Chondroitin sulfate immobilized PCL nanofibers enhance chondrogenic differentiation of mesenchymal stem cells.

Cold Atmospheric Plasma (CAP) is used as a promising method in surface modification for immobilization of chondroitin sulfate functional biomacromolecules on PCL nanofibrous substrates for cartilage tissue engineering. The GAG-grafted scaffolds are able to successfully support the attachment and proliferation of mesenchymal stem cells (MSCs). The seeded scaffolds show the chondro-differentiation of MSCs during a 21-days cell culture in a non-differential medium.

Ionic liquid tethered PEG-based polyurethane-siloxane membranes for efficient CO/CH separation.

This study introduces a new polyethylene glycol (PEG) based polyurethane-siloxane membrane containing a quaternary ammonium ionic liquid for CO/CH separation. The designed ionic liquid was prepared in two steps: (i) (3-chloropropyl)triethoxysilane (CPS) and N,N-dimethylpropyl amine (NDPA) were reacted with each other to form the methoxysilane-functionalized quaternary ammonium component, then (ii) chloride ion (Cl) of the product was exchanged with tetrafluoroborate ion (BF). The resulting compound, a reactive methoxysilane-functionalized ionic liquid (Si-IL) was chemically anchored to the polymer backbone through the sol-gel hydrolysis and condensation reaction.

Atorvastatin loaded PLGA microspheres: Preparation, HAp coating, drug release and effect on osteogenic differentiation of ADMSCs.

Polymer/bioceramic composite micro-particles have been used for bone regeneration in order to address weak mechanical properties/bioactivity of polymers and to enable easy filling of irregular bone defects through minimally invasive injection procedure. The purpose of this study was to determine whether injectable apatite-coated atorvastatin (AT) loaded Poly (d,l-lactide-co-glycolide) (PLGA) micro-particles can support osteogenic differentiation of adipose derived mesenchymal stem cells(ADMSCs). Particle preparation conditions (oil-in-water (O/W) emulsion), were carefully adjusted to yield uniform particles of about 20-50 µm in diameter.

Antimicrobial wound dressings with high mechanical conformability prepared through thiol-yne click photopolymerization reaction.

Radical mediated photochemical thiol-yne click polymerization of thiol-terminated polyurethane prepolymers, with poly(ethylene glycol) soft segment at two different molecular weights, a propargyl terminated urethane crosslinker and silver salt was utilized to prepare versatile wound dressings containing well-dispersed Ag° nanoparticles produced via in situ reduction of Ag ions. The dressings with optimized chemical structure showed desirable fluid handling capacity (up to 4.84 g/10 cm d) to provide moist environment over damaged tissue.

Impact of Gold Nanoparticles on Amyloid β-Induced Alzheimer's Disease in a Rat Animal Model: Involvement of STIM Proteins.

Alzheimer's disease (AD) is the most common type of neurodegenerative amyloid disorder causing progressive cognitive decline and memory loss. A considerable number of therapies for AD rely on inhibition/delay/dissociation of amyloid beta (Aβ) oligomers and fibrils. In this case, nanoparticles (NPs) demonstrated substantial effects on the Aβ fibrillation process; however, their effects on progressive cognitive decline and memory have been poorly investigated in vivo.

Tough, hybrid chondroitin sulfate nanofibers as a promising scaffold for skin tissue engineering.

Fabrication of gelatin/polyvinyl alcohol/chondroitin sulfate (GEL/PVA/CS) hybrid nanofibrous scaffolds using acetic acid and water as an environmentally friendly solvent system via electrospinning for skin tissue engineering was investigated. Modeling and optimization of the nanofibers were performed using response surface methodology (RSM). The influence of CS ratio on mechanical, physical and biological properties of the nanofibers was studied.

Cold atmospheric plasma as a promising approach for gelatin immobilization on poly(ε-caprolactone) electrospun scaffolds.

Poly(Ɛ-caprolactone) (PCL) is a biocompatible polymer with a high potential to be used in tissue engineering especially in tight tissues. In the current study, cold atmospheric plasma (CAP) is used as a promising method for immobilization of gelatin as a functional biomacromolecule on PCL nanofibrous substrates. The CAP surface modification leads to oxidation of chemical groups existing on the PCL surface without doing any damage to the bulk properties of biomaterials for gelatin biomacromolecule grafting.

Green and non-leaching anti-bacterial and cytocompatible coating with build-in quaternary ammonium salt derived from methoxysilane functionalized soybean oil.

Preparation and evaluation of non-leaching antimicrobial polymeric coatings, derived from soybean oil, against bacterial contamination of some metallic biomedical devices are described in this work. Cyclic carbonate derivative of soybean oil (CSBO) was subjected to the reaction with 3-aminopropyl trimethoxysilane to produce a methoxysilane functional soybean oil (Si-SBU) with urethane linkage. A quaternary ammonium salt containing fatty amide molecule with reactive siloxane moiety (Si-SBQ) was also synthesized from soybean oil.

Silyl diol ester as a new selectivity control agent in MgCl-supported Ziegler-Natta systems for propylene polymerization: catalyst structure and polymer properties.

In this study, bis(benzoyloxy)dimethylsilane (SDE) was developed as a non-phthalate selectivity control agent (internal donor (ID) and external donor (ED)) in MgCl-supported Ziegler-Natta (ZN) systems. The impact of SDE as an ID was investigated in regards to chemical composition, morphology, adsorption behavior (using FTIR spectroscopy, WAXD and SEM studies) and the propylene polymerization performance of the catalyst. The results of the adsorption behavior of SDE revealed that SDE, while able to stabilize the electronically unsaturated surfaces of MgCl [(104) and (110)], has a rather high tendency to be absorbed on strongly acidic Mg ions at the corners of these crystals.

A green dispersive liquid phase microextraction technique based on the solidification of switchable hydrophilic fatty acid for determination of polynuclear aromatic hydrocarbons in aqueous samples.

A green dispersive liquid phase microextraction approach based on the solidification of switchable hydrophilic fatty acid as an extraction phase has been developed for the determination of 16 priority polynuclear aromatic hydrocarbons (PAHs) in aqueous samples. In this study, the centrifugation step was omitted by the applying salting-out phenomenon. The influence of main variables on the efficiency of the procedure was studied by chemometric methods.

Chitosan-based biocompatible dressing for treatment of recalcitrant lesions of cutaneous leishmaniasis: A pilot clinical study.

Background: Chitosan has a biocompatible, biodegradable and nontoxic nature. The effectiveness of nano-chitosan films in the treatment of cutaneous leishmaniasis has been confirmed previously in susceptible laboratory animals.

Aims: The aim of this study is to evaluate the safety and efficacy of a chitosan-based biocompatible dressing in patients with cutaneous leishmaniasis who were either nonresponsive to or had medical contraindications for conventional treatments.

Graphene oxide containing chitosan scaffolds for cartilage tissue engineering.

Enhancement of physical and mechanical properties of the scaffolds is achieved via various methods including cross-linking and incorporation of nano particles. In the present research chitosan-based scaffolds firstly were reinforced with the incorporation of the graphene oxide (GO) nanoparticles. The GO nanoparticles were synthesized from graphite successfully and were identified by TGA, XRD, SEM and FTIR analytical methods.

Effect of rinsing time and surface contamination on the bond strength of silorane-based and dimethacrylate-based composites to enamel.

Background: The aim of this study was to assess whether saliva contamination and rinsing time for 15, 30, and 60 seconds, affects the shear bond strength of silorane and methacrylate-based composites to enamel.

Material And Methods: Two light cure resin, P60 (3M ESPE) and Filtek LS Silorane were tested. 120 sound premolars were randomly divided into four groups of 30 teeth based on composite type with or without saliva contamination after etching and rinsing.

Design and optimization of process parameters of polyvinyl (alcohol)/chitosan/nano zinc oxide hydrogels as wound healing materials.

Composite hydrogels as wound dressings feature healing properties in treating wounds. In this study, polyvinyl (alcohol)/chitosan/nano zinc oxide nanocomposite hydrogels were formed using the freeze-thaw method and essential process parameters including thawing time, thawing temperature, and the number of freeze-thaw cycles was investigated to model nanocomposites employing response surface methodology. Critical properties including water vapor transmission rate, porosity, wound fluid absorption, and gel content were modeled using process parameters.

A Review on the Catalytic Acetalization of Bio-renewable Glycerol to Fuel Additives.

The last 20 years have seen an unprecedented breakthrough in the biodiesel industry worldwide leads to abundance of glycerol. Therefore, the economic utilization of glycerol to various value-added chemicals is vital for the sustainability of the biodiesel industry. One of the promising processes is acetalization of glycerol to acetals and ketals for applications as fuel additives.

Polyurethane-Polycaprolactone Blend Patches: Scaffold Characterization and Cardiomyoblast Adhesion, Proliferation, and Function.

A remarkable challenge in myocardial tissue engineering is the development of biomimetic constructs that can potentially improve myocardial repair and regeneration. Polyurethane (PU) scaffolds are extensively utilized in the cardiovascular system. We have synthesized a new biodegradable poly(ester-ether urethane urea) (PEEUU) using a new and simple method.

Development of a simvastatin loaded injectable porous scaffold in situ formed by phase inversion method for bone tissue regeneration.

Introduction:: The use of injectable scaffolds as a minimally invasive method is a good choice in tissue engineering applications. A critical parameter for the tissue engineering scaffolds is a suitable morphology with interconnected pores. We present the development of a simvastatin loaded scaffold that forms in situ and provides the porous structure with interconnected pores.

Enhanced chondrogenic differentiation of bone marrow mesenchymal stem cells on gelatin/glycosaminoglycan electrospun nanofibers with different amount of glycosaminoglycan.

Tissue engineering is a new technique to help damaged cartilage treatment using cells and scaffolds. In this study we tried to evaluate electrospun scaffolds composed of gelatin/glycosaminoglycan (G/GAG) blend nanofibers in chondrogenesis of bone marrow-derived mesenchymal stem cells (BMMSCs). Scaffolds were fabricated by electrospinning technique with different concentration of glycosaminoglycan (0%, 5%, 10%, and 15%) in gelatin matrix.

Preparation and Characterization of Composite Blends Based on Polylactic Acid/Polycaprolactone and Silk.

Silk-reinforced polylactic acid/poly ε-caprolactone composites containing 1-7 wt % of silk fibers were fabricated through the melt-mixing method. The composites were then characterized by implementing Fourier transform infrared (FTIR), differential scanning calorimetry (DSC) and rheometry to investigate functional groups, thermal properties, rheological properties, and intrinsic viscosities of each composite. The crystallinity of the composites was found to decrease upon addition of silk, while, both storage modulus ( G') and loss modulus ( G″) were increased which is an indication of interface bonding between the polymer and silk.

Polyurethane synthesis for vascular application.

Three polyurethane formulations were prepared on the basis of siloxane; two formulations contained 1% and 3% of a hydroxyl functionalized polyhedral oligomeric silsesquioxane [POSS (ROH)] nano-particles (as a co-chain extender) and one was without nano-particle. Structures of the polyurethanes were characterized by FTIR and SEM. The effect of POSS nano-particles on properties of the synthesized PUs was examined for vascular applications by tensile test, contact angle, SEM, AFM and endothelial cells viability evaluation.

PMMA/double-modified organoclay nanocomposites as fillers for denture base materials with improved mechanical properties.

The aim of this study was to investigate the effect of double-modified organoclay on mechanical properties of polymethylmethacrylate (PMMA) denture base resins. An organoclay was further modified via a silanization process using 3-trimethoxysilylpropyl methacrylate (MPS) as a reactive silane coupling agent. X-ray diffraction patterns (XRD), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of MPS in the resulting double-modified nanoclay structure.

Wound dressing based on electrospun PVA/chitosan/starch nanofibrous mats: Fabrication, antibacterial and cytocompatibility evaluation and in vitro healing assay.

Electrospun nanofibrous mats based on biopolymers have been widely investigated for tissue engineering in recent years, primarily due to remarkable morphological similarity to the natural extracellular matrix (ECM). In this research, electrospun PVA/Chitosan/Starch nanofibrous mats were fabricated using electrospinning method for wound dressing application. The prepared nanofibrous mats were then cross-linked to enhanced the water resistance and also optimize the biodegradation rate followed by characterization and evaluation of their properties as wound dressings.

Theranostic Platforms Proposed for Cancerous Stem Cells: A Review.

It is next-to-impossible not to accept that cancer takes a position as the main cause of the global burden of disease, for it is hard to ignore the outnumbered people dying from cancer. Looking at the statistics proves that progress in cancer therapy is always beyond cancer in a race of pessimism about the future; for various kinds of cancers yearly cause death in the world, whereas the conventional and even modern therapies often exhibit lack of reliability in the treatment of cancer. In principle, various reasons are identified for cancer resistance and recurrence.

Effect of organic/inorganic nanoparticles on performance of polyurethane nanocomposites for potential wound dressing applications.

This study focuses on the evaluation and modification of polyurethane (PU) membranes containing organic and inorganic nanoparticles for potential use as a wound dressing. For the purpose of PU nanocomposite preparation, chitosan (CS) was converted into nanoparticles by the ionic-gelation method to improve its blending capability with the PU matrix. These CS nanoparticles (nano-CS) were obtained as a hydrophilic organic filler with different contents and were utilized along with inorganic titanium dioxide (TiO) nanoparticles in the nanocomposite membrane preparation.