• Current Optics and Photonics
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• v.1 no.4
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• pp.412-420
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• 2017

Multinucleated bone resorptive osteoclasts differentiate from bone marrow-derived monocyte/macrophage precursor cells. During osteoclast differentiation, mononuclear pre-osteoclasts change their morphology and biochemical characteristics. In this study, Raman spectroscopy with multivariate techniques such as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were used to extract biochemical information related to various cellular events during osteoclastogenesis. This technique allowed for label-free and noninvasive monitoring of differentiating cells, and clearly discriminated four different time points during osteoclast differentiation. The Raman band intensity showed significant time-dependent changes that increased up to day 4. The results of Raman spectroscopy agreed with results from atomic force microscopy (AFM) and tartrate-resistant acid phosphatase (TRAP) staining, a conventional biological assay. Under AFM, normal spindle-like mononuclear pre-osteoclasts became round and smaller at day 2 after treatment with a receptor activator of nuclear $factor-{\kappa}B$ ligand and they formed multinucleated giant cells at day 4. Thus, Raman spectroscopy, in combination with PCA-LDA, may be useful for noninvasive label-free quality assessment of cell status during osteoclast differentiation, enabling more efficient optimization of the bioprocesses.

• Molecules and Cells
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• v.40 no.8
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• pp.550-557
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• 2017

The periodontal ligament (PDL) is the connective tissue between tooth root and alveolar bone containing mesenchymal stem cells (MSC). It has been suggested that human periodontal ligament stem cells (hPDLSCs) differentiate into osteo/cementoblast and ligament progenitor cells. The periodontitis is a representative oral disease where the PDL tissue is collapsed, and regeneration of this tissue is important in periodontitis therapy. Fibroblast growth factor-2 (FGF-2) stimulates proliferation and differentiation of fibroblastic MSCs into various cell lineages. We evaluated the dose efficacy of FGF-2 for cytodifferentiation of hPDLSCs into ligament progenitor. The fibrous morphology was highly stimulated even at low FGF-2 concentrations, and the expression of teno/ligamentogenic markers, scleraxis and tenomodulin in hPDLSCs increased in a dose dependent manner of FGF-2. In contrast, expression of the osteo/cementogenic markers decreased, suggesting that FGF-2 might induce and maintain the ligamentogenic potential of hPDLSCs. Although the stimulation of tenocytic maturation by $TGF-{\beta}1$ was diminished by FGF-2, the inhibition of the expression of early ligamentogenic marker by $TGF-{\beta}1$ was redeemed by FGF-2 treatment. The stimulating effect of BMPs on osteo/cementogenesis was apparently suppressed by FGF-2. These results indicate that FGF-2 predominantly differentiates the hPDLSCs into teno/ligamentogenesis, and has an antagonistic effect on the hard tissue differentiation induced by BMP-2 and BMP-4.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.236-239
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• 2005

This study investigated the effect of ovariectomy (OVX) on the rat bone fur long term (22 weeks). In previous researches, there were many studies for morphology of OVX-induced osteoporotic bones based on micro-Computed Tomography (micro-CT). However, there were few studies fpr detecting and tracking changes of mechanical characteristics in the lumbar vertebrae of OVX rat fur long-term. For this study, one female Sprague-Dawley rat was used: an OVX rat. The 4th lumbar of the OVX rat was utilized as a specimen. Morphological characteristics could be investigated fur the lumbar vertebrae in an OVX rat by using in-vivo Micro-CT. An OVX rat was scanned at week 0 (just before surgery), at week 4, at week 8, at week 16 and at week 22 after surgery. Micro finite element $({\mu}FE)$ analysis was used to investigate mechanical characteristics in the lumbar vertebrae for an OVX rat.

• Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.294-305
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• 2024

Tomini Bay in Gorontalo offers significant potential for amphidromous goby-fry, a group of fish found in at least five estuaries in the area, namely Bone-Bolango, Paguyaman, Bilungala, Tombulilato, and Taludaa Estuaries. Preliminary results were limited to only two locations in estuarine waters, namely the Bone-Bolango and Paguyaman rivers. Further exploration of goby-fry species in various locations within Tomini Bay is essential to enhance knowledge about the abundance and aid conservation efforts. Therefore, this study identified the goby-fry species and created their distribution map in the waters of Tomini Bay Gorontalo. The samples used were obtained from daily catches of fishermen in the five estuaries during the recruitment period from February to September 2022. These samples were categorized based on their morphological similarities and specific melanophore patterns. Distinct groups with different melanophore patterns from those previously reported were identified as newly recorded species, photographed, and described in terms of their morphology. Furthermore, two specimens from each newly recorded species underwent molecular identification using the cytochrome oxidase subunit 1 (COI) gene for DNA amplification and were analyzed through the Basic Local Alignment Search Tool (BLAST) method. The phylogenetic tree was constructed using the Maximum Likelihood Method. The results showed the existence of nongoby-fry species caught together with goby fry school. A total of 75,881 goby-fry and 1,687 nongoby-fry were successfully collected. Among the goby-fry species, 13 were identified, including three new records, namely Eleotris fusca (Forster, 1801), Sicyopterus microcephalus (Bleeker, 1855), and Sicyopus zosterophorus (Bleeker, 1856). This study also documented the existence of nongoby-fry species, namely Anguilla celebesensis (Kaup, 1856), Moringua microchir (Bleeker, 1853), and Microphis leiaspis (Bleeker, 1854). It significantly contributed to the understanding of fish biodiversity in Tomini Bay.

• Imaging Science in Dentistry
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• v.32 no.3
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• pp.167-173
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• 2002

Purpose : To evaluate clinical and radiographic differential diagnosis between ameloblastoma and odontogenic keratocyst (OKC) using clinical data, plain radiographs, and CT. Materials and Methods: 25 cases of ameloblastoma and 44 cases of OKC diagnosed in biopsy, were selected from the files stored in Department of Oral and Maxillofacial Radiology, Seoul National University Dental Hospital from 1999 to 2001, and evaluated using following criteria: sex and age, location, shape, border to normal bone tissue, effect to adjacent tissues, homogeneity in the lumen of the lesion, response of the cortical bone, long-to-short length (LIS) ratio of the lesion, and expansion angle of the cortex. Results: Ameloblastoma and OKC were seen most frequently in third decades and no statistical significance was noted between both sexes. Ameloblastoma occurred most frequently in mandibular angle and ramus area (68%) and OKC at the maxillary molar (34.1 %), and mandibular angle and ramus area (43.2%). The root resorption of the adjacent teeth, mandibular canal displacement, and the impaction of teeth were seen more frequently in ameloblastoma than in OKC. The LIS ratio measured in CT was largest in maxillary OKC cases, followed by mandibular ameloblastoma, and mandibular OKC (1.2, 1.8 and 2.4 respectively). The expansion angle of the cortex shows a statistically significant difference between ameloblastoma (48.8°) and OKC (31.5°). Conclusion : The numeric morphology (LIS ratio) and expansion angle of the cortical bone of the lesion measured in computed tomography can be used to differentiate the ameloblastoma and odontogenic keratocyst.

• Imaging Science in Dentistry
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• v.34 no.1
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• pp.25-30
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• 2004

Purpose: Several panoramic indices have been suggested to assess bone quality from the morphology and width of mandibular cortex on panoramic radiography. The purpose of this study was to compare dental implant failure group with control group in panoramic mandibular index (PMI), mandibular cortical index (MCI), and gonion index (GI) and to determine the effect of these panoramic indices on dental implant failure. Materials and Methods: A case-control study was designed. Test group (n=42) consisted of the patients who had their implants extracted because of peri-implantitis. Control group (n=139) consisted of the patients who retained their implants over one year without any pathologic changes and had been followed up periodically. They had dental implants installed in their mandibles without bone augmentation surgery from 1991 to 2001. The following measures were collected for each patients: 1) PMI, MCI, and GI were measured twice at one-week interval on preoperative panoramic views; and 2) age, sex, implant length, implant type, installed location, occluding dentition state, and complication were investigated from the chart record. Results: The PMI showed moderate level of repeatability. The intra-observer agreement of MCI and GI were good. There was statistically significant difference in PMI between two groups. There were significant different patterns of distribution of MCI and GI between two groups. Among the panoramic indices, PMI and MCI showed significant correlation with dental implant failure. Conclusion: Panoramic indices can be used as reference data in estimating bone quality of edentulous patients who are to have implants installed in their mandibles.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.2
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• pp.175-191
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• 2004

Statement of problem: Platelet-rich plasma(PRP) is well known to be very effective method to stimulate and accelerate the healing of bone and soft tissue. However, there are few reports which deal with the mechanisms of the PRP on the activation of the osteoblasts. Purpose: This study was aimed to investigate the effect of growth factors in PRP on the activity of osteoblasts. Material and method: To evaluate the effect on human, human osteoblast cell line was cultured. PRP was extracted from the blood of a healthy volunteer. Using the recombinant growth factors of PDGF, $TGFT-\beta$, IGF-1, bFGF which are mainly found at bone matrix and their neutralizing antibody, the effect of PRP on the attachment and proliferation of osteoblasts was evaluated. To evaluate the autocrine and paracrine effects, conditioned media(CM) of PRP was made and compared with PRP. By the western blot analysis, the expression of growth factors in PRP, CM was examined. Cell morphology was compared by the light microscope. Results : 1) The effects of CM on osteoblast were similar to the effects of PRP. 2) PRP, CM, recombinant $TGF-\beta$, bFGF, IGF-1 showed significantly higher cellular attachment than control(p<0.05) in the cell attachment assay. In the cell proliferation assay, PRP, CM, recombinant $TGF-\beta$, IGF-1, bFGF, PDGF increased significantly cell proliferation(p<0.01). Among the recombinant growth factors, IGF-1 showed the highest cellular attachment and proliferation. 3) In the western blot assay, bFGF, IGF-1, PDGF weve equally expressed in PRP and CM. 4) The attachment of osteoblast cell decreased significantly after the addition of neutralizing antibody against $TGF-\beta$, IGF-1(p<0.05). In the cell proliferation assay, the addition of neutralizing antibody against $TGF-\beta$, bFGF, PDGF, IGF-1 decreased significantly the cellular proliferation(p<0.05). The amount of decreasing in the cell attachment and proliferation is the highest in at-lGF-1. 5) The cells in control group were flattened and elongated with a few cellular processes in the a light microscope. But, the cells appeared as spherical, plump cells with well developed cellular processes in experimental groups. The cells in PRP and CM had more prominent developed features than recombinant growth factor groups. Conclusions : These findings imply that PRP maximize the cellular activity in early healing period using the synergistic effect, autocrine, paracrine effects of growth factors and increase the rate and degree of bone formation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.562-573
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• 1997

Comparative osteology of Chromis notata, C. analis and C. fumea was studied based on the samples collected from the Korean waters. The three species are distinguished by the shape of cranium, visceral skeleton, vertebra and caudal skeleton. Chromis notata has a glossohyal which is slightly curved in shape while two other species are deeply curved. C. analis has three spiniform procurrent caudal rays while others have two. C. fumes could be distinguished easily by the shape of preopercle which is serrate in posterior margin. This investigator reveals following bones as new taxonomic criteria for the genus Chromis in Korea. In cranium, height of supraoccipital, height of process of parasphenoid and anterior margin of basisphenoid, in visceral skeleton, presence of fine papilla-like process at the surface of preopercular sensory canal, in orbital bone, width of preorbital, in hyoid arch, shape of glossohyal, union state between lower hypohyal and ceratohyal and union state between ceratohyal and epihyal, in shoulder girdle bone, dorsal margin of posttemporal, width of upper postclavicle, posterior end of lower postclavicle and posterior margin of first actinost bone, in vertebrae, beginning point of parapophysis, in caudal skeleton, upper shape of second neural spine of pleural centrum.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.5
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• pp.446-454
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• 2000

Condylar process of mandible is an important and fuctionally versatile part of the mandible. There were quite large amount of investigations on the functional and anatomical adaptation of the temporomandibular joint(TMJ) to the surrounding tissues. But controversies on the mechanism of functional adaptation of the joint still exist. In this research, we investigated changes in the TMJ by the lateral deviation of the maxillary incisor to shift the mandible right, and bone the undecalcified microscopic sections with fluorescent microscope and von Kossa staining with bright field microscope. Results were as follows: 1. Lateral deviation rendered shifting and tilting of the mandible, There were, compressions in the right joint and opening of the left joint space at early stage. At the same time, both condyles shifted slightly to anterior. 2. After $2{\sim}4$ weeks, left condyle showed anterior displacement and compressions in the joint space. Right condyle showed only slight shift to the anterior. 3. Regardless of the direction of the lateral shift, anterior bite plate compressed both condyle heads until 2 weeks. 4. There are bone resorptions in the anterior aspect of the condyle head and apposition of posterior border. Bone remodeling were observed between 3 and 4 weeks. 5. After 8 weeks of the experiment, there were little differences in condylar morphology between experimental and control group, though slight shifting and compression were still present in the experimental group. Lateral deviation of mandible evoked active remodeling of the TMJ until functional and anatomical reconstruction of TMJ position was achieved.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.603-613
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• 1995

The purpose of this investigation was to evaluate on the biodegradability, biocompatibility and tissue regenerative capacity of synthetic bioabsorbable membranes in beagle dogs. For animal study, 9 adult beagle dogs were used to examination, on the surgical implantation of membranes and histological analysis. In each animal, the 3rd and 4th premolars of the both sides of the mandible were selected as test teeth. Two types of bioresorbable membranes including "Guidor membrane", "S-membranes" were used to examining for biological activity, and also Gore-tex membranes was used for positive control. Surgically created defects were made in 2 premolars of both sides of the mandible at $3{\times}4mm^2$ in size and tested membranes were implanted in the defected area. A plaque control regimen was instituted with daily tooth brushing with a 0.1% chlorhexidine digluconate during experimental periods. All the experimental animals were sacrificed after 2, 4, and 8 weeks from surgery and undecalcified slides were prepared using the "sawing and grinding" technique described by Donath and Breuner". In biodegradability, all the membranes were started their biodegradation from two weeks after implantation and gradually demolished of their frame morphology from eight weeks. However, demolition of membranes in 8 weeks after implantation was highest in Guidor membranes and followed by S-membranes. Biocompatibilityof two kinds of biodegradable membranes including Guidor and S-mambrane were shown to be well tolerated to the surrounding tissue, and were minimal accumulation of inflammatory cell infiltration around the implanted membranes to compare with Gore-tex membrane. Regeneration of defected alveolar bone was initiated from two weeks of membrane implantation and new bone formation was gradually increased from that time. However, pattern of new bone formation on the defected areas of two kinds of biodegrable membranes was almost similar and quite competitive comparing with Gore-tex membrane. These results implicate that bioresorbable membranes should be highly useful tool for guided tissue regeneration of periodontal defects.