• Korean journal of applied entomology
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• v.32 no.1
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• pp.24-29
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• 1993

Experiments were conducted to study effects of different bioassay methods on toxicity to the German cockroach (Blattella germanica L.) ith six insecticides. For male adults, by dry film method, the {TEX}$LC_{50}${/TEX} value of chlorpyrifos. fenvalerate, propoxur, permethin, DDVP, and hydramethylnon was 1.79, 1.87, 3.04, 4.37, 32.72, and 270.81 ppm, respectively and the same tendency was shown in the female. For male adults, by topical micro-application method, the {TEX}$LD_{50}${/TEX} value of DDVP and fenvalerate, chlorpyrifls, permethrin, propoxur, hydramethylnon was 2.63, 3.79, 4.51, 6.73, 44.99 $\mu\textrm{g}$/g, respectively and the same tendency was shown in the female. From the diet toxicity method against male adults, the CT value (Concentration%$\times${TEX}$LT_{50}${/TEX}) showed that chlorpyrifos was rapid effective and hydramethylnon was residual effective.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.38
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• pp.11.1-11.8
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• 2016

Background: Silk cocoon is composed of multiple layers. The natural silk cocoon containing all layers was cut as a rectangular shape as defined as total group. The inner and outermost layers were removed from the total group and the remained mat was defined as the middle group. The objectives of this study was to compare the total group with the middle group as a barrier membrane for the guided bone regeneration. Methods: The effects of these materials on the cellular proliferation and alkaline phosphatase (ALP) expression of MG63 cells were explored. For comparing bone regeneration ability, bilateral bone defects were created in calvarial areas in ten adult New Zealand white rabbits. The defects were covered with silk membranes of the middle group, with silk membrane of the total group used as the control on the contralateral side. The defects were allowed to heal for 4 and 8 weeks. Micro-computerized tomography (${\mu}CT$) and histological examination were performed. Results: The middle group exhibited a higher MTT value 48 and 72 h after treatment compared to the total group. ALP expression was also higher in the middle group. The results of ${\mu}CT$ and histologic examination showed that new bone formation was significantly higher in the middle group compared to the total group 8 weeks postoperatively (P < 0.05). Conclusions: In conclusion, the middle layer of the silk cocoon supports guided bone regeneration better than unprocessed silk cocoon.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.4
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• pp.254-261
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• 2005

Dental statistics for Koreans are far from complete and the majority of previous researches have adopted techniques such as radiological analysis and sectioning of teeth for morphological information, which are time-consuming, less accurate and destructive. Thus, a new nondestructive method is necessary to get precise dental standardization data for Koreans. For the above purpose, each of the first premolars was scanned by a micro-CT (SkyScan, Belgium) with a resolution of $21.31{\mu}m$ at an interval of 0.022mm along the plane horizontally parallel to an occlusion plane. Internal and external morphological sections were measured and compared to the values in the average tooth size table for permanent teeth presented by G. V Black.

• International Journal of Industrial Entomology and Biomaterials
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• v.27 no.1
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• pp.209-217
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• 2013

The objective of this study was to evaluate the bone regeneration capability of silk membrane plus 3% 4-hexylresorcinol (3% 4-HR plus SM) in a rabbit calvarial defect model. Twenty New Zealand white rabbits were used in this study. Bilateral round shaped defects were created in the parietal bone (diameter: 8.0 mm). And the defects were covered with (1) 3% 4-HR plus SM, (2) collagen membrane (CM), (3) no graft material. After surgery, the animals were sacrificed at 4 weeks and 8 weeks. Bone regeneration was analyzed in each section by micro-computerized tomography (${\mu}$-CT). And Hematoxylin and eosin stains were used for histological analysis. As measured by ${\mu}$-CT analysis 4 weeks after surgery, the average of new bone formation in animals treated with 3% 4-HR plus SM was greater than that of animals treated with CM. and the difference was statistically significant. And well organized lamella bones were observed in the histological view of the 3% 4-HR plus SM group. Therefore, more bone regeneration was seen in animals treated with 3% 4-HR plus SM than in those treated with CM or uncovered control.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.293-298
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• 2012

Purpose: The aim of this study was to evaluate the bone regeneration ability of 1% tetracycline (TC)-loaded silk fibroin membrane (SFM), in a rabbit calvarial defect model. Methods: Twenty New Zealand white rabbits were used for this study. Bilateral round defects were made on the rabbit parietal bone, using trephine bur with an 8 mm diameter. TC-loaded SFM or SFM was covered on the right parietal bone defect, and the left parietal bone defects were uncovered for the control. The animals were humanely sacrificed at 4 or 8 weeks postoperatively. A micro-computerized tomography (${\mu}$-CT) of each specimen was taken for analysis of bone regeneration. Hematoxylin and Eosin stain were done to observe histological findings. Results: From the ${\mu}$-CT results, regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $7.80{\pm}5.87$, $8.79{\pm}3.44$, and $10.61{\pm}5.3$ at 4 weeks postoperatively, respectively (P>0.05). Regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $36.56{\pm}8.50$, $25.86{\pm}8.17$, and $19.09{\pm}5.07$ at 8 weeks postoperatively, respectively (P<0.05). Conclusion: The 1% TC-loaded SFM showed more bone regeneration than the SFM and the uncovered control, in guided bone regeneration.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.4
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• pp.23-37
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• 2013

Objectives This study was performed to investigate the effects of Saengkanggamchotang (SKT) on the monosodium iodoacetate (MIA) induced osteoarthritis in rats. Methods Osteoarthritis was induced by injection of MIA (50 ul, 60 mg/ml) into knee joints of rats. Rats are divided into a total of 4 groups (normal, control, positive comparison group, SKT treated group, each n=6). Normal group are not treated at all without inducing osteoarthritis whereas control group were induced for osteoarthritis by MIA and oral medicated with 20 ml of distilled water per day. Positive comparison group was injected with MIA and after 7 days, that was taken indomethacin (30 mg/kg/mouse). SKT treated group was injected with MIA and after 7 days that was taken SKT (30 mg/kg/mouse). Positive comparison group and SKT treated group were oral medicated for each substance a total of 4 weeks with one time per day. After experiments (from 1 week after injection of papain to 4 weeks elapsed), the functions of liver and kidney, Prostaglandin E2, inflammatory cytokine (IL-$1{\beta}$, IL-6, TNF-${\alpha}$), osteocalcin, TIMP-1, MMP-9 within serum. Knee joint structures were observed by H&E, safranin-O staining method, and amount of cartilage were measured by ${\mu}CT$-arthrography. Results 1) Hind paw weight bearing ability was significantly improved. 2) Functions of liver and kidney were not affected. 3) Prostaglandin E2, osteocalcin, TIMP-1, MMP-9 in serum were significantly decreased. 4) Inflammatory cytokine IL-$1{\beta}$ was significantly decreased, and IL-6, TNF-${\alpha}$ were decreased but had not significant. 5) In terms of histopathology, significantly reduced subsidence of cartilage and bone in H&E staining. And in Safranin O staining, proteoglycan content in synovial membrane was significantly increased compared with control group. 6) Destruction of cartilage on ${\mu}CT$-arthrography was significantly reduced. Conclusions Based on all results mentioned above, Saengkanggamchotang (SKT) is believed to be meaningful for suppressing the progress of osteoarthritis and its treatments.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.4
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• pp.369-375
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• 2012

In order to overcome the detection limit by the current nondestructive evaluation technology, a nonlinear resonant ultrasound spectroscopy(NRUS) technique was applied for detection of micro-scale cracks in a material. A down-shift of the resonance frequency and a variation of normalized amplitude of the resonance pattern were suggested as the nonlinear parameter for detection of micro-scale cracks in a materials. A natural-like crack were produced in a standard compact tension(CT) specimen by a low cycle fatigue test and the resonance patterns were acquired in each fatigue step. As the exciting voltage increases, a down-shift of resonance frequency were increases as well as the normalized amplitude decrease. This nonlinear effects were significant and even greater in the cracked specimen, but not observed in a intact specimen.

• Journal of Trauma and Injury
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• v.26 no.3
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• pp.74-80
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• 2013

Purpose: There are no detailed reports on the incidence of venous thromboembolism (VTE) in pelvic and acetabular fractures in the Asian population. The purpose of this study was to investigate the incidence of VTE in pelvic and acetabular fractures in the Korean population. Methods: The cases of 67 Korean patients with pelvic and acetabular fractures treated at our hospital from January 2009 to February 2012 were analyzed retrospectively. Until May 2010, VTE screening was performed by contrast-enhanced computed tomography (CT) or ultrasonography (US) when the D-dimer value did not decline predictably, still exceeded $20{\mu}g/ml$ at 5 days after trauma and surgery, or increased to greater than $20{\mu}g/ml$ after a period of decline. After May 2010, contrast-enhanced CT and US were performed routinely irrespective of the D-dimer value. Physical prophylaxis was performed on all patients. The effects of the presence of a pelvic and/or acetabular fracture, and the effects of fracture type, accompanying injuries, and screening strategies on the incidences of VTE were investigated. Results: Overall, 26 patients(38.8%) were diagnosed with VTE and PTE in 14(20.9%). All were asymptomatic. Significantly higher incidences of VTE and PTE were observed in trauma patients with pelvic and acetabular fractures than in trauma patients without pelvic and acetabula fractures treated during the same period. No significant differences were observed in the incidences of VTE and PTE between patients with pelvic fractures, and patients with acetabular fractures or between patients with and without accompanying injuries. Compared with the previous screening strategy, the detection rates for VTE and PTE were higher for the newer screening strategy; however, the difference did not reach statistical significance. Conclusion: In the Korean population, we should be vigilant for a high incidence of VTE, especially PTE, in patients with pelvic and acetabular fractures.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.1
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• pp.25-49
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• 2013

Objectives : This study was carried out to know the anti-osteroarthritic effects of Bangkibokryeong-tang(Fanjifuling-tang(BBT)) on the papain-induced osteoarthritis C57BL/10 mouse. Methods : Osteoarthritis was induced by injection of papain(6 ${\mu}l$) into knee joint of mouse. Osteoarthritic mice were divided into 4 groups(normal, control, joins(R), BBT). The injection did not fit the normal group. A week later, after the injection of papain, control group was taken normal saline 200 ${\mu}l$, positive control group was taken joins(R)(100 mg/kg), treated group was taken extract of Bangkibokryeong-tang(Fanjifuling-tang(BBT))(400 mg/kg). After then, we examined hepatotoxicity, nephrotoxicity, inflammation cytokines, expression of inflammation factor mRNA, hemotology, histology through the micro CT-arthrography, and etc. Results : 1. Hepatotoxicity and nephrotoxicity have not expressed. 2. The levels of IL-$1{\beta}$, TNF-${\alpha}$, IL-6, MCP-1, Thromboxane B2, Leukotriene B4, Prostaglandin E2 in serum were significantly decreased. 3. In hematology, the levels of neutrophils and monocytes were significantly decreased. 4. The expression of inflammation factor mRNA like TNF-${\alpha}$ and IL-6, COX-2, iNOS-II were significantly inhibited. 5. In micro CT-arthrography, cartilage volume was less decreased. 6. The degree of osteoarthritis induced damage of joint of BBT group is low in histopathologic observation(hematoxylin&eosin(H&E), Safranin-O). Conclusions : According to this study, BBT has effect of anti-osteoarthritis. Further clinical research for the cartilage protective effect is necessary.

• Biomedical Science Letters
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• v.15 no.1
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• pp.87-91
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• 2009

In photodynamic therapy (PDT), oxygen plays important role. Because of singlet oxygen which is produced by activated photosensitizer after laser irradiation of specific wavelength. The aim of this study is to find how oxygen concentration affects anticancer effect in PDT. Groups were divided into PDT with oxygen applied group and only PDT applied group. PDT with oxygen applied group supplied oxygen for 15 minute before laser irradiation. In vitro, CT-26 cell was incubated with various concentration of photofrin $(50.0{\sim}0.05{\mu}g/ml)$ and was irradiated with 632nm diode laser 6hr after application of photofrin. The cell viability of two groups was assessed by MTT assay. In vivo, CT-26 cell line was transplanted into the subcutaneous tissue of BALB/c mouse. The anticancer effect of two groups was measured by tumor volume change. In vitro study, the cell viability was significantly decreased at $1.56{\sim}3.13{\mu}g/ml$ in PDT with oxygen applied group. In vivo study, the PDT with oxygen applied group significantly higher reduction rate of tumor volume 7 days after PDT compared to PDT only group. The high oxygen concentration might enhance the anticancer effect of the photodynamic therapy.