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1.
Phys Rev Lett ; 132(23): 231903, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905689

RESUMEN

The cross section of the process e^{+}e^{-}→π^{+}π^{-} has been measured in the center-of-mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The measurement is based on an integrated luminosity of about 88 pb^{-1}, of which 62 pb^{-1} represent a complete dataset collected by CMD-3 at center-of-mass energies below 1 GeV. In the dominant region near the ρ resonance a systematic uncertainty of 0.7% was achieved. The implications of the presented results for the evaluation of the hadronic contribution to the anomalous magnetic moment of the muon are discussed.

2.
Probl Endokrinol (Mosk) ; 69(1): 86-95, 2023 02 25.
Artículo en Ruso | MEDLINE | ID: mdl-36842081

RESUMEN

The increasing of older age group in the population determines studying of age related diseases and emergence of new investigations in this area. In Female body, entering the menopausal transition is the start of «aging¼ of reproductive function and linked with decreasing of sex hormons levels. A direct connection between changes of estrogen, progesterone, androgen ratios and cognitive function of women was revealed. The anatomical localization of sex hormone receptors, the mechanisms of interaction of hormones with these receptors determine the ways of implementing biological effects of steroids on the CNS. Modern theories of «healthy nerve cells¼ and «eu-estrogenemia¼ explains the role of additional criteria, such as the absence of neurological diseases history and the duration of hypoestrogenia, to the outcome of menopausal hormone therapy. Additional factors that can affect to MHT action include: the composition of hormone therapy, administration methods, regimens (cyclic, continuous), duration of treatment, history of endocrine diseases, diabetes mellitus, gynecological history (parity, menarche age, COC use), heredity. The sections present the effect of menopausal transition on the development of depression, mood changes, sleep disturbances and mental disabilities. The explanation of negative effects of menopausal hormone therapy to cognitive health is also described by modern point of view. The ambivalent opinions of researchers, the potential of new reading of the results of earlier studies, confirms the necessity of continuing study of this topic.


Asunto(s)
Estrógenos , Menopausia , Embarazo , Femenino , Humanos , Anciano , Menopausia/fisiología , Menopausia/psicología , Estrógenos/uso terapéutico , Hormonas Esteroides Gonadales/fisiología , Terapia de Reemplazo de Hormonas/efectos adversos , Cognición
3.
Artículo en Ruso | MEDLINE | ID: mdl-36168699

RESUMEN

This paper reports two cases of Guillain-Barre syndrome associated with coronavirus infection COVID-19. The clinical symptoms and neurological status of patients, the data of the additional examination and the features of the prescribed therapy are described in detail. The issue of the tropicity of the SARS-CoV-2 virus to human nervous tissue and its possible ways of affecting the peripheral nervous system is discussed.


Asunto(s)
COVID-19 , Síndrome de Guillain-Barré , COVID-19/complicaciones , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/etiología , Humanos , SARS-CoV-2
4.
Artículo en Ruso | MEDLINE | ID: mdl-36036408

RESUMEN

OBJECTIVE: Obtaining additional data on the efficacy and safety of the drug Prospekta in the treatment of moderate cognitive impairment (MCI) and asthenia in patients with cerebrovascular disease (CVD). MATERIAL AND METHODS: A prospective observational study in more than 40 Russian cities enrolled 232 patients (mean age 61.5±10.0 years) with mild cognitive impairment (MCI), asthenia on ongoing basic nootropic therapy. The presence of MCI was confirmed by the Montreal Cognitive Assessment Scale (MoCA), asthenia - by 10-point Visual Analog Scale (VAS). All patients were prescribed the nootropic medication Prospekta 2 tablets 2 times a day for 8 weeks in addition to the therapy they received. Ultrasound Doppler sonography of the main arteries of the head and magnetic resonance imaging (MRI) of the brain were also assessed. At the end of treatment, the Clinical Global Impression Efficacy Index (CGI-EI) was assessed and the safety of the treatment was evaluated. RESULTS: The baseline severity of cognitive impairment according to the MoCA scale was 21.6 points, severity of asthenia according to the VAS was 6.3 points. According to Doppler flowmetry findings, hemodynamically significant stenosis was revealed in 105 (49.3%) patients, and narrowing of the main vessels without changes in hemodynamic parameters was revealed in 108 (50.7%) patients. According to MRI results, single vascular lesions in the brain matter were detected in 102 (44.0%) patients. The medications with nootropic effect were administered to 144 (62.1%) patients. A positive therapeutic response as improvement of cognitive functions was seen in 93.3% of patients after 8 weeks of taking Prospekta, including 39.4% of patients who had cognitive functions restored to the normal level. No side effects were registered during the observational study. CONCLUSIONS: The nootropic medication Prospekta is effective and safe in treatment of MCI in patients with asthenia with CVD, and improves cognitive function in patients with asthenia with CVD, both in monotherapy and in combination with other nootropic agents.


Asunto(s)
Enfermedades Cardiovasculares , Disfunción Cognitiva , Nootrópicos , Anciano , Astenia , Cognición , Humanos , Persona de Mediana Edad
5.
Artículo en Ruso | MEDLINE | ID: mdl-35758943

RESUMEN

Low back pain occupies one of the leading places among pain syndromes and is an urgent medical, social, and economic problem of our time. A review of modern domestic and foreign literature data on the features of diagnosis, treatment and rehabilitation of chronic dorsalgia in patients with comorbid pathology was carried out. The article reflects the main etiological factors, describes the types of back pain: non-specific (musculoskeletal), radiculopathy, pain associated with potentially dangerous diseases, in addition, issues of the pathogenesis of pain syndromes are highlighted with an indication of nociceptive, neuropathic, psychogenic components. The most common comorbidity in patients with chronic pain in the lower back is characterized. Diagnostic algorithms for the problem under study, measures of drug and non-drug therapy, the possibility of practicing yoga for chronic lower back pain from the standpoint of evidence-based medicine are considered. It was stated that the treatment of chronic pain in the lower back should be individual, with an impact on different links in the pathogenesis of the pathological process. At the same time, the practice of yoga allows you to comprehensively influence the body at various levels: physical, psychological, mental. However, further research is required in this area.


Asunto(s)
Dolor Crónico , Dolor de la Región Lumbar , Yoga , Dolor de Espalda , Dolor Crónico/terapia , Humanos , Dolor de la Región Lumbar/diagnóstico , Síndrome
6.
Zh Nevrol Psikhiatr Im S S Korsakova ; 122(3. Vyp. 2): 59-62, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-35318844

RESUMEN

OBJECTIVE: To evaluate the effect of Mexidol on the recovery of cognitive functions in patients after ischemic stroke (IS). MATERIAL AND METHODS: We examined 70 patients with acute IS, who were randomized into 2 groups by random sampling; The 1st group consisted of patients who, against the background of the main standard therapy for 14 days, received Mexidol intravenously, 500 mg 1 time per day, followed by oral administration of Mexidol FORTE 250, 750 mg per day for 60 days (40 patients; 28 men, 12 women). Group 2 consisted of 30 patients (21 men, 9 women) who received only standard therapy. RESULTS: Baseline scores on the MoCA and MMSE scales did not differ between the two groups. Retesting showed that the improvement on these scales was statistically more significant in the 1st group. The analysis of indicators of the evoked potential P300 confirmed a more pronounced positive trend in the 1st group (p<0.01). CONCLUSION: The use of sequential therapy with Mexidol is accompanied by a more complete recovery of cognitive functions in patients who have undergone IS.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular , Isquemia Encefálica/complicaciones , Femenino , Humanos , Masculino , Preparaciones Farmacéuticas , Picolinas/efectos adversos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/tratamiento farmacológico
7.
Opt Express ; 28(2): 1426-1438, 2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-32121854

RESUMEN

The interaction of non-monochromatic radiation with arrays comprising plasmonic and dielectric nanoparticles has been studied using the finite-difference time-domain electrodynamics method. It is shown that LiNbO3, TiO2, GaAs, Si, and Ge all-dielectric nanoparticle arrays can provide a complete selective reflection of an incident plane wave within a narrow spectral line of collective lattice resonance with a Q-factor of 103 or larger at various spectral ranges, while plasmonic refractory TiN and chemically stable Au nanoparticle arrays provide high-Q resonances with moderate reflectivity. Arrays with fixed dimensional parameters make it possible to fine-tune the position of a selected resonant spectral line by tilting the array relative to the direction of the incident radiation. These effects provide grounds for engineering novel selective tunable optical high-Q filters in a wide range of wavelengths, from visible to middle-IR.

8.
Opt Lett ; 44(23): 5743-5746, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31774768

RESUMEN

Collective lattice resonances (CLRs) in finite-sized $ 2D $2D arrays of dielectric nanospheres have been studied via the coupled dipole approximation. We show that even for sufficiently large arrays, up to $ 100 \times 100 $100×100 nanoparticles (NPs), electric or magnetic dipole CLRs may differ significantly from the ones calculated for infinite arrays with the same NP sizes and interparticle distances. The discrepancy is explained by the existence of a sufficiently strong cross-interaction between electric and magnetic dipoles induced at NPs in finite-sized lattices, which is ignored for infinite arrays. We support this claim numerically and propose an analytic model to estimate a spectral width of CLRs for finite-sized arrays. Given that most of the current theoretical and numerical researches on collective effects in arrays of dielectric NPs rely on modeling infinite structures, the reported findings may contribute to thoughtful and optimal design of inherently finite-sized photonic devices.

9.
Artículo en Ruso | MEDLINE | ID: mdl-30499494

RESUMEN

AIM: To evaluate the efficacy of cytoflavin inclusion in the complex therapy of patients with multiple sclerosis in the remitting form during the period of exacerbation. MATERIAL AND METHODS: The results of therapy of 41 patients matched for sex, age and parameters of clinical and laboratory data were analyzed. Depending on the scheme of therapy, patients were divided into 2 groups: patients of the first group (n=22) received hormonal therapy with methylprednisolone. Patients of group II (n=19) received cytoflavin. The efficacy of treatment was assessed by a set of clinical and laboratory indicators in dynamics - before the start of therapy, with a 10-day interval and after treatment. The neurological status was assessed with the most commonly used scales (functional system scale (FS), EDSS scale), also neuroimaging data were assessed. RESULTS AND CONCLUSION: The inclusion of cytoflavin as an antioxidant and neuroprotective agent in the therapy of patients with multiple sclerosis in the acute phase increased the efficacy of basic (hormonal) therapy, which is manifested in a significant decrease in the severity of neurologic symptoms and visual system disorders and fewer cases of non-response to treatment.


Asunto(s)
Mononucleótido de Flavina , Inosina Difosfato , Esclerosis Múltiple , Niacinamida , Succinatos , Combinación de Medicamentos , Mononucleótido de Flavina/uso terapéutico , Humanos , Inosina Difosfato/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Niacinamida/uso terapéutico , Succinatos/uso terapéutico , Resultado del Tratamiento
10.
Artículo en Ruso | MEDLINE | ID: mdl-30499503

RESUMEN

The presented article deals with traumatic brain injury, which can cause convulsive seizures with the subsequent development of epilepsy, which is especially characteristic of young people. The problems of classification of posttraumatic epileptic seizures, development of their mechanisms, characteristics of diagnosis, as well as the stages of epileptogenesis leading to the development of traumatic epilepsy are considered. The variants of therapy are given in view of traumatic brain injury. It is noted that the use of electrical stimulation during individual phases of paroxysmal oscillations can be an effective method in preventing the development of homeostatic plasticity that is involved in the development of epileptogenesis.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Epilepsia Postraumática , Epilepsia , Adolescente , Lesiones Traumáticas del Encéfalo/complicaciones , Epilepsia/etiología , Humanos , Convulsiones
11.
Dalton Trans ; 46(48): 16925-16938, 2017 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-29171856

RESUMEN

Herein, syntheses, crystal structures, and photoluminescence properties of 24 new ammonia and alkali metal ATCN salts characterized via single-crystal X-ray diffraction are reported. Moreover, ten structure types of these salts have been described, three of which are predominant. Some ATCNs were obtained as two crystalline polymorphs. It was estimated that most ATCN powders exhibited yellow-green fluorescence (at 450-600 nm). For samples that possess fluorescence of low intensity in the solid state, several optical centers of emission exist. It was speculated that the obtained spectral features were due to anion-anion intermolecular interactions. ATCN being a new representative of stable tetracyanoallyl salts is a promising candidate for creation of various 1D, 2D, and 3D supramolecular structures and potential functional materials.

12.
Vestn Rentgenol Radiol ; (1): 23-9, 2017.
Artículo en Ruso | MEDLINE | ID: mdl-30247858

RESUMEN

Objective: To compare a radiation dose obtained during standard digital radiography, tomosynthesis, and multislice spiral computed tomography (MSCT). Material and Methods: Life-size full body pediatric anthropomorphic mannequin phantom was examined with a Fujifilm FDR Ac Selerate 200 X-ray diagnostic apparatus and a Toshiba Aquilion Prime 64 computed scanner using the Piranha dosimetry equipment, as well as Gammex planar target, for comparison of the resolution of the apparatus. The effective radiation doses were calculated for different anatomical regions with the formulas specified in the methodical instructions, using the coefficients K and Kd. Results: The tables and graphs comparing the radiation dose when using different radiation diagnostic techniques were presented. The resolution of standard digital radiography versus that of tomosynthesis was analyzed. Fluctuations of the doses obtained were associated with the difference in the volume of irradiated tissue and in the presence of the doses in the irradiated volume of organs with high radiosensitivity. Optimal physical and technical parameters of photography were proposed, which could reduce a dose load on the patient, without significantly losing the quality of films. Conclusion: The effective doses of tomosynthesis were significantly higher than those of standard digital radiography (p < 0.05) while those of (MSCT) were above those of both X-ray and tomosynthesis, and the resolution of the latter was slightly lower.


Asunto(s)
Antropometría , Fantasmas de Imagen , Dosis de Radiación , Tomografía Computarizada Espiral , Tomografía por Rayos X , Antropometría/instrumentación , Antropometría/métodos , Niño , Humanos , Maniquíes , Salud Radiológica/métodos , Salud Radiológica/normas , Federación de Rusia , Tomografía Computarizada Espiral/métodos , Tomografía Computarizada Espiral/normas , Tomografía por Rayos X/métodos , Tomografía por Rayos X/normas
13.
Opt Express ; 24(23): 26851-26856, 2016 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-27857413

RESUMEN

Significant suppression of resonant properties of single gold nanoparticles at the surface plasmon frequency during heating and subsequent transition to the liquid state has been demonstrated experimentally and explained for the first time. The results for plasmonic absorption of the nanoparticles have been analyzed by means of Mie theory using experimental values of the optical constants for the liquid and solid metal. The good qualitative agreement between calculated and experimental spectra support the idea that the process of melting is accompanied by an abrupt increase of the relaxation constants, which depends, beside electron-phonon coupling, on electron scattering at a rising number of lattice defects in a particle upon growth of its temperature, and subsequent melting as a major cause for the observed plasmonic suppression. It is emphasized that observed effect is fully reversible and may underlie nonlinear optical responses of nanocolloids and composite materials containing plasmonic nanoparticles and their aggregates in conditions of local heating and in general, manifest itself in a wide range of plasmonics phenomena associated with strong heating of nanoparticles.

14.
Org Biomol Chem ; 14(15): 3758-64, 2016 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-27001914

RESUMEN

A novel fast, convenient and inexpensive synthesis of 1',3'-dioxo-1',3'-dihydrospiro[cyclopropane-1,2'-indene]-2,2,3,3-tetracarbonitrile and dimethyl 2,3-dicyano-1',3'-dioxo-1',3'-dihydrospiro[cyclopropane-1,2'-indene]-2,3-dicarboxylate is reported. These compounds undergo double carbanion cleavage under the action of alcohols resulting in the formation of stable salts, containing new allylic-type anions with potential application in organic electronics and as ionic liquid components.

15.
Ter Arkh ; 88(4): 105-111, 2016.
Artículo en Ruso | MEDLINE | ID: mdl-28635920

RESUMEN

Heart injury is one of the extrahepatic manifestations of chronic hepatitis C (CHC). The paper gives Russian and foreign authors' data on a relationship between CHC and myocardial injury. It discusses different pathogenetic components (the direct effect of the virus, immunological components), through which hepatitis C virus can induce myocarditis and cardiomyopathies in patients with CHC.


Asunto(s)
Hepatitis C Crónica/complicaciones , Miocarditis/complicaciones , Hepacivirus , Hepatitis C , Humanos , Federación de Rusia
16.
Stomatologiia (Mosk) ; 93(4): 27-9, 2014.
Artículo en Ruso | MEDLINE | ID: mdl-25377576

RESUMEN

The purpose of the study was to evaluate the structure of maxillofacial trauma associated with brain injury in Stavropol to elaborate the diagnostic approach. We analyzed 2,604 case records of patients with maxillofacial trauma in the Stavropol region in the period from 2008 to 2012. Only 345 (13.2%) cases were diagnosed with maxillofacial trauma associated with mild brain injury. The analysis of case records showed that the incidence of brain damage depends on the location and type of fracture of the facial bones. It is noted that emotional and stress factors often mask neurological symptoms that are important in the diagnosis of traumatic brain injury. To ensure the treatment success and reduce the duration of disability patients with maxillofacial trauma must be provided with special treatment with a more thorough analysis of possible neurological deficit followed by mandatory therapy for neurological symptoms.


Asunto(s)
Traumatismos Maxilofaciales/diagnóstico , Traumatismos Maxilofaciales/epidemiología , Adolescente , Adulto , Huesos Faciales/lesiones , Huesos Faciales/cirugía , Femenino , Hospitalización , Humanos , Masculino , Traumatismos Maxilofaciales/cirugía , Persona de Mediana Edad , Federación de Rusia/epidemiología , Cirugía Bucal/estadística & datos numéricos , Adulto Joven
17.
Persoonia ; 32: 115-26, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25264386

RESUMEN

During the last decade several new orders were established in the class Chytridiomycetes on the basis of zoospore ultrastructure and molecular phylogeny. Here we present the ultrastructure and molecular phylogeny of strain x-51 CALU - a parasite of the alga Tribonema gayanum, originally described as Rhizophydium sp. based on light microscopy. Detailed investigation revealed that the zoospore ultrastructure of this strain has unique characters not found in any order of Chytridiomycetes: posterior ribosomal core unbounded by the endoplasmic reticulum and detached from the nucleus or microbody-lipid complex, and kinetosome composed of microtubular doublets. An isolated phylogenetic position of x-51 is further confirmed by the analysis of 18S and 28S rRNA sequences, and motivates the description of a new genus and species Gromochytrium mamkaevae. The sister position of G. mamkaevae branch relative to Mesochytrium and a cluster of environmental sequences, as well as the ultrastructural differences between Gromochytrium and Mesochytrium zoospores prompted us to establish two new orders: Gromochytriales and Mesochytriales.

18.
Biofizika ; 59(2): 274-81, 2014.
Artículo en Ruso | MEDLINE | ID: mdl-25702479

RESUMEN

It is established that ion exchange resins AV-17-2P, KU-2, AV-16-GS, AM 21A, IMAC-HP, PUROLITE and fiber VION KN-1 can be applied as carriers for inulinase immobilization. The analysis of IR spectra for an enzyme, carriers and heterogeneous enzyme preparations showed that inulinase binding to matrices of various carriers occurs in general through electrostatic interactions. It is assumed that the mechanisms of interaction between inulinase from Kluyveromyces marxianus and the matrices of cation- and anion exchange polymers differ essentially from each other: different sites of protein molecule take part in adsorption that causes various conformational reorganizations in an enzyme molecule.


Asunto(s)
Proteínas Fúngicas/química , Glicósido Hidrolasas/química , Resinas de Intercambio Iónico/química , Kluyveromyces/enzimología , Absorción Fisicoquímica
19.
Vestn Khir Im I I Grek ; 172(4): 44-8, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24341244

RESUMEN

On the basis of examination of 35 dialytic patients, who had clinical findings of progressed chronic cardiac insufficiency against the background of the large arteriovenous shunt through existing vascular access, the authors show the complications. The volume of blood circulation along the arteriovenous fistula, which was more than 30% of cardiac output, caused dilatation of heart cavities with cardiac decompensation. If the largest potency to volume remodeling of native proximal arteriovenous fistulas is taken into account, this kind of access could cause hemodynamic abnormalities more often than others (in 22 (62.9%) of patients). The best primary survival was demonstrated by arteriovenous shunts (87.1%) during 2 years. However, long-term survival of native arteriovenous fistulas dramatically outperformed the other kinds of accesses. The choice of constant vascular access for hemodialysis is an important and difficult task in chronic renal disease of V degree patients.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Hemodinámica/fisiología , Fallo Renal Crónico/terapia , Diálisis Renal/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Fallo Renal Crónico/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
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