Репозиторий Университета

The application of microfluidic systems in chemical and biological assays has progressed dramatically in recent years. One of the fundamental operations that microfluidic devices must achieve is a high mixing index. Of particular importance is the role of planar mixing units with repetitive obstacles (MURO) in the formation of micromixers. To date, a myriad of planar passive micromixers has been proposed. However, a strategy for the combination of these units to find an efficient planar mixer has not been investigated. As such, five different MURO have been selected to form a “hybrid micromixer,” and their combination was evaluated via numerical and experimental methods. These mixing units include ellipse-like, Tesla, nozzle and pillar, teardrop, and obstruction in a curved mixing unit. Since these units have distinctive dimensions, dynamic and geometric similarities were used to scale and connect them. Afterwards, six slots were designated to house each mixing unit. Since the evaluation of all possible unit configurations is not feasible, the design of experiment method is applied to reduce the total number of experiments from 15 625 to 25. Following this procedure, the “hybrid” micromixer proposed here, comprising Tesla, nozzle and pillar, and obstruction units, shows improved performance for a wide range of Re (i.e., mixing index of >90% for Re 0.001–0.1, 22–45) over existing designs. The use of velocity profiles, concentration diagrams, vorticity and circulation plots assist in the analysis of each unit. Comparison of the proposed “hybrid” micromixer with other obstacle-based planar micromixers demonstrates improved performance, indicating the combination of planar mixing units is a useful strategy for building high-performance micromixers.

Lung cancer affects over 1. 8 million people worldwide and is the leading cause of cancer related mortality globally. Currently, diagnosis of lung cancer involves a combination of imaging and invasive biopsies to confirm histopathology. Non-invasive diagnostic techniques under investigation include “liquid biopsies” through a simple blood draw to develop predictive and prognostic biomarkers. A better understanding of circulating tumor cell (CTC) dissemination mechanisms offers promising potential for the development of techniques to assist in the diagnosis of lung cancer. Enumeration and characterization of CTCs has the potential to act as a prognostic biomarker and to identify novel drug targets for a precision medicine approach to lung cancer care. This review will focus on the current status of CTCs and their potential diagnostic and prognostic utility in this setting.

Рецепторы, активируемые пролифератором пероксисом (PPAR), являются рецепторами ядерных гормонов, которые связываются с ДНК и регулируют транскрипцию генов, участвующих в метаболизме липидов и глюкозы. Растущее число исследований предоставляет убедительные доказательства того, что PPAR являются многообещающими фармакологическими мишенями для терапевтического вмешательства при различных заболеваниях, включая сердечно-сосудистые нарушения, вызванные нарушением энергетического обмена. Агонисты PPAR широко использовались в течение десятилетий в качестве гиполипидемических и противовоспалительных средств. Существующие исследования в основном сфокусированы на антиатеросклеротическом действии агонистов PPAR; однако их роль в поддержании клеточной биоэнергетики остается неясной. Недавние исследования на животных моделях и пациентах показывают, что агонисты PPAR могут нормализовать липидный обмен, стимулируя окисление жирных кислот. Эти исследования указывают на важность выяснения агонистов PPAR как потенциальных фармакологических агентов для защиты сердца от энергетической недостаточности. Здесь мы суммируем и предоставляем всесторонний анализ предыдущих исследований о роли PPAR в сердце при нормальных и патологических состояниях. Кроме того, в обзоре рассматриваются PPAR в качестве терапевтической мишени и полезные эффекты агонистов PPAR, в частности безафибрата, для ослабления кардиомиопатии и сердечной недостаточности у пациентов и на животных моделях.

Chronic hepatitis B virus (HBV) infection has long remained a critical global health issue. Covalently closed circular DNA (cccDNA) is a persistent form of the HBV genome that maintains HBV chronicity. Decades of extensive research resulted in the two therapeutic options currently available: nucleot(s)ide analogs and interferon (IFN) therapy. A plethora of reliable markers to monitor HBV patients has been established, including the recently discovered encapsidated pregenomic RNA in serum, which can be used to determine treatment end-points and to predict the susceptibility of patients to IFN. Additionally, HBV RNA splice variants and cccDNA and its epigenetic modifications are associated with the clinical course and risks of hepatocellular carcinoma (HCC) and liver fibrosis. However, new antivirals, including CRISPR/Cas9, APOBEC-mediated degradation of cccDNA, and T-cell therapies aim at completely eliminating HBV, and it is clear that the diagnostic arsenal for defining the long-awaited sterilizing cure is missing. In this review, we discuss the currently available tools for detecting and measuring HBV RNAs and cccDNA, as well as the state-of-the-art in clinical implications of these markers, and debate needs and goals within the context of the sterilizing cure that is soon to come. View Full-Text

Oral colon-specific delivery systems emerged as the main therapeutic cargos by making a significant impact in the field of modern medicine for local drug delivery in intestinal inflammation. The site-specific delivery of therapeutics (aminosalicylates, glucocorticoids, biologics) to the ulcerative mucus tissue can provide prominent advantages in mucosal healing (MH). Attaining gut mucosal healing and anti-fibrosis are main treatment outcomes in inflammatory bowel disease (IBD). The pharmaceutical strategies that are commonly used to achieve a colon-specific drug delivery system include time, pH-dependent polymer coating, prodrug, colonic microbiota-activated delivery systems and a combination of these approaches. Amongst the different approaches reported, the use of biodegradable polysaccharide coated systems holds great promise in delivering drugs to the ulcerative regions. The present review focuses on major physiological gastro-intestinal tract challenges involved in altering the pharmacokinetics of delivery systems, pathophysiology of MH and fibrosis, reported drug-polysaccharide cargos and focusing on conventional to advanced disease responsive delivery strategies, highlighting their limitations and future perspectives in intestinal inflammation therapy.

Background Nonhuman primates (NHP) may provide the most adequate (in terms of neuroanatomy and neurophysiology) model of spinal cord injury (SCI) for testing regenerative therapies, but bioethical considerations exclude their use in severe SCI. New Method A reproducible model of SCI at the lower thoracic level has been developed in Rhesus macaques. The model comprises surgical resection of 25% of the spinal cord in the projection of the dorsal funiculus and dorsolateral corticospinal pathways, controlled via registration of intraoperative evoked potentials (EPs). The animals were evaluated using the modified Hindlimb score, MRI, SSEP, and MEP over a time period of 8–12 weeks post-SCI, followed by histological examination. Results Complete disappearance of intraoperative EPs from distal hindlimb muscles without restoration within two weeks post-SCI was an indicator for irreversible disruption of the abovementioned pathways. As a result, controlled damage to the spinal cord was achieved in three NHPs, clinically manifested as irreversible lower monoplegia. No significant functional restoration was observed in these NHPs up to 12 weeks post-SCI. Demyelination of the damaged ascending tracts was detected. Disturbances in pelvic organ function were not observed in all animals. Comparison with existing methods The new method of EPs-guided SCI allows a more controlled and irreversible damage to the spinal cord compared with contusion and other transection approaches. Conclusions This method to induce complete SCI in NHP is well tolerated, reproducible and ethically acceptable: these are valuable attributes in a preclinical model that will hopefully help advance testing of new regenerative therapies in SCI.

Подсчитано, что два миллиона новых зубных имплантатов устанавливаются по всему миру каждый год. Инновационные материалы для имплантатов разработаны для того, чтобы минимизировать риск воспалений на периимплантатах. Широкий спектр испытаний материалов проводится с использованием стандартных 2D, терминальных и инвазивных методов. Примененные методы недостаточны для контроля всей поверхности имплантата и временного прогресса. Поэтому мы построили трехмерную модель периимплантата с использованием цилиндрического имплантата, колонизированного фибробластами десны человека. Для того чтобы отслеживать реакцию клеток с течением времени, было установлено нетоксичное окрашивание LIVE / DEAD, которое было применено к новой 3D-модели. Наш метод окрашивания LIVE / DEAD в сочетании с трехмерной визуализацией с временным разрешением с использованием сканирующей лазерной оптической томографии (SLOT), позволили нам отслеживать путь гибели клеток вдоль имплантата в трехмерной модели периимплантата. Окрашивание живых и мертвых фибробластов десны в ответ на токсичность эффективно подтверждалось окрашиванием LIVE / DEAD. Кроме того, можно было визуализировать весь имплантированный в клетку имплантат в 3D и до 63 часов. Эта новая методология дает возможность регистрировать долговременный клеточный ответ на внешние факторы стресса вдоль зубного имплантата и, таким образом, оценивать эффективность новых материалов / поверхностей.

Maintaining the epithelial status of cells in vitro and fabrication of a multilayered epithelial lining is one of the key problems in the therapy using cell technologies. When cultured in a monolayer, epithelial cells change their phenotype from epithelial to epithelial-mesenchymal or mesenchymal that makes it difficult to obtain a sufficient number of cells in a 2D culture and to use them in tissue engineering. Here, using buccal epithelial cells from the oral mucosa, we developed a novel approach to recover and maintain the stable cell phenotype and form a multilayered epithelial lining in vitro via the 2D/3D cell self-assembling. Transitioning the cells from the monolayer to non-adhesive 3D culture conditions led to formation of self-assembling spheroids, with restoration of their epithelial characteristics after epithelial-mesenchymal transition. In 7 days, the cells within spheroids restored the apical-basal polarity, and the formation of both tight (ZO1) and adherent (E-cadherin) intercellular junctions was shown. Thus, culturing buccal epithelial cells in a 3D system allowed us to recover and durably maintain the morphological and functional characteristics of epithelial cells. The multilayered epithelial lining formation was achieved after placing spheroids for 7 days onto a hybrid matrix, which consisted of collagen layers and reinforcing poly (lactide-co-glycolide) fibers and was proven promising for replacement of the urothelium. Thus, we offer an effective technique of forming multilayered epithelial linings on carrier-matrices using cell spheroids that was not previously described elsewhere and can find a wide range of applications in tissue engineering, replacement surgery, and regenerative medicine.

Количественное измерение рН и градиентов метаболитов с помощью микроскопии является одной из задач при производстве карбоорганических органоидов и многоклеточных агрегатов. Здесь мы использовали целлюлозосвязывающий домен (CBD) белка Cellulomonas fimi CenA для создания биосенсорных каркасов, которые позволяют измерять pH и Ca 2+.градиенты по интенсивности флуоресценции и режимам обнаружения времени жизни (FLIM). Путем слияния CBD с pH-чувствительным улучшенным голубым флуоресцентным белком (CBD-ECFP) мы добились эффективной маркировки каркасов на основе целлюлозы, основанных на нанофибриллах, бактериальной целлюлозе и децеллюляризованных растительных материалах. CBD-ECFP, связанный с целлюлозными матрицами, продемонстрировал чувствительность к pH, сопоставимую с немеченым ECFP (1,9-2,3 нс для pH 6-8), что делает его совместимым с анализом внеклеточного pH на основе FLIM. Используя 3D-культуру раковых клеток толстой кишки человека (HCT116) и кишечных органоидов мышей, полученных из стволовых клеток взрослых, мы оценили полезность полученных биосенсорных каркасов. CBD-ECFP был чувствителен к увеличению внеклеточного подкисления: результаты показали снижение на 0,2-0,4 единиц pH в ответ на деполяризацию мембраны протонофором FCCP. На модели кишечных органоидов мы продемонстрировали многопараметрическую визуализацию, комбинируя внеклеточное подкисление (FLIM) с мониторингом оксигенации клеток на основе фосфоресцентного зонда. Описанная стратегия мечения позволяет создавать внеклеточные pH-чувствительные каркасы для многопараметрических анализов FLIM и их использования в тканях живого рака и стволовых клеток. В совокупности это исследование может помочь в достижении контролируемого биофабрикации трехмерных моделей тканей с известными метаболическими характеристиками. ЗАЯВЛЕНИЕ О ЗНАЧЕНИИ: Мы разработали биосенсоры, состоящие из целлюлозо-связывающего домена (CBD) и pH- и Ca Описанная стратегия мечения позволяет создавать внеклеточные pH-чувствительные каркасы для многопараметрических анализов FLIM и их использования в тканях живого рака и стволовых клеток. В совокупности это исследование может помочь в достижении контролируемого биофабрикации трехмерных моделей тканей с известными метаболическими характеристиками. ЗАЯВЛЕНИЕ О ЗНАЧЕНИИ: Мы разработали биосенсоры, состоящие из целлюлозо-связывающего домена (CBD) и pH- и Ca Описанная стратегия мечения позволяет создавать внеклеточные pH-чувствительные каркасы для многопараметрических анализов FLIM и их использования в тканях живого рака и стволовых клеток. В совокупности это исследование может помочь в достижении контролируемого биофабрикации трехмерных моделей тканей с известными метаболическими характеристиками. ЗАЯВЛЕНИЕ О ЗНАЧЕНИИ: Мы разработали биосенсоры, состоящие из целлюлозо-связывающего домена (CBD) и pH- и Ca2+ -чувствительные флуоресцентные белки. Биодатчики с меткой CBD эффективно маркируют различные типы целлюлозных матриц, включая нанофибриллярную целлюлозу и децеллюляризованные растительные материалы. Гибридные биосенсорные целлюлозные каркасы, разработанные в этом исследовании, были успешно протестированы многопараметрической FLIM-микроскопией в 3D-культурах раковых клеток и кишечных органоидов мыши.

The purpose of this work was to evaluate the protein and mRNA expression levels of multiple cytoskeletal proteins in the cardiac and lung tissue of mice that were euthanized onboard the United States Orbital Segment of the International Space Station 37 days after the start of the SpaceX-4 mission (September 2014, USA). The results showed no changes in the cytoskeletal protein content in the cardiac and lung tissue of the mice, but there were significant changes in the mRNA expression levels of the associated genes, which may be due to an increase in total genome methylation. The mRNA expression levels of DNA methylases, the cytosine demethylases Tet1 and Tet3, histone acetylase and histone deacetylase did not change, and the mRNA expression level of cytosine demethylase Tet2 was significantly decreased.

Background/Aims: Changes in the external mechanical field result in cytoskeleton reorganization and the formation of adaptive patterns in different types of cells, including somatic cells and sex cells. The aim of this research was to study the protein and mRNA content of cytoskeletal and sperm-specific genes in the sperm and testis cells of mice. Methods: Mice were subjected to 30 days of antiorthostatic suspension to simulate weightlessness, followed by 12 h of recovery, while receiving essential phospholipids at a dosage of 500 mg/kg/day (30HSE and 30HSE+12h groups) or a similar dosage of a placebo (30HS and 30HS+12h groups). Accordingly, reference groups (CE group and C group) were formed. The total number and the percentage of motile spermatozoa were calculated using a Makler chamber. To analyze the number of viable spermatozoa and the permeability of their membranes, eosin staining was used as well as Diff-Quick for a morphological evaluation. Relative protein and mRNA content was estimated in a western blot and quantitative PCR assay, respectively. Results: The relative protein expression levels of actin (beta and gamma) and two alpha-actinin isoforms (1 and 4) remained constant in the sperm of all study groups, except for the 30HS+12h group, where the alpha-actinin-4 level was 13% higher than in the reference group (p < 0.1). In the testis cells, the relative actin isoform content was equivalent to that in the spermatozoa. However, in the testis cells, the ACTN1 mRNA content was 17% higher in the 30HS group than in the C group (p < 0.05), and decreased after 12 h of recovery. In contrast, the ACTN4 mRNA content was 20% lower in the 30HS group than in the reference group (p < 0.05) and increased after the 12-h recovery period. At the same time, in the group administered the essential phospholipids, the relative ACTN1 and ACTN4 mRNA content did not differ from those of the reference group. The relative beta-tubulin content was similar in the reference C group and the reference CE group, which was administered the essential phospholipids. In the 30HS and 30HS+12h groups, the beta-tubulin content decreased by 19% and 22% (p < 0.05), respectively, and they also decreased in the groups administered the essential phospholipids (30HSE and 30HSE+12h groups, by 27% and 33%, respectively, p < 0.05). In the testis tissue, the relative tubulin content did not change in any of the experimental groups. At the same time, the relative mRNA content of the genes encoding the studied cytoskeletal proteins increased, which may indicate the protein content was regulated mainly at the translational level. Conclusion: The spermogram parameters and the content of the sperm-specific proteins and the associated mRNAs revealed a decrease in the number of mature spermatozoa in mice suspended under conditions of weightlessness. Moreover, the decrease was prevented by the administration of essential phospholipids.

Пептид, связанный с геном кальцитонина, играет важную роль в патофизиологии мигрени. Эренумаб, человеческое моноклональное антитело, которое ингибирует пептидный рецептор, связанный с геном кальцитонина, оценивается для предотвращения мигрени.

Articular hyaline cartilage is extensively hydrated, but it is neither innervated nor vascularized, and its low cell density allows only extremely limited self-renewal. Most clinical and research efforts currently focus on the restoration of cartilage damaged in connection with osteoarthritis or trauma. Here, we discuss current clinical approaches for repairing cartilage, as well as research approaches which are currently developing, and those under translation into clinical practice. We also describe potential future directions in this area, including tissue engineering based on scaffolding and/or stem cells as well as a combination of gene and cell therapy. Particular focus is placed on cell-based approaches and the potential of recently characterized chondro-progenitors; progress with induced pluripotent stem cells is also discussed. In this context, we also consider the ability of different types of stem cell to restore hyaline cartilage and the importance of mimicking the environment in vivo during cell expansion and differentiation into mature chondrocytes.

The heme in the active center of peroxidases reacts with hydrogen peroxide to form highly reactive intermediates, which then oxidize simple substances called peroxidase substrates. Human peroxidases can be divided into two groups: (1) True peroxidases are enzymes whose main function is to generate free radicals in the peroxidase cycle and (pseudo)hypohalous acids in the halogenation cycle. The major true peroxidases are myeloperoxidase, eosinophil peroxidase and lactoperoxidase. (2) Pseudo-peroxidases perform various important functions in the body, but under the influence of external conditions they can display peroxidase-like activity. As oxidative intermediates, these peroxidases produce not only active heme compounds, but also protein-based tyrosyl radicals. Hemoglobin, myoglobin, cytochrome c/cardiolipin complexes and cytoglobin are considered as pseudo-peroxidases. Рeroxidases play an important role in innate immunity and in a number of physiologically important processes like apoptosis and cell signaling. Unfavorable excessive peroxidase activity is implicated in oxidative damage of cells and tissues, thereby initiating the variety of human diseases. Hence, regulation of peroxidase activity is of considerable importance. Since peroxidases differ in structure, properties and location, the mechanisms controlling peroxidase activity and the biological effects of peroxidase products are specific for each hemoprotein. This review summarizes the knowledge about the properties, activities, regulations and biological effects of true and pseudo-peroxidases in order to better understand the mechanisms underlying beneficial and adverse effects of this class of enzymes. View Full-Text

ARC Centre of Excellence for Nanoscale Biophotonics, Faculty of Science and Engineering, Macquarie University, North Ryde, 2109, New South Wales, Australia. Liposomes have been well established as an effective drug delivery system, due to simplicity of their preparation and unique characteristics. However conventional liposomes are unsuitable for the on-demand content release, which limits their therapeutic utility. Here we report X-ray-triggerable liposomes incorporating gold nanoparticles and photosensitizer verteporfin. The 6 MeV X-ray radiation induces verteporfin to produce singlet oxygen, which destabilises the liposomal membrane and causes the release of cargos from the liposomal cavity. This triggering strategy is demonstrated by the efficiency of gene silencing in vitro and increased effectiveness of chemotherapy in vivo. Our work indicates the feasibility of a combinatorial treatment and possible synergistic effects in the course of standard radiotherapy combined with chemotherapy delivered via X-ray-triggered liposomes. Importantly, our X-ray-mediated liposome release strategy offers prospects for deep tissue photodynamic therapy, by removing its depth limitation.

Upconversion nanoparticles (UCNPs) coated with polyethylenimine (PEI) are popular background-free optical contrast probes and efficient drug and gene delivery agents attracting attention in science, industry and medicine. Their unique optical properties are especially useful for subsurface nanotheranostics applications, in particular, in skin. However, high cytotoxicity of PEI limits safe use of UCNP@PEI and this represents a major barrier for clinical translation of UCNP@PEI-based technologies. Our study aims to overcome this problem by exploring additional surface modifications to UCNP@PEI to create biocompatible and functional nanotheranostic materials. We designed and synthesized six types of layered polymer coatings that envelop the original UCNP@PEI surface, five of which reduced the cytotoxicity to human skin keratinocytes under acute (24h) and subacute (120h) exposure. In parallel, we examined the photoluminescence spectra and lifetime of the surface modified UCNP@PEI. To quantify their brightness, we developed original methodology to precisely measure the colloidal concentration to normalize the photoluminescence signal using a non-digesting mass spectrometry protocol. Our results, specified for the individual coatings, show that despite beneficial effect on biocompatibility, the external polymer coatings of UCNP@PEI quench the upconversion photoluminescence in biologically relevant aqueous environments. This trade-off between cytotoxicity and brightness for surface-coated UCNPs emphasizes the need for the combined assessment of biocompatibility and photophysical properties of post-modification UCNPs. We present an optimised methodology for rational surface design of UCNP@PEI in biologically relevant conditions, which is essential to facilitate the translation of such nanoparticles to the clinical applications.

Микробициды являются антисептическими топическими лекарственными средствами, способствующими напрямую или опосредованно сдерживать проникновение инфекционного агента в организм
человека, тем самым предотвращая половую передачу вируса иммунодефицита человека (ВИЧ) и
других заболеваний, передающихся половым путем. Они обладают не только прямым местным противовирусным механизмом действия при половой передаче ВИЧ, но и влияют на компоненты мукозального иммунитета во влагалище.
В данной статье авторами рассмотрены фармацевтические и биомедицинские аспекты применения
кандидатных микробицидов, представлены разнообразные классификации ýтих препаратов, описаны наиболее значимые представители каждой химической группы, указаны механизмы их действия.
Помимо ýтого даны представления о структуре и функции мукозального иммунитета и показана
значимость мукозального иммунного ответа на вирус при половой передаче ВИЧ-инфекции. Отдельно рассматриваются ýкспериментальные модели, которые применяются для тестирования кандидатных микробицидов. Для каждого описанного в статье химического соединения представлен
краткий обзор доклинических и клинических исследований по разработке на его основе микробицида. Даны общие представления о таком новом разнообразном классе медицинских иммунобиологических препаратов, как микробициды, которые должны в ближайшем будущем уменьшить
риск половой передачи ВИЧ и сдержать ýпидемию ВИЧ-инфекции и синдрома приобретенного
иммунодефицита (СПИД).

The relapse rate in antiphospholipid syndrome (APS) remains high, i.e. around 20%–21% at 5 years in thrombotic APS and 20–28% in obstetrical APS [2, 3]. Hydroxychloroquine (HCQ) appears as an additional therapy, as it possesses immunomodulatory and anti-thrombotic various effects [4–16]. Our group recently obtained the orphan designation of HCQ in antiphospholipid syndrome by the European Medicine Agency. Furthermore, the leaders of the project made the proposal of an international project, HIBISCUS, about the use of Hydroxychloroquine in secondary prevention of obstetrical and thrombotic events in primary APS. This study has been launched in several countries and at now, 53 centers from 16 countries participate to this international trial. This trial consists in two parts: a retrospective and a prospective study. The French part of the trial in thrombosis has been granted by the French Minister of Health in December 2015 (the academic trial independent of the pharmaceutical industry PHRC N PAPIRUS) and is coordinated by one of the members of the leading consortium of HIBISCUS.