The in vitro biological activity of selected South African Commiphora species

Ten South African Commiphora (Burseraceae) species were investigated to validate their use in traditional healing rites. The leaf and stem extracts of each species were analysed for the anti-oxidant (ABTS and DPPH assays), antimicrobial (MIC and death kinetic assays), anti-inflammatory (5-LOX assay), anticancer (SRB assay) properties, as well as the cytotoxic effects (tetrazolium-based assay). The best anti-oxidant activity (ABTS assay) was observed for the stem extracts of Commiphora tenuipetiolata IC(50)=5.10 microg/ml), Commiphora neglecta (IC(50)=7.28 microg/ml) and Commiphora mollis (IC(50)=8.82 microg/ml). Extracts generally exhibited poor anti-oxidant activity in the DPPH assay, with the exception of Commiphora schimperi (stem), Commiphora neglecta (stem), Commiphora tenuipetiolata (stem and leaf), and Commiphora edulis (stem), with IC(50) values ranging between 7.31 and 10.81 microg/ml. The stem extracts exhibited moderate to good 5-LOX inhibitory activity with Commiphora pyracanthoides (stem) displaying the greatest inhibitory effect (IC(50)=27.86+/-4.45 microg/ml). For the antimicrobial (MIC) assay, a greater selectivity was exhibited by the extracts against the Gram-positive bacteria (0.01-8.00 mg/ml) and the yeasts (0.25-8.00 mg/ml) than against the Gram-negative bacteria (1.00-8.00 mg/ml). Using death kinetic studies (time-kill studies), the rate at which Commiphora marlothii (stem) kills Staphylococcus aureus over a 24h period was determined. Mostly, a concentration-dependent antibacterial activity was observed beginning after ca. 30 min. All concentrations exhibited antibacterial activity, with complete bactericidal effect achieved by the 24(th) hour. The most active Commiphora species against the HT-29 cells (SRB anticancer assay) were Commiphora glandulosa (leaf and stem) and Commiphora marlothii (leaf). The MCF-7 cells (SRB anticancer assay) exhibited the highest sensitivity to indigenous Commiphora species, with Commiphora edulis (leaf and stem), Commiphora glandulosa (leaf and stem), Commiphora marlothii (leaf), Commiphora pyracanthoides (leaf and stem), Commiphora schimperi (stem), and Commiphora viminea (stem) all possessing a percentage inhibition greater than 80% at 100 microg/ml. Commiphora glandulosa (leaf and stem) and Commiphora pyracanthoides (leaf and stem) were the two most active species against the SF-268 cells (SRB anticancer assay), with IC(50) values ranging between 68.55+/-2.01 and 71.45+/-1.24 microg/ml. The majority of the Commiphora extracts were largely non-cytotoxic against Graham human kidney epithelial cells when investigated in the MTT assay.     

奥沙利铂与羟基喜树碱单用及联合应用对人大肠癌疗效的研究

目的观察奥沙利铂(L-OHP)、羟基喜树碱(HCPT),顺铂(CDDP),5-氟尿嘧啶(5-Fu),丝裂霉素(MMC)及表阿霉素(EPI)在体外单用及两药联用时对人大肠癌标本的敏感性。方法MTT法检测药敏结果,按中效原理计算不同药物联用的效果。结果大肠癌敏感率由高至低的单药依次为L-OHP>HCPT>CDDP>5-FU>MMC>EPI。联合用药组依次为L-OHP HCPT、L-OHP 5-Fu、HCPT MMC、HCPT CDDP、HCPT 5-Fu与MMC 5-Fu。L-OHP与HCPT对大肠癌敏感性均好。尤其是低分化癌。EPI对大肠癌细胞不敏感。L-OHP HCPT联合用药都对大肠癌最敏感。结论L—OHP与HCPT单用及联合用药对大肠癌细胞最敏感,尤其对低分化的癌的效果优于CDDP、MMC与5-Fu单药及联用。     

MTT法用于抗癌药物筛选的实验研究

本文就MTT法在抗癌药物筛选试验中的应用方面进行了初步探讨,结果显示该方法简便、快速.细胞浓度以1—5×10~4/孔较为适宜,吸光度30min内不变.DMSO为MTT法的想理溶剂,但需除去蛋白质的影响.MTT以5mg/ml与细胞反应4h为佳.批内CV值为10%左右.四种抗癌药物对瘤株细胞SW-480作用后,其敏感程度各异     

苏拉明对体外培养视网膜色素上皮细胞增殖的影响

目的　研究苏拉明 (suramin)对培养人视网膜色素上皮细胞 (retinal pigm ent epithelium,RPE)增殖的影响 .方法　将不同质量浓度的苏拉明 (1.5 ,15和 15 0 mg· L- 1 )加入RPE细胞培养液 ,采用四甲基偶氮唑盐 (tetrazolium,MTT)比色法 ,细胞分裂指数计数和核仁组成区嗜银染色(Ag NORs)检测苏拉明对 RPE增殖活力的影响 .结果　含有10 0 m L· L- 1小牛血清的培养液可以显著刺激 RPE的增殖(P<0 .0 1) ,无血清组 A值为 0 .19± 0 .0 1、含血清组 A值为0 .30± 0 .0 1;苏拉明抑制了 10 0 m L· L- 1血清条件下 RPE的增殖 ,呈剂量依赖性 ,最大抑制率达 5 1% ,3种浓度组 A值分别为 0 .2 9± 0 .0 1,0 .2 4± 0 .0 1和 0 .14± 0 .0 1,对细胞的形态无明显影响 .结论　苏拉明对血清刺激 RPE增殖有显著非毒性抑制作用     

康莱特联合5-Fu对肝癌细胞Heap1-6的作用

目的研究康莱特（KLT）联用半量最佳体外抑瘤浓度5-氟尿嘧啶（5-Fu）、单药全量5-Fu对体外小鼠Heap1-6肝癌细胞增殖及凋亡的影响。方法采用MTT法检测各药物组对细胞活性的影响;采用流式细胞术分析各药物组对肝癌细胞株Hepa1-6细胞周期的影响。结果 MTT示：康莱特联用半量5-Fu较单药全量5-Fu的抗肿瘤效果显著;高剂量康莱特联合半量5-Fu的抗肝癌效果较低、中剂量组联合组显著。流式细胞术示：不同浓度的康莱特联合半量5-Fu较全量5-Fu的促凋亡作用差异在中剂量时差异无显著性。结论中剂量的康莱特联用半量5-Fu对肿瘤细胞的抑制作用及促凋亡作用与单药5-Fu的疗效相当,可以指导临床用药。     

穿心莲内酯对不同分化胃癌细胞株的体外增殖的影响

[目的]明确穿心莲内酯对不同分化胃癌细胞株的体外增殖的影响.[方法]以不同浓度的穿心莲内酯处理低分化(MKN45)、中分化(SGC7901)和高分化(MKN28)胃腺癌细胞株,分别温育24h、48h,72h;采用噻唑蓝比色法检测各和穿心莲内酯对癌细胞的药物半数抑制浓度(IC50),比较穿心莲内酯对不同分化胃癌细胞株的体外增殖抑制作用的异同.[结果]穿心莲内酯对胃癌细胞株MKN45、SGC7901、MKN28的体外增殖均具有显著的抑制作用,并且呈剂量效应和时间效应关系.低分化的MKN45细胞株对穿心莲内酯的敏感性明显高于高分化的MKN28细胞株和中分化的SGC7901细胞株.[结论]穿心莲内酯对不同分化程度的胃腺癌细胞株体外增殖抑制作用不同.     

庆大霉素对体外培养的肾小管上皮细胞损伤作用的研究

目的探索庆大霉素(GM)对体外培养的肾小管上皮细胞的损伤情况。方法采用MTT比色法和3H-TdR掺入法,观察庆大霉素对体外培养的肾小管上皮细胞增殖的影响。结果一定浓度下(0·4mmol·L-1)的庆大霉素能够使体外培养的肾小管上皮细胞MTT值下降(P<0·05),而3H-TdR掺入率升高(P<0·05);当庆大霉素浓度为1·0mmol·L-1时,能够使体外培养的肾小管上皮细胞MTT值下降(P<0·05),3H-TdR掺入率也下降(P<0·05)。结论一定浓度下(0·4mmol·L-1)的庆大霉素对体外培养的肾小管上皮细胞就有损伤作用,只有当GM浓度达到1·0mmol·L-1时3H-TdR掺入率才有减少,肾小管上皮细胞的增殖作用才会减少。     

Gallic Acid-Functionalized,TiO2-Based Nanomaterial—Preparation,Physicochemical and Biological Properties

Wound healing and skin tissue regeneration remain the most critical challenges faced by medical professionals. Titanium(IV) oxide-based materials were proposed as components of pharmaceutical formulations for the treatment of difficult-to-heal wounds and unsightly scarring. A gallic acid-functionalized TiO₂ nanomaterial (TiO₂-GA) was obtained using the self-assembly technique and characterized using the following methods: scanning electron microscopy (SEM), transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), X-ray powder diffraction (XRPD), infrared spectroscopy (IR), Raman spectroscopy and thermogravimetry (TG). Additionally, physicochemical and biological tests (DPPH assay, Microtox^® acute toxicity test, MTT assay) were performed to assess antioxidant properties as well as to determine the cytotoxicity of the novel material against eukaryotic (MRC-5 pd19 fibroblasts) and prokaryotic (Staphylococcus aureus, Escherichia coli, Candida albicans, Aliivibrio fischeri) cells. To determine the photocytotoxicity of the material, specific tests were carried out with and without exposure to visible light lamps (425 nm). Following the results, the TiO₂-GA material could be considered an additive to dressings and rinsing suspensions for the treatment of difficult-to-heal wounds that are at risk of bacterial infections.     

反油酸对人脐静脉平滑肌细胞活力的影响

<正>平滑肌细胞是血管壁中膜的主要细胞成分,是动脉粥样硬化(atherosclerosis,As)和血管成形术后再狭窄(restenosis after angioplasty,RAA)等病理过程形成和发展的重要部位,对血管壁的完整性和紧张性的调节也起重要作用,其异常增殖及形态学转变将导致动脉粥样硬化过程     

繁枝蜈蚣藻粗提物体外抗单纯疱疹病毒研究

目的：研究海藻繁枝蜈蚣藻抗单纯疱疹病毒Ⅰ型活性。方法：采用空斑减数实验测定5种不同提取方法所得蜈蚣藻粗提物抗HSV-1活性，计算空斑抑制率：郁ED50，并从药物对细胞的保护、对病毒增殖的影响及对病毒感染细胞的综合作用3个方面初探繁枝蜈蚣藻抗单纯疱疹病毒活性机理。结果：蜈蚣藻多糖能明显抑制HSV-1的致病变作用，ED。依次为8．72、12，16、8．93、8．49和805982．62μg／ml，药物住对细胞的保护及对病毒感染细胞的综合作用中均表现出明显活性。结论：繁枝蜈蚣藻有显著的抗HSV-1活性，且初步推测蜈蚣藻多糖抗HSV-1活性是作用在病毒和受体结合、侵入Vero细胞阶段。