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目的 建立云芝胞内糖肽的游离糖和水解单糖指纹图谱和含量测定的检测方法。方法 游离糖测定以水为溶剂超声提取后PMP衍生化,水解单糖测定酸水解后PMP衍生化,采用HPLC对来自不同企业的云芝胞内糖肽原料、中间体的游离糖和水解单糖进行定性和定量分析。通过化学计量学分析对指纹图谱进行了分析,探讨不同生产企业生产的云芝胞内糖肽差异性。结果 2种方法均通过方法学验证;不同企业的样品分别聚类,有3种游离糖和2种水解单糖对云芝胞内糖肽的质量差异贡献较大。结论 建立的分析方法可有效用于云芝胞内糖肽中游离糖和水解后的单糖的测定和指纹图谱研究,采用的化学计量学研究方法对云芝胞内糖肽的质量控制提供了指导意义。 相似文献
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目的:探讨云芝糖肽辅助化疗药多柔比星协同增效的机制。方法:CCK-8检测云芝糖肽影响多柔比星在AGS胃癌细胞中细胞毒性的作用;LC-MS/MS法检测云芝糖肽对多柔比星在AGS细胞内累积的影响;RT-PCR检测云芝糖肽对AGS细胞P-gp的mRNA表达的影响;流式细胞术检测云芝糖肽对AGS细胞表面P-gp蛋白表达的影响。结果:云芝糖肽能显著增加多柔比星对AGS胃癌细胞的毒性;中、高浓度(0.5、1.0 mg·mL-1)的云芝糖肽显著增加多柔比星在AGS胃癌细胞内的累积;中、高浓度(0.5、1.0 mg·mL-1)的云芝糖肽显著减少AGS胃癌细胞p-gp mRNA的表达,显著减少AGS胃癌细胞表面P-gp蛋白的表达。结论:云芝糖肽能提高多柔比星在AGS细胞上的药效,其机制可能与减少细胞P-gp表达有关,减少了多柔比星在肿瘤细胞的外排,增加胞内浓度,从而提高药效。 相似文献
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目的:探讨云芝糖肽辅助化疗药多柔比星协同增效的机制。方法:CCK-8检测云芝糖肽影响多柔比星在AGS胃癌细胞中细胞毒性的作用;LC-MS/MS法检测云芝糖肽对多柔比星在AGS细胞内累积的影响;RT-PCR检测云芝糖肽对AGS细胞P-gp的mRNA表达的影响;流式细胞术检测云芝糖肽对AGS细胞表面P-gp蛋白表达的影响。结果:云芝糖肽能显著增加多柔比星对AGS胃癌细胞的毒性;中、高浓度(0.5、1.0 mg·mL-1)的云芝糖肽显著增加多柔比星在AGS胃癌细胞内的累积;中、高浓度(0.5、1.0 mg·mL-1)的云芝糖肽显著减少AGS胃癌细胞p-gp mRNA的表达,显著减少AGS胃癌细胞表面P-gp蛋白的表达。结论:云芝糖肽能提高多柔比星在AGS细胞上的药效,其机制可能与减少细胞P-gp表达有关,减少了多柔比星在肿瘤细胞的外排,增加胞内浓度,从而提高药效。 相似文献
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目的:建立高效液相色谱-紫外检测(HPLC-UV)法测定雷诺嗪缓释片的含量。方法:样品经流动相超声提取后,采用Diamonsil TM C18(250 mm×4.6 mm,5μm)分析柱,甲醇-含醋酸铵20 mmol.L-1和醋酸10 mmol.L-1的水溶液(60∶40)为流动相,检测波长为272 nm。结果:雷诺嗪在20.90~62.70μg.mL-1范围内线性关系良好,平均提取回收率为100.0%,批内精密度RSD小于1.0%。结论:所建立的方法操作简便,准确,适合雷诺嗪制剂的含量测定。 相似文献
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毛细管气相色谱法测定云芝糖肽的单糖组成 总被引:3,自引:0,他引:3
目的:对多孔菌科真菌云芝的的活性成分云芝糖肽的单糖组成进行研究。方法:从云芝中提取得到云芝糖肽精品,经三氟乙酸水解后用硼氢化钠还原,然后对其进行乙酰化衍生化,用标准单糖作为对照,肌醇为内标,产物用气相色谱法分析,色谱条件为程序升温:180 T(2min)3℃·min~(-1)230℃(20 min)。结果:云芝糖肽的单糖组成为葡萄糖、半乳糖、甘露糖、岩藻糖、鼠李糖、木糖,其摩尔比为0.544:0.188:0.180:0.062:0.009:0.18。结论:建立了毛细管气相色谱测定云芝糖肽的单糖组成的方法,并得到云芝糖肽的单糖组成的结果。 相似文献
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目的 建立高效液相色谱-二极管阵列检测法测定甘草酸含量的方法,并采用正交设计和均匀设计试验优化炙甘草中甘草酸的提取工艺.方法 色谱条件:Agilent Zorbax SB C18分析柱(4.6 mm×250.0 mm,5μm),流动相为乙腈-2%醋酸溶液(体积比37:63),检测波长254 nm,流速1.0 ml/min,柱温30℃,进样量10μl.以甘草酸的含量为指标,对固液比例、浸泡时间和超声时间等因素进行优化.使用统计学方法分析试验结果,并进行验证试验.结果 通过对两种试验设计方法提取效果的比较,结合实际情况,确定炙甘草中甘草酸的最优提取条件为加160倍甲醇,浸泡60 min.超声处理15 min.结论 正交设计和均匀设计试验可以简便、快速的优化炙甘草中甘草酸的提取条件,同时使用还可提高试验结果的可信度. 相似文献
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《Journal of addictive diseases》2013,32(3):73-87
Depression and anxiety frequently coexist in patients with substance use disorders. This clinically-oriented article examiens the relationship between these conditions and emphasizes data showing that substances of abuse can cause signs and symptoms of both depression and anxiety. These substance-related syndromes appear to have a different course and prognosis than uncomplicated, independent anxiety and major depressive disorders, and clinicians should consider the role of alcohol and other drugs in all patients presenting with these complaints. The authors will also outline an approach for diagnosing and managing patients with the combination of a substance use and depressive or anxiety disorder. 相似文献
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The synthesis of gaultherin (1) and its analogs was carried out to provide 11 glycosides under phase-transfer catalytic conditions. The activities of all synthesized compounds were evaluated by nitric oxide production inhibitory assay in vitro. Methyl 2-O-(4-O-β-d-galactopyranosyl)-β-d-glucopyranosylbenzoate (5f) showed significantly anti-nociceptive and anti-inflammatory effects by the evaluation in vivo. Structure–activity relationships within these compounds were discussed. 相似文献
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Nestorov I 《Toxicology letters》2001,120(1-3):411-420
Two important methodological issues within the framework of the variability and uncertainty analysis of toxicokinetic and pharmacokinetic systems are discussed: (i) modelling and simulation of the existing physiologic variability in a population; and (ii) modelling and simulation of variability and uncertainty when there is insufficient or not well defined (e.g. small sample, semiquantitative, qualitative and vague) information available. Physiologically based pharmacokinetic models are especially suited for separating and characterising the physiologic variability from the overall variability and uncertainty in the system. Monte Carlo sampling should draw from multivariate distributions, which reflect all levels of existing dependencies in the intact organism. The population characteristics should be taken into account. A fuzzy simulation approach is proposed to model variability and uncertainty when there is semiquantitative, qualitative and vague information about the model parameters and their statistical distributions cannot be defined reliably. 相似文献
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The effects of the d and l isomers of amphetamine on self-stimulation responding were tested following acute and chronic administration. Tolerance and post-drug depression of responding occurred in tests with both isomers, indicating no role for p-hydroxynorephedrine (PHN) which is one of the metabolites of d-amphetamine. In the second experiment, d-amphetamine, methylphenidate and cocaine all produced quantitatively and qualitatively similar effects on self-stimulation responding following acute administration. Following chronic administration of d-amphetamine, animals showed tolerance to all three drugs, indicating cross-tolerance among them. These data are consistent with an hypothesis that tolerance and post-drug depression following chronic amphetamine treatment are the result of decreases in postsynaptic receptor sensitivity, which would lead to a decreased effectiveness of all three drugs, regardless of their pre-synaptic mechanisms. 相似文献
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Rationale Two pharmacotherapies are approved for treating alcohol craving (acamprosate and naltrexone), but both have shown mixed findings
in animals and humans.
Objectives The present experiments utilized a “reinforcer blocking” approach (i.e., rats were able to consume ethanol during treatment)
to better understand the efficacy of these treatments for ethanol seeking and drinking using ethanol-dependent and nondependent
rats.
Materials and methods In “nondependent” experiments, drugs (acamprosate 50, 100, and 200 mg/kg; naltrexone 0.1, 0.3, and 1.0 mg/kg) were administered
over 3-week periods prior to operant sessions with a low response requirement to gain access to reinforcers for 20 min. For
“dependent” experiments, rats were made dependent in vapor/inhalation chambers.
Results Acamprosate and naltrexone had similar effects on intake in nondependent and dependent rats; neither drug was selective for
ethanol over sucrose drinking. In nondependent animals, naltrexone was more efficacious at more doses than acamprosate, and
acamprosate’s effects were limited to a dose that also had adverse effects on body weight. Both pharmacotherapies showed more
selectivity when examining reinforcer seeking. In nondependent rats, acamprosate and naltrexone had response-attenuating effects
in ethanol, but not sucrose, groups. In dependent animals, acamprosate had selective effects limited to a decrease in sucrose
seeking. Naltrexone, however, selectively decreased ethanol-seeking in nondependent rats.
Conclusions The naltrexone-induced decreases in seeking suggested a change in incentive motivation which was selective for ethanol in
nondependent rats. The “nondependent” paradigm may model early stages of “problem drinking” in humans, and the findings suggest
that naltrexone could be a good intervention for this level of alcohol abuse and relapse prevention. 相似文献
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Max Caviezel Werner K. Lutz Urs Minini Christian Schlatter 《Archives of toxicology》1984,55(2):97-103
[6,7-3H] Estrone (E) and [6,7-3H]estradiol-17 (E2) have been synthesized by reduction of 6-dehydroestrone and 6-dehydroestradiol with tritium gas. Tritiated E and E2 were administered by oral gavage to female rats and to male and female hamsters on a dose level of about 300 g/kg (54 mCi/kg). After 8 h, the liver was excised from the rats; liver and kidneys were taken from the hamsters. DNA was purified either directly from an organ homogenate or via chromatin. The radioactivity in the DNA was expressed in the units of the Covalent Binding Index, CBI = (mol chemical bound per mol DNA-P)/(mmol chemical administered per kg b.w.). Rat liver DNA isolated via chromatin exhibited the very low values of 0.08 and 0.09 for E and E2, respectively. The respective figures in hamster liver were 0.08 and 0.11 in females and 0.21 and 0.18 in the males. DNA isolated from the kidney revealed a detectable radioactivity only in the female, with values of 0.03 and 0.05 for E and E2, respectively. The values for male hamster kidney were < 0.01 for both hormones. The minute radioactivity detectable in the DNA samples does not represent covalent binding to DNA, however, as indicated by two sets of control experiments. (A) Analysis by HPLC of the nucleosides prepared by enzyme digest of liver DNA isolated directly or via chromatin did not reveal any consistent peak which could have been attributed to a nucleoside-steroid adduct. (B) All DNA radioactivity could be due to protein contaminations, because the specific activity of chromatin protein was determined to be more than 3,000 times higher than of DNA. The high affinity of the hormone to protein was also demonstrated by in vitro incubations, where it could be shown that the specific activity of DNA and protein was essentially proportional to the concentration of radiolabelled hormone in the organ homogenate, regardless of whether the animal was treated or whether the hormone was added in vitro to the homogenate.Carcinogens acting by covalent DNA binding can be classified according to potency on the basis of the Covalent Binding Index. Values of 103–104 have been found for potent, 102 for moderate, and 1–10 for weak carcinogens. Since estrone is moderately carcinogenic for the kidney of the male hamster, a CBI of about 100 would be expected. The actually measured limit of detection of 0.01 places covalent DNA binding among the highly unlikely mechanisms of action. Similar considerations can be made for the liver where any true covalent DNA binding must be below a level of 0.01. It is concluded that an observable tumor induction by estrone or estradiol is unlikely to be due to DNA binding.Paper presented at the Satellite Symposium of the European Society of Toxicology, Rome, March 29, 1983 相似文献
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Schierholz JM Yücel N Rump AF Beuth J Pulverer G 《International journal of antimicrobial agents》2002,19(6):81-516
Catheters, urethral and ureteral stents and other urological implants are frequently affected by encrustration and infection due to their permanent contact with urine. Indwelling urinary catheters provide a haven for microorganisms and thus require extensive monitoring. Several surface modification techniques have been proposed to improve the performance of devices including the immobilization of biomolecules, the incorporation of hydrophilic grafts to reduce protein adsorption, the creation of hydrophobic surfaces, the creation of microdomains to regulate cellular and protein adhesion, new polymers and antimicrobial coatings. Physico-chemical explanation to elucidate the mechanism of such encrustation or infection inhibiting materials is still not available. Our series of experiments showed a marked decrease of silver-activity in biological fluids which corresponds with the controversial clinical results obtained with silver coated urinary catheters. Rifampicin/minocycline coated catheters had very low activity against Gram-negative rods, enterococci and Candida spp., the main causing organisms of urinary catheter infection. Surface engineered materials and antimicrobial drug delivery systems will be the next generation of sophisticated urinary catheters and stents, if both efficacy as well as efficiency has been proved clinically. 相似文献