• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.303-320
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• 1994

Current acceptable methods For promotin gperiodontal regeneration are base on removal of diseased soft tissue, root treatment, guided tissue regeneration, inteoduction of new graft materials and biological mediators. Platelet-derived growth factor(PDGF) is one of polypeptide growth factor. PDGF has been reported as a biological mediator which regulates activities of wound healing process including the cell proliferation, migration and metabolism. The purposes of this study is to evaluate the effects of PDGF-AA, BB on the periodontal ligament cells to use as a regeneration promoting agent of periodontal tissue. Human periodontal ligament cells were prepared from the first premolar tooth extracted for the orthodontic treatment and were cultured in DMEM/10% FBS at the $37^{\circ}C$, 5% $CO_2$ incubator. Author measured the DNA synthesis, total protein, collagen and noncollagenous protein synthesis and alkaline phosphatase activity according to the concentration of PDGF-AA and BB(0, 0.1, 1, 10, 100ng/ml). The results were as follows : The DNA synthetic activity was increased dose dependently by PDGF-AA and BB. The maximum mitogenic effect was at the 100ng/ml of PDGF-AA and 10ng/ml of PDGF-BB. The total protein, collagen and noncollagen systhesis was increased dose dependently by PDGF-AA and BB. The % of collagen was slightly decresed according to the concentration of PDGF-AA and BB. The effect of PDGF-AA and BB were not specific for collagen synthesis since it also increased noncollagenous protein synthesis. The effect of PDGF-AA and BB on alkaline phosphatase activity did not show any significant, meanwhile the alkaline phosphatase activity of 14 days group showed significnat increase. In conclusion, PDGF-AA and BB may have important roles in stimulation of DNA synthesis in human periodontal ligament cells, which means an increase in collagen-synthesizing cells, and may be useful for clinical application in periodontal regenerative procedures.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.652-663
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• 1999

Craniosynostosis, the premature fusion of cranial sutures, presumably involves disturbance of the interactions between different tissues within the cranial sutures. Interestingly, point mutaions in the genes encoding for the fibroblast growth factor receptors(FGFRs), especially FGFR2, cause various types of human craniosynostosis syndromes. To elucidate the function of these genes in the early morphogenesis of mouse cranial sutures, we first analyzed by in situ hybridization the expression of FGFR2(BEK) and osteopontin, an early marker of osteogenic differentiation, in the sagittal suture of calvaria during embryonic(E15-E18) and postnatal stage(P1-P3). FGFR2(BEK) was intensely expressed in the osteogenic fronts, whose cells undergo differentiation into osteoprogenitor cells that ultimately lay down the bone matrix. Osteopontin was expressed throughout the parietal bones excluding the osteogenic fronts, the periphery of the parietal bones. To further examine the role of FGF-mediated FGFR signaling in cranial suture, we did in vitro experiments in E15.5 mouse calvarial explants. Interestingly, implantation of FGF2 soaked beads onto both the osteogenic fronts and mid-mesenchyme of sagittal suture after 36 hours organ culture resulted in the increase of the tissue thickness and cell number around FGF2 beads, moreover FGF4-soaked beads implanted onto the osteogenic fronts stimulated suture closure due to an accelerated bone growth, compared to FGF4 beads placed onto mid-mesenchyme of sagittal suture and BSA control beads. In addition FGF2 induced the ectopic expression of osteopontin and Msx1 genes. Taken together, these data indicate that FGF-mediated FGFR signaling has a important role in regulating the cranial bone growth and maintenance of cranial suture, and suggest that FGF-mediated FGFR signaling is involved in regulating the balance between the cell proliferation and differentiation through inducing the expression of osteopontin and Msx1 genes.

• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.219-237
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• 1994

The ultimate goal of clinical periodontal therapy is to achieve regeneration of a healthy connective tissue reattachment. Conventional therapy including scaling, root planing, gingival curettage, gingivectomy and flap procedures of various types results primarily in repair rather than regeneration of the periodontium. In order for periodontal regeneration to occur, progenitor periodontal ligament cells must migrate to the denuded root surface, attach to it, proliferate and mature into an organized and functional fibrous attachment apparatus. Polypeptide growth factors belong to a class of potent biologic mediators which regulate cell differentiation, proliferation, migration and metabolism. Insulin-like growth factor-I (IGF- I ) of these factors appear to have an important role in periodontal wound healing and bone formation. The purpose of this study is to evaluate the effects of IGF- I on the periodontal ligament cells to use as a regeneration promoting agent of periodontal tissue. Human periodontal ligament cells were obtained from periodontal tissue explants culture of the first premolar tooth extracted for the orthodontic treatment. Cells were cultured in Dulbecco's modified Eagle medium(DMEM) with 10% fetal bovine serum. Fourth to seventh passage cells were plated in 24 well tissue culture plates and medium changed to serum-free medium prior to addition of growth factors. Cell proliferation was measured by the incorporation of $[^3H]-thymidine$ into DNA, Protein synthesis was determined by measurement of $[^3H]-proline$ incorporation into collagenase-digestible protein(CDP) and noncollagenous protein(NCP) according to the method of Peterkofsky and Diegelmann (1971), And alkaline phosphatase activity was measured as one parameter of osteoblastic differentiation. The results were as follows : The DNA synthetic activity was increased in a dose-dependent manner with IGF- I except for 0.1ng/ml concentration of IGF- I At the concentration of 10, 100ng/ml, IGF- I significantly increased the DNA synthetic activity(P<0.05) The total protein, collagen and noncollagen synthesis was increased in a dose-dependent manner with IGF- I except for 0.1ng/ml concentration of IGF- I. At the concentration of 1, 10, 100ng/ml, IGF- I significantly increased the total protein, collagen and noncollagen synthesis activity(P<0.95, P<0.001). The % of collagen was not effected according to the concentration of IGF- I. The alkaline phosphatase activity was increased in a dose-, time-dependent manner with IGF- I (10, 100ng/ml). In conclusions, the present study shows that IGF- I has a potentiality to enhance the DNA synthesis of periodontal ligament cells with including the increase of the total protein and collagen synthetic activity. The use of IGF- I to mediate biological stimulation of periodontal ligament cells shows promise for future therapeutic applications.

• Journal of Life Science
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• v.28 no.9
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• pp.1030-1041
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• 2018

Abiotic stresses limit the growth and productivity of plants. Cellular adaptation to abiotic stresses requires coordinated regulation in gene expression directed by complex mechanisms. This study used the activation tagging system to identify novel salt stress-responsive genes. The study selected 9 activation tagging lines that showed salt stress-tolerant phenotypes during their germination stages. Thermal asymmetric interlaced-PCR (TAIL-PCR) was used to identify the T-DNA tagging sites on the Arabidopsis genome in selected activation tagging lines, including AT7508, AT7512, AT7527, AT7544, AT7548, and AT7556. RT-PCR analysis showed that ClpC2/HSP93-III (At3g48870), plant thionin family (At2g20605), anti-muellerian hormone type-2 receptor (At3g50685), vacuolar iron transporter family protein (At4g27870), and microtubule-associated protein (At5g16730) were activated in AT7508, AT7512, AT7527, AT7544, and AT7556, respectively. Interestingly, in AT7548, both the genes adjacent to the T-DNA insertion site were activated: Arabinogalactan protein 13 (AGP13) (At4g26320) and F-box/RNI-like/FBD-like domains-containing protein (At4g26340). All of the seven genes were newly identified as salt stress-responsive genes from this study. Among them, the expression of ClpC2/HSP93-III, AGP13, F-box/RNI-like/FBD-like domains-containing protein gene, and microtubule-associated protein gene were increased under salt-stress condition. In addition, AT7508, AT7527, and AT7544 were more tolerant to salt stress than wild type at seedling development stage, functionally validating the screening results of the activation tagging lines. Taken together, our results demonstrate that the activation tagging system is useful for identifying novel stress-responsive genes.

• Journal of Mushroom
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• v.9 no.4
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• pp.155-160
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• 2011

Changes of fruiting body yield and morphology according to growing temperatures in Pleurotus strains were investigated. In this study, twelve commercial strains divided into low, medium and high temperature groups were tested. On the basis of fruiting body yield, they showed best in their own temperature properties. On the other hand, they didn't have any fixed tendency to growing temperatures on morphological characteristics. Thicknesses of pilei were best at $10^{\circ}C$, having nothing to do with strains. Lengths of stipes were increased with the progress of cultivation temperatures in five strains including 'Sambok'. The other strains showed differences on this trait. Thicknesses of stipes were decreased with the progress of cultivation temperatures in other strains excepting 'Sambok and ASI2029'. Days for harvest were extended as temperature decreased, even though the shortest days were different according to strains. Sometimes there were abnormal shapes of fruiting bodies in response to temperatures in some strains. In 'Suhan-1', white cilia fully covered onto the surface of pilei were observed macroscopically at the early stage and then disappeared or remained a little later at $10^{\circ}C$ cultivation. In 'Chunchu-2', their stipes were twisted and bent over $20^{\circ}C$ cultivation.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.3
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• pp.489-494
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• 2003

Odontomas are the common type of odontogenic tumors and generally they are asymptomatic, depending upon size, location and their limited growth potential. they are rarely diagnosed before the second decade of life, and the frequently lead to impaction or delayed eruption of permanent teeth. Odontomas are classified of compound as compound or complex by morphology. Complex odontomas are unorganized masses of odontogenic tissues, morphologically not resembling the teeth, account for approximately 25 percent of all odontomas, 22 percent of odontogenic tumor of the jaws, and have a predilection for the posterior mandible in males. The etiology of odontomas is unknown, although local trauma, infection, and genetic factors have been suggested. Usually, treatment of odontoma is conservative sugical removal and their is little probability of recurrence. This paper describes two cases of complex odontomas diagnosed in children due to impaction of maxillary first molar in all cases, the surgical excision of the lesions was performed. Follow-up after 2 years, showed spontaneous eruption of the first permanent molar to the occlusal plane.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.12 s.148
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• pp.1527-1534
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• 2005

In order to clarify the characteristics of the thermo-physiological responses of the child and to understand the influence of the country where the child has grown up on the responses, the thermo-physiological responses of the Japanese children(J group) and the Korean children(K group) were examined. The subject wearing shorts was exposed first to a thermo neutral room$(Ta=28.5^{\circ}C)$ for 1 hour, then transferred to a cold$(Ta=22^{\circ}C)$ or a hot$(Ta=37^{\circ}C)$ room for 1 hour. The experiment was done in the climate chamber of Bunka Women's University in the summer of 1997 for Japan, and in the climate chamber in the Keimyung University in the summer of 1998 for Korea. The subjects consisted of 5 boys and 5 girls aged 7-9 years in Japan and 4 boys and 4 girls aged 7-9 years in Korea. As a result: 1) The rectal temperature increased slightly with a rise in air temperature. K group showed a slightly higher rectal temperature. 2) The skin temperature of the hand and foot decreased conspicuously during cold exposure. It was more in the K group than in the J group. 3) Relative local sweat rates were similar in the two groups at $22^{\circ}C\;and\;28.5^{\circ}C$, while they were considerably different at $37^{\circ}C$. Even perspiration was observed over the whole body in the J group but the perspiration was large in the trunk and low in the extremity in the K group. 4) The heart rate was higher in the J group than in the K group but it increased with the rise of the air temperature in both groups.

• Journal of Life Science
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• v.24 no.2
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• pp.196-208
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• 2014

During the life cycle of plants, water deficit leads to an adverse effect on its growth and development. To increase the productivity of crops, overcoming such drought stress is one of the most important issues in the field of plant study. Among plant hormones, the phytohormone, abscisic acid (ABA) plays a crucial role in eliciting resistance to drought stress as well as in multiple developmental processes, such as seed germination, stomatal closure, and seedling growth. Therefore, further understanding of the ABA-mediated signal transduction pathway in plants is an effective strategy to generate drought-tolerant plants. Posttranslational modification, such as phosphorylation and ubiquitination, is an efficient mechanism for plants to acquire quick adaptation against environmental stress conditions since this process directly affects pre-existing signaling components by modulating protein activity and stability. Here, recent reports on ABA signaling are reviewed, especially focusing on ABA transport, perception, signaling, and posttranslational modification in ABA-mediated cellular responses. Also, we present future prospects on how the control of such a mechanism can be applied to generate useful agricultural crops.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.189-196
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• 1992

Pre-surgical and post-surgical change in adult cleft lip and palate patient following Le Fort I advancement osteotomy combined with bone graft was evaluated clinically and cephalometically. We obtained a successful function and esthetic improvement. The bone graft of alveolo-palatal clefts provides a stable bone support to the adjacent teeth of the cleft area, and well union of adjacent bone tissue, the closure of oronasal fistula and improvement of speech problem. Le Fort I osteotomy following the ostectomy of nasal septum for advancement of the maxilla was obtained relative improvement of esthetics and functional occlusion. 1. The orthodontic correction was required before and after surgery. 2. In this case, there was a limited range of anterior advancement of the Premaxillary-segment due to the scar tissue. 3. After 8 months of operation, we could show the new bone deposition on the cleft site in dental radiograph and then the prosthetic treatement to the missing teeth was done.

• Applied Biological Chemistry
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• v.41 no.1
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• pp.47-52
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• 1998

3-Hydroxy-3-methylglutaryl-CoA reductase (HMGR) catalyzes the conversion of HMG-CoA to mevalonic acid, the first intermediate of isoprenoid biosynthetic pathway in plants. The enzyme was solubilized with 0.4% Brij (polyoxyethylene ether) W-1 from a microsomal fraction of etiolated rice seedlings (Oryza sativa L.) in which its maximal activity was observed on the fourth day after germination. HMGR was purified to near homogeneity by employing $(NH_4)_2SO_4$ fractionation plus chromatographic procedures including DEAE-Sephadex A-50 and HMG-CoA-hexane-agarose affinity column. The size of the purified enzyme was estimated to be 55 kDa when judged by SDS-PAGE analysis with silver staining method. The apparent $K_m$ and $V_{max}$ values for HMG-CoA were determined to be $180\;{\mu}M$ and 107 pmol/min/mg, and those for NADPH were $810\;{\mu}M$ and 32.1 pmol/min/mg, respectively.