A Novel Morphological Parameter Predicting Fibrotic Evolution in Myeloproliferative Neoplasms: New Evidence and Molecular Insights

Philadelphia-negative chronic myeloproliferative neoplasms (MPNs) represent a group of hematological disorders that are traditionally considered as indistinct slow progressing conditions; still, a subset of cases shows a rapid evolution towards myelofibrotic bone marrow failure. Specific abnormalities in the megakaryocyte lineage seem to play a central role in this evolution, especially in the bone marrow fibrosis but also in the induction of myeloproliferation. In this review, we analyze the current knowledge of prognostic factors of MPNs related to their evolution to myelofibrotic bone marrow failure. Moreover, we focused the role of the megakaryocytic lineage in the various stages of MPNs, with updated examples of MPNs in vitro and in vivo models and new therapeutic implications.     

Early Postoperative Immunothrombosis of Bioprosthetic Mitral Valve and Left Atrium: A Case Report

A 72-year-old female patient with mixed rheumatic mitral valve disease and persistent atrial fibrillation underwent mitral valve replacement and suffered from a combined thrombosis of the bioprosthetic valve and the left atrium as soon as 2 days post operation. The patient immediately underwent repeated valve replacement and left atrial thrombectomy. Yet, four days later the patient died due to the recurrent prosthetic valve and left atrial thrombosis which both resulted in an extremely low cardiac output. In this patient’s case, the thrombosis was notable for the resistance to anticoagulant therapy as well as for aggressive neutrophil infiltration and release of neutrophil extracellular traps (NETs) within the clot, as demonstrated by immunostaining. The reasons behind these phenomena remained unclear, as no signs of sepsis or contamination of the BHV were documented, although the patient was diagnosed with inherited thrombophilia that could impede the fibrinolysis. The described case highlights the hazard of immunothrombosis upon valve replacement and elucidates its mechanisms in this surgical setting.     

Mortarless structures based on topological interlocking

We review the principle of topological interlocking and analyze the properties of the mortarless structures whose design is based on this principle. We concentrate on structures built of osteomorphic blocks – the blocks possessing specially engineered contact surfaces allowing assembling various 2D and 3D structures. These structures are easy to build and can be made demountable. They are flexible, resistant to macroscopic fractures and tolerant to missing blocks. The blocks are kept in place without keys or connectors that are the weakest elements of the conventional interlocking structures. The overall structural integrity of these structures depends on the force imposed by peripheral constraint. The peripheral constraint can be provided in various ways: by an external frame or features of site topography, internal pre-stressed cables/tendons, or self-weight and is a necessary auxiliary element of the structure. The constraining force also determines the degree of delamination developing between the blocks due to bending and thus controls the overall flexibility of the structure thus becoming a new design parameter.     

Gold with a martensitic transformation: Which opportunities?

In this paper we will consider an overview of the precious alloys that could be of interest due to the inherent properties of the thermoelastic martensitic transformation that they exhibit. For sure one of the main representatives of these materials can be considered the AuAlCu system (and the related well known Spangold^TM). Actually in the literature, since the late '70s, other systems have been indicated of interest but they knew a very limited success. We refer here to some pioneering work from G.B. Brook In more recent time the increasing experience in the science and technology of conventional shape memory alloys like NiTi (which in the meantime successfully reached the application field) brought a new interest for a clear understanding of the potential of these gold alloys. Here we report on results obtained in the three areas: spangold-like alloys, AuCuZn alloys, and a ternary modification of NiTi, i.e. NiTiAu. The samples used for the investigation have been prepared starting from pure metals and thoroughly investigated by means on differential scanning calorimetry, X-ray diffraction at different temperatures and optical microscopy. When possible the samples were submitted to simple recovery test to verify the amount of shape memory and/or pseudoelastic properties.     

Characterization of synthetic hydrocalumite-type [Ca2Al(OH)6]NO3·mH2O: Effect of the calcination temperature

A lamellar hydrocalumite-type [Ca₂Al(OH)₆]NO₃·mH₂O, (HC), was synthesized and characterized by X-ray diffraction analysis (XRD), surface area, pore size measurements, CO₂-Thermal Programmed Desorption, and later tested as catalysts in the double bond isomerization of 1-butene. The layered structure of HC collapses above 523 K yielding an amorphous material at 573 K which upon calcination at 873–973 K transforms into a mixture of CaO and mayenite Ca₁₂Al₁₄O₃₃. The calcination temperature has a marked effect in the formation of basic sites. Thus for example, HC calcined at 1073 K shows 90% of strong basic sites (CO₂ desorption at 1023 K) while they are absent in HC calcined at 573–673 K. HC calcined at 973 K shows high catalytic activity (74% conversion) in the isomerization of 1-butene without any appreciable deactivation after 4 h on stream.