Latent stem cell-stimulating radially aligned electrospun nanofibrous patches for chronic tympanic membrane perforation therapy.

Chronic tympanic membrane (TM) perforation is a tubotympanic disease caused by either traumatic injury or inflammation. A recent study demonstrated significant progress in promoting the regeneration of chronic TM perforations through the application of nanofibers with radially aligned nanostructures and controlled release of growth factors. However, radially aligned nanostructures with stem cell-stimulating factors have never been used.

Development of Plum Seed-Derived Carboxymethylcellulose Bioink for 3D Bioprinting.

Three-dimensional bioprinting represents an innovative platform for fabricating intricate, three-dimensional (3D) tissue structures that closely resemble natural tissues. The development of hybrid bioinks is an actionable strategy for integrating desirable characteristics of components. In this study, cellulose recovered from plum seed was processed to synthesize carboxymethyl cellulose (CMC) for 3D bioprinting.

Engineering Considerations on Large-Scale Cultured Meat Production.

In recent decades, cultured meat has received considerable interest as a sustainable alternative to traditional meat products, showing promise for addressing the inherent problems associated with conventional meat production. However, current limitations on the scalability of production and extremely high production costs have prevented their widespread adoption. Therefore, it is important to develop novel engineering strategies to overcome the current limitations in large-scale cultured meat production.

Engineering considerations of iPSC-based personalized medicine.

Personalized medicine aims to provide tailored medical treatment that considers the clinical, genetic, and environmental characteristics of patients. iPSCs have attracted considerable attention in the field of personalized medicine; however, the inherent limitations of iPSCs prevent their widespread use in clinical applications. That is, it would be important to develop notable engineering strategies to overcome the current limitations of iPSCs.

Reduced graphene oxide-incorporated calcium phosphate cements with pulsed electromagnetic fields for bone regeneration.

Natural calcium phosphate cements (CPCs) derived from sintered animal bone have been investigated to treat bone defects, but their low mechanical strength remains a critical limitation. Graphene improves the mechanical properties of scaffolds and promotes higher osteoinduction. To this end, reduced graphene oxide-incorporated natural calcium phosphate cements (RGO-CPCs) are fabricated for reinforcement of CPCs' characteristics.

SHMT1 siRNA-Loaded hyperosmotic nanochains for blood-brain/tumor barrier post-transmigration therapy.

The near-perivascular accumulation in solid tumors and short-lived span in circulation, derails even the most competent nanoparticles (NPs) from achieving their maximum therapeutic potential. Moreover, delivering them across the blood brain/tumor barrier (BBB/BTB) is further challenging to sought anticancer effect. To address these key challenges, we designed a linearly aligned nucleic acid-complexed polydixylitol-based polymeric nanochains (X-NCs), with inherent hyperosmotic properties enabling transmigration of the BBB/BTB and navigation through deeper regions of the brain tumor.

Enhanced Osteogenesis of Dental Pulp Stem Cells In Vitro Induced by Chitosan-PEG-Incorporated Calcium Phosphate Cement.

The use of bone graft materials is required for the treatment of bone defects damaged beyond the critical defect; therefore, injectable calcium phosphate cement (CPC) is actively used after surgery. The application of various polymers to improve injectability, mechanical strength, and biological function of injection-type CPC is encouraged. We previously developed a chitosan-PEG conjugate (CS/PEG) by a sulfur (VI) fluoride exchange reaction, and the resulting chitosan derivative showed high solubility at a neutral pH.

Injectable Thermosensitive Chitosan Solution with -Glycerophosphate as an Optimal Submucosal Fluid Cushion for Endoscopic Submucosal Dissection.

Endoscopic submucosal dissection (ESD) is a surgical procedure to remove early neoplastic lesions in the gastrointestinal tract with the critical issue of perforation. A submucosal fluid cushion, such as normal saline, is used as a cushioning agent to prevent perforation; however, its cushioning maintenance is insufficient for surgery. In this study, we introduce an injectable thermosensitive chitosan solution (CS) with -glycerophosphate (-GP) as a submucosal injection agent for ESD.

Enhanced Osteogenic Differentiation of Periodontal Ligament Stem Cells Using a Graphene Oxide-Coated Poly(ε-caprolactone) Scaffold.

Periodontal diseases occur through bacterial infection in the oral cavity, which can cause alveolar bone loss. Several efforts have been made to reconstruct alveolar bone, such as grafting bone substitutes and 3D-printed scaffolds. Poly(ε-caprolactone) (PCL) is biocompatible and biodegradable, thus demonstrating its potential as a biomaterial substitute; however, it is difficult for cells to adhere to PCL because of its strong hydrophobicity.

Development of novel gene carrier using modified nano hydroxyapatite derived from equine bone for osteogenic differentiation of dental pulp stem cells.

Hydroxyapatite (HA) is a representative substance that induces bone regeneration. Our research team extracted nanohydroxyapatite (EH) from natural resources, especially equine bones, and developed it as a molecular biological tool. Polyethylenimine (PEI) was used to coat the EH to develop a gene carrier.

Sulfur(VI) Fluoride Exchange (SuFEx)-Mediated Synthesis of the Chitosan-PEG Conjugate and Its Supramolecular Hydrogels for Protein Delivery.

Supramolecular hydrogels are considered promising drug carriers in the tissue engineering field due to their versatile nature. Chitosan hydrogels without chemical cross-linkers have low cytotoxicity and good delivery capacity; however, they have lower mechanical properties for injectable hydrogel usage. In this study, we developed novel chitosan derivatives via click chemistry for fabricating supramolecular hydrogels with higher mechanical strength under mild conditions.

3D-Printed Poly(ε-Caprolactone)/Hydroxyapatite Scaffolds Modified with Alkaline Hydrolysis Enhance Osteogenesis In Vitro.

The 3D-printed bioactive ceramic incorporated Poly(ε-caprolactone) (PCL) scaffolds show great promise as synthetic bone graft substitutes. However, 3D-printed scaffolds still lack adequate surface properties for cells to be attached to them. In this study, we modified the surface characteristics of 3D-printed poly(ε-caprolactone)/hydroxyapatite scaffolds using O2 plasma and sodium hydroxide.

Aligned Nanofiber-Guided Bone Regeneration Barrier Incorporated with Equine Bone-Derived Hydroxyapatite for Alveolar Bone Regeneration.

Post-surgery failure of dental implants due to alveolar bone loss is currently critical, disturbing the quality of life of senior dental patients. To overcome this problem, bioceramic or bone graft material is loaded into the defect. However, connective tissue invasion instead of osteogenic tissue limits bone tissue regeneration.

Development and characterization of waste equine bone-derived calcium phosphate cements with human alveolar bone-derived mesenchymal stem cells.

Calcium phosphate cements (CPCs) are regarded as promising graft substitutes for bone tissue engineering. However, their wide use is limited by the high cost associated with the complex synthetic processes involved in their fabrication. Cheaper xenogeneic calcium phosphate (CaP) materials derived from waste animal bone may solve this problem.

Epidermal Growth Factor-Releasing Radially Aligned Electrospun Nanofibrous Patches for the Regeneration of Chronic Tympanic Membrane Perforations.

Chronic tympanic membrane (TM) perforations can cause otorrhea. To date, various types of tissue engineering techniques have been applied for the regeneration of chronic TM perforations. However, the application of nanofibers with radially aligned nanostructures and the simultaneous release of growth factors have never been applied in the regeneration of chronic TM perforations.

JNK2 silencing and caspase-9 activation by hyperosmotic polymer inhibits tumor progression.

c-Jun N-terminal kinase 2 (JNK2) is primarily responsible for the oncogenic transformation of the transcription factor c-Jun. Expression of the proto-oncogene c-Jun progresses the cell cycle from G1 to S phase, but when its expression becomes awry it leads to uncontrolled proliferation and angiogenesis. Delivering a JNK2 siRNA (siJNK2) in tumor tissue was anticipated to reverse the condition with subsequent onset of apoptosis which predominantly requires an efficient delivering system capable of penetrating through the compact tumor mass.

Correction: Development of a bio-electrospray system for cell and non-viral gene delivery.

[This corrects the article DOI: 10.1039/C7RA12477E.].

Development of a bio-electrospray system for cell and non-viral gene delivery.

Bio-electrospray technology is a very attractive tool for preparing scaffolds and depositing desired solutions on various targets by electric force. In this study, we focused on the application of a bio-electrospray (BES) technique to spray cells on the target and to simultaneously deliver genetic constructs into the cells, called non-viral gene delivery-based bio-electrospray (NVG-BES). Using this method, we tried to harvest the electric charge produced during electrospray for the cellular internalization of cationic polymer/DNA nanoparticles as well as the delivery of living cells on the desired substrate.

Effects of pulsing of light on the dentinogenesis of dental pulp stem cells in vitro.

Low power light (LPL) treatment has been widely used in various clinical trials, which has been known to reduce pain and inflammation and to promote wound healing. LPL was also shown to enhance differentiation of stem cells into specific lineages. However, most studies have used high power light in mW order, and there was lack of studies about the effects of very low power light in μW.

Chitosan/PEI patch releasing EGF and the EGFR gene for the regeneration of the tympanic membrane after perforation.

Damage to the eardrum causes acute pain and can lead to chronic otitis media if it develops into chronic tympanic membrane (TM) perforations. Chronic TM perforations are usually treated with surgical methods such as tympanoplasty and myringoplasty. However, these surgeries are not only complicated and difficult but also cost a lot of money.

Directional Matrix Nanotopography with Varied Sizes for Engineering Wound Healing.

Topographic features play a crucial role in the regulation of physiologically relevant cell and tissue functions. Here, an analysis of feature-size-dependent cell-nanoarchitecture interactions is reported using an array of scaffolds in the form of uniformly spaced ridge/groove structures for engineering wound healing. The ridge and groove widths of nanopatterns are varied from 300 to 800 nm and the nanotopography features are classified into three size ranges: dense (300-400 nm), intermediate (500-600 nm), and sparse (700-800 nm).

Enhanced chitosan-DNA interaction by 2-acrylamido-2-methylpropane coupling for an efficient transfection in cancer cells.

Gene therapy is the treatment of human disorders by the introduction of genetic material to specific target cells of a patient. Chitosan and its derivatives show excellent biological properties including biocompatibility, biodegradability and nonallergenicity. Primary amines of chitosan are responsible for its cationic nature and hence binding and protection of DNA for intracellular delivery.