scholarly journals Prevalence and characterization of Escherichia coli in the Kelantan River and its adjacent coastal waters

2020 ◽  
Vol 20 (3) ◽  
pp. 930-942
Author(s):  
Chui Wei Bong ◽  
Siong Kiat Chai ◽  
Lay Ching Chai ◽  
Ai Jun Wang ◽  
Choon Weng Lee
Keyword(s):  
Escherichia Coli ◽  
Coastal Waters ◽  
Membrane Filtration ◽  
Sea Water ◽  
Phylogenetic Group ◽  
Animal Origin ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Colony Forming Units ◽  
Phylogenetic Grouping

Abstract The presence of Escherichia coli in river and sea water may cause different levels of infections and constitutes a risk to public health. In this study, water samples were collected from 15 sites along the Kelantan River, estuaries and its adjacent coastal waters to investigate the prevalence and diversity of E. coli. A membrane filtration technique was used to enumerate E. coli and phylogenetic grouping was performed using triplex polymerase chain reaction. E. coli abundance ranged from 3.1 × 10 to 1.6 × 105 colony forming units 100 mL−1, and total suspended solids correlated significantly with E. coli abundance (r2 = 0.165, p < 0.001) and rainfall (r2 = 0.342, p < 0.001). Phylogenetic group B1 and A (59.4%) were the most prevalent, whereas groups B2 and D were least abundant. The higher abundance of phylogenetic group D at upstream sites of the Kelantan River suggested fecal contamination mainly of animal origin. Canonical-correlation analysis showed phylogenetic group B2, and phylogenetic groups A and D were greater in waters with higher inorganic nutrients (e.g. NH4, NO2 and NO3), whereas phylogenetic group B1 appeared to have better salinity tolerance between phylogenetic groups.

scholarly journals Phylogenetic Grouping and Virulence Potential of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains in Cattle

2012 ◽  
Vol 78 (13) ◽  
pp. 4677-4682 ◽  
Author(s):  
Charlotte Valat ◽  
Frédéric Auvray ◽  
Karine Forest ◽  
Véronique Métayer ◽  
Emilie Gay ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Determinants ◽  
Phylogenetic Groups ◽  
Content Type ◽  
E Coli ◽  
Extended Spectrum ◽  
Specific Distribution ◽  
Extended Spectrum Beta Lactamases ◽  
Phylogenetic Grouping ◽  
Almost All

ABSTRACTIn line with recent reports of extended-spectrum beta-lactamases (ESBLs) inEscherichia coliisolates of highly virulent serotypes, such as O104:H4, we investigated the distribution of phylogroups (A, B1, B2, D) and virulence factor (VF)-encoding genes in 204 ESBL-producingE. coliisolates from diarrheic cattle. ESBL genes, VFs, and phylogroups were identified by PCR and a commercial DNA array (Alere, France). ESBL genes belonged mostly to the CTX-M-1 (65.7%) and CTX-M-9 (27.0%) groups, whereas those of the CTX-M-2 and TEM groups were much less represented (3.9% and 3.4%, respectively). One ESBL isolate wasstx1andeaepositive and belonged to a major enterohemorrhagicE. coli(EHEC) serotype (O111:H8). Two other isolates wereeaepositive butstxnegative; one of these had serotype O26:H11. ESBL isolates belonged mainly to phylogroup A (55.4%) and, to lesser extents, to phylogroups D (25.5%) and B1 (15.6%), whereas B2 strains were quasi-absent (1/204). The number of VFs was significantly higher in phylogroup B1 than in phylogroups A (P= 0.04) and D (P= 0.02). Almost all of the VFs detected were found in CTX-M-1 isolates, whereas only 64.3% and 33.3% of them were found in CTX-M-9 and CTX-M-2 isolates, respectively. These results indicated that the widespread dissemination of theblaCTX-Mgenes within theE. colipopulation from cattle still spared the subpopulation of EHEC/Shiga-toxigenicE. coli(STEC) isolates. In contrast to other reports on non-ESBL-producing isolates from domestic animals, B1 was not the main phylogroup identified. However, B1 was found to be the most virulent phylogroup, suggesting host-specific distribution of virulence determinants among phylogenetic groups.

Escherichia coli Strains Isolated from Retail Meat Products: Evaluation of Biofilm Formation Ability, Antibiotic Resistance, and Phylogenetic Group Analysis

2020 ◽  
Vol 83 (2) ◽  
pp. 233-240
Author(s):  
ELENA BARILLI ◽  
ALICE VISMARRA ◽  
VIVIANA FRASCOLLA ◽  
MARTINA REGA ◽  
CRISTINA BACCI
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Multidrug Resistance ◽  
Health Risk ◽  
Phylogenetic Group ◽  
Animal Origin ◽  
Potential Health ◽  
Potential Health Risk ◽  
E Coli ◽  
Retail Meat

ABSTRACT Escherichia coli is a ubiquitous organism capable of forming a biofilm. This is an important virulence factor and is critical in certain diseases and in the development of antibiotic resistance, which is increased by biofilm synthesis. In the present study, the potential health risk associated with handling and consumption of foods of animal origin contaminated with E. coli–producing biofilm was evaluated. We analyzed the ability of 182 E. coli strains isolated from pork, poultry, and beef, purchased in three different supermarkets in the area of the “Italian Food Valley” (Parma, northern Italy), to form biofilms. Positive strains were also tested for the presence of 12 biofilm-associated genes. Moreover, the 182 E. coli were characterized for antibiotic resistance, presence of multidrug resistance, extended-spectrum β-lactamase strains, and phylogenetic diversity through PCR. Twenty-five percent of the isolates produced biofilm. The majority showed weak adherence, five were moderate, and three were strong producers. E. coli with a strong adherence capability (three of three) harbored eight biofilm-associated genes, while weak and moderate producers harbored only five (frequencies ranging from 80 to 100%). Multidrug resistance was observed in 20 biofilm-producing E. coli, and 15 of these belonged to phylogenetic group D. Among nonbiofilm producers, the percentage of strains belonging to phylogenetic groups B2 and D was approximately 40%, highlighting a potential health risk for consumers and people handling contaminated products. The present study underlines the importance of monitoring the prevalence and characteristics of E. coli contaminating retail meat in relation to the potential virulence highlighted here. HIGHLIGHTS

scholarly journals Phylogenetic groups and antimicrobial susceptibility patterns of uropathogenic Escherichia coli clinical isolates from patients at Mulago National Referral Hospital, Kampala, Uganda

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 1828 ◽  
Author(s):  
Paul Katongole ◽  
Daniel Bulwadda Kisawuzi ◽  
Henry Kyobe Bbosa ◽  
David Patrick Kateete ◽  
Christine Florence Najjuka
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Susceptibility ◽  
Phylogenetic Group ◽  
Diffusion Method ◽  
Clinical Microbiology Laboratory ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Pcr Method ◽  
Tract Infections ◽  
Susceptibility Patterns

Introduction: Uropathogenic Escherichia coli (UPEC) remains the most common cause of urinary tract infections (UTIs). They account for over 80-90% of all community-acquired and 30-50% of all hospital-acquired UTIs. E. coli strains have been found to belong to evolutionary origins known as phylogenetic groups. In 2013, Clermont classified E. coli strains into eight phylogenetic groups using the quadruplex PCR method. The aim of this study was to identify the phylogenetic groups of UPEC strains in Uganda using Clermont’s quadruplex PCR method and to assess their antibiotic susceptibility patterns in Uganda. Methods: In this cross-sectional study, 140 stored uropathogenic E. coli isolates from the Clinical Microbiology Laboratory, Department of Medical Microbiology, College of Health Sciences Makerere University were subjected to phylogenetic typing by a quadruplex PCR method. Antimicrobial susceptibility testing was performed by disk diffusion method according to Clinical & Laboratory Standards Institute (CLSI) guidelines. Phenotypic detection of extended-spectrum beta-lactamase, AmpC and carbapenemases was done according to CLSI guidelines and Laboratory SOPs. Results: Phylogenetic group B2 (40%) was the most predominant, followed by A (6.23%), clade I and II (5%), D and E (each 2.14%), B1 (1.43%) and F and C (each 0.71%). The most common resistant antibiotic was trimethoprim-sulphamethoxazole (90.71%) and the least was imipenem (1.43%). In total, 73.57% of isolates were multi-drug resistant (MDR). Antibiotic resistance was mainly detected in phylogenetic group B2 (54%). Conclusions: Our findings showed the high prevalence of MDR E. coli isolates, with the dominance of phylogenetic group B2. About 9% of E. coli isolates belonged to the newly described phylogroups C, E, F, and clade I and II.

scholarly journals Detection of virulence genes, phylogenetic group and antibiotic resistance of uropathogenic Escherichia coli in Mongolia

2017 ◽  
Vol 11 (01) ◽  
pp. 51-57 ◽  
Author(s):  
Yandag Munkhdelger ◽  
Nyamaa Gunregjav ◽  
Altantsetseg Dorjpurev ◽  
Nishi Juniichiro ◽  
Jav Sarantuya
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Virulence Genes ◽  
Wide Spectrum ◽  
Iron Acquisition ◽  
Uropathogenic Escherichia Coli ◽  
Phylogenetic Group ◽  
Diffusion Method ◽  
Phylogenetic Groups ◽  
E Coli

Introduction: The severity of urinary tract infection (UTI) produced by uropathogenic Escherichia coli (UPEC) is due to the expression of a wide spectrum of virulence genes. E. coli strains were divided into four phylogenetic groups (A, B1, B2 and D) based on their virulence genes. The present study aimed to assess the relationship between virulence genes, phylogenetic groups, and antibiotic resistance of UPEC. Methodology: A total of 148 E. coli were tested for antimicrobial resistance against 10 drugs using the disk diffusion method. The isolates were screened by polymerase chain reaction (PCR) for detection of virulence genes and categorized into the four major phylogenetic groups. Results: Phylogenetic group B2 was predominant (33.8%), followed by D (28.4%), A (19.6), and B1 (18.2%). A higher prevalence of fimH (89.9%), fyuA (70.3%), traT (66.2%), iutA (62.2%), kpsMTII (58.8%), and aer (56.1%) genes were found in UPEC, indicating a putative role of adhesins, iron acquisition systems, and protectins that are main cause of UTIs. The most common antibiotic resistance was to cephalotin (85.1%), ampicillin (78.4%) and the least to nitrofurantoin (5.4%) and imipenem (2%). In total, 93.9% of isolates were multidrug resistant (MDR). Conclusions: This study showed that group B2 and D were the predominant phylogenetic groups and virulence-associated genes were mostly distributed in these groups. The virulence genes encoding components of adhesins, iron acquisition systems, and protectins were highly prevalent among antibiotic-resistant UPEC. Although the majority of strains are MDR, nitrofurantoin is the drug of choice for treatment of UTI patients in Ulaanbaatar.

scholarly journals Characterization of commensal Escherichia coli isolates from slaughtered sheep in Mexico

2021 ◽  
Vol 15 (11) ◽  
pp. 1755-1760
Author(s):  
Jorge Acosta-Dibarrat ◽  
Edgar Enriquez-Gómez ◽  
Martín Talavera-Rojas ◽  
Edgardo Soriano-Vargas ◽  
Armando Navarro ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Multidrug Resistant ◽  
Phylogenetic Group ◽  
Phylogenetic Groups ◽  
E Coli ◽  
New Information ◽  
Antimicrobial Resistance Genes ◽  
Uremic Syndrome

Introduction: Commensal Escherichia coli is defined as bacteria without known virulence factors that could be playing a specific role in some diseases; however, they could be responsible to disseminate antimicrobial resistance genes to other microorganisms. This study aimed to characterize the commensal E. coli isolates obtained from slaughtered sheep in the central region of Mexico. Methodology: Isolates were classified as commensal E. coli when distinctive genes related to diarrheagenic pathotypes (stx1, stx2, eae, bfp, LT, stp, ipaH, and aggR) were discarded by PCR. Identification of serotype, phylogenetic group, and antimicrobial resistance was also performed. Results: A total of 41 isolates were characterized. The phylogenetic groups found were B1 in 37 isolates (90.2%), A in 2 (4.8%), and 1 isolate (2.4%) for C and D groups. Serotypes associated with diarrhea in humans (O104:H2 and O154:NM) and hemolytic uremic syndrome (O8:NM) were detected. Thirty-three isolates (80%) were resistant to ceftazidime, 23 (56%), to tetracycline 8 (19.5%) to ampicillin, and 1 to amikacin. Six isolates (14.6%) were multidrug-resistant. Conclusions: This study provides new information about commensal E. coli in slaughtered sheep, high percentages of resistance to antibiotics, and different profiles of antimicrobial resistance were found, their dissemination constitute a risk factor towards the consuming population.

Phylogenetic association of fluoroquinolone and cephalosporin resistance of D-O1-ST648 Escherichia coli carrying bla CMY-2 from faecal samples of dogs in Japan

2014 ◽  
Vol 63 (2) ◽  
pp. 263-270 ◽  
Author(s):  
Toyotaka Sato ◽  
Shin-ichi Yokota ◽  
Torahiko Okubo ◽  
Masaru Usui ◽  
Nobuhiro Fujii ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Phylogenetic Group ◽  
Clinical Isolates ◽  
Dominant Group ◽  
E Coli ◽  
Faecal Samples ◽  
Phylogenetic Grouping ◽  
Cephalosporin Resistance ◽  
Group D

This study aimed to investigate the genetic association between fluoroquinolone (FQ) and/or cephalosporin (CEP) resistance in Escherichia coli isolates from dogs, and the risk to human health. We characterized E. coli clinical isolates, derived from faecal samples of dogs attending veterinary hospitals, using phylogenetic grouping, determination of virulence factor (VF) prevalence, multilocus sequence typing (MLST) and O serotyping. The D group was the dominant phylogenetic group among strains resistant to FQ and/or CEP. In contrast, the dominant group among susceptible strains was group B2. Group D strains showed a significantly higher prevalence of VFs than strains belonging to groups A and B1, and were resistant to significantly more antimicrobials than group B2 strains. The phylogenetic distribution of FQ–CEP-resistant E. coli groups (FQ–CEPRECs) and FQ-resistant groups was significantly correlated (r = 0.98), but FQ–CEPRECs and CEP-resistant E. coli groups were not correlated (r = 0.58). Data from PFGE, O serotype and MLST analyses indicated that the majority of FQ-resistant strains derived from a particular lineage of phylogenetic group D: serotype O1 and sequence type (ST) 648. Some D-O1-ST648 strains carried bla CMY-2, showed multidrug resistance and possessed a higher prevalence of the VFs kspMT, ompT and PAI compared with other group D strains. Our data indicate that the emergence of FQ-CEP-resistant E. coli is based primarily on FQ-resistant E. coli. Moreover, as strains of the D-O1-ST648 lineage have been found in clinical isolates derived from humans at a relatively high frequency, our findings indicate that the spreading of D-O1-ST648 strains may cause serious difficulties in both veterinary and human clinical fields in the future.

scholarly journals Determination of the frequency of β-lactamase genes (bla SHV, bla TEM, bla CTX-M) and phylogenetic groups among ESBL-producing uropathogenic Escherichia coli isolated from outpatients

2020 ◽  
Vol 44 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Shiva Mirkalantari ◽  
Faramarz Masjedian ◽  
Gholamreza Irajian ◽  
Emmanuel Edwar Siddig ◽  
Azam Fattahi
Keyword(s):  
Escherichia Coli ◽  
Resistance Pattern ◽  
Phylogenetic Groups ◽  
Accurate Identification ◽  
E Coli ◽  
Resistance Patterns ◽  
Phylogenetic Grouping ◽  
Pcr Method ◽  
Tract Infections

Abstract Background Escherichia coli accounts for 70–95% of community-acquired urinary tract infections (UTIs). Recently, there has been an increase in the prevalence of extended-spectrum β-lactamase (ESBL) in the community which required an accurate identification for better management. Therefore, the current study was performed to determine the antimicrobial resistance pattern, investigate ESBL phenotypes and genotypes (blaCTX-M, bla TEM and bla SHV genes) and determine the phylogenetic groups among ESBL-positive isolates from outpatients. Methods One hundred and eighty-three positive urine samples were collected from 4450 outpatient clinic attendees. Antibiotic susceptibility was determined and ESBL phenotype screening was carried out using disk diffusion agar and combination disk techniques, respectively. The assessment of the presence of the blaCTX-M, bla TEM and blaSHV genes and phylogenetic grouping were performed using the polymerase chain reaction (PCR) method. Results Out of 183 E. coli isolates, 59 (32.2%) showed a positive ESBL phenotype. The prevalence of ESBL-producing E. coli was higher in males (57.4%). Fifty-seven of the ESBL-producing strains carried at least one of the β-lactamase genes (bla CTX-M, bla TEM, bla SHV). Phylotyping of multi-drug resistant isolates indicated that the isolates belonged to B2, A and D phylogroups. Analysis of resistance patterns among these phylogroups revealed that 74.4%, 55.3% and 29.7% of the isolates in the B2 group were resistant to trimethoprim-sulfamethoxazole, ciprofloxacin and gentamicin, respectively. Most of the strains in the phylogroup B2 carried the bla CTX-M gene. Conclusions All the ESBL-producing isolates were placed in one of the four phylogenetic groups. The presence of CTX-M and resistance to quinolones were more frequent in B2 strains than in non-B2 strains.

Characterization of multidrug-resistant Escherichia coli isolated from extraintestinal clinical infections in animals

2010 ◽  
Vol 59 (5) ◽  
pp. 592-598 ◽  
Author(s):  
Justine S. Gibson ◽  
Rowland N. Cobbold ◽  
Darren J. Trott
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Susceptibility ◽  
Animal Species ◽  
Antimicrobial Agents ◽  
Multidrug Resistant ◽  
Phylogenetic Group ◽  
Phylogenetic Groups ◽  
Diagnostic Laboratory ◽  
E Coli

Multidrug-resistant (MDR) Escherichia coli causes extraintestinal infections in both humans and animals. This study aimed to determine whether MDR E. coli isolates cultured from extraintestinal infections in several animal species were clonal and crossed host-species boundaries, as suggested by initial characterization of a subset of canine and human isolates, or whether they represented a diverse group of host-specific strains. Isolates were obtained either from The University of Queensland Veterinary Diagnostic Laboratory or from an independent diagnostic laboratory between October 1999 and December 2007. Ninety-six MDR E. coli isolates cultured from extraintestinal clinical infections in 55 animals comprising dogs (n=45), cats (n=5), horses (n=4) and a koala (n=1) were analysed by phylogenetic grouping, antimicrobial susceptibility testing and PFGE. The isolates were cultured from the urinary tract (n=61), reproductive tract (n=11), wounds (n=11), surgical site infections (n=4) and other sites (n=9). Isolates from the same E. coli phylogenetic group with 100 % PFGE similarity and the same antimicrobial susceptibility pattern were considered to be repeat clones and excluded from further analysis. Three of the four E. coli phylogenetic groups (A, n=19; B1, n=8; and D, n=49) were represented. Analysis of PFGE similarity identified clusters of related phylogenetic group A isolates [clonal group (CG) 1] and group D isolates (CG2 and CG3), with the remainder of the isolates demonstrating diversity. The majority of CG2 isolates contained a plasmid-borne AmpC β-lactamase, imparting resistance to cefoxitin and third-generation cephalosporins, and were obtained between 2000 and 2003. CG3 isolates were sensitive to these antimicrobial agents and appeared to replace CG2 isolates as the dominant clones from 2003 to 2007. Apart from several canine and feline isolates that demonstrated clonality, PFGE profiles tended to be divergent across species. Whilst MDR E. coli isolates from extraintestinal infections in different animal species are diverse, some dominant CGs may persist over several years.

scholarly journals Phylogenetic Group of Escherichia coli Isolates from Broilers in Brazilian Poultry Slaughterhouse

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Fernanda M. Coura ◽  
Soraia A. Diniz ◽  
Marcos X. Silva ◽  
Thiago L. M. Arcebismo ◽  
Silvia Minharro ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Respiratory Tract ◽  
Phylogenetic Group ◽  
Phylogenetic Groups ◽  
E Coli

The aim of the study was to determine the phylogenetic groups of E. coli strains isolated from seemingly healthy broiler and broiler condemned suspected of colibacillosis in a Brazilian slaughterhouse. Samples from respiratory tract and edible giblets (liver and heart) of broilers with and without macroscopic lesions of colibacillosis were collected at slaughter. There were 84 strains isolated from broilers condemned of which 11 were obtained from swabs of the heart, 7 from the liver, and 66 from the respiratory tract. Of the 53 E. coli strains isolated from broilers not condemned, 5 were isolated from the heart, 4 from the liver, and 44 from the respiratory tract. E coli strains were tested via PCR for phylogenetic groups A, B1, B2, C, D, E, and F. Phylogroups A and B1 were the most common phylogroups of E. coli obtained from healthy and sick-appearing broiler carcasses. The results of the study showed that phylogroups B2 and E were associated with the heart samples and phylogroup A was associated with respiratory tract samples, phylogroup B1 with not condemned carcass, and phylogroup D with liver samples.

scholarly journals Phylogenetic Analysis and Prevalence of Urosepsis Strains of Escherichia coli Bearing Pathogenicity Island-Like Domains

2002 ◽  
Vol 70 (6) ◽  
pp. 3216-3226 ◽  
Author(s):  
Martine Bingen-Bidois ◽  
Olivier Clermont ◽  
Stéphane Bonacorsi ◽  
Mustapha Terki ◽  
Naïma Brahimi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Phylogenetic Analysis ◽  
Genetic Linkage ◽  
Virulence Genes ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Genetic Elements ◽  
Physical Linkage ◽  
Phylogenetic Grouping ◽  
Compromised Patients

ABSTRACT We characterized 100 Escherichia coli urosepsis isolates from adult patients according to host compromise status by means of ribotyping, PCR phylogenetic grouping, and PCR detection of papG alleles and the virulence-related genes sfa/foc, fyuA, irp-2, aer, hly, cnf-1 and hra. We also tested these strains for copies of pap and hly and their direct physical linkage with other virulence genes in an attempt to look for pathogenicity islands (PAIs) described for the archetypal uropathogenic strains J96, CFT073, and 536. Most of the isolates belonged to E. coli phylogenetic groups B2 and D and bore papG allele II, aer, and fyuA/irp-2. papG allele II-bearing strains were more common in noncompromised patients, while papG allele-negative strains were significantly more frequent in compromised patients. Fifteen ribotypes were identified. The three archetypal strains harbored different ribotypes, and only one-third of our urosepsis strains were genetically related to one of the archetypal strains. Three and 18 strains harbored three and two copies of pap, respectively, and 5 strains harbored two copies of hly. papGIII was physically linked to hly, cnf-1, and hra (reported to be PAI IIJ96-like genetic elements) in 14% of the strains. The PAI IIJ96-like domain was inserted within pheR tRNA in 11 strains and near leuX tRNA in 3 strains. Moreover, the colocalized genes cnf-1, hra, and hly were physically linked to papGII in four strains and to no pap gene in three strains. papGII and hly (reported to be PAI ICFT073-like genetic elements) were physically linked in 16 strains, pointing to a PAI ICFT073-like domain. Three strains contained both a PAI IIJ96-like domain and a PAI ICFTO73-like domain. Forty-two strains harbored papGII but not hly, in keeping with the presence of a PAI IICFT073-like domain. Only one strain harbored a PAI I536-like domain (hly only), and none harbored a PAI IJ96-like domain (papGI plus hly) or a PAI II536-like domain (papGIII plus hly). This study provides new data on the prevalence and variability of physical genetic linkage between pap and certain virulence-associated genes that are consistent with their colocalization on archetypal PAIs.

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