Materials design and characterization of injectable and degradable oxidized alginate PANI:PSS hydrogels for photothermal therapy.

Photothermal therapy has gained great attention as an alternative candidate for radiation therapy or chemotherapy for cancers. However, photothermal agents for photothermal therapy are generally in the form of nanoparticles that are too small to remain in the target tissue, and therefore, the agents are rather quickly removed from the targeted site. Furthermore, conventional photothermal agents are generally expensive or complicated to synthesize.

A chitosan/alginate coated nano-liposome to improve intestinal absorption of curcumin for oral administration.

Attempts to improve low absorption and rapid metabolic conversion of curcumin were made by developing curcumin-loaded bilayer nanoliposomes coated with chitosan and alginate for intestinal-specific drug delivery. A curcumin-loaded nano-liposome was prepared with optimized formulations with phosphatidylcholine, curcumin, chitosan, and alginate. The particle size of the optimized formulation was approximately 400 nm, and the encapsulation efficiency was more than 99%.

Aluminum Hydroxide Nano- and Microstructures Fabricated Using Scanning Probe Lithography with KOH Ink.

Using scanning probe lithography (SPL) with KOH ink, this study fabricates aluminum hydroxide (Al(OH)) nano- and microfeatures on a gold (Au) film that has been deposited on an aluminum (Al) layer. Hydroxyl ions (OH) from the KOH ink loaded onto the Au film can react with the underlying Al layer to form Al(OH) structures due to the decrease in the pH of the reacting solution. In this process, Al(OH) solidification is governed by the pH of the KOH ink solution, which is affected by its volume.

Effects of a graphene oxide-alginate sheet scaffold on rotator cuff tendon healing in a rat model.

Background: Natural polymer scaffolds used to promote rotator cuff healing have limitations in terms of their mechanical and biochemical properties. This animal study aimed to investigate the effects of combined graphene oxide (GO) and alginate scaffold and the toxicity of GO on rotator cuff healing in a rat model.

Methods: First, the mechanical properties of a GO/alginate scaffold and a pure alginate scaffold were compared.

Increased interleukin-6 and TP53 levels in rotator cuff tendon repair patients with hypercholesterolemia.

Background: A previous study reported that hyperlipidemia increases the incidence of tears in the rotator cuff tendon and affects healing after repair. The aim of our study was to compare the gene and protein expression of torn rotator cuff tendons in patients both with and without hypercholesterolemia.

Methods: Thirty patients who provided rotator cuff tendon samples were classified into either a non-hypercholesterolemia group (n=19, serum total cholesterol [TC] <200 mg/dL) and hypercholesterolemia group (n=11, serum TC ≥240 mg/dL) based on their concentrations of serum TC.

Comparison of the Characteristics of Rotator Cuff Tissue in a Diabetic Rat Model.

This study evaluated the biomechanical and histologic characteristics of the rotator cuff tendon and muscle tissue with rat models with diabetes mellitus (DM) (group 1) and 30 male rats without DM (group 2). We conducted a time zero study without any additional procedures or external variables at 9 weeks after induction of the diabetic rat model. Thereafter, quantitative evaluation of advanced glycation end products (AGEs) was accomplished via enzyme-linked immunosorbent assay and immunohistochemistry (IHC).

Effect of a Porous Suture Containing Transforming Growth Factor Beta 1 on Healing After Rotator Cuff Repair in a Rat Model.

Background: The healing failure rate after rotator cuff repair is considerably high.

Purpose: To evaluate the effect of a porous suture containing transforming growth factor beta 1 (TGF-β1) on the sustained release of TGF-β1 and rotator cuff healing in a rat model.

Study Design: Controlled laboratory study.

Electrically Conducting Pullulan-Based Nanobiocomposites Using Carbon Nanotubes and TEMPO Cellulose Nanofibril.

Hybrid nanobiocomposite films are prepared using a solution casting by incorporating TEMPO cellulose nanofibrils (TOCNs) and carbon nanotubes (CNTs) into an aqueous solution of pullulan (PULL). The presence of CNT is confirmed by XRD characterization, and the prepared film shows an increased degree of crystallinity after the addition of TOCNs and CNT. The maximum degree of crystallinity value is obtained for CNT 0.

Is a Local Administration of Parathyroid Hormone Effective to Tendon-to-Bone Healing in a Rat Rotator Cuff Repair Model?

To evaluate the effect of local parathyroid hormone (PTH) administration on rotator cuff tendon-to-bone healing in a rat model compared with systemic PTH injection and untreated controls. PTH-alginate scaffold was prepared and sustained release of PTH was confirmed. Bilateral supraspinatus tendon repairs were performed in 39 rats (group 1, supraspinatus repair only; group 2, supraspinatus repair with systemic PTH injection; group 3, supraspinatus repair with local PTH administration via an absorbable scaffold; n = 13 each).

Fabrication of diffraction gratings by top-down and bottom-up approaches based on scanning probe lithography.

Generation of diffraction gratings by top-down and bottom-up approaches based on scanning probe lithography is demonstrated. With regard to top-down fabrication, silicon nanostructured diffraction gratings are fabricated through one-dimensional (1D) dip-pen-nanolithography (DPN). Nanodot arrays (two-dimensional simple cubic lattice) of alkanethiol self-assembled monolayers (SAMs) are printed by 1D DPN on an Au-film-coated silicon substrate with lattice distances of 700, 1000, and 1200 nm.

Mechanical Augmentation With Absorbable Alginate Sheet Enhances Healing of the Rotator Cuff.

For anatomical restoration of a repaired rotator cuff, mechanical augmentation of the repaired structure is essential. Using histological and biomechanical evaluation in a rat model, the authors sought to determine the efficacy of an absorbable alginate sheet at the supraspinatus tendon-to-bone repair site for healing of the rotator cuff tear. Forty adult (12 weeks old) male Sprague- Dawley wild-type rats were used in this study.

Synthesis of Iron Oxide/Gold Composite Nanoparticles Using Polyethyleneimine as a Polymeric Active Stabilizer for Development of a Dual Imaging Probe.

The combination of magnetic and plasmonic properties using iron oxide/gold nanocomposite particles is crucial for the development of multimodal molecular imaging probes. In this study, iron oxide/gold composite nanoparticles (NanoIOGs) were synthesized via the on-site reduction of an Au precursor salt by polyethyleneimine (PEI) molecules attached to iron oxide nanoparticles (IONPs), and they were employed in magnetic resonance and dark-field microscope imaging. PEI is considered as a polymeric active stabilizer (PAS), acting as a reducing agent for the synthesis of Au and a dispersant for nanoparticles.

Sustained Delivery of Transforming Growth Factor β1 by Use of Absorbable Alginate Scaffold Enhances Rotator Cuff Healing in a Rabbit Model.

Background: The failure rate for healing after rotator cuff repair is relatively high.

Purpose: To establish a system for sustained release of transforming growth factor β1 (TGF-β1) using an alginate scaffold and evaluate the effects of the sustained release of TGF-β1 on rotator cuff healing in a rabbit model.

Study Design: Controlled laboratory study.

Preparation of new natural silk non-woven fabrics by using adhesion characteristics of sericin and their characterization.

Electro-spun regenerated silk webs have been extensively studied for biomedical applications because of the simplicity of their fabrication methods However, the productivity of the electro-spinning process is low for web fabrication and the mechanical properties of the electro-spun silk web are not satisfactory, which restricts its commercialization. In this study, a new silk non-woven fabric was successfully fabricated by wetting and hot press treatments using the excellent binding characteristic of sericin. The effects of the press temperature and residual sericin content on the preparation, structure, and properties of the silk non-woven fabric were examined.

Antioxidative and antiinflammatory activities of quercetin-loaded silica nanoparticles.

Utilizing the biological activities of compounds by encapsulating natural components in stable nanoparticles is an important strategy for a variety of biomedical and healthcare applications. In this study, quercetin-loaded silica nanoparticles were synthesized using an oil-in-water microemulsion method, which is a suitable system for producing functional nanoparticles of controlled size and shape. The resulting quercetin-loaded silica nanoparticles were spherical, highly monodispersed, and stable in an aqueous system.

Polyethyleneimine-mediated synthesis of superparamagnetic iron oxide nanoparticles with enhanced sensitivity in T2 magnetic resonance imaging.

The development of iron oxide nanoparticles (IONPs) with enhanced r2 relaxivity is important for achieving greater sensitivity in in vivo magnetic resonance (MR) imaging. In this study, it was considered that polyethyleneimine (PEI) could play a role in varying the particle and cluster sizes in IONP synthesis, leading to different r2 relaxivities. To demonstrate this, superparamagnetic IONPs were synthesised in the presence of NH4OH and PEI using a co-precipitation method.

Alginate-based composite sponge containing silver nanoparticles synthesized in situ.

Silver-based biomaterials have been developed in a variety of bactericidal applications, especially for wound dressings. In this study, silver nanoparticles (AgNPs) were synthesized in a sodium alginate solution and then the composite sponge containing AgNPs was prepared from the nanocolloid solution. The alginate-stabilized AgNPs had the mean negative zeta potential of -52.

Biologic filler using human fibroblasts and placenta extracts.

Soft tissue augmentation with injectable materials has been a challenging problem for plastic and reconstructive surgeons. Although filler materials have been used for soft tissue augmentation, adverse effects such as inflammation, distortion, and repeated procedures due to absorption still exist. In this study, biologic filler containing human fibroblasts and placenta extracts was developed to overcome these problems as a concept of cell therapy.

Antimicrobial polyethyleneimine-silver nanoparticles in a stable colloidal dispersion.

Excellent colloidal stability and antimicrobial activity are important parameters for silver nanoparticles (AgNPs) in a range of biomedical applications. In this study, polyethyleneimine (PEI)-capped silver nanoparticles (PEI-AgNPs) were synthesized in the presence of sodium borohydride (NaBH(4)) and PEI at room temperature. The PEI-AgNPs had a positive zeta potential of approximately +49 mV, and formed a stable nanocolloid against agglomeration due to electrostatic repulsion.

Different effects of PLGA and chitosan scaffolds on human cartilage tissue engineering.

Clinical application of the cartilage formed by tissue engineering is not practical due to the failure to maintain long-term tissue structural integrity. One of the important factors for maintaining integrity is the biomaterial for a scaffold. The purpose of the current study was to evaluate the difference between poly-lactic glycolic acid (PLGA) and chitosan as scaffolds.

Tissue-engineered bone formation with gene transfer and mesenchymal stem cells in a minimally invasive technique.

Background: The objective of this study was to use a chitosan-alginate gel to implant bone marrow-derived mesenchymal stem cells subcutaneously in a minimally invasive manner and promote bone formation by the simultaneously transferred osteogenic protein (OP)-1 (bone morphogenic protein-7) gene.

Method And Results: The complex of polyethylenimine/luciferase plasmid DNA embedded in the gel was able to transfect HEK 293 cells on a culture dish or co-encapsulated in the gel. When injected into the subcutaneous space of mice, luciferase expression was two to three orders of magnitude increased above the background.

Nasal augmentation using injectable alginate and mesenchymal stem cells in the rabbit.

Background: The goal of this study was to evaluate the use of the autogenous mesenchymal stem cells (MSCs) impregnated in an injectable alginate gel containing platelet-rich plasma (PRP) for nasal augmentation in rabbit model.

Methods: Bone marrow-derived MSCs were isolated and expanded from New Zealand white rabbits. At confluence, the cells were mixed with sodium alginate solution.