Systemic sclerosis-associated myositis features minimal inflammation and characteristic capillary pathology

Systemic sclerosis represents a chronic connective tissue disease featuring fibrosis, vasculopathy and autoimmunity, affecting skin, multiple internal organs, and skeletal muscles. The vasculopathy is considered obliterative, but its pathogenesis is still poorly understood. This may partially be due to limitations of conventional transmission electron microscopy previously being conducted only in single patients. The aim of our study was therefore to precisely characterize immune inflammatory features and capillary morphology of systemic sclerosis patients suffering from muscle weakness. In this study, we identified 18 individuals who underwent muscle biopsy because of muscle weakness and myalgia in a cohort of 367 systemic sclerosis patients. We performed detailed conventional and immunohistochemical analysis and large-scale electron microscopy by digitizing entire sections for in-depth ultrastructural analysis. Muscle biopsies of 12 of these 18 patients (67%) presented minimal features of myositis but clear capillary alteration, which we termed minimal myositis with capillary pathology (MMCP). Our study provides novel findings in systemic sclerosis-associated myositis. First, we identified a characteristic and specific morphological pattern termed MMCP in 67% of the cases, while the other 33% feature alterations characteristic of other overlap syndromes. This is also reflected by a relatively homogeneous clinical picture among MMCP patients. They have milder disease with little muscle weakness and a low prevalence of interstitial lung disease (20%) and diffuse skin involvement (10%) and no cases of either pulmonary arterial hypertension or renal crisis. Second, large-scale electron microscopy, introducing a new level of precision in ultrastructural analysis, revealed a characteristic capillary morphology with basement membrane thickening and reduplications, endothelial activation and pericyte proliferation. We provide open-access pan-and-zoom analysis to our datasets, enabling critical discussion and data mining. We clearly highlight characteristic capillary pathology in skeletal muscles of systemic sclerosis patients

Phase Transformations in the Brazing Joint during Transient Liquid Phase Bonding of a γ-TiAl Alloy Studied with In Situ High-Energy X-Ray Diffraction

TiAl alloys are increasingly used as a lightweight material, for example in aero engines,which also leads to the requirement for suitable repair techniques. Transient liquid phase bonding isa promising method for the closure of cracks (in non-critical or non-highly loaded areas). Thebrazing solder Ti-24Ni was investigated for brazing the alloy Ti-45Al-5Nb-0.2B-0.2C (in at. %).After brazing, the joint exhibits different microstructures and phase compositions.The transient liquid phase bonding process was investigated in the middle of the joint region insitu to acquire time resolved information of the phases, their development, and thus the brazingprocess.These investigations were performed using high-energy X-ray diffraction at the “High-EnergyMaterials Science” beamline HEMS, located at the synchrotron radiation facility PETRA III atDESY in Hamburg, Germany. For this, we used an induction furnace, which is briefly describedhere.During the analysis of the diffraction data with Rietveld refinement, the amount of liquid wasrefined with Gaussian peaks and thus could be quantified. Furthermore, while brazing four differentphases occurred in the middle of the joint region over time. Additionally, the degree of ordering ofthe βo phase was determined with two ideal stoichiometric phases (completely ordered anddisordered). Altogether, the phase composition changed clearly over the first six hours of thebrazing process

P05 imaging beamline at PETRA III: first results

The imaging beamline (IBL/P05) operated by Helmholtz Zentrum Geesthacht (HZG) at the DESY PETRA III storage ring consists of two experimental stations: A micro tomography and a nano tomography end station. Here an overview of the experimental setups and the data acquisition will be given. In addition some first results out of the wide range of applications using the micro tomography station at P05 will be shown. Furthermore, we present first results of the nano tomography end station. These were obtained with an x–ray microscopy setup, which currently operates at energies of 17.4 and 30 keV using polymer compound refractive lenses (CRLs) and rolled prism lenses. Taken together these results clearly show the high potential of the newly built imaging beamline IBL

P05 imaging beamline at PETRA III: first results

The imaging beamline (IBL/P05) operated by Helmholtz Zentrum Geesthacht (HZG) at the DESY PETRA III storage ring consists of two experimental stations: A micro tomography and a nano tomography end station. Here an overview of the experimental setups and the data acquisition will be given. In addition some first results out of the wide range of applications using the micro tomography station at P05 will be shown. Furthermore, we present first results of the nano tomography end station. These were obtained with an x–ray microscopy setup, which currently operates at energies of 17.4 and 30 keV using polymer compound refractive lenses (CRLs) and rolled prism lenses. Taken together these results clearly show the high potential of the newly built imaging beamline IBL

Biodegradable magnesium-based implants in bone studied by synchrotron radiation microtomography

Permanent implants made of titanium or its alloys are the gold standard in many orthopedic and traumatological applications due to their good biocompatibility and mechanical properties. However, a second surgical intervention is required for this kind of implants as they have to be removed in the case of children that are still growing or on patient's demand. Therefore, magnesium-based implants are considered for medical applications as they are degraded under physiological conditions. The major challenge is tailoring the degradation in a manner that is suitable for a biological environment and such that stabilization of the bone is provided for a controlled period. In order to understand failure mechanisms of magnesium-based implants in orthopedic applications and, further, to better understand the osseointegration, screw implants in bone are studied under mechanical load by means of a push-out device installed at the imaging beamline P05 of PETRA III at DESY. Conventional absorption contrast microtomography and phasecontrast techniques are applied in order to monitor the bone-to-implant interface under increasing load conditions. In this proof-of-concept study, first results from an in situ push-out experiment are presented

Micro-CT at the imaging beamline P05 at PETRA III

The Imaging Beamline (IBL) P05 is operated by the Helmholtz-Zentrum Geesthacht and located at the DESY storage ring PETRA III. IBL is dedicated to X-ray full field imaging and consists of two experimental end stations. A micro tomography end station equipped for spatial resolutions down to 1 μm and a nano tomography end station for spatial resolutions down to 100 nm. The micro tomography end station is in user operation since 2013 and offers imaging with absorption contrast, phase enhanced absorption contrast and phase contrast methods. We report here on the current status and developments of the micro tomography end station including technical descriptions and show examples of research performed at P05