47 research outputs found

    Properties of the VT1-0 titanium surface modified by a pulsed ion beam

    Get PDF
    The physicomechanical properties of the VT1-0 titanium surface modified by a pulsed carbon ion beam at a pulse duration of 80 ns, an energy of 200 keV, a current density of 120 A/cm2, an energy density of 1.92 J/cm2, and various numbers of pulses (four regimes) are studied. Irradiation by the beam leads to hardening of a 1.8-μm-thick surface layer in titanium, a decrease in the hydrogen sorption rate, a decrease in the grain size, and the formation of twins

    Right heart condition in patients with COVID-19 pneumonia

    Get PDF
    Aim. To assess right heart condition in patients with coronavirus disease 2019 (COVID-19) pneumonia.Material and methods. One hundred and five patients with COVID-19 pneumonia were divided into 3 groups depending on the involvement of lung parenchyma: group I — 0-25%, II — 25-50%, III — 50-75%. The clinical status of patients was assessed using the NEWS2 and SHOKS-COVID scales. A complete blood count and biochemical blood tests were performed to determine the level of N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin I. Echocardiography was performed to assess the right heart structural, hemodynamic and functional parameters.Results. In patients with COVID-19 pneumonia, with an increase in lung parenchyma involvement, the intensity of systemic inflammatory response increased: C-reactive protein, group I — (4 [1,9; 35] mg/l), in III — (70,5 [33; 144] mg/l) (pI-III=0,012); myocardial stress marker level increased: NT-proBNP, group I — 77 [48; 150] ng/l, group III — 165 [100; 287] ng/l (pI-III=0,047). The dependence of NT-proBNP on C-reactive protein level was revealed (r=0,335, p=0,03). Intergroup comparison did not reveal significant differences between the main right heart functional parameters: TAPSE, Tei index (PW and TDI), FAC of the right ventricle (RV) (p>0,05). However, differences in the tricuspid annular peaks were found as follows: group I — 0,14 [0,12; 0,14] m/s, group II — 0,14 [0,12; 0,15] m/s, group III — 0,16 [0,14; 0,17] m/s (pI-II=0,012, pI-III=0,014) and RV global longitudinal strain: group I — 19,63±7,72%, group III — 27,4±5,93% (pI-III=0,014). The relationship between the RV global longitudinal strain and SHOKS-COVID score was confirmed (r=0,381; p=0,024).Conclusion. Patients with COVID-19 pneumonia showed no signs of right heart dysfunction. The development of RV hyperfunction was noted. Most likely, this is a compensatory mechanism in response to acute RV afterload. NT-proBNP increase under conditions of an inflammatory response may indicate myocardial stress. The results obtained allow to expand our understanding of the right heart condition in patients with COVID-19 pneumonia

    Germ Warfare in a Microbial Mat Community: CRISPRs Provide Insights into the Co-Evolution of Host and Viral Genomes

    Get PDF
    CRISPR arrays and associated cas genes are widespread in bacteria and archaea and confer acquired resistance to viruses. To examine viral immunity in the context of naturally evolving microbial populations we analyzed genomic data from two thermophilic Synechococcus isolates (Syn OS-A and Syn OS-B′) as well as a prokaryotic metagenome and viral metagenome derived from microbial mats in hotsprings at Yellowstone National Park. Two distinct CRISPR types, distinguished by the repeat sequence, are found in both the Syn OS-A and Syn OS-B′ genomes. The genome of Syn OS-A contains a third CRISPR type with a distinct repeat sequence, which is not found in Syn OS-B′, but appears to be shared with other microorganisms that inhabit the mat. The CRISPR repeats identified in the microbial metagenome are highly conserved, while the spacer sequences (hereafter referred to as “viritopes” to emphasize their critical role in viral immunity) were mostly unique and had no high identity matches when searched against GenBank. Searching the viritopes against the viral metagenome, however, yielded several matches with high similarity some of which were within a gene identified as a likely viral lysozyme/lysin protein. Analysis of viral metagenome sequences corresponding to this lysozyme/lysin protein revealed several mutations all of which translate into silent or conservative mutations which are unlikely to affect protein function, but may help the virus evade the host CRISPR resistance mechanism. These results demonstrate the varied challenges presented by a natural virus population, and support the notion that the CRISPR/viritope system must be able to adapt quickly to provide host immunity. The ability of metagenomics to track population-level variation in viritope sequences allows for a culture-independent method for evaluating the fast co-evolution of host and viral genomes and its consequence on the structuring of complex microbial communities

    Sarilumab in patients admitted to hospital with severe or critical COVID-19: a randomised, double-blind, placebo-controlled, phase 3 trial

    Get PDF
    Background: Elevated proinflammatory cytokines are associated with greater COVID-19 severity. We aimed to assess safety and efficacy of sarilumab, an interleukin-6 receptor inhibitor, in patients with severe (requiring supplemental oxygen by nasal cannula or face mask) or critical (requiring greater supplemental oxygen, mechanical ventilation, or extracorporeal support) COVID-19. Methods: We did a 60-day, randomised, double-blind, placebo-controlled, multinational phase 3 trial at 45 hospitals in Argentina, Brazil, Canada, Chile, France, Germany, Israel, Italy, Japan, Russia, and Spain. We included adults (≥18 years) admitted to hospital with laboratory-confirmed SARS-CoV-2 infection and pneumonia, who required oxygen supplementation or intensive care. Patients were randomly assigned (2:2:1 with permuted blocks of five) to receive intravenous sarilumab 400 mg, sarilumab 200 mg, or placebo. Patients, care providers, outcome assessors, and investigators remained masked to assigned intervention throughout the course of the study. The primary endpoint was time to clinical improvement of two or more points (seven point scale ranging from 1 [death] to 7 [discharged from hospital]) in the modified intention-to-treat population. The key secondary endpoint was proportion of patients alive at day 29. Safety outcomes included adverse events and laboratory assessments. This study is registered with ClinicalTrials.gov, NCT04327388; EudraCT, 2020-001162-12; and WHO, U1111-1249-6021. Findings: Between March 28 and July 3, 2020, of 431 patients who were screened, 420 patients were randomly assigned and 416 received placebo (n=84 [20%]), sarilumab 200 mg (n=159 [38%]), or sarilumab 400 mg (n=173 [42%]). At day 29, no significant differences were seen in median time to an improvement of two or more points between placebo (12·0 days [95% CI 9·0 to 15·0]) and sarilumab 200 mg (10·0 days [9·0 to 12·0]; hazard ratio [HR] 1·03 [95% CI 0·75 to 1·40]; log-rank p=0·96) or sarilumab 400 mg (10·0 days [9·0 to 13·0]; HR 1·14 [95% CI 0·84 to 1·54]; log-rank p=0·34), or in proportions of patients alive (77 [92%] of 84 patients in the placebo group; 143 [90%] of 159 patients in the sarilumab 200 mg group; difference −1·7 [−9·3 to 5·8]; p=0·63 vs placebo; and 159 [92%] of 173 patients in the sarilumab 400 mg group; difference 0·2 [−6·9 to 7·4]; p=0·85 vs placebo). At day 29, there were numerical, non-significant survival differences between sarilumab 400 mg (88%) and placebo (79%; difference +8·9% [95% CI −7·7 to 25·5]; p=0·25) for patients who had critical disease. No unexpected safety signals were seen. The rates of treatment-emergent adverse events were 65% (55 of 84) in the placebo group, 65% (103 of 159) in the sarilumab 200 mg group, and 70% (121 of 173) in the sarilumab 400 mg group, and of those leading to death 11% (nine of 84) were in the placebo group, 11% (17 of 159) were in the sarilumab 200 mg group, and 10% (18 of 173) were in the sarilumab 400 mg group. Interpretation: This trial did not show efficacy of sarilumab in patients admitted to hospital with COVID-19 and receiving supplemental oxygen. Adequately powered trials of targeted immunomodulatory therapies assessing survival as a primary endpoint are suggested in patients with critical COVID-19. Funding: Sanofi and Regeneron Pharmaceuticals

    Сравнительный анализ применения тоцилизумаба при тяжелых COVID-19-ассоциированных пневмониях у пациентов разных возрастных групп

    Get PDF
    According to accumulated clinical data, one of the causes of severe damage to lung epithelial cells associated with SARS-CoV-2 (2019-nCoV) is an acute, timely underestimated "cytokine storm" (cytokine cascade, hypercytokinaemia) with characteristic signs of an expressed hyper-inflammatory syndrome with subsequent polyorganic failure. The study presents the results of the analysis of the effectiveness of tocilizumab therapy (TCZ) in patients (n = 181) of different age groups with developed pneumonia caused by SARS-CoV-2. The aim of the study was to evaluate the effectiveness of TCZ therapy in patients of different age groups with developed pneumonia in the frame of COVID-19. Methods. Patients (n = 181) with community-acquired pneumonia caused by coronavirus SARS-CoV-2 are included in a one-center, non-randomized, prospective study to evaluate the effectiveness of TCZ therapy conducted at the State Public Health Institution "City Clinical Hospital No.52" of the Moscow City Health Department. Patients were divided into 3 age subgroups – up to 50 years, 50–70 years and over 70 years. Patients with community-acquired SARS-CoV-2-induced pneumonia receiving non-invasive oxygen support and patients who had artificial lung ventilation (ALV) were given a single dose of 400 mg of TCZ in addition to basic therapy. Results. There are no significant differences between age groups in the severity of pneumonia according to the data of the computed tomography (CT), however, a more severe condition and a higher mortality rate (p < 0.001) were reliably observed in patients over 70 age compared to the other age groups. After TCZ treatment in patients of each age group, the severity of the condition assessed on the National Early Warning Score (NEWS2) has been significantly reduced compared to the baseline. Conclusion. According to the data of the pilot study the efficacy and safety of TCZ in patients of all presented age groups with COVID-associated pulmonary tissue lesion and signs of "cytokine storm" was demonstrated. At the same time, patients up to 50 years after the therapy of TCZ managed to achieve greater clinical efficiency compared to patients in other groups. According to the severity of the state and laboratory criteria, the lowest clinical efficacy of TCZ therapy was observed in patients over 70 years of age; as a consequence, the highest mortality rate was observed in the same group. At the same time, the TCZ therapy has not had a positive impact on the change of laboratory values and the severity of the disease in case of unfavorable outcome. Согласно накопленным клиническим данным, одной из причин тяжелых повреждений клеток эпителия легких, ассоциированных с SARS-CoV-2 (2019-nCoV), является острый, вовремя недооцененный синдром «цитокинового шторма» (цитокиновый каскад, гиперцитокинемия) с характерными признаками выраженного гипервоспалительного синдрома с последующей полиорганной недоста - точностью. В работе представлены результаты анализа эффективности терапии тоцилизумабом (ТЦЗ) у пациентов (n = 181) разных возрастных групп с развившейся пневмонией в рамках COVID-19. Целью исследования явилась оценка эффективности терапии ТЦЗ у пациентов разных возрастных групп с развившейся пневмонией, вызванной SARS-CoV-2. Материалы и методы. В одноцентровом нерандомизированном проспективном исследовании оценки эффективности терапии ТЦЗ, проведенном на базе Государственного бюд жетного учреждения здравоохранения «Городская клиническая больница № 52» Департамента здравоохранения города Мос - квы, приняли участие пациенты (n = 181) с внебольничной пневмонией, вызванной коронавирусом SARS-CoV-2. Больные были распределены в 3 возрастные подгруппы: до 50 лет, 50–70 лет, старше 70 лет. Пациентам с внебольничной пневмонией, вызванной SARS-CoV-2, получающим неинвазивную кислородную поддержку, и больным, у которых проводилась искусственная вентиляция легких (ИВЛ), в до полнение к основной терапии назначен ТЦЗ однократно в дозе 400 мг. Результаты. Достоверных различий между возрастными группами по тяжести пневмонии по данным компьютерной томографии (КТ) не выявлено, однако отмечено достоверно более тяжелое состояние и более высокий уровень смертности (p < 0,001) у больных старше 70 лет по сравнению с остальными возрастными группами. После терапии ТЦЗ у больных каждой из возрастных групп тяжесть состояния, оцененная по шкале National Early Warning Score (NEWS2), достоверно снизилась по сравнению с исходными показателями. Заключение. По данным пилотного исследования продемонстрирована эффективность и безопасность применения ТЦЗ у пациентов всех представленных возрастных групп с COVID-ассоциированным повреждением легочной ткани и признаками «цитокинового шторма». При этом у пациентов до 50 лет после терапии ТЦЗ удалось добиться бόльшей клинической эффективности по сравнению с больными остальных групп. По степени тяжести состояния и лабораторным критериям самая низкая клиническая эффективность терапии ТЦЗ отмечена у пациентов старше 70 лет; как следствие, в этой же группе отмечен самый высокий уровень смертности. При этом в случае неблагоприятного исхода терапия ТЦЗ не оказывала положительного влияния на изменение лабораторных показателей и степень тяжести заболевания.

    BLOOD PRESSURE 24-HOUR MONITORING IN ASSESSMENT OF AORTIC STIFFNESS IN OLDER PATIENTS WITH ARTERIAL HYPERTENSION

    Get PDF
    Aim. The assessment of aortic stiffness by the data of 24-hour blood pressure monitoring in patients with arterial hypertension of older age. Material and methods. Totally 68 patients with AH studied of the age from 43 to 82 years old, of those 26 women and 26 healthy volunteers, comparable by the age, of those 14 women. Patients with AH and healthy persons were separated in to 3 subgroups by the age. Also those with AH were separated into 4subgroups by the level of salt consumption. To everyone investigated we performed 24-hour blood pressure monitoring with mean daily systolic aortic blood pressure, pulse wave velocity in aorta and augmentation index in aorta; studied the amount of salt consumed. Results. It was found that aortic stiffness is higher in AH than in healthy same-agers. We found that with the age there is an increase of aortic augmentation index in aorta. It was also found that an increase in salt consumption up to 299 mmol per day of sodium is followed by an decreased augmentation index in aorta. Consumption of more than 300 mmol per day of sodium is related to an increase of augmentation index in aorta.Conclusion. Aortic stiffness increases with the age, and with the influence of hemodynamic factors (BP); increased salt consumption leads to decrease of aortic augmentation index and has dose-related effect

    The questions of magnetism titanomagnetite ores Gusevogorskoye deposits (measuring on the samples)

    No full text
    Put in order the results of measurements of a number of magnetic parameters on samples of titanomagnetite ores Gusevogorskoye deposit by standard methods: magnetoacoustic emission, the Curie temperature, residual and induced magnetization. It is shown that ore magnetism is conditioned by one the magnetic phase, but with the changing content of trace elements. It was noted the presence of maghemite a second magnetic phase in areas with advanced oxidation processes only. Is also noted a wide range of changes by induced (0.37-321.8 A/m) and residual (0.19-7685 A/m) of the magnetizations. Obviously, this is due to both the change in the amount of mineralization and textural-structural features highlight it. These processes led to the formation of different domain structures and predetermine the magnitude and direction of residual magnetization. The residual magnetization of the sample, which is the sum thermoremanent, chemical, crystal, viscous and dynamic magnitizations, due to the possible prevalence of the dynamic magnitization is not always adequately reflect the NRM of titanomagnetite ores in-situ

    Properties of the VT1-0 titanium surface modified by a pulsed ion beam

    No full text
    The physicomechanical properties of the VT1-0 titanium surface modified by a pulsed carbon ion beam at a pulse duration of 80 ns, an energy of 200 keV, a current density of 120 A/cm2, an energy density of 1.92 J/cm2, and various numbers of pulses (four regimes) are studied. Irradiation by the beam leads to hardening of a 1.8-μm-thick surface layer in titanium, a decrease in the hydrogen sorption rate, a decrease in the grain size, and the formation of twins
    corecore