Crystal structure, thermal and electrotransport properties of NdBa1–xSrxFeCo0.5Cu0.5O5+δ (0.02 ≤ x ≤ 0.20) solid solutions

Using solid-state reactions method, the solid solutions of layered oxygen-deficient perovskites NdBa1–xSrxFeCo0.5Cu0.5O5+δ (0.02 ≤ x ≤ 0.20) were prepared; their crystal structure, thermal stability, thermal expansion, electrical conductivity and thermopower were studied. It was found that NdBa1–xSrxFeCo0.5Cu0.5O5+δ phases crystallize in tetragonal syngony (space group P4/mmm) and are p-type semiconductors, whose conductivity character at high temperatures changed to the metallic one due to evolution from the samples of so-called weakly-bonded oxygen. Partial substitution of barium by strontium in NdBaFeCo0.5Cu0.5O5+δ leads to the small decreasing of unit cell parameters, thermal stability and thermopower of NdBa1–xSrxFeCo0.5Cu0.5O5+δ solid solutions, increasing of their electrical conductivity values and slightly affects their linear thermal expansion coefficient and activation energy of electrical transport values

Association of decreased glomerular filtration rate with renal hemodynamic disorders and inflammatory biomarkers in patients with medically-controlled hypertension of high cardiovascular risk

Aim. To assess markers of chronic kidney disease (CKD) in patients with medically-controlled hypertension (HTN) (<140/90 mm Hg), as well as to analyze potential association of decreased glomerular filtration rate (GFR) <60 ml/min/1,73 m2 with clinical data and therapy; to establish significant determinants of GFR decrease in this category of patients.Material and methods. The study included 70 patients with HTN and office blood pressure (BP) <140/90 mm Hg aged 64 (57; 68) years (men, 48,6%), of whom 40 patients were examined within the Russian multicenter CHRONOGRAPH program. Office BP was 130 (120; 140)/80 (72; 82) mm Hg. GFR and albuminuria were assessed. Twenty-four-hour BP monitoring and Doppler ultrasound of renal blood flow with estimation of resistance indices (RI) were performed. The content of highsensitivity C-reactive protein (hsCRP), interleukins (IL) 1β, 6, 10 and lipid transport function parameters was determined.Results. CKD markers were detected in 31,4% of patients (in 27,1% — a decrease in GFR <60 ml/min/1,73 m2; in 12,9% — pathological albuminuria). Patients with CKD markers were older, had higher office systolic BP and nocturnal pulse pressure, higher blood hsCRP and RI levels throughout the renal flow, and lower high-density lipoprotein cholesterol levels. In the presence of CKD markers, calcium channel blockers, aldosterone receptor antagonists and statins were used more often. The results of correlation analysis were used to determine the determinants of GFR decline. In the general group, GFR values had inverse correlations with age (Rs=-0,58, p<0,0001), segmental intrarenal artery RI (Rs= -0,4232, p=0,0005), blood hsCRP (Rs=-0,3998, p=0,0007), IL-1β (Rs=-0,3139, p=0,0086), office BP and some 24-hour BP parameters. In the presence of CKD markers, a direct association of GFR and IL-10 was determined (Rs=0,4293, p=0,046). In the absence of such markers, GFR had an inverse correlation with IL-1β content (Rs=-0,3110, p=0,0333). A multiple linear regression model included following independent determinants of GFR: age, blood hsCRP and RI in the segmental intrarenal arteries.Conclusion. Among patients with medically-controlled HTN of high cardiovascular risk, a high prevalence of CKD markers was revealed (31,4%). Compared with patients with preserved renal function, in the presence of CKD markers, there were higher levels of office systolic BP, nocturnal pulse pressure, blood hsCRP, and intrarenal artery RI. Associations were established between GFR and the levels of hsCRP, IL-1β and IL-10, which confirms the pathological role of inflammatory biomarkers in developing renal dysfunction in high-risk HTN. Age, elevated blood hsCRP levels, and intrarenal artery RI are independent determinants of decreased GFR in patients with medically-controlled HTN of high and very high cardiovascular risk. The data obtained shows the need for early prescription of combination antihypertensive therapy with nephro- and vasoprotective effects in this category of patients, as well as with an ability to depress the chronic subclinical inflammation

ЭВОЛЮЦИЯ БИОПРОТЕЗОВ КЛАПАНОВ СЕРДЦА: ДОСТИЖЕНИЯ И ПРОБЛЕМЫ ДВУХ ДЕСЯТИЛЕТИЙ

This study elucidates the main clinical results achieved with epoxy-treated (ethylene glycol diglycidyl ether) porcine valve bioprostheses. New technologies of biomaterial modifi cation and an innovative design of bioprosthetic valves are presented. The ways of further artifi cial valve development are discussed.  В настоящей работе освещены основные клинические результаты использования ксеноаортальных биопротезов клапанов сердца, консервированных эпоксидным соединением (диглицидиловым эфиром этиленгликоля). Дано теоретическое обоснование инновационных технологий модификации биоматериала и новых конструкций клапанных биопротезов. Дискутируются пути дальнейшего развития данного направления на ближайшие годы.

X-ray line formation in the spectrum of SS 433

The mechanisms for the formation of X-ray lines in the spectrum of SS 433 are investigated by taking into account the radiative transfer inside the jets. The results of Monte Carlo numerical simulations are presented. The effect of a decrease in line intensity due to scattering inside the jet turns out to be pronounced, but it does not exceed 60% in magnitude on the entire grid of parameters. The line broadening due to scattering, nutational motion, and the contribution of satellites can lead to overestimates of the jet opening angle $\Theta$ from the line widths in Chandra X-ray observations. The fine structure of the lines turns out to be very sensitive to the scattering effects. This makes its investigation by planned X-ray observatories equipped with high-resolution spectrometers (primarily Astro-H) a powerful tool for diagnosing the parameters of the jets in SS 433.Comment: 23 pages, 14 figures, to be published in Astronomy Letters, v. 38, n. 7, p. 443 (2012

Transcatheter surgery of residual right ventricular outflow tract stenosis

Over the past 40 years, various types of prostheses have been developed for right ventricular outflow tract reconstruction. However, conduit stenosis and insufficiency due to valve degeneration occur frequently, decreasing the lifetime of patients. Transcatheter stenting of conduits does not always give favorable results and can lead to severe pulmonary regurgitation. The novel method of percutaneous pulmonary valve implantation is a good alternative to the surgical intervention according to data on long-term survival and quality of life

Effect of dapagliflozin therapy on achieving cardiovascular mortality target indicators in patients with heart failure

Aim. To assess the effect of therapy with sodium glucose co-transporter type 2 inhibitor dapagliflozin in patients with heart failure with reduced ejection fraction (CHrEF) on the state cardiovascular mortality target indicators.Material and methods. All adult Russian patients with NYHA class II-IV HFrEF (left ventricular ejection fraction ≤40%) were considered as the target population. The characteristics of patients in the study corresponded to those in the Russian Hospital HF Registry (RUS-HFR). The study suggests that the use of dapagliflozin in addition to standard therapy will be expanded by 10% of the patient population annually in 2022-24. Cardiovascular mortality modeling was performed based on the extrapolation of DAPA-HF study result. The number of deaths that can be prevented was calculated when using dapagliflozin in addition to standard therapy. Further, the contribution of prevented deaths with dapagliflozin therapy to the achievement of federal and regional cardiovascular mortality target indicators (1, 2 and 3 years) was calculated.Results. The use of dapagliflozin in addition to standard therapy for patients with NYHA class II-IV CHrEF with the expansion of dapagliflozin therapy by 10% of the patient population annually will additionally prevent 1729 cardiovascular death in the first year. This will ensure the implementation of cardiovascular mortality target indicators in Russia in 2022 by 11,8%. In the second year, 3769 cardiovascular deaths will be prevented, which will ensure the implementation of target indicators in 2023 by 17,2%. In the third year, 5465 cardiovascular deaths prevented, which will ensure the implementation of implementation of target indicators in 2024 by 18,7%.Conclusion. The use of dapagliflozin in addition to standard therapy for patients with NYHA class II-IV CHrEF will ensure the implementation of implementation of target indicators in 2024 by 18,7%

Polarization of X-ray lines from galaxy clusters and elliptical galaxies - a way to measure tangential component of gas velocity

We study the impact of gas motions on the polarization of bright X-ray emission lines from the hot intercluster medium (ICM). The polarization naturally arises from resonant scattering of emission lines owing to a quadrupole component in the radiation field produced by a centrally peaked gas density distribution. If differential gas motions are present then a photon emitted in one region of the cluster will be scattered in another region only if their relative velocities are small enough and the Doppler shift of the photon energy does not exceed the line width. This affects both the degree and the direction of polarization. The changes in the polarization signal are in particular sensitive to the gas motions perpendicular to the line of sight. We calculate the expected degree of polarization for several patterns of gas motions, including a slow inflow expected in a simple cooling flow model and a fast outflow in an expanding spherical shock wave. In both cases, the effect of non-zero gas velocities is found to be minor. We also calculate the polarization signal for a set of clusters, taken from large-scale structure simulations and evaluate the impact of the gas bulk motions on the polarization signal. We argue that the expected degree of polarization is within reach of the next generation of space X-ray polarimeters.Comment: 25 pages, 18 figures, accepted to MNRA

Mycophenolate Mofetil and Clostridium difficile-associated Colitis

Aim. A clinical observation of colitis conditioned by mycophenolate mofetil intake and concomitant Clostridium difficile-associated disease.Key points. Mycophenolate mofetil (MMF) is an active immunosuppressant with side effects affecting gastrointestinal tract (GIT). A 37-yo male patient with type 1 diabetes mellitus was admitted at a gastroenterology unit with clinical signs of diarrhoea with haematochezia. A history of diabetic nephropathy and related-donor pre-dialysis kidney transplantation in 2012, since when MMF intake was 2000 mg daily. Catarrhal ulcerative colitis in colonoscopy, C. difficile toxins in pathogen stool panel. Ulcerative, ischaemic colitises and the graft-versus-host disease were ruled out in examination. A positive clinical and endoscopic trend was observed upon MMF withdrawn and start of vancomycin.Conclusion. The case presented illustrates the clinical picture and diagnostic algorithm in MMF-associated colitis. The case-distinctive is association with C. difficile infection

Retrospective Analysis of the Safety of Antibacterial Medicinal Products for Elderly Patients with Community-Acquired Lower Respiratory Tract Infections

Cephalosporins are the empirical antibiotic therapy (ABT) of choice for patients with community-acquired pneumonia (CAP). When treated with antibiotics, elderly patients, especially those with comorbidities, are at higher risk of developing adverse drug reactions (ADRs).The aim of the study was to analyse data on the safety and efficacy of initial empirical ABT with cephalosporins in elderly patients over 75 years old with CAP admitted to multidisciplinary hospitals in Moscow.Materials and methods. The retrospective study included 305 medical records of patients with CAP admitted to three multidisciplinary hospitals in Moscow in 2017–2019 and prescribed initial mono- and/or combination ABT including a cephalosporin. Initial ABT was considered effective if the body temperature normalised within 48–72 h from the start of treatment. It was considered safe if there were no ADRs during hospital stay.Results. Mostly, patients were prescribed ceftriaxone monotherapy or ceftriaxone and azithromycin combination therapy. These ABT regimens were effective in 69.07% and 78.10% of the cases, respectively. Patients with severe CAP needed their initial ABT adjusted significantly more often than those with non-severe CAP. The initial ABT was changed for a number of reasons, including ineffectiveness, ADRs, abscesses formed as a complication of CAP, sputum culture results enabling causal ABT, secondary hospital-acquired infections, and exacerbated chronic infections. All patients had comorbidities, and the most prevalent were arterial hypertension (83.9%), coronary heart disease (45.6%), chronic heart failure (44.9%), cerebrovascular disease (40.9%), atrial fibrillation (26.9%), diabetes mellitus (21.3%), and chronic obstructive pulmonary disease (19.0%). Initial ABT was significantly more often considered ineffective in patients with chronic heart failure and cerebrovascular disease. The most common causative agent of CAP in the study population was Streptococcus pneumoniae (31.9%). In 16% of patients, the authors identified ADRs associated with the antibiotics used as initial therapy. The most common were diarrhoea, anaemia, leucopenia, and hepatopathy. Ceftriaxone was associated with ADRs in 11% of patients.Conclusions. The study results suggest that initial mono- and/or combination ABT including a cephalosporin is effective and relatively safe; therefore, this treatment option is expedient for elderly patients with CAP. For this population, the safety of ABT may be improved through the wider use of existing markers of ADRs and the identification of new ones

Evaluation of the Efficacy and Safety of Initial Empirical Antibiotic Therapy for Community-Acquired Pneumonia in Middle-Aged People

β-lactam antibiotics, including cephalosporins, are the drugs of choice for empirical antibiotic therapy (ABT) in patients with community-acquired pneumonia. Unreasonable and irrational use of antibiotics leads to an increased risk of adverse reactions, contributes to the growth of antibiotic resistance.The aim of the study was to analyse data on the efficacy and safety of initial empirical ABT using cephalosporins for community-acquired pneumonia in middle-aged patients of multidisciplinary hospitals in Moscow.Materials and methods: the authors analysed 177 archived medical records of the patients admitted to three multidisciplinary hospitals (I.V. Davydovsky City Clinical Hospital, City Clinical Hospital 52 and City Clinical Hospital 4) in Moscow from 2017 to 2019 and prescribed mono- and/or combination therapy including a cephalosporin antibiotic as a starting therapy for community-acquired pneumonia. The initial ABT was considered effective if a patient’s body temperature normalised within 48–72 h following initiation of treatment and safe if no adverse reactions developed during the period of inpatient treatment.Results: the combination of ceftriaxone and azithromycin was the most frequently prescribed ABT regimen; its effectiveness was 71.9%. Ceftriaxone monotherapy was the second in frequency of prescription; its effectiveness amounted to 77.2%. The third regimen included cefotaxime and azithromycin and was effective in 70% of cases. The patients who needed a change in initial ABT had a significantly higher incidence of developing severe community-acquired pneumonia and complications. The study results indicate that the structure of comorbidity did not affect the effectiveness of initial empirical ABT. Streptococcus pneumoniae was found to be the most common causative agent of community-acquired pneumonia in the studied population (44.8% of cases). Only 13% of the patients faced adverse reactions associated with the use of antibiotics as part of the initial empirical ABT; the most common were leukopenia and diarrhoea.Сonclusions: the results of the study indicate the feasibility of mono- and/or combination ABT including a cephalosporin antibiotic as a starting empirical therapy for community-acquired pneumonia due to its effectiveness and favourable safety profile