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R Clift

Publications and source records attributed to R Clift.

At least 37 records · Page 2Linked to original sources
PubMed1994

Cyclophosphamide combined with antithymocyte globulin in preparation for allogeneic marrow transplants in patients with aplastic anemia.

Graft rejection has been a problem after marrow grafts for patients with aplastic anemia who were conditioned with cyclophosphamide (CY). Rejection lessened when patients were given the marrow donor's peripheral blood buffy-coat cells in addition to the marrow, but this result was achieved at the price of more chronic graft-versus-host disease (GVHD). Results with second transplants suggested that CY alternating with antithymocyte globulin (ATG) was more immunosuppressive than CY alone. Therefore, the current study explored CY and ATG without buffy-coat cell transfusions in 39 patients with aplastic anemia given marrow transplants from HLA-identical family members (siblings in 38 cases, father in 1 case). We hoped both to minimize the risks of graft rejection and of chronic GVHD and to improve survival. Patients were 2 to 52 years of age (median, 24.5); 87% had received previous transfusions, and 41% had therapy with immunosuppressive agents before transplant. They were administered four daily doses of CY (total, 200 mg/kg) alternating with three doses of ATG (total, 90 mg/kg) followed by an HLA-identical marrow graft. Methotrexate and cyclosporine were administered to prevent GVHD. Two patients rejected their grafts (5%), and both were successfully retransplanted. Acute (grade 2 or 3) GVHD occurred in 15% and chronic GVHD in 34% of patients. The actuarial survival rate at 3 years was 92%, which compares favorably to the 72% survival rate in 39 historical patients who were matched with current patients for age and risk factors for rejection and GVHD. CY/ATG is a well-tolerated and effective conditioning program for marrow grafting in aplastic anemia that, when combined with GVHD prevention by methotrexate/cyclosporine, results in excellent survival.

Adult↗
PubMed1994

Randomized study of the effect of midnight removal of urinary catheters.

This study shows that removal of urinary catheters at midnight has several advantages over removal at 6 AM. The midnight group had a significantly greater initial voided volume and a longer time to first void than the equivalent 6 AM group. Advantages to midnight catheter removal also exist for nursing staff. Midnight tends to be less busy on the nursing unit compared with 6 AM, thus making it a preferable time for performance of routine tasks. Catheter removal at midnight also allows for convenient observation of patient voiding and assessment earlier in the day. This means that any necessary intervention can take place during working hours when more staff are on duty. There is also the potential for earlier discharge, with economic benefits related to shorter bed stay and more efficient discharge planning. We believe midnight catheter removal offers considerable benefits over the traditional 6 AM time on both general and urology units.

Female↗
PubMed1993

Autologous transplantation with peripheral blood mononuclear cells collected after administration of recombinant granulocyte stimulating factor.

Peripheral blood mononuclear cells (PBMC) were collected after the administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and used as the sole source of hematopoietic stem cells after myeloablative therapy with busulfan (Bu) and cyclophosphamide (Cy). These studies were performed in 12 patients with malignancies (4 non-Hodgkin's lymphoma, 5 breast cancer, 1 testicular carcinoma, 1 Wilm's tumor, and 1 undifferentiated carcinoma) who had bone or bone marrow disease or had low marrow cellularity. rhG-CSF (16 micrograms/kg/d) was administered for 5 to 7 days by subcutaneous injection and PBMC were collected for 2 to 5 days beginning on day 4 after initiation of rhG-CSF, using continuous-flow blood-cell separators that processed 10 to 12 L of whole blood. From a median of three collections, a mean of 24.0 x 10(8) (+/- 10.5 SD) total nucleated cells/kg containing 12.6 x 10(8) (+/- 4.5 SD) mononuclear cells/kg, 7.3 x 10(6) (+/- 4.3 SD) CD34+ cells/kg and 20.5 x 10(4) (+/- 28.1 SD) granulocyte-macrophage colony-forming units (CFU-GM)/kg were harvested and cryopreserved. After the administration of Bu 14 to 17 mg/kg and Cy 120 to 150 mg/kg, PBMC were thawed and infused. One patient received rhG-CSF after the infusion of PBMC and the remaining 11 patients did not receive postinfusion growth factors. Mean days to recovery of neutrophil levels of 0.1, 0.5, and 1.0 x 10(9)/L were 11.4 (range, 9 to 13), 12.7 (range, 10 to 15), and 13.6 (range, 11 to 16) and the mean day to platelet transfusion independence was 13.3 (range, 7 to 49). Time to recovery of neutrophils to 0.5 and 1.0 x 10(9)/L and platelets to 20 x 10(9)/L was more rapid than in historical patients treated with Bu and Cy who received marrow alone or marrow followed by the posttransplant administration of rh-G or GM-CSF. No graft failures have been observed with a follow-up of 4 to 12 months. These results indicate that PBMC collected after rhG-CSF lead to rapid hematopoietic recovery after myeloablative chemotherapy.

Antigens, CD↗
PubMed1993

The effects of daily recombinant human granulocyte colony-stimulating factor administration on normal granulocyte donors undergoing leukapheresis.

The effects of daily administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) to eight normal volunteers donating granulocytes for neutropenic relatives undergoing marrow transplantation were studied. Granulocyte donors consisted of seven marrow donors (5 syngeneic, 2 HLA identical) and one haploidentical son who had not donated marrow. All donors were administered daily rhG-CSF at a mean dose of 5 micrograms/kg/d (range 3.5 to 6.0) for a mean of 11.75 days (range 9 to 14 days), and granulocytes were collected a mean of 7.6 times (range 4 to 12). RhG-CSF was well tolerated and only minor side effects were observed. All donors became anemic from marrow donation and the removal of red blood cells during the collection procedures. Red blood cell transfusions were not given. All donors had a decrease in platelet counts and the magnitude of the decrement appeared to be greater than in historical donors. This was due in part to increased removal of platelets with the collection product, but a direct effect of rhG-CSF on platelet production cannot be excluded. The mean precollection granulocyte level was 29.6 x 10(9)/L (range 11.8 to 79.8), which was a 10-fold increase over baseline. The mean number of granulocytes collected was 41.6 x 10(9) (range 1.3 to 144.1), which was a six-fold increase over historical donors not receiving rhG-CSF. The mean granulocyte level 24 hours after transfusion into neutropenic recipients was 0.95 x 10(9)/L (median 0.57 and range .06 to 9.47). This study indicates that rhG-CSF is safe to administer to normal individuals, significantly improves the quantity of granulocytes collected, and results in significant circulating levels of granulocytes in neutropenic recipients. Further studies to evaluate rhG-CSF in normal granulocyte donors are warranted.

Adult↗
PubMed1993

Assessment of the suitability of commercially available SpA affinity solid phases for the purification of murine monoclonal antibodies at process scale.

Eight commercially available staphylococcal protein A (SpA) affinity chromatography solid phases were evaluated in order to establish their potential for the large-scale purification of a murine monoclonal antibody (MAb, mIgG1). The antibody was produced in-house, serum-free, in a hollow fibre bioreactor. Solid phases were tested for the effects of salt concentration, pH, and the presence of MAb on ligand leakage and flow rate. These effects were compared using the solid phases in stirred-tank (roller-mixing) and flow-through (packed-bed) modes of operation. Ligand leakage in the absence of MAb was generally at its lowest when the solid phases were used in a flow-through mode. In this mode of operation increasing the inorganic salt concentration and pH of the washing/adsorption buffer from 150 mM at pH 8.6, to 3 M at pH 8.9, typically produced a 10% increase in MAb capacity of the solid phases (20% for Sepharose CL-4B). However, contamination of the purified antibodies was also greatly increased due to an elevated level of background ligand leakage from the matrices. Residual contaminating levels of SpA in affinity purified MAbs were lowest with a low salt (NaCl, 150 mM) glycine (1 M) adsorption/washing buffer. Maximal antibody capacity was achieved for all matrices on frontal analysis (breakthrough curves), as opposed to a pulse mode of use. The largest capacity was found for Prosep A 'high capacity' (12-15 mg/ml column volume), where capacity approached its experimentally determined theoretical capacity (C/Co = 0.5) regardless of its mode of use. The relatively high MAb capacity of Prosep A 'high capacity' was further reflected in a superior dynamic isotherm. Frontal analysis, however, generally resulted in a greater SpA contamination of the purified MAbs. Under these conditions the lowest levels of SpA contamination were found for the Prosep A 'high capacity', and Repligen solid phases (12 ppm) on purifying 12.8 and 4.3 mg of MAb respectively. For the large scale downstream processing of a MAb for therapeutic applications, Prosep A 'high capacity', would appear to be the most appropriate of the solid phases tested.

Animals↗
PubMed1993

Randomised study of the effect of midnight versus 0600 removal of urinary catheters.

A randomised controlled trial was undertaken to determine the effects of midnight removal of urinary catheters on patients' voiding patterns and subsequent discharge from hospital. Patients whose urinary catheters were removed at midnight showed a greater volume of initial void than those whose catheters were removed at the usual time of 0600. Removal of urinary catheters routinely at midnight permits earlier assessment of patients' voiding, which may allow for earlier discharge from hospital.

Humans↗
PubMed1993

High-dose cyclophosphamide, carmustine, and etoposide followed by autologous bone marrow transplantation in patients with lymphoid malignancies who have received dose-limiting radiation therapy.

PURPOSE: To evaluate high-dose chemotherapy followed by autologous bone marrow transplantation (ABMT) in patients with lymphoid malignancy who had received prior radiation therapy. PATIENTS AND METHODS: Fifty-seven patients with non-Hodgkin's lymphoma (NHL; n = 23), Hodgkin's disease (HD, n = 32), or acute lymphoblastic leukemia (ALL; n = 2) with a history of previous radiation therapy were treated with cyclophosphamide (Cy; 7.2 g/m2), carmustine (300 mg/m2 or 600 mg/m2), and etoposide (2,400 mg/m2) (CBV) followed by ABMT. RESULTS: The projected 2-year probabilities of survival, event-free survival (EFS), and relapse were .31, .24, and .76, respectively. For patients with intermediate- and high-grade lymphoma and HD the probabilities were .27, .10, and .14 for EFS and .57, .90, and .77 for relapse. The probability of nonrelapse mortality in the first 100 days post-ABMT was 33%. Idiopathic pneumonia syndrome (IPS) was observed in no patients who received carmustine 300 mg/m2 and 23% of patients who received carmustine 600 mg/m2 (P = .05). Eight-three percent of patients who received mediastinal radiation therapy less than 3 months before transplant developed IPS, compared with 13% who received radiation therapy more than 3 months before transplant (P = .001). CONCLUSION: ABMT following high-dose CBV resulted in long-term disease-free survival in 25% of patients with lymphoid malignancies who had previously received dose-limiting radiation therapy. Fatal IPS and a high relapse rate were major factors limiting successful outcome following ABMT. The morbidity and mortality rates associated with the administration of carmustine 600 mg/m2 were prohibitively high, especially in patients who received mediastinal radiation immediately before ABMT, and were not associated with a decrease in post-ABMT relapse.

Adolescent↗
PubMed1993

Altered platelet indices in dogs with hypothyroidism and cats with hyperthyroidism.

Changes in platelet indices (platelet count and platelet size) and PCV associated with thyroid disease were studied in 7 dogs with hypothyroidism and 21 cats with hyperthyroidism that were admitted to the veterinary teaching hospital. Compared with control (euthyroid) dogs, dogs with hypothyroidism had higher platelet count (P = 0.003), smaller platelet size (P = 0.01), and lower PCV (P = 0.02). Comparison of the group of hyperthyroid cats with a group of similarly aged, clinically normal cats with normal thyroxine values indicated that the group of hyperthyroid cats had significantly (P = 0.03) higher mean platelet size than did control cats, but differences were not found in mean platelet count or PCV. Results of this investigation indicate that the changes in platelet size reported in human beings with thyroid endocrinopathies also are found in animals so-affected. Although the pathogenesis of platelet abnormalities in animals with thyroid derangement is unclear and likely is multifactorial, the observed relation between platelet and erythrocyte production in this group of dogs is consistent with reports of an inverse relation between thrombocytopoiesis and erythropoiesis in iatrogenically hyperthyroid mice and in mice exposed to hypoxia.

Animals↗
PubMed1993

Consequences of cryopreserving first remission autologous marrow for use after relapse in patients with acute myeloid leukemia.

Ninety-eight patients with AML had marrow harvested and cryopreserved at a median of 6 months (range 1-36 months) after achieving first CR with the intent of performing an ABMT at the first sign of relapse. Thirty-three of the 98 patients have not relapsed and 32 survive at a median of 64 months (range 10-105 months) after marrow storage. Sixty-five of the 98 patients relapsed at a median of 7 months (range 1-53 months) after marrow storage. The survival at 2 and 4 years for the 65 patients who relapsed was 22% and 8% respectively. Sixteen of 24 patients treated initially with chemotherapy were ultimately transplanted and two are surviving 21 and 41 months following ABMT and allogeneic marrow transplant respectively. There were no survivors among the eight patients treated with chemotherapy who were not transplanted. Thirty-eight of the 65 patients who relapsed proceeded directly to ABMT without attempts at remission induction, and eight survive disease-free 15-114 months following ABMT. One of the first 17 patients treated with cyclophosphamide and total body irradiation survives without relapse. The probabilities of relapse-free survival, non-relapse mortality, and relapse for the 17 most recent patients prepared with busulfan-containing regimens were 41%, 39% and 32% respectively. Surviving patients had longer first remissions (p = 0.08) and lower peripheral blood blast counts at the time of transplant (p = 0.02) when compared with patients who died. These data suggest that ABMT in untreated first relapse is a reasonable approach for the treatment of patients with AML who relapse.

Adolescent↗
PubMed1992

A sensitive enzyme-linked immunosorbent assay (ELISA) for the detection of staphylococcal protein A (SpA) present as a trace contaminant of murine immunoglobulins purified on immobilized protein A.

A specific non-competitive enzyme-linked immunosorbent assay (ELISA) has been developed for detecting and quantifying protein A (SpA), present as a trace contaminant of therapeutic murine monoclonal antibodies (McAb) purified on immobilized SpA preparations. The assay employs a microtitration plate system, in which affinity-selected chicken anti-SpA antibodies from the egg yolks of immunized hens provide a specific capture antibody, followed by the addition of standards or sample with a McAb concentration of 1 mg/ml, in conditions unfavourable for Fc binding, and finally an affinity-selected rabbit anti-SpA peroxidase label. The working range of this assay is between 0.5 and 10.0 ng/ml (CV less than 5%), with a lower limit of detection of 0.2 ng/ml (CV less than 10%). This assay was used to evaluate SpA leakage when purifying a serum-free murine IgG1 cell culture supernatant using SpA immobilized on agarose (Protein A-Sepharose CL-4B) or controlled pore glass (Prosep A, high capacity). These gave average antibody SpA contamination levels of 6.7 +/- 1.6 and 2.4 +/- 0.5 (mean +/- SD) parts per million respectively.

Animals↗
PubMed1989

Methotrexate and cyclosporine versus cyclosporine alone for prophylaxis of graft-versus-host disease in patients given HLA-identical marrow grafts for leukemia: long-term follow-up of a controlled trial.

Patients with acute nonlymphoblastic leukemia (ANL) in first remission (n = 38) or chronic myelocytic leukemia (CML) (n = 55) were given cyclophosphamide and total body irradiation, followed by marrow infusion from HLA-identical siblings. To evaluate postgrafting prophylaxis for acute graft-versus-host disease (GVHD), the patients were randomized to receive either methotrexate and cyclosporine (n = 43) or cyclosporine alone (n = 50). Methotrexate/cyclosporine significantly reduced the incidence and severity of acute GVHD, and improved early survival. This report updates the results with a 3.0 to 4.5 year follow-up. Methotrexate/cyclosporine did not interfere with sustained hematopoietic engraftment, although granulocyte recovery to 1,000/microL was delayed by five days on the average. The incidence of chronic GVHD was identical in the two groups (26% v 24%). Disease-free 3-year survival was slightly better in the methotrexate/cyclosporine group (65% v 54%), but this benefit was restricted to patients with CML (73% v 54%), while no improvement was seen in patients with ANL (41% v 41%). In contrast to patients with CML (relapse rates 8% v 9%), the early survival benefit among patients with ANL given methotrexate/cyclosporine was offset by an increase in leukemic relapses (29% v 16%).

Acute Disease↗
PubMed1989

Effect of HLA compatibility on engraftment of bone marrow transplants in patients with leukemia or lymphoma.

We analyzed the relevance of HLA compatibility to sustained marrow engraftment in 269 patients with hematologic neoplasms who underwent bone marrow transplantations. Each patient received marrow from a family member who shared one HLA haplotype with the patient but differed to a variable degree for the HLA-A, B, and D antigens of the haplotype not shared. These 269 patients were compared with 930 patients who received marrow from siblings with identical HLA genotypes. All patients were treated with cyclophosphamide and total-body irradiation followed by the infusion of unmodified donor marrow cells. The rate of graft failure was 12.3 percent among the recipients of marrow from a donor with only one identical haplotype, as compared with 2.0 percent among recipients of marrow from a sibling with the same HLA genotype (both haplotypes inherited from the same parents) (P less than 0.0001). The incidence of graft failure correlated with the degree of donor HLA incompatibility. Graft failure occurred in 3 of 43 transplants (7 percent) from donors who were phenotypically HLA-matched with their recipient (haplotypes similar, but not inherited from the same parents), in 11 of 121 donors (9 percent) incompatible for one HLA locus, in 18 of 86 (21 percent) incompatible for two loci, and in 1 of 19 (5 percent) incompatible for three loci (P = 0.028). In a multivariate binary logistic regression analysis, independent risk factors associated with graft failure were donor incompatibility for HLA-B and D (relative risk = 2.1; 95 percent confidence interval, 1.7 to 2.5; P = 0.0004) and a positive crossmatch for anti-donor lymphocytotoxic antibody (relative risk = 2.3; 95 percent confidence interval, 1.8 to 2.8; P = 0.0038). Residual host lymphocytes were detected in 11 of 14 patients with graft failure, suggesting that the mechanism for graft failure could be host-mediated immune rejection. We conclude that donor HLA incompatibility and prior alloimmunization are significant risk factors for graft failure, and that a more effective immunosuppressive regimen than those currently used is needed for consistent achievement of sustained engraftment of marrow transplanted from donors who are not HLA-identical siblings.

Adolescent↗
PubMed1989

Graft-versus-host disease prevention by methotrexate combined with cyclosporin compared to methotrexate alone in patients given marrow grafts for severe aplastic anaemia: long-term follow-up of a controlled trial.

Forty-six patients with aplastic anaemia (median age 23 years) were given cyclophosphamide followed by infusion of marrow from an HLA-identical family member. To evaluate postgrafting prophylaxis for graft-versus-host disease (GVHD), the patients were entered into a randomized prospective trial comparing a combination of methotrexate and cyclosporin (n = 22) to methotrexate alone (n = 24). Methotrexate/cyclosporin significantly reduced the incidence and severity of acute GVHD and improved early survival. This report updates the results of the randomized trial with followup ranging from 3 to more than 6 years. The methotrexate/cyclosporin regimen did not interfere with sustained engraftment, and there were no significant differences in the incidence of early or late graft rejection among the two treatment groups (10% v 4%). The incidence of chronic GVHD was higher among methotrexate/cyclosporin-treated patients (58% v 36%; P = 0.18). Two patients in each treatment group still require treatment for chronic GVHD, while treatment is no longer needed in the other patients. Projected 4-year survival is 73% in patients given methotrexate/cyclosporin compared to 58% in patients given methotrexate alone (P = 0.16). Having achieved a reduction in the incidence of acute GVHD and associated early mortality without impairing engraftment, it is clear that future progress in marrow grafting for aplastic anaemia must come in the area of chronic GVHD.

Adolescent↗