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Park CB, Kang YN, Jang H, Kim YS, Choi BO, Son SH, Song JH, Choi KH, Lee YK, Sung W, Kim JL. Evaluation of Usefulness of Yeast-Based Biological Phantom and Preliminary Study for Verification of Hypoxic Effect of Flash Radiotherapy. Int J Radiat Oncol Biol Phys 2023; 117:e704. [PMID: 37786063 DOI: 10.1016/j.ijrobp.2023.06.2193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) As a basic hypothesis for the effectiveness of flash radiation therapy, the effect of preserving normal tissue during flash radiation is due to the instantaneous chemical depletion of oxygen. A yeast-based biological phantom was created to verify the hypoxic effect of flash radiation therapy. A study to upgrade the previously developed X-Band LINAC to a flash irradiation mode is in progress, and a preceding study is conducted to evaluate the usefulness of a yeast-based biological phantom manufactured by analyzing the change in oxygen by irradiating a high dose in a general radiation therapy device. MATERIALS/METHODS Freeze-dried yeast sample (Saccharomyces cerevisiae, S288C) is activated and sub-cultured. For mass production of yeast samples, yeast culture medium is prepared by adding yeast colonies to the ypd medium. This study was conducted to verify the hypoxic effect among the biological mechanisms that occur during flash radiation therapy at the basic stage, and the oxygen concentration change during general radiation irradiation was measured in real time using a DO (Dissolved oxygen) meter and fiber optic sensor designed to do that. To prevent scatter, which is a concern during flash irradiation, the fiber form was used, and precise experiments are possible as a non-invasive oxygen concentration measurement method. Based on 10MV of general radiation therapy device, high-dose radiation of 500-10,000 cGy is irradiated to measure real-time oxygen concentration change. RESULTS As a result of irradiation with high-dose (500-10,000 cGy) radiation of general LINAC, it was confirmed that the oxygen concentration of the yeast culture medium decreased by 5.7-63.2%, and the usefulness of the biological phantom fabricated based on the yeast culture medium was evaluated. CONCLUSION Prior to the analysis of oxygen concentration change in yeast cells during X-Band LINAC flash irradiation, a preliminary study was conducted at a high dose in a general LINAC to obtain a significant result of oxygen concentration change and confirm the usefulness of the yeast-based biological phantom. Prior research was conducted and verified as a general irradiation experiment using a yeast-based biological phantom manufactured based on a DO meter and a fiber optic oxygen sensor. After irradiation with high-dose radiation, the oxygen concentration of the yeast culture medium was measured 5 times, and it was confirmed that there was a change in oxygen concentration of 5.7-63.2%, verifying the usefulness and stability of the biological phantom. The usefulness of the yeast-based biological phantom for high doses was confirmed, and it is expected that the usefulness of the biological phantom for flash radiation can be verified by additionally measuring the change in oxygen concentration of the biological phantom according to the high dose rate in the future.
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Affiliation(s)
- C B Park
- Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - Y N Kang
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - H Jang
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - Y S Kim
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - B O Choi
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - S H Son
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - J H Song
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - K H Choi
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - Y K Lee
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - W Sung
- Department of Biomedical Engineering and Department of Biomedicine and Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, Korea, Republic of (South) Korea
| | - J L Kim
- Electro-Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan, Korea, Republic of (South) Korea
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Yoon S, Son SH, Kim YB, Seo KW, Lee YJ. Molecular characteristics of optrA-carrying Enterococcus faecalis from chicken meat in South Korea. Poult Sci 2020; 99:6990-6996. [PMID: 33248615 PMCID: PMC7704738 DOI: 10.1016/j.psj.2020.08.062] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 08/14/2020] [Accepted: 08/19/2020] [Indexed: 02/06/2023] Open
Abstract
The purpose of this study was to identify the genetic environment of optrA gene in linezolid (LZD)-resistant Enterococcus faecalis from chicken meat and to describe the probable mechanism of dissemination of the optrA gene through plasmid or chromosomal integration. Whole genome sequencing and analysis revealed that all 3 E. faecalis isolates confirmed as LZD- and chloramphenicol-resistant carried fexA adjacent to the optrA gene as well as a variety of resistance genes for macrolides, tetracyclines, and aminoglycosides, simultaneously. But, the other genes conferring LZD resistance, cfr and poxtA, were not detected in those strains. Two isolates harboring the optrA gene in their chromosomal DNA showed >99% similarity in arrangement to the transposon Tn6674 and the transposase genes, tnpA, tnpB, and tnpC and were located in the first open reading frame for transposase. One isolate harboring an optrA-carrying plasmid also showed >99% similarity with the previously reported pE439 plasmid but had 2 amino acid changes (Thr96Lys and Tyr160Asp) and a higher minimum inhibitory concentration against LZD of 16 mg/L than that of pE439 (8 mg/L). Mobile genetic elements such as transposons or plasmids flanking the optrA gene conduct a crucial role in the dissemination of antimicrobial resistance genes. Further investigations are required to identify the way by which optrA is integrated into chromosomal DNA and plasmids.
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Affiliation(s)
- Sunghyun Yoon
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Se Hyun Son
- Animal Disease Diagnostic Division, Animal and Plant Quarantine Agency, Gimcheon-si, Gyeongsangbuk-do 39660, Republic of Korea
| | - Yeong Bin Kim
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Kwang Won Seo
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
| | - Young Ju Lee
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea.
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Yoon MY, Kim YB, Ha JS, Seo KW, Noh EB, Son SH, Lee YJ. Molecular characteristics of fluoroquinolone-resistant avian pathogenic Escherichia coli isolated from broiler chickens. Poult Sci 2020; 99:3628-3636. [PMID: 32616259 PMCID: PMC7597827 DOI: 10.1016/j.psj.2020.03.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 02/13/2020] [Accepted: 03/21/2020] [Indexed: 11/30/2022] Open
Abstract
Avian pathogenic Escherichia coli (APEC) is a major pathogen in the poultry industry worldwide including Korea. In this study, the phenotypic and genotypic characteristics of 33 fluoroquinolone (FQ)-resistant APEC isolates from broilers were analyzed. All FQ-resistant APEC isolates showed amino acid exchanges at both gyrA and parC and high minimal inhibitory concentrations for FQs. A total of 11 (33.3%) isolates were positive for the plasmid-mediated quinolone resistance (PMQR) genes, qnrA (8 isolates) and qnrS (3 isolates), and showed multidrug resistance. Among the 11 PMQR-positive isolates, 1 and 2 isolates carried blaCTX-1 and blaCTX-15, respectively, as extended-spectrum β-lactamase (ESBL) producers, and the non-ESBL gene, blaTEM-1, was found in 4 isolates. Among 3 aminoglycoside-resistant isolates, aac(3)-II was only detected in 1 isolate. All 8 APEC isolates with resistance to tetracycline carried the tetA gene. Overall, 6 of the 7 trimethoprim-sulfamethoxazole-resistant isolates carried the sul1 or sul2 genes, while only 2 of the 8 chloramphenicol-resistant isolates carried the catA1 gene. Although 9 isolates carried class I integrons, only 4 isolates carried the gene cassettes dfrA12-aadA2 (2 isolates), dfrA17-aadA5 (1 isolate), extX-psp-aadA2 (1 isolate), and dfrA27 (1 isolate). The most common plasmid replicon was FIB (8 isolates, 72.7%), followed by K/B (4 isolates, 36.4%). Antimicrobial resistance monitoring and molecular analysis of APEC should be performed continuously to surveil the transmission between poultry farms.
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Affiliation(s)
- Mi Young Yoon
- Quality Management Department, Samhwa GPS Breeding Agri. Inc., Hongseong-gun, Chung Nam, 32291, Republic of Korea
| | - Yeong Bin Kim
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Buk-gu, Daegu, 41566, Republic of Korea
| | - Jong Su Ha
- Quality Management Department, Samhwa GPS Breeding Agri. Inc., Hongseong-gun, Chung Nam, 32291, Republic of Korea
| | - Kwang Won Seo
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, 39762, USA
| | - Eun Bi Noh
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Buk-gu, Daegu, 41566, Republic of Korea
| | - Se Hyun Son
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Buk-gu, Daegu, 41566, Republic of Korea
| | - Young Ju Lee
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Buk-gu, Daegu, 41566, Republic of Korea.
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Seo KW, Shim JB, Kim YB, Son SH, Bi Noh E, Yoon S, Lim SK, Ju Lee Y. Impacts and characteristics of antimicrobial resistance of Escherichia coli isolates by administration of third-generation cephalosporins in layer hatcheries. Vet Microbiol 2020; 243:108643. [PMID: 32273023 DOI: 10.1016/j.vetmic.2020.108643] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 03/05/2020] [Accepted: 03/17/2020] [Indexed: 10/24/2022]
Abstract
We investigated the characteristics and persistence of Escherichia coli resistant to third-generation cephalosporins (3GCs) by early administration of ceftiofur or gentamicin and to analyze the impact of 3GC use in hatcheries. We studied 10 ceftiofur-treated flocks (CTFs) and 10 gentamicin-treated flocks (GTFs) of layers. Fecal samples were collected at 1, 2, 4, 8, 18, and 30 weeks of age for all flocks. Among the 446 E. coli isolates, 58 (29.0 %) of 200 isolates in CTFs were identified as 3GC-resistant E. coli and 28 (11.4 %) of 246 isolates in GTFs were identified as 3GC-resistant E. coli. The presence of 3GC-resistant E. coli isolates at 1, 2, and 4 weeks was significantly higher in CTFs than in GTFs (p < 0.05). Moreover, the rate of resistance to 3GCs gradually decreased from 83.3 % at 1 week of age to 4.4 % at 30 weeks of age in CTFs. Of the 86 3GC-resistant E. coli isolates, 32 isolates had β-lactamase-encoding gene: blaCTX-M-14 (ten isolates), blaCTX-M-15 (three isolates), blaCMY-2 (five isolates), and blaTEM-1 (twenty-five isolates) genes. Plasmid replicon typing revealed that blaCTX-M-14, blaCTX-M-15, blaCMY-2, and blaTEM-1 were located on F, F and FIB, I1 and K, and I1 and FII, respectively. Furthermore, 18 isolates carried class 1 integrons, with four different gene cassettes. These results revealed that ceftiofur used in hatcheries can lead to an increase in the number of 3GC-resistant E. coli with many characteristics. A voluntary ban must be imposed on the use of 3GCs for 1-day-old chicks in poultry industry.
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Affiliation(s)
- Kwang Won Seo
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State 39762, USA; College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Jong Bo Shim
- Korean Poultry TS Co., Ltd., Icheon 17415, Republic of Korea
| | - Yeong Bin Kim
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Se Hyun Son
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Eun Bi Noh
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Sunghyun Yoon
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Suk-Kyung Lim
- Animal and Plant Quarantine Agency, Ministry of Agriculture, Food and Rural Affairs, Gimcheon 39660, Republic of Korea
| | - Young Ju Lee
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea.
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Noh EB, Kim YB, Seo KW, Son SH, Ha JS, Lee YJ. Antimicrobial resistance monitoring of commensal Enterococcus faecalis in broiler breeders. Poult Sci 2020; 99:2675-2683. [PMID: 32359604 PMCID: PMC7597544 DOI: 10.1016/j.psj.2020.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 01/09/2020] [Accepted: 01/09/2020] [Indexed: 12/19/2022] Open
Abstract
Enterococcus faecalis (E. faecalis) has rapidly acquired resistance to multiple antimicrobials, and the antimicrobial resistance of E. faecalis from broiler breeders has been implicated in its vertical transmission to their offspring. The objective of this study was to investigate the antimicrobial resistance and genetic diversity of commensal E. faecalis isolated from the broiler breeder farms. Among a total of 229 E. faecalis isolates from 9 broiler breeder farms, the highest resistance rate was observed in tetracycline (78.2%), followed by doxycycline (58.1%) and erythromycin (43.7%), and the prevalence of antimicrobial resistance showed significant differences among the 9 broiler breeder farms (P < 0.05). The tetM gene (77.1%) and ermB gene (85.0%) were detected at the highest levels in 179 TE-and 100 E-resistant isolates, respectively. Twenty-four high-level gentamicin-resistant isolates carried aac(6″)Ie-aph(2″)-la gene, and 9 high-level ciprofloxacin-resistant isolates showed point mutations in both gyrA and parC genes. All high-level gentamicin-resistant or high-level ciprofloxacin-resistant isolates showed one of the two different virulence gene patterns, ace-asa1-efaA-gelE complex or ace-efaA-gelE complex. These results indicate that constant epidemiological monitoring at the breeder level is required to prevent the pyramidal transmission of antimicrobial-resistant E. faecalis.
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Affiliation(s)
- Eun Bi Noh
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Yeong Bin Kim
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Kwang Won Seo
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea; Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State 39762, USA
| | - Se Hyun Son
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Jong Su Ha
- Samhwa GPS Breeding Agri. Inc., Hongseong 32291, Republic of Korea
| | - Young Ju Lee
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea.
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Kim YB, Seo KW, Shim JB, Son SH, Noh EB, Lee YJ. Molecular characterization of antimicrobial-resistant Enterococcus faecalis and Enterococcus faecium isolated from layer parent stock. Poult Sci 2020; 98:5892-5899. [PMID: 31180127 DOI: 10.3382/ps/pez288] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/01/2019] [Indexed: 11/20/2022] Open
Abstract
Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) are ubiquitous intestinal bacteria in humans and animals that can easily acquire antimicrobial resistance, which allows them to have roles as antimicrobial resistance indicators. In addition, layer parent stock produces thousands of eggs for the production of commercial laying hens and can transfer a variety of viral and bacterial agents to chicks. The objective of this study was to determine the prevalence and characteristics of antimicrobial-resistant E. faecalis and E. faecium isolated in the layer parent stock level of the egg-layer operating system in South Korea. A total of 129 E. faecalis and 166 E. faecium isolates from 74 flocks of 30 layer parent stock were tested for resistance in this study. The prevalence of doxycycline- (51.9%), erythromycin- (53.5%), high-level gentamicin- (13.2%), high-level kanamycin- (31.0%), high-level streptomycin- (30.2%), and tetracycline- (64.3%) resistant E. faecalis isolates were higher than those for E. faecium isolates (P < 0.05). The ermB gene was detected in 66 (95.7%) erythromycin-resistant E. faecalis isolates, which was higher than that of 32 (71.7%) erythromycin-resistant E. faecium isolates. Twenty-one high-level gentamicin-resistant Enterococcus spp. (17 E. faecalis and 4 E. faecium) carried at least one aminoglycoside-modifying enzyme gene, aac(6')Ie-aph(2')-Ia or ant(6)-Ia. Fourteen isolates that harbored both aac(6')Ie-aph(2')-Ia and ant(6)-Ia exhibited pattern A with IS256 at both ends. Ten high-level ciprofloxacin-resistant Enterococcus spp. (8 E. faecalis and 2 E. faecium) showed amino acid changes from serine to isoleucine at codons 83 in gyrA, and 80 in parC. Also, the virulence genes ace, asa1, efaA, and gelE were detected in this study. To the best of our knowledge, this is the first study to examine the prevalence and characteristics of antimicrobial-resistant E. faecalis and E. faecium isolates in the layer parent stock. Our findings support the need for a surveillance program to monitor the emergence of antimicrobial-resistant E. faecalis and E. faecium in layer operating system.
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Affiliation(s)
- Yeong Bin Kim
- College of Veterinary Medicine and Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Kwang Won Seo
- College of Veterinary Medicine and Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Jong Bo Shim
- Korean Poultry TS Co., Ltd., Incheon 17415, Republic of Korea
| | - Se Hyun Son
- College of Veterinary Medicine and Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Eun Bi Noh
- College of Veterinary Medicine and Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Young Ju Lee
- College of Veterinary Medicine and Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
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Kim YB, Seo KW, Son SH, Noh EB, Lee YJ. Genetic characterization of high-level aminoglycoside-resistant Enterococcus faecalis and Enterococcus faecium isolated from retail chicken meat. Poult Sci 2020; 98:5981-5988. [PMID: 31298294 DOI: 10.3382/ps/pez403] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 06/18/2019] [Indexed: 01/08/2023] Open
Abstract
Retail chicken meat can play a role in the transfer of drug resistance to humans through the handling or ingestion of improperly cooked meat contaminated with resistant enterococci. In fact, high-level aminoglycoside-resistance (HLAR) in enterococci identified in human cases. Therefore, the prevalence and genetic characterization of HLAR in enterococci in retail chicken meat were investigated in this study. Of the 345 enterococci strains, 29 (8.7%) showed HLAR. All HLAR in enterococci carried at least 1 of 2 aminoglycoside-modifying enzyme genes, aac(6')Ie-aph(2″)-Ia and ant(6)-Ia. Among the 13 isolates that carried aac(6')Ie-aph(2″)-Ia, 3 had pattern A, with IS256 at both ends, and the other 10 had pattern D, without IS256 at both ends. All HLAR in enterococci also showed multidrug resistance. Among the 24 erythromycin-resistant enterococci, 19 (79.2%) harbored the ermB gene, and one (4.2%) harbored both the ermB and ermA genes. A total of 21 enterococci were tetracycline-resistant and harbored one or more of the following tetracycline resistance genes tet(M), tet(L), and tet(O). The Int-Tn gene was detected in one isolate (3.4%) carrying the tet(M) and ermB genes. All 4 chloramphenicol-resistant isolates carried either the phenicol resistance gene cfr alone (one isolate), both cfr and fexA (one isolate), or both fexA and optrA (2 isolates). Four efflux pump genes, efr(A), efr(B), emeA, and lsa, were detected in all HLAR in Enterococcus faecalis isolates. These results improve our understanding of the transmission dynamics of HLAR in enterococci from non-hospital sources to humans.
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Affiliation(s)
- Yeong Bin Kim
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Kwang Won Seo
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea.,Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State 39762, USA
| | - Se Hyun Son
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Eun Bi Noh
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Young Ju Lee
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea
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Noh EB, Kim YB, Jeon HY, Seo KW, Son SH, Lee YJ. Antimicrobial Resistance and Genetic Diversity of Salmonella Serotypes Recovered from Edible Pork Offal from Korea. Microb Drug Resist 2019; 25:1514-1520. [PMID: 31369345 DOI: 10.1089/mdr.2019.0010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Although edible offal can be easily contaminated with foodborne bacteria and regarded as important transfers of antimicrobial resistance to humans, the characterization of bacteria from edible offal have not been researched sufficiently. This study is the first to focus on the molecular characterization of Salmonella isolated from edible pork offal. From a total of 52 Salmonella isolates from edible pork offal, 44 (80.7%) were resistant to at least one antimicrobial agent and 24 (46.2%) exhibited multidrug resistance (MDR). All MDR Salmonella were also resistant to β-lactams and 12 (50.0%) of the isolates were positive for blaTEM-1. Eleven (68.8%) of the 16 gentamicin-resistant isolates harbored the ant(2'')-I gene. Among 18 tetracycline-resistant isolates, tetA and tetB genes were found in 9 (50.0%) and 3 (16.7%) isolates, respectively. The sul1 gene was identified in 9 (81.8%) of 11 trimethoprim/sulfamethoxazole-resistant isolates, and the cmlA gene was identified in only 2 (18.1%) among 11 chloramphenicol-resistant isolates. Eighteen (75.0%) of the 24 MDR Salmonella were identified as containing class 1 integrons, within which dfrA12-aadA2 (55.6%) was the most prevalent resistance gene cassettes. Twenty-one (87.5%) of the MDR isolates were also found to have the plasmid replicons. Replicon B/O (41.7%) was the most prevalent replicon types. These results suggest that edible pork offal can become a reservoir that not only harbors MDR Salmonella, but also contributes to their dissemination through cross-contamination processes.
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Affiliation(s)
- Eun Bi Noh
- Department of Public Health, College of Veterinary Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Yeong Bin Kim
- Department of Public Health, College of Veterinary Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Hye Young Jeon
- Department of Public Health, College of Veterinary Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Kwang Won Seo
- Department of Public Health, College of Veterinary Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Se Hyun Son
- Department of Public Health, College of Veterinary Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Young Ju Lee
- Department of Public Health, College of Veterinary Medicine, Kyungpook National University, Daegu, Republic of Korea
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Son SH, Seo KW, Kim YB, Jeon HY, Noh EB, Lee YJ. Molecular Characterization of Multidrug-Resistant Escherichia coli Isolates from Edible Offal in Korea. J Food Prot 2019; 82:1183-1190. [PMID: 31233359 DOI: 10.4315/0362-028x.jfp-18-458] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
HIGHLIGHTS Edible offal is significantly contaminated by antimicrobial-resistant Escherichia coli. E. coli from edible offal is harboring various antimicrobial resistance and virulence genes. Improvements in hygienic conditions of edible offal production is required.
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Affiliation(s)
- Se Hyun Son
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea (ORCID: https://orcid.org/0000-0002-4754-0931 [Y.B.K.]; https://orcid.org/0000-0003-1903-1133 [H.Y.J.])
| | - Kwang Won Seo
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea (ORCID: https://orcid.org/0000-0002-4754-0931 [Y.B.K.]; https://orcid.org/0000-0003-1903-1133 [H.Y.J.])
| | - Yeong Bin Kim
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea (ORCID: https://orcid.org/0000-0002-4754-0931 [Y.B.K.]; https://orcid.org/0000-0003-1903-1133 [H.Y.J.])
| | - Hye Young Jeon
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea (ORCID: https://orcid.org/0000-0002-4754-0931 [Y.B.K.]; https://orcid.org/0000-0003-1903-1133 [H.Y.J.])
| | - Eun Bi Noh
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea (ORCID: https://orcid.org/0000-0002-4754-0931 [Y.B.K.]; https://orcid.org/0000-0003-1903-1133 [H.Y.J.])
| | - Young Ju Lee
- College of Veterinary Medicine & Zoonoses Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea (ORCID: https://orcid.org/0000-0002-4754-0931 [Y.B.K.]; https://orcid.org/0000-0003-1903-1133 [H.Y.J.])
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Shin HJ, Song JH, Jung JY, Kwak YK, Kay CS, Kang YN, Choi BO, Jang HS, Son SH. Advantage of 3D volumetric dosemeter in delivery quality assurance of dynamic arc therapy: comparison of pencil beam and Monte Carlo calculations. Br J Radiol 2013; 86:20130353. [DOI: 10.1259/bjr.20130353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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11
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Hong JY, Kim GW, Kim CU, Cheon GS, Son SH, Lee JY, Lee YH, Lee JH, Choi BO, Kim YS, Lee SN, Jang HS, Kang YN, Yoon SC. Supine linac treatment versus tomotherapy in craniospinal irradiation: planning comparison and dosimetric evaluation. Radiat Prot Dosimetry 2011; 146:364-366. [PMID: 21515620 DOI: 10.1093/rpd/ncr190] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Craniospinal irradiation (CSI) is the standard treatment of primary intracranial tumour with risk of leptomeningeal dissemination. However, supine setup field-in-field technique does not need inter-fractional junction shift. Recently, the studies of CSI with tomotherapy showed excellent target coverage and tolerable normal organ dose in paediatric patients. The planning comparison and dosimetric difference between conventional radiotherapy and tomotherapy are presented. Three patients with central nervous system germinoma received supine CSI treatment. Normal tissue complication probability calculation was performed for parotid gland, kidney, lens, small bowel, ovary and testis. Homogenous vertebral body coverage for tomotherapy compared with conformal radiotherapy was found. The mean dose to each parotid gland decreased by 7.3 and 10 Gy, respectively, with tomotherapy. The volume of oesophagus and small bowel receiving >10 Gy was significantly lower. The V2, V5, V10 and V20 of the lungs are 81.6, 12.4, 2.3 and 0 % with tomotherapy. Tomotherapy showed excellent homogenous dose distribution through the craniospinal axis (PTV) and higher conformity index.
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Affiliation(s)
- J Y Hong
- Department of Radiation Oncology, Seoul St. Mary's Hospital, The Catholic University of Korea, #505 Banpo-dong, Seocho-gu, Seoul 137-701, Korea
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Abstract
PURPOSE To evaluate the acquisition of AAC skills during an initial clinical trial and assess subsequent transfer of the training to the home setting. METHOD A 12-year-old male with autism was first seen in a clinical setting to establish the use of a voice-output communication device. After learning to use the device to request access to preferred objects in the clinical trial, the intervention was transferred to the home. Follow-up with the parent was conducted via e-mail and telephone. Videotapes were made of initial home-based sessions to enable evaluation of the participant's progress. RESULTS The programme was successful in teaching the participant to use a portable AAC device to make requests during the clinical trial and then in two home-based activities. CONCLUSION An initial clinical trial with follow-up support for parents may be an efficient method for beginning AAC intervention and transferring the training procedures to the home setting.
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Affiliation(s)
- J Sigafoos
- Department of Special Education, University of Texas, Austin, TX 78712-1290, USA.
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Kim JS, Kwak BK, Shim HJ, Lee YC, Baik HW, Lee MJ, Han SM, Son SH, Kim YB, Tokura S, Lee BM. Preparation of doxorubicin-containing chitosan microspheres for transcatheter arterial chemoembolization of hepatocellular carcinoma. J Microencapsul 2008; 24:408-19. [PMID: 17578731 DOI: 10.1080/02652040701339213] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A new form of doxorubicin hydrochloride (DRH)-containing chitosan microspheres (CMs) was prepared by employing an expanding-loading-shrinking (E-L-S) process. One hundred mg of pre-formed CMs were soaked in absolute ethanol and then placed in reduced pressure (the expanding process). Ten mg of DRH (2 mg ml(-1)) were added into the expanded CMs (the loading process). Next the microspheres were freeze-dried (the shrinking process). As a result of this E-L-S process, 10% (w/w) DRH-containing CMs (DRH-CM) were made. During 7 days, 22.6% of the DRH was observed to be released on the in vitro drug release study. In addition, these new DRH-CMs could be used for transcatheter arterial chemoembolization (TACE) procedure in VX2 hepatic tumour models of rabbit and the anti-tumour effects of DRH-CMs were investigated. On the post-CT scan 7 days after the TACE, total infarctions of the VX2 tumour were observed in 5 rabbits among the 6 total rabbits.
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Affiliation(s)
- J S Kim
- Department of Radiology, Chung-Ang University Hospital. Heukseok-dong, Dongjak-gu, Seoul, Korea
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Khan Z, Kim SG, Jeon YH, Khan HU, Son SH, Kim YH. A plant growth promoting rhizobacterium, Paenibacillus polymyxa strain GBR-1, suppresses root-knot nematode. Bioresour Technol 2008; 99:3016-23. [PMID: 17706411 DOI: 10.1016/j.biortech.2007.06.031] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2007] [Revised: 06/04/2007] [Accepted: 06/04/2007] [Indexed: 05/16/2023]
Abstract
Exposure of root-knot nematode, Meloidogyne incognita to various concentrations (5-100%) of culture filtrate of Paenibacillus polymyxa GBR-1 under in vitro conditions significantly reduced egg hatch and caused substantial mortality of its juveniles. The increase in the exposure durations of juveniles to culture filtrate and its concentrations increased the mortality rate. Similarly, higher concentrations increased its inhibitory effect on egg hatch. In higher concentrations (25-100%) egg hatch was inhibited by 84-91% after 2 days of exposures as compared to control in sterile distilled water. Application of various concentrations of culture filtrate extract or bacterial suspension of P. polymyxa GBR-1 into potting soil infested with 2000 J2 of M. incognita, reduced the root galling and nematode populations and increased tomato plant growth and root-mass production compared with untreated control (P< or = 0.05). The beneficial effect of P. polymyxa GBR-1 into potted soil increased exponentially with the increase in dose concentrations. Root gall index was reduced from 4.8 to 1.4 and 1.8 when potting soil was treated with 10% concentrations of culture filtrate extract and bacterial suspension, respectively, compared with untreated control. Application of bacterial suspension of P. polymyxa GBR-1 into potted soil at 3 day pre-inoculation of nematode was the most effective followed by simultaneously and at 2 days post-inoculation; as root galling was reduced by 62.5%, 58.3% and 50.0%, respectively, compared with untreated control.
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Affiliation(s)
- Z Khan
- Department of Agricultural Biotechnology and Center for Plant Molecular Genetics and Breeding Research, Seoul National University, Seoul 151-921, Republic of Korea
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15
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Son SH, Choi SM, Lee YH, Choi KB, Yun SR, Kim JK, Park HJ, Kwon OW, Noh EW, Seon JH, Park YG. Large-scale growth and taxane production in cell cultures of Taxus cuspidata (Japanese yew) using a novel bioreactor. Plant Cell Rep 2000; 19:628-633. [PMID: 30754828 DOI: 10.1007/s002990050784] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A novel type of bioreactor was successfully developed for the production of taxol and its precursors by culturing cells of Taxus cuspidata (Japanese yew) on a pilot-scale. Rapidly growing cell lines were selected from callus cultures derived from immature embryos of yew. The cells were inoculated in 20-l capacity bioreactors of different types to test the growth performance. The models of small-scale bioreactors incorporated in this study included a balloon-type bubble bioreactor (BTBB), a bubble-column bioreactor (BCB), a BCB with a split-plate internal loop, a BCB with a concentric draught-tube internal loop, a BCB with a fluidized bed bioreactor, and two different models of stirred tank reactors. Among the reactors, BTBB appeared to be the most efficient in promoting cell growth. The doubling time of cell growth in BTBB was 12 days with a 30% inoculation cell density. The optimum time for medium replacement or feeding was 12-15 days after inoculation as determined by monitoring both the levels of sugars and medium conductivity. When yew tree cells were grown in different sizes (100-500-l) of BTBBs, more than 70% cell viability was recorded at the time of harvest. The growth pattern of the cells in the pilot-scale BTBB appeared to be the same as that of cells in the 20-l bioreactors. Approximately 3 mg/l of taxol and 74 mg/l total taxanes were obtained after 27 days of culture.
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Affiliation(s)
- S H Son
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - S M Choi
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - Y H Lee
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - K B Choi
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - S R Yun
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - J K Kim
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - H J Park
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - O W Kwon
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - E W Noh
- Division of Biotechnology, Forestry Research Institute, Forestry Administration, Omokdong, 44-3 beongi, Kwonseon-gu, Suwon 441-350, Republic of Korea e-mail: Fax: +82-331-290-1190, , , , , , KR
| | - J H Seon
- Department of Biological Science, University of Calgary, 2500 University Dr. N.W., Calgary, Alberta, Canada T2N1L4, , , , , , CA
| | - Y G Park
- Department of Foresty, Kyungpook National University, Taegu 702-701, Republic of Korea, , , , , , KR
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Affiliation(s)
- Y I Choi
- Forestry Research Institute, Suwon, Republic of Korea.
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Son SH, Han CK, Ahn SK, Yoon JH, No KT. Development of three-dimensional descriptors represented by tensors: free energy of hydration density tensor. J Chem Inf Comput Sci 1999; 39:601-9. [PMID: 10361730 DOI: 10.1021/ci980224p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In order to describe the degree of interaction of a molecule with its environments by descriptors, several three-dimensional descriptors have been proposed. With the physical properties calculated around a molecule, scalar, vector, and tensor (zeroth, first, and second moments) of the physical properties were calculated and were used as descriptors for calculating the similarity index between the molecules. The tensors contain the information on the spatial distribution of those physical properties around the molecule. Hydration Free Energy Density (HFED) proposed by No et al. was used to calculate HFED tensor. The descriptors were used for the similarity index calculations between substituted benzenes and between lead compounds of HIV-1 protease inhibitors. The substituted benzenes are grouped according to the similarity indices. The grouping seems reasonable from the viewpoint of a chemical sense. The lead fragments of the HIV-1 protease inhibitors have a high similarity among themselves though their chemical formulas are not very similar, the lead fragments are diverse. Although the chemical formulas are diverse, the spatial distribution of the physical properties around the molecules is similar. The descriptors have high discriminating power in the similarity calculation between the molecules.
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Affiliation(s)
- S H Son
- Department of Chemistry, Soong Sil University, Seoul, Korea
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Abstract
OBJECTIVES The significance of the coccoid forms of H. pylori is still controversial and the questions of whether these forms are viable and infective or degenerative are still open. We induced conversion from rod to coccoid forms and studied morphological changes and antigenic evolutions during this conversion and, thereby, elucidated the viability of coccoid forms. METHODS The H. pylori strain (C001) used for Western blotting was isolated from the patient with gastric cancer. The antigenic evolution during coccoid conversion of H. pylori was studied by Western blotting, using different sera from thirty patients known to be culture positive. These sera were used to reveal the total antigens of the strain cultured for 2 days (100% rod) and 15 days (> 99% coccoid). After SDS-PAGE, with 10% separating gel of total antigens (rod and coccoid), transblotting (Trans-Blot electrophoretic cell, Bio-Rad) was taken onto a nitrocellulose membrane (Bio-Rad). Then, the blots, with human sera diluted at 1/100, were developed with color reaction by goat serum anti-human IgG with alkaline phosphatase and BCIP. RESULTS The antigenic profiles were not changed in 46.7% (14/30 cases) and were changed in 53.3% (16/30 cases) during coccoid conversion. Antigenic fractions changed during coccoid conversion were protein band at 120 kDa and band at 35 kDa, and were not detected in coccus forms. The rest of the profiles were identical between rod and coccoid forms. The protein which disappeared include CagA (120 kDa) and porin, or adhesin (35 kDa). The morphological changes during coccoid conversion were U shaped at day 7, doughnut shaped at day 9 and full coccoid at day 15. CONCLUSIONS The results showed that coccoid forms of H. pylori retain cellular structures similar to rod form, and some of the antigens (CagA and porin) disappeared during coccoid conversion. Therefore, coccoid form might be viable and represent one of the stages of H. pylori biological cycle.
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Affiliation(s)
- I H Roe
- Department of Internal Medicine, College of Medicine, Dankook University, Chun-an, Korea
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Park YG, Son SH. In vitro shoot regeneration from leaf mesophyll protoplasts of hybrid poplar (Populus nigra x P. maximowiczii). Plant Cell Rep 1992; 11:2-6. [PMID: 24213027 DOI: 10.1007/bf00231829] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/1991] [Revised: 12/05/1991] [Indexed: 06/02/2023]
Abstract
Protoplasts were isolated from leaf mesophyll of hybrid poplar (Populus nigra X P. maximowiczii) with a mean yield of 10.4 x 10(6) protoplasts per g fresh weight using 2.0% Cellulase 'Onozuka' R-10, 0.8% Macerozyme R-10, 1.2% Hemicellulase, 2.0% Driselase, and 0.05% Pectolyase Y-23 with CPW salts solution containing 0.6 M mannitol, 0.002 M DTT, 3 mM MES at pH 5.6. A liquid plating method produced the highest frequency of dividing protoplasts (48.6%) using an MS medium without NH4NO3. The highest percent of colony formation was 22.8%, produced with fabric supported semi-solid (0.5% w/v) agar plating method using the same culture medium. Growing cell colonies and/or micro-calli were transferred to a fresh semisolid agar medium containing 0.44 μM BAP and 9.0 μM 2,4-D. Multiple shoots were produced from protoplast-derived callus after culture on MS medium containing 6.8 μM zeatin. After root induction on half-strength MS medium that lacked growth regulators, shoots were transferred to pots containing artificial soil mix.
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Affiliation(s)
- Y G Park
- Department of Forestry, College of Agriculture, Kyungpook National University, 702-701, Daege, Korea
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Son SH, Hall RB. Plant regeneration capacity of callus derived from leaf, stem, and root segments of Populus alba L. x P. grandidentata Michx. Plant Cell Rep 1990; 9:344-347. [PMID: 24226948 DOI: 10.1007/bf00232866] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/1990] [Revised: 08/07/1990] [Indexed: 06/02/2023]
Abstract
Expiants for establishing callus cultures originated from in vitro cultured hybrid poplar (Populus alba L. X P. grandidentata Michx.). Plant regeneration was achieved from established callus cultures derived from stem internodes (SI), leaf discs (LD), and root segments (RS). Shoot regeneration from callus occurred within 4 weeks of culture on most of the media tested. Frequency of shoot formation was greatly increased by subculturing the selected organogenic calli on regeneration media. The highest rate of multiple shoot formation (an average number of 7/SI, 11/LD, and 8/RS) was obtained by using 0.05 μM IBA in combination with 22.5 μM 2iP, 22.5 μM zeatin, and 12.5 μM 2iP, respectively. Regenerated shoots were easily rooted in polyterra(™) peat plugs in transparent plastic boxes. The rooted plantlets were subsequently transferred to pots containing an artificial potting mix.
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Affiliation(s)
- S H Son
- Department of Forestry, Iowa State University, 50011-1021, Ames, IA, USA
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Chung HJ, Chung CP, Son SH, Nisengard RJ. Actinobacillus actinomycetemcomitans serotypes and leukotoxicity in Korean localized juvenile periodontitis. J Periodontol 1989; 60:506-11. [PMID: 2677302 DOI: 10.1902/jop.1989.60.9.506] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Actinobacillus actinomycetemcomitans is though to play an important role in the pathogenesis of localized juvenile periodontitis (LJP). Preliminary data suggested that the serotype distribution of A. actinomycetemcomitans in Korea and the United States differ. This study evaluated A. actinomycetemcomitans prevalence, serotype distribution, and leukotoxicity in Korean LJP patients by culture, enzyme-linked immunosorbent assay, indirect immunofluorescence, and lactate dehydrogenase release from polymorphonuclear leukocytes exposed to A. actinomycetemcomitans. A. actinomycetemcomitans occurred in 75% of LJP lesions and 6% of normal sites with approximately equal distribution of serotype a, b, and c. Single serotypes were isolated from nine patients while three patients harbored two serotypes either in the same or different disease sites. A. actinomycetemcomitans leukotoxicity occurred in 22% isolates with a 69% prevalence. Individual sites harbored both leukotoxic and non-leukotoxic strains with no serotype association. The distribution of serotypes and leukotoxic strains of A. actinomycetemcomitans in Korean LJP patients differed from those reported in the United States. This suggests that serotype b may not be more important in the pathogenesis of LJP.
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Affiliation(s)
- H J Chung
- Department of Periodontology, College of Dentistry, Chonnam National University, Kwang Ju, Korea
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Park YG, Son SH. Regeneration of plantlets from cell suspension culture derived callus of white poplar (Populus alba L.). Plant Cell Rep 1988; 7:567-570. [PMID: 24240419 DOI: 10.1007/bf00272759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/1988] [Revised: 10/28/1988] [Indexed: 06/02/2023]
Abstract
Friable calli derived from the stem tissues of Populus alba were used to establish cell suspension cultures which were characterized for in vitro growth and regeneration capacity. Suspended cells and callus recovered from these cells were maximal on a fresh weight basis using MS liquid medium containing 0.44 μM BAP and 4.52 μM 2,4-D. Shoot regeneration from the recovered callus was observed within 30 to 40 days of culture. The number of shoots was increased by subculturing the shoot-forming callus 2 to 3 times on MS medium supplemented with 19.7 μM 2iP and 0.05 μM IBA. Regenerated shoots were easily rooted on half-strength MS medium lacking growth regulators, and the plantlets were transferred to pots containing vermiculite for greenhouse growth.
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Affiliation(s)
- Y G Park
- Department of Forestry, College of Agriculture, Kyungpook National University, 702-701, Daegu, Korea
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Son SH, Choi SM, Han SB, Chung CP. [The prevalence and antibiotic susceptibility of Capnocytophaga and Actinobacillus actinomycetemcomitans in the periodontal pockets of periodontitis patients with insulin-independent diabetes mellitus]. Taehan Chikkwa Uisa Hyophoe Chi 1986; 24:961-8. [PMID: 3474309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Chung CP, Lee YH, Choi JY, Son JU, Son SH, Choi SM, Han SB. [Isolation and identification of Bacteroides gingivalis in rapidly progressing periodontitis in Koreans]. Taehan Chikkwa Uisa Hyophoe Chi 1984; 22:865-8. [PMID: 6596344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Chang CP, Lee YK, Lee YH, Kim KS, Choi SM, Son SH, Han SB, Hwang KS. [Isolation and identification of Actinobacillus actinomycetemcomitans in Korean localized juvenile periodontitis (I)]. Taehan Chikkwa Uisa Hyophoe Chi 1984; 22:507-14. [PMID: 6592280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Son SH, Lee JH, Kim WS, Kim CG, Lee CH. [Autogenous free gingival graft. A technique and case report (author's transl)]. Taehan Chikkwa Uisa Hyophoe Chi 1973; 11:675-9. [PMID: 4523384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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