• Journal of the Korean Society of Radiology
• /
• v.84 no.3
• /
• pp.745-749
• /
• 2023

Gerstmann-Sträussler-Scheinker (GSS) disease is a rare hereditary prion disease which is clinically characterized by a progressive cerebellar ataxia followed by cognitive impairment. We report a rare case of GSS disease in a 39-year-old male patient who complained of a progressive gait disturbance followed by dysarthria with cognitive impairment, after five months from the onset of initial symptom. His brain MRI scan revealed multifocal symmetric diffusion restricted lesions with T2/FLAIR hyperintensities in bilateral cerebral cortices, basal ganglia, and thalami. His family members also manifested similar symptoms in their 40-50s, suggesting the possibility of a genetic disease. Finally, he was genetically diagnosed with GSS disease by real-time quaking-induced conversion and prion protein (PRNP) gene sequencing test.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.5
• /
• pp.573-580
• /
• 2005

Cholesterol $7\alpha-hydroxylase$ (CYP7A1) is the rate-limiting enzyme in the conversion of cholesterol to bile acids and plays a central role in regulating cholesterol homeostasis. We previously showed that a fermentable $\beta-glucan$ ingestion decreased plasma cholesterol levels due to fecal bile acid excretion elevation involved inincrease of cholesterol $7\alpha-hydroxylase$ mRNA expression and activity. It is proposed that short chain fatty acids (SCFA) produced by cecal and colonic fermentation of soluble fiber are associated with cholesterol-lowering effect of fiber. In the present study, we investigated whether CYP7A1 expression is up-regulated by short chain fatty acids or by hormones in cultured human hepatoma (HepG2) cells. Confluent HepG2 cell were incubated with acetate, propionate, or butyrate at 1 mM concentration for 24 hrs. Acetate as well as propionate increased to 1.8-fold expression of CYP7A1 mRNA than the control. Butyrate also increased 1.5-fold expression of CYP7A1 mRNA. Our data show for the first time that SCFA increase expression of CYP7A1 mRNA. Adding insulin, dexamethasone and triiodothyronine $(1\;{\mu}M)$ to HepG2 cell increased the expression of CYP7A1 mRNA to $150\%,\;173\%,\;141\%$, respectively. These results suggest that SCFA produced by cecal fermentation stimulate enteric nervous system, in which secreted some neuropeptides may be responsible for change in cholesterol and bile acid metabolism. These findings suggest that SCFA are involved in lowering plasma cholesterol levels due to the up-regulation of CYP7A1 and bile acid synthesis.

• Journal of Life Science
• /
• v.22 no.4
• /
• pp.559-564
• /
• 2012

In order to investigate the effect of phytochromes on the regulation of ethylene biosynthesis, we measured the ethylene production and the activities of enzymes involved in ethylene biosynthesis using phytochrome mutants such as $phyA$, $phyB$, and $phyAB$ of Arabidopsis. The ethylene production was decreased in mutants grown in white light. In particular, double mutants showed a 37% decrease compared to the wild type in ethylene production. When Arabidopsis roots were grown in the dark, mutants did not show a decrease in ethylene production; however, production was significantly decreased in the double mutant grown in red light. Only $phyB$ did not show the decrease in the ethylene production in far-red light. Unlike the ACO activities, the ACS activities of mutants showed the same pattern as the ethylene production under several light conditions. The results of ACS activities confirmed the expression of the ACS gene by RT-PCR analysis. The decrease of ethylene production in mutants was due to the lower activity of ACC synthase, which converts the S-adenosyl-L-methionine (AdoMet) to 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor of ethylene. These results suggested that both phytochrome A and B play an important role in the regulation of ethylene biosynthesis in Arabidopsis roots in the conversion step of AdoMet to ACC, which is regulated by ACS.

• Korean Journal of Microbiology
• /
• v.49 no.4
• /
• pp.369-376
• /
• 2013

We isolated the ${\beta}$-glucosidase producing bacteria (BGB) in ginseng root system (rhizosphere soil, rhizoplane, inside of root). Phylogenetic analysis of the 28 BGB based on the 16S rRNA gene sequences, BGB from rhizosphere soil belong to genus Stenotrophomonas (3 strains), Bacillus (1 strain), and Pseudoxanthomonas (1 strain). BGB isolates from rhizoplane were Stenotrophomonas (16 strains), Streptomyces (1 strain) and Microbacterium (1 strain). BGB from inside of root were categorized into Stenotrophomonas (3 strains) and Lysobacter (2 strains). Especially, Stenotrophomonas comprised the largest portion (approximately 90%) of total isolates and Stenotrophomonas was a dominant group of the ${\beta}$-glucosidase producing bacteria. We selected strain 4KR4, which had high ${\beta}$-glucosidase activity (108.17 unit), could transform ginsenoside Rb1 into Rd, Rg3, and Rh2 ginsenosides. In determining its relationship on the basis of 16S rRNA sequence, 4KR4 strain was most closely related to Stenotrophomonas rhizophila e-$p10^T$ (AJ293463) (99.62%). Therefore, on the basis of these polyphasic taxonomic evidence, the ginsenoside Rb1 converting bacteria 4KR4 was identified as Stenotrophomonas sp. 4KR4 (=KACC 17635).

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.5
• /
• pp.788-801
• /
• 2020

Objective: This study was conducted to evaluate the effects of diets containing different wet rice distillers' by-product (RDP) levels on growth performance, nutrient digestibility, blood profiles and gut microbiome of weaned piglets. Methods: A total of 48 weaned castrated male crossbred pigs, initial body weight 7.54±0.97 kg, and age about 4 wks, were used in this experiment. The piglets were randomly allocated into three iso-nitrogenous diet groups that were fed either a control diet, a diet with 15% RDP, or a diet with 30% RDP for a total of 35 days. Chromium oxide was used for apparent digestibility measurements. On d 14 and d 35, half of the piglets were randomly selected for hemato-biochemical and gut microbiota evaluations. Results: Increasing inclusion levels of RDP tended to linearly increase (p≤0.07) average daily gain on d 14 and d 35, and decreased (p = 0.08) feed conversion ratio on d 35. Empty stomach weight increased (p = 0.03) on d 35 while digestibility of diet components decreased. Serum globulin concentration decreased on d 14 (p = 0.003) and red blood cell count tended to decrease (p = 0.06) on d 35, parallel to increase RDP levels. Gene amplicon profiling of 16S rRNA revealed that the colonic microbiota composition of weaned pigs changed by inclusion of RDP over the period. On d 14, decreased proportions of Lachnospiraceae_ge, Ruminococcaceae_ge, Ruminococcaceae_UCG-005, and Bacteroidales_ge, and increased proportions of Prevotellaceae_ge, Prevotella_2, and Prevotella_9 were found with inclusion of RDP, whereas opposite effect was found on d 35. Additionally, the proportion of Lachnospiraceae_ge, Ruminococcaceae_ge, Ruminococcaceae_UCG-005, and Bacteroidales_ge in RDP diets decreased over periods in control diet but increased largely in diet with 30% RDP. Conclusion: These results indicate that RDP in a favorable way modulate gastrointestinal microbiota composition and improve piglet performance despite a negative impact on digestibility of lipids and gross energy.

• Biomolecules & Therapeutics
• /
• v.15 no.1
• /
• pp.16-26
• /
• 2007

Tissue plasminogen activator (tPA) is a serine protease catalyzing the proteolytic conversion of plasminogen into plasmin, which is involved in thrombolysis. During last two decades, the role of tPA in brain physiology and pathology has been extensively investigated. tPA is expressed in brain regions such as cortex, hippocampus, amygdala and cerebellum, and major neural cell types such as neuron, astrocyte, microglia and endothelial cells express tPA in basal status. After strong neural stimulation such as seizure, tPA behaves as an immediate early gene increasing the expression level within an hour. Neural activity and/or postsynaptic stimulation increased the release of tPA from axonal terminal and presumably from dendritic compartment. Neuronal tPA regulates plastic changes in neuronal function and structure mediating key neurologic processes such as visual cortex plasticity, seizure spreading, cerebellar motor learning, long term potentiation and addictive or withdrawal behavior after morphine discontinuance. In addition to these physiological roles, tPA mediates excitotoxicity leading to the neurodegeneration in several pathological conditions including ischemic stroke. Increasing amount of evidence also suggest the role of tPA in neurodegenerative diseases such as Alzheimer's disease and multiple sclerosis even though beneficial effects was also reported in case of Alzheimer's disease based on the observation of tPA-induced degradation of $A{\beta}$ aggregates. Target proteins of tPA action include extracellular matrix protein laminin, proteoglycans and NMDA receptor. In addition, several receptors (or binding partners) for tPA has been reported such as low-density lipoprotein receptor-related protein (LRP) and annexin II, even though intracellular signaling mechanism underlying tPA action is not clear yet. Interestingly, the action of tPA comprises both proteolytic and non-proteolytic mechanism. In case of microglial activation, tPA showed non-proteolytic cytokine-like function. The search for exact target proteins and receptor molecules for tPA along with the identification of the mechanism regulating tPA expression and release in the nervous system will enable us to better understand several key neurological processes like teaming and memory as well as to obtain therapeutic tools against neurodegenerative diseases.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.3
• /
• pp.416-423
• /
• 2020

Objective: This study examined the effects of divergence in residual feed intake (RFI) on expression profiles of key genes related to lipid transport in the liver and duodenal epithelium and their associations with feed efficiency traits in meat-type ducks. Methods: A total of 1,000 male ducks with similar body weight (1,042.1±87.2 g) were used in this study, and their individual RFI was calculated from 21 to 42 d of age. Finally, the 10 highest RFI (HRFI) and 10 lowest RFI (LRFI) ducks were chosen for examining the expression of key genes related to lipid transport in the liver and duodenal epithelium using quantitative polymerase chain reaction. Results: In the liver, expression levels of albumin (ALB), CD36 molecule (CD36), fatty acid hydroxylase domain containing 2 (FAXDC2), and choline kinase alpha (CHKA) were significantly higher in LRFI ducks than in HRFI ducks (p<0.01); negative correlations (p<0.05) between expression levels of ALB, CD36, FAXDC2, and CHKA and RFI were detected in the liver. Additionally, ALB expression was strongly positively correlated (p<0.05) with CD36, FAXDC2, CHKA, and apolipoprotein H (APOH) expression in the liver. In duodenal epithelium, we found that mRNA levels of ALB, CD36, FAXDC2, and APOH were significantly higher in LRFI ducks than in HRFI ducks (p<0.01); RFI was strongly negatively correlated (p<0.05) with ALB, FAXDC2, and APOH expression, while ALB expression was strongly positively correlated with APOH expression (p<0.01) in duodenal epithelium. Furthermore, expression levels of both ALB and FAXDC2 genes were significantly associated with feed conversion ratio and RFI in both liver and duodenal epithelium (p<0.05). Conclusion: Our findings therefore suggest that ALB and FAXDC2 genes might be used as potential gene markers designed to improve feed efficiency in future meat-type duck breeding programs.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.4
• /
• pp.606-612
• /
• 2018

The enzyme xylose isomerase (E.C. 5.3.1.5, XI) is responsible for the conversion of an aldose to ketose, especially xylose to xylulose. Owing to the ability of XI to isomerize glucose to fructose, this enzyme is used in the food industry to prepare high-fructose corn syrup. Therefore, we studied the characteristics of XI from Anoxybacillus kamchatkensis G10, a thermophilic bacterium. First, the gene coding for XI (xylA) was inserted into the pET-21a(+) expression vector and the construct was transformed into the Escherichia coli competent cell BL21 (DE3). The expression of recombinant XI was induced in the absence of isopropyl-thio-${\beta}$-galactopyranoside and purified using Ni-NTA affinity chromatography. The optimum temperature of recombinant XI was $80^{\circ}C$ and measurement of the heat stability indicated that 55% of residual activity was maintained after 2 h incubation at $60^{\circ}C$. The optimum pH was found to be 7.5 in sodium phosphate buffer. Magnesium, manganese, and cobalt ions were found to increase the enzyme activity; manganese was the most effective. Additionally, recombinant XI was resistant to the presence of $Ca^{2+}$ and $Zn^{2+}$ ions. The kinetic properties, $K_m$ and $V_{max}$, were calculated as 81.44 mM and $2.237{\mu}mol/min/mg$, respectively. Through redundancy analysis, XI of A. kamchatkensis G10 was classified into a family containing type II XIs produced by the genera Geobacillus, Bacillus, and Thermotoga. These results suggested that the thermostable nature of XI of A. kamchatkensis G10 may be advantageous in industrial applications and food processing.

• Journal of Ginseng Research
• /
• v.42 no.1
• /
• pp.116-121
• /
• 2018

Background: Black ginseng (BG) has greatly enhanced pharmacological activities relative to white or red ginseng. However, the effect and molecular mechanism of BG on muscle growth has not yet been examined. In this study, we investigated whether BG could regulate myoblast differentiation and myotube hypertrophy. Methods: BG-treated C2C12 myoblasts were differentiated, followed by immunoblotting for myogenic regulators, immunostaining for a muscle marker, myosin heavy chain or immunoprecipitation analysis for myogenic transcription factors. Results: BG treatment of C2C12 cells resulted in the activation of Akt, thereby enhancing hetero-dimerization of MyoD and E proteins, which in turn promoted muscle-specific gene expression and myoblast differentiation. BG-treated myoblasts formed larger multinucleated myotubes with increased diameter and thickness, accompanied by enhanced Akt/mTOR/p70S6K activation. Furthermore, the BG treatment of human rhabdomyosarcoma cells restored myogenic differentiation. Conclusion: BG enhances myoblast differentiation and myotube hypertrophy by activating Akt/mTOR/p70S6k axis. Thus, our study demonstrates that BG has promising potential to treat or prevent muscle loss related to aging or other pathological conditions, such as diabetes.

• Development and Reproduction
• /
• v.10 no.2
• /
• pp.127-133
• /
• 2006

[ $17\;{\alpha}-hydroxylase/17,20-lyase(P450_{C17})$ ] is the key enzyme mediating the conversion of progesterone to $17\;{\alpha}-hydroxyprogesterone$, ultimately to androstenedione during steroidogenesis. R. dybowskii's ovarian $P450_{C17}$ cDNA was cloned to understand the regulatory mechanism of ovarian steroidogenic pathway at the molecular level in amphibian. A 2.5kb cDNA clone encoding a single open-reading frame with a 519 deduced amino acid was isolated with the screening of ovarian cDNA library. This sequence contained the three highly conserved domains as seen in $P450_{C17}$ of other species. The comparison of amino acid sequence of Rana $P450_{C17}$ with other animal's $P450_{C17}$ showed relatively high identity with 76% in Xenopus, 63% in chicken, 60% in rainbow trout, and 45% in human. Phylogenic analysis also indicated that Rana $P450_{C17}$ gene was evolutionary well conserved among vertebrate. Northern analysis indicated that the two different sizes of $P450_{C17}$ transcripts with approximately 2.5 and 3.6kb were detected in ovary tissue, but not in other tissues. The expression vector of Rana $P450_{C17}$ clearly showed the $17\;{\alpha}-hydroxylase$ activity converting the exogenous progesterone into $17\;{\alpha}-hydroxyprogesterone$ in the nonsteroidogenic COS-1 cells. Therefore, Rana $P450_{C17}$ cDNA is very useful to investigate the molecular mechanism of the ovarian steroidogenesis in amphibian.