• Korean Journal of Medicinal Crop Science
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• v.2 no.2
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• pp.154-161
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• 1994

This experiment was carried out to establish micropropagation system in Fritillaria thunbergii Miq. Through the culture of bulblet scales, stems, node-buds and shoot tips with special reference to the effect of physiological age of explant and plant growth regulators on bulblet formation. Number of formed bulblets was significantly increased in node-bud or stem tissue compared to scals segments and on the medium supplemented with kinetin than BA containing medium. Optimum levels of kinetin for bulblet formation from node-bud taken from above 3 cm shoot length and stem segments excised from below 3 cm shoot length were 5.0 mg /L and $1.0{\sim}3.0\;mg$ /L kinetin, respectively. Interesting phenomenon was observed, the direct formation of bulblets from the axilliary bud of cultured explants. Bulblet forming capacity in stem tissue was depended on stem age, young stem had high regeneration ability compared to old stem taken from above 10 cm shoot length. 1.0 mg /L kinetin was optimum concentration for the formation of bulblets from old stem segments. Stem tissue taken from underground growing plant was promoted coampare to shoot tips or bulb scale segments. Optimum concentration of sucrose was $5{\sim}7%$. Summariged above results revealed that effective explant for micropropagation was stem and /or node-bud tissue excised from less than 3 cm plant height compared to those of bulb scale segments which showed high contamination after culture. Maximum multiplication rate of young stem and /or node-bud segment was about 20 times. Kinetin requirement for stimulation of bulblet formation from cultured explant depended on source of explants but favorable levels of kinetin for organogenesis ranged from 1.0 mg /L to 5.0 mg /L.

• BMB Reports
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• v.45 no.12
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• pp.742-747
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• 2012

Granulocyte colony-stimulating factor (G-CSF) is used for heart failure therapy and promotes myocardial regeneration by inducing mobilization of bone marrow stem cells to the injured heart after myocardial infarction; however, this treatment has one weakness in that its biological effect is transient. In our previous report, we generated 5 mutants harboring N-linked glycosylation to improve its antiapoptotic activities. Among them, one mutant (Phe140Asn) had higher cell viability than wild-type hG-CSF in rat cardiomyocytes, even after treatment with an apoptotic agent ($H_2O_2$). Cells treated with this mutant significantly upregulated the antiapoptotic proteins, and experienced reductions in caspase 3 activity and PARP cleavage. Moreover, the total number of apoptotic cells was dramatically lower in cultures treated with mutant hG-CSF. Taken together, these results suggest that the addition of an N-linked glycosylation was successful in improving the antiapoptotic activity of hG-CSF, and that this mutated product will be a feasible therapy for patients who have experienced heart failure.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.259-266
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• 1998

A study on the biological and chemical characteristics in the middle last Sea of Korea was carried out at 31 stations in October $11\~18$, 1995 on board the R/V Tam-Yang. The chlorophyll a concentration, new and regenerated production, and the vertical diffusion of nitrate from the thermocline structure were investigated. From the vertical distribution of chlorophyll a, subsurface maxima were observed near the thermorline at most stations including the frontal zone, except at the southern stations where the maximum chloropyll a concentration occurred at the surface, The nanophytoplankton was the most dominant fraction comprising $83.5\%$ of total phytoplankton cell numbers, but netphytoplankton were common at the southern stations where the dominant species were Rhizosolenia sp. Nitrogenous new production and regenerated productions were measured using the stable isotope $^{15}N$ nitrate and ammonia uptake method. The vertically integrated nitrogen production varied between 8.470 and $72.945\;mg\;N\;m^{-2}\;d^{-1}$. The f-ratio, which is the traction of new production from primary production, waried between 0.03 and 0.72, indicating that $3\%$ to $72\%$ of primary production was supported by the input of nutrients from below the euphotic zone and the rest are supported by ammonia recycled within the euphotic layer. This range of f-ratio encompasses from extremely oligotrophic to eutrophic area characteristics. The differences in productivity and f-ratio among stations were related to frontal structure and the bottom topography. The values were high near the frontal zone and low outside of it, and the station near Ulleng Island showed the highest f-ratio. Vertical diffusion coefficients were calculated from both the water column stability (Kz-1) of King and Devol's equation (1979) and new nitrogen requirement (Kz-2). The values of Kz-2 ($0.11\~0.55\;cm^2/s$) were relatively low compared to the values reported previously.

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.393-407
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• 1991

The vegetation structure within Chamaecyparis obtusa plantation was analyzed for the purpose of applying the effective forestation method for Chmaecyparis obtusa plantation, tending and regeneration in the southern districts of korea. The results were as follows ; 1. The importance percentage was high in the order of Eurya japonica, Rhus verniciflua, Chamaecyparis obtusa, Lindera erythrocarpa, Carpinus laxiflora, Styrax japonica, Viburnum dilatatum, Zanthoxylum piperitum and Smilax china among the vegetation of Chamaecyparis obtusa. Importance percentage of natural seedling of Chamaecyparis obtusa was high in lower story but gradually decreased in middle story. 2. The basal area of upper trees had a negative correlation with the density of natural seedlings in the middle and lower story, and it represents that the basal area of upper trees had some effect on the density of natural seedlings within understories. 3. The rate of the A and B class by Raunkiaer's frequency was higher in the vegetation of middle story than that of lower story. 4. By Morisita's index, the species of Chamaecyparis obtusa, Rhus verniciflua, Lindera erythrocarpa, Smilax china. Callicarpa japonica and Lindera obtusiloba were randomly distributed at lower story, but they were aggregatively distributed at middle story. At all of middle and lower story, Eurya japonica and Viburum dilatatum were randomly distributed, and Carpinus laxiflora, Zanthoxylum piperitum and Picrasma quassioides were aggregatively distributed. 5. The number of appearance species and the value of species diversity in western survey area were more than that of eastern survey area. 6. The value of species diversity at lower story was higher than that of middle story, and it represents that the number of individuals of appearance species was composed more even at lover story than middle story. 7. According to cluster analysis by similarity index, the survey areas were separated from inland and seacoast districts. 8. Judging from each stories ordination analysis by dissimilarity index, the vegetation was separated from lower and middle story, and the vegetation of lower story was more progressed succession stage than that of middle story. 9. In Chamaecyparis obtusa stands, Eurya japonica had a positive correlation with Sorbus alnifolia, Hex macropoda. Ficus erecta and Trachelospermum asiaticum, but it had a negative correlation with Zanthoxylum piperitum, Carpinus laxiflora and Parthenocissus tricuspidata. 10. In estimation of the productivity of Chamaecyparis obtusa stands, the value of SC (Conic surface) and VP (Parabolic volume) for upper trees was 94.5% and 99.63%, respectively and SC and VP of middle story was 5.49% and 0.37%, respectively. In the species of middle story, material productivity was high in order of Eurya japonica. Lindera eryhrocarpa, Rhus verniciflua. Carpinus laxiflora and Styrax japonica.