摘要:

AbstractCombined total body irradiation (TBI) and Prednimustine were prospectively evaluated in 30 patients affected either with chronic lymphocytic leukemia (CLL) or with low-grade non-Hodgkin's lymphoma (NHL) eleven patients were previously treated. Between January 1984 and May 1987, 20 evaluable patients with CLL, median age 66 years (range 43–82), classified according to Rai (4 in stage I, 10 in stage II, 4 in stage III, 2 in stage IV) and 10 evaluable patients with NHL low-grade malignancy according to the Working Formulation, Stages III and IV, median age 54 years (range 32–71) were treated using a 6 MeV Linear Accelerator, applying two opposite alternating fields including total body, with a fraction of 15 cGy, 2 fractions weekly (3-day interval) for a total dose of 150 cGy given over 5 weeks. Prednimustine (100 mg/m2, orally, for 5 consecutive days, every 3–4 weeks, for 6–9 courses) was administered 2 months after TBI treatment, as consolidation therapy. By May 1989, a total of 85% hematological responses (defined as normalization of the differential white cell count, of the total blood cell count and of bone marrow infiltration) were obtained after combined treatment in CLL patients; moreover 3 CR (according to the WHO criteria), 75% with splenomegaly reduction and 40% with lymphadenopathy reduction were seen. Ninety percent objective responses (5 CR and 4 PR) were observed in the NHL patients, with 50% having splenomegaly reduction and 67% lymphadenopathy reduction. The median response time in the two groups was, respectively, 14 and 23 months. The overall toxicity (WHO grades 1,2,3,4) after combined treatment was 65% and 70% in the two patient groups. WHO grade III toxicity, completely reversible, was verified in only 16.6% of the cases; all cases, except one, were previously treated. Additionally, 1 toxic death (grade IV thrombocytopenia and leukopenia) was observed in a heavily pretreated patient affected with CLL after TBI alone. Prednimustine regimen was generally well tolerated. The high response rate and acceptable toxicity, confirms the feasibility and the usefulness of TBI in the context of a combined treatment for CLL and low-grade NHL patients. However in order to further reduce the severe toxic side effects, observed in one patient, white blood cells and platelet count should be plotted and monitored carefully, particularly in pretreated patients.

ISSN:0735-7907    

DOI:10.3109/07357909109084637

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractIn this study, the relationship between the dCTP/ara-CTP ratio and the cytotoxic effect of cytosine arabinoside (ara-C) was investigated. Intracellular levels of dNTPs and ara-CTP were analyzed by high-performance liquid chromatography. Although doubling time and intracellular dCTP levels were different in each of the cells, there was a consistent relation between the intracellular dCTP/ara-CTP ratio and the cytotoxic concentration of ara-C. These data suggest that the intracellular dCTP/ara-CTP ratio is one of the important factors for considering the cytotoxic action of ara-C.

ISSN:0735-7907    

DOI:10.3109/07357909109084638

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractPolyamines are essential for cell growth of normal and neoplastic tissue.α-Difluoromethylornithine (DFMO) is a known irreversible inhibitor or ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis. The purpose of this study was to examine the effects of tumor burden on ODC in tissues of tumorbearing compared with tumor-free mice. Twenty-eight male Balb/c mice were divided into four groups of 7 each. Groups 1 and 2 were inoculated subcutaneously with 10 X 106MC-26 mouse colon adenocarcinoma cells. Groups 3 and 4 were kept as tumor-free controls. Ten days after inoculation, groups 2 and 4 were injected with DFMO (200 mg/kg) intraperitoneally (IP) while Groups 1 and 3 received saline. Two hours after the injection of DFMO the animals were sacrificed. The tumor, pancreas, kidney, and liver were excised and analyzed for ODC activity. DFMO caused a significant reduction (compared with controls that did not receive DFMO) in the ODC activity of tumors; however, ODC activity of the kidney, pancreas, and liver of tumor-bearing mice was not affected. Additionally, the basal ODC activity in the kidney, liver, and pancreas of tumor-bearing mice was significantly lower compared with tumor-free controls. DFMO lowered ODC activity in the kidney, pancreas, and liver of tumor-free mice. These results suggest that the presence of MC-26 tumor causes systemic effects that alter ODC activity and the response to a known inhibitor of ODC.

ISSN:0735-7907    

DOI:10.3109/07357909109084639

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractBlood levels of selenium, zinc, copper, and vitamins E and C were measured in 48 cases and 50 controls from a hospital-based case-control study bearing on breast cancer risk factors in Montpellier (France). Cellular levels of selenium and vitamins E and C were also evaluated in most of the subjects. We found that the blood and cellular levels of these antioxidants were overall higher in cases than in controls, significantly for serum zinc, plasma, and leukocyte vitamin E. The statistical significance of the difference between case and control serum Cu crude levels disappeared after adjustment for metabolically related variables. The difference was borderline significant for leukocyte vitamin C. These results were slightly modified when vitamin pill users were excluded from case and control samples. The serum zinc odds ratios computed after adjustment for related variables were significantly elevated (2.53, confidence interval: 1.34–4.78, for the highest tertile) as were those computed previously for pooled plasma vitamin E levels in a joint study.

ISSN:0735-7907    

DOI:10.3109/07357909109084640

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357909109084641

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357909109084642

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357909109084643

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357909109084644

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractRadiation treatment planning is currently in a state of rapid change. Dissatisfaction with past planning technology stems from the growing realization that: (1) Increases in the local regional tumor control rate will increase the cure rate in many malignancies. (2) Even at the best treatment centers geometric tumor misses are commonplace. (3) Traditional constraints on treatment techniques, originally imposed for simplicity and reproducibility, are no longer necessary, and can result in suboptimal treatment. (4) Treatment plans judged“optimal”in two dimensions may be far from optimal when viewed over the entire treatment volume. (5) Lack of treatment reproducibility is also commonplace, and can be demonstrated to adversely affect treatment outcome. On the positive side, recent developments in computer graphics, image processing, radiation physics, and radiation biology are now making it possible to define, design, and deliver sophisticated 3D radiation treatments. However, because many of these technologies are being developed for other disciplines, their applicability to radiation therapy treatment planning is not widely appreciated. We outline the current status and new developments in radiation therapy treatment planning.

ISSN:0735-7907    

DOI:10.3109/07357909109084645

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357909109084646

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor