PubMed Health⌕ Search

Biomedical subjects

B Lyman

Publications and source records attributed to B Lyman.

10 recordsLinked to original sources
PubMed1992

Insulin-like growth factor-binding protein-3 proteolysis is induced after elective surgery.

The insulin-like growth factors (IGFs) are bound to several binding proteins (IGFBPs) that appear to regulate IGF transport, receptor binding, and action. The concentrations of these peptides are altered by catabolic conditions. To determine if IGF-I and IGFBP levels change after surgery, sera were obtained from 16 patients before and after cholecystectomy. Immunoreactive IGF-I measured in plasma samples from which IGFBPs had been extracted did not change postoperatively. In contrast, IGF-I determined in unextracted samples increased roughly 3-fold postoperatively, presumably due to changes in IGFBPs. Two days postoperatively, IGFBP-3 levels, determined by ligand blot, averaged 36% of preoperative values, whereas levels of IGFBP-2 and a 24,000 mol wt IGFBP did not change significantly. Similarly, by immunoblot, intact IGFBP-3 was decreased 84.2 +/- 20.2%, and a 31,000 mol wt IGFBP-3 fragment increased 57.5 +/- 47.4% postoperatively. Coincubation of postoperative, but not preoperative, sera with control sera resulted in a significant decrease in IGFBP-3 and production of proteolytic fragments. IGFBP-3 proteolytic activity in postoperative sera was markedly inhibited by antipain, Na-p-tosyl-L-lysine chloromethyl ketone, phenylmethylsulfonylfluoride, aprotinin, o-phenanthroline, and EDTA, but not by leupeptin or N-tosyl-L-phenylalanine chloromethyl ketone. This pattern of inhibition is consistent with a metal-dependent trypsin-like serine protease. We speculate that proteolysis of IGFBP-3 may alter tissue uptake of IGF-I and thereby help to counteract the catabolic state caused by surgery.

Blood Physiological Phenomena↗
PubMed1987

The role of the nutritional support team in preventing and identifying complications of parenteral and enteral nutrition.

As the technology of parenteral and enteral nutrition advances, a multidisciplinary nutritional support team (NST) can be used to assure quality care. NST functions include developing and using standard protocols and solutions, monitoring patients, and preventing complications. Interventions by NSTs can save money for the hospital as well. Examples from Truman Medical Center (Kansas City, Missouri) illustrate how the NST can perform these functions.

Enteral Nutrition↗
PubMed1986

Sepsis from triple- vs single-lumen catheters during total parenteral nutrition in surgical or critically ill patients.

We prospectively studied the infection rates for 59 triple-lumen (TLC) and 68 single-lumen (SLC) subclavian catheters during the administration of total parenteral nutrition (TPN) to surgical or critically ill patients. A standard protocol was used for catheter insertion and maintenance. The infection control committee determined independently whether patients had catheter-related sepsis, an infected insertion site only, or no catheter infection. The TLCs had an increased incidence of catheter sepsis (19%) compared with the SLCs (3%). Low rates (5% for TLCs and 3% for SLCs) of infected catheter sites only indicated that the catheter care was comparable for both groups. The patients in the two groups were similar but not identical; those with TLCs appeared to be sicker and, therefore, at greater risk to develop catheter sepsis than patients with SLC. However, since TLCs were involved in six times more catheter sepsis than were SLCs, limiting the use of a subclavian catheter to giving TPN only and strict adherence to a TPN protocol are necessary to minimize the risk of catheter sepsis.

Candidiasis↗
PubMed1982

The nutritional values and food group characteristics of foods preferred during various emotions.

One hundred university students were asked to indicate the foods they would prefer when experiencing 22 common emotions. The preferences were categorized in terms of nutritional values and were also tallied in terms of the four basic food groups. Application of Cochran's Q Test showed that there were highly significant differences among emotions in the frequencies of preferences for foods of different nutritional values and the frequencies of preferences among the food groups. The chi square test showed that for all but eight emotions, the frequencies were significantly larger for healthy than for junk foods. The results are discussed with reference to emotional needs and diet selection.

Adolescent↗
PubMed1979

Representation of complex emotional and abstract meanings by simple forms.

Using curved and angular line drawings, several investigators found a relation between form and meaning in individuals reared before the age of television. In the present study 60 university students who had been exposed to television from earliest childhood were asked to indicate whether a curved or angular figure best represented each of 40 emotion or abstract concepts. For 36 of the concepts the frequencies were significantly different from a chance level, and it was concluded that television viewing had no adverse effect on the fittingness of form and meaning. Several possible explanations for the phenomenon are discussed.

Adolescent↗
PubMed1971

Biochemical and biophysical aspects of human platelet adhesion to collagen fibers.

A method has been developed for measuring the adhesion of platelets to purified collagen fibers obtained from bovine tendon. This method differs from others in that: (a) platelet adhesion is measured in the absence of platelet aggregation; (b) platelet-rich plasma collected in ACD (acid citrate dextrose) or EDTA, or washed platelets can be employed; (c) adherent platelets are enumerated directly; (d) erythrocytes and leukocytes do not adhere. Washed platelets suspended in human Ringer solution exhibit negligible adhesion (at the platelet concentrations employed) in contrast to washed platelets suspended in plasma. Addition of purified human fibrinogen (95% clottable, 2-4 mg/ml) to human Ringer solution completely restores the ability of washed platelets to adhere to collagen fibers. Albumin (fatty acid free, 50 mg/ml) is also capable of restoring adhesion. Albumin and seven other proteins at concentrations of 5-10 mg/ml, with varying molecular weights, isoelectric points, and frictional coefficients are incapable of supporting the adhesion of washed platelets. The proteins tested were human globulin, hexokinase, hemoglobin, cytochrome-C, insulin, thyroglobulin, and muramidase. Platelet adhesion is proportional to both platelet concentration and fibrinogen concentration, but is independent of temperature or glycogen stores. Modification of fibrinogen by acylation of amino groups or removal of sialic acid has no effect on its ability to support platelet adhesion. Degradation of fibrinogen with purified plasmin results in decreased support of platelet adhesion. This accompanied formation of early breakdown products with clottability ranging from 84-0%. Formation of fibrinogen degradation products was monitored by SDS-polyacrylamide gel electrophoresis of the corresponding fibrins after reduction of disulfide bonds (a method capable of distinguishing alpha-, beta- and gamma-chains). Decreased support of platelet adhesion is associated with the disappearance of intact alpha- chains and early modification of the beta-chains. Purified proteinpolysaccharide macromolecules obtained from bovine nasal and humeral cartilage, and from nucleosus pulposus are as effective as fibrinogen on a weight basis and ten to thirty times more effective on a molar basis in supporting platelet adhesion. The purified mucopolysaccharide side chains: chondroitin-4-sulfate, chondroitin-6-sulfate, and keratan-sulfate are incapable of supporting platelet adhesion.

Adsorption↗
PubMedDate not supplied

Enteral feeding in the hypoalbuminemic patient.

Previous studies have correlated intolerance of isotonic, intact protein enteral solutions with hypoalbuminemia. The purpose of this retrospective study was to determine whether the level of serum albumin (SA) influenced tolerance of such an enteral nutrient solution (ENS). All patients who received Entrition during 1987 for a minimum of 48 hr were studied for the first 10 days of enteral feeding. Documentation included SA, medications, stool frequency, gastric residuals (GR), and daily caloric intake. ENS intolerance was defined as greater than 3 stools/day for greater than 48 hr or GR greater than twice the hourly infusion rate for greater than 48 hr. Patients were categorized into two groups: those with SA greater than or equal to 2.5 g/dl (group I) and those with SA less than 2.5 g/dl (group II). Of 88 patients studied, 48 (86%) in group I and 28 (88%) in group II tolerated the ENS. Eight (14%) in group I and 4 (12%) in group II experienced ENS intolerance. There was no statistically significant difference in the frequency of ENS intolerance between these two groups (p less than 0.05). Also, 97% of all those with a SA less than 2.5 g/dl were fed 80% or more of their estimated caloric requirements. We concluded that ENS tolerance was not affected by the SA level and patients with hypoalbuminemia (SA less than 2.5 g/dl) could be fed enterally.

Adult↗