Instituto Gulbenkian Ciencia

Oeiras, Portugal

Instituto Gulbenkian Ciencia

Oeiras, Portugal

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Holmes M.V.,University College London | Holmes M.V.,University of Pennsylvania | Dale C.E.,London School of Hygiene and Tropical Medicine | Zuccolo L.,University of Bristol | And 170 more authors.
BMJ (Online) | Year: 2014

Objective: To use the rs1229984 variant in the alcohol dehydrogenase 1B gene (ADH1B) as an instrument to investigate the causal role of alcohol in cardiovascular disease. Design: Mendelian randomisation meta-analysis of 56 epidemiological studies. Participants: 261 991 individuals of European descent, including 20 259 coronary heart disease cases and 10 164 stroke events. Data were available on ADH1B rs1229984 variant, alcohol phenotypes, and cardiovascular biomarkers. Main outcome measures: Odds ratio for coronary heart disease and stroke associated with the ADH1B variant in all individuals and by categories of alcohol consumption. Results: Carriers of the A-allele of ADH1B rs1229984 consumed 17.2% fewer units of alcohol per week (95% confidence interval 15.6% to 18.9%), had a lower prevalence of binge drinking (odds ratio 0.78 (95% CI 0.73 to 0.84)), and had higher abstention (odds ratio 1.27 (1.21 to 1.34)) than non-carriers. Rs1229984 A-allele carriers had lower systolic blood pressure (-0.88 (-1.19 to -0.56) mm Hg), interleukin-6 levels (-5.2% (-7.8 to -2.4%)), waist circumference (-0.3 (-0.6 to -0.1) cm), and body mass index (-0.17 (-0.24 to -0.10) kg/m2). Rs1229984 A-allele carriers had lower odds of coronary heart disease (odds ratio 0.90 (0.84 to 0.96)). The protective association of the ADH1B rs1229984 A-allele variant remained the same across all categories of alcohol consumption (P=0.83 for heterogeneity). Although no association of rs1229984 was identified with the combined subtypes of stroke, carriers of the A-allele had lower odds of ischaemic stroke (odds ratio 0.83 (0.72 to 0.95)). Conclusions: Individuals with a genetic variant associated with non-drinking and lower alcohol consumption had a more favourable cardiovascular profile and a reduced risk of coronary heart disease than those without the genetic variant. This suggests that reduction of alcohol consumption, even for light to moderate drinkers, is beneficial for cardiovascular health.

Mateus R.,Institute Medicina Molecular | Mateus R.,Instituto Gulbenkian Ciencia | Pereira T.,Institute Medicina Molecular | Pereira T.,Instituto Gulbenkian Ciencia | And 8 more authors.
PLoS ONE | Year: 2012

Background: Zebrafish (Danio rerio) has a remarkable capacity to regenerate many organs and tissues. During larval stages the fin fold allows the possibility of performing long time-lapse imaging making this system very appealing to study the relationships between tissue movements, cell migration and proliferation necessary for the regeneration process. Results: Through the combined use of transgenic fluorescently-labeled animals and confocal microscopy imaging, we characterized in vivo the complete fin fold regeneration process. We show, for the first time, that there is an increase in the global rate of epidermal growth as a response to tissue loss. Also enhanced significantly is cell proliferation, which upon amputation happens in a broad area concerning the amputation level and not in a blastema-restricted way. This reveals a striking difference with regard to the adult fin regeneration system. Finally, an accumulation of migratory, shape-changing fibroblasts occurs proximally to the wound area, resembling a blastemal-like structure, which may act as a signaling center for the regeneration process to proceed. Conclusions: These findings provide a novel in vivo description of fundamental mechanisms occurring during the fin fold regeneration process, thereby contributing to a better knowledge of this regenerative system and to reveal variations in the epimorphic regeneration field. © 2012 Mateus et al.

Pires A.E.,Instituto Gulbenkian Ciencia | Pires A.E.,Instituto Portugues Of Oncologia Of Lisbon | Afonso A.F.,Instituto Gulbenkian Ciencia | Afonso A.F.,Instituto Portugues Of Oncologia Of Lisbon | And 9 more authors.
Journal of Immunotherapy | Year: 2010

Natural antibodies are unique self molecules endowed with both suppressive and activating functions on various cells of the immune system and are recognized as a fundamental link between the adaptive and innate immune system. Here, we examine the role of natural antibodies, using polyclonal immunoglobulins (Ig), as a promoter of T-cell reconstitution in a context of lymphopenia. We have established a mouse model to mimic immunologic recovery in adult patients with severe hypothymic function subjected to autologous hematopoietic precursor cell transplantation. Thymectomized mice were transplanted and treated with low doses of Ig or its Fab or Fc fragments. The animals displayed, during early phases of Ig treatment, a significant increase of T-cell reconstitution displaying a naive CD4 +phenotype. In addition, the Igtreated animals exhibited an increase dilution of single-joint T-cell receptor excision circles (sjTRECs) in peripheral blood, suggesting an early increase in proliferation of T cells stimulated by the natural antibodies. These results unveil a novel and considerable effect of intravenous Ig treatment in situations of severe lymphopenia as a stimulator of proliferation of peripheral naive T cells, possibly protecting diverse immune repertoires. Copyright © 2010 by Lippincott Williams & Wilkins.

Mateus R.,New University of Lisbon | Lourenco R.,New University of Lisbon | Fang Y.,National Health Research Institute | Brito G.,University of Lisbon | And 5 more authors.
Development (Cambridge) | Year: 2015

Caudal fin regeneration is characterized by a proliferation boost in the mesenchymal blastema that is controlled precisely in time and space. This allows a gradual and robust restoration of original fin size. However, how this is established and regulated is not well understood. Here, we report that Yap, the Hippo pathway effector, is a chief player in this process: functionally manipulating Yap during regeneration dramatically affects cell proliferation and expression of key signaling pathways, impacting regenerative growth. The intracellular location of Yap is tightly associated with different cell densities along the blastema proximal-distal axis, which correlate with alterations in cell morphology, cytoskeleton and cell-cell contacts in a gradient-like manner. Importantly, Yap inactivation occurs in high cell density areas, conditional to F-actin distribution and polymerization. We propose that Yap is essential for fin regeneration and that its function is dependent on mechanical tension, conferred by a balancing act of cell density and cytoskeleton activity. © 2015. Published by The Company of Biologists Ltd.

Afonso A.B.,New University of Lisbon | Justo L.N.,New University of Lisbon | Queiros A.C.,New University of Lisbon | Fesel C.,Instituto Gulbenkian Ciencia | And 9 more authors.
Journal of Clinical Immunology | Year: 2013

Propose: After autologous stem cell transplantation (ASCT) the immunological B cell compartment recovers slowly. Delays on the recovery of B cell function after autologous stem cell transplantation are due to the low lymphocytes count and to their intrinsic dysfunction. Methods: We studied the in vivo B cell reconstitution after ASCT examining the independent effect of polyclonal IgG (PolyIg), Fab or Fc fragments infusions in a murine animal model during a period of 12 weeks. These molecules were used in low doses, mimicking the recommended use of IVIg in the case of hypogammaglobulinemia in humans. Flow cytometry analysis and ELISA tests were conducted to monitor the reconstitution of B cells and serum immunoglobulin production. Panama blot and PCA factor 1 analysis were used to study the kinetics of immunoglobulin repertoires reconstitution. Mechanistic studies were also performed using in vitro cell culture. Results: During follow-up after ASCT, peripheral B cells expand independently of treatment, correcting the immediate increase in sBAFF (soluble B cell activating factor) induced by previous intense myeloablation. Treatments with Fab and Fc fragments infusions promote significant IgM and IgG production comparing to control. Although the complete recovery of antibody repertoire is only achieved at the end of follow-up after ASCT, there is an earlier and significantly stronger recovery in the treated mice, which is evident at 9 weeks after ASCT. At 30 weeks after ASCT, normal values of antibody repertoire were detected in all individuals. Mechanistic studies show that Fab and Fc fragments promote IgG1 production by indirect pathways. Conclusions: The results presented here demonstrate that polyclonal immunoglobulin indirectly improves the function of the reconstituted B cells and their IgG production by means of Fc-mediated effects on bystander cells. These results further stimulate the discussion about the advantages of IVIg therapy during immune reconstitution after human ASCT.

PubMed | Francis Crick Institute, Eli Lilly and Company, University of Washington, New York University and 9 more.
Type: Journal Article | Journal: Cytometry. Part A : the journal of the International Society for Analytical Cytology | Year: 2016

The purpose of this document is to define minimal standards for a flow cytometry shared resource laboratory (SRL) and provide guidance for best practices in several important areas. This effort is driven by the desire of International Society for the Advancement of Cytometry (ISAC) members in SRLs to define and maintain standards of excellence in flow cytometry, and act as a repository for key elements of this information (e.g. example SOPs/training material, etc.). These best practices are not intended to define specifically how to implement these recommendations, but rather to establish minimal goals for an SRL to address in order to achieve excellence. It is hoped that once these best practices are established and implemented they will serve as a template from which similar practices can be defined for other types of SRLs. Identification of the need for best practices first occurred through discussions at the CYTO 2013 SRL Forum, with the most important areas for which best practices should be defined identified through several surveys and SRL track workshops as part of CYTO 2014. 2016 International Society for Advancement of Cytometry.

Campos C.,University of Geneva | Campos C.,Instituto Gulbenkian Ciencia | Kamiya M.,Ecole Polytechnique Federale de Lausanne | Banala S.,Ecole Polytechnique Federale de Lausanne | And 2 more authors.
Developmental Dynamics | Year: 2011

We present a method for the specific labelling of fusion proteins with synthetic fluorophores in Zebrafish. The method uses the SNAP-tag technology and O6-benzylguanine derivatives of various synthetic fluorophores. We demonstrate how the method can be used to label subcellular structures in Zebrafish such as the nucleus, cell membranes, and endosomal membranes. The stability of the synthetic fluorophores makes them attractive choices for long-term imaging and allows, unlike most of the autofluorescent proteins, the use of acid fixatives such as trichloroacetic acid. Furthermore, the use of O6-benzylguanine derivatives bearing caged fluorescein allows cell lineage tracing through photo-deprotection of the fluorophore and its detection either through fluorescence microscopy or through immunohistochemistry after fixation using anti-fluorescein antibodies. © 2011 Wiley-Liss, Inc.

Holt R.,University of Oxford | Sykes N.H.,University of Oxford | Conceicao I.C.,Instituto Nacional Of Saude Dr Ricardo Jorge | Conceicao I.C.,Instituto Gulbenkian Ciencia | And 12 more authors.
European Journal of Human Genetics | Year: 2012

There is strong evidence that rare copy number variants (CNVs) have a role in susceptibility to autism spectrum disorders (ASDs). Much research has focused on how CNVs mediate a phenotypic effect by altering gene expression levels. We investigated an alternative mechanism whereby CNVs combine the 5′ and 3′ ends of two genes, creating a fusion gene. Any resulting mRNA with an open reading frame could potentially alter the phenotype via a gain-of-function mechanism. We examined 2382 and 3096 rare CNVs from 996 individuals with ASD and 1287 controls, respectively, for potential to generate fusion transcripts. There was no increased burden in individuals with ASD; 122/996 cases harbored at least one rare CNV of this type, compared with 179/1287 controls (P<0.89). There was also no difference in the overall frequency distribution between cases and controls. We examined specific examples of such CNVs nominated by case-control analysis and a candidate approach. Accordingly, a duplication involving REEP1-POLR1A (found in 3/996 cases and 0/1287 controls) and a single occurrence CNV involving KIAA0319-TDP2 were tested. However, no fusion transcripts were detected by RT-PCR. Analysis of additional samples based on cell line availability resulted in validation of a MAPKAPK5-ACAD10 fusion transcript in two probands. However, this variant was present in controls at a similar rate and is unlikely to influence ASD susceptibility. In summary, although we find no evidence that fusion-gene generating CNVs lead to ASD susceptibility, discovery of a MAPKAPK5-ACAD10 transcript with an estimated frequency of 1/200 suggests that gain-of-function mechanisms should be considered in future CNVs studies. © 2012 Macmillan Publishers Limited. All rights reserved.

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