低锌浓度培养基对Caco2细胞二价金属离子转运体mRNA表达的影响

锌是人体必需的微量营养素之一，锌缺乏或过量与多种机能紊乱相关。二价金属离子转运体（divalent metaltransporter 1，DMT1）是近期发现的哺乳动物金属离子转运体，在机体所有组织几乎均有表达，具有对铁、锌等多种二价金属离子的转运功能。我们既往的实验结果显示膳食高锌可以导致断乳小鼠睾丸DMT1 mRNA表达显著降低，约为适锌时表达量的1／3～1／4，提示可能为哺乳期后幼鼠维持锌内稳态的一种反馈保护机制，但是脑组织中的DMT1 mRNA表达未见变化，提示在脑组织锌转运中DMT1可能不作为主要的转运体。小肠是锌吸收的重要场所，DMT1是否参与小肠锌吸收过程？我们以不同锌浓度培养的Caco2细胞为模型，观察其对DMT1 mRNA表达的影响及其规律，探讨DMT1在小肠锌吸收中的可能作用。     

不同锌浓度培养液细胞存活率的测定

为了对锌的细胞毒性提供实验参考 ,利用MTT比色法测定 4种不同锌浓度下HEK 2 93细胞的存活率 ,发现随着培养液锌浓度的增高 ,细胞存活率下降 ,尤其是培养液锌浓度大于 10 0 μmol/L时下降显著。     

高浓度锌对Caco-2细胞生长的影响

本实验利用MTT比色法测定不同锌浓度处理下Caco-2细胞生长状况,并通过对细胞存活率比较,分析该细胞株对高锌的耐受程度。     

MTT法检测医用高分子材料浸出细胞毒性的实验研究

介绍了在微量细胞培养板中，用四甲基偶氮唑盐（ＭＴＴ）比色法检测医用高分子材料浸出细胞毒性的方法。研究了不同细胞接种浓度下，ＭＴＴ比色法的重现性，并且在同一细胞浓度下，将此方法和细胞计数法进行了比较。结果表明，此方法操作简便，结果稳定，重复性好．     

避孕套的体外细胞毒性检测实验

目的:通过两种避孕套的体外细胞毒性实验,探讨适合避孕套的细胞毒性检测方法。方法:按照GB/T16886.5的体外细胞毒性评价方法要求,用琼脂覆盖法和MTT比色法检测两种避孕套的细胞毒性。结果:用琼脂覆盖法检测出两种避孕套的细胞毒性均为2级;用MTT比色法检测时,在浸提液浓度为50%时,相对增值率(RGR)避孕套A为5%,避孕套B为7%,两者差异无统计学意义(P>0.05);在浸提液浓度为10%时,避孕套A的RGR为87%,避孕套B为99%,两者差异无统计学意义(P>0.05);在浸提液浓度为20%时,避孕套A的RGR为42%,避孕套B为77%,两者有统计学差异(P<0.05)。结论:由于MTT比色法具有定量评价的优点,更适合避孕套的细胞毒性检测。     

不同浸提介质对医用护理垫体外细胞毒性评价的影响简

目的：研究不同浸提介质对医用护理垫体外细胞毒性评价的影响。方法：根据ISO 10993-5：2009的试验原则和评价标准,采用不同的浸提介质制备医用护理垫浸提液,小鼠成纤维细胞L929与浸提液共培养24h,MTT 法评价浸提液对细胞生长的影响,并计算细胞存活率（Viab.%）。结果：医用护理垫不同浸提液的细胞毒性结果有统计学差异,含血清浸提介质使细胞生长抑制,Viab.%值为68.6%,而其余三种浸提介质细胞生长状态良好, Viab.%均＞80%。结论：不同的浸提介质对医用护理垫细胞毒性结果有直接影响,因此在评价医用材料的细胞毒性时,必须明确所使用的浸提介质。     

NDRG2在乳腺癌细胞系中的表达及其对乳腺癌细胞生长的影响

目的：检测NDRG2在各种乳腺癌细胞系中的表达,并观察高表达NDRG2对乳腺癌细胞生长的影响。方法：应用PCR技术及Western blot法检测NDRG2的表达水平,转染pcDNA3.1-NRDG2质粒,绘制生长曲线,观察细胞的生长情况。结果：MDA-MB-453和MDA-MB-231细胞中NDRG2的表达较低;pcDNA3.1-NRDG2能够在MDA-MB-453中成功高表达NRDG2;高表达NRDG2的MDA-MB-453细胞生长速度明显降低。结论：NRDG2能够抑制乳腺癌细胞MDA-MB-453的生长。     

三氧化二砷对肝癌HepG2细胞铁死亡影响的研究

目的 探究三氧化二砷是否会诱导肝癌细胞铁死亡,并比较Alamar blue 法和MTT法在肝癌细胞铁死亡中检测细胞活力的差异。方法 以人肝癌HepG2细胞为研究对象,分为对照组、三氧化二砷处理组、公认的铁死亡诱导剂Erastin处理组以及联合铁死亡抑制剂Ferrostatin-1处理组,分别采用倒置生物显微镜观察各组细胞形态及存活情况,采用MTT法和Alamar blue 法检测各组细胞活力,探索三氧化二砷是否可以诱导铁死亡。结果 不同浓度三氧化二砷或Erastin处理后,HepG2细胞出现不同程度的死亡;铁死亡抑制剂Ferrostatin-1可以抑制Erastin诱导的细胞铁死亡,但不能抑制三氧化二砷诱导的细胞死亡;与MTT法相比,Alamar blue 法在检测细胞铁死亡时与显微镜观察结果一致,且各浓度组内检测值标准差较小。结论 三氧化二砷可能不会诱导肝癌细胞铁死亡;Alamar blue 法较MTT法在肝癌HepG2细胞铁死亡后活力检测中有更高的灵敏性,是细胞铁死亡研究中活力检测的首选方法。     

锌对Caco2细胞ZIP4 mRNA表达的影响

目的研究锌对Caco2细胞ZIP4mRNA表达的影响及其规律。方法通过锌特异螯合剂TPEN建立低锌Caco2细胞模型,RT-PCR法获得ZIP4cDNA片断,10μmol/LTPEN培养基诱导后,分别检测0、2、4、6、8和10h时点ZIP4mRNA的表达,及0、2·5、5、7·5、10μmol/LTPEN培养基诱导6h,检测各浓度组ZIP4mRNA的表达。结果RT-PCR获得单一条带的片断,大小与设计一致,获得正确的ZIP4cDNA片断,随着低锌时间的增加,ZIP4mRNA表达也升高,6h达到峰值;随着TPEN浓度的升高,ZIP4mRNA表达也随之升高。结论ZIP4mRNA表达受锌的调控,提示可能参与小肠对锌的吸收。     

MTT法和LDH法评价纳米银抗菌凝胶的体外细胞毒性

目的：对纳米银抗菌凝胶进行体外细胞毒性评价。方法：试验选用L929小鼠成纤维细胞,通过MTT试验和LDH试验,对被测物进行研究。结果：MTT试验的LC₅₀为0.047g/mL,LDH试验的LC₅₀为0.048g/mL。结论：纳米银离子会破坏细胞线粒体和细胞膜完整性。     

体外消化/Caco-2细胞方法评价富铁小麦生物利用率

目的通过研究生物强化富铁小麦面粉的铁生物利用率,筛选出最具潜力的富铁小麦品种。方法采用体外消化/Caco-2方法对10种生物强化富铁面粉进行铁生物利用率比较,以人Caco-2细胞铁蛋白生成量来反映铁生物利用率。结果发现不同面粉间铁生物利用率差异有显著性,出粉率78%的安阳中优9507和京冬8号面粉的铁生物利用率最高。结论生物强化富铁小麦安阳中优9507和京冬8号是最具潜力品种。     

Chicken thigh, chicken liver, and iron-fortified wheat flour increase iron uptake in an in vitro digestion/Caco-2 cell model

The objective of this study was to test meat and fortified-food combinations to identify those that optimize iron uptake in an in vitro digestion/Caco-2 cell model, a proxy for iron bioavailability. Four experiments tested combinations of meats such as chicken (blood, spleen, liver, thigh), beef (cube steak), and fish (whole-fish meal) with iron-fortified foods (rice cereal, maize-soy flour, wheat flour). Chicken liver, thigh, spleen, blood, or fish meal increased the Caco-2 cell iron uptake from these combined with rice cereal (P < .05). Chicken liver, thigh, blood, and beef increased the Caco-2 cell iron uptake from these combined with wheat flour (P < .05). Chicken liver and thigh were tested further. Compared with the liver or thigh alone, adding fortified foods to these meats did not increase the Caco-2 cell iron uptake (P ≥ .05). Adding either meat to the 3 fortified foods increased the Caco-2 cell iron uptake of the fortified foods (P < .05). Chicken liver, chicken thigh, and wheat flour were selected for an infant porridge because the combinations with the highest Caco-2 cell iron uptake were chicken thigh + wheat flour, chicken liver + wheat flour, and chicken liver + maize-soy flour, and wheat flour was the least expensive fortified food sold in the target population. Per unit of iron, the chicken thigh + wheat flour and chicken liver + wheat flour combinations resulted in the highest bioavailable iron. In the proportion of 3:1 fortified food:meat examined, meat increases the bioavailability of iron-fortified foods, but iron-fortified foods do not enhance total iron bioavailability when added to meat.     

The effect of plant sterol-enriched turkey meat on cholesterol bio-accessibility during in vitro digestion and Caco-2 cell uptake

This study evaluated the effect of a plant sterol-enriched turkey product on cholesterol bio-accessibility during in vitro digestion and cholesterol uptake by Caco-2 monolayers. Turkey products, one plant sterol-enriched (PS) and one plant sterol-free (C), were produced in an industrial pilot plant. Before simulated digestion, matrices were spiked with cholesterol (1:5 weight ratio of cholesterol to plant sterol). Plant sterols were included at a concentration equivalent to the minimum daily intake recommended by the European Food Safety Authority (EFSA) for cholesterol lowering. After simulated digestion, the percentage of cholesterol micellarization and uptake by Caco-2 cells in the presence of PS meat were measured. Compared to C meat, PS meat significantly inhibited cholesterol micellarization on average by 24% and Caco-2 cell accumulation by 10%. This study suggests that plant sterols in meat can reduce cholesterol uptake by intestinal epithelia and it encourages efforts to make new PS-based functional foods.     

选择性COX-2抑制剂对大肠癌细胞生长的影响

目的　观察塞来昔布对大肠癌细胞株HT -2 9细胞增殖和凋亡的影响 ,为治疗结肠癌寻找安全有效的化疗药物。方法　采用噻唑蓝 (MTT)比色法 ,流式细胞仪 (FCM)、吖啶橙 /溴化乙啶染色结合荧光显微镜等技术 ,研究塞来昔布对HT -2 9细胞增殖和凋亡的影响。结果　MTT比色法显示体外塞来昔布抑制HT -2 9细胞生长 ,呈浓度和时间依赖性。FCM结果显示典型的亚二倍体“凋亡峰” ,凋亡率在 ( 7 3 1± 2 3 7) %～ ( 4 8 3± 2 86) %;使G0 /G1 期细胞比例升高 ,S期和G2 /M期比例下降 ,呈一定剂量依赖关系。荧光显微镜下见典型的凋亡形态学改变 :细胞体积缩小、细胞核固缩、凋亡小体形成等。凋亡比例呈剂量和时间依赖。结论　体外塞来昔布抑制HT -2 9细胞增殖 ,并诱导细胞凋亡。这种作用可能与阻止细胞周期进展有关     

番茄红素对人前列腺癌细胞生长的影响

目的：观察番茄红素对体外培养的人前列腺癌DU－145和LNCaP细胞存活率、细胞周期和凋亡的影响。方法：用MTT检测番茄红素对DU－145和LNCaP细胞作用的时间效应和剂量效应;流式细胞仪观察番茄红素处理人前列腺癌细胞后细胞周期以及细胞凋亡的改变。结果：番茄红素对DU－145细胞的增殖有明显抑制作用,抑制率可达78％,并有剂量-效应关系。流式细胞仪分析显示,番茄红素可影响该细胞周期并引起细胞凋亡,凋亡率最高达42．42％。而对LNCaP细胞作用不明显。结论：番茄红素对人前列腺癌细胞DU－145具有直接抑制作用,其抑制机理是通过影响人前列腺癌细胞的生长周期和诱导其凋亡而实现。本研究同时也显示番茄红对激素不依赖型细胞DU－145作用较激素依赖型细胞LNCaP敏感。     

EDTA-K_2浓度对全血细胞分析的影响

目的观察不同浓度的抗凝剂EDTA-K2对血细胞分析仪检测参数的影响。方法分别取EDTA-K2不同抗凝比例的新鲜静脉血进行血细胞检测,并与正常浓度组对照作对比分析。结果高浓度抗凝剂引起RBC、PLT计数结果降低,WBC增高且分类不符。低浓度抗凝剂引起RBC、PLT偏低,WBC偏高。结论合适的抗凝比例是保证血细胞分析准确性的前提保障。     

锰的离子价态对大鼠心肌线粒体膜电位的影响

[目的]通过实验观察染锰后大鼠心肌线粒体膜电位(ΔΨM)的变化,探讨不同价态锰在不同剂量时,对心肌线粒体的毒作用及其强度。[方法]Wistar4月龄大鼠,断头处死,提取心肌线粒体,分别用Mn2+和Mn3+(终浓度为50、100、200、400μmol/L)染毒10min后,加入含罗丹明(Rhodamin123)的反应缓冲液中,用单波长荧光分光光度计测定在激发波长503nm、发射波长527nm条件下,3min内样品罗丹明荧光值的改变,代表ΔΨM的变化。[结果]Mn2+各染毒剂量组与对照组比较,ΔΨM下降,且差异有显著性(P<0.05);各染毒剂量组之间ΔΨM差异无显著性。Mn3+各染毒剂量组ΔΨM明显低于对照组,且差异有显著性(P<0.05)。各染锰组ΔΨM随浓度的增加而降低,组间相比差异有显著性(P<0.05)。经回归分析Mn3+、Mn2+对ΔΨM影响的b值95%可信区间分别为(-0.0493,-0.0953)和(-0.0047,-0.0479),差异也有显著性(P<0.05)。[结论]不同价态的锰均可使心肌ΔΨM降低,产生心肌毒性;Mn3+对心肌线粒体的毒性大于Mn2+,其机制有待进一步研究。     

氦氧饱和暴露对2种菌株生长增殖的影响

目的探讨2.0MPa氦氧饱和暴露对实验菌群生长增殖状态的影响。方法采用2.0MPa高压暴露,设常压为对照,以铜绿假单胞杆菌和金黄色葡萄球菌为试验菌株,应用活菌计数方法,按不同暴露时间观察生长规律,进行比较。结果在观察的时相点内,铜绿假单胞杆菌和金黄色葡萄球菌在2.0MPa氦氧饱和暴露条件下12h出现增殖高峰,活菌菌落数量与对照组差异无统计学意义;24h菌落数量达最高峰,24～72h活菌菌落数量较常压对照组显著升高(P0.05,P0.01)。结论高气压环境暴露影响铜绿假单胞菌、金黄色葡萄球菌生长增殖。     

不同小麦面粉铁和锌吸收率的分析比较

目的分析比较不同小麦面粉中铁、锌的吸收率,为小麦的最佳制粉工艺提供参考数据。方法采用体外消化/Caco-2细胞模型模拟人体对食物的胃肠消化和吸收过程,通过测定Caco-2细胞超声破碎液中铁和锌的含量,比较2个品种(CA0045和京冬8号)、2个产地(北京和高碑店)、7种出粉率(40%、50%、60%、70%、80%、90%、100%)的小麦面粉的铁和锌吸收率。结果2个品种、2个产地、7种出粉率小麦面粉的铁、锌吸收率各不相同;面粉锌吸收率一般高于铁吸收率;铁和锌吸收率均随出粉率增高而降低;一般以40%～70%出粉率面粉的铁和锌吸收率较高,且差异不大,其中CA0045北京产小麦面粉铁和锌吸收率最高。结论CA0045和京冬8号的小麦面粉铁、锌吸收率不同;北京和高碑店两产地的小麦面粉铁、锌吸收率不同;出粉率对小麦面粉的铁、锌吸收率有影响;综合经济和营养学角度考虑,70%是小麦面粉较优的出粉率,CA0045北京产小麦是最佳品种。     

In Vitro Inhibitory Effect of Berberis vulgaris (Berberidaceae) and Its Main Component,Berberine against Different Leishmania Species

Background

Leishmaniasis has been identified as a major public health problem in tropical and sub-tropical countries. The present study was aimed to investigate antileishmanial effects of various extracts of Berberis vulgaris also its active compoenent, berberine against Leishmania tropica and L. infantum species on in vitro experiments.

Methods

In this study in vitro antileishmanial activity of various extracts of B. vulgaris also its active compoenent, berberine against promastigote and amastigote stages of L. tropica and L. infantum was evaluated, using MTT assay and in a macrophage model, respectively. Furthermore, infectivity rate and cytotoxicity effects of B. vulgaris and berberine in murine macrophage cells were investigated.

Results

The findings of optical density (OD) and IC₅₀ indicated that B. vulgaris particulary berberine significantly (P<0.05) inhibited the growth rate of promastigote stage of L.tropica and L.infantum in comparison to meglumine antimoniate (MA). In addition, B. vulgaris and berberine significantly (P<0.05) decreased the mean number of amastigotes in each macrophage as compared with positive control. In the evaluation of cytotoxicity effects, it could be observed that berberine as compared with B. vulgaris exhibited more cytotoxicity against murine macrophages. Results also showed that when parasites were pre-incubated with B. vulgaris their ability to infect murine macrophages was significantly decreased.

Conclusion

B.vulgaris particularly berberine exhibited potent in vitro leishmanicidal effects against L. tropica and L.infantum. Further works are required to evaluate the antileishmanial effects of B.vulgaris on Leishmania species using clinical settings.