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The boson peak in the terahertz vibrational spectrum carries information about nano-heterogeneities in the shear modulus in glass formers. Its evolution upon heating or cooling in a supercooled liquid state may shed light on the temperature dependence of heterogeneities. For this purpose, an analysis of the light scattering spectra of supercooled glycerol in the spectral range of the boson peak and fast relaxation was carried out and the parameters of the boson peak in the temperature range 180-330 K were determined. The temperature dependent frequency of the boson peak was then expressed in terms of the mean-square amplitude of the shear modulus fluctuations. This was done using the heterogeneous elasticity theory in combination with the perturbation theory on small fluctuations and Ioffe-Regel criterion for transverse vibrations in glass formers. The contribution of structural relaxation effects to phonon damping becomes significant with increasing temperature. It is shown here that structural relaxation largely determines the temperature dependence of the mean-square fluctuations of the shear modulus at high temperatures. By solving the inverse problem, the temperature dependence of shear modulus fluctuations was obtained. It shows a rapid decrease above â¼250 K with a linear extrapolation going to zero at the so-called Arrhenius temperature TA = 350 K. Comparison with literature data on the Landau-Placzek ratio shows that they have a similar temperature dependence at T < TA, which is explained by the appearance of nanometer scale spatial heterogeneities below TA. This is confirmed by the temperature dependence of the amplitude of the boson peak.
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Optical applications based on fast and slow light effects force the usage of metamaterials famous for their flexible dispersion properties. In this work, we apply the unique optical nonlocality of metal nanorod-based epsilon-near-zero (ENZ) metamaterials along with the chirp of femtosecond laser pulses for astonishing control of these effects. We demonstrate the switching between the fast and slow light phenomena via the change of the angle of incidence and/or the central wavelength of chirped pulses in the vicinity of metamaterial zero-transmission regime mediated by the ENZ nonlocality. We elucidate that the laser chirp allows one to manipulate and enhance the fast-slow light phenomena.
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In this work, we study two series of the copolymers of L-lactide (LLA) and ε-caprolactone (CL) with the CL molar content of 5, 15, and 30 %. The first series was the commercial semicrystalline granules (Corbion, Netherlands), which we analyzed without any additional modification. The second series was amorphous films, prepared from the granules by hot pressing with the subsequent fast quenching in order to avoid the crystallization. We used Raman spectroscopy in conjunction with the quantum chemical modeling to evaluate the structure of the copolymers. As additional methods, we applied X-ray diffraction (XRD) analysis and differential scanning calorimetry (DSC). The main result of our study is the elaboration of the Raman methods of quantitative analysis of the relative contents of the comonomers and the crystallinity degree of the poly(L-lactide-co-ε-caprolactone). These methods are based on measurements of the ratios of the peak intensities of the poly(L-lactide) (PLLA) bands at 411 and 874 cm-1, the PLLA band at 2947 cm-1 and the poly(ε-caprolactone) band at 2914 cm-1. Raman study shows that growth of the CL content causes the monotonous decrease in the crystallinity degree of PLLA blocks. Density functional theory analysis of LLA decamer in the conformation of helix 103 allows us to assign the PLLA Raman bands. The Raman data on the composition and crystallinity degree of the copolymers correlate very well with the results of XRD and DSC studies, as well as with the information on the composition of the copolymers provided by manufacturer.
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We performed a comparative study of the parameters of chemiluminescence of blood neutrophils in patients with different severity of chronic obstructive pulmonary disease in its different periods. The maximum values of induced and spontaneous chemiluminescence were recorded at moderate severity of the disease during exacerbation. Low levels of chemiluminescence indicators were found in severe chronic obstructive pulmonary disease in the stable phase. The values of the induction period of the chemiluminescent response in patients with moderate chronic obstructive pulmonary disease were higher than in the control group. Correlations between the values of induced chemiluminescence of neutrophils and the respiration function parameter FEV1 were established, which may indicate the influence of multidirectional changes in the functional activity of systemic neutrophils on the development and worsening of airway obstruction in chronic obstructive pulmonary disease patients.
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Neutrófilos , Doença Pulmonar Obstrutiva Crônica , HumanosRESUMO
INTRODUCTION: Four terbium isotopes 149,152,155,161Tb emitting various types of radiation can be used for both diagnostics and therapy. 152Tb emits positrons and is ideal for PET. 155Tb is considered a promising Auger emitter and a diagnostic pair for other terbium therapeutic isotopes. Several methods for the production of 155Tb using charged particle accelerators have been proposed, but they all have significant limitations. The restricted availability of this isotope hinders its medical applications. We have proposed a new method for production of 155Tb, irradiating enriched 155Gd by alpha particles. The possibility of simultaneous production of two isotopes of terbium, 152,155Tb, was also studied for more efficient cyclotron beam use. METHODS: Irradiation of 155Gd enriched targets and 155Gdâ¯/â¯151Eu tandem target with alpha-particles with an energy of 54â¯MeV was carried out at the U-150 cyclotron at the NRC "Kurchatov Institute". The cross sections of nuclear reactions on enr-155Gd were measured by the stack foil technique, detecting the gamma-radiation of the activation products. The separation of rare earth elements was performed by extraction chromatography with the LN Resin. 155Tb was produced via 155Dy decay. RESULTS: The cross sections for the 155,156Tb and 155,157Dy production were measured by the irradiation of a gadolinium target enriched with the 155Gd isotope with alpha-particles in an energy range of 54â¯ââ¯33â¯MeV. The yield of 155Dy on a thick target at 54â¯MeV was 130â¯MBq/µAh, which makes it possible to obtain 1â¯GBq of 155Tb in 11â¯hour-irradiation with 20⯵A beam current. The possibility of simultaneous production of 152,155Tb by irradiation of 155Gd and 151Eu tandem target with medium-energy alpha-particles is implemented. Optimal irradiation energy ranges of alpha -particles as 54â¯ââ¯42â¯MeV for 155Tb and 42â¯ââ¯34â¯MeV for 152Tb were suggested. Product activity and radionuclidic purity were calculated.
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Partículas alfa , Térbio , Térbio/química , Partículas alfa/uso terapêutico , Radioisótopos/química , ElétronsRESUMO
OBJECTIVE: To determine the features of preoperative hemostatic therapy and laboratory control in patients with severe and inhibitory forms of hemophilia A under preventive treatment by FVIII. MATERIAL AND METHODS: Four patients with severe and inhibitory forms of hemophilia A underwent surgery between 2021 and 2022. All patients received Emicizumab (the first monoclonal drug for «non-factor¼ therapy of hemophilia) for prevention of specific hemorrhagic signs of hemophilia. RESULTS: Surgical intervention under preventive Emicizumab therapy was essential. Additional hemostatic therapy was not carried out or performed in reduced mode. There were no hemorrhagic, thrombotic or other complications. Thus, the so-called «non-factor¼ therapy is one of the variants for uncontrollable hemostasis in patients with severe and inhibitory forms of hemophilia. CONCLUSION: Preventive injection of Emicizumab ensures certain buffer of hemostasis system and stable lower limit of coagulation potential. This is the result of stable concentration of Emicizumab when used in any of the registered forms regardless of age and other individual characteristics. The risk of acute severe hemorrhage is excluded, while the probability of thrombosis is not increased. Indeed, FVIII has higher affinity than Emicizumab and displaces Emicizumab from coagulation cascade that does not result summation of total coagulation potential.
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Anticorpos Biespecíficos , Hemofilia A , Hemostáticos , Trombose , Humanos , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Hemorragia/prevenção & controle , Hemorragia/complicações , Coagulação Sanguínea , Anticorpos Biespecíficos/efeitos adversos , Trombose/complicações , Hemostáticos/uso terapêutico , Fator VIII/efeitos adversosRESUMO
Optical vortices have myriad applications in photonics. Very recently, promising concepts of spatiotemporal optical vortex (STOV) pulses based on the phase helicity in the space-time coordinates have attracted much attention owing to their donut shape. We elaborate on the molding of STOV under the transmission of femtosecond pulses through a thin epsilon-near-zero (ENZ) metamaterial slab based on a silver nanorod array in a dielectric host. At the heart of the proposed approach is the interference of the so-called main and additional optical waves enabled by strong optical nonlocality of these ENZ metamaterials, which leads to the appearance of phase singularities in transmission spectra. The cascaded metamaterial structure is proposed for high-order STOV generation.
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The course of bronchial asthma can be accompanied by cognitive impairments. However, the relationship between cognitive dysfunction and asthma has not been fully revealed, nor has it been fully established what causes cognitive impairments in patients with asthma. There is an opinion that transient hypoxia and persistent systemic inflammation with insufficient control of bronchial asthma can be accompanied by neurotoxicity in relation to the hippocampus and indirectly lead to deterioration of cognitive functions. Comorbid conditions, such as obesity, allergic rhinitis, and depressive states can increase cognitive dysfunction in asthmatics. The review considers the pathophysiology of cognitive dysfunction in patients with bronchial asthma, as well as the impact of comorbid conditions on the cognitive status. This information will allow systematizing the available knowledge about the state of cognitive functions in asthma for timely detection and correction of their impairments and, ultimately, optimization of the management of these patients.
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Asma , Disfunção Cognitiva , Humanos , CogniçãoRESUMO
This is the first report on the physicochemical properties of chitin obtained from gills of the king crab Paralithodes camtschaticus. In the present study, we investigated the chemical composition of red king crab gills and considered methods of its complex processing to obtain chitin and enzymatic protein hydrolysates. The gills contained approximately 21 % chitin in terms of dry matter. For the first time, the gills of the king crab were investigated as a source of chitin and chitosan. Chitin was isolated from crab gills using chemical and enzymatic methods. The physicochemical properties of chitin and chitosan from the gills were investigated. By performing infrared spectroscopy and X-ray phase analyses, the chitin present in the gills was established to be α-chitin. The physical and chemical properties (degree of deacetylation, molecular weight and crystal structure) of gill chitin and chitosan were absolutely similar to those of crab shell. Crab gills can be used as an additional source of chitin in the integrated processing of king crabs. The yield of chitin from the gills is up to 45 % of the yield of chitin from the crab carapace.
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Anomuros , Quitosana , Animais , Quitosana/química , Quitina/química , Anomuros/metabolismo , Brânquias/metabolismo , Hidrolisados de ProteínaRESUMO
Raman spectra of ethylene glycol (EG) and 1,3-propylene glycol (1,3-PG) aqueous solutions with the diol content from 10 to 90 mol% were measured. The diol content weakly influences the EG and 1,3-PG Raman bands in the spectra of the solutions in the region 250-1800 cm-1. This fact means that the conformational compositions of both the diols do not change significantly with dissolving in water. The intensity of the OH stretching band with respect to the diol bands intensities is the linear function of the ratio of the mole contents of water and the diol in the solutions. The spectral region 2800-3800 cm-1 can be used to evaluate the chemical composition of these binary solutions. DFT modeling of the Raman spectra of EG molecule in water shell confirms the prevalence of the gauche-conformation of EG in the aqueous solutions.
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Etilenoglicol , Análise Espectral Raman , Análise Espectral Raman/métodos , Água/química , Conformação Molecular , Propilenoglicol , Soluções/químicaRESUMO
In patients with chronic obstructive pulmonary disease, the levels of cytokines IL-1ß, IL-4, IL-8, TNFα, and IFNγ depended on the degree of bronchial obstruction and severity and period of the disease. The maximum levels of IL-4, IL-8, and TNFα were observed in severe chronic obstructive pulmonary disease during exacerbation. The highest concentration of IL-1ß and IFNγ were recorded during activation of inflammation in patients with moderate bronchial obstruction. The revealed correlations between the tested cytokines and spirometry parameters make it possible to consider the levels of these proteins as quantitative markers of systemic inflammation progression.
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Doença Pulmonar Obstrutiva Crônica , Fator de Necrose Tumoral alfa , Humanos , Citocinas , Inflamação , Interferon gama/genética , Interleucina-4 , Interleucina-8/genética , Fator de Necrose Tumoral alfa/genéticaRESUMO
It is shown that the normalized rms fluctuation of the shear modulus on the medium-range order scale in glasses correlates with fragility: the higher fragility, the smaller the fluctuation amplitude. The latter is calculated within the heterogeneous elasticity theory using the data on the boson peak in glasses. On a smaller scale corresponding to cooperative structural relaxation, the normalized rms fluctuation of the infinite-frequency shear modulus was estimated using the data on the decoupling of viscosity and diffusion in supercooled liquids. These fluctuations are much smaller in amplitude, and, in contrast, they increase with increasing fragility. Extrapolation predicts intersection of both rms fluctuations and disappearing of the boson peak at the upper limit to fragility ≈180.
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In this work demostrates a unique method for determining the absolute value of the friction force of a nanoobject on the surface of a cell membrane using atomic force microscopy. The tribological properties of membranes of adult human buccal epithelium cells in the presence of a protective adsorption buffer layer of ~ 100 nm on their surface were studied using atomic force microscopy in the contact scanning mode. Local mapping of the tribological characteristics of the surface was carried out, viz. friction FL = FL(x, y) and adhesion Fadh = Fadh(x, y) forces were measured. Studies of the friction force Ffr on the membrane surface at the nanolevel showed that its value varies discretely with an interval equal to lLF ≈ 100 nm. It was shown that such discreteness is determined by the interval lLF of the action of adhesive forces Fadh and indicates the fractal nature of the functional dependence of the friction force on the coordinate Ffr = Ffr(x). Thus, for nano-objects with dimensions ≤ lLF, the absolute value of Ffr decreases according to a power law with an increase in the size of the object, which contradicts the similar dependence of the friction force for macro-objects in the global approximation.
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Membrana Celular , Adulto , Epitélio , Fricção , Humanos , Membranas , Microscopia de Força AtômicaRESUMO
INTRODUCTION: 155Tb (T1/2 = 5.32 d) is considered both as a promising Auger electron emitter and as a diagnostic pair for other therapeutic terbium radionuclides. Despite several methods for its production proposed, it remains scarcely available. Most of the methods using low-energy protons and deuterons beams result in a high content of radionuclidic impurities. High purity 155Tb can be obtained using high-energy proton beams combined with online mass separation of products, but the method remains inaccessible to most potential consumers. We have proposed an indirect method for the production of 155Tb via formation of 155Dy (T1/2 = 9.9 h), which can be implemented using medium energy alpha particles beam. METHODS: Gadolinium oxide targets of natural isotopic composition were irradiated by 60 MeV alpha particles beam on a U-150 cyclotron of the National Research Center "Kurchatov Institute". The cross sections of nuclear reactions were measured by the stack foil technique, detecting the gamma radiation of the activation products. Gd, Tb, and Dy were separated by extraction chromatography using the LN Resin sorbent in nitric media. The isolated dysprosium fraction was stored for a day, and the formed 155Tb was isolated by the same method. RESULTS: The cross sections for the formation of 159Gd, 153-156Tb, and 155,157Dy under irradiation by alpha particles of a gadolinium target of natural isotopic composition in the energy range 20-60 MeV have been measured. The 155Dy yield on a thick target at 60 MeV was 35 MBq/µAh, which makes it possible to obtain 1 GBq 155Tb as a result of 12-hour irradiation with a beam current of 50 µA. Extraction chromatography on LN Resin sorbent in nitric enabled quick and efficient separation of Gd, Tb, and Dy. The radiochemical yield of Dy was 95%, for Tb > 95%. The main radionuclidic impurity is 153Tb (T1/2 = 2.34 d; <5.4% of 155Tb activity). CONCLUSIONS: The developed method allows the production of therapeutic amounts of 155Tb with acceptable radionuclidic purity without the need for isotopically enriched materials. The amount of 155Tb is sufficient for its use in Auger therapy, as well as for preclinical studies of the suitability of SPECT preparations in laboratory animals. Nevertheless, to obtain higher activities, a longer irradiation time and a higher projectile current are proposed. The 153Tb radionuclide present in the final preparation has a shorter half-life than the target radionuclide, and its hard γ-lines have a probability of emission of less than 1%, from which it can be concluded that the negative effect will not be significant. However, a product of this purity and type of contamination requires additional testing for toxicity in living organisms. The final sample also includes a certain amount of 157Tb (T1/2 = 71 a, the only γ-line 54.5 keV Iγ = 0.0084%), which will complicate the labeling conditions. Thus, more research is needed in the labeling area. It should be noted that the use of gadolinium enriched in the 155Gd or 156Gd nuclide as a target will help not only reduce the amount of impurities but also increase the yield of 155Tb.
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Partículas alfa , Radioisótopos , Partículas alfa/uso terapêutico , Animais , Ciclotrons , Radioquímica/métodos , Radioisótopos/química , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/químicaRESUMO
Using the density functional theory (DFT), we calculated the structures and Raman spectra of trans-isomers of α-carotene, ß-carotene, γ-carotene and lycopene as well as trans-isomers of modified ß-carotene and lycopene molecules with substituted end or/and side groups. The DFT calculations showed that the position of the CC stretching band depends mainly on the number of conjugated CC bonds and decreases with an increase in the conjugation length. The weak dependence of the position of the CC stretching band on the structure of the carotenoid side and end groups suggests that this band can be used to evaluate the conjugation length for trans-isomers of various molecules containing polyene chains. The CC stretching band shifts towards lower wavenumbers with growth of the conjugation length or masses of the end groups and to higher wavenumbers in the presence of the side CH3 groups. The intensities of the CC and CC stretching bands are enhanced with growth of the conjugation length or masses of the end groups. The presence of the side CH3 groups results in bending of the carotenoid backbone, splitting and dumping of intensities of the CC and CC stretching bands.
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Análise Espectral Raman , beta Caroteno , Carotenoides , Licopeno , Estrutura MolecularRESUMO
The aim of the study was to assess the capabilities of mRNA genes encoding CD16a (FCGR3A) and CD16b (FCGR3B) in tumor samples from patients with renal cancer, and characterize the tumor process in relation to clinical and morphological factors. Materials and Methods: We used 125 tumor samples from patients with a histologically confirmed diagnosis of renal cancer T1-4N0-1M0-1. A method described by Chomczynski and Sacchi was used to isolate nucleic acids. The mRNA levels were determined using a reverse transcription polymerase chain reaction and calculated according to ΔΔCt formula, taking into account the reaction efficiency. Results: mRNA of the FCGR3A gene was detected in all tumor tissue samples under study; in contrast, mRNA of the FCGR3B gene was found only in 92.0% (115/125) of cases. In tumors classified as pT1, the mRNA content of the FCGR3A gene was significantly lower than that in tumor samples of pT3 size. There was the significant increase in the mRNA content of both genes with an increase in tumor grade, as well as in the cases with distant metastases. The presence of a tumor thrombus in the inferior vena cava system was accompanied by a significant increase in the mRNA content of the FCGR3A gene. Conclusion: In tumor tissue samples from patients with clear cell renal cancer, the predominant production of the FCGR3A mRNA was observed in comparison with the FCGR3B mRNA. The revealed relationship of an increased amount of the FCGR3A mRNA and, in some cases, the FCGR3B mRNA with a number of clinical and morphological factors enables to consider the mRNA level of the genes as new monitoring biomarkers.
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Carcinoma de Células Renais , Predisposição Genética para Doença , Humanos , Projetos Piloto , Carcinoma de Células Renais/genética , Receptores de IgG/genética , Proteínas Ligadas por GPI/genéticaRESUMO
INTRODUCTION: Enterovirus (nonpolio) infection is widespread all over the world, registered as sporadic cases and large-scale outbreaks and can cause severe lesions such as serous meningitis. Epidemiological studies have shown that enterovirus (Picornaviridae; Enterovirus) variant Echovirus 30 (E30) is the most frequently detected variant in patients with enterovirus meningitis in the Russian Federation. However, no vaccines to prevent the disease caused by this pathogen have been developed so far. One of the promising modern trends in terms of creating vaccine preparations is the use of virus-like particles (VLPs), including chimeric ones containing the biological structures of viruses belonging to different species.The aim of this work was to obtain norovirus (Caliciviridae; Norovirus) VLPs displaying enterovirus Echovirus E30 full-length VP1 on the surface. MATERIAL AND METHODS: The nucleotide sequences of VP1 protein of norovirus genotype GII.4 and VP1 E30 of genotype h circulating in Russia were used. The SN-VP1E30 protein was constructed, in which the shell (S) and the hinge regions of the norovirus VP1 are fused into one molecule with the full-length VP1 of the E30 virus. The protein was expressed in E. coli, purified using affinity chromatography, and characterized by polyacrylamide gel electrophoresis (PAGE) and immunoblotting. VLPs were visualized by electron microscopy. RESULTS: The S N-VP1E30 protein expressed in E. coli as insoluble form, so the conditions for SN-VP1E30 solublisation were defined. Sucrose has been shown to significantly increase the efficiency of renaturation. Electrophoretic mobility comparison of denatured and non-denatured SN-VP1E30 demonstrated that most monomers form high molecular weight compounds. Electron microscopy showed that renatured SN-VP1E30 spontaneously forms empty virus-like particles about 50 nm in diameter. CONCLUSION: Chimeric protein SN-VP1E30 self-assemble into VLPs displaying the VP1 protein of E30 variant that is highly prevalent in Russia. Further immunological research is necessary to characterize VLPs potential for development of the vaccine for enteroviral meningitis prevention.
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Caliciviridae , Enterovirus , Norovirus , Picornaviridae , Enterovirus/genética , Enterovirus Humano B , Escherichia coli , Humanos , Norovirus/química , Norovirus/genéticaRESUMO
The article presents the results of pilot study implemented to determine cognitive disorders in patients taking "Spice". The purpose of research is to identify targets of psychological correction interventions to prevent cognitive deficiency in patients addicted to synthetic cannabinoids. The pilot sampling consisted of 30 patients taking "Spice". The control group consisted of 30 healthy individuals. Along with social consequences, one of the important focuses of the study was investigation of cognitive sphere of patients. A number of pathopsychologic tests was applied. The study established that patients demonstrated disorders of various functions of memory, attention, mental pace and thinking. In particular, disorders of short-term, long-term and mediate memory and mental tempo were revealed. Also, reduced activity of attention took place. The distortion and decreasing of generalization and poor prehension occurred reliably more often as compared with control group. The established cognitive disorders in patients taking "Spice" can be considered as targets for psychological correction interventions to prevent cognitive deficiency in patients addicted to synthetic cannabinoids.
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Canabinoides , Transtornos Cognitivos , Cognição , Humanos , Projetos Piloto , Problemas SociaisRESUMO
The article considers various mental reactions of psychiatrists and narcologists against the background of the SARS-CoV-2 pandemic, based on a brief scientific analysis of publications and experimental psychological research methods. The purpose of study was to identify impact of the COVID-19 pandemic on mental health of psychiatrists and psychiatrists-narcologists. The results of survey of psychiatrists and narcologists are presented. The study was carried out using such test techniques as life quality scale SF-36 (Health Status Survey), Lazarus questionnaire "Coping Behaviors" adjusted to conditions of Russia and Hamilton scales to assess depression and anxiety (HDRS, HARS). The results.The low level of psychological well-being, moderate degree of preference for all coping strategies were established. The anxiety was determine in 34.8% of respondents and depression in 8.7%. It was established that actually, the impact of the COVID-19 pandemic on medical workers is conditioned by complex of mental reactions (from anosognosia to expressed anxiety and depressive disorders) and is accompanied by increasing general anxiety.
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COVID-19 , Pessoal de Saúde/psicologia , Estresse Psicológico , COVID-19/psicologia , Depressão/epidemiologia , Humanos , Pandemias , PsiquiatriaRESUMO
We studied the influence of combined preconditioning (compound pQ-4 and moderate hypoxia) on morphometrical parameters of neuronal populations in hippocampal fields CA1 and CA3 in rats after bilateral ligation of the common carotid artery. Preconditioning produced a neuroprotective effect, improved survival of pyramidal neurons in the early and delayed periods of modeled ischemia, prevented the formation of necrotic and apoptotic neurons and hyperactivation of microglia, and protected endotheliocytes. The positive influence of preconditioning factors on the morphometric parameters of the brain under ischemic conditions agrees with the results of behavioral tests (open field and elevated plus maze) that demonstrated increased locomotor activity and exploratory behavior of animals.