24 research outputs found

    Angiographic and pathologic features of probable primary carcinoid-like hepatic tumors

    Full text link
    The angiographic and pathologic features of two cases of primary carcinoid-like hepatic tumors are described. Neither patient had the carcinoid syndrome.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48148/1/261_2005_Article_BF01887101.pd

    Neurobiological basis and risk factors of persistent fatigue and concentration problems after COVID-19: study protocol for a prospective case–control study (VeCosCO)

    Get PDF
    Introduction: The risk factors for persistent fatigue and cognitive complaints after infection with SARS-CoV-2 and the underlying pathophysiology are largely unknown. Both clinical factors and cognitive-behavioural factors have been suggested to play a role in the perpetuation of complaints. A neurobiological aetiology, such as neuroinflammation, could be the underlying pathophysiological mechanism for persisting complaints. To unravel factors associated with persisting complaints, VeCosCO will compare individuals with and without persistent fatigue and cognitive complaints >3 months after infection with SARS-CoV-2. The study consists of two work packages. The first work package aims to (1) investigate the relation between persisting complaints and neuropsychological functioning; (2) determine risk factors and at-risk phenotypes for the development of persistent fatigue and cognitive complaints, including the presence of postexertional malaise and (3) describe consequences of persistent complaints on quality of life, healthcare consumption and physical functioning. The second work package aims to (1) determine the presence of neuroinflammation with [18F]DPA-714 whole-body positron emission tomography (PET) scans in patients with persisting complaints and (2) explore the relationship between (neuro)inflammation and brain structure and functioning measured with MRI. / Methods and analysis: This is a prospective case–control study in participants with and without persistent fatigue and cognitive complaints, >3 months after laboratory-confirmed SARS-CoV-2 infection. Participants will be mainly included from existing COVID-19 cohorts in the Netherlands covering the full spectrum of COVID-19 acute disease severity. Primary outcomes are neuropsychological functioning, postexertional malaise, neuroinflammation measured using [18F]DPA-714 PET, and brain functioning and structure using (f)MRI. / Ethics and dissemination: Work package 1 (NL79575.018.21) and 2 (NL77033.029.21) were approved by the medical ethical review board of the Amsterdam University Medical Centers (The Netherlands). Informed consent is required prior to participation in the study. Results of this study will be submitted for publication in peer-reviewed journals and shared with the key population

    Fluid flow in the osteocyte mechanical environment : a fluid-structure interaction approach

    Get PDF
    Osteocytes are believed to be the primary sensor of mechanical stimuli in bone, which orchestrate osteoblasts and osteoclasts to adapt bone structure and composition to meet physiological loading demands. Experimental studies to quantify the mechanical environment surrounding bone cells are challenging, and as such, computational and theoretical approaches have modelled either the solid or fluid environment of osteocytes to predict how these cells are stimulated in vivo. Osteocytes are an elastic cellular structure that deforms in response to the external fluid flow imposed by mechanical loading. This represents a most challenging multi-physics problem in which fluid and solid domains interact, and as such, no previous study has accounted for this complex behaviour. The objective of this study is to employ fluid–structure interaction (FSI) modelling to investigate the complex mechanical environment of osteocytes in vivo. Fluorescent staining of osteocytes was performed in order to visualise their native environment and develop geometrically accurate models of the osteocyte in vivo. By simulating loading levels representative of vigorous physiological activity (3,000με compression and 300 Pa pressure gradient), we predict average interstitial fluid velocities (∼60.5μ m/s ) and average maximum shear stresses (∼11 Pa ) surrounding osteocytes in vivo. Interestingly, these values occur in the canaliculi around the osteocyte cell processes and are within the range of stimuli known to stimulate osteogenic responses by osteoblastic cells in vitro. Significantly our results suggest that the greatest mechanical stimulation of the osteocyte occurs in the cell processes, which, cell culture studies have indicated, is the most mechanosensitive area of the cell. These are the first computational FSI models to simulate the complex multi-physics mechanical environment of osteocyte in vivo and provide a deeper understanding of bone mechanobiology

    Psychosocial Factors Associated with Subclinical Atherosclerosis in South Asians: The MASALA Study

    Full text link
    South Asians have the highest rates of premature atherosclerotic cardiovascular disease (ASCVD) amongst all ethnic groups in the world; however this risk cannot be fully explained by traditional risk factors. Participants from the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study were included in this cross-sectional analysis. The purpose of this study was to investigate the association of psychosocial factors (including anger, anxiety, depressive symptoms, current and chronic stress, social support, and everyday hassles) with carotid intima-media thickness (CIMT). Three multivariate models were examined to evaluate the association between the psychosocial factors and cIMT. Findings suggest that the impact of psychosocial factors on subclinical atherosclerosis is differential for South Asian men and women. For men, anxiety and depression were associated; while for women, stress was associated with common carotid intima media thickness, independent of traditional CVD risk factors, diet and physical activity

    N-Glycosylation of the Na+-Taurocholate Cotransporting Polypeptide (NTCP) Determines Its Trafficking and Stability and Is Required for Hepatitis B Virus Infection.

    No full text
    The sodium/bile acid cotransporter NTCP was recently identified as a receptor for hepatitis B virus (HBV). NTCP is glycosylated and the role of glycans in protein trafficking or viral receptor activity is not known. NTCP contains two N-linked glycosylation sites and asparagine amino acid residues N5 and N11 were mutated to a glutamine to generate NTCP with a single glycan (NTCP-N5Q or NTCP- N11Q) or no glycans (NTCP- N5,11Q). HepG2 cells expressing NTCP with a single glycan supported HBV infection at a comparable level to NTCP-WT. The physiological function of NTCP, the uptake of bile acids, was also not affected in cells expressing these single glycosylation variants, consistent with their trafficking to the plasma membrane. However, glycosylation-deficient NTCP (NTCP-N5,11Q) failed to support HBV infection, showed minimal cellular expression and was degraded in the lysosome. This affected the physiological bile acid transporter function of NTCP-N5,11Q in a similar fashion. In conclusion, N-glycosylation is required for efficient NTCP localization at the plasma membrane and subsequent HBV infection and these characteristics are preserved in NTCP carrying a single carbohydrate moiety

    Celebrating book culture: the aims and outcomes of UNESCOs World Book and Copyright Day in Europe

    No full text
    World Book and Copyright Day was established by a resolution of the 28th General Council of UNESCO in 1995. Its avowed aim was ‘to pay a world-wide tribute to books and authors on this date, encouraging everyone, and in particular young people, to discover the pleasure of reading and gain a renewed respect for the irreplaceable contributions of those who have furthered the social and cultural progress of humanity.’ This article examines the context for World Book and Copyright Day, the extent to which cultural and commercial interests have converged in the activities of the day and argues that an analysis of the activities of the day reveal a specifically European attitude to book culture
    corecore