Interactions between endocarditis-derived Streptococcus gallolyticus subsp. gallolyticus isolates and human endothelial cells

<p>Abstract</p> <p>Background</p> <p><it>Streptococcus gallolyticus </it>subsp. <it>gallolyticus </it>is an important causative agent of infective endocarditis (IE) but the knowledge on virulence factors is limited and the pathogenesis of the infection is poorly understood. In the present study, we established an experimental <it>in vitro </it>IE cell culture model using EA.hy926 and HUVEC cells to investigate the adhesion and invasion characteristics of 23 <it>Streptococcus gallolyticus </it>subsp. <it>gallolyticus </it>strains from different origins (human IE-derived isolates, other human clinical isolates, animal isolates). Adhesion to eight components of the extracellular matrix (ECM) and the ability to form biofilms <it>in vitro </it>was examined in order to reveal features of <it>S. gallolyticus </it>subsp. <it>gallolyticus </it>endothelial infection. In addition, the strains were analyzed for the presence of the three virulence factors <it>gtf</it>, <it>pilB</it>, and <it>fimB </it>by PCR.</p> <p>Results</p> <p>The adherence to and invasion characteristics of the examined <it>S. gallolyticus </it>subsp. <it>gallolyticus </it>strains to the endothelial cell line EA.hy926 differ significantly among themselves. In contrast, the usage of three different <it>in vitro </it>models (EA.hy926 cells, primary endothelial cells (HUVECs), mechanical stretched cells) revealed no differences regarding the adherence to and invasion characteristics of different strains. Adherence to the ECM proteins collagen I, II and IV revealed the highest values, followed by fibrinogen, tenascin and laminin. Moreover, a strong correlation was observed in binding to these proteins by the analyzed strains. All strains show the capability to adhere to polystyrole surfaces and form biofilms. We further confirmed the presence of the genes of two known virulence factors (<it>fimB</it>: all strains, <it>gtf</it>: 19 of 23 strains) and demonstrated the presence of the gene of one new putative virulence factor (<it>pilB</it>: 9 of 23 strains) by PCR.</p> <p>Conclusion</p> <p>Our study provides the first description of <it>S. gallolyticus </it>subsp. <it>gallolyticus </it>adhesion and invasion of human endothelial cells, revealing important initial information of strain variability, behaviour and characteristics of this as yet barely analyzed pathogen.</p

Myelodysplastic syndromes: Aspects of current medical care and economic considerations in Germany

Myelodysplastic syndromes (MDS) are a heterogeneous group of diseases mainly affecting older people. The use of an increasing number of therapeutic options depends on a systematic risk stratification of the patients. A high percentage of MDS patients need blood transfusions as supportive care, which influence quality of life and cause a great part of the costs generated by MDS therapy. In this article which is based on a workshop about the burden of MDS held in October 2006 in Munich, MDS is discussed with regard to different aspects: current therapies, transfusion medicine, geriatrics, quality of life, and health economic aspects

Regulated mitochondrial DNA replication during oocyte maturation is essential for successful porcine embryonic development.

Cellular ATP is mainly generated through mitochondrial oxidative phosphorylation, which is dependent on mitochondrial DNA (mtDNA). We have previously demonstrated the importance of oocyte mtDNA for porcine and human fertilization. However, the role of nuclear-encoded mitochondrial replication factors during oocyte and embryo development is not yet understood. We have analyzed two key factors, mitochondrial transcription factor A (TFAM) and polymerase gamma (POLG), to determine their role in oocyte and early embryo development. Competent and incompetent oocytes, as determined by brilliant cresyl blue (BCB) dye, were assessed intermittently during the maturation process for TFAM and POLG mRNA using real-time RT-PCR, for TFAM and POLG protein using immunocytochemistry, and for mtDNA copy number using real-time PCR. Analysis was also carried out following treatment of maturing oocytes with the mtDNA replication inhibitor, 2',3'-dideoxycytidine (ddC). Following in vitro fertilization, preimplantation embryos were also analyzed. Despite increased levels of TFAM and POLG mRNA and protein at the four-cell stage, no increase in mtDNA copy number was observed in early preimplantation development. To compensate for this, mtDNA appeared to be replicated during oocyte maturation. However, significant differences in nuclear-encoded regulatory protein expression were observed between BCB(+) and BCB(-) oocytes and between untreated oocytes and those treated with ddC. These changes resulted in delayed mtDNA replication, which correlated to reduced fertilization and embryonic development. We therefore conclude that adherence to the regulation of the timing of mtDNA replication during oocyte maturation is essential for successful embryonic development

Risks for human and animal health related to the presence of phorbol esters in Jatropha kernel meal

The Panel wishes to thank the members of the Working Group on Phorbol Esters: Bruce Cottrill, Stefano Dall'Acqua, Johanna Fink-Gremmels, Harinder P.S. Makkar and Manfred Metzler for the preparatory work on this scientific opinion, and EFSA staff: Marco Binaglia, Karen Mackay and Rositsa Serafimova for the support provided to this scientific opinion.Peer reviewedPublisher PD

Presence of microplastics and nanoplastics in food, with particular focus on seafood

The Panel wishes to thank the members of the Working Group on the presence of microplastics and nanoplastics in food, with particular focus on seafood: Francesco Cubadda, Christer Hogstrand, Peter Hollman, Hendrik Van Loveren, Anne-Katrine Lundebye and Annette Petersen for the preparatory work on this statement, the hearing expert: Stephanie Wright and EFSA staff member: Karen Mackay for the support provided to this statement.Peer reviewedPublisher PD

Acute health risks related to the presence of cyanogenic glycosides in raw apricot kernels and products derived from raw apricot kernels

Peer reviewedPublisher PD

Malachite green in food

The Panel wishes to thank the members of the Standing Working Group on non-allowed pharmacologically active substances in food and feed and their reference points for action (2015–2018): Metka Filipič, Peter Fürst, Laurentius (Ron) Hoogenboom, Anne-Katrine Lundebye, Carlo Stefano Nebbia, Michael O'Keeffe and Rolaf Van Leeuwen for the preparatory work on this scientific output, the hearing expert: Eva Persson, and EFSA staff members: Katleen Baert and Sofia Ioannidou for the support provided to this scientific opinion. The CONTAM Panel acknowledges all European competent institutions and other stakeholders that provided occurrence data on malachite green and leucomalachite green in food, and supported the data collection for the Comprehensive European Food Consumption Database.Peer reviewedPublisher PD

Statin therapy inhibits remyelination in the central nervous system

Remyelination of lesions in the central nervous system contributes to neural repair following clinical relapses in multiple sclerosis. Remyelination is initiated by recruitment and differentiation of oligodendrocyte progenitor cells (OPCs) into myelinating oligodendrocytes. Simvastatin, a blood-brain barrier-permeable statin in multiple sclerosis clinical trials, has been shown to impact the in vitro processes that have been implicated in remyelination. Animals were fed a cuprizone-supplemented diet for 6 weeks to induce localized demyelination in the corpus callosum; subsequent return to normal diet for 3 weeks stimulated remyelination. Simvastatin was injected intraperitoneally during the period of coincident demyelination and OPC maturation (weeks 4 to 6), throughout the entire period of OPC responses (weeks 4 to 9), or during the remyelination-only phase (weeks 7 to 9). Simvastatin treatment (weeks 4 to 6) caused a decrease in myelin load and both Olig2(strong) and Nkx2.2(strong) OPC numbers. Simvastatin treatment (weeks 4 to 9 and 7 to 9) caused a decrease in myelin load, which was correlated with a reduction in Nkx2.2(strong) OPCs and an increase in Olig2(strong) cells, suggesting that OPCs were maintained in an immature state (Olig2(strong)/Nkx2.2(weak)). NogoA+ oligodendrocyte numbers were decreased during all simvastatin treatment regimens. Our findings suggest that simvastatin inhibits central nervous system remyelination by blocking progenitor differentiation, indicating the need to monitor effects of systemic immunotherapies that can access the central nervous system on brain tissue-repair processes

Risks for human health related to the presence of pyrrolizidine alkaloids in honey, tea, herbal infusions and food supplements

The Panel wishes to acknowledge all European competent institutions, Member State bodies and other organisations that provided data for this scientific output. Adopted: 21 June 2017Peer reviewedPublisher PD

Scientific opinion on the evaluation of substances as acceptable previous cargoes for edible fats and oils

The Panel wishes to thank the members of the Working Group on acceptable previous cargoes for edible fats and oils – Previous cargoes 2016: Bettina Grasl-Kraupp, Konrad Grob, André Penninks and Christiane Vleminckx and EFSA staff members: Marco Binaglia and Ruth Roldán Torres. The Panel acknowledges the European Chemicals Agency that provided data on ammonium sulphate.Peer reviewedPublisher PD