Influence of deformation on the structure and mechanical and corrosion properties of high-nitrogen austenitic 07Kh16AG13M3 steel

The correlation has been studied between the structure of a high-nitrogen austenitic Cr-Mn-N steel formed in the process of combined hardening treatment, including cold plastic deformation (CPD), and its mechanical and corrosion properties. The structure and properties of commercial high-nitrogen (0.8% N) 07Kh16AG13M3 steel is analyzed after rolling by CPD and aging at 500 and 800°C. It is shown that CPD of the steel occurs by dislocation slip and deformation twinning. Deformation twinning and also high resistance of austenite to martensitic transformations at true strains of 0.2 and 0.4 determine the high plasticity of the steel. The contribution of the structure imperfection parameters to the broadening of the austenite lines during CPD is estimated by X-ray diffraction. The main hardening factor is stated to be lattice microdistortions. Transmission electron microscopy study shows that heating of the deformed steel to 500°C leads to the formation of the intermediate CrN phase by a homogeneous mechanism, and the intermtallic χ phase forms along the austenite grain boundaries in the case of heating at 800°C. After hardening by all investigated technological schemes, exception for aging at 800°C, the steel does not undergo pitting corrosion and is slightly prone to a stress corrosion cracking during static bending tests, while aging at 800°C causes pitting corrosion at a pitting formation potential Epf = -0.25 V. © 2013 Pleiades Publishing, Ltd

Analysis of structural variations of the precipitate based on monitoring the industrial electrolysis of copper powders of various brands

This study is associated with the solution to the blending problem of the charge for the output of ready articles. The main requirements are claimed to the specific surface and the packed density of the powders of basic brands PML0, PMS-1, and GG. The dynamics of the development of the dendrite depositions for powders of mentioned brands with the simultaneous registration of the cathodic overvoltage is investigated under industrial experimental conditions. The procedure is developed and the results of the continuous monitoring of the deposition growth with the direct immersion of a video camera into the electrolyte are presented. The reproducibility of the results is evaluated statistically. Based on the galvanostatic crystallization model of the dendrite deposition on the rod electrode, the dynamics of varying the density (N) and radius (r t) of growing tips on the growth front is calculated. It is established by variance analysis that structural parameters N and r t are individual for depositions of every brand, so that the preparation conditions of the deposition during the electrolysis should be strictly fulfilled as the charge forms. © 2013 Allerton Press, Inc

Naturally occurring cobalamin (B12) analogs can function as cofactors for human methylmalonyl-CoA mutase

Cobalamin, commonly known as vitamin B12, is an essential micronutrient for humans because of its role as an enzyme cofactor. Cobalamin is one of over a dozen structurally related compounds - cobamides - that are found in certain foods and are produced by microorganisms in the human gut. Very little is known about how different cobamides affect B12-dependent metabolism in human cells. Here, we test in vitro how diverse cobamide cofactors affect the function of methylmalonyl-CoA mutase (MMUT), one of two cobalamin-dependent enzymes in humans. We find that, although cobalamin is the most effective cofactor for MMUT, multiple cobamides support MMUT function with differences in binding affinity (Kd), binding kinetics (kon), and concentration dependence during catalysis (KM, app). Additionally, we find that six disease-associated MMUT variants that cause cobalamin-responsive impairments in enzymatic activity also respond to other cobamides, with the extent of catalytic rescue dependent on the identity of the cobamide. Our studies challenge the exclusive focus on cobalamin in the context of human physiology, indicate that diverse cobamides can support the function of a human enzyme, and suggest future directions that will improve our understanding of the roles of different cobamides in human biology. Keywords: Cobalamin; Cobamide; MMUT; Methylmalonic aciduria; Methylmalonyl-CoA mutase; Vitamin B(12)

Современные представления о возможности применения антиангиогенных препаратов в качестве адъювантной терапии при неоваскулярной глаукоме

The article analyzes literature data on the use of modern antiangiogenic drugs in the treatment of neovascular glaucoma (NVG) presenting information on the mechanisms of action of inhibitors of vascular endothelial growth factor (VEGF) as adjuvant therapy in NVG, as well as the clinical effectiveness of these drugs in modulating the activity of ocular tissue healing processes after surgical treatment of glaucoma.The article also considers the results of studies on the use of VEGF inhibitors bevacizumab, ranibizumab, and aflibercept by different routes of administration. Usage of these drugs is indicated to require taking into account the contraindications, as well as the possibility of side effects associated with the intravitreal route of drug administration. The effects of anti-VEGF drugs in the treatment of NVG have been noted to be temporary and last 4–6 weeks, so the result of using a combination of these drugs and standard methods of treating the disease is assumed to be more pronounced and lasting.Выполнен анализ данных литературы о применении современных антиангиогенных лекарственных средств в лечении неоваскулярной глаукомы (НВГ). Приведены сведения о механизмах действия ингибиторов сосудистого фактора роста эндотелия сосудов (VEGF) в качестве адъювантной терапии при НВГ, а также клинической эффективности этих препаратов в отношении модулирования активности процессов заживления тканей глаза после хирургического лечения глаукомы.Рассмотрены результаты исследований применения ингибиторов VEGF: бевацизумаба, ранибизумаба и афлиберцепта при разных путях введения. Указано, что при использовании этих препаратов следует учитывать противопоказания к их применению, а также возможность возникновения побочных эффектов, связанных с интравитреальным путем введения. Отмечено, что эффекты анти-VEGF препаратов в лечении НВГ носят временный характер и длятся обычно 4–6 недель, в связи с этим предполагается, что более выраженным и длительным может быть результат использования комбинации этих лекарственных средств и стандартных методов лечения заболевания

Менингококковая инфекция у детей в период 2012–2021 гг. Основные итоги ретроспективного многоцентрового исследования, проблемы сегодняшнего дня

The heavy burden of meningococcal infection is associated not only with life-threatening complications in the acute period and high mortality in invasive forms of the disease, but also with severe consequences in survivors, who are not recorded in our country.The aim of study: to analyze clinical manifestations, complications of the acute period and outcomes of invasive forms of meningococcal disease in children in various regions of the Russian Federation.Materials and methods: an analysis of data from 1327 inpatient medical records of children with an invasive meningococcal infection from 14 regional centers of the Russian Federation for 2012-2021 was carried out (28.3% of cases of the disease in children in the represented federal districts).Results: it was found that young children predominated among the patients – the median was 27.4 (10.7-70.4) months. Complications of the acute period, often combined, were observed in 47.6% of cases. The development of septic shock was noted in 30.4%, Waterhouse-Friderichsen syndrome in 6.6%, carditis in 2.9%, cerebral edema in 15.7%, arthritis in 1.4% of cases; the formation of hydrocephalus, subdural effusion, sensorineural hearing loss in 1.8%, 0.6%, 1% of children, respectively. The presence of soft tissue necrosis requiring surgical intervention was noted in 3.5% of cases. Mortality rate was 10.1%. At the time of discharge from the hospital, 30% of children had complications associated with meningococcal infection: organ dysfunction/ failure in 13.2% of patients (severe in 1.3%), cerebral insufficiency in 19.6%; severe psycho-neurological deficits, sensorineural hearing loss, problems associated with the need for orthopedic/surgical interventions accounted for 0.7%, 0.6% and 0.8%, respectively.Conclusion. Considering the epidemiological features of meningococcal infection – the risk of a sharp increase in morbidity in short periods of time, the life-threatening nature of the disease itself, it is necessary to remain alert to these risks and take all possible measures to prevent the disease using all available means, the most effective of which is vaccine prevention.Тяжелое бремя менингококковой инфекции связано не только с жизнеугрожающими осложнениями острого периода и высокой летальностью при генерализованных формах заболевания, но и с тяжелыми последствиями у выживших, учет которых в нашей стране не ведется.Цель: проведение анализа клинических проявлений, осложнений острого периода и исходов генерализованных форм менингококковой инфекции у детей в различных регионах Российской Федерации.Материалы и методы: проведен анализ данных 1327 медицинских карт (форма 003/у) детей с генерализованной формой менингококковой инфекции из 14 региональных центров Российской Федерации за 2012– 2021 гг. (28,3% случаев заболевания у детей в представляемых федеральных округах).Результаты: установлено, что среди больных преобладали дети раннего возраста – медиана составила 27,4 (10,7–70,4) месяцев. Осложнения, часто сочетанные, в остром периоде заболевания наблюдались в 47,6% случаев: септический шок в 30,4%, синдром Уотерхауза – Фридериксена в 6,6%, кардит в 2,9%, отек головного мозга в 15,7%, артриты в 1,4%, гидроцефалия в 1,8%, сенсоневральная тугоухость в 1%, субдуральный выпот в 0,6% случаев. Наличие некрозов мягких тканей, требовавших хирургического вмешательства, отмечено в 3,5% случаев. Летальность составила 10,1%. На момент выписки из стационара у 30% детей выявлялись осложнения, в том числе выраженная органная дисфункция в 1,3%, грубый психоневрологический дефицит, сенсоневральная тугоухость; осложнения, требующие проведения ортопедических/хирургических вмешательств, составили 0,7%, 0,6% и 0,8% соответственно.Анализ полученных данных позволил вскрыть существующие проблемы, касающиеся клинической и этиологической диагностики заболевания, возможностей выявления осложнений острого периода и учета последствий генерализованных форм менингококковой инфекции.Заключение. Учитывая эпидемиологические особенности менингококковой инфекции (риск резкого подъема заболеваемости в короткие временные промежутки, жизнеугрожающий характер самого заболевания), необходимо сохранять настороженность в отношении данных рисков и предпринимать все возможные меры для профилактики заболевания с использованием всех доступных средств, наиболее эффективным из которых является вакцинопрофилактика

Sharing vitamins: Cobamides unveil microbial interactions

Microbial communities are essential to fundamental processes on Earth. Underlying the compositions and functions of these communities are nutritional interdependencies among individual species. One class of nutrients, cobamides (the family of enzyme cofactors that includes vitamin B12), is widely used for a variety of microbial metabolic functions, but these structurally diverse cofactors are synthesized by only a subset of bacteria and archaea. Advances at different scales of study-from individual isolates, to synthetic consortia, to complex communities-have led to an improved understanding of cobamide sharing. Here, we discuss how cobamides affect microbes at each of these three scales and how integrating different approaches leads to a more complete understanding of microbial interactions

Extra-osseous Ewing sarcoma of the pancreas: case report with radiologic, pathologic, and molecular correlation, and brief review of the literature

© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. In 2002, due to extensive histomorphologic, immunohistochemical, and cytogenetic similarities, the World Health Organization unified undifferentiated small round blue cell neoplasms of soft tissue and bone (previously segregated as Ewing sarcoma or Primitive Neuroectodermal tumor) into one category: Ewing family of tumors (EFT). Osseous EFT are more common, and while extra-osseous EFT can occur anywhere in the body, those of the pancreas are rare and likely to be seen in the second decade of life in the head of the pancreas. We report the case of a 39-year-old Caucasian male with a large heterogeneously enhancing mass in the pancreatic body. Pathologic examination showed a malignant round blue cell tumor diffusely positive for CD99, chromogranin, and synaptophysin; Ki-67 proliferation index was greater than 80%. FISH showed EWSR1 gene rearrangement in 90% of cells and Archer FusionPlexTM-targeted RNA sequencing analysis identified the EWSR1-FLI1 fusion transcript. The diagnosis of EFT of the pancreas was rendered. Unfortunately, the patient had minimal improvement and was transitioned to oral pain medications to continue care at a different institution