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1.
Vopr Pitan ; 90(1): 6-14, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33740323

RESUMO

Vitamin D with its steroid structure is currently considered as a hormone. New target cells of this hormone have been identified, including those in the organs of the reproductive system. The aim - to analyze modern sources of domestic and foreign scientific literature covering the role of vitamin D in the reproductive health of women of different ages. Results. The Russian Federation is endemic in terms of vitamin D deficiency. According to statistics, a lack of this vitamin is observed in 70-90% of the population of the USA and European countries, which brings this problem to the international level. It has been established that vitamin D affects not only bone-mineral homeostasis, but also many organs and tissues, including the reproductive system, namely the ovaries, uterus, placental tissue, pituitary gland and male reproductive organs. Studies have proven the positive effect of this hormone on the course of polycystic ovary syndrome, endometriosis, diabetes mellitus (including gestational). In addition, it has been shown that vitamin D is an important micronutrient during pregravid preparation, and the normalization of its level can improve the quality and increase the life expectancy of women after 50-60 years. Conclusion. Vitamin D plays an important role in many physiological processes, including the effects on the organs of the reproductive system. The significant influence of this vitamin can be traced from the beginning of intrauterine development to the end of life, which makes its further study an important area of modern medicine, including within the framework of obstetrics and gynecology.


Assuntos
Síndrome do Ovário Policístico , Deficiência de Vitamina D , Feminino , Humanos , Masculino , Oxilipinas , Placenta , Gravidez , Vitamina D
2.
Nanotechnology ; 31(21): 215301, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31978916

RESUMO

In this paper we demonstrate a nanofabrication technique based on local ion irradiation of silicon dioxide with a focused helium ion beam. The wet etching of silicon dioxide irradiated with a focused helium ion beam is described in a two-dimensional case both numerically and experimentally. We suggest a model for the etching process based on the distribution of ion induced defects in the irradiated material. The profile of the surface of the etched silicon dioxide is simulated and compared with the results from scanning electron microscopy. Fabrication of a suspended nanostring with a diameter of less than 20 nm by means of etching ion-irradiated material is demonstrated.

3.
J Opt Soc Am A Opt Image Sci Vis ; 36(9): 1505-1511, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503844

RESUMO

Periodical spatial modulation of the excitonic resonance in a quantum well could lead to the formation of a new highly directional and resonant coherent optical response-resonant diffraction. Such excitonic diffraction gratings were demonstrated in epitaxially grown quantum wells patterned by low-dose ion beam irradiation before or after the growth. In this paper we present a theoretical model of the resonant diffraction formation based on the step-by-step approximation of the Maxwell equation solution. The resulting theory allows us to reliably describe experimental data as well as to predict a way to increase the diffraction efficiency.

4.
Gynecol Endocrinol ; 33(sup1): 36-40, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29264986

RESUMO

To evaluate the prognostic value of a comprehensive endometrial study after early reproductive losses (RL). A group of 306 women with early RL (missed abortion (n = 120), spontaneous miscarriage (n = 120), and ineffective in vitro fertilization attempts (n =66) were prospectively examined up to 6 months after the discharge of the uterus at the hospital bases of the Department of Obstetrics and Gynecology with the Сourse of perinatology at the PFUR Medical Faculty. Hysteroscopic macrotypes differentiation - hyperplastic (n = 89), hypoplastic (n = 94) and mixed (n = 87) - was carried out on the basis of features grouping characterizing the thickness, color and structure of the mucosa, the intensity of a vascular pattern in the presence of a chronic endometritis (CE). Evaluation of sonographic accuracy after hysteroscopic CE macrotypes differentiation showed the presence of false-negative conclusions: about unchanged mucosa (6.9%); endometrium polyps (3.5%); intrauterine synechiae (4.2%). Immunohistochemical staining with CD138 isolation showed higher diagnostic accuracy in CE detecting in comparison with the morphological method: in a hyperplastic macrotype (90.5% and 84.1%, respectively), hypo- (93.7% and 89.8%) and mixed (81.6% and 79.4%). Great diagnostic value is shown in identifying histopathic CE features in the context of hysteroscopic macrotypes differentiation in groups of women with RL.


Assuntos
Endometrite/diagnóstico , Endométrio/patologia , Adulto , Endometrite/diagnóstico por imagem , Endometrite/patologia , Endométrio/diagnóstico por imagem , Feminino , Humanos , Pólipos/diagnóstico por imagem , Pólipos/patologia , Prognóstico , Estudos Prospectivos , Ultrassonografia , Doenças Uterinas/diagnóstico por imagem , Doenças Uterinas/patologia , Adulto Jovem
5.
Tsitologiia ; 59(1): 62-8, 2017.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-30188104

RESUMO

Cultivation of cells under artificial conditions is one of the necessary procedures when working with stem cells. At this stage, the cells lose control by the macroorganism, becoming independent systems. Therefore, during the passaging of the cells, the probability of undesirable modifications is increased. At present, there is not enough data on the first indications about modification of the cultured cells and when they can appear. In the work, the rabbit medullary mesenchymal stromal cells (MSCs) were studied during 5 passages after producing primary culture. The area and the spreading coefficient of a cell were used to evaluate the cell state. The measurements were made 1 h and 1 day after cell reseeding by analyzing digital images of intact living cells. During this time interval, the absolute values of the cell area increased with the passage number, whereas the increment of the cell growth area did not depend on the passage number. It is possible to distinguish three groups of cells. Smaller cells (the 1st group) prevail in cell population of the 1st passage. Next, their proportion is decreased and the proportion of larger cells is increased. Passaging of the cells does not influence their spreading coefficient.


Assuntos
Forma Celular , Células-Tronco Mesenquimais/citologia , Animais , Adesão Celular , Técnicas de Cultura de Células , Células Cultivadas , Células-Tronco Mesenquimais/metabolismo , Coelhos , Fatores de Tempo
6.
Tsitologiia ; 59(3): 185-93, 2017.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-30183166

RESUMO

We studied proliferative features of cells in monolayer line of rat hepatoma Zajdela (the original, parent line) and in the sublines 3H and 9C cloned from different types of the colonies of the parental line. These sublines also differed by cytomorphometric parameters, by the types of colonies formed at recloning of these cells in vitro, and by tumorogenicity at transplantation to a rat. Using a time-lapse video of native living cells, we analyzed the cell cycle duration (CCD) and its relationship to a cell shape. Direct measurement of the CCD (a time period from mitosis to mitosis) was performed in individual cells of non-synchronized cultures. Average value of CCD in the parent Zajdela line appeared to be 14.6 ± 0.2 hours, that was higher (at P < 0.05) than in 3H and 9C sublines (13.9 ± 0.2 and 13.5 ± 0.3 hours, respectively). The analysis of CCD distribution histogram showed that all three lines contained a common population of cells with CCD close to 14 hours. Besides, the parent cell line had about 1/3 of cells with a higher CCD (16.7 ± 0.2 hours) while the subline 9C had, on the contrary, 1/3 of cells with a lower CCD (12.6 ± 0.1 hours). In addition, the parameters of cell area, coefficient of cell spreading and coefficient of cell polarization showed the highest correlation to CCD in cells of subline 3H, which are primarily fibroblast-shaped cells (P < 0.01) : the larger the cell area, the longer the CCD; the more flattened or polarized the cell is, the shorter its CCD. In the parental cell line and the subline 9C, both consisting of preferably epithelium-shaped cells, the correlation between CCD and cell shape was less pronounced and showed the opposite direction, that may be explained by a difference in the origin of the cell lines. When considering the differences of CCD in the pairs of daughter cells, we introduce the concept of «the coefficient of symmetry of a cell division¼. The lower its value, the greater the similarity of CCD in a pair of daughter cells. Possible connection of the cell parameters studied in vitro to the tumorigenicity of these cells is discussed.


Assuntos
Carcinoma Hepatocelular/metabolismo , Ciclo Celular , Neoplasias Hepáticas/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Neoplasias Hepáticas/patologia , Ratos
7.
Opt Lett ; 41(1): 104-6, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26696169

RESUMO

We propose a method of spatial modulation of inhomogeneous broadening of a quantum-well excitonic resonance based on local generation of defects produced by a focused ion beam. The method is applied to fabrication of excitonic diffraction grating in a single quantum-well InGaAs/GaAs structure by irradiating the sample with a beam of 35-keV He+ ions of exposure doses <1012 cm-2. The spectrum of resonant diffraction on such a structure is narrower than that of reflectivity and decreases much faster with increasing temperature. A proposed model of formation of the diffractive response based on the single scattering approximation well describes the results of the spectral and temperature measurements.

8.
Tsitologiia ; 58(7): 548-54, 2016.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-30198669

RESUMO

It is generally accepted that nuclear erythrocytes of some vertebrates are shaped like ellipses. Nevertheless, the formal proof for this has not been presented. Here, the experimental data and theoretical calculations are presented to prove that the shape of nuclear erythrocytes, as a mathematical expectation, is really the ellipse. In addition, allowable limits of deviation of the erythrocytes shape from the ellipse were shown. On the basis of the presented data we have introduced a new parameter (named «ellipsoid coefficient¼) to evaluate how the real cell shape fits to the correct ellipse. The coefficient is the ratio of the real erythrocyte area (A) to the calculated area (S) obtained by a direct measurement of the erythrocyte major (M) and minor (m) axes. We assume that this parameter can be used in taxonomy of the vertebrate animals having nuclear erythrocytes.


Assuntos
Núcleo Celular , Forma Celular , Eritrócitos/citologia , Animais , Peixes , Ranidae
9.
Tsitologiia ; 58(1): 35-43, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27220250

RESUMO

Development of regenerative medicine based on the use of stem cells is substantially dependent on the prediction of the changes that the cells undergo after culturing them in vitro. Therefore, the accumulation of knowledge in the field, which can be denoted as biology of cells in culture, is of special importance. Features of functioning cells in vitro is better to study in the permanent cells lines as their morphological and functional characteristics in numerous passages can be regarded as the result of adaptation of cells to grow outside the body. The aim of the present study was to test whether there is a relationship between the density of the cell culture prior to the formation of a monolayer of cells and morphometric parameters of the cells. The NCTC fibroblast-like cells (clone 929 were examined one day after reseeding. By this time, the culture density was such that there was virtually no direct contact between the cells. The cell area, spreading and polarization coefficients were used to characterize the cells. It has been shown that, in the same culture flask, the cells in the areas with a higher density of cells are smaller than in areas of lower density. At the same time, polarization of cells increases by increasing the cell density. Such cell reaction may be the result of the remote transfer of information between the cells. Analysis of the data obtained allows us to assume that the change in shape of the cells is related to early steps of monolayer formation.


Assuntos
Comunicação Celular/fisiologia , Fibroblastos/citologia , Animais , Contagem de Células , Linhagem Celular , Polaridade Celular , Proliferação de Células , Tamanho Celular , Camundongos , Microscopia
10.
Voen Med Zh ; 337(5): 4-10, 2016 05.
Artigo em Russo | MEDLINE | ID: mdl-30592573

RESUMO

The authors underwent an analysis of doctrine changes of battle-field surgery. The terminology is specified, the ways of improvement of effectiveness and quality of medical care for the wounded, taking into account the new doctrine, are formulated. In accordance with Federal law No 323-FZ of 2011.11.21 the term < is suggested for description of medical care at medical forward treatment unit instead of equalfied aid>.


Assuntos
Cirurgia Geral , Medicina Militar/normas , Procedimentos Cirúrgicos Operatórios , Lesões Relacionadas à Guerra/cirurgia , Cirurgia Geral/métodos , Cirurgia Geral/organização & administração , Cirurgia Geral/normas , História do Século XXI , Humanos , Medicina Militar/história , Medicina Militar/métodos , Medicina Militar/organização & administração , Procedimentos Cirúrgicos Operatórios/métodos , Procedimentos Cirúrgicos Operatórios/normas , Lesões Relacionadas à Guerra/história
11.
Tsitologiia ; 57(5): 370-8, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26281214

RESUMO

The period (1 h after reseeding) of behaviour of mouse NCTC clone 929 cells to the conditions of artificial cultivation was studied. The time-lapse imaging followed the processing of the cells with ImageJ program was applied. To characterize the parametres cell status we used the cell area (projection of the cell on substrate) and Rp/Ra ratio introduced earlier as a spreading coefficient (Kuz'minykh, Petrov, 2004). After attaching a substratum, cells have a form of sphere (the phase "sphere") as the daughter cells after a mitosis. We revealed however that after this phase the reseeded cells do not start usual spreading and migration along substratum. They pass a phase of equally spreading in all directions and shaping their area as a circle (phase "circle"). This phase is absent of the daughter cells spreading after mitosis. We assume that the phase "circle" is a result of adaptation of the cells to reseedings at artificial cultivation. It is necessary for formation of a substrate composed of own extracellular matrix components (ECM) of the cells. Own ECM facilitates transition of the cells to their usual spreading and migration along substratum.


Assuntos
Movimento Celular/fisiologia , Matriz Extracelular/metabolismo , Fibroblastos/fisiologia , Animais , Adesão Celular , Linhagem Celular , Proliferação de Células , Forma Celular , Células Clonais , Meios de Cultura/química , Matriz Extracelular/química , Fibroblastos/ultraestrutura , Camundongos , Mitose , Imagem com Lapso de Tempo
12.
Tsitologiia ; 57(8): 578-83, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26591569

RESUMO

The present paper is an attempt to estimate the influence of cell surface morphology changes to functional activity under the effect of antioxidant, N-acetylcysteine (NAC), and alpha-lipoic asid (ALA). Two experimental parameters were used to characterize transformed fibroblasts 3T3-SV40 status. The functional one was the cell sensitivity to lysis by natural killer (NK) mouse splenocytes, and morphology index (cell form index) was a cell area. We showed that addition of NAC or ALA to the cell medium caused fast decrease of cell area and changes of cell form. On the other hand, their sensitivity to lysis NK cells gradually and significantly decreased. Then we compared NAC or ALA effect with the effects of other substances, which were non-antioxidants but caused cell responses which concurred with of antioxidants, at least partly. They were: latrunculin B, desorganizing actin filaments (as both antioxidants), OTZ reducing ROS level in the cell (as NAC), BSO (inhibitor of glutathione synthesis), increasing ROS level in the cell (as ALA), antibodies to gelatinases, MMP-2 and MMP-9 inactivating their activities (as both antioxidants). The results obtained showed a correlation between changes of morphology index and functional activity, sensitivity to lysis by NK cells. We suppose that geometry of cell surface might be a functional indicator of cell reaction to the antioxidant.


Assuntos
Antioxidantes/farmacologia , Forma Celular/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Transformada , Técnicas de Cocultura , Repressão Enzimática , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Metionina Sulfoximina/análogos & derivados , Metionina Sulfoximina/farmacologia , Camundongos , Células NIH 3T3 , Ácido Pirrolidonocarboxílico/farmacologia , Tiazolidinas/farmacologia , Ácido Tióctico/farmacologia
13.
Data Brief ; 28: 104980, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31909103

RESUMO

Interaction of ultrashort laser pulses with materials can bring the latter to highly non-equilibrium states, where the electronic temperature strongly differs from the ionic one. The properties of such excited material can be considerably different from those in a hot, but equilibrium state. The reliable modeling of laser-irradiated target requires careful analysis of its properties in both regimes. This paper reports a procedure which provides the equations of state of ruthenium using density functional theory calculations. The obtained data are fitted with analytical functions. The constructed equations of state are applicable in the one- and two-temperature regimes and in a wide range of densities, temperatures and pressures. The electron thermal conductivity and electron-phonon coupling factor are also calculated. The obtained analytical expressions can be used in two-temperature hydrodynamics modeling of Ru targets pumped by ultrashort laser pulses. The data is related to the research article "Similarity in ruthenium damage induced by photons with different energies: From visible light to hard X-rays" [1].

14.
Rev Sci Instrum ; 89(8): 083509, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30184710

RESUMO

A diagnostic system for plasma radiated power tomography on Globus-M was upgraded with a new linear array based on silicon photodiodes. The hardware of the diagnostic system based on a 256-channel tangential matrix array and a 24-channel linear array is described. The algorithm for 2D tomographic reconstruction of plasma emissivity is presented. It uses the Tikhonov regularization method and anisotropic diffusion functional as a side constraint. Simulated plasma emissivity profiles were used to test and assess the capabilities of the developed algorithm. Data analysis was carried out in ohmic and neutral beam heated discharges to demonstrate the performance of the tomography diagnostic in plasmas with different parameters. The presented results illustrate the proper functioning of the tomography system that allowed to reveal and study various plasma phenomena, including magnetohydrodynamic mode.

15.
Materials (Basel) ; 10(9)2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28872618

RESUMO

We present the results of magnetic force microscopy investigations of domain structures in multilayer [Co (0.5 nm)/Pt (1 nm)]5 thin film structures (denoted hereafter as Co/Pt) modified by additional Co capping layers and by ion irradiation. It is demonstrated that a Co capping layer essentially changes the domain structure and decreases the threshold of magnetization reversal, due to the formation of noncollinear magnetization in Co/Pt. It is shown that local irradiation with a focused He⁺ ion beam enables the formation of regions with decreased easy-axis anisotropy (magnetic bubbles) that have the inverse magnetization direction in the demagnetized state of Co/Pt. The experimental results demonstrate that the magnetic bubbles can be switched using a probe of a magnetic force microscope. The possible application of these effects for the development of magnetic logic and data storage systems is discussed.

16.
Mater Sci Eng C Mater Biol Appl ; 58: 1024-35, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26478400

RESUMO

In this work, biomedical Co-28Cr-6Mo alloy is subjected to ultrasonic impact treatment (UIT). XRD, TEM and SAED analyses show that the plastic deformation induced by the UIT process results in a complex microstructural formation in surface layer of Co-28Cr-6Mo alloy. The peculiar feature observed in the alloy structure by TEM is the formation of Lomer-Cottrell locks originated by simultaneous sliding of Shockley partial dislocations in intersecting planes. At the beginning of the UIT process (till the strain extent e ≈ 0.2), dislocation pile-ups are gathered in front of the Lomer-Cottrell locks stimulating the formation of a great number of chaotic stacking faults (SFs) packets (incompletely transformed martensite), which are predominant with regard to the occurrence of ε-martensite and micro-twins. The incompletely transformed martensite hinders the shear translation through the twin boundaries and suppresses grain subdivision in surface layer of Co-28Cr-6Mo alloy at the UIT process used. On-going deformation to e ≈ 0.4 leads to further modification of microstructure in the micron-scale γ-grains, which consists of numerous Lomer-Cottrell locks, chaotic subtraction SFs, intersected nano-twins and fine lathes of ε-martensite with average size of approx. 50-100 nm. The observed structural features (at e ≈ 0.4) allow adequately explaining noticeable increase in microhardness without any cracks/cleavages in surface layer. Enhanced corrosion resistance of Co-28Cr-6Mo alloy, which manifests itself with less negative corrosion potential and lower corrosion and passivity currents in potentiodynamic curve, is promoted by the UIT induced oxide films and the following structural features: the CSL type of γ/ε interfacial boundaries, uniformly distributed fine carbides, and high fraction of the grains oriented with close packed (111)γ and (0002)ε planes parallel to the surface of the UIT-processed specimen.


Assuntos
Materiais Biocompatíveis/química , Ligas de Cromo/química , Corrosão , Dureza , Propriedades de Superfície , Ultrassom
17.
Biochim Biophys Acta ; 1573(1): 39-47, 2002 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-12383940

RESUMO

An original technique of use of two-phase polymer systems as an analytical research method is described. The technique is based on the absorbance change of two-phase systems in visible spectrum during formation of the phases. Dynamics of this process was demonstrated as the kinetic curves. Addition of studied objects (macromolecules or cells) to the two-phase system modified the shape of the kinetic curve, depending on their individual surface properties. The technique has the following advantages as compared with traditional procedures of the particle surface analysis with the help of two-phase polymer systems: examination of particles with partition coefficients approaching zero; multiple analyses of the same samples; use of interphase as a matrix for study of spontaneous formation of studied particle complexes. The opportunities of the technique were demonstrated in a series of previous authors' works.


Assuntos
Técnicas de Química Analítica/métodos , Substâncias Macromoleculares , Polímeros , Actinas/química , Animais , Distribuição Contracorrente , Dextranos , Emulsões , Eritrócitos/química , Cinética , Tamanho da Partícula , Polietilenoglicóis , Espectrofotometria , Propriedades de Superfície , Água
18.
Biochim Biophys Acta ; 1671(1-3): 18-25, 2004 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-15026141

RESUMO

In the present work, a simple technique is proposed to study the effects of native extracellular matrix (ECM) of one cell type on the properties of other cell types. It is based on a procedure in which, after cells of one type are removed from the substrate, cells of another type are seeded on the same substrate. To obtain preparations of native ECM, cells were removed from the substrate by 0.02% EDTA only, without any proteolytic enzymes. Cells were placed on coverslips in standard Petri dishes and incubated in a culture medium for a time sufficient for adhesion and spreading, but not long enough to undergo mitosis. Up to four coverslips per Petri dish can be incubated, and various combinations of ECM and cell types can be used in one dish. It is important, therefore, that the different "ECM-cell" combinations are present in the same culture medium. For evaluation of ECM effects, the area occupied by the cell on a substrate and the perimeter of the cell were measured, and frequencies of cell distribution were calculated according to these parameters.


Assuntos
Técnicas de Cultura de Células/métodos , Tamanho Celular , Matriz Extracelular/metabolismo , Animais , Carcinoma de Células Escamosas/metabolismo , Células Cultivadas , Meios de Cultura , Matriz Extracelular/química , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos
19.
Sci Rep ; 4: 7578, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-25524881

RESUMO

There are two types of intrinsic surface states in solids. The first type is formed on the surface of topological insulators. Recently, transport of massless Dirac fermions in the band of "topological" states has been demonstrated. States of the second type were predicted by Tamm and Shockley long ago. They do not have a topological background and are therefore strongly dependent on the properties of the surface. We study the problem of the conductivity of Tamm-Shockley edge states through direct transport experiments. Aharonov-Bohm magneto-oscillations of resistance are found on graphene samples that contain a single nanohole. The effect is explained by the conductivity of the massless Dirac fermions in the edge states cycling around the nanohole. The results demonstrate the deep connection between topological and non-topological edge states in 2D systems of massless Dirac fermions.

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