Factors influencing graphene growth on metal surfaces

Graphene forms from a relatively dense, tightly-bound C-adatom gas, when elemental C is deposited on or segregates to the Ru(0001) surface. Nonlinearity of the graphene growth rate with C adatom density suggests that growth proceeds by addition of C atom clusters to the graphene edge. The generality of this picture has now been studied by use of low-energy electron microscopy (LEEM) to observe graphene formation when Ru(0001) and Ir(111) surfaces are exposed to ethylene. The finding that graphene growth velocities and nucleation rates on Ru have precisely the same dependence on adatom concentration as for elemental C deposition implies that hydrocarbon decomposition only affects graphene growth through the rate of adatom formation; for ethylene, that rate decreases with increasing adatom concentration and graphene coverage. Initially, graphene growth on Ir(111) is like that on Ru: the growth velocity is the same nonlinear function of adatom concentration (albeit with much smaller equilibrium adatom concentrations, as we explain with DFT calculations of adatom formation energies). In the later stages of growth, graphene crystals that are rotated relative to the initial nuclei nucleate and grow. The rotated nuclei grow much faster. This difference suggests first, that the edge-orientation of the graphene sheets relative to the substrate plays an important role in the growth mechanism, and second, that attachment of the clusters to the graphene is the slowest step in cluster addition, rather than formation of clusters on the terraces

Cytokine profile in psoriatic arthritis: search for relationships with inflammation and blood rheological properties

Objective. To estimate the serum levels of interleukins (IL) 6 and 10, tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) in patients with psoriatic arthritis (PSA) and their relationship with the clinical and laboratory parameters of inflammation and with erythrocyte aggregation (EA). Material and methods. The authors measured the serum levels of C-reactive protein (CRP) by immunonephelometry (BN, ProSPEC, Siemens) and those of TNF-α, IL-6 and IL-10, and VEGF by X-MAP technology using a BioPlex-200 system (Panel Human 27-Plex Bio-Rad, USA) in 80 patients with PSA [45 women and 35 men; mean age 41.7±10.5 years, mean duration of PSA and psoriasis was 5.0 (2.0; 12,5) and 15 (4; 26) years, respectively; DAS 3.9 (3.09; 5.16)]. The blood samples from 16 healthy donors matched to the examinees for gender and age served as a control. The parameters of EA [Т1(с); Кt (arb. units); β (с-1), I2,5 (%)] were estimated, by recording the rate of back light scattering. The median (Me) and interquartile range [Q25; Q75], and mean and standard deviations (M±σ) were calculated; the indicators were compared by the Mann-Whitney test and Student's t test. Correlation analysis was made using the Spearman rank correlation coefficient (R); p < 0.05 was considered statistically significant. Results. There were significantly higher serum levels of IL-6 and IL-10, TNF-α, and VEGF in patients with PSA than in the controls, and impaired blood rheological properties. There were significant correlations of the level of most cytokines (IL-6 and IL-10, VEGF) with both the values of the clinical and laboratory activity of PSA (self-rated pain, the number of swollen and tender joints, a physician's assessment of disease activity, DAS, erythrocyte sedimentation rate, and fibrinogen) and most parameters of EA (Т1, Kt и I2.5). No significant relationships were found between VEGF and CRP. Conclusion. The enhanced clinical and laboratory activity of PSA is attended by the systemic activation of immunological mediators of inflammation and neoangiogenesis and by impaired blood rheological properties, which supports the interaction of these factors in the immunopathogenesis of the diseases

Estimation of ergonomic indicators of special purpose clothing for patients with thermal injuries

This article discusses the determination of the optimal design allowances for a full factorial experiment in the development of special-purpose clothing for patients with thermal injuries in a hospital. To assess the ergonomic performance of special-purpose clothing, was used of pressure exerted by clothing on the human body. Based on the results of the study, a mathematical model was developed based on a full factorial experiment. In accordance with the presented mathematical models, the minimum values of contact pressures are obtained for the following values of construction parameters: for a cut with a sewn-in sleeve Warmhole = 15 cm, Ifa = 5,0 cm, Ic = 9 cm, Hse = 10 cm; for a cut with a raglan sleeve Warmhole = 15 cm, Ifa = 6 cm, Ic = 10 cm; for a cut with a one-piece sleeve Warmhole = 16 cm, Ifa = 6 cm, Ic = 11 cm

The creation and characterization of the bread wheat line with a centric translocation T2DL.2RL

The development of bread wheat introgressions with alien genetic material from cultural and wild Triticeae species is an effective method for expanding the wheat gene pool necessary for breeding. To date, numerous collections of introgressions as substitutions and chromosome modifications have been obtained; however, the creation and study of wheat with new valuable traits still remain an important line of research. Rye Secale cereale L., whose chromosomes carry genes that control valuable economic and biological characteristics and properties, is widely used to produce new wheat forms. In this study, a wheat-rye translocation obtained by backcrossing the wheat-rye disomic-substitution line 2R(2D)1 with the variety Novosibirskaya 67 was characterized. The chromosomal composition of karyotypes was studied using fluorescent in situ hybridization and C-banding. Two centric translocations, derived from two long arms of chromosomes 2D and 2R, T2DL.2RL, were identified, the remaining 40 wheat chromosomes did not undergo modifications. Meiosis in the lines was stable. Chromosomes T2DL.2RL formed bivalents in all meiocytes, which confirmed their homology. The morphological characteristics of the spike in the T2DL.2RL line and Novosibirskaya 67 did not differ. A comparative analysis of productivity between the T2DL.2RL translocation line and the parental forms, Novosibirskaya 67 and the 2R(2D)1 line, was carried out. The T2DL.2RL line is inferior to Novosibirskaya 67 in all characters with different confidence levels. The productivity characters of the 2R(2D)1 line exceeded or did not differ from those of T2DL.2RL, however, the mass of 1000 grains was significantly lower. The results showed the effect of the T2DL.2RL translocation on the trait “plant height”. This character was significantly lower than that of Novosibirskaya 67 in two vegetation periods. Consequently, the T2DL.2RL translocation reduces plant height and productivity

THE STATE OF NUTRITIONAL STATUS AND ITS IMPACT ON THE LEVEL OF COMORBIDITY IN PATIENTS ON HEMODIALYSIS

The aim of the study was to investigate the nutritive status and identify risk factors for cardiovascular disease in patients on hemodialysis. Material and methods. 144 patients on program hemodialysis were examined. All patients underwent general clinical and laboratory examination, lipid profile was examined, body mass index was calculated, waist and hip circumference was measured, ratio of waist circumference to the circumference of hip was determined, abdominal integral multi-frequency bioimpedansometry and multispiral computed tomography were performed. Results. Gender features of distribution of abdominal adipose tissue and dyslipidemia in patients on program hemodialysis were revealed. Women have a predominant accumulation of visceral adipose tissue, while men are characterized by a proportional distribution of subcutaneous and visceral adipose tissue in the abdominal area. Women compared to men have higher rates of atherogenic lipoprotein fractions, which level is closely related to the volume of visceral adipose tissue. Among the comorbidities in the examined patients, diseases of the cardiovascular system predominate. The regression analysis revealed that the most significant risk factor for the development of coronary artery disease is an increase in lowdensity lipoproteins, for chronic heart failure – an increase in waist circumference. Conclusions. The data obtained indicate the need to monitor the nutritional status of patients on hemodialysis to identify and correct risk factors for cardiovascular disease

THE EFFECT OF AN ANTI-TUMOR NECROSIS FACTOR-? AGENT ON DISEASE ACTIVITY,BLOOD RHEOLOGICAL PROPERTIES, AND THE ARTERIAL WALL IN PSORIATIC ARTHRITIS

Vascular dysfunction and inflammation in psoriatic arthritis (PsA) share the same pathogenetic mechanism wherein the proinflammatory cytokine tumor necrosis factor- (TNF-) plays a key role. Treatment with anti-TNF- agents is effective in inhibiting inflammation in PsA; however, their effect on the wall of large arteries has not been studied. Objective. To evaluate the effect of Adalimumab (ADA) on the arterial wall and blood rheological properties in PsA. Subjects and methods. Eighteen patients with PsA [12 women and 6 men; mean age 43.1±10.2 years; disease activity scores (DAS), 4.78 (4.0; 5.45)] were subcutaneously injected ADA, 40 mg/every two weeks, for 12 weeks. The investigators assessed the vascular wall, by measuring the mean and maximum common carotid intima-media thickness (IMT) by ultrasound duplex scanning, and arterial rigidity (AR), by determining the refraction index (RI,%) and the rigidity index by digital volume photoplethysmography and Doppler study measuring the aortic pulse wave velocity (PWV) in the carotid-femoral segment (Micromedical, UK), before and after treatment. Erythrocyte aggregation (EA) parameters [Т1 (sec), Kt (c.u.); (sec-1), I2,5 (%)] were measured recording the rate of inverse light scattering and the levels of blood lipids [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG)], and atherogenicity coefficient (AC) by routine methods on an automated Express plus analyzer (Bayer, Germany) at baseline, 4, and 12 weeks. The median and the interquartile range [Me (Q25; Q75)] were calculated; the changes in the parameters were estimated by the Wilcoxon test (Wt) and the Friedman test (Ft) for dependent samples;

Algorithm for determining the authenticity of biomedical cell preparations containing mesenchymal stem cells

The use of mesenchymal stem cells (MSCs), which have a pronounced immunomodulatory activity, is a promising direction in the development of biomedical cell preparations (BMCPs). In oncohematology, the use of BMCPs containing MSCs is aimed at supporting hematopoiesis during cotransplantation with hematopoietic stem cells (HSCs) and suppressing immune conflicts during allogeneic unrelated transplantation and severe autoimmune processes. An obligatory stage of registration of BMCPs is confirmation of the identity of the MSC cell line (CL), which includes the establishment of morphological characteristics, evaluation of the expression of specific markers and proteins, and confirmation of the genetic stability of CL during cultivation. Determination of markers of genetic stability is possible using various methods, however, according to the recommendations of the American National Standardization Institute, the standard is the analysis of short tandem repeats (STR analysis). The purpose of the study is to develop an algorithm for determining the authenticity of BMCPs containing MSCs, including STR analysis. Material and methods. Identification of MSC cells in BMCP was performed according to the criteria of the International Society for Cell Therapy. Viable cells were counted in a Goryaev chamber. Immunophenotypic characteristics of MSCs were determined by flow cytometry. The level of production of specific proteins was assessed using enzyme immunoassay. Genetic stability markers were identified by STR analysis. Results and discussion. The methods were tested in triplicate for ten BMCP samples to confirm the reproducibility and reliability of the results. The developed algorithm for determining the authenticity of BMCP has a high accuracy, as it includes the STR analysis technique, which makes it possible to identify 19 polymorphic STR markers located on different alleles. Using the method will allow BMCP manufacturers to go through the procedure of state registration of drugs

Организация деятельности противотуберкулезных медицинских учреждений в условиях пандемии COVID-19

The article analyzes the organization of work of N.V. Postnikov Samara Regional Clinical TB Dispensary in 2020. The special procedure has been developed for COVID-19 tests in patients referred to TB department. All cases of the new coronavirus infection (COVID-19) in tuberculosis patients that occurred in the Samara region in 2020 (n = 31) were studied. Infection control activities are the following: separate filter boxes have been provided for personnel and patients in each department; two observational departments have been organized where patients are admitted depending on the type of medical care. The polymerase chain reaction has been used to examine patients for COVID-19 before admission to TB hospital for planned medical care, and express tests for immunoglobulins M and G have been used when patients were admitted in an emergency. Of the 30 cases of intravital detection of concurrent infections (tuberculosis + COVID-19), in 56.7% (17 people), COVID-19 was treated in the in-patient unit specializing in treatment of the new coronavirus infection, and in 43.3% (13 people), treatment was outpatient; lethality made 1/30 (3.33%).Проанализирована организация работы ГБУЗ «Самарский областной клинический противотуберкулезный диспансер им. Н. В. Постникова» в 2020 г. Разработан алгоритм обследования пациентов на COVID-19 при направлении в туберкулезное отделение. Изучены все случаи новой коронавирусной инфекции (COVID-19) у больных туберкулезом в Самарской области в 2020 г. (n = 31). Меры инфекционной безопасности: организованы раздельные фильтр-боксы для сотрудников и пациентов в каждом структурном подразделении; выделены два обсервационных отделения в зависимости от формы оказания медицинской помощи. Обследование пациентов на COVID-19 перед госпитализацией в туберкулезный стационар проводилось методом полимеразной цепной реакции при оказании медицинской помощи в плановой форме, экспресс-методом определения иммуноглобулинов M и G – при оказании помощи в неотложной/экстренной форме. Из 30 случаев прижизненного выявления сочетанной патологии (туберкулез + COVID-19) в 56,7% (17 человек) лечение COVID-19 осуществлялось в условиях стационара для оказания медицинской помощи пациентам с новой коронавирусной инфекцией, в 43,3% (13 человек) – амбулаторно, летальность составила 1/30 (3,33%)

ENVIRONMENTALLY SAFE CHELATING AS STIMULATORS OF PLANT GROWTH

We carried out development of biological products on the basis of ecologically safe complexones which proved as the effective stimulating preparations for agriculture. The offered compounds, having effectively executed transport function on delivery of biometals to a plant or an animal, on light or in the conditions of natural dumping quickly decay on the amino acids making them and don’t shift ecological equilibrium

BRCA1 mutations in women with familial or early-onset breast cancer and BRCA2 mutations in familial cancer in Estonia

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to identify BRCA1 and BRCA2 mutations in the Estonian population. We analyzed genetic data and questionnaire from 64 early-onset (< 45 y) breast cancer patients, 47 familial cases (patients with breast or ovarian cancer and a case of these cancers in the family), and 33 predictive cases (patients without breast or ovarian cancer, with a family history of such diseases) from Estonia for mutations in the BRCA1 gene. A sub-set of familial cases and predictive cases were also analyzed for mutations in the BRCA2 gene.</p> <p>Methods</p> <p>For mutation detection, we used the Polymerase Chain Reaction-Single Stranded Conformation Polymorphism Heteroduplex Analysis (PCR-SSCP-HD), followed by direct DNA sequencing.</p> <p>Results</p> <p>We identified three clinically important mutations in the BRCA1 gene, including seven occurrences of the c.5382insC mutation, three of c.4154delA, and one instance of c.3881_3882delGA. We also detected six polymorphisms: c.2430T>C, c.3232A>G, c.4158A>G, c.4427T>C, c.4956A>G, and c.5002T>C. Four sequence alterations were detected in introns: c.560+64delT, c.560+ [36-38delCTT, 52-63del12], c.666-58delT, and c.5396+60insGTATTCCACTCC. In the BRCA2 gene, two clinically important mutations were found: c.9610C>T and c.6631delTTAAATG. Additionally, two alterations (c.7049G>T and c.7069+80delTTAG) with unknown clinical significance were detected.</p> <p>Conclusions</p> <p>In our dataset, the overall frequency of clinically important BRCA1 mutations in early-onset patients, familial cases, and predictive testing was 7.6% (144 cases, 11 mutation carriers). Pathogenic mutations were identified in 4 of the 64 early-onset breast cancer cases (6.3%). In familial cases, clinically important mutations in the BRCA1 gene were found in 6 of the 47 individuals analyzed (12.8%). In predictive cases, 1 clinically important mutation was detected in 33 individuals studied (3%). The occurrence of clinically important mutations in BRCA2 in familial cases of breast cancer was 2 of the 16 individuals analyzed (12.5%).</p