高效液相色谱法测定间尼索地平不同对映体在血浆中的蛋白结合率

目的:建立间尼索地平不同对映体在大鼠血浆、人血浆和牛血清白蛋白中蛋白结合率的测定方法,并计算不同种属血浆蛋白的相关参数。方法:采用平衡透析法测定蛋白结合率,用高效液相色谱法测定血浆中药物总浓度及游离药物浓度。结果:R-与S-间尼索地平的血浆蛋白结合率分别为:大鼠血浆为(97.4±8.2)%、(93.0±13.4)%;人血浆为(90.8±10.5)%、(89.2±9.9)%;牛血清白蛋白为(95.3±8.7)%、(91.0±5.7)%。最低定量下限为0.01ng。结论:在体外间尼索地平不同对映体与大鼠血浆、人血浆和牛血清白蛋白结合率很高,R-间尼索地平的结合率及蛋白结合药物的表观最大能力βp均较S-间尼索地平高。随着药物血浆浓度升高,R-间尼索地平结合率下降,S-间尼索地平结合率升高,均有一定的浓度依赖性。     

间尼索地平消旋体在大鼠血浆中的蛋白结合率及其肠吸收动力学研究

目的:研究间尼索地平消旋体在大鼠血浆中的蛋白结合率及其肠吸收动力学。方法:采用平衡透析法和高效液相色谱(HPLC)法测定尼索地平消旋体(0.2、0.5、1.0、2.0μg/ml)在大鼠血浆中的蛋白结合率,并计算白蛋白结合药物的表观最大能力(βp)和药物-蛋白复合物的解离常数(Kdp)。采用大鼠在体小肠回流实验装置,利用HPLC法同时测定十二指肠、空肠、回肠、结肠的肠循环液中间尼索地平消旋体及酚红的含量以计算4h药物吸收百分率,并探讨不同药物浓度、pH值和吐温80对肠吸收的影响。结果:0.2、0.5、1.0、2.0μg/ml尼索地平消旋体在大鼠血浆中的蛋白结合率分别为(96.38±3.6)%、(97.13±3.1)%、(97.27±2.8)%、(98.22±3.6)%,βp为4×10-4μmol/g,Kdp为7×10-4μmol/L。间尼索地平消旋体在十二指肠、空肠、回肠、结肠的4h吸收百分率分别为(51.26±1.09)%、(47.85±6.25)%、(43.63±1.986)%、(39.87±5.42)%,不同pH的肠循环液和不同浓度吐温80对其小肠吸收百分率无明显影响(P>0.05),其浓度与其小肠吸收百分率呈线性关系。结论:间尼索地平消旋体与大鼠血浆蛋白结合率很高,且呈浓度依赖性;其在全肠段吸收呈一级动力学方程,吸收机制为被动扩散。     

液质联用分析间尼索地平消旋体大鼠组织分布特征

目的：利用液质联用技术研究大鼠体内间尼索地平消旋体的组织分布特征。方法20℃下,利用C18柱,以乙腈-水（70∶30, v／v）为流动相,流速为0破．8 ml／min,检测波长237 nm。扫描方式采用多重反应监测,离子化模式采用ESI选择性负离子检测。组织匀浆液采用正己烷-乙醚（1∶1）萃取,进样LC-MS-MS分析。结果大鼠灌胃给予间尼索地平消旋体20 mg／kg后,在大鼠小肠、肺和肝中,30和150 min的分布量均较90 min高,在脑组织中也有一定的分布。结论本法灵敏度高,操作方便,适合于大鼠体内间尼索地平消旋体的组织分布研究,为其临床实验研究与新药申报提供了理论依据。     

RP—HPLC法研究间尼索地平2种晶型在大鼠体内的组织分布特征

目的:采用高效液相色谱法研究2种晶型间尼索地平在大鼠体内的组织分布特征。方法:生物样品在碱性条件下,加入内标尼莫地平,经乙酸乙酯提取后,进行 HPLC 测定。色谱柱为 Diamonsil~(TM)C_(18)柱(250 mm×4.6 mm,5μm);流动相为乙腈-水(62:38),流速1.0 mL·min~(-1);检测波长237 nm。结果:大鼠在口服 A 和 B 两种晶型间尼索地平(30 mg·kg~(-1))后,于10,30,150 min处死,两种晶型在30 min 时组织中浓度较高,150 min 时在除肺外的各脏器中浓度均呈下降趋势。组织匀浆中间尼索地平的线性关系、最低检测限、准确度和精密度均符合分析要求。结论:该法测定大鼠各组织中药物浓度准确、灵敏、可靠,为问尼索地平新药研究与开发提供实验依据。     

经皮给药后尼索地平在大鼠体内血药浓度的LC-MS法测定

建立了液相色谱-质谱法测定大鼠血浆中的尼索地平,并考察尼索地平微乳凝胶经皮给药后在大鼠体内的药动学.采用电喷雾离子源(ESI源),正离子检测,选择离子监测(SIM),监测离子对为m/z 411(尼索地平)和m/z 441(尼莫地平,内标).血浆中尼索地平在0.5～50 ng/ml浓度范围内线性关系良好,方法回收率为95％～102％,RSD≤5.8％.血浆中药物的提取回收率大于70％.采用雄性SD大鼠考察微乳凝胶经皮给药后的体内药动学行为并与口服混悬剂进行比较.含尼索地平20 mg的微乳凝胶经皮给药后的主要药动学参数分别为tmx (42.00±6.92)h,cmax (27.53±1.88) ng/ml,AUC0→72h(1736.31±106.59) ng·h·ml1,AUC0→∞(1999.66±119.26) ng·h·ml-1,MRT (44.02±0.77)h和t1/2 (7.61±0.70)h.     

HPLC-MS-MS测定犬血浆中间尼索地平含量

目的：利用HPLC-MS-MS测定Beagle犬血浆中间尼索地平的含量，并计算药动学参数。方法利用Symmetry C18柱，20℃下，以乙腈-水（70∶30，v／v）为流动相，流速为0A．8ml／min，检测波长237nm。采用负离子多离子反应监测，用于定量分析的离子反应为m／z387．0→m／z122．0。血浆样品采用乙腈沉淀蛋白，进样质谱分析。结果方法的最低定量下限为0．25ng／ml；间尼索地平检测浓度在0．25～20ng／ml的范围内线性关系良好（r＝0．9943）。药代动力学参数：Cmax为（13．86±3．12）ng／ml，Tmax为（2．6±2．25）h，t1／2为（9．37±2．74）h，ke为（1．24±0．52）×10－3，AUC0-t为（88．46±4．79）ng·h－1·ml－1，AUC0-∞为（98．35±1．89）ng·h－1·ml－1。结论本法灵敏度高，操作方便，适合于Beagle犬血浆中间尼索地平的药动学研究。     

人血浆中尼索地平浓度的LC-MS测定

建立了LC—MS法测定人血浆中尼索地平的浓度。血浆在碱性条件下用乙醚-正己烷(1：1)提取，以尼莫地平为内标，采用Inertsil C18色谱柱，AP—ESI质谱检测器，正离子模式，采集方式为SIM。流动相为甲醇-水-醋酸(75：25：0．1)。尼索地平在O．2～40ng／ml范围内线性关系良好，提取回收率大于80％，RSD小于10％，定量限为O．2ng／ml。     

大鼠肠内菌转化间尼索地平的代谢产物

应用LC-MS/MS法研究肠内菌转化间尼索地平的代谢产物.将间尼索地平与大鼠肠内菌于体外厌氧温孵培养,放大制备转化产率最高的代谢物.依据1H NMR和ESI-MS/MS数据确认代谢物结构,推断可能的代谢途径.结果在温孵液中发现了间尼索地平及其2种代谢产物.     

大鼠肝微粒体中间尼索地平的HPLC法测定与酶促反应动力学

建立了HPLC法测定大鼠肝微粒体中的间尼索地平及相应的酶促反应动力学。采用C18色谱柱,乙腈-水（62∶38）为流动相,检测波长237nm,样品经氢氧化钠溶液碱化后用乙醚-正己烷（1∶1）萃取。间尼索地平在1.56～100μmol/L浓度范围内线性关系良好。本法的相对回收率为93.0%,RSD为3.75%;日内、日间RSD分别为6.04%和1.53%。     

间-尼索地平对大鼠急性肺损伤的保护作用

目的观察新型钙拮抗剂间-尼索地平对脂多糖（LPS）诱导大鼠急性肺损伤（ALl）是否有保护作用,探讨Au治疗的新思路。方法以LPS（5．0mg／kg）尾静脉注射建立肺损伤模型。观察各组大鼠肺组织病理改变,计算肺W／D值,检测肺泡上皮细胞内Ca2＋浓度,测定支气管-肺泡灌洗液（BALF）中肿瘤坏死因子α（TNF—α）和蛋白质含量,肺组织中丙二醛（MDA）含量,肺毛细血管通透指数（CPI）的变化。结果间-尼索地平能明显减轻LPS所致ALl模型肺组织病变情况。间-尼索地平组肺泡上皮细胞Ca2＋浓度比LPS组含量明显减少（P〈0．05）,肺W／D值比LPS组明显降低（P〈O．05）,肺CPI比LPS组明显降低（P〈0．01）,肺组织MDA含量比LPS组含量减少（P〈0．01）。结论间-尼索地平对脂多糖肺损伤有一定的保护作用。     

Affective and Anxiety Disorders and Alcohol and Drug Dependence:

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.     

Synthesis and anti-nociceptive and anti-inflammatory effects of gaultherin and its analogs

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.     

Modelling and simulation of variability and uncertainty in toxicokinetics and pharmacokinetics

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.     

成骨细胞的功能与损伤和骨质疏松的防治

骨质疏松是一种全身性骨骼疾病,导致骨折风险增加。成人的骨量通过破骨细胞的骨吸收和成骨细胞的骨形成作用来维持动态平衡,治疗骨质疏松症的理想策略是抑制破骨细胞的骨吸收和/或增强成骨细胞的骨形成功能。目前针对保护成骨细胞及增强其功能的骨质疏松疗法相对较少。因此,本文针对成骨细胞相关功能蛋白、各种细胞损伤机制（内质网应激、氧化应激、机械过载、微小RNA和长链非编码RNA的影响等）及骨质疏松的治疗与预防作一综述,以期为针对增强成骨细胞功能的骨质疏松治疗策略提供新思路。     

Self-stimulation and amphetamine: Tolerance to d and l isomers and cross tolerance to cocaine and methylphenidate

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.     

益生菌与肿瘤防治

益生菌广泛存在于自然界中,通过维持宿主体内菌群平衡、影响肠屏障功能和调节免疫应答等作用,提高宿主健康水平,被公认为"肠道健康卫士".一些益生菌可以增强机体的免疫功能,抑制致癌物质,影响肿瘤细胞的基因表达,对肿瘤具有拮抗作用.大量研究表明,益生菌在未来的肿瘤防治中有很好的应用和发展前景.     

Acamprosate and naltrexone treatment effects on ethanol and sucrose seeking and intake in ethanol-dependent and nondependent rats

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.     

Antiinfective and encrustation-inhibiting materials--myth and facts

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.     

Alprazolam and lorazepam single and multiple-dose effects on psychomotor skills and sleep

Summary The effects of alprazolam 0.5 mg and lorazepam 2 mg on cognitive and psychomotor skills were assessed in twelve normal volunteer subjects in a randomised, double-blind, crossover design. Single and multiple dose effects were monitored using a battery of tests comprising critical flicker fusion threshold (CFFT), choice reaction time (CRT), simulated car tracking, and subjective ratings of perceived sedation (LARS) and of sleep behaviour (LSEQ). Compared with placebo baseline scores, treatment with lorazepam 2 mg (both single and multiple doses) resulted in a widespread impairment of CRT, tracking accuracy, and CFFT. Single doses of alprazolam 0.5 mg reduced CFFT with respect to the placebo baseline. Single and multiple dose treatment with both drugs resulted in subjective reports of sedation, a reduction of sleep onset latency, and improved sleep quality. Only lorazepam 2 mg significantly disrupted the integrity of behaviour on waking from sleep. These results suggest important pharmacodynamic differences between the two drugs in the doses used.