首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
EAC4 and EAC14 of high activity were prepared by treating sensitized red cells with human or guinea pig serum in the presence of TTHA, a chelating agent whid at low pH to maximize C1 and C4 activity and to minimize C3 contamination. Cells prepared with guinea pig complement were contaminated with C2, which could be decayed away at 37 degrees C. Cells sensitized with IgG antibody were more reactive than those sensitized with whole serum or with IgM, and preparations made with TTHA-complement were more reactive than those prepared with purified C1 plus EDTA-complement. EAC14 stored at 0 degrees C for 3 weeks lost very little activity.  相似文献   

2.
3.
4.
5.
6.
Therapeutic efficacy of nucleoside analogues (NAs) like Gemcitabine, 5-fluorouracil in cancer treatment is already well established. Most of the known NAs are highly toxic to normal cells due to its non-specific action; thus searching for non-toxic NAs are still going on. For that purpose we have synthesised nine different NAs by alteration of their structural and functional groups. The aim of present study is to investigate the therapeutic potential of NAs against mice bearing breast adenocarcinoma cells at IC50 dose for 10 days treatment schedule. Results of the present study showed that, among the seven nucleoside analogues, NA-7 and NA-9 showed maximum therapeutic efficacy in controlling cancer cells by inhibiting cell proliferation and inducing apoptosis without any adverse effects to normal host cells. Additionally, NAs significantly decreased the tumour burden and enhanced survivability of host through generation of reactive oxygen species in tumour cells. These ultimately led to DNA damage, depolarisation of mitochondrial membrane potential and apoptosis in tumour cells. To find out the molecular mechanisms, we showed that administration of NA-7 and NA-9, down- regulating the expression of Bcl-2, cyclin D1, C-myc, P-21 and up-regulating the expression of P-53, Cyt-c, Bax, caspase-3 and caspase-9. The results suggest that NA-7 and NA-9 exhibits significant antitumor activity than 5-fluorouracil by modulating the cell cycle checkpoints and inducing apoptosis in Ehrlich ascites carcinoma (EAC)-bearing mice. Additionally, NA-7 and NA-9 did not show any clastogenic effect on bone marrow cells at sub-lethal dose. Thus, the present study clearly suggested therapeutic benefit of NAs by augmenting anticancer efficacy and diminishing toxicity to the host.  相似文献   

7.
Inhibitory action of caffeine (a tri-methylxanthine alkaloid) on progression or pathogenesis of lung, breast and ovarian cancer including Ehrlich ascites carcinoma (EAC) cell development has been reported. This information led the authors to study the effect of long-term administration of caffeine (20 mg/kg/day; po for 22-27 consecutive days) on the development of EAC cells in relation to serum gonadal hormones (LH, FSH, 17-OH-beta-estradiol (E2) and progesterone) in adult Swiss albino female mice. Measurement of gonadal hormones in serum using RIA showed that (a) long-term caffeine treatment significantly increased LH (except for 27 consecutive days) and decreased FSH (except for 24 and 27 consecutive days) and both E2 and progesterone (except for 22 and 24 consecutive days) levels, (b) development of EAC cell for 10-15 days, significantly increased LH but decreased FSH, E2 and progesterone levels and (c) long-term caffeine consumption during the development of EAC cell (i) restored the EAC cell- or caffeine-induced induction of LH and reduction of FSH level to their normal levels and (ii) withdrew/reduced the EAC cell-induced reduction in only E2 but not progesterone level. These results therefore, suggest that prolonged caffeine exposures may inhibit the development of EAC cell through the reduction or restoration of EAC cell-induced disruption of ovarian hormonal status to their normal status via the modulation of Hypothalamic-Pituitary-Gonadal (HPG) axis.  相似文献   

8.
目的比较研究不同单位保种的EAC瘤株生物学特性的差异.方法选择研究了北京市肿瘤研究所、山东省医学科学院药物研究所及武汉大学保种中心保存EAC细胞的大小,细胞株体外培养时对血清的依赖性,接种小鼠皮下建立肿瘤动物模型肿块生长曲线,建立的动物模型对环磷酰胺CTX治疗的敏感性等指标.结果发现三个单位保存的EAC细胞形态及大小基本一致;北京EAC体外培养容易生长,7.5%NCS即可生长良好,山东及武汉EAC体外培养生长力较弱;皮下接种BALB/c小鼠后,北京EAC最易生长肿瘤,武汉EAC次之,山东EAC最差;建立的动物模型对CTX治疗的敏感性,依次为北京EAC,武汉EAC,山东EAC,用CTX治疗的抑瘤率相应为82.9%,71.9%,50%.结果可见三个不同单位保种的EAC瘤细胞生物学特性确已存在显著差异.  相似文献   

9.
10.
A relatively rapid chalone assay using inhibition of purified calf thymus DNA polymerase alpha by Ehrlich Ascites Cell (EAC) chalone has been performed. The DNA polymerase alpha was inhibited in a concentration-related fashion by partially purified EAC chalone ranging from 10 to 200 micrograms/ml. Spermidine was also tested since there has been some suggestion that chalone may be spermidine; we found no effect of spermidine at 170 and 230 microM, but marked inhibition at 33 mM. This assay should facilitate chalone purification, since chalone appears to non-specifically inhibit DNA polymerase alpha.  相似文献   

11.
The effect of ferric citrate on active E, EA, and EAC rosette formation by human peripheral blood mononuclear (PBM) cells was examined. Active E and EAC rosette formation was significantly inhibited at four of the five concentrations tested. Inhibition of EAC rosette formation was generally lower than that observed with active E rosette formation. Treatment with Fe3+ had no effect on EA rosette-forming cells.  相似文献   

12.
13.
本文报道了尖吻蝮蛇毒、蝮蛇毒及抗蛇毒血清能使接种S_(180)、EAC腹水癌的小鼠明显延长存活时间、降低接种率,但不能完全阻止痛细胞生长。体外具有较明显的导致,菡细胞肿胀、膜破裂,核纤维化,坏死等。从腹水酶活力测定及抗血清初步研究结果表明,癌细胞病变中产生的某些抗原物质可能与蛇毒中的酶和毒蛋白相近。因此注射蛇毒后可在体内产生相关抗体,中和癌细胞产生的毒素以达到治疗目的。  相似文献   

14.
15.
E (erythrocyte) and EAC (erythrocytes coated with antibody and complement) rosettes were quantitated in baboons, cebus monkeys and cotton-topped marmosets. There was poor correlation between E rosette levels and other parameter of T-lymphocyte function. In nonhuman primates, E rosettes were increased in the presence of thymosin fraction V, while human E rosettes were not affected.  相似文献   

16.
17.
The origin and life span of long-lived small lymphocytes in the bone marrow of mice have been evaluated by the use of radioautography, scintillation counting, and anti-theta serum. Thymus-deprived BALB/C mice and nude mice had a smaller percentage of long-lived lymphocytes in bone marrow and in thoracic duct lymph than sham-operated or normal littermates. Furthermore, the long-lived lymphocytes in the marrow of nudes have more varied—but generally shorter—life spans than long-lived lymphocytes from mice having a thymus. In thoracic duct lymph of nude mice a more homogeneous long-lived population—according to life span—was found.It was concluded that both long-lived T cells and long-lived B cells are normal residents in the bone marrow. Furthermore, it was concluded that cells of variable life spans comprise the B lymphocyte population: short-lived cells with life spans of 3–5 days and long-lived lymphocytes with life spans of weeks to months.  相似文献   

18.
19.
The proportion of lymphocytes forming E, EA, and EAC rosettes after treatment with human interferon preparations in vitro was measured. While interferon increased the percentage of lymphocytes forming E rosettes, the percentage of cells forming EA rosettes was diminished. The proportion of lymphocytes forming EAC rosettes was not altered to any major extent by interferon treatment. The same effects were observed when fibroblast interferon, purified to homogeneity with regard to molecular weight, was used.  相似文献   

20.
Serum from C3H/HeJ mice in contrast to serum from other mouse strains does not convert EA into EAC. A factor in supportive serum permits nonsupportive C3H/HeJ serum to produce a functional EAC-rosetting reagent. This factor is heat stable. Its concentration in serum parallels the sensitivity of mice to LPS. It is absent or inoperative when sensitivity is reduced on a genetic basis and increased when sensitivity is increased by treatment with BCG.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号