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1.
N. Torlone A. Piazza M. Valeri P. I. Monaco L. Provenzani E. Poggi D. Adorno C. U. Casciani 《Transplant international》1992,5(Z1):S676-S678
Donor-specific anti-HLA antibodies were studied by cytotoxicity crossmatching (CTXM) and flow cytometry crossmatching (FCXM) in 117 kidney transplant candidates; the same study was carried out in 33 cadaver-donor kidney recipients, during the first 3 post-transplant months, for which donor cells were available. Pre-transport evaluation showed that 82.9 % of subjects were CTXM negative/FCXM negative, 6.8 % of patients were positive in both tests, and 10.3 % were CTXM negative/FCCM positive. Post-transplant monitoring for donor-specific antibodies (Abs-DS) showed that nine recipients (27.3 %) were FCXM positive; six of them were IgG + and three IgM +. In comparing these results with the clinical course, a significant association between FCXM IgG + and rejection episodes was observed (P < 0.01). 相似文献
2.
Meghna R Adhvaryu Narshimha Reddy Minoo H Parabia 《African journal of traditional, complementary, and alternative medicines》2008,5(4):409-418
The anti-tumor activity and chemopreventive potential of four Ayurvedic herbs viz. Curcuma longa L., Ocimum sanctum L., Tinospora cordifolia (Wild) Miers ex Hook.f & Thomas and Zizyphus mauritiana Lam. were evaluated using Dalton Lymphoma ascites (DLA) tumor model in Swiss Albino mice. The outcome was assessed using survival time, peritoneal ascitic fluid (Tumor volume) and hematological indices as parameters. Animals were divided into five groups (n = 6) viz. one DLA control and four Herb + DLA treated groups. All the four herb + DLA groups were pre-treated with respective herbs for 7 days and hematological indices were measured for entire five groups. On day-8 animals were inoculated with 1×106 DLA cells i.p., and Herb + DLA groups were continued with oral herbal treatment for 21-days. Hematological parameters and tumor volume were assessed to find the effects of herbs. Short term in vitro cytotoxicity was determined by Trypan Blue exclusion method and LDH leakage assay using different concentrations of herbal extracts and 5-FU as a positive control and IC50 for each herbal extract and 5-FU were determined. Oral administration of crude herb increased the survival time and decreased the peritoneal ascitic fluid content significantly. Hb, RBCs and total WBC which were altered by DLA inoculation were restored significantly by all the herbs except O. sanctum. All the four herbs showed in vitro cytotoxic activity against DLA cell-line. Moreover inter group comparison of all the four herbs for anti-tumor activity showed efficacy in the following order- T. cordifolia > Z. mauritiana ≥ C. longa > O. sanctum respectively. 相似文献
3.
When liriodendrin or syringin was incubated for 24 h with human intestinal bacteria, two metabolites, (+)-syringaresinol-beta-D-glucopyranoside and (+)-syringaresinol, from liriodendrin and one metabolite, synapyl alcohol, from syringin were produced. The metabolic time course of liriodendrin was as follows: at early time, liriodendrin was converted to (+)-syringaresinol-beta-D-glucopyranoside, and then (+)-syringaresinol. The in vitro cytotoxicities of these metabolites, (+)-syringaresinol and synapyl alcohol, were superior to those of liriodendrin and syringin. 相似文献
4.
Cytotoxicity of urushiols isolated from sap of Korean lacquer tree (Rhus vernicifera stokes) 总被引:1,自引:0,他引:1
Hong DH Han SB Lee CW Park SH Jeon YJ Kim MJ Kwak SS Kim HM 《Archives of pharmacal research》1999,22(6):638-641
Cytotoxicities of four urushiols, congeners isolated from the sap of Korean lacquer tree (Rhus vernicifera Stokes), to 29 human cancer cell lines originated from 9 organs were evaluated. Their values of 50% growth inhibition were below 4 microg/ml, and showed cell line specific cytotoxicity. The present result is the first report on the cytotoxicity of urushiols suggesting that they would have an anticancer activity to human cancer cells. 相似文献
5.
背景与目的:脑胶质瘤是常见的颅内肿瘤,占脑恶性肿瘤的50%以上,化疗作为综合治疗的一项重要手段,仍存在效果不理想、易耐药等问题。本文就研究中华眼镜蛇毒组分C(Fraction C from Naja Naja Actra Venom,NNAV.FC)体外对人胶质瘤细胞株U-251的细胞毒性作用,并与几种临床脑肿瘤化疗用药进行比较,以求为脑胶质瘤的治疗提供新的化疗药物。方法:应用MTT法.观察NNAV.FC人胶质细胞瘤株U-251的细胞毒作用、量效关系等,并与依托泊苷(vp=16、鬼臼乙叉苷、Vepesid)、卫萌(替尼泊苷、鬼臼甲叉甙vm-26,Teniposide)、顺铂(Cisplatin、CDDP)、卡铂(Carboplatin)、五氟尿嘧啶(5-FU)等对上述细胞的细胞毒作用进行比较。结果:FC对人胶质瘤细胞有明显的抑制作用,其24及48h的IC50分别为5.76和7.19μg/ml,且呈良好的量效关系。结论:在本实验中,FC能有效抑制胶质瘤细胞株的生长,抑制作用与浓度呈正相关,与临床胶质瘤化疗药相比较。FC是有效地抑制胶质瘤细胞生长的药物。 相似文献
6.
观察EGF-PE40重组毒素对喉鳞癌细胞的毒性作用,为寻找新型的治疗头颈鳞癌的生物制剂奠定基础。应用MTT比色法测定EGF-PE40重组毒素的生物学活性。并在光镜下观察Hep-2细胞形态变化。确定MTT比色法中Hep-2细胞浓度为2×104/well。选择10%SDS-0.01mol/LHCI作为MTT结晶的溶解液,当EGF-PE40重组毒素为0.53ng/ml时,50%的Hep-2细胞死亡,在一定范围内,随重组毒素增加,细胞损伤加重。 相似文献
7.
新天然来源抗生素-抗霉素A_(18)的抗肿瘤活性及其产生菌I07A-01824的生物学特征 总被引:1,自引:0,他引:1
目的检测抗霉素A18的体外抗肿瘤活性并对其产生菌I07A-01824的形态及培养特征,生理生化特征等进行研究。方法用MTT法检测抗霉素A18的肿瘤细胞生长抑制作用,用流式细胞术测定其对细胞周期的影响;按分类学常规方法研究菌株I07A-01824的形态及部分生理生化特征。结果抗霉素A18能够抑制人肝癌细胞HepG2、人口腔上皮癌细胞KB的生长;这两个细胞株均被阻滞在细胞周期的S期。菌株I07A-01824的形态及培养特征与已知种——黄白链霉菌(Streptomyces albidoflavus)一致。结论红树林内生放线菌是新抗生素的重要来源。 相似文献
8.
目的:探讨野桃树根对肝癌细胞毒作用。方法:肝癌细胞株与野桃树根浸出液共同体外培养,MTT法测细胞毒作用。结果:0.2%,0.1%,0.05%,0.025%浓度的野桃树根浸出液对SMMC7721细胞的抑制率分别为77.97%,64.06%,36.34%,33.75%;0.2%,0.1%,0.05%,0.025%,0.0125%浓度的野桃树根浸出液对SK-HEP-1细胞的抑制率分别为100%,100%,100%,88.98%,82.64%。结论:野桃树根浸出液在体外对肝癌细胞有较强的杀伤作用。 相似文献
9.
目的比较抗菌肽Maximin衍生物(M1~M19)的体外杀精效果和细胞毒性作用,筛选有进一步研究价值的候选体外杀精剂。方法利用Sander-Cramer方法评价抗菌肽的体外杀精效果;CCK-8试剂盒测定抗菌肽对Hela-229的细胞毒性,筛选出具有较强杀精作用和低细胞毒性的抗菌肽。结果 19种抗菌肽衍生物中,M1、M7、M11、M15和M17五种抗菌肽在2 000mg/L时均能完全制动精子,其中100%制动精子的最低浓度EC100分别是:M7=M11=2 000mg/L,M1=M15=M17=1 500mg/L;利用Hela-229细胞分析细胞毒性时,M11的细胞毒性明显低于其他4种抗菌肽,表现出较高的安全性。结论对19种抗菌肽衍生物的体外研究表明,抗菌肽M11具有较强的杀精作用,且细胞毒性低,有望成为体外杀精剂的候选药物。 相似文献
10.
Franco Dallegri Guido Frumento Alberto Ballestrero Loris Banchi Franco Patrone 《Annals of hematology》1985,51(2):97-102
Summary Neutrophil-derived nucleus- and granule-free cytoplasts, consisting of cytosol enclosed by an intact plasma membrane, were able to destroy 51Cr-labelled ox red blood cells (ORBC) in the presence of phorbol myristate acetate (PMA). The slope of the target cell lysis vs the log of the cytoplast number was similar to that observed with neutrophils as effector cells. Nevertheless, a number of cytoplasts 60–80 times higher than that of neutrophils was required to obtain a common level of cytotoxicity. The ability of cytoplasts and neutrophils to lyse ORBC was completely abolished by catalase and unaffected by superoxide dismutase and mannitol, suggesting the involvement of hydrogen peroxide in the target cell damage. Addition of myeloperoxidase (MPO) to cytoplasts increased lysis. The MPO inhibitor azide significantly reduced the cytolysis by neutrophils, but not the cytolysis by cytoplasts, except when experiments were carried out in the presence of MPO. The results indicate that neutrophil cytosol and plasma membrane represent the basic requirement for the PMA-dependent cytolytic process, whereas MPO behaves as a device to amplify lysis. 相似文献