Search PubMed⌕ Search

Biomedical subjects

A R Turner

Publications and source records attributed to A R Turner.

81 records · Page 5Linked to original sources
PubMedDate not supplied

Physical exercise and quality of life in cancer patients following high dose chemotherapy and autologous bone marrow transplantation.

Preliminary evidence indicates that physical exercise may be an effective strategy for the rehabilitation of cancer patients following high dose chemotherapy (HDC) and bone marrow transplantation (BMT), but the focus of this research has been on physical fitness and medical outcomes. In the present study, we employed a prospective design to examine the relationship between physical exercise and various quality of life (QOL) indices in 25 BMT patients. Participants completed weekly self-administered questionnaires upon being admitted to hospital, and monitored the frequency and duration of their exercise during hospitalization. Statistical analyses indicated that exercise during hospitalization was significantly correlated with almost all QOL indices, including physical well-being, psychological well-being, depression, anxiety and days hospitalized. Moreover, only some of the correlations were attenuated after controlling for relevant demographic and medical variables. It was concluded that physical exercise may be related to QOL in BMT patients, but that experimental research is needed before any definitive conclusions can be drawn.

Adult↗
PubMedDate not supplied

High dose misonidazole with dexamethasone rescue: a possible approach to circumvent neurotoxicity.

With a view to modifying misonidazole (MISO) neurotoxicity, we initiated a randomized clinical study to assess a possible drug interaction and toxicity protection when dexamethasone (DXM) is administered concomittantly with MISO. The ongoing study consists of: 1. Pharmacokinetic evaluation; 2. Assessment of toxicity. Fourteen patients undergoing radiation therapy for different types of malignant neoplasia (excluding brain tumors) have been randomized to receive either MISO alone, or DXM one week prior and during treatment with MISO. Five of seven patients receiving MISO alone developed peripheral neuropathies while only one out of 7 patients that received MISO with DXM coverage developed a transient and mild neuropathy. Pharmacokinetic evaluation of MISO in plasma and urine of those patients receiving DXM has shown no evidence of drug interaction. It is postulated that the mechanism of action of DXM is at the nerve cell membrane level, restoring and stabilizing cell surface properties. In future studies we will investigate the use of DXM with increasing doses of MISO above the recommended maximum dose of 12 gm/m2, hoping to achieve a higher tumor tissue level of MISO while avoiding unacceptable toxicity. The effect of Allopurinol on the plasma kinetics of MISO was studied in four additional patients, observing also no evidence of drug interaction.

Allopurinol↗
PubMedDate not supplied

Misonidazole enhances cyclophosphamide toxicity to bone marrow.

Normal bone marrow function was surveyed in animals that received cyclophosphamide after treatment with small, multiple doses of misonidazole. Peripheral blood white cell counts, cell differentials, hematocrits, bone marrow white cell counts and committed granulocyte-macrophage precursors (CFUc) were monitored for several days following treatment with misonidazole and cyclophosphamide. When results obtained from animals treated with physiological saline or misonidazole in advance of cyclophosphamide were compared, no significant differences were noted in routine assays of white blood cell count, cell morphology or hematocrit. Pre-treatment with misonidazole, however, caused a significant reduction in survival and delay in recovery of bone marrow CFUc (p less than .01). The combined use of misonidazole and cyclophosphamide also reduced animal survival (DMF = 1.2), with the majority of deaths being attributable to failure of normal hematopoietic function. These results suggest that misonidazole enhances the myelotoxicity associated with cyclophosphamide use. This additional damage is not detectable using routine hematological assays, but is demonstrable in assays of bone marrow stem cells and animal survival studies.

Animals↗
PubMedDate not supplied

Estimating the cost of expanding an apheresis program.

To determine the cost of expanding blood product operations, the concept of marginal cost must be used. This article reports the development and implementation of a method of costing increases in collecting plasma using apheresis operations. The model takes into account the fact that certain resource inputs--notably, direct labor and machines--increase in discrete steps rather than in a continuous manner. To address this fact, a stepwise cost analysis function was developed, which related operating costs to the volume of apheresis collections. This function was used to predict the marginal costs of potential increases in the supply of plasma at a blood center in Canada. Differences were noted in the cost of plasma in Canada and the United States, much of which could be attributed to different standards regarding the volume of plasma per collection and to differences in pricing materials.

Blood Banks↗
PubMedDate not supplied

Effect of misonidazole therapy on human granulopoietic stem cells.

Misonidazole is a 2-nitroimidazole compound currently being assessed as a radiosensitizing agent. The effects of misonidazole on human bone marrow hematopoiesis were assayed by culture of committed granulocyte-macrophage progenitor cells (CFU-C). Three groups of patients with nonhematologic malignancies were selected for study. The first group of patients received a single, large dose of misonidazole; the second group received smaller, multiple doses of misonidazole; and the third group who did not receive any misonidazole served as irradiation controls. In 14 of 16 patients who received single or multiple doses of misonidazole, there was a significant decrease in the number of CFU-C present in the bone marrow after misonidazole therapy. In five patients who received irradiation only, there was no difference in the number of pre- and post-treatment bone marrow CFU-C. In misonidazole treated patients, extensive washing of post-treatment bone marrow samples failed to return CFU-C growth to control values. Suppression of CFU-C growth persisted for 3 weeks and returned to control values by 8 weeks. This reduction in the proliferative capacity of human bone marrow progenitor cells suggests that misonidazole may add to the myelotoxicity already associated with radiotherapy, systemic chemotherapy, or as combination of the two.

Hematopoietic Stem Cells↗