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1.
Astrobiology ; 24(6): 604-612, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38717897

RESUMO

The work considers the modelling of nearby supernova (SN) effects on Earth's biosphere via cosmic rays (CRs) accelerated by shockwaves. The rise of the radiation background on Earth resulted from the external irradiation by CR high-energy particles and internal radiation in organisms by the decay of cosmogenic 14C is evaluated. We have taken into account that the CR flux near Earth goes up steeply when the shockwave crosses the Solar System, while in previous works the CR transport was considered as purely diffusive. Our simulations demonstrate a high rise of the external ionization of the environments at Earth's surface by atmospheric cascade particles that penetrate the first 70-100 m of water depth. Also, the cosmogenic 14C decay is able to irradiate the entire biosphere and deep ocean organisms. We analyzed the probable increase in mutation rate and estimated the distance between Earth and an SN, where the lethal effects of irradiation are possible. Our simulations demonstrate that for SN energy of around 1051 erg the lethal distance could be ∼18 pc.


Assuntos
Radiação Cósmica , Planeta Terra , Ondas de Choque de Alta Energia , Taxa de Mutação
2.
Probl Sotsialnoi Gig Zdravookhranenniiai Istor Med ; 31(Special Issue 2): 1171-1175, 2023 Oct.
Artigo em Russo | MEDLINE | ID: mdl-38069881

RESUMO

Screening or its synonym medical check-up is the result of a health indicator, representing results of a medical examination and an effective tool of disease prevention. The concept of the term screening in European countries implies active detection of a disease or a premorbidity in people who are considered or consider themselves healthy. Medical check-up is a set of measures that includes preventive medical examination and additional methods of examinations conducted in order to assess the state of health and carried out in relation to certain groups of the population. The study and analysis of the international screening model and experience of its implementation, its role in the system of primary health care, including rehabilitation, is very important in terms of shaping public health at the international level. The article discusses regional trends in screening (medical check-up) and issues related to the conceptual and methodological aspects of medical check-up organization in the context of public health and prevention of risk factors. The data were searched in Scopus Web of Science, MedLine, the Cochrane Library, PubMed.


Assuntos
Saúde Pública , Humanos , Fatores de Risco , Federação Russa , Europa (Continente)/epidemiologia
3.
Urologiia ; (6): 117-121, 2023 Dec.
Artigo em Russo | MEDLINE | ID: mdl-38156694

RESUMO

Despite highly effective radical methods of treatment of prostate cancer (PC), 30% of patients will have a biochemical recurrence. The evolution in the diagnosis of recurrent prostate cancer after prostatectomy (RP) contributes to the search and development of such methods of treatment of relapses that consider not only the effectiveness, but also the quality of life of patients. This review demonstrates the actual concept of treatment of recurrent PC after RP, starting with salvage androgen-deprivation therapy with or without EBRT, and ending with minimally invasive methods such as salvage high-dose brachytherapy.


Assuntos
Braquiterapia , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/cirurgia , Antígeno Prostático Específico , Terapia de Salvação , Antagonistas de Androgênios , Qualidade de Vida , Recidiva Local de Neoplasia/cirurgia , Prostatectomia/efeitos adversos , Recidiva
4.
Artigo em Russo | MEDLINE | ID: mdl-37315243

RESUMO

The article is devoted to an urgent problem - primary and secondary prevention of atherosclerotic cardiovascular diseases. Modern approaches to management tactics depending on age and the appointment of antiplatelet therapy with acetylsalicylic acid in low doses from 75 to 150 mg/day are presented. At the same time, the relatively high effectiveness of the use of ASA for primary prevention in men 40-69 years old without an increased risk of bleeding from the gastrointestinal tract is shown. Low doses of ASA provide little benefit in reducing the risk of CVD in people 40 years and older, when there is no history of CVD, but at the same time they are at increased risk of CVD.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Prevenção Secundária , Aspirina/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Aterosclerose/prevenção & controle , Trato Gastrointestinal
5.
Ter Arkh ; 94(12): 1413-1420, 2023 Jan 16.
Artigo em Russo | MEDLINE | ID: mdl-37167187

RESUMO

BACKGROUND: The article reflects the clinical significance of the early diagnosis of toxic hepatitis in patients who have undergone a new coronavirus infection with the determination of clinical and laboratory predictors of the response to therapy. A dynamic analysis of the effectiveness of toxic hepatitis therapy in patients of three experimental groups and a control group is presented. AIM: The aim of the present study is to increase the effectiveness of the treatment of toxic hepatitis in patients who have undergone COVID-19. MATERIALS AND METHODS: On the basis of the newly created infection centers of the Central Clinical Hospital "RZhD-Medicine" and Vishnevsky 3-rd Central Military Clinical Hospital 996 patients with COVID-19, who had clinical and laboratory signs of toxic liver damage (cytolytic and/or cholestatic syndromes) against the background of COVID-19 therapy. RESULTS: On the 14th day from the start of therapy in group 3, there was a significant decrease in the clinical manifestations of jaundice in 163 (72.8%) patients, on the 21st day of treatment, this symptom was stopped in all patients. In groups 1 and 2, the decrease in clinical manifestations of jaundice was significantly lower - 122 (55.2%) and 134 (58.8%); p<0.05. At the end of therapy, no manifestations of jaundice were observed in all experimental groups, while in the control group, symptom reduction was achieved only in 47 (14.5%) patients. CONCLUSION: The use of drugs with hepatoprotective effect in the form of monotherapy in groups 1 (UDCA) and 2 (ademethionine) showed a low therapeutic effect with positive dynamics of clinical and laboratory indicators of toxic hepatitis activity. The use of combined treatment in group 3 (UDCA and ademethionine) demonstrated the maximum therapeutic effect, pronounced positive dynamics in the form of normalization of clinical and laboratory indicators of toxic hepatitis activity.


Assuntos
COVID-19 , Doença Hepática Induzida por Substâncias e Drogas , Icterícia , Humanos , Quimioterapia Combinada , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Resultado do Tratamento
6.
Ter Arkh ; 95(12): 1119-1127, 2023 Dec 28.
Artigo em Russo | MEDLINE | ID: mdl-38785051

RESUMO

AIM: To analyze long-term consequences of the new coronavirus infection and rehabilitation prospective of microbiocenosis-oriented therapy in patients with functional bowel disorders. MATERIALS AND METHODS: The study enrolled 100 consecutive patients with various types of functional bowel disorders with recurrence of symptoms after the new coronavirus infection. The severity of abdominal pain was evaluated in points, and bowel movement disorders were assessed using the Bristol stool scale. A questionnaire was used as part of an in-depth clinical examination for COVID-19 survivors to identify the clinical symptoms typical for the post-COVID syndrome. The Hospital Anxiety and Depression Scale was used to identify and assess the severity of depression and anxiety, and the Asthenic State Scale was used to diagnose the asthenia. RESULTS: All patients in the study subjectively linked the recurrence of bowel disorders with the new coronavirus infection. The most common bowel disorder was irritable bowel syndrome with diarrhea. A distinctive feature of exacerbations of intestinal symptoms in the post-COVID period is their association with depression/anxiety and asthenic states. The addition of Zakofalk® metaprebiotic to the treatment regimen was associated with significant regression of abdominal pain and normalization of bowel movement, an improvement of asthenia, anxiety, and depression. CONCLUSION: The addition of Zakofalk® to treatment regimens for exacerbations of functional bowel disorders after the new coronavirus infection significantly improves the effectiveness of therapy.


Assuntos
COVID-19 , Humanos , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/terapia , COVID-19/psicologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , SARS-CoV-2 , Síndrome do Intestino Irritável/psicologia , Síndrome do Intestino Irritável/microbiologia , Síndrome do Intestino Irritável/terapia , Estudos Prospectivos , Ansiedade/etiologia , Depressão/etiologia , Depressão/terapia , Astenia/etiologia , Astenia/reabilitação , Dor Abdominal/etiologia , Dor Abdominal/terapia , Síndrome de COVID-19 Pós-Aguda
7.
Kardiologiia ; 61(11): 104-107, 2021 Nov 30.
Artigo em Russo | MEDLINE | ID: mdl-34882084

RESUMO

The conditions of the pandemic caused by the novel coronavirus infection (COVID-19) are associated with overloading intensive care units, conversion of hospitals, and changes in routing of patients with acute cardiovascular pathology. At the same time, medical practice is still challenged to provide medical care to patients with acute coronary syndrome (ACS). Patients with COVID-19 and acute myocardial infarction (AMI) are at a higher risk of death while the incidence of this combination of diseases will be growing. This article describes a case of diagnosis and treatment of COVID-19 in a 69-year-old patient who was urgently hospitalized with cardiogenic shock associated with ACS, electrocardiographic signs of complete left bundle branch block, and left ventricular ejection fraction of 19 %. Coronary angiography with stenting was successfully performed in the conditions of extracorporeal membrane oxygenation. The patient received long-term intensive therapy in the intensive care unit followed by symptomatic treatment in the cardiac surgery unit. The patient's condition gradually improved and he was discharged from the hospital on the 56th day. The strategy of intensive care and active follow-up helped saving life of the patient with COVID-19 and AMI.


Assuntos
COVID-19 , Infarto do Miocárdio , Idoso , Humanos , Masculino , Infarto do Miocárdio/complicações , SARS-CoV-2 , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Volume Sistólico , Função Ventricular Esquerda
8.
Georgian Med News ; (316-317): 173-178, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34511467

RESUMO

The advantage of polylactide-based implants is their rapid and complete biodegradation, followed by replacement of the defect with bone tissue. The disadvantage of materials with a high biodegradation rate is their low support ability. The admixture of ceramic materials increases the strength of the implants and reduces the rate of biodegradation. 3D printing technology allows you to reduce the negative factors of ceramic impurities through the manufacture of implants of various porosities. Target. Determine the ultimate strength of a composite material based on PLA and TCP, manufactured by 3D printing with different porosity options, depending on the duration of hydration. Were made 9 samples of material with a size of 10x10x10 mm with different porosity 40%, 30%, 20%. Samples of the material were hydrated in saline. Strength tests were carried out on days 2, 10, and 20 after hydration, 3 samples of material of each porosity. All samples were tested for compression. The carried out comparative analysis indicates that the tested samples are statistically significant (at the level of p <0.05) differ from each other depending on the value of porosity at all periods of hydration. Although the average values of the ultimate strength of samples of the same porosity tend to decrease depending on the period of their hydration, these changes do not acquire statistical significance even between the extreme periods of observation. This is confirmed by the values of the indicator of the statistical significance of the differences p equal to 0.07; 0.759 and 0.124 for specimens with porosity of 20%, 30% and 40%, respectively. The tensile strength of samples of material based on polylactide and tricalcium phosphate, made using 3D printing, directly depends on their porosity, the smaller the pore volume, the stronger the samples. The hydration of the samples in saline solution for 20 days does not entail statistically significant changes in their strength regardless of the pore volume, although the average values of the ultimate strength for all tested samples tend to decrease.


Assuntos
Poliésteres , Alicerces Teciduais , Fosfatos de Cálcio , Teste de Materiais , Porosidade , Impressão Tridimensional
9.
Chaos ; 31(4): 043110, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34251250

RESUMO

Multiresolution wavelet analysis (MWA) is a powerful data processing tool that provides a characterization of complex signals over multiple time scales. Typically, the standard deviations of wavelet coefficients are computed depending on the resolution level and such quantities are used as measures for diagnosing different types of system behavior. To enhance the capabilities of this tool, we propose a combination of MWA with detrended fluctuation analysis (DFA) of detail wavelet coefficients. We find that such an MWA&DFA approach is capable of revealing the correlation features of wavelet coefficients in independent ranges of scales, which provide more information about the complex organization of datasets compared to variances or similar statistical measures of the standard MWA. Using this approach, we consider changes in the dynamics of coupled chaotic systems caused by transitions between different types of complex oscillations. We also demonstrate the potential of the MWA&DFA method for characterizing different physiological conditions by analyzing the electrical brain activity in mice.


Assuntos
Dinâmica não Linear , Análise de Ondaletas , Animais , Camundongos
10.
Opt Lett ; 46(14): 3360-3363, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264213

RESUMO

In this Letter, optical-to-terahertz (THz) conversion of 800 nm femtosecond laser pulses in large-area bias-free InGaAs emitters based on photo-Dember (PD) and lateral photo-Dember (LPD) effects is experimentally investigated. We use metamorphic buffers to grow sub-micrometer thick InxGa1-xAs layers with indium mole fractions x=0.37, 0.53, and 0.70 on a GaAs substrate. A strong enhancement of THz output energy with an increase of indium content is observed. On the surface of the sample providing the strongest emission (x=0.7), we have fabricated a 1.5cm2 area of asymmetrically shaped metallic grating for LPD emission. This LPD emitter allows achieving high conversion efficiency of 0.24⋅10-3 and a broad generation bandwidth of up to 6 THz. We also demonstrate that there is no significant difference in the conversion efficiency when operating at 1 and 200 kHz repetition rates. Our results show that large-area LPD emitters give a convenient, competitive way to generate intense high-repetition-rate THz pulses.

11.
Scanning ; 2021: 7626725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33560277

RESUMO

[This corrects the article DOI: 10.1002/sca.4950190702.].

12.
Ter Arkh ; 93(8): 890-896, 2021 Aug 15.
Artigo em Russo | MEDLINE | ID: mdl-36286883

RESUMO

AIM: Analysis of the effectiveness of therapy for non-alcoholic fatty liver disease (NAFLD) with severe asthenic syndrome. MATERIALS AND METHODS: In the period from 2017 to 2019, on the basis of the gastroenterology center of the Vishnevsky 3-rd Central Military Clinical Hospital, 247 patients with NAFLD, including those at the stage of steatohepatitis, and severe asthenic syndrome were examined and treated. The main group included 124 patients, the control group 123 patients. All patients underwent complex laboratory and instrumental diagnostics and neuropsychological research using the subjective asthenia assessment scale (MFI-20). In both groups, domestic drugs were included in the therapy regimen: from the 1st to the 10th day, Heptrong solution 3 ml intramuscularly in the morning; from the 1st to the 60th day UDCA 250 mg orally, 3 capsules at bedtime, Omega-3 forte 1000 mg, 2 capsules in the morning with meals. In group I patients received additionally from the 1st to the 10th day intravenous drip Cytoflavin 10 ml + 0.9% NaCl solution 200 ml; pentoxifylline solution 5 ml + 0.9% NaCl solution 200 ml. Then, from the 11th to the 60th day, Cytoflavin inside, 2 tablets 2 times a day. Pentoxifylline inside 400 mg 1 tablet 3 times a day. All patients underwent neuropsychological examination using the subjective asthenia rating scale (MFI-20). RESULTS: The effectiveness of treatment in patients of both groups was assessed by clinical, laboratory data and neuropsychological studies. In the main group, a significant reduction in asthenic syndrome was achieved against the background of diagnosed NAFLD compared with the control group. CONCLUSION: The early inclusion of patients with NAFLD and severe asthenic syndrome in the treatment regimen, in addition to the basic therapy of Cytoflavin, achieved a significantly high therapeutic effect in the form of normalization of the main clinical, laboratory and instrumental parameters, as well as a significant reduction in the manifestations of asthenia.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Pentoxifilina , Humanos , Astenia/diagnóstico , Astenia/tratamento farmacológico , Astenia/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Síndrome , Pentoxifilina/uso terapêutico , Solução Salina/uso terapêutico
13.
Ter Arkh ; 93(8): 923-931, 2021 Aug 15.
Artigo em Russo | MEDLINE | ID: mdl-36286887

RESUMO

BACKGROUND: The novel coronavirus infection COVID-19 can be manifested by damage to the organs of the gastrointestinal tract (GIT). Damage to the gastrointestinal tract by the SARS-CoV-2 virus leads to a violation of the microbial-tissue complex of the mucous membrane of the digestive tract. A common gastroenterological manifestation of COVID-19 is diarrhea. AIM: Study of the clinical features of gastroenterological disorders and the possibility of optimizing the treatment of diarrheal syndrome in patients with COVID-19 with a mild form of viral infection. MATERIALS AND METHODS: The observation group consisted of 230 patients with mild COVID-19: K-group (n=115) with respiratory symptoms, I group (n=115) with gastrointestinal manifestations in combination and without signs of respiratory damage. In order to compare the effectiveness of treatment of diarrheal syndrome, patients of group I are randomized into 2 subgroups: Ia (n=58) prebiotic treatment (Zacofalk) and Ib (n=57) enterosorbents. RESULTS: The development of gastrointestinal symptoms with SARS-CoV-2 infection is significantly more often noted in comorbid patients (67%). Gastrointestinal symptoms were dominated by diarrhea (93.9%) and flatulence (76.5%), in 1/3 of patients they were the first manifestos of infection. It was established that in 98.4% of patients of group I (against 42.6% of the K-group) signs of infectious intoxication were detected. In patients with gastrointestinal lesions, an elongation of the febrile period by 91.5 days was noted, a later (6 days) verification of the viral etiology of the disease. It was found that in patients of group I, the regression of clinical symptoms, the duration of viral disease, the dynamics of antibody formation, the prognosis for the development of IBS-like disorders in the post-infectious period depended on the treatment. In patients taking (Zacofalk), these indicators were significantly better. CONCLUSION: In mild cases, to reduce the severity of viral intestinal damage, for effective relief of intestinal symptoms, to reduce the risk of IBS-like symptoms, it is advisable to prescribe (Zacofalk) in an initial dose of 3 tablets per day.


Assuntos
COVID-19 , Gastroenteropatias , Humanos , Antidiarreicos , COVID-19/complicações , Diarreia/tratamento farmacológico , Diarreia/epidemiologia , Diarreia/etiologia , SARS-CoV-2
14.
Khirurgiia (Mosk) ; (11): 134-136, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33210519

RESUMO

Endometriosis is a functioning endometrial tissue outside the inner layer of the uterine wall. Liver endometriosis is one of the rarest forms of atypical endometriosis. In this article, we report a patient with this disease. A 59-year-old patient complained of heaviness and periodic pain in the right hypochondrium for more than a year. Previous contrast-enhanced CT revealed signs of cystic-solid hypovascular mass lesion in the right liver lobe. Histological examination revealed no reliable signs of tumor growth. According to control CT after 8 months, no significant changes were observed. Surgical treatment was indicated and atypical liver resection was performed. Histological examination revealed cystic endometrioid lesion. Liver endometrioma is a rare disease with unclear pathogenesis. Diagnosis is difficult due to uncharacteristic clinical manifestations and no specific markers. Liver endometriosis should be considered in differential diagnosis of liver lesion. Surgical treatment is preferable due to the risk of malignant transformation.


Assuntos
Endometriose , Hepatopatias , Endometriose/diagnóstico por imagem , Endometriose/patologia , Endometriose/cirurgia , Feminino , Hepatectomia , Humanos , Hepatopatias/diagnóstico por imagem , Hepatopatias/patologia , Hepatopatias/cirurgia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
15.
Khirurgiia (Mosk) ; (7): 25-30, 2020.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-32736460

RESUMO

OBJECTIVE: To evaluate the effectiveness and safety of aortic valve replacement through upper partial J-shaped sternotomy compared to conventional sternotomy. MATERIAL AND METHODS: There were 240 procedures of isolated aortic valve replacement for the period 2012-2017. According to inclusion criteria, 112 patients were randomized into 2 groups: group I - median sternotomy, group II - upper partial J-shaped sternotomy. Mean age of patients was 56.1±14.3 and 53.1±14.9 years, respectively (p=0.284). Females prevailed in both groups (55.4% vs. 57.1%, p=0.848). Peak pressure gradient on the aortic valve was 106.2±23.9 and 102.8±25.3 mm Hg, respectively (p=0.484). RESULTS: In-hospital mortality was 1.8% (n=1) in group I (p=0.315). Incidence of postoperative complications (complete atrioventricular blockade, ventricular septal defect) was similar (p=1.0). Mean time cross clamping in I and II groups was 65.5±12.5 and 64.7±13.1 min (p=0.729). Mean follow-up period was 31.6 and 33.5 months, respectively. Kaplan-Meier survival rate was 92.6 and 93.0%, respectively (log-rank test=0,767). Freedom from thromboembolic events was 91.7 and 90% (log-rank test=0.213). CONCLUSION. U: Pper partial J-shaped sternotomy is safe and effective for aortic valve surgery and characterized by similar outcomes compared to conventional sternotomy.


Assuntos
Valva Aórtica/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Esternotomia/métodos , Adulto , Idoso , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Retrospectivos , Resultado do Tratamento
16.
Chaos ; 30(7): 073138, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32752608

RESUMO

Detrended fluctuation analysis (DFA) is widely used to characterize long-range power-law correlations in complex signals. However, it has restrictions when nonstationarity is not limited only to slow variations in the mean value. To improve the characterization of inhomogeneous datasets, we have proposed the extended DFA (EDFA), which is a modification of the conventional method that evaluates an additional scaling exponent to take into account the features of time-varying nonstationary behavior. Based on EDFA, here, we analyze rat electroencephalograms to identify specific changes in the slow-wave dynamics of brain electrical activity associated with two different conditions, such as the opening of the blood-brain barrier and sleep, which are both characterized by the activation of the brain drainage function. We show that these conditions cause a similar reduction in the scaling exponents of EDFA. Such a similarity may represent an informative marker of fluid homeostasis of the central nervous system.


Assuntos
Barreira Hematoencefálica , Eletroencefalografia , Animais , Ratos , Sono
17.
J Phys Chem Lett ; 11(12): 4859-4865, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32515198

RESUMO

Supercapacitors based on carbon nanomaterials are attracting much attention because of their high capacitance enabled by large specific surface area. The introduction of heteroatoms such as N or O enhances the specific capacitance of these materials. However, the mechanisms that lead to the increase in the specific capacitance are not yet well-studied. In this Letter, we demonstrate an effective method for modification of the surface of carbon nanowalls (CNWs) using DC plasma in atmospheres of O2, N2, and their mixture. Processing in the plasma leads to the incorporation of ∼4 atom % nitrogen and ∼10 atom % oxygen atoms. Electrochemical measurements reveal that CNWs functionalized with oxygen groups are characterized by higher capacitance. The specific capacitance for samples with oxygen reaches 8.9 F cm-3 at a scan rate of 20 mV s-1. In contrast, the nitrogen-doped samples demonstrate a specific capacitance of 4.4 F cm-3 at the same scan rate. The mechanism of heteroatom incorporation into the carbon lattice is explained using density functional theory calculations.

18.
Kardiologiia ; 60(2): 47-53, 2020 Mar 05.
Artigo em Russo | MEDLINE | ID: mdl-32345198

RESUMO

Objective The search for predictors of severe (>35 %) left atrial (LA) fibrosis in patients (pts) with nonvalvular atrial fibrillation (AF) directed for catheter ablation (CA).Materials and Methods 69 pts with nonvalvular AF (57 paroxismal and 12 persistent) aged from 32 to 69 years (mean age 57.1±8.4, 28 females) were included in the study, among them 59 pts (86 %) with arterial hypertension (AH), 24 (34.8 %) - with AH and CAD. Complete physical study, laboratory tests (including NT-proBNP level), comprehensive echocardiography were performed. As a surrogate substrate of LA fibrosis, the area of low-voltage (<0.5 mV) zones in LA was estimated in the process of voltage electroanatomic mapping, as the first stage of CA. The total square of LA fibrosis in absolute values (Sf, cm2) and in percent of total LA square (Sf%), as well as the degree of fibrosis: degree I - <5 %, II - 5-19 %, III - 20-35 %, IV - >35 % were calculated. Degree IV of fibrosis was considered as severe fibrosis.Results Extent of fibrosis didn't depend on sex, age, body weight, presence of diabetes, CHA2DS2VASc scores, duration of AF history. There was a tendency to smaller Sf in pts with spontaneous termination of AF compared to those who required cardioversion: 7.2 cm2 (4.4; 17.1) and 12.6 cm2 (4.2; 30.5), respectively (p=0.069). Although NT-proBNP level was normal in 62 % of pts (<125 pg / ml), it was higher in Sf% ≥20 % than in Sf% <5 %: 146.0 (48.0; 276.0) and 42.8 (24.2; 91.0) pg / ml, respectively (p=0.0216). The distribution of pts by left ventricular (LV) geometry types was as follows: normal geometry (t.1) - 34, concentric remodeling (t.2) - 16, concentric LV hypertrophy (t.3) - 8, eccentric LV hypertrophy (t.4) - 11. Compared to pts with t. 1 (reference level), pts with t.3 and t.4 had higher LA volume and LV myocardial mass index, and pts with t.4 had larger end-diastolic LV volume and lower LV ejection fraction. Pts with t.4 tended to have higher Sf% than t.1: 31.1 (10.2; 46.2) and 11.2 (5.1; 28.0), respectively (p=0.053). Using logistic regression 3 independent predictors of LA severe fibrosis were detected: type 4 geometry of LV - OR=8.893 (95 % CI 1.150; 68.78), NT-proBNP >128 pg / ml - OR=6.184 (1.01; 37.99), LA volume index >34 ml / m2 - OR=5.92 (1.05; 33.38). According to ROC analysis, the area of the curve AUC = 0.839 (p<0.001), model specificity - 85.1 %, sensitivity - 70.0 %, predictive accuracy - 82.5 %.Conclusion In pts with nonvalvular AF predictors of severe (>35 %) LA fibrosis were LV geometry type in the form of eccentric LV hypertrophy, LA volume index >34 ml / m2 and NT-proBNP >128 pg / ml.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ablação por Cateter , Adulto , Idoso , Feminino , Fibrose , Átrios do Coração , Humanos , Masculino , Pessoa de Meia-Idade
19.
J Phys Condens Matter ; 32(24): 245001, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32079003

RESUMO

The size, form and distribution function of catalyst particles define the quality of synthesized arrays of carbon nanotubes. In this work, we study the kinetics of catalyst particle formation from the thin nickel film (9 nm) deposited on the silicon substrate (SiO2/Si) with a buffer layer of niobium nitride at the temperature of 880 °C. In the experiment, we have obtained the time dependences of the average radius, average height and concentration of nickel particles. The experimental data are satisfactorily described by simulations based on the wetting transition theory. Comparison of the simulation results and experimental data allows us to estimate the effective interaction potential between the nickel film and buffer layer of niobium nitride. Besides, we have estimated the viscosity of the nickel confirming an undercooled liquid state of the nanosized nickel film at the temperature of 880 °C.

20.
Urologiia ; (5): 105-108, 2019 Dec.
Artigo em Russo | MEDLINE | ID: mdl-31808641

RESUMO

A description of specific features of CT-MRI in rare patient with perirenal non-Hodgkins lymphoma is presented in the article. CT scan was used to determine the accumulation of contrast medium and pathological vessels along the right kidneys border. Diffusion weighted MRI revealed the low values of the measured diffusion coefficient (MDC) and high accumulation index of the paramagnetic in the tumor tissue (0.59-0.62). The specific features of perirenal non-Hodgkins lymphoma on CT/MRI, an evaluation of the tumors volume and stage, and signs of malignancy are described.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Renais/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Humanos
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