Autophagy is a key cellular quality control mechanism. Nutrient stress triggers bulk autophagy, which nonselectively degrades cytoplasmic material upon formation and liquid-liquid phase separation of the autophagy-related gene 1 (Atg1) complex. In contrast, selective autophagy eliminates protein aggregates, damaged organelles and other cargoes that are targeted by an autophagy receptor.
View Article and Find Full Text PDFAromatase inhibitors are effective in treating hormone receptor-positive breast cancer, particularly in postmenopausal women. However, the challenges of inconsistent dissolution, variable absorption and side effects with oral administration persist. To address these issues, transdermal delivery has emerged as a viable alternative.
View Article and Find Full Text PDFBackground: The accuracy of movement determination software in current activity trackers is insufficient for scientific applications, which are also not open-source.
Objective: To address this issue, we developed an accurate, trainable, and open-source smartphone-based activity-tracking toolbox that consists of an Android app (HumanActivityRecorder) and 2 different deep learning algorithms that can be adapted to new behaviors.
Methods: We employed a semisupervised deep learning approach to identify the different classes of activity based on accelerometry and gyroscope data, using both our own data and open competition data.
Microscopy has revolutionised our view on biology and has been vital for many discoveries since its invention around 200 years ago. Recent developments in cell biology have led to a strong interest in generating spheroids and organoids that better represent tissue. However, the current challenge faced by many researchers is the culture and analysis of these three-dimensional (3D) cell cultures.
View Article and Find Full Text PDFEncapsulated cell-based therapies involve the use of genetically-modified cells embedded in a material in order to produce a therapeutic agent in a specific location in the patient's body. This approach has shown great potential in animal model systems for treating diseases such as type I diabetes or cancer, with selected approaches having been tested in clinical trials. Despite the promise shown by encapsulated cell therapy, though, there are safety concerns yet to be addressed, such as the escape of the engineered cells from the encapsulation material and the resulting production of therapeutic agents at uncontrolled sites in the body.
View Article and Find Full Text PDFChitosan-collagen blends have been widely applied in tissue engineering, joints diseases treatment, and many other biomedical fields. Understanding the affinity between chitosan and collagen type II is particularly relevant in the context of mechanical properties modulation, which is closely associated with designing biomaterials suitable for cartilage and synovial fluid regeneration. However, many structural features influence chitosan's affinity for collagen.
View Article and Find Full Text PDFConventional synthesis routes for thermoplastic polyurethanes (TPUs) still require the use of isocyanates and tin-based catalysts, which pose considerable safety and environmental hazards. To reduce both the ecological footprint and human health dangers for nonwoven TPU scaffolds, it is key to establish a green synthesis route, which eliminates the use of these toxic compounds and results in biocompatible TPUs with facile processability. In this study, we developed high-molecular-weight nonisocyanate polyurethanes (NIPUs) through transurethanization of 1,6-hexanedicarbamate with polycarbonate diols (PCDLs).
View Article and Find Full Text PDFProtein S-palmitoylation, the addition of a long-chain fatty acid to target proteins, is among the most frequent reversible protein modifications in Metazoa, affecting subcellular protein localization, trafficking and protein-protein interactions. S-palmitoylated proteins are abundant in the neuronal system and are associated with neuronal diseases and cancer. Despite the importance of this post-translational modification, it has not been thoroughly studied in the model organism Drosophila melanogaster.
View Article and Find Full Text PDFIn this study, photo-curing kinetics for urethane-acrylate-based photo-inks for 3D printing were evaluated using a photo-differential scanning calorimetry analysis. Initially, the photopolymerization kinetics of di- and monofunctional monomers were separately studied at different temperatures (5-85 °C). Later, the photo-curing kinetics and mechanical properties of photo-inks based on different monomer mixtures (40/60-20/80) were evaluated.
View Article and Find Full Text PDFThe lubrication mechanism in synovial fluid and joints is not yet fully understood. Nevertheless, intermolecular interactions between various neutral and ionic species including large macromolecular systems and simple inorganic ions are the key to understanding the excellent lubrication performance. An important tool for characterizing the intermolecular forces and their structural consequences is molecular dynamics.
View Article and Find Full Text PDFWith the rising amount of data in the sports and health sectors, a plethora of applications using big data mining have become possible. Multiple frameworks have been proposed to mine, store, preprocess, and analyze physiological vitals data using artificial intelligence and machine learning algorithms. Comparatively, less research has been done to collect potentially high volume, high-quality 'big data' in an organized, time-synchronized, and holistic manner to solve similar problems in multiple fields.
View Article and Find Full Text PDFPancreatic beta cells have inadequate levels of antioxidant enzymes, and the damage induced by oxidative stress poses a challenge for their use in a therapy for patients with type 1 diabetes. It is known that the interaction of the pancreatic endocrine cells with support cells can improve their survival and lead to less vulnerability to oxidative stress. Here we investigated alpha (alpha TC-1), beta (INS1E) and endothelial (HUVEC) cells assembled into aggregates known as pseudoislets as a model of the pancreatic islets of Langerhans.
View Article and Find Full Text PDFBiol Psychiatry Glob Open Sci
January 2022
Background: Bipolar disorder is a severe chronic mental disorder. There is a bidirectional relationship between disease course and circadian phase. Significant circadian phase shifts occur during transitions between episodes, but episodes can also be elicited during euthymia by forced rapid changes in circadian phase.
View Article and Find Full Text PDFLight-inducible gene switches represent a key strategy for the precise manipulation of cellular events in fundamental and applied research. However, the performance of widely used gene switches is limited due to low tissue penetrance and possible phototoxicity of the light stimulus. To overcome these limitations, we engineer optogenetic synthetic transcription factors to undergo liquid-liquid phase separation in close spatial proximity to promoters.
View Article and Find Full Text PDFReproducibility and reusability of the results of data-based modeling studies are essential. Yet, there has been-so far-no broadly supported format for the specification of parameter estimation problems in systems biology. Here, we introduce PEtab, a format which facilitates the specification of parameter estimation problems using Systems Biology Markup Language (SBML) models and a set of tab-separated value files describing the observation model and experimental data as well as parameters to be estimated.
View Article and Find Full Text PDFVascularization is undoubtedly one of the greatest challenges in tissue engineering. Its importance is particularly evident when considering the transplantation of (bioengineered) pancreatic islets of Langerhans, which are highly sensitive to the delivery of oxygen and nutrients for their survival and function. Here we studied pseudoislets of Langerhans, which are three-dimensional spheroids composed of β (INS1E), α (alpha TC-1), and endothelial (HUVEC) cells, and were interested in how the location and prevalence of the different cell types affected the presence of endothelial cells in the pseudoislet.
View Article and Find Full Text PDFBackground: A chronic low-grade inflammatory state appears to be a relevant mechanism in the pathophysiology of bipolar disorder. Pro-inflammatory cytokines may influence disease course and individual symptomatology; and biological markers correlating with illness features may be of utility in clinical decision making during euthymia.
Methods: 51 euthymic outpatients with Bipolar-I-Disorder (BD-I) and 93 healthy controls (HC) were investigated.
Background: Lateral sliding calcaneus osteotomies are common procedures to correct hindfoot varus deformities. Shifting the calcaneal tuberosity laterally (lateralization) can lead to tarsal tunnel pressure increase and tibial nerve palsy. The purpose of this cadaveric biomechanical study was to investigate the correlation of lateralization and pressure increase underneath the flexor retinaculum.
View Article and Find Full Text PDFOptogenetics is the genetic approach for controlling cellular processes with light. It provides spatiotemporal, quantitative and reversible control over biological signaling and metabolic processes, overcoming limitations of chemically inducible systems. However, optogenetics lags in plant research because ambient light required for growth leads to undesired system activation.
View Article and Find Full Text PDFDimerization of the small GTPase Arf is prerequisite for the scission of COPI-coated transport vesicles. Here, we quantify the monomer/dimer equilibrium of Arf within the membrane and show that after membrane scission, Arf dimers are restricted to donor membranes. By hydrogen exchange mass spectrometry, we define the interface of activated dimeric Arf within its switch II region.
View Article and Find Full Text PDFFormation of clathrin-coated vesicles (CCVs) in receptor-mediated endocytosis is a mechanistically well-established process, in which clathrin, the adaptor protein complex AP-2, and the large GTPase dynamin play crucial roles. In order to obtain more mechanistic insight into this process, here we established a giant unilamellar vesicle (GUV)-based in vitro CCV reconstitution system with chemically defined components and the full-length recombinant proteins clathrin, AP-2, epsin-1, and dynamin-2. Our results support the predominant model in which hydrolysis of GTP by dynamin is a prerequisite to generate CCVs.
View Article and Find Full Text PDFInflammation is a complex biological response to stimuli. Activated macrophages induced excessively release of pro-inflammatory cytokines and mediators such as endogenous radical nitric oxide (NO) play a significant role in the progression of multiple inflammatory diseases. Both natural and synthetic chalcones possess a wide range of bioactivities.
View Article and Find Full Text PDFBackground: Multiple lines of evidence suggest that the onset and course of bipolar disorder is influenced by environmental light conditions. Increased suppression of melatonin by light (supersensitivity) in patients with bipolar disorder has been postulated as an endophenotype by several studies. However, due to methodological shortcomings, the results of these studies remain inconclusive.
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