Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 149
Filtrar
1.
J Fish Biol ; 104(3): 564-575, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37927095

RESUMO

To investigate the stress response and physiological adaptations of goldfish (Carassius auratus) to critical salinity (CS) waters, we analyzed high-density lipoprotein (HDL) stoichiometry, stress markers (cortisol, glucose), and plasma osmotic properties (Na+ , osmolality, water content) using ichthyology, biochemistry, and proteomics approaches. After 21 days of exposure to CS, plasma concentrations of cortisol, glucose, and Na+ increased, indicating stress. Total plasma osmolality (Osmtotal ) and osmolality generated by inorganic (Osminorg ) and organic osmolytes (Osmorg ) also increased, the latter by ~2%. We associated the increase of Osmorg with (1) increased metabolite concentration (glucose), (2) dissociation of HDL particles resulting in increased HDL number per unit plasma volume (~1.5-2-fold) and (3) increased HDL osmotic activity. HDL remodeling may be the reason for the redistribution of bound and free water in plasma, which may contribute to water retention in plasma and, at the same time, to hemodynamic disturbances under CS conditions. The study's findings suggest that HDL remodeling is an important mechanism for maintaining osmotic homeostasis in fish, which is consistent with current capillary exchange models in vertebrates.


Assuntos
Carpa Dourada , Salinidade , Animais , Carpa Dourada/fisiologia , Lipoproteínas HDL , Hidrocortisona , Água/química , Glucose
2.
Dalton Trans ; 52(47): 18010-18017, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37986576

RESUMO

Pyridinium cesium cobalt nitrate, (PyH)CsCo2(NO3)6, obtained from a nitric acid solution crystallizes in the orthorhombic space group Pnma with unit cell parameters a = 8.6905(14) Å, b = 11.9599(18) Å, c = 18.386(3) Å, V = 1911.0(5) Å3, and Z = 4. It consists of [Co(NO3)3]- layers, in which each Co2+ ion is connected with four monodentate bridging NO3-groups and one bidentate terminal NO3-group, forming a corrugated rectangular net. Magnetization and specific heat measurements show that (PyH)CsCo2(NO3)6 undergoes a long-range canted antiferromagnetic ordering in two steps at TC1 = 5.0 K and TC2 = 2.6 K. The temperature dependence of the magnetic susceptibility and the field dependence of the magnetization measured for (PyH)CsCo2(NO3)6 show that it is an Ising antiferromagnet. In support of these observations, our DFT + U + SOC calculations show that the Co2+ ions of (PyH)CsCo2(NO3)6 have an easy-axis magnetic anisotropy with preferred spin orientation along the b-axis. To a first approximation, the spin lattice of (PyH)CsCo2(NO3)6 is a weakly alternating Ising antiferromagnetic chain (J1/J2 ∼ 0.85), and these chains interact weakly (J3/J2 ∼ 0.07) to form a rectangular Ising antiferromagnetic lattice. In agreement with the prediction for a rectangular Ising antiferromagnet by Onsager, (PyH)CsCo2(NO3)6 undergoes a long-range antiferromagnetic ordering.

3.
Phys Chem Chem Phys ; 25(37): 25526-25536, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37712871

RESUMO

The spatial spin modulated structure (SSMS) of the cycloid type present in bulk BiFeO3 prevents the linear magnetoelectric effect. One way to influence this structure is to reduce the crystal size to the nanoscale. Various opinions are circulating in the literature about the effect of nanocrystal size on SSMS, and to investigate this issue, we used a number of methods, with zero-field NMR (ZF NMR) spectroscopy at the forefront. ZF NMR spectroscopy enables the direct observation of the distribution profile of local fields on iron atoms and defines the SSMS presence and its properties. We also examined the synthesized samples using XRD, TEM, and magnetometry. We conclude that SSMS persists as the nanocrystal size decreases to the cycloid period and less, becoming more harmonic. This is accompanied by the change of the anisotropy type from an "easy axis" to an "easy plane". Magnetic measurements show a significant increase in the saturation magnetization, remanent magnetization, coercivity, and exchange bias of nanocrystals with sizes close to the cycloid period, which is probably associated with incomplete spin compensation in the case of an incomplete cycloid period. Despite the fact that SSMS is retained in the samples with decreased size, the magnetic properties experience a sharp increase up to applicable values.

4.
Dalton Trans ; 52(28): 9664-9672, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37381750

RESUMO

We prepared a new compound, Co3(SeO3)(SeO4)(OH)2, having layers in a kagomé-like arrangement of Co2+ (spin S = 3/2) ions. This phase crystallizes in the orthorhombic space group Pnma (62) with unit cell parameters a = 11.225(9) Å, b = 6.466(7) Å and c = 11.530(20) Å. Its layers, parallel to the ab-plane, are made up of Co1O5 square pyramids and Co2O6 and Co3O6 octahedra. As the temperature is lowered, Co3(SeO3)(SeO4)(OH)2 undergoes three successive magnetic transitions at 27.5, 19.4 and 8.1 K, and the magnetization of Co3(SeO3)(SeO4)(OH)2 measured at 2.4 K exhibits a 1/3-magnetization plateau between 7.8 and 19.9 T. The H-T magnetic phase diagram constructed for Co3(SeO3)(SeO4)(OH)2 from ac and dc magnetic susceptibility, specific heat and magnetization measurements contains three magnetic phases I, II and III. Phase I is antiferromagnetic, while phases II and III are ferrimagnetic and responsible for the 1/3-magnetization plateau. To interpret these complex magnetic properties, we identified the correct spin lattice for Co3(SeO3)(SeO4)(OH)2 by evaluating its intralayer and interlayer spin exchanges based on spin-polarized DFT+U calculations.

5.
Appl Radiat Isot ; 198: 110832, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37182393

RESUMO

Proton induced reaction data are needed in the optimization of various radioisotope production routes, among others. In this work, the evaluation of proton-induced reactions on 111Cd between 1 and 100 MeV using the TALYS code system within an iterative Bayesian Monte Carlo (iBMC) framework, is presented. The method involves the simultaneous variation of a large number of nuclear reaction models included in the TALYS code system as well as their parameters. Each random TALYS calculation yields a vector of calculated values of cross section observables as well as the angular distributions, among others, which were compared with corresponding vectors of carefully selected differential experimental data for reaction channels where data were available. The random nuclear data file with the maximum likelihood function value obtained from combining the individual χ2s computed for the considered reaction channels was chosen as the parent vector and the starting point for the generation of a further set of random TALYS calculations. This was repeated multiple times until a targeted convergence of 5% was reached. The final evaluated file was compared with available experimental data from the EXFOR database as well as with the evaluations from the TENDL-2021 and JENDL5.0 libraries, and found to compare favorably.


Assuntos
Braquiterapia , Cádmio , Prótons , Teorema de Bayes , Radioisótopos
6.
Dalton Trans ; 52(1): 118-127, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36468631

RESUMO

We prepared Cs2Cu3(SeO3)4·2H2O composed of Cu2+ ions at square-planar coordination sites and characterized its structural and magnetic properties, to show that Cs2Cu3(SeO3)4·2H2O is a ferrimagnet exhibiting a highly anisotropic 1/3-magnetization plateau. This unprecedented anisotropy in a magnetization plateau is the consequence of three effects, namely, the orthogonal arrangements of the corner-sharing CuO4 square planes, the nearest-neighbour antiferromagnetic exchange, and the anisotropic g-factor of the Cu2+ ions at square-planar coordination sites. By analyzing the topology of magnetic bonding, we found why magnetic plateaus are observed only for certain ferrimagnets and antiferromagnets.

7.
Artigo em Russo | MEDLINE | ID: mdl-36538399

RESUMO

The deterioration in the prognosis of coronary heart disease (CHD) is due to the influence of numerous pathophysiological factors, which is almost impossible to handle with only medication. Positive results obtained after one course of laser therapy (LT) in patients with angina pectoris substantiate the possibility of prolonging the effect when using repeated courses of low-intensity laser exposure. PURPOSE OF THE STUDY: To assess the clinical and prognostic value of repeated courses of low-intensity LT in patients with CHD for 24 months. MATERIAL AND METHODS: The study involved 40 men (mean age 56.6±8.2 years) with exertional angina pectoris with high (0-I functional class - 40%) and lower (II-III functional class - 60%) exercise tolerance (according to the classification of the Canadian Heart Association). Duration of the study was 24 months. All patients underwent 10-day courses of skin LT in the infrared radiation range every 6 months. Initially and after each course of LT, a bicycle ergometer test was performed with an assessment of the threshold values of blood pressure (BP), double product (DP=systolic BP×heart rate) and the ratio of DP to load power (DP/W). The blood levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were studied after each course of LT. RESULTS: Patients had an improvement in their well-being during LT: a decrease in the number of angina attacks, the need for nitroglycerin, antianginal and antihypertensive drugs. A statistically significant increase in exercise tolerance by 33.2-40.1% was revealed since 1 month after each course of LT, according to the results of stress tests. At the same time, the threshold values of blood pressure remained at the initial level, which was regarded as a manifestation of the hypotensive effect. The decrease in the DP/W index by 18.2-29.6% compared with the initial data indicates the energy economization of cardiac activity. LT was accompanied by a statistically significant decrease in blood cholesterol from 6.15±1.26 to 4.84±1.28-5.25±1.53 mmol/l and LDL-C from 4.70±1.16 to 3, 29±1.26-3.96 mmol/l. CONCLUSION: Long-term clinical and preventive effect, good tolerability, availability, absence of side effects substantiate the possibility of widespread use of repeated courses of laser exposure in coronary heart disease.


Assuntos
Doença das Coronárias , Masculino , Humanos , Pessoa de Meia-Idade , LDL-Colesterol/uso terapêutico , Prognóstico , Canadá , Angina Pectoris/tratamento farmacológico , Lasers
8.
Acta Naturae ; 14(3): 57-68, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36348712

RESUMO

Type 2 diabetes mellitus (T2DM) is the most common endocrine disorder (90%) in the world; it has numerous clinical, immunological, and genetic differences from type 1 diabetes mellitus. The pathogenesis of T2DM is complex and not fully clear. To date, animal models remain the main tool by which to study the pathophysiology and therapy of T2DM. Rodents are considered the best choice among animal models, because they are characterized by a small size, short induction period, easy diabetes induction, and economic efficiency. This review summarizes data on experimental models of T2DM that are currently used, evaluates their advantages and disadvantages vis-a-vis research, and describes in detail the factors that should be taken into account when using these models. Selection of a suitable model for tackling a particular issue is not always trivial; it affects study results and their interpretation.

9.
Dalton Trans ; 51(39): 15017-15021, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36112086

RESUMO

A mixed-valence compound Pb2Cu10O4(SeO3)4Cl7 has a complex structure consisting of one nonmagnetic Cu+ (S = 0) ion and four nonequivalent magnetic Cu2+ (S = 1/2) ions. It exhibits antiferromagnetic ordering at TN = 10.2 K. At a temperature below TN, a sequence of spin-flop transition at Bspin-flop = 1.3 T and 1/3 plateau formation at Bspin-flip = 4.4 K is observed in the magnetization curve M(B). The 1/3 magnetization plateau persists at least up to 53.5 T. The spin exchanges of Pb2Cu10O4(SeO3)4Cl7 evaluated by performing energy-mapping analysis based on DFT+U calculations show that the magnetic properties of Pb2Cu10O4(SeO3)4Cl7 are described by the (Cu2+)7 cluster of corner-sharing (Cu2+)4 tetrahedra, and that each (Cu2+)7 cluster has a S = 3/2 spin arrangement in the ground state. The 1/3 magnetization plateau observed for Pb2Cu10O4(SeO3)4Cl7 is explained by the field-induced flip of every second (Cu2+)7 cluster within a unit cell.

10.
Sci Rep ; 12(1): 7383, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513475

RESUMO

Single crystals of Cu[Formula: see text]Bi(SeO[Formula: see text])[Formula: see text]O[Formula: see text]Cl were investigated using high-resolution capacitance dilatometry in magnetic fields up to 15 T. Pronounced magnetoelastic coupling is found upon evolution of long-range antiferromagnetic order at [Formula: see text] [Formula: see text] K. Grüneisen analysis reveals moderate effects of uniaxial pressure on [Formula: see text], of 1.8(4) K/GPa, [Formula: see text] K/GPa and 0.33(10) K/GPa for [Formula: see text], b, and c, respectively. Below 22 K Grüneisen scaling fails which implies the presence of competing interactions. The structural phase transition at [Formula: see text] [Formula: see text] K is much more sensitive to uniaxial pressure than [Formula: see text], with strong effects of up to 27(3) K/GPa ([Formula: see text]). Magnetostriction and magnetization measurements reveal a linear magnetoelastic coupling for [Formula: see text] below [Formula: see text], as well as a mixed phase behavior above the tricritical point around 0.4 T. An analysis of the critical behavior in zero-field points to three-dimensional (3D) Ising-like magnetic ordering. In addition, the magnetic phase diagrams for fields along the main crystalline axes are reported.

11.
Artigo em Russo | MEDLINE | ID: mdl-35485655

RESUMO

The high prevalence of the combination of arterial hypertension (AH) with coronary heart disease (CHD) suggests the improvement of their treatment methods. In this regard, it is of interest to assess the dynamics of the clinical picture of patients against the background of pathogenetically determined subcellular and systemic changes under the influence of laser therapy (LT). OBJECTIVE: To evaluate the clinical effect of LT in patients with hypertension in combination with coronary artery disease and trace its relationship with the dynamics of the structure of the lipid bilayer of the erythrocyte membrane and changes in the microvascular bed. MATERIAL AND METHODS: We examined 65 male patients (mean age 50.9±6.3 years) with II-III degree AH in combination with coronary artery disease with angina pectoris. Among them, 40 patients received a 10-day course of LT, and 25 patients underwent simulated laser irradiation. At the initial stage and after 1 month, all patients underwent a bicycle exercise test, a study of the lipid composition of the erythrocyte membrane, including the main fractions of phospholipids and free cholesterol, as well as the level of intracellular Ca2+ and lipid peroxidation products - malondialdehyde and diene conjugates. Microcirculation was assessed using the method of conjunctival biomicroscopy. RESULTS: One month after the course of LT, patients showed a significant increase in exercise tolerance by 37.8%, a decrease in systolic blood pressure with a standard load by 9.9%. The improvement of the clinical picture occurred against the background of a decrease in the activity of lipid peroxidation and structural changes in the cell membrane: an increase in polyunsaturated fractions of phospholipids and a decrease in the cholesterol content, as well as a decrease in the Ca2+ level in the cell from 0.23 [0.19; 0.32] to 0.20 [0.16; 0.26] mmol/l. The results of the analysis of conjunctival biomicroscopy demonstrated a statistically significant decrease in the ratio of arteriolovenular calibers, a limitation of the severity of sludge syndrome by 59%, and an almost twofold (from 3.9±0.52 to 7.2±1.23 cap/mm2) increase in capillary density. CONCLUSION: The data obtained showed that in patients with hypertension in combination with coronary artery disease, LT causes positive changes in the lipid structure of the cell membrane and microcirculation parameters, which is accompanied by a hypotensive effect and an improvement in the clinical and functional state of patients.


Assuntos
Doença da Artéria Coronariana , Hipertensão , Terapia a Laser , Adulto , Colesterol/análise , Colesterol/metabolismo , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/metabolismo , Membrana Eritrocítica/química , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/efeitos da radiação , Feminino , Humanos , Hipertensão/complicações , Hipertensão/radioterapia , Masculino , Microcirculação , Pessoa de Meia-Idade , Fosfolipídeos/análise , Fosfolipídeos/metabolismo
12.
Histochem Cell Biol ; 157(1): 83-91, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34652540

RESUMO

Human infertility is a complex disorder at the genetic, molecular, cellular, organ, and hormonal levels. New developing technology based on the generation of human primordial germ cell-like cells (hPGCLCs) from induced pluripotent stem cells (hiPSCs) might improve understanding of early germ cell development (specification, migration, gametogenesis, and epigenetic reconstitutions), as well as offering a solution for infertility and hereditary disorders. In this study, we differentiated hiPSCs with trisomy 21 into hPGCLCs. In vitro-derived germ cells from hiPSCs with Down syndrome (DS) express hPGCLC core circuitry, EOMES, SOX17, and PRDM14 at relatively low levels. TFAP2C and PRDM1 were expressed and remained elevated, whereas NANOS3 and NANOG were downregulated in BMP4-induced hiPSCs with DS. The low level of NANOG and NANOS3 expression might negatively influence hPGCLC generation in DS hiPSCs. We suggest that DS hPGCLCs could be a suitable model for studying human early germ cell development, the epigenetic and molecular mechanisms of PGC specification and formation, as well as related infertility disorders, such as azoospermia and teratozoospermia.


Assuntos
Síndrome de Down , Células-Tronco Pluripotentes Induzidas , Diferenciação Celular/genética , Síndrome de Down/genética , Síndrome de Down/metabolismo , Regulação para Baixo , Células Germinativas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo
13.
Phys Rev E ; 104(5-2): 055203, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34942734

RESUMO

Resonances with electromagnetic whistler-mode waves are the primary driver for the formation and dynamics of energetic electron fluxes in various space plasma systems, including shock waves and planetary radiation belts. The basic and most elaborated theoretical framework for the description of the integral effect of multiple resonant interactions is the quasilinear theory, which operates through electron diffusion in velocity space. The quasilinear diffusion rate scales linearly with the wave intensity, D_{QL}∼B_{w}^{2}, which should be small enough to satisfy the applicability criteria of this theory. Spacecraft measurements, however, often detect whistle-mode waves sufficiently intense to resonate with electrons nonlinearly. Such nonlinear resonant interactions imply effects of phase trapping and phase bunching, which may quickly change the electron fluxes in a nondiffusive manner. Both regimes of electron resonant interactions (diffusive and nonlinear) are well studied, but there is no theory quantifying the transition between these two regimes. In this paper we describe the integral effect of nonlinear electron interactions with whistler-mode waves in terms of the timescale of electron distribution relaxation, ∼1/D_{NL}. We determine the scaling of D_{NL} with wave intensity B_{w}^{2} and other main wave characteristics, such as wave-packet size. The comparison of D_{QL} and D_{NL} provides the range of wave intensity and wave-packet sizes where the electron distribution evolves at the same rates for the diffusive and nonlinear resonant regimes. The obtained results are discussed in the context of energetic electron dynamics in the Earth's radiation belt.

14.
Dalton Trans ; 50(39): 13815-13822, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34519734

RESUMO

Synthesis and characterization of structure and magnetic properties of the quasi-octahedral complex (pipH2)[Co(TDA)2] 2H2O (I), (pipH22+ = piperazine dication, TDA2- = thiodiacetic anion) are described. X-ray diffraction studies reveal the first coordination sphere of the Co(II) ion, consisting of two chelating tridentate TDA ligands with a mixed sulfur-oxygen strongly elongated octahedral coordination environment. SQUID magnetometry, frequency-domain Fourier-transform (FD-FT) THz-EPR spectroscopy, and high-level ab initio SA-CASSCF/NEVPT2 quantum chemical calculations reveal a strong "easy-plane" type magnetic anisotropy (D ≈ +54 cm-1) of complex I. The complex shows field-induced slow relaxation of magnetization at an applied DC field of 1000 Oe.

15.
Zh Nevrol Psikhiatr Im S S Korsakova ; 121(7. Vyp. 2): 31-36, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34387443

RESUMO

As the COVID-19 pandemic continues, reducing the risk of infection for immunocompromised patients remains an important issue. Patients with aggressive multiple sclerosis (MS) require immunosuppressive therapy in order to control the overactive autoimmune response. Preliminary international and national trials demonstrate that older age, higher disability status and progressive MS are generally associated with a more severe clinical course of COVID-19. However, uncertainty remains about the effect of disease-modifying therapies on the COVID-19 clinical presentation. In this article, we pay special attention to monoclonal antibodies used for immune reconstitution therapy, which results in significant changes to the T-cell and/or B-cell repertoire. Based on the published data from registries in different countries, we attempted to estimate the benefits and risks of these therapies in a complicated epidemiological setting.


Assuntos
COVID-19 , Esclerose Múltipla , Idoso , Anticorpos Monoclonais/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/epidemiologia , Pandemias , SARS-CoV-2
16.
Sci Rep ; 11(1): 15002, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294799

RESUMO

Uniform quasi-one-dimensional integer spin compounds are of interest as a potential realization of the Haldane conjecture of a gapped spin liquid. This phase, however, has to compete with magnetic anisotropy and long-range ordered phases, the implementation of which depends on the ratio of interchain J' and intrachain J exchange interactions and both uniaxial D and rhombic E single-ion anisotropies. Strontium nickel selenite chloride, Sr2Ni(SeO3)2Cl2, is a spin-1 chain system which passes through a correlations regime at Tmax ~ 12 K to long-range order at TN = 6 K. Under external magnetic field it experiences the sequence of spin-flop at Bc1 = 9.0 T and spin-flip transitions Bc2 = 23.7 T prior to full saturation at Bsat = 31.0 T. Density functional theory provides values of the main exchange interactions and uniaxial anisotropy which corroborate the experimental findings. The values of J'/J = 0.083 and D/J = 0.357 place this compound into a hitherto unoccupied sector of the Sakai-Takahashi phase diagram.

17.
Vestn Oftalmol ; 137(3): 76-84, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34156781

RESUMO

PURPOSE: To study the capabilities of high-speed spectral-domain optical coherence tomography angiography (SD-OCTA) with image averaging in the evaluation of choriocapillaries in healthy individuals and patients with central serous chorioretinopathy (CSC). MATERIAL AND METHODS: All participants underwent OCTA examination on the SOLIX tomograph (Optovue, USA) using quadruplicate 3×3 mm scan with image averaging. Image analysis was performed in 9-µm custom slab with Phansalkar auto local threshold algorithm and calculation of flow voids larger than 5000 µm2 and 10 000 µm2. The optimal slab depth was determined in healthy eyes by consecutive analysis of the slabs with a 3-µm shift from zero position to 33 µm below Bruch's membrane. RESULTS: The study included 18 eyes of 18 healthy volunteers (40.4±6.0 years old) and 18 fellow eyes of 18 unilateral CSC patients (37.4±10.7 years old). The slab 12 µm below the Bruch's membrane showed the minimal number of flow voids (23.1±7.0 of >5000 µm2 voids per scan) and was chosen for further analysis. The number of flow voids of >5000 µm2 in healthy paired eyes of CSC patients was statistically significantly higher than in the eyes of healthy individuals (32.7±10.7 and 25.3±8.1 voids/scan, respectively; p=0.022). The number of flow voids of >10000 µm2 was also statistically significantly higher in CSC eyes compared to healthy eyes (5.6±3.3 and 3.5±1.9 voids/scan, respectively; p=0.045). There was no statistically significant difference in total area of the voids between the eyes of healthy individuals and CSC patients (96406.1±3924.5 µm2 and 95395.7 ± 3615.1 µm2, respectively; p=0.42). CONCLUSION: The optimal settings for choriocapillaris imaging on the SOLIX tomograph include 9-µm slab 9 to 18 µm below the Bruch's membrane. Using a 9-µm slab 12 µm below the Bruch's membrane, a substantial difference was found in choriocapillaris perfusion between eyes of healthy individuals and CSC patients.


Assuntos
Coriorretinopatia Serosa Central , Tomografia de Coerência Óptica , Adulto , Lâmina Basilar da Corioide/diagnóstico por imagem , Coriorretinopatia Serosa Central/diagnóstico por imagem , Corioide/diagnóstico por imagem , Angiofluoresceinografia , Humanos , Pessoa de Meia-Idade
18.
Dokl Biochem Biophys ; 496(1): 5-9, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33689065

RESUMO

A new stable line of human keratinocytes was obtained. The cells have altered morphology, both abnormal chromosomal composition and expression of keratinocyte markers, do not show contact inhibition, could be cultured in various media and have limited stratification ability in vitro. Upon transplantation into nude mice the cells have tumorigenic properties.


Assuntos
Transformação Celular Neoplásica/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Telomerase/metabolismo , Animais , Domínio Catalítico , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Aberrações Cromossômicas , Xenoenxertos , Humanos , Queratinócitos/enzimologia , Masculino , Camundongos , Camundongos Nus , Cultura Primária de Células , Telomerase/genética
19.
Sci Rep ; 11(1): 2084, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483553

RESUMO

The fusion power density produced in a tokamak is proportional to its magnetic field strength to the fourth power. Second-generation high temperature superconductor (2G HTS) wires demonstrate remarkable engineering current density (averaged over the full wire), JE, at very high magnetic fields, driving progress in fusion and other applications. The key challenge for HTS wires has been to offer an acceptable combination of high and consistent superconducting performance in high magnetic fields, high volume supply, and low price. Here we report a very high and reproducible JE in practical HTS wires based on a simple YBa2Cu3O7 (YBCO) superconductor formulation with Y2O3 nanoparticles, which have been delivered in just nine months to a commercial fusion customer in the largest-volume order the HTS industry has seen to date. We demonstrate a novel YBCO superconductor formulation without the c-axis correlated nano-columnar defects that are widely believed to be prerequisite for high in-field performance. The simplicity of this new formulation allows robust and scalable manufacturing, providing, for the first time, large volumes of consistently high performance wire, and the economies of scale necessary to lower HTS wire prices to a level acceptable for fusion and ultimately for the widespread commercial adoption of HTS.

20.
Ter Arkh ; 92(6): 33-36, 2020 Jul 09.
Artigo em Russo | MEDLINE | ID: mdl-33346490

RESUMO

AIM: Determine whether bone mineral density (BMD) assessed by dual-energy x-ray absorptiometry can be used as predictor of increased risk of death in hemodialysis patients. MATERIALS AND METHODS: A prospective study was performed of 516 patients with chronic kidney disease treated with hemodialysis (men 265, women 251, mean age 44.811.4 years) who were observed for 5.73.2 years. Before inclusion in the study, in all patients was analyzed bone mineral density using dual-energy X-ray absorptiometry in three standard departments: lumbar vertebrae, proximal femur and distal forearm. The probability analysis of the outcome was carried out using the KaplanMeier method and Cox. RESULTS: During follow-up period 111 (21.5%) patients died, 50.5% from cardiovascular events. Survival analysis by KaplanMeier method allowed to prove the increased risk of death from cardiovascular pathology in hemodailysis patients with low bone mineral density of all evaluated areas. Step-by-step multivariate Cox regression analysis showed that the T score of the femur, showing the difference of BMD of the patient with normal value of BMD for young adult, had the greatest prognostic significance. CONCLUSION: Reduced bone mineral density in patients receiving hemodialysis is associated with an increased risk of death from cardiovascular disease. Dual energy x-ray absorptiometry can be used for assessment of this risk.


Assuntos
Doenças Cardiovasculares , Osteoporose , Absorciometria de Fóton , Adulto , Densidade Óssea , Doenças Cardiovasculares/diagnóstico por imagem , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Osteoporose/diagnóstico por imagem , Estudos Prospectivos , Diálise Renal , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...