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S Watt

Publications and source records attributed to S Watt.

53 records · Page 3Linked to original sources
PubMed1983

Separation of hemopoietic cells from adult mouse marrow by use of monoclonal antibodies.

Primitive hemopoietic progenitor cells from adult mouse marrow have been substantially enriched by virtue of a negative selection procedure with monoclonal antibodies. It has been possible to segregate erythroid progenitor cells at distinct stages of differentiation on the basis of their cell surface antigens. This has been achieved with two monoclonal antibodies reactive with the mature elements of bone marrow. YBM 34.3 binds to a heat-stable antigen expressed on B lymphocytes, neutrophils, and cells of the erythroid lineage. YBM 6.1 reacts with cells of the neutrophil, eosinophil, and monocyte series but does not bind to colony-forming cells. Separation is achieved by indirect immunoadsorption (panning) with YBM 34.3 on Protein-A-coated plastic plates followed by FACS II cell sorting with YBM 6.1. The combined procedures yield a marrow population containing 58% immature cells (blasts, promyelocytes, and myelocytes) and 9.5% clonogenic cells. In addition, differential binding of YBM 34.3 can be used to segregate erythroid progenitor cells at distinct stages of differentiation (day 7 BFU-E, day 5 BFU-E and CFU-E) either by cell sorting or panning. It is shown that both techniques give a comparable degree of resolution of the different cell types with, however, an appreciable advantage of panning over cell sorting in allowing the rapid handling of large numbers of cells.

Animals↗
PubMed1981

Tumor angiogenic factor. Purification from the Walker 256 rat tumor.

We report here the purification of an angiogenic substance from the Walker 256 rat ascites tumor which is mitogenic for fetal bovine aortic endothelial cells in culture and which also stimulates new blood vessel growth in vivo. Purification was monitored in endothelial cell cultures by cell counting or by [3H]thymidine incorporation into DNA. Lyophilized crude tumor cell homogenate was extracted with absolute ethanol, and the extract was further purified by silica gel column chromatography. The most purified material eluted with ethyl acetate:methanol (25:1) and behaved as a single component when analyzed either by thin layer chromatography with both silica gel and polyethylene-imine-cellulose systems or by reversed phase (C18) high pressure liquid chromatography. Bio-Gel P-30 chromatography indicates a Mr 400-800 for the active material. The mitogenic activity of the purified material was observed with the vascular endothelial cells cultured in serum-less as well as serum-containing media. The angiogenic activity of this material was revealed in both the chicken chorioallantoic membrane and rat corneal micropocket bioassays. Our results demonstrate that a factor with mitogenic and angiogenic activities can be purified from the Walker rat tumor by a novel, facile, and high yield process.

Angiogenesis Inducing Agents↗
PubMed1981

A corneal micropocket assay for angiogenesis in the rat eye.

A corneal micropocket assay for angiogenesis in the rat eye is described in detail. With our test system, a partially purified, low molecular-weight endothelial cell growth stimulatory factor isolated from the Walker 256 rat carcinosarcoma is demonstrated to have potent angiogenic activity in vivo. The advantages and applications of our rat corneal assay are discussed.

Animals↗
PubMedDate not supplied

Problem-solving counseling for caregivers of the cognitively impaired: effective for whom?

BACKGROUND: Individualized problem-solving counseling for caregivers of cognitively impaired relatives is thought to help caregivers cope with the stress and burden of caregiving. Few studies have shown the effectiveness of counseling for these caregivers. OBJECTIVES: To determine the effectiveness of individualized problem-solving counseling by nurses for caregivers and the expenditures of health care utilization. METHOD: Caregivers (n = 77) of the cognitively impaired living at home were randomized to receive nurse counseling or not. Psychosocial adjustment to their relative's illness, psychological distress, burden, coping skills, and expenditures were measured after 6 months and 1 year. RESULTS: Although on average, all caregivers receiving nurse counseling indicated no improvement in psychosocial adjustment to their relative's illness, psychological distress, or caregiver burden, they found counseling very helpful and it was effective for a subgroup of caregivers. Those with poor logical analysis coping skills at baseline had decreased psychological distress (F(1,53) = 9.7, p = .003) and improved psychosocial adjustment (F(1,53) = 4.7, p = .035) after 1 year. Caregivers in control and counseling groups whose relatives entered a nursing home improved their psychosocial adjustment 23% on average whereas those continuing to live in the community decreased by 8%. Almost half as many relatives entered nursing homes in the counseling group (n = 9 vs. n = 5) but these compared to control group relatives had greater annualized per person expenditures for health and social services (Cdn$23,437 vs. Cdn$15,151). CONCLUSIONS: Caregivers found nurse counseling most helpful. Those indicating infrequent use of logical analysis coping skills showed benefits.

Adaptation, Psychological↗
PubMedDate not supplied

Electives in Europe.

Student nurses at Napier University in Edinburgh have the opportunity to study extracurricular French or German and to gain experience of working in Europe. The authors of this article suggest that this gives students the skill and confidence to practise abroad, and to influence nursing policy and development in the European Union.

Curriculum↗
PubMedDate not supplied

Understanding newborn infant readmission: findings of the Ontario Mother and Infant Survey.

The Ontario Mother and Infant Survey examined health and social service utilization of postpartum women and newborn infants from five hospital sites. A cross-sectional multilanguage survey design with longitudinal follow-up was used: 1,250 eligible, consenting women completed a self-report questionnaire in hospital and 875 women participated in a structured telephone interview at four weeks post-discharge. Rates of newborn infant readmission ranged from 2.4% to 6.7%. The best predictors of readmission were: main source of household income was other than employment; maternal self-rating of health was poor; mother anticipated inadequate help and support at home following discharge; mother received help from friends/neighbours following discharge; and mother had concern about infant care and behaviour. Readmission was not associated with length of postpartum hospital stay. The study findings suggest that there is a complex relationship between infant health care needs, family resources and provider practices that produces clinically important, site-specific readmission patterns.

Female↗
PubMedDate not supplied

Public health nursing clientele shared with social assistance: proportions, characteristics and policy implications.

This study was designed to determine (1) the extent to which public health nursing visits and social services income programs serve the same population (shared clientele), (2) whether shared and unshared clientele differ in their characteristics, and (3) whether those who use both these services are high users of other health and social services. A computerized record linkage showed that 17% of individual public health nursing clients were shared with social services. Shared clientele had more social, perinatal, emotional and mental health problems. It is these characteristics, rather than the simultaneous use of both services, that were associated with more public health nursing visits, days in care, and use of all other health providers. The trend away from in-home nursing visits may create a situation of unmet need. While health and social resources are expended on persons with children with greater risk circumstances, the question remains about the efficacy and efficiency of this mix of service for parents and children receiving social assistance.

Adolescent↗