• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.367-371
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• 2001

The chromosome 7-linked long QT syndrome (LQT2) is caused by mutations in the human ether-a- go-go-related gene (HERG) that encodes the rapidly activating delayed rectifier $K^+$ current, $I_{Kr},$ in cardiac myocytes. Different types of mutations have been identified in various locations of HERG channel. One of the mechanisms for the loss of normal channel function is due to membrane trafficking of channel protein. The decreased channel function in some deletion mutants appears to be due to loss of coupling with wild type HERG to form the functional channel as the tetramer. Most of missense mutants with few exceptions could interact with wild type HERG to form functional tetramer and caused dominant negative suppression with co-injection with wild type HERG showing variable effects on current amplitude, voltage dependence, and kinetics of activation and inactivation. Two missense mutants at pore regions of HERG found in Japanese LQT2 (A614V and V630L) showed accentuated inward rectification due to a negative shift in steady-state inactivation and fast inactivation. One mutation in S4 region (R534C) produced a negative shift in current activation, indicating the S4 serving as the voltage sensor and accelerated deactivation. The C-terminus mutation, S818L, could not express the current by mutant alone and did not show dominant negative suppression with co-injection of equal amount of wild type cRNA. Co-injection of excess amount of mutant with wild type produced dominant negative suppression with a shift in voltage dependent activation. Therefore, multiple mechanisms are involved in different mutations and functional abnormality in LQT2. Further characterization with the interactions between various mutants in HERG and the regulatory subunits of the channels (MiRP1 and minK) is to be clarified.

• Korean Journal of Veterinary Research
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• v.53 no.1
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• pp.29-35
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• 2013

To develop a live vaccine candidate using an attenuated strain of Salmonella Typhimurium (ST), biochemical properties, plasmid profile, PFGE patterns and pathogenic analysis of the ST isolate were carried out after sequential passage of the ST isolate in porcine neutrophils. By the passage, the ability of the neutrophil-adapted isolate to utilize d-xylose was lost, while the ability of the strain to ferment trehalose was delayed after 2 or more days of the culture. Also, changes including deletion of the gene fragments were observed in PFGE analysis of the neutrophil-adapted isolates. Two plasmids, 105kb and 50kb, were cured in the strain passaged over 15 times in porcine neutrophils. The 50% of lethal dose ($LD_{50}$) of the parent strain was changed from $1{\times}10^5\;LD_{50}$ to $6{\times}10^6\;LD_{50}$ by the passage in intraperitoneal injection of the strains into mice. These results suggested that bacterial genotypic and phenotypic responses might be globally altered depending on the inside environment of neutrophils.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.50-50
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• 2003

We have identified and analysed a putative response regulator two-component gene (CaSKN7) from Candida albicans and its encoding protein (CaSkn7). CaSKN7 has an open reading frame of 1677bp. CaSKN7 encodes a 559 amino acid protein (CaSkn7) with an estimated molecular mass of 61.1 kDa. CaSKN7 is a homologue of a Saccharomyces cerevisiae SKN7 that is the regulator involved in the oxidative stress response. To study the role of CaSKN7, we constructed a CAI4-derived mutant strain carrying a homozygous deletion of the CaSKN7 gene. In the caskn7 disruptant cells, the formation of germ tube require shorter time than that in the congenic wild-type strain but the growth of mycelium delayed in liquid media. In contrast, the caskn7 disruptant cells attenuate the differentiation in solid media and the virulence in mouse model system. Expression level of hypha-specific and virulence genes - HYR1, ECE1, HWP1, and ALS1 - in the caskn7 disruptant cells increased as compared with that in the congenic wild-type strain in 10％ serum YPD. Skn7 in 5. cerevisiae was found to bind the HSE element from the SSA promoter, Also, CaSkn7 contains heat shock factor DNA-binding domain and the promoters of these genes have HSE-like sties. Therefore these results show that CaSKN7 regulate the differentiation and virulence of C. albicans.

• The Plant Pathology Journal
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• v.34 no.6
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• pp.470-479
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• 2018

The rice blast pathogen Magnaporthe oryzae is a global threat to rice production. Here we characterized RHO2 gene (MGG_02457) that belongs to the Rho GTPase family, using a deletion mutant. This mutant ${\Delta}Morho2$ exhibited no defects in conidiation and germination but developed only 6% of appressoria in response to a hydrophobic surface when compared to the wild-type progenitor. This result indicates that MoRHO2 plays a role in appressorium development. Furthermore, exogenous cAMP treatment on the mutant led to appressoria that exhibited abnormal morphology on both hydrophobic and hydrophilic surfaces. These outcomes suggested the involvement of MoRHO2 in cAMP-mediated appressorium development. ${\Delta}Morho2$ mutation also delayed the development of appressorium-like structures (ALS) at hyphal tips on hydrophobic surface, which were also abnormally shaped. These results suggested that MoRHO2 is involved in morphological development of appressoria and ALS from conidia and hyphae, respectively. As expected, ${\Delta}Morho2$ mutant was defective in plant penetration, but was still able to cause lesions, albeit at a reduced rate on wounded plants. These results implied that MoRHO2 plays a role in M. oryzae virulence as well.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.13 no.2
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• pp.80-85
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• 2017

Angelman syndrome is a rare disorder caused by deletion or inactivation of genes on the maternally inherited chromosome 15. This neurodevelopmental disorder is characterized by developmental and intellectual delay, speech impairment, sleep disturbance, seizures, motor dysfunction, and frequent laughing or smiling. Orofacial characteristics include a prominent mandible, large mouth, prominent cheeks, a tendency to rest the tongue between the dental arches, excessive drooling, and excessive chewing behavior. Patients with this syndrome usually require general anesthesia even in a simple operation, because of risk of perioperative seizure during dental procedure. This is a case report about dental treatment of a 3-year-old female patient with Angelman syndrome under general anesthesia. This case suggests that the dental treatment under general anesthesia can be considered a safe component for the uncooperative, delayed developmental patients with underlying disease. Also, periodic dental exam appointment should be made to provide the patients with preventive treatments and to make them remain familiar with the dental environment.

• The Korean Journal of Mycology
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• v.41 no.1
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• pp.1-8
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• 2013

COP9 signalosome (CSN), which is originally identified as the regulator of the photomorphogenic development in plant, is highly conserved protein complex in diverse eukaryotic organisms. Most eukaryotic CSN complex is composed of 8 subunits, which is structurally and functionally similar to the lid subunit of 26S proteasome and eIF3 translation initiation complex. CSN play important functions in the regulation of cell cycle and checkpoint response by controlling Cullin-Ring E3 ubiquitin ligases (CRL) activities. CSN exhibits an isopeptidase activity which cleaves the neddylated moiety of cullin components. In fission yeast, S-phase cell cycle progression was delayed and the sensitivity to g-ray or UV was increased in CSN1 and CSN2 deletion mutants, indicating that yeast CSN is also involved in the checkpoint regulation. CSN in fungal system more closely resembles that of the higher organisms in the structure and assembly of their components. Functionally, CSN is associated with the regulation of conidiation rhythms in Neurospora crassa and the sexual development in Aspsergillus nidulans. Recent studies also revealed that CSN functions as an essential cell cycle regulator, playing key roles in the regulation of DNA replication and DNA damage response in Aspergillus. Overall, CSN of microorganisms, such as fission yeast and fungi, share functionally common aspects with higher organisms, implying that they can be useful tools to study the role of CSN in the CRL-mediated diverse cellular activities.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.3
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• pp.313-319
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• 2016

Wolf-Hirschhorn syndrome (WHS), associated with the deletion of the short arm of chromosome 4, causes multiple congenital malformations. Patients suffer from various deformities, including mental and growth disorders, epilepsy, hypotonia, congenital heart defects, and atypical craniofacial features. The "Greek warrior helmet appearance" is the most characteristic feature, with a prominent glabella, high arched eyebrow, broad nasal bridge, and hypertelorism. Cleft lip with or without cleft palate is observed in 30% of patients. Dental structure anomalies also exist including multiple tooth agenesis and over-retained primary molars caused by MSX1 gene impairment, and cone-shaped and taurodontic teeth. This case, a 9-year-old girl with WHS, showed intellectual disability, delayed growth development, previous occurrence of seizures, otitis media, and the typical facial features of WHS. Dental findings included multiple congenital missing teeth, over-retained primary teeth, and severe caries on the primary molars. Dental treatments were performed under general anesthesia. This report documents the characteristics of WHS, including general and oral features, and discusses the importance of oral hygiene and preventive dental management.

• Journal of The Korean Dental Society of Anesthesiology
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• v.13 no.1
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• pp.13-18
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• 2013

CATCH 22 syndrome is a one of the most common chromosome microdeletion syndrome with multiple organ anomalies in humans, with an incidence of approximately 1:4,000 to 1:5,000 live births. It is caused by a microdeletion of 1.5 to 3.0 megabases on the long arm of chromosome 22. The phenotypic spectrum of this disorder is wide and various. A 19-year-old patient who showed delayed growth and development (Height; 110 cm, Weight; 18 kg) was referred to our department for the treatment of dental cavities. She was diagnosed as CATCH 22 syndrome in 2004. Physical examination revealed hypertelorism, a short philtrum, thick reflected lips and a small mouth. She underwent cleft palate surgery at 1 year of age and heart valve surgery due to the cardiovascular abnormality at 13 years of age. Convulsive seizures had persisted until 5 years ago but are well controlled at present. Oral examination showed poor oral hygiene, crowding, prolonged retention on #65, 75 and dental cavities on #16, 21, 65, 26, 36, and 46. Cavity treatment and prophylaxis were performed under general anesthesia. Also continuous follow-up checks have been carrying out with the periodic prophylaxis and dental home education. Problems with numerous cavities and gingivitis which can lead to specific risks are common for CATCH 22 syndrome patients. It is therefore of great importance that these patients are referred to foremost physician and dental specialist for the oral care. In addition, preventive treatment targeting the risk of dental cavities and gingivitis is especially important and, as the syndrome involves many different medical problems, the dental treatment should be carried out in collaboration with the patient's physician.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.50-55
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• 2019

Recently Ransomware attacks are continuously increasing, and new Ransomware, which is difficult to detect just with a basic vaccine, continuously has its upward trend. Various solutions for Ransomware have been developed and applied. However, due to the disadvantages and limitations of existing solutions, damage caused by Ransomware has not been reduced. Ransomware is attacking various platforms no matter what platform it is, such as Windows, Linux, servers, IoT devices, and block chains. However, most existing solutions for Ransomware are difficult to apply to various platforms, and there is a limit that they are dependent on only some specific platforms while operating. This study analyzes the problems of existing Ransomware detection solutions and proposes the onboard module based Ransomware detection system; after the system defines the function of necessary elements through analyzing requirements that can actually reduce the damage caused by the Ransomware from the viewpoint of users, it supports various OS without pre-installation and is able to restore data even after being infected. We checked the feasibility of each function of the proposed system through the analysis of the existing technology and verified the suitability of the proposed techniques to meet the user's requirements through the questionnaire survey of a total of 264 users of personal and corporate PC users. As a result of statistical analysis of the questionnaire results, it was found that the score of intent to introduce the system was at 6.3 or more which appeared to be good, and the score of intent to change from existing solution to the proposed system was at 6.0 which appeared to be very high.

• The Plant Pathology Journal
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• v.39 no.4
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• pp.361-373
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• 2023

In plant-pathogen interactions, Magnaporthe oryzae causes blast disease on more than 50 species of 14 monocot plants, including important crops such as rice, millet, and most 15 recently wheat. M. oryzae is a model fungus for studying plant-microbe interaction, and the main source for fungal pathogenesis in the field. Here we report that MoJMJD6 is required for conidium germination and appressorium formation in M. oryzae. We obtained MoJMJD6 mutants (ΔMojmjd6) using a target gene replacement strategy. The MoJMD6 deletion mutants were delayed for conidium germination, glycogen, and lipid droplets utilization and consequently had decreased virulence. In the ΔMojmjd6 null mutants, global histone methyltransferase modifications (H3K4me3, H3K9me3, H3K27me3, and H3K36me2/3) of the genome were unaffected. Taken together, our results indicated that MoJMJD6 function as a nuclear protein which plays an important role in conidium germination and appressorium formation in the M. oryzae. Our work provides insights into MoJMJD6-mediated regulation in the early stage of pathogenesis in plant fungi.