• Korean Journal of Plant Tissue Culture
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• v.25 no.4
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• pp.219-223
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• 1998

Anthers contanining uninucleate microspores of eight cultivars of pepper were cultured on MS medium supplemented with 0.004mg/L 2,4-D and 0.1mg/L kinetin, 3% sucrose and 0.2% Gelrite, kept at $35^{\circ}C$ for 24 h, and then cultured at $25^{\circ}C$ with a photoperiod of 16 h daylight for 40 days. Frequency of embryoid and callus formation was varied with cultivars. Embryoid formation was found in Cheongyang and Fushimi Amanaga, while callus formation was in California Wonder, Fushimi Amanaga and Geoseong. In anther culture medium supplemented with 1% activated charcoal, embryoid formation was found with 0.5% of frequency only in Cheongyang, while no callus formation was found. In 1/2MS medium, frequency of embryoid formation in Shishitou, Yatsufusa and Taka no Tsume was 1.2%, 0.4% and 0.4%, respectively. On the other hand, in 1/2 B5 medium, frequency of callus formation in Yatsufusa and Taka no Tsume was 2.8% and 2.7%, respectively. Embryoids transferred to hormone-free MS medium were developed to plantlets and acclimatized. The number of chromosomes in the root tip cells of the haploid plant was 2n=$\times$=12 in cv. Cheongyang.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.207-217
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• 1998

Total of 78 strains were characterized based on the morphological characteristics of colonies isolated on Schroth, and New & Kerr's media for selection of hypervirulent wild-type Agrobacterium spp from galls, hairy root-like process and soil of Populus, Malus, Salix and Diopyros in Korea. Among them, 48 strains were able to induce tumors in carrot disc. Hypervirulent A. tumefaciens SP101 and SM042 were identified as biotype 1 and biotype 2, respectively, These strains formed fast growing, larger tumors as compared to those induced by other strains. The binary vector pGA643 with kanamycin resistant gene was mobilized from E. coli MC100 into A. tumefaciens strain SM042 isolated from soil, and/or disarmed vector PC2760 using a triparental mating method with E. coli HB101/pRK2013, and transconjugants, A. tumefaciens SM643 and PC643 were obtained in minimal media containing kanamycin and tetracycline. Tobacco tissues were cocultivated with conjugant Agrobacterium and then transferred to selective medium with 2,4-D and kanamycin to induce the transformants. Calli were formed more efficiently in cocultivation with A. tumefaciens SM643 than that with A. tumefaciens PC643. Most of calli transformed with A. tumefaciens PC643 were friable and regenerated into normal plantlets, while the calli transformed with A. tumefaciens SM643 were compact, hard, and mixed with friable calli. The friable calli formed normal shoots, while compact calli did not form shoots but only grew to typical compact tumor calli. When the shoots formed directly from tobacco stems without callus induction after transformation by A. tumefaciens SM643 with wild-type Ti-plasmid, normal transformed plants can be induced without using disarmed Ti-plasmid.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.103-108
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• 2001

The in vitro plantlets of cassava (Manihot esculenta Crantz cv. MColl 22) could be regenerated from nodal explant cultures in a liquid MS basal medium containing 0.01 mg/L zeatin for 2 weeks. The plantlets of 1.5∼2.5 cm in shoot length were transplanted to a glass bottle containing fine sand and acclimated under non-sterile conditions after excising their intact roots by: 1) prune leaving roots base of 1∼1.5 cm; 2) complete removal of roots; and 3) cutting off the rooting zone. The majority of in vitro-formed intact roots continued growth after transferred to soil, and all of the damaged roots stopped further growth. The plantlets with excised roots began to develop new roots within 7∼10 days after being transferred to a glass bottle, and a few of the pruned roots developed lateral roots from the remaining portion. Pruning and removal of in vitro roots resulted in a high survival rate (>87%), and did not significantly affect ex vitro root regeneration and acclimation, but the plantlets in which the rooting zone had been cut-off showed 73% survival rate. Pruning or removal of in vitro roots before transfer of plantlets is recommended for useful method of commercial micropropagation because of easier handling and high survival rate of plantlets.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.185-189
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• 2000

For the micropropagation, node explants of cassava were cultured in liquid MS medium with various concentrations of cytokinins on a rotary shaker (100 rpm) for 2 weeks. The adventitious roots and shoots from the explants were differentiated more efficiently in liquid medium than in solid. But root formation was not inhibited in medium with BAP and kinetin at low concentration (＞0.05 mg 1/sup -1/), while in medium added with BAP and zeatin at high level (＜0.25 mg 1/sup -1/), it was inhibited by callus forming on cut end of the cuttings. However, all of plantlets grown in liquid medium for more than 2 weeks showed symptoms of hyperhydricity. The plantlets grown in liquid medium were transferred into culture bottles filled with fine sand or artificial soil (pitmoss：perlite：vermiculite, 1：1：1 v/v) wetted with half strength of Knop's solution. After transplanted to culture bottles, some of vitriscent leaves were defoliated and new leaves were normally formed from shoot apex. Most of plantlets (＞95%) were hardened-off successfully only in culture bottles with fine sand, and grew into 3-5 cm seedlings possessing 4-6 nodes after 4 weeks. Thus, the mass propagation of cassava on medium containing cytokinin could be established based on the suspension culture using node explants.

• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.50-56
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• 2010

This experiment was carried out to examine the effect of a silicate fertilizer on the growth and development of potted plants. Cutting of Kalanchoe blossfeldiana 'Kaluna' and 'Taos', and Dianthus caryophyllus L. 'Kazan' and 'Tula' were grown in 50 and 128-cell plug trays, respectively. Rooted cuttings transplanted to the mixture of a commercial medium and perlite (5:1, v/v) supplemented with a silicate fertilizer at 0, 40, 80, 120 or $160g{\cdot}L^{-1}$ medium was evaluated. A silicate fertilizer supplementation at $40g{\cdot}L^{-1}$ medium resulted in the greatest plant height, leaf thickness, and root fresh and dry weights in both kalanchoe and carnation. However, plant height was suppressed in the treatment of a silicate fertilizer supplementation at higher concentrations in both kalanchoe and carnation. According to the scanning electron microscope images of transversal sections of tissues of roots and leaves in kalanchoe and carnation, the treatment of a silicate fertilizer supplementation at $40g{\cdot}L^{-1}$ medium resulted in plants with more compact tissue than the control.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.397-403
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• 2015

Heavy metals reduce the photosynthetic efficiency and disrupt metabolic reactions in a concentration-dependent manner. Moreover, by replacing the metal ions in metalloproteins that use essential metal ions, such as Cu, Zn, Mn, and Fe, as co-factors, heavy metals ultimately lead to the formation of reactive oxygen species (ROS). These, in turn, cause destruction of the cell membrane through lipid peroxidation, and eventually cause the plant to necrosis. Given the aforementioned factors, this study was aimed to understand the physiological responses of rice to cadmium (Cd) and arsenic (As) toxicity and the effect of essential metal ions on homeostasis. In order to confirm the level of physiological inhibition caused by heavy metal toxicity, hydroponically grown rice (Oryza sativa L. cv. Dongjin) plants were exposed with $0-50{\mu}M$ cadmium (Cd, $CdCl_2$) and arsenic (As, $NaAsO_2$) at 3-leaf stage, and then investigated malondialdehyde (MDA) contents after 7 days of the treatment. With increasing concentrations of Cd and As, the MDA content in leaf blade and root increased with a consistent trend. At 14 days after treatment with $30{\mu}M$ Cd and As, plant height showed no significant difference between Cd and As, with an identical reduction. However, As caused a greater decline than Cd for shoot fresh weight, dry weight, and water content. The largest amounts of Cd and As were found in the roots and also observed a large amount of transport to the leaf sheath. Interestingly, in terms of Cd transfer to the shoot parts of the plant, it was only transported to upper leaf blades, and we did not detect any Cd in lower leaf blades. However, As was transferred to a greater level in lower leaf blades than in upper leaf blades. In the roots, Cd inhibited Zn absorption, while As inhibited Cu uptake. Furthermore, in the leaf sheath, while Cd and As treatments caused no change in Cu homeostasis, they had an antagonist effect on the absorption of Zn. Finally, in both upper and lower leaf blades, Cd and As toxicity was found to inhibit absorption of both Cu and Zn. Based on these results, it would be considered that heavy metal toxicity causes an increase in lipid peroxidation. This, in turn, leads to damage to the conductive tissue connecting the roots, leaf sheath, and leaf blades, which results in a reduction in water content and causes several physiological alterations. Furthermore, by disrupting homeostasis of the essential metal ions, Cu and Zn, this causes complete heavy metal toxicity.

• Korean Journal of Heritage: History & Science
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• v.36
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• pp.267-297
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• 2003

The plain coarse pottery from the Unjeonri Bronze Age relic sites in the Cheonan, Korea were studied on the basis of clay mineralogy, geochemistry and archaegeological interpretations. For the research, the potteries are utilized at the analysis for 6 pieces of plain coarse potteries. Color of the these potteries are mainly light brown, partly shows the yellowish brown to reddish brown. The interior, surface and inside of the pottery appear as different colors in any cases. Original source materials making the Unjeonri potteries are used of mainly sandy clay soil with extreme coarse grained irregularly quartz and feldspar. The magnetic susceptibility of the Unjeonri pottery range from 0.20 to 1.20. And the Unjeonri soil's magnetic susceptibility agree almost with 0.20 to 1.30. In the same magnetization of soil and pottery, the results revealed that the Unjeonri soil and low material of pottery are same produced by identical source materials. The Unjeonri potteries and soil are very similar patterns with all characteristics of soil mineralogy, geochemical evolution trend. The result seems to be same relationships between the behavior and enrichment patterns on the basis of a compatible and a incompatible elements. Consequently, the Unjeonri potteries suggest that made the soil to be distributed in the circumstance of the relic sites as the raw material are high in a greater part. In the Unjeonri soil, the kaolinite is common occurred minerals. However, in the Unjeonri pottery, the kaolinite was not detected in all broken pieces. The kaolinite was presumed to destroy crystal structure during the firing processes of over $550^{\circ}C$. The quartz is phase transition from ${\alpha}$-quartz to ${\beta}$-quartz at $573^{\circ}C$, but the Unjeonri pottery did not investigated any phase transition evidences of quartz. The chorite was detected within the mostly potteries and soils. As the results, the Unjeonri potteries can be interpreted by not experiencing a firing temperature over $800^{\circ}C$. The colloidal and cementing materials between the quartz and low materials during the heating did not exist in the internal part of the potteries. An any secondary compounds by heating does not appear within the crack to happen during the dry of the pottery. The hyphae group are kept as it is with the root tissue of an organic matters to live in the swampy land. In the syntheses of all results, the general firing condition to bake and make the Unjeonri pottery is presumed from $550^{\circ}C$ to $800^{\circ}C$. However, the firing condition making the Unjeonri pottery can be different firing temperature partially in one pottery. Even, the some part of the pottery does not take a direct influence on the fire.

• Research in Plant Disease
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• v.26 no.4
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• pp.256-263
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• 2020

Incidence of Fusarium wilt was surveyed in fields of summer radish in Gangwon province in Korea in 2018 and 2019. The disease started in early July and spread rapidly in hot summer of late July and August and in severe case, reached up to 80% in a field in Gangneung area. Symptoms in the seedling stage include poor growth and browning of internal tissue of root. During mid-growth, the leaves of diseased plant turned yellow over time, the surface of the roots changed from white to blackish, and the vascular tissues turned brown. A total of 23 isolates was obtained from the diseased plants and identified as Fusarium oxysporum f. sp. raphani by elongation factor-1α and intergenic spacer sequence analysis. Pathogenicity of the isolates was tested by artificial inoculation to the radish and other plants. All the isolates tested were pathogenic to radish plant, although there were differences in virulence on radish 11 cultivars. However, the isolates were not virulent to other plants except some cruciferous vegetables including Brussels sprouts, rocket, stock, and turnip. The results of pathogenicity test showed that it is necessary to rotate with crops other than cruciferous vegetables in order to prevent Fusarium wilt from radish fields.

• Journal of Periodontal and Implant Science
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• v.52 no.4
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• pp.338-350
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• 2022

Purpose: Various studies have investigated 3-dimensional (3D)-printed implants using Ti6Al-4V powder; however, multi-root 3D-printed implants have not been fully investigated. The purpose of this study was to explore the stability of multirooted 3D-printed implants with lattice and solid structures. The secondary outcomes were comparisons between the 2 types of 3D-printed implants in micro-computed tomographic and histological analyses. Methods: Lattice- and solid-type 3D-printed implants for the left and right mandibular third premolars in beagle dogs were fabricated. Four implants in each group were placed immediately following tooth extraction. Implant stability measurement and periapical X-rays were performed every 2 weeks for 12 weeks. Peri-implant bone volume/tissue volume (BV/TV) and bone mineral density (BMD) were measured by micro-computed tomography. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were measured in histomorphometric analyses. Results: All 4 lattice-type 3D-printed implants survived. Three solid-type 3D-printed implants were removed before the planned sacrifice date due to implant mobility. A slight, gradual increase in implant stability values from implant surgery to 4 weeks after surgery was observed in the lattice-type 3D-printed implants. The marginal bone change of the surviving solid-type 3D-printed implant was approximately 5 mm, whereas the value was approximately 2 mm in the lattice-type 3D-printed implants. BV/TV and BMD in the lattice type 3D-printed implants were similar to those in the surviving solid-type implant. However, BIC and BAFO were lower in the surviving solid-type 3D-printed implant than in the lattice-type 3D-printed implants. Conclusions: Within the limits of this preclinical study, 3D-printed implants of double-rooted teeth showed high primary stability. However, 3D-printed implants with interlocking structures such as lattices might provide high secondary stability and successful osseointegration.

• Journal of Nutrition and Health
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• v.55 no.6
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• pp.617-629
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• 2022

Purpose: Osteoporosis is characterized by structural deterioration of the bone tissue because of the loss of osteoblastic activity or the increase in osteoclastic activity, resulting in bone fragility and an increased risk of fractures. Hederagenin (Hed) is a pentacyclic triterpenoid saponin isolated from Dipsaci Radix, the dried root of Dipsacus asper Wall. Dipsaci Radix has been used in Korean herbal medicine to treat bone fractures. In this study, we attempted to demonstrate the potential anti-osteoporotic effect of Hed by examining its effect on osteoblast differentiation in MC3T3-E1 cells. Methods: Osteoblastic MC3T3-E1 cells were cultured in 0, 1, and 10 ㎍/mL Hed for 3 and 7 days. The activity of alkaline phosphatase (ALP), bone nodule formation and level of expression of bone-related genes and proteins were measured in MC3T3-E1 cells exposed to Hed. The western blot test was used to detect the activation of the bone morphogenetic protein-2 (BMP2)/ Suppressor of Mothers against Decapentaplegic (SMAD)1 pathway. Results: Hed significantly increased the proliferation of MC3T3-E1 cells. Intracellular ALP activity was significantly increased in the 1 ㎍/mL Hed-treated group. Hed significantly increased the concentration of calcified nodules. Furthermore, Hed significantly upregulated the expression of genes and proteins associated with osteoblast proliferation and differentiation, such as Runt-related transcription factor 2 (Runx2), ALP, osteopontin (OPN), and type I procollagen (ProCOL1). Induction of osteoblast differentiation by Hed was associated with increased BMP2. In addition, Hed induced osteoblast differentiation by increasing the activity of SMAD1/5/8. These results suggest that Hed has the potential to prevent osteoporosis by promoting osteoblastogenesis in osteoblastic MC3T3-E1 cells via the modulation of the BMP2/SMAD1 pathway. Conclusion: The results presented in this study indicate that Hed isolated from Dipsaci Radix has the potential to be developed as a healthcare food and functional material possessing anti-osteoporosis effects.