441 research outputs found

    Dizziness, but not falls rate, improves after routine cataract surgery: the role of refractive and spectacle changes

    Get PDF
    YesPurpose To determine whether dizziness and falls rates change due to routine cataract surgery and to determine the influence of spectacle type and refractive factors. Methods Self-reported dizziness and falls were determined in 287 patients (mean age of 76.5 ± 6.3 years, 55% females) before and after routine cataract surgery for the first (81, 28%), second (109, 38%) and both eyes (97, 34%). Dizziness was determined using the short-form of the Dizziness Handicap Inventory. Six-month falls rates were determined using self-reported retrospective data. Results The number of patients with dizziness reduced significantly after cataract surgery (52% vs 38%; χ2 = 19.14, p < 0.001), but the reduction in the number of patients who fell in the 6-months post surgery was not significant (23% vs 20%; χ2 = 0.87, p = 0.35). Dizziness improved after first eye surgery (49% vs 33%, p = 0.01) and surgery on both eyes (58% vs 35%, p < 0.001), but not after second eye surgery (52% vs 45%, p = 0.68). Multivariate logistic regression analyses found significant links between post-operative falls and change in spectacle type (increased risk if switched into multifocal spectacles). Post-operative dizziness was associated with changes in best eye visual acuity and changes in oblique astigmatic correction. Conclusions Dizziness is significantly reduced by first (or both) eye cataract surgery and this is linked with improvements in best eye visual acuity, although changes in oblique astigmatic correction increased dizziness. The lack of improvement in falls rate may be associated with switching into multifocal spectacle wear after surgery.This work was supported by The Dunhill Medical Trust(grant number SA14/0711)

    Phosphorylation-dependent substrate selectivity of protein kinase B (AKT1)

    Get PDF
    Protein kinase B (AKT1) is a central node in a signaling pathway that regulates cell survival. The diverse pathways regulated by AKT1 are communicated in the cell via the phosphorylation of perhaps more than 100 cellular substrates. AKT1 is itself activated by phosphorylation at Thr-308 and Ser-473. Despite the fact that these phosphorylation sites are biomarkers for cancers and tumor biology, their individual roles in shaping AKT1 substrate selectivity are unknown. We recently developed a method to produce AKT1 with programmed phosphorylation at either or both of its key regulatory sites. Here, we used both defined and randomized peptide libraries to map the substrate selectivity of site-specific, singly and doubly phosphorylated AKT1 variants. To globally quantitate AKT1 substrate preferences, we synthesized three AKT1 substrate peptide libraries: one based on 84 “known” substrates and two independent and larger oriented peptide array libraries (OPALs) of ~1011 peptides each. We found that each phospho-form of AKT1 has common and distinct substrate requirements. Compared with pAKT1T308, the addition of Ser-473 phosphorylation increased AKT1 activities on some, but not all of its substrates. This is the first report that Ser-473 phosphorylation can positively or negatively regulate kinase activity in a substrate-dependent fashion. Bioinformatics analysis indicated that the OPAL-activity data effectively discriminate known AKT1 substrates from closely related kinase substrates. Our results also enabled predictions of novel AKT1 substrates that suggest new and expanded roles for AKT1 signaling in regulating cellular processes

    Differential uptake, kinetics and mechanisms of intracellular trafficking of next-generation antisense oligonucleotides across human cancer cell lines.

    Get PDF
    Antisense oligonucleotides (ASOs) modulate cellular target gene expression through direct binding to complementary RNA. Advances in ASO chemistry have led to the development of phosphorothioate (PS) ASOs with constrained-ethyl modifications (cEt). These next-generation cEt-ASOs can enter cells without transfection reagents. Factors involved in intracellular uptake and trafficking of cEt-ASOs leading to successful target knockdown are highly complex and not yet fully understood. AZD4785 is a potent and selective therapeutic KRAS cEt-ASO currently under clinical development for the treatment of cancer. Therefore, we used this to investigate mechanisms of cEt-ASO trafficking across a panel of cancer cells. We found that the extent of ASO-mediated KRAS mRNA knockdown varied significantly between cells and that this did not correlate with bulk levels of intracellular accumulation. We showed that in cells with good productive uptake, distribution of ASO was perinuclear and in those with poor productive uptake distribution was peripheral. Furthermore, ASO rapidly trafficked to the late endosome/lysosome in poor productive uptake cells compared to those with more robust knockdown. An siRNA screen identified several factors mechanistically involved in productive ASO uptake, including the endosomal GTPase Rab5C. This work provides novel insights into the trafficking of cEt-ASOs and mechanisms that may determine their cellular fate

    Feasibility and design of a trial regarding the optimal mode of delivery for preterm birth: the CASSAVA multiple methods study

    Get PDF
    BACKGROUND: Around 60,000 babies are born preterm (prior to 37 weeks' gestation) each year in the UK. There is little evidence on the optimal birth mode (vaginal or caesarean section). OBJECTIVE: The overall aim of the CASSAVA project was to determine if a trial to define the optimal mode of preterm birth could be carried out and, if so, determine what sort of trial could be conducted and how it could best be performed. We aimed to determine the specific groups of preterm women and babies for whom there are uncertainties about the best planned mode of birth, and if there would be willingness to recruit to, and participate in, a randomised trial to address some, but not all, of these uncertainties. This project was conducted in response to a Heath Technology Assessment programme commissioning call (17/22 'Mode of delivery for preterm infants'). METHODS: We conducted clinician and patient surveys (n = 224 and n = 379, respectively) to identify current practice and opinion, and a consensus survey and Delphi workshop (n = 76 and n = 22 participants, respectively) to inform the design of a hypothetical clinical trial. The protocol for this clinical trial/vignette was used in telephone interviews with clinicians (n = 24) and in focus groups with potential participants (n = 13). RESULTS: Planned sample size and data saturation was achieved for all groups except for focus groups with participants, as this had to be curtailed because of the COVID-19 pandemic and data saturation was not achieved. There was broad agreement from parents and health-care professionals that a trial is needed. The clinician survey demonstrated a variety of practice and opinion. The parent survey suggested that women and their families generally preferred vaginal birth at later gestations and caesarean section for preterm infants. The interactive workshop and Delphi consensus process confirmed the need for more evidence (hence the case for a trial) and provided rich information on what a future trial should entail. It was agreed that any trial should address the areas with most uncertainty, including the management of women at 26-32 weeks' gestation, with either spontaneous preterm labour (cephalic presentation) or where preterm birth was medically indicated. Clear themes around the challenges inherent in conducting any trial emerged, including the concept of equipoise itself. Specific issues were as follows: different clinicians and participants would be in equipoise for each clinical scenario, effective conduct of the trial would require appropriate resources and expertise within the hospital conducting the trial, potential participants would welcome information on the trial well before the onset of labour and minority ethnic groups would require tailored approaches. CONCLUSION: Given the lack of evidence and the variation of practice and opinion in this area, and having listened to clinicians and potential participants, we conclude that a trial should be conducted and the outlined challenges resolved. FUTURE WORK: The CASSAVA project could be used to inform the design of a randomised trial and indicates how such a trial could be carried out. Any future trial would benefit from a pilot with qualitative input and a study within a trial to inform optimal recruitment. LIMITATIONS: Certainty that a trial could be conducted can be determined only when it is attempted. TRIAL REGISTRATION: Current Controlled Trials ISRCTN12295730. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 61. See the NIHR Journals Library website for further project information

    Snow algae communities in Antarctica: metabolic and taxonomic composition.

    Get PDF
    Snow algae are found in snowfields across cold regions of the planet, forming highly visible red and green patches below and on the snow surface. In Antarctica, they contribute significantly to terrestrial net primary productivity due to the paucity of land plants, but our knowledge of these communities is limited. Here we provide the first description of the metabolic and species diversity of green and red snow algae communities from four locations in Ryder Bay (Adelaide Island, 68°S), Antarctic Peninsula. During the 2015 austral summer season, we collected samples to measure the metabolic composition of snow algae communities and determined the species composition of these communities using metabarcoding. Green communities were protein-rich, had a high chlorophyll content and contained many metabolites associated with nitrogen and amino acid metabolism. Red communities had a higher carotenoid content and contained more metabolites associated with carbohydrate and fatty acid metabolism. Chloromonas, Chlamydomonas and Chlorella were found in green blooms but only Chloromonas was detected in red blooms. Both communities also contained bacteria, protists and fungi. These data show the complexity and variation within snow algae communities in Antarctica and provide initial insights into the contribution they make to ecosystem functioning.European Union (project no. 215G) INTERREG IVB ‘Energetic Algae’ (EnAlgae) program and a Leverhulme Trust Research Grant (RPG-2017-077

    Feasibility and design of a trial regarding the optimal mode of delivery for preterm birth:the CASSAVA multiple methods study

    Get PDF
    Background: Around 60,000 babies are born preterm (prior to 37 weeks’ gestation) each year in the UK. There is little evidence on the optimal birth mode (vaginal or caesarean section). Objective: The overall aim of the CASSAVA project was to determine if a trial to define the optimal mode of preterm birth could be carried out and, if so, determine what sort of trial could be conducted and how it could best be performed. We aimed to determine the specific groups of preterm women and babies for whom there are uncertainties about the best planned mode of birth, and if there would be willingness to recruit to, and participate in, a randomised trial to address some, but not all, of these uncertainties. This project was conducted in response to a Heath Technology Assessment programme commissioning call (17/22 ‘Mode of delivery for preterm infants’). Methods: We conducted clinician and patient surveys (n = 224 and n = 379, respectively) to identify current practice and opinion, and a consensus survey and Delphi workshop (n = 76 and n = 22 participants, respectively) to inform the design of a hypothetical clinical trial. The protocol for this clinical trial/vignette was used in telephone interviews with clinicians (n = 24) and in focus groups with potential participants (n = 13). Results: Planned sample size and data saturation was achieved for all groups except for focus groups with participants, as this had to be curtailed because of the COVID-19 pandemic and data saturation was not achieved. There was broad agreement from parents and health-care professionals that a trial is needed. The clinician survey demonstrated a variety of practice and opinion. The parent survey suggested that women and their families generally preferred vaginal birth at later gestations and caesarean section for preterm infants. The interactive workshop and Delphi consensus process confirmed the need for more evidence (hence the case for a trial) and provided rich information on what a future trial should entail. It was agreed that any trial should address the areas with most uncertainty, including the management of women at 26–32 weeks’ gestation, with either spontaneous preterm labour (cephalic presentation) or where preterm birth was medically indicated. Clear themes around the challenges inherent in conducting any trial emerged, including the concept of equipoise itself. Specific issues were as follows: different clinicians and participants would be in equipoise for each clinical scenario, effective conduct of the trial would require appropriate resources and expertise within the hospital conducting the trial, potential participants would welcome information on the trial well before the onset of labour and minority ethnic groups would require tailored approaches. Conclusion: Given the lack of evidence and the variation of practice and opinion in this area, and having listened to clinicians and potential participants, we conclude that a trial should be conducted and the outlined challenges resolved. Future work: The CASSAVA project could be used to inform the design of a randomised trial and indicates how such a trial could be carried out. Any future trial would benefit from a pilot with qualitative input and a study within a trial to inform optimal recruitment. Limitations: Certainty that a trial could be conducted can be determined only when it is attempted. Trial registration: Current Controlled Trials ISRCTN12295730. Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 61. See the NIHR Journals Library website for further project information

    MobiDB: Intrinsically disordered proteins in 2021

    Get PDF
    The MobiDB database (URL: https://mobidb.org/) provides predictions and annotations for intrinsically disordered proteins. Here, we report recent developments implemented in MobiDB version 4, regarding the database format, with novel types of annotations and an improved update process. The new website includes a re-designed user interface, a more effective search engine and advanced API for programmatic access. The new database schema gives more flexibility for the users, as well as simplifying the maintenance and updates. In addition, the new entry page provides more visualisation tools including customizable feature viewer and graphs of the residue contact maps. MobiDB v4 annotates the binding modes of disordered proteins, whether they undergo disorder-to-order transitions or remain disordered in the bound state. In addition, disordered regions undergoing liquid-liquid phase separation or post-translational modifications are defined. The integrated information is presented in a simplified interface, which enables faster searches and allows large customized datasets to be downloaded in TSV, Fasta or JSON formats. An alternative advanced interface allows users to drill deeper into features of interest. A new statistics page provides information at database and proteome levels. The new MobiDB version presents state-of-the-art knowledge on disordered proteins and improves data accessibility for both computational and experimental users.Fil: Piovesan, Damiano. UniversitĂ  di Padova; ItaliaFil: Necci, Marco. UniversitĂ  di Padova; ItaliaFil: Escobedo, Nahuel Abel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂ­a; ArgentinaFil: Monzon, Alexander Miguel. UniversitĂ  di Padova; ItaliaFil: VicziĂĄn, AndrĂĄs. UniversitĂ  di Padova; ItaliaFil: Mičetić, Ivan. UniversitĂ  di Padova; ItaliaFil: Quaglia, Federica. UniversitĂ  di Padova; ItaliaFil: Paladin, Lisanna. UniversitĂ  di Padova; ItaliaFil: Ramasamy, Pathmanaban. Vrije Unviversiteit Brussel; BĂ©lgica. University of Ghent; BĂ©lgica. Interuniversity Institute of Bioinformatics in Brussels; BĂ©lgicaFil: DosztĂĄnyi, Zsuzsanna. Eötvös LorĂĄnd University; HungrĂ­aFil: Vranken, Wim F.. Vrije Unviversiteit Brussel; BĂ©lgica. Interuniversity Institute of Bioinformatics in Brussels; BĂ©lgicaFil: Davey, Norman E.. The Institute Of Cancer Research; Reino UnidoFil: Parisi, Gustavo Daniel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂ­a; ArgentinaFil: Fuxreiter, Monika. UniversitĂ  di Padova; ItaliaFil: Tosatto, Silvio C. E.. UniversitĂ  di Padova; Itali

    MobiDB 3.0: More annotations for intrinsic disorder, conformational diversity and interactions in proteins

    Get PDF
    The MobiDB (URL: mobidb.bio.unipd.it) database of protein disorder and mobility annotations has been significantly updated and upgraded since its last major renewal in 2014. Several curated datasets for intrinsic disorder and folding upon binding have been integrated from specialized databases. The indirect evidence has also been expanded to better capture information available in the PDB, such as high temperature residues in X-ray structures and overall conformational diversity. Novel nuclear magnetic resonance chemical shift data provides an additional experimental information layer on conformational dynamics. Predictions have been expanded to provide new types of annotation on backbone rigidity, secondary structure preference and disordered binding regions. MobiDB 3.0 contains information for the complete UniProt protein set and synchronization has been improved by covering all UniParc sequences. An advanced search function allows the creation of a wide array of custom-made datasets for download and further analysis. A large amount of information and cross-links to more specialized databases are intended to make MobiDB the central resource for the scientific community working on protein intrinsic disorder and mobility.Fil: Piovesan, Damiano. UniversitĂ  di Padova; ItaliaFil: Tabaro, Francesco. UniversitĂ  di Padova; ItaliaFil: Paladin, Lisanna. UniversitĂ  di Padova; ItaliaFil: Necci, Marco. UniversitĂ  di Padova; Italia. Instituto Agrario San Michele all'Adige Fondazione Edmund Mach; ItaliaFil: Micetić, Ivan. UniversitĂ  di Padova; ItaliaFil: Camilloni, Carlo. UniversitĂ  degli Studi di Milano; ItaliaFil: Davey, Norman. Universidad de Dublin; IrlandaFil: DosztĂĄnyi, Zsuzsanna. Eötvös LorĂĄnd University; HungrĂ­aFil: MĂ©szĂĄros, BĂĄlint. Eötvös LorĂĄnd University; HungrĂ­aFil: MonzĂłn, Alexander. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂ­a; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Parisi, Gustavo Daniel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y TecnologĂ­a; ArgentinaFil: Schad, Eva. Hungarian Academy Of Sciences; HungrĂ­aFil: Sormanni, Pietro. University of Cambridge; Reino UnidoFil: Tompa, Peter. Vrije Unviversiteit Brussel; BĂ©lgicaFil: Vendruscolo, Michele. University of Cambridge; Reino UnidoFil: Vranken, Wim F.. Vrije Unviversiteit Brussel; BĂ©lgicaFil: Tosatto, Silvio C. E.. UniversitĂ  di Padova; Itali
    • 

    corecore