169 research outputs found
A Role for Calcium Influx in the Regulation of Mitochondrial Calcium in Endothelial Cells
By using an endothelial cell line (ECV304), derived from human umbilical vein and transfected with recombinant aequorin targeted to the mitochondrial matrix, we find that stimulation with ATP evokes long lasting increases in mitochondrial Ca2+ ([Ca2+]m) that largely depend on Ca2+ influx. In these cells, the release of stored Ca2+ is inefficient at elevating [Ca2+]m. Consequently it appears that in ECV304 cells, bulk cytosolic Ca2+ ([Ca2+]c) is the main determinant of [Ca2+]m changes. In ECV304 cells4% of mitochondria are within 700 nm of the endoplasmic reticulum as opposed to 65% in HeLa cells, whereas 14% are within 700 nm of the inner surface of the plasma membrane, compared with6% in HeLa cells. Following Ca2+ depletion, readdition of extracellular Ca2+ evokes an increase in [Ca2+]m but not in [Ca2+]c. Under these conditions, microdomains of high [Ca2+]c may occur beneath the plasma membrane of ECV304 cells resulting in the preferential elevation of Ca2+ in mitochondria located in this region. A model is discussed in which the localization of mitochondria with respect to Ca2+ sources is the main determinant of their in situ Ca2+ uptake kinetics. Thus, in any given cell type mitochondria may be localized to suit the energy and metabolic demands of their physiological actions
From theory to practice : a roadmap for applying dual-process theory in design cognition research
Dual-process theory categorises cognition into two types of processing: Type 1 which is intuitive, autonomous processing, and Type 2 which is reflective processing that burdens limited executive cognitive resources (i.e. working memory). A recent call for increased theory-driven research in the field of design has led to a framing of dual-process theory as a foundation for design research. This research note presents a roadmap for future dual-process theory-driven design research outlining three main stages: defining dual-process theory constructs, determining research focus, and selecting research methods. Across these stages, we offer a conceptualisation of dual-process theory for design researchers, outlining the main concepts of the theory. We then present how a research study design must consider the nature of design problems (complex, ill-structured, ambiguous), designers, and the practice of design. Finally, we outline the main methods employed in dual-process theory research: behavioural, physiological, and self-report measures, suggesting ways to adapt such methods to design contexts. Ultimately, this work presents how dual-process theory may connect with theories of cognition often considered in design and offers a path forward for dual-process theory-driven design research
Lessons from the first clinical trial of a non-licensed vaccine among Ugandan adolescents: a phase II field trial of the tuberculosis candidate vaccine, MVA85A
Background: A more effective vaccine for tuberculosis (TB) is a global public health priority. Vaccines under development will always need evaluation in endemic settings, most of which have limited resources. Adolescents are an important target population for a new TB vaccine and for other vaccines which are relevant at school-age. However, in most endemic settings there is limited experience of trials of investigational products among adolescents, and adolescents are not routinely vaccinated. Methods: We used Modified vaccinia Ankara-expressing Ag85A (MVA85A), a well-tolerated candidate vaccine for tuberculosis, to assess the effect of Schistosoma mansoni infection on vaccine immunogenicity among Ugandan adolescents in primary school. We describe here the challenges and lessons learned in designing and implementing this first clinical trial among Ugandan adolescents using a non-licensed vaccine. Results: The school based immunization study was feasible and adhered to Good Clinical Practice principles. Engagement with the community and all stakeholders was critical for successful implementation of the trial. Creative and adaptable strategies were used to address protocol-specific, operational and logistical challenges. This study provided lessons and solutions that can be applied to other trials among adolescents in similar settings elsewhere, and to school-based immunization programs. Conclusion: Sufficient time and resources should be planned for community preparation and sensitization to ensure buy in and acceptance of a project of this kind. This trial shows that challenges to implementing early field trials in Africa are not insurmountable and that necessary well-planned high-quality ethical trials are feasible and should be encouraged. Trial Registration: ClinicalTrials.gov NCT02178748 03/06/201
Automated Classification of Depression from Structural Brain Measures across Two Independent Community-based Cohorts
ACKNOWLEDGEMENTS: This study was supported and funded by the Wellcome Trust Strategic Award âStratifying Resilience and Depression Longitudinallyâ (STRADL) (Reference 104036/Z/14/Z), and the Medical Research Council Mental Health Pathfinder Award âLeveraging routinely collected and linked research data to study the causes and consequences of common mental disordersâ (Reference MRC-MC_PC_17209). MAH is supported by research funding from the Dr Mortimer and Theresa Sackler Foundation. The research was conducted using the UK Biobank resource, with application number 4844. Structural brain imaging data from the UK Biobank was processed at the University of Edinburgh Centre for Cognitive Ageing and Cognitive Epidemiology (CCACE) http://www.ccace.ed.ac.uk/), which is a part of the crosscouncil Lifelong Health and Wellbeing Initiative (MR/K026992/1). CCACE received funding from Biotechnology and Biological Sciences Research Council (BBSRC), Medical Research Council (MRC), and was also supported by Age UK as part of The Disconnected Mind project. This work has made use of the resources provided by the Edinburgh Compute and Data Facility (ECDF) (http://www.ecdf.ed.ac.uk/)Peer reviewedPublisher PD
Disrupted limbic-prefrontal effective connectivity in response to fearful faces in lifetime depression
Background: Multiple brain imaging studies of negative emotional bias in major depressive disorder (MDD) have used images of fearful facial expressions and focused on the amygdala and the prefrontal cortex. The results have, however, been inconsistent, potentially due to small sample sizes (typically N < 50 ). It remains unclear if any alterations are a characteristic of current depression or of past experience of depression, and whether there are MDD-related changes in effective connectivity between the two brain regions.Methods: Activations and effective connectivity between the amygdala and dorsolateral prefrontal cortex (DLPFC) in response to fearful face stimuli were studied in a large population-based sample from Generation Scotland. Participants either had no history of MDD ( N = 664 in activation analyses, N = 474 in connectivity analyses) or had a diagnosis of MDD during their lifetime (LMDD, N = 290 in activation analyses, N = 214 in connectivity analyses). The within-scanner task involved implicit facial emotion processing of neutral and fearful faces.Results: Compared to controls, LMDD was associated with increased activations in left amygdala ( PFWE = 0.031 , k E = 4 ) and left DLPFC ( PFWE = 0.002 , k E = 33 ), increased mean bilateral amygdala activation ( ÎČ = 0.0715, P = 0.0314 ), and increased inhibition from left amygdala to left DLPFC, all in response to fearful faces contrasted to baseline. Results did not appear to be attributable to depressive illness severity or antidepressant medication status at scan time.Limitations: Most studied participants had past rather than current depression, average severity of ongoing depression symptoms was low, and a substantial proportion of participants were receiving medication. The study was not longitudinal and the participants were only assessed a single time.Conclusions: LMDD is associated with hyperactivity of the amygdala and DLPFC, and with stronger amygdala to DLPFC inhibitory connectivity, all in response to fearful faces, unrelated to depression severity at scan time. These results help reduce inconsistency in past literature and suggest disruption of âbottom-upâ limbic-prefrontal effective connectivity in depression
Safety and immunogenicity of an FP9-vectored candidate tuberculosis vaccine (FP85A), alone and with candidate vaccine MVA85A in BCG-vaccinated healthy adults: a phase I clinical trial.
The safety and immunogenicity of a new candidate tuberculosis (TB) vaccine, FP85A was evaluated alone and in heterologous prime-boost regimes with another candidate TB vaccine, MVA85A. This was an open label, non-controlled, non-randomized Phase I clinical trial. Healthy previously BCG-vaccinated adult subjects were enrolled sequentially into three groups and vaccinated with FP85A alone, or both FP85A and MVA85A, with a four week interval between vaccinations. Passive and active data on adverse events were collected. Immunogenicity was evaluated by Enzyme Linked Immunospot (ELISpot), flow cytometry and Enzyme Linked Immunosorbent assay (ELISA). Most adverse events were mild and there were no vaccine-related serious adverse events. FP85A vaccination did not enhance antigen 85A-specific cellular immunity. When MVA85A vaccination was preceded by FP85A vaccination, cellular immune responses were lower compared with when MVA85A vaccination was the first immunisation. MVA85A vaccination, but not FP85A vaccination, induced anti-MVA IgG antibodies. Both MVA85A and FP85A vaccinations induced anti-FP9 IgG antibodies. In conclusion, FP85A vaccination was well tolerated but did not induce antigen-specific cellular immune responses. We hypothesize that FP85A induced anti-FP9 IgG antibodies with cross-reactivity for MVA85A, which may have mediated inhibition of the immune response to subsequent MVA85A. ClinicalTrials.gov identification number: NCT00653770
Structural brain correlates of childhood trauma with replication across two large, independent community-based samples
Blunted Medial Prefrontal Cortico-Limbic Reward-Related Effective Connectivity and Depression
Stratifying Resilience and Depression Longitudinally (STRADL) was supported by the Wellcome Trust through a Strategic Award (Grant No. 104036/Z/14/Z). Parts of the work were supported by a China Scholarship Council (Grant No. 201506040037 to SX), National Institutes of Health (Grant No. DA027764 to MRD), Lister Institute Prize Fellowship 2016â2021 (to DJS), Dr Mortimer and Theresa Sackler Foundation (AMM, HCW, and SML), Centre for Cognitive Ageing and Cognitive Epidemiology (IJD and AMM), Medical Research Council and Biotechnology and Biological Sciences Research Council (Grant No. MR/K026992/1), Royal College of Physicians of Edinburgh John, Margaret, Alfred and Stewart Sim fellowship (to HCW), and University of Edinburgh, Edinburgh Scientific Academic TmPCk College Fellowship (to HCW). The Chief Scientist Office of the Scottish Government Health Department (Grant No. CZD/16/6) and Scottish Funding Council (Grant No. HR03006) provided core support for Generation Scotland. Data acquisition was additionally supported by the Scottish Mental Health Research Network and Scottish Governmentâs Support for Science initiative. LR, HCW, and AMM, received financial support from Pfizer (formerly Wyeth) in relation to imaging studies of people with schizophrenia and bipolar disorder. AMM has previously received grant support from Lilly and Janssen. SML has received honoraria for lectures, chairing meetings, and consultancy work from Janssen in connection with brain imaging and therapeutic initiatives for psychosis. JDS has received funding via an honorarium associated with a lecture or Wyeth and funding from Indivior for a study on opioid dependency. No other disclosures were reported. The authors declare no conflict of interest.Peer reviewedPublisher PD
A single dose of ChAdOx1 Chik vaccine induces neutralising antibodies against four chikungunya virus lineages in a phase 1 clinical trial
Chikungunya virus (CHIKV) is a reemerging mosquito-borne virus that causes swift outbreaks. Major concerns are the persistent and disabling polyarthralgia in infected individuals. Here we present the results from a first-in-human trial of the candidate simian adenovirus vectored vaccine ChAdOx1 Chik, expressing the CHIKV full-length structural polyprotein (Capsid, E3, E2, 6k and E1). 24 adult healthy volunteers aged 18â50 years, were recruited in a dose escalation, open-label, nonrandomized and uncontrolled phase 1 trial (registry NCT03590392). Participants received a single intramuscular injection of ChAdOx1 Chik at one of the three preestablished dosages and were followed-up for 6 months. The primary objective was to assess safety and tolerability of ChAdOx1 Chik. The secondary objective was to assess the humoral and cellular immunogenicity. ChAdOx1 Chik was safe at all doses tested with no serious adverse reactions reported. The vast majority of solicited adverse events were mild or moderate, and self-limiting in nature. A single dose induced IgG and Tcell responses against the CHIKV structural antigens. Broadly neutralizing antibodies against the four CHIKV lineages were found in all participants and as early as 2 weeks after vaccination. In summary, ChAdOx1 Chik showed excellent safety, tolerability and 100% PRNT50 seroconversion after a single dose
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