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

Open data from the third observing run of LIGO, Virgo, KAGRA, and GEO

The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame mass M > 70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 < e ≤ 0.3 at 16.9 Gpc−3 yr−1 at the 90% confidence level

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

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

International audienceGravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

International audienceGravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Search for subsolar-mass black hole binaries in the second part of Advanced LIGO's and Advanced Virgo's third observing run

International audienceWe describe a search for gravitational waves from compact binaries with at least one component with mass 0.2 $M_\odot$--$1.0 M_\odot$ and mass ratio $q \geq 0.1$ in Advanced LIGO and Advanced Virgo data collected between 1 November 2019, 15:00 UTC and 27 March 2020, 17:00 UTC. No signals were detected. The most significant candidate has a false alarm rate of 0.2 $\mathrm{yr}^{-1}$. We estimate the sensitivity of our search over the entirety of Advanced LIGO's and Advanced Virgo's third observing run, and present the most stringent limits to date on the merger rate of binary black holes with at least one subsolar-mass component. We use the upper limits to constrain two fiducial scenarios that could produce subsolar-mass black holes: primordial black holes (PBH) and a model of dissipative dark matter. The PBH model uses recent prescriptions for the merger rate of PBH binaries that include a rate suppression factor to effectively account for PBH early binary disruptions. If the PBHs are monochromatically distributed, we can exclude a dark matter fraction in PBHs $f_\mathrm{PBH} \gtrsim 0.6$ (at 90% confidence) in the probed subsolar-mass range. However, if we allow for broad PBH mass distributions we are unable to rule out $f_\mathrm{PBH} = 1$. For the dissipative model, where the dark matter has chemistry that allows a small fraction to cool and collapse into black holes, we find an upper bound $f_{\mathrm{DBH}} < 10^{-5}$ on the fraction of atomic dark matter collapsed into black holes

Search for subsolar-mass black hole binaries in the second part of Advanced LIGO's and Advanced Virgo's third observing run

International audienceWe describe a search for gravitational waves from compact binaries with at least one component with mass 0.2 $M_\odot$--$1.0 M_\odot$ and mass ratio $q \geq 0.1$ in Advanced LIGO and Advanced Virgo data collected between 1 November 2019, 15:00 UTC and 27 March 2020, 17:00 UTC. No signals were detected. The most significant candidate has a false alarm rate of 0.2 $\mathrm{yr}^{-1}$. We estimate the sensitivity of our search over the entirety of Advanced LIGO's and Advanced Virgo's third observing run, and present the most stringent limits to date on the merger rate of binary black holes with at least one subsolar-mass component. We use the upper limits to constrain two fiducial scenarios that could produce subsolar-mass black holes: primordial black holes (PBH) and a model of dissipative dark matter. The PBH model uses recent prescriptions for the merger rate of PBH binaries that include a rate suppression factor to effectively account for PBH early binary disruptions. If the PBHs are monochromatically distributed, we can exclude a dark matter fraction in PBHs $f_\mathrm{PBH} \gtrsim 0.6$ (at 90% confidence) in the probed subsolar-mass range. However, if we allow for broad PBH mass distributions we are unable to rule out $f_\mathrm{PBH} = 1$. For the dissipative model, where the dark matter has chemistry that allows a small fraction to cool and collapse into black holes, we find an upper bound $f_{\mathrm{DBH}} < 10^{-5}$ on the fraction of atomic dark matter collapsed into black holes

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

International audienceGravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects