微透析技术在抗菌药物药动学和药效学中的应用

微透析技术是一项新兴的体内药物分析技术。通过微透析技术与药动学和药效学模型结合,实现对组织或细胞外游离态药物浓度及其相应药理效应的同时研究,不仅有利于进一步明确药物的剂量-效应关系,制定临床最佳给药方案,而且也为个体化给药提供了科学依据。本文综合近年文献,对微透析技术的基本原理以及在抗菌药物药动学和药效学研究中的应用作一综述。     

皮肤微透析技术在药动学及药效学研究中的应用进展

目的:介绍皮肤微透析技术在药动学及药效学研究中的应用进展。方法:采用文献综述法,阐述国内、外近几年来将皮肤微透析技术应用于药动学及药效学研究的进展。结果与结论:皮肤微透析技术可以在不破坏皮肤组织的条件下对皮肤或皮下组织细胞外液物质浓度进行采样,与其他皮肤药动/药效学采样技术相比具有微创、实时、多位点等优点,可广泛应用于皮肤药动学和药效学研究。皮肤微透析技术在中药药动学及药效学研究中有很好的应用前景。     

脑微透析在药物监测中的应用

脑微透析是一种微创取样技术,具有多位点、实时取样和可在线等优点,在脑部药物监测中越来越受到关注。脑微透析技术为脑部药物浓度的监测提供了一种有效的新途径,可为新药研发与临床合理用药提供科学依据,在脑部给药系统研究中,特别是药动学及药效学研究中优势显著,具有很好的应用前景。本文综述了有关脑部微透析技术的特点及发展,介绍了脑微透析技术在药物监测研究中的进展,分别归纳了微透析技术在实验动物和临床患者中的应用情况。     

微透析在药代动力学研究中的应用

微透析是一较新的组织间隙液采样技术，近几年来在体微透析技术在药代动力学和药效学的研究中被广泛应用，本文描述了微透析采样的原理及其在药代动力学中的应用特点，并对其在人体药代动力学研究中的应用进行了介绍。     

微透析技术在药物代谢和药代动力学研究中的应用

本文介绍了近年来有关微透析技术在药物代谢和药动学研究领域中应用的现状入已取得重大进展。微透析技术除应用于动物模型中的研究外,在人体中的研究特别是临床应用方面亦在发展中,该项技术在药物代谢和药代动力学研究领域中有广阔应用前景,但微透析探针校正和对微透析取样获得的少量样品的分析方法是仍需要深入研究的问题。     

微透析采样技术在抗乳腺癌药物研究方面的应用

目的:介绍微透析采样技术在抗乳腺癌药物方面的研究与应用现状。方法:参阅国内外文献,进行分析、归纳和总结。结果:微透析采样技术在乳腺癌的发病机制、乳腺癌药物临床前和临床药理及药动学、PK-PD结合模型、联合用药合理性等方面研究应用广泛。结论:微透析采样技术结合现代成像技术,在乳腺癌肿瘤局部药动学研究方面具有广阔的应用前景。     

微透析技术在生命科学研究中的应用

简要介绍微透析这种较新的生物采样技术及其基本原理,参考最新文献综述其在生物医学方面的多种应用,指出微透析技术将来在药代动力学、药效学以及疾病诊断控制方面极具价值.     

微透析技术及其在经皮给药系统中的应用

综述了经皮微透析技术及其近年来在经皮给药系统中的应用,包括经皮吸收药物的药动学研究及生物利用度和生物等效性评价。     

基于微透析技术的苦参碱凝胶经皮给药的药动学研究

目的 建立同步测定经皮给药制剂在皮肤、血液中药动学的方法,研究苦参碱凝胶在体内的药动学行为。方法 应用经体外和体内回收率校正建立的基于微透析探针的皮肤血液双位点同步微透析系统,通过在皮肤和颈静脉植入探针,在大鼠腹部脱毛部位给予苦参碱凝胶,连续收集探针中12 h的透析液,并采用LC-MS微量检测技术测定探针透析液中的药物浓度。结果 本研究成功构建了双位点同步微透析药动学评价系统,大鼠皮肤给予苦参碱凝胶后,皮肤中的药物浓度、AUC值、半衰期均显著高于血液中药物浓度。结论 本研究建立的微透析结合LC-MS的取样及检测技术为经皮给药制剂的药动学研究提供了新的技术平台。     

黄连解毒汤“方证对应”的PK-PD研究和数据挖掘技术的应用

目的:基于"方证对应"理论,探讨黄连解毒汤在药动学和药效学方面的研究思路及方法。方法:查阅近年来国内、外学者在黄连解毒汤药动学和药效学方面的研究成果,论述药动-药效学(PK-PD)结合模型和数据挖掘技术在中药复方物质基础研究和药动学研究中的重要性。结果:通过引入PK-PD结合模型和数据挖掘技术,有助于揭示方剂与证候之间的对应关系。结论:在"方证对应"理论的指导下,黄连解毒汤的药动学和药效学研究还需进一步深入。     

微透析技术在靶组织局部药物浓度检测中的应用

微透析技术是一项越来越被广泛使用的在体研究技术,其遵循透析原理,以探针为基础取样,可连续检测局部组织细胞外液的药物浓度,能满足常规的药代动力学/药效学(PK-PD)研究。本文就其在靶组织局部药物浓度检测中的应用作一简要介绍。     

药代-药效学建模分析金黄色葡萄球菌在不同喹诺酮类#br# 抗菌药物浓度下的生长曲线

目的 利用数学模型拟合金黄色葡萄球菌(金葡菌)在不同喹诺酮类药物的最低抑菌浓度(minimum inhibitory concentration, MIC)倍数浓度下的生长曲线,求得关键的药效学参数,为抗菌药物的PK/PD研究提供支持。方法 获得3种喹诺酮类药物-西他沙星、莫西沙星和左氧氟沙星,在不同MIC值下的细菌生长曲线,利用非线性混合效应估计(nonlinear mixed-effect estimation, NLME)数学模型进行了拟合。结果 所建立的模型可以对不同药物MIC值下的生长曲线进行拟合,并可获得主要的药效学参数,包括PK/PD指数、PK/PD靶值。 结论 所选择的数学模型可以用于拟合金葡菌在不同药物浓度下的生长曲线,得到的PK/PD(AUC/MIC)靶值,且与采用其他方法所获得的结果具有可比性。     

Microdialysis in drug discovery

Microdialysis has been developed during the last 25 years by several authors primarily to study brain function and changes in levels of endogenous compounds such as neurotransmitters or metabolites. The development of microdialysis for the purpose of measuring drugs was initiated during the late eighties. This technique provides a means of continuous plasma sampling without repeated blood sampling and the applicability to the study of drug metabolism and pharmacokinetics in experimental animals and human. Also, the microdialysis technique allows the study of plasma protein binding and the saturation of protein binding. The implantation of the microdialysis probe in other tissues and organs, like central nervous system, adipose tissue and heart, allows the study of drug distribution. On the other hand, the measurement of endogenous substances using the microdialysis technique permits the study of the effect of drugs on neurotransmission and metabolism. Moreover, as this technique allows the simultaneous determination of different physiological parameters such as blood pressure, locomotor and convulsive activity, it is a suitable tool for pharmacokinetic-pharmacodynamic studies of drugs and pharmacokinetic-pharmacodynamic (PK-PD) modeling. Lastly, the reverse microdialysis is a powerful technique for the study of local actions of drugs in different tissues such as specific brain nuclei, myocardium, liver or skeletal muscle. So, this article reviewed the vast applications of the microdialysis technique for the study of pharmacokinetic and pharmacodynamic properties of drugs.     

Integration not isolation: arguing the case for quantitative and systems pharmacology in drug discovery and development

Quantitative and systems pharmacology (QSP) is an emerging modelling technique that combines the flexibility of systems biology and tractability of compartmental pharmacokinetic-pharmacodynamic modelling techniques. Historically, there has been extensive use of QSP within the field of pharmacokinetics to optimise drug biopharmaceutical properties. However, application to target and biomarker selection, and design of preclinical and clinical studies is limited, but growing rapidly. In this article we highlight the impact of QSP within drug discovery and development by citing examples from within the field of pharmacology and we argue for a more systematic integration of QSP within the drug discovery and development paradigm.     

Facilitation of drug evaluation in children by population methods and modelling

The pharmacokinetics and pharmacodynamics of drugs are different in adult and paediatric populations, the latter being particularly heterogeneous. These differences in pharmacokinetics and pharmacodynamics justify specific studies but raise a number of ethical and practical issues. The main practical difficulties to circumvent while performing clinical studies in children are the invasiveness of the procedures and the obstacles to patient recruitment. The invasiveness related to pain/anxiety and blood loss precludes the performance of classical pharmacokinetic studies in children in many instances, particularly in neonates and infants. Population approaches, which rely on pharmacokinetic-pharmacodynamic modelling, are particularly appealing in paediatric populations because these models can cope with sparse data. The relevance of population approaches to investigation of the dose-concentration-effect relationships and to qualitative/quantitative assessment of factors that may explain interindividual variability has already been emphasized. The aims of this review are to summarize the currently available literature on population pharmacokinetic-pharmacodynamic studies in children and to discuss a number of recent methodological developments that may facilitate the evaluation of drugs in this population by alleviating invasiveness and, subsequently, facilitating recruitment of patients. The present survey confirms that population approaches in paediatrics have already reached a large audience and that they are mostly used for analysis of sparse data. However, pharmacokinetic-pharmacodynamic studies in children are still scarce. New classes of models may extend the scope of the use of population models in paediatrics. Kinetic-pharmacodynamic models, where use of the term 'kinetic' rather than 'pharmacokinetic' emphasizes the absence of pharmacokinetic data, are indirect models where the (unobserved) drug kinetics are described by a single compartment involving a single rate constant. These models, which alleviate the need for blood samples used for the measurement of drug concentration, may be very useful in paediatric studies. Physiological and physiopathological models also have potential applications but require further development. Because the number of measurements in a single individual needs to be limited in children, it is crucial to optimize the design of the experiment in order to avoid inaccurate and unreliable results. In this review, formal optimization and simulation to evaluate a design are presented, and specific problems raised by the application of these techniques in paediatrics are addressed. Finally, the related technique of clinical trial simulation and its applications are presented and discussed.     

Microdialysis. A novel tool for clinical studies of anti-infective agents

In vivo microdialysis (MD) is an innovative clinical technique that has been employed in preclinical research and metabolic studies in patients for more than a decade. Recently, MD has been adopted for human drug studies and has opened up the opportunity to quantify tissue drug distribution in vivo. The particular advantage of MD for the anti-infective field relates to the fact that MD allows for online measurement of the unbound, pharmacologically active drug fraction in the interstitial space fluid (ISF), the anatomically defined target site for most bacterial infections. The aim of this review is to provide an overview of the current literature about MD in anti-microbial drug studies. It will be shown that MD has become feasible in most human tissues including brain and lung. So far, several MD studies have demonstrated that anti-microbial concentrations at the effect site may be subinhibitory, although effective concentrations are attained in serum, a finding that has significant impact on clinical decision making. In addition to its property as a pharmacokinetic sampling technique, MD offers unique opportunities in pharmacokinetic-pharmacodynamic (PK-PD) research and has the potential to streamline the decision process on proper drug dosing in drug development.     

Pharmacokinetic-pharmacodynamic modelling of the hypothermic and corticosterone effects of the 5-HT1A receptor agonist flesinoxan

The current investigation describes the pharmacokinetic-pharmacodynamic correlation of the hypothermic and the corticosterone effect of flesinoxan in the rat simultaneously. A specific objective was to determine the influence of handling the animal. The pharmacokinetic-pharmacodynamic correlation was determined following intravenous administration of 3 and 10 mg/kg flesinoxan in 5 or 15 min. Serial blood samples were obtained for determination of the time course of the flesinoxan and corticosterone concentrations by high performance liquid chromatography. Body temperature was monitored using a telemetric probe. The pharmacokinetics of flesinoxan were described using a three-compartment model. Both the hypothermic and the corticosterone response were successfully described using a physiological indirect response model. It is shown that customizing the animal prior to the experiment has no influence on the pharmacokinetic-pharmacodynamic parameter estimates. Furthermore, the similarity in potency between the hypothermic and corticosterone effects suggests that both are mediated via tissues with a similar receptor-effector coupling efficiency.     

可分剂量甲磺酸二氢麦角碱缓释微囊片的制备及体外释放机制的研究

目的对可分剂量甲磺酸二氢麦角碱缓释微囊片(EDDTEM)的处方进行研究,并研究其体外释放机制。方法以海藻酸钠-壳聚糖为囊材,采用复凝聚法制备甲磺酸二氢麦角碱缓释微囊(EEM)并压制成片,采用正交设计实验优化处方。结果EEM的最优处方为:海藻酸钠与药物比例为6∶1,海藻酸钠-壳聚糖比例为4∶1,海藻酸钠浓度为2.5%。所制缓释片释药行为符合Higuchi方程,释药机理为扩散和溶蚀并存。结论EDDTEM具有良好的体外缓释效果,可进一步进行体内释药行为考察。     

Target controlled anaesthetic drug dosing

It belongs to the particularities of anaesthesia that the conscious response of the patient to drug therapy is not available for the adjustment of drug therapy and that the side-effects of anaesthetic drug therapy would be in general lethal if no special measures were taken such as artificial ventilation. Both conditions do not allow for a slow, time-consuming titration of drug effect towards the therapeutically effective window, but measures have to be taken to reach a therapeutic target fast (within seconds to a few minutes), reliably, and with precision. Integrated pharmacokinetic-pharmacodynamic models have proved to be a useful mathematical framework to institute such drug delivery to patients. The theory of model-based interactive drug dosing on the basis of common pharmacokinetic-pharmacodynamic (pk-pd) models is outlined and the target-controlled infusion system (TCI) is presented as a new anaesthetic dosing technique that has developed during the last decade. Whereas TCI presents an open-loop dosing strategy (the past output does not influence the future input), current research deals with the model-based adaptive closed-loop administration of anaesthetics. In these systems the past output is used to adapt and individualize the initial pk-pd model to the patients and thus has an influence on future drug dosing which is based on the adapted model.     

Pharmacokinetic/pharmacodynamic modelling in oncological drug development

For many oncological agents, myelosuppression is the dose-limiting toxicity and the quantitative characterisation of the relationship between drug dose, plasma concentration and haematological toxicity is of importance in the drug development. Mechanism-based population pharmacokinetic-pharmacodynamic models have been developed for this purpose and the applications of these in candidate selection, first-in-man studies, prodrug and formulation development, dose finding, schedule optimisation, assessing influence of modifying agents, drug combination studies, subgroup identification and feedback individualisation are reviewed.