• BMB Reports
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• v.40 no.6
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• pp.853-860
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• 2007

Resistance to anticancer drugs is a major obstacle in the effective treatment of tumors. To understand the mechanisms responsible for multidrug resistance (MDR), a proteomic approach was used to identify proteins that were expressed in different levels by the adriamycinresistant human gastric cancer cell line, SGC7901/ADR, and its parental cell line, SGC7901. Two-dimensional gel electrophoresis (2-DE) and image analysis was used to determine which protein spots were expressed in different levels by the two cell lines. These spots were then partially identified using ESI-Q-TOF mass spectrometry, and the differential expressional levels of the partially identified proteins were then determined by western blot analysis and real-time RT-PCR. Additionally, the association of Nucleophosmin (NPM1), a protein that was highly expressed by SGC7901/ADR, with MDR was analyzed using siRNA. As a result of this study, well-resolved, reproducible 2-DE patterns of SGC7901/ADR and SGC7901 were established, and 16 proteins that may playa role in the development of thermo resistance were identified. Additionally, suppression of NPMl expression was found to enhance adriamycin chemosensitivity in SGC7901/ADR. These results provide a fundamental basis for the elucidation of the molecular mechanism of MDR, which may assist in the treatment of gastric cancer.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1736-1748
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• 2018

Brucella abortus can survive and replicate within host macrophages, and great efforts have been made to demonstrate the genes involved in pathogenicity, such as internalization, in Brucella research. Here, intracellular responses were compared between THP-1 macrophage cells stimulated with B. abortus wild-type and four mutants (C1, C10, C27, and C32) using microarray to demonstrate the role of genes related to intracellular survival and replication. These mutants were generated by deleting genes encoding BAB_RS13225 (4-hydrobenzoate 3-monooxygenase, PHBH), BAB_RS00455 (heme exporter protein cytochrome C, CcmC), BAB_RS03675 (exopolyphosphatase, PPX), and BAB_RS13225 (peptidase M24). The results showed that mutants C1 and C10 induced significant suppression of survival levels and cytokine expression relative to wild-type in the THP-1 macrophage cells. These findings suggest that the BAB_RS13225 and BAB_RS00455 genes play important roles in survival within human macrophages. Conversely, mutants C27 and C32 induced significantly higher survival level than wild-type in the cells inhibiting cellular signal transduction. It is assumed that the BAB_RS03675 and BAB_RS13225 genes play a role in cellular resistance to B. abortus. Therefore, the disrupted genes are involved in B. abortus intracellular growth, and especially in its survival, and they could be effective targets for understanding the intracellular bacterium, B. abortus.

• Pediatric Infection and Vaccine
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• v.27 no.1
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• pp.24-34
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• 2020

The Korean Society of Pediatric Infectious Diseases and the Korea Centers for Disease Control and Prevention issued the guidelines about coronavirus disease 2019 (COVID-19) for children and adolescents. Case definitions and management of COVID-19 in neonates, infants, children and adolescents are presented in this guideline. In addition, guidelines for caregiver management are also provided. In this review, we introduce the contents of the current guidelines for COVID-19 in children and adolescents in Korea.

• The Korean Journal of Emergency Medical Services
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• v.11 no.2
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• pp.19-27
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• 2007

Purpose: By identifying the actual profile of emergency medical personnel's pre-admission infection control practices, this study intended to provide a basic reference material for the improvement and reorientation of pre-admission infection control measures, and thereby help establish an effective plan for pre-admission infection control activities. Methods: Total 119 EMT's working for Jeollabuk-do Provincial Fire Defense HQ were asked to join a structured questionnaire survey from June to August 2006. Results: 1. It was found that 56.1% respondents answered no guideline available on the prevention of infection. Out of our rescue brigade members who knew about relevant guideline available, 34.2% respondents answered that their department conducted quality control program for the guideline. 2. For protective outfit in emergency practice, it was found that most respondents put on gloves or nothing at all(38%), which was followed by sterile gloves(29.2%), disposable mask(26.9%), gown(4.3%) and protective goggle(1.6%). And it was noted that all respondents(100%) washed out any clothing contaminated with somatic secretion on their own. 3. For a question about any experience in emergency activities exposed to infectious diseases, it was found that most of all respondents(77.9%) answered 'No', which was followed by 'Don't Know'(18.6%) and Yes(3.9 %). 4. For a question about any experience in inquiring of patients about infectious diseases, it was found that most respondents(49.4%) answered 'Yes' and 'Sometimes'(9.1%). It was noted that 20.2% respondents had extra medical examination in medical institution in terms of whether they were exposed to infectious diseases, apart from regular medical examination. Conclusions: In order to protect 119 EMT's from infectious diseases, it will be necessary to acquire emergency medical staffs specializing in infection control and organize corresponding personnel training units to keep providing reorientation and evaluation. In addition, it will be also necessary to supply them with a full set personal protection apparatuses and other equipments required for disinfection and sterilization.

• Journal of Microbiology and Biotechnology
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• v.26 no.6
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• pp.1132-1139
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• 2016

Brucellosis is a zoonotic disease caused by Brucella, a genus of gram-negative bacteria. Cytokines have key roles in the activation of innate and acquired immunities. Despite several research attempts to reveal the immune responses, the mechanism of Brucella infection remains unclear. Therefore, immune responses were analyzed in mice immunized with nine recombinant proteins. Cytokine production profiles were analyzed in the RAW 264.7 cells and naive splenocytes after stimulation with three recombinant proteins, metal-dependent hydrolase (r0628), bacterioferritin (rBfr), and thiamine transporter substrate-binding protein (rTbpA). Immune responses were analyzed by ELISA and ELISpot assay after immunization with proteins in mice. The production levels of NO, TNF-α, and IL-6 were time-dependently increased after having been stimulated with proteins in the RAW 264.7 cells. In naive splenocytes, the production of IFN-γ and IL-2 was increased after stimulation with the proteins. It was concluded that two recombinant proteins, r0628 and rTbpA, showed strong immunogenicity that was induced with Th1-related cytokines IFN-γ, IL-2, and TNF-α more than Th2-related cytokines IL-6, IL-4, and IL-5 in vitro. Conversely, a humoral immune response was activated by increasing the number of antigen-secreting cells specifically. Furthermore, these could be candidate diagnosis antigens for better understanding of brucellosis.

• Gut and Liver
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• v.12 no.6
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• pp.641-647
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• 2018

Background/Aims: Helicobacter pylori eradication rates are decreasing because of increases in clarithromycin resistance. Thus, finding an easy and accurate method of detecting clarithromycin resistance is important. Methods: We evaluated 70 H. pylori isolates from Korean patients. Dual-labeled peptide nucleic acid (PNA) probes were designed to detect resistance associated with point mutations in 23S ribosomal ribonucleic acid gene domain V (A2142G, A2143G, and T2182C). Data were analyzed by probe-based fluorescence melting curve analysis based on probe-target dissociation temperatures and compared with Sanger sequencing. Results: Among 70 H. pylori isolates, 0, 16, and 58 isolates contained A2142G, A2143G, and T2182C mutations, respectively. PNA probe-based analysis exhibited 100.0% positive predictive values for A2142G and A2143G and a 98.3% positive predictive value for T2182C. PNA probe-based analysis results correlated with 98.6% of Sanger sequencing results (${\kappa}$-value=0.990; standard error, 0.010). Conclusions: H. pylori clarithromycin resistance can be easily and accurately assessed by dual-labeled PNA probe-based melting curve analysis if probes are used based on the appropriate resistance-related mutations. This method is fast, simple, accurate, and adaptable for clinical samples. It may help clinicians choose a precise eradication regimen.

• Biomolecules & Therapeutics
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• v.29 no.3
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• pp.282-289
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• 2021

A novel coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), caused a worldwide pandemic. Our aim in this study is to produce new fusion inhibitors against SARS-CoV-2, which can be the basis for developing new antiviral drugs. The fusion core comprising the heptad repeat domains (HR1 and HR2) of SARS-CoV-2 spike (S) were used to design the peptides. A total of twelve peptides were generated, comprising a short or truncated 24-mer (peptide #1), a long 36-mer peptide (peptide #2), and ten peptide #2 analogs. In contrast to SARS-CoV, SARS-CoV-2 S-mediated cell-cell fusion cannot be inhibited with a minimal length, 24-mer peptide. Peptide #2 demonstrated potent inhibition of SARS-CoV-2 S-mediated cell-cell fusion at 1 µM concentration. Three peptide #2 analogs showed IC50 values in the low micromolar range (4.7-9.8 µM). Peptide #2 inhibited the SARS-CoV-2 pseudovirus assay at IC50=1.49 µM. Given their potent inhibition of viral activity and safety and lack of cytotoxicity, these peptides provide an attractive avenue for the development of new prophylactic and therapeutic agents against SARS-CoV-2.

• Journal of Ecology and Environment
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• v.46 no.3
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• pp.172-182
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• 2022

Background: The coronavirus problem is an ecological problem stemming from a sudden change in the relationship between parasites and hosts. Ecologists judge organisms that are established out of their original territory as exotic species. Unlike in their original habitat, these exotic species become very aggressive in their newly settled habitat. Coronavirus infection damage was bigger in Europe or the United States than that in the country of its origin, China, and its neighboring countries. Therefore, coronavirus infection damage resembles the damage due to the invasive species. Results: Exotic species are found in places with similar environmental conditions to those of their origin when introduced to other ecological regions. However, there are few ecological ill effects in their place of origin, while the damage is usually severe in the ecological regions in which it is introduced. According to historical records, exotic infectious diseases, such as European smallpox and measles, also showed a similar trend and caused great damage in newly established places. Therefore, it is expected that measures to manage exotic species could be used for the prevention of exotic infectious diseases such as the coronavirus. Conclusions: Prevention comes first in the management of exotic species, and in order to come up with preventive measures, it is important to collect information on the characteristics of related organisms and their preferred environment. In this respect, ecosystem management measures such as exotic species management measures could be used as a reference to prevent and suppress the spread. To put these measures into practice, it is urgently required to establish an international integrated information network for collecting and exchanging information between regions and countries. Furthermore, a systematic ecosystem-management strategy in which natural and human environments could continue sustainable lives in their respective locations may serve as a countermeasure to prevent infectious diseases.

• Journal of Medicine and Life Science
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• v.19 no.3
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• pp.103-108
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• 2022

In 2021,the incidence of newly notified tuberculosis in Jeju Province decreased by 23.0% compared to that in the previous year. This was the largest decline among the 18 municipalities studied. This study aimed to examine trends in the incidence of tuberculosis among different age and sex groups in Jeju Province between 2017 and 2021. This study observed the number of new cases in the annual report from 2017 to 2021, published by the Jeju Center for Infectious Diseases Control and Prevention. The average annual percentage change (AAPC; %) was calculated to determine the trend in crude incidence rates over the past 5 years by sex and age. While a P-value of <0.1 was considered marginally significant, aP-value of <0.05 was considered statistically significant. The AAPC of all age groups in Jeju Province had negative values. In men,there was a statistically significant decrease in ages 30-34, 40-44, 45-49, and 50-54 years and a marginally significant decrease in ages 35-59, 55-59, 60-64, 65-69, 75-79, and ≥80 years. In women, a statistically significant decrease was observed among patients aged 30-34, 35-39, and ≥80 years, and a marginally significant decrease was observed among patients aged 45-49, 50-54, 60-64, 65-69, and 75-79 years. A statistically significant decrease in tuberculosis was observed among patients in their 30s and 40s, and elderly patients aged ≥80 years comprised the group vulnerable to tuberculosis. Based on these findings, tuberculosis prevention and screening programs conducted in Jeju Province were effective.

• Journal of Preventive Veterinary Medicine
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• v.43 no.4
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• pp.214-220
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• 2019

Although canine brucellosis has been known to be an important re-emerging zoonosis, the pathophysiological mechanisms of Brucella canis infection remains clues to be solved. Different culture models, single and co-culture models, were constructed with canine epithelial cells, D17 and macrophage, DH82 to investigate the induction of immune responses in in vivo B. canis infection. Expression of genes related with induction of immune responses, Th1, Th2 and Th17, was compared in the two different models after the bacterial infection. In this study, expression of cytokine genes, IL-1β, IL-5, IL-6, IL-10, IL-23, and TNF-α was quantified in the DH82 at different time points using RT-qPCR in the two different culture systems after the infection. Cytokine genes related with Th1, IL-1β and TNF-α and Th17, IL-6 and IL-23 were expressed with time-dependent manners in the both systems (p<0.05). However, increase of Th2-related cytokine genes expression was not detectable in the both systems by comparison with control. The expression of Th1 and Th17 related cytokine genes was earlier in single cell culture than those in co-culture model (p<0.05). In general, amounts of the expressed genes were shown higher in single cell model than those in co-culture models. This study indicate that Th1 and Th17-associated immune responses are central to B. canis infection in dogs. In addition, it suggests a specific role of epithelial cells in the B. canis infection in vivo, which should resolved in the further study.