Staphylococcus aureus contains an autoinducing quorum-sensing system encoded within the agr operon that coordinates expression of virulence genes required for invasive infection. Allelic variation within agr has generated four agr specific groups, agr I-IV, each of which secretes a distinct autoinducing peptide pheromone (AIP1-4) that drives agr signaling. Because agr signaling mediates a pheno...

We previously reported that the cvfB gene (SA1223) of Staphylococcus aureus is responsible for the virulence of this pathogenic bacterium. We show here that the cvfB gene regulates exoprotein gene expression. In a cvfB gene deletion mutant, hemolysin, DNase, and protease production were decreased, whereas protein A expression was increased. The amount of RNAIII, the transcript from the P3 promo...

We apply the “almost good reduction” (AGR) criterion, which has been introduced in our previous works, to several classes of discrete integrable equations. We verify our conjecture that AGR plays the same role for maps of the plane define over simple finite fields as the notion of the singularity confinement does. We first prove that q-discrete analogues of the Painlevé III and IV equations hav...

Introduction. Nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA) represents a risk for the spread of bacteria. This study characterized the S. aureus isolated from medical students, who were in their clinical rotation at a hospital in the city of Cali. Materials and Methods. 216 students participated in the study and 63 isolates of S. aureus were evaluated for susceptibility a...

This study evaluated the predictive value of the preoperative albumin/globulin ratio (AGR) in laryngeal squamous cell carcinoma (LSCC) retrospectively, which has not been reported before. The current study enrolled 241 newly diagnosed LSCC patients in the Second Affiliated Hospital of Nanchang University between January 2005 and December 2010. The optimal AGR cut-off value for overall survival ...

Most verification tools and methodologies such as model checking, equivalence checking, hardware verification, software verification, and hardware-software coverification often flatten out the behavior of a target system before verification. Inherent modularities, either explicit or implicit, functional or structural, are not exploited by these tools and algorithms. In this work, we show how as...

Inactivating mutations in the Staphylococcus aureus virulence regulator agr are associated with worse outcomes in bacteremic patients. However, whether agr dysfunction is primarily a cause or a consequence of early bacteremia is unknown. Analysis of 158 paired S. aureus clones from blood and nasal carriage sites in individual patients revealed that recovery of an agr-defective mutant from blood...

The effects of the accessory gene regulator (agr) and glucose on staphylococcal enterotoxin type C (SEC) gene (sec+) expression were examined. For the agr studies, a Tn551 insertionally inactivated agr was transferred into two different sec+ Staphylococcus aureus strains. Western blot (immunoblot) analysis showed that each of the sec+ Agr- derivatives produced less extracellular SEC than their ...

OBJECTIVE Characterization of Staphylococcus aureus clinical isolates derived from lower respiratory tract infections (LRTIs), and correlation between the functionality of the accessory gene regulator (Agr) and genotypic and phenotypic characteristics, clinical variables and clinical outcome. METHODS S aureus isolates derived from LRTIs and control groups (nasal carriage and bacteraemia) were...

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the leading causes of nosocomial infections and a major public health concern worldwide. During the last decade, MRSA of CC398 have emerged as important colonizers of livestock. These strains also represent an increasing cause of human infections. A recent study reporting a new dominant spa type among MRSA from Finish fattening pigs (...