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Seongnam, South Korea

Maeng J.H.,Advanced Therapeutics Research Center | Bang B.W.,Inha University | Lee E.,Advanced Therapeutics Research Center | Kim J.,BioAlpha Inc. | And 4 more authors.
Journal of Materials Science: Materials in Medicine | Year: 2014

The gastrointestinal (GI) endoscopy has become a standard diagnostic tool for GI ulcers and cancer. In this study we studied endoscopic application of epidermal growth factor-containing chitosan hydrogel (EGF-CS gel) for treatment of GI ulcer. We hypothesized that directional ulcer-coating using EGF-CS gel via endoscope would precipitate ulcer-healing. EGF-CS gel was directly introduced to the ulcer-region after ulceration in acetic acid-induced gastric ulcer (AAU) and mucosal resection-induced gastric ulcer (MRU) rabbit and pig models. The ulcer dimensions and mucosal thicknesses were estimated and compared with those in the control group. Healing efficacy was more closely evaluated by microscopic observation of the ulcer after histological assays. In the AAU model, the normalized ulcer size of the gel-treated group was 2.3 times smaller than that in the non-treated control group on day 3 after ulceration (P < 0.01). In the MRU model, the normalized ulcer size of the gel-treated group was 5.4 times smaller compared to that in the non-treated control group on day 1 after ulceration (P < 0.05). Histological analysis supported the ability of EGF-CS gel to heal ulcers. The present study suggests that EGF-CS gel is a promising candidate for treating gastric bleeding and ulcers. © 2013 Springer Science+Business Media New York. Source

Park S.A.,Korea Institute of Machinery and Materials | Lee S.J.,Korea Institute of Machinery and Materials | Lim K.S.,Chonnam National University | Bae I.H.,Chonnam National University | And 4 more authors.
Materials Letters | Year: 2015

In this study, we prepared a helical, biocompatible, and biodegradable stent by 3D rapid prototyping. The fabricated polycaprolactone (PCL) stent was coated with sirolimus mixed with poly-(lactide-co-glycolide) (PLGA), and polyethylene glycol (PEG), via a spraying method for slow drug release. The engineered, drug-eluting, bio-absorbable vascular stent (BVS) was analyzed and tested in vivo, and proving effective in animal experiments. These findings suggest that our new approach is useful for treating coronary thrombosis, and it may provide a promising scaffold for developing biological stent technology. © 2014 Elsevier B.V. All rights reserved. Source

Kim D.W.,Seoul National University | Cho I.-S.,Seoul National University | Kim J.Y.,National Renewable Energy Laboratory | Jang H.L.,Seoul National University | And 6 more authors.
Langmuir | Year: 2010

The noble synthesis method for hydroxyapatite (HAp) nanoparticles was exploited using a fairly simple reaction of Ca(OH)2 and H 3PO4, which does not generate residual harmful anions and consequently does not need an additional washing process. HAp nanoparticles were found to yield from dicalcium phosphate dehydrate (DCPD) as the only intermediate phase, which was monitored by in situ observation study using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), 1H and 31P magic-angle spinning (MAS) NMR. Furthermore, we found that the phase evolution of HAp was preceded by heteronucleation of HAp onto the DCPD surface. The combination of scanning electron microscopy (SEM) and inductively coupled plasma atomic emission spectroscopy (ICP-ES) analysis gave more information on the HAp crystallization process, which was found to be retarded by the residual Ca(OH)2 and slow diffusion process of Ca ions into the interface between HAp and DCPD. These results demonstrate that the synthesis of pure HAp nanoparticles with high throughput can be achieved by controlling the residual Ca(OH)2 and diffusion process of Ca ions. © 2009 American Chemical Society. Source

Park J.-K.,BioAlpha Inc. | Park J.-K.,Sunchon National University | Nah J.-W.,Sunchon National University | Choi C.,Sunchon National University
Polymer (Korea) | Year: 2015

The adhesion of tissue and organ occur with frequency after surgery. Theomosensitive hydrogel was prepared from poloxamer/chitosan/epidermal growth factor as adhesion barrier agent. The prepared hydrogel showed sol-gel transition temperatures around human temperature and gelation temperature was the faster within 1 min. The hydrogel sustained the release of epidermal grow factor during 7 days. The hydrogel was highly effective for the prevention of tissue and organ adhesion in rat model. The thermosensitive and antibacterial chitosan hydrogel can be useful to consider the anti-adhesion barrier with increased adhesion of organ and sustained release of epidermal growth factor. © 2015 The Polymer Society of Korea. All rights reserved. Source

The present invention relates to a carrier for growth factor related to regeneration of bone tissues that is capable of arbitrarily controlling the delivery rate of growth factors related to bone regeneration and thus especially applicable to a bone void filler in the fields of the dental or orthopedic applications. The carrier for controlling the delivery rate of the growth factor in the present invention is composed of a hyaluronic acid hydrogel having a distribution of interconnected pores and a calcium phosphate microsphere being distributed in the pores of the hyaluronic acid hydrogel. The calcium phosphate microsphere having a porosity suitable for delivery of the growth factor is positioned into the pores of the cross-linked hyaluronic acid hydrogel to complete the carrier.

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