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K Sheehan

Publications and source records attributed to K Sheehan.

27 records · Page 2Linked to original sources
PubMed1986

Decreased incidence of marrow graft rejection in patients with severe aplastic anemia: changing impact of risk factors.

Patients with severe aplastic anemia were conditioned with cyclophosphamide (200 mg/kg) and given marrow grafts from HLA-identical family members. Among 233 patients transplanted, 225 survived greater than or equal to 14 days and could be evaluated for engraftment. Forty-four of the 225 rejected their graft; 33 of these died and 11 survive. One hundred eighty-one patients had sustained engraftment; of these, 46 died and 135 survived. Binary logistic regression analyses revealed five risk factors for graft rejection: year of transplant, a large number of platelet transfusions, a positive relative response in mixed leukocyte culture, a low marrow cell dose, and omission of donor buffy coat cell infusion for transfused patients. These data show that patients transplanted recently had a lower likelihood of graft rejection than did patients transplanted in earlier years. Conceivably, this was related to changes in transfusion practices, but other factors as yet unidentified are likely to be involved. The data confirm that the largest possible number of marrow cells should be transplanted. Although the difference in the incidence of graft rejection between untransfused and transfused patients was not significant, it should be noted that transfused patients were given buffy coat cells. Because the addition of buffy coat cells results in a higher incidence of chronic graft-v-host disease (GVHD), it is still desirable to transplant patients with marrow alone early in their course before they have been transfused.

Anemia, Aplastic↗
PubMed1984

Cataracts after total body irradiation and marrow transplantation: a sparing effect of dose fractionation.

We examined 277 patients, who have been followed for 1 to 12 years after marrow transplantation, for cataract development. In preparation for transplantation, 96 patients with aplastic anemia were conditioned with chemotherapy only, usually cyclophosphamide 50 mg/kg X 4 intravenously, while 181 patients (two with aplastic anemia and 179 with a hematologic malignancy) were conditioned with a regimen of total body irradiation (TBI) and chemotherapy. TBI was delivered from two opposing 60Co sources at an exposure rate of 4 to 8 cGy/min, either as a single dose of 10 Gy (105 patients) or in fractions (76 patients), usually at increments of 2 to 2.25 Gy/day for 6 to 7 days for cumulative doses of 12 to 15.75 Gy. To date, 86 patients have developed cataracts. Kaplan-Meier product limit estimates of the incidence of cataracts for patients given chemotherapy only and no TBI, single-dose TBI, and fractionated TBI are 19, 80, and 18%, respectively. On the basis of proportional hazards regression analyses, patients given single-dose TBI had a relative risk of developing cataracts that was 4.7-fold higher than in patients given fractionated TBI or chemotherapy only (p less than 0.00005), suggesting a significant sparing effect with use of TBI dose fractionation. Addition significant risk factors included the chronic use of steroids posttransplant (highly associated with the presence of chronic graft-versus-host disease), and the diagnoses of acute lymphoblastic or chronic myelogenous leukemia.

Adolescent↗
PubMed1982

Prevention of water and heat losses from the exposed intestine.

Intestinal exposure results in increased evaporative water and heat losses. The losses are inversely proportional to ambient relative humidity. The purposes of this study were to quantitate water and heat losses from the exposed intestine and to test the plastic bag as a device to reduce these losses. Seventeen piglets were studied. Over a 2 hr period, evaporated losses were considerable--water 96 ml/m2 and heat 56 cal/m2. Prior to placing the intestine in a plastic nonpermeable bag, the exposed intestine lost 54.8 g/m2/hr at an ambient relative humidity of 41.3%. When the intestine was placed in a plastic bag, the relative humidity within the bag rose rapidly to 92.3% and evaporative water and heat losses fell to 0. It was concluded that placing the intestine in a plastic bag allowed the water vapor that escaped from the bowel surface to accumulate about the intestine, raising the relative humidity close to 100% and thereby markedly reducing further evaporation and water and heat losses.

Animals↗
PubMedDate not supplied

Late onset Alzheimer's disease and apolipoprotein association in the Irish population: relative risk and attributable fraction.

BACKGROUND: Familial and sporadic late onset Alzheimer's disease (LOAD) shows a consistent genetic association with APOE epsilon4. AIMS: To examine the role of APOE in the AD Irish population. METHODS: One hundred and ten Irish LOAD patients and 217 ethnically-matched controls were genotyped for APOE marker as described by Crook et al. Chi square test was used to compare allelic and genotypic frequencies between patients and controls samples. Attributable fractions were calculated as described by Levin. RESULTS: A highly significant association between AD and APOE epsilon4 was observed (chi2=37.9, p=0.0000000, RR=2.18). Further, the influence of APOEepsilon4 seems to follow a dose-dependent manner whereby individuals with the genotype APOEepsilon4/4 have a higher relative risk than those heterozygous for the epsilon4 allele (RR=4.03 and 1.76 respectively). The relative risk and the attributable fraction calculated for APOE epsilon4 are consistent with those reported for other European populations. This places the influence of this locus on AD development in the Irish population between those of the Spanish and New York white populations. CONCLUSION: These findings provide further evidence for the importance of APOE in the development of AD.

Aged↗