STED lithography in microfluidics for 3D thrombocyte aggregation testing

Three-dimensional photopolymerization techniques such as multiphoton polymerization lithography (MPL) and stimulated emission depletion (STED) lithography are powerful tools for fabricating structures in the sub-µm range. Combining these techniques with microfluidics enables us to broaden the range of their applications. In this study, we show a microfluidic device enhanced with MPL structures carrying STED-lithographically written nanoanchors that promote binding of the von Willebrand factor (vWF). The density of vWF is adjusted by varying the number of the nanoanchors on the 3D structures. This allows us to study the impact of the density of vWF on the activation of thrombocytes. The activation of the thrombocytes seems to decrease with the density of vWF on the 3D scaffolds inside the microfluidic channels.

Pulmonary stromal expansion and intra-alveolar coagulation are primary causes of Covid-19 death

SummaryMost Covid-19 victims are old and die from unrelated causes. Here we present twelve complete autopsies, including two rapid autopsies of young patients where the cause of death was Covid-19 ARDS. The main virus induced pathology was in the lung parenchyma and not in the airways. Most coagulation events occurred in the intra-alveolar and not in the intra-vascular space and the few thrombi were mainly composed of aggregated thrombocytes. The dominant inflammatory response was the massive accumulation of CD163+ macrophages and the disappearance of T killer, NK and B-cells. The virus was replicating in the pneumocytes and macrophages but not in bronchial epithelium, endothel, pericytes or stromal cells. The lung consolidations were produced by a massive regenerative response, stromal and epithelial proliferation and neovascularization. We suggest that thrombocyte aggregation inhibition, angiogenesis inhibition and general proliferation inhibition may have a roll in the treatment of advanced Covid-19 ARDS.

Thrombocyte Aggregative Activity of Irshire Breed Calves of Milk Nutrition

Evaluation of blood indices and especially hemostasis elements of productive cattle has great practical meaning for biology. They are closely connected with their somatic characteristics and functioning processes of the whole organism. Clarification of their values allows to work out age-specific norms of given indices and to define clearly the beginning of hemostasiopathy coming. High productivity of Irshire cattle and great meaning of thrombocyte activity of its cubs enduced to make evaluation of blood platelets aggregation. The aim of the work: to define peculiarities of thrombocyte activity of Irshire breed healthy calves during milk nutrition phase. There was fulfilled the investigation of 65 milk nutrition calves of Irshire breed with the usage of hematological research methods. The most active thrombocyte aggregation was noted for adenosine diphosfate being maximum to the end of investigation. Collagenous and rhystomitzine aggregation had less intensity and similar direction what indirectly pointed at not high collagen availability and not large Willybrand’s factor concentration in it. Deaggregative thrombocyte capabilities in response to all the used inductors in case of Irshire calves of milk nutrition had tendency to growth. Not high thrombocyte activity provides cattle of this breed during growth and development optimal conditions for blood supply of growing and ripening organs.