we identified mechanisms involved in protein degradation regulation. In experiment 1,6- and 26-d-old pigs were studied during 1) euinsulinemic-euglycemic-euaminoacidemic, 2) euinsulinemic-euglycemiohyperaminoacidemic, and 3) hyperinsulinemic-euglycemic-euaminoacidemic clamps for 2 h. In experiment 2, 5-d-old pigs were studied during 1) euinsulinemic-euglycemic-euaminoacidemic-euleucinemic, 2) euinsulinemic-euglycemic-hypoaminoacidemic- hyperleucinemic, and 3) euinsulinemic-euglycemic-euaminoacidemic-hyperleucinemic clamps for 24 h. We determined in muscle indices of ubiquitin-proteasome, i.e., atrogin-1 (MAFbx) and muscle RING-finger protein-1 (MuRF1) and autophagy-lysosome systems, i.e., unc51-1ike kinase 1 (UKL1), microtubule-associated protein light chain 3 (LC3), and lysosomal-associated membrane protein 2 (Lamp-2). For comparison, we measured ribosomal protein 56 (rpS6) and eukaryotic initiation factor 4E (elF4E) activation, components of translation initiation. Results: Abundance of atrogin-1, but not MuRF1, was greater in 26- than 6-d-old pigs and was not affected by insulin, amino acids, or leucine. Abundance of ULK1 and LC3 was higher in younger pigs and not affected by treatment. The LC3-11/LC3-1 ratio was reduced and ULK1 phosphorylation increased by insulin, amino acids, and leucine. These responses were more profound in younger pigs. Abundance of Lamp-2 was not affected by treatment or development. Abundance of elF4E, but not rpS6, was higher in 6- than 26-d-old-pigs but unaffected by treatment. Phosphorylation of elF4E was not affected by treatment, however, insulin, amino acids, and leucine stimulated rpS6 phosphorylation, and the response  相似文献   
52.
Industrial and urban developments in Indonesia focus on the economic merits, but neglect agricultural services that, when disappear, will destabilize the environmental and livelihood systems. A series of 5-year study has evaluated various aspects of multifunctionality and implications of paddy field conversion on the disappearance of multifunctionality. Soil loss from a series of 18 terraced paddy fields in central Java is negligible. Only a few terraces located along the streams directly caused sedimentation. The functions of flood mitigation, water-resource conservation, erosion reduction, organic waste disposal, heat mitigation, and rural amenity of paddy fields in Citarum watershed in West Java were significant. The ‘replacement costs’ of such functions was about 51% ($92.67 million yr−1) of the total price of rice of $181.34 million yr−1 produced in the 156,000 ha paddy field. This amount could be considered as free services by the farmers to the society. However, because of society's negligence and unawareness, conversion has been accelerating while development of new paddy fields has been decelerating in the last few years. Low and fluctuating price of agricultural products, unavailability or non-affordability of agricultural supplies and inaccessibility to market are among the major disincentives faced by farmers. Because of appreciable multifunctionality they produce, farmers deserve various incentives for the sake of environmental sustainability and other services.  相似文献   
53.
An experiment was conducted to study the effect of supplementing catfish (Pangasianodon hypophthalmus) with turmeric (Curcuma longa) on the vitellogenic capacity of the liver as a new method to improve reproductive performance in oviparous animals. The experimental catfish were assigned to a completely randomized design consisting of four doses of supplemental turmeric (0, 1.2, 2.4 and 4.8 g/kg feed) with 10 catfish with body weights ranging from 2 to 4 kg in each group. Blood samples were collected on days 0, 14, 28, 42 and 56 of turmeric supplementation to measure the concentrations of plasma oestradiol‐17ß and vitellogenin. The weights of the body, gonads and liver were measured on days 0, 28 and 56. The fecundities of the catfish were measured on days 28 and 56 of turmeric supplementation, and egg diameters were measured on days 28 and 42. The results showed that catfish supplemented with turmeric at a dose of 2.4 or 4.8 g/kg feed had higher growth rates, higher plasma oestradiol‐17β and vitellogenin concentrations, and higher gonad somatic index values and egg diameters. This is the first report demonstrating that the hepatoprotective activity of the curcumin in turmeric could be used to improve both vitellogenin synthesis, which improves nutrient deposition in the ovulating eggs, and the reproductive performance of teleost fish and oviparous animals.  相似文献   
54.
The aim of this research was to identify the changes in the cytoplasmic ultrastructure of immature and matured oocytes in buffalo (Bubalus bubalis ). Oocytes were matured in vitro in tissue culture medium?199 with and without sericin, and then analyzed by light and transmission electron microscopy. The experiment result showed that the nuclear maturation rate of buffalo oocytes was significantly higher in the presence of sericin (80.6%) than without sericin (68.1%) (P  < 0.05). The immature oocytes were characterized by cortical granule clusters in the ooplasm and the absence of perivitelline space (PVS ). In contrast, the oocytes matured either with or without sericin showed the formation of PVS , erected microvilli, the migration of cortical granules to the cytoplasmic periphery, and the clear appearance of the mitochondria and vesicle in the oolemma. Interestingly, matured oocytes with sericin have smaller cortical granules than do immature oocytes (P  < 0.05). In conclusion, supplementation of 0.05% sericin in the maturation medium can enhance the maturation rate of buffalo oocytes. Several cytoplasmic ultrastructures were relocated and modulated during the in vitro maturation process of buffalo oocytes: PVS development, cortical granules migration to periphery, and mitochondria and vesicles in the cortical region. The ultrastructure was similar between the groups with and without sericin.  相似文献   
55.
Smallholder timber plantations may offer opportunities for farmers to increase their income. Nonetheless, such opportunities are often lost largely due to unfavorable regulations imposed on harvesting and marketing of timber. Adverse impacts are worsened because the regulations are not effectively communicated to smallholder farmers. We assessed the level of smallholder knowledge of existing regulations and found it very low. In part, this correlated to their socio-demographic characteristics. Poor literacy skills and a low level of education make it difficult for older farmers’ to increase their knowledge. This is compounded by the limited information channels that can reach the farmers. Improving smallholders’ knowledge by providing information concerning markets and regulations in a timely and clear manner could help smallholders exercise coping strategies and priorities when selling their timber that would in turn reduce the negative impacts of regulations. The roles of village authorities could be crucial. They are close to the smallholders and could channel the information. The government could provide training and incentives for them to be more active in communicating the regulations to the smallholders.  相似文献   
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