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1.
Summary Animals bearing the passable plasmacytoma MOPC 104E could be cured of palpable tumors (0.6–2.0×108 cells) with single 10–250 mg/kg doses of cyclophosphamide or single localized x-ray doses greater than 1600 R. Residual tumor immunity of cured animals was determined by their ability to reject graded numbers of viable MOPC 104E cells 30 days following curative therapy. High doses of cyclophosphamide (250 mg/kg), although curative, left significantly less residual tumor immunity than either low dose cyclophosphamide (10 mg/kg) or localized irradiation. Animals cured of palpable tumors by high doses of cyclophosphamide nonetheless rejected greater numbers of cells in secondary challenge than did untreated control animals.This investigation received support from NIH Grants 13371, 17065, 05136, and 09082 from the National Cancer InstituteSubmitted in partial fulfilment of the degree Doctor of Philosophy in Radiation Biology  相似文献   

2.
Freeze-dried Bacillus Calmette Guerin (B.C.G.) of Institut Pasteur was given by intravenous route to mice at 1,2 and 4 mg/kg before and after gamma irradiation of animals by 1 000 rad. B.C.G. 1 mg/kg injected the day or the day after irradiation has a protective effect (mortality reduced from 77% for controls to 58% and 50% for treated mice). B.C.G. given before irradiation in single or double doses increased mortality.  相似文献   

3.
The aminophosphorothioate WR-3689 was characterized for its ability to protect mouse jejunal cells in vivo from single doses of X or gamma radiation. First, the effect of the drug on the survival of jejunal stem cells was examined using a clonogenic end point, the crypt microcolony assay. When WR-3689 was administered 30 min prior to whole-body irradiation, the number of surviving crypt cells was markedly increased at all doses of the drug, although protection began to level out at doses larger than 600 mg/kg. Protection was maximal when the drug was given 30 min before whole-body irradiation and declined rapidly with both shorter and longer intervals. Protection factors (PFs) were obtained by measuring survival curves for clonogenic crypt cells as a function of radiation dose; WR-3689 given 30 min before whole-body irradiation protected jejunum in the microcolony assay with a PF of 1.26 +/- 0.02, 1.50 +/- 0.10, and 1.65 +/- 0.10 at doses of 200, 400, and 800 mg/kg, respectively. Next, the effect of WR-3689 on the survival of jejunal stem cells was determined by assaying the survival of mice given X-ray doses to the whole abdomen in the range leading to death from the gastrointestinal syndrome. The PFs based on the LD50 values for 11-day survival were 1.31 +/- 0.05 (200 mg/kg) and 1.48 +/- 0.05 (400 mg/kg). Crypt-cell survival and animal survival were thus modified to a similar extent by this agent. Finally, the effect of WR-3689 on the induction of DNA single-strand breaks (SSBs) in jejunal cells was measured using an adaptation of the alkaline elution methodology. In mice treated with WR-3689 (400 or 800 mg/kg) 30 min prior to whole-body irradiation with 10 Gy there was no significant reduction in the number of DNA SSBs induced either in samples of the jejunum or in the cycling crypt cells, providing further evidence that there is no simple relationship between the modification of DNA SSBs and the survival of jejunal stem cells.  相似文献   

4.
Cytogenetic analysis and the micronucleus test of bone-marrow cells was used to study the possible extrapolation of results from experimental animals to man.Cytembena was given i.p. in doses of 5, 10, 20, 40 and 80 mg/kg body wt. to Wistar rats in doses of 20, 40 and 80 mg/kg body wt. to ICR mice an dto Chinese hamsters. Five patients with various types of malignancy, so far medically untreated, received 20 mg Cytembena/kg body wt i.v.A combination of Cytembena and cylophosphamide was applied i.p. in single equal doses 1 : 1 of 5, 10, 20, and 40 mg/kg body wt to ICR mice, Chinese hamsters and Wistar rats. Patients were given i.v. 20 mg Cytembena and 20 mg cyclophosphamide/kg body wt.Bone-marrow cells were examined 24 h after the administration.The frequency of abnormal metaphases and chromosomal breaks after Cytembena treatment was low; nonetheless, the indicated dose-effect relationship was found in all the rodents used. The frequency of chromosomal breaks was 2–3 times higher in rodents in comparison with man, after treatment with a dose of 20 mg Cytembena/kg body wt.Highest frequencies of induced aberrations were found in mice. The rodents appeared to be 3–4 times more sensitive to the induction of chromosomal breaks and abnormal metaphases than man, after a dose of 20 mg Cytembena and 20 mg cyclophosphamide/kg body wt.  相似文献   

5.
In vivo postirradiation protection by a vitamin E analog, alpha-TMG   总被引:2,自引:0,他引:2  
The water-soluble vitamin E derivative alpha-TMG is an excellent radical scavenger. A dose of 600 mg/kg TMG significantly reduced radiation clastogenicity in mouse bone marrow when administered after irradiation. The present study was aimed at investigating the radioprotective effect of postirradiation treatment with alpha-TMG against a range of whole-body lethal (8.5-12 Gy) and sublethal (1-5 Gy) doses of radiation in adult Swiss albino mice. Protection against lethal irradiation was evaluated from 30-day mouse survival and against sublethal doses was assessed from micronuclei and chromosomal aberrations in the bone marrow 24 h after irradiation. An intraperitoneal injection of 600 mg/kg TMG within 10 min of lethal irradiation increased survival, giving a dose modification factor (DMF) of 1.09. TMG at doses of 400 mg/kg and 600 mg/kg significantly reduced the percentage of aberrant metaphases, the different types of aberrations, and the number of micronucleated erythrocytes. DMFs of 1.22 and 1.48 for percentage aberrant metaphases and 1.6 and 1.98 for micronuclei were obtained for 400 mg/kg and 600 mg/kg TMG, respectively. No drug toxicity was observed at these doses. The effectiveness of TMG when administered postirradiation suggests its possible utility for protection against unplanned radiation exposures.  相似文献   

6.
Previous studies from our laboratory have suggested that, in addition to an effect on spermatozoa in the testis, cyclophosphamide may have an adverse effect on spermatozoa after they leave the testis, during epididymal transit. To elaborate on this post-testicular effect on germ cells and to determine at which site(s) in the epididymis germ cells are most sensitive to cyclophosphamide treatment, three experiments were undertaken. First, the time course of the effect of treatment of male rats with cyclophosphamide on the outcome of their progeny was determined. Male rats were treated daily by gavage with saline or one of two doses of cyclophosphamide (6.8 mg/kg or 10.0 mg/kg) for 1, 4, or 7 days. At the end of each treatment period, males were mated to assess the effect on pregnancy outcome. No effect was observed on pre-implantation loss at any time among any of the groups, but there was a time-dependent and dose-related increase in post-implantation loss. Post-implantation loss was significantly increased after 4 days of treatment and reached nearly 40% after 7 days of drug exposure (10.0 mg/kg). Second, the effect of treatment with single high doses of cyclophosphamide was studied. Male rats were treated with a single dose of cyclophosphamide (10, 30, or 70 mg/kg) and bred 1 day and 4 days post-treatment. No significant change in pre-implantation loss was observed at either time point; no change in post-implantation loss was found after 1 day post-treatment. However, a significant increase in post-implantation loss was observed in the two high-dose groups 4 days post-treatment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Diethyldithiocarbamate (DDC) has been suggested to have both radiosensitizing (due to superoxide dismutase (SOD) inhibition) and radioprotective properties. We have studied the activity of SOD up to 24 h after intratumoral administration of 50, 100, 150, and 300 mg/kg DDC in 3-methylcholanthrene-induced tumors in BALB/c mice. Maximal inhibition of SOD (8% of control) was obtained 1 h after administration of 100 mg/kg DDC. Tumor response to DDC and X irradiation was assessed using a tumor growth-delay assay, after 11 Gy 100-kVp X rays given up to 24 h after DDC administration. Radiation-induced tumor growth delay (7.11 +/- 1.76 days) was enhanced only when tumors were irradiated 2-4 h after 50 mg/kg DDC. When higher doses of DDC were used, tumor cure was noted when DDC was injected 1-6 h before irradiation. We suggest our findings are consistent with radiosensitization being due to SOD inhibition, but that if insufficient time is allowed between DDC injection and irradiation, the sensitization is masked by a radioprotective effect. We believe that further investigations as to the therapeutic potential of DDC in human patients with cancer are warranted.  相似文献   

8.
The effect of pretreatment with carboxymethylglucan (CMG) on the frequency of micronuclei induced by cyclophosphamide administration in mice was evaluated. Two doses of CMG (50 mg/kg body weight) injected either intraperitoneally 24 h or intravenously 1 h prior to two cyclophosphamide administrations (80 mg/kg) significantly decreased the frequency of micronucleated PCE in bone marrow. Of two evaluated derivatives of carboxymethylglucan, the K3 derivative was most efficient. The results show that it is possible to achieve a suppressive effect of soluble carboxymethylglucan prepared from Saccharomyces cerevisiae against cyclophosphamide mutagenicity. The notion may be useful for glucan's effects against pharmacocarcinogenesis. Therapeutic application of glucan with cyclophosphamide therapy may provide a remarkable decrease of the secondary tumour risk. The utilization of these results for human patients needs to be considered.  相似文献   

9.
An ultrastructural and histological study was made to analyse the structural and cellular features of the pulmonary lesions produced in Wistar rats by intraperitoneal (i.p.) administration of cyclophosphamide (two i.p. doses of 150 mg CP/1 kg bw/1 ml PBS). Rats exposed to cyclophosphamide (CP) developed a condition whose morphological picture corresponded to endogenous lipid pneumonia and/or pulmonary alveolar proteinosis-like changes. Damage to the endothelium and neutrophil accumulation in lung vascular bed were found to be potential initiators of endogenous lipid pneumonia-type changes. The possibility of the evolution of the acute lung injury into endogenous lipid pneumonia-type changes and into alveolar proteinosis-like changes was demonstrated. The results of the study supplement the existing theories of pulmonary alveolar proteinosis pathogenesis.  相似文献   

10.
Combined treatment with low doses of X-rays plus cyclophosphamide (0.25 Gy+25 mg/kg body weight) or X-rays plus mitomycin C (0.25 Gy+1.75 mg/kg body weight) did not induce significant dominant lethal effects in any stage of spermatogenesis when a parameter representing pre- and postimplantation loss, such as the decrease of live implants per female, was applied. After combined exposure to high doses of X-rays plus cyclophosphamide (1.00 Gy+100 mg/kg body weight) an increase of dominant lethal mutations (DLMs) was observed in differentiating spermatogonia, spermatids, and spermatozoa with the same parameter. Combined treatment with high doses of X-rays plus mitomycin C (1.00 Gy+5.25 mg/kg body weight) produced DLMs in differentiating spermatogonia and late spermatocytes. A calculation of enhanced risk was applied to the data of DLMs from the combined treatment regimen and was based on the proportion of dead implants (postimplantation loss only). Enhanced risk could be shown not only after high but also after low combined exposure to X-rays plus cyclophosphamide and X-rays plus mitomycin C. With low doses this enhanced risk was observed in spermatids for X-rays plus cyclophosphamide and in differentiating spermatogonia to early spermatocytes for X-rays plus mitomycin C.  相似文献   

11.
The protective effects of carnosine as a natural dipeptide were investigated in mouse bone marrow cells against genotoxicity induced by cyclophosphamide. Mice were injected with solutions of carnosine at three different doses (10, 50 and 100?mg kg(-1) bw) for five consecutive days. On the fifth day of treatment, mice were injected cyclophosphamide and killed after 24?h. The frequency of micronuclei in polychromatic erythrocytes and the ratio of polychromatic erythrocyte/polychromatic erythrocyte?+?normochromatic erythrocyte [PCE/(PCE?+?NCE)] were evaluated by May-Grunwald/Giemsa staining. Histopathology of bone marrow was examined in mice treated with cyclophosphamide and carnosine. Carnosine significantly reduced micronucleated polychromatic erythrocytes (MnPCEs) induced by cyclophosphamide at all three doses. Carnosine at dose of 100?mg kg(-1) bw reduced MnPCEs 3.76-fold and completely normalized the PCE/(PCE?+?NCE) ratio. Administration of carnosine inhibited bone marrow toxicity induced by cyclophosphamide. It appeared that carnosine with protective activity reduced the oxidative stress and genotoxicity induced by cyclophosphamide in bone marrow cells of mice. Copyright ? 2012 John Wiley & Sons, Ltd.  相似文献   

12.
环磷酰胺诱导小鼠血小板减少症模型的建立(英文)   总被引:1,自引:0,他引:1  
比较由环磷酰胺两种不同给药方式诱导小鼠血小板减少症模型的效果,并对效果较稳定的一种给药方式进行最佳造模剂量摸索,以期确定一个造模效果较好,毒副作用较低,利于观察治疗药物疗效的血小板减少症模型。模型A组,第1天尾静脉注射环磷酰胺200 mg/kg,然后连续6 d,每天1次以维持剂量30 mg/kg腹腔注射环磷酰胺。模型B组,按150 mg/kg皮下注射环磷酰胺,每天1次,连续3 d。结果显示模型B组造模效果较好,故以模型B组给药方法进行剂量摸索实验。由第7天的血小板计数可知环磷酰胺低(100 mg/kg)、中(120 mg/kg)、高(140 mg/kg)剂量均可引起血小板减少症,而低剂量组与其他组比较有高效低毒的特点,更有利于观察治疗药物的作用,可用于具有升血小板作用药物的药效学研究  相似文献   

13.
IL-1 has putative chemo- and radioprotective properties, but its effects on primitive hemopoietic stem cell (PHSC) and early multilineage precursor function when given with these modalities is unknown. C57BL6/J (B6) mice, given IL-1 20 h before cyclophosphamide (200 mg/kg for four biweekly doses) or before irradiation (500 cGy), were sacrificed after 4 wk. Their marrow was used as donor cells, and that from B6-Hbb(dGpi1a) (B6-GPI) mice was used as competitor cells in competitive repopulation. Percentages of B6 cells were measured at 30 and 150 days. Stem cell numbers were estimated using binomial statistics. IL-1 alone did not affect stem cell function. As expected, significant declines in early multilineage precursor and PHSC function occurred with chemotherapy and radiation alone. IL-1 with chemotherapy led to exacerbation of these losses in function and numbers (p < 0.05). A similar reduction in function occurred using IL-1 before irradiation. In summary, IL-1 with chemotherapy or radiation worsened chemotherapy- and radiation-induced functional damage to PHSC and other hemopoietic precursors, suggesting that improvements in survival do not necessarily translate into preservation of hemopoietic function.  相似文献   

14.
Fetal rabbits were treated with corticosteroids by maternal administration for 48 h before delivery at 27 days gestational age. Both corticosteroid-treated and control animals then received exogenous natural rabbit surfactant at birth at doses of 0-75 mg lipid/kg. After 10 min of ventilation at tidal volumes of 12-15 ml/kg, static pressure-volume measurements were made. At all surfactant doses there was a significantly higher maximal lung volume, higher dynamic compliance, and lower pressure requirement in the corticosteroid-treated than in the control rabbits (P less than 0.01). Control animals showed incremental improvements in dynamic compliances and maximal lung volumes up to a dose of 50 mg/kg, whereas corticosteroid treated animals improved to a maximum at the low dose of 15 mg/kg (P less than 0.01). However, surface tension as assessed by lung stability index improved with increasing surfactant dose but was not significantly different between corticosteroid-treated and control animals at a given dose. The results imply that maternal corticosteroid treatment potentiates surfactant replacement by a change in lung structure that is independent of surface tension effects.  相似文献   

15.
Cadmium is a well-known human carcinogen. Lipid peroxidation is involved in cadmium-related toxicity and carcinogenesis. Melatonin is an effective antioxidant and free radical scavenger. The potential protective effects of melatonin against cadmium-induced lipid peroxidation in hamster brain, heart, kidney, testes, lung, and liver were examined. Lipid peroxidation was induced by intraperitoneal injection of cadmium chloride [single dose of 1 mg/kg body weight (bw)]. To test whether melatonin would protect against the toxicity of the carcinogen, the melatonin was injected peritoneally at a dose of either 15 mg/kg bw or 5 mg/kg bw, 0.5 h before cadmium treatment and thereafter at 8 h intervals during the day in the 48 h interval following the cadmium injection. One group of hamsters received only a single melatonin injection (a dose of 15 mg/kg bw, 30 min prior to cadmium). Forty-eight hours after cadmium injection, lipid peroxidation increased in brain, heart, kidney, testes, and lung. Either multiple injections of melatonin at both the 5 and 15 mg/kg bw doses, or a single injection of 15 mg/kg bw, prevented the cadmium-related increases in lipid peroxidation in brain, heart and lung. Cadmium-induced lipid peroxidation in kidney was prevented by melatonin when it was given as a single dose of 15 mg/kg bw. Melatonin slightly, but not significantly, reduced cadmium-induced lipid peroxidation in testes. It is concluded that cadmium toxicity, at least with regard to the resulting lipid peroxidation, is reduced by administering melatonin. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

16.
The experiments demonstrated that pretreatment of lethally irradiated recipient (CBA X C57BL/6) F1hybrid mice with cyclophosphamide (200 mg/kg of body weight) on day before the bone marrow transplantation (4 hours after the irradiation) suppressed the allogeneic inhibition of hematopoietic stem cells to 24% (while the inhibition in the untreated animals was 92.5%). It is suggested that cyclophosphamide acted on the recipient's radioresistant lymphoid cells effecting the allogeneic inhibition of stem cells.  相似文献   

17.
T Fujii  T Nakatsuka 《Teratology》1983,28(1):29-33
Teratogenic to subteratogenic doses of x-ray, mitomycin C, MNNG, thio-TEPA, cyclophosphamide, and chlorambucil were administered to pregnant ICR mice together with caffeine at doses of 12.5, 25, or 50 mg/kg on day 11 of gestation. Fetuses were examined for gross malformations on day 18 of gestation. The teratogenicity of mitomycin C was significantly potentiated by caffeine at a dose as low as 12.5 mg/kg. The teratogenicity of chlorambucil was also significantly potentiated by caffeine at 50 mg/kg, but similar potentiation was not observed for x-ray, MNNG, thio-TEPA, and cyclophosphamide.  相似文献   

18.
N, N1-bis (dichloroacetyl) diamine 1, 8-octomethylenediamine (WIN 18,446) is an experimental drug which was first investigated as a male contraceptive. It is soluble in lipid solvents but not in water. The administration of 1,200 to 1,600 mg/kg to pregnant rats on the tenth day of gestation produced multiorgan fetal malformations. Smaller doses, 400 to 800 mg/kg, especially if divided over 2 or 3 days, caused perinatal death. Thus, 60 to 100% of offspring of rats given WIN 18,446 on the tenth and 11th days of gestation died at birth or within 4 days (Taleporos et al., 78). The present study investigated such deaths. At doses of 200 mg/kg on day 10 or 50 mg/kg on days 10 and 11, 67% of offspring had defective or absent diaphragms, 48% had tracheobronchiomegaly with cystic lungs, and 67% had pleural hemorrhage. At doses of 100 mg/kg given on 1 day or 25 mg/kg each day for 2 days, 50% had tracheobronchiomegaly with cystic lungs and rudimentary acini. At lower doses (18.8 mg/kg X 2 or 12.4 mg/kg X 3), a majority of fetal lungs had rudimentary acini, thick septa, few capillaries, and wide cuffs of perivascular connective tissue. Thus, a chemical given during organogenesis produced dysgenesis of the respiratory apparatus. Varying the dose produced malformed lungs with persistently deficient acini which model such human lung faults as tracheobronchiomegaly (Mournier-Kuhn Syndrome; Mounier-Kuhn, '32), bronchiolar dysplasia (Wilson-Mikity Syndrome), and perinatal death with acinar failure resembling neonatal hyaline membrane disease.  相似文献   

19.
Interleukin 1 (IL-1) is a radioprotector of bone marrow and is cytotoxic to some tumor cells. This investigation examines these two properties in the same host animals and gives evidence of radioprotection against localized x-irradiation of the head and neck region. By LD50 analyses, recombinant human IL-1 (100 ng/mouse, approximately 3 micrograms/kg) was found to be radioprotective against whole-body irradiation for both C3H/Km and C57BL/Ka mice. The combined potency ratio for the two strains was 1.07 (95% confidence limit: 1.02-1.12). It was also radioprotective against the injury leading to acute lethality resulting from localized head and neck irradiation of C3H/Km mice; 100 ng of IL-1/mouse produced a potency ratio of 1.05 (95 confidence limit: 1.03-1.07). However, two tumors that originated in C3H/Km mice, RIF-1 and SCCVII, showed neither in vitro nor in vivo response to IL-1. Also, there was no IL-1-induced reduction in in vivo growth of the RL 12NP lymphoma in C57BL/Ka mice.  相似文献   

20.
The effects of anacrotine, a pyrrolizidine alkaloid (PA) which has the structure of senecionine with an additional 6-hydroxy group, have been investigated in weanling male rats. When anacrotine was given i.p. (100 mg/kg), pyrrolic metabolites reached a peak level in the liver during the first 0.5 h, then fell rapidly to a lower level which subsequently declined more slowly. Pyrrolic metabolites accumulated in the lungs during the first hour to a level which then remained relatively steady for at least 4 h. The lung level of pyrrolic metabolites after 2 h was about 39% of the liver level, compared with 16% in rats given senecionine. Anacrotine caused acute centrilobular necrosis and congestion of the liver when 125 mg/kg or more was given i.p., but oral doses (up to 180 mg/kg) caused relatively little liver necrosis. Enlarged hepatocytes developed during ensuing weeks, but these were moderate compared with the bizarre giant cells often associated with pyrrolizidine intoxication. In contrast, anacrotine produced much more severe lung damage than most other pyrrolizidine alkaloids. The lungs were affected by i.p. or oral doses well below those needed to produce acute liver damage. Pulmonary congestion and oedema, extensive necrosis of the pulmonary endothelium, and thickening of alveolar septae, developed within 2 days after dosing. After single i.p. doses of 60 mg/kg or more progressive consolidation of lung tissue often led to death after 2-5 weeks. Hearts showed myocardial necrosis of the right ventricular wall. Dehydroanacrotine, the putative reactive pyrrolic metabolite of anacrotine, given i.v. to rats, caused dose-related chronic lung and heart damage identical to that produced by anacrotine, but after lower doses (6-27 mg/kg); larger amounts caused acute lung damage. It is suggested that the severe lung damage in animals given anacrotine is due to dehydroanacrotine, formed in the liver. This metabolite is more stable than the pyrrolic derivatives of most other pyrrolizidine alkaloids, and it is thus able to reach the lungs in relatively large amounts.  相似文献   

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