498 research outputs found
Correlations between arm motor behavior and brain function following bilateral arm training after stroke:A systematic review
Background Bilateral training (BT) of the upper limb (UL) might enhance recovery of arm function after stroke. To better understand the therapeutic potential of BT, this study aimed to determine the correlation between arm motor behavior and brain structure/function as a result of bilateral arm training poststroke. Methods A systematic review of quantitative studies of BT evaluating both UL motor behavior and neuroplasticity was conducted. Eleven electronic databases were searched. Two reviewers independently selected studies, extracted data and assessed methodological quality, using the Effective Public Health Practice Project (EPHPP) tool. Results Eight studies comprising 164 participants met the inclusion criteria. Only two studies rated “strong” on the EPHPP tool. Considerable heterogeneity of participants, BT modes, comparator interventions and measures contraindicated pooled outcome analysis. Modes of BT included: in-phase and anti-phase; functional movements involving objects; and movements only. Movements were mechanically coupled, free, auditory-cued, or self-paced. The Fugl-Meyer Assessment (UL section) was used in six of eight studies, however, different subsections were used by different studies. Neural correlates were measured using fMRI and TMS in three and five studies, respectively, using a wide variety of variables. Associations between changes in UL function and neural plasticity were inconsistent and only two studies reported a statistical correlation following BT. Conclusions No clear pattern of association between UL motor and neural response to BT was apparent from this review, indicating that the neural correlates of motor behavior response to BT after stroke remain unknown. To understand the full therapeutic potential of BT and its different modes, further investigation is required
Quantification of the Frequency and Multiplicity of Infection of Respiratory- and Lymph Node–Resident Dendritic Cells During Influenza Virus Infection
Background: Previous studies have demonstrated that DC differentially regulate influenza A virus (IAV)–specific CD8 T cell responses in vivo during high and low dose IAV infections. Furthermore, in vitro infection of DC with IAV at low versus high multiplicities of infection (MOI) results in altered cytokine production and a reduced ability to prime naïve CD8 T cell responses. Flow cytometric detection of IAV proteins within DC, a commonly used method for detection of cellular IAV infection, does not distinguish between the direct infection of these cells or their uptake of viral proteins from dying epithelial cells. Methods/Principal Findings: We have developed a novel, sensitive, single-cell RT-PCR–based approach to assess the infection of respiratory DC (rDC) and lymph node (LN)-resident DC (LNDC) following high and low dose IAV infections. Our results show that, while a fraction of both rDC and LNDC contain viral mRNA following IAV infection, there is little correlation between the percentage of rDC containing viral mRNA and the initial IAV inoculum dose. Instead, increasing IAV inoculums correlate with augmented rDC MOI. Conclusion/Significance: Together, our results demonstrate a novel and sensitive method for the detection of direct IAV infection at the single-cell level and suggest that the previously described ability of DC to differentially regulate IAV-specific T cell responses during high and low dose IAV infections could relate to the MOI of rDC within the LN rather than th
Protease-activated receptor-2 mediates the expression of inflammatory cytokines, antimicrobial peptides, and matrix metalloproteinases in keratinocytes in response to Propionibacterium acnes
Propionibacterium acnes (P. acnes) has been known to produce various exogenous proteases, however, their role in acne pathogenesis remains largely unknown. Proteases elicit cellular responses, at least in part, via proteinase-activated receptor-2 (PAR-2), which is known to mediate inflammation and immune response. In this study, we investigated whether proteases from P. acnes could activate PAR-2 on keratinocytes and induce pro-inflammatory cytokines, antimicrobial peptides (AMPs), and matrix metalloproteinases (MMPs) via PAR-2 signaling. We examined PAR-2 expression and protease activity in acne lesions using immunofluorescence staining and in situ zymography. The effect of the culture supernatant of P. acnes on Ca2+ signaling in immortalized keratinocytes (HaCaT) was measured using a fluorescence method. HaCaT cells were treated with P. acnes strain ATCC 6919 culture supernatant, with or without pretreatment with serine protease inhibitor or selective PAR-2 antagonist and the gene expression of pro-inflammatory cytokines, AMPs, and MMPs was detected using real-time reverse transcription-polymerase chain reaction. We found that the protease activity and PAR-2 expression were increased in acne lesions. The P. acnes culture supernatant induced calcium signaling in keratinocytes via PAR-2 and stimulated the mRNA expression of interleukin (IL)-1α, -8, tumor necrosis factor (TNF)-α, human beta defensin (hBD)-2, LL-37, MMP-1, -2, -3, -9, and -13 in keratinocytes, which was significantly inhibited by serine protease inhibitor as well as selective PAR-2 specific antagonist. These results indicate that PAR-2 plays an important role in the pathogenesis of acne by inducing inflammatory mediators in response to proteases secreted from P. acnes
RNA-seq analysis and compound screening highlight multiple signalling pathways regulating secondary cell death after acute CNS injury in vivo
Perspectives and Potential Applications of Mitochondria-Targeted Antioxidants in Cardiometabolic Diseases and Type 2 Diabetes
There is abundant evidence to suggest that mitochondrial dysfunction is a main cause of insulin resistance and related cardiometabolic comorbidities. On the other hand, insulin resistance is one of the main characteristics of type 2 diabetes, obesity, and metabolic syndrome. Lipid and glucose metabolism require mitochondria to generate energy, and when O2 consumption is low due to inefficient nutrient oxidation, there is an increase in reactive oxygen species, which can impair different types of molecules, including DNA, lipids, proteins, and carbohydrates, thereby inducing proinflammatory processes. Factors which contribute to mitochondrial dysfunction, such as mitochondrial biogenesis and genetics, can also lead to insulin resistance in different insulin-target tissues, and its association with mitochondrial dysfunction can culminate in the development of cardiovascular diseases. In this context, therapies that improve mitochondrial function may also improve insulin resistance. This review explains mechanisms of mitochondrial function related to the pathological effects of insulin resistance in different tissues. The pathogenesis of cardiometabolic diseases will be explained from a mitochondrial perspective and the potential beneficial effects of mitochondria-targeted antioxidants as a therapy for modulating mitochondrial function in cardiometabolic diseases, especially diabetes, will also be considered.Contract grant sponsor: PI10/1195; Contract grant sponsor: PI 12/1984; Contract grant sponsor: CIBERehd CB06/04/0071; Contract grant sponsor: PROMETEO 2010/060; Contract grant sponsor: ACOMP/2012/042; Contract grant sponsor: ACOMP/2012/045; Contract grant sponsor: ACOMP2013/061; Contract grant sponsor: European Regional Development Fund (ERDF)
ORegAnno: an open-access community-driven resource for regulatory annotation
ORegAnno is an open-source, open-access database and literature curation system for community-based annotation of experimentally identified DNA regulatory regions, transcription factor binding sites and regulatory variants. The current release comprises 30 145 records curated from 922 publications and describing regulatory sequences for over 3853 genes and 465 transcription factors from 19 species. A new feature called the ‘publication queue’ allows users to input relevant papers from scientific literature as targets for annotation. The queue contains 4438 gene regulation papers entered by experts and another 54 351 identified by text-mining methods. Users can enter or ‘check out’ papers from the queue for manual curation using a series of user-friendly annotation pages. A typical record entry consists of species, sequence type, sequence, target gene, binding factor, experimental outcome and one or more lines of experimental evidence. An evidence ontology was developed to describe and categorize these experiments. Records are cross-referenced to Ensembl or Entrez gene identifiers, PubMed and dbSNP and can be visualized in the Ensembl or UCSC genome browsers. All data are freely available through search pages, XML data dumps or web services at: http://www.oreganno.org
Coenzyme Q10 Reduces Ethanol-Induced Apoptosis in Corneal Fibroblasts
Dilute ethanol (EtOH) is a widely used agent to remove the corneal epithelium during the modern refractive surgery. The application of EtOH may cause the underlying corneal fibroblasts to undergo apoptosis. This study was designed to investigate the protective effect and potential mechanism of the respiratory chain coenzyme Q10 (CoQ10), an electron transporter of the mitochondrial respiratory chain and a ubiquitous free radical scavenger, against EtOH-induced apoptosis of corneal fibroblasts. Corneal fibroblasts were pretreated with CoQ10 (10 µM) for 2 h, followed by exposure to different concentrations of EtOH (0.4, 2, 4, and 20%) for 20 s. After indicated incubation period (2–12 h), MTT assay was used to examine cell viability. Treated cells were further assessed by flow cytometry to identify apoptosis. Reactive oxygen species (ROS) and the change in mitochondrial membrane potential were assessed using dichlorodihydrofluorescein diacetate/2′,7′-dichlorofluorescein (DCFH-DA/DCF) assays and flow-cytometric analysis of JC-1 staining, respectively. The activity and expression of caspases 2, 3, 8, and 9 were evaluated with a colorimetric assay and western blot analysis. We found that EtOH treatment significantly decreased the viability of corneal fibroblasts characterized by a higher percentage of apoptotic cells. CoQ10 could antagonize the apoptosis inducing effect of EtOH. The inhibition of cell apoptosis by CoQ10 was significant at 8 and 12 h after EtOH exposure. In EtOH-exposed corneal fibroblasts, CoQ10 pretreatment significantly reduced mitochondrial depolarization and ROS production at 30, 60, 90, and 120 min and inhibited the activation and expression of caspases 2 and 3 at 2 h after EtOH exposure. In summary, pretreatment with CoQ10 can inhibit mitochondrial depolarization, caspase activation, and cell apoptosis. These findings support the proposition that CoQ10 plays an antiapoptotic role in corneal fibroblasts after ethanol exposure
Width of Gene Expression Profile Drives Alternative Splicing
Alternative splicing generates an enormous amount of functional and proteomic diversity in metazoan organisms. This process is probably central to the macromolecular and cellular complexity of higher eukaryotes. While most studies have focused on the molecular mechanism triggering and controlling alternative splicing, as well as on its incidence in different species, its maintenance and evolution within populations has been little investigated. Here, we propose to address these questions by comparing the structural characteristics as well as the functional and transcriptional profiles of genes with monomorphic or polymorphic splicing, referred to as MS and PS genes, respectively. We find that MS and PS genes differ particularly in the number of tissues and cell types where they are expressed.We find a striking deficit of PS genes on the sex chromosomes, particularly on the Y chromosome where it is shown not to be due to the observed lower breadth of expression of genes on that chromosome. The development of a simple model of evolution of cis-regulated alternative splicing leads to predictions in agreement with these observations. It further predicts the conditions for the emergence and the maintenance of cis-regulated alternative splicing, which are both favored by the tissue specific expression of splicing variants. We finally propose that the width of the gene expression profile is an essential factor for the acquisition of new transcript isoforms that could later be maintained by a new form of balancing selection
Developing Creativity to Enhance Human Potential in Sport: A Wicked Transdisciplinary Challenge
© Copyright © 2019 Vaughan, Mallett, Davids, Potrac and López-Felip. The challenge of developing creativity to enhance human potential is conceptualized as a multifaceted wicked problem due to the countless interactions between people and environments that constitute human development, athletic skill, and creative moments. To better comprehend the inter-relatedness of ecologies and human behaviors, there have been increasing calls for transdisciplinary approaches and holistic ecological models. In this paper we explore an ecological dynamics rationale for creativity, highlighting the conceptual adjacency of key concepts from transdisciplinarity, dynamic systems theory, ecological psychology and social-cognitive psychology. Our aim is to extend the scope of ecological dynamics and contextualize the application of non-linear pedagogy in sport. Foregrounding the role of sociocultural constraints on creative behaviors, we characterize the athlete-environment system as an ecological niche that arises from, and simultaneously co-creates, a form of life. We elaborate the notion that creative moments, skill and more generally talent in sport, are not traits possessed by individuals alone, but rather can be conceived as properties of the athlete-environment system shaped by changing constraints. This re-conceptualization supports a pedagogical approach predicated on notions of athletes and sports teams as complex adaptive systems. In such systems, continuous non-linear interactions between system components support the exploration of fluent and flexibly creative performance solutions by athletes and sports teams. The implications for practice suggest that cultivating a constellation of constraints can facilitate adaptive exploration of novel affordances (opportunities/invitation for action), fostering creative moments and supporting creative development in athletes. Future models or frameworks for practice contend that pedagogies should emerge from, and evolve in, interaction with the sociocultural context in which practitioners and athletes are embedded
Dark Matter Evidence, Particle Physics Candidates and Detection Methods
The problem of the dark matter in the universe is reviewed. A short history
of the subject is given, and several of the most obvious particle candidates
for dark matter are identified. Particular focus is given to weakly
interacting, massive particles (WIMPs) of which the lightest supersymmetric
particle is an interesting special case and a usful template. The three
detection methods: in particle accelerators, by direct detection of scattering
in terrestrial detectors, and indirect detection of products from dark matter
particle annihilation in the galactic halo, are discussed and their
complementarity is explained. Direct detection experiments have revealed some
possible indications of a dark matter signal, but the situation is quite
confusing at the moment. Very recently, also indirect detection has entered a
sensitivity region where some particle candidates could be detectable. Indeed,
also here there are some (presently non-conclusive) indications of possible
dark matter signals, like an interesting structure at 130 GeV gamma-ray energy
found in publicly available data from the Fermi-LAT space detector. The future
of the field will depend on whether WIMPs are indeed the dark matter, something
that may realistically be probed in the next few years. If this exciting
scenario turns out to be true, we can expect a host of other, complementary
experiments in the coming decade. If it is not true, the time scale and methods
for detection will be much more uncertain.Comment: To be published in Annalen der Physik special issue DARK MATTER
edited by M. Bartelmann and V. Springel; Ann.Phys. (Berlin) 524, (2012
- …