人工控制条件下生长的小麦、玉米分别培养在含0、0.5、1.0和2.0mM SO_4^(-2)4个硫营养水平的Hoagland 培养液中,对2—6周龄的植株进行了 RuBPCase、PEPCase、NR 的活性,叶片可溶性蛋白质含量,叶绿素 a 和 b 含量以及植株最终叶面积和总...人工控制条件下生长的小麦、玉米分别培养在含0、0.5、1.0和2.0mM SO_4^(-2)4个硫营养水平的Hoagland 培养液中,对2—6周龄的植株进行了 RuBPCase、PEPCase、NR 的活性,叶片可溶性蛋白质含量,叶绿素 a 和 b 含量以及植株最终叶面积和总干重的测定。结果指出,硫营养不足影响了作物的碳、氮代谢,随着供硫量的增加,上述各参数值均得到了有利于植物生长发育的改善,说明一定量的硫营养是氮代谢所必需的,硫对碳代谢的影响恐怕是与其对蛋白质和酶的影响相联系的。展开更多
AIM:To investigate the effect of early enteral nutrition(EEN)combined with parenteral nutritional support in patients undergoing pancreaticoduodenectomy(PD).METHODS:From January 2006,all patients were given EEN combin...AIM:To investigate the effect of early enteral nutrition(EEN)combined with parenteral nutritional support in patients undergoing pancreaticoduodenectomy(PD).METHODS:From January 2006,all patients were given EEN combined with parenteral nutrition(PN)(EEN/PN group,n=107),while patients prior to this date were given total parenteral nutrition(TPN)(TPN group,n=67).Venous blood samples were obtained for a nutrition-associated assessment and liver function tests on the day before surgery and 6 d after surgery.The assessment of clinical outcome was based on postoperative complications.Follow-up for infectious and noninfectious complications was carried out for 30 d after hospital discharge.Readmission within 30 d afterdischarge was also recorded.RESULTS:Compared with the TPN group,a significant decrease in prealbumin(PAB)(P=0.023)was seen in the EEN/PN group.Total bilirubin(TB),direct bilirubin(DB)and lactate dehydrogenase(LDH)were significantly decreased on day 6 in the EEN/PN group(P=0.006,0.004 and 0.032,respectively).The rate of gradeⅠcomplications,gradeⅡcomplications and the length of postoperative hospital stay in the EEN/PN group were significantly decreased(P=0.036,0.028and 0.021,respectively),and no hospital mortality was observed in our study.Compared with the TPN group(58.2%),the rate of infectious complications in the EEN/PN group(39.3%)was significantly decreased(P=0.042).Eleven cases of delayed gastric emptying were noted in the TPN group,and 6 cases in the EEN/PN group.The rate of delayed gastric emptying and hyperglycemia was significantly reduced in the EEN/PN group(P=0.031 and P=0.040,respectively).CONCLUSION:Early enteral combined with PN can greatly improve liver function,reduce infectious complications and delayed gastric emptying,and shorten postoperative hospital stay in patients undergoing PD.展开更多
Severe burn causes significant metabolic derangements that make nutritional support uniquely important and challenging for burned patients. Burn injury causes a persistent and prolonged hypermetabolic state and increa...Severe burn causes significant metabolic derangements that make nutritional support uniquely important and challenging for burned patients. Burn injury causes a persistent and prolonged hypermetabolic state and increased catabolism that results in increased muscle wasting and cachexia. Metabolic rates of burn patients can surpass twice normal, and failure to fulfill these energy requirements causes impaired wound healing, organ dysfunction,and susceptibility to infection. Adequate assessment and provision of nutritional needs is imperative to care for these patients. There is no consensus regarding the optimal timing, route, amount, and composition of nutritional support for burn patients, but most clinicians advocate for early enteral nutrition with highcarbohydrate formulas.Nutritional support must be individualized, monitored, and adjusted throughout recovery. Further investigation is needed regarding optimal nutritional support and accurate nutritional endpoints and goals.展开更多
Amino acids are building blocks for proteins in all animals. Based on growth or nitrogen balance, amino acids were traditionally classified as nutritionally essential or nonessential for mammals, birds and fish. It wa...Amino acids are building blocks for proteins in all animals. Based on growth or nitrogen balance, amino acids were traditionally classified as nutritionally essential or nonessential for mammals, birds and fish. It was assumed that all the ＂nutritionally nonessential amino acids （NEAA）＂ were synthesized sufficiently in the body to meet the needs for maximal growth and optimal health. However, careful analysis of the scientific literature reveals that over the past century there has not been compelling experimental evidence to support this assumption. NEAA （e.g., glutamine, glutamate, proline, glycine and arginine） play important roles in regulating gene expression, cell signaling, antioxidative responses, fertility, neurotransmission, and immunity. Additionally, glutamate, glutamine and aspartate are major metabolic fuels for the small intestine to maintain its digestive function and to protect the integrity of the intestinal mucosa. Thus, diets for animals must contain all NEAA to optimize their survival, growth, development, reproduction, and health. Furthermore, NEAA should be taken into consideration in revising the ＂ideal protein＂ concept that is currently used to formulate swine and poultry diets. Adequate provision of all amino acids （including NEAA） in diets enhances the efficiency of animal production. In this regard, amino acids should not be classified as nutritionally essential or nonessential in animal or human nutrition. The new Texas A＆M University＇s optimal ratios of dietary amino acids for swine and chickens are expected to beneficially reduce dietary protein content and improve the efficiency of their nutrient utilization, growth, and production performance.展开更多
Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of p...Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of pigs to improve their protein nutrition and reduce the costs of pork production. Due to incomplete knowledge of amino acid biochemistry and nutrition, it was traditionally assumed that neonatal, post-weaning, growing-finishing, and gestating pigs could synthesize sufficient amounts of all ＂nutritionally nonessential amino acids＂ （NEAA） to support maximum production performance. Therefore, over the past 50 years, much emphasis has been placed on dietary requirements of nutritionally essential amino acids as building blocks for tissue proteins. However, a large body of literature shows that NEAA, particularly glutamine, glutamate, arginine and proline regulate physiological functions via cell signaling pathways, such as mammalian target of rapamycin, AMP-activated protein kinase, extracellular signal-related kinase, Jun kinase, mitogen-activated protein kinase, and NEAA-derived gaseous molecules （e.g., nitric oxide, carbon monoxide, and hydrogen sulfide）. Available evidence shows that under current feeding programs, only 70% and 55% of dietary amino acids are deposited as tissue proteins in 14-day-old sow-reared piglets and in 30-day-old pigs weaned at 21 days of age, respectively. Therefore, there is an urgent need to understand the robes and dietary requirements of NEAA in swine nutrition. This review highlights the basic biochemistry and physiology of absorption and utilization of amino acids in young pigs to enhance the efficacy of utilization of dietary protein and to minimize excretion of nitrogenous wastes from the body.展开更多
Neonatal osteopenia is an important area of interest for neonatologists due to continuing increased survival of preterm infants. It can occur in high-risk infants such as preterm infants, infants on long-term diuretic...Neonatal osteopenia is an important area of interest for neonatologists due to continuing increased survival of preterm infants. It can occur in high-risk infants such as preterm infants, infants on long-term diuretics or corticosteroids, and those with neuromuscular disorders. Complications such as rickets, pathological fractures, impaired respiratory function and poor growth in childhood can develop and may be the first clinical evidence of the condition. It is important for neonatologists managing such high-risk patients to regularly monitor biochemical markers for evidence of abnormal bone turnover and inadequate mineral intake in order to detect the early phases of impaired bone mineralization. Dual-energy X-ray absorptiometry has become an increasingly used research tool for assessing bone mineral density in children and neonates, but more studies are still needed before it can be used as a useful clinical tool. Prevention and early detection of osteopenia are key to the successful management of this condition and oral phosphate supplements should be started as soon as is feasible.展开更多
文摘人工控制条件下生长的小麦、玉米分别培养在含0、0.5、1.0和2.0mM SO_4^(-2)4个硫营养水平的Hoagland 培养液中,对2—6周龄的植株进行了 RuBPCase、PEPCase、NR 的活性,叶片可溶性蛋白质含量,叶绿素 a 和 b 含量以及植株最终叶面积和总干重的测定。结果指出,硫营养不足影响了作物的碳、氮代谢,随着供硫量的增加,上述各参数值均得到了有利于植物生长发育的改善,说明一定量的硫营养是氮代谢所必需的,硫对碳代谢的影响恐怕是与其对蛋白质和酶的影响相联系的。
基金Supported by Grants from Jiangsu Provincial GovernmentChinaNo.ZX200605
文摘AIM:To investigate the effect of early enteral nutrition(EEN)combined with parenteral nutritional support in patients undergoing pancreaticoduodenectomy(PD).METHODS:From January 2006,all patients were given EEN combined with parenteral nutrition(PN)(EEN/PN group,n=107),while patients prior to this date were given total parenteral nutrition(TPN)(TPN group,n=67).Venous blood samples were obtained for a nutrition-associated assessment and liver function tests on the day before surgery and 6 d after surgery.The assessment of clinical outcome was based on postoperative complications.Follow-up for infectious and noninfectious complications was carried out for 30 d after hospital discharge.Readmission within 30 d afterdischarge was also recorded.RESULTS:Compared with the TPN group,a significant decrease in prealbumin(PAB)(P=0.023)was seen in the EEN/PN group.Total bilirubin(TB),direct bilirubin(DB)and lactate dehydrogenase(LDH)were significantly decreased on day 6 in the EEN/PN group(P=0.006,0.004 and 0.032,respectively).The rate of gradeⅠcomplications,gradeⅡcomplications and the length of postoperative hospital stay in the EEN/PN group were significantly decreased(P=0.036,0.028and 0.021,respectively),and no hospital mortality was observed in our study.Compared with the TPN group(58.2%),the rate of infectious complications in the EEN/PN group(39.3%)was significantly decreased(P=0.042).Eleven cases of delayed gastric emptying were noted in the TPN group,and 6 cases in the EEN/PN group.The rate of delayed gastric emptying and hyperglycemia was significantly reduced in the EEN/PN group(P=0.031 and P=0.040,respectively).CONCLUSION:Early enteral combined with PN can greatly improve liver function,reduce infectious complications and delayed gastric emptying,and shorten postoperative hospital stay in patients undergoing PD.
文摘Severe burn causes significant metabolic derangements that make nutritional support uniquely important and challenging for burned patients. Burn injury causes a persistent and prolonged hypermetabolic state and increased catabolism that results in increased muscle wasting and cachexia. Metabolic rates of burn patients can surpass twice normal, and failure to fulfill these energy requirements causes impaired wound healing, organ dysfunction,and susceptibility to infection. Adequate assessment and provision of nutritional needs is imperative to care for these patients. There is no consensus regarding the optimal timing, route, amount, and composition of nutritional support for burn patients, but most clinicians advocate for early enteral nutrition with highcarbohydrate formulas.Nutritional support must be individualized, monitored, and adjusted throughout recovery. Further investigation is needed regarding optimal nutritional support and accurate nutritional endpoints and goals.
基金supported by National Research Initiative Competitive Grants from the Animal Reproduction Program(2008-35203-19120 and 2011-67015-20028)Animal Growth&Nutrient Utilization Program(2008-35206-18764, 2008-35206-18762,2009-35206-05211,and 2014-67015-21770) of the USDA National Institute of Food and Agriculture Texas A&M AgriLife Research(H-8200),Ajinomoto Inc.(Tokyo,Japan),and Gentech Inc. (Shanghai,China)
文摘Amino acids are building blocks for proteins in all animals. Based on growth or nitrogen balance, amino acids were traditionally classified as nutritionally essential or nonessential for mammals, birds and fish. It was assumed that all the ＂nutritionally nonessential amino acids （NEAA）＂ were synthesized sufficiently in the body to meet the needs for maximal growth and optimal health. However, careful analysis of the scientific literature reveals that over the past century there has not been compelling experimental evidence to support this assumption. NEAA （e.g., glutamine, glutamate, proline, glycine and arginine） play important roles in regulating gene expression, cell signaling, antioxidative responses, fertility, neurotransmission, and immunity. Additionally, glutamate, glutamine and aspartate are major metabolic fuels for the small intestine to maintain its digestive function and to protect the integrity of the intestinal mucosa. Thus, diets for animals must contain all NEAA to optimize their survival, growth, development, reproduction, and health. Furthermore, NEAA should be taken into consideration in revising the ＂ideal protein＂ concept that is currently used to formulate swine and poultry diets. Adequate provision of all amino acids （including NEAA） in diets enhances the efficiency of animal production. In this regard, amino acids should not be classified as nutritionally essential or nonessential in animal or human nutrition. The new Texas A＆M University＇s optimal ratios of dietary amino acids for swine and chickens are expected to beneficially reduce dietary protein content and improve the efficiency of their nutrient utilization, growth, and production performance.
基金supported by National Research Initiative Competitive Grants from the Animal Reproduction Program(2008-35203-19120)Animal Growth&Nutrient Utilization Program(2008-35206-18764)of the USDA National Institute of Food and Agriculture+6 种基金AHA(10GRNT4480020)Texas A&M AgriLife Research(H-8200)the National Basic Research Program of China(2013CB127302)the National Natural Science Foundation of China(30810103902,30972156,31172217,31272450,and 31272451)China Postdoctoral Science Foundation(2012T50163)Chinese Universities Scientific Funds(2012RC024)the Thousand-People Talent program at China Agricultural University
文摘Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of pigs to improve their protein nutrition and reduce the costs of pork production. Due to incomplete knowledge of amino acid biochemistry and nutrition, it was traditionally assumed that neonatal, post-weaning, growing-finishing, and gestating pigs could synthesize sufficient amounts of all ＂nutritionally nonessential amino acids＂ （NEAA） to support maximum production performance. Therefore, over the past 50 years, much emphasis has been placed on dietary requirements of nutritionally essential amino acids as building blocks for tissue proteins. However, a large body of literature shows that NEAA, particularly glutamine, glutamate, arginine and proline regulate physiological functions via cell signaling pathways, such as mammalian target of rapamycin, AMP-activated protein kinase, extracellular signal-related kinase, Jun kinase, mitogen-activated protein kinase, and NEAA-derived gaseous molecules （e.g., nitric oxide, carbon monoxide, and hydrogen sulfide）. Available evidence shows that under current feeding programs, only 70% and 55% of dietary amino acids are deposited as tissue proteins in 14-day-old sow-reared piglets and in 30-day-old pigs weaned at 21 days of age, respectively. Therefore, there is an urgent need to understand the robes and dietary requirements of NEAA in swine nutrition. This review highlights the basic biochemistry and physiology of absorption and utilization of amino acids in young pigs to enhance the efficacy of utilization of dietary protein and to minimize excretion of nitrogenous wastes from the body.
文摘Neonatal osteopenia is an important area of interest for neonatologists due to continuing increased survival of preterm infants. It can occur in high-risk infants such as preterm infants, infants on long-term diuretics or corticosteroids, and those with neuromuscular disorders. Complications such as rickets, pathological fractures, impaired respiratory function and poor growth in childhood can develop and may be the first clinical evidence of the condition. It is important for neonatologists managing such high-risk patients to regularly monitor biochemical markers for evidence of abnormal bone turnover and inadequate mineral intake in order to detect the early phases of impaired bone mineralization. Dual-energy X-ray absorptiometry has become an increasingly used research tool for assessing bone mineral density in children and neonates, but more studies are still needed before it can be used as a useful clinical tool. Prevention and early detection of osteopenia are key to the successful management of this condition and oral phosphate supplements should be started as soon as is feasible.
