• 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.

• Applied Microscopy
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• v.26 no.1
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• pp.79-93
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• 1996

The differentiation of nail matrix and fine structure of matrix cells were studied with light and electron microscope using specimens from nails of thumb finger in Korean fetuses 14 to 24 weeks old. Fetal nail matrix consisted of two horizontal layers, thicker ventral and thinner dorsal matrices, originating from invagination of epidermis in proximal nail field. Matrix being generally thicker in its distal region than the apex became gradually thickened with increase of the fetal age. Each matrix consisted of single layer of basal cells and multiple layers of squamous cells which are arranged close to and parallel to the central axis of the nail mairix. The process of keratinization of fetal nail matrix was noted to be occured concurrently in the ventral and dorsal matrices along the central axis of matrix toward distal and dorsal direction. Squamous cells became matured with accumulation of tonofilaments, increase of keratohyalin granules, discharge of membrane coating granules, and narrowing of intercellular spaces, thickening of plasma membrane and finally being transformed into horny cells of nail plate. Horny cells of nail plate filled with fibrous elements in the electron dense amorphous substance. These findings of keratinization process of fetal nail matrix appeared to be similar to those of keratinization in epidermis and inner root sheath of the hair. In the nail matrix, however, corresponding region to the keratogenous zone of growing hair follicle was not observed. Vacuolated squamous cells of nail matrix seen on light microscopy was considered to be artefactual product, but squamous cells with condensed small nuclei rarely found adjacent nail plate was considered to be one of the squamous cells with unknown function. Proximal end of nail plate was observed on dorsal surface of nail field distal to the proximal nail fold at 14 and 16 weeks old human embryos. Proximal prolongation of the proximal end of nail plate was occured with advancing fetal age and afterward 21 weeks nail plate invaded into nail matrix. Melanin granule containing cells and Merkel cells were present only on the basal layer of dorsal nail matirx.

• The Plant Pathology Journal
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• v.39 no.4
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• pp.309-318
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• 2023

Huanglongbing (HLB) is one of the most destructive diseases in citrus, which imperils the sustainability of citriculture worldwide. The presumed causal agent of HLB, 'Candidatus Liberibacter asiaticus' (CLas) is a non-culturable phloem-limited α-proteobacterium transmitted by Asian citrus psyllids (ACP, Diaphorina citri Kuwayama). A widely adopted method for HLB diagnosis is based on quantitative real-time polymerase chain reaction (qPCR). Although HLB diagnostic qPCR provides high sensitivity and good reproducibility, it is limited by time-consuming DNA preparation from plant tissue or ACP and the requirement of proper lab instruments including a thermal cycler to conduct qPCR. In an attempt to develop a quick assay that can be deployed in the field for CLas detection, we developed a real-time loop-mediated isothermal amplification (rt-LAMP) assay by targeting the CLas five copy nrdB gene. The rt-LAMP assay using various plant sample types and psyllids successfully detected the nrdB target as low as ~2.6 Log10 copies. Although the rt-LAMP assay was less sensitive than laboratory-based qPCR (detection limit ~10 copies), the data obtained with citrus leaf and bark and ACP showed that the rt-LAMP assay has >96% CLas detection rate, compared to that of laboratory-based qPCR. However, the CLas detection rate in fibrous roots was significantly decreased compared to qPCR due to low CLas titer in some root DNA sample. We also demonstrated that the rt-LAMP assay can be used with a crude leaf DNA extract which is fully deployable in the field for quick and reliable HLB screening.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.610-617
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• 2016

Current study was performed to investigate the effect of morphological properties of black ginseng such as size and shape on the quality of black ginseng. The raw ginsengs were separated based on size (medium, large, and extra-large) and shape (straight ginseng, fibrous root ginseng). Subsequently, the raw ginsengs were steamed at $95^{\circ}C$ for 3 h and dried in the presence of heated air at $50^{\circ}C$ for 30 h. This process was repeated nine times for black ginseng production. The physiochemical properties such as the content of acidic polysaccharides, ginsenosides, and antioxidative activity were evaluated. Although minor difference in physiochemical properties such as acidic polysaccharide content in raw ginseng was observed, no statistical difference in the content of acidic polysaccharides, total phenols, and ginsenosides was observed during final black ginseng production based on size classification. The minor ginsenosides in fibrous root black ginseng, such as Rk3, Rh4, Rg3, Rk1, and Rg5 were higher in content than straight black ginseng. However, no correlation between the shape of ginseng and total phenol content and antioxidative activity was observed. Therefore, present results demonstrate that the difference in ginseng size in same-age and -production area does not affect the quality of black ginseng. Furthermore, difference in ginseng shape does not influence the overall quality of black ginseng. It is hypothesized that this study would be considered as supportive data for the production of high-quality black ginseng.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.735-751
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• 1996

An ultimate goal of periodontal therapy is to stop the disease process and to regenerate a functionally-oriented periodontium destroyed as a result of periodontal disease. The purpose of this study was to observe the effect of grafting granulation tissue obtained from extraction socket on the regeneration of horizontal furcation defect. Six dogs were used in this study. All mandibular first and third premolars were extracted. At 2, 3, and 5 days after extraction, tissues were obtained from extraction socket of 1 mongrel dog and examined by light microscope. Granulation tissue obtained at 5 days after extraction was chosen as the graft material. Five days later, horizontal furcation defects were created surgically at mandibular second and fourth premolars in the right and left side of the 5 beagle dogs. The entrance area of the artificially prepared "key hole" defects were about $3\;4mm^2$. By random selections, 2 exposed furcation defects were grafted with granulation tissue obtained from extraction socket as experimental group and 1 furcation defect was as control. The flaps were replaced to their original position and sutured with 4-0 chromic cat-gut. Three dogs were sacrificed 4 weeks and two dogs 8 weeks after surgery, and the prepared specimens were examined by light microscope. At 4 weeks, furcations were filled with epithelial lining and fibrous connective tissue infiltrated with chronic inflammatory cells. New bone formation was observed in all groups. Only experimental group showed new cementum formation. At 8 weeks, new cementum, functional arrangement of new PDL fiber, root resorption, and some ankylotic union of newly formed alveolar bone and root surface were observed in all groups. Experimental group showed that epithelial downgrowth was inhibited and new bone formation was more active compared to control. The success rate of the furcation defect healing was higher in experimental group than control. These results suggested that grafting of granulation tissue obtained from extraction socket which combined with reconstructive periodontal flap surgery may promote periodontal regeneration of horizontal furcation defect.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.483-487
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• 2001

This study was carried out to investigate the role of attached leaflet on rooting and growth by one nodal cutting in tomato. As cutting sources 4 to 6 nodes could be obtained from one nursery seedling. Medium for cutting was a mixture with perlite plus peat moss (1 : 1, v/v), and each plug capacity was 30mL in the 72 cells-plug tray. Plant height and the number of leaves were significantly increased by attached leaflet cutting in 'Pepe' and 'Coco' cherry tomato. Dry weights of top and root were increased as much as 3 to 15 times in the cutting attached leaflet. Rooting percentage was 93.5% in one node cutting and 86% in the cutting with hypocotyl node part. At 20 to 24 days after nodal cutting, healthy nursery plant could be produced to transplant in field. The nursery plants by nodal cutting (NPNC) showed more fibrous roots and less tap roots than that of seedling. In terms of rooting pattern, NPNC rooted at the whole ground stem part, while rooting of seedling occurred at basal part of hypocotyl.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.1
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• pp.1-8
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• 2002

Chufa (Cyperus esculentus L.) belongs to one of the sedge family and pows well in summer. The aboveground part of chufa is mostly consisted of leaves and the underground part is mostly composed of a clump of fibrous root with tuber. At the seeding year, it does not reproductive development but produces a lot of tuber. It produced many tillers from the tuber and grows in clumps as a bunch type. The plant height of mature chufa was 73 to 75cm and it grown fully in the middle of July. The number of tillers were increased rapidly until the end of July and still increased slowly after August but it showed very poor growth. The final fresh weight and dry matter yield of aboveground part of chufa were 40.3 tou/ha and 12.1 tou/ha. respectively. The regrowth of aboveground part was vigorous in the early stage of growth after 1st cutting but it was decreased rapidly after the second cutting. In control plot, the number of tubers per a clump were 722 at final stage and their fresh and drymatter yields per m: were 4.2kg and 1.9kg, respectively. In experimental plots, the amount of tubers was decreased steadily according to delay of cutting date, but late cutting date was not affect the tuber formation severely because the tuber produced already early in August. The nutritive value of chufa in vegetative growth stage was good but it was decreased according to growing up. The contents of crude protein(CP), neutral detergent fiber(NDF), dry matter digestibility (DMD) and total digestible nutrients(TDN) of aboveground part of chufa harvested finally were 6.1%, 51.5%, 39.8%, 33.2% and 39.4％, respectively. The contents of crude protein(CP), neutral detergent fiber(NDF), dry matter digestibility(DMD) and total digestible nutrients(TDN) of tubers of chufa were 6.1%, 81.5%, 39.8%, 33.2% and 39.4%, respectively and the content of oil was as high as 16.2%, especially.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.161-168
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• 2017

BACKGROUND: Rabbiteye blueberry(Vaccinium ashei Reade) has low nutrient uptake efficiency due to its shallow and fibrous root system without root hairs. This study was carried out to establish an efficient nutrient application standard by investigating the effect of nitrogen fertigation on the growth and fruit characteristics of rabbiteye blueberry. METHODS AND RESULTS: 'Brightwell' rabbiteye blueberry was treated with 0, 50, 100 and 200% nitrogen fertigation of recommended fertilizer application (6, 9 and 14 g/bush in the first, second and third years, respectively). The results showed that leaf nitrogen content significantly correlated with the fruit weight and fruit yield. However, canopy area, dry weight, sugar and anthocyanin contents did not correlate significantly with the leaf nitrogen content. The leaf and stem dry weights of 'Brightwell' rabbiteye blueberry during the third year of planting were the highest with 50% nitrogen fertigation (leaf dry weight=723.7 g/bush; stem dry weight=890.7 g/bush). Maximum fruit yield of 'Brightwell' rabbiteye blueberry (12.9 kg/bush) was observed during the third year of planting with 50% nitrogen fertigation and this was about 70% greater than the treatment that received no nitrogen fertigation. The fruit yields of 'Brightwell' rabbiteye blueberry during the third year of planting treated with 100 and 200% nitrogen fertigation were 11.0 and 11.5 kg/bush, and these were 17 and 12%lower than the 50% nitrogen fertigation treatment, respectively. Further, the efficiency of nitrogen utilization was the highest (90%) with 50% nitrogen fertigation and lowest (18%) with 200% nitrogen fertigation. CONCLUSION: The results of this study suggests that fertigation with 50% of the recommended fertilizer could be most effective for enhancing the growth and nitrogen use efficiency of rabbiteye blueberry.

• 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.

• Korean Journal of Environmental Biology
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• v.29 no.2
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• pp.92-97
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• 2011

Morphological and physiological differences of $Colocasia$ $esculenta$ were investigated in the cultivation of hydorphonic and soil culture. $C.$ $esculenta$ grown in Hoa.+IAA (indole-acetic acid) showed higher growth activity representing 9%, 32%, 38% and 60% than those of the cultivation of vermiculate, Hoagland solution, soil and water, respectively. In case of $F_v/F_m$ ratio experiments, the value $F_v/F_m$ of $C.$ $esculenta$ cultivated in the water showed 0.55 after 6 weeks. $F_v/F_m$ values of $C.$ $esculenta$ cultivated in Hoagland+IAA, vermiculate and soil were between 0.84 and 0.80 indicating $F_v/F_m$ values were about 45% higher than that of $C.$ $esculenta$ cultivated in the water. Diffusion resistance was 45~35% lower in $C.$ $esculenta$ grown in Hoa.+IAA solution than that of $C.$ $esculenta$ grown in water only after 5 and 6 weeks. Therefore, the high standing levels of the growth rate, fluorescence activity and transpiration rate were Hoa.+IAA, vermiculate, Hoagland, soil and water. The distinct morphological differences of $C.$ $esculenta$ cultivated in hydorphonic and soil culture were the appearance of the seed corm and root hair. The development of seed corm was well established in soil culture but the corm in hydorphonic was slowly hydrolyzed and then disappeared. The fibrous root systems of hydorphonic were very well distinguishable compared with that in soil culture. Outstanding results of this experiment were appeared in $C.$ $esculenta$ which was cultivated in the field provided with enough mineral nutrition, organic fertilizers and compound fertilizers. The most height taros were almost 2m and the numbers of seed corm were 30~40 after 7 months.