Structure-property relationship in polyethylene composite

The development of high performance cheetah skin structure for the first time and its use as a filler for polyethylene composite. The huge improvement in mechanical and physical performance of the composite make it a material of choice for different applications

Synthesis and characterization of silver/montmorillonite/chitosan bionanocomposites by chemical reduction method and their antibacterial activity

Silver nanoparticles (AgNPs) of a small size were successfully synthesized using the wet chemical reduction method into the lamellar space layer of montmorillonite/chitosan (MMT/Cts) as an organomodified mineral solid support in the absence of any heat treatment. AgNO3, MMT, Cts, and NaBH4 were used as the silver precursor, the solid support, the natural polymeric stabilizer, and the chemical reduction agent, respectively. MMT was suspended in aqueous AgNO3/Cts solution. The interlamellar space limits were changed (d-spacing = 1.24–1.54 nm); therefore, AgNPs formed on the interlayer and external surface of MMT/Cts with d-average = 6.28–9.84 nm diameter. Characterizations were done using different methods, ie, ultraviolet-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray fluorescence spectrometry, and Fourier transform infrared spectroscopy. Silver/montmorillonite/chitosan bionanocomposite (Ag/MMT/Cts BNC) systems were examined. The antibacterial activity of AgNPs in MMT/Cts was investigated against Gram-positive bacteria, ie, Staphylococcus aureus and methicillin-resistant S. aureus and Gram-negative bacteria, ie, Escherichia coli, E. coli O157:H7, and Pseudomonas aeruginosa by the disc diffusion method using Mueller Hinton agar at different sizes of AgNPs. All of the synthesized Ag/MMT/Cts BNCs were found to have high antibacterial activity. These results show that Ag/MMT/Cts BNCs can be useful in different biological research and biomedical applications, including surgical devices and drug delivery vehicles

Antifungal properties of phenyl fatty hydroxamic acids and their copper complexes synthesized based on canola and palm kernel oils

Phenyl fatty hydroxamic acids (PFHAs) were synthesized by phenyl hydroxylaminolysis of canola or palm kernel oils using lipozyme TL IM as catalyst. Copper complexes of phenyl fatty hydroxamic acids (copper phenyl fatty hydroxamate (Cu-PFHs)) acids were prepared by stirring the phenyl fatty hydroxamic acids which were dissolved in hexane and copper(II) nitrate solution. The antifungal properties of phenyl fatty hydroxamic acids and its copper(II) complex Cu-PFHs based on canola and palm kernel oils were separately investigated against Candida parapsilosis, Candida albicans and Aspergillus fumigatus by the disc diffusion method using Mueller-Hinton agar. The results showed that antifungal activity of Cu-PFHs is higher than phenyl fatty hydroxamic acids do and also the activity of phenyl fatty hydroxamic acids and Cu-PFHs increase while their concentrations increase. The antifungal activity of phenyl fatty hydroxamic acids and Cu-PFHs are significantly higher than nystatin while use against the A. fumigatus, C. parapsilosis and C. albicans and also are significantly higher than ketoconazole while use against the A. fumigatus

3D Bioprinting for Tissue and Organ Fabrication

The field of regenerative medicine has progressed tremendously over the past few decades in its ability to fabricate functional tissue substitutes. Conventional approaches based on scaffolding and microengineering are limited in their capacity of producing tissue constructs with precise biomimetic properties. Three-dimensional (3D) bioprinting technology, on the other hand, promises to bridge the divergence between artificially engineered tissue constructs and native tissues. In a sense, 3D bioprinting offers unprecedented versatility to co-deliver cells and biomaterials with precise control over their compositions, spatial distributions, and architectural accuracy, therefore achieving detailed or even personalized recapitulation of the fine shape, structure, and architecture of target tissues and organs. Here we briefly describe recent progresses of 3D bioprinting technology and associated bioinks suitable for the printing process. We then focus on the applications of this technology in fabrication of biomimetic constructs of several representative tissues and organs, including blood vessel, heart, liver, and cartilage. We finally conclude with future challenges in 3D bioprinting as well as potential solutions for further development.United States. Office of Naval Research. Young Investigator ProgramNational Institutes of Health (U.S.) (Grants EB012597, AR057837, DE021468, HL099073 and R56AI105024)Presidential Early Career Award for Scientists and Engineer

Sleep paralysis in medieval Persia – the Hidayat of Akhawayni (?–983 AD)

Among the first three manuscripts written in Persian, Akhawayni’s Hidayat al-muta’allemin fi al-tibb was the most significant work compiled in the 10th century. Along with the hundreds of chapters on hygiene, anatomy, physiology, symptoms and treatments of the diseases of various organs, there is a chapter on sleep paralysis (night-mare) prior to description and treatment of epilepsy. The present article is a review of the Akhawayni’s teachings on sleep paralysis and of descriptions and treatments of sleep paralysis by the Greek, medieval, and Renaissance scholars. Akhawayni’s descriptions along with other early writings provide insight into sleep paralysis during the Middle Ages in general and in Persia in particular

Synthesis and characterization of Zeolite/Fe3O4 nanocomposite by green quick precipitation method.

A green quick precipitation method was successfully used for synthesis of magnetic iron oxide nanoparticles (Fe3O4-NPs) on the surface of sodium/potassium type zeolite. Ferric chloride, ferrous chloride and sodium hydroxide aqueous solutions were used in the synthesis and coating of the Fe3O4-NPs on the surface of the zeolite to produce the zeolite/magnetic iron oxide nanocomposite (zeolite/Fe3O4 –NCs). The reaction was performed in aqueous suspension phase under the ambient condition as green chemistry method. Characterization with Fourier transforms infrared spectroscopy (FT‒IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDXF) and transmission electron microscopy (TEM) confirmed the formation of Fe3O4-NPs with mean particle sizes of 3.55±1.02 nm on the surface of the zeolite

Fabrication of cellulose nanocrystals as potential anticancer drug delivery systems for colorectal cancer treatment

Polysaccharide nanocrystals have great potential to be used as improved drug carriers due to their low cost, high biodegradability, and biocompatibility. This study reports the synthesis of cellulose nanocrystals (CNC) loaded with 5-fluorouracil (CNC/5FU) to evaluate their anticancer activity against colorectal cancer cells. X-ray and Fourier-transform infrared spectroscopy demonstrated that acid hydrolysis successfully degraded the amorphous cellulose to liberate the crystal regions. From transmission electron microscopy, CNC/5FU appeared as rod-like nanocrystals with an average length and width of 69.53 ± 1.14 nm and 8.13 ± 0.72 nm, respectively. The anticancer drug 5FU showed improved thermal stability after being loading onto CNC. From UV–vis spectroscopy data, the drug encapsulation efficiency in CNC/5FU was estimated to be 83.50 ± 1.52%. The drug release of CNC/5FU was higher at pH 7.4 compared to those at pH 4.2 and 1.2. From the cytotoxicity assays, CNC did not affect the viability of CCD112 colon normal cells. On the other hand, CNC/5FU exhibited anticancer effects against HCT116 and HT-29 colorectal cancer cells. The anticancer actions of CNC/5FU against HCT116 cells were then confirmed using an in vitro tumor-on-chip model and clonogenic assay. Mechanistic studies demonstrated that CNC/5FU killed the cancer cells by mainly inducing cell apoptosis and mitochondrial membrane damage. Overall, this study indicated that CNC/5FU could be a potential nanoformulation for improved drug delivery and colorectal cancer treatment

Artificial Neural Network Modeling for Predicting of some Ion Concentrations in the Karaj River

The water quality of the Karaj River was studied through collecting 2137 experimental data set gained by 20 sampling stations. The data included different parameters such as T (temperature), pH, NTU (turbidity), hardness, TDS (total dissolved solids), EC (electrical conductivity) and basic anion, cation concentrations. In this study a multi-layer perceptron artificial neural network model was designed to predict the calcium, sodium, chloride and sulfate ion concentrations of the Karaj River. 1495 data set were used for training, 321 data set were used for test and 321 data set were used for validation. The optimum model holds sigmoid tangent transfer function in the middle layer and three different forms of the training function. The root mean square error (RMSE), mean relative error (MRE) and regression coefficient (R) between experimental data and model’s outputs were measured for training, validation and testing data sets. The results indicate that the ANN model was successfully applied for prediction of calcium ion concentration

Delirium Associated with Donepezil in a Patient with Alzheimer’s Disease: a Case Report

Donepezil, a member of the acetylcholinesterase inhibitor family, is approved for management of cognitive impairments as well as behavioral complications in patients with neurodegenerative Alzheimer's disease. Generally, donepezil is regarded as a safe medication in patients with Alzheimer’s disease although there have been reports of several minor adverse events including gastrointestinal disturbances. Herein we describe a patient with Alzheimer’s disease who demonstrated delirious behavior upon treatment with donepezil