Search PubMed⌕ Search

Biomedical subjects

G L Jensen

Publications and source records attributed to G L Jensen.

At least 37 records · Page 2Linked to original sources
PubMed1996

A double-blind, prospective, randomized study of glutamine-enriched compared with standard peptide-based feeding in critically ill patients.

Arterial and venous plasma amino acids were determined in 28 intensive care patients randomly assigned to receive 10 d of isoenergetic, isonitrogenous feedings that differed sixfold in glutamine content. Subjects were generally well-matched for age, injury severity, and disease diagnoses. Nasojejunal feedings were started within 48 h of admission. Data were analyzed from those 19 subjects still receiving > or = 50 mL feeding/h on day 5. Both groups had comparable gastric residuals, stool frequency, and delivered nitrogen and energy. At study initiation, all subjects had relative hypoaminoacidemia, with day 1 venous glutamine concentrations down 26% compared with reference values. Plasma glutamine rose to comparable concentrations with feeding of either diet. There were, however, significant (P < 0.05) increases in arterial or venous plasma total, indispensable, and branched-chain amino acids of 125-144% by day 5 only in patients fed the standard control diet. The phenylalanine-tyrosine ratio was elevated on day 1 in both groups (1.3-1.4) but decreased significantly only in the glutamine-supplemented group (1.1 compared with 1.4) by day 5. Glutamine supplementation blunted the hyperaminoacidemia and elevated aromatic amino acid response to injury.

APACHE↗
PubMed1995

Early enteral administration of a formula (Impact) supplemented with arginine, nucleotides, and fish oil in intensive care unit patients: results of a multicenter, prospective, randomized, clinical trial.

OBJECTIVE: To determine if early enteral feeding, in an intensive care unit (ICU) patient population, using a formula supplemented with arginine, dietary nucleotides, and fish oil (Impact), results in a shorter hospital stay and a reduced frequency of infectious complications, when compared with feeding a common use enteral formula (Osmolite.HN). DESIGN: A prospective, randomized, double-blind, multicenter trial. SETTING: ICUs in eight different hospitals. PATIENTS: Of 326 patients enrolled in the study, 296 patients were eligible for analysis. They were admitted to the ICU after an event such as trauma, surgery, or sepsis, and met a risk assessment screen (Acute Physiology and Chronic Health Evaluation II [APACHE II] score of > or = 10, or a Therapeutic Intervention Scoring System score of > or = 20) and study eligibility requirements. Patients were stratified by age (< 60 or > or = 60 yrs of age) and disease (septic or systemic inflammatory response syndrome). INTERVENTIONS: Patients were enrolled and full-strength tube feedings were initiated within 48 hrs of the study entry event. Enteral feedings were advanced to a target volume of 60 mL/hr by 96 hrs of the event. One hundred sixty-eight patients were randomized to receive the experimental formula, and 158 patients were randomized to receive the common use control formula. MEASUREMENTS AND MAIN RESULTS: Both groups tolerated early enteral feeding well, and the frequency of tube feeding-related complications was low. There were no significant differences in nitrogen balance between groups on study days 4 and 7. Patients receiving the experimental formula had a significant (p = .0001) increase in plasma arginine and ornithine concentrations by study day 7. Plasma fatty acid profiles demonstrated higher concentrations of linoleic acid (p < .01) in the patients receiving the common use formula and higher concentrations of eicosapentaenoic and docosahexaenoic acid (p < .01) in the patients receiving the experimental formula. The mortality rate was not different between the groups and was significantly (p < .001) lower than predicted by the admission severity scores in both feeding groups. In patients who received at least 821 mL/day of the experimental formula, the hospital median length of stay was reduced by 8 days (p < .05). In patients stratified as septic, the median length of hospital stay was reduced by 10 days (p < .05), along with a major reduction in the frequency of acquired infections (p < .01) in the patients who received the experimental formula. In the septic subgroup fed at least 821 mL/day, the median length of stay was reduced by 11.5 days, along with a major reduction in acquired infections (both p < .05) in the patients who received the experimental formula. CONCLUSIONS: Early enteral feeding of the experimental formula was safe and well tolerated in ICU patients. In patients who received the experimental formula, particularly if they were septic on admission to the study, a substantial reduction in hospital length of stay was observed, along with a significant reduction in the frequency of acquired infections.

APACHE↗
PubMed1994

Lymphatic absorption of enterally fed structured triacylglycerol vs physical mix in a canine model.

The lymphatic absorption of a structured triacylglycerol vs an equivalent physical mixture of the constituent medium-chain triacylglycerol and fish oils was studied. Each of four canines served as its own control in a crossover feeding design with the investigators unaware of diet contents. Lymphatic absorption of n-3 and medium-chain fatty acids peaked within 4-8 h of feeding either diet. The lymph contained more 10:0 fatty acids than 8:0 despite an overall ratio of 10:0 to 8:0 of 0.3 for the diets. The mass of medium-chain fatty acids absorbed in the lymph at measured time points was 2.6 +/- 0.5-fold higher (mean +/- SE of 12 determinations) for the structured triacylglycerol compared with the physical mix. Molecular species analyses revealed that the medium-chain fatty acids in lymph were present as mixed triacylglycerols. The unique molecular structure of these mixed triacylglycerols and the fatty acids at the 2-position may account for the improved absorption.

Absorption↗
PubMed1994

Risk factors for Clostridium difficile stool cytotoxin b among critically ill patients: role of sucralfate.

To identify risk factors other than antimicrobial exposure for Clostridium difficile stool cytotoxin b, subjects admitted to critical care units over 18 months and who had stool cytotoxin assays were evaluated. Twenty-two cases (cytotoxin b-positive) were compared with 125 controls (cytotoxin b-negative). Cases and controls were similar with respect to age, sex, therapeutic index severity score, duration of hospitalization before cytotoxin b testing, and antimicrobial exposure. Adjusted odds ratios (OR) revealed white blood cell count of > 12,000 on the day of stool sampling (OR, 4.0; 95% confidence interval [CI], 1.3-12.4) and sucralfate exposure (OR, 0.15; 95% CI, 0.05-0.42) as significant independent positive and negative risk factors, respectively. Sucralfate exposure may decrease risk for C. difficile stool cytotoxin b by interfering with its detection, altering toxin production, or inhibiting colonization by the organism. Additional evaluation is needed to elucidate the mechanisms involved.

Aged↗
PubMed1990

Overzealous resuscitation of an extremely malnourished patient with nutritional cardiomyopathy.

Overzealous resuscitation of the severely malnourished patient may be associated with life-threatening complications. A variety of electrolyte, hemodynamic, septic, and nutritional derangements may result in sudden decompensation and even death. We present a case that dramatically illustrates these complications and focuses on the key role of underlying nutritional cardiomyopathy.

Adult↗
PubMed1989

Dietary modification of chyle composition in chylothorax.

Nutrition support has played a major role in the treatment of chylothorax, both to prevent malnutrition and to minimize chyle production and flow. This report evaluates chyle composition in a patient with chylothorax who was placed on a low-fat diet, medium-chain triglyceride diet, and total parenteral nutrition in sequence. Both triglyceride content and volume of chyle declined, but drainage persisted, ultimately requiring thoracic duct ligation. The chyle triglyceride while on total parenteral nutrition, which presumably originates from both the intestine and plasma, contained more long-chain unsaturated fatty acids than the circulating serum triglyceride. Of particular interest was the detection of an appreciable amount of medium-chain fatty acids in the chyle triglyceride, constituting 20% of the triglyceride fatty acids when an enteral formulation with medium-chain triglyceride as a sole fat source was administered. The finding of almost threefold more decanoic acid (C10:0) than octanoic acid (C8:0), despite the presence of considerably more octanoic acid in the original diet, suggests that trioctanoin may be a preferable medium-chain triglyceride substrate for the nonsurgical treatment of chylothorax.

Adult↗
PubMed1984

Radioprotection by glutathione ester: transport of glutathione ester into human lymphoid cells and fibroblasts.

Glutathione is not effectively transported into human lymphoid cells, normal human skin fibroblasts, and fibroblasts from patients with genetic deficiencies of gamma-glutamylcysteine synthetase or glutathione synthetase. On the other hand, the monoethyl ester of glutathione, in which the carboxyl group of the glycine residue is esterified, is readily transported into these cells and is hydrolyzed intracellularly. This leads to greatly increased cellular levels of glutathione, which often exceed those found normally. Glutathione ester was found to protect human lymphoid cells of the CEM line against the lethal effects of irradiation. Under the conditions employed, complete protection was found when the ester was added prior to irradiation. Addition of the ester after irradiation was partially effective, suggesting that GSH may also function in repair processes.

Biological Transport↗
PubMed1983

Radioprotection of human lymphoid cells by exogenously supplied glutathione is mediated by gamma-glutamyl transpeptidase.

Human lymphoid cells depleted of glutathione by treatment with buthionine sulfoximine, a specific inhibitor of gamma-glutamylcysteine synthetase, may be partially repleted by adding glutathione in the medium. The mechanism of repletion involves the action of gamma-glutamyl transpeptidase on exogenous glutathione, transport of products of glutathione metabolism, and intracellular synthesis of glutathione. Lymphoid cells, previously shown to export glutathione at rates proportional to intracellular glutathione levels, do not take up intact glutathione to an appreciable extent, even under conditions of marked glutathione deficiency. The role of glutathione in radioprotection was examined by subjecting cells to gamma-radiation after modification of cellular glutathione levels. Glutathione-depleted cells exhibited increased radiosensitivity under aerobic conditions, as compared to the nondepleted controls. Partial repletion of cellular glutathione prior to irradiation led to radiosensitivity comparable to nondepleted controls. Cells were not protected by suspension in media containing glutathione just prior to irradiation; thus, protection appears to require intracellular glutathione.

Acyltransferases↗
PubMed1982

Triacylglycerol lipase, monoacylglycerol lipase and phospholipase activities of highly purified rat hepatic lipase.

Highly purified rat hepatic lipase (NaCl-resistant, alkaline pH optimum) was studied to evaluate whether the enzyme has triacylglycerol lipase, monoacylglycerol lipase and phospholipase activities. Enzyme exhibiting a single band by SDS-polyacrylamide gel electrophoresis and having a specific activity eight times greater than that in any previous report was utilized. The ratios of the different lipolytic activities to each other remained constant throughout a multistep hepatic lipase purification. The lipolytic activities coeluted by gel filtration on Ultrogel AcA 34. Column isoelectric focusing of the highly purified enzyme revealed comigration of the lipolytic activities. Thermal inactivation produced similar decay curves for the different activities. Immune titration curves for the different activities with specific antibody against hepatic lipase were essentially identical. These findings indicate that hepatic lipase is a single enzyme molecule which has triacyglycerol lipase, monoacylglycerol lipase and phospholipase activities with artificial substrates. To study these lipolytic activities further, purified hepatic lipase was subjected to limited digestion by specific proteases. The triacylglycerol lipase activity was more sensitive to proteolytic destruction than either of the other two activities.

Animals↗