• The Korean Journal of Physiology
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• v.17 no.1
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• pp.63-69
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• 1983

This study was conducted to investigate the effect of prostaglandin $E_2(PGE_2)$ and indomethacin upon the electrical activity of the isolated cat stomach muscle strips$(1.5{\times}7.0\;cm)$. Fifty-seven muscle strips, obtained from 57 cat stomachs(including corpus and antrum) were studied in a muscle chamber filled with Krebs solution(pH 7.4, temperature $36{\pm}0.5^{\circ}C$) aerated with 5% $CO_2$ in $O_2$. The electrical activity was recorded by five capillary electrodes (Ag-AgCl), of which two were placed on the corpus and three on the antrum. After recording of the electrical activity in normal Krebs solution, $PGE_2$ in concentrations of 0.25(N=7), 0.5(=7), 1(N=7) and $2{\times}10^{-7}\;M(N=6)$ were administered to 27 muscle strips, while indomethacin was applied in concentretions of 0.25(N=9), 0.5(N=10), 1(N=6) and $2{\times}10^{-3}\;M(N=5)$ to the remaining 30 strips. The mean frequency were minutely measured from each electrogastrogram. 1) By adding $PGE_2$ in all doses, gastric slow wave frequency increased significantly compared with that in resting state. 2) Following $PGE_2$ administration, peak slow wave frequency increased dose-dependently. 3) After indomethacin addition in all doses, the slow wave frequency decreased significantly compared with that in resting state. 4) Following indomethacin administration, incidence of complete abolition of slow wave increased dose-dependently, and its latent period decreased also in a dose-dependent manner. It is inferred from the above results that prostaglandin $E_2$ has a facilitatory role in the development of gastric slow wave in cat.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.287-294
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• 2008

Three amino acid residues (His119, Glu164, and Glu338) in the active site of Thermus caldophilus GK24 ${\beta}$-glycosidase (Tca ${\beta}$-glycosidase), a family 1 glycosyl hydrolase, were mutated by site-directed mutagenesis. To verify the key catalytic residues, Glu164 and Glu338 were changed to Gly and Gln, respectively. The E164G mutation resulted in drastic reductions of both ${\beta}$-galactosidase and ${\beta}$-glucosidase activities, and the E338Q mutation caused complete loss of activity, confirming that the two residues are essential for the reaction process of glycosidic linkage hydrolysis. To investigate the role of His119 in substrate binding and enzyme activity, the residue was substituted with Gly. The H119G mutant showed 53-fold reduced activity on 5mM p-nitrophenyl ${\beta}$-D-galactopyranoside, when compared with the wild type; however, both the wild-type and mutant enzymes showed similar activity on 5mM p-nitrophenyl ${\beta}$-D-glucopyranoside at $75^{\circ}C$. Kinetic analysis with p-nitrophenyl ${\beta}$-D-galactopyranoside revealed that the $k_{cat}$ value of the H119G mutant was 76.3-fold lower than that of the wild type, but the $K_m$ of the mutant was 15.3-fold higher than that of the wild type owing to the much lower affinity of the mutant. Thus, the catalytic efficiency $(k_{cat}/K_m)$ of the mutant decreased to 0.08% to that of the wild type. The $k_{cat}$ value of the H119G mutant for p-nitrophenyl ${\beta}$-D-glucopyranoside was 5.l-fold higher than that of the wild type, but the catalytic efficiency of the mutant was 2.5% of that of the wild type. The H119G mutation gave rise to changes in optima pH (from 5.5-6.5 to 5.5) and temperature (from $90^{\circ}C\;to\;80-85^{\circ}C$). This difference of temperature optima originated in the decrease of H119G's thermostability. These results indicate that His119 is a crucial residue in ${\beta}$-galactosidase and ${\beta}$-glucosidase activities and also influences the enzyme's substrate binding affinity and thermostability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.133-138
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• 2006

To differentiate barley responses to drought and salt stress, barley seedlings at the second leaf stage were treated with 218 mM NaCl and 29.5% PEG6000 iso-osmotic to 218 mM NaCl for 6 days. Shoot fresh weight and leaf relative water content of barley seedlings were more reduced by drought compared to salt stress. Hydrogen peroxide content increased under both stress conditions, but its accumulation was more severe at 6 days after salt stress. The activity of ascorbate peroxidase, glutathione reductase (GR) and catalase (CAT) was enhanced until 4 days after salt stress. On the other hand, the activity of GR and CAT increased gradually until 6 days after drought. Among the amino acids measured in this study, the accumulation of glycine, arginine and GABA (${\gamma}-aminobutyric$ acid) was lower under salt stress than drought. However, considerably larger amount of proline was accumulated by salt stress. It is concluded that the antioxidant enzymes activity and amino acid content of barley seed-lings were differently regulated in response to the isoosmotic condition of salt and drought stress.

• Journal of Veterinary Clinics
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• v.23 no.4
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• pp.405-410
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• 2006

Using internal transcribed spacer 1 (ITS1) region ribosomal DNA sequences from 9 strains of Microsporum canis and 5 strains of Microsporum gypseum isolated from dogs and a cat with dermatophytosis, we demonstrated the mutual phylogenetic relationship of these strains. Nucleotide sequence analysis of the ITS 1 gene fragments from the 9 strains of M canis had the 100% nucleotide sequence similarities and the 5 strains of M gypseum also had the 100% nucleotide sequence similarities. The phylogenetic analysis of the nucleotide sequences of the 9 strains of M canis formed a nested cluster with the reference strains of M canis originating from USA, Australia, Japan, and Europe. M canis were genetically distinct from the other reference strains of Microsporum spp, but M distortum, M equinum, and M. ferrugineum were genetically very close to M canis. M gypseum from a cluster in the phylogenetic tree with M canis as an outgroup. The molecular analysis of ITS 1 genes provided the useful information for the identification of these microsporum species and the understanding of their relationship.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.296-301
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• 2005

The effect of aqueous methanol on the catalytic properties of porcine pancreatic lipase has been investigated. The k$_{CAT}$, values for the hydrolysis of N$^{alpha}$-benzyloxycarbonyl-L­lysine p-nitrophenyl ester at 0$^{circ}$C increased in a linear manner with increasing methanol concentration. However, the K$_{M}$ values were not influenced at methanol concentrations lower than $30\%$ and then began to increase at higher concentrations in an exponential fashion. Based on product analysis, the increase in k$_{CAT}$, with increasing methanol concentration can be accounted for by nucleophilic competition of methanol for the acyl enzyme intermediate, indicating that the rate-limiting step of the porcine pancreatic lipase-catalyzed reaction is deacylation under current experimental conditions. The exponential increase in K$_{M}$ at methanol concentrations higher than $30\%$ is attributed to the hydrophobic partitioning effect on substrate binding. There was no loss of lipase activity over a 4 h period in $60\%$ methanol concentration at pH$^{circ}$ 5.5 and 0$^{circ}$C. By monitoring the intrinsic fluorescence and absorbance, no evidence for structural changes by methanol was observed.

• Journal of Microbiology and Biotechnology
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• v.18 no.8
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• pp.1445-1452
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• 2008

An open reading frame (ORF) encoding a putative epoxide hydrolase (EHase) was identified by analyzing the genome sequence of Sphingophyxis alaskensis. The EHase gene (seh) was cloned and expressed in E. coli. To facilitate purification, the gene was fused in-frame to 6$\times$ histidine at the C-terminus. The recombinant EHase (rSEH) was highly soluble and could be purified to apparent homogeneity by one step of metal affinity chromatography. The purified SEH displayed hydrolyzing activities toward various epoxides such as styrene oxide, glycidyl phenyl ether, epoxyhexane, epoxybutane, epichlorohydrin, and epifluorohydrin. The optimum activity toward styrene oxide was observed at pH 6.5 and $35^{\circ}C$. The purified SEH showed a cold-adapted property, displaying more than 40% of activity at low temperature of $10^{\circ}C$ compared with the optimum activity. Despite the catalytic efficiency, the purified SEH did not hydrolyze various epoxides enantioselectively. $K_m$ and $k_{cat}$ of SEH toward (R)-styrene oxide were calculated as 4$\pm$0.3 mM and 7.42$s^{-1}$ respectively, whereas $K_m$ and $k_{cat}$ of SEH toward (S)-styrene oxide were 5.25$\pm$0.3 mM and 10.08$s^{-1}$ respectively.

• Journal of Veterinary Clinics
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• v.33 no.5
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• pp.304-306
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• 2016

A 12-month-old, 3.0-kg, male, Scottish fold cat was referred to Irion animal hospital with dyspnea and cardiac murmur. In radiograph, right-sided cardiomegaly and pleural effusion were identified. In echocardiographic examination, abnormal stenotic region was identified in right ventricle and dilation of right atrium and concentric hypertrophy of interventricular septum and the free wall of right ventricle were also identified. In the stenotic region, abnormal muscular band was identified. The turbulent flow was identified in infundibular region of right ventricular outflow tract with color-Doppler examination and high velocity flow (4.0 m/s) was also identified in stenotic region. With these results, double-chambered right ventricle (DCRV) was diagnosed.

• Reproductive and Developmental Biology
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• v.33 no.1
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• pp.49-54
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• 2009

The current study was designed to evaluate the effects of the reactive oxygen species (ROS) generated with a xanthine (X) and xanthine oxidase system (XO) on sperm function and DNA fragmentation in porcine spermatozoa. ROS were produced by a combination of $1,000{\mu}M$ X and 50 mU/ml XO. The ROS scavengers such as superoxide dismutase (SOD) (200 U/ml) and catalase (CAT) (500 U/ml) were also tested. Spermatozoa were incubated for 2 hours in BWW medium with a combination of X-XO supplemented with or without antioxidants at $37^{\circ}C$ under 5% $CO_2$ incubator. Ca-ionophore-induced acrosome reaction, the proportion of swollen spermatozoa under hypo-osmotic condition, malondialdehyde formation for the analysis of lipid peroxidation, and the proportion of DNA fragmentation were determined after 2 hours incubation. The action of ROS on porcine spermatozoa resulted in decreased Ca-ionophore-induced acrosome reaction and membrane integrity, increased the formation of malondialdehyde, and the proportion of sperm with DNA fragmentation(p<0.05). The toxic effects caused by ROS were completely alleviated by CAT in terms of sperm function and characteristics, however SOD did not serve the same scavenger effect as CAT. To conclude, the ROS can cause significant damage to porcine sperm functions and characteristics, which can be minimized by the use of antioxidants.

• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.11-14
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• 2003

10GBASE-T is 10Gigabit Ethernet over horizontal structured, twisted-pair copper cabling.(1) It aims to transmit data at a speed of 10Gbps at a l00m distance away, through UTP (unshielded twisted -pair) Cat-5e cable 4-pair. This paper looks over the characteristic of media over Cat 5e, 6, 7, and then suggests how much noise should be removed from it in order to offer the transmission speed of 10Gbps as sending data through each physical medium.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.666-668
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• 2018

최근 반려동물을 키우는 가구 수의 증가와 함께, 반려묘에 대한 관심도 상당히 증가하고 있다. 특히 반려인은 반려묘와의 원활한 의사소통과 교감을 바라지만 반려묘의 세세한 감정 상태를 24시간 내내 파악하는 것은 어려운 일이다. 본 논문에서는 반려묘의 울음소리에 많은 감정 및 상태 정보가 담겨있는 것에 착안하여, 반려묘의 울음소리를 기반으로 감정을 분류하는 시스템을 제안한다. 제안된 시스템은 먼저, 이미 수집된 소리 데이터를 데이터 증폭 방법론을 이용하여 데이터를 확장 한 후, 해당 소리들의 멜 스펙트로그램 정보를 추출한다. 이를 시계열 정보 처리에 효과적인 LSTM에 적용하여 반려묘의 감정 상황을 식별할 수 있도록 학습을 수행한다. 실험 결과, 반려묘의 감정 상태 분류의 가능성을 확인하였다.