Search results for "Serotype"

Acquisition of Class C β-Lactamase PAC-1 by Sequence Type 644 Strains of Pseudomonas aeruginosa

2019

Four sequence type 664 (ST664) (serotype O:5) strains of Pseudomonas aeruginosa that were highly resistant to antibiotics, including ceftolozane-tazobactam and ceftazidime-avibactam, but were susceptible to colistin were found to harbor the gene encoding the rare class C β-lactamase PAC-1 on a chromosomally located Tn 1721 -like transposon. The bla PAC-1 gene was associated with the 16S rRNA methylase determinant rmtF2 , which confers pan-aminoglycoside resistance.

Heterogeneity and temporal dynamics of evolution of G1 human rotaviruses in a settled population.

2006

ABSTRACT A rotavirus sample collection from 19 consecutive years was used to investigate the heterogeneity and the dynamics of evolution of G1 rotavirus strains in a geographically defined population. Phylogenetic analysis of the VP7 gene sequences of G1P[8] human rotavirus strains showed the circulation of a heterogeneous population comprising three lineages and seven sublineages. Increases in the circulation of G1 rotaviruses were apparently associated with the introduction of novel G1 strains that exhibited multiple amino acid changes in antigenic regions involved in rotavirus neutralization compared to the strains circulating in the previous years. The emergence and/or introduction of G…

Molecular characterization of the genotype G9 human rotavirus strains recovered in Palermo, Italy, during the winter of 1999-2000

2004

Among the known human rotavirus serotypes, types G1–G4 are ubiquitous and account for >80% of global human rotavirus strains. Since 1994 an increase in reports of G9 serotype isolates has been observed in both developed and developing countries. In the winter season of 1999–2000 we detected the appearance of G9 rotavirus in Palermo, Italy, accounting for 19% of all rotaviruses circulating in our geographical area. Some of these Italian G9 isolates have been submitted to partial sequencing of their VP7 gene. All of them showed complete nucleotide identity suggesting a clonal origin. The Italian VP7 sequences were found to be very closely related to that of other G9 strains recently isolat…

Sequence analysis of the VP7 and VP4 genes identifies a novel VP7 gene allele of porcine rotaviruses, sharing a common evolutionary origin with human…

2005

AbstractDuring an epidemiological survey encompassing several porcine herds in Saragoza, Spain, the VP7 and VP4 of a rotavirus-positive sample, 34461-4, could not be predicted by using multiple sets of G- and P-type-specific primers. Sequence analysis of the VP7 gene revealed a low amino acid (aa) identity with those of well-established G serotypes, ranging between 58.33% and 88.88%, with the highest identity being to human G2 rotaviruses. Analysis of the VP4 gene revealed a P[23] VP4 specificity, as its VP8* aa sequence was 95.9% identical to that of the P14[23],G5 porcine strain A34, while analysis of the VP6 indicated a genogroup I, that is predictive of subgroup I specificity. Analysis …

S. Typhimurium virulence changes caused by exposure to different non-thermal preservation treatments using C. elegans

2017

The aims of this research study were: (i) to postulate Caenorhabditis elegans (C. elegans) as a useful organism to describe infection by Salmonella enterica serovar Typhimurium (S. Typhimurium), and (ii) to evaluate changes in virulence of S. Typhimurium when subjected repetitively to different antimicrobial treatments. Specifically, cauliflower by-product infusion, High Hydrostatic Pressure (HHP), and Pulsed Electric Fields (PEF). This study was carried out by feeding C. elegans with different microbial populations: E. coli OP50 (optimal conditions), untreated S. Typhimurium, S. Typhimurium treated once and three times with cauliflower by-product infusion, S. Typhimurium treated once and f…

Serotypes, Antibiotic Resistance, and Class 1 Integrons in Salmonella Isolates from Pediatric Cases of Enteritis in Tehran, Iran

2011

The present study was conducted to investigate serotype distribution, antimicrobial resistance patterns, carriage of class 1 integron, and clonality of Salmonella strains isolated from patients aged 0-12 years in Tehran, Iran, during 2007-2008. A total of 139 Salmonella isolates were studied. Salmonella serotypes Enteritidis, Infantis, and Typhimurium included 84.9% of isolates, Enteritidis accounting for 41.7%. The most prevalent resistances were to doxycycline (64.7%), nalidixic acid (61.2%), tetracycline (51.8%), and streptomycin (42.8%). Fifty-three (38.1%) isolates contained class 1 integron. Eight different gene cassettes were identified, aadA1 being the most frequently encountered. P…

Serotypes, antibiotic resistance, and class 1 integrons in Salmonella isolates from paediatric cases of enteritis in Tehran, Iran.

2011

Long-term survival of pathogenic and sanitation indicator bacteria in experimental biowaste composts

2005

ABSTRACT For economic, agricultural, and environmental reasons, composting is frequently used for organic waste recycling. One approach to limiting the potential risk from bacterial food-borne illnesses is to ensure that soil amendments and organic fertilizers are disinfected. However, more knowledge concerning the microbiological safety of composted substrates other than sludge and manure is necessary. Experimental in-vessel biowaste composts were used to study the survival of seeded Listeria monocytogenes , Salmonella enterica subsp. enterica serotype Enteritidis, and Escherichia coli . Four organic waste mixtures, containing various proportions of paper and cardboard, fruits and vegetabl…

AF/R2 adhesin and cytopathic effect as virulence traits of diarrhea-inducing Escherichia coli O103 in European rabbit

1995

Escherichia coli strains belonging to 0103:K-:H2 serovar and rhamnose negative biovars are responsible for frequent life-threatening diarrheas in weaned rabbits from national breeding units in western Europe (Blanco et al., 1994; Camguilhem and A. Milon, 1989). According to their mechanisms of pathogenesis, these strains may be considered as enteropathogenic E. coli (EPEC)-like. They adhere to intestinal brush border and to HeLa cells by mean of an adhesin called AF/R2 (Adhesive Factor/Rabbit 2) (Milon et al., 1990). They do not produce known toxins (i.e. ST, LT, SLT, CNF, CLDT) (Blanco et al., 1994; Mariani-Kurkdjian et al., 1993) and bear sequences homologous to EPEC eaeA (Leroy et al., 1…

2020

Coxsackievirus B (CVB) enteroviruses are common human pathogens known to cause severe diseases including myocarditis, chronic dilated cardiomyopathy, and aseptic meningitis. CVBs are also hypothesized to be a causal factor in type 1 diabetes. Vaccines against CVBs are not currently available, and here we describe the generation and preclinical testing of a novel hexavalent vaccine targeting the six known CVB serotypes. We show that the vaccine has an excellent safety profile in murine models and nonhuman primates and that it induces strong neutralizing antibody responses to the six serotypes in both species without an adjuvant. We also demonstrate that the vaccine provides immunity against …