纳米多孔二氧化硅作为药物载体的研究进展

目的介绍几种纳米多孔二氧化硅作为药物载体的应用及最新发展动态。方法以国内外有代表性的文献资料31篇为依据,对介孔二氧化硅、二氧化硅气凝胶、微粉硅胶等几种多孔二氧化硅药物载体的结构特性、应用及发展动态进行分析、整理和归纳。结果纳米多孔二氧化硅作为药物载体,借助于其纳米孔道结构、形貌或孔道的控制及表面功能化修饰,可以实现药物的速释、缓释及pH或温度敏感释放。结论纳米多孔二氧化硅作为药物载体具有广阔的应用前景。     

难溶性药物渗透泵制剂制备工艺的研究进展

目的:综述难溶性药物渗透泵制剂制备工艺的研究进展。方法:查阅2003-01-01至2013-04-30国内外涉及难溶性药物渗透泵制剂制备的相关文献,从增加药物溶解度、增强机械穿透系数、增大渗透压差3个方面总结了制备工艺的研究进展。结果与结论:增加药物溶解度可以通过加入β-环糊精、酸碱性物质、制备泡腾渗透泵片等方式实现;增强机械穿透系数可通过采用不对称膜、制备微孔渗透泵等方式实现;增大渗透压差可通过制备单层高分子、双层、三层渗透泵片或者双室渗透泵片来实现。随着新辅料和新技术的应用,难溶性药物特别是治疗指数低、半衰期短的药物制备成渗透泵制剂的工艺将不断创新。     

激光技术促进药物的经皮渗透

目的:综述激光技术促进药物经皮渗透的研究进展。方法:查阅国内外相关文献,对经皮渗透研究中应用的激光类型、激光技术促进药物经皮渗透的机制、影响因素和应用进行综述。结果:激光技术可通过光机械波作用、角质层切除作用使角质层中形成暂时性的连续通道,有助于药物透过。激光类型、激光诱导的光机械波特性、激光参数、药物性质、激光与其他方法的合用对激光促进药物经皮渗透有影响。结论:激光技术可显著促进药物、尤其是亲水性大分子的经皮渗透,具有广阔的应用前景。     

浅谈药物静滴速度与疗效

在各种疾病的治疗过程中,静脉输液是一种应用较为普遍方法。在应用静脉输液进行体液补充和药物滴注时,涉及治疗效果的因素很多,其中,药物静滴速度与疗效。关系尤为密切。 一般来说,输液速度应根据病人情况、药物性质和输液总量等因素来确定。比如,心肺疾患、年老体弱等,速度宜慢;总输液量要求大、心肺功能良好,速度可快     

纳米药物研究进展及前景展望

纳米药物与普通制剂的药物相比,具有较大的表面积、较强的化学活性、较快的吸收速度,在通过生物体的各种屏障、控制药物的释放速度、设定药物的靶向性等许多方面,纳米药物都具有一般药物不可替代的优越性,为药物研究提供了全新的领域。本文从纳米药物的制备、特点、应用等几方面介绍纳米药物的研究进展并展望了纳米药物的前景。     

多孔微球在医药领域的应用

多孔微球作为一种药物新剂型,在药物新制剂的研发以及新剂型的改造方面应用广泛。多孔微球材料来源丰富,如天然高分子材料,无机材料,合成大分子聚合物等。作为一种新型缓/控释给药载体,微球具有保护药物免遭破坏、与某些细胞组织有特殊的亲和性、控制药物释放速度、延长药物作用时间、减少药物不良反应及降低用药量等优点,还可用于特定组织和器官的药物靶向释放等。由于多孔微球具有巨大的比表面积和孔体积,药物可吸附在多孔微球的表面或进入孔道内部,根据机体需要被做成速释或缓释制剂而发挥药效。该文综述了几种典型的多孔微球材料研究概况及其在生物医药领域中的应用,并对其发展前景进行展望。     

药物在输注管道中的损失

<正> 输注药物是临床常用的给药方法,但药物在输注管道中的损失往往被人所疏忽,尤其像硝酸甘油、硝酸异山梨醇等这类用于重症危急病人的药物,要求投药量精确,而药物在输注管道中的损失又直接影响药物的投药量。为了提高临床合理用药水平,本文就其损失的机理、影响因素以及减少损失的方法予以简述。     

促进药物透皮吸收的方法及应用前景

介绍透皮给药制剂的研究进展及促进药物透皮渗透的方法。通过促进药物的透皮吸收，可减少药物的某些首过作用和增加用药顺应性。促进药物透皮渗透的方法主要有添加促透剂、物理方法、制成脂质体及环糊精等。透皮吸收制剂经皮给药，可达到全身治疗的目的，服药顺应性好，患者特别是儿童乐于接受。     

超声波介导的药物转运系统

目的了解超声波介导的药物靶向转运的研究情况。方法通过查阅和分析近年来国外超声波介导的药物转运文献。结果在超声波的作用下,药物能在体内特定部位释放药物,提高药物的局部浓度,以及治疗基因在细胞内的表达,亦增加药物的经皮渗透量。结论超声波具有良好的促进药物经皮吸收和靶向转运作用,具有一定的研究和应用前景。     

超声波介导的药物转运系统

目的 了解超声波介导的药物靶向转运的研究情况。方法 通过查阅和分析近年来国外超声波介导的药物转运文献。结果 在超声波的作用下,药物能在体内特定部位释放药物,提高药物的局部浓度,以及治疗基因在细胞内的表达,亦增加药物的经皮渗透量。结论 超声波具有良好的促进药物经皮吸收和靶向转运作用,具有一定的研究和应用前景。     

An In-vitro Evaluation of Silicone Elastomer Latex for Topical Drug Delivery

A silicone elastomer latex was evaluated as a topical drug-delivery system. With the addition of a fumed silica and the removal of water, the latex produced elastomeric solid films. The water vapour permeability of the solid film was found to be a function of the film composition. An increase in silica content and the incorporation of a water-soluble component, PEG 3350, rendered the silicone elastomer-free film even more permeable to water vapour. The release of hydrocortisone from the elastomer film can be described by a matrix-diffusion-controlled mechanism. Drug diffusion is thought to occur through the hydrophobic silicone polymer network and the hydrated hydrophilic silica region in the film matrix. Silicone elastomer film with a higher silica content exhibited a faster drug-release rate. The addition of PEG 3350 to the film further enhanced the drug-release rate.     

Drug release kinetics from polymeric films containing propranolol hydrochloride for transdermal use

Polymeric films containing propranolol hydrochloride (PPN) were formulated and evaluated with a view to select a suitable formulation for the development of transdermal drug delivery systems. Films containing different ratios of ethyl cellulose (EC), poly(vinylpyrrolidone) (PVP), and PPN were prepared by mercury substrate method. In vitro drug release and skin permeation studies were conducted using paddle over disk and modified Franz diffusion cell, respectively. The drug release profiles from the polymeric film indicated that the drug content in the film decreased at an apparent first-order rate, whereas the quantity of drug release was proportional to the square root of time. The release rate of PPN increased linearly with increasing drug concentration and PVP fraction in the film, but was found to be independent of film thickness. The increase in release rate may be due to leaching of hydrophilic fraction of the film former, which resulted in the formation of pores. It was also observed that the release of drug from the films followed the diffusion-controlled model at low drug concentration. A burst effect was observed initially, however, at high drug loading level, which may be due to rapid dissolution of the surface drug followed by the diffusion of the drug through the polymer network in the film. The in vitro skin permeation profiles displayed increased flux values with increase of initial drug concentration in the film, and also with the PVP content. From this study, it is concluded that the films composed of EC/PVP/PPN, 9:1:3, 8:2:2, and 8:2:3, should be selected for the development of transdermal drug delivery systems using a suitable adhesive layer and backing membrane for potential therapeutic applications.     

Drug metabolism in diabetic subjects with fatty livers

The effect of fatty degeneration of liver parenchyma on drug metabolism was investigated in 21 obese non-insulin-dependent diabetic subjects by measuring plasma antipyrine kinetics, hepatic cytochrome P-450, liver size and the extent of fatty infiltration. The hepatic drug metabolising capacity, as measured by total antipyrine clearance and the estimated total amount of cytochrome P-450, was at the same level as in non-diabetic control subjects with normal livers. Relative antipyrine clearance (per unit weight of liver) and cytochrome P-450 concentrations were significantly lower in the diabetics than in controls. The extent of fatty infiltration correlated poorly with the indices of drug metabolism. In non-insulin-dependent diabetics, slight to moderate hepatic fatty infiltration, without more serious structural distortion interfering with hepatic blood flow or hepatocellular function, seems to have only a minor influence on drug metabolism.     

法莫替丁定时释放小丸的释药机制

目的研究法莫替丁定时释放小丸的释药机制,初步探索有机酸诱导型给药系统的释药机制。方法从离子交换反应、水化作用等方面分别研究了琥珀酸离子和琥珀酸分子在药物释放过程中的作用。结果琥珀酸酸根离子通过与膜材进行离子交换反应造成了新的离子环境,琥珀酸分子由于进入膜材的疏水部分而提高了膜的柔韧性。上述两种作用均可导致膜水化作用增强,从而使膜的透过性明显增加。结论定时释放小丸的时滞是由于膜材的疏水性所致;当水进入丸芯溶解有机酸后,产生的酸根离子及有机酸分子以不同的方式与膜材发生相互作用,显著提高了其透过性,从而使药物快速释放出来。     

柔性脂质体在经皮给药系统中的研究进展

目的 采用响应面法优化北豆根脂肪油的提取工艺，分析其成分组成，并研究北豆根脂肪油的体外抗氧化活性。方法 以北豆根脂肪油提取率为指标，在单因素试验基础上，采用响应面法考察提取温度、提取时间、料液比对提取工艺的影响；采用气相色谱-质谱联用法 (GC-MS) 分析脂肪油的组成；运用清除1,1-二苯基-2-三硝基苯肼（DPPH）自由基实验，评价北豆根脂肪油的体外抗氧化活性。结果 经响应面优化，确定最佳提取工艺为提取温度温度90 ℃，回流提取3次，每次2.3 h，料液比为1:21。在这些条件下，提取率为1.820 %；采用GC-MS从北豆根脂肪油中鉴定出32 个成分；北豆根脂肪油总抗氧化活性随着浓度的增加而逐渐升高，在浓度达到0.833 mg/mL后对DPPH自由基清除率的增幅变缓，当浓度为1.333mg/mL时，清除率为70.1%。结论 优化的工艺方便、稳定、可行，可为后续研究提供依据，北豆根脂肪油中含有多种重要脂肪油成分, 并具有一定的体外抗氧化能力。     

Design and Development of Mixed Film of Pectin: Ethyl Cellulose for Colon Specific Drug Delivery of Sennosides and Triphala

The present study was aimed at developing colon specific drug delivery system for sennosides and Triphala. These drugs are reputed Ayurvedic medicines for constipation in India. The proposed device explored the application of pectin and ethyl cellulose as a mixed film for colon specific delivery. This mixed film was prepared using non-aqueous solvents like acetone and isopropyl alcohol. A 32 factorial design was adopted to optimize the formulation variables like, ratio of ethyl cellulose to pectin (X1) and coat weight (X2). The rate and extent of drug release were found to be related to the thickness and the ratio of pectin to ethyl cellulose within the film. Statistical treatments to the drug release data revealed that the X1 variable was more important than X2. Under simulated colonic conditions, drug release was more pronounced from coating formulations containing higher proportions of pectin. The surface of the device was coated with Eudragit S100 to ensure that the device was more pH dependent and trigger the drug release only at higher pH. The final product is expected to have the advantage of being biodegradable and pH dependant. This type of a film effectively releases the drug while maintaining its integrity.     

整合素α_5β_1与CD_(44)V_3在胃癌中的表达及临床意义

目的本研究旨在探讨整合素α5β1、CD44V3表达水平对胃癌细胞黏附、迁移、髓外浸润过程的影响。方法采用Western blot检测法及RT-PCR分别测量HTB-103、CRL-5822、CRL-5971及CRL-5973等不同对数生长期的胃癌细胞株整合素α5β1、CD44V3蛋白表达水平及整合素α5β1 m RNA、CD44V3 m RNA水平.将不同胃癌细胞株随机分为实验组及对照组,实验组加入整合素α5β1、CD44V3抗体,对照组加入同型Ig G,观察两组胃癌细胞与ECV304细胞系的黏附率、细胞迁移率及胃癌细胞穿过人工基质膜的浸润能力。结果CRL-5822、CRL-5971及CRL-5973细胞整合素α5β1 m RNA相对表达量明显高于HTB-103细胞(P<0.05)。观察组CRL-5822、CRL-5971及CRL-5973细胞株黏附率、迁移率、及浸润率显著低于对照组(P<0.05),而两组HTB-103细胞无统计学差异(P>0.05)。结论整合素α5β1、CD44可能参与胃癌细胞的形成、聚集、生长及浸润的过程,其表达水平与胃癌病程进展具有密切的关系。     

Influence of Plasticizer Level on the Drug Release from Sustained Release Film Coated and Hot-Melt Extruded Dosage Forms

In the current study, the influence of plasticizer level on drug release was investigated for solid dosage forms prepared by hot-melt extrusion and film coating. The properties of two highly water-soluble compounds, diltiazem hydrochloride (DTZ) and chlorpheniramine maleate (CPM), and a poorly water-soluble drug, indomethacin (IDM), were investigated in the melt extrudates containing either Eudragit® RSPO or Eudragit® RD 100 and triethyl citrate (TEC) as the plasticizer. In addition, pellets containing DTZ were film coated with Eudragit® RS 30D and varying levels of TEC using a fluidized bed coating unit. Differential scanning calorimetry (DSC) demonstrated that both CPM and IDM exhibited a plasticization effect on the acrylic polymers, whereas no plasticizing effect by DTZ on Eudragit® RSPO was observed. Thermogravimetric analysis (TGA) was used to investigate the thermal stability of the DTZ, Eudragit® RSPO and TEC at 140 °C, the maximum temperature used in the hot-melt extrusion process. The chemical stability of DTZ and IDM in the extrudate following hot-melt processing was determined by high pressure liquid chromatography (HPLC). Drug release rates of both DTZ and CPM from hot-melt extrudates increased with an increase in the TEC level in the formulations, while the release rate of DTZ from the Eudragit® RS 30D–coated pellets decreased with an increase in TEC in the coating dispersion. This phenomenon was due to the formation of a reservoir polymeric structure as a result of the thermal stress and shear stress involved in the hot-melt extrusion process regardless of the TEC level. In contrast, coalescence of the polymer particles in the film coating process was enhanced with higher levels of TEC, as demonstrated by scanning electron microscopy (SEM). The addition of TEC (0% to 8%) in the IDM hot-melt extrudate formulation had no influence on the drug release rate as the drug release rate was controlled by drug diffusion through the inside of the polymeric materials rather than between the polymer particles.     

Drug release from laminated polymeric films prepared from aqueous latexes

Laminated films comprised of a drug-containing reservoir layer and a drug-free, rate-controlling membrane were prepared from aqueous latexes and investigated as an alternative drug delivery system to polymeric films cast from organic solvents. The reservoir layer was prepared by casting and drying the latex [copolymer of poly(ethylacrylate-methylmethacrylate) esters - Eudragit NE 30D (NE 30D)] containing the dissolved drugs (chlorpheniramine maleate, propranolol HCl, or salicylic acid). Monolithic solutions (salicylic acid-NE 30D) or dispersions (chlorpheniramine maleate or propranolol HCl-NE 30D) were formed, depending on the solubility of the drug in the polymer matrix. Zero-order drug release was achieved by laminating a second, drug-free latex film onto the reservoir layer. The rate-controlling membrane was either attached to, or cast directly onto the reservoir. The release rate was independent of loading for the monolithic dispersions, but dependent on loading for the monolithic solution. Release rates were enhanced by the addition of a hydrophilic polymer, hydroxypropyl methylcellulose, to the rate-controlling membrane. An inverse relationship was observed between the release rate and membrane thickness. The rate-controlling membrane, cast from organic polymer solutions, had a denser structure, resulting in slower drug release when compared with latex-cast laminates.     

A Canadian perspective on documentary film: Drug Addict

BackgroundIn 1948 the first National Film Board (NFB) documentary in Canada about illegal drugs, trafficking, and addiction was produced. The documentary is titled Drug Addict, and was directed by Robert Anderson. This paper provides a socio-historical context for the documentary Drug Addict. Viewing the film through the lens of Canadian history gives readers a better context to understand the claims and representations in the film about law enforcement, people who use illegal drugs and treatment.MethodsTo examine Drug Addict, a socio-historical analysis and case study were conducted. This project's qualitative methodological framework is consistent with its critical theoretical perspective, drawing from Stuart Hall's perspectives on visual and textual representation and cultural criminology.ResultsDrug Addict is a significant documentary because it provides insight into early foundational law enforcement discourses and practices about illegal drugs, addiction, and treatment, including obstacles to drug substitution and maintenance programs. It also highlights the emergence of psychiatry as a new knowledge producer in the area of drug treatment. The film also transmits ideas about the criminal nature of addicts and the need for punitive criminal justice control.ConclusionDrug Addict captures some past and contemporary tensions related to Canadian drug policy. The film also provides another lens to understand some of the foundational frameworks of Canadian drug policy such as the dominance of criminal justice, and its practices of knowledge production, the resistance espoused by institutions to diverse models of treatment such as drug maintenance programs, and the power of visual representation.