Biomedical subjects

S A Sutherland

Publications and source records attributed to S A Sutherland.

4 recordsLinked to original sources

PubMed1991

Evaluation of anionic histological dyes as co-injectable cell markers in pre-implantation mouse embryos.

The enzyme horseradish peroxidase (HRP) is a widely used microinjectable cell marker for studying cell position, lineage, and migration in many kinds of animal embryos. Marked cells are easily identified because they darken when exposed to a chromophore and an HRP substrate such as hydrogen peroxide. This assay, however, requires cytochemical fixation. Thus, when HRP-marked cells need to be identified prior to fixation, visible co-injectants such as dyes and fluorescent substances have been used with HRP. Fluorescent substances have limitations because their excitation could be harmful to the marked cells. Visible but non-fluorescent co-injectants, however, would permit visualization of HRP-marked cells without inflicting such damage. We tested the compatibility of several histological dyes and electrolytic carriers with HRP iontophoresed as a cell marker in 2-cell mouse embryos. The dyes tested were Evans Blue, Cibacron Blue F3GA, Fast Green FCF, and Patent Blue Violet; the electrolytic carriers were KCl, K2SO4, CH3CO2K, and KH2PO4. The combination found most useful was Patent Blue Violet in K2SO4. Survival of embryos incubated to the blastocyst stage following injection with HRP + Patent Blue Violet in K2SO4 at the 2-cell stage was significantly greater than that of embryos injected with any other dye. Although the proportion of embryos undergoing the 8-cell-to-morula transition was somewhat decreased by this treatment, the proportion of embryos reaching the blastocyst stage was comparable to that in the uninjected (control) group. Our results indicate that Patent Blue Violet is a useful, HRP-co-injectable dye for short-term cell marking in preimplantation mouse embryos.

Animals↗

PubMed1979

Potential bacteremia in pediatric practice.

The potential consequences of bacteremia are considerable in all infants but particularly in those from 3 to 24 months of age with temperatures of 38.3 degrees C or more. Physicians have been advised to scrutinize these patients carefully with a variety of diagnostic tests and to treat their conditions vigorously if bacteremia is seriously considered or proved. We undertook to determine how often primary care pediatric practitioners encounter such patients "at risk" for bacteremia. Among the practices of nine pediatricians in Monroe County, New York, involving 220 practice days throughout 1977 and 4,151 patient visits, we found 145 instances of potential bacteremia. Depending, then, on the season of the year, practitioners may face this diagnostic and management dilemma as often as once each day. Therefore, laboratory means for determining those infants at highest risk for bacteremia or for rapidly diagnosing bacteremia will need to be readily available to practitioners.

Child, Preschool↗

PubMed1979

Collaborative research between a Department of Pediatrics and its clinical faculty.

Collaborative research involving members of the full-time and clinical faculties of a Department of Pediatrics increases our knowledge of problems encountered in primary care practice by bringing the practitioner's perspective on the nature of such problems and the population of patients he serves to the investigative arena. For the practitioner, active involvement in collaborative research is rewarding because he or she formulates the questions to be addressed and takes part in planning and implementing the research and reporting results. Through such collaboration, the academician gains immeasurably by being able to study common clinical problems in primary care settings, where they are encountered most often. To be successful, collaborative research must be a joint effort with ongoing communication and sharing of responsibilities between academicians and practitioners.

Faculty, Medical↗

PubMed1978

Primary pediatric care in one community.

Primary pediatric practice in one community was studied by using a household interview survey, a pediatrician mail questionnaire, and an ambulatory care survey of nine practices reporting on all visits over a four-week period. The results for the study year 1975 are compared with those for 1971 and 1967. Pediatricians provided an ever-increasing proportion of ambulatory care. Of all the children who had a regular physician in 1967, only 47% had a pediatrician; by 1975, this proportion had increased to 74%. Well-child care continues to be the largest diagnostic category (30%), followed by treatment for upper respiratory tract infections (24%), otitis media (14%), and lower respiratory tract infections (6%). Variations by practice and patient characteristics are examined. If the observed changes indicate a nationwide trend, a larger number of pediatricians will be needed to cover their growing share in primary care for children. Working in multiple settings and delegating part of the work load to nurse practioners have helped to meet the growing demand.

Adolescent↗