• 대한치과보철학회지
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• 제33권2호
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• pp.317-334
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• 1995

The purpose of this study was to compare the bone formation, maturation around HA-and titaniumcoated dental implants in dog. 5 hydroxyapatite coated IMZ implants and 5 titanium coated IMZ implants were placed into the previously extracted site in the mandible of 5 adults dogs. All dogs were injected intravenously Tetracycline, Alizalin red S, and Calcein for bone fluorescent labelling, After the experimental period of 16weeks, the dogs were sacrificed and tissue samples around the implants were obtained. Microscopic observations(ligth, polariged and fluorescence microscope), morphometric analysis, line profile with EPMA, and quantitative analysis for Ca,P, and Ti were performed. The results were as follows ; 1. Bone maturations around the implants were relatively lower than those of natural teeth. No significant differences in bone maturation and remodeling patterns were observed between the two implants groups. 2. Calcification of bone surrounding the implants was initiated in 8-11 weeks for HA-coated implants, while it took 11 weeks or more for Ti-coated implants. 3. Bone-to-implants contact ratio of 82.63% was recorded for HA-coated group and 72.25% for titanium coated group, with no significant difference between the two groups. 4. Bone around the implants exhibited reduced quantity of Ca and P in the $100{\mu}m$ region relative to natural teeth, while the rest of the regions showed no statistical differences. No significant differences were found between the two implant groups. 5. There was a separation of HA layer from the implant core and subsequent infiltration of inflammatory cells into the resulting space in the HA-coated implants, and evidences of phagocytosis of HA particles by macrophages. Bone calcification was more rapid around HA-coated implants compared to titanium-coated implants, but HA coated implants did not show any significant differences either in the degree of calcification or the bone-to-implant contact ratio over Ti coated implants. HA coated implants may have complications associated with HA absorption and separation of HA layer from the implant core.

• 한방비만학회지
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• 제6권1호
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• pp.107-115
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• 2006

Objectives : It has been suggested that obesity in childhood may lead early menarche and rapid bony maturation. The purpose of this study is to investigate correlation between bone maturation and obese degree in childhood in Korea. Methods : Height, body weight, BMI, percent body fat were taken 138 patients. Ultrasonic scan was taken through calcaneous of the right foot to evaluate bone age. $DA({\Delta}age)$ was calculated from the difference of bone age and chronological age, and it was used in correlation with obese degree. Results : 1. The average age of patients was $11.91{\pm}2.86$ years old in boys, $11.44{\pm}2.27$ years old in girls. 2. The average BMI was $20.92{\pm}4.53kg/m2$ in boys, $19.76{\pm}4.05kg/m2in$ girls, and average percent body fat was $25.13{\pm}8.23%$ in boys, $27.66{\pm}5.95%$ in girls. 3. The average OI(osteo index) was 37.88 in boys, 36.64 in girls, and average bone age was $12.00{\pm}2.61$ years old in boys, $11.81{\pm}2.11$ years old in girls. 4. There was significant correlation between $DA({\Delta}age)$ and PBF in boys, but no significant correlation with BMI(p<0.05). 5. There was significant correlation between $DA({\Delta}age)$ and PBF, BMI in girls(p<0.01). 6. There was significant correlation between RA and OI(p<0.01). Conclusion : It is suggested that obese degree may have an impact on early bony maturation especially in case of girls.

• Journal of Periodontal and Implant Science
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• 제25권2호
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• pp.418-437
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• 1995

The effect of the hydroxyapatite coatings on Titanium implants has been the subject of recent investigations. So far, the use of HA coating remains substantially controversial.This study was aimed to evaluate histologically the bone healing patterns around titanium plasm sprayed(TPS) amd HA-coated implant after implantation into the femur neck of ten adult dogs. After implantation, animals were sacrificed at the intervals of 2,4,6,8 and 12 weeks.The fluorescent dyes were injected on the postoperative 4th and 12th week into the animals supposed to be killed at the 12th week. The morphology and direction of new bone formation was similar in both TPS and HA-coated implants.There was a tendency toward more bone formation in the cortical bone area than in the cancellous bone area. Histologically,in the interface of the HA-coated implants, bone response and bone maturation was faster, compared to the TPS implants in the 2nd and 4th week. By fluorescent microscopy, new bone formation was active in the 4th week around both implants and was directed from the periosteum overlying cortical bone to the cancellous bone. These results suggest that the bone formation and maturation is faster during the early healing stage in the interface of the HA-coated implant and where the cortical bone quality is poor, HA coated implant is superior to the TPS implant in the early phase of new bone formation.

• 한방비만학회지
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• 제7권2호
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• pp.61-75
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• 2007

Objectives : The purpose of this study was to investigate correlation between obese degree, result of hair tissue mineral analysis and bony maturation. And we also wanted to compare the differences between early bony maturation group(EBM) and late bony maturation group(LBM). Methods : 146 subjects who visited growth clinic were measured by BMI, PBF(percent body fat), percent BMI, bone age esimation and HTMA(hair tissue mineral analysis). The patients were classified into two groups - EBM, LBM group - according to the gap of bone age and chronological age. It was analysed that the correlation of bony maturation and obese degree, nutritional elements, heavy metals, significant ratio of nutritional elements. Also, analysed the differences between groups. Results : 1. BMI, percent BMI had a correlation with bony maturation, PBF however didn't have a correlation with it. 2. Ca, Mg, Zn and P had a positive correlation with bony maturation, and also K, Cr and Mo had a negative correlation. 3. U, As and Cd had a negative correlation with bony maturation. 4. Ca/P, Na/K, Ca/K and Zn/Cu had a positive correlation with bony maturation, and also Na/Mg, Ca/Mg had a negative correlation. 5. Percent BMI, Ca, Mg, Mn and Ca/p were higher in EBM group. 6. K, Mo and Hg were lower in EBM group. Conclusion : According to this study it could be suggested that maintaining proper percent BMI and accumulation of nutritional elements, heavy metals to prevent early bony maturation.

• BMB Reports
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• 제53권9호
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• pp.472-477
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• 2020

Osteoclasts are hematopoietic-derived cells that resorb bone. They are required to maintain proper bone homeostasis and skeletal strength. Although osteoclast differentiation depends on receptor activator of NF-κB ligand (RANKL) stimulation, additional molecules further contribute to osteoclast maturation. Here, we demonstrate that protocadherin-7 (Pcdh7) regulates formation of multinucleated osteoclasts and contributes to maintenance of bone homeostasis. We found that Pcdh7 expression is induced by RANKL stimulation, and that RNAi-mediated knockdown of Pcdh7 resulted in impaired formation of osteoclasts. We generated Pcdh7-deficient mice and found increased bone mass due to decreased bone resorption but without any defect in bone formation. Using an in vitro culture system, it was revealed that formation of multinucleated osteoclasts is impaired in Pcdh7-deficient cultures, while no apparent defects were observed in differentiation and function of Pcdh7-deficient osteoblasts. Taken together, these results reveal an osteoclast cell-intrinsic role for Pcdh7 in maintaining bone homeostasis.

• 식품보건융합연구
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• 제8권2호
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• pp.15-27
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• 2022

This study aims to analyze the relative importance of bone age and chronological age in physique according to gender and to identify the relative importance of bone age, chronological age, and physique in physical fitness and motor coordination according to gender in order to alleviate the imbalance between physique and physical fitness in children. A total of 666 children(346 males, 320 females) between the ages of 11-14 were enrolled as subjects, and the skeletal maturation The skeletal maturation were measured by taking hand-wrist. Physical fitness were measured through a total of 4 components: muscular strength. The results of this study. First, physique variables for both males and females aged 11-14 were found to be more significant predictors of bone age than chronological age. Second, for physical fitness in males, in the order of %fat, body water, waist-hip ratio, weight, fat-free mass, and chronological age were more significant predictor variables; and in females, in the order of %fat, fat-free mass, height, chronological age, weight, bone age, fat mass, and body water were more significant predictor variables. For bone age and chronological age in physical fitness, bone age in males and chronological age in females found to be the more representative variables respectively.

• Molecules and Cells
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• 제37권8호
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• pp.628-635
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• 2014

2-(Trimethylammonium) ethyl (R)-3-methoxy-3-oxo-2-stearamidopropyl phosphate [(R)-TEMOSPho], a derivative of an organic chemical identified from a natural product library, promotes highly efficient megakaryopoiesis. Here, we show that (R)-TEMOSPho blocks osteoclast maturation from progenitor cells of hematopoietic origin, as well as blocking the resorptive function of mature osteoclasts. The inhibitory effect of (R)-TEMOSPho on osteoclasts was due to a disruption of the actin cytoskeleton, resulting from impaired downstream signaling of c-Fms, a receptor for macrophage-colony stimulating factor linked to c-Cbl, phosphoinositol-3-kinase (PI3K), Vav3, and Rac1. In addition, (R)-TEMOSPho blocked inflammation-induced bone destruction by reducing the numbers of osteoclasts produced in mice. Thus, (R)-TEMOSPho may represent a promising new class of antiresorptive drugs for the treatment of bone loss associated with increased osteoclast maturation and activity.

• 대한본초학회지
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• 제22권3호
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• pp.127-132
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• 2007

Objectives : FLOS CHRYSANTHEMI (FC) has been reported to possess a variety of pharmacological activities. However, the effect of FC on the dendritic cells has not been determined. Methods : To examine the effect of FC on the immune response, we used several methods such as flow cytometric analyses, enzyme-linked immunosorbent assay. Results : 1. FC inhibited lipopolysacchride (LPS)-induced maturation of bone marrow-derived dendritic cells (BMDC) such as down-regulation of MHC class II and CD40. 2. FC also inhibited uptake of FITC-Dextran in BMDC stimulated with LPS. 3. Furthermore, FC inhibited several kinds of cytokine production such as TNF-a, IL-6 and IL-12 in BMDC. Conclusions : These results suggest that FC plays pivotal role m the development of inflammatory diseases.

• Journal of Periodontal and Implant Science
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• 제50권6호
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• pp.418-434
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• 2020

Purpose: The purpose of the present study was to evaluate the effect of silica-calcium phosphate composite (SCPC) granules on bone regeneration in extraction sockets. Methods: Ten patients were selected for a split-model study. In each patient, bone healing in SCPC-grafted and control ungrafted sockets was analyzed through clinical, radiographic, histomorphometric, and immunohistochemical assessments 6 months postoperatively. Results: A radiographic assessment using cone-beam computed tomography showed minimal ridge dimension changes in SCPC-grafted sockets, with 0.39 mm and 1.79 mm decreases in height and width, respectively. Core bone biopsy samples were obtained 6 months post-extraction during implant placement and analyzed. The average percent areas occupied by mature bone, woven bone, and remnant particles in the SCPC-grafted sockets were 41.3%±12%, 20.1%±9.5%, and 5.3%±4.4%, respectively. The percent areas of mature bone and woven bone formed in the control ungrafted sockets at the same time point were 31%±14% and 24.1%±9.4%, respectively. Histochemical and immunohistochemical analyses showed dense mineralized bundles of type I collagen with high osteopontin expression intensity in the grafted sockets. The newly formed bone was well vascularized, with numerous active osteoblasts, Haversian systems, and osteocytes indicating maturation. In contrast, the new bone in the control ungrafted sockets was immature, rich in type III collagen, and had a low osteocyte density. Conclusions: The resorption of SCPC granules in 6 months was coordinated with better new bone formation than was observed in untreated sockets. SCPC is a resorbable bone graft material that enhances bone formation and maturation through its stimulatory effect on bone cell function.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권3호
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• pp.158-163
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• 2009

Objective : Recently, we are interested in bisphosphonate related osteonecrosis of the jaw (BRONJ). Most of patients with osteonecrosis have taken medicine bisphosphonate for a long time. But the mechanism of osteonecrosis in BRONJ was not clarified yet. The aim of this study is to evaluate the difference of bone healing effect after bone graft from ilium to maxillary sinus in rabbits between zoledronate-treated and zoledronate-not treated groups. Method : The subjects was divided into two groups. The experimental group was 9 rabbits, treated with intraperitoneal administration of zoledronate(0.06mg/kg) once per week for 3 weeks. In control group, same procedure was applied but administerd saline instead of zoledronate. After 4 weeks, surgical operation under local anesthesia (ketamine 3.0cc, xylazine 1.0cc) was done. At postoperative 1, 2, 4, 8 weeks later, each rabbits were sacrificed and removed the bone grafted area. Gross, radiologic and histopathologic exminations of bone grafted area were performed. Result : There were no conspicuous differences of radiological findings between experimental and control groups in any experimental weeks. In experimental group, new bone formation appeared earlier than control group at 1 week after operation, and maturation of bony tissue were more conspicuous at 2 and 4 weeks after operation, compared with control group. In 8 weeks after operation, similar microscopic findings were noted in both groups. Conclusion : In the bisphosphonate-treated rabbits, new bone formation in the bone grafted area appeared earlier and bony maturation was more concpicuous, even though there were no significant differences of gross and radiological findings. These findings suggest that bisphosphonate might be promotive effect in the healing process in early stage after administration.