超快效液相色谱与液面法测定榄香烯微乳的含量及包封率****☆

背景：超快速液相色谱法具有快速、准确的优点,可以用来检测榄香烯微乳的含量。榄香烯微乳的包封率目前尚没有较好检测方法。 目的：采用超快效液相色谱与液面法测定榄香烯微乳的含量及包封率。 方法：应用超快速液相色谱法检测榄香烯微乳含量,根据榄香烯不溶于水而浮于水面的原理,设计液面法检测榄香烯微乳的包封率。 结果与结论：色谱条件下β-榄香烯与辅料分离良好,β-榄香烯在3.94~27.58 mg/L范围内线性关系良好。榄香烯微乳中β-榄香烯平均含量为(8.273±0.018) g/L,平均包封率为(99.81±0.24)%。提示超快速液相色谱和液面法可用于检测榄香烯微乳的含量和包封率,简单、快速且准确,榄香烯微乳包封率好。     

两种中药制剂联合应用诱导K562／ADM细胞凋亡的研究

肿瘤多药耐药(multidrug resistance，MDR)的形成是多环节的复杂过程。过去逆转MDR的研究多针对耐药机制的某一环节，逆转效果受到限制。本研究试图将作用机制不同的川芎嗪(Tetramethylpyrazine，TMP)与β-榄香烯乳剂(β-elemene)联合应用实行多环节逆转，以期进一步提高逆转效果。     

榄香烯透皮凝胶的制备及体外透皮性能

背景：选择合适的载体材料对药物透皮性能的影响是制备榄香烯透皮制剂首先要解决的问题。 目的：建立一种榄香烯透皮凝胶并观察其体外透皮性能。 方法：采用具有良好生物相容性的亲水性高分子材料聚乙烯醇和羧甲基纤维素钠制备榄香烯透皮制剂。在体外透皮实验装置上,用鼠背皮肤为屏障进行经皮渗透实验,高效气相色谱检测榄香烯的经皮渗透量。 结果与结论：聚乙烯醇和羧甲基纤维素钠的使用比例对榄香烯的透皮能力没有显著影响;两种高分子骨架材料在凝胶基质中的浓度对榄香烯透皮能力有一定的影响,以30%含量(聚乙烯醇与羧甲基纤维素钠总量)为最佳。提示此种透皮凝胶可用作榄香烯的良好载体。     

β-榄香烯抑制卵巢癌细胞Cavo-3增殖的作用靶点及机制

目的研究β-榄香烯对人卵巢癌细胞Cavo-3增殖的影响及机制探索。方法体外培养卵巢癌Cavo-3细胞,用MTT实验和集落形成实验检测β-榄香烯对卵巢癌Cavo-3细胞增殖的影响,Western blot实验检测β-榄香烯对Cavo-3细胞EGFR及其下游信号通路的影响。结果β-榄香烯以浓度和时间依赖性方式抑制卵巢癌Cavo-3细胞的增殖;Western blot实验发现β-榄香烯能显著抑制EGFR及其下游通路磷酸化水平,而不影响总蛋白水平。结论β-榄香烯通过EGFR信号通路抑制卵巢癌Cavo-3细胞的增殖,揭示了β-榄香烯发挥抗卵巢癌作用的新机制。     

榄香烯增强瘤苗免疫原性的研究

目的 在基因水平上通过与热休克处理对比探讨榄香烯增强肿瘤细胞免疫原性的分子机制。方法 人肝癌细胞HepG2经50μg/ml榄香烯或42℃热休克处理后，与未经处理的对照组一起，分别提取总RNA、逆转录成cDNA、体外转录制备生物素标记的cRNA，应用含有12550条人类基因的表达谱芯片，与热休克对比分析经榄香烯处理的人肝癌细胞HepG2基因表达谱的改变。结果 榄香烯能使HepG2细胞的24条基因表达明显改变，在这24条基因中有14条基因在热休克处理时未发生表达变化。结论 榄香烯有可能在基因水平上改变肿瘤细胞的免疫原性，并可能诱生与热休克不同的免疫原性物质。     

榄香烯复合瘤苗HSP70与卡介苗HSP70免疫效应机制的对比研究

分别从榄香烯复合瘤苗及卡介苗中提取纯化HSP70，并以榄香烯复合瘤作为阳性对照，通过测定免疫小鼠全脾细胞的细胞增殖周期、细胞表型、细胞毒活性，研究两者在免疫效应及机制上的不同之处。     

β-榄香烯对胃癌耐药细胞裸鼠移植瘤生长的影响

目的观察中药β-榄香烯对胃癌耐药细胞株SGC-7901/Adr裸鼠成瘤能力的影响,探讨β-榄香烯对胃癌耐药细胞的作用及机制。方法利用MTT实验验证SGC7901/Adr细胞的耐药性及β-榄香烯的毒性作用,利用裸鼠移植瘤模型分析β-榄香烯对胃癌耐药细胞裸鼠移植瘤生长的影响,利用免疫组织化学方法检测各组移植瘤组织中Caspase-3蛋白的表达水平。结果相对于SGC7901细胞,SGC7901/Adr细胞对ADR具有耐药性;β-榄香烯对SGC7901/Adr细胞具有增殖抑制作用,且具有浓度依赖性。β-榄香烯能够较好地抑制胃癌耐药细胞裸鼠移植瘤的生长,能够明显缩小肿瘤体积。β-榄香烯处理后,移植瘤组织中Caspase-3蛋白表达有上升趋势。结论β-榄香烯促进肿瘤细胞凋亡、抑制胃癌耐药细胞裸鼠移植瘤的生长与上调Caspase-3蛋白表达水平相关。     

β—榄香烯,丝裂霉素C及热休克对小鼠H22肝癌细胞HSP70表达？…

为了进一步阐明肿瘤２疫苗的特异性主动免疫治疗机理，采用β－榄香烯，丝裂霉素及热休克在体外单独及复合处理小鼠Ｈ２２肝癌细胞，经间接免疫荧光染色，流式细胞仪分析，结果显示，上述处理因素均能明显地诱导Ｈ２２细胞表达ＨＳＰ７０，在单因素中，以β－榄香烯效果最佳，阳性率为６９．１６％，ＭＭＣ次之，在复合因素中，以β－榄香烯与ＭＭＣ复合处理的效果最佳，阳性率为９５．１３％；三种因素联合处理的效果为８５．３４％     

榄香烯对人癌细胞增殖的抑制作用

应用MTT法检测42例癌症患者肿瘤细胞对抗癌药榄香烯的敏感性,并与其他7种化疗药物加以比较。结果表明在一定剂量范围内榄香烯对正常细胞无明显影响但有20例（占47.6％）肿瘤细胞对榄香烯敏感;不同肿瘤对该药的敏感性差异较大,同一类型肿瘤的不同个体敏感性也不相同。     

β-榄香烯对EAE小鼠视神经炎治疗作用的研究

目的:研究β-榄香烯(β-elemene)对实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)小鼠视神经炎的治疗作用;明确β-榄香烯如何通过对辅助性T细胞亚群的分化调节及其特异性细胞因子的转录调节实现其治疗作用。方法:通过行为学、组织形态学技术观察β-榄香烯对EAE小鼠脱髓鞘性视神经炎的治疗作用,进一步通过ELISA及定量PCR技术观察β-榄香烯对辅助性T细胞亚群特异性细胞因子及转录因子的蛋白及mRNA表达的影响。结果:β-榄香烯能改善EAE小鼠的神经功能评分(与对照组比较,P<0.05);β-榄香烯能减轻EAE小鼠视神经轴索及髓鞘损伤;免疫后11天,β-榄香烯可减少EAE小鼠视神经细胞因子白细胞介素-17(IL-17)、转录因子孤儿核受体(RORγt)的蛋白及mRNA的表达(与对照组比较,P<0.05);同时增加叉头蛋白3(Foxp3)mRNA的表达(与对照组比较,P<0.05)。免疫后19天,β-榄香烯可减少EAE小鼠视神经细胞因子γ-干扰素(IFN-γ)、转录因子T-bet的蛋白及mRNA的表达(与对照组比较,P<0.05);并维持Foxp3mRNA的较高水平表达(与对照组比较,P<0.05)。结论:β-榄香烯可减轻EAE小鼠视神经的炎症损伤;β-榄香烯可通过调节辅助性T细胞亚群的分化维持机体的免疫平衡。     

榄香烯对人胶质瘤U251细胞的放射增敏机制

目的:探讨榄香烯对人胶质瘤U251细胞的放射增敏机制。方法:以U251细胞系为离体胶质瘤模型,用不同浓度榄香烯和不同放射剂量分别处理U251细胞,采用MTT实验检测细胞活力,流式细胞术检测细胞凋亡及细胞周期,Western blot检测相关蛋白的表达水平。结果:榄香烯对U251细胞具有生长抑制及放射增敏作用;放疗联合榄香烯组U251细胞较放射组有更高的早期凋亡率、继发性坏死率和总死亡率;榄香烯能诱导U251细胞G2/M期阻滞;榄香烯通过降低细胞分裂周期蛋白2(Cdc2)表达,导致放疗诱导的cyclin B1表达降低,从而抑制cyclin B-Cdc2复合物形成;同时抑制Cdc2蛋白第161位苏氨酸磷酸化,降低Cdc2的活性,从而诱导细胞G2/M期阻滞;另外可能通过下调survivin表达,介导细胞凋亡。结论:榄香烯可能通过下调Cdc2蛋白、降低cyclin B1表达、抑制cylcin B-Cdc2复合物的形成、下调survivin表达等方面增强U251细胞对放疗的敏感性。     

The effect of elemene on lung adenocarcinoma A549 cell radiosensitivity and elucidation of its mechanism

OBJECTIVE:

To investigate the effect of elemene on the radiosensitivity of A549 cells and its possible molecular mechanism.

METHODS:

Apoptosis of A549 cells was detected by flow cytometry and fluorescence microscopy. The effect of double-strand break (DSB) damage repair in A549 cells was evaluated using the neutral comet assay. Protein expression levels were detected using western blotting, and the correlation between protein levels was analyzed.

RESULTS:

Elemene exhibited a radiosensitizing effect on A549 cells. The level of apoptosis induced by elemene combined with radiation was significantly greater (p<0.01) than that elicited by either radiation or elemene alone. Following radiation and subsequent repair for 24 h, the tail intensity of A549 cells treated with a combination of elemene and radiation was greater than that of cells treated with either elemene or radiation alone (p<0.01). This result indicates that elemene inhibits cellular DSB repair. Both elemene combined with radiation and radiation alone decreased the protein expression of DNA-PKcs and Bcl-2 compared to elemene alone (p<0.01), while p53 protein expression was increased (p<0.01). A negative correlation was observed between DNA-PKcs and p53 expression (r=-0.569, p=0.040), while a positive correlation was found between DNA-PKcs and Bcl-2 expression (r=0.755, p=0.012).

CONCLUSIONS:

Elemene exhibits a radiosensitizing effect on A549 cells, and its underlying molecular mechanism of action may be related to the downregulation of DNA-PKcs gene expression.     

Experimental study on the effect and mechanism of action of active immunization with elemene combo-tumor cell vaccine

Experimental study on the effect and mechanism of action of active immunization with elemene combo-tumor cell vaccine     

口服榄香烯微乳的制备与表征***☆

背景：研究显示,微乳可保护稳定性差的药物,增加难溶性药物的溶解度,提高生物利用度,控制药物释放及减少用药个体差异等。其主要缺点在于需要较多的表面活性剂和助表面活性剂,对人体的安全性是一个重要挑战。 目的：探讨榄香烯微乳的制备方法,并对其结构与性能进行表征。 方法：榄香烯药物直接作为油相,吐温80作为表面活性剂,乙醇、丙二醇、甘油作为助表面活性剂,采用超声法制备成榄香烯微乳。 结果与结论：榄香烯微乳粒径为(67±13) nm,Zeta电位为(3.2±0.4) mV,pH值为5.16,黏度为6 mPa•s,表面张力为      31.7 mN/m。榄香烯微乳中β-榄香烯含量为(8.273±0.018) g/L,平均包封率为(99.81±0.24)%。结果可见该方法制备的榄香烯微乳粒径小,分布窄,呈弱酸性,黏度低,表面张力较低,体系稳定性好,适用于口服给药。     

Combined Linkage and Association Mapping of Quantitative Trait Loci with Missing Completely at Random Genotype Data

In genetics study, the genotypes or phenotypes can be missing due to various reasons. In this paper, the impact of missing genotypes is investigated for high resolution combined linkage and association mapping of quantitative trait loci (QTL). We assume that the genotype data are missing completely at random (MCAR). Two regression models, “genotype effect model” and “additive effect model”, are proposed to model the association between the markers and the trait locus. If the marker genotype is not missing, the model is exactly the same as those of our previous study, i.e., the number of genotype or allele is used as weight to model the effect of the genotype or allele in single marker case. If the marker genotype is missing, the expected number of genotype or allele is used as weight to model the effect of the genotype or allele. By analytical formulae, we show that the “genotype effect model” can be used to model the additive and dominance effects simultaneously, and the “additive effect model” can only be used to model the additive effect. Based on the two models, F-test statistics are proposed to test association between the QTL and markers. The non-centrality parameter approximations of F-test statistics are derived to calculate power and to compare power, which show that the power of the F-tests is reduced due to the missingness. By simulation study, we show that the two models have reasonable type I error rates for a dataset of moderate sample size. However, the type I error rates can be very slightly inflated if all individuals with missing genotypes are removed from analysis. Hence, the proposed method can help to get correct type I error rates although it does not improve power. As a practical example, the method is applied to analyze the angiotensin-1 converting enzyme (ACE) data. Edited by Pak Sham.     

Periodic breathing induced by arterial oxygen partial pressure oscillations.

The Grodins model of respiratory control (Grodins et al., 1967) describes cardio-respiratory control for a lung with homogeneous gas concentrations. In this study we modify the Grodins model to take account of the inhomogeneities in gas concentration within the lung that are seen in many subjects with respiratory illnesses. This modification has the effect of lowering arterial oxygen partial pressure significantly. We investigate the effect on cardio-respiratory control of this low arterial oxygen signal and find that the governing equations may be reduced to a single delay-differential equation. This reduced model is found to be a good approximation to the full model and gives predictions that are similar to reported clinical data.     

Use of azole compounds for the treatment of experimental aspergillosis in turkeys

A model for aspergillosis by injecting fungal spores into the lung is described. The model permits evaluation of anti-mycotic agents and their effect on the development of lesions in the infected lung, the spreading to the second lung and other organs. The therapeutic effect of the azole compounds enilconazole, ketoconazole, itraconazole and levamisole was determined. Itraconazole was found to be the most effective.     

氯化钴预适应对大鼠局灶性脑缺血的保护作用

目的探讨氯化钴预适应对大鼠局灶性脑缺血的保护作用及对nNOS基因表达的调节。方法建立线栓法大鼠局灶性脑缺血的动物模型,以30μg/kg氯化钴预处理大鼠,以TTC染色方法观察脑缺血范围,并以RT-PCR法检测nNOS基因的表达情况。结果氯化钴预适应能显著降低大鼠的脑梗塞面积,起到保护作用,并上调nNOS基因的表达,而nNOS阻滞剂7-NI可明显降低预适应的保护作用。结论氯化钴预适应可以对大鼠局灶性脑缺血起到保护作用,对nNOS基因的调节作用可能是其机制之一。     

Interseed effects on dose for 125I brachytherapy implants.

Dose calculations in multiseed brachytherapy implants are done by adding the contribution of each individual seed and by assuming that radiation from each seed is unaffected by the presence of the other seeds. To test the validity of this assumption, dose measurements with various configurations of multiseed implants of 125I model 6702 and 125I model 6711 sources were performed. For a linear configuration of three 125I model 6702 seeds at 1-cm separation, with their transverse axes coincident, doses at distances of 3.05 and 5.09 cm from the center along the transverse axis were found to be about 8% lower than the sum of doses from the three individual seeds. However, for three seeds at 1-cm intervals with their longitudinal axes coincident, doses at 3.05 and 5.09 cm distances from the center along the longitudinal axis were found to be about equal to the dose sums from individual seeds. These initial experiments indicated that the magnitude of the interseed effect depends upon the orientation of the seed relative to each other in an implant. To evaluate the importance of this interseed effect for multiseed configurations of 125I model 6702 and 125I model 6711 seeds, dose rates at various distances from a two-plane implant (each plane containing a 3 x 3 array of sources in a 1-cm spacing square grid) were measured in a Solid Water phantom with LiF TLDs. These measurements were carried out in two different planes at different orientations relative to the implant. The average values of the interseed effect at distances ranging from 1 to 7 cm outside the implant were observed to be about the same for 125I model 6702 and model 6711 sources. The mean value of the interseed effect was 6% and the maximum was 12%. On the whole, the interseed effect reduces the dose at the periphery of the iodine implant by 6%.