• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.5
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• pp.35-42
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• 2014

Thermal analysis properties and adhesive properties of self-healing agents were evaluated through differential scanning calorimetry, reaction heat measurement, and adhesive shear test. D1E0, D3E1, D1E1, D1E3, and D0E1, depending on the mixing ratio of DCPD and ENB, were considered as self-healing agents. The amount of Grubbs' catalyst, depending on the type of self-healing agents, was varied from 0.1 wt% to 1.5 wt%. In the case of DCPD, the polymerization reaction occurred faster and the stabilized adhesive strength increased as the amount of catalyst increased; however, a large amount of catalyst was required. ENB had excellent reactivity with a small amount of the catalyst; however, high reaction heat was observed at the early stage of polymerization. Thermal analysis properties and adhesive properties of self-healing agents can be controlled by varying a mixing ratio of DCPD and ENB. Among the self-healing agents used for this study, the D3E1 would be one of the most preferable candidates with regard to maximum adhesive strength, reaching time to maximum adhesive strength, stabilized adhesive strength, and reaction heat.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.173-177
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• 2013

Backgrounds: Tanshinone IIA (TIIA), a phenanthrenequinone derivative extracted from Salvia miltiorrhiza BUNGE, has been reported to be a natural anti-cancer agent in a variety of tumor cells. However, the effect of TIIA on gastric cancer cells remains unknown. In the present study, we investigated the influence of TIIA on the malignant phenotype of SGC7901 gastric cancer cells. Methods: Cells cultured in vitro were treated with TIIA (0, 1, 5, $10{\mu}g/ml$) and after incubation for different periods, cell proliferation was measured by MTT method and cell apoptosis and cell cycling were assessed by flow cytometry (FCM). The sensitivity of SGC7901 gastric cancer cells to anticancer chemotherapy was investigated with the MTT method, while cell migration and invasion were examined by wound-healing and transwell assays, respectively. Results: TIIA (1, 5, $10{\mu}g/ml$) exerted powerful inhibitory effects on cell proliferation (P < 0.05, and P < 0.01), and this effect was time- and dose-dependent. FCM results showed that TIIA induced apoptosis of SGC7901 cells, reduced the number of cells in S phase and increased those in G0/G1 phase. TIIA also significantly increased the sensitivity of SGC7901 gastric cancer cells to ADR and Fu. Moreover, wound-healing and transwell assays showed that TIIA markedly decreased migratory and invasive abilities of SGC7901 cells. Conclusions: TIIA can reverse the malignant phenotype of SGC7901 gastric cancer cells, indicating that it may be a promising therapeutic agent.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.38
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• pp.16.1-16.9
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• 2016

Background: The association of biomaterial combined with repair factor-like platelet-rich plasma (PRP) has prospective values. Bovine-derived xenograft has been identified as an osteoconductive and biocompatible grafting material that provides osseointegration ability. PRP has become a valuable adjunctive agent to promote healing in a lot of dental and oral surgery procedures. However, there are controversies with respect to the regenerative capacity of PRP and the real benefits of its use in bone grafts. The purpose of this study was to assess the influence of PRP combined with xenograft for the repair of peri-implant bone defects. Methods: Twelve rabbits were used in this study, and the experimental surgery with implant installation was performed simultaneously. Autologous PRP was prepared before the surgical procedure. An intrabony defect (7.0 mm in diameter and 3.0 mm deep) was created in the tibia of each rabbit; then, 24 titanium dental implants (3.0 mm in diameter and 8.5 mm long) were inserted into these osteotomy sites. Thus, a standardized gap (4.0 mm) was established between the surrounding bony walls and the implant surface. The gaps were treated with either xenograft alone (control group) or xenograft combined with PRP (experimental group). After healing for 1, 2, 3, 4, 5, and 6 weeks, the rabbits were sacrificed with an overdose of KCl solution. Two rabbits were killed at each time, and the samples including dental implants and surrounding bone were collected and processed for histological analysis. Results: More newly formed bone and a better bone healing process were observed in control group. The histomorphometric analysis revealed that the mean percentage of bone-to-implant contact in the control group was significantly higher than that of the experimental group (25.23 vs. 8.16 %; P < 0.05, independent-simple t test, analysis of variance [ANOVA]). Conclusions: The results indicate that in the addition of PRP to bovine-derived xenograft in the repair of bone defects around the implant, PRP may delay peri-implant bone healing.

• Archives of Plastic Surgery
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• v.40 no.6
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• pp.697-704
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• 2013

Background We conducted an experimental study to compare the effect of massage using topical agents (Kelo-cote or Contractubex) on scar formation by massaging the healed burn wound on the dorsal area of Sprague-Dawley (SD) rats. Methods Four areas of second degree contact burn were made on the dorsal area of each of 15 SD rats, using a soldering iron 15 mm in diameter. After gross epithelialization in the defect, 15 SD rats were randomly divided into four groups: the Kelo-cote group, Contractubex group, Vaseline group, and control group. Rats in three of the groups (all but the Control group) were massaged twice per day for 5 minutes each day, while those in the Control group were left unattended. For histologic analysis, we performed a biopsy and evaluated the thickness of scar tissue. Results In the Kelo-cote and Contractubex groups, scar tissue thicknesses showed a significant decrease, compared with the Vaseline and control groups. However, no significant differences were observed between the Kelo-cote and Contractubex groups. In the Vaseline group, scar tissue thicknesses showed a significant decrease, compared with the control groups. Conclusions The findings of this study suggest that massage using a topical agent is helpful in the prevention of scar formation and that massage only with lubricant (no use of a topical agent) also has a considerable effect, although not as much as the use of a topical agent. Thus, we recommend massage with a topical agent on the post-burn scar as an effective method for decreasing the scar thickness.

• BMB Reports
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• v.47 no.10
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• pp.581-586
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• 2014

Epidermal growth factor (EGF) is known to play key roles in skin regeneration and wound-healing. Here, we demonstrate that Pep2-YAC, a tripeptide covering residues 29-31 in the B loop of EGF, promotes the proliferation of HaCaT keratinocytes with activity comparable to EGF. The treatment of HaCaT cells with Pep2-YAC induced phosphorylation, internalization, and degradation of EGFR and organization of signaling complexes, which consist of Grb2, Gab1, SHP2, and PI3K. In addition, it stimulated the phosphorylation of ERK1/2 at Thr 202/Tyr 204 and of Akt1 at Ser 473 and the nuclear translocation of EGFR, STAT3, c-Jun, and c-Fos. These results suggest that Pep2-YAC may be useful as a therapeutic agent for skin regeneration and wound-healing as an EGFR agonist.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.2
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• pp.179-185
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• 2000

The purpose of this study was to develop an osteogenic, biodegradable material using polymer and BMP. It was designed to have structural function and be moldable, for the reconstruction of load bearing areas and deformities of various configurations. Bone apatite was added to Poly(L-lactide)(PLLA) and made porous for osteoconductability and ease of BMP loading. The materials, with or without BMP purified from porcine bone matrix, were evaluated in cranial bone defect models in rats for biocompatibility and bone regeneration capability. The following results were obtained: The PLLA-BMP material with BMP added to the polymer showed 30% healing of cranial bone defects in rats during the 2 weeks to 3 months period of observation. The moldable PLLA agent without BMP also showed 25% bone healing capacity. Although new bone formation was incomplete in the critical size defect of rat cranium, it can be concluded that the unique moldability of those agents makes them useful for the reconstruction of various bone defects and maxillofacial deformities.

• English & American cultural studies
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• v.18 no.4
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• pp.1-31
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• 2018

It is needless to say that America's indiscriminate artillery and chemical attacks have worsened the conditions of Vietnam's tropical rain forests, causing war-torn combat troops and civilians to suffer more from the participation and aftermath of the Vietnam war. Around two decades after the Vietnam War, American and Vietnamese writers dealing with the destruction of the human and nature of the Vietnam War and the following traumatic experience commonly report the horrors of inhumane warfare, but some differences among them appear in the reception of the ecocide consciousness. For American writers who had been involuntarily involved or who had stayed in the back area as interpreters and counter-intelligence force, the Vietnam War was often a kind of exotic "addicted adventure" which their American hometown could not provide. But apart from overcoming postwar post-traumatic stress by writing of healing which was shared with American war writers, Vietnamese writers have been able to overcome the scars of war as the communal memorial, which Jonathan Shay emphasized as the necessary comforting ritual by community members showing the sign of honor and care. On the other hand, American war writers were on the side of "separate peace," as Jeong stressed, and the Vietnam War to them was more racist like the case of "body count." Nevertheless, it is fortunate that the hideous experience of war could turn them all into the creativity pool, just as the 5,000 square mile of bomb creators have been used as the postwar fish ponds.

• Natural Product Sciences
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• v.27 no.1
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• pp.1-9
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• 2021

Methicillin-resistant Staphylococcus aureus (MRSA) infection often complicates burn wounds. Mupirocin is the antibiotic of choice for superficial MRSA infection, and its resistance is on the rise due to its frequent and widespread use. This study aimed to develop and evaluate Curcuma xanthorriza extract (CXE)-containing gel as a topical agent against MRSA-infected second-degree burn wound in rats. CXE was obtained using maceration with 96% ethanol. Xanthorrhizol level, antibacterial, and antioxidant activity were evaluated using a standardized method. In vivo, the wound's healing and bacterial load were evaluated every three days, whereas the histopathology of the wound was examined on day 12 of treatment. One-Way ANOVA and Kruskal-Wallis test were used to analyze the data. In this study, 27.0% and 7.10% of the obtained CXE were xanthorrhizol and curcumin, respectively. Additionally, an IC50 of 64.27 ppm was shown in antioxidant activity measurement, and MIC against MRSA was 5 mg/ml. Treatment with CXE-containing gels showed a significant reduction in bacterial load and proliferation of connective tissue in a dose-dependent manner. In conclusion, CXE-containing gel showed a greater reduction of bacterial load and more advanced wound healing phase than mupirocin.

• Journal of Korean Foot and Ankle Society
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• v.21 no.4
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• pp.151-155
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• 2017

Purpose: Reducing tenderness or pain on the ankle joint and improving the range of motion are thought to be possible using hyaluronate-based anti-adhesive agents. On the other hand, there are more aspects to be studied regarding the incidence of complications, such as resting pain, tenderness, and stiffness, after surgery. Therefore, the aim of this study was to prove the effectiveness of the agents after ankle fracture surgery. Materials and Methods: Patients, who underwent open reduction and internal fixation surgery due to ankle joint fractures from June 2015 to May 2016, were studied prospectively. Thirty patients of them received a $Guardix^{(R)}$ injection during their surgeries and were included in the injection group. The other 30 patients were included in the control group. Postoperatively, tenderness on the scar, a delay in wound healing, and the active range of motion were evaluated at 2, 6, and 12 weeks after surgery. Results: A significant difference in tenderness on the scar was observed 2 weeks after surgery. On the other hand, there was no significant difference at 6 and 12 weeks after the surgery. The agent-using group showed a 6.7% delay in wound healing and a 93.3% nondelaying. In the non-using group, the delay was 63.3%, while non-delay was 36.7% (p<0.001). The group that underwent $Guardix^{(R)}$ usage showed an effective result in the visual analogue scale, which was statistically significant (p<0.001). The result at 6 and 12 weeks after surgery showed a significant difference. Conclusion: Improvement was observed in the patients who underwent a $Guardix^{(R)}$ injection, regarding the range of motion, visual analog scale, and healing of the wound postoperatively.

• Applied Microscopy
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• v.43 no.4
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• pp.133-139
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• 2013

This study was carried out to investigate the effects of pycnogenol (PYC) on the cutaneous wound healing of the mice. The wounds were extracted on days 1, 3, 5, and 7 post-injury for histomorphometrical analysis including wound area, infiltrating inflammatory cells, wound contracture including collagen deposition. As the result, the wound area of PYC-treated group was larger than the control group on days 1 to 7. Inflammatory cells in the PYC-treated wounds were decreased at day 1 compared to the control wound tissue. From day 3 to 7, there was no significant difference between the control and the PYC-treated skin wounds. Though the degree of contraction in the PYC-treated group was lower than that of the control group from days 1 to 5, but appeared significantly higher on day 7. Compared to the control group, collagen accumulation in the PYC-treated group was higher than that of the control group from days 5 to 7. From this result, it may support the possibility that PYC would be useful agent for early inflammatory response and matrix remodeling phase of the skin wounds.