• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.836-843
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• 2004

Nontypeable H. influenzae (NTHi), a Gram-negative obligate human pathogen, causes pneumonia, chronic bronchitis, and otitis media, and the respiratory epithelium is the first line of defense that copes with the pathogen. In an effort to identify transcriptional responses of human respiratory epithelial cells to infection with NTHi, we examined its differential gene expression using high density cDNA microarrays. BEAS-2B human bronchial epithelial cells were exposed to NTHi for 3 hand 24 h, and the alteration of mRNA expression was analyzed using microarrays consisting of 8,170 human cDNA clones. The results indicated that approximately 2.6% of the genes present on the microarrays increased in expression over 2-fold and 3.8% of the genes decreased during the 24-h infection period. Upregulated genes included cytokines (granulocyte-macrophage colony stimulating factor 2, granulocyte chemotactic protein 2, IL-6, IL-10, IL-8), transcription factors (Kruppel-like factor 7, CCAAT/enhancer binding protein $\beta$, E2F-1, NF-$\kappa$B, cell surface molecules (CD74, ICAM-1, ICAM-2, HLA class I), as well as those involved in signal transduction and cellular transport. Selected genes were further confirmed by reverse-transcription-PCR. These data expand our knowledge of host cellular responses during NTHi infection and should provide a molecular basis for the study of host-NTHi interaction.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.69-76
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• 1999

Acidovorax avenae subsp. avenae is the causal pathogen of several hosts including oats corn foxtail millet wheatgrass sugarcane and rice. The pathogen is a seedborne pathogen of rice and known to occur widely in rice growing countries. The pathogen cause inhibition of germination brown stripe on the leaf curling of the leaf sheath and abnormal elongation of the mesocotyl of irce. Bacterial colonies grow slowly and are convex circular and creamy with tan to brown center. The causal baterium is Gram-negative and rod shape with a single polar flagellum Nonfluorescence poly-$\beta$-hydroxybutyrate accumulation and precipitate formation around the colony on the medium are useful in the differentiation of this bacterium from other subspecies of A. avenae as well as nonfluorescent bacteria pathogenic to rice. This bacterium has belonged to the genus of Psdeudomonas but recently was transferred to the new genus Acidovorax on the basis of bacteriological and molecular biological data. However the difference of biochemical characteristics protein profile of the cell and host range among strains should be more clarified. To develop an effective control strategy for this disease understanding of detailed life cycle of the disease ritical environmental factors affecting disease development on each host and relationship to grain discoloration of rice are prerequisite. Although the affected area has been world-widely reported there is on recent progress on the understanding of the bacteriological and ecological characteristics of the causal bacterium and control means of the disease.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.6 no.1
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• pp.108-115
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• 2006

The inherent biology of neural stem cells (NSCs) endows them with capabilities that not only circumvent many of the limitations of other gene transfer vehicles, but that enable a variety of novel therapeutic strategies heretofore regarded as beyond the purview of neural transplantation, Most neurodegenerative diseases are characterized not by discrete, focal abnormalities but rather by extensive, multifocal, or even global neuropathology. Such widely disseminated lesions have not conventionally been regarded as amenable to neural transplantation. However, the ability of NSCs to engraft diffusely and become integral members of structures throughout the host CNS while also expressing therapeutic molecules may permit these cells to address that challenge. Intriguingly, while NSCs can be readily engineered to express specified foreign genes, other intrinsic factors appear to emanate spontaneously from NSCs and, in the context of reciprocal donor-host signaling, seem to be capable of neuroprotective and/or neuroregenerative functions. Stem cells additionally have the appealing ability to "home in" on pathology, even over great distances. Such observations help to advance the idea that NSCs - as a prototype for stem cells from other solid organs - might aid in reconstructing the molecular and cellular milieu of maid eve loped or damaged organs.

• Mycobiology
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• v.37 no.3
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• pp.161-170
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• 2009

Cryptococcus neoformans is a basidiomycete human fungal pathogen that causes meningoencephalitis in both immunocompromised and immunocompetent individuals. The ability to sense and respond to diverse extracellular signals is essential for the pathogen to infect and cause disease in the host. Four major stress-activated signaling (SAS) pathways have been characterized in C. neoformans, including the HOG (high osmolarity glycerol response), PKC/Mpk1 MAPK (mitogen-activated protein kinase), calcium-dependent calcineurin, and RAS signaling pathways. The HOG pathway in C. neoformans not only controls responses to diverse environmental stresses, including osmotic shock, UV irradiation, oxidative stress, heavy metal stress, antifungal drugs, toxic metabolites, and high temperature, but also regulates ergosterol biosynthesis. The PKC(protein kinase C)/Mpk1 pathway in C. neoformans is involved in a variety of stress responses, including osmotic, oxidative, and nitrosative stresses and breaches of cell wall integrity. The $Ca^{2+}$/calmodulin- and Ras-signaling pathways also play critical roles in adaptation to certain environmental stresses, such as high temperature and sexual differentiation. Perturbation of the SAS pathways not only impairs the ability of C. neoformans to resist a variety of environmental stresses during host infection, but also affects production of virulence factors, such as capsule and melanin. A drug(s) capable of targeting signaling components of the SAS pathway will be effective for treatment of cryptococcosis.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.3
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• pp.279-285
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• 2001

Although only a minority of the infected individuals develops atrophic gastritis and the malignancy, factors governing clinical outcomes subsequent to Helicobacter pylori (H. pylori) infection have not yet been defined. H. pylori infection is characterized by extensive infiltration of neutrophils. Myeloperoxidase (MPO) in neutrophils amplifies the oxidative potential of hydrogen peroxides that induce gastric mucosal damage, thus MPO is suspected to play a role in H. pylori-induced gastric injury. Therefore, we explored the association of host MPO genetic polymorphism with atrophic gastritis upon H. pylori infection. Biopsy specimens taken from the gastric mucosa were examined histologically in 87 patients. The PCR-RFLP assay was used to characterize MPO genotypes. The distributions of MPO genotypes were MPO (G/G) 82% and MPO (G/A) 18%. None of MPO (A/A) genotype was observed. A strong positive correlation between the levels of neutrophil infiltration and gastric atrophy found only in MPO (G/G) but not in MPO (G/A) genotype. These results suggest that MPO genotype is a critical determinant in the pathogenesis of atrophic gastritis subsequent to H. pylori infection. Further works need to clarify the functional relevance of MPO genetic polymorphisms on gastric cell injury.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1914-1915
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• 2007

The period and strength of the pulse on the radial artery are important physiological factors, and they have been used to diagnosis in both Western and Eastern countries for a long time and has been developed as a unique method of diagnosis at each countries. Recently, there are a lot of systems which can give diagnosis information by recording the pulse wave and analyzing the characteristics of the pulse shape. This study describes the Pulse-Wave Measurement System which is able to measure the pulse wave signal using piezoresistive sensor and the pulse wave signal measured by the developed system is transmitted to a computer on the basis of the USB Driver. It has finally shown the the pulse wave signal measured by the sender is appeared to the host PC in real time. The Pulse-Wave Measurement System used the piezoresistive sensor to measure the pulse wave signal and the differential amplifier(AD620) to amplify the pulse wave signal which is small signal. And it used the ADC to convert analog to digital for the measured analog signal and the interface with a computer. It transmitted the measured pulse signal through USB transmission module to the host computer and Labview tool shows it. This Pulse-Wave measurement system will afford comvenience of detecting pulse wave to user related to oriental medicine.

• Parasites, Hosts and Diseases
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• v.59 no.1
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• pp.1-8
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• 2021

Leptotrombidium scutellare is one of the 6 main vectors of scrub typhus in China. It has been found in more than 15 provinces of China. Especially in Yunnan, it was found to be mainly distributed in some mountainous areas with high altitude, low temperature and low precipitation. Rodents and some other small mammals were the most common hosts of L. scutellare. To date, more than 40 host species of L. scutellare have been recorded with very low host specificity, and the main hosts varied in different geographical regions. L. scutellare had a strong resistance against the cold environment, and the temperature and humidity were 2 important factors affecting its growth and development. Among different individuals of their rodent hosts, L. scutellare mites often showed an aggregated distribution pattern, which reflected the interspecific cooperation of the mites. The chromosome karyotype of L. scutellare was 2n=16 and all the 8 pairs of chromosomes were short rod-shaped with metacentric or sub-metacentric types. The isozyme spectrum supported that L. scutellare, L. deliense and L. rubellum were in the same species group. Based on the natural infection, experimental transmission and epidemiological evidence, L. scutellare has been eventually confirmed as the second major vector of scrub typhus in China, which is second only to L. deliense.

• Journal of Korea Trade
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• v.23 no.8
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• pp.73-88
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• 2019

Purpose - This paper finds the repurchase intentions of customers in a sharing economy via Airbnb and Uber, which are classic sharing-economy service businesses. Design/methodology - This paper analyzes sharing economy effects using variables in a structural equation model. Findings - We verified that values have a significant effect on the trust in a platform. We also verified that the effects that value propositions have on repurchase intention are significant. Research Limitations/Implications - First, there may be some distinction between men and women with regard to divided trust. Second, if commitment is divided into commitment to the host and commitment to the platform, as is the case for trust, the results will not be as expected. Third, if results could be categorized by nationality after gathering more samples, each nationality might have different opinions about these factors. Finally, the sharing economy can be identified and analyzed for various industries, such as space, transportation, and service. At this point, it is inconvenient to not have more implications. Originality/value - This study focuses on the repurchase intentions of customers. Unlike earlier studies, it is meaningful that trust is divided between the host and the platform, and that it can be analyzed. It is also important to establish the relationship between trust and commitment, and the relationship toward repurchasing in the shared-economy.

• Korean Journal of Plant Tissue Culture
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• v.27 no.4
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• pp.245-258
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• 2000

Somatic embryogenesis has become a major tool in the study of plant embryology, as it is possible in culture to manipulate cells of many plant species to produce somatic embryos in a process that is remarkably similar to zygotic embryogenesis. Traditionally, the process has been studied by an examination of the ex vitro factors which influence embryo formation. Later structural, physiological and biochemical approaches have been applied. Host recently, molecular tools are being used. Together, these various approaches are giving valuable information on the process. This article gives an overview of somatic embryogenesis by reviewing information on the morphogenesis, physiology, biochemistry and molecular biology of the process. Topics covered include a brief description of the factors involved in the production of embryogenic cells. Carrot cell suspension is most commonly used, and the development of a high frequency and synchronous system is outlined. At the physiological and biochemical lev-els various topics, including the reactivation of the cell cycle, changes in endogenous growth regulators, amino acid, polyamine, DNA, RNA and protein metabolism, and embryogenic factors in conditioned medium are all discussed. Lastly, recent information on genes and molecular markers of the embryogenic process are outlined. Somatic embryogenesis, the best example of totipotency in plant cells, is not only an important tool in studies in basic biology, but is potentially of equal significance in the micropropagation of economically important plants.

• Safety and Health at Work
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• v.2 no.2
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• pp.183-193
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• 2011

Objectives: A rapid increase in the population of migrant workers in Korea has brought new challenges regarding the possible effects of acculturation on health. The purpose of this study was to examine the influence of acculturation- and work-related psychosocial factors on work-related musculoskeletal disorders among migrant female workers living in Korea. Methods: A cross-sectional survey design was used. A translated, structured questionnaire was administrated to 156 southeastern Asian female full-time workers living in Korea. Results: About 35% of the participants experienced some type(s) of work-related musculoskeletal disorder(s), which were more prevalent in Vietnamese women than in Thai and Filipino women. Women who preferred to maintain their own heritage and to reject the host country heritage were at risk for work-related musculoskeletal disorders. Conclusion: Acculturation strategy and nationality were found to be significant factors associated with work-related musculoskeletal disorders. Health professionals need to accommodate acculturation contexts into risk assessment and intervention development for work-related musculoskeletal disorders separately for different nationalities.