• Animal cells and systems
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• v.12 no.4
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• pp.287-295
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• 2008

Variations of larval abundance and hatch timing of Dungeness crabs, Cancer magister Dana 1852, were investigated. Dungeness crab larvae were monthly collected at 16 stations arrayed in four transects, Upper Chatham, Icy Strait, Cross Sound, and Icy Point, in southeastern Alaska from May to September 1997-2004. Larval abundance at all transects was the highest in June except in the Icy Point transect. Larval abundance was the highest in the Icy Strait transect, moderate in the Upper Chatham and Cross Sound transects, and the lowest in the Icy Point transect. Zoeae I(ZI) was predominated in May; thereafter ZI decreased and late zoeal stages occurred. In May and June, small numbers of late stage larvae unusually co-occurred with ZI in three transects. These late stage larvae may have been transported from where hatching occurs earlier. The timing of ZI occurrence varied interannually and was related to degreedays during the egg incubation period of Dungeness crabs: later larval hatching in 1997 and 2002 when temperatures were colder, while earlier larval hatching in 1998 when temperatures were warmer. The distribution patterns of Dungeness crab larvae in southeastern Alaska were markedly different from those reported from other areas of the species distribution ranges: larvae occurring much later in the year, and late stage larvae occurring in inland waters.

• Animal cells and systems
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• v.12 no.4
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• pp.203-209
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• 2008

Berberine, an isoquinoline alkaloid found in Coptidis Rhizoma(goldenthread) extract, has multiple pharmacological effects such as anti-inflammatory, antimicrobial and anti-ischemic effects. In the present study, we examined the effects of berberine on neuronal survival and differentiation in a hippocampal precursor cell line and in the memory deficient rat model. Berberine increased in a dose dependent manner the survival of hippocampal precursor cells as well as differentiated cells. In addition, berberine promoted neuronal differentiation of hippocampal precursor cells. In the memory deficient rat model induced by stereotaxic injection of ibotenic acid into entorhinal cortex(Ibo model), hippocampal cells were increased about 2.7 fold in the pyramidal layer of CA1 region and about 2 fold in the dentate gyrus by administration of berberine after 2 weeks of ibotenic acid injection. Furthermore, neuronal cells immunoreactive to calbindin were increased in the hippocampus and entorhinal cortex area by administration of berberine. Taken together, these results suggest that berberine has neuroprotective effect in the Ibo model rat brain by promoting the neuronal survival and differentiation.

• Journal of Applied Biological Chemistry
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• v.42 no.3
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• pp.146-150
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• 1999

As a part of the integrated disease system in greenhouse, an antifungal fungus(AF1) was isolated from greenhouse soil. It exhibited strong inhibitory activites against Pythium ultimum, Phytophtora capsici, Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum based on dual culture on 1/5 strength of potato dextrose agar between antagonistic fungus and several plant pathogens. The antagonistic fungus was identified as Chaetomium cochliodes, based on morphological characteristics; the body of the perithecium bears straight or slightly wavy, unbranched hairs, whilst the apex bears a group of spirally coiled hairs. To investigate antagonistic principles, antifungal compound was extracted and fractionated by different solvent systems. An antifungal compound was isolated as pure crystal from is culture filtrate using organic solvent extraction and column chromatography, followed by preparative thin layer chromatography. The chemical structure of the purified antifungal compound was identified as chaetoglobosin A based on the data obtained form $^1H-NMR$, $^{13}C-NMR$, DEPT 90, 135, $^1H-^1H$ COSY, $^1H-^{13}C$ COSY and EI/MS. $ED_{50}$ values of the chaetoglobosin A against P. ultimum, P. capsici, R. solani, B. cinerea and F. oxysporum were 1.98, 4.01, 4.16, 2.67 and 35.14 ppm, respectively.

• Korean Journal of Plant Tissue Culture
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• v.26 no.2
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• pp.99-102
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• 1999

Glucose - induced arginine transport system was induced by a exogenous application of NH$_4$^+ ion. The uptake rate of arginine (Arg) depended on the external NH$_4$^+ ion concentration. The uptake rate was inhibited by the presence of NH$_4$^+ ion within 1 min, whereas it increased maximally after 30 min. Glucose and NH$_4$^+ ion induced the same arginine transport system. Km value of Arg transport systems was 2 $\mu$M, and V_(max) was 60 $\mu$mol^(-1) . h . g fresh weight^(-1) for NH$_4$^+ ion and 174 $\mu$mol^(-1) . h . g fresh weight^(-1) for glucose induced transport system. But, the transport system of Glu for glucose and NH$_4$^(-1) ion induced had different Km values. Km value of Glu was 285 $\mu$M for glucose - and 58 $\mu$M for NH$_4$^+ ion induced transport system. Thus, NH$_4$^+ ions play a important role as inducer for the glutamine transport system. NH$_4$^+ ion induced glutamine system was inhibited over 90% by cycloheximide. We concluded that a new carrier protein for glutamine was induced by NH$_4$^+ ion.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.513-523
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• 2009

Many species, cultivars, and hybrids in Populus have been introduced and developed by the scientists of Department of Forest Genetic Resources, Korea Forest Research Institute in Korea. P. alba ${\times}$ glandulosa, P. euramericana, P. nigra ${\times}$ maximowiczii, P. koreana ${\times}$ P. nigra var. italica, and P. davidiana have been studied from many aspects, i.e., genetics, breeding, physiology, propagation, silviculture, biomass production, biotechnology and phytoremediation. These precedent results will provide a sound basis for a newly-arising research on short-rotation coppice as one of renewable resources and phytoremediation plants. It was found that there were many promising varieties and clones for these purposes. However, minute analysis on specific gravity and caloric values for those plants should be followed under several silvicultural and rotational systems.

• KSBB Journal
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• v.9 no.3
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• pp.294-298
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• 1994

The medium additives such as CaCl2, glucose, fructose, glutamine, glutamate and lipids were examined to enhance recombinant ${\beta}$-galactosldase(${\beta}$-gal) production in batch and continuous two-stage bioreactor systems. The presence of each medium additive such as CaCl2, fructose, glutamate, cholesterol and tocopherol at AcNPV infection of Sf 21 cells had an effect on improved ${\beta}$-gal production. The recombinant ${\beta}$-gal production using the infection media supplemented with a mixture of 30mM $CaCl_2$, 2.2mM fructose, 4.1mM glutamate and 0.34mM cholesterol was increased by about 40%.

• KSBB Journal
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• v.5 no.2
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• pp.119-124
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• 1990

Phospholipase D catalyzes the phosphatidohydrolysis and transphosphatidylation of phospholipid in the biological systems. In this study we were partially purified phospholipase D from Chinese cabbage and the characterization of the enzyme was carried out in a multistirring batch system bioreactor. The enzyme showed optimum activity at pH ,5.6, highest activity at 37$^{\circ}C$ and Ca2+ is important for the enzyme activity. Optimum concentrations of Ca2+ for phosphatidohydrolysis was 20 mM and for transphosphatidylation was 40 mM, respectively. Some organic solvents such as diethylether, isopropylether and butylacetate were activated the enzyme activity. On the other hand, EDTA, Ba2+, Mn2+ and Zn2+ showed inhibitory effect on the enzyme activity. The base acceptors in transphosphatidylation by the Chinese cabbage phospholipase D were tested. Various poly-and monohydroxy alcohols were found to be active.

• KSBB Journal
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• v.28 no.1
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• pp.24-30
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• 2013

Dissolved oxygen, pH and cell concentration have been online monitored in cultivation processes with Escherichia coli by using a $MABOOMS^{TM}$ (microplate-based bioreactor with optical online monitoring systems). Fluorescent sensing membranes containing Ru ${(dpp)_3}^{2+}$ or HPTS were prepared with GA sol-gel matrix and coated into a well of a 24-well microplate. Fluorescence intensity was measured and correlated to the dissolved oxygen or pH. Cell concentrations were also online monitored by measuring optical reflectance at 650 nm. A well of a 24-well microplate could also be divided into 4 parts, each of which was coated with fluorescent sensing membranes for the detection of dissolved oxygen or pH. The 24-well microplate coated with fluorescent sensing membranes or a 4-divided sensing membrane. was used to online monitor the dissolved oxygen, pH and cell concentration during E. coli cultivations. The online monitoring results showed the characteristics of cell growth in cultivation processes very well.

• BMB Reports
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• v.41 no.8
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• pp.575-580
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• 2008

Thymocyte-specific transcriptional regulatory systems can be used to better understand the relationship between transcription and V(D)J recombination during early T cell development. In this study, we generated transgenic mice expressing the transactivator Gal4-VP16 or the Gal4 DNA binding domain (Gal4-DBD) under the control of the lck proximal promoter, which is only active in immature thymocytes. From these studies Gal4-VP16 and Gal4-DBD expression was shown to significantly alter thymic cellularity and differentiation without significantly changing the $CD3^+$ thymocyte distribution. Furthermore, the presence of Gal4-VP16 or Gal4-DBD in the transgenic thymocytes retarded the mobility of the Gal4 DNA binding motif as determined by a gel mobility shift assay, suggesting that the developmental alteration did not affect the functional property of the transgenic proteins. These results indicated that lck promoter-driven Gal4-VP16 or Gal4-DBD expression did not affect $CD3^+$ mature thymocytes, thus this system can be applied to study transcriptional regulation of transresponder genes in bigenic mouse model thymocytes.

• Animal cells and systems
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• v.14 no.4
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• pp.343-349
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• 2010

Ultrastructural studies of vitellogenesis in oocytes and follicle cells during oogenesis in female Protothaca (Notochione) jedoensis were investigated by histological and transmission electron microscope observations. In early vitellogenic oocytes, combined activities of the Golgi complex, mitochondria and rough endoplasmic reticulum in the cytoplasm are associated with autosynthetic vitellogenesis. Furthermore, at this time, many coated vesicles at the basal region of the oolemma of the oocyte lead to the formation of vesicles through endocytosis in the cytoplasm. Through the formation of the coated pits on oolemma during vitellogenesis, the uptake of extrafollicular precursors (nutritive materials) occurs in coated vesicles by endocytosis. Therefore, it is assumed that these exogenous materials are involved in heterosynthetic vitellogenesis. During late oogenesis, exogenous yolk precursors (yolk granules), lipid droplets and proteinaceous yolk granules are present in the cytoplasm of late vitellogenic oocytes. In mature oocytes, small yolk granules appear intermingled and form large mature yolk granules. Thus, two processes of vitellogenesis occur in oocytes by way of endogenous autosynthesis and exogenous heterosynthesis. The follicle cells attached to the oocytes appear to play an integral role in vitellogenesis in this study.