Metabolism of glutamine in lymphocytes.

Pathways of glutamine metabolism in resting and proliferating rat thymocytes and established human T- and B-lymphoblastoid cell lines were evaluated by in vitro incubations of freshly prepared or cultured cells for one to two hours with [U14C]glutamine. Complete recovery of glutamine carbons utilized in products allowed quantification of the pathways of glutamine metabolism under the experimental conditions. Partial oxidation of glutamine via 2-oxoglutarate in a truncated citric acid cycle to CO2 and oxaloacetate, which then was converted to aspartate, accounted for 76% and 69%, respectively, of the glutamine metabolized beyond the stage of glutamate by resting and proliferating thymocytes.

Nitrogen absorption in pancreatectomized patients: protein versus protein hydrolysate as substrate.

To investigate nitrogen absorption in the absence of the pancreas, six patients with total pancreatectomy, all in stable nutritional and metabolic condition, underwent two periods of enteral nutrition identical in all respects except for the nitrogen source. Nitrogen source was either lactalbumin or its hydrolysate. The quantity and quality of calories infused simulated the patient's usual diet, which was a high-protein diet (2.

[Pathophysiology of post-aggression metabolism].

The metabolic situation of the socalled "post aggression syndrome" related to operations or trauma is elucidated in terms of two out of three phases described by a working hypothesis. It is governed primarily by anti insulin factors and can be identified by the resulting catabolism. The leading phenomena are increased of general turnover rates, glycogenolysis, gluconeogenesis, lipolysis, and protein degradation.

Influence of two glutamine-containing dipeptides on growth of mammalian cells.

The instability of the amino acid glutamine prompted us to investigate substitute compounds appropriate for culture conditions. The effect of two glutamine-containing dipeptides, alanylglutamine (Ala-Gln) and glycylglutamine (Gly-Gln), on the growth behavior of a hematopoietic cell line in culture (K562) was investigated. Growth rates and [3H]thymidine incorporation rates of cells cultivated in sterile-filtrated media, containing glutamine (Gln) or Ala-Gln or Gly-Gln, were not statistically different.

Plasma amino and keto acids in chronic renal failure.

During both early and late stages of chronic renal insufficiency the response of BCKA to the disease state, as indicated by plasma levels, differs from that of BCAA. Val is the only BCAA whose concentration changes under the conditions of our study, and this only during the more advanced stages of disease. In contrast, all three BCKA declined, KIVA and KICA even in mild renal failure, showing that already during the early stages of the disease these BCKA levels are decreased.

Pathways of glutamine and glutamate metabolism in resting and proliferating rat thymocytes: comparison between free and peptide-bound glutamine.

Pathways of glutamine metabolism in resting and proliferating rat thymocytes were evaluated by in vitro incubations of freshly prepared or 60-h cultured cells for 1-2 h with [U14C]glutamine. Complete recovery of glutamine carbons utilized in products allowed quantification of the pathways of glutamine metabolism under the experimental conditions. Partial oxidation of glutamine via 2-oxoglutarate in a truncated citric acid cycle to CO2 and oxaloacetate, which then was converted to aspartate, accounted for 76 and 69%, respectively, of the glutamine metabolized beyond the stage of glutamate by resting and proliferating thymocytes.

[Metabolism-oriented postoperative nutritional therapy--possibilities and limits in the use of glucose and xylitol].

Carbohydrates and polyols are essential constituents of intravenous nutrition. In order to better understand the problems associated with the supply of energy sources, the physiology of enteral nutrition will be covered and compared with intravenous nutrition. This review article will deal with the metabolic actions of glucose and xylitol and derive therapeutical consequences for their intravenous use during different illnesses.

Parenteral nutrition with an amino acid solution containing a mixture of dipeptides. Evidence for efficient utilization of dipeptides in man.

Ten healthy human subjects received parenteral nutrition consisting of 80 g of a dipeptide-amino acid mixture and 900 carbohydrate calories infused over a period of 12 h, and then fasted for another period of 12 h. The dipeptides included in the mixture were: glycyl-L-glutamine, glycyl-L-tyrosine, glycyl-L-leucine, glycyl-L-isoleucine, and glycyl-L-valine. Parenteral nutrition with the dipeptide-amino acid mixture was without any adverse reaction in any of the subjects.

Protein nutrition and amino acid metabolism after 4 weeks of total parenteral nutrition with a mixture of 14 dipeptides: serendipitous observations on effects of sepsis in baboons.

We investigated parameters of nutrition, metabolism, and organ function after 4 wk of total parenteral nutrition (TPN) in baboons receiving either dipeptides or amino acids as the nitrogen source. The two groups showed no significant difference with respect to gain in body weight, nitrogen balance, plasma and muscle concentrations of amino acids, plasma concentrations of proteins, and leucine incorporation into muscle protein. All dipeptides were efficiently utilized as evidenced by trace concentrations of dipeptides in plasma and urine; they produced no deleterious effect on the function of liver, kidney, or immune system.

[Imbalances of neutral plasma amino acids as a pathogenetic factor in anorexia].

Studies in anorectic tumor-bearing rats indicate that anorexia is correlated to imbalances of neutral amino acids in blood and CNS. Consequently plasma amino acids of patients with neoplastic and non-neoplastic internal diseases were studied during phases of anorexia; special regard was given to the precursors of dopamine and serotonin. Anorectic patients were compared to non-anorectic patients with neoplasia.

Efficacy of a synthetic dipeptide mixture as the source of amino acids for total parenteral nutrition in a subhuman primate (baboon). Plasma concentration, metabolic clearance, and urinary excretion of a series of dipeptides.

To assess the efficacy and safety of oligopeptides as substrates for total parenteral nutrition, we investigated the effects of intravenous infusion of a synthetic dipeptide mixture, as compared with a corresponding amino acid mixture, on a range of parameters of nutrition, metabolism, and organ function in baboons. In all respects the two periods of total parenteral nutrition, each lasting for 1 wk, were identical except for the difference between the forms of amino acids in the parenteral solutions, being in free form in one period and in dipeptide form in the other. The dipeptide mixture was composed of a series of 12 dipeptides each containing glycine in the N-terminal position and either an essential or nonessential amino acid in the carboxyl position.

The effect of L-carnitine-supplemented total parenteral nutrition on tissue amino acid concentrations in piglets.

Miniature piglets underwent total parenteral nutrition (TPN) with and without L-carnitine supplementation during a 7-day period. Thereafter the tissue amino acid concentrations of liver, heart, skeletal muscle and brain were determined and compared to those of orally fed animals. The altered tissue amino acid concentrations during TPN without carnitine returned to normal when L-carnitine was supplemented.

Improved N-retention during L-carnitine-supplemented total parenteral nutrition.

The influence of intravenously administered L-carnitine on lipid- and nitrogen-metabolism was studied during total parenteral nutrition of piglets (mean weight 4077 g; n = 9). The infusion protocol was divided into three isocaloric and isonitrogenous 48-hr periods. Amino acids (3 g/kg day) were administered throughout all three periods: 140 cal/kg/day were given as nonprotein calories, consisting only of glucose during period 1; during periods 2 and 3, an amount of glucose calorically equivalent to 4 g fat/kg/day was substituted with a lipid emulsion, and L-carnitine (1.

Tissue carnitine concentrations after total parenteral nutrition with and without L-carnitine supplementation.

The concentrations (mumoles/g dry weight) of total carnitine (TC), free carnitine (FC) and acylcarnitine (AC) were determined in skeletal muscle, heart, liver, kidney and brain cortex of male mini pigs (4000-5000 g) after seven days of total parenteral nutrition (TPN) with amino acids 5% (3.0g/kg/d), glucose (25g/kg/d) and lipids 20% (4g/kg/d). This regime was administered with L-carnitine supplementation (1.

[Animal experiment studies on the changes in lipid and protein metabolism in L-carnitine-supplemented total parenteral nutrition].

The influence of i.v. L-carnitine on parameters of lipid- and nitrogen metabolism was studied during total parenteral nutrition of mini pigs (x: 4077; n = 9).

[Indication and practical aspects of perioperative parenteral nutrition].

By means of the present clinical findings it is demonstrated that an improvement of the preoperative nutritional status goes along with a reduction of the postoperative rates of mortality and complications. The effects of postoperative catabolism compared with chronic protein losses are shown. It is demonstrated that acute catabolism is essentially at the cost of viscerally synthesized and functionally important protein systems whereas chronic states of catabolism mainly affect the structural protein of the overall organism.

[Effect of human growth hormone on nitrogen retention].

A 13-year-old female, suffering from chronic juvenile arthritis, whose disease and medication had caused a severe catabolic state, was alimented orally and parenterally for a 32-day period. The influence of an intravenous supplement of arginine to stimulate endogenous human growth hormone (HGH) secretion, e.g.

Deficiencies of essential fatty acids and vitamin E in cystic fibrosis.

In 25 children (13 male; 12 female) with cystic fibrosis aged 6 months to 16 years and 24 matched controls total serum vitamin E levels and fatty acid patterns of serum cholesterol esters, phospholipids and triglycerides are demonstrated. Compared to controls (1.02 +/- 0.

Effects of essential fatty acid deficiency on various functions of the rat erythrocyte membrane.

Various membrane transport functions have been studied in erythrocytes from essential fatty acid (EFA) deficient rats in order to determine whether or not functional abnormalities induced by documented EFA-deficiency of the membrane could be demonstrated. No differences were found between EFA deficient and control cells with respect to mean values for osmotic resistance or intracellular sodium and potassium concentrations. However, uptake of leucine by EFA deficient erythrocytes was significantly greater than that of control erythrocytes.

[Diagnosis of malnutrition].

A diagnostic program for routine determination of the nutritional status during initial examination is presented. This program includes anthropometric methods (body weight, height, triceps skin fold, circumference of mid-arm muscle) and chemical parameters (creatinine index, albumin, prealbumin, cholesterinase). In addition, determination of the immune status through the absolute lymphocyte count in peripheral blood and intracutaneous testing with streptokinase-dornase, mumps skin test antigen and candida vaccine is recommended.

[Nutritional states in a medical clinic].

The nutritional state of 168 patients in a medical clinic was determined with the following parameters: Weight/height index, triceps skin fold, arm muscle circumference, creatinine/height index, albumin, prealbumin, transferrin and cholinesterase. Using these parameters we found that 51.2% of these patients were suffering from malnutrition (26.

Argininosuccinic aciduria: metabolic studies and effects of treatment with keto-analogues of essential amino acids.

A 22 years old female with the late-onset of argininosuccinic aciduria was successfully treated for 5 months with a mixture of essential amino acids and their keto-analogues. There was a marked change in plasma ammonia, plasma amino acids and argininosuccinic acid excretion. A long term anabolic response was reflected by an increase of total serum proteins and serum albumin by about 1 g/dl during the first 5 months of treatment.

Protein load in argininosuccinic aciduria: thoughts on its biochemical implications.

A patient with argininosuccinc aciduria was charged with 50 grams of protein, which was followed by considerable hyperammonemia. There was no response in further urea formation; but there was a considerable production of orotic acid, a precursor of pyrimidines. This makes orotic acid to an important diagnostic tool for the diagnosis of impaired urea formation.

[Dosage of calcium and phosphate in parenteral feeding].

In a carbohydrate combination solution containing 12.5 mEq/1 calcium and 12 mmol/1 phosphate the concentrations of calcium and phosphate were kept constant during parenteral infusion therapy with carbohydrate, at a rate of 0.5 g/kg/h and amino acids at a rate of 0.