Extracellular DNA in blood: an index of <i>in vivo</i> inflammatory response

Increased concentration of cell-free DNA (cfDNA) in the circulating blood of humans and animals is a sign of inflammatory conditions and a distinctive characteristic of various pathophysiological processes in the body. The aim of the present study was to investigate the possible role of tumor necrosis factor (TNFα) in changes of cfDNA contents in peripheral blood as a response to experimentally induced systemic inflammation.We used 40 female hybrid mice (C57Bl/6xDBA/2) F1 at the age of 6-8 weeks. The concentration of cfDNA and its individual fractions was determined using a PicoGreen fluorescent dye. The dynamics of inflammatory process was evaluated after 4, 8, 11 and 24 hours following LPS injection. A significant increase in the blood plasma cfDNA levels was shown under the action of E. coli lipopolysaccharide (LPS), along with simultaneous decreased levels of cfDNA, associated with cell surface. The ratio of cell surface-bound cfDNA to the total cfDNA contents was reduced in dose-dependent manner as early as 4 hours after LPS injection to the animals, thus allowing us to consider this ratio a characteristic sign of netosis of neutrophilic granulocytes during the development of acute inflammation. The described effects are significantly suppressed with co-injection of recombinant TNFα neutralizing protein along with LPS, whereas increased intake of neutrophils in the tissues is determined by some other factors which are not directly related to the production of this cytokine.Based on the obtained data, we proposed a following hypothesis: induction of netosis by inflammatory stimuli causes an increase in the concentration of cfDNA in blood plasma not only due to de novo emerging extracellular DNA by neutrophil netosis, but also by the release of distinct cfDNA fraction that was previously firmly bound to cell membranes in multiple body tissues under the action of proteases released during netosis

Blood platelets in chronic graft-versus-host disease: association with Th1/Th2 ratio

As found in clinical and laboratory studies, platelets not only play a key role in the processes of coagulation and thrombosis, but are also able to actively participate in other pathophysiological processes, including the development of immune reactions. It has been shown that changes in the immune system leading to systemic lupus erythematosus (SLE) are often accompanied by changes in the number of platelets and their activity in the peripheral blood of SLE patients, which correlate with the severity of the clinical manifestations of the disease. Earlier we have studied the standard experimental model of SLE in detail, based on the induction of chronic graft-versus-host disease (cGVHD) in the semi-allogeneic system DBA/2 → (C57Bl/6 x DBA/2)F1. However, the participation of platelets in this immunopathological process has not been studied. There are no data in the literature on the behavior of platelets in cGVHD or on their relationship with the state of Th1/Th2 balance. It can been expected that the platelet count changes according to the development of cGVHD in the used experimental model by analogy with the development of SLE in humans.In the experiments, we used female mice of the DBA/2 strain and (C57Bl/6 × DBA/2)F1 hybrids. Chronic GVHD in a semi-allogeneic system was induced by injecting DBA/2 mouse splenocytes into B6D2F1 hybrid mice: 60-70 × 106 cells intravenously twice with an interval of 6 days. The studied parameters were evaluated three months after the start of the experiment and the formation of lupus-like glomerulonephritis in animals with Th2-dependent cGVHD variant.A decrease in the number of erythrocytes and hemoglobin, a decrease in hematocrit and a parallel increase in the number of reticulocytes in the blood of mice with cGVHD are in good agreement with our earlier conclusion that these animals have autoimmune hemolytic anemia. It was found that, platelets increase significantly with the development of cGVHD unlike other blood cells. Secondary thrombocytosis is observed in the case of the Th2-dependent variant of сGVHD in this model of SLE, while in the group with the Th1-dependent variant of сGVHD, the average number of platelets in the blood does not differ from the control group

Effect of the Centrifugal Barrier of the Nuclear for Neutron Moderation

The aim of the work was to study the parameters of the elastic moderation of neutrons in the potential field of the centrifugal barrier of the moderator nuclei. It has been established that due to the action of the centrifugal potential field of the moderator nuclei, the neutron energy decreases

Nonlinear superchiral meta-surfaces: tuning chirality and disentangling non-reciprocity at the nanoscale.

Circularly polarized light is incident on a nanostructured chiral meta-surface. In the nanostructured unit cells whose chirality matches that of light, superchiral light is forming and strong optical second harmonic generation can be observed

Nanostripe length dependence of plasmon-induced material deformations

Following the impact of a single femtosecond light pulse on nickel nanostripes, material deformations—or “nanobumps”—are created. We have studied the dependence of these nanobumps on the length of nanostripes and verified the link with plasmons. More specifically, local electric currents can melt the nanostructures in the hotspots, where hydrodynamic processes give rise to nanobumps. This process is further confirmed by independently simulating local magnetic fields, since these are produced by the same local electric currents

Nonlinear Superchiral Meta-Surfaces: Tuning Chirality and Disentangling Non-Reciprocity at the Nanoscale

Circularly polarized light is incident on a nanostructured chiral meta-surface. In the nanostructured unit cells whose chirality matches that of light, superchiral light is forming and strong optical second harmonic generation can be observed.status: publishe