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D Amos

Publications and source records attributed to D Amos.

30 records · Page 2Linked to original sources
PubMed1987

Preparation of red-blood-cell-depleted marrow for ABO-incompatible marrow transplantation by density-gradient separation using the IBM 2991 blood cell processor.

Thirty patients who had major ABO blood group incompatibility with their HLA-matched donors underwent allogeneic marrow transplantation after removal of red blood cells (RBC) from donor marrow by Ficoll-Diatrazoate (F-D) separation using the IBM 2991 blood cell processor. We selected the IBM 2991 because we were interested in obtaining information about RBC-depleted mononuclear cells for monoclonal antibody and complement incubation of marrow. The median residual marrow RBC volume was 2.6 ml (1.2% of the original volume) and marrow infusion was well tolerated in every instance. The median doses of nucleated and mononuclear cells were 8.7 X 10(7)/kg and 2.2 X 10(7)/kg recipient weight, respectively, representing median marrow total nucleated and mononuclear cell losses of 63.4% and 52.9%, respectively. The median CFU-GM loss was 52.4%. Four patients died 13-21 days after marrow infusion and were unevaluable for engraftment. One patient failed to achieve engraftment and received a second transplant on day 36 from a second donor. One patient with myelofibrosis had poor engraftment and died on day 177 with low peripheral blood counts. For evaluable patients, no significant differences were observed in the rate of recovery of peripheral blood granulocyte or platelet counts between those receiving RBC-depleted marrow or ABO-matched unprocessed marrow. However, posttransplant red cell transfusion requirements were increased and transfusion independence delayed in patients receiving RBC-depleted marrow as compared to patients receiving unprocessed marrow. We concluded that red cell depletion using the IBM 2991 was effective in removing red cell, but resulted in significant and variable hematopoietic cell losses which may have contributed to graft failure in at least one patient. Such cell losses appear to be inherent in both manual and semiautomated methods for F-D cell separation.

ABO Blood-Group System↗
PubMed1986

Interstitial pneumonitis following autologous bone marrow transplantation.

The incidence of interstitial pneumonitis (IP) was reviewed in 70 consecutive patients who received autologous marrow transplants for hematologic malignancies. All patients were treated with total-body irradiation (TBI), with or without other chemotherapeutic agents. Seven patients (10%) developed IP, 3 were due to cytomegalovirus, 1 due to Pneumomcystis carinii, and 3 of unknown cause (idiopathic). Risk factors for developing IP were increasing age and a prior history of irradiation to the chest. The use of methotrexate posttransplant did not increase the incidence of IP.

Adolescent↗
PubMed1986

Hyperacute graft-v-host disease in patients not given immunosuppression after allogeneic marrow transplantation.

Sixteen patients with leukemia in relapse or second to third remission, 5 to 27 years old (median, 17), were given cyclophosphamide (60 mg/kg X 2) and total body irradiation (2.25 Gy for each of seven days) followed by unmodified marrow grafts from HLA-identical siblings. Patients did not receive posttransplant immunosuppression and were followed a median of nine months (range, 5-17). Prompt engraftment was sustained in 12 patients with a median time of 16 days (range, 10 to 63) to achieve 500 neutrophils/mm3. One patient failed to engraft, one had delayed engraftment, and two had late poor graft function. All 15 with engraftment developed moderate to life-threatening graft-v-host disease (GVHD, eight grade II and seven grade III-IV). This syndrome was hyperacute (median onset eight days [range, 7 to 29] posttransplant) and manifest by severe skin disease (14 patients at stage 3 and one at stage 4), fever (ten patients), and liver (four patients, stage 3-4) or gut (four patients, stage 3-4) involvement. Serial tissue biopsies confirmed acute GVHD in 13 of 15 patients. Ten were treated with antithymocyte globulin and cyclosporine (four survive), and four with corticosteroids (two survive). Actuarial survival to 17 months was 37%. Causes of death included interstitial pneumonia (four), infection (three), graft failure (one), venocclusive disease (one), and relapse of leukemia (one). Age-matched controls receiving standard methotrexate after transplant had comparable relapse-free survival but only a 25% incidence of grade II-IV acute GVHD (P less than .0001). We conclude that deleting posttransplant immunosuppression is associated with frequent and severe hyperacute GVHD, infectious complications, and occasional poor graft function.

Acute Disease↗
PubMed1986

Adverse effect of severe marrow fibrosis on hematologic recovery after chemoradiotherapy and allogeneic bone marrow transplantation.

We reviewed the records and marrow biopsy specimens of 75 patients with leukemic, myelodysplastic, or myeloproliferative disorders to determine whether the presence of marrow fibrosis affected engraftment after allogeneic marrow transplantation. While 28 control patients without fibrosis achieved prompt engraftment, two of 32 patients (6%) with mild and five of 15 patients (33%) with severe fibrosis failed. The rate of myeloid recovery was significantly slower and the dependence on platelet and red blood cell transfusions was significantly longer in patients with severe fibrosis than in patients with no fibrosis. A finding of severe marrow fibrosis should therefore be taken into account when evaluating the risks and benefits of marrow transplantation.

Adolescent↗
PubMed1986

Growth and development following marrow transplantation for leukemia.

One hundred forty-two patients between the ages of 1 and 17 years who survived disease-free more than 1 year after marrow transplantation for hematologic malignancy had growth and development evaluations from one to 14 years posttransplant (median 4 years). Prior to transplant all children received multiagent chemotherapy and 55 also received central nervous system irradiation, but none had growth and development evaluations. Marrow transplant preparation included high-dose chemotherapy and total body irradiation (TBI) given as a single dose of 9.2 to 10.0 Gy (79 patients) or as fractionated doses of 2.0 to 2.25 Gy/d for six to seven days (63 patients). After transplant abnormal thyroid function was present in 39%. Stimulated 11-desoxycortisol levels were subnormal in 24% of patients evaluated. Growth hormone (GH) deficiency was present in 17 of 25 children who received previous cranial irradiation. Partial GH deficiency was present in 4 of 25 who received previous cranial irradiation and in 6 of 18 who had not received cranial irradiation. Height velocity was decreased in all patients. After transplant, height was significantly influenced by chronic graft-v-host disease and single-dose TBI. Sixty-eight percent had delayed development of secondary sexual characteristics. Gonadal failure occurred in nearly all who were postpubertal at transplant. While it is not possible to determine how many of these endocrine abnormalities occurred as a result of treatment administered prior to transplantation, these data do demonstrate that children who become long-term survivors after marrow transplantation for hematologic malignancy have endocrine abnormalities that adversely affect growth and development.

Adrenal Cortex↗
PubMed1985

Marrow harvesting for autologous marrow transplantation.

The results and complications of 224 marrow collections from 200 patients with malignant disease who underwent marrow aspiration and storage for subsequent autologous marrow transplantation (AMT) were analyzed. The median age of the patients was 35 years (range 1-68); 131 patients had hematologic malignancies and 69 had solid tumors. Thirty-one patients proceeded directly to AMT after marrow aspiration at a median of 4.5 days (range 0-10). A further 75 patients received AMT a median of 3.0 months (12 days-10 years) after marrow aspiration. The remaining 94 patients had marrow stored but not infused. When a second aspiration was performed from the same patient within seven weeks, the yield of marrow nucleated cells was significantly reduced (p less than 0.02). A negative linear correlation was observed between CFU-C/kg harvested and the day to achieve a posttransplant blood neutrophil count greater than 500/cmm (r = -0.3092, p less than 0.05). A total of 36 (17.4%) complications associated with marrow aspiration were observed including two (0.97%) life-threatening episodes. Postoperative fever accounted for 23 of 34 episodes of minor complications. There was no increased risk of serious complications with decreased time from aspiration to transplant. It was concluded that the morbidity and mortality from autologous marrow aspiration did not differ significantly from that observed in normal donors.

Adolescent↗
PubMedDate not supplied

A coded histologic study of hepatic graft-versus-host disease after human bone marrow transplantation.

We tested the hypothesis that liver histology from patients with graft-versus-host disease could be distinguished from other common liver diseases. Liver biopsies from 33 allogeneic marrow transplant recipients with acute and chronic graft-versus-host disease and 37 nontransplant liver disease patients without graft-versus-host disease were recut, restained and coded for blind review. Analysis of individual histologic features showed significantly more cytologic aberration of bile duct epithelium and more cholestasis among biopsies with graft-versus-host disease when compared to biopsies without graft-versus-host disease (p less than or equal to 0.05). The duration of graft-versus-host preceding the biopsy influenced the histologic features. Biopsies before Day 35 showed frequent acidophilic bodies but infrequent bile duct changes. Biopsies from Days 35 to 90 posttransplant had more frequent bile duct exocytosis and disruption, and biopsies from patients with chronic graft-versus-host disease (beyond Day 90) showed more frequent portal fibrosis and bile duct dropout. Pattern assessment of coded biopsies showed that a histologic diagnosis of graft-versus-host disease had a positive predictive value of 86%, a sensitivity of 66% and a specificity of 91%. False-negative diagnoses occurred most frequently in biopsies obtained less than 4 weeks posttransplant, usually because bile duct abnormalities were not present. False-positive diagnoses of graft-versus-host disease occurred in nongraft-versus-host disease biopsies with periportal inflammation and proliferated bile ducts. However, biopsies of chronic graft-versus-host disease had more frequent dropout and disruption of bile duct epithelium than did biopsies of acute or chronic hepatitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy, Needle↗
PubMedDate not supplied

Smash the stereotypes.

Explore the source record for details and available documents.

Cultural Diversity↗
PubMedDate not supplied

An evaluation of staff nurse role transition.

This article summarises a study undertaken to examine the factors that influence role transition from student to staff nurse. It considers the impact of Project 2000 and reports on issues that enhance or inhibit role transition for newly qualified nurses. The study supports the UKCC's findings that students are able to question and evaluate practice, but do not feel they have the necessary clinical skills on qualifying. The evaluation showed that structured support is vital to assist role transition and can reduce anxiety and culture shock even in very busy areas. The participants identified that the newly acquired responsibility and accountability can be both enjoyable and threatening.

Adaptation, Psychological↗