СЛОВО ОБ УЧИТЕЛЕ. ПАМЯТИ ЗАМЕЧАТЕЛЬНОГО ПЕДАГОГА И УЧЕНОГО М.Р. САПИНА

M.R. Sapin (1925–2015) was a professor at I.M. Sechenov First Moscow State Medical University, honorary academician of Russian academy of medical sciences (1988), and an outstanding representative of the Moscow anatomical school of the middle of XX – early XXI century. From the very beginning of his medical training, Mikhail Romanovich got interested in anatomy, especially in angiology and lymphology, and later concentrated on its studying. The author of more than 30 text books and guidelines for schools, universities, and colleges, Mikhail Romanovich was the doctoral and thesis advisor of 51 Ph.D. and approximately 70 MD dissertations. M.R. Sapin made a significant contribution to the development of anatomical education providing the departments with a various range of dry and wet specimens. His stunning and effective work as a tutor was highly appreciated by his students and colleagues, Russian and foreign anatomists. M.R. Sapin was the leader of the Laboratory of Functional Anatomy since 1972, president of the International Association of Morphologists (1992–2006), chairman of the expert commission of Higher Attestation Commission (1959–1994), etc. A man of a great willpower, M.R. Sapin faced a lot of obstacles in his life and research work but overcame that all successfully. The article presents the most important facts of anatomist’s career and lifetime.Михаил Романович Сапин — профессор Первого Московского государственного медицинского университета им. И.М. Сеченова, почетный академик Российской академии медицинских наук с 1988 г., выдающийся представитель Московской анатомической школы середины ХХ – начала ХХI в. С самого начала обучения в медицинском институте Михаил Романович заинтересовался ангиологией и лимфологией, изучению которых посвятил свою работу. Профессор М.Р. Сапин — автор более 30 учебных пособий для школ, колледжей и университетов, под его началом выполнены более 50 докторских и более 70 кандидатских диссертаций. М.Р. Сапин внес огромный вклад в развитие анатомической школы, оснащая кафедры широким ассортиментом сухих и влажных анатомических препаратов. Его великолепный преподавательский талант всегда высоко ценился не только студентами, но и сотрудниками кафедры, анатомами России и зарубежья. Академик М.Р. Сапин как человек великой силы воли преодолевал все препятствия, встречающиеся ему на жизненном пути, сохраняя себя и двигаясь вперед. В данной статье рассмотрены наиболее важные вехи в жизни великого ученого и учителя

ПОЛУЧЕНИЕ БЕСКЛЕТОЧНОГО МАТРИКСА ХРЯЩА ТРАХЕИ ДЛЯ ТКАНЕИНЖЕНЕРНЫХ КОНСТРУКЦИЙ

Background: Tissue-engineered trachea transplantation remains the last chance for a variety of patients suffering from severe cicatricial tracheal stenosis. Despite the series of carried studies, the final solution hasn’t been found. Creating a functionally complete hyaline cartilage graft in vitro still presents a fundamental problem, and a number of researchers consider it as the key to a successful tracheal tissue-engineering.Aims: The study aimed to investigate the capability of detergent complex and DNAse I for human tracheal cartilage decellularization in short-time exposition for acellular scaffold obtaining.Materials and methods: Isolated from cadaveric trachea human native cartilage was used for decellularization by ensimatic-detergent complex including Triton X-100, DMSO, and DNAse I. The scaffold was characterised by histological examinations, analysis of the residual DNA content, and cell metabolic activity colorimetric test with culture in the scaffold fragments.Results: The obtained scaffolds presented highly porous structure mostly composed of collagen and glycosaminoglycans with an insignificant residual DNA level, absence of citotoxicity, and capability for cell proliferative activity stimulation.Conclusions: Thus, the study provides a new short-time technology for hyaline cartilage decellularization in order to achieve acellular scaffolds in step with the tissue engineering requirements.Обоснование. Трансплантация тканеинженерной трахеи остается единственной надеждой для множества пациентов, страдающих тяжелыми рубцовыми стенотическими поражениями трахеи. Несмотря на существенное число выполненных исследований, окончательного решения проблемы пока не найдено. Вопрос о возможности создания функционально полноценной гиалиновой хрящевой ткани в трансплантате in vitro остается открытым, и ряд исследователей видят в нем ключ к успешному решению современных задач тканевой инженерии трахеи.Цель исследования ― оценить способность комбинации детергентов и ДНКазы I к децеллюляризации хрящевой ткани трахеи человека при кратковременном воздействии для получения бесклеточного матрикса-носителя.Методы. В исследовании использовался нативный хрящ человека, выделяемый из трахеи трупного донора и децеллюляризируемый комплексом детергентов и энзимов, включающих Тритон X-100, DMSO и ДНКазу I. Свойства получаемого матрикса-носителя оценивались в ходе гистологических исследований, анализа содержания остаточной ДНК в препарате и колориметрического теста метаболической активности клеток при культивировании на фрагментах носителя.Результаты. Полученные матриксы-носители обладали пористой структурой, преимущественно представленной коллагеном и гликозаминогликанами, демонстрировали низкий уровень остаточной ДНК, лишены цитотоксичности и способны стимулировать пролиферативную клеточную активность.Заключение. Результаты данного исследования позволили предложить новый метод непродолжительной децеллюляризации гиалиновой хрящевой ткани с получением клеточных носителей, отвечающих основным требованиям тканевой инженерии

A Solvable Regime of Disorder and Interactions in Ballistic Nanostructures, Part I: Consequences for Coulomb Blockade

We provide a framework for analyzing the problem of interacting electrons in a ballistic quantum dot with chaotic boundary conditions within an energy $E_T$ (the Thouless energy) of the Fermi energy. Within this window we show that the interactions can be characterized by Landau Fermi liquid parameters. When $g$, the dimensionless conductance of the dot, is large, we find that the disordered interacting problem can be solved in a saddle-point approximation which becomes exact as $g\to\infty$ (as in a large-N theory). The infinite $g$ theory shows a transition to a strong-coupling phase characterized by the same order parameter as in the Pomeranchuk transition in clean systems (a spontaneous interaction-induced Fermi surface distortion), but smeared and pinned by disorder. At finite $g$, the two phases and critical point evolve into three regimes in the $u_m-1/g$ plane -- weak- and strong-coupling regimes separated by crossover lines from a quantum-critical regime controlled by the quantum critical point. In the strong-coupling and quantum-critical regions, the quasiparticle acquires a width of the same order as the level spacing $\Delta$ within a few $\Delta$'s of the Fermi energy due to coupling to collective excitations. In the strong coupling regime if $m$ is odd, the dot will (if isolated) cross over from the orthogonal to unitary ensemble for an exponentially small external flux, or will (if strongly coupled to leads) break time-reversal symmetry spontaneously.Comment: 33 pages, 14 figures. Very minor changes. We have clarified that we are treating charge-channel instabilities in spinful systems, leaving spin-channel instabilities for future work. No substantive results are change

Erratum: "A Gravitational-wave Measurement of the Hubble Constant Following the Second Observing Run of Advanced LIGO and Virgo" (2021, ApJ, 909, 218)

[no abstract available

GW190814: gravitational waves from the coalescence of a 23 solar mass black hole with a 2.6 solar mass compact object

We report the observation of a compact binary coalescence involving a 22.2–24.3 Me black hole and a compact object with a mass of 2.50–2.67 Me (all measurements quoted at the 90% credible level). The gravitational-wave signal, GW190814, was observed during LIGO’s and Virgo’s third observing run on 2019 August 14 at 21:10:39 UTC and has a signal-to-noise ratio of 25 in the three-detector network. The source was localized to 18.5 deg2 at a distance of - + 241 45 41 Mpc; no electromagnetic counterpart has been confirmed to date. The source has the most unequal mass ratio yet measured with gravitational waves, - + 0.112 0.009 0.008, and its secondary component is either the lightest black hole or the heaviest neutron star ever discovered in a double compact-object system. The dimensionless spin of the primary black hole is tightly constrained to �0.07. Tests of general relativity reveal no measurable deviations from the theory, and its prediction of higher-multipole emission is confirmed at high confidence. We estimate a merger rate density of 1–23 Gpc−3 yr−1 for the new class of binary coalescence sources that GW190814 represents. Astrophysical models predict that binaries with mass ratios similar to this event can form through several channels, but are unlikely to have formed in globular clusters. However, the combination of mass ratio, component masses, and the inferred merger rate for this event challenges all current models of the formation and mass distribution of compact-object binaries

Constraints on the cosmic expansion history from GWTC–3

We use 47 gravitational wave sources from the Third LIGO–Virgo–Kamioka Gravitational Wave Detector Gravitational Wave Transient Catalog (GWTC–3) to estimate the Hubble parameter H(z), including its current value, the Hubble constant H0. Each gravitational wave (GW) signal provides the luminosity distance to the source, and we estimate the corresponding redshift using two methods: the redshifted masses and a galaxy catalog. Using the binary black hole (BBH) redshifted masses, we simultaneously infer the source mass distribution and H(z). The source mass distribution displays a peak around 34 M⊙, followed by a drop-off. Assuming this mass scale does not evolve with the redshift results in a H(z) measurement, yielding ${H}_{0}={68}_{-8}^{+12}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ (68% credible interval) when combined with the H0 measurement from GW170817 and its electromagnetic counterpart. This represents an improvement of 17% with respect to the H0 estimate from GWTC–1. The second method associates each GW event with its probable host galaxy in the catalog GLADE+, statistically marginalizing over the redshifts of each event's potential hosts. Assuming a fixed BBH population, we estimate a value of ${H}_{0}={68}_{-6}^{+8}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ with the galaxy catalog method, an improvement of 42% with respect to our GWTC–1 result and 20% with respect to recent H0 studies using GWTC–2 events. However, we show that this result is strongly impacted by assumptions about the BBH source mass distribution; the only event which is not strongly impacted by such assumptions (and is thus informative about H0) is the well-localized event GW190814

Anatomical bases of brain revascularization: choosing an extra-intracranial bypass option

Surgical brain revascularization is an important treatment for acute or chronic ischemia, intracranial aneurysms and skull base tu-mors. Individual anatomy of brain vessels should be clearly understood for this procedure. Variants of collateral cerebral blood flow in patients with cerebrovascular diseases depend on individual characteristics of circle of Willis and reserve mechanisms of collateral circulation. These anatomical variations require careful preoperative planning to choose the optimal revascularization option. © 2021, Media Sphera Publishing Group. All rights reserved

COVID-19. Liver damage - visualization features and possible causes

Item. To evaluate the features of CT imaging of the liver and the possible causes of pathological changes in COVID-19. Materials and methods. An analysis of the literature and our own data on the features of CT imaging of the liver in combination with biochemical analyzes in patients with COVID-19 was performed. The main possible causes of changes in the liver, as well as symptoms with CT, are examined. Results. The main target of the new SARS-CoV-2 coronavirus is the respiratory system. But among patients with COVID-19, along with damage to the central nervous system, myocardium, and intestines, cases of liver damage or dysfunction have been reported. This is expressed in an increase in biochemical markers of liver damage, as well as in a diffuse decrease in its density during CT, which is usually observed in the acute stage of the disease. © 2020 Medical Visualization. All rights reserved

Bioengineered Bile Duct: the project resume and state of the art in 2018

Aim. Development of the physiologically relevant tissue-engineered graft for repair of bile duct injures (Dyuzheva et al., 2016). <br><br>Conclusions. Designed scaffold showed no cytotoxicity, both BM-MSCs and cholangiocytes migrated into the depth of fibrous material. The constructs was biodegradable in various model mediums: deionized water, phosphate buffer, bile, full culture medium. The next step is pre-clinical trials on rabbits and minipigs for assessment of implantation safety and efficacy. We suppose that this tubular multilayered tissue-engineered construct will be capable to integration in native tissues after implantation and may be used to injured bile duct reparation