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1.
Int J Cardiol Heart Vasc ; 33: 100766, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33869726

RESUMO

AIMS: To identify an imbalance of cardiac remodeling mediators and monocytes subpopulation in blood, distribution of myocardium macrophages in patients with ischemic cardiomyopathy (ICMP). METHODS: The study engaged 30 patients with ICMP, 26 patients with coronary heart disease (CHD) without ICMP, 15 healthy donors. Concentrations of TGFß, MMP-9, MCP-1, galectin-3 were measured in plasma of blood from the coronary sinus and peripheral blood in CHD patients, as well as in peripheral blood in healthy donors, by enzyme immunoassay method. The ration of classical, intermediate, non-classical, transitional monocytes in peripheral blood of patients and healthy donors was assessed by flow cytometry (expression CD14, CD16); the content of CD68+ macrophages in myocardium - by immunohistochemistry method. RESULTS: In both samples of blood, the content of galectin-3 in patients with ICMP was higher than in CHD patients without ICMP and the level of TGFß was comparable between the groups. At ICMP, the concentration of MMP-9 in sinus blood was higher than that in CHD patients without ICMP in whom an excess of MCP-1 in the general blood flow was determined. The density of distribution of CD68+ cells in the myocardium in patients with ICMP was higher in the perianeurysmal zone than in the right atrium appendage. ICMP was characterized by a deficiency of non-classical monocytes, and CHD without ICMP - by an excess of intermediate cells in peripheral blood. CONCLUSION: Myocardium remodeling at ICMP is mediated by not so much TGFß but intracardiac galectin-3, which determines the subpopulation composition of blood monocytes.

2.
Sci Rep ; 10(1): 18898, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33144640

RESUMO

The paper presents new knowledge on primary defect formation in tungsten (W) and iron (Fe) irradiated by fission and high-energy neutrons at near-room temperature. Using a well-established method of positron-annihilation lifetime-spectroscopy (PALS), it was found that irradiation of W in the fission reactor and by high-energy neutrons from the p(35 MeV)-Be generator leads to the formation of small radiation-induced vacancy clusters with comparable mean size. In the case of Fe, smaller mean size of primary radiation-induced vacancy clusters was measured after irradiation with fission neutrons compared to irradiation with high-energy neutrons from the p(35 MeV)-Be generator. It was found that one of the reasons of the formation of the larger size of the defects with lower density in Fe is lower flux in the case of irradiation with high-energy neutrons from the p(35 MeV)-Be source. The second reason is enhanced defect agglomeration and recombination within the energetic displacement cascade at high energy primary knock-on-atoms (PKAs). This is consistent with the concept of the athermal recombination corrected (arc-dpa) model, although the measured dpa cross-section of both fission neutrons and wide-spectrum high-energy neutrons in W is between the conventional Norgett-Robinson-Torrens (NRT-dpa) and arc-dpa predictions. This means that the physics of the primary radiation effects in materials is still not fully known and requires further study through a combination of modeling and experimental efforts. The present data serve as a basis for the development of an improved concept of the displacement process.

3.
Appl Radiat Isot ; 106: 145-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26249744

RESUMO

The reliability of Fricke gel dosimeters in form of layers for measurements aimed at the characterization of epithermal neutron beams has been studied. By means of dosimeters of different isotopic composition (standard, containing (10)B or prepared with heavy water) placed against the collimator exit, the spatial distribution of gamma and fast neutron doses and of thermal neutron fluence are attained. In order to investigate the accuracy of the results obtained with in-air measurements, suitable MC simulations have been developed and experimental measurements have been performed utilizing Fricke gel dosimeters, thermoluminescence detectors and activation foils. The studies were related to the epithermal beam designed for BNCT irradiations at the research reactor LVR-15 (Rez). The results of calculation and measurements have revealed good consistency of gamma dose and fast neutron 2D distributions obtained with gel dosimeters in form of layers. In contrast, noticeable modification of thermal neutron fluence is caused by the neutron moderation produced by the dosimeter material. Fricke gel dosimeters in thin cylinders, with diameter not greater than 3mm, have proved to give good results for thermal neutron profiling. For greater accuracy of all results, a better knowledge of the dependence of gel dosimeter sensitivity on radiation LET is needed.


Assuntos
Terapia por Captura de Nêutron/instrumentação , Dosagem Radioterapêutica , Modelos Teóricos , Método de Monte Carlo
5.
Artigo em Inglês | MEDLINE | ID: mdl-1815317

RESUMO

The authors describe a flat stainless steel container with two necks of the volume 160-180 ml, manufactured according to their own design as well as their first experience with controlled-rate freezing of leukocytes and/or peripheral blood stem cells (PBSC) in this container. The containers meet the requirements of clinical application, i.e. they are made of non-toxic stainless steel, the inner and outer surfaces are polished electrochemically, sterilization by autoclaving is possible, several containers can be frozen simultaneously in a freezing chamber of a programmable freezer and storage of containers in both vapour and liquid phase of nitrogen is possible. Analysis of the cell volume distribution in suspensions of leukocytes and PBSC collected by hemapheresis showed high recovery of cells after thawing. The advantages and disadvantages of metal containers in comparison with disposable plastic bags are discussed in detail.


Assuntos
Medula Óssea , Criopreservação/instrumentação , Criopreservação/métodos , Humanos
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