1,720,991 research outputs found
L'antibiotico-resistenza in ceppi di E. coli isolati da specie aviari e cunicole commerciali e selvatiche
Full text linkAntimicrobial-resistance is a public health problem world-wide and it is largely attributed to horizontal exchange of transferable genetic ele-ments such as plasmids carrying integrons (Sunde and Norstrom, 2006). The aim of this study was to define the antimicrobial-resistance phenotypes and to characterize class 1 and class 2 integrons in E. coli isolated both from commercial and wild birds and lagomorphs between 2006 and 2012 in Italy. The strains isolated form lagomorphs were also genotyped and screened for Plasmid-Mediated Quinolones Resistance (PMQR) genes and plasmids. Strains were examined for antimicrobial susceptibility by agar disk diffusion method. Class 1 and class 2 integrons were detected by real-time PCR and gene cassettes content identified by DNA sequencing. PMQR genes were screened by PCR and DNA sequencing. Clonal relatedness of the isolates from lagomorphs was assessed by Multilocus Sequence Typing (MLST). Plasmids were characterized by PCR-Based Replicon Typing (PBRT). Class 1 integrons were detected in multi-drug resistant E. coli both from commercial and wild birds and lagomorphs while class 2 integrons were found only in domestic avian species. Different gene cassettes were identified but the most common were combinations of aadA, sat and dfrA, codifying for aminoglycosides and trimethoprim resistance. Of the 172 E. coli isolates from lagomorphs, 12.2% (21/172) carried oqxAB, none other PMQR de-terminants. All but 3 oqxAB positive E. coli strains were recovered from farm rabbits and most of them were associated with the predominant CC17 and carried from 1 to 7 different plasmid types, such as IncF, IncHI1, IncI1, IncR, IncN, IncP, IncX1, IncY, and ColE. This study pro-vides new insights on the prevalence and dissemination of integrons and oqxAB in E. coli from farm and wild animals, suggesting that these species may be reservoir of these genetic determinants in Italy and thus a potential source of multi-drug resistant E. coli for human
Lethal septic shock after dental scaling in a healthy dog due to Ochrobactrum anthropi-contaminated propofol
No full textA 10-year-old, 6-kg male Yorkshire terrier dog was scheduled for routine dental cleaning. No significant
problem was observed either during anaesthesia, which was induced with propofol, or during recovery.
However, 2 hours after discharge, the dog’s owner returned to the clinic, complaining that the
animal was lethargic and had had bloody diarrhoea. On physical examination the dog was depressed,
dyspnoeic, tachycardic and hypoglycaemic. Despite supportive treatment, the dog deteriorated and
died within a few hours.
A presumed diagnosis of sepsis was confirmed by laboratory testing. Bacteriological and molecular
examinations of both premortem blood samples and the anaesthetic, highlighted the presence of
Ochrobactrum anthropi, an opportunistic pathogen usually associated with immunocompromised hosts
with indwelling medical devices. To the authors’ knowledge, this is the first case of sepsis in a healthy
dog due to contamination of an anaesthetic solution by O. anthropi, suggesting a potential role of this
microorganism as an emerging pathogen
Absence of class 1 and class 2 integrons among Campylobacter jejuni and Campylobacter coli isolated from poultry in Italy.
No full textThe paper reports on a study carried out in order to determine the presence of class 1 and 2 integrons in Campylobacter jejuni and Campylobacter coli isolated from intensively reared chickens and turkeys.
Despite the large consumption of chicken and turkey meat worldwide, the recognized role of poultry as reservoir of thermophilic campylobacters and the increasing of antimicrobial resistance in campylobacters, very few studies have been carried out to detect the presence of these genetic structures.
Although evidence of class 1 integron-carrying Campylobacter exists, no integrons were detected in our study. Therefore we can assume that the horizontal gene transfer mediated by integrons may not represent a significant mechanism for the dissemination of antimicrobial resistance determinants in Campylobacter organism
Salmonella spp. prevalence and antimicrobial resistance pattern (phenotypic profiles and presence of genetic AMR determinants) of serotypes isolated from pet reptiles in Northern Italy
No full textA total of 324 cloacal swabs were collected from reptiles kept at pet animals import centres (48 samples), pet shops (103 samples), zoological park (71 samples) and private owners (102 samples) located in Northern Italy. Samples were collected from healthy snakes (n = 147), lizards (n = 85) and turtles (n = 92). Isolation, typization of Salmonella spp. and the evaluation of sensitivity to different classes of antimicrobial drugs (16 antimicrobial agents) were performed using the classical bacteriological and serological procedures and the agar disc diffusion method (Kirby-Bauer). Isolates showing particular phenotypic AMR profiles were subjected to further molecular characterizations, especially the detection by PCR and sequencing of genetic elements involved in the diffusion and dissemination of AMR among Enterobacteriaceae (i.e. class 1 and class 2 integrons and AMR genes codifying for the resistance to tetracycline, aminoglycosides, beta-lactams, phenicol compounds etc...).
Salmonella spp. was isolated from 205 (63.3 %) cloacal swabs. Prevalence data were different for snakes (76.9 %) and lizards (74.1 %) compared to turtles (31.5 %). Serotyping showed the presence of S. enterica subsp. enterica (53.2 %), S. enterica subsp. diarizonae (29.8 %), S. enterica subsp. houtenae (10.2 %), S. enterica subsp. salamae (6.3 %) and S. enterica subsp. arizonae (0.5 %).
Out of 205 isolates, only 12 (5.8 %) showed full susceptibility to all the drugs tested and 95 (46.3 %) strains showed multidrug-resistance (i. e. resistance to three or more antimicrobials). Out of the 205 isolates, only 1 carried class 1 integron and only few strains showed a correlation between the phenotypic and genotypic patterns of AMR. These data underlines the importance to carry out further genetic investigations to better understand the genetic bases and mechanisms of the diffusion of AMR among these strains
Phylodynamic analysis of porcine reproductive and respiratory syndrome virus (PRRSV) in Italy: Action of selective pressures and interactions between different clades
No full textPorcine reproductive and respiratory syndrome (PRRS) is the most relevant and challenging infectious disease to affect swine breeding. Despite this, several aspects of the virus' evolution and virus-host interaction are still poorly understood and largely based on knowledge obtained through in vitro or in vivo experimental infections. Due to peculiar experimental conditions, our understanding is often contradictory and difficult to infer with respect to actual field conditions. Our phylodynamic study, based on ORF5 sequences of 141 samples collected in Italy from 1993 to 2012, explores different aspects of PRRSV epidemiology, evolution, and virus-host interaction. Two major clades, belonging to Type 1 subtype 1, were demonstrated to co-circulate while harboring a relevant intra- and inter-clade genetic diversity. Most Recent Common Ancestor (MRCA), evolution rates, and population dynamics were estimated using a serial coalescent-based approach, and different demographic histories were reconstructed for the two clades. Analysis of selective pressure revealed that sites subjected to diversifying selection were mainly located in the region of glycoprotein 5 (GP5) exposed to the host environment. Similarly, the vast majority of strains were highly glycosylated, confirming the proposed protective role of the glycan shield against the humoral immune response. Overall, our study reports both interactions among the viral populations as well as between virus and host, and their relevance in shaping viral evolution: different population dynamics over time seem to reflect a competition between clades. Some evidence argues in favor of the role of immune pressure in affecting GP5 evolution, including frequent changes in the region exposed to the host immune response, and preserving glycosylation profiles that can hamper humoral immunity
Prevalence and antimicrobial-resistance characterization of vancomycin resistant enterococci (VRE) strains in healthy household dogs in Italy
Full text linkWild birds as carriers of antimicrobial-resistant and ESBL-producing Enterobacteriaceae
Full text linkInternational trades, local spread and viral evolution: The case of porcine circovirus type 2 (PCV2) strains heterogeneity in Italy
Full text linkPorcine circovirus type 2 is one of the most widespread and economically relevant infections of swine. Four genotypes have been recognized, but currently, only three (PCV2a, PCV2b and PCV2d) are effectively circulating. The widespread livestock trade and rapid viral evolution have contributed to determining the high heterogeneity of PCV2 and the dispersal of potentially more virulent strains. Italian swine farming and the related processing industry are relevant in the national economy. Despite the noteworthy losses associated with direct and control measure costs, no data are currently available on the molecular epidemiology of PCV2 in Italy. Our study, which was intended to fill this gap, considered 75 completed genome PCV2 sequences, which were obtained from samples collected from the highly densely populated area of Northern Italy between 2007 and 2014. Phylogenetic analysis and comparison with reference sequences demonstrated the co-circulation, with different prevalences, of PCV2a, PCV2b and PCV2d within the national borders, with PCV2b being the most prevalent. Recombination between different genotypes was also proven to be frequent. Phylogeographic analysis demonstrated that the marked variability of Italian PCV2 strains can be attributable to multiple introduction events. The comparison of the phylogenetic analysis results, the location of different haplotypes and the international commercial routs of live pigs allow the speculation of several links as well as the role of Italy as both an importer and exporter of PCV2 haplotypes, mainly from and to European and Asian countries. A similarly intricate contact network was demonstrated within national borders, with different haplotypes being detected in the same province and different provinces harbouring the same haplotype. Overall, this paper represents the first description of PCV2 in Italy and demonstrates that the high variability of circulating Italian strains is due to multiple introduction events, wide circulation within national boundaries and rapid viral evolution
Antimicrobial resistance in Escherichia coli isolates from domestic and wild rabbits in Italy.
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