PubMed Health⌕ Search

Biomedical subjects

M E Gaulden

Publications and source records attributed to M E Gaulden.

26 records · Page 2Linked to original sources
PubMed1978

Use of the Y-body for identification of skin source on a successfully grafted burn patient.

The use of the interphase male Y-body (fluorescent Y chromosome segment) technique with cryostat sections of both fresh and frozen-stored skin biopsies is described. A female burn patient appeared to retain her donor homografts, thereby negating the need for autografts. Since a retained homograft of this sort challenged our understanding of immunologic barriers, we applied the Y-body technique to cutaneous biopsies obtained from the patient's burn area that had been homografted with skin from a male donor, as well as control biopsies from the patient's unburned skin and normal control male and female skin. Based on clinical and cytogenetic observations, it was concluded that the most reasonable explanation for this case was that the regenerating tissue at the graft site was that of the recipient and not that of the originally grafted male skin.

Burns↗
PubMed1971

The effects of varying concentrations of colchicine on the progression of grasshopper neuroblasts into metaphase.

The effects of four concentrations of colchicine (2.5 x 10(-7), x 10(-5), x 10(-3), and x 10(-2)M) on the cell cycle of grasshopper neuroblasts have been determined by direct observations on living cells. The lowest concentration, 2.5 x 10(-7)M, does not completely disorganize the spindle but does retard its action. The three higher concentrations disorganize the spindle, so that all cells reaching metaphase are blocked in a c-mitotic condition throughout the period of observations (308 min at 38 degrees C, the minimum duration of the cell cycle in untreated neuroblasts). Continuous treatment with all concentrations reduces the rate at which neuroblasts enter metaphase, the extent of the reduction being a function of increasing concentration and time of exposure. After a short exposure to 2.5 x 10(-5)M colchicine, the neuroblasts recover from the inhibiting effects on progression through the cycle to metaphase, but they show no recovery from the inhibiting effects on spindle formation for more than 3 hr. Apparent stimulation of progression rate occurs early in exposure to all concentrations and during recovery from a short exposure to 2.5 x 10(-5)M. Morphological alterations in the chromatin of telophase, interphase, and prophase cells are induced by the higher concentrations of colchicine. The data indicate that caution should be exercised in the use of colchicine for determining cell cycle duration and/or the effects of physical and chemical agents on the cycle.

Animals↗
PubMedDate not supplied

Preferential decrease in thymus dependent lymphocytes during storage at 4 C in anticoagulant.

Human lymphocytes stored at 4 C either as leukocyte concentrates (LCs) in citrate-phosphate-dextrose (CPD) or as whole blood anticoagulated with CPD show a rapid and marked decrease in the relative and absolute numbers of thymus derived (T) lymphocytes. Determinations were made on cells recoverable on a Ficoll-Hypaque (F-H) gradient. In evacuated LCs, the relative percentage of T cells dropped to less than 10 per cent within 72 hours with a concomitant increase in the relative percentage of bone marrow derived (B) cells to 80 per cent or more. LCs opened to the air and subsequently stored at 4 C displayed an even more precipitous decline in the relative percentage of T cells, reaching a 10 per cent level within 72 hours. The relative percentage of T cells in CPD-anticoagulated whole blood samples stored at 4 C displayed similar decreases, reaching 20 per cent levels within 24 hours. The change in the relative percentage of T cells at the Ficoll-Hypaque interface was shown to reflect a decrease in the total numbers of T cells placed on the F-H gradient with time, since determinations of T and B cell numbers in NH4Cl-treated whole blood showed a 65 to 80 per cent decrease in the numbers of T cells within 24 hours in anticoagulated whole blood held at 4 C. Thus, it may be inferred that the T cell decrease is mediated via some interaction of anticoagulant, storage time, and some component(s) present in both LCs and whole blood.

Anticoagulants↗