Background: The population at risk, the clinical and microbiological features of infective endocarditis (IE) have changed. Aim of our study was to evaluate the contemporary epidemiological trends, over a 17-year period in a definite region of Tuscany, Italy, to analyze the clinical outcomes and associated prognostic factors.Methods: From 1 January 1998 to 31 December 2014, all patients with a definite diagnosis of IE were prospectively entered in a data-base. The Health-Care system data-base was interrogated to capture patients who could have been missed. The final dataset derived by the merging of the two data-bases.Results: Incidence rate of IE was 4.6/100,000/y with a significant linear incidence increase. In hospitalized patients the incidence was 1.27/1,000 admissions. Over age 65 incidence rate was 11.7/100,000/y.Male/female ratio was 1.54:1. A temporal trend towards an increase in the mean population age was found (P=0.033). There was an increase in the incidence of Health-care associated IE, P=0.016. The most common microorganisms were staphylococcus aureus (25%) and coagulase-negative staphylococci (22%).In-hospital mortality was 24%. A trend towards an increase in mortality rate was found (P=0.055).Independent predictors of mortality were older age, S. aureus infection, heart failure, septic shock and persistent bacteremia. Conclusions:Our study confirms an increasing mortality trend in IE, although with a borderline significance. Elderly forms are associated with poor prognosis and higher than 1-year mortality rate even in the multivariate analysis. Ageing population, increase in healthcare-associated and staphylococcal infections, may explain the rise of IE incidence and of the mortality trend.

No abstract

Mesenchymal stem cells (MSCs) are adult multipotent cells able to differentiate toward mature mesodermal lineages. In spite of more than a decade of investigation, little is known about the molecular mechanisms regulating the undifferentiated state and the identity of distinct functional subpopulations in these cells. Transcription factors that regulate the maintenance of the pluripotent state in embryonic stem cells, including NANOG, SOX2, and OCT4, have been proposed to play a similar role also in adult stem cells, although with conflicting results. We performed a critical evaluation of expression of these 3 transcription factors and found that NANOG, but not OCT-4 and SOX-2, is expressed in cultured human adult MSCs. Actually, NANOG was not expressed in freshly isolated MSCs, but was detected only after in vitro culture. NANOG was detected only in proliferating cells, but not in MSCs induced to differentiate. The percentage of cells expressing NANOG was maintained throughout early passages of MSCs, but then started to decrease in late passages in MSCs from adipose tissue and heart but not from bone marrow. However, the number of NANOG-expressing cells did not associate with the proliferative and differentiative capabilities of MSC populations, neither its expression appeared to identify cells having stem or progenitor cell properties. Accordingly, we propose that activation of NANOG expression in MSCs is associated with, although cannot directly regulate, the transition from in vivo quiescence to adaptation to in vitro growth conditions.

This is the first population study on PCT, a rare disease with an incidence rate of 1.38 new cases per 100,000 residents per year.