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The Coulomb Dissociation (CD) cross sections of the stable isotopes 92,94,100Mo and of the unstable isotope 93Mo were measured at the LAND/R3B setup at GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. Experimental data on these isotopes may help to explain the problem of the underproduction of 92,94Mo and 96,98Ru in the models of p-process nucleosynthesis. The CD cross sections obtained for the stable Mo isotopes are in good agreement with experiments performed with real photons, thus validating the method of Coulomb Dissociation. The result for the reaction 93Mo(γ,n) is especially important since the corresponding cross section has not been measured before. A preliminary integral Coulomb Dissociation cross section of the 94Mo(γ,n) reaction is presented. Further analysis will complete the experimental database for the (γ,n) production chain of the p-isotopes of molybdenum.
Microangiopathy with subsequent organ damage represents a major complication in several diseases. The mechanisms leading to microvascular occlusion include von Willebrand factor (VWF), notably the formation of ultra-large von Willebrand factor fibers (ULVWFs) and platelet aggregation. To date, the contribution of erythrocytes to vascular occlusion is incompletely clarified. We investigated the platelet-independent interaction between stressed erythrocytes and ULVWFs and its consequences for microcirculation and organ function under dynamic conditions. In response to shear stress, erythrocytes interacted strongly with VWF to initiate the formation of ULVWF/erythrocyte aggregates via the binding of Annexin V to the VWF A1 domain. VWF-erythrocyte adhesion was attenuated by heparin and the VWF-specific protease ADAMTS13. In an in vivo model of renal ischemia/reperfusion injury, erythrocytes adhered to capillaries of wild-type but not VWF-deficient mice and later resulted in less renal damage. In vivo imaging in mice confirmed the adhesion of stressed erythrocytes to the vessel wall. Moreover, enhanced eryptosis rates and increased VWF binding were detected in blood samples from patients with chronic renal failure. Our study demonstrates that stressed erythrocytes have a pronounced binding affinity to ULVWFs. The discovered mechanisms suggest that erythrocytes are essential for the pathogenesis of microangiopathies and renal damage by actively binding to ULVWFs.
In ischemic vascular diseases, leukocyte recruitment and polarization are crucial for revascularization and tissue repair. We investigated the role of vasodilator-stimulated phosphoprotein (VASP) in vascular repair. After hindlimb ischemia induction, blood flow recovery, angiogenesis, arteriogenesis, and leukocyte infiltration into ischemic muscles in VASP−/− mice were accelerated. VASP deficiency also elevated the polarization of the macrophages through increased signal transducer and activator of transcription (STAT) signaling, which augmented the release of chemokines, cytokines, and growth factors to promote leukocyte recruitment and vascular repair. Importantly, VASP deletion in bone marrow–derived cells was sufficient to mimic the increased blood flow recovery of global VASP−/− mice. In chemotaxis experiments, VASP−/− neutrophils/monocytes were significantly more responsive to M1-related chemokines than wild-type controls. Mechanistically, VASP formed complexes with the chemokine receptor CCR2 and β-arrestin-2, and CCR2 receptor internalization was significantly reduced in VASP−/− leukocytes. Our data indicate that VASP is a major regulator of leukocyte recruitment and polarization in postischemic revascularization and support a novel role of VASP in chemokine receptor trafficking.
Androgen receptor deregulation drives bromodomain-mediated chromatin alterations in prostate cancer
(2017)
Global changes in chromatin accessibility may drive cancer progression by reprogramming transcription factor (TF) binding. In addition, histone acetylation readers such as bromodomain-containing protein 4 (BRD4) have been shown to associate with these TFs and contribute to aggressive cancers including prostate cancer (PC). Here, we show that chromatin accessibility defines castration-resistant prostate cancer (CRPC). We show that the deregulation of androgen receptor (AR) expression is a driver of chromatin relaxation and that AR/androgen-regulated bromodomain-containing proteins (BRDs) mediate this effect. We also report that BRDs are overexpressed in CRPCs and that ATAD2 and BRD2 have prognostic value. Finally, we developed gene stratification signature (BROMO-10) for bromodomain response and PC prognostication, to inform current and future trials with drugs targeting these processes. Our findings provide a compelling rational for combination therapy targeting bromodomains in selected patients in which BRD-mediated TF binding is enhanced or modified as cancer progresses.
Objectives: Evaluation of surgical and non-surgical air-polishing in vitro efficacy for implant surface decontamination.
Material and methods: One hundred eighty implants were distributed to three differently angulated bone defect models (30°, 60°, 90°). Biofilm was imitated using indelible red color. Sixty implants were used for each defect, 20 of which were air-polished with three different types of glycine air powder abrasion (GAPA1–3) combinations. Within 20 equally air-polished implants, a surgical and non-surgical (with/without mucosa mask) procedure were simulated. All implants were photographed to determine the uncleaned surface. Changes in surface morphology were assessed using scanning electron micrographs (SEM).
Results: Cleaning efficacy did not show any significant differences between GAPA1–3 for surgical and non-surgical application. Within a cleaning method significant (p < 0.001) differences for GAPA2 between 30° (11.77 ± 2.73%) and 90° (7.25 ± 1.42%) in the non-surgical and 30° (8.26 ± 1.02%) and 60° (5.02 ± 0.84%) in the surgical simulation occurred. The surgical use of air-polishing (6.68 ± 1.66%) was significantly superior (p < 0.001) to the non-surgical (10.13 ± 2.75%). SEM micrographs showed no surface damages after use of GAPA.
Conclusions: Air-polishing is an efficient, surface protective method for surgical and non-surgical implant surface decontamination in this in vitro model. No method resulted in a complete cleaning of the implant surface.
Clinical relevance: Air-polishing appears to be promising for implant surface decontamination regardless of the device.
Mongolian spots (MS) are congenital dermal conditions resulting from neural crest-derived melanocytes migration to the skin during embryogenesis. MS incidences are highly variable in different populations. Morphologically, MS present as hyperpigmented maculae of varying size and form, ranging from round spots of 1 cm in diameter to extensive discolorations covering predominantly the lower back and buttocks. Due to their coloring, which is also dependent on the skin type, MS may mimic hematoma thus posing a challenge on the physician conducting examinations of children in cases of suspected child abuse. In the present study, MS incidences and distribution, as well as skin types, were documented in a collective of 253 children examined on the basis of suspected child abuse. From these data, a classification scheme was derived to document MS and to help identify cases with a need for recurrent examination for unambiguous interpretation of initial findings alongside the main decisive factors for re-examination such as general circumstances of the initial examination (e. g., experience of the examiner, lighting conditions) and given dermatological conditions of the patient (e. g., diaper rash).
Subvisible cirrus clouds (SVCs) may contribute to dehydration close to the tropical tropopause. The higher and colder SVCs and the larger their ice crystals, the more likely they represent the last efficient point of contact of the gas phase with the ice phase and, hence, the last dehydrating step, before the air enters the stratosphere. The first simultaneous in situ and remote sensing measurements of SVCs were taken during the APE-THESEO campaign in the western Indian ocean in February/March 1999. The observed clouds, termed Ultrathin Tropical Tropopause Clouds (UTTCs), belong to the geometrically and optically thinnest large-scale clouds in the Earth´s atmosphere. Individual UTTCs may exist for many hours as an only 200--300 m thick cloud layer just a few hundred meters below the tropical cold point tropopause, covering up to 105 km2. With temperatures as low as 181 K these clouds are prime representatives for defining the water mixing ratio of air entering the lower stratosphere.
Nicotinamid-3-desazapurindinucleotid * wurde aus den Teilstücken Nicotinamidmononucleotid und 3-Desazapurinribosid-5'-phosphat durch Kondensation mit Dicyclohexylcarbodiimid in wäßrigem Pyridin hergestellt1. Das Coenzymmodell war im enzymatischen Test mit verschiedenen Dehydrogenasen ebenso wirksam wie Nicotinamid-adenin-dinucleotid. Für die Funktion der Wasserstoffübertragung scheint der Stickstoff N 1 im Purinring von Bedeutung zu sein. Auffällig ist, daß die pK-Werte nichtfunktioneller Mononucleotidteile bei Coenzymmodellen, die Nicotinamid-adenin-dinucleotid im enzymatischen Test ersetzen können, über dem Wert 4 liegen. Das optische Verhalten des Coenzymmodells Nicotinamid-3-desazapurin-dinucleotid ähnelt dagegen nichtpurinhaltigen Coenzymmodellen, die sich bisher alle durch eine geringere Coenzymwirksamkeit auszeichneten. Eine schwächere intramolekulare Wechselwirkung zwischen den Heterocyclen zeichnete sich durch die Verschiebung des Dihydronicotinamid-Absorptionsmaximums in dem kurzwelligen Teil des Spektrums aus. Aus den geringeren intramolekularen Wechselwirkungen lassen sich jedoch keine Rückschlüsse auf die enzymatische Wirksamkeit ziehen. Alle nichtpurinhaltigen hydrierten Coenzymmodelle zeigen keine Änderung der Fluoreszenz nach Enzymzugabe.
Die Synthese des Coenzymmodells Flavin-benzimidazol-dinucleotid * gelang durch Kondensation von Benzimidazolribotid-imidazolid 1 oder Benzimidazolribotid-guanidiniumamidat 2 mit Flavinmononucleotid. Das Coenzymmodell war enzymatisch nicht aktiv und bildete keinen Enzym-Coenzym-Komplex. Im Absorptionsspektrum konnte eine Extinktionszunahme nach der Spaltung der Pyrophosphatbrücke nur im Bereich von 260 mμ beobachtet werden. Das Molekül liegt daher vermutlich in einer gefalteten Form vor. Ein Komplex zwischen Flavin- und Benzimidazolteil konnte nicht nachgewiesen werden. Eine Fluoreszenzunterdrückung, die im FAD durch die Komplexbildung zwischen Flavin- und Adeninteil bedingt wird, wurde im FBD-Coenzymmodell nicht beobachtet.
Mechanisms by which subvisible cirrus clouds (SVCs) might contribute to dehydration close to the tropical tropopause are not well understood. Recently Ultrathin Tropical Tropopause Clouds (UTTCs) with optical depths around 10-4 have been detected in the western Indian ocean. These clouds cover thousands of square kilometers as 200-300 m thick distinct and homogeneous layer just below the tropical tropopause. In their condensed phase UTTCs contain only 1-5% of the total water, and essentially no nitric acid. A new cloud stabilization mechanism is required to explain this small fraction of the condensed water content in the clouds and their small vertical thickness. This work suggests a mechanism, which forces the particles into a thin layer, based on upwelling of the air of some mm/s to balance the ice particles, supersaturation with respect to ice above and subsaturation below the UTTC. In situ measurements suggest that these requirements are fulfilled. The basic physical properties of this mechanism are explored by means of a single particle model. Comprehensive 1-D cloud simulations demonstrate this stabilization mechanism to be robust against rapid temperature fluctuations of +/- 0.5 K. However, rapid warming (Delta T > 2 K) leads to evaporation of the UTTC, while rapid cooling (Delta T < -2 K) leads to destabilization of the particles with the potential for significant dehydration below the cloud