1.Detection of Escherichia coli O157 and Escherichia coli O157:H7 by the immunomagnetic separation technique and stx1 and stx2 genes by multiplex PCR in slaughtered cattle in Samsun Province, Turkey.
Journal of Veterinary Science 2010;11(4):321-326
This study was conducted to investigate the presence of Escherichia (E.) coli O157 and E. coli O157:H7 and stx1 and stx2 genes on cattle carcasses and in rectal samples collected from Samsun Province of Turkey. A total of 200 samples collected from cattle carcasses and the rectal contents of 100 slaughtered cattle from two commercial abattoirs were tested using the immunomagnetic separation technique and multiplex PCR methods. E. coli O157 and E. coli O157:H7 were detected in 52 of the 200 samples (26%) tested. Of the positive samples, 49 were E. coli O157 and three were E. coli O157:H7. The E. coli O157 strain was isolated from 24 carcasses and 25 rectal samples, while E. coli O157:H7 was isolated from two carcasses and one rectal sample. Of the 49 samples positive for E. coli O157, 32 were from the rectal and carcass samples of the same animal, while two E. coli O157:H7 isolates were obtained from rectal swabs and carcasses of the same animal. The stx1 and stx2 genes were both detected in 35 E. coli O157 isolates and one E. coli O157:H7 isolate, but the stx2 gene was only detected alone in two E. coli O157 isolates. Overall, 16 carcasses tested positive for E. coli O157 and one carcass tested positive for E. coli O157:H7 based on both carcass and rectal samples. Overall, the results of this study indicate that cattle carcasses pose a potential risk to human health due to contamination by E. coli O157 and E. coli O157:H7 in the feces.
Abattoirs
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Animals
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Cattle
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Escherichia coli O157/*genetics/isolation & purification
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*Immunomagnetic Separation
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Meat/microbiology
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*Polymerase Chain Reaction
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Rectum/microbiology
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Shiga Toxin 1/*genetics
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Shiga Toxin 2/*genetics
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Turkey
3.Molecular typing of Shiga-toxin producing Escherichia coli O157:H7 isolated in China with pulsed field gel electrophresis.
Bo PANG ; Huaiqi JING ; Han ZHENG ; Hui SUN ; Ailan ZHAO ; Jianguo XU
Chinese Journal of Epidemiology 2002;23(2):123-126
OBJECTIVETo type and group the Shiga-toxin producing Escherichia coli O157:H7 strains isolated recent years in China to understand the epidemiological features caused by the pathogen.
METHODSPulsed field gel electrophoresis of large restriction fragments of bacterial chromosomal DNA was used.
RESULTSThe 51 isolates of E. coli O157:H7 collected in recent years in China could be divided into 8 Pulsed Field Gel Electrophoresis (PFGE) types based on the size and number of restriction fragments and patterns, that were digested by XbaI. Strains isolated from Ningxia province showed only two types- PFGE1 and PFGE2. Strains isolated in Xuzhou of Jiangsu province had 6 PFGE types. Isolates identified between 1986 - 1988 belonged to PFGE7. Strains isolated from patients in 1999 - 2000 were PFGE5 and PFGE3. Strains isolated from stool samples of domestic animal, food and vegetable were PFGE3 - 6, of which the predominant type was PFGE5. All of the 5 strains isolated from patients with diarrhea and hemolytic uremic syndrome (HUS) belonged to PFGE type 5, which was the dominant type of the isolates from stool samples of domestic animal and samples of food and vegetable contaminated.
CONCLUSIONData suggested that the cluster patients with diarrhea and HUS might have been related to the pathogens from domestic animas and contaminated food or vegetables. The distribution of PFGE types also varied in different provinces of China.
Electrophoresis, Gel, Pulsed-Field ; Escherichia coli O157 ; classification ; genetics ; pathogenicity ; Genotype ; Humans ; Shiga Toxin ; biosynthesis
4.Hemolytic uremic syndrome.
Li-Yan YE ; Jun-Jing HUANG ; Cheng-Feng WANG
Chinese Journal of Contemporary Pediatrics 2006;8(6):531-534
5.Predictors of Success of Selective Laser Trabeculoplasty Adjusted for Intraocular Pressure Variations
Jun Seok LEE ; Chong Eun LEE ; Sam SEO ; Kyoo Won LEE
Journal of the Korean Ophthalmological Society 2018;59(12):1166-1172
PURPOSE: To investigate the efficacy, and identify predictors of success of selective laser trabeculoplasty (SLT) in open-angle glaucoma (OAG) patients after adjusting for intraocular pressure (IOP) changes in the untreated fellow eye. METHODS: This retrospective chart review included 52 eyes of 52 OAG patients who underwent SLT in one eye and were followed-up for at least 1 year after the procedure. The IOP was measured before the treatment, at 1, 2, and 3 months posttreatment, and every 3 months thereafter. To account for the possible influence of IOP fluctuations on laser outcomes, post-laser IOP values of the treated eye of each patient were also analyzed, after adjusting for IOP changes in the untreated fellow eye. Success was defined as an IOP decrease ≥20% of the pretreatment IOP. The success rate was determined based on Kaplan-Meier survival analysis and factors predictive of success were analyzed using the Cox proportional hazard model. RESULTS: The mean pretreatment IOP was 23.17 ± 6.96 mmHg. The mean IOP reduction was 5.59 ± 4.78 mmHg (29.7%) and the success rate was 65.4% at 1 year. The adjusted mean IOP reduction was 4.70 ± 4.67 mmHg (23.9%) and the adjusted success rate was 53.9%. Pretreatment IOP was associated with SLT success; the higher the pretreatment IOP, the greater the post-laser IOP reduction (p = 0.025). Age and mean deviation index did not show a significant association with SLT success (p = 0.066 and p = 0.464, respectively). CONCLUSIONS: SLT is a safe and effective alternative method of IOP reduction in OAG patients. Herein, pretreatment IOP was the only factor significantly associated with SLT success. IOP fluctuations of the untreated eye should be considered for a better understanding of the impact of treatment.
Glaucoma, Open-Angle
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Humans
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Intraocular Pressure
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Methods
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Proportional Hazards Models
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Retrospective Studies
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Shiga Toxin 1
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Trabeculectomy
7.Comparison of Detection of Escherichia coli O157 Between Culture After Acid Treatment and Polymerase Chain Reaction After Enrichment.
The Korean Journal of Laboratory Medicine 2002;22(5):331-335
BACKGROUND: The Polymerase Chain Reaction (PCR) for the Shiga toxin has been widely used for diagnosis of Shiga toxin-producing Escherichia coli (STEC) infection including Escherichia coli O157 (O157) instead of using a culture. However, bacteriological isolation must be followed for final diagnosis. Our study was aimed to compare the detection limit between the culture after the acid treatment and the PCR after enrichment. METHODS: The standard strain of O157 was cultured, diluted and mixed with the stool of normal adult in order to make a final concentration of the 10(1)-10(5) colony forming unit (CFU)/g of stool. Each concentration of samples was enriched in a trypticase soy broth for 6 hours at 42degrees C and treated with acid to suppress normal flora. Then it was streaked on cefixime-tellurite-sorbitol MacConkey (CT-SMAC) agar evenly and cultured for 18 hours at 37degrees C. The same concentrations of bacterial suspension in the stool were enriched in a Luria-Bertani (LB) broth overnight at 37degrees C. The centrifuged pellets from 1 mL of each concentration of the samples were boiled and DNA was extracted using the resin method and PCR was performed to amplify stx2. RESULTS: The detection limit for the culture after acid treatment was 10(3) CFU/g of the stool and that for PCR after enrichment was 101 CFU/g of the stool. CONCLUSIONS: Culture after acid treatment for O157 would be an effective method for isolation of O157 from a patient's stool. However, this method is less sensitive than the PCR after enrichment as far as detection limit is concerned. A combination of both methods would be an effective method for detecting O157 from patient stools.
Adult
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Agar
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Diagnosis
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DNA
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Escherichia coli O157*
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Escherichia coli*
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Escherichia*
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Humans
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Limit of Detection
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Polymerase Chain Reaction*
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Shiga Toxin
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Shiga-Toxigenic Escherichia coli
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Stem Cells
8.Pathogenic and phylogenetic characteristics of non-O157 Shiga toxin-producing Escherichia coli isolates from retail meats in South Korea
June Bong LEE ; Dalmuri HAN ; Hyung Tae LEE ; Seon Mi WI ; Jeong Hoon PARK ; Jung Woo JO ; Young Jae CHO ; Tae Wook HAHN ; Sunjin LEE ; Byunghak KANG ; Hyo Sun KWAK ; Jonghyun KIM ; Jang Won YOON
Journal of Veterinary Science 2018;19(2):251-259
Herein, we report the pathogenic and phylogenetic characteristics of seven Shiga toxin (Stx)-producing Escherichia coli (STEC) isolates from 434 retail meats collected in Korea during 2006 to 2012. The experimental analyses revealed that all isolates (i) were identified as non-O157 STEC, including O91:H14 (3 isolates), O121:H10 (2 isolates), O91:H21 (1 isolate), and O18:H20 (1 isolate), (ii) carried diverse Stx subtype genes (stx₁, stx(2c), stx(2e), or stx₁ + stx(2b)) whose expression levels varied strain by strain, and (iii) lacked the locus of enterocyte effacement (LEE) pathogenicity island, a major virulence factor of STEC, but they possessed one or more alternative virulence genes encoding cytotoxins (Cdt and SubAB) and/or adhesins (Saa, Iha, and EcpA). Notably, a significant heterogeneity in glutamate-induced acid resistance was observed among the STEC isolates (p < 0.05). In addition, phylogenetic analyses demonstrated that all three STEC O91:H14 isolates were categorized into sequence type (ST) 33, of which two beef isolates were identical in their pulsotypes. Similar results were observed with two O121:H10 pork isolates (ST641; 88.2% similarity). Interestingly, 96.0% of the 100 human STEC isolates collected in Korea during 2003 to 2014 were serotyped as O91:H14, and the ST33 lineage was confirmed in approximately 72.2% (13/18 isolates) of human STEC O91:H14 isolates from diarrheal patients.
Cytotoxins
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Enterocytes
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Escherichia coli
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Genomic Islands
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Humans
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Korea
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Meat
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Population Characteristics
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Red Meat
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Shiga Toxin
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Shiga-Toxigenic Escherichia coli
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Virulence
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Virulence Factors
9.Molecular epidemiology of sequence type 33 of Shiga toxin-producing Escherichia coli O91:H14 isolates from human patients and retail meats in Korea
Jun Bong LEE ; Se Kye KIM ; Seon Mi WI ; Young Jae CHO ; Tae Wook HAHN ; Jae yon YU ; Sungsun KIM ; Sahyun HONG ; Jonghyun KIM ; Jang Won YOON
Journal of Veterinary Science 2019;20(1):87-90
Sequence type (ST) 33 of Shiga toxin-producing Escherichia coli (STEC) strain O91:H14 has been proposed as a potential domestic clone of STEC in Korea because of its high prevalence among human patients with mild diarrhea or asymptomatic carriers. Herein, the clonal diversity of 17 STEC O91:H14 isolates of ST33 during 2003 to 2014 was analyzed by pulsed-field gel electrophoresis, including 14 isolates from human patients and 3 from retail meats. Their virulence characteristics, acid resistance, and antimicrobial susceptibility were also determined. Our results showed that all isolates were clustered mainly into three different pulsotypes and were likely low pathogenic without antimicrobial resistance.
Clone Cells
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Diarrhea
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Electrophoresis, Gel, Pulsed-Field
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Escherichia coli
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Humans
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Korea
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Meat
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Molecular Epidemiology
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Prevalence
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Shiga Toxin
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Shiga-Toxigenic Escherichia coli
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Virulence
10.Cause of Enterohemorrhagic Escherichia coli Infection in Ulju County, Korea.
Geun Ryang BAE ; Sang Won LEE ; Byung Guk YANG ; Bok Kwon LEE ; Jae Gu PARK ; Byeong Hun HWANG ; Hyun Sul LIM
Korean Journal of Preventive Medicine 2003;36(1):77-84
OBJECTIVES: Two related cases of Hemolytic-Uremic Syndrome (HUS) were reported to the Korea National Institute of Health in May, 2001. Shiga toxin 2 genes were detected in both stool samples. We suspected an enterohemorrhagic Escherichia coli (EHEC) infection as the cause of the HUS, and conducted an investigation to find the source of the infection and its route of transmission. METHODS: We performed case investigations on these two related HUS cases, and obtained interviews and rectal swabs form the family members and other close contacts. Additionally, we performed rectal swabs on the cattle raised by the household of the index patient. RESULTS: We found a 20 month old index patient and a 6 year-old cousin had developed HUS, where there had been a 2 day history of contact with the index, and bacteriological examinations for these two patients revealed, indistinguishably, the same E. coli O171. The grandmother of the index patient was found to be asymptomatic, but E. coli O26 was isolated. We also found a probable case in the mother of the cousin. She reported a history of contact with the index, and developed bloody diarrhea of 3 days duration. The test results for the cattle revealed E. coli O26 in one cow, and E. coli O26 and O55 in another. E. coli O26, which was isolated in both cows and the grandmother of the index, were indistinguishably the same. CONCLUSIONS: We found that the E. coli O26 in the grandmother had originated from the cows, and that the E. coli O171 found in the index patient had been transmitted to the cousin through person-to-person contact.
Animals
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Cattle
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Diarrhea
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Enterohemorrhagic Escherichia coli*
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Family Characteristics
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Grandparents
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Hemolytic-Uremic Syndrome
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Humans
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Korea*
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Mothers
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Shiga Toxin 2
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Zoonoses