Bacterial pathogens causing systemic disease commonly evolve from organisms associated with localized infections but differ from their close relatives in their ability to overcome mucosal barriers by mechanisms that remain incompletely understood. Here we investigated whether acquisition of a regulatory gene, tviA, contributed to the ability of Salmonella enterica serotype Typhi to disseminate ...

Agent-based modeling provides a means for addressing the way human and natural systems interact to change landscapes over time. Until recently, evaluation of simulation models has focused on map comparison techniques that evaluate the degree to which predictions match real-world observations. However, methods that change the focus of evaluation from patterns to processes have begun to surface; ...

The synthesis and transportation proteins of the Vi capsular polysaccharide of Salmonella enterica serovar Typhi (serovar Typhi) are encoded by the viaB operon, which resides on a 134-kb pathogenicity island known as SPI-7. In recent years, Vi-negative strains of serovar Typhi have been reported in regions where typhoid fever is endemic. However, because Vi negativity can arise during in vitro ...

Salmonella entericaserovar Typhi remains a major public health problem in many developing countries .The severity and pathogenesis of the disease depending on virulence factors. Previously, different virulence factors have been detected phenotypically and serologically for clinical and epidemiological investigation of salmonella. Beyond the phenotypic characterization, a reliable molecular meth...

Delivery of microbial products into the mammalian cell cytosol by bacterial secretion systems is a strong stimulus for triggering pro-inflammatory host responses. Here we show that Salmonella enterica serovar Typhi (S. Typhi), the causative agent of typhoid fever, tightly regulates expression of the invasion-associated type III secretion system (T3SS-1) and thus fails to activate these innate i...

To discern virulent from innocuous microbes, the innate immune system senses events associated with bacterial access to immunoprivileged sites such as the host cell cytosol. One such pathway is triggered by the cytosolic delivery of flagellin, the major subunit of the flagellum, by bacterial secretion systems. This leads to inflammasome activation and subsequent proinflammatory cell death (pyro...

AIMS The study set out to assess the relative contributions of donor heart rate, respiration and recipient atrial contraction on the mean of pulsed wave transmitral Doppler flow indices in orthotopic heart transplant recipients. This would provide information on the theoretical usefulness of pacemaker synchronization of recipient atrial contraction, as well as on the validity of certain strateg...

The purpose of this study was to evaluate the influence of diabetes mellitus on left ventricular function. Using Doppler echocardiography we examined a group of 49 young (20-32 years old) persons with type 1 diabetes mellitus and a group of healthy age-matched men and evaluated the parameters of diastolic filling of the left ventricle (LV). We found significant differences in peak velocity of e...