Search PubMed⌕ Search

Biomedical subjects

L Gibson

Publications and source records attributed to L Gibson.

At least 55 records · Page 3Linked to original sources

Erythropoietin bioassays using fetal mouse liver cells: validations and technical improvements.

Studies are described which were designed to compare an erythropoietin (Ep) bioassay using the uptake of 125I-deoxyuridine (125-I-UdR) into whole cells cultured in micro-titer plates with an established method where the cells were cultured in 1 ml volumes using the incorporation of 59Fe into heme as the endpoint. The results demonstrate the validity of the substitution of 125I-UdR uptake into whole cells as a replacement for 59Fe incorporation into heme as an assay endpoint and the adaptation of the method to a semi-micro scale with automated cell harvesting. A culture time significantly shorter than 24 h is demonstrated not to be of practical benefit. Two methods are proposed to saturate the growth promoting effects of iron-containing transferrin. The performance of semi-micro, serum-containing bioassay employing untreated serum as the test material is shown to be superior to previous systems for the biological measurement of Ep.

Animals↗

The assessment of health in casualty birds of prey intended for release.

There are legal implications in deciding when a sick or injured bird or prey is able to be released. Important considerations are the health of the bird, its relationship with man and the locality in which it is to be released. Recommendations are made in order to help veterinary surgeons tackle this problem. Criteria for assessing health are outlined and discussed.

Animals↗

Cytoskeleton-disrupting drugs enhance effect of growth factors and hormones on initiation of DNA synthesis.

Addition of growth factors, such as prostaglandin F2 alpha or fibroblastic growth factor, to quiescent Swiss mouse 3T3 cells resulted in an abrupt increase in the rate of initiation of DNA synthesis after a lag phase of 13-15 hr. This increase could be quantified by a rate constant k. Addition of colchicine, Colcemid, or vinblastine had a synergistic effect on the initiation of DNA synthesis triggered by PGF2 alpha or FGF by increasing the value of k. These drugs alone had no effect. Colchicine had a synergistic effect only if added within 8 hr of the PGF2 alpha or FGF addition. Also, colchicine exerted its full effect when it was present only for the first 5 hr with either growth factor. These results suggest that an intact cytoskeleton is not required for the initiation of DNA synthesis. Furthermore, cytoskeleton-disrupting drugs enhance the stimulatory effect of the growth factors.

Animals↗

Alcohol and rape in Winnipeg, 1966-1975.

Either victim or rapist or both were drinking prior to 72% of the rapes occurring in Winnipeg from 1966 through 1975, and the presence of alcohol increased the likelihood that the victim would be injured prior to sexual intercourse.

Adult↗

Recurrent venous thrombosis with a "lupus" coagulation inhibitor in the absence of systemic lupus.

A young man presenting with recurrent deep venous thrombosis was found to have a lupus type coagulation inhibitor. He showed neither clinical nor serological evidence of systemic lupus. The value of the Russell viper venom coagulation time in the detection of the inhibitor is demonstrated. Anticoagulant therapy has not caused any bleeding complication despite the presence of the inhibitor.

Adult↗

Judging the effectiveness of clinical pathways for pneumonia: the role of risk adjustment.

CONTEXT: Although observational studies suggest that clinical pathways may decrease costs and improve quality in hospitalized patients with community-acquired pneumonia, inferences from these studies are limited by potential selection bias and inadequate case-mix adjustment. OBJECTIVE: To compare the assessment of a clinical pathway for community-acquired pneumonia with and without adjusting for patient characteristics and disease severity. DESIGN: Retrospective cohort study. PATIENTS AND SETTING: Consecutive series of adult patients admitted with clinical diagnosis of community-acquired pneumonia, treated with either a clinical pathway (which included guidelines for antibiotics, tests, and ancillary care) or usual care. MAIN OUTCOME MEASURES: Total hospital charges, length of stay, clinical deterioration (requiring mechanical ventilation or intensive care unit transfer), and in-hospital mortality. We used multiple linear and logistic regression to adjust for patient case mix. RESULTS: Compared with patients receiving usual care (n = 275), patients in the pathway group (n = 97) were more likely to be treated by family physicians than specialists and had lower pneumonia severity scores. In the unadjusted analysis, total hospital charges were lower among pathway patients ($2456; 95% CI, $175 to $4737; P = 0.04); in the adjusted analysis, the difference in total charges was smaller (average reduction $1807; CI, $4164 lower to $549 higher; P = 0.13). In the unadjusted analysis, length of stay was lower among pathway patients (1.8 days lower; CI, 3.9 lower to 0.4 higher; P = 0.12); in the adjusted analysis, the difference in length of stay was smaller (0.9 days lower; CI, 3.2 lower to 1.3 higher; P = 0.4). Although unadjusted analysis showed significantly lower in-hospital mortality in pathway patients, this difference was not confirmed in the adjusted analysis. CONCLUSIONS: Clinical pathways may reduce costs and improve quality of care in community-acquired pneumonia. In nonrandomized studies, however, selection bias and case-mix differences may explain some of the apparent effectiveness.

Adult↗

Patient education: effects of two teaching methods upon parental retention of infant feeding practices.

PURPOSE: The purpose of this study was to test a strategy for improving patient's retention of discharge teaching. METHODOLOGY: A pretest-posttest experimental design was used. Forty postpartum women were randomly assigned to a group. All subjects received infant feeding instruction until they reached criterion on the Infant Feeding Questionnaire. The experimental group received additional instruction on the same material (overlearning). The two groups were compared 2 weeks later on the same questionnaire. Mean scores were compared by a t-test, demographic variables were correlated to outcomes, and effect of race or culture was analyzed by ANOVA. FINDINGS: The pretest showed no significant difference between the groups. Posttest scores were significantly higher for the experimental group. The mother's education was the only demographic variable that was correlated to the results. CONCLUSION: Mothers who receive overlearning beyond the mastery level retain significantly more of the material.

Adolescent↗