摘要:

AbstractThe effects of 1,4-bis(2'-chloroethyl)-1,4-diazabicyclo-[2.2.1] heptane diperchlorate (CBH; NSC 57198) on cell viability, growth, progression through the cell cycle, survival, and differentiation were investigated in suspension cultures of murine lymphocytic leukemia (L1210) and erythroleukemic (FL) cells and normal human lymphocytes stimulated with phytohemagglutinin (PHA) and in adherent cultures of Chinese hamster ovary (CHO) cells. CBH was equally cytotoxic toward stationary and exponentially growing CHO cells. Cell viability was diminished by 50% following 24 hr exposure to approximately 50μg CBH per ml. Treatment of quiescent human lymphocytes for 24 hr with up to 100μg CBH per ml did not appreciably diminish cell viability though the subsequent stimulation of such lymphocytes with PHA was inhibited in a dose dependent fashion. L1210, FL cells, and PHA stimulated human lymphocytes were equally sensitive to CBH, 50% inhibition of growth was obtained following 24 hr treatment with 25μg CBH per ml. Incubation for up to 48 hr with CBH did not result in differentiation of FL cells to mature hemoglobin containing cells. Constant exposure of L1210 cells and PHA-stimulated human lymphocytes to 10-50μg CBH per ml resulted in accumulation of cells in G2+ M phase; higher drug concentrations resulted in cell arrest in mid to late S phase and G2phase. A short 1-hr pulse of the drug resulted in a transient accumulation of L1210 cells in S and G2phases. However, cells recovered from a short pulse of drug and by 48 hr, both cell proliferation and the cell cycle distribution appeared normal. A detailed analysis of cell cycle progression of L1210 cells in the presence of the drug indicated that the duration of G2phase was extended at low concentrations (10μg/ml) while the transit of cells through S was retarded with subsequent accumulation in late S and G2phase at higher (50μg/ml) concentrations. Concomitant with cell arrest in S and G2phase an increase in cellular RNA content indicating unbalanced growth was observed. This state of unbalanced growth was reversible in cultures exposed to a 1-hr pulse of up to 100μg CBH per ml; cellular RNA content returned to control values by 48 hr. No effect on nuclear chromatin as assayed by acid denaturation was observed. Though the exact mechanism of drug action is not known, the data are not incompatible with the drug acting as an alkylating agent.

ISSN:0735-7907    

DOI:10.3109/07357908409020281

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

摘要:

AbstractMouse legs were irradiated to a dose of 30 Gy. After 50 days, when the acute reaction had regressed to a steady state, they were retreated with either various doses of x rays (15 to 30 Gy), hyperthermia, 45 min at 42.7°c, cis-DDP, or a combination of these agents. The maximum skin reactions and the skin reactions integrated over 50 days were determined. Statistical analysis of these data indicated the thermal enhancement ratio for the previously irradiated skin was approximately 1.20. The combination of x irradiation, hyperthermia, and cis-DDP treatments to the previously irradiated skin did not enhance the radiation damage beyond that produced by x irradiation and hyperthermia.

ISSN:0735-7907    

DOI:10.3109/07357908409020282

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

摘要:

AbstractThis paper describes the course of a patient with treated non-Hodgkin's lymphoma, which originally presented as a large nasopharyngeal mass. The tumor, though irradiated, recurred on two separate occasions in the right and left inguinal regions. At the time of tumor recurrence, markers were present which have been associated with past or recurrent Epstein-Barr virus (EBV) infection, namely, antibodies to the EBV viral capsid antigen (VCA) and the Epstein-Barr nuclear antigen (EBNA). EBNA was detected in approximately 10% of the neoplastic cells. An unusual immunoglobulin heavy and light chain switch within the tumor cells of the two separate inguinal node tumor recurrences was also observed. Whether EBV plays a role in the pathogenesis of lyphomas remains unclear.

ISSN:0735-7907    

DOI:10.3109/07357908409020283

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357908409020284

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357908409020285

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357908409020286

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357908409020287

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357908409020288

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor

ISSN:0735-7907    

DOI:10.3109/07357908409020289

出版商:Taylor&Francis    

年代:1984

数据来源: Taylor