AIM: To investigate the effect of glutamine (Gln)-containing parenteral nutrition on phagocytic activity and to elucidate the possible roles of Gln in the secretion of anabolic hormones and nitrogen balance in rats un...AIM: To investigate the effect of glutamine (Gln)-containing parenteral nutrition on phagocytic activity and to elucidate the possible roles of Gln in the secretion of anabolic hormones and nitrogen balance in rats undergoing a gastrectomy. METHODS: Rats with an internal jugular catheter were divided into 2 experimental groups and received total parenteral nutrition (TPN). The TPN solutions were isonitrogenous and identical in nutrient compositions except for differences in amino acid content. One group received conventional TPN (control), and in the other group, 25% of the total amino acid nitrogen was replaced with Gin. After receiving TPN for 3 d, one-third of the rats in each experimental group were sacrificed as the baseline group. The remaining rats underwent a partial gastrectomy and were killed 1 and 3 d, respectively, after surgery. Plasma, peritoneal lavage fluid (PLF), and urine samples were collected for further analysis. RESULTS: The Gln group had fewer nitrogen losses 1 and 2 d after surgery (d1, 16.6±242.5 vs-233.4±205.9 mg/d, d2, 31.8±238.8 vs-253.4±184.6 mg/d, P<0.05). There were no differences in plasma growth hormone (GH) and insulin-like growth factor-1 levels between the 2 groups before or after surgery. The phagocytic activity of peritoneal macrophages was higher in the Gln group than in the control group 1 d after surgery (A 1185±931 vs323±201, P<0.05). There were no differences in the phagocytic activities of blood polymorphonuclear neutrophils between the 2 groups at the baseline or on the postoperative days. No significant differences in interleukin-1β or interleukin-6 concentrations in PLF were observed between the 2 groups. However, tumor necrosis factor-α level in PLF was significantly lower in the Gln group than in the control group on postoperative d 3. CONCLUSION: TPN supplemented with Gln can improve the nitrogen balance, and enhance macrophage phagocytic activity at the site of injury. However, Gin supplementation has no effect on phagocytic cell activity in the systemic circulation, GH and insulin-like growth factor-1 might not be responsible for attenuating nitrogen losses in rats with a partial gastrectomy.展开更多
AIM: To investigate the effects of an enteral supple-ment containing antioxidants on circulating levels of antioxidants and indicators of oxidative stress after major gastrointestinal surgery.METHODS: Twenty-one patie...AIM: To investigate the effects of an enteral supple-ment containing antioxidants on circulating levels of antioxidants and indicators of oxidative stress after major gastrointestinal surgery.METHODS: Twenty-one patients undergoing major upper gastrointestinal tract surgery were randomised in a single centre, open label study on the effect of postoperative enteral nutrition supplementedwith antioxidants. The effect on circulating levels of antioxidants and indicators of oxidative stress, such as F2-isoprostane, was studied. RESULTS: The antioxidant enteral supplement showed no adverse effects and was well tolerated. After surgery a decrease in the circulating levels of antioxidant parameters was observed. Only selenium and glutamine levels were restored to pre-operative values one week after surgery. F2-isoprostane increased in the first three postoperative days only in the antioxidant supplemented group. Lipopolysaccharide binding protein (LBP) levels decreased faster in the antioxidant group after surgery.CONCLUSION: Despite lower antioxidant levels there was no increase in the circulating markers of oxidative stress on the first day after major abdominal surgery. The rise in F2-isoprostane in patients receiving the antioxidant supplement may be related to the conversion of antioxidants to oxidants which raises questions on antioxidant supplementation. Module AOX restored the postoperative decrease in selenium levels. The rapid decrease in LBP levels in the antioxidant group suggests a possible protective effect on gut wall integrity. Further studies are needed on the role of oxidative stress on outcome and the use of antioxidants in patients undergoing major abdominal surgery.展开更多
多年来,全球肠外肠内营养学界同道们都在寻求营养不良诊断标准的统一,既需要确定营养不良诊断标准,也需要考虑营养不良指标在不同国家、不同种族的正常值和按临床研究得到的切割点(cut-off point)。全球(营养)领导层倡议营养不良(Global...多年来,全球肠外肠内营养学界同道们都在寻求营养不良诊断标准的统一,既需要确定营养不良诊断标准,也需要考虑营养不良指标在不同国家、不同种族的正常值和按临床研究得到的切割点(cut-off point)。全球(营养)领导层倡议营养不良(Global Leadership Initiative on Malnutrition,GLIM)诊断标准于2018年9月在美国肠外肠内营养学会(American Society for Parenteral and Enteral Nutrition,ASPEN)和欧洲临床营养和代谢学会(European Society for Clinical Nutrition and Metabolism,ESPEN)网站发表。2019年初在纸质版杂志《JPEN》及《Clinical Nutrition》发表。GLIM在《全国科学技术名词审定委员会-肠外肠内营养学分名词-2019》有记载。GLIM中的某些阈值可能会随着时间的推移而有演变,但是从主观评定营养不良(如SGA、PG-SGA),发展到用表现型指标、病因型指标诊断营养不良的方向是正确的。高质量的前瞻性临床有效性验证报告和前瞻性多中心临床应用数据分析,将是GLIM改进的基础。2016年《疾病分类与代码》GB/T(中国ICD-10扩充版)及2019年《关于全国三级公立医院绩效考核通知〔2019〕》以及国家医保局信息业务数据库等三个方面文件均收录了营养风险、营养不良、重度(严重)营养不良作为疾病名称。目前临床各学科都在推行个体化医疗,但是临床各科室的实际情况不同。对肠外肠内营养支持疗法的临床应用来说,与对癌症患者的精准医疗、靶向治疗是有很大的距离。2004年12月,中华医学会肠外肠内营养学分会(Chinese Society for Parenteral and Enteral Nutritional,CSPEN)常委会组建营养风险-不足-营养支持-结局-成本效果比(Nutritional risk-undernutrition-support-outcome-cost effectiveness ratio,NUSOC)多中心分享数据库协作组,该协作组的目标是分出哪些患者需要肠外肠内营养支持疗法,合理应用前提下让患者受益。中国的疾病诊断相关分组(Diagnosis Related Groups,DRG)正在用采集大数据办法来完善DRG(初级阶段DIP,即按病种打包)的制定,就需要让大数据收集系统看到有代码的营养风险和营养不良两个疾病名称,需要填写在出院病案的首页。展开更多
It is a comparatively convenient technique to investigate the motion of a particle with the help of the differential geometry the-ory,rather than directly decomposing the motion in the Cartesian coordinates.The new mo...It is a comparatively convenient technique to investigate the motion of a particle with the help of the differential geometry the-ory,rather than directly decomposing the motion in the Cartesian coordinates.The new model of three-dimensional (3D) guidance problem for interceptors is presented in this paper,based on the classical differential geometry curve theory.Firstly,the kinematical equations of the line of sight (LOS) are gained by carefully investigating the rotation principle of LOS,the kinematic equations of LOS are established,and the concepts of curvature and torsion of LOS are proposed.Simultaneously,the new relative dynamic equations between interceptor and target are constructed.Secondly,it is found that there is an instan-taneous rotation plane of LOS (IRPL) in the space,in which two-dimensional (2D) guidance laws could be constructed to solve 3D interception guidance problems.The spatial 3D true proportional navigation (TPN) guidance law could be directly introduced in IRPL without approximation and linearization for dimension-reduced 2D TPN.In addition,the new series of augmented TPN (APN) and LOS angular acceleration guidance laws (AAG) could also be gained in IRPL.After that,the dif-ferential geometric guidance commands (DGGC) of guidance laws in IRPL are advanced,and we prove that the guidance commands in arc-length system proposed by Chiou and Kuo are just a special case of DGGC.Moreover,the performance of the original guidance laws will be reduced after the differential geometric transformation.At last,an exoatmospheric intercep-tion is taken for simulation to demonstrate the differential geometric modeling proposed in this paper.展开更多
基金Supported by Research Grant from National Science Council,Taipei, Taiwan, China No. 91-2815-C-038-007-B
文摘AIM: To investigate the effect of glutamine (Gln)-containing parenteral nutrition on phagocytic activity and to elucidate the possible roles of Gln in the secretion of anabolic hormones and nitrogen balance in rats undergoing a gastrectomy. METHODS: Rats with an internal jugular catheter were divided into 2 experimental groups and received total parenteral nutrition (TPN). The TPN solutions were isonitrogenous and identical in nutrient compositions except for differences in amino acid content. One group received conventional TPN (control), and in the other group, 25% of the total amino acid nitrogen was replaced with Gin. After receiving TPN for 3 d, one-third of the rats in each experimental group were sacrificed as the baseline group. The remaining rats underwent a partial gastrectomy and were killed 1 and 3 d, respectively, after surgery. Plasma, peritoneal lavage fluid (PLF), and urine samples were collected for further analysis. RESULTS: The Gln group had fewer nitrogen losses 1 and 2 d after surgery (d1, 16.6±242.5 vs-233.4±205.9 mg/d, d2, 31.8±238.8 vs-253.4±184.6 mg/d, P<0.05). There were no differences in plasma growth hormone (GH) and insulin-like growth factor-1 levels between the 2 groups before or after surgery. The phagocytic activity of peritoneal macrophages was higher in the Gln group than in the control group 1 d after surgery (A 1185±931 vs323±201, P<0.05). There were no differences in the phagocytic activities of blood polymorphonuclear neutrophils between the 2 groups at the baseline or on the postoperative days. No significant differences in interleukin-1β or interleukin-6 concentrations in PLF were observed between the 2 groups. However, tumor necrosis factor-α level in PLF was significantly lower in the Gln group than in the control group on postoperative d 3. CONCLUSION: TPN supplemented with Gln can improve the nitrogen balance, and enhance macrophage phagocytic activity at the site of injury. However, Gin supplementation has no effect on phagocytic cell activity in the systemic circulation, GH and insulin-like growth factor-1 might not be responsible for attenuating nitrogen losses in rats with a partial gastrectomy.
文摘AIM: To investigate the effects of an enteral supple-ment containing antioxidants on circulating levels of antioxidants and indicators of oxidative stress after major gastrointestinal surgery.METHODS: Twenty-one patients undergoing major upper gastrointestinal tract surgery were randomised in a single centre, open label study on the effect of postoperative enteral nutrition supplementedwith antioxidants. The effect on circulating levels of antioxidants and indicators of oxidative stress, such as F2-isoprostane, was studied. RESULTS: The antioxidant enteral supplement showed no adverse effects and was well tolerated. After surgery a decrease in the circulating levels of antioxidant parameters was observed. Only selenium and glutamine levels were restored to pre-operative values one week after surgery. F2-isoprostane increased in the first three postoperative days only in the antioxidant supplemented group. Lipopolysaccharide binding protein (LBP) levels decreased faster in the antioxidant group after surgery.CONCLUSION: Despite lower antioxidant levels there was no increase in the circulating markers of oxidative stress on the first day after major abdominal surgery. The rise in F2-isoprostane in patients receiving the antioxidant supplement may be related to the conversion of antioxidants to oxidants which raises questions on antioxidant supplementation. Module AOX restored the postoperative decrease in selenium levels. The rapid decrease in LBP levels in the antioxidant group suggests a possible protective effect on gut wall integrity. Further studies are needed on the role of oxidative stress on outcome and the use of antioxidants in patients undergoing major abdominal surgery.
文摘多年来,全球肠外肠内营养学界同道们都在寻求营养不良诊断标准的统一,既需要确定营养不良诊断标准,也需要考虑营养不良指标在不同国家、不同种族的正常值和按临床研究得到的切割点(cut-off point)。全球(营养)领导层倡议营养不良(Global Leadership Initiative on Malnutrition,GLIM)诊断标准于2018年9月在美国肠外肠内营养学会(American Society for Parenteral and Enteral Nutrition,ASPEN)和欧洲临床营养和代谢学会(European Society for Clinical Nutrition and Metabolism,ESPEN)网站发表。2019年初在纸质版杂志《JPEN》及《Clinical Nutrition》发表。GLIM在《全国科学技术名词审定委员会-肠外肠内营养学分名词-2019》有记载。GLIM中的某些阈值可能会随着时间的推移而有演变,但是从主观评定营养不良(如SGA、PG-SGA),发展到用表现型指标、病因型指标诊断营养不良的方向是正确的。高质量的前瞻性临床有效性验证报告和前瞻性多中心临床应用数据分析,将是GLIM改进的基础。2016年《疾病分类与代码》GB/T(中国ICD-10扩充版)及2019年《关于全国三级公立医院绩效考核通知〔2019〕》以及国家医保局信息业务数据库等三个方面文件均收录了营养风险、营养不良、重度(严重)营养不良作为疾病名称。目前临床各学科都在推行个体化医疗,但是临床各科室的实际情况不同。对肠外肠内营养支持疗法的临床应用来说,与对癌症患者的精准医疗、靶向治疗是有很大的距离。2004年12月,中华医学会肠外肠内营养学分会(Chinese Society for Parenteral and Enteral Nutritional,CSPEN)常委会组建营养风险-不足-营养支持-结局-成本效果比(Nutritional risk-undernutrition-support-outcome-cost effectiveness ratio,NUSOC)多中心分享数据库协作组,该协作组的目标是分出哪些患者需要肠外肠内营养支持疗法,合理应用前提下让患者受益。中国的疾病诊断相关分组(Diagnosis Related Groups,DRG)正在用采集大数据办法来完善DRG(初级阶段DIP,即按病种打包)的制定,就需要让大数据收集系统看到有代码的营养风险和营养不良两个疾病名称,需要填写在出院病案的首页。
文摘It is a comparatively convenient technique to investigate the motion of a particle with the help of the differential geometry the-ory,rather than directly decomposing the motion in the Cartesian coordinates.The new model of three-dimensional (3D) guidance problem for interceptors is presented in this paper,based on the classical differential geometry curve theory.Firstly,the kinematical equations of the line of sight (LOS) are gained by carefully investigating the rotation principle of LOS,the kinematic equations of LOS are established,and the concepts of curvature and torsion of LOS are proposed.Simultaneously,the new relative dynamic equations between interceptor and target are constructed.Secondly,it is found that there is an instan-taneous rotation plane of LOS (IRPL) in the space,in which two-dimensional (2D) guidance laws could be constructed to solve 3D interception guidance problems.The spatial 3D true proportional navigation (TPN) guidance law could be directly introduced in IRPL without approximation and linearization for dimension-reduced 2D TPN.In addition,the new series of augmented TPN (APN) and LOS angular acceleration guidance laws (AAG) could also be gained in IRPL.After that,the dif-ferential geometric guidance commands (DGGC) of guidance laws in IRPL are advanced,and we prove that the guidance commands in arc-length system proposed by Chiou and Kuo are just a special case of DGGC.Moreover,the performance of the original guidance laws will be reduced after the differential geometric transformation.At last,an exoatmospheric intercep-tion is taken for simulation to demonstrate the differential geometric modeling proposed in this paper.
