scholarly journals Arcobacter in Lake Erie Beach Waters: an Emerging Gastrointestinal Pathogen Linked with Human-Associated Fecal Contamination

2012 ◽  
Vol 78 (16) ◽  
pp. 5511-5519 ◽  
Author(s):  
Cheonghoon Lee ◽  
Senyo Agidi ◽  
Jason W. Marion ◽  
Jiyoung Lee
Keyword(s):  
Lake Erie ◽  
Fecal Contamination ◽  
Tetracycline Resistance ◽  
Gastrointestinal Diseases ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
23S Rrna Gene ◽  
East And West ◽  
Pcr Targeting

ABSTRACTThe genusArcobacterhas been associated with human illness and fecal contamination by humans and animals. To better characterize the health risk posed by this emerging waterborne pathogen, we investigated the occurrence ofArcobacterspp. in Lake Erie beach waters. During the summer of 2010, water samples were collected 35 times from the Euclid, Villa Angela, and Headlands (East and West) beaches, located along Ohio's Lake Erie coast. After sample concentration,Arcobacterwas quantified by real-time PCR targeting theArcobacter23S rRNA gene. Other fecal genetic markers (Bacteroides16S rRNA gene [HuBac],Escherichia coli uidAgene,Enterococcus23S rRNA gene, and tetracycline resistance genes) were also assessed.Arcobacterwas detected frequently at all beaches, and both the occurrence and densities ofArcobacterspp. were higher at the Euclid and Villa Angela beaches (with higher levels of fecal contamination) than at the East and West Headlands beaches. TheArcobacterdensity in Lake Erie beach water was significantly correlated with the human-specific fecal marker HuBac according to Spearman's correlation analysis (r= 0.592;P< 0.001). Phylogenetic analysis demonstrated that most of the identifiedArcobactersequences were closely related toArcobacter cryaerophilus, which is known to cause gastrointestinal diseases in humans. Since human-pathogenicArcobacterspp. are linked to human-associated fecal sources, it is important to identify and manage the human-associated contamination sources for the prevention ofArcobacter-associated public health risks at Lake Erie beaches.

scholarly journals Evidence for Multidrug Resistance in NonpathogenicMycoplasmaSpecies Isolated from South African Poultry

2018 ◽  
Vol 84 (21) ◽  
Author(s):  
Amanda Beylefeld ◽  
Pamela Wambulawaye ◽  
Dauda Garba Bwala ◽  
Johannes Jacobus Gouws ◽  
Obed Mooki Lukhele ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
South African ◽  
Macrolide Resistance ◽  
Quinolone Resistance ◽  
23S Rrna ◽  
Clear Correlation ◽  
Rrna Gene ◽  
Poultry Production ◽  
Content Type ◽  
23S Rrna Gene

ABSTRACTOne hundred seventy-eight mycoplasma strains isolated from South African poultry flocks between 2003 and 2015 were identified by full-genome sequencing and phylogenetic analysis of the 16S rRNA gene and were classified as follows:Mycoplasma gallisepticum(25%),M. gallinarum(25%),M. gallinaceum, (23%),M. pullorum(14%),M. synoviae(10%), andM. iners(3%), as well as oneAcheoplasma laidlawiistrain (1%). MIC testing was performed on the axenic samples, and numerous strains of each species were resistant to either chlortetracycline or tylosin or both, with variable sensitivity to enrofloxacin. The strains of all species tested remained sensitive to tiamulin, except for oneM. gallinaceumsample that demonstrated intermediate sensitivity. The mutation of A to G at position 2059 (A2059G) in the 23S rRNA gene, which is associated with macrolide resistance, was found in the South AfricanM. gallisepticumandM. synoviaestrains, as well as a clear correlation between macrolide resistance inM. gallinarumandM. gallinaceumand mutations G354A and G748A in the L4 ribosomal protein and 23S rRNA gene, respectively. No correlation between resistance and point mutations in the genes studied could be found forM. pullorum. Only a few strains were resistant to enrofloxacin, apart from oneM. synoviaestrain with point mutation D420N, which has been associated with quinolone resistance, and no other known markers for quinolone resistance were found in this study. Proportionally more antimicrobial-resistant strains were detected inM. gallinaceum,M. gallinarum, andM. pullorumthan inM. gallisepticumandM. synoviae. Of concern, threeM. gallinaceumstrains showed multidrug resistance to chlortetracycline, tylosin, and oxytetracycline.IMPORTANCENonpathogenic poultryMycoplasmaspecies are often overlooked due to their lesser impact on poultry health and production compared to the OIE-listed pathogenic strainsM. gallisepticumandM. synoviae. The use of antimicrobials as in-feed growth promoters and for the control of mycoplasmosis is common in poultry production across the world. Here, we provide evidence that certain nonpathogenicMycoplasmaspecies are acquiring multidrug resistance traits. This would have significant implications if these species, for which no vaccines are applied, are able to transfer their antibiotic resistance genes to other mycoplasmas and bacteria that may enter the human food chain.

Streptococcus dentisani sp. nov., a novel member of the mitis group

2014 ◽  
Vol 64 (Pt_1) ◽  
pp. 60-65 ◽  
Author(s):  
Anny Camelo-Castillo ◽  
Alfonso Benítez-Páez ◽  
Pedro Belda-Ferre ◽  
Raúl Cabrera-Rubio ◽  
Alex Mira
Keyword(s):  
Type Species ◽  
Spherical Shape ◽  
Culture Collection ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type ◽  
23S Rrna Gene ◽  
Tooth Surfaces ◽  
Streptococcal Species

Genomic, taxonomic and biochemical studies were performed on two strains of α-haemolytic streptococci that showed them to be clustered with major members of the Streptococcus mitis group. These Gram-stain-positive strains were isolated from tooth surfaces of caries-free humans and showed the classical spherical shape of streptococcal species growing in chains. Sequence analysis from concatenated 16S and 23S rRNA gene and sodA genes showed that these strains belonged to the mitis group, but both of them clustered into a new phylogenetic branch. The genomes of these two isolates were sequenced, and whole-genome average nucleotide identity (ANI) demonstrated that these strains significantly differed from any streptococcal species, showing ANI values under 91 % even when compared with the phylogenetically closest species such as Streptococcus oralis and S. mitis . Biochemically, the two isolates also showed distinct metabolic features relative to closely related species, like α-galactosidase activity. From the results of the present study, the name Streptococcus dentisani sp. nov. is proposed to accommodate these novel strains, which have been deposited in open collections at the Spanish type Culture Collection (CECT) and Leibniz Institute DSMZ–German Collection of Microorganisms and Cell Cultures (DSMZ), being respectively identified as Streptococcus dentisani Str. 7746 ( = CECT 8313 = DSM 27089) and Streptococcus dentisani Str. 7747T ( = CECT 8312T = DSM 27088T).

scholarly journals Sensitive Quantification of Clostridium difficile Cells by Reverse Transcription-Quantitative PCR Targeting rRNA Molecules

2012 ◽  
Vol 78 (15) ◽  
pp. 5111-5118 ◽  
Author(s):  
Kazunori Matsuda ◽  
Hirokazu Tsuji ◽  
Takashi Asahara ◽  
Takuya Takahashi ◽  
Hiroyuki Kubota ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Quantitative Pcr ◽  
Reverse Transcription ◽  
Care Facility ◽  
23S Rrna ◽  
Rrna Gene ◽  
Carriage Rate ◽  
Content Type ◽  
Reverse Transcription Quantitative Pcr ◽  
Pcr Targeting

ABSTRACTWe established a sensitive and accurate quantification system forClostridium difficilein human intestines, based on rRNA-targeted reverse transcription-quantitative PCR (RT-qPCR). We newly developed a species-specific primer set forC. difficiletargeting 23S rRNA gene sequences. Both the vegetative cells and the spores ofC. difficilein human feces were quantified by RT-qPCR, with a lower detection limit of 102.4cells/g of feces. In an analysis of the feces of residents (n= 83; age, 85 ± 8 years) and staff (n= 19; age, 36 ± 10 years) at a care facility for the elderly,C. difficilewas detected by RT-qPCR in 43% of the residents (average count, log104.0 ± 2.0 cells/g of feces) and 16% of the staff (average count, log102.2 ± 0.1 cells/g of feces); these rates were far higher than those detected by qPCR (residents, 19%; staff, 0%) or selective cultivation (residents, 18%; staff, 5%). Another analysis of healthy adults (n= 63; age, 41 ± 11 years) also revealed the significant carriage rate ofC. difficilein the intestines (detection rate, 13%; average count, log104.9 ± 1.2 cells/g of feces). From these results, it was suggested that rRNA-targeted RT-qPCR should be an effective tool for analyzing population levels ofC. difficilein the human intestine.

Molecular mechanisms of macrolide and fluoroquinolone resistance among Korean isolates of Mycoplasma genitalium over a period of five years 2014–2019

2021 ◽  
Vol 70 (11) ◽  
Author(s):  
Yumi Seo ◽  
Heeyoon Park ◽  
Gilho Lee
Keyword(s):  
Genetic Diversity ◽  
Antimicrobial Resistance ◽  
Type Species ◽  
Mycoplasma Genitalium ◽  
Quinolone Resistance ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type ◽  
23S Rrna Gene

Antimicrobial resistance in Mycoplasma genitalium has become a global issue, and certain groups have a higher probability of acquiring resistant strains. Little is known about the genetic diversity and characteristics of the antimicrobial resistance-determining sites (ARDSs) of M. genitalium in the Korean population. Therefore, we examined the genetic diversity of the ARDSs of M. genitalium-positive urogenital samples obtained from Korean females (G1) and males (G2) visiting primary care clinics and DNA samples from referred males (G3) with persistent urethritis. From 2014 to 2019, 54 patients from G1, 86 patients from G2, and 68 patients from G3 were included in the study. Sanger sequencing was performed on the 2058/2059 sites in the 23S rRNA gene and quinolone resistance-determining regions (QRDRs) of M. genitalium . The rates of mutation in G1, G2, and G3 were 1.85, 5.81, and 48.53 %, respectively, for A2059G in the 23S rRNA gene (P<0.001); 1.85, 0, and 17.78 %, respectively, for M95R or I in gyrA (P<0.001); 0, 0, and 31.11 %, respectively, for D99N or G in gyrA (P<0.001); and 7.41, 16.28, and 30 %, respectively, for S83R or N or I in parC (P=0.015). A2059G significantly increased the risk of mutations at the gyrA95, gyrA99, and parC83 sites (all P<0.01). In conclusion, although the genetic diversity of the ARDSs of M. genitalium was variable among the groups, it was generally lower in isolates with macrolide resistance and higher in isolates with quinolone resistance in Korea compared with the isolates in other countries. The G3 group demonstrated increased genetic diversity at the A2059G, gyrA95, gyrA99, and parC83 sites.

scholarly journals Molecular Typing and Macrolide Resistance Analyses ofTreponema pallidumin Heterosexuals and Men Who Have Sex with Men in Japan, 2017

2018 ◽  
Vol 57 (1) ◽  
Author(s):  
Mizue Kanai ◽  
Yuzo Arima ◽  
Shingo Nishiki ◽  
Ken Shimuta ◽  
Ichiro Itoda ◽  
...  
Keyword(s):  
Molecular Typing ◽  
Treponema Pallidum ◽  
Macrolide Resistance ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
Heterosexual Women ◽  
23S Rrna Gene ◽  
Strain Type ◽  
Sex With Men

ABSTRACTIn recent years, syphilis notifications have increased dramatically in Japan. We carried out molecular typing and macrolide resistance analyses ofTreponema pallidumsubsp.pallidumsamples collected from patients at four clinics and a hospital in Tokyo and Osaka prefectures in 2017. The macrolide resistant strain type 14d/f (SS14-like clade) was found in significantly more cases of syphilis among heterosexuals than in those among men who have sex with men (MSM); i.e., 79% (31/39) of the strains from heterosexuals were 14d/f compared to 37% (7/19) of those from MSM (odds ratio [OR], 6.6; 95% confidence interval [CI], 1.7 to 26.7;P = 0.002). In addition, 83% (50/60) of the strains were identified as macrolide resistant with an A2058G mutation in the 23S rRNA gene; 90% (35/39) of the strains from heterosexuals were macrolide resistant compared to 58% (11/19) of those from MSM. The odds of having the resistant mutation were considerably higher in the former (OR, 6.4; 95% CI, 1.3 to 33.5;P = 0.02). Heterosexual women and heterosexual men showed similar distributions, and the association remained the same when restricted to men. The strain type distribution and the prevalence of macrolide resistance differed substantially between syphilis strains from heterosexual cases and from MSM cases, suggesting distinct epidemiologic profiles for the two communities and providing important insight into the dynamics of syphilis in Japan.

scholarly journals Mutational and Transcriptomic Changes Involved in the Development of Macrolide Resistance in Campylobacter jejuni

2012 ◽  
Vol 57 (3) ◽  
pp. 1369-1378 ◽  
Author(s):  
Haihong Hao ◽  
Zonghui Yuan ◽  
Zhangqi Shen ◽  
Jing Han ◽  
Orhan Sahin ◽  
...  
Keyword(s):  
Campylobacter Jejuni ◽  
Dna Microarray ◽  
Ribosomal Proteins ◽  
Macrolide Resistance ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
23S Rrna Gene ◽  
Resistant Mutants ◽  
Antibiotic Efflux

ABSTRACTMacrolide antibiotics are important for clinical treatment of infections caused byCampylobacter jejuni. Development of resistance to this class of antibiotics inCampylobacteris a complex process, and the dynamic molecular changes involved in this process remain poorly defined. Multiple lineages of macrolide-resistant mutants were selected by stepwise exposure ofC. jejunito escalating doses of erythromycin or tylosin. Mutations in target genes were determined by DNA sequencing, and the dynamic changes in the expression of antibiotic efflux transporters and the transcriptome ofC. jejuniwere examined by real-time reverse transcription-PCR, immunoblotting, and DNA microarray analysis. Multiple types of mutations in ribosomal proteins L4 and L22 occurred early during stepwise selection. On the contrary, the mutations in the 23S rRNA gene, mediating high resistance to macrolides, were observed only in the late-stage mutants. Upregulation of antibiotic efflux genes was observed in the intermediately resistant mutants, and the magnitude of upregulation declined with the occurrence of mutations in the 23S rRNA gene. DNA microarray analysis revealed the differential expression of 265 genes, most of which occurred in the intermediate mutant, including the upregulation of genes encoding ribosomal proteins and the downregulation of genes involved in energy metabolism and motility. These results indicate (i) that mutations in L4 and L22 along with temporal overexpression of antibiotic efflux genes precede and may facilitate the development of high-level macrolide resistance and (ii) that the development of macrolide resistance affects the pathways important for physiology and metabolism inC. jejuni, providing an explanation for the reduced fitness of macrolide-resistantCampylobacter.

scholarly journals Utility of Sequencing theerm(41) Gene in Isolates of Mycobacterium abscessus subsp. abscessus with Low and Intermediate Clarithromycin MICs

2015 ◽  
Vol 53 (4) ◽  
pp. 1211-1215 ◽  
Author(s):  
Barbara A. Brown-Elliott ◽  
Sruthi Vasireddy ◽  
Ravikiran Vasireddy ◽  
Elena Iakhiaeva ◽  
Susan T. Howard ◽  
...  
Keyword(s):  
Nucleotide Substitution ◽  
Gene Mutations ◽  
Mycobacterium Abscessus ◽  
Macrolide Resistance ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
23S Rrna Gene ◽  
Content Sequencing

Theerm(41) gene confers inducible macrolide resistance inMycobacterium abscessussubsp.abscessus, calling into question the usefulness of macrolides for treatingM. abscessussubsp.abscessusinfections. With an extended incubation (14 days), isolates with MICs of ≥8 μg/ml are considered macrolide resistant by current CLSI guidelines. Our goals were to determine the incidence of macrolide susceptibility in U.S. isolates, the validity of currently accepted MIC breakpoints, and theerm(41) sequences associated with susceptibility. Of 349 isolates (excluding those with 23S rRNA gene mutations), 85 (24%) had clarithromycin MICs of ≤8 μg/ml. Sequencing of theerm(41) genes from these isolates, as well as from isolates with MICs of ≥16 μg/ml, including ATCC 19977T, revealed 10 sequevars. The sequence in ATCC 19977Twas designated sequevar (type) 1; most macrolide-resistant isolates were of this type. Seven sequevars contained isolates with MICs of >16 μg/ml. The T28C substitution inerm(41), previously associated with macrolide susceptibility, was identified in 62 isolates (18%) comprising three sequevars, with MICs of ≤2 (80%), 4 (10%), and 8 (10%) μg/ml. No other nucleotide substitution was associated with macrolide susceptibility. We recommend that clarithromycin susceptibility breakpoints forM. abscessussubsp.abscessusbe changed from ≤2 to ≤4 μg/ml and that isolates with an MIC of 8 μg/ml have repeat MIC testing orermsequencing performed. Our studies suggest that macrolides are useful for treating approximately 20% of U.S. isolates ofM. abscessussubsp.abscessus. Sequencing of theermgene ofM. abscessussubsp.abscessuswill predict inducible macrolide susceptibility.

scholarly journals Macrolide-Resistant Mycoplasma pneumoniae in Adults in Zhejiang, China

2014 ◽  
Vol 59 (2) ◽  
pp. 1048-1051 ◽  
Author(s):  
Zibo Zhou ◽  
Xiangzhi Li ◽  
Xiaojian Chen ◽  
Fangjun Luo ◽  
Changwang Pan ◽  
...  
Keyword(s):  
Mycoplasma Pneumoniae ◽  
Rflp Analysis ◽  
Zhejiang Province ◽  
23S Rrna ◽  
Rrna Gene ◽  
Type I ◽  
Content Type ◽  
23S Rrna Gene ◽  
Resistant Strains ◽  
Domain V

ABSTRACTMycoplasma pneumoniaeis a major pathogen causing community-acquired pneumoniae (CAP), which is generally treated with macrolides. In recent years, however, although macrolide-resistantM. pneumoniaehas been reported frequently, particularly in China, very little is known about the prevalence of macrolide-resistantM. pneumoniaeinfection in adults. In this study, we survey the macrolide-resistantM. pneumoniaein adults in Zhejiang province and characterize the mechanisms of resistance to macrolide. Six hundred fifty throat swab samples were collected from adult patients with CAP from January 2012 to August 2014. These samples were assayed by nested PCR and then cultivated forM. pneumoniae. All isolates were sequenced to determine the mutation in domain V of the 23S rRNA gene. The activities of 10 antibiotics against macrolide-resistantM. pneumoniaeisolates were also investigatedin vitro. Moreover, restriction fragment length polymorphism (RFLP) analysis of the amplified P1 gene was used to type 50 resistant strains. One hundred percent (71/71) ofM. pneumoniaestrains isolated from adults with CAP were resistant to erythromycin (MIC = 128 to >256 μg/ml), clarithromycin (MIC = 128 to >256 μg/ml), and azithromycin (MIC = 32 to >64 μg/ml). Furthermore, all macrolide-resistantM. pneumoniaestrains identified had an A2063G mutation in domain V of the 23S rRNA gene. Forty-six resistant strains (92.0%) were classified into type I strain on the basis of P1 gene PCR-RFLP analysis. According to these findings, it is suggested that macrolide-resistantM. pneumoniaeinfection is very prevalence among adults in Zhejiang province. Thus, there is necessary to perform the epidemiological monitoring of macrolide-resistantM. pneumoniaein the future.

scholarly journals More Complications Occur in Macrolide-Resistant than in Macrolide-Sensitive Mycoplasma pneumoniae Pneumonia

2013 ◽  
Vol 58 (2) ◽  
pp. 1034-1038 ◽  
Author(s):  
Yunlian Zhou ◽  
Yuanyuan Zhang ◽  
Yuanjian Sheng ◽  
Li Zhang ◽  
Zheng Shen ◽  
...  
Keyword(s):  
Mycoplasma Pneumoniae ◽  
Point Mutations ◽  
Clinical Manifestations ◽  
23S Rrna ◽  
Rrna Gene ◽  
Clinical Issue ◽  
Content Type ◽  
23S Rrna Gene ◽  
The Relationship ◽  
Resistant Genotypes

ABSTRACTWe sought to understand the situation of macrolide-resistant genotypes ofMycoplasma pneumoniae, and analyze the relationship between macrolide-resistant genotypes and clinical manifestations ofMycoplasma pneumoniaepneumonia (MPP). Full-length sequencing of the 23S rRNA gene ofM. pneumoniaewas performed in 235 nasopharyngeal aspirates (NPAs) from children with MPP. We also retrospectively compared the clinical characteristics of macrolide-resistant (MR)M. pneumoniaeinfections and macrolide-sensitive (MS)M. pneumoniaeinfections. A total of 206 patients had point mutations in theM. pneumoniae23S rRNA gene, and these patients are referred to as MR patients. The remaining 29 patients without point mutations are referred to as MS patients. Among 206 MR patients, 199 (96.6%) had A2063G mutations, 6 had A2063T mutations, and the remaining patients had an A2064G mutation. Among the clinical manifestations, we found that the median fever durations were 8 days (range, 0 to 42 days) and 6 days (0 to 14 days) (P< 0.01), the median hospitalization durations were 8 days (2 to 45 days) and 6 days (3 to 16 days) (P< 0.01), and the median fever durations after macrolide therapy were 5 days (0 to 42 days) and 3 days (0 to 10 days) (P< 0.01), respectively, in the MR and MS groups. We also found that the incidence of extrapulmonary complications in the MR group was significantly higher than that in the MS group (P< 0.05). Moreover, the radiological findings were more serious in the MR group than in the MS group (P< 0.05). The increasing prevalence of MRM. pneumoniaehas become a significant clinical issue in the pediatric patients, which may lead to more extrapulmonary complications and severe clinical features and radiological manifestations.

scholarly journals Trends towards Lower Antimicrobial Susceptibility and Characterization of Acquired Resistance among Clinical Isolates of Brachyspira hyodysenteriae in Spain

2011 ◽  
Vol 55 (7) ◽  
pp. 3330-3337 ◽  
Author(s):  
Álvaro Hidalgo ◽  
Ana Carvajal ◽  
Birte Vester ◽  
Märit Pringle ◽  
Germán Naharro ◽  
...  
Keyword(s):  
Antimicrobial Susceptibility ◽  
Molecular Mechanisms ◽  
Tandem Repeats ◽  
Point Mutations ◽  
Clinical Isolates ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
Brachyspira Hyodysenteriae ◽  
23S Rrna Gene

ABSTRACTThe antimicrobial susceptibility of clinical isolates ofBrachyspira hyodysenteriaein Spain was monitored, and the underlying molecular mechanisms of resistance were investigated. MICs of tylosin, tiamulin, valnemulin, lincomycin, and tylvalosin were determined for 87B. hyodysenteriaeisolates recovered from 2008 to 2009 by broth dilution. Domain V of the 23S rRNA gene and the ribosomal protein L3 gene were sequenced in 20 isolates for which the tiamulin MIC was ≥4 μg/ml, presenting decreased susceptibility, and in 18 tiamulin-susceptible isolates (MIC ≤ 0.125 μg/ml), and all isolates were typed by multiple-locus variable-number tandem repeats analysis. A comparison with antimicrobial susceptibility data from 2000 to 2007 showed an increase in pleuromutilin resistance over time, doubling the number of isolates with decreased susceptibility to tiamulin. No alteration in susceptibility was detected for lincomycin, and the MIC of tylosin remained high (MIC50> 128 μg/ml). The decreased susceptibility to tylosin and lincomycin can be explained by mutations at position A2058 of the 23S rRNA gene (Escherichia colinumbering). A2058T was the predominant mutation, but A2058G also was found together with a change of the neighboring base pair at positions 2057 to 2611. The role of additional point mutations in the vicinity of the peptidyl transferase center and mutations in the L3 at amino acids 148 and 149 and their possible involvement in antimicrobial susceptibility are considered. An association between G2032A and high levels of tiamulin and lincomycin MICs was found, suggesting an increasing importance of this mutation in antimicrobial resistance of clinical isolates ofB. hyodysenteriae.

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