Mi Young Park

Massachusetts General Hospital, Boston, Massachusetts, United States

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Publications (47)112.57 Total impact

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    ABSTRACT: The UL112-113 region of the human cytomegalovirus (HCMV) genome encodes four phosphoproteins of 34, 43, 50, and 84 kDa that promote viral DNA replication. Co-transfection assays have demonstrated that self-interaction of these proteins via the shared N-termini is necessary for their intranuclear distribution as foci and for the efficient relocation of a viral DNA polymerase processivity factor (UL44) to the viral replication sites. However, the requirement of UL112-113 N-terminal residues for viral growth and DNA replication has not been fully elucidated. Here, we investigated the effect of deletion of the N-terminal regions of UL112-113 proteins on viral growth and oriLyt-dependent DNA replication. A deletion of the entire UL112 region or the region encoding the 25 N-terminal amino-acid residues from the HCMV (Towne strain) bacmid impaired viral growth in bacmid-transfected human fibroblast cells, indicating their requirement for viral growth. In co-immunoprecipitation assays using the genomic gene expressing the four UL112-113 proteins together, the 25 N-terminal amino-acid residues were found to be necessary for stable expression of UL112-113 proteins and their self-interaction. These residues were also required for efficient binding to and relocation of UL44, but not for interaction with IE2, an origin-binding transcription factor. In co-transfection/replication assays, replication of the oriLyt-containing plasmid was promoted by expression of intact UL112-113 proteins, but not by the expression of 25-amino-acid residue-deleted proteins. Our results demonstrate that the 25 N-terminal amino-acid residues of UL112-113 proteins that mediate self-interaction contribute to viral growth by promoting their binding to UL44 and the initiation of oriLyt-dependent DNA replication.
    No preview · Article · Aug 2015 · The Journal of Microbiology
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    ABSTRACT: Chronic kidney disease (CKD) severity is associated with increased morbidity and mortality in congestive heart failure (CHF). There is a paucity of data regarding renal improvement after cardiac resynchronization therapy (CRT) and its potential impact on clinical outcomes, especially in patients with severe CKD. This was a retrospective analysis of a prospectively collected cohort of 260 patients with CKD undergoing CRT at a single center. Renal function was compared before and after CRT. The primary endpoint was a composite of death, heart transplant, and LVAD, assessed at 5 years. Patients with more severe CKD demonstrated increased risk of death, transplant, or LVAD following CRT (p = 0.015). Renal response (eGFR improvement ≥ 10mL/min/1.73m(2) ) was observed in 14% of all patients and 28% of patients with stage IV CKD. Independent predictors of renal response included LVEF improvement (OR 1.06, CI 1.01-1.10), ACE inhibitor/ARB use (OR 4.31, CI 1.08-17.23), and advanced CKD stage (OR 2.19, CI 1.14-4.23). Renal response independently decreased hazard of the primary outcome (HR 0.24, CI 0.08-0.73, p = 0.01). Renal responders with stage IV CKD had 80% five-year event-free survival, compared to 0% for non-renal responders in stage IV (p = 0.03). Although severity of CKD is associated with poorer outcome after CRT, improvement in renal function can occur in patients across all CKD stages. Renal responders, including those with stage IV CKD, demonstrate favorable five-year outcomes. Assessment of renal response may help better prognostic outcomes following CRT. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · Jul 2015 · Pacing and Clinical Electrophysiology
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    Mi Young Park · Young Jin Kim · Hyung-Tae Lim
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    ABSTRACT: Yttria doped barium cerate (BCY) electrolyte, Ni+BCY anode supported cells were fabricated, and their stability and the mechanism of their degradation were investigated through constant current tests under various operating conditions, especially negative cell voltage operation (with respect to degradation phenomenon due to cell imbalance in a series connected stack). The results of electrochemical tests (I-V characteristics and impedance spectra) indicate that the degradation rate was significant when the cell was operated under higher current densities (regardless of the sign of cell voltage) and only the ambient air was used for the cathode. Post-material analyses revealed that microstructural and compositional changes were obvious in the BCY electrolyte and the BCY of the cathode functional layer because of BCY decomposition in the wet atmosphere at the cathode. Thus, the present work concludes that the degradation rate of BCY electrolyte-based cell depends on operating conditions, i.e., the amount of current density (the water vapor production rate at the cathode) and the air flow rate (flushing water vapor at the cathode).
    Full-text · Article · Apr 2015 · Journal of the Ceramic Society of Japan
  • Mi Young Park · Yeon-Gil Jung · Hyung-Tae Lim
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    ABSTRACT: One of the critical fuel cell degradation phenomena is ‘cell imbalance’ in a series-connected stack, which can cause abnormal operation under a negative cell voltage and consequently rapid degradation by anode interface delamination. In a previous study, the effect of electrolyte composition on the electrochemical degradation of solid oxide fuel cell (SOFC) was investigated, and it was observed that a small amount of ceria (an electronic conducting material) prevents anode delamination under abnormal (negative voltage) operation. However, the open circuit voltage (OCV) was lowered as a result of reduction of ceria. In the present study, bi-layer, YSZ (8 mol % yttria doped zirconia, a predominantly ionic conductor) at the cathode side and 8CYSZ (8 mol % ceria doped YSZ, a mixed ionic-electronic conductor) at the anode side were fabricated for anode-supported cells with a Pt probe embedded in each layer to estimate the internal oxygen chemical potential and tested under a negative voltage. The results indicated that the OCV was close to the theoretical value (similar to that of a YSZ single layer cell) and no delamination was observed under negative voltage operation (similar to the case of an 8CYSZ single-layer cell). Therefore, the bi-layer-structured electrolyte (with locally increased electronic conduction at the anode side) is effective in preventing anode/electrolyte delamination as well as maintaining open circuit voltage.
    No preview · Article · Sep 2014 · Solid State Ionics
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    ABSTRACT: BACKGROUND Cardiac resynchronization therapy (CRT) nonresponders have poor outcomes. The significance of progressive ventricular dysfunction among nonresponders remains unclear. OBJECTIVE We sought to define predictors of and clinical outcomes associated with progressive ventricular dysfunction despite CRT. METHODS We conducted an analysis of 328 patients undergoing CRT with defibrillator for standard indications. On the basis of 6-month echocardiograms, we classified patients as responders (those with a >= 5% increase in ejection fraction) and progressors (those with a >= 5% decrease in ejection fraction), and all others were defined as nonprogressors. Coprimary end points were 3-year (1) heart failure, left ventricular assist device (LVAD), transplantation, or death and (2) ventricular tachycardia (VT) or ventricular fibrillation (VF). RESULTS MuLtivariable predictors of progressive ventricular dysfunction were aldosterone antagonist use (hazard ratio [HR] 0.23; P = .008), prior valve surgery (HR 3.3; P = .005), and QRS duration (HR 0.98; P = .02). More favorable changes in ventricular function were associated with Lower incidences of heart failure, LVAD, transplantation, or death (70% vs 54% vs 330/e; P < .0001) and VT or VF (66% vs 38% vs 28%; P = .001) for progressors, nonprogressors, and responders, respectively. After multivariable adjustment, progressors remained at increased risk of heart failure, LVAD, transplantation, or death (HR 2.14; P = .0029) and VT or VF (HR 2.03; P = .046) as compared with nonprogressors. Responders were at decreased risk of heart failure, LVAD, transplantation, or death (HR 0.44; P < .0001) and VT or VF (0.51; P = .015) as compared with nonprogressors. CONCLUSION Patients with progressive deterioration in ventricular function despite CRT represent a high-risk group of nonresponders at increased risk of worsened clinical outcomes.
    Full-text · Article · Aug 2014 · Heart rhythm: the official journal of the Heart Rhythm Society
  • Mi Young Park · Hongyeul Bae · Hyung-Tae Lim
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    ABSTRACT: The stability of a solid oxide fuel cell (SOFC) stack is strongly dependent on the magnitude and profile of the internal chemical potential of the solid electrolyte. If the internal partial pressure is too high, the electrolyte can be delaminated from the electrodes. The formation of high internal pressure is attributed to a negative cell voltage, and this phenomenon can occur in a bad cell (with higher resistance) in a stack. This fact implies that the internal chemical potential plays an important role in determining the lifetime of a stack. In the present work, we fabricate planar type anode-supported cells (25 cm 2 ) with a bi-layer electrolyte (with locally increased electronic conduction at the anode side) to prevent high internal pressure, and we test the fabricated cells under a negative voltage condition. The results indicate that the addition of electronic conduction in the electrolyte can effectively depress internal pressure and improve the cell stability.
    No preview · Article · Jul 2014 · Journal of the Korean Ceramic Society
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    ABSTRACT: This study investigated the estrogen-like activity of Adenophora triphylla var. japonica, which has been shown to have pharmacological activities. Water extracts from A. triphylla (ATWE) could bind to estrogen receptors and displaced binding of E2 to ERα and ERβ. ATWE stimulated the proliferation of estrogen receptor-positive MCF-7 cells in a dose dependent manner (p<0.05). ATWE induced proliferation was blocked by the addition of the estrogen antagonist ICI 182,780 (p<0.05). Moreover, ATWE treatment caused a significant increase in mRNA expression of estrogen-responsive genes (pS2, PR, and cathepsin D; p<0.05). These results indicate that A. triphylla has estrogen-like activity and could be used to improve estrogen deficiency-related menopausal symptoms or diseases in postmenopausal women.
    No preview · Article · Dec 2013 · Food science and biotechnology
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    ABSTRACT: Cancerous inhibitor of PP2A (CIP2A) stimulates proliferation of various cancer cells, and 17β-estradiol (E2) enhances the proliferation of breast cancer cells. E2 activates epidermal growth factor receptor (EGFR), stimulating the MEK1/2 and PI3K pathways, and CIP2A expression is increased by the MEK1/2-induced transcription factor ETS1. It is possible for E2 to increase CIP2A expression. This study examined whether E2 could increase the CIP2A expression and whether CIP2A is highly expressed in ER-positive breast cancer tissues. E2 increased CIP2A expression at the translational level in a c-MYC-independent manner in MCF-7 cells. E2-enhanced proliferation was impaired without CIP2A expression. E2-stimulated EGFR activated the MAPK and PI3K pathways, which converged to activate p70 S6 kinase (S6K). Phosphorylation at all three phosphorylation sites (S424/T421, T229, and T389) on S6K was required for the phosphorylation of eukaryotic initiation factor 4B (eIF4B), which was responsible for the increase in CIP2A translation. Furthermore, CIP2A expression was higher in ER-positive tissues than in ER-negative tissues. This manuscript is the first report to demonstrate that CIP2A is key factor of E2-enhanced proliferation and that estrogen regulates CIP2A expression by non-genomic action through EGFR.
    Preview · Article · Nov 2013 · Endocrine Related Cancer
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    Jung-Hoon Song · Mi Young Park · Hye Won Park · Hyung-Tae Lim
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    ABSTRACT: Homogeneous co-precipitation and hydrothermal treatment were used to prepare nano- and highly dispersed NiO/YSZ (yttria-stabilized zirconia) composite powders. Composite powders of size less than 100 nm were successfully prepared. This process did not require separate sintering of the YSZ and NiO to be used as the raw materials for solid oxide fuel cells. The performance of a cell fabricated using the new powders (max. power density ∼0.87 W/cm2) was higher than that of a cell fabricated using conventional powders (max. power density ∼0.73 W/cm2). Co-precipitation and hydrothermal treatment proved to be very effective processes for reducing cell production costs as well as improving cell performance.
    Full-text · Article · Jun 2013
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    ABSTRACT: Many approaches have been suggested as anti-tumor therapy for targeting insulin-like growth factor 1 receptor (IGF-1R), such as monoclonal antibodies and tyrosine kinase inhibitor. We introduced recombinant adenoviruses expressing antisense, dominant negative or short hairpin RNA to IGF-1R. Moreover, we demonstrated that histone deacetylase inhibitor (vorinostat) can increase the transduction efficiency of adenoviruses by increasing CAR-induced transduction and by enhancing the transcription of the adenoviral transgene. In the present study, we showed that the combination of ad-sh (short hairpin) IGF-1R with vorinostat leads to a synergistic enhancement of IGF-1R blockade. We measured the change in IGF-1R upon cotreatment with vorinostat and ad-shIGF-1R. Changes in transduction efficiency of ad-shIGF-1R were measured by fluorescent microscopy. Changes in apoptotic proportion and cell survival after the cotreatment were measured by the sub-G1 assay and cell counts. The effect of nuclear factor (NF)-κB activation was also measured by NF-κB p65 activation enzyme-linked immunosorbent assay. Drug interactions were analyzed upon cotreatment with ad-shIGF-1R, vorinostat and cisplatin. Combined treatment of ad-shIGF-1R and vorinostat synergistically suppressed the IGF-1R expression in lung cancer cell lines and also increased the transduction efficiency of ad-shIGF-1R. Ad-shIGF-1R and vorinostat cotreatment increased apoptotic cell death and synergistically suppressed cell growth compared to ad-shIGF-1R or vorinostat treatment alone. Vorinostat suppressed NF-κB activation, which was activated by ad-shIGF-1R. Moreover, triple combination of ad-shIGF-1R, vorinostat and cisplatin demonstrated synergistic cytotoxicity on lung cancer cells. Vorinostat enhanced the blocking capability of ad-shIGF-1R. The combined treatment of vorinostat and ad-sh-IGF-1R appears to have promising potential as a new therapeutic approach for lung cancer. Copyright
    No preview · Article · Mar 2013 · The Journal of Gene Medicine
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    ABSTRACT: Transformation of MDS into ALL during childhood is extremely rare. We report a rare case of an 8-yr-old girl who presented with refractory cytopenia of childhood (RCC) that transformed into ALL only 3 months after the diagnosis of childhood MDS. Although no cytogenetic abnormalities were observed in conventional karyotype and FISH analysis, we found several deletions on chromosomes 5q, 12q, 13q, and 22q. Partial homozygous deletion of the RB1 gene was observed on microarray analysis, with the bone marrow specimen diagnosed as ALL. This is the first case report of transformation of ALL from childhood MDS in Korea. We also compared the clinical, cytological, and cytogenetic features of 4 previously reported childhood MDS cases that transformed into ALL.
    Full-text · Article · Mar 2013 · Annals of Laboratory Medicine
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    ABSTRACT: One-third of patients who receive cardiac resynchronization therapy (CRT) are classified as nonresponders. Characteristics of responders to CRT have been studied in multiple clinical trials. Independent predictors of CRT response may be identified by studying a series of patients in routine clinical practice. One hundred twenty-five patients were examined retrospectively from a multidisciplinary CRT clinic program. Echocardiographic CRT response was defined as a decrease in left ventricular (LV) end-systolic volume of ≥15% and/or absolute increase of 5% in LV ejection fraction at the 6-month visit. There were 81 responders and 44 nonresponders. By univariate analyses, female sex, nonischemic cardiomyopathy etiology, baseline QRS duration, the presence of left bundle branch block (LBBB), and left ventricular end-diastolic volume (LVEDV) index predicted CRT response. However, multivariate analysis demonstrated that only QRS duration, LBBB, and LVEDV index were independent predictors (QRS width, odds ratio [OR]: 1.027, 95% confidence interval [CI]: 1.004–1.050, P = 0.023; LBBB, OR: 3.568, 95% CI: 1.284–9.910, P = 0.015; LVEDV index, OR: 0.970, 95% CI: 0.953–0.987, P = 0.001). Although female sex and nonischemic etiology were associated with an improved CRT response on univariate analyses, after adjusting for LV volumes they were not independent predictors. QRS width, LBBB, and LVEDV index are independent predictors for echocardiographic CRT response. Previously reported differences in CRT response for sex and cardiomyopathy etiology are associated with differences in baseline LV volumes in our clinical practice. Dr. Heist has received research grants (modest) from Biotronik, Boston Scientific, and St. Jude Medical; honoraria (modest) from Biotronik, Boston Scientific, Medtronic, Sorin, and St. Jude Medical; and consultant/advisory board positions (modest) from Boston Scientific, Sorin and St. Jude Medical. Dr. Singh has received research grants (significant) from Biotronik, Boston Scientific, Medtronic, and St. Jude Medical; and consultant/advisory board positions (modest) from Biosense Webster, Biotronik, Boston Scientific, CardioInsight, Medtronic, Sorin, St. Jude Medical, and Thoratec Inc. The statistical analysis was conducted with support from Harvard Catalyst. The Harvard Clinical and Translational Science Center (National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health Award UL1 RR 025758, and financial contributions from Harvard University and its affiliated academic healthcare centers). The authors have no other funding, financial relationships, or conflicts of interest to disclose.
    Full-text · Article · Dec 2012 · Clinical Cardiology
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    ABSTRACT: Patients with diabetes and heart failure (HF) have worse clinical outcomes compared to patients with HF without diabetes after cardiac resynchronization therapy (CRT). Patients with HF and diabetes represent a growing population at high risk for cardiovascular events and are increasingly treated with CRT. Although patients with diabetes and HF appear to benefit from CRT, their clinical outcomes are worse than those of patients without diabetes after CRT. The aim of this study was to identify clinical predictors that explain the differential hazard in patients with diabetes. We studied 442 patients (169 with diabetes) with systolic HF referred to the Massachusetts General Hospital CRT clinic from 2003 to 2010 to identify predictors of outcomes after CRT in patients with HF and diabetes. Patients with diabetes were more likely to have ischemic causes of HF than those without diabetes, but there was no difference in the left ventricular ejection fraction or HF classification at implantation. Patients with diabetes had poorer event-free survival (death or HF hospitalization) compared to those without diabetes (log-rank p = 0.04). The presence of diabetes was the most important independent predictor of differential outcomes in the entire population (hazard ratio 1.65, 95% confidence interval 1.10 to 2.51). Patients with diabetes receiving insulin therapy had poorer survival, whereas those not receiving insulin therapy had similar survival to patients without diabetes. Patients with peri-implantation glycosylated hemoglobin >7% had worse outcomes, whereas patients with glycosylated hemoglobin ≤7% had improved survival (hazard ratio 0.36, 95% confidence interval 0.15 to 0.86) equivalent to that of patients without diabetes. In conclusion, although the presence of diabetes, independent of other variables, increases the hazard of worse outcomes after CRT, there is additional risk conferred by insulin use and suboptimal peri-implantation glycemic control.
    Full-text · Article · May 2012 · The American journal of cardiology
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    ABSTRACT: A decade of research has established the role of cardiac resynchronization therapy (CRT) in medically refractory, moderate to severe systolic heart failure (HF) with intraventricular conduction delay. CRT is an electrical therapy instituted to reestablish ventricular synchronization in order to improve cardiac function and favorably modulate the neurohormonal system. CRT confers a mortality benefit, improved HF hospitalizations, and functional outcome in this population, but not all patients consistently demonstrate a positive CRT response. The nonresponder rate varies from 20% to 40%, depending on the defined response criteria. Efforts to improve response to CRT have focused on a number of fronts. Methods to optimize the correction of electrical and mechanical dyssynchrony, which is the primary target of CRT, has been the focus of research, in addition to improving patient selection and optimizing post-implant care. However, a major issue in dealing with improving nonresponse rates has been finding an accurate and generally accepted definition of "response" itself. The availability of a standard consensus definition of CRT response would enable the estimation of nonresponder burden accurately and permit the development of strategies to improve CRT response. In this review, we define various aspects of "response" to CRT and outline variability in the definition criteria and the problems with its inconsistencies. We describe clinical, laboratory, and pacing predictors that influence CRT response and outcome and how to optimize response.
    No preview · Article · Apr 2012 · Journal of Cardiovascular Translational Research
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    ABSTRACT: Here we report the cytogenetic and clinical manifestations observed in a patient with a rec(20)dup(20p)inv(20)(p11.2q13.3)mat. The patient was a full-term newborn girl with asymmetric intrauterine growth restriction and multiple congenital malformations, including a ventricular septal defect, pulmonary atresia, ambiguous genitalia, clinodactyly, and sacral dimpling. To our knowledge, this is the 4th report in the world and the 1st one in Korea of a patient with rec(20)dup(20p).
    Full-text · Article · Jan 2012 · Annals of Laboratory Medicine
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    ABSTRACT: The present study was performed to investigate antioxidant, anticancer, and antimicrobial activities of four Korean sweet potato variaties and to identify the changes in these biological activities under different cooking conditions. Total polyphenol content was 3.8-73.6 mg/g in 80% ethanol extracts of sweet potatoes. The polyphenol content was highest Sinjami variety (p < 0.05). Radical scavenging activity against DPPH and ABTS·+ was high in Sinjami (p < 0.05) and the ethanol extract from Sinjami also showed effective superoxide dismutase (SOD)-like activity, which decreased significantly by steaming and roasting (p < 0.05). Ethanol extracts from the four sweet potato variaties did not inhibit cancer cell growth in MCF-7 or HepG2 cells at concentrations of 1, 10, and 100 µg/mL. Of the investigated sweet potato variaties, only Sinjami exhibited strong antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium. The antimicrobial activity of Sinjami against E. coli, St. aureus, and S. typhimurium decreased following steaming and roasting (p < 0.05). These results indicate that the Sinjami Korean sweet potato had higher polyphenol content, radical scavenging activity, SOD-like activity, and antimicrobial activity than those of the other variaties and consuming raw Sinjami might be beneficial for maintenance of biological activities.
    Preview · Article · Jan 2012 · The Korean Journal of Nutrition
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    ABSTRACT: A substantial proportion of patients who meet the current guidelines for cardiac resynchronization therapy (CRT) fail to respond to this pacing modality. Although appropriate patient selection and left ventricular (LV) lead location have been ascribed as determinants of CRT response, the interaction among contractile reserve, dynamics of dyssynchrony, and lead location is not well understood. The present study prospectively evaluated the effect of contractile reserve and dobutamine-induced changes in LV synchrony, in relation to the LV lead location, as predictors of the response to CRT. In the present study, 31 patients were prospectively evaluated and underwent low-dose dobutamine echocardiography. The dobutamine-induced increase in ejection fraction (contractile reserve [CR]) was measured, and the most mechanically delayed segment was identified to classify patients into 2 groups. Group 1 had a CR of >20% and a LV lead position concordant with the mechanically delayed segment. Group 2 included the remaining patients (i.e., low CR, discordant LV lead position, or both). Patients in group 1 were significantly more likely to have an echocardiographic response at 6 months (80% of group 1 vs 29% of group 2, p = 0.018) and had an improved 2-year heart failure hospitalization-free survival rate (90% in group 1 vs 33% in group 2, p = 0.006). In conclusion, low-dose dobutamine echocardiography provides information that can help to predict responders to CRT. The response rates and heart failure hospitalization-free survival were improved in those patients with a CR >20% and an LV lead tip concordant with the most delayed mechanical segment.
    Preview · Article · May 2011 · The American journal of cardiology
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    ABSTRACT: The cancerous inhibitor of protein phosphatase 2A (CIP2A) increases the migration and metastasis of various cancer cells. Overexpression of CIP2A has been shown to increase the proliferation of MDA-MB-231 cells. We thus assessed whether CIP2A expression is associated with sensitivity to doxorubicin. MDA-MB-231 cells showed an increase in CIP2A expression after treatment with doxorubicin, while MCF-7 cells showed a decrease in CIP2A expression. The overexpression of CIP2A in MCF-7 cells overcame the inhibition of cell proliferation in response to doxorubicin treatment. CIP2A expression was not affected by wild-type or mutant p53. However, mutant p53 blocked doxorubicin-mediated CIP2A down-regulation in HCT116 cells. As a regulation mechanism of doxorubicin-mediated CIP2A expression, we showed that phosphorylated Akt was involved in the suppression of CIP2A expression.
    Full-text · Article · Mar 2011 · FEBS letters
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    Jong-Ho Lee · Sangyoon Lee · Mi Young Park · Heejoon Myung
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    ABSTRACT: In an effort to find chemicals inhibiting the enzymatic activity of the hepatitis C virus (HCV) NS5B polymerase, a series of thiobarbituric acid derivatives were selected from a library provided by Korea Research Institute of Chemical Technology and characterized. The selected compounds exhibited IC50 values ranging from 1.7 to 3.8 μM, and EC50 values ranging from 12.3 to 20.7 μM against NS5B polymerase of type 1b strain. They showed little effect against type 2a polymerase. One of the compounds, G05, was selected and further characterized. It inhibited the synthesis of RNA by recombinant HCV NS5B polymerase in a dose dependent manner. The CC50 value was 77 μM. The inhibition was in a noncompetitive manner with the substrate UTP. The compound did not inhibit the elongation step of RNA synthesis in a single-cycle processive polymerization assay. It inhibited the binding of NS5B polymerase to the template RNA in a dose-dependent manner.
    Preview · Article · Jan 2011 · Virology Journal
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    ABSTRACT: This study was conducted to examine the in vitro activity of antimicrobials against Campylobacter spp. isolates from chicken and human sources and the genetic interrelation among them. During 2004-2008, a total of 173 Campylobacter spp. isolated from chicken meats (60 domestic and 62 imported chicken meats) and humans (n = 51) were tested for susceptibility to nine antimicrobials. Of 173 isolates, 140 (80.9%) showed multidrug resistance (MDR) against three to eight antimicrobials. The most frequent pattern type was MDR to four antimicrobials: ciprofloxacin, nalidixic acid, ampicillin, and tetracycline. Over 52.6% (91/173) of the isolates tested were resistant to these four antibiotics simultaneously. Especially, two and five isolates originated from Korea and Brazil showed resistance against all antibiotics tested, except for florfenicol. Further, 95% (57/60) of the isolates originated from domestic chicken showed resistance to ciprofloxacin, the antimicrobial agent of choice for treatment of human campylobacteriosis. Genotypic characterization of all Campylobacter isolates performed by pulsed-field gel electrophoresis yielded 74 types among the 173 isolates. Isolates sharing the same or similar genetic clusters were detected in different countries at different times. The pulsed-field gel electrophoresis patterns of chicken-related isolates were closely related to those of isolates from humans with gastroenteritidis. The results of this study suggest that MDR Campylobacter spp. are widespread and that Campylobacter with similar genotypes are circulating both in humans and in chicken meat in Korea.
    No preview · Article · Nov 2010 · Foodborne Pathogens and Disease

Publication Stats

344 Citations
112.57 Total Impact Points

Institutions

  • 2015
    • Massachusetts General Hospital
      Boston, Massachusetts, United States
  • 2014-2015
    • Changwon National University
      창녕읍, Gyeongsangnam-do, South Korea
    • Hallym University
      Sŏul, Seoul, South Korea
  • 2008-2015
    • Sungkyunkwan University
      Sŏul, Seoul, South Korea
  • 2013
    • National Academy of Agricultural Science (South Korea)
      • Division of Agro-food Resources
      Sŏul, Seoul, South Korea
  • 2011-2013
    • Sookmyung Women's University
      Sŏul, Seoul, South Korea
    • Beth Israel Deaconess Medical Center
      Boston, Massachusetts, United States
  • 2009-2013
    • Seoul National University Bundang Hospital
      • Department of Medicine
      Sŏul, Seoul, South Korea
    • Seoul Medical Center
      Sŏul, Seoul, South Korea
  • 2008-2013
    • Pusan National University
      • Department of Laboratory Medicine
      Busan, Busan, South Korea
  • 2012
    • Harvard University
      Cambridge, Massachusetts, United States
  • 2004-2011
    • Hankuk University of Foreign Studies
      • Department of Bioscience and Biotechnology
      Sŏul, Seoul, South Korea
    • Korea University Medical Center
      Sŏul, Seoul, South Korea
  • 2010
    • Seoul National University
      Sŏul, Seoul, South Korea
    • National Veterinary Research Quarantine Service
      Sŏul, Seoul, South Korea
  • 2008-2009
    • Sejong General Hospital
      부천시, Gyeonggi-do, South Korea
  • 2007
    • MEDIPOST Biomedical Research Institute
      Sŏul, Seoul, South Korea