74 research outputs found

    The influence of modification by superdispersed powders on the lead-tin-base bronze structure

    Get PDF
    The paper presents data on the influence of additives of the pre-treated aluminium oxide powder on the structure of cast lead-tin-based bronzes. Different quantities of the modifier, based on the superdispersed aluminum oxide powder, were added to the bronze melt. The studies have shown that addition of a small amount of aluminum oxide powder (0.07... 0.25 %) allows modifying the micro structure of the obtained castings. This modification includes grain refinement, reduction of the matrix dendrites size of tin solid solution in copper, as well as formation of spherical inclusions of the low-melting phase - lead. In this case, the addition of such modifier influences weakly the morphology and the quantity of solid eutectoid inclusions based on electron compound Cu[31] Sn[8]

    Polytene chromosomes reflect functional organization of the Drosophila genome

    Get PDF
    Polytene chromosomes of Drosophila melanogaster are a convenient model for studying interphase chromosomes of eukaryotes. They are giant in size in comparison with diploid cell chromosomes and have a pattern of cross stripes resulting from the ordered chromatid arrangement. Each region of polytene chromosomes has a unique banding pattern. Using the model of four chromatin types that reveals domains of varying compaction degrees, we were able to correlate the physical and cytological maps of some polytene chromosome regions and to show the main properties of genetic and molecular organization of bands and interbands, that we describe in this review. On the molecular map of the genome, the interbands correspond to decompacted aquamarine chromatin and 5’ ends of ubiquitously active genes. Gray bands contain lazurite and malachite chromatin, intermediate in the level of compaction, and, mainly, coding parts of genes. Dense black transcriptionally inactive bands are enriched in ruby chromatin. Localization of several dozens of interbands on the genome molecular map allowed us to study in detail their architecture according to the data of whole genome projects. The distribution of proteins and regulatory elements of the genome in the promoter regions of genes localized in the interbands shows that these parts of interbands are probably responsible for the formation of open chromatin that is visualized in polytene chromosomes as interbands. Thus, the permanent genetic activity of interbands and gray bands and the inactivity of genes in black bands are the basis of the universal banding pattern in the chromosomes of all Drosophila tissues. The smallest fourth chromosome of Drosophila with an atypical protein composition of chromatin is a special case.  Using the model of four chromatin states and fluorescent in situ hybridization, its cytological map was refined and the genomic coordinates of all bands and interbands were determined. It was shown that, in spite of the peculiarities of this chromosome, its band organization in general corresponds to the rest of the genome. Extremely long genes of different Drosophila chromosomes do not fit the common scheme, since they can occupy a series of alternating bands and interbands (up to nine chromosomal structures) formed by parts of these genes

    РЕЗУЛЬТАТЫ ПРИМЕНЕНИЯ СЕЛЕКТИВНОЙ АДСОРБЦИИ ЭНДОТОКСИНА ПРИ СЕПСИСЕ У ОНКОЛОГИЧЕСКИХ БОЛЬНЫХ

    Get PDF
    Objective: to study the clinical efficiency of using selective lipopolysaccharide (LPS) adsorption in postoperative gram negative sepsis in cancer patients.Subjects and methods. Examinations were made in 47 patients (11 women and 36 men) aged 47 to 84 years, who had been operated on for cancer and whose postoperative period had been complicated by gramnegative sepsis. The patients were divided into 2 groups: 1) 15 patents who received standard therapy (a control group); 2) 32 who had LPS adsorption using immobilized polymyxin B (a study group).Results. Upon completion of the selective LPS adsorption program, there was regression of the clinical signs of sepsis, statistically significantly lower peripheral blood leukocyte and neutrophil levels, and better blood biochemical parameters in 87.5% of cases. High baseline endotox in activity decreased from >0.6 to <0.4 units in 89% of the patients. After the final session of LPS adsorption, the need for vasopressor support reduced due to hemodynamic profile optimization. After selective endotoxin adsorption cycles, 15 of 26 cases did not need to continue organ replacement therapy. Twentyeightday mortality rates in the study and control groups were 25.0 and 53.3%, respectively.Conclusion. Incorporation of LPS adsorption into a set of intensive therapy for gramnegative sepsis is pathogenetically substantiated and can effectively abolish the manifestations of the systemic effects of bacterial endotoxin. The early and timely use of LPS adsorption provides inhibition of an initiating stimulus, which makes it possible to prevent the progression of a septic process and the development of severe sepsis and septic shock and improves the results of therapy in cancer inpatients.Цель. Изучить клиническую эффективность применения селективной ЛПСадсорбции при грамотрицательном сепсисе, развившимся в послеоперационном периоде у онкологических больных.Материал и методы. Обследовано 47 больных в возрасте от 47 до 84 лет (11 женщин и 36 мужчин), подвергнутых хирургическому вмешательству по поводу онкологических заболеваний, послеоперационный период которых осложнился развитием грамотрицательного сепсиса. Больные были разделены на 2 группы — контрольную и основную. Контрольная группа — 15 человек, получавших стандартную терапию, основная группа — 32, которым была применена ЛПСадсорбция с иммобили зированным полимиксином В. Результаты. После завершения программы селективной ЛПСадсорбции в 87,5% случаев наблюдали регресс клинических признаков сепсиса, статистически значимое снижение уровня лейкоцитов и нейтрофилов в периферической крови, улучшение биохимических показателей крови. У 89% больных регистрировали снижение исходно высоких показателей активности эндотоксина от >0,6 ед. до <0,4 ед. После заключительного сеанса ЛПСадсорбции отмечено снижение потребности в вазопрессорной поддержке в связи с оптимизацией «гемодинамического профиля». В 15 из 26 случаев после проведения курсов селективной адсорбции эндотоксина необходимости в продолжении органозаместительной терапии не было. Летальность (28дневная) в основной группе составила 25,0%, в контрольной — 53,3%.Заключение. Включение в комплекс интенсивной терапии грамотрицательного сепсиса метода ЛПСадсорбции является патогенетически обоснованным и позволяет эффективно купировать проявления системного воздействия бактериального эндотоксина. Раннее и своевременное применение метода ЛПСадсорбции обеспечивает ингибирование инициирующего стимула, что позволяет предупредить прогрессирование септического процесса, развитие тяжелого сепсиса и септического шока, улучшает результаты лечения госпитального периода онкологических больных

    Спектрометрия ионной подвижности N-метилимидазола и возможности его определения

    Get PDF
    Objectives. To determine the ion mobility of N-methylimidazole, establish the structure of ions corresponding to characteristic signals, and determine the detection limit of N-methylimidazole on the ion-drift detector Kerber.Methods. Ion mobility spectrometry was used to study the ionization processes. The enthalpies of the reactions of monomer and dimer ions were calculated in the ORCA 4.1.1 software by the B3LYP density functional method with a set of basic functions 6-31G (d, p).Results. The drift time and ion mobility values of N-methylimidazole were determined. A method for mathematical processing of spectra and a program for its implementation was developed. The changing peculiarities of the ion mobility spectrum during measurement at a given time were studied. According to the interpretation of the spectrum signals, the structure of the generated ions was proposed, and the enthalpies of ion formation were determined.Conclusions. The characteristic signal of the N-methylimidazole ion protonated at the nitrogen atom of the pyridine type was revealed. It was found that two signals in the ion mobility spectra of N-methylimidazole correspond to the presence of the monomer and dimer ions. The detection limit of N-methylimidazole on the ion-drift detector Kerber was determined, amounting to 3 pg.Цели. Определение значений ионной подвижности N-метилимидазола. Установление строения ионов, соответствующих характерным сигналам. Определение предела обнаружения N-метилимидазола на ионно-дрейфовом детекторе Кербер.Методы. Метод спектрометрии ионной подвижности был использован для исследования процессов ионизации. Энтальпии реакций мономерных и димерных ионов расчитаны в программе ORCA 4.1.1 методом функционала плотности B3LYP с набором базисных функций 6-31G(d,p).Результаты. Определены значения времени дрейфа и ионной подвижности N-метилимидазола. Разработана методика математической обработки спектров и программа для ее реализации. Изучены особенности изменения характера спектра ионной подвижности в процессе измерения в данный момент времени. Предложено строение генерируемых ионов в соответствии с интерпретацией сигналов спектра. Определены энтальпии образования ионов.Выводы. Выявлен характеристический сигнал иона N-метилимидазола, протонированного по атому азота пиридинового типа. Установлено, что два сигнала в спектрах ионной подвижности N-метилимидазола соответствуют наличию мономерной и димерной формы ионов. Определен предел обнаружения N-метилимидазола на ионно-дрейфовом детекторе Кербер, составляющий 3 пг

    Measurement of neutrino and antineutrino neutral-current quasielasticlike interactions on oxygen by detecting nuclear deexcitation γ rays

    Get PDF
    Neutrino- and antineutrino-oxygen neutral-current quasielastic-like interactions are measured at Super-Kamiokande using nuclear de-excitation γ\gamma-rays to identify signal-like interactions in data from a $14.94 \ (16.35)\times 10^{20}protonsontargetexposureoftheT2Kneutrino(antineutrino)beam.Themeasuredfluxaveragedcrosssectionsonoxygennucleiare protons-on-target exposure of the T2K neutrino (antineutrino) beam. The measured flux-averaged cross sections on oxygen nuclei are \langle \sigma_{\nu {\rm -NCQE}} \rangle = 1.70 \pm 0.17 ({\rm stat.}) ^{+ {\rm 0.51}}_{- {\rm 0.38}} ({\rm syst.}) \times 10^{-38} \ {\rm cm^2/oxygen}withafluxaveragedenergyof0.82GeVand with a flux-averaged energy of 0.82 GeV and \langle \sigma_{\bar{\nu} {\rm -NCQE}} \rangle = 0.98 \pm 0.16 ({\rm stat.}) ^{+ {\rm 0.26}}_{- {\rm 0.19}} ({\rm syst.}) \times 10^{-38} \ {\rm cm^2/oxygen}$ with a flux-averaged energy of 0.68 GeV, for neutrinos and antineutrinos, respectively. These results are the most precise to date, and the antineutrino result is the first cross section measurement of this channel. They are compared with various theoretical predictions. The impact on evaluation of backgrounds to searches for supernova relic neutrinos at present and future water Cherenkov detectors is also discussed

    Search for electron antineutrino appearance in a long-baseline muon antineutrino beam

    Get PDF
    Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions

    Effect of SGLT2 inhibitors on stroke and atrial fibrillation in diabetic kidney disease: Results from the CREDENCE trial and meta-analysis

    Get PDF
    BACKGROUND AND PURPOSE: Chronic kidney disease with reduced estimated glomerular filtration rate or elevated albuminuria increases risk for ischemic and hemorrhagic stroke. This study assessed the effects of sodium glucose cotransporter 2 inhibitors (SGLT2i) on stroke and atrial fibrillation/flutter (AF/AFL) from CREDENCE (Canagliflozin and Renal Events in Diabetes With Established Nephropathy Clinical Evaluation) and a meta-Analysis of large cardiovascular outcome trials (CVOTs) of SGLT2i in type 2 diabetes mellitus. METHODS: CREDENCE randomized 4401 participants with type 2 diabetes mellitus and chronic kidney disease to canagliflozin or placebo. Post hoc, we estimated effects on fatal or nonfatal stroke, stroke subtypes, and intermediate markers of stroke risk including AF/AFL. Stroke and AF/AFL data from 3 other completed large CVOTs and CREDENCE were pooled using random-effects meta-Analysis. RESULTS: In CREDENCE, 142 participants experienced a stroke during follow-up (10.9/1000 patient-years with canagliflozin, 14.2/1000 patient-years with placebo; hazard ratio [HR], 0.77 [95% CI, 0.55-1.08]). Effects by stroke subtypes were: ischemic (HR, 0.88 [95% CI, 0.61-1.28]; n=111), hemorrhagic (HR, 0.50 [95% CI, 0.19-1.32]; n=18), and undetermined (HR, 0.54 [95% CI, 0.20-1.46]; n=17). There was no clear effect on AF/AFL (HR, 0.76 [95% CI, 0.53-1.10]; n=115). The overall effects in the 4 CVOTs combined were: Total stroke (HRpooled, 0.96 [95% CI, 0.82-1.12]), ischemic stroke (HRpooled, 1.01 [95% CI, 0.89-1.14]), hemorrhagic stroke (HRpooled, 0.50 [95% CI, 0.30-0.83]), undetermined stroke (HRpooled, 0.86 [95% CI, 0.49-1.51]), and AF/AFL (HRpooled, 0.81 [95% CI, 0.71-0.93]). There was evidence that SGLT2i effects on total stroke varied by baseline estimated glomerular filtration rate (P=0.01), with protection in the lowest estimated glomerular filtration rate (45 mL/min/1.73 m2]) subgroup (HRpooled, 0.50 [95% CI, 0.31-0.79]). CONCLUSIONS: Although we found no clear effect of SGLT2i on total stroke in CREDENCE or across trials combined, there was some evidence of benefit in preventing hemorrhagic stroke and AF/AFL, as well as total stroke for those with lowest estimated glomerular filtration rate. Future research should focus on confirming these data and exploring potential mechanisms

    Canagliflozin and Renal Outcomes in Type 2 Diabetes and Nephropathy

    Get PDF
    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to 300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m 2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

    Get PDF
    Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049
    corecore