Publications by authors named "Do Hyun Jo"

Herpes disease caused by herpes simplex virus type 1 (HSV-1) is an intractable condition. It is a major concern in public health. Our purpose of this study was to verify the function of chitosan as an adjuvant for immune regulation specifically under herpes simplex virus type 1 (HSV-1) infection.

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We report the tissue-specific distribution of chitinolytic activity in Korean ginseng root and characterize two 31-kDa chitinolytic enzymes. These two enzymes (SBF1 and SBF2) were purified 70- and 81-fold with yields of 0.75 and 1.

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A novel oligomeric decaprenyl pyrophosphate synthase was identified. Circular dichroism measurements indicated that it is alpha-helical, and stable against pH changes and denaturants. Three peptides corresponding to the conserved regions were synthesized and metal affinities were investigated.

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The slow process required for alpha-synuclein to form amyloid fibrils is a major obstacle in the development of therapeutic compounds for alpha-synuclein-related neurodegenerative diseases such as Parkinson's disease (PD). Here we have developed an efficient method by which amyloid fibrils can be formed from alpha-synuclein using ionic liquids (ILs). This report indicates that ILs could potentially be used as a stimulator for the amyloid formation of alpha-synuclein.

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The domestic chicken (Gallus gallus) is an important model for research in developmental biology because its embryonic development occurs in ovo. To examine the mechanism of embryonic germ cell development, we constructed proteome map of gonadal primordial germ cells (gPGCs) from chicken embryonic gonads. Embryonic gonads were collected from 500 embryos at 6 days of incubation, and the gPGCs were cultured in vitro until colony formed.

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The cytochrome P4507B1 (P4507B1) in the human hippocampus is responsible for the production of 7alpha-hydroxylated derivatives of dehydroepiandrosterone (DHEA) and other 3beta-hydroxylated neurosteroids. Minor quantities of the 7beta-hydroxylated derivatives are also produced. Neuroprotective action of these 7-hydroxysteroids was reported.

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The equilibrium and kinetics of chlorophenol (CP) sorption by chitosan, poly D-glucosamine, were studied under simulated groundwater conditions. Lower temperature, from 25 degrees C to 15 degrees C and then 5 degrees C, markedly decreased the adsorption rates by a factor of 30-53% and 7-22%. Comparison between two types of chitosan, flakes and highly swollen beads, demonstrated that the maximum pentachlorophenol (PCP) uptake capacities in Langmuir and Freundlich models depend on the specific surface area of the particle.

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A neurodegenerative disease such as Alzheimer's disease (AD) is associated with significantly higher dehydroepiandrosterone (DHEA) levels in cerebrospinal fluid (CSF). Because the human brain is known to transform DHEA into DHEA sulfate (DHEAS), 7 alpha-hydroxy-DHEA, 7 beta-hydroxy-DHEA, and 16 alpha-hydroxy-DHEA, it is possible that DHEA accumulation in the brain results from a decreased production of such metabolites. To test this hypothesis, we have measured and compared CSF levels of DHEA, DHEAS, 7 alpha-hydroxy-DHEA, 7 beta-hydroxy-DHEA, and 16 alpha-hydroxy-DHEA in 14 patients with AD, 12 controls, and eight patients with another common dementia, vascular dementia (VD).

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The possibility of using waste Chinese cabbage (Brassica campestris) as a substrate for microbial biomass production was investigated. The juice from waste Chinese cabbage contains relatively high amounts of reducing sugars suitable for yeast culture. The cell mass and protein content of four species of yeast, Candida utilis, Pichia stipitis, Kluyveromyces marxianus, and Saccharomyces cerevisiae, were determined when cultured in juice extracted from cabbage waste.

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Liquid nitrogen (LN2) infusions are currently used in a slow controlled-rate freezing during cryopreservation. The effects of two different LN2 infusion frequencies (conventional, slow 50 infusions/min and high 120 infusions/min) were studied with frozen-thawed two-cell mouse embryos and their subsequent development to blastocysts. The embryos that were subjected to the high frequency LN2 infusion (HFLI) showed a significantly higher survival rate over the low frequency LN2 infusion (LFLI) (50.

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Several chitinases were expressed in a rice cell suspension culture and detected in the medium. One of them, designated as RCB4, was isolated 248 fold from the culture filtrate to homogeneity by 70% ammonium sulfate precipitation, DEAE-cellulose, CM-cellulose, Sephadex G-75 column chromatography, and native gel slicing. RCB4 had a molecular mass of 32 kDa by SDS-PAGE.

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Physical and chemical alterations caused by the freezing and thawing and their effects on survivals/developments in vitro were investigated. Of a total of 452 two-cell mouse embryos, the overall survival rate of the frozen-thawed embryos was 76.1% (344/452).

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