86 results on '"Young Yil Bahk"'
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2. An Evaluation of a New Quantitative Point-of Care Diagnostic to Measure Glucose-6-phosphate Dehydrogenase Activity
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Young Yil Bahk, Seong Kyu Ahn, Heung Jin Jeon, Byoung-Kuk Na, Sung-Keun Lee, and Ho-Joon Shin
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Antimalarials ,Glucosephosphate Dehydrogenase Deficiency ,Infectious Diseases ,Point-of-Care Systems ,Malaria, Vivax ,Humans ,Parasitology ,Primaquine ,Reagent Kits, Diagnostic ,Glucosephosphate Dehydrogenase ,Malaria - Abstract
Malaria continues to be one of the most crucial infectious burdens in endemic areas worldwide, as well as for travelers visiting malaria transmission regions. It has been reported that 8-aminoquinolines are effective against the Plasmodium species, particularly primaquine, for anti-hypnozoite therapy in P. vivax malaria. However, primaquine causes acute hemolytic anemia in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. Therefore, G6PD deficiency testing should precede hypnozoite elimination with 8-aminoquinoline. Several point-of-care devices have been developed to detect G6PD deficiency. The aim of the present study was to evaluate the performance of a novel, quantitative G6PD diagnostics based on a metagenomic blue fluorescent protein (mBFP). We comparatively evaluated the sensitivity and specificity of the G6PD diagnostic modality with standard methods using 120 human whole blood samples. The G6PD deficiency was spectrophotometrically confirmed. The performance of the G6PD quantitative test kit was compared with that of a licensed control medical device, the G6PD strip. The G6PD quantitative test kit had a sensitivity of 95% (95% confidence interval (CI): 89.3-100%) and a specificity of 100% (95% CI: 94.3-100%). This study shows that the novel diagnostic G6PD quantitative test kit could be a cost-effective and time-efficient, and universally mandated screening tool for G6PD deficiency.
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- 2022
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3. Supplementary Table 1 from Pierce1, a Novel p53 Target Gene Contributing to the Ultraviolet-Induced DNA Damage Response
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Han-Woong Lee, Young Yil Bahk, Kunsoo Rhee, Jaehoon Lee, Jusik Roh, Sushil Devkota, Hye Jin Kim, and Young Hoon Sung
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Supplementary Table 1 from Pierce1, a Novel p53 Target Gene Contributing to the Ultraviolet-Induced DNA Damage Response
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- 2023
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4. Supplementary Figure Legends 1-6 from Pierce1, a Novel p53 Target Gene Contributing to the Ultraviolet-Induced DNA Damage Response
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Han-Woong Lee, Young Yil Bahk, Kunsoo Rhee, Jaehoon Lee, Jusik Roh, Sushil Devkota, Hye Jin Kim, and Young Hoon Sung
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Supplementary Figure Legends 1-6 from Pierce1, a Novel p53 Target Gene Contributing to the Ultraviolet-Induced DNA Damage Response
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- 2023
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5. Knowledge, Attitudes and Perceptions Regarding Endemic Vivax Malaria in Inhabitants and Patients in Two Cities of Northern Gyeonggi-do, Korea, 2020
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Young Yil Bahk, Shin-Hyeong Cho, Sookkyung Park, Jeongran Kwon, Hyesu Kan, Miyoung Kim, Byoung-Kuk Na, Sung Jong Hong, Hyung Wook Kwon, and Tong-Soo Kim
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Health Knowledge, Attitudes, Practice ,questionnaire ,perception ,Infectious Diseases ,attitude ,Vivax malaria ,Republic of Korea ,parasitic diseases ,Malaria, Vivax ,Animals ,Humans ,Original Article ,malaria knowledge ,Parasitology ,Cities ,Plasmodium vivax - Abstract
An understanding of the knowledges, attitudes and perceptions of different populations is key for public health policy makers. Here, a survey was performed on knowledge, attitudes, and perceptions about malaria diagnosis, prevention, control, and treatment. The 407 survey participants included both uninfected inhabitants and patients from 2 cities (Gimpo- and Paju-si) of Northern Gyeonggi-do, known as high-risk areas for vivax malaria. We used community-based study design and non-probability sampling method using the primary data. Association between variables were tested using χ2-tests. In general, the information on malaria reported by the participants in this study was unsystematic and included inaccurate details. The knowledge of malaria symptoms, identified as headache, chills and fever, was high, but the surveyed community lacks knowledge of the specific medications used for malaria treatment, with a large number of respondents having no knowledge of any form of medication. Survey questions with high correct answer rates included questions about easy treatment of malaria in Korea, the high daytime activity of malaria-borne mosquitoes, and the infection risk posed by outdoor activities. However, a large portion of the respondents was unable to provide simple medical and biological information about the disease. This study aimed to comprehensively evaluate the knowledge, attitude, and practical behavior of the surveyed community with respect to malaria and the implications reported here could be applicable to other malaria endemic areas in Korea.
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- 2021
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6. Awareness and Opinions of Inhabitants on Vivax Malaria in Two Endemic Areas, Gyeonggi-do, Korea
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Sung Jong Hong, Tong-Soo Kim, Shin-Hyeong Cho, Byoung-Kuk Na, Young Yil Bahk, and Sung-Keun Lee
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medicine.medical_specialty ,Antibodies, Protozoan ,Brief Communication ,Environmental health ,Malaria elimination ,Republic of Korea ,Vivax malaria ,parasitic diseases ,Health care ,Malaria, Vivax ,medicine ,Humans ,awareness ,education ,endemicity ,business.industry ,Public health ,Incidence (epidemiology) ,public health ,Malaria ,Infectious Diseases ,Geography ,Parasitology ,Malaria prevention ,Plasmodium vivax ,business - Abstract
The incidence of vivax malaria in Korea was reduced to a low plateau. For successful elimination of vivax malaria, socio-behavioral changes in the communities are essential. This study aimed to figure out awareness of the inhabitants on the vivax malaria endemicity. The 407 participants including vivax malaria patients and uninfected inhabitants in Gimpo- and Paju-si, Gyeonggi-do, known as high-risk areas in Korea. We used a community-based study design and non-probability sampling method using primary data. Except for the perception about the public health facilities’ capability to cope with anti-malaria programs, the 2 groups of participants shared the same level of awareness about public promotional and educational measures and opinions for malaria elimination from the community. Thus, our future goals for malaria prevention and elimination are to develop more active and well-organized community-based education and evaluation programs collaborating with the community healthcare authorities and local governments.
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- 2021
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7. Hard Ticks as Vectors Tested Negative for Severe Fever with Thrombocytopenia Syndrome in Ganghwa-do, Korea during 2019-2020
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Tong-Soo Kim, Young Woo Gong, Seong Kyu Ahn, Jung-Hwan Lim, Kyoung Jin, Joonghee Cho, Mun Ju Kwon, Young Yil Bahk, Yeon-Ja Koh, Jin-Young Lee, Jaeyong Song, and Hyung Wook Kwon
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Phlebovirus ,0301 basic medicine ,Veterinary medicine ,Monitoring ,Ixodidae ,Severe Fever with Thrombocytopenia Syndrome ,030231 tropical medicine ,030106 microbiology ,Tick ,03 medical and health sciences ,Ticks ,0302 clinical medicine ,Republic of Korea ,medicine ,Animals ,Ganghwa-do ,Korea ,Ixodes nipponensis ,SFTS ,biology ,medicine.disease ,biology.organism_classification ,Severe fever with thrombocytopenia syndrome ,Infectious Diseases ,Original Article ,Parasitology ,Haemaphysalis longicornis ,hard tick ,Severe fever with thrombocytopenia syndrome virus ,Hard ticks - Abstract
This study aimed to characterize the seasonal abundance of hard ticks that transmit severe fever with thrombocytopenia syndrome virus from April to November 2019 and 2020 on Ganghwa-do, Incheon Metropolitan City, Korea. The ticks were collected at grassland, grave site, copse and mountain road using a collection trap method. The ixodid hard ticks comprising three species (Haemaphysalis longicornis, H. flava, and Ixodes nipponensis) collected were 6,622 in 2019 and 3,811 in 2020. H. longicornis was the most frequent (97.9% in 2019 and 96.0% in 2020), followed by H. flava (2.0% and 3.0% in 2019 and 2020, respectively) and I. nipponensis (less than 0.1%). Our study demonstrated that seasonal patterns of the tick populations examined for two years were totally unsimilar. The hard ticks tested using RT-qPCR were all negative for severe fever with thrombocytopenia syndrome virus.
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- 2021
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8. Occurrence of four waterborne viruses at five typical raw water resources in the Republic of Korea during August 2013 to February 2019
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Min-Ho Kim, Sang Jung Park, Ok-Jae Rhee, Tong-Soo Kim, Sang-Seob Lee, Jeong-Myeong Kim, and Young Yil Bahk
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Veterinary medicine ,viruses ,Indicator bacteria ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Microbiology ,03 medical and health sciences ,Rotavirus ,Republic of Korea ,Waterborne Diseases ,medicine ,Humans ,Raw water ,030304 developmental biology ,0303 health sciences ,biology ,030306 microbiology ,Waterborne diseases ,General Medicine ,biology.organism_classification ,medicine.disease ,Water resources ,Lakes ,Viruses ,Norovirus ,Enterovirus ,Water Microbiology ,Geum ,Environmental Monitoring - Abstract
Waterborne diseases have critical public health issues and socioeconomic relevancy worldwide. Various viral pathogens are ordinarily associated with waterborne diseases. Six-year-surveillance (a total of 20 times) of norovirus, hepatitis A virus, group C rotavirus, and enterovirus was conducted at five raw water sampling sites including two lakes (Lakes Soyang and Juam), Hyundo region of Geum River in Daejeon City, and Guui region of Han River in Seoul Metropolitan City and Moolgeum region of Nakdong River in Gimhae City which are located near two water intake plants. In this study, we routinely investigated virus contamination in water samples through reverse transcription polymerase chain reaction (RT-PCR) and integrated cell culture RT-PCR with high sensitivity and specificity. A total 100 samples were tested. Most of the targeted viruses were found in 32% of the samples and at least one of the indicator bacteria was detected in 65% of these occurrences. Among all the detected viruses, enterovirus was the most prevalent with a detection frequency of 12% and 2.71 MPN/10 L on average, while hepatitis A virus was the least prevalent with a detection frequency of 4%. Nearly all of the analyzed viruses (except for group C rotavirus) were present in samples from Han River (the Guui region), Geum River (the Hyundo region), Lake Juam, and Nakdong River (the Moolgeum region), while group C rotavirus was detected in those from the Guui region. During the six-year sampling period, the targeted waterborne viruses in water samples exhibited seasonal patterns in their occurrence that were different from the indicator bacteria levels in the water samples. The fact that they were detected in the five representative Korean water environments makes it necessary to establish the chemical and biological analysis systems for waterborne viruses and sophisticated management systems.
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- 2020
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9. Long-Term Monitoring of Noxious Bacteria for Construction of Assurance Management System of Water Resources in Natural Status of the Republic of Korea
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Ok-Jae Rhee, Tong-Soo Kim, Kyung Seon Bae, Woojoo Lee, Sang-Seob Lee, Kyung-A You, Young Yil Bahk, and Hyun-Sook Kim
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0106 biological sciences ,Veterinary medicine ,Chemical Phenomena ,Shigella sonnei ,Indicator bacteria ,Escherichia coli O157 ,01 natural sciences ,Applied Microbiology and Biotechnology ,Campylobacter jejuni ,Legionella pneumophila ,Rivers ,Water Quality ,010608 biotechnology ,Republic of Korea ,Raw water ,Vibrio cholerae ,biology ,Salmonella enterica ,General Medicine ,biology.organism_classification ,Water resources ,Water Resources ,Water Microbiology ,Geum ,Bacteria ,Biotechnology - Abstract
Climate change is expected to affect not only availability and quality of water, the valuable resource of human life on Earth, but also ultimately public health issue. A six-year monitoring (total 20 times) of Escherichia coli O157, Salmonella enterica, Legionella pneumophila, Shigella sonnei, Campylobacter jejuni, and Vibrio cholerae was conducted at five raw water sampling sites including two lakes, Hyundo region (Geum River) and two locations near Water Intake Plants of Han River (Guui region) and Nakdong River (Moolgeum region). A total 100 samples of 40 L water were tested. Most of the targeted bacteria were found in 77% of the samples and at least one of the target bacteria was detected (65%). Among all the detected bacteria, E. coli O157 were the most prevalent with a detection frequency of 22%, while S. sonnei was the least prevalent with a detection frequency of 2%. Nearly all the bacteria (except for S. sonnei) were present in samples from Lake Soyang, Lake Juam, and the Moolgeum region in Nakdong River, while C. jejuni was detected in those from the Guui region in Han River. During the six-year sampling period, individual targeted noxious bacteria in water samples exhibited seasonal patterns in their occurrence that were different from the indicator bacteria levels in the water samples. The fact that they were detected in the five Korea’s representative water environments make it necessary to establish the chemical and biological analysis for noxious bacteria and sophisticated management systems in response to climate change.
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- 2020
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10. Monitoring Culicine Mosquitoes (Diptera: Culicidae) as a Vector of Flavivirus in Incheon Metropolitan City and Hwaseong-Si, Gyeonggi-Do, Korea, during 2019
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Jong Myong Park, Seong Kyu Ahn, Sung Suck Oh, Eun-Jeong Choi, Hojong Jun, Tong-Soo Kim, Myung-Deok Kim-Jeon, Young Woo Gong, Seo Hye Park, Young Yil Bahk, Bag-Sou Moon, Mun Ju Kwon, Haneul Jung, Jin-Young Lee, and Kyung-Ae Kim
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Veterinary medicine ,insect-specific flavivirus ,Time Factors ,Culex ,viruses ,030231 tropical medicine ,Population ,Biology ,Tick ,03 medical and health sciences ,0302 clinical medicine ,Mosquito ,Republic of Korea ,parasitic diseases ,Animals ,Humans ,education ,030304 developmental biology ,Aedes vexans ,0303 health sciences ,education.field_of_study ,Reverse Transcriptase Polymerase Chain Reaction ,Flavivirus ,fungi ,Anopheles ,biology.organism_classification ,Insect Vectors ,climate change ,Culicidae ,Infectious Diseases ,Vector (epidemiology) ,surveillance ,RNA, Viral ,Original Article ,Parasitology ,Cdna sequencing ,Environmental Monitoring - Abstract
The flaviviruses are small single-stranded RNA viruses that are typically transmitted by mosquitoes or tick vectors and are etiological agents of acute zoonotic infections. The viruses are found around the world and account for significant cases of human diseases. We investigated population of culicine mosquitoes in central region of Korean Peninsula, Incheon Metropolitan City and Hwaseong-si. Aedes vexans nipponii was the most frequently collected mosquitoes (56.5%), followed by Ochlerotatus dorsalis (23.6%), Anopheles spp. (10.9%), and Culex pipiens complex (5.9%). In rural regions of Hwaseong, Aedes vexans nipponii was the highest population (62.9%), followed by Ochlerotatus dorsalis (23.9%) and Anopheles spp. (12.0%). In another rural region of Incheon (habitat of migratory birds), Culex pipiens complex was the highest population (31.4%), followed by Ochlerotatus dorsalis (30.5%), and Aedes vexans vexans (27.5%). Culex pipiens complex was the predominant species in the urban region (84.7%). Culicine mosquitoes were identified at the species level, pooled up to 30 mosquitoes each, and tested for flaviviral RNA using the SYBR Green-based RT-PCR and confirmed by cDNA sequencing. Three of the assayed 2,683 pools (989 pools without Anopheles spp.) were positive for Culex flaviviruses, an insect-specific virus, from Culex pipiens pallens collected at the habitats for migratory birds in Incheon. The maximum likelihood estimation (the estimated number) for Culex pipiens pallens positive for Culex flavivirus was 25. Although viruses responsible for mosquito-borne diseases were not identified, we encourage intensified monitoring and long-term surveillance of both vector and viruses in the interest of global public health.
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- 2020
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11. Flaviviral disease mosquito vector surveillance in Incheon Metropolitan City and the Hwaseong area, Gyeonggi‐Do, Republic of Korea, in 2015
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Seong Kyu Ahn, Young Yil Bahk, Jong Yul Roh, Young Woo Gong, Myung-Deok Kim-Jeon, Seung Jegal, Mun Ju Kwon, Jin-Young Lee, Tong-Soo Kim, Wook-Gyo Lee, Seo Hye Park, and Hojong Jun
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0106 biological sciences ,0303 health sciences ,Veterinary medicine ,ved/biology ,ved/biology.organism_classification_rank.species ,Disease ,Biology ,Japanese encephalitis ,biology.organism_classification ,medicine.disease ,01 natural sciences ,Metropolitan area ,Anopheles sinensis ,010602 entomology ,03 medical and health sciences ,Flavivirus ,Insect Science ,Vector (epidemiology) ,Genotype ,medicine ,030304 developmental biology ,Aedes vexans - Abstract
Owing to global climate change, the global resurgence of vector‐borne infectious diseases and their potential to inflict widespread casualties among human populations has emerged as a pivotal burden on public health systems. In this study, the prevalence of flaviviral diseases transmitted by mosquitoes, and their target vector diversity, abundance, and distribution was investigated to enable the mapping of hotspots for these diseases. For the surveillance of the vector mosquitoes carrying flaviviruses during April to November 2015, female mosquitoes were collected to study whether they carried pathogens from abroad at seven locations in Incheon Metropolitan City (Incheon) as a typical urban area and Hwaseong‐si (= city, Hwaseong) of Gyeonggi‐do (= province) as a rural area. A total of 15 species belonging to seven genera (29,102 female mosquitoes) were collected with black‐light and BG‐Sentinel™ traps at a collection rate of 260 per trap/night from whole collection locations. The most collected mosquito species in Incheon were Aedes vexans nipponii (species ratio (SR), 29.9%) and the Culex pipiens complex (SR, 28.8%), followed by Anopheles sinensis s.l. (SR, 27.9%) and Ochlerotatus koreicus (SR, 7.1%). From the results of viral RNA detection, five flaviviruses were found in 20,981 individuals (excluding An. sinensis; 696 pools) in the Cx. pipiens complex and Ae. vexans nipponii. Three Japanese encephalitis virus (JEV)‐positive pools were from the Cx. pipiens complex, a Chaoyang virus pool was found from Ae. vexans nipponii, and the remaining unidentified flavivirus pool was from Cx. pipiens. The three JEV‐positive pools were phylogenetically grouped as genotype V. The results of our study demonstrate that enhanced monitoring and long‐term surveillance of these vector viruses are of great public health importance.
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- 2020
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12. Four Year Surveillance of the Vector Hard Ticks for SFTS, Ganghwa-do, Republic of Korea
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Jong Yul Roh, Wook-Gyo Lee, Jin-Young Lee, Tong-Soo Kim, Seo Hye Park, Young Yil Bahk, Haneul Jung, Young Woo Gong, Myung-Deok Kim-Jeon, Seong Kyu Ahn, Seung Jegal, Hojong Jun, Mun Ju Kwon, and Kwangsig Joo
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Male ,Phlebovirus ,0301 basic medicine ,Hard tick ,Veterinary medicine ,Ixodidae ,Population Dynamics ,030106 microbiology ,030231 tropical medicine ,Disease Vectors ,03 medical and health sciences ,0302 clinical medicine ,Republic of Korea ,Animals ,Humans ,severe fever with thrombocytopenia syndrome (SFTS) ,Nymph ,Ganghwa-do ,Larva ,Ixodes nipponensis ,biology ,SFTS virus ,biology.organism_classification ,climate change ,Phlebotomus Fever ,Infectious Diseases ,Vector (epidemiology) ,Original Article ,Arachnid Vectors ,Female ,Parasitology ,Seasons ,Haemaphysalis longicornis ,Hard ticks - Abstract
The seasonal abundance of hard ticks that transmit severe fever with thrombocytopenia syndrome virus was monitored with a collection trap method every April to November during 2015-2018 and with a flagging method every July and August during 2015-2018 in Ganghwa-do (island) of Incheon Metropolitan City, Republic of Korea. This monitoring was performed in a copse, a short grass field, coniferous forest and broad-leaved forest. A total of 17,457 ticks (8,277 larvae, 4,137 nymphs, 3,389 females, and 1,654 males) of the ixodid ticks comprising 3 species (Haemaphysalis longicornis, H. flava, and Ixodes nipponensis) were collected with collection traps. Of the identified ticks, H. longicornis was the most frequently collected ticks (except larval ticks) (94.26%, 8,653/9,180 ticks (nymphs and adults)), followed by H. flava (5.71%, 524/9,180) and Ix. nipponensis (less than 0.04%, 3/9,180). The ticks collected with collecting traps were pooled and assayed for the presence of SFTS virus with negative results. In addition, for monitoring the prevalence of hard ticks, a total of 7,461 ticks (5,529 larvae, 1,272 nymphs, 469 females, and 191 males) of the ixodid ticks comprising 3 species (H. longicornis, H. flava, and Ix. nipponensis) were collected with flagging method. H. longicornis was the highest collected ticks (except larval ticks) (99.53%, 1,908/1,917 ticks (nymphs and adults)), followed by H. flava (1.15%, 22/1,917).
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- 2019
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13. Three‐year surveillance (2016–2018) of chigger mites vector for tsutsugamushi disease in the Hwaseong‐Si area of Gyeonggi‐Do, Republic of Korea
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Seo Hye Park, Hojong Jun, Young Yil Bahk, Tong-Soo Kim, Seong Kyu Ahn, Jong Yul Roh, Young Woo Gong, Myung-Deok Kim-Jeon, Jin-Young Lee, Mun Ju Kwon, Seung Jegal, and Wook-Gyo Lee
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0106 biological sciences ,Apodemus agrarius ,0303 health sciences ,Orientia tsutsugamushi ,biology ,Rodent ,Host (biology) ,Zoology ,Scrub typhus ,bacterial infections and mycoses ,medicine.disease ,biology.organism_classification ,01 natural sciences ,Neotrombicula ,010602 entomology ,03 medical and health sciences ,Insect Science ,Vector (epidemiology) ,biology.animal ,medicine ,Mite ,030304 developmental biology - Abstract
Owing to climate change, the global resurgence of vector‐borne infectious diseases has emerged as a critical public health issue. Orientia tsutsugamushi is the etiological agent of tsutsugamushi disease (scrub typhus) a mite‐borne acute febrile disease occurring in the Asia‐Pacific region. We investigated the prevalence of tsutsugamushi disease transmitted by chigger mite vectors living on rodents. Using sticky‐type chigger traps for three months during 2016–2018, 1,057 chigger mites were collected (chigger mite index, 1.31) from four locations in the Hwaseong‐si area of Gyeonggi‐do, Republic of Korea. Five species distributed among three genera were identified. In addition, 94 rodents were captured (collection rate: 7.83%) using Sherman live traps over the course of three months (April, October, and November) during 2016–2017. Three rodent species were captured and identified and the striped field mouse (Apodemus agrarius) was the dominant rodent host species in the surveyed area. A total of 10,469 ectoparasitic chigger mites were recovered from the 94 rodents, from which 13 species distributed among four genera were identified. Of the 5,250 chigger mites examined, Leptotrombidium pallidum was most abundant (n = 2,558), followed by L. orientale, L. scutellare, L. zetum, Euschoengastia koreaensis, L. subintermedium, and Neotrombicula tamiyai. Of the examined chigger mites, no groups recovered from rodent hosts tested positive for O. tsutsugamushi. This study provides fundamental regional information on vector‐borne disease data collection in the Hwaseong‐si area, Gyeonggi‐do, and will further contribute to formulating disease control and prevention strategies.
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- 2019
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14. An Epidemiological Analysis of 28 Vivax Malaria Cases in Gimpo-si, Korea, 2020
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Hyesu Kan, Byoung-Hak Jeon, Jeong-Hyun Kim, Kyoung Nam Kim, Miyoung Kim, Eun Hee Shin, Jeongran Kwon, Shin-Hyeong Cho, Young Yil Bahk, S. W. Park, and Tong-Soo Kim
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medicine.medical_specialty ,Pediatrics ,Disease ,Parasitemia ,Brief Communication ,Incubation period ,Gimpo-si ,Epidemiology ,parasitic diseases ,Republic of Korea ,medicine ,Malaria, Vivax ,vivax malaria ,Humans ,business.industry ,Public health ,focused interview ,medicine.disease ,Infectious Diseases ,Vivax malaria ,Parasitology ,Chills ,Epidemiologic analysis ,medicine.symptom ,business ,Plasmodium vivax ,Malaria - Abstract
Since 1993, vivax malaria has been recognized as a public health burden in Korea. Despite of pan-governmental malaria-control efforts and the dramatic reduction in the burden of this disease over the last 10 years, vivax malaria has not been well controlled and has remained continuously endemic. We focused interviewed and examined the charts of 28 confirmed vivax malaria patients given malarial therapy for whom daily records were kept from Gimpo-si, Gyeonggido of Korea. Various epidemiological characteristics of vivax malaria, including the incubation period, medication used, and recurrence, and an evaluation of the parasitic characteristics from the focused interviews of patients from this region are described here. Most of the participants indicated the 3 most common symptoms of malaria (headache, chills and fever). Of the 28 cases, 2 experienced a second attack and there were 17 and 11 cases with short- and long-term incubation periods, respectively, yielding a short-term to long-term ratio of 1.5. Based on the parasitemia stages, most of the participants were tested at 5 to 7 days (11 cases) and 7 to 15 days (11 cases) after initial wave of asexual parasites. In conclusion, public health authorities should consider developing management measures to decrease the time lag for diagnosis and drafting unified and robust guidelines for drug use for malaria and drawing up unified and robust guidelines on the use of medication for malaria. It also suggests that routine monitoring, surveillance, and precise medical surveys in high-risk vivax malaria endemic areas are pivotal to controlling this persistent public disease and finally eliminating it from Korea.
- Published
- 2021
15. Surveillance of Chigger Mite Vectors for Tsutsugamushi Disease in the Hwaseong Area, Gyeonggi-do, Republic of Korea, 2015
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Young Yil Bahk, Tong-Soo Kim, Mun Ju Kwon, Kwangsig Joo, Young Woo Gong, Wook-Gyo Lee, Seo Hye Park, Hojong Jun, Seong Kyu Ahn, Haneul Jung, Jong Yul Roh, Myung-Deok Kim-Jeon, Jin-Young Lee, and Seung Jegal
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Apodemus agrarius ,Veterinary medicine ,Orientia tsutsugamushi ,Time Factors ,030231 tropical medicine ,Scrub typhus ,Trombiculidae ,Neotrombicula ,03 medical and health sciences ,0302 clinical medicine ,Republic of Korea ,Mite ,medicine ,Animals ,Humans ,Hwaseong ,030212 general & internal medicine ,Mites ,Communicable disease ,Korea ,biology ,chigger mite ,tsutsugamushi disease ,biology.organism_classification ,medicine.disease ,bacterial infections and mycoses ,Infectious Diseases ,Scrub Typhus ,Vector (epidemiology) ,Parasitology ,Crocidura lasiura ,Arachnid Vectors ,Original Article ,Murinae ,vector - Abstract
Owing to global climate change, the global resurgence of vector-borne infectious diseases and their potential to inflict widespread casualties among human populations has emerged as a pivotal burden on public health systems. Tsutsugamushi disease (scrub typhus) in the Republic of Korea is steadily increasing and was designated as a legal communicable disease in 1994. The disease is a mite-borne acute febrile disease most commonly contracted from October to December. In this study, we tried to determine the prevalence of tsutsugamushi disease transmitted by chigger mites living on rodents and investigated their target vector diversity, abundance, and distribution to enable the mapping of hotspots for this disease in 2015. A total of 5 species belonging to 4 genera (109 mites): Leptotrombidium scutellare 60.6%, L. pallidum 28.4% Neotrombicula tamiyai 9.2%, Euschoengastia koreaensis/0.9%), and Neoschoengastia asakawa 0.9% were collected using chigger mite collecting traps mimicking human skin odor and sticky chigger traps from April to November 2015. Chigger mites causing tsutsugamushi disease in wild rodents were also collected in Hwaseong for the zoonotic surveillance of the vector. A total of 77 rodents belonging to 3 genera: Apodemus agrarius (93.5%), Crocidura lasiura (5.2%), and Micromys minutus (1.3%) were collected in April, October, and November 2015. The most common mite was L. pallidum (46.9%), followed by L. scutellare (18.6%), and L. orientale (18.0%). However, any of the chigger mite pools collected from rodent hosts was tested positive for Orientia tsutsugamushi, the pathogen of tsutsugamushi disease, in this survey.
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- 2020
16. Epidemiological Characteristics of Re-emerging Vivax Malaria in the Republic of Korea (1993-2017)
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Kyoung Jin, Jeong-a Kim, Young Yil Bahk, Tong-Soo Kim, Byoung-Kuk Na, Yeong Seon Hong, and Hyeong-Woo Lee
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medicine.medical_specialty ,Endemic Diseases ,Mini Review ,030231 tropical medicine ,Plasmodium vivax ,Population ,mosquito ,Disease ,Communicable Diseases, Emerging ,re-emerging malaria ,03 medical and health sciences ,0302 clinical medicine ,Environmental health ,Republic of Korea ,parasitic diseases ,Epidemiology ,Disease Transmission, Infectious ,Malaria, Vivax ,medicine ,Humans ,030212 general & internal medicine ,education ,education.field_of_study ,biology ,Public health ,biology.organism_classification ,medicine.disease ,Infectious Diseases ,Geography ,Infectious disease (medical specialty) ,Vector (epidemiology) ,Parasitology ,control ,vector ,Malaria - Abstract
Historically, Plasmodium vivax malaria has been one of the most highly endemic parasitic diseases in the Korean Peninsula. Until the 1970s, vivax malaria was rarely directly lethal and was controlled through the Korean Government Program administered by the National Malaria Eradication Service in association with the World Health Organization's Global Malaria Eradication Program. Vivax malaria has re-emerged in 1993 near the Demilitarized Zone between South and North Korea and has since become an endemic infectious disease that now poses a serious public health threat through local transmission in the Republic of Korea. This review presents major lessons learned from past and current malaria research, including epidemiological and biological characteristics of the re-emergent disease, and considers some interesting patterns of diversity. Among other features, this review highlights temporal changes in the genetic make-up of the parasitic population, patient demographic features, and spatial distribution of cases, which all provide insight into the factors contributing to local transmission. The data indicate that vivax malaria in Korea is not expanding expo- nentially. However, continued surveillance is needed to prevent future resurgence.
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- 2018
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17. Genetic Diversity of Plasmodium vivax Causing Epidemic Malaria in the Republic of Korea
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Jong-Yil Chai, Jeong-a Kim, Byoung Kuk Na, Seong Kyu Ahn, Tong-Soo Kim, and Young Yil Bahk
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0301 basic medicine ,medicine.medical_specialty ,Mini Review ,030231 tropical medicine ,Plasmodium vivax ,Biology ,Communicable Diseases, Emerging ,Genetic diversity ,03 medical and health sciences ,0302 clinical medicine ,Environmental health ,Republic of Korea ,parasitic diseases ,Epidemiology ,Malaria, Vivax ,medicine ,Humans ,Genetic variability ,Epidemics ,Korea ,Human migration ,business.industry ,Incidence (epidemiology) ,Genetic Variation ,vivax population ,medicine.disease ,biology.organism_classification ,030104 developmental biology ,Infectious Diseases ,Vivax malaria ,Parasitology ,business ,Malaria - Abstract
Plasmodium vivax is more challenging to control and eliminate than P. falciparum due to its more asymptomatic infections with low parasite densities making diagnosis more difficult, in addition to its unique biological characteristics. The potential re-introduction of incidence cases, either through borders or via human migrations, is another major hurdle to sustained control and elimination. The Republic of Korea has experienced re-emergence of vivax malaria in 1993 but is one of the 32 malaria-eliminating countries to-date. Despite achieving successful nationwide control and elimination of vivax malaria, the evolutionary characteristics of vivax malaria isolates in the Republic of Korea have not been fully understood. In this review, we present an overview of the genetic variability of such isolates to increase understanding of the epidemiology, diversity, and dynamics of vivax populations in the Republic of Korea.
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- 2018
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18. Prevention and Control Strategies for Parasitic Infections in the Korea Centers for Disease Control and Prevention
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Jong-Yil Chai, Shin Hyeong Cho, Tong-Soo Kim, Young Yil Bahk, Eun Hee Shin, and Jung-Won Ju
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0301 basic medicine ,medicine.medical_specialty ,Surveillance of parasite ,030231 tropical medicine ,Governmental agency ,Health consciousness ,Disease Outbreaks ,03 medical and health sciences ,Elephantiasis, Filarial ,Government Agencies ,0302 clinical medicine ,Basic research ,KCDC ,Environmental health ,Republic of Korea ,Parasitic Diseases ,medicine ,Animals ,Humans ,Intestinal Diseases, Parasitic ,Lymphatic filariasis ,parasite control ,Travel ,business.industry ,Research ,Public health ,Parasite Control ,Mini-Review ,030108 mycology & parasitology ,medicine.disease ,Disease control ,Infectious Diseases ,Parasitology ,business ,Malaria - Abstract
Korea is successfully controlled intestinal parasitic infections owing to economic development and high health consciousness. The Division of Vectors and Parasitic Diseases (formerly the Division of Malaria and Parasitology) is in the Center for Laboratory Control of Infectious Diseases of the Korea Centers for Disease Control and Prevention. It has been the governmental agency responsible for controlling and leading scientific research on parasitic diseases. The Division of Vectors and Parasitic Diseases has conducted and funded basic research and disseminated the research results to various medical fields, ultimately promoting public health in Korea. Among the noteworthy achievements of this division are the national surveillance of healthcare-associated parasitic infections, prevention and control for parasitic infections, and the elimination of lymphatic filariasis from Korea. On a broader scale, the division's research programs and academic supports were influential in preventing and treating infectious parasitic diseases through public policies and laws. In this review, we summarize the past and present role of the Division of Vectors and Parasitic Diseases in preventing and treating infectious parasitic diseases in Korea.
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- 2018
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19. Survey on Intestinal Helminthic Infection Status of Students in Two Counties, Hadong-gun and Goseong-gun, Korea
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Woon-Mok Sohn, Young Yil Bahk, Sung-Jong Hong, Tong-Soo Kim, Yun-Kyu Park, Byoung-Kuk Na, and Jong-Yil Chai
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Male ,0301 basic medicine ,Veterinary medicine ,student ,Time Factors ,Adolescent ,ved/biology.organism_classification_rank.species ,Helminthiasis ,Parasitic infection ,law.invention ,Feces ,03 medical and health sciences ,0302 clinical medicine ,Food Parasitology ,law ,Republic of Korea ,parasitic diseases ,Prevalence ,Animals ,Humans ,Helminths ,egg-positive ,survey ,030212 general & internal medicine ,Trichiura ,Intestinal Diseases, Parasitic ,Intestinal helminthic ,Child ,Students ,Heterophyidae ,Parasite Egg Count ,Clonorchis sinensis ,Schools ,biology ,ved/biology ,Fishes ,Metagonimus yokogawai ,030108 mycology & parasitology ,biology.organism_classification ,Infectious Diseases ,Transmission (mechanics) ,Trichuris trichiura ,Original Article ,endemic ,Female ,Parasitology ,non-endemic - Abstract
This study was conducted to investigate the prevalence of intestinal parasites among students from Goseong-gun, Gangwon-do and Hadong-gun, Gyeongsangnam-do as typical low and high endemic counties. From May to July 2017, a total of 2,033 fecal samples were collected at 27 elementary, 10 junior high, and 8 high schools from 2 counties and examined by the Kato-Katz technique for egg-positive surveys (Collection rate: 37.02% [2,033/5,492]). Of the participants examined, 13 (0.64%) were found to harbor eggs of 3 parasitic species, Trichuris trichiura, Clonorchis sinensis and Metagonimus yokogawai. Based on the regional distribution, the egg-positive rate in Goseong-gun was 0% (0/550) and that in Hadong-gun was 0.88% (13/1,483). The positive rates for C. sinensis, M. yokogawai, and T. trichiura in Hadong-gun were 0.20% (3/1,483), 0.61% (9/1,483), and 0.07% (1/1,483), respectively. The present survey showed that the prevalence of parasitic infection among students is currently very low even in remote, previously endemic areas, and the present status of parasitic diseases can be summarized as some transmission of fish/food-borne trematodes. Thus, it is necessary to carefully, continuously monitor the trematode infection status, particularly of C. sinensis and M. yokogawai.
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- 2018
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20. Monitoring of Noxious Protozoa for Management of Natural Water Resources
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Tong-Soo Kim, Ho-Joon Shin, Young Yil Bahk, Okjae Rhee, Sangjung Park, Sang-Seob Lee, Pyo Yun Cho, Yun-Kyu Park, Won Hwa Jheong, and Sung Kyu Ahn
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0301 basic medicine ,Veterinary medicine ,Time Factors ,catchment scale investigation ,animal diseases ,Brief Communication ,medicine.disease_cause ,03 medical and health sciences ,Republic of Korea ,parasitic diseases ,medicine ,Animals ,Giardia lamblia ,Naegleria fowleri ,Cryptosporidium parvum ,biology ,Water ,Waterborne diseases ,Giardia ,Cryptosporidium ,030108 mycology & parasitology ,biology.organism_classification ,medicine.disease ,digestive system diseases ,noxious protozoa ,Water resources ,Infectious Diseases ,Water Resources ,Parasitology ,Seasons ,Surface water ,Environmental Monitoring - Abstract
Waterborne parasitic protozoa, particularly Giardia lamblia and Cryptosporidium spp., are common causes of diarrhea and gastroenteritis worldwide. The most frequently identified source of infestation is water, and exposure involves either drinking water or recreation in swimming pools or natural bodies of water. In practice, studies on Cryptosporidium oocysts and Giardia cysts in surface water are challenging owing to the low concentrations of these microorganisms because of dilution. In this study, a 3-year monitoring of Cryptosporidium parvum, Giardia lamblia, and Naegleria fowleri was conducted from August 2014 to June 2016 at 5 surface water sites including 2 lakes, 1 river, and 2 water intake plants. A total of 50 water samples of 40 L were examined. Cryptosporidium oocysts were detected in 22% of samples and Giardia cysts in 32%. Water at the 5 sampling sites was all contaminated with Cryptosporidium oocysts (0–36/L), Giardia cysts (0–39/L), or both. The geometric mean concentrations of Cryptosporidium and Giardia were 1.14 oocysts/L and 4.62 cysts/L, respectively. Thus, effective monitoring plans must take into account the spatial and temporal parameters of contamination because they affect the prevalence and distribution of these protozoan cysts in local water resources.
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- 2018
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21. HSF1 Regulates Mevalonate and Cholesterol Biosynthesis Pathways
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Ji Hong Lim, Hye-Ji Kang, Geon Hee Kim, Ji Hyung Kim, Sang Yeon Kan, Young Yil Bahk, Dong Hoon Shin, and Taerim Oh
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0301 basic medicine ,Cancer Research ,Statin ,medicine.drug_class ,lcsh:RC254-282 ,Article ,Small hairpin RNA ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,simvastatin ,HSF1 ,Transcription factor ,chemistry.chemical_classification ,Reactive oxygen species ,Chemistry ,Cholesterol ,fungi ,Cancer ,cholesterol ,hepatocellular carcinoma ,medicine.disease ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,KRIBB11 ,030104 developmental biology ,heat shock factor 1 ,Oncology ,Simvastatin ,030220 oncology & carcinogenesis ,Cancer research ,medicine.drug - Abstract
Heat shock factor 1 (HSF1) is an essential transcription factor in cellular adaptation to various stresses such as heat, proteotoxic stress, metabolic stress, reactive oxygen species, and heavy metals. HSF1 promotes cancer development and progression, and increased HSF1 levels are frequently observed in multiple types of cancers. Increased activity in the mevalonate and cholesterol biosynthesis pathways, which are very important for cancer growth and progression, is observed in various cancers. However, the functional role of HSF1 in the mevalonate and cholesterol biosynthesis pathways has not yet been investigated. Here, we demonstrated that the activation of RAS-MAPK signaling through the overexpression of H-RasV12 increased HSF1 expression and the cholesterol biosynthesis pathway. In addition, the activation of HSF1 was also found to increase cholesterol biosynthesis. Inversely, the suppression of HSF1 by the pharmacological inhibitor KRIBB11 and short-hairpin RNA (shRNA) reversed H-RasV12-induced cholesterol biosynthesis. From the standpoint of therapeutic applications for hepatocellular carcinoma (HCC) treatment, HSF1 inhibition was shown to sensitize the antiproliferative effects of simvastatin in HCC cells. Overall, our findings demonstrate that HSF1 is a potential target for statin-based HCC treatment.
- Published
- 2019
22. Three-year surveillance of culicine mosquitoes (Diptera: Culicidae) for flavivirus infections in Incheon Metropolitan City and Hwaseong-si of Gyeonggi-do Province, Republic of Korea
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Mun Ju Kwon, Jin-Young Lee, Myung-Deok Kim-Jeon, Hojong Jun, Wook-Gyo Lee, Woojoo Lee, Tong-Soo Kim, Seo Hye Park, Seong Kyu Ahn, Seung Jegal, Jong Yul Roh, Young Yil Bahk, Young Woo Gong, and Kwangsig Joo
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0301 basic medicine ,Veterinary medicine ,Culex ,Veterinary (miscellaneous) ,030231 tropical medicine ,Population ,Mosquito Vectors ,03 medical and health sciences ,0302 clinical medicine ,Republic of Korea ,medicine ,Animals ,Humans ,Flavivirus Infections ,Cities ,education ,Aedes ,education.field_of_study ,biology ,Viral encephalitis ,Flavivirus ,030108 mycology & parasitology ,Japanese encephalitis ,biology.organism_classification ,medicine.disease ,Insect Vectors ,Infectious Diseases ,Culicidae ,Insect Science ,Parasitology ,Female ,Ochlerotatus - Abstract
Japanese encephalitis virus (JEV) is a single stranded positive sense RNA virus of the genus Flavivirus that belongs to family Flaviviridae and emerged as one of the most pivotal form of viral encephalitis. The virus is transmitted to humans by mosquito vector and is an etiological agent of acute zoonotic infection. In this study, we investigated distribution and density over 3-year period in central regions of Korean peninsula. We selected two cities as mosquito-collecting locations and subdivided them into five collection sites; downtown Incheon Metropolitan City as a typical urban area, and the Hwaseong-si area as a rural area. A total of 35,445 female culicine mosquitoes were collected using black light traps or BG Sentinel™ traps from March to November 2016-2018. Aedes (Ae.) vexans nipponii was the most frequently collected specimens (48.91%), followed by Culex (Cx.) pipiens (32.05%), Ochlerotatus (Och.) dorsalis (13.58%), Och. koreicus (1.68%), and Cx. tritaeniorhynchus (1.49%). In the urban area, Cx. pipiens was the predominant species (92.21%) and the other species accounted for
- Published
- 2019
23. Overview of conjugated linoleic acid formation and accumulation in animal products
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Yeonhwa Park, Young Yil Bahk, Sun Jin Hur, and Hyeong Sang Kim
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0301 basic medicine ,030109 nutrition & dietetics ,integumentary system ,General Veterinary ,biology ,Linoleic acid ,Lactococcus ,Propionibacterium ,Conjugated linoleic acid ,0402 animal and dairy science ,food and beverages ,04 agricultural and veterinary sciences ,biology.organism_classification ,040201 dairy & animal science ,Lactic acid ,03 medical and health sciences ,chemistry.chemical_compound ,Rumen ,chemistry ,Biochemistry ,Lactobacillus ,lipids (amino acids, peptides, and proteins) ,Animal Science and Zoology ,Food science ,Bacteria - Abstract
In this review, we provide an overview of the methods used to enhance conjugate linoleic acid (CLA) in animal products and the mechanisms through which CLA is synthesized or accumulated in animal products. Linoleic acid is the key precursor of CLA; thus, CLA can be synthesized through conversion of linoleic acid by ruminal bacteria (Propionibacterium) and lactic acid bacteria (Lactobacillus, Lactococcus, and Streptococcus) with biohydrogenation. Accordingly, it is possible to increase the CLA concentrations in meat, milk, or eggs from animals through feeding of a polyunsaturated fatty acid-rich diet, e.g., a diet containing linoleic acid. Dietary green grass enhances the growth of specific rumen bacteria that are responsible for the synthesis of CLA in animals. CLA or linoleic acid intake increases CLA concentration in dairy products such as milk, cheese, and yogurt. In order to increase CLA status in humans, probiotic bacteria that can be used to convert dietary linoleic acid to CLA. However, it is unclear how much CLA needs to be consumed to have appropriate benefit on human health. Thus, future research is needed to establish methods for controlling the amounts of CLA and CLA isomers in animal products and to determine the exact mechanisms of CLA consumption on human health.
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- 2017
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24. Olfactory receptor Olfr544 responding to azelaic acid regulates glucagon secretion in α-cells of mouse pancreatic islets
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Young Yil Bahk, NaNa Kang, YoonGyu Jae, Min-Soo Kim, NaHye Lee, Cheol Ryong Ku, Youngjoo Byun, Yoon Hee Cho, Eun Jig Lee, and JaeHyung Koo
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medicine.medical_specialty ,Azelaic acid ,Sebacic acid ,Biophysics ,Biology ,Biochemistry ,Glucagon ,Cell Line ,Islets of Langerhans ,Mice ,chemistry.chemical_compound ,Internal medicine ,medicine ,Animals ,Dicarboxylic Acids ,Receptor ,Molecular Biology ,Messenger RNA ,Olfactory receptor ,Pancreatic islets ,Glucagon secretion ,Cell Biology ,Endocrinology ,medicine.anatomical_structure ,chemistry ,medicine.drug - Abstract
Olfactory receptors (ORs) are extensively expressed in olfactory as well as non-olfactory tissues. Although many OR transcripts are expressed in non-olfactory tissues, only a few studies demonstrate the functional role of ORs. Here, we verified that mouse pancreatic α-cells express potential OR-mediated downstream effectors. Moreover, high levels of mRNA for the olfactory receptors Olfr543, Olfr544, Olfr545, and Olfr1349 were expressed in α-cells as assessed using RNA-sequencing, microarray, and quantitative real-time RT-PCR analyses. Treatment with dicarboxylic acids (azelaic acid and sebacic acid) increased intracellular Ca(2+) mobilization in pancreatic α-cells. The azelaic acid-induced Ca(2+) response as well as glucagon secretion was concentration- and time-dependent manner. Olfr544 was expressed in α-cells, and the EC50 value of azelaic acid to Olfr544 was 19.97 μM, whereas Olfr545 did not respond to azelaic acid. Our findings demonstrate that Olfr544 responds to azelaic acid to regulate glucagon secretion through Ca(2+) mobilization in α-cells of the mouse pancreatic islets, suggesting that Olfr544 may be an important therapeutic target for metabolic diseases.
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- 2015
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25. Effect of emulsifiers on microstructural changes and digestion of lipids in instant noodle during in vitro human digestion
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Seung-Jae Lee, C.G. Kim, S.-Y. Lee, Young-Yil Bahk, and Sun Jin Hur
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food.ingredient ,Chemistry ,Thiobarbituric acid ,Starch ,education ,fungi ,Wheat flour ,food and beverages ,Lecithin ,Small intestine ,chemistry.chemical_compound ,medicine.anatomical_structure ,food ,Yolk ,medicine ,TBARS ,lipids (amino acids, peptides, and proteins) ,Food science ,Digestion ,Food Science - Abstract
This study was conducted to investigate the impact of emulsifiers on the digestion of lipid in instant noodles as they passed through a model gastrointestinal (GI) tract. To produce an instant noodle, wheat flour, starch and sodium chloride were mixed with water and then steamed and fried in 990 g of palm oil with 10 g of emulsifiers (T1: soybean lecithin, T2: yolk lecithin, T3: saponin, T4: Tween 20 and T5: caseinate). The largest change in the microstructure of instant noodle occurred when the instant noodle moved from the simulated stomach to the small intestine. Moreover, the value of free fatty acids and thiobarbituric acid reactive substances (TBARS) also significantly increased after small intestine digestion. Various emulsifiers added to stabilize the instant noodle lipids induced different digestion of lipids during in vitro human digestion. The size or amount of instant noodle lipids prepared with yolk lecithin were smaller than those prepared with the other emulsifiers, which suggests that yolk lecithin was more effective at producing small droplets during digestion.
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- 2015
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26. Mouse neutrophils express functional umami taste receptor T1R1/T1R3
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JaeHyung Koo, Ha Young Lee, Yoe-Sik Bae, Young Su Jung, Young Yil Bahk, Jae Sam Hwang, NaHye Lee, NaNa Kang, and Yoo Jung Park
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Lipopolysaccharides ,STAT3 Transcription Factor ,MAPK/ERK pathway ,Umami taste receptor T1R1/T1R3 ,Neutrophils ,Umami ,Biology ,Biochemistry ,Receptors, G-Protein-Coupled ,Mice ,Chemotaxis ,Cytokine ,Inflammation ,Neutrophil ,Umami taste receptorT1R1/T1R3 ,Cell Movement ,Taste receptor ,Serine ,Animals ,Phosphorylation ,Receptor ,Molecular Biology ,Research Articles ,Alanine ,Innate immune system ,Sequence Analysis, RNA ,Tumor Necrosis Factor-alpha ,NF-kappa B ,General Medicine ,Cell biology ,Gene Expression Regulation ,Immunology ,Cytokines ,RNA ,Calcium ,Tumor necrosis factor alpha ,Signal transduction ,Signal Transduction - Abstract
Neutrophils play an important role in the initiation of innate immunity against infection and injury. Although many different types of G-protein coupled receptors are functionally expressed in neutrophils, no reports have demonstrated functional expression of umami taste receptor in these cells. We observed that mouse neutrophils express the umami taste receptor T1R1/T1R3 through RNA sequencing and quantitative RT-PCR analysis. Stimulation of mouse neutrophils with L-alanine or L-serine, which are ligands for the umami taste receptor, elicited not only ERK or p38 MAPK phosphorylation but also chemotactic migration. Moreover, addition of L-alanine or L-serine markedly reduced the production of several cytokines including TNF-α induced by lipopolysaccharide (LPS) through inhibition of NF-κB activity or STAT3 phosphorylation in neutrophils. Our findings demonstrate that neutrophils express the umami taste receptor, through which tastants stimulate neutrophils, resulting in chemotactic migration, and attenuation of LPS-induced inflammatory response. [BMB Reports 2014; 47(11): 649-654]
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- 2014
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27. A study of substrate specificity for a CTD phosphatase, SCP1, by proteomic screening of binding partners
- Author
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Young Yil Bahk and Young Jun Kim
- Subjects
Proteomics ,Molecular Sequence Data ,Phosphatase ,Biophysics ,Cell Cycle Proteins ,RNA polymerase II ,Biochemistry ,Interactome ,Substrate Specificity ,law.invention ,Dephosphorylation ,Mice ,law ,Protein Interaction Mapping ,Phosphoprotein Phosphatases ,Animals ,Humans ,Amino Acid Sequence ,Phosphorylation ,Molecular Biology ,biology ,fungi ,HEK 293 cells ,Nuclear Proteins ,Cell Biology ,Kinetics ,HEK293 Cells ,NIH 3T3 Cells ,biology.protein ,Recombinant DNA ,CTD - Abstract
RNA polymerase II carboxyl-terminal domain (RNAPII CTD) phosphatases are a newly emerging family of phosphatases. Recently a CTD-specific phosphatase, small CTD phosphatase 1 (SCP1), has shown to act as an evolutionarily conserved transcriptional corepressor for inhibiting neuronal gene transcription in non-neuronal cells. In this study, using the established NIH/3T3 and HEK293T cells, which are expressing human SCP1 proteins under the tight control of expression by doxycycline, a proteomic screening was conducted to identify the binding partners for SCP1. Although the present findings provide the possibility for new avenues to provide to a better understanding of cellular physiology of SCP1, now these proteomic and some immunological approaches for SCP1 interactome might not represent the accurate physiological relevance in vivo. In this presentation, we focus the substrate specificity to delineate an appearance of the dephosphorylation reaction catalyzed by SCP1 phosphatase. We compared the phosphorylated sequences of the immunologically confirmed binding partners with SCP1 searched in HPRD. We found the similar sequences from CdcA3 and validated the efficiency of enzymatic catalysis for synthetic phosphopeptides the recombinant SCP1. This approach led to the identification of several interacting partners with SCP1. We suggest that CdcA3 could be an enzymatic substrate for SCP1 and that SCP1 might have the relationship with cell cycle regulation through enzymatic activity against CdcA3.
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- 2014
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28. In Vitro Analysis of the Anti-Cancer Activity of Mitoxantrone Loaded on Magnetic Nanoparticles
- Author
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Jeung Hee An, Jae-Soo Shin, Young Yil Bahk, Dong-Hee Kim, Woo-Yoon Park, Kang-Hyun Chung, Je-Ran Chun, and Kwon-Jai Lee
- Subjects
Mitoxantrone ,Chemistry ,Cell growth ,Biomedical Engineering ,Pharmaceutical Science ,Medicine (miscellaneous) ,Cancer ,Bioengineering ,Caspase 3 ,urologic and male genital diseases ,medicine.disease ,DU145 ,Apoptosis ,Drug delivery ,medicine ,Cancer research ,Cytotoxic T cell ,General Materials Science ,medicine.drug - Abstract
In this study, the anti-tumor activity of mitoxantrone loaded on magnetic nanoparticles (MTMP) was examined using DU145 prostate cancer cells. Composite nanoparticles with an average size of 20 nm were prepared using a chemical co-precipitation technique. The MTMP nanoparticles were cytotoxic to DU145 cells and inhibited cell proliferation. The expression levels of apoptosis related proteins in DU145 cells, including PARP and caspase 3, were increased after MTMP treatment. In this study, the therapeutic potential of MTMP in targeted-therapy against prostate cancer was demonstrated and MTMP was more effective when coupled to drug delivery vehicle than pure mitoxantrone.
- Published
- 2013
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29. Expression and Purification of Human Farnesoid X Receptor-Ligand Binding Domain as Soluble Form Using a Dual Cistronic Expression Vector
- Author
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Hyun Kang, Young Yil Bahk, and Micheal B Ye
- Subjects
Expression vector ,Genetic Vectors ,Gene Expression ,Receptors, Cytoplasmic and Nuclear ,Biological activity ,Promoter ,General Medicine ,Biology ,Applied Microbiology and Biotechnology ,Recombinant Proteins ,Protein Structure, Tertiary ,law.invention ,Genes ,Biochemistry ,Nuclear receptor ,law ,Escherichia coli ,Recombinant DNA ,Humans ,Farnesoid X receptor ,Vector (molecular biology) ,hormones, hormone substitutes, and hormone antagonists ,Fluorescence anisotropy ,Protein Binding ,Biotechnology - Abstract
In this study, we show the expression and purification of the human recombinant farnesoid X receptor (FXR)- ligand binding domain (LBD) protein in E. coli using a double cistronic vector, pACYCDuet-1, as a soluble form. We describe here the expression and characterization of a biologically active FXR-LBD(248-476). When expressed in the influence of bacterial promoters (P(T7) and P(Tac)) of the single cistronic expression vectors, the human recombinant FXR-LBD(248-476) was found to be totally insoluble. However, by using a double cistronic expression vector, we were able to obtain the human recombinant FXR-LBD(248-476) in a soluble form. To allow for biological activities, we have subcloned into the pACYCDuet-1 vector, expressed in E. coli cells at some optimized conditions, and purified and characterized the human recombinant active FXR-LBD(248-476) proteins using the fluorescence polarization assay. This suggests that the expression of FXR-LBD in a double cistronic vector improves its solubility and probably assists its correct folding for the biologically active form of the proteins. We suggest that this may represent a new approach to high expression of other nuclear receptors and may be useful as well for other classes of heterodimeric protein partners.
- Published
- 2013
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30. A novel bioactive peptide derived from enzymatic hydrolysis of Ruditapes philippinarum: Purification and investigation of its free-radical quenching potential
- Author
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Hyuk Jung Kweon, Young Yil Bahk, Jin-Woo Hwang, Chang-Bum Ahn, Sang-Ho Moon, Byong-Tae Jeon, You-Jin Jeon, Yon-Suk Kim, Eun-Kyung Kim, and Pyo-Jam Park
- Subjects
chemistry.chemical_classification ,Chromatography ,Quenching (fluorescence) ,Antioxidant ,DPPH ,medicine.medical_treatment ,Bioengineering ,Peptide ,Applied Microbiology and Biotechnology ,Biochemistry ,Hydrolysate ,chemistry.chemical_compound ,chemistry ,Enzymatic hydrolysis ,medicine ,Organic chemistry ,Hydroxyl radical ,Alkyl - Abstract
We purified a novel antioxidant peptide from Ruditapes philippinarum ( R. philippinarum ) and investigated its free radical scavenging activities. To prepare the peptide, eight proteases were tested for enzymatic hydrolysis. α-chymotrypsin hydrolysate, which showed clearly superior hydroxyl radical scavenging activity ( p R. philippinarum effectively scavenged hydroxyl, DPPH, alkyl and superoxide radicals, with observed IC 50 values of 0.042, 0.091, 0.107 and 0.372 mg/ml, respectively. This is the first report of an antioxidant peptide derived from the hydrolysates of R. philippinarum which, further, possesses competitive free radical quenching potential.
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- 2013
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31. Clonorchis sinensis excretory-secretory products promote the migration and invasion of cholangiocarcinoma cells by activating the integrin β4-FAK/Src signaling pathway
- Author
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Jhang Ho Pak, In Ki Kim, Sejung Maeng, Tong-Soo Kim, Qudsia Bashir, Sung-Jong Hong, and Young Yil Bahk
- Subjects
0301 basic medicine ,Real-Time Polymerase Chain Reaction ,Extracellular matrix ,Focal adhesion ,03 medical and health sciences ,Cell Movement ,Cell Line, Tumor ,parasitic diseases ,Animals ,Humans ,Molecular Biology ,Paxillin ,Clonorchis sinensis ,biology ,Cell adhesion molecule ,Gene Expression Profiling ,Integrin beta4 ,Cell migration ,Helminth Proteins ,Vinculin ,Cell biology ,Up-Regulation ,030104 developmental biology ,src-Family Kinases ,Focal Adhesion Kinase 1 ,Immunology ,biology.protein ,Parasitology ,Signal transduction ,Proto-oncogene tyrosine-protein kinase Src ,Signal Transduction - Abstract
Cholangiocarcinoma (CCA) is a slow-growing but highly metastatic cancer. Its metastatic potential largely explains its high mortality rate. A recognized risk factor for CCA development is infection with the liver flukes Opisthorchis viverrini and Clonorchis sinensis. We previously reported that the excretory-secretory products (ESPs) of C. sinensis promoted the three-dimensional aggregation and invasion of CCA cells. In the present study, a quantitative real-time PCR array of extracellular matrix (ECM) and adhesion molecules was used to examine the regulatory mechanism of ESP-mediated CCA cell migration and invasion. In particular, the expression levels of integrin α isoforms and β4 were upregulated in response to ESPs. Increased expression of integrin β4 was probably correlated with activation of focal adhesion kinase (FAK) and the steroid receptor coactivator (Src) family kinase and the subsequent activation of two downstream focal adhesion molecules, paxillin and vinculin. Moreover, inhibition of FAK/Src activation reduced paxillin and vinculin phosphorylation and attenuated ESP-induced CCA cell migration and invasion. These findings suggest that the integrin β4-FAK/Src signaling axis may play a crucial role in clonorchiasis-associated CCA metastasis during tumor progression.
- Published
- 2016
32. Clonorchis sinensis, an oriental liver fluke, as a human biological agent of cholangiocarcinoma: a brief review
- Author
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Young Yil Bahk, Tong-Soo Kim, Jhang Ho Pak, and Jong-Bo Kim
- Subjects
0301 basic medicine ,DNA Repair ,030231 tropical medicine ,Population ,Zoology ,Disease ,medicine.disease_cause ,Biochemistry ,Cholangiocarcinoma ,03 medical and health sciences ,0302 clinical medicine ,Infestation ,parasitic diseases ,medicine ,Animals ,Humans ,Opisthorchis viverrini ,education ,Molecular Biology ,Schistosoma haematobium ,education.field_of_study ,Clonorchis sinensis ,Arachidonate 5-Lipoxygenase ,biology ,General Medicine ,Liver fluke ,biology.organism_classification ,medicine.disease ,Invited Mini Review ,030104 developmental biology ,Bile Duct Neoplasms ,Cyclooxygenase 2 ,Liver flukes ,Clonorchiasis ,Reactive Oxygen Species ,Liver cancer ,DNA Damage - Abstract
Parasitic diseases remain an unarguable public health problem worldwide. Liver fluke Clonorchis sinensis is a high risk pathogenic parasitic helminth which is endemic predominantly in Asian countries, including Korea, China, Taiwan, Vietnam, and the far eastern parts of Russia, and is still actively transmitted. According to the earlier 8th National Survey on the Prevalence of Intestinal Parasitic Infections in 2012, C. sinensis was revealed as the parasite with highest prevalence of 1.86% in general population among all parasite species surveyed in Korea. This fluke is now classified under one of the definite Group 1 human biological agents (carcinogens) by International Agency of Research on Cancer (IARC) along with two other parasites, Opisthorchis viverrini and Schistosoma haematobium. C. sinensis infestation is mainly linked to liver and biliary disorders, especially cholangiocarcinoma (CCA). For the purposes of this mini-review, we will only focus on C. sinensis and review pathogenesis and carcinogenesis of clonorchiasis, disease condition by C. sinensis infestation, and association between C. sinensis infestation and CCA. In this presentation, we briefly consider the current scientific status for progression of CCA by heavy C. sinensis infestation from the food-borne trematode and development of CCA. [BMB Reports 2016; 49(11): 590-597].
- Published
- 2016
33. Transgenic expression of non-structural genes of Theiler's virus suppresses initial viral replication and pathogenesis of demyelination
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Hyun Seok Kang, Byung S. Kim, Eui Young So, Jinjong Myoung, and Young Yil Bahk
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0301 basic medicine ,Gene Expression Regulation, Viral ,Viral pathogenesis ,viruses ,T-Lymphocytes ,Immunology ,T cells ,Mice, Transgenic ,TMEV ,Pathogenesis ,Biology ,P2/P3 transgenic mice ,Virus Replication ,Virus ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Mice ,0302 clinical medicine ,Theilovirus ,Demyelinating disease ,medicine ,Animals ,Cells, Cultured ,General Neuroscience ,Research ,medicine.disease ,Virology ,3. Good health ,Mice, Inbred C57BL ,Chronic infection ,030104 developmental biology ,Neurology ,Viral replication ,Female ,CNS ,Viral load ,030217 neurology & neurosurgery ,Demyelinating Diseases - Abstract
Background Chronic infection with Theiler’s murine encephalomyelitis virus (TMEV) in susceptible SJL/J mice induces an immune-mediated demyelinating disease and has extensively been used as a relevant infectious model for multiple sclerosis (MS). Infection of the host with many other viruses also leads to acute or chronic inflammatory diseases in the central nervous system (CNS). Levels of viral load in the host often play a critical role in the pathogenesis of virus-induced diseases. Thus, the inhibition of viral replication in the host against a broad spectrum of similar viruses is critically important for preventing the viral pathogenicity. Methods P2/P3-expressing transgenic (B6 X SJL)F1 founders were generated and bred onto the C57BL/6 and SJL/J backgrounds. Differences in the development of demyelinating disease were compared. Viral persistence, cytokine production, and immune responses in the CNS of infected control and P2/P3-Tg mice were analyzed after infection using quantitative PCR, ELISA, and flow cytometry. Various cell types from the control and P2/P3-Tg mice, as well as cells transfected in vitro with the P2 and/or P3 regions, were also analyzed for viral replication and innate cytokine production. Results P2/P3-transgenic (P2/P3-Tg) mice carrying the viral non-structural protein genes displayed significantly reduced virus-specific T cell responses in the CNS against both the structural and non-structural proteins. Consequently, viral loads in the CNS were greater in the Tg mice during the chronic infection. However, P2/P3-Tg SJL mice exhibited reduced disease incidence and less severe clinical symptoms than did their non-transgenic littermates. Interestingly, P2/P3-Tg mice showed low viral loads in the CNS at a very early period after infection (1–3 days) with TMEV and related EMCV but not unrelated VSV. Cells from P2/P3-Tg mice and cells transfected with the P2 and/or P3 regions in vitro yielded also lower viral replication but higher IFN-α/β production. Conclusions This study demonstrates that the expression of viral non-structural genes in mice inhibits initial viral replication and suppresses sustaining pathogenic anti-viral immune responses to broad viral determinants. It appears that the elevation of innate immune cytokines produced in the cells expressing the non-structural viral genes upon viral infection is responsible for the inhibitions. The inhibition is partially virus-specific as it is more efficient for a related virus compared to an unrelated virus, suggesting a role for the similarity in the viral genome structures. Therefore, the expression of viral non-structural genes may serve as a useful new method to prevent a broadly virus-specific pathogenesis in the hosts.
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- 2016
34. Comparative biochemical and functional properties of two leucine aminopeptidases of Clonorchis sinensis
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Sung-Jong Hong, Hye-Lim Ju, Jung-Mi Kang, Young-Yil Bahk, Jung-Won Ju, Woon-Mok Sohn, Tong-Soo Kim, and Byoung-Kuk Na
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Transcription, Genetic ,Genes, Protozoan ,Cyprinidae ,Antibodies, Protozoan ,Sequence alignment ,Substrate Specificity ,Rats, Sprague-Dawley ,Leucyl Aminopeptidase ,Structure-Activity Relationship ,Leucine ,Catalytic Domain ,Enzyme Stability ,Animals ,Humans ,Metacercariae ,Amino Acid Sequence ,Cloning, Molecular ,Enzyme Inhibitors ,Intestinal Mucosa ,Molecular Biology ,Peptide sequence ,Metalloexopeptidase ,chemistry.chemical_classification ,Clonorchis sinensis ,biology ,Gastrodermis ,Helminth Proteins ,Hydrogen-Ion Concentration ,biology.organism_classification ,Molecular biology ,Recombinant Proteins ,Rats ,Amino acid ,Enzyme ,Biochemistry ,chemistry ,Clonorchiasis ,Parasitology ,Sequence Alignment - Abstract
Leucine aminopeptidases (LAP; EC 3.4.11.1) are a group of metalloexopeptidases, which catalyze the sequential removal of leucine amino acids from the N-termini of the polypeptides or proteins. In this study, we identified two novel genes that encode LAPs of Clonorchis sinensis (CsLAP1 and CsLAP2) and characterized their biochemical and functional properties. Multiple sequence alignment of the deduced amino acid sequences of CsLAP1 and CsLAP2 with those of other organisms revealed that typical metal-binding coordinating and active site residues for LAPs were well conserved in CsLAP1 and CsLAP2. Recombinant CsLAP1 and CsLAP2 showed similar biochemical properties such as pH optima at pH 8.0 and stability at neutral pHs. Both enzymes were specifically inhibited by bestatin and showed preferential substrate specificity for Leu-MCA. However, the enzymes differed in that they required different metal ions for maximum activity. Expressions of CsLAP1 and CsLAP2 were detected throughout the various developmental stages of C. sinensis, and their transcription levels increased gradually in accordance with the maturation of the parasite. Both enzymes were identified in soluble worm extract of C. sinensis, but not in excretory and secretory products. Immunolocalization studies showed that both enzymes were co-localized to the intestinal epithelial cells and gastrodermis of the parasite. These results collectively suggest that CsLAP1 and CsLAP2 are synthesized in the intestinal epithelial and gastrodermal cells of C. sinensis and may be involved in the final digestion of peptides that hydrolyzed within intestinal lumen followed by absorbed into gastrodermal cells of the parasite.
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- 2012
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35. Transgenic overexpression of p23 induces spontaneous hydronephrosis in mice
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Jung Ah Moon, Hye Jin Kim, Young Yil Bahk, Jong Eun Lee, Seungyeon Kim, Han Woong Lee, Young Hoon Sung, Jae-Hoon Lee, Na Young Ha, Tae Hyun Yoo, Jae Il Roh, and In Jeoung Baek
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congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,biology ,Transgene ,CYP1B1 ,Kidney metabolism ,Cell Biology ,Aryl hydrocarbon receptor ,Molecular biology ,Pathology and Forensic Medicine ,Endocrinology ,Downregulation and upregulation ,In vivo ,Heat shock protein ,Internal medicine ,biology.protein ,medicine ,skin and connective tissue diseases ,Receptor ,Molecular Biology - Abstract
p23 is a cochaperone of heat shock protein 90 and also interacts functionally with numerous steroid receptors and kinases. However, the in vivo roles of p23 remain unclear. To explore its in vivo function, we generated the transgenic (TG) mice ubiquitously overexpressing p23. The p23 TG mice spontaneously developed kidney abnormalities closely resembling human hydronephrosis. Consistently, kidney functions deteriorate significantly in the p23 TG mice compared to their wild-type (WT) littermates. Furthermore, the expression of target genes for aryl hydrocarbon receptor (AhR), such as cytochrome P450, family 1, subfamily A, polypeptide 1 (Cyp1A1) and cytochrome P450, family 1, subfamily B, polypeptide 1 (Cyp1B1), were induced in the kidneys of the p23 TG mice. These results indicate that the overexpression of p23 contributes to the development of hydronephrosis through the upregulation of the AhR pathway in vivo.
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- 2011
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36. An Analysis of an Interactome for Apoptosis Factor, Ei24/PIG8, Using the Inducible Expression System and Shotgun Proteomics
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Young Yil Bahk, Jae Hoon Lee, Han-Woong Lee, and Ick Hyun Cho
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Proteomics ,Immunoprecipitation ,Green Fluorescent Proteins ,Immunoblotting ,Cell ,Fluorescent Antibody Technique ,Apoptosis ,Biology ,Biochemistry ,Interactome ,Mice ,Cell Line, Tumor ,Gene expression ,medicine ,Animals ,Shotgun proteomics ,Gene ,Microscopy, Confocal ,Cell growth ,Nuclear Proteins ,General Chemistry ,Molecular biology ,Cell biology ,medicine.anatomical_structure ,Gene Expression Regulation ,Cell culture ,Doxycycline ,NIH 3T3 Cells ,Apoptosis Regulatory Proteins ,Carrier Proteins ,Protein Binding - Abstract
ei24 (etoposide-induced 2.4 kb transcript, also designated PIG8 (p53-induced gene 8)), is a DNA damage response gene involved in growth suppression and apoptosis. ei24 gene expression is specifically induced by wild type p53, and its overexpression suppresses cell growth by inducing apoptotic cell death. Generally, the protein-protein interaction is known to regulate their targets, as well as to modify cell fates. In this study, using the established NIH/3T3, oncogenic H-Ras/G12V transformed NIH/3T3, and B16F10 cells, which are expressing mouse Ei24 proteins under the tight control of expression by doxycycline, a proteomic screening was conducted to identify the binding partners for Ei24. Immunoprecipitation of mEi24 and associated proteins was performed using the mEi24 expressing cell lysates. Isolated immuno-complexes were resolved by SDS-PAGE and analyzed by liquid chromatography tandem mass spectrometry. There were 61 novel potential mEi24 interacting proteins identified, among which are NIH/3T3/mEi24, H-Ras/G12V/NIH/3T3/mEi24, and B16F10/mEi24 cells; however, some mEi24 interacting proteins were specific to two NIH/3T3 related cells and to B16F10/mEi24 cells. This approach led to the identification of many interacting partners, and the discovery of these associated proteins will lead to a better understanding of the mechanisms underlying the physiological and cell biological roles of Ei24.
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- 2010
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37. Caenorhabditis elegans mitofilin homologs control the morphology of mitochondrial cristae and influence reproduction and physiology
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Ji Hui Kim, Sung Sik Han, Hyeon Sook Koo, Ji Young Mun, Tae Hoon Lee, Bum Ho Yoo, and Young Yil Bahk
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biology ,ATP synthase ,MICOS complex ,Physiology ,Immunoelectron microscopy ,Clinical Biochemistry ,Cell Biology ,Mitochondrion ,biology.organism_classification ,Mitochondria ,Cell biology ,Mitochondrial Proteins ,Crista ,Mutation ,biology.protein ,Animals ,Humans ,Protein Isoforms ,Caenorhabditis elegans ,Caenorhabditis elegans Proteins ,Reactive Oxygen Species ,Inner mitochondrial membrane ,Cristae formation - Abstract
Human mitofilin is a mitochondrial protein that controls cristae formation. Here, we investigated the role of the Caenorhabditis elegans mitofilin homologs, IMMT-1 and -2, in reproduction, physiology, and mitochondrial cristae formation. Mutation of either immt-1 or immt-2 produced defects in germline development and egg-laying. These defects were exacerbated by the double mutation, which greatly reduced motility, increased levels of reactive oxygen species, decreased mitochondrial mass, and imparted resistance to oxidative stress. Cryo-electron microscopy and electron tomography revealed that each of the single mutations resulted in curved and stacked mitochondrial crista tubules as well as a reduced number of crista junctions. The immt-2 mutation was also associated with the presence of outer mitochondrial membrane pores, which were larger in the double mutant. IMMT-1 and IMMT-2 proteins were localized to the inner mitochondrial membrane, as seen by immunoelectron microscopy, and they behaved as oligomers or large complexes with F(1)F(0) ATP synthase in native polyacrylamide gel electrophoresis. These findings suggest that the two C. elegans mitofilin isoforms have non-overlapping functions in controlling mitochondrial cristae formation.
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- 2010
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38. A family of cathepsin F cysteine proteases of Clonorchis sinensis is the major secreted proteins that are expressed in the intestine of the parasite
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Young-Yil Bahk, Jung-Mi Kang, Tong-Soo Kim, Pyo-Yun Cho, Sung-Jong Hong, Byoung-Kuk Na, and Woon-Mok Sohn
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Proteases ,Cathepsin F ,Molecular Sequence Data ,Gene Expression ,Animals ,Parasite hosting ,Amino Acid Sequence ,Cloning, Molecular ,Intestinal Mucosa ,Molecular Biology ,Phylogeny ,Cathepsin ,chemistry.chemical_classification ,Clonorchis sinensis ,biology ,Helminth Proteins ,biology.organism_classification ,Cysteine protease ,Intestines ,Protein Transport ,Secretory protein ,Enzyme ,Biochemistry ,chemistry ,Multigene Family ,Parasitology ,Extracellular Space ,Sequence Alignment - Abstract
Cysteine proteases of helminth parasites play essential roles in parasite physiology as well as in a variety of important pathobiological processes. In this study, we identified a multigene family of cathepsin F cysteine proteases in Clonorchis sinensis (CsCFs). We identified a total of 12 CsCF genes through cDNA cloning using degenerate PCR primers followed by RACE. Sequence and phylogenetic analysis of the genes suggested they belonged to the cathepsin F-like enzyme family and further clustered into three different subfamilies. Enzymatic and proteomic analysis of C. sinensis excretory and secretory products (ESP) revealed that multiple isoforms of CsCF were the major proteins present in the ESP and the proteolytic activity of the ESP is mainly attributable to the enzymes. Comparative analysis of representative enzymes for each subfamily, CsCF-4, CsCF-6, and CsCF-11, showed that they share similar biochemical properties typical for cathepsin F-like enzymes, but significant differences were also identified. The enzymes were expressed throughout various developmental stages of the parasite and the transcripts increased gradually in accordance with the maturation of the parasite. Immunolocalization analysis of CsCFs showed that they were mainly localized in the intestine and intestinal contents of the parasite. These results collectively suggested that CsCFs, which are apparently synthesized in the epithelial cells lining the parasite intestine and secreted into the intestinal lumen of the parasite, might have a cooperative role for nutrient uptake in the parasite. Furthermore, they were eventually secreted into outside of the parasite and may perform additional functions for host-parasite interactions.
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- 2010
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39. A Cross-talk between oncogenic Ras and tumor suppressor PTEN through FAK Tyr861 phosphorylation in NIH/3T3 mouse embryonic fibroblasts
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Young Yil Bahk, Ick-Hyun Cho, and Tong-Soo Kim
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MAPK/ERK pathway ,Biophysics ,Biochemistry ,3T3 cells ,Mice ,medicine ,Animals ,PTEN ,Phosphorylation ,Molecular Biology ,Oncogene ,biology ,Chemistry ,Kinase ,PTEN Phosphohydrolase ,Cell Biology ,Fibroblasts ,Cell biology ,medicine.anatomical_structure ,Cell culture ,Focal Adhesion Kinase 1 ,Mutation ,NIH 3T3 Cells ,ras Proteins ,Cancer research ,biology.protein ,Tyrosine ,Signal transduction - Abstract
Although Ras is a potent oncogene, its tumorigenicity depends on cellular context and cooperative events. Tumor suppressor PTEN is the most important negative regulator of the cell-survival signaling pathway initiated by phosphoinositide 3-OH kinase. Previously, we established various NIH/3T3 cells expressing H-Ras mutant proteins. This report shows that expression of PTEN is suppressed by the oncogenic H-Ras at its protein and transcript levels as well as by oncogenic K- and N-Ras. This activity of oncogenic Ras is mediated by Raf-1/Erk/MEK signaling pathway. In our previous reports, FAK Y(861) phosphorylation is higher in H-Ras transformed NIH/3T3 cells. In this report, level of FAK pY(861) was examined in Ras mutant cell lines. By generating wild-type PTEN, lipid phosphatase-deficient PTEN and activity-inert PTEN-inducible cell lines in the background of oncogenic H-Ras stable expression in NIH/3T3 cells, we show level of FAK pY(861) is decreased by protein phosphatase activity of PTEN.
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- 2008
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40. Proteomic analysis of androgen-independent growth in low and high passage human LNCaP prostatic adenocarcinoma cells
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Young Yil Bahk, Tag Keun Yoo, Seyoon Kim, and Yun-Hee Youm
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Cell Extracts ,Male ,Proteomics ,medicine.medical_specialty ,Small interfering RNA ,Proteome ,Adenocarcinoma ,Biology ,urologic and male genital diseases ,Biochemistry ,Prostate cancer ,Cell Line, Tumor ,Cell Clone ,Internal medicine ,LNCaP ,medicine ,Humans ,Gene silencing ,Electrophoresis, Gel, Two-Dimensional ,Gene Silencing ,RNA, Messenger ,RNA, Small Interfering ,Molecular Biology ,Cell Proliferation ,Doxazosin ,Prostatic Neoplasms ,General Medicine ,medicine.disease ,Phenotype ,Clone Cells ,Neoplasm Proteins ,Gene Expression Regulation, Neoplastic ,Androgen receptor ,Endocrinology ,Receptors, Androgen ,Androgens ,Cancer research - Abstract
The present study compared the proteomic characteristics of a low passage number (L-33) and high passage number (H-81) LNCaP cell clone. Marked differences in protein expression were noted in the response of L-33 and H-81 cells to androgens. To investigate if regulation of these proteins was androgen-dependent, expression of the androgen receptor was silenced via small interfering RNA. Consistent with the proteomic data, abrogation of androgen receptor production in H-81 cells resulted in the reversed expression level into L-33 cells compared with non-treated H-81 LNCaP cells. The results clarify the progression into an androgen-independent phenotype.
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- 2008
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41. Diagnosis of vivax malaria using an IgM capture ELISA is a sensitive method, even for low levels of parasitemia
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Seung Bum Yoo, Jae Hoon Oh, Young-Ha Lee, Kook Jin Lim, Joon Sup Yeom, Jae-Won Park, Yu Sam Kim, and Young Yil Bahk
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Antibodies, Protozoan ,Antigens, Protozoan ,Enzyme-Linked Immunosorbent Assay ,Parasitemia ,Sensitivity and Specificity ,Medical microbiology ,parasitic diseases ,Malaria, Vivax ,medicine ,Animals ,Humans ,Merozoite surface protein ,Child ,Merozoite Surface Protein 1 ,Aged ,Aged, 80 and over ,General Veterinary ,biology ,Blood Screening ,General Medicine ,Middle Aged ,medicine.disease ,Virology ,Diagnosis of malaria ,Titer ,Infectious Diseases ,Immunoglobulin M ,Insect Science ,Immunology ,biology.protein ,Female ,Parasitology ,Antibody ,Plasmodium vivax ,Malaria - Abstract
Although diagnosis of Plasmodium vivax malaria has been difficult when it is present at a low parasite density, it was recently revealed that an antibody assay was a good method of screening for malaria in blood banks. However, the use of this method for the diagnosis of malaria is limited due to the persistence of specific immunoglobulin (Ig) G. Therefore, we evaluated specific IgM antibody responses against the C-terminal region of the merozoite surface protein 1 of P. vivax (PvMSP1c) in sera obtained from patients with vivax malaria using various assays. The IgM capture enzyme-linked immunosorbent assay showed good sensitivity (97.7%; 308/315) and specificity (99.1%, 446/450). In addition, the results of this assay were not related to parasite density, and a high reactivity was observed when there was a low level of parasitemia. Furthermore, we found that patients with cases of malaria that had relapsed still had the IgM titers against PvMSP1c. Therefore, the use of IgM ELISA for the detection of specific IgM that was not involved in memorial immune activity could be an alternative tool for the diagnosis of malaria and blood screening, even in areas in which malaria is endemic.
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- 2008
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42. A differentially expressed proteomic analysis in placental tissues in relation to pungency during the pepper fruit development
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Seyoon Kim, Min Rae Cho, Young Yil Bahk, Je Min Lee, Eun Young Yoo, Byung-Dong Kim, Myeong Cheoul Cho, and Ji Young Lee
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Pungency ,Proteome ,Molecular Sequence Data ,food and beverages ,Context (language use) ,Biology ,Trypsin ,Proteomics ,Biochemistry ,Staining ,Fruit ,Pepper ,Botany ,medicine ,Electrophoresis, Gel, Two-Dimensional ,Amino Acid Sequence ,Capsaicin ,Volatilization ,Capsicum ,Molecular Biology ,Peptide sequence ,Plant Proteins ,medicine.drug - Abstract
Using proteomic analysis including 2-DE, image analysis, and protein identification with LC-MS/MS, an investigation aimed at a better understanding of the differentially expressed proteins and/or gene products was carried out with total cell extracts from placental tissues in nonpungent (Capsicum annuum cv. Saeng-Ryeog #213) and pungent peppers (C. annuum cv. Saeng-Ryeog #211). Mobilization of the most abundant proteins, which were on the gels of pH ranges of 4-7, 4.5-5.5, 5.5-6.7, and 6-9, and showed very similar profiles in the two tissues, revealing approximately 2600 protein spots consisting of 1200 on pH 4-7, 600 on 4.5-5.5, 550 on 5.5-6.7, 250 on 6-9. Of these, 37 protein spots, which appeared in only pungent tissues but not in nonpungent tissues or markedly increased in their staining intensities on the gels from pungent tissue, were selected, excised, in-gel trypsin digested, and analyzed by LC-ESI-MS/MS. Peptide MS/MS data were searched against publicly available protein and EST databases, and 22 proteins were identified. Based on this result, we tested and compared the differential expression during fruit development on the 2-DE gels with total cell extracts from placental tissues of pungent and nonpungent peppers at an interval of 10 days from 10 to 40 days after flowering. In addition, this differential protein expression was further confirmed for some subsets of candidates by Northern-blot analysis with RNA samples from placental tissues harvested from each pepper fruit at the same sampling intervals. In this study, the physiological implications, revealed from the experimental data in the levels of proteome and transcripts, are discussed in the context of a complex biosynthesis network of capsaicinoids in pepper cells responsive to pungency.
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- 2006
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43. Suppression of Egr-1 transcription through targeting of the serum response factor by oncogenic H-Ras
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Bonghee Lee, Il-Yup Chung, Julian Downward, Young Seek Lee, Hermann Eibel, Prem M. Sharma, Soon Young Shin, Young Yil Bahk, Jerrold M. Olefsky, Young Ho Kim, Young Han Lee, and Jesang Ko
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Transcriptional Activation ,Serum Response Factor ,Transcription, Genetic ,Class I Phosphatidylinositol 3-Kinases ,Down-Regulation ,Article ,General Biochemistry, Genetics and Molecular Biology ,Mice ,Phosphatidylinositol 3-Kinases ,Gene expression ,Serum response factor ,Animals ,Promoter Regions, Genetic ,Molecular Biology ,Transcription factor ,Cells, Cultured ,PI3K/AKT/mTOR pathway ,Early Growth Response Protein 1 ,Platelet-Derived Growth Factor ,Regulation of gene expression ,Phosphoinositide 3-kinase ,General Immunology and Microbiology ,biology ,General Neuroscience ,3T3 Cells ,Fibroblasts ,Serum Response Element ,body regions ,Genes, ras ,Gene Expression Regulation ,biology.protein ,Cancer research ,Mitogen-Activated Protein Kinases ,Signal transduction ,hormones, hormone substitutes, and hormone antagonists ,Signal Transduction - Abstract
The transcription factor Egr-1 functions as a key regulator in cellular growth, differentiation, and apoptosis. The loss of Egr-1 expression is closely associated with tumor development, although the molecular mechanism behind the suppression of Egr-1 is largely unknown. In this report, we show that growth factor-induced transcriptional activation of Egr-1 gene is downregulated by chronic expression of oncogenic H-Ras in NIH3T3 fibroblasts. Our results demonstrate that phosphoinositide 3-kinase (PI3K) signaling is necessary for oncogenic H-Ras-mediated reduction of Egr-1 gene expression. Aberrant activation of PI3K signaling by oncogenic Ras decreased the level of serum response factor (SRF) protein through the acceleration of proteolysis, which resulted in decreased SRF binding to the serum response element (SRE) sites within the Egr-1 promoter, leading to the suppression of Egr-1 transcription. Inhibition of PI3K signaling restored the downregulation of SRF and Egr-1 expression caused by oncogenic Ras. Our findings suggest a novel signaling mechanism by which prolonged activation of oncogenic H-Ras can trigger the loss of tumor suppressor Egr-1 through the PI3K pathway in NIH3T3 fibroblast model cell lines.
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- 2006
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44. A proteomic analysis during serial subculture and osteogenic differentiation of human mesenchymal stem cell
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Hyun Jin Sun, Yon Rak Choi, Jung Hye Shim, Seung Hwan Han, Young Yil Bahk, and Jin Woo Lee
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Adult ,Male ,Proteomics ,Adolescent ,Chaperonins ,Proteome ,Cell Culture Techniques ,Down-Regulation ,Bone Marrow Cells ,Biology ,Downregulation and upregulation ,Chloride Channels ,Osteogenesis ,Annexin ,Humans ,Orthopedics and Sports Medicine ,RNA, Messenger ,YWHAG ,Cells, Cultured ,Heat-Shock Proteins ,Cell Proliferation ,Histocytochemistry ,Cell growth ,Mesenchymal stem cell ,Cell Differentiation ,Mesenchymal Stem Cells ,Middle Aged ,Cell cycle ,Molecular biology ,Cell biology ,Female ,Subculture (biology) ,Biomarkers ,Chaperonin Containing TCP-1 ,Molecular Chaperones - Abstract
Although previous studies have reported the effects of extensive subculturing on proliferation rates and osteogenic potential of human mesenchymal stem cells (hMSCs), the results remain controversial. The aim of our study was to characterize the proliferation and osteogenic potential of hMSCs during serial subculture, and also to identify proteins that are differentially regulated in hMSCs during serial subculture and osteogenic differentiation using proteome analysis. Here we show that the proliferation and osteogenic capacity of hMSCs decrease during serial subculturing. Several proteins were shown to be differentially regulated during serial subculture; among these the expression of T-complex protein 1 α subunit (TCP-1α), a protein known to be associated with cell proliferation, cell cycle, morphological changes, and apoptosis, gradually decreased during serial subculture. Among proteins that were differentially regulated during osteogenic differentiation, chloride intracellular channel 1 (CLIC1) was downregulated only during the early passages eukaryotic translation elongation factor, and acidic ribosomal phosphoprotein P0 was downregulated during the middle passages, while annexin V, LIM, and SH3 domain protein 1 (LASP-1), and 14-3-3 protein gamma (YWHAG) were upregulated during the later passage. These studies suggest that differentially regulated passage-specific proteins may play a role in the decrease of osteogenic differentiation potential under serial subculturing. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:2059–2071, 2006
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- 2006
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45. A direct sandwich ELISA to detect antibodies against the C-terminal region of merozoite surface protein 1 could be a useful diagnostic method to identify Plasmodium vivax exposed persons
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Seung-Won Lee, Kook Jin Lim, Mi Jin Sohn, Hyung Cheol Kim, Yu Sam Kim, Young Yil Bahk, Jae-Won Park, and Jae Hoon Oh
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Adult ,Male ,Recombinant Fusion Proteins ,Molecular Sequence Data ,Plasmodium vivax ,Antibodies, Protozoan ,Enzyme-Linked Immunosorbent Assay ,Polymerase Chain Reaction ,law.invention ,Apicomplexa ,Species Specificity ,Sequence Analysis, Protein ,law ,parasitic diseases ,Malaria, Vivax ,medicine ,Animals ,Humans ,Amino Acid Sequence ,Cloning, Molecular ,Peptide sequence ,Merozoite Surface Protein 1 ,Polymerase chain reaction ,Sequence Homology, Amino Acid ,General Veterinary ,biology ,Antibody titer ,Blood Screening ,Reproducibility of Results ,General Medicine ,medicine.disease ,biology.organism_classification ,Virology ,Molecular biology ,Infectious Diseases ,Insect Science ,biology.protein ,Parasitology ,Antibody ,Malaria - Abstract
We expressed a C-terminal 108-aa region of the Plasmodium vivax merozoite surface protein 1 (PvMSP1c) excluding the C-end transmembrane region in Escherichia coli in order to evaluate the antibody level to MSP in Korean malaria patients. We optimized a direct sandwich enzyme-linked immunosorbent assay (ELISA) method to simultaneously determine the total antibody levels, including IgG and IgM, to PvMSP1c. If the cut-off for seropositivity was determined as the mean+3SD of the antibody levels of the negative control group, the antibody levels were positive in 99.5% of the patient group (sensitivity 199/200). The antibody levels were negative in 99.4% of the negative control group (specificity 504/507). The positive reactions in the negative control group came from non-specific reactions, as confirmed by a competition assay. This direct sandwich ELISA for PvMSP1c antibody could prove to be a useful tool for the diagnosis of malaria patients and for blood screening in blood banks.
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- 2002
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46. Identification of cDNA Encoding a Serine Protease Homologous to Human Complement C1r Precursor from Grafted Mouse Skin
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Young Yil Bahk, Zae Young Ryoo, Sung June Byun, Jong-Yuk Yi, Kyoung-Eun Kim, Tae-Yoon Kim, Ha-Young Hwang, and Jung-Woong Lee
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Proteases ,DNA, Complementary ,medicine.medical_treatment ,Molecular Sequence Data ,Gene Expression ,Dermatology ,Polymerase Chain Reaction ,Biochemistry ,Classical complement pathway ,Mice ,Complementary DNA ,Sequence Homology, Nucleic Acid ,medicine ,Animals ,Humans ,Peptide sequence ,Molecular Biology ,Skin ,Serine protease ,Protease ,biology ,Sequence Homology, Amino Acid ,cDNA library ,Complement C1r ,Gene Expression Profiling ,Serine Endopeptidases ,Cell Biology ,Molecular biology ,Immunohistochemistry ,Recombinant Proteins ,Complement system ,biology.protein - Abstract
We isolated a cDNA clone from grafted mouse skin that encodes a serine protease homologous to human C1r. The C1r protease is involved in the activation of the first component of the classical pathway in the complement system. In order to identify novel transcripts whose expression is regulated in grafted mouse skin, we first perfomed differential display reverse transcription polymerase chain reaction analysis and obtained 18 partial cDNA clones whose protein products are likely to play an important role in allograft rejection. One of these showed significant sequence homology with human complement C1r precursor. The other clones displayed no homology to any known sequences, however. Northern blot analysis demonstrated that the level of this transcript was upregulated in day 8 postgrafted skin. The full-length cDNA 2121 nucleotides in length obtained from screening a mouse skin cDNA library contained a single open reading frame encoding 707 amino acid residues with a calculated molecular weight of 80,732 Da. Its deduced amino acid sequence revealed an 81% identity and 89% similarity to the human C1r counterpart. In particular, mouse C1r contained His 501 , Asp 559 , and Ser 656 , which were conserved among this group of serine proteases. This protein was thus designated as mouse C1r. We have expressed a truncated fragment of C1r protein without the N-terminal hydrophobic sequence in Escherichia coli and generated a polyclonal antibody against it. Subsequent immunohistochemical analysis confirmed that mouse C1r was significantly expressed 8 d after the skin graft in both allografted and autografted skins, compared with normal skins. These collective data suggest that a component of the complement system, C1r, might contribute to the graft versus host immune responses in mice.
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- 2001
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47. [Untitled]
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Tae-Yoon Kim, Sun-Hee Park, Kyoung-Eun Kim, Sung June Byun, Zae Young Ryoo, Ha-Young Hwang, Young Yil Bahk, Jung-Woong Lee, Jeehee Youn, Jin-Hoi Kim, and Myung-Ok Kim
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Genetically modified mouse ,medicine.medical_specialty ,Expression vector ,Urinary bladder ,Monocyte ,Transgene ,Biology ,Molecular biology ,Endocrinology ,Granulocyte macrophage colony-stimulating factor ,medicine.anatomical_structure ,Internal medicine ,Gene expression ,Genetics ,medicine ,Animal Science and Zoology ,Northern blot ,Agronomy and Crop Science ,Biotechnology ,medicine.drug - Abstract
We have generated transgenic mice expressing human granulocyte macrophage-colony stimulating factor (hGM-CSF) in urine. In particular, the expression plasmid DNA containing mouse uroplakin II promoter was used to direct uroepithelium-specific transcription of transgene. In this study, hGM-CSF transcript was detected only in bladder uroepithelium as determined by northern blot analysis. Furthermore, hGM-CSF protein was detected in the suprabasal layer of the uroepithelium and ureter by immunohistochemistry. The hGM-CSF was secreted into urine at high level (up to 180 ng/ml), and enhanced proliferation of hGM-CSF-dependent human acute monocyte leukemic cells, suggesting that transgenic urine-derived hGM-CSF was bioactive. This is the first case of demonstrating biological activity of a cytokine produced in the urine of a transgenic animal. Our results demonstrate that bladder can be used as a bioreactor to produce biologically important substances. In addition, it suggests a potential application of bladder expression system to livestock for high-yield production of pharmaceuticals.
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- 2001
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48. Structural and Immunological Characteristics of a 28-Kilodalton Cruzipain-Like Cysteine Protease ofParagonimus westermaniExpressed in the Definitive Host Stage
- Author
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Seung Yull Cho, Yoon Kong, Doo-Hee Yun, Young-Yil Bahk, Shin-Yong Kang, Joon-Yong Chung, and Young-Bae Chung
- Subjects
Microbiology (medical) ,Paragonimus westermani ,Proteases ,Paragonimiasis ,Molecular Sequence Data ,Clinical Biochemistry ,Immunology ,Paragonimus ,Protozoan Proteins ,Cruzipain ,Immunologic Tests ,Gene Expression Regulation, Enzymologic ,Dogs ,Complementary DNA ,Animals ,Immunology and Allergy ,Amino Acid Sequence ,Structural motif ,Peptide sequence ,Genes, Helminth ,In Situ Hybridization ,Phylogeny ,DNA Primers ,Base Sequence ,Sequence Homology, Amino Acid ,biology ,cDNA library ,Gene Expression Regulation, Developmental ,biology.organism_classification ,Molecular biology ,Cysteine protease ,Molecular Weight ,Cysteine Endopeptidases ,Biochemistry ,Cats ,Microbial Immunology - Abstract
A complete cDNA sequence encoding a 28-kDa cruzipain-like cysteine protease of adultParagonimus westermani, termed Pw28CCP, was isolated from an adult cDNA library. The cDNA contained a single open reading frame of 975 bp encoding 325 amino acids, which exhibited the structural motif and domain organization characteristic of cysteine proteases of non-cathepsin Bs including a hydrophobic signal sequence, an ERFNIN motif, and essential cysteine residues as well as active sites in the mature catalytic region. Analysis of its phylogenetic position revealed that this novel enzyme belonged to the cruzipain-like cysteine proteases. The sequence of the first 13 amino acids predicted from the mature domain of Pw28CCP was in accord with that determined from the native 28-kDa enzyme purified from the adult worm. Expression of Pw28CCP was observed specifically in juvenile and adult worms, with a location in the intestinal epithelium, suggesting that this enzyme could be secreted and involved in nutrient uptake and immune modulation. The recombinant protein expressed inEscherichia coliwas used to assess antigenicity by immunoblotting with sera from patients with active paragonimiasis and from those with other parasitic infections. The resulting sensitivity of 86.2% (56 of 65 samples) and specificity of 98% (147 of 150 samples) suggest its potential as an antigen for use in immunodiagnosis.
- Published
- 2000
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49. Immobilization of horseradish peroxidase on multi-walled carbon nanotubes and its enzymatic stability
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Young Yil Bahk, Kook Jin Lim, Bum Joon Kim, Kyung Hwa Yoo, and Bong Keun Kang
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chemistry.chemical_classification ,biology ,medicine.diagnostic_test ,food and beverages ,General Physics and Astronomy ,Polymer ,Carbon nanotube ,Horseradish peroxidase ,Enzyme assay ,law.invention ,Matrix (chemical analysis) ,chemistry.chemical_compound ,Enzyme ,chemistry ,law ,Immunoassay ,biology.protein ,medicine ,Organic chemistry ,General Materials Science ,Polystyrene ,Nuclear chemistry - Abstract
We here demonstrate the use of multi-walled carbon nanotubes (MWNTs) as a platform matrix for immunoassay using horseradish peroxidase (HRP) as a model protein. After immobilization of HRP onto MWNTs using 1-pyrenebutanoic acid, succinimidyl ester as a cross-linker, the protein-loading capacity of MWNTs was determined by measuring the enzyme activity of immobilized HRP. We also compared the protein binding capacity of MaxiSorp™ – a commercially available polystyrene based microplate – with that of MWNTs. In addition, we assayed the enzyme activity of immobilized HRP in various pH or at high temperature (90 °C) in order to examine whether the stability of the immobilized HRP in harsh environments would be changed depending upon the polymer used as a matrix.
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- 2009
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50. A Recombinant 10‐kDa Protein ofTaenia soliumMetacestodes Specific to Active Neurocysticercosis
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Young Yil Bahk, Shin-Yong Kang, Joon-Yong Chung, Sun Huh, Seung Yull Cho, and Yoon Kong
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Male ,Recombinant Fusion Proteins ,Immunoblotting ,Molecular Sequence Data ,Neurocysticercosis ,Antibodies, Helminth ,Sensitivity and Specificity ,law.invention ,Open Reading Frames ,Antigen ,law ,Complementary DNA ,parasitic diseases ,Taenia solium ,medicine ,Animals ,Humans ,Immunology and Allergy ,Amino Acid Sequence ,Cloning, Molecular ,Base Sequence ,Sequence Homology, Amino Acid ,Taenia ,biology ,urogenital system ,Cysticercosis ,Middle Aged ,medicine.disease ,Virology ,Molecular biology ,Fusion protein ,Recombinant Proteins ,medicine.drug_formulation_ingredient ,Infectious Diseases ,Antigens, Helminth ,biology.protein ,Recombinant DNA ,Female ,Antibody ,Sequence Alignment - Abstract
Neurocysticercosis (NCC) is an important cause of neurological disease worldwide. A 10-kDa antigen of Taenia solium metacestodes (TsMs) has been shown to be specific for immunodiagnosis of NCC. Screening of a TsM complementary DNA (cDNA) library isolated a cDNA encoding this protein. The cloned cDNA contained a 258-bp complete open-reading frame that encodes an 86-amino acid polypeptide with a calculated molecular weight of 9582 Da. It showed 73% homology with a 10-kDa antigen of T. crassiceps. The recombinant protein was expressed bacterially as a fusion protein at a high level. In immunoblot with recombinant protein, 97% (184/190) of sera from patients with active NCC showed strong reactivity, whereas 14% (4/29) of those from patients with chronic calcified NCC reacted weakly. In 180 sera from other patients with parasitic infections and from normal controls, it showed 98% specificity. A single recombinant TsM antigen has a high potential for serological differentiation of active NCC.
- Published
- 1999
- Full Text
- View/download PDF
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