Hybrid thermosensitive hydrogel/amniotic membrane structure incorporating S-nitrosothiol microparticles: potential uses for controlled nitric oxide delivery.

Insufficient levels of nitric oxide may lead to chronic and acute wounds. Additionally, it is crucial that nitric oxide is prepared in a controlled-release manner due to its gaseous nature and short half-life. To address this issue, utilizing nitric oxide donors, particularly S-nitrosothiols such as S-nitrosoglutathione (GSNO), could efficiently overcome instability and aid in biomedical applications.

Osteogenic potential of adipose stem cells on hydroxyapatite-functionalized decellularized amniotic membrane.

Amniotic membrane (AM) is an attractive source for bone tissue engineering because of its low immunogenicity, contains biomolecules and proteins, and osteogenic differentiation properties. Hydroxyapatite is widely used as bone scaffolds due to its biocompatibility and bioactivity properties. The aim of this study is to design and fabricate scaffold based on hydroxyapatite-coated decellularized amniotic membrane (DAM-HA) for bone tissue engineering purpose.

Fabrication of a tailor-made conductive polyaniline/ascorbic acid-coated nanofibrous mat as a conductive and antioxidant cell-free cardiac patch.

Polyaniline (PANI) waspolymerized on nanofibrous polycaprolactone mats as cell-free antioxidant cardiac patches (CPs), providing electrical conductivity and antioxidant properties. The fabricated CPs took advantage of intrinsic and additive antioxidant properties in the presence of PANI backbone and ascorbic acid as a biocompatible dopant of PANI. The antioxidant nature of CPs may reduce the serious repercussions of oxidative stress, produced during the ischemia-reperfusion (I/R) process following myocardial infarction.

EMEMI: An interference-free mini-incubator with integrated electric and magnetic field exposure for real-time microscopic imaging of field effects.

Uninterrupted microscopic observation and real-time imaging of cell behavior during exposure to the stimulus, for example, electric and/or magnetic fields, especially for periods of several days, has been a challenge in experimental bioelectromagnetics due to a lack of proper gas/temperature conditions outside the incubator. Conventional mini-incubators might suffer from stray fields produced by heating elements. We report an in vitro electric and magnetic fields (EMF) exposure system embedded inside a novel under-the-microscope mini-CO -incubator with a unique design to avoid electromagnetic interference from the heating and circulation functions while ensuring the requisite temperature.

High-efficient serum-free differentiation of trabecular meshwork mesenchymal stem cells into Schwann-like cells on polylactide electrospun nanofibrous scaffolds.

Cell-based therapies of the peripheral nerve injury (PNI) have provided satisfactory outcomes among which Schwann cells (SCs) are the most reliable candidate to improve repair of the damaged nerve, however, it is difficult to obtain sufficient amount of SCs for clinical applications. Trabecular meshwork-derived mesenchymal stem cells (TM-MSCs) are newly introduced neural crest originated MSCs, which may have a desirable potential for Schwann-like differentiation due to their common lineage. On the other hand, one of the challenges of cell-based therapies is usage of serum containing media which is inappropriate for clinical applications.

Enhanced neural differentiation by applying electrical stimulation utilizing conductive and antioxidant alginate-polypyrrole/poly-l-lysine hydrogels.

The challenge of restoration from neurodegenerative disorder requires effective solutions. To enhance the healing efficiencies, scaffolds with antioxidant activities, electroconductivity, and versatile features to encourage neuronal differentiation are potentially useful. Herein, polypyrrole-alginate (Alg-PPy) copolymer was used to design antioxidant and electroconductive hydrogels through the chemical oxidation radical polymerization method.

Size-adjustable self-assembled nanoparticles through microfluidic platform promotes neuronal differentiation of mouse embryonic stem cells.

Neuronal differentiation from stem cells is one of the most potent therapeutic approaches for recovering neurological function in individuals with neurodegenerative disorders. Herein, an on-demand intracellular retinoic acid released nanoparticles with tunable size and accurately controlled physico-biological properties have been prepared for achieving efficient neuronal differentiation. The amphiphilic chitosan oligosaccharide-cholesterol copolymers were synthesized by varying cholesterol content and self-assembled into spherical micelle in a microfluidic chip with different flow rates.

A hybrid oxygen-generating wound dressing based on chitosan thermosensitive hydrogel and decellularized amniotic membrane.

Amniotic membrane (AM) has been utilized as a wound dressing extensively. Given the importance of oxygen in wound healing, here we have reported the fabrication and characterization of an oxygen-generating wound dressing based on AM. This construct was composed of HO-loaded polylactic acid (PLA) microparticles embedded within a chitosan/β-glycerophosphate (β-GP) thermosensitive hydrogel covered with a layer of decellularized human-AM.

Enhanced mechanical properties and electrical conductivity of Chitosan/Polyvinyl Alcohol electrospun nanofibers by incorporation of graphene nanoplatelets.

The subject of this paper is to develop a highly conductive Graphene nanoplatelets (GNPs)-Chitosan (CS)/Polyvinyl Alcohol (PVA) (GNPs-CP) nanofibers with excellent mechanical properties. An experimental study was designed to produce nanofibers based on CP nanofibers as matrix and GNPs as reinforcement materials. The microstructure and the surface morphology of the electrospun nanofibers along with their electrical and mechanical properties were examined to study the effect of GNPs content.

Enhancing Cellular Infiltration on Fluffy Polyaniline-Based Electrospun Nanofibers.

Despite the unique properties of polyaniline (PANI), the processability of this smart polymer is associated with challenges. Particularly, it is very difficult to prepare PANI nanofibers due to poor solubility, high charge density, and rigid backbone. The most common approach for solving this problem is blending PANI with a carrier polymer.

A Review on Modifications of Amniotic Membrane for Biomedical Applications.

The amniotic membrane (AM) is the innermost layer of the fetal placenta, which surrounds and protects the fetus. Its unique structure, in addition to its physical and biological properties, makes it a useful substance in many applications related to regenerative medicine. The use of this fantastic substance with a century-old history has produced remarkable results , , and even in clinical studies.

Microfluidic fabrication of alendronate-loaded chitosan nanoparticles for enhanced osteogenic differentiation of stem cells.

Aims: In this study, we used a cross-junction microfluidic device for preparation of alendronate-loaded chitosan nanoparticles with desired characteristics to introduce a suitable element for bone tissue engineering scaffolds.

Main Methods: By controlling the reaction condition in microfluidic device, six types of alendronate-loaded chitosan nanoparticles were fabricated which had different physical properties. Hydrodynamic diameter of synthetized particles was evaluated by dynamic light scattering (102 to 215 nm).

Nanofibrous Scaffolds Containing Hydroxyapatite and Microfluidic-Prepared Polyamidoamin/BMP-2 Plasmid Dendriplexes for Bone Tissue Engineering Applications.

Objective: The aim of this study is to fabricate functional scaffolds to gene delivery bone morphogenetic protein-2 (BMP-2) plasmid for bone formation in bone tissue engineering.

Methods: Dendriplexes (DPs) of generation 4 polyamidoamin (G4-PAMAM)/BMP-2 plasmid were prepared through microfluidic (MF) platform. The physiochemical properties and toxicity of DPs were evaluated by DLS, AFM, FESEM and MTT assay.

Surface mineralized hybrid nanofibrous scaffolds based on poly(l-lactide) and alginate enhances osteogenic differentiation of stem cells.

Surface mineralized nanofibrous scaffolds hold great potential for bone tissue engineering applications. In this study, a new hybrid nanofibrous scaffold composed of alginate/poly(l-lactide) nanofibers was fabricated using electrospinning method and then crosslinking process was employed. Hydroxyapatite crystal formation took place using in situ precipitation by immersion of the scaffolds in simulated body fluid solution for 10 days at 37°C.

L. inermis-loaded nanofibrous scaffolds for wound dressing applications.

Since ancient times, some herbal medicines have been extensively used for burn and wound treatments, showing preference to the common synthetic medications by virtue of having less side effects and faster healing rate. In this study, hybrid nanofibrous scaffolds of poly-l-lactic-acid (PLLA) and gelatin incorporated L. inermis were fabricated via electrospinning technique.

The synergistic effect of nano-hydroxyapatite and dexamethasone in the fibrous delivery system of gelatin and poly(l-lactide) on the osteogenesis of mesenchymal stem cells.

Recently, electrospun nanofibrous scaffolds are vastly taken into consideration in the bone tissue engineering due to mimicking the natural structure of native tissue. In our study, surface features of nanofibers were modified through simultaneous electrospining of the synthetic and natural polymers using poly l-lactide (PLLA) and gelatin to fabricate the hybrid scaffold (PLLA/gelatin). Then, hydroxyapatite nanoparticles (nHA) were loaded in electrospun PLLA nanofibers (PLLA,nHA/gelatin) and also dexamethasone (DEX) was incorporated in these fibers (PLLA,nHA,DEX/gelatin) in the second experiment.

Polymer/metal nanocomposites for biomedical applications.

Polymer/metal nanocomposites consisting of polymer as matrix and metal nanoparticles as nanofiller commonly show several attractive advantages such as electrical, mechanical and optical characteristics. Accordingly, many scientific and industrial communities have focused on polymer/metal nanocomposites in order to develop some new products or substitute the available materials. In the current paper, characteristics and applications of polymer/metal nanocomposites for biomedical applications are extensively explained in several categories including strong and stable materials, conductive devices, sensors and biomedical products.

Structural stability and sustained release of protein from a multilayer nanofiber/nanoparticle composite.

The cellular microenvironment can be engineered through the utilization of various nano-patterns and matrix-loaded bioactive molecules. In this study, a multilayer system of electrospun scaffold containing chitosan nanoparticles was introduced to overcome the common problems of instability and burst release of proteins from nanofibrous scaffolds. Bovine serum albumin (BSA)-loaded chitosan nanoparticles was fabricated based on ionic gelation interaction between chitosan and sodium tripolyphosphate.

PLGA/gelatin hybrid nanofibrous scaffolds encapsulating EGF for skin regeneration.

The novel strategies of skin regenerative treatment are aimed at the development of biologically responsive scaffolds capable of delivering multiple bioactive agents and cells to the target tissues. In this study, nanofibers of poly(lactic-co-glycolic acid) (PLGA) and gelatin were electrospun and the effect of parameters viz polymer concentration, acid concentration, flow rate and voltage on the morphology of the fibers were investigated. PLGA nanofibers encapsulating epidermal growth factor were also prepared through emulsion electrospinning.

A home-brew real-time PCR assay for reliable detection and quantification of mature miR-122.

miR-122 is a liver-specific miRNA that has significant gene expression alterations in response to specific pathophysiological circumstances of liver such as drug-induced liver injury, hepatocellular carcinoma, and hepatitis B and C virus infections. Therefore, accurate and precise quantification of miR-122 is very important for clinical diagnostics. However, because of the lack of in vitro diagnostics assays for miR-122 detection and quantification of the existence of an open-source assay could inevitably provide external evaluation by other researchers and the chance of promoting the assay when required.

Ion-exchange polymer nanofibers for enhanced osteogenic differentiation of stem cells and ectopic bone formation.

Nanofibrous scaffolds with specific modifications have shown promising potential for bone tissue engineering applications. In the present study, poly(ether sulfone) (PES) and sulfonated PES (SPES) nanofibers were fabricated via electrospinning. Calcium ions were then incorporated in SPES by immersion in a Ca(OH)2 solution.

Combination of poly L-lactic acid nanofiber scaffold with omentum graft for bone healing in experimental defect in tibia of rabbits.

Purpose: To investigate the osteoconductive properties and biological performance of Poly L-lactic acid (PLLA) with omentum in bone defects.

Methods: PLLA nanofiber scaffolds were prepared via electrospinning technique. Forty four New Zealand white female rabbits randomly divided into three groups of 18 rabbits each.

Cellular infiltration on nanofibrous scaffolds using a modified electrospinning technique.

Electrospinning is currently used to fabricate nanofibrous scaffolds for tissue engineering applications. The major problem of these scaffolds is their intrinsically two-dimensional nature which inhibits cellular migration and in-growth. In this study, we have introduced a modified setup of electrospinning to produce three-dimensional nanofibrous scaffolds which allows improved infiltration of cells.

Neural differentiation of mouse embryonic stem cells on conductive nanofiber scaffolds.

Nerve tissue engineering requires suitable precursor cells as well as the necessary biochemical and physical cues to guide neurite extension and tissue development. An ideal scaffold for neural regeneration would be both fibrous and electrically conductive. We have contrasted the growth and neural differentiation of mouse embryonic stem cells on three different aligned nanofiber scaffolds composed of poly L: -lactic acid supplemented with either single- or multi-walled carbon-nanotubes.