• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.4
• /
• pp.509-515
• /
• 2002

Copper deficiency was induced in eight male buffalo calves by adding molybdenum (30 ppm wet basis) to their diet. Copper status was monitored from the liver copper concentration and a level below 30 ppm (DM basis) was considered as deficient. Haemoglobin, haematocrit, total and differential leucocyte numbers were determined. The functions of peripheral neutrophils were assessed by in vitro phagocytosis and killing of Staphylococcus aureus. The effect of molybdenum induced copper deficiency on bone marrow was monitored. The mean total leucocyte count was unaffected whereas a significant fall in neutrophil count coincided with the fall in hepatic copper level to $23.9{\pm}2.69$ ppm. Reduced blood neutrophil numbers was not accompanied by any change in the proportion of different neutrophil precursor cells in bone marrow. It was hypothesised that buffalo calves were more tolerant to dietary molybdenum excess than cattle. It was concluded that neutropenia in molybdenum induced copper deficiency occurred without any effect on their synthesis and maturation process. Bone marrow studies in healthy calves revealed higher percentage of neutrophilic myelocytes and metamyelocytes as compared to cattle.

• Clinical and Experimental Pediatrics
• /
• v.53 no.3
• /
• pp.286-293
• /
• 2010

Peak bone mass is established predominately during childhood and adolescence. It is an important determinant of future resistance to osteoporosis and fractures to gain bone mass during growth. The issue of low bone density in children and adolescents has recently attracted much attention and the use of pediatric dual-energy X-ray absorptiometry (DXA) is increasing. The process of interpretation of pediatric DXA results is different from that of adults because normal bone mineral density (BMD) of children varies by age, body size, pubertal stage, skeletal maturation, sex, and ethnicity. Thus, an appropriate normal BMD Z-score reference value with Z-score should be used to detect and manage low BMD. Z-scores below -2.0 are generally considered a low BMD to pediatrician even though diagnoses of osteoporosis in children and adolescents are usually only made in the presence of at least one fragility fracture. This article will review the basic knowledge and practical guidelines on pediatric DXA based on the International Society for Clinical Densitometry (ISCD) Pediatric Official Positions. Also discussed are the characteristics of normal Korean children and adolescents with respect to BMD development. The objective of this review is to help pediatricians to understand when DXA will be useful and how to interpret pediatric DXA reports in the clinical practice for management of children with the potential to develop osteoporosis in adulthood.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.27 no.1
• /
• pp.1-8
• /
• 2001

This study was designed to localize the distribution of basic fibroblast growth factor(bFGF) in the developing rat condylar region and to elucidate the associated function of bFGF in the condyle development. The condyles of temporomandibular joint of Sprague-Dawley rats (27g of weight) were used. The tissues were examined with electron microscope and immunohistochemical method. The results were as follows: 1. The developing condylar region are divided in to 5 zones apparently: proliferative, maturation, hypertrophic, calcifying, and ossification zones. 2. The cells in the proliferative zone are condensed and have under-developed cell organells in the cytoplasm. This zone shows a strong immunoreactivity of bFGF. 3. The cells in the maturation zone are typical chondroblasts showing well-developed cell organells and round nucleus. The cartilaginous matrix does not show the immunoreactivity of bFGF, while the chondroblasts show the immunoreactivity. 4. The cells in the hypertrophic zone show hypertrophic change having the degenerated cell organelles and small nucleus. There are no immunoreactivity of bFGF in this zone except the nucleus and endoplasmic region showing mild immunoreactivity. 5, The cells in the calcifying zone show hypertrophic change and cell organelles are disappeared. The cells are surrounded by the calcified cartilaginous matrix. There are no immunoreactivity of bFGF in this zone except the endoplasmic region showing mild immunoreactivity. 6. In the zone of bone formation, chondroblasts are disappeared. Newly differentiated osteoblasts secreting osteoid around the calcified cartilaginous matrix. The bone marrow shows the immunoreactivity of bFGF, while the bone matrix does not show the immunoreactivity of bFGF.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.36 no.2
• /
• pp.37-49
• /
• 2014

Purpose: This study compares the bone formation ability of tricalcium phosphate (TCP) with and without recombinant human bone morphogenetic protein-2 (rhBMP-2) and assesses TCP as a carrier of rhBMP-2. Methods: Bilateral round defects (diameter: 8.0 mm) were formed in the cranium of eight New Zealand white rabbits. The defects were grafted with TCP only (control group) or with rhBMP-2-coated TCP (experimental group). The animals were sacrificed at 1st week, 2nd week, 4th week, and 8th week postoperatively; two rabbits sacrificed each time. The skulls were harvested and subjected to radiographic and histological examination. Results: Radiologic evaluation showed faster bone remodeling in the experimental group than in the control group. Histologic evaluation (H&E, Masson's trichrome stain) showed rapid bone formation, remodeling and calcification in the 1st and 2nd week in the experimental group. Immunohistochemical evaluation showed higher expression rate of osteoprotegerin, receptor activator of nuclear factor ${\kappa}B$ ligand, and receptor activator of nuclear factor ${\kappa}B$ in the experimental group at the 1st and 2nd week than in the control group. Conclusion: rhBMP-2 coated TCP resulted in rapid bone formation, remodeling, and calcification due to rhBMP-2's osteogenic effect. TCP performed properly as a carrier for rhBMP-2. Thus, the use of an rhBMP-2 coating on TCP had a synergic effect on bone healing and, especially, bone remodeling and maturation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.28 no.3
• /
• pp.205-215
• /
• 2002

The purpose of this study was to evaluate the tissue response in various bone grafting materials, especially xenogenous bone materials in vivo, compare of bone formation capacity of various bone grafting materials on rat skull defects and evaluate the effect of Hyaluronic acid on healing of human Demineralized Freezed Dried Bone allogenous graft (DFDBA) materials in rat calvarial defects. 30 Sprague-Dawly rats were divided into 4 groups. $7{\times}7mm$ size bony defect were artificially prepared in the calvaria (both parietal bone) of all 30 rats and follwed group grafting of autogenous bone graft on right side and allogenic DFDBA on left side bone graft (rat DFDB) in 15 control group, but in 15 experimental group, xenograft (human DFDB) on left side, hyaluronic acid treated with xenograft on right side. Sequential sacrifices was performed at 1, 2, 4, 6, 8 weeks of experiment. These specimens were stained with H&E and MT stain, and then histologic analysis under light microscope was carried out. There were inflammatory reaction in all graft material during early stage. Autogenous and Allogenous DFDBA graft group observed inflammatory reaction at 1 week. Xenograft group persistant inflammatory reaction until 4 weeks, but in HA treated xenograft group inflammatory reaction was decreased at 2 weeks. Osteoblastic activity in control group was begun at 2 week, xenograft group was delayed at 6 weeks, however HA treated xenograft group was begun at 4 weeks. At 2 week, mild osteoclastic activity were observed in all xenograft group not in concerned to HA, but there was no difference each group after 4 weeks. There are most activated angiogenesis around graft mateirals in xenograft group at 2 weeks, but in HA treated xenograft group, decreased angiogenesis was observed at same time. Bone formation and bone maturation of xenograft group, there was no difference in HA treatment, was less than control group. Fibrosis around xenograft materials were observed until 6 weeks, there was no difference between xenograft and HA treated groups.

• Journal of Periodontal and Implant Science
• /
• v.23 no.3
• /
• pp.461-474
• /
• 1993

This study was performed to estimate the effect of plaque control on the progress of the repair pattern of the alveolar bone surface after bone surgery. In this experiment six mongrel dogs were used, four of them were as experimental group and others were as control. In the case of experimental group, dental floss ligature was tied over the neck of crown for permiting of plaque accumulation during one week before surgery and oral hygiene procedures were not performed. In control group, all the surgical intervention was done as same procedure with experimental except oral hygiene program. After surgery plaque was controlled during one week with using the chlorhexidine brushing. Animals were sacrificed at 1,2,4,6 weeks after osseous surgery. The results were as follows : 1. The alveolar bone defects were covered with regenerated epithelium at one week, matrix change of granulation tissue on subcutaneous area was observed, and new bone formation was initiated from the surface of the bone defects. 2. The connective tissue arrangement revealed more dense, new bone formation by osteoblasts was active at 2 weeks and proliferation of gingival epithelium and alveolar bone tissue were evident at 4 weeks, and almostly recovered to normal condition at 6 weeks. 3. In experimental group, inflammatory reaction was persistent in early stage and bone repair was delayed compared to control group. 4. In control group, matrix change of granulation tissue was initiated from one week, regeneration of gingival epithelium and maturation of subcutaneous conective tissue and new bone formation were evident at 2 weeks, so almost normal bone regeneration was observed at 4,6 weeks.

• BMB Reports
• /
• v.41 no.7
• /
• pp.485-494
• /
• 2008

The Wnt signaling network, which is composed of Wnt ligands, receptors, antagonists, and intracellular signaling molecules, has emerged as a powerful regulator of cell fate, proliferation, and function in multicellular organisms. Over the past two decades, the critical role of Wnt signaling in embryonic cartilage and bone development has been well established, and much has been learnt regarding the role of Wnt signaling in chondrogenesis and cartilage development. However, relatively little is known about the role of Wnt signaling in adult articular cartilage and degenerative cartilage tissue. This review will briefly summarize recent advances in Wnt regulation of chondrogenesis and hypertrophic maturation of chondrocytes, and review data concerning the role of Wnt signaling in the maintenance and degeneration of articular chondrocytes and cartilage.

• Journal of Veterinary Science
• /
• v.25 no.4
• /
• pp.49.1-49.15
• /
• 2024

Importance: Endochondral ossification plays an important role in skeletal development. Recent studies have suggested a link between increased intracellular reactive oxygen species (ROS) and skeletal disorders. Moreover, previous studies have revealed that increasing the levels of myeloperoxidase (MPO) and osteopontin (OPN) while inhibiting NADPH oxidase 4 (NOX4) can enhance bone growth. This investigation provides further evidence by showing a direct link between NOX4 and MPO, OPN in bone function. Objective: This study investigates NOX4, an enzyme producing hydrogen peroxide, in endochondral ossification and bone remodeling. NOX4's role in osteoblast formation and osteogenic signaling pathways is explored. Methods: Using NOX4-deficient (NOX4^-/-) and ovariectomized (OVX) mice, we identify NOX4's potential mediators in bone maturation. Results: NOX4^-/- mice displayed significant differences in bone mass and structure. Compared to the normal Control and OVX groups. Hematoxylin and eosin staining showed NOX4^-/- mice had the highest trabecular bone volume, while OVX had the lowest. Proteomic analysis revealed significantly elevated MPO and OPN levels in bone marrow-derived cells in NOX4^-/- mice. Immunohistochemistry confirmed increased MPO, OPN, and collagen II (COLII) near the epiphyseal plate. Collagen and chondrogenesis analysis supported enhanced bone development in NOX4^-/- mice. Conclusions and Relevance: Our results emphasize NOX4's significance in bone morphology, mesenchymal stem cell proteomics, immunohistochemistry, collagen levels, and chondrogenesis. NOX4 deficiency enhances bone development and endochondral ossification, potentially through increased MPO, OPN, and COLII expression. These findings suggest therapeutic implications for skeletal disorders.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.32 no.4
• /
• pp.317-326
• /
• 2006

Purpose : The aim of this study was to evaluate the effect of recombinant human bone morphogenetic protein-7 (rhBMP-7) injected on the rate of new-bone formation for distraction osteogenesis on dogs. Materials & Methods : Twelve adult dogs were randomly selected into two groups of six dogs on each. Unilateral osteotomies were performed on the body of the mandible and an intraoral distractor was mounted to the mandible on dogs. One group was treated with injection of rhBMP-7 and the other group served as the control. RhBMP-7 was administered on the day of surgery by single injection into the medullary bone at the osteotomy gap. Distraction was performed five days after osteotomy as a rate of 0.5 mm twice per day for 10 days. The animals were then sacrificed at 2, 4, and 8 weeks after completion of the distraction. Two dogs in each group, totaling four dogs, were killed at 2 weeks, 4 weeks, and 8 weeks after completion of distraction, respectively. The lengthened mandibles were harvested and processed for radiographic and histological examinations. In addition, immunohistochemical examination using osteocalcin expression was studied. Results : Radiographs showed accelerated regenerate ossification with maturation of new bone in the rhBMP-7 group comparing with the control group at the 4 weeks of the consolidation. There was no significant difference in the radiographic findings at the 2 weeks and 8 weeks of the consolidation period. Histological findings demonstrated increased bone healing pattern in the rhBMP-7-treated group during all observation period. The expression of osteocalcin immunoreactivity was hardly detected in the normal mandible of dog, but the expression was detected in all experimental rhBMP-7 treated specimens. There were also significant increasing in number of positive immunostaining cells and staining intensity of osteocalcin expression in the rhBMP-7 treated group compared with those of the control group on 2-weeks and 4-weeks. There was a significant decreasing in staining intenstiy of all both two groups on 8 weeks of consolidation period, but significant differences of immunostaining was not seen in two groups. Conclusions : A single injection of rhBMP-7 at the time of osteotomy may stimulate the rate of regenerate ossification and increase callus maturation during distraction osteogenesis. In addition, it may shorten the distraction osteogenesis procedure and decrease the prevalence of complications associated with mandibular distraction osteogenesis.

• Journal of Preventive Medicine and Public Health
• /
• v.37 no.1
• /
• pp.72-79
• /
• 2004

Objectives : This cross-sectional study aimed to quantify the relationship between the bone mineral density at the os calcis and the body mass composition in healthy children. Methods : The areal bone mineral density was measured at the os calcis with peripheral dual energy X-ray absorptiometry. The fat free mass, fat mass and percentage fat mass were measured using bioelectric impedance, in 237 Korean children, aged 9 to 12 years. The sexual maturity was determined by self assessment, using standardized series of the 5 Tanner stage drawings, accompanied by explanatory text. Results : From multiple linear regression models, adjusted for age, sexual maturity and height, the fat free mass was found to be the best predictor of the calcaneal bone mineral density in both sexes. About 15 and 20% variabilities were found in the calcaneal bone mineral densities of the boys and girls, respectively, which can be explained by the fat free mass. After weight adjustment, the percentage fat mass was negatively associated with the calcaneal bone mineral density in both sexes. Conclusions : The findings of this study suggest that the fat free mass, among the body compositions, is the major determinant of bone mineral density at the os calcis in Korean children aged 9 to 12 years. Obesity, defined as the percentage fat mass, is assumed to have a negative effect on the calcaneal bone density in children of the same weight.