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131.
Zahra Bakhtiary Jaleh Barar Ayuob Aghanejad Amir Ata Saei Elhameh Nemati 《Drug development and industrial pharmacy》2017,43(8):1244-1253
Non-small cell lung cancer (NSCLC) patients with sensitizing mutations in the exons 18–21 of the epithelial growth factor receptor (EGFR) gene show increased kinase activity of EGFR. Hence, tyrosine kinase inhibitors (TKIs) such as erlotinib (ETB) have commonly been used as the second line therapeutic option for the treatment of metastatic NSCLC. While the ETB is available as an oral dosage form, the local delivery of this TKI to the diseased cells of the lung may ameliorate its therapeutic impacts. In the current study, we report on the development of ETB-loaded solid lipid nanoparticle (SLN) based formulation of dry powder inhaler (ETB-SLN DPI). ETB-SLNs were formulated using designated amount of compritol/poloxamer 407. The engineered ETB-SLNs showed sub-100?nm spherical shape with an encapsulation efficiency of 78.21%. MTT assay and DAPI staining revealed that the ETB-SLNs enhanced the cytotoxicity of cargo drug molecules in the human alveolar adenocarcinoma epithelial A549 cells as a model for NSCLC. To attain the ETB-SLN DPI, the ETB-SLNs were efficiently spray dried into microparticles (1–5?μm) along with mannitol. The ETB-SLN DPI powder displayed suitable flowability and aerodynamic traits. The Carr's Index, Hausner ratio and Next Generation Impactor (NGI) analyses confirmed deep inhalation pattern of the formulation. Based on these findings, we propose the ETB-SLN DPI as a promising treatment modality for the NSCLC patients. 相似文献
132.
Mehdi Abdollahi Masoud Rezaei Gholamali Farzi 《International Journal of Food Science & Technology》2014,49(3):811-818
A combination of chitosan biopolymer, nanoclay and rosemary essential oil was prepared as a functional bionanocomposite (FBN). Its ability to improve the shelf life of refrigerated (4 ± 1 °C) silver carp fillets was studied. The fresh fillets were left untreated as a control or coated with chitosan, chitosan/clay bionanocomposite and chitosan/clay/rosemary essential oil (Ch/clay/REO) FBN. Then, they were evaluated for chemical, microbial and sensory properties over 16‐day storage. The samples coated with the FBN had the lowest pH and total volatile basic nitrogen. Ch/clay/REO coating efficiently retarded lipid oxidation by decreasing peroxide, free fatty acid and thiobarbituric acid production in the samples. The coating also reduced total viable and psychrotrophic count of the fillets more than 1.5 log by the end of storage. 相似文献
133.
Saffron is the most precious and expensive agricultural product. A dehydration treatment is necessary to convert Crocus sativus L. stigmas into saffron spice. To the best of our knowledge, no information on mass transfer parameters of saffron stigmas is available in the literature. This study aimed at investigating the moisture transfer parameters and quality attributes of saffron stigmas under infrared treatment at different temperatures(60,70, …, 110 °C). It was observed that the dehydration process of the samples occurred in a short accelerating rate period at the start followed by a falling rate period. The effective moisture diffusivity and convective mass transfer coefficient were determined by using the Dincer and Dost model. The diffusivity values varied from1.1103 × 10~(-10)m~2·s~(-1)to 4.1397 × 10~(-10)m~2·s~(-1) and mass transfer coefficient varied in the range of 2.6433 × 10~(-7)–8.7203 × 10~(-7)m·s~(-1). The activation energy was obtained to be 27.86 k J·mol~(-1). The quality assessment results showed that the total crocin content increased, when the temperature increased up to90 °C but, in higher temperatures, the amount of crocin decreased slightly. The total safranal content of the samples decreased slightly when drying temperature increased from 60 °C to 70 °C and then continuously increased up to 110 °C. Also, the amount of picrocrocin increased from 83.1 to 93.3 as the drying temperature increased from 60 °C to 100 °C. 相似文献
134.
Kheirollah Mohammadi Mehdi Ranjbar 《Journal of Materials Science: Materials in Electronics》2017,28(4):3185-3190
This paper reports a novel processing route for producing AgO2/GrO nanocomposites by hydrothermal method. AgO2/GrO nanocomposites as semiconductor materials have been synthesized via a facile one-step process using AgNO3 and glucose as starting reagents. We investigated the influence of the thermal decomposition temperature and reaction time, on the morphology and the particle size of AgO2/GrO nanocomposites. The AgO2/GrO nanocomposites were characterized by FT-IR, UV–Vis spectra, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy. The obtained results exhibited that the synthesized nano product by calcining for 4 h showed excellent uniformity and quality. 相似文献
135.
Mehdi Amoui Mahdi Derakhshanmanesh Jürgen Ebert Ladan Tahvildari 《Journal of Systems and Software》2012,85(12):2720-2737
In this article, we present a generic model-centric approach for realizing fine-grained dynamic adaptation in software systems by managing and interpreting graph-based models of software at runtime. We implemented this approach as the Graph-based Runtime Adaptation Framework (GRAF), which is particularly tailored to facilitate and simplify the process of evolving and adapting current software towards runtime adaptivity. As a proof of concept, we present case study results that show how to achieve runtime adaptivity with GRAF and sketch the framework's capabilities for facilitating the evolution of real-world applications towards self-adaptive software. The case studies also provide some details of the GRAF implementation and examine the usability and performance of the approach. 相似文献
136.
Modeling of non‐disperse solvent extraction of molybdenum(VI) with PC‐88A as extractant and a nanoporous hollow‐fiber membrane contactor as extractor was performed. Computational fluid dynamics was applied for modeling and simulation of molybdenum extraction. Concentration, pressure, and velocity distributions for molybdenum were determined. The extraction of Mo6+ was greatly influenced by the flow rate of feed solution. The extraction efficiency was reduced with higher feed flow rate and increased with the molybdenum content in the feed. The pressure drop along the shell side of the membrane extractor was found to be not significant, being one of the advantages of membrane extractors which assist in reducing the operational costs. The proposed simulation method is capable to prognosticate the performance of solvent extraction of molybdenum in membrane extractors. 相似文献
137.
Polybutadiene/polyhedral oligomeric silsesquioxane nanohybrid: investigation of various reactants in polyesterification reaction 下载免费PDF全文
Seyed Amin Mirmohammadi Mehdi Nekoomanesh‐Haghighi Somayyeh Mohammadian Gezaz Naeimeh Bahri‐Laleh 《Polymer International》2016,65(5):516-525
Nano‐sized polyhedral oligomeric silsesquioxane (POSS) diol or ethylene glycol (EG) as diol monomer was incorporated into hydroxyl‐terminated polybutadiene (HTPBD) chain in the presence of fumaryl or thionyl chloride as extenders. Using these polyesterification reactions, two fumarate‐based polyesters and two polyester sulfites were synthesized. Each couple of polyesters and polyester sulfites includes a linear (diol:EG) and a nanohybrid macromer (diol:POSS). Full structural characterization was performed using Fourier transform infrared, 1H NMR and 13C NMR spectroscopies. Gel permeation chromatography was undertaken to study polyesterification mechanisms by deconvolution of the obtained traces. Finally, differential scanning calorimetry, thermogravimetric analysis and cell culture were performed to evaluate the structure–property relationship for the synthesized macromers in comparison with unreacted HTPBD. © 2016 Society of Chemical Industry 相似文献
138.
Mohammad Mehdi Shahjamali Michel Bosman Shaowen Cao Xiao Huang Xiehong Cao Hua Zhang Stevin Snellius Pramana Can Xue 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(17):2880-2886
Ultrathin triangular gold nanoframes are synthesized in high yield through selective gold deposition on the edges of triangular silver nanoprisms and subsequent silver etching with mild wet etchants. These ultrathin gold nanoframes are surfactant‐free with tailorable ridge thickness from 1.8 to 6 nm and exhibit adjustable and distinct surface plasmon resonance bands in the visible and near‐IR region. In comparison, etching of the nanoprism template by galvanic replacement can only create frame structures with much thicker ridges, which have much lower catalytic activity for 4‐nitrophenol reduction than the ultrathin gold nanoframes. 相似文献
139.
Mojgan Goudarzi Mehdi Mousavi-Kamazani Masoud Salavati-Niasari 《Journal of Materials Science: Materials in Electronics》2017,28(12):8423-8428
In present study, for the first time, ZnO nanoparticles have been synthesized via a simple, novel, solvent and template free solid-state thermal decomposition of the mixed Zn(NO3)·6H2O and cochineal powders as a novel starting reagent at 600?°C for 3 h. The as-prepared product was analyzed by XRD, EDS, SEM, TEM, FT-IR and DRS. Besides, the effect of cochineal powder on the morphology and particle size of ZnO nanoparticles was investigated. The results exhibited that cochineal powder prevents the sintering of nanoparticles and leads to formation of uniform particles. Moreover, the efficiency of ZnO nanoparticles as a photocatalyst for the decolorization of methylene orange (MO) has been evaluated and 90% degradation of MO was obtained after 120 min. 相似文献
140.