441 research outputs found
Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles ( MISEV ) guidelines for the field in 2014. We now update these MISEV2014 guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points
A benchmark for microRNA quantification algorithms using the OpenArray platform
miRcompData R package source. The source code for the miRcompData R package, also available at: http://bioconductor.org/packages/miRcompData/ . (GZ 8765 kb
Human perivascular stem cells prevent bone graft resorption in osteoporotic contexts by inhibiting osteoclast formation
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Extracellular Vesicle-Associated Aβ Mediates Trans-Neuronal Bioenergetic and Ca\u3csup\u3e2+\u3c/sup\u3e-Handling Deficits in Alzheimer\u27s Disease Models
Alzheimer’s disease (AD) is an age-related neurodegenerative disorder in which aggregation-prone neurotoxic amyloid β-peptide (Aβ) accumulates in the brain. Extracellular vesicles (EVs), including exosomes, are small 50–150 nm membrane vesicles that have recently been implicated in the prion-like spread of self-aggregating proteins. Here we report that EVs isolated from AD patient cerebrospinal fluid and plasma, from the plasma of two AD mouse models, and from the medium of neural cells expressing familial AD presenilin 1 mutations, destabilize neuronal Ca2+ homeostasis, impair mitochondrial function, and sensitize neurons to excitotoxicity. EVs contain a relatively low amount of Aβ but have an increased Aβ42/ Aβ40 ratio; the majority of Aβ is located on the surface of the EVs. Impairment of lysosome function results in increased generation of EVs with elevated Aβ42 levels. EVs may mediate transcellular spread of pathogenic Aβ species that impair neuronal Ca2+ handling and mitochondrial function, and may thereby render neurons vulnerable to excitotoxicity
Towards defining reference materials for extracellular vesicle size, concentration, refractive index and epitope abundance
Accurate characterization of extracellular vesicles (EVs) is critical to
explore their diagnostic and therapeutic applications. As the EV research field
has developed, so too have the techniques used to characterize them. The
development of reference materials is required for the standardization of these
techniques. This work, initiated from the ISEV 2017 Biomarker Workshop in
Birmingham, UK, and with further discussion during the ISEV 2019
Standardization Workshop in Ghent, Belgium, sets out to elucidate which
reference materials are required and which are currently available to
standardize commonly used analysis platforms for characterizing EV size,
concentration, refractive index, and epitope expression. Due to their
predominant use, a particular focus is placed on the optical methods
nanoparticle tracking analysis and flow cytometry.Comment: 30 pages, 6 figures, 2 table
Characterisation and disposability assessment of multi-waste stream in-container vitrified products for higher activity radioactive waste
Materials from GeoMelt® In-Container Vitrification (ICV)™ of simulant UK nuclear wastes were characterised to understand the partitioning of elements, including inactive surrogates for radionuclide species of interest, within the heterogeneous products. Aqueous durability analysis was performed to assess the potential disposability of the resulting wasteforms. The vitrification trial aimed to immobilise a variety of simulant legacy waste streams representative of decommissioning operations in the UK, including plutonium contaminated material, Magnox sludges and ion-exchange materials, which were vitrified upon the addition of glass forming additives. Two trials with different wastes were characterised, with the resultant vitreous wasteforms comprising olivine and pyroxene crystalline minerals within glassy matrices. Plutonium surrogate elements were immobilised within the glassy fraction rather than partitioning into crystalline phases. All vitrified products exhibited comparable or improved durability to existing UK high level waste vitrified nuclear wasteforms over a 28 day period
RNA secondary structure prediction from multi-aligned sequences
It has been well accepted that the RNA secondary structures of most
functional non-coding RNAs (ncRNAs) are closely related to their functions and
are conserved during evolution. Hence, prediction of conserved secondary
structures from evolutionarily related sequences is one important task in RNA
bioinformatics; the methods are useful not only to further functional analyses
of ncRNAs but also to improve the accuracy of secondary structure predictions
and to find novel functional RNAs from the genome. In this review, I focus on
common secondary structure prediction from a given aligned RNA sequence, in
which one secondary structure whose length is equal to that of the input
alignment is predicted. I systematically review and classify existing tools and
algorithms for the problem, by utilizing the information employed in the tools
and by adopting a unified viewpoint based on maximum expected gain (MEG)
estimators. I believe that this classification will allow a deeper
understanding of each tool and provide users with useful information for
selecting tools for common secondary structure predictions.Comment: A preprint of an invited review manuscript that will be published in
a chapter of the book `Methods in Molecular Biology'. Note that this version
of the manuscript may differ from the published versio
Small RNA analysis in Sindbis virus infected human HEK293 cells
In contrast to the defence mechanism of RNA interference (RNAi) in plants and invertebrates, its role in the innate response to virus infection of mammals is a matter of debate. Since RNAi has a well-established role in controlling infection of the alphavirus Sindbis virus (SINV) in insects, we have used this virus to investigate the role of RNAi in SINV infection of human cells
Advancing the use of noncoding RNA in regulatory toxicology: Report of an ECETOC workshop
The European Centre for the Ecotoxicology and Toxicology of Chemicals (ECETOC) organised a workshop to discuss the state-of-the-art research on noncoding RNAs (ncRNAs) as biomarkers in regulatory toxicology and as analytical and therapeutic agents. There was agreement that ncRNA expression profiling data requires careful evaluation to determine the utility of specific ncRNAs as biomarkers. To advance the use of ncRNA in regulatory toxicology, the following research priorities were identified: (1) Conduct comprehensive literature reviews to identify possibly suitable ncRNAs and areas of toxicology where ncRNA expression profiling could address prevailing scientific deficiencies. (2) Develop consensus on how to conduct ncRNA expression profiling in a toxicological context. (3) Conduct experimental projects, including, e.g., rat (90-day) oral toxicity studies, to evaluate the toxicological relevance of the expression profiles of selected ncRNAs. Thereby, physiological ncRNA expression profiles should be established, including the biological variability of healthy individuals. To substantiate the relevance of key ncRNAs for cell homeostasis or pathogenesis, molecular events should be dose-dependently linked with substance-induced apical effects. Applying a holistic approach, knowledge on ncRNAs, 'omics and epigenetics technologies should be integrated into adverse outcome pathways to improve the understanding of the functional roles of ncRNAs within a regulatory context
Do adults with high functioning autism or Asperger Syndrome differ in empathy and emotion recognition?
The present study examined whether adults with high functioning autism (HFA) showed greater difficulties in (i) their self-reported ability to empathise with others and/or (ii) their ability to read mental states in others’ eyes than adults with Asperger syndrome (AS). The Empathy Quotient (EQ) and ‘Reading the Mind in the Eyes’ Test (Eyes Test) were compared in 43 adults with AS and 43 adults with HFA. No significant difference was observed on EQ score between groups, while adults with AS performed significantly better on the Eyes Test than those with HFA. This suggests that adults with HFA may need more support, particularly in mentalizing and complex emotion recognition, and raises questions about the existence of subgroups within autism spectrum conditions
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