• Research in Plant Disease
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• v.11 no.2
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• pp.98-105
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• 2005

All viruses have few genes relative to their hosts. Viruses, thus, utilize many host factors for efficient viral replication in host cell. Virus-host interactions are crucial determinations of host range, replication, and pathology. Host factors participate in most steps of positive-strand RNA virus infection, including entry, viral gene expression, virion assembly, and release. Recent data show that host factors play important roles in assembling the viral RNA replication complex, selecting and recruiting viral RNA replication templates, activating the viral complex for RNA synthesis, and the other steps. These virus-host interactions may contribute to the host specificity and/or pathology. Positive-strand RNA viruses encompass over two-thirds of all virus genera and include numerous pathogens. This review focuses on the importance of host factors involved in positive strand plant RNA virus genome replication.

• Journal of Korea Trade
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• v.23 no.2
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• pp.88-109
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• 2019

Purpose - This paper examines the effects of host country's non-economic factors on foreign affiliate's financial and operational performance. Design/Methodology - Using Korean-owned foreign affiliate-level data, we employ various measures that represent host country's non-economic factors and examine their effects on foreign affiliate's performance. We further investigate the effects of local top managers and local middle managers on the impact of country's non-economic factors on foreign affiliate's performance. Findings - We find that local top managers are effective in increasing foreign affiliate's financial performance by dealing with institutional and cultural factors, particularly in high-income countries, while local middle managers are effective in increasing affiliate's operational performance by responding to the changes in doing business factors, particularly in low-income countries. Originality/value - Considering that most of previous FDI studies focus on examining host country's economic factors on firm's FDI decision, our findings suggest that country's non-economic factors are strongly associated with actual business performance of foreign affiliates.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.173-183
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• 2015

The study conducted questionnaire analysis on 607 host company employee and 404 subcontractor employee in order to examine the difference in the safety culture cognition of host company and subcontractor. As a result, host company had higher recognition in all safety culture factors compare to that of subcontractor, and there were bigger gap of cognition in the 'cognition in safety status and culture', 'accident and near-miss', 'immediate superior's concentration degree in safety and health' than that of other cognition factors. Furthermore, team leaders showed the highest cognition in both host company and subcontractor, and employees with above 20 year career had the highest cognition in both host company and subcontractor. There is high relationship between host company and subcontractor in the correlations in safety culture cognition factors. Through this study, we identified the difference in the safety culture cognition factor of host company and subcontractor.

• Journal of Microbiology and Biotechnology
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• v.27 no.9
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• pp.1549-1558
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• 2017

Despite significant efforts to improve the treatment of tuberculosis (TB), it remains a prevalent infectious disease worldwide owing to the limitations of current TB therapeutic regimens. Recent work on novel TB treatment strategies has suggested that directly targeting host factors may be beneficial for TB treatment. Such strategies, termed host-directed therapeutics (HDTs), focus on host-pathogen interactions. HDTs may be more effective than the currently approved TB drugs, which are limited by the long durations of treatment needed and the emergence of drug-resistant strains. Targets of HDTs include host factors such as cytokines, immune checkpoints, immune cell functions, and essential enzyme activities. This review article discusses examples of potentially promising HDTs and introduces novel approaches for their development.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3879-3884
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• 2014

Background: In chronic hepatitis B (CHB), the presence of hepatic steatosis (HS) seems to be associated with known host and viral factors which may influence the long-term prognosis of chronic hepatitis B (CHB), probably leading to cirrhosis and hepatocellular carcinoma (HCC). Different from chronic hepatitis C (CHC), factors associated with HS in CHB are not clearly explored. Materials and Methods: 160 CHB patients were divided into two groups depending on the results of liver biopsy. Group I consisted of 71 patients with confirmed steatosis. Group II comprised 89 patients without steatosis. The groups were compared in terms of basal characteristics, body mass index (BMI), liver enzymes (ALT, AST, ALP), serum fasting blood sugar (FBS) and lipids, hepatitis B e antigen (HBeAg), viral load, and histological findings. Results: In terms of host factors, male gender, older age, BMI, high serum FBS and lipid levels were associated with HS. On the other hand, ALT levels, the HAI scores of necroinflammation and stage of fibrosis did not associate with HS. On multivariate analysis, parameters of sex, BMI, cholesterol and FBS levels were independently associated with HS. Regarding viral factors, HBeAg negativity was significantly associated with HS (81.7%, p value 0.006), but not HBV DNA level (p value 0.520). Conclusions: HS in CHB appears to be unrelated to the status of HBV replication. However, fibrosis progression in CHB is related to variable host factors. HS may be enhanced through these factors in HBV chronic patients.

• Journal of Microbiology
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• v.41 no.2
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• pp.137-143
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• 2003

The present study was performed to identify pathogenic factors of Chlamydia trachomatis, which invade the host cell membrane. We prepared monoclonal antibody against C. trachomatis and searched for pathogenic factors using this antibody, and subsequently identified the surface components of the elementary body of C. trachomatis, i.e., major outer membrane protein (MOMP), lipopolysaccharide (LPS), and two other surface exposure proteins. These proteins are believed to be important in the pathogenesis of host cell chlamydial infection. Additionally, to identify factors related to the host cell and C. trachomatis, we prepared C. trachomatis infected and non-infected McCoy cell extracts, and reacted these with anti-chlamydial LPS monoclonal antibody. We found that anti-chlamydial LPS monoclonal antibody reacted with a 116 kDa proteinaceous McCoy cell membrane component.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.233-240
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• 1991

A female Brachymeria lasus (Walker) was exposed to one or four pupae of host Hyphantria cunea Drury for 20 minutes within a petri dish $(1.5\times9cm)$ to learn factors influencing the host discrimination by the parasitoid. It rejected the parasitized host with its rejection ratio 73.3% for the one pupal exposure vs 100% for the four pupal exposure scheme. The parasitoid could discriminate the parasitized host by its antennal drumming and ovipositor probing due to a pheromone-like external marking which is effective only for a certain peiod of time, and a host quality associated with the parasitoid development, respectively.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.151-152
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• 2002

Bacterial infection is a very complex process in which both pathogenic microorganisms and host cells play crucial roles, and it is the outcome of interactions between the two participants. To elucidate the bacterial pathogenesis mechanisms, therefore, it is essential to understand the cellular and systemic responses of the host as well as the virulence factors of the pathogen. Infection of a host by pathogenic bacteria causes drastic changes in the physiology of host cells, leading to activation of a program of various gene expression. (omitted)

• Proceedings of the Microbiological Society of Korea Conference
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• 2004.05a
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• pp.132-136
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• 2004

Understanding the molecular pathogenesis of the multifaceted host-pathogen interaction is critical in the development of improved treatment and prevention, as well as elucidating how certain bacteria can circumvent host defenses, multiply in the host, and cause such extensive damage. Disease caused by infection with V. vulnificus is remarkable for the invasive nature of the infection, ensuing severe tissue damage, and rapidly fulminating course. The characterization of somatic as well as secreted products of V. vulnificus has yielded a large list of putative virulence attributes, whose known functions are easily imagined to explain the pathology of disease. These putative virulence factors include a carbohydrate capsule, lipopolysaccharide, a cytolysin/hemolysin, elastolytic metalloprotease, iron sequestering systems, lipase, and pili. However, only few among the putative virulence factors has been confirmed to be essential for virulence by the use of molecular Koch's postulates. This presentation describes molecular biological characterization of the virulence factors contributing to survival as well as to toxigenesis of V. vulnificus.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.24
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• pp.107-125
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• 2004

This study is based on the survey data of 74 Korean multinational corporations, which undertook foreign direct investments from 1980 to 1996. The study examined the firm-specific as well as the host country-specific factors affecting the decision between shared and full ownership. According to the results of this study, as for the firm-specific factors, Korean firms entering foreign markets in order to penetrate local markets prefer shared ownership while those pursuing core business diversification prefer full ownership. As for the host country factors, the more advanced the host country(such as OECD countries) is, the more preference is given to full ownership.