Association between biomass formation and the prognosis of infective endocarditis due to Staphylococcus aureus.

Introduction: The aim of this study was to evaluate the association between biomass formation and the clinical characteristics and prognosis of Staphylococcus aureus infective endocarditis (IE).

Methods: We prospectively studied 209 S. aureus strains causing IE.

Molecular Epidemiology of Bacteremia: Association of Molecular Factors With the Source of Infection.

bacteremia (SAB) is associated with high morbidity and mortality, which varies depending on the source of infection. Nevertheless, the global molecular epidemiology of SAB and its possible association with specific virulence factors remains unclear. Using DNA microarrays, a total of 833 strains (785 SAB and 48 colonizing strains) collected in Spain over a period of 15 years (2002-2017) were characterized to determine clonal complex (CC), type and repertoire of resistance and virulence genes in order to provide an epidemiological overview of CCs causing bloodstream infection, and to analyze possible associations between virulence genes and the most common sources of bacteremia.

Sub-inhibitory concentrations of oxacillin modify the expression of agr locus in Staphylococcus aureus clinical strains belonging to different clonal complexes.

Background: The ability of Staphylococcus aureus to invade tissues and cause an infectious disease is the result of a multi-factorial process supported by the huge number of virulence factors inherent to this microorganism tightly regulated by the accessory gene regulator (agr). During antimicrobial therapy bacteria may be exposed to sub-inhibitory concentrations (subMICs) of antibiotics that may trigger transcriptional changes that may have an impact on the pathogenesis of infection. The objective of this study was to investigate the effect of oxacillin sub-MICs on agr system expression as the key component in the regulation of virulence in methicillin-susceptible (MSSA) and -resistant S.

Characterization of mobile genetic elements carrying VIM-1 and KPC-2 carbapenemases in Citrobacter freundii isolates in Madrid.

Carbapenemase producing Citrobacter freundii (CPCF) infections are still uncommon in European countries. Here we report a molecular study conducted in a tertiary care facility in southern Madrid, Spain, from 2009 to 2014 to investigate the epidemiology of CPCF. The blablablablablabla and bla genes were screened by PCR.

Pathogenic Characteristics of Endovascular Infection Isolates from Different Clonal Complexes.

is a major cause of bacteremia and, even with appropriate clinical management, causes high morbidity, and mortality due to its involvement in endovascular complications and metastatic infections. Through different pathogenic and models we investigated the behavior of most relevant clonal complexes (CCs) causing endovascular complications. We analyzed 14 strains representing CC5, CC8, CC15, CC30, and CC45 that caused endovascular complications, including methicillin susceptible and resistant isolates and strains with different functionality of the global regulator.

Influence of molecular characteristics in the prognosis of methicillin-resistant Staphylococcus aureus prosthetic joint infections: beyond the species and the antibiogram.

We have explored the relationship of phenotypic (antibiogram, β-haemolysis, agr functionality, biofilm formation) and genotypic characteristics on the prognosis of 18 cases of methicillin-resistant S. aureus prosthetic joint infection (2005-2015). All isolates belonged to CC5, and had agr type II.

Chlorhexidine and mupirocin susceptibilities in methicillin-resistant Staphylococcus aureus isolates from bacteraemia and nasal colonisation.

Chlorhexidine and mupirocin have been increasingly used in healthcare facilities to eradicate methicillin-resistant Staphylococcus aureus (MRSA) carriage. The aim of this study was to determine the prevalence and mechanisms of chlorhexidine and mupirocin resistance in MRSA from invasive infections and colonisation. MRSA isolates obtained from blood and nasal samples between 2012 and 2014 were analysed.

Haplotypic diversity of porcine LEP and LEPR genes involved in growth and fatness regulation.

The analysis of structural genetic variability in candidate genes can make it possible to analyse the selection footprint and deepen the understanding of the genetic basis of complex traits. The leptin (LEP) and its receptor (LEPR) porcine genes are involved in food intake and energy homeostasis, and polymorphisms associated to growth and fatness traits have been detected in both genes. The main objective of this study was to explore the genetic variability of the most polymorphic regions of both genes in a variety of pig populations and wild boars from diverse European and Asian origins.

Differences in muscle transcriptome among pigs phenotypically extreme for fatty acid composition.

Background: Besides having an impact on human health, the porcine muscle fatty acid profile determines meat quality and taste. The RNA-Seq technologies allowed us to explore the pig muscle transcriptome with an unprecedented detail. The aim of this study was to identify differentially-expressed genes between two groups of 6 sows belonging to an Iberian × Landrace backcross with extreme phenotypes according to FA profile.

Identification of genes regulating growth and fatness traits in pig through hypothalamic transcriptome analysis.

Previous studies on Iberian × Landrace (IBMAP) pig intercrosses have enabled the identification of several quantitative trait locus (QTL) regions related to growth and fatness traits; however, the genetic variation underlying those QTLs are still unknown. These traits are not only relevant because of their impact on economically important production traits, but also because pig constitutes a widely studied animal model for human obesity and obesity-related diseases. The hypothalamus is the main gland regulating growth, food intake, and fat accumulation.

Transcriptional Characterization of Porcine Leptin and Leptin Receptor Genes.

The leptin (LEP) and its receptor (LEPR) regulate food intake and energy balance through hypothalamic signaling. However, the LEP-LEPR axis seems to be more complex and its expression regulation has not been well described. In pigs, LEP and LEPR genes have been widely studied due to their relevance.

Polymorphism in the ELOVL6 gene is associated with a major QTL effect on fatty acid composition in pigs.

Background: The ELOVL fatty acid elongase 6 (ELOVL6), the only elongase related to de novo lipogenesis, catalyzes the rate-limiting step in the elongation cycle by controlling the fatty acid balance in mammals. It is located on pig chromosome 8 (SSC8) in a region where a QTL affecting palmitic, and palmitoleic acid composition was previously detected, using an Iberian x Landrace intercross. The main goal of this work was to fine-map the QTL and to evaluate the ELOVL6 gene as a positional candidate gene affecting the percentages of palmitic and palmitoleic fatty acids in pigs.

Porcine tissue-specific regulatory networks derived from meta-analysis of the transcriptome.

The processes that drive tissue identity and differentiation remain unclear for most tissue types. So are the gene networks and transcription factors (TF) responsible for the differential structure and function of each particular tissue, and this is particularly true for non model species with incomplete genomic resources. To better understand the regulation of genes responsible for tissue identity in pigs, we have inferred regulatory networks from a meta-analysis of 20 gene expression studies spanning 480 Porcine Affymetrix chips for 134 experimental conditions on 27 distinct tissues.

Genome-wide linkage analysis of QTL for growth and body composition employing the PorcineSNP60 BeadChip.

Background: The traditional strategy to map QTL is to use linkage analysis employing a limited number of markers. These analyses report wide QTL confidence intervals, making very difficult to identify the gene and polymorphisms underlying the QTL effects. The arrival of genome-wide panels of SNPs makes available thousands of markers increasing the information content and therefore the likelihood of detecting and fine mapping QTL regions.