• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.12
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• pp.59-67
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• 1998

In this paper, a rigorous three-dimensional Monte Carlo approach to simulate the sputter yield as a function of the incident ion energy and the incident angle as well as the atomic ejection distribution of the target is presented. The sputter yield of the target atom (Cu, Al) has been calculated for the different species of the incident atoms with the incident energy range of 10 eV ~ 100 KeV, which coincides with the previously reported experimental results. According to the simulation results, the calculated sputter yield tends to increase with the amount of the energy of the incident atoms. Our simulation revealed that the maximum sputter yield can be obtained for the incident atom with 10 KeV for the heavy ion, while the maximum sputter yield for the light ion is for the incident atoms with an energy less than 1 KeV. The sputter yield increases with angle of incidence and seems to have the maximum value at 68$^{\circ}$. For angular distributions of the sputtered particle, the atoms in the direction normal to the surface increase with angle of incidence. Furthermore, we has conducted the parallel computation on CRAY T3E supercomputer and built a GUI(Graphic User Interface) system running the sputter simulator.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.997-1005
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• 1996

For understanding the role of infectious bursal disease virus(IBDV) to the pathogenesis of necrotic enteritis due to Clostridium perfringens(CP), all 15 day-old chickens used were divided as the following groups; A and E group with the feeding of feed contaminated with CP, B group with oral adminstration of IBDV($50{\mu}l/head$, $10^{3.4}EID_{50}$ of $P_4$ strain) and simultaneously feeding of feed contaminated with CP, C group treated with IBDV alone, F group with the feeding of feed contaminated with CP at 3 weeks after oral inoculation of IBDV, D and G group with the feeding of normal feed as controls. In mortality, B group(30%) was not a difference compared to A group(20%)(p>0.05), but in the pathological lesions the former was more severe degree than the latter. The mortality of F group(70%) was a significant difference to those of A, B or E group (20%)(p<0.01). Also, showed much F group more marked lesions than A, B or E group. In the chickens occurred the death during the study, mean concentration of CP was reached at $10^8{\sim}10^9CFU/g$ in the intestinal contents. B group showed higher mortality and more severe pathological changes than A and E group. Consequently, the results in the study were confirmed that the IBDV could be a role as a enhancing factor in pathogenesis of necrotic enteritis due to CP under the field condition.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.154-156
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• 2019

Eikenella corrodens is Gram-negative, facultatively anaerobic, and rod-shaped bacterium. It is a part of the normal human mucosal flora that can cause several systemic diseases such as endocarditis, liver abscess, and intracranial bacterial infection. E. corrodens KCOM 3110 (= JS217) was isolated from human subgingival dental plaque of periodontitis lesion. Here, we present the complete genome sequence of E. corrodens KCOM 3110.

• Journal of Oriental Neuropsychiatry
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• v.29 no.4
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• pp.207-221
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• 2018

Objectives: The objective of this study was to observe the anti-amnesic effects of Yukmijihwang-tang (YMJHT), on the scopolamine (Sco)-induced memory impairment in C57BL/6 mice through its favorable acetylcholine (ACh). Also, to observe acetylcholinesterase (AChE) activity, Choline acetyltransferase (ChAT) mRNA expressions, and antioxidant effect. Methods: Six groups, with a total of 20 normal and 100 Sco treated mice were selected based on their body weights after 1 week of acclimatization, were used in this study as follows. Half of the mice in each group were used for passive avoidance task tests and hippocampus ACh content, AChE activity and ChAT mRNA expression measurement, and the remaining half in each group used for Morris water maze test and measurement of cerebral antioxidant defense system. Results: Amnesia due to AChE activations and destroyed cerebral cortex antioxidant defense systems were markedly and dose-dependently inhibited after 28 days of continuous oral pre-treatment with YMJHT 400, 200 and 100 mg/kg, respectively. The overall effects of YMJHT 400 mg/kg were similar to those of tacrine 10 mg/kg. Conclusions: Based on the results, it was established that oral administration of YMJHT favorably alleviates Sco-induced memory impairment, through preservation of ACh, mediated by up-regulation of ChAT mRNA expressions and related AChE inhibition and augmentation of cerebral antioxidant defense system, at least in a condition of this experiment. The overall effects of YMJHT 400 mg/kg were similar to those of tacrine 10 mg/kg.

• BMB Reports
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• v.52 no.6
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• pp.397-402
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) uses the spike (S) glycoprotein to recognize and enter target cells. In this study, we selected two epitope peptide sequences within the receptor binding domain (RBD) of the MERS-CoV S protein. We used a complex consisting of the epitope peptide of the MERS-CoV S protein and CpG-DNA encapsulated in liposome complex to immunize mice, and produced the monoclonal antibodies 506-2G10G5 and 492-1G10E4E2. The western blotting data showed that both monoclonal antibodies detected the S protein and immunoprecipitated the native form of the S protein. Indirect immunofluorescence and confocal analysis suggested strong reactivity of the antibodies towards the S protein of MERS-CoV virus infected Vero cells. Furthermore, the 506-2G10G5 monoclonal antibody significantly reduced plaque formation in MERS-CoV infected Vero cells compared to normal mouse IgG and 492-1G10E4E2. Thus, we successfully produced a monoclonal antibody directed against the RBD domain of the S protein which could be used in the development of diagnostics and therapeutic applications in the future.

• Journal of Environmental Science International
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• v.32 no.1
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• pp.67-76
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• 2023

Under constant environmental pollution, the incidence of Atopic Dermatitis (AD) caused by air pollutants and allergens has increased. AD is an allergy inflammatory skin disease characterized by pruritus, eczema, and skin dryness. In herbal medicine, Anemarrhena asphodeloides (Anemarrhenae Rhizoma; AR) has been utilized to treat Alzheimer's disease, osteoporosis, hypertension, and inflammation. The purpose of study evaluated the effect of AR in a mouse model of 2,4-dinitrochlorobenzene (DNCB)-induced AD-like skin lesions. After acclimatization for 5 days, the mice (6-week-old, male Balb/c) were divided into five groups (n=6/group): NC (normal control), DNCB (control), Dex (5 mg·kg-1, p.o.), AR100 (100 mg·kg-1, p.o.), and AR300 (300 mg·kg-1, p.o.). On days 1 and 3, 1% DNCB was applied to the skin and ears. After 4 days, 0.5% DNCB was applied once every 2 days for 2 weeks. Then, skin and ears eczema area and severity index (EASI); skin nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2) levels; and plasma immunoglobulin E (IgE) levels were examined. The AR groups showed lower EASI, skin and ear thickness, mast cell count, and IgE levels than the control groups. Moreover, AR reduced iNOS, COX-2, and PGE2 levels. Therefore, AR possesses anti-inflammatory properties and can improve skin damage, indicating its therapeutic potential against AD.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.3
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• pp.801-825
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• 2024

For Internet of Things, it is more preferred to have immediate access to environment information from sensor nodes (SNs) rather than from gateway nodes (GWNs). To fulfill the goal, mutual authentication scheme between user and SNs with session key (SK) negotiation is more suitable. However, this is a challenging task due to the constrained power, computation, communication and storage resources of SNs. Though lots of authentication schemes with SK negotiation have been designed to deal with it, they are still insufficiently secure and/or efficient, and some even have serious vulnerabilities. Therefore, we design an efficient secure authentication scheme with session key negotiation (eSAS2KN) for wireless sensor networks (WSNs) utilizing fuzzy extractor technique, hash function and bitwise exclusive-or lightweight operations. In the eSAS2KN, user and SNs are mutually authenticated with anonymity, and an SK is negotiated for their direct and instant communications subsequently. To prove the security of eSAS2KN, we give detailed informal security analysis, carry out logical verification by applying BAN logic, present formal security proof by employing Real-Or-Random (ROR) model, and implement formal security verification by using AVISPA tool. Finally, computation and communication costs comparison show the eSAS2kN is more efficient and secure for practical application.

• Molecules and Cells
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• v.47 no.1
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• pp.100001.1-100001.8
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• 2024

In eukaryotes, a primary protein quality control (PQC) process involves the destruction of conformationally misfolded proteins through the ubiquitin-proteasome system. Because approximately one-third of eukaryotic proteomes fold and assemble within the endoplasmic reticulum (ER) before being sent to their destinations, the ER plays a crucial role in PQC. The specific functions and biochemical roles of several E3 ubiquitin ligases involved in ER-associated degradation in mammals, on the other hand, are mainly unknown. We identified 2 E3 ligases, ubiquitin protein ligase E3 component N-recognin 1 (UBR1) and ubiquitin protein ligase E3 component N-recognin 2 (UBR2), which are the key N-recognins in the N-degron pathway and participate in the ER stress response in mammalian cells by modulating their stability. Cells lacking UBR1 and UBR2 are hypersensitive to ER stress-induced apoptosis. Under normal circumstances, these proteins are polyubiquitinated through Lys48-specific linkages and are then degraded by the 26S proteasome. In contrast, when cells are subjected to ER stress, UBR1 and UBR2 exhibit greater stability, potentially as a cellular adaptive response to stressful conditions. Although the precise mechanisms underlying these findings require further investigation, our findings show that cytoplasmic UBR1 and UBR2 have anti-ER stress activities and contribute to global PQC in mammals. These data also reveal an additional level of complexity within the mammalian ER-associated degradation system, implicating potential involvement of the N-degron pathway.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.7 no.2
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• pp.208-221
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• 2000

The objective of this research was to compare the flushing effects using 1:1,000 diluted heparin or 0.9% normal saline in relation to needle gauge and frequency of IV medications. The comparative categories were clotting, duration of patency, and incidence of phlebitis. The design of research was a Nonequivalent Control group, Post test, Nonsynchrorized Design. The independent variable was 0.9% normal saline flushing the IV locks and the dependent variables were clotting, duration of patency, and incidence of phlebitis. Subjects were medical-surgical inpatients over 15 years old and with peripherally placed IVs who were hospitalized in a university medical center. Exclusion criteria included foreigners and those who were rejected for this research. The final sample for data analysis included 295 IV sites in 194 patients; 154 were in the saline group and 141 were in the heparin group. Subjects were assigned to have IV locks is flushed with 0.9% normal saline in the experimental group and to have IV lock flushed with 1:1,000 diluted heparin(100 units) in the control group. In order to increase reliability, the nurses who were assigned to the units involved in the study received an explanation on the standard method for locking an IV, recording method for observational data and criteria for the detection of phlebitis. Data were collected for a period of 2 weeks, from March 16, 2000 to March 29, 2000. Total duration of IV was defined the time of IV insertion to the time of discontinuation. Phlebitis was defined as the presence of the following : pain, swelling. erythema at the insertion site. Chi-square was used to determine the association between the degree of clotting, duration of patency, and incidence of phlebitis for the diluted heparin or the normal saline and needle gauge and frequency of IV medications. The results are summarized as follows : (a) There was difference in the degree of clotting between two groups($X^2=5.882$, p=.015). (b) There was no difference in the degree of duration of patency between two groups($X^2=2.439$, p=.295). (c) There was no difference in the incidence of phlebitis between two groups($X^2=0.190$, p=.663). (d) There was difference in the degree of clotting($X^2=6.209$, p=.013) and in the degree of duration of patency($X^2=6.978$, p=.031) according the needle guage between the two groups. (e) There was difference in the incidence of phlebitis($X^2=5.008$, p=.025) according to the frequencies of IV injection between two groups.

• Journal of Periodontal and Implant Science
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• v.30 no.2
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• pp.359-374
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• 2000

Cyclosporine A(CsA) is a widely used immunosuppressant for transplant patients and is also used for the treatment of a wide variety of systemic diseases with immunologic disorders. However, its use is frequently limited because of complications such as nephrotoxicity or gingival hyperplasia. Although several hypotheses have been postulated for CsA-induced gingival hyperplasia, i.e. various cytokine effects of inflammatory cells, existence of plaque or CsA itself, but its pathogenesis is still unclear. For experimental chronic CsA toxicity, salt depletion has been shown to increased susceptibility of rodents to the effects of CsA, and this maneuver facilitates production of arteriolopathy and interstitial fibrosis in kidney that mimic the changes found in human. The purpose of this study was to evaluate pathogenesis of CsA-induced gingival hyperplasia by comparing changes between CsA administration groups of normal standard diet and those of low salt diet group. Specific pathogen-free, 20 to 25 days old(120 to 150 g), male Fisher-344 rats(KIST, Korea), 120 to 150g of body weight, were assigned to four groups of six animals each after one week of adaptation period for powder food. Group 1 received olive oil($300{\mu}l/g\;of\;diet$) with normal standard diet(0.4% of sodium)(NSD). Group 2 received CsA(Cypol-N, Jonggundang, Korea; $300{\mu}g/g\;of\;diet$) with normal standard diet(NSD+CsA). Group 3 received same amount of olive oil with low salt diet(0.05 % of sodium, Teklad Premier, U.S.A.)(LSD). Group 4 received same dose of CsA with low salt diet(LSD+CsA). Rats were pair fed and were sacrificed after six weeks. Renal histologic lesions associated with CsA, consisted of cortical interstitial fibrosis, tubular atrophy and hyalinization of arterioles and the impairment of renal function including increase of serum creatinine and decrease of glomerular filtration rate was more severe in low salt diet group. These were proved as the results of activated of renin-angiotensin system in the kidney by low salt condition. Meanwhile the degree of gingival hyperplasia at incisor and molar tooth was less severe in low salt diet group compared with normal sodium diet group. Hyperplastic gingiva showed mild epithelial hyperplasia and expanded underlyng stroma which consisted of matrix increasement, capillary proliferation and dilatation. While the number and the activation of fibroblasts were increased, inflammatory cells were rare in the stroma. The immunohistochemistry for TGF-${\beta}_1$ in the kidney and gingiva revealed stronger positive in LSD+CsA in kidney but in gingiva of NSD+CsA. These results suggested followings; Gingival hyperplasia can be developed without inflammatory cells infiltration and seemed not induced by CsA by itself. The major role for gingival hyperplasia by CsA would be the secondary effect of TGF-${\beta}$, which maybe upregulated by CsA administration. Low salt diet can attenuate this hyperplasia perhaps by decreasing the activation of $TGF-{\beta}$.