Management of aneurysmal subarachnoid hemorrhage patients with antiplatelet use before the initial hemorrhage: an international survey

INTRODUCTION The case fatality in aneurysmal subarachnoid hemorrhage (aSAH) is 50% due to the initial hemorrhage or subsequent complications like aneurysmal rebleed or delayed cerebral ischemia (DCI). One factor that might influence the initial brain damage or subsequent complications is the use of antiplatelet medication before the initial hemorrhage. The goal of this survey was to assess the different management options of patients with aSAH with antiplatelet use before the initial hemorrhage. MATERIAL AND METHODS An anonymous survey of 11 multiple-choice questions about management of aSAH patients with antiplatelet use before the initial hemorrhage was distributed to the international panel of attendees of the European Association of Neurosurgical Societies (EANS) annual meeting in Venice, Italy at 1-5 October 2017. RESULTS A total of 258 (54%) completed surveys were returned. In about 80%, the departments of neurosurgery and neurology were responsible for acute management of aSAH patients, whereas in 15% the intensive care unit. Department guidelines were present in 32%. In 65%, the responders always stop the antiplatelet agent at admission and in 4.3% are thrombocytes always transfused. When a guideline is present, the neurospecialists consider thrombocyte transfusion more often (83% vs. 65% p=0.02). CONCLUSION Our survey among mainly European neurosurgeons show that there is a significant variability in the management of aSAH patients who have been using antiplatelets before the initial hemorrhage. These findings emphasize the importance of the development of evidence-based guidelines for management of patients with aSAH and antiplatelet use before the initial hemorrhage

An intracellular pH gradient in the anammox bacterium Kuenenia stuttgartiensis as evaluated by 31P NMR

The cytoplasm of anaerobic ammonium oxidizing (anammox) bacteria consists of three compartments separated by membranes. It has been suggested that a proton motive force may be generated over the membrane of the innermost compartment, the “anammoxosome”. 31P nuclear magnetic resonance (NMR) spectroscopy was employed to investigate intracellular pH differences in the anammox bacterium Kuenenia stuttgartiensis. With in vivo NMR, spectra were recorded of active, highly concentrated suspensions of K. stuttgartiensis in a wide-bore NMR tube. At different external pH values, two stable and distinct phosphate peaks were apparent in the recorded spectra. These peaks were equivalent with pH values of 7.3 and 6.3 and suggested the presence of a proton motive force over an intracytoplasmic membrane in K. stuttgartiensis. This study provides for the second time—after discovery of acidocalcisome-like compartments in Agrobacterium tumefaciens—evidence for an intracytoplasmic pH gradient in a chemotrophic prokaryotic cell

The polygonal cell shape and surface protein layer of anaerobic methane-oxidizing Methylomirabilis ianthanidiphila bacteria

This is the final version. Available from Frontiers Media via the DOI in this record. The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found below: ProteomeXchange, PXD029319; EMDB, EMD-13672 and EMD-13670; and EMPIAR, EMPIAR-10822 and EMPIAR-10829Methylomirabilis bacteria perform anaerobic methane oxidation coupled to nitrite reduction via an intra-aerobic pathway, producing carbon dioxide and dinitrogen gas. These diderm bacteria possess an unusual polygonal cell shape with sharp ridges that run along the cell body. Previously, a putative surface protein layer (S-layer) was observed as the outermost cell layer of these bacteria. We hypothesized that this S-layer is the determining factor for their polygonal cell shape. Therefore, we enriched the S-layer from M. lanthanidiphila cells and through LC-MS/MS identified a 31 kDa candidate S-layer protein, mela_00855, which had no homology to any other known protein. Antibodies were generated against a synthesized peptide derived from the mela_00855 protein sequence and used in immunogold localization to verify its identity and location. Both on thin sections of M. lanthanidiphila cells and in negative-stained enriched S-layer patches, the immunogold localization identified mela_00855 as the S-layer protein. Using electron cryo-tomography and sub-tomogram averaging of S-layer patches, we observed that the S-layer has a hexagonal symmetry. Cryo-tomography of whole cells showed that the S-layer and the outer membrane, but not the peptidoglycan layer and the cytoplasmic membrane, exhibited the polygonal shape. Moreover, the S-layer consisted of multiple rigid sheets that partially overlapped, most likely giving rise to the unique polygonal cell shape. These characteristics make the S-layer of M. lanthanidiphila a distinctive and intriguing case to study.European CommissionEuropean Research CouncilOCW/NWO Gravitation grantEuropean Research CouncilNetherlands Organisation for Scientific Research (NWO

Rolled-Up Nanotech: Illumination-Controlled Hydrofluoric Acid Etching of AlAs Sacrificial Layers

<p>Abstract</p> <p>The effect of illumination on the hydrofluoric acid etching of AlAs sacrificial layers with systematically varied thicknesses in order to release and roll up InGaAs/GaAs bilayers was studied. For thicknesses of AlAs below 10 nm, there were two etching regimes for the area under illumination: one at low illumination intensities, in which the etching and releasing proceeds as expected and one at higher intensities in which the etching and any releasing are completely suppressed. The &#8220;etch suppression&#8221; area is well defined by the illumination spot, a feature that can be used to create heterogeneously etched regions with a high degree of control, shown here on patterned samples. Together with the studied self-limitation effect, the technique offers a way to determine the position of rolled-up micro- and nanotubes independently from the predefined lithographic pattern.</p

Varieties of living things: Life at the intersection of lineage and metabolism

publication-status: Publishedtypes: Articl

Trending topics and open questions in anaerobic ammonium oxidation.

Item does not contain fulltextAnaerobic ammonium-oxidizing (anammox) bacteria are major players in the biological nitrogen cycle and can be applied in wastewater treatment for the removal of nitrogen compounds. Anammox bacteria anaerobically convert the substrates ammonium and nitrite into dinitrogen gas in a specialized intracellular compartment called the anammoxosome. The anammox cell biology, physiology and biochemistry is of exceptional interest but also difficult to study because of the lack of a pure culture, standard cultivation techniques and genetic tools. Here we review the most important recent developments regarding the cell structure - anammoxosome and cell envelope - and anammox energy metabolism - nitrite reductase, hydrazine synthase and energy conversion - including the trending topics electro-anammox, extracellular polymeric substances and ladderane lipids

The Anammoxosome Organelle Is Crucial for the Energy Metabolism of Anaerobic Ammonium Oxidizing Bacteria

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