PubMed Health⌕ Search

Biomedical subjects

B Webster

Publications and source records attributed to B Webster.

15 recordsLinked to original sources
PubMed1986

Beta-adrenergic modulation of insulin binding in skeletal muscle.

Both a high physiological concentration (13.1 nM) of epinephrine (E) and acute exercise (AEx) have previously been shown to increase 125I-insulin binding in skeletal muscle. To investigate the site and mechanism of the effect of epinephrine on binding and the possible link between epinephrine- and AEx-enhanced insulin binding, we measured insulin binding in three different preparations: 1) crude membranes derived from whole soleus muscle incubated in vitro with 13.1 nM E, 2) crude membranes with E present in the binding assay, and 3) purified plasma membranes with E present. Epinephrine enhanced binding in all three preparations by 169, 144, and 164%, respectively, at low concentrations of insulin but had little effect at high concentrations. Epinephrine, therefore appears to have its effect at the plasma membrane. Propranolol (10 microM), a beta-adrenergic antagonist, blocked E-enhanced insulin binding and when added to crude membranes made from soleus and extensor digitorum longus muscle of AEx rats reversed the increase in binding seen with exercise. This indicates that E-enhanced insulin binding is mediated by beta-adrenergic receptors and that AEx enhances insulin binding via beta-adrenergic receptors. Sodium orthovanadate (3 mM), a phosphotyrosyl-protein phosphatase inhibitor, also inhibited the increase in insulin binding due to E, implying that E may increase insulin binding by activating a phosphotyrosyl-protein phosphatase which decreases the phosphorylation of a plasma membrane protein, presumably the insulin receptor.

Animals↗
PubMed1975

The assessment and progress of long-stay and elderly psychiatric patients: the predictive validity of a ward behaviour questionnaire.

This paper describes an attempt to validate a behaviour rating scale used to predict the likelihood of discharge among elderly and long-stay patients in a psychiatric hospital. The scale measured behaviour on the ward as rated by nursing staff. The scale was a sensitive predictor of discharge among those with a low score (indicating least disability), except for patients with organic psychoses. However, many patients with low scores were not discharged. In order to improve the scale's use as a screening technique additional information was considered. The significance of the findings is discussed.

Activities of Daily Living↗
PubMedDate not supplied

Clinical indicators of dehydration severity in elderly patients.

STUDY OBJECTIVE: To determine which of the signs and symptoms of dehydration obtainable from patient history and physical examination in the emergency department are most useful in assessing the severity of dehydration in elderly patients. DESIGN: Prospective, correlational study. SETTING: Two university teaching hospitals. PATIENTS: Fifty-five patients aged 60 or older presenting to the emergency department with suspected dehydration were studied. MEASUREMENTS AND MAIN RESULTS: In the emergency department, patients were evaluated by a standardized history and physical examination that included assessment of 38 signs and symptoms commonly attributed to dehydration. The relationships between the presence and intensity of these putative dehydration indicators and an independent rating of dehydration severity based on a comprehensive review of the medical record were evaluated. Also evaluated were the relationships between these dehydration indicators and patient age. Indicators that correlated best with dehydration severity but were unrelated to patient age included: tongue dryness (P less than 0.001), longitudinal tongue furrows (P less than 0.001), dryness of the mucous membranes of the mouth (P less than 0.001), upper body muscle weakness (P less than 0.001), confusion (P less than 0.001), speech difficulty (P less than 0.01), and sunkenness of eyes (P less than 0.01). Other indicators had only weak associations with dehydration severity or were also related to age. Patient thirst was unrelated to dehydration severity. CONCLUSIONS: A set of signs and symptoms related to dehydration severity in elderly patients has been identified. These indicators may be more useful for evaluation of dehydration severity in the emergency department than other commonly used indicators.

Aged↗
PubMedDate not supplied

Effect of body positions and splints in bioelectrical impedance analysis.

The objective of this study was to evaluate body composition as measured by bioelectric impedance analysis using splints and body positions differing from the standard supine position. Forty-three patients, randomized into two groups of different body positions, and 101 healthy volunteers were prospectively studied. Resistance and reactance of body tissues were measured by bioelectric impedance analysis. Body composition is described by a three-compartment model composed of body fat, body cell mass, and extra cellular mass. The patients were measured in the standard supine position and then randomized into two groups. They were then remeasured with the appropriate splinting device or position change. Volunteers were measured in the standard supine position and all four alternative positions. There was a statistically significant difference demonstrated in whole body resistance, whole body reactance, body cell mass, and the ratio of extracellular mass to body cell mass in some body positions. The percentage of change with different body positions and splints, when compared with the standard supine position, was generally below 2%, a clinically insignificant difference. We conclude that the reliability of resistance and reactance as measured by bioelectric impedance analysis is clinically valid using any of the tested body positions and/or splints. The three-compartment model may be a useful concept to measure body composition changes in both healthy and sick persons.

Body Composition↗
PubMedDate not supplied

Detecting leprosy.

Explore the source record for details and available documents.

Adult↗