• Korean Journal of Pharmacognosy
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• v.52 no.4
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• pp.228-233
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• 2021

This research was carried out to investigate the moisturizing effects of Agarum cribrosum extract on normal human epidermal keratinocytes (NHEKs). Moisturizing effects of A. cribrosum extract on NHEKs were measured by quantitative realtime RT-PCR to verify the gene expressions related to skin hydration, hyaluronic acid (HA)-ELISA to detect HA production, and cell viability assays. A. cribrosum extract increased the mRNA levels of the AQP3 and HAS2 genes and HA production in NHEKs. On the other hand, A. cribrosum extract decreased the mRNA level of the KRT1 and KRT10 genes known as differentiated keratinocyte marker in NHEKs. This research showed the moisturizing effects of A. cribrosum extract. The results indicate that A. cribrosum extract can be a potent functional ingredient for skin hydration and anti-aging products. Further study is warranted regarding the use of A. cribrosum extract to develop not only cosmetics but also food and medicine.

• Polymer(Korea)
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• v.35 no.3
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• pp.223-227
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• 2011

Stimuli-responsive polymers have been investigated as the materials playing the critical roles in various applications. Thermoresponsive graft copolymers, poly (N-isopropylacrylamide)-g-hyaluronic acid (PNIPAAm-g-HA) and elastin-like peptide-g-hyaluronic acid (ELP-g-HA), were synthesized by coupling carboxylic polymers (PNIPAAm-COOH or ELP) to biocompatible HA through amide linkages. Thermoresponsive behavior was observed in both the copolymers, and the results of turbidity measurement were consistent with the results of rheological examination. Among the two copolymers, the ELP graft copolymer shows less cooperative LCST transition than the PNIPAAm case. As the content of graft chains of PNIPAAm and ELP increases, viscosity increases, and the increase was larger in PNIPAAm case at a graft content. These results shows us that the introduction of grafts provides thermosensitivity to biocompatible HA, whose characteristics can be engineered.

• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.513-521
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• 2018

Purpose : : In this study, we made dopamine-functionalized hydrogels containing a cross-linked hyaluronic acid (HA) network and investigated their antioxidant activities. Methods : In the first step, we made poly hydroxyethyl methacrylate(p(HEMA))-based hydrogels post-modified with an interpenetrating polymer network(IPN) structure composed of HA polymers and a p(HEMA) network. The subsequent functionalization with dopamine via an amide coupling reaction resulted in the antioxidant hydrogels. Their antioxidant activities were evaluated using 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays. Results : The dopamine-modified hydrogels exhibited significant antioxidant activities, when compared to unmodified control. The presence of the HA-IPN structure improved the surface wettability of the hydrogel while dopamine-conjugated IPN hydrogel did not demonstrate the significant difference compared to hydrogel control. Dopamine-modified hydrogels exhibited high transmittance (>88%). Conclusion : The results demonstrate that the development of antioxidant hydrogels based on dopamine-conjugated HA-IPN structures may help develop ophthalmic and biomedical materials.

• Korean Journal of Veterinary Research
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• v.46 no.4
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• pp.305-313
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• 2006

The primary goal of the wound healing is rapid wound closure. Recent advances in cellular and molecular biology have greatly expanded our understanding of the biologic processes involved in wound repair and tissue regeneration. This study was conducted to develop a new sponge type of biomaterial to be used for either wound dressing or scaffold for tissue engineering. We designed to make a comparative study of the wound healing effect of silk fibroin/hyaluronic acid (SF/HA) blend sponge in full-thickness dermal injury model of rat. Two full-thickness excisions were made on the back of the experimental animals. The excised wound was covered with either the silk fibroin (SF), hyaluronic acid (HA) or SF/HA (7 : 3 or 5 : 5 ratio) blend sponge. On the postoperative days of 3, 7, 10 and 14, the wound area was calculated by image analysis software. Simultaneously, the tissues were stained with Hematoxylin-Eosin and Masson's trichrome methods to measure the area of regenerated epithelium and collagen deposition. In addition, we evaluated the degree of the epithelial cell proliferation using immunohistochemistry for proliferating cell nuclear antigen (PCNA). We found that the half healing time ($HT_{50}$) of SF/HA blend sponge treated groups were significantly decreased as compared with either those of SF or HA treatment group. Furthermore, SF/HA blend sponges significantly increased the size of epithelialization and collagen deposition as well as the number of PCNA positive cells on epidermal basement membrane as compared with those of control treatment. Especially, the 5 : 5 ratio group of SF/HA among all treatment groups was most effective on wound healing rate and histological studies. These results suggest that SF/HA blend sponges could accelerate the wound healing process through the increase of epithelialization, collagen deposition and basal cell proliferation in full thickness skin injury.

• Clinical Pain
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• v.19 no.1
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• pp.8-15
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• 2020

Objective: To compare the therapeutic efficacy of the bone marrow aspirate concentrate (BMAC)- platelet-rich plasma (PRP) complex with hyaluronic acid in patients with knee osteoarthritis. Method: Thirty-four patients with knee osteoarthritis participated in this study. Seventeen patients in the study group underwent BMAC and PRP extraction followed by intra-articular injection of BMAC-PRP complex within affected knee. Seventeen patients in the control group underwent intra-articular injection of hyaluronic acid. Knee injury, osteoarthritic outcome score (KOOS), and EuroQol-5D (EQ-5D) questionnaire were evaluated before, one month, three months, and six months after the injection. Results: There were statistically significant temporal differences in total KOOS scores in both BMAC-PRP and HA groups. However, there were no significant group difference in the study period. In the Sports and Recreational Function Scale, there was statistically significant improvement in the BMAC-PRP group compared to the HA group at three months (p=0.041). There were no side effects or complications in both groups. Conclusion: Intra-articular injection of BMAC-PRP showed better functional recovery in the OA at three months and this can be an alternative treatment in terms of functional recovery in the OA in addition to the decrease of pain.

• Clinics in Shoulder and Elbow
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• v.24 no.3
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• pp.147-155
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• 2021

Background: This study aimed to evaluate the co-administration effect of atelocollagen combined with hyaluronic acid (HA) injections for treatment of full-thickness rotator cuff tear (RCT). Methods: Eighty patients who underwent arthroscopic rotator cuff repair for full-thickness RCT from March 2018 to November 2019 were enrolled. The patients were randomly allocated to the following groups: combined atelocollagen and HA injection (group I, n=28), only HA injection (group II, n=26), and no injection (group III, n=26). Clinical outcomes were assessed at 3, 6, and 12 months after surgery using the American Shoulder and Elbow Surgeons score, visual analog scale pain score, functional scores (pain visual analog scale, function visual analog score), and range of motion. Magnetic resonance imaging was performed 12 months after surgery to evaluate rotator cuff integrity. Results: Preoperative demographic data and postoperative clinical outcomes did not differ significantly among the three groups (p>0.05). However, in group I, the number of steroid injections after surgery was significantly lower than that in the other groups (p=0.011). The retear rate on follow-up magnetic resonance imaging was significantly higher in group II (9.5%, n=2) and group III (13.6%, n=3) than in group I (0%) (p=0.021). Conclusions: Co-administration of atelocollagen and HA improves healing of the rotator cuff and increases the integrity of the rotator cuff repair site. This study provides encouraging evidence for use of combined atelocollagen-HA injections to treat patients with full-thickness RCT.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.42-48
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• 2003

This study was performed to compare the effect of hyaluronic acid(HA), vitamin I and their combinations for the prevention of postoperative intraperitioneal adhesion in dogs. Twelve mongrel dogs were divided into four groups; HA- (HA Group), vitamin E 800IU- (E8 Group), HA + vitamin E 800IU- (HA+E8 Group) and HA + vitamin E 1600IU-treated group(HA+E16 Group) with three dogs in each group. After celiotomy, five abrasions of 1$\times$1 cm area were made on the antimesenteric serosal surface of the anterior ileocecum with a No. 10 scalpel blade. The five abrasions and peritoneal cavity were coated with 25 of 0.l% HA. Oral supplements of vitamin E were given from the fifth day before the operation to the fourteenth day after the operation. Hematologic values were evaluated before the operation and on the 1st, 4th, 7th and 14th day after the operation. The locations and scores of adhesion were assessed through the second operation on the 21st day after the first operation. The adhesions were located on serosa to mesentary(43.3%)), serosa to serosa(20%), serosa to omentum(5%) and serosa to parietal peritoneum(1.7%). The incidences of adhesion in HA, E8, HA+E8 and HA+E16 groups were 80%, 100%, 47% and 53%, respectively. The scores of adhesion in HA+E8 group(p < 0.05) were lower than those in other groups. This study showed that the combination of HA and vitamin E 800IU was significantly effective in reducing the intraperitoneal adhesion in dogs.

• Polymer(Korea)
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• v.29 no.6
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• pp.599-604
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• 2005

The hyaluronic acid (HA) with excellent biocompatibility has been combined with lactide, the ester dimer of polylactide, with good biodegradability to produce biocompatible materials which can control the period of degradation in a human body. By freeze frying method, HA and lactide were crosslinked with crosslinking agent, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC). Degree of lactide and EDC reaction was determined by the analysis of nuclear magnetic resonance spectroscopy. Both lactyl group and EDC conversion increased as the mole ratio of lactide to HA increased from 5 to 13. The membrane swelled less and became more brittle with the more addition of lactyl group resulting from the higher mole ratio of lactide to HA. Swelling ratio decreased and tensile modulus increased due to the more addition of lactyl group as the EDC concentration increased or reaction temperature decreased. Drug release experiment from various membranes with different degree of crosslinking showed that permeability decreased with increasing degree of crosslinking. The degradation became slower with the more addition of lactyl group. Mechanical property and degradation rate of the synthesized membrane were shown to be controlled through adjusting operation parameters such as mole ratio, temperature, and crosslinking agent concentration.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.302-304
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• 2018

We, for the first time, isolated and identified a Vibrio splendidus KCTC 11899BP producing hyaluronate lyase from seawater. This enzyme is produced only when hyaluronic acid (HA) is added to the basal medium. Hyaluronate lyases are produced by microorganisms, which degrade the ${\beta}$-(1, 4) bond of HA to produce disaccharide. The genome of KCTC 11899BP, which consist of two circular contigs that are 3,522 kb (contig 1) long and 1,986 kb (contig 2) long respectively, as like other Vibrio sp. that contained 2 chromosomes. The genome included 4,700 predicted open reading frames, G + C content 44.12%, 137 tRNA genes, and 46 rRNA genes.

• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.761-769
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• 2018

BACKGROUND: Bioprinting has recently appeared as a powerful tool for building complex tissue and organ structures. However, the application of bioprinting to regenerative medicine has limitations, due to the restricted choices of bio-ink for cytocompatible cell encapsulation and the integrity of the fabricated structures. METHODS: In this study, we developed hybrid bio-inks based on acrylated hyaluronic acid (HA) for immobilizing bio-active peptides and tyramine-conjugated hyaluronic acids for fast gelation. RESULTS: Conventional acrylated HA-based hydrogels have a gelation time of more than 30 min, whereas hybrid bio-ink has been rapidly gelated within 200 s. Fibroblast cells cultured in this hybrid bio-ink up to 7 days showed >90% viability. As a guidance cue for stem cell differentiation, we immobilized four different bio-active peptides: BMP-7-derived peptides (BMP-7D) and osteopontin for osteogenesis, and substance-P (SP) and Ac-SDKP (SDKP) for angiogenesis. Mesenchymal stem cells cultured in these hybrid bio-inks showed the highest angiogenic and osteogenic activity cultured in bio-ink immobilized with a SP or BMP-7D peptide. This bio-ink was loaded in a three-dimensional (3D) bioprinting device showing reproducible printing features. CONCLUSION: We have developed bio-inks that combine biochemical and mechanical cues. Biochemical cues were able to regulate differentiation of cells, and mechanical cues enabled printing structuring. This multi-functional bio-ink can be used for complex tissue engineering and regenerative medicine.