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71.
Elahe Sharifisamani Fatemeh Mousazadegan Roohollah Bagherzadeh Masoud Latifi 《Polymer Engineering and Science》2020,60(7):1520-1529
This work presents an interesting method using an electrospinning process to fabricate suture yarns loaded with curcumin to achieve reasonable mechanical properties as well as tunable drug release behavior. Different structures including different yarn counts and twists as well as core-sheath structures were used to adjust drug release properties along with improving the yarn's mechanical properties. The core parts were made of polycaprolactone and the sheath parts were made of polyethylene glycol, polylactic acid, and polycaprolactone. Drugs can be incorporated in both parts based on the required condition and application. Electrospun yarns were compared using both structural properties and their drug release profiles as metrics. The results of comparing drug release profiles of six electrospun yarns with different yarn counts and twists showed that yarns with finer fiber diameters in the core part have more drug release as well as more initial release. Overall evaluations showed that core-sheath drugloaded yarn with appropriate physical and mechanical properties can be a useful material as a drug delivery system to the site of damaged tissue. It can also be concluded that the amount and duration of drug release can be controlled using the structural parameters of electrospun yarns as an engineering tool for designing suture yarns with required properties. 相似文献
72.
Alireza Hosseinzadeh Hassan Namazi 《Polymer-Plastics Technology and Engineering》2020,59(16):1812-1821
ABSTRACT In our work, reversible addition-fragmentation chain transfer (RAFT)/carbon nanotube (CNT)/acrylic acid (AA)/acrylamide (AAm) nanocomposite was synthesized by living radical polymerization. The structure and surface morphology of the synthesized RAFT-CNT-Hydrogel nanocomposites were analyzed by FTIR, 1HNMR, SEM, TEM, XRD, and TGA/DTG techniques. The results indicated that PAA/AAm chains grafted with CNT by RAFT polymerization. RAFT-CNT-Hydrogel nanocomposites for drug release investigated in different buffers resulted in a strong pH-sensitive behavior. In total, the obtained hydrogel drug-delivery systems are presented a proper effect versus stomach cancer in vitro and in vivo, and it can be used as candidates for controlled release of anticancer drugs in stomach with exalted remedial agents. 相似文献
73.
当今社会科技发展快、信息流通量大,人们之间的交流越来越密切,大数据这个高科技时代的产物也应运而生。煤炭作为工业发展的重要组成部分,其发展关系着整个工业的发展。如今,许多现代大型煤矿已能将井下设备信息上传到地面,在地面就可直观的看到设备当前运行的情况,从而更可靠的进行安全生产。通过结合实例将上传的设备信息数据进行整理和分析,从而预测设备的运行状况,提出建设性建议。同时对加强煤矿安全生产、促进煤炭行业现代化建设、提高煤矿的经济效益和社会效益具有重要的意义。 相似文献
74.
为了成功预测竹林山煤矿综放高瓦斯矿井大采高工作面煤层瓦斯涌出量,以主采3号煤层为主要研究对象,针对3号煤层以往开采情况,通过布设测点测量其煤层瓦斯含量和了解相邻矿井瓦斯含量,采用分源预测法、回归法及统计法等预测方法得到了3号煤层瓦斯含量的分布规律,并绘制了3号煤层的瓦斯含量等值线图。对矿井不同生产时期的瓦斯含量进行预测,得到了生产前期、中期及后期采区的最大绝对瓦斯涌出量和最大相对瓦斯涌出量,说明了竹林山煤矿各个时期均属于高瓦斯矿井。 相似文献
75.
Parkinson's disease (PD) is characterized by a progressive loss of dopaminergic neurons and represents a growing health burden to western societies. Like many neurodegenerative disorders the cause is unknown, however, as the pathogenesis becomes ever more elucidated, it is becoming clear that effective delivery is a key issue for new therapeutics. The versatility of today's polymerization techniques allows the synthesis of a wide range of polymer materials which hold great potential to aid in the delivery of small molecules, proteins, genetic material or cells. In this review, we capture the recent advances in polymer based therapeutics of the central nervous system (CNS). We place the advances in historical context and, furthermore, provide future prospects in line with newly discovered advancements in the understanding of PD and other neurodegenerative disorders. This review provides researchers in the field of polymer chemistry and materials science an up-to-date understanding of the requirements placed upon materials designed for use in the CNS aiding the focus of polymer therapeutic design. 相似文献
76.
Emma Groves 《Drug development and industrial pharmacy》2015,41(10):1608-1616
Xanthan gum (XG), a hydrophilic biopolymer with modified release properties, was used to produce directly compressed matrix tablets containing a model drug, sodium p-aminosalicylate. Three formulations were prepared, each containing a different calcium dihydrate salt: calcium chloride, calcium sulfate or dibasic calcium phosphate. The aim of the investigation was to relate the calcium ion content and solubility of the calcium salt to the in vitro drug release profile of the xanthan matrices. Tablet hydration, erosion and drug release were determined in distilled water using the British Pharmacopoeia (BP) paddle method. The data showed that the overall drug release was the greatest with addition of calcium sulfate, followed by calcium chloride and dibasic calcium phosphate. The chloride salt formulation displayed the greatest percentage erosion due to rapid mass loss during the initial phase, followed by those with sulfate or phosphate salts. As xanthan gel viscosity increased and drug release was also found to be lower, it can be concluded that drug release is influenced by the solubility of the salt present in the formulation, since these parameters determine the viscosity and structure of the gel layer. 相似文献
77.
Amphotericin B (AMB) was often used in intra-articular injection administration for fungal arthritis, because it could often bring a satisfactory therapeutic efficacy and a minimum systemic toxic side effect. However, because of the multiple operations and the frequent injections, the compliance of the patients was bad. Therefore, to develop a long-term sustained-released preparation of AMB for mycotic arthritis intra-articular administration is of great significance. The purpose of present study was to develop a long-term sustained-released in situ gel of a water-insoluble drug AMB for mycotic arthritis intra-articular administration. Based on the evaluations of the in vitro properties of the formulations, the formulation containing 10% (w/w) ethanol, 15% (w/w) PG, 0.75% (w/w) HA, 5% (w/w) purified soybean oil, 0.03% (w/w) α-tocopherol, 15% (w/w) water and 55% (w/w) glyceryl monooleate was selected as a suitable intra-articular injectable in situ gel drug delivery system for water-insoluble drug AMB. Furthermore, the results of the in vivo study on rabbits showed that the selected formulation was a safe and effective long-term sustained-released intra-articular injectable AMB preparation. Therefore, the presented in situ AMB gel could reduce the frequency of the administration in the AMB treatment of fungal arthritis, and then would get a good patient compliance. 相似文献
78.
Cationic Nanogels: Reduction‐Sensitive Dextran Nanogels Aimed for Intracellular Delivery of Antigens (Adv. Funct. Mater. 20/2015) 下载免费PDF全文
79.
The spin-transfer nano-oscillator(STNO) has recently acquired a huge amount of research interest, due to its promising easy tunability along with the miniature size. The output frequency control of an STNO through magnetic field and current has been examined almost to its full extent; however, there are issues that still need to be addressed. Here, we propose a novel way of voltage control of the output frequency of an STNO, and alongside reducing its power requirement. 相似文献
80.
Sandeep Kumar Singh Venkatesh Teja Banala Girish K. Gupta Ashwni Verma Rahul Shukla Vivek K. Pawar 《Drug development and industrial pharmacy》2015,41(11):1759-1768
The aim of this study was to fabricate docetaxel loaded nanocapsules (DTX-NCs) with a high payload using Layer-by-Layer (LbL) technique by successive coating with alternate layers of oppositely charged polyelectrolytes. Developed nanocapsules (NCs) were characterized in terms of morphology, particle size distribution, zeta potential (ζ-potential), entrapment efficiency and in vitro release. The morphological characteristics of the NCs were assessed using transmission electron microscopy (TEM) that revealed coating of polyelectrolytes around the surface of particles. The developed NCs successfully attained a submicron particle size while the ζ-potential of optimized NCs alternated between (+) 34.64?±?1.5 mV to (?) 33.25?±?2.1 mV with each coating step. The non-hemolytic potential of the NCs indicated the suitability of the developed formulation for intravenous administration. A comparative study indicated that the cytotoxicity of positively charged NCs (F4) was significant higher (p?0.05) rather than negative charged NCs (F3), plain drug (DTX) and marketed preparation (Taxotere®) when evaluated in vitro on MCF-7 cells. Furthermore, cell uptake studies evidenced a higher uptake of positive NCs (≥1.2 fold) in comparison to negative NCs. In conclusion, formulated NCs are an ideal vehicle for passive targeting of drugs to tumor cells that may result in improved efficacy and reduced toxicity of encapsulated drug moiety. 相似文献