• Korean Journal of Veterinary Research
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• v.58 no.2
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• pp.95-98
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• 2018

Brucellosis is one of the common zoonoses caused by Brucella abortus (B. abortus). However, little has been reported on factors affecting invasion of B. abortus into host cells. To investigate cell-type dependent invasion of B. abortus, phagocytic RAW 264.7 and THP-1 cells and non-phagocytic HeLa cells were infected with wild-type and mutant B. abortus, and their invasion efficiencies were compared. The invasion efficiencies of the strains were cell-type dependent. Wild-type B. abortus invasion efficiency was greater in phagocytic cells than in epithelial cells. The results also indicated that there are different factors involved in the invasion of B. abortus into phagocytic cells.

• The Journal of Information Systems
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• v.14 no.2
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• pp.25-53
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• 2005

To overcome rapidly changing business environment, companies are focusing on their core business areas. Outsourcing in general has become a standard to sustain competitive advantage. ASP(Application Service Provider) service, another form of IT outsourcing, is business model for providing a contractual service offering to deploy, host, manage and rent access to an application from a centrally managed facility. The main purpose of this study is to investigate on the factors contributing to the success of ASP services by conducting an empirical research to enterprises using ASP service. For this purpose, we developed a research model based on the literature reviews of ASP services, IT outsourcing, and relational exchange. A total of 106 usable survey responses has been used in the analysis. The unit of analysis was relationship and respondents were person in charge of ASP service of each corporation. The findings indicates that (1) service tangibles, customization, partnership, IS maturity and monitoring of the vendor had an positive influence upon non-economic benefits, (2) service tangibles, IS maturity and monitoring of the vendor had an positive influence upon economic benefits, and (3) service tangibles, reliability, partnership and monitoring of the vendor had positive influence upon satisfaction about outcomes of relationships.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.1
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• pp.37-49
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• 2013

This paper investigates social networks of high technology firms, located in a newly developed industrial area, called 'Daedeok Technovalley' in Daejeon, Korea. While the Vally was developed as an extension of Daedeok Science Park in Daejeon, it host 400 or so technology-intensive firms. A questionnaire survey was conducted to collect data on the firms of the Vally, during January 2010, and obtained 201 completed questionnaires. Additional data, such as sales amount and employment, were collected to measure the changes of firm size. This research analysed these data to argue that the enterprises have established some networks with local institutions; however, the networks do not significantly affect on the growth of the firms.

• Journal of Yeungnam Medical Science
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• v.34 no.2
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• pp.149-160
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• 2017

Streptococcus pneumoniae, pneumococcus, is the most common cause of community-acquired pneumonia (CAP). CAP is an important infectious disease with high morbidity and mortality, and it is still one of the leading causes of death worldwide. Many genetic factors of the host and various environmental factors surrounding it have been studied as important determinants of the pathophysiology and outcomes of pneumococcal infections. Various cytokines, including transforming growth factor $(TGF)-{\beta}1$, are involved in different stages of the progression of pneumococcal infection. $TGF-{\beta}1$ is a cytokine that regulates a wide range of cellular and physiological functions, including immune and inflammatory responses. This cytokine has long been known as an anti-inflammatory cytokine that is critical to preventing the progression of an acute infection to a chronic condition. On the other hand, recent studies have unveiled the diverse roles of $TGF-{\beta}1$ on different stages of pneumococcal infections other than mitigating inflammation. This review summarizes the recent findings of the role of $TGF-{\beta}1$ on the pathophysiology of pneumococcal infections, which is fundamental to developing novel therapeutic strategies for such infections in immune-compromised patients.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.28-31
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• 1998

Nodule development was regulated partially by host plant factors originating in the shoots and roots. This study was performed to identify the origin of the factors regulating nodulation in supernodulating soybean (Glycine max [L.] Merr.) mutant 'SS2-2' which was isolated recently from ethyl methanesulfonate (EMS) mutagenesis of 'Sinpaldalkong 2'. Self- and reciprocal-grafts were made among three soybean genotypes which consisted of two supernodulating mutants, SS2-2 and 'nts 382', and a normal nodulating Sinpaldalkong 2. Self-grafted supernodulating mutants were characterized by greater nodule number, nodule dry weight, and $C_2$H$_2$ reduction activity than self-grafted wild types. They were also characterized by relatively higher nodule to root dry weight. Significant shoot genotypic effects were observed on nodule number, nodule dry weight, and $C_2\;H_2$ reduction activity per plant, whereas varying root genotypes had no effects. From this result, it is surmised that supernodulating characters are controlled by a graft-transmissible shoot factor, and mutant SS2-2 may have similar nodulation mechanism to the former supernodulating nts 382. In all grafts, both supernodulating mutants and Sinpaldalkong 2 maintained the similar balance between above ground and below ground parts regardless of significant differences in partitioning of dry matter into root and nodule between supernodulating mutants and Sinpaldalkong 2.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.432-439
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• 2016

Shiga toxins (Stxs) produced by Shiga toxin-producing Escherichia coli (STEC) strains are major virulence factors that cause fatal systemic complications, such as hemolytic uremic syndrome and disruption of the central nervous system. Although numerous studies report proinflammatory responses to Stx type 1 (Stx1) or Stx type 2 (Stx2) both in vivo and in vitro, none have examined dynamic immune regulation involving cytokines and/or unknown inflammatory mediators during intoxication. Here, we showed that enzymatically active Stxs trigger the dissociation of lysyl-tRNA synthetase (KRS) from the multi-aminoacyl-tRNA synthetase complex in human macrophage-like differentiated THP-1 cells and its subsequent secretion. The secreted KRS acted to increase the production of proinflammatory cytokines and chemokines. Thus, KRS may be one of the key factors that mediate transduction of inflammatory signals in the STEC-infected host.

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1270-1281
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• 2018

Periodontal disease is triggered by the host immune response to pathogens in the microbial biofilm. Worsening of periodontal disease destroys the tooth-supporting tissues and alveolar bone. As oral inflammation can induce systemic diseases in humans, it is important to prevent periodontal disease. In this study, we demonstrated that Curcuma xanthorrhiza supercritical extract (CXS) and its active compound, xanthorrhizol (XAN), exhibit anti-inflammatory effects on lipopolysaccharide (LPS)-treated human gingival fibroblast-1 cells and anti-osteoclastic effects on receptor activator of nuclear factor kappa B ligand (RANKL)-treated RAW264.7 cells. LPS-upregulated inflammatory factors, such as nuclear factor kappa B p65 and $interleukin-1{\beta}$, were prominently reduced by CXS and XAN. In addition, RANKL-induced osteoclastic factors, such as nuclear factor of activated T-cells c1, tartrate-resistant acid phosphatase, and cathepsin K, were decreased in the presence of CXS and XAN. CXS and XAN inhibited the mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1) signaling pathway. Collectively, these results provide evidence that CXS and XAN suppress LPS-induced inflammation and RANKL-induced osteoclastogenesis by suppressing the MAPK/AP-1 pathway.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.3
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• pp.311-318
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• 1997

Ludwig's angina has been defined as a potentially lethal, rapidly spreading cellulitis, involving the sublingual and submandibular spaces, and is manifesed by a brawny, suprahyoid induration, tender swelling in the floor of mouth, elevation and posterior displacement of tongue. This paper is of interest not only because of severity of infection but also because of associated diabetic mellitus. Diabetes mellitus is a complex syndrome of disordered metabolism and elevated blood glucose, it results from deficiency of insulin secretion of combination of insulin resistance and inadequate insulin secretion. The effects of diabetic mellitus include neuropathy, vascular insufficiency, decreased leukocytic function, hematologic change etc. Clinically this may be refelected by the increased severity of infections seen in diabetics. The treatment of infections in diabetics are reduction of number of microbes through the use of appropriated antimicrobial agents and proper surgical drainage and improvement of the host factors by tight control of insulin replacement and immediate intervention to correct abnormalities of the local factors by drainage, debriment, and removal of avoidance of foreign bodies. The authors present the report of the Ludwig's angina in patient with diabetic mellitus, with literature review and good clinical result.

• Molecules and Cells
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• v.27 no.2
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• pp.237-241
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• 2009

Pathogens Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm) contain a large number (> 12,000) of Simple Sequence Repeats (SSRs). To study the extent to which these features have contributed to the diversification of genes, we have conducted comparative studies with nineteen genomes of these bacteria. We found 210 genes with characteristic types of SSR variations. SSRs with nonamer repeat units were the most abundant, followed by hexamers and trimers. Amino acids with smaller and nonpolar R-groups are preferred to be encoded by the variant SSRs, perhaps due to their minimal impacts to protein functionality. A majority of these genes appears to code for surface or secreted proteins that may directly interact with the host factors during pathogenesis or other environmental factors. There also are others that encode diverse functions in the cytoplasm, and this protein variability may reflect an extensive involvement of phase variation in survival and adaptation of these pathogens.

• The Plant Pathology Journal
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• v.17 no.1
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• pp.45-51
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• 2001

A root rot/vine decline disease occurred naturally on bottle gourd-stocked watermelon, melon, oriental melon and squash grown in greenhouses, but not on these plants grown in fields. Self-rooted watermelon, cucumber, pumpkin and luffa were also proven to be hosts of the pathogen by artificial inoculation in this experiment. The pathogen was identified as Monosporascus cannonballus by comparing microscopic characteristics of fungal structures with those of previously identified fungal strains. Our field investigations showed that the temperature and electric conductivity of soil in infected greenhouses were higher and the soil moisture content was lower than in noninfected greenhouses. To investigate soil-environmental factors affecting disease development, greenhouse trials and inoculation experiments were conducted. The host plants inoculated and grown under conditions of high soil temperature and electrical conductivity ($35\pm2^{\circ}$, 3.2-3.5 mS) and with low soil moisture content (pF 3.0-4.5) were most severely damaged by the fungal disease. Since plants growing in greenhouses ae usually exposed to such environmental conditions, this may be the reason why the monosporascus root rot/vine decline disease has occurred only on cucurbits cultivated in greenhouses but not in field conditions.