• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.6
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• pp.485-493
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• 2007

Introduction: Although several types of calcium-phosphate coumpound have been frequently applied to osseous defects at maxillofacial area for many years, there is a controversy about its efficiency on bone conductivity comprared to xenograft bone substitute. Alloplastic carbonapatite has been introduced to improve disadvantages of hydroxyapatite and to mimic natural bone containing carbon elements. However, a preclinical study about its efficiency of osteoconductivity has not been reported. This study was performed to evaluate the early osteoconductive potential of synthetic carbonapatite with multiple pores relative to anorganic bovine xenograft. Materials and methods: Total 5 beagle dogs were used for maxillary augmentation model. The control (anorganic bovine xenograft) and experimental groups (synthetic carbonapatite) were randomly distributed in the mouth split design. After bone graft, all animals were sacrificed 4 weeks after surgery. Histological specimens with Masson Trichrome staining were made and histomorphometrically analysed with image analyser. The statistical analysis was performed using paired t-test. Results: In both groups, all animals had no complications. The experimental group showed relatively much new bone formation around and along the bone substitutes, whereas it was clearly reduced in the control group. The ratios of new bone area to total area, to material area and to the residual area excluding materials were higher in the experimental group ($0.13{\pm}0.03,\;0.40{\pm}0.13,\;0.20{\pm}0.06$ respectively) than in the control group ($0.01{\pm}0.01,\;0.03{\pm}0.02,\;0.03{\pm}0.03$, respectively). And the differences between both groups were statistically significant (p<0.001, <0.01, <0.01, respectively), while the ratio of material area to total area in two groups was not significant. Conclusion: Carbonapatite showed a high osteoconductivity in the early stage of bone healing compared to bovine derived anorganic bone substitute. This study suggests that this bone materials can be applied as a reliable bone substitute in the clinical treatment.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.6
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• pp.544-549
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• 2009

Failure to use effective methods of reduction, fixation and immobilization may lead to osteomyelitis with the exposed necrotic bone, as the overzealous use of transosseous wires & plates that devascularizes bone segments in the compound comminuted fractures of mandible. Once osteomyelitis secondary to fractures has become established, intermaxillary fixation should be instituted as early as possible. Fixation enhances patient comfort and hinders ingress of microorganisms and debris by movement of bone fragments. Teeth and foreign materials that are in the line of fracture should be removed and initial debridement performed at the earliest possible time. Grossly necrotic bone should be excised as early as possible ; no attempt should be made to create soft tissue flaps to achieve closure over exposed bone. The key to treatment of chronic osteomyelitis of the mandible is adequate and prolonged soft tissue drainage. If good soft tissue drainage is provided over a long period, sequestration of infected bone followed by regeneration or fibrous tissue replacement will occur so that appearance and function are not seriously altered. Localization and sequestration of infected mandible are far better performed by natural mechanism of homeostasis than by cutting across involved bone with a cosmetic or functional defect. As natural host defenses and conservative therapy begin to be effective, the process may become chronic, inflammation regresses, granulation tissue is formed, and new blood vessels cause lysis of bone, thus separating fragments of necrotic bone(sequestra) from viable bone. The sequestra may be isolated by a bed of granulation tissue, encased in a sheath of new bone(involucrum), and removed easily with pincettes. This is a case report of the long-term conservative drainage care in osteomyelitis associated with mandibular fractures.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.207-216
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• 2015

The study was conducted to determine the effects of forest restoration methods and stand structure on solar radiation, air temperature, relative humidity, soil temperature, and soil water content, based on volume, in forest stand after forest fire. The changes of the micro-climate elements in naturally and artificially restored forest after forest fire were measured in Goseong and Samcheok, Gangwon province. Pinus spp. were commonly appeared in ridges, barren lands or planted areas of the study sites while the other areas were dominated by Quercus spp. In the early stage, trees in the naturally regenerated site grow better than the trees in artificially rehabilitated site. However, the growth ratio rapidly decreased by time passed in natural regeneration area. The environmental conditions (solar radiation, air temperature, relative humidity, soil temperature and soil water content) were significantly different by the regions and the methods (p<.05). However, the coefficients of variations of the environmental conditions were not significantly different at 95% confidence level. As the coverage and tree height in crown layer increased, the relative humidity and soil water content were increased while the temperature and solar radiation were decreased. Especially, the relative humidity, solar radiation, and soil water content were clearly affected by the tree height and coverage ratio ($R^2$ means from 0.628 to 0.924). Even though the data should have collected at least more than 5 years in meteorological analysis, the two year results show some clear relationship between forest structure and microclimate elements.

• Journal of Periodontal and Implant Science
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• v.33 no.2
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• pp.167-178
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• 2003

Many researches are being done to study the effect of toothpaste containing natural extracts. The aim of this study was to evaluate the plaque control effect and therapeutic effect of toothpaste products containing chitosan extract. 120 healthy subjects with gingivitis or early periodontitis were divided into two groups. Subjects in the experimental group only used toothpaste containing chitosan and subjects in the control group used toothpaste without chitosan. At first, subjects received scaling and tooth brushing instruction. Gingival index, bleeding index, probing pocket depth, probing attachment level were scored at baseline, 2 months, and 3 months, and plaque index were scored at baseline, 1 month, 2 months, 3 months. Gingival index of experimental group and control group at baseline, 2 months, and 3 months use were 0.71${\pm}$0.66, 0.49${\pm}$0.55, 0.36${\pm}$0.49 and 0.62${\pm}$0.58, 0.51${\pm}$0.52, 0.48${\pm}$0.50 (mean${\pm}$SD), respectively (statistically significant different at p <0.05 ). Plaque index of experimental group and control group at baseline, 1 month, 2 months, and 3 months were 0.52${\pm}$0.50, 0.43${\pm}$0.50, 0.39${\pm}$0.49, 0.29${\pm}$0.46 and 0.49${\pm}$0.50, 0.50${\pm}$0.50, 0.51${\pm}$0.50, 0.45${\pm}$0.50, respectively (statistically significant different at p<0.05 ). Bleeding index of experimental group and control group were 0.40${\pm}$0.49, 0.33${\pm}$0.47, 0.24${\pm}$0.43 and 0.40${\pm}$0.49,0,38${\pm}$0.49,0.30${\pm}$0.46, respectively (statistically significant different at p<0.05). Probing depth of experimental group and control group were 2.41${\pm}$0.64, 2.31${\pm}$0.60, 2.28${\pm}$0.55 and 2.51${\pm}$0.67, 2.47${\pm}$0.63,2.42${\pm}$0.62, respectively (statistically significant different at p${\pm}$0.66, 2.32${\pm}$0.62 and 2.54${\pm}$0.70, 2.51${\pm}$0.69,2.46${\pm}$0.66, respectively (statistically significant different at p<0.05 ). From these finding, it can be concluded that toothpaste containing chitosan have better plaque control effect and therapeutic effect on gingivitis and early periodontitis compared to conventional toothpastes.

• Journal of Periodontal and Implant Science
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• v.30 no.1
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• pp.91-104
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• 2000

Many synthetic bone materials have been studied for their potential of regenerative effects in periodontal tissue. Safflower seeds have been traditionally used as a drug for the treatment of fracture and blood stasis in oriental medicines. The purpose of this study was to assess and compare the osseous responses in rat calvarial defects between bone substitutes such as calcium carbonate and bovine-derived hydroxyapatite and feeding of safflower seeds. The calvarial defects were made with 8 mm trephine bur in 24 Sprague-Dawley rats. Two graft materials were implanted in each experimental groups, whereas the control and safflower seed feeding groups were sutured without any other treatment. And then the rats of safflower seed feeding group were supplied with 3 g/day of safflower seeds. Each group was sacrificed at 4 weeks and 8 weeks. To study a histopathology related to bone healing and regeneration, Goldner's Masson Trichrome stain was done at each weeks. The tissue response was evaluated under light microscope. There were more osteoblastic activity, new bone formation, dense bony connective tissues in bovine-derived hydroxyapatite group compared to other groups at 8 weeks. The osseous defect area of safflower seed feeding group was filled with prominent fibrous tissues, where less inflammatory infiltration and new capillary proliferation. In the early phase of bone healing, safflower seed feeding reduces the inflammatory response and promotes the proliferation of connective tissue. These results suggest that natural bovine-derived HA and safflower seed feeding could enhance the regenerative potential in periodontal defects.

• Journal of Animal Science and Technology
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• v.64 no.6
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• pp.1132-1143
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• 2022

Insects are a valuable natural source that can produce a variety of bioactive compounds due to their increasing species diversity. CopA3 is an antimicrobial peptide derived from Copris tripartitus (i.e., the dung beetle). It is known to increase the proliferation of colonic epithelial and neuronal stem cells by regulating cell cycle. This research hypothesized that CopA3 can promote the proliferation of porcine muscle satellite cells (MSCs). The effects of CopA3 on porcine MSCs, which are important for muscle growth and regeneration, remain unclear. Here, we investigated the effects of CopA3 on porcine MSCs. According to viability results, we designed four groups: control (without CopA3) and three treatment groups (treated with 5,10, and 25 ㎍/mL of CopA3). At a CopA3 concentration of 5 ㎍/mL and 10 ㎍/mL, the proliferation of MSCs increased more than that observed in the control group. Furthermore, compared to that in the control, CopA3 treatment increased the S phase but decreased the G0/G1 phase ratio. Additionally, early and late apoptotic cells were found to be decreased in the 5 ㎍/mL group. The expressions of the myogenesis-related transcription factor PAX7 and MYOD proteins were significantly upregulated in the 5 ㎍/mL and 10 ㎍/mL groups, whereas the MYOG protein remained undetected in all group. This study suggested that CopA3 promotes muscle cell proliferation by regulating the cell cycle of MSCs and can regulate the activity of MSCs by increasing the expressions of PAX7 and MYOD.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.323-330
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• 2010

This study was undertaken to compare early growth characteristics, such as height, diameter at root collar (DRC), and the dry weights of stem, branches, needles and roots between naturally regenerated and planted stands of Pinus densiflora for. erecta in Dae-gi and Bo-gwang site, Gangwon province, Republic of Korea. Average DRC growth was similar between the naturally regenerated and the planted stands in Dae-gi area, however, difference was statistically significant (P<0.01) between the naturally regenerated and the planted stands in Bo-gwang area, 4.66 cm and 2.61 cm, respectively. Average height of the naturally regenerated stands was significantly greater (P<0.01) than that of planted stands in both Dae-gi and Bo-gwang areas. The composition ratio of the dry weights for each part of measured trees was the highest in the stem in the naturally regenerated stands, but in the planted stands, the needle was the highest in both sites. The root/shoot ratio in the Dae-gi and Bo-gwang areas in the planted stands were much greater than those in the naturally regenerated stands, 0.25-0.30 and 0.17-0.18, respectively. The ratio of needle to stem biomass (N/S), branch to stem biomass (B/S), and needle to branch biomass (N/B) was significantly greater in the planted stands than those in the naturally regenerated stands in both sites. The results of this study represent that the regeneration methods, natural and artificial regenerations, can have an influence on the early growth of P densiflora for. erecta. This results not only provide the need for a correct planting method, but also will be useful in studies on the environmental adaptability of trees.

• Journal of Wetlands Research
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• v.1 no.1
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• pp.29-44
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• 1999

Vegetation structure and distribution of the vascular hydrophytes and hygrophytes, and the growth pattern, standing crop and amounts of nutrient uptake by Salix species were investigated in the upper stream wetlands of the Namgang-Dam, Chinju-city, Gyeongsangnam-do, Korea from April to November in 1997. The flora was composed of 43 hydrophytes and 241 hygrophytes, or total 284 vascular plants. The life forms of the hydrophytes were classified as 27 kinds of emergent plants, 4 floating-leaved plants, 3 free-floating plants, and 9 submersed plants. In the herb layer, the dominant species was Persicaria hyciropiper, and the ranges of the species diversity indices (H'), equitabilities, (J') and community similarity indices (CCs) were 1.59~1.89, 0.87~0.96, and 0.35~0.83, respectively. In the shrub and subtree layers, 17 kinds of Salix species were supposed to the pioneer plants at the early stage of the succession. The number of branches per main stem of Salix species was 5.0. The DBH class-frequency histograms of Salix species were the reverse J type, and the natural regeneration of the Salix community was expected. Basal area of Salix species per square meter was $24.87cm^2$. Volume of Salix species per square meter was $12,008cm^3$ and total phytomass of the Salix species was estimated as 12,894 ton. Biomass distribution of Salix species in the stem, the branch and twig, and the leaf was 64.1%, 28.1%, and 7.8%, respectively. The amounts of nitrogen and phosphorus absorbed by Salix species were 68,022 and 19,823 kg. It was recommended that application and conservation of the wetland and other counterplans are indispensable to reduce the adverse effects of water pollution and to preserve the wetland ecosystem.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.4
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• pp.183-189
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• 2000

This study was carried out to analyze ecophysiological responses for seedling of Quercus serrata, Quercus mongolica and Quercus variabilis that are the typical species of deciduous broadleaved forests in Korea. And executed experiments in the climatic control room to provide necessary information to ecological forest management and methods of natural regeneration through the analysis of seedling responses. The details of experimental analysis were growth processes of 4 months after seeding that vary with the condition of three light intensity[relative light intensity(RLI) 8%, 20%, 52%] and three soil moisture[water suction(WS) Ψ=100 hPa, Ψ=280 hPa, Ψ=330 hPa] gradient, growth factors after harvesting and the nutrition condition of leaves. The results of this study are followings: 1) Early growth was prosperous after germination for the species which have more weight of acorn. 2) The formation of lammas shoot was favourable with Q. variabilis and Q. mongolica. And the rate of the occurrence was the highest in the RLI 20%, and it was remarkably reduced in the RLI 8%. 3) As the height growth of seedling of all 3 species were greater in the RLI 20% and 8% than that of the RLI 52%, they showed strong shade tolerance. 4) The increase of light intensity promoted the diameter at root collar growth, and development of main and lateral roots with all 3 species. 5) It showed that the increase of light intensity in the experimental radiation condition raised special leaf area weight(mg/cm$^2$) and leaf area productivity(mg/cm$^2$). Consequently, these resulted in the increase of leaf thickness and total dry biomass per the unit area of leaf. 6) As the increase of light intensity, the minerals contents of leaves such as N, P and K were lowered, and the increase of soil moisture resulted in the increase of P, K, Ca and Mg.