• Radiation Oncology Journal
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• v.21 no.1
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• pp.66-74
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• 2003

Purpose : The matrix metalloprotelnases (MMPs) are a family of enzymes whose main function is the degradation of the extracellular matrix. Several studies have revealed that MMPs and TIMPS are related to the wound heating process and in photoaging caused by ultraviolet Irradiation. However, the expressions of MMP and TIMP after irradiation have not, to the best of our knowledge, been studied. This study investigates the expressions of MMP-2 and TIMP-2 in rat Intestinal mucosa following irradiation. Materials and Methods : The entire abdomen of Sprague-Dawley rats was irradiated using a single dose method. The rats were sacrificed on day 1, 2, 3, 5, 7 and 14 following irradiation. Histopathological observations were made using hematoxilin & eosin staining. The expressions of MMP-2 and TIMP-2 were examined using immunohistochemistry, Irnrnunoblotting and ELISA. Results : Radiation induced damage associated with atrophic villi, and infiltration of inflammatory cell was observed from the first postirradiation day, and severe tissue damage was observed on the second and the third postirradiation days. An increase in mitosis and the number of regenerating crypts, as evidence of regeneration, were most noticeable on the fifth postirradiation day. From the immunohistochemlstry, the MMP-2 expression was observed from the first postirradiation day, but was most conspicuous on the third and the fifth postirradiation days. The TIMP-2 expression was most conspicuous on the fifth postirradiation day. From the irnrnunoblotting, the MMP-2 expression was strongly positive on the third postirradlatlon day, and that of TIMP-2 showed a strong positive response on the fifth postirradiation day. In ELISA tests, the expressions of MMP-2 and TIMP-2 were increased in the postirradiation groups compared to those of the normal controls, and showed a maximum increase on the fifth postirradiatlon day. These results were statistically significant. Conclusion : The expressions of MMP-2 and TIMP-2 were increased in the intestinal mucosa of the rats following irradiation, and these results correlated with the histopathological findings, such as tissue damage and regeneration. Therefore, this study suggests that MMP-2 and TIMP-2 play roles in the mechanisms of radiation-induced damage and regeneration of intestinal mucosa of rats.

• Korean Journal of Microbiology
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• v.41 no.2
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• pp.99-104
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• 2005

Corynebacterial clones which exert regulatory effects on the expression of the glyoxylate bypass genes were isolated using a reporter plasmid carrying the enteric lacZ fused to the aceB promoter of Corynebacterium glutamicum. Some clones carried common fragments as turned out by DNA mapping technique. Subcloning analysis followed by the measurement of $\beta-galactosidase$ activity in Escherichia coli identified the region responsible for the aceB-repressing activity. Sequence analysis of the DNA fragment identified two independent ORFs of ORF1 and ORF2. Among them, ORF2 was turned out to be responsible for the aceB-repressing activity. ORF1 encoded a 23,216 Da protein composed of 206 amino acids. Sequence similarity search indicated that the ORF may encode a ECF-type $\sigma$ factor and designated sigH. To identify the function of sigH, C. glutamicum sigH mutant was constructed by gene disruption technique and the sigH mutant showed growth retardation as compared to the wild type strain. In addition, the mutant strain showed sensitivity to oxidative-stress generating agent plumbagin. This result imply that sigH is probably involved in the stress response occurring during normal cell growth.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.40-46
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• 2006

Galactose joined to glucose by a $\beta(1\rightarrow4)$ glycosidic bond makes lactose and this disaccharide is rich in milk. It is known that lacotse is hydrolyzed to each monomeric sugar by either lactase in human or $\beta-galactosidase$ in bacteria. Ingestion of milk by lactase-deficient persons causes a temporary diarrhea and subsequent chronic diarrhea results in colitis with chronic inflammation. We isolated a $\beta-galactosidase$ producing psycrotolerant strain AS-20 from near cattle shed and investigated the growth at various temperature conditions. Whereas Escherichia coli strains did not grow at $10^{\circ}C$, the AS-20 strain could grow well at this low temperature and showed optimal growth at $30^{\circ}C$. The isolated strain was identified as 97% Hafnia alvei by biochemical properties. This strain could ferment glucose, lacotse, maltose, mannitol, xylose, ONPG, rhamanose and L-arabinose, and decarboxylate lysin and ornithine. To confirm the identity of isolated strain we amplified 16S rDNA by PCR and searched similarity of the 1426 bp DNA sequcence with Genbank database. The strain AS-20 showed 99% similarity with Hafnia alvei. The activity of $\beta-galactosidase$ was 1.5 times higher when the cell was grown at 10 or $20^{\circ}C$ than at $30^{\circ}C$. The highest enzyme activity of AS-20 was also much higher than that of E. coli, which was grown at $30^{\circ}C$.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.109-115
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• 2012

Helicobacter pylori is an important factor of chronic gastritis, digestive ulcer, and stomach cancer. CagL, a virulence factor of H. pylori, is well-known as a pilus protein which acts as adhesion to host cell and a component of Type 4 secretion system. In this study, we evaluated the protective response of recombinant CagL protein (rCagL) using Mongolian gerbil animal model for H. pylori infection. The cagL gene was cloned from 26695 H. pylori followed by over-expression and purification of the protein in E. coli. Mongolian gerbils were immunized with rCagL protein mixed with aluminum adjuvant via intramuscular injections once a week during 4 weeks. At a week after the last immunization, the Mongolian gerbils were administrated with H. pylori 7.13 strain into the stomach and sacrificed to measure antibody titer on rCagL by ELISA and bacterial colonization in the stomach, and to examine the histopathological changes and cytokine expression at 6 week after challenge. Antibody titers on recombinant protein were significantly increased from a week after the first immunization. There was no significant change of the number of bacterial colony between control group and immunized group. The relative stomach weight was significantly decreased in immunized group, but the significant change of histopathological assessment was not observed in the stomach. Cytokine expression such as IL-$1{\beta}$ and KC also was not significantly different between control and immunized groups. These results indicate that rCagL could effectively induce the formation of the specific IgG antibodies. However, bacterial colonization and histopathological lesions could not be inhibited by the immunization in the stomach, indicating not enough protection against H. pylori infection. We consider that along with CagL other adequate antigens could be needed stimulating immune response and inducing protective effects against gastric disease, and also a better adjuvant could be considered.

• KSBB Journal
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• v.22 no.5
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• pp.297-304
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• 2007

For large and rapid screening of high-yielding mutants of lovastatin produced by filamentous fungal cells of Aspergillus terreus, one of the most important stage is to test as large amounts of mutated strains as possible. For this purpose, we intended to develop a miniaturized cultivation method using $7m{\ell}$ culture tube instead of traditional $250m{\ell}$ flask (working volume $50m{\ell}$). For obtaining large amounts of conidiospores to be used as inoculums for miniaturized cultures, 4 components i.e., glucose, sucrose, yeast extract and $KH_2PO_4$ were intensively investigated, which had been observed to show positive effect on enhancement of spore production through Plackett-Burman design experimet. When optimum concentrations of these components that were determined through application of response surface method (RSM) based on central composite design (CCD) were used, maximum spore numbers amounting to $1.9\times10^{10}$ spores/plate were obtained, resulting in approximately 190 fold increase as compared to the commonly used PDA sporulation medium. Using the miniaturized cultures, intensive strain development programs were carried out for screening of lovastatin high-yielding as well as highly reproducible mutants. It was observed that, for maximum production of lovastatin, the producers should be activated through 'PaB' adaptation process during the early solid culture stage. In addition, they should be proliferated in condensed filamentous forms in miniaturized growth cultures, so that optimum amounts of highly active cells could be transferred to the production culture-tube as reproducible inoculums. Under these highly controlled fermentation conditions, compact-pelleted morphology of optimum size (less than 1 mm in diameter) was successfully induced in the miniaturized production cultures, which proved essential for maximal utilization of the producers' physiology leading to significantly enhanced production of lovastatin. As a result of continuous screening in the miniaturized cultures, lovastatin production levels of the 81% of the daughter cells derived from the high-yielding producers turned out to be in the range of 80%$\sim$120% of the lovastatin production level of the parallel flask cultures. These results demonstrate that the miniaturized cultivation method developed in this study is efficient high throughput system for large and rapid screening of highly stable and productive strains.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.131-142
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• 1989

As a part of investigation for utilizing anchovy more effectively as a food source, this work was undertaken the changes in keeping quality and taste compounds in the extracts from rapid fermented anchovy sauce during storage at room temperature. Rapid fermented products was made of chopped anchovy, water, koji and soybean protein isolate (20:10:2:1, w/w) thorough hydroxazine for 6 hours at $50^{\circ}C$. The liquified anchovy sauce extracts, contained 15% salt(w/w), were stored for 60 days at room temperature. The changes in pH, acidity, amino nitrogen and contents of taste compounds of the products were negligible during storage. The viable cell counts and histamines of the products were less than 30(colony/e extracts), 7.2-21.8(mg/100g extracts) during storage predominant free amino acids showed in the extracts from products were alanine, glutamic acid, histidine, lysine, leucine, valine and the total contents of those free amino acids were 60.4-64.3% of total free amino acids at final stage of storage. The major nucleotides and their related compounds of the products were revealed hypoxanthine, which were 69% over the total nucleotides and their related compounds. Using the omission test, the major taste compounds in the products were revealed free amino acids, nucleotides and their related compounds. The non-volatile organic acids, total creatinine, betaine, and TMAO were seemed to act an auxiliary role in taste of the extracts from rapid fermented anchovy sauce.

• Pediatric Infection and Vaccine
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• v.27 no.2
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• pp.102-110
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• 2020

Purpose: This study aimed to investigate the clinical characteristics of human parechovirus (HPeV) infection in sepsis-like syndrome in infants aged under 3 months. Methods: Medical records of infants aged under 3 months with sepsis-like symptoms who were admitted between July 1, 2018 and August 31, 2018 were reviewed. A multiplex reverse transcription-polymerase chain reaction panel test was performed on the cerebrospinal fluid (CSF). Thirty-nine enrolled infants were categorized into three groups: 11 in group 1 (HPeV detected in the CSF), 13 in group 2 (enterovirus detected in the CSF), and 15 in group 3 (no virus detected in the CSF). Results: Compared with groups 2 and 3, a higher proportion of group 1 had tachycardia, tachypnea, apnea, and hypotension (P<0.05). A significantly lower white blood cell (WBC) count was noted in group 1 than in groups 2 and 3 (5,622±2,355/μL, 9,397±2,282/μL, and 12,312±7,452/μL, respectively; P=0.005). The CSF WBC count was lower in group 1 than in groups 2 and 3 (0.9±1.7/μL, 85.1±163.6/μL, and 3.7±6.9/μL, respectively; P=0.068). The proportion of patients requiring inotrope support (36.6% vs. 0% and 6.6%), mechanical ventilation (18.1% vs. 0% and 0%), and high flow nasal cannula (45.4% vs. 15.3% and 6.6%) was higher in group 1 than in groups 2 and 3. All patients recovered completely without complications. Conclusions: HPeV infection shows a severe clinical course and can cause a severe sepsis-like syndrome in infants aged under 3 months. Early diagnosis and proper treatment of HPeV infection are required.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.3
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• pp.151-157
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• 2015

Recent laboratory studies have documented that mixotrophic dinoflagellates Dinophysis spp. and heterotrophic dinoflagellate Oxyphysis oxytoxoides share a common prey, i.e. the mixotrophic ciliate Mesodinium rubrum. Nonetheless, very little is known about the population dynamics and species interactions among these protists in natural environments. To investigate the interactions between the dinoflagellate predators and their ciliate prey in the field, we took the samples twice a day from 26 July to 28 August, 2011 at a fixed station in Masan Bay and analyzed their abundances. During this study, salinity was highly variable, ranging from 5 to 28, due to the periodic input of rainfalls to the sampling station. Water temperature was on average $26.5^{\circ}C$ until 20 August and thereafter was about $21^{\circ}C$ by the end of the sampling period. The ciliate M. rubrum occurred persistently throughout the sampling period, ranging from 13 to $492\;cells\;mL^{-1}$. Cell densities of D. acuminata and O. oxytoxoides ranged from undetectable level to $19,833\;cells\;L^{-1}$ and from undetectable level to $100,333\;cells\;L^{-1}$, respectively. The high abundance of D. acuminata mostly followed the blooming of the ciliate M. rubrum, but it often did not peak even during heavy blooms of the prey, probably due to sensitivity to large salinity fluctuation and also presumably overlapped grazing by other mixotrophic dinoflagellates. The abundance of O. oxytoxoides was detected only when water temperature was lower than $24^{\circ}C$, indicating that water temperature is an important environmental factor to control the population dynamics of the dinoflagellate species.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.466-477
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• 2018

In this study, the anti-inflammatory activities of the extracts of different parts of Hovenia dulcis such as leaves, stems, and roots were investigated. Among them, the roots extract (RE) showed the most potent suppressive effect against pro-inflammatory mediators in LPS-stimulated mouse macrophage cells. RE induced dose-dependent reduction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and concomitantly reduced the production of NO and $PGE_2$. Additionally, pre-treatment with RE significantly suppressed the production of inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin $(IL)-1{\beta}$, and IL-6, as well as mRNA levels. Moreover, phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear translocation of nuclear factor-kappa B (NF-kB) were also strongly attenuated by RE in RAW264.7 cell. Furthermore, RE induced HO-1 expression through nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and increase HO-1 activity in RAW264.7 macrophages. Therefore, these results indicate that RE strongly inhibits LPS-induced inflammatory responses by blocking NF-kB activation, inhibiting MAPKs phosphorylation, and enhancing HO-1 expression in macrophages, suggesting that RE of H. dulicis and a major component, 27-O-protocatechuoylbetulinic acid could be applied as a valuable natural anti-inflammatory material.

• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.239-255
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• 1997

Expression of the cDNA of the VP1 gene on the genome RNA B segment of infectious pancreatic necrosis virus (IPNV) DRT strain in E. coli and a recombinant baculovirus were carried out. The VP1 gene in the pMal-pol clone (Lee et al. 1995) was cleaved with XbaI and transferred into baculovirus transfer vector, pBacPAK9 and it was named pBacVP1 clone. The VP1 gene in the pBacVP1 clone was double-digested with SacI and PstI and then inserted just behind T5 phage promoter and the $6{\times}His$ region of the pQE-3D expression vector, and it was called pQEVPl. Again, the $6{\times}$His-tagged VP1 DNA fragment in the pQEVP1 was cleaved with EcoRI and transferred into the VP1 site of the pBacVP1, resulting pBacHis-VP1 recombinant. The pBacHis-VP1 DNA was cotransfected with LacZ-Hyphantria cunea nuclear polyhedrosis virus (LacZ-HcNPV) DNA digested with Bsu361 onto S. frugiperda cells to make a recombinant virus. One VP1-gene inserted recombinant virus was selected by plaque assay. The recombinant virus was named VP1-HcNPV-1. The $6{\times}$His-tagged VP1 protein produced by the pQEVP1 was purified with Ni-NTA resin chromatography and analyzed by SDS-PAGE and Western blot analysis. The molecular weight of the VP1 protein was 94 kDa. The recombinant virus, VP1-HcNPV-1 did not form polyhedral inclusion bodies and expressed VP1 protein with 95 kDa in the infected S. frugiperda cells, which was detected by Western blot. The titer of the VP1-HcNPV-1 in the first infected cells was $2.0{\times}10^5\;pfu/ml$ at 7 days postinfection.