Infective endocarditis (IE) incidence remains high with considerable fatality rates; guidelines for prophylaxis against IE are currently under review in some settings which highlights the importance of maintaining up-to-date epidemiological estimates about the most common microbial causes. The objective of this systematic review, following PRISMA guidelines, was to identify the most common microbial causes of IE in recent years. Medline was searched from January 1, 2003 to March 31, 2013 for all articles containing the term "infective endocarditis". All relevant studies reporting diagnostic results were included. Special patient subpopulations were assessed separately. A total of 105 studies were included, from 36 countries, with available data on a total of 33,214 cases. Staphylococcus aureus was found to be the most common microorganism, being the most frequent in 54.3 % of studies (N = 57) (and in 55.4 % of studies using Duke's criteria for diagnosis [N = 51]). Viridans group streptococci (VGS), coagulase-negative staphylococci (CoNS), Enterococcus spp and Streptococcus bovis were among the most common causes. S. aureus was the most common pathogen in almost all population subgroups; however, this was not the case in patients with implantable devices, prosthetic valves, or immunocompromised non-HIV, as well as in the sub-group from Asia, emphasizing that a global one-size-fits-all approach to the management of suspected IE is not appropriate. This review provides an evidence-based map of the most common causative agents of IE, highlighting S. aureus as the leading cause in the 21st century. The changing epidemiology of IE in some patient sub-groups in the last decade and the very high number of microbiologically undiagnosed cases (26.6 %) suggest the need to revisit IE prophylaxis and diagnostic strategies.

Abstract. Breast cancer (BrCa) is the most common malignancy among women worldwide, and one of the leading causes of cancer-related deaths in females. Despite the development of novel therapeutic modalities, triple-negative breast cancer (TNBC) remains an incurable disease. Androgen receptor (AR) is widely expressed inBreast cancer (BrCa) is the most common solid tumor among women with an annual incidence of 123 new cases/100,000 females according to the United States Cancer Statistics and 252.710 estimated new cases in the U.S. in 2017. Despite significant progress made in therapeutics during the last 2 decades, BrCa still has a poor prognosis with 5-year survival rates of metastatic disease reaching to 26% only. BrCa is the second leading cause of death among female cancers with 40,610 estimated deaths in the U.S. expected in 2017 (1).Breast cancer comprises a heterogeneous group of diseases with variable course and outcome. Currently, BrCa is subclassified into distinct molecular subtypes named: normal breast like, luminal A/B, HER-2 related, basal-like and claudinlow (2, 3). Estrogen receptor (ER), progesterone receptor (PR) and HER2 have long been established as useful prognostic and predictive biomarkers. Hormonal therapy in ER and PR positive tumors (4), as well as the use of monoclonal antibodies in HER2 over-expressing tumors (5) have shown promising results, however overall survival of metastatic disease remains relatively low (1). To date, androgen receptor (AR) has been suggested to play a key role in breast cancer biology in certain disease subgroups (6, 7).AR is expressed in all stages of breast cancer (in-situ, primary and metastatic disease) and its contribution to the progression of disease may differ depending on the stage (8). Overall, AR expression among patients with breast cancer has been estimated at approximately 77% and varies significantly among molecular subtypes of BrCa (9). Human observational studies have associated AR with better outcome in ER + tumors, but this positive effect may be lost in ER-tumors (10, 11). Of interest, AR expression correlates with better clinicopathological features in the most aggressive form of BrCa, triple-negative breast cancer (TNBC) (12). AR seems to have distinct roles in disease development and progression depending on the tumor's hormonal environment and specifically upon relative levels of androgens and estrogens.The historically used androgens together with antiandrogens, Selective AR Modulators (SARMs) and Androgen Receptor antagonists constitute valuable options for the treatment of specific disease subpopulations. In the past decade, a wealth body of studies have focused on AR targeting along with hampering major signaling pathways 6533 This Αrticle is freely accessible online.