• The Pure and Applied Mathematics
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• v.2 no.2
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• pp.149-156
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• 1995

In stability theory of polysystems two concepts that playa very important role are the limit set and the prolongational limit set. For the above two concepts, A.Bacciotti and N.Kalouptsidis studied their properties in a locally compact metric space [2]. In this paper we investigate their results in c-first countable space which is more a general space than a metric space.(omitted)

• Journal of Microbiology
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• v.45 no.4
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• pp.281-285
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• 2007

Cold environments, including polar and alpine regions, are colonized by a wide diversity of micro-organisms able to thrive at low temperatures. There is evidence of a wide range of metabolic activities in alpine cold ecosystems. Like polar microorganisms, alpine microorganisms playa key ecological role in their natural habitats for nutrient cycling, litter degradation, and many other processes. A number of studies have demonstrated the capacity of alpine microorganisms to degrade efficiently a wide range of hydrocarbons, including phenol, phenol-related compounds and petroleum hydrocarbons, and the feasibility of low-temperature bioremediation of European alpine soils by stimulating the degradation capacity of indigenous microorganisms has also been shown.

• Journal of Microbiology
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• v.43 no.4
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• pp.366-369
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• 2005

Avian influenza viruses playa crucial role i,n the creation of human pandemic viruses. In this study, we have demonstrated that both human and avian influenza receptors exist in cells in the respiratory and intestinal tracts of chickens. We have also determined that primarily cultured chicken lung cells can support the replication of both avian and human influenza viruses.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.162.1-162.1
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• 2003

The purpose of this study was to determine the possibility of sphingolipid as a diagnostic marker for Myocardiac Infarction(MI), atherosclerosis-related cardiovascular disease. Sphingolipids are known to playa role in the occurrence of atherosclerosis in human blood vessels. Platelet-poor plasma(PPP) and washed platelets were prepared from healthy volunteers and MI patients, and sphingolipids analyzed. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.310.2-310.2
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• 2002

Macrophage activated by LPS/IFN-${\gamma}$ playa important role in imflammation. innate immunity and tumor immunity. The recent report has indicated that LPS treated bone marrow macrophages were induced apoptosis. but IFN-${\gamma}$ protects from apoptosis induced by several stimuli in complete medium condition (Jordi et al.. Immunity. Vo1.11. 103-113. 1999). (omitted)

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.2
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• pp.63-67
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• 2006

Suppressor of cytokine signaling (SOCS) is known to playa key role as a negative feedback regulator in JAK/STAT signaling cascade in innate immunity. Our laboratory has recently been interested in elucidating the interactions between Spodoptera exigua (Se) and SeNPV. This context leads us to clone and characterize SeSOCS that may have important functions in response to SeNPV infection. Using the RT-PCR and TA cloning approach, we found a partial fragment (416 bp) of SeSOCS. Blast search and multiple alignment data showed that it has a homology to various insects such as Anopheles gambiae (78%), Aedes aegypti (75%), Drosophila melanogastar (77%), Mus musculus (69%), and Homo sapiens (69%). Temporal induction patterns of SeSOCS were analysed after being immune-challenged with either NPV or laminarin. It showed that the level of SeSOCS mRNA was strongly induced in a biphasic manner in response to SeNPV and laminarin, respectively. It seems that SOCS, a negative regulator of JAK/STAT signaling system is also present in S. exigua and may playa role in innate immunity albeit its precise role should be further elucidated at the molecular and cellular level in the early phase of SeNPV infection in larvae.

• Reproductive and Developmental Biology
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• v.32 no.2
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• pp.97-104
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• 2008

Plasminogen activators (PAs) are serine protease that cleave plasminogen to form the active protease plasmin. PA/plasmin system playa role in mammalian fertilization and motility and acrosome reaction of sperm. The present study was undertaken to identify PAs in porcine gametes and investigate a possible role of plasminogen in in vitro fertilization in the pig. When boar spermatozoa were preincubated in a fertilization medium (mTBM) for 0, 2, 4 or 6 h, the activity of tPA-PAI ($110{\sim}117\;kDa$), tPA ($62{\sim}70\;kDa$), and uPA ($34{\sim}38\;kDa$) was observed in the sperm incubation medium and sperm sample. PA activities in the sperm incubation medium significantly (p<0.05) increased according to increasing incubation times, while PA activities in sperm significantly (p<0.05) decreased at the same times. In addition, the rate of acrosome reaction in spermatozoa increased by increasing culture times. When oocytes were separated from porcine cumulus-oocytes complexes at 0, 22 or 44 h of maturation culture, no PA activities were observed in cumulus free-oocyte just after aspiration from follicles. However, the activity of tPA-PAI ($108{\sim}113\;kDa$) and tPA ($75{\sim}83\;kDa$) was observed at 22 h of in vitro culture and significantly (p<0.05) increased as the duration of the culture increased. On the other hand, when porcine oocytes were activated by sperm penetration or calcium ionophore, plasminogen significantly (p<0.05) increased ZP dissolution time (sec) in activated oocytes by sperm penetration. These results suggest that supplementation of plasminogen to fertilization medium may playa positive role in the improvement of in vitro fertilization ability in the pig.

• Journal of Environmental Health Sciences
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• v.34 no.2
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• pp.117-123
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• 2008

Allergic diseases have been dramarically increased over recent years, especially in industrialized countries. Oxidative stress has been believed to playa significant role in the occurrence of the allergic inflammatory responses. Although previous studies concerning oxidative stress and systemic inflammation have been reported, few data is available, and other allergic diseases, except for asthma, are hardly studied about the association with oxidative stress. This study evaluated the relationship between allergic disease and Malondialdehyde (MDA) as an indicator of oxidative stress. The study population was 197 male adults living in an industrial area. The ISAAC questionnaire was used to confirm wheezing and rhinitis, and atopy was evaluated by skin prick test. MDA was analyzed by spectrophotometer. To examine bronchial hyperresponsiveness (BHR), methacholine test was performed, and the index of bronchial responsiveness (BR index) was calculated. We used multivariate logistic regression model and general linear model with SAS program. We found significant associations of MDA with brindex (p=0.023), rhinitis (p=0.016), atopy (p=0.03), adjusted by age, smoking, and body mass index (BMI). On the contrary, there was no significant difference of MDA with the status of asthma. Our result suggests that oxidative stress may playa major role in the occurrence of allergic response in male adults.

• The Journal of Korean Society of Virology
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• v.28 no.1
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• pp.1-9
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• 1998

To study the relation between ectoparasite, Rickettsia and hanntan virus in bats, four order of Athropoda were collected from Rhinolophus ferrumequinum captured in Cheju and Eptesicus serotinus captured in Chungnamin from July 1989 to March 1998. Also antibody of Rickettsia and hanntan virus were detected by immunofluoroscent antibody technique and RT-PCR. The results are as follows. 1. Five species of Acarina were identified from E. serotinus: Leptotrobidium subakamushi of Trombiculidae, Macronyssus coreanus, Steatonyssuss spinosuss and Steatonychus superans of Macronyssidae, Argas vespertilionis of Metastigmata. 2. Ischnopsyllus needhami of Siphonaptera and Cimex of Hemiptera were identified from E. serotinus. 3. Cycteribia uenoi and Brachytarsina kanoi of Diptera were identified from R. ferrumequinum. 4. The positive rate of rickettsial antibodies in E. serotinus were 17.58%, 15.15%, 22.22%, 52.73% against R. tsutsugamushi, R. typhi, R. sibirica and R. thai tick typhus, respectively. The high positive rate of antibody related to the high content of Arthropoda. 5. The Positive rate of hantaan virus IFA antibodies were 3.4% (27 of 802) and hanntan virus infection rate 36.7% (22 of 60) by RT-PCR in bats. According these result, we showed that certain species of Athropoda isolated playa role as vector of Rickettsia in E. serotinus. Also bats playa role as a reservoir of hantaan virus in nature.

• Anxiety and mood
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• v.1 no.1
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• pp.7-13
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• 2005

Anxiety is one of the basic emotions which human experiences across different cultures in the world and it can be observed in mammals. Our understanding of the neurobiology of this emotion has made some advances, even though it has not been completed, with the development and advance in the investigation method including neuroimaging, neurochemical, and genetic approaches. In this article, the neuroanatomical and neurochemical basis of anxiety is reviewed. The amygdaloid complex has been known to playa key role in processing of anxiety or fear. It has extensive afferent and/or efferent connections with cortical and subcortical structures. The mesial temporal structures including hippocampus appear to be involved in acquisition of anxiety and related behaviors. The prefrontal cortical structures appear to play important roles in conscious awareness of anxiety and in modulating anxiety and related behavior. The bed nucleus of the stria terminalis (BNST) is known to playa critical role in unconditioned fear response. The central noradrenergic system and hypothalamo-pituitary-adrenal axis are known to play important roles in modulating and expressing anxiety-related responses. Anxiety has been gathering attentions from many investigators and numerous preclinical and clinical investigations of anxiety and anxiety disorders have been done. In particular, neural plasticity in critical period and the psychobiological factors related to resilience to extreme stress and anxiety are important issues in this field.