319 research outputs found

    The Eukaryotic Promoter Database (EPD): recent developments

    Get PDF
    The Eukaryotic Promoter Database (EPD) is an annotated non-redundant collection of eukaryotic POL II promoters, for which the transcription start site has been determined experimentally. Access to promoter sequences is provided by pointers to positions in nucleotide sequence entries. The annotation part of an entry includes description of the initiation site mapping data, cross-references to other databases, and bibliographic references. EPD is structured in a way that facilitates dynamic extraction of biologically meaningful promoter subsets for comparative sequence analysis. Recent efforts have focused on exhaustive cross-referencing to the EMBL nucleotide sequence database, and on the improvement of the WWW-based user interfaces and data retrieval mechanisms. EPD can be accessed at http://www.epd.isb-sib.c

    DYRK1A promotes dopaminergic neuron survival in the developing brain and in a mouse model of Parkinson's disease

    Get PDF
    In the brain, programmed cell death (PCD) serves to adjust the numbers of the different types of neurons during development, and its pathological reactivation in the adult leads to neurodegeneration. Dual-specificity tyrosine-(Y)-phosphorylation regulated kinase 1A (DYRK1A) is a pleiotropic kinase involved in neural proliferation and cell death, and its role during brain growth is evolutionarily conserved. Human DYRK1A lies in the Down syndrome critical region on chromosome 21, and heterozygous mutations in the gene cause microcephaly and neurological dysfunction. The mouse model for DYRK1A haploinsufficiency (the Dyrk1a +/− mouse) presents neuronal deficits in specific regions of the adult brain, including the substantia nigra (SN), although the mechanisms underlying these pathogenic effects remain unclear. Here we study the effect of DYRK1A copy number variation on dopaminergic cell homeostasis. We show that mesencephalic DA (mDA) neurons are generated in the embryo at normal rates in the Dyrk1a haploinsufficient model and in a model (the mBACtg Dyrk1a mouse) that carries three copies of Dyrk1a. We also show that the number of mDA cells diminishes in postnatal Dyrk1a +/− mice and increases in mBACtg Dyrk1a mice due to an abnormal activity of the mitochondrial caspase9 (Casp9)-dependent apoptotic pathway during the main wave of PCD that affects these neurons. In addition, we show that the cell death induced by 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP), a toxin that activates Casp9-dependent apoptosis in mDA neurons, is attenuated in adult mBACtg Dyrk1a mice, leading to an increased survival of SN DA neurons 21 days after MPTP intoxication. Finally, we present data indicating that Dyrk1a phosphorylation of Casp9 at the Thr125 residue is the mechanism by which this kinase hinders both physiological and pathological PCD in mDA neurons. These data provide new insight into the mechanisms that control cell death in brain DA neurons and they show that deregulation of developmental apoptosis may contribute to the phenotype of patients with imbalanced DYRK1A gene dosage

    Implantable cardioverter defibrillator therapy for primary prevention of sudden cardiac death in the real world: Main findings from the French multicentre DAI-PP programme (pilot phase)

    Get PDF
    This review summarizes the main findings of the French multicentre DAI-PP pilot programme, and discusses the related clinical and research perspectives. This project included retrospectively (2002–2012 period) more than 5000 subjects with structural heart disease who received an implantable cardioverter defibrillator (ICD) for primary prevention of sudden cardiac death, and were followed for a mean period of 3 years. The pilot phase of the DAI-PP programme has provided valuable information on several practical and clinically relevant aspects of primary prevention ICD implantation in the real-world population, which are summarized in this review. This pilot has led to a prospective evaluation that started in May 2018, assessing ICD therapy in primary and secondary prevention in patients with structural and electrical heart diseases, with remote monitoring follow-up using a dedicated platform. This should further enhance our understanding of sudden cardiac death, to eventually optimize the field of preventative actions

    Association of change in cardiovascular risk factors with incident cardiovascular events

    Get PDF
    Importance: There is consistent evidence of the association between ideal cardiovascular health and lower incident cardiovascular disease (CVD); however, most studies used a single measure of cardiovascular health.Objective: To examine how cardiovascular health changes over time and whether these changes are associated with incident CVD.Design, Setting, and Participants: Prospective cohort study in a UK general community (Whitehall II), with examinations of cardiovascular health from 1985/1988 (baseline) and every 5 years thereafter until 2015/2016 and follow-up for incident CVD until March 2017.Exposures: Using the 7 metrics of the American Heart Association (nonsmoking; and ideal levels of body mass index, physical activity, diet, blood pressure, fasting blood glucose, and total cholesterol), participants with 0 to 2, 3 to 4, and 5 to 7 ideal metrics were categorized as having low, moderate, and high cardiovascular health. Change in cardiovascular health over 10 years between 1985/1988 and 1997/1999 was considered.Main Outcome and Measure: Incident CVD (coronary heart disease and stroke).Results: The study population included 9256 participants without prior CVD (mean [SD] age at baseline, 44.8 [6.0] years; 2941 [32%] women), of whom 6326 had data about cardiovascular health change. Over a median follow-up of 18.9 years after 1997/1999, 1114 incident CVD events occurred. In multivariable analysis and compared with individuals with persistently low cardiovascular health (consistently low group, 13.5% of participants; CVD incident rate per 1000 person-years, 9.6 [95% CI, 8.4-10.9]), there was no significant association with CVD risk in the low to moderate group (6.8% of participants; absolute rate difference per 1000 person-years, -1.9 [95% CI, -3.9 to 0.1]; HR, 0.84 [95% CI, 0.66-1.08]), the low to high group, (0.3% of participants; absolute rate difference per 1000 person-years, -7.7 [95% CI, -11.5 to -3.9]; HR, 0.19 [95% CI, 0.03-1.35]), and the moderate to low group (18.0% of participants; absolute rate difference per 1000 person-years, -1.3 [95% CI, -3.0 to 0.3]; HR, 0.96 [95% CI, 0.80-1.15]). A lower CVD risk was observed in the consistently moderate group (38.9% of participants; absolute rate difference per 1000 person-years, -4.2 [95% CI, -5.5 to -2.8]; HR, 0.62 [95% CI, 0.53-0.74]), the moderate to high group (5.8% of participants; absolute rate difference per 1000 person-years, -6.4 [95% CI, -8.0 to -4.7]; HR, 0.39 [95% CI, 0.27-0.56]), the high to low group (1.9% of participants; absolute rate difference per 1000 person-years, -5.3 [95% CI, -7.8 to -2.8]; HR, 0.49 [95% CI, 0.29-0.83]), the high to moderate group (9.3% of participants; absolute rate difference per 1000 person-years, -4.5 [95% CI, -6.2 to -2.9]; HR, 0.66 [95% CI, 0.51-0.85]), and the consistently high group (5.5% of participants; absolute rate difference per 1000 person-years, -5.6 [95% CI, -7.4 to -3.9]; HR, 0.57 [95% CI, 0.40-0.80]).Conclusions and Relevance: Among a group of participants without CVD who received follow-up over a median 18.9 years, there was no consistent relationship between direction of change in category of a composite metric of cardiovascular health and risk of CVD

    14-3-3theta Protects against Neurotoxicity in a Cellular Parkinson's Disease Model through Inhibition of the Apoptotic Factor Bax

    Get PDF
    Disruption of 14-3-3 function by alpha-synuclein has been implicated in Parkinson's disease. As 14-3-3s are important regulators of cell death pathways, disruption of 14-3-3s could result in the release of pro-apoptotic factors, such as Bax. We have previously shown that overexpression of 14-3-3θ reduces cell loss in response to rotenone and MPP+ in dopaminergic cell culture and reduces cell loss in transgenic C. elegans that overexpress alpha-synuclein. In this study, we investigate the mechanism for 14-3-3θ's neuroprotection against rotenone toxicity. While 14-3-3s can inhibit many pro-apoptotic factors, we demonstrate that inhibition of one factor in particular, Bax, is important to 14-3-3s' protection against rotenone toxicity in dopaminergic cells. We found that 14-3-3θ overexpression reduced Bax activation and downstream signaling events, including cytochrome C release and caspase 3 activation. Pharmacological inhibition or shRNA knockdown of Bax provided protection against rotenone, comparable to 14-3-3θ's neuroprotective effects. A 14-3-3θ mutant incapable of binding Bax failed to protect against rotenone. These data suggest that 14-3-3θ's neuroprotective effects against rotenone are at least partially mediated by Bax inhibition and point to a potential therapeutic role of 14-3-3s in Parkinson's disease

    Readiness for smoking cessation in coronary heart disease patients across Europe: results from the EUROASPIRE III survey

    No full text
    Background: Readiness for smoking cessation is an important predictor of quit attempts and cessation success. We aimed to investigate the prevalence and correlates of readiness for smoking cessation in coronary heart disease (CHD) patients. Design: The EUROpean Action on Secondary and Primary Prevention by Intervention to Reduce Events III (EUROASPIRE III) survey is a cross-sectional study conducted in 2006–2007 among CHD patients <80 years of age from 22 European regions. Methods: Patients were interviewed on average 15 months after hospital admission for an acute coronary event or procedure. Readiness for smoking cessation was assessed using the smoking stages of change (SSC) short form questionnaire. Breath carbon monoxide was measured to validate self-reported non-smoking. Results: Among 2585 patients who were smoking prior to hospital admission, 25.6%, 16.8%, 8.1%, 5.6% and 44.0% were in the precontemplation (no intention to quit), contemplation (thinking of quitting), preparation (planning to quit), action (having quit within six months) and maintenance (having quit more than six months ago) stages, respectively. Significant multivariable correlates of advancement in SSC showed positive associations of older age and attended cardiac rehabilitation and negative associations of severe depressive symptoms, longer smoking duration and environmental tobacco smoke (ETS) exposure. Conclusions: One-quarter of CHD patients across Europe who were smoking prior to hospitalisation have no intention to quit, and an additional quarter is thinking of quitting or planning to quit. Patients who are younger, do not attend cardiac rehabilitation, have severe depressive symptoms, have been smoking for longer periods of time and are exposed to ETS may need to be specifically targeted in cessation interventions

    II Congrés Internacional sobre Traducció : abril 1994 : actes

    Get PDF
    Machine learning-based approach unravels distinct pathological signatures induced by patient-derived α-synuclein seeds in monkeys. Dopaminergic neuronal cell death, associated with intracellular α-synuclein (α-syn)-rich protein aggregates [termed "Lewy bodies" (LBs)], is a well-established characteristic of Parkinson's disease (PD). Much evidence, accumulated from multiple experimental models, has suggested that α-syn plays a role in PD pathogenesis, not only as a trigger of pathology but also as a mediator of disease progression through pathological spreading. Here, we have used a machine learning-based approach to identify unique signatures of neurodegeneration in monkeys induced by distinct α-syn pathogenic structures derived from patients with PD. Unexpectedly, our results show that, in nonhuman primates, a small amount of singular α-syn aggregates is as toxic as larger amyloid fibrils present in the LBs, thus reinforcing the need for preclinical research in this species. Furthermore, our results provide evidence supporting the true multifactorial nature of PD, as multiple causes can induce a similar outcome regarding dopaminergic neurodegeneratio

    Polymer-Based Reconstruction of the Inferior Vena Cava in Rat: Stem Cells or RGD Peptide?

    Get PDF
    As part of a program targeted at developing a resorbable valved tube for replacement of the right ventricular outflow tract, we compared three biopolymers (polyurethane [PU], polyhydroxyalkanoate (the poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxyvalerate) [PHBVV]), and polydioxanone [PDO]) and two biofunctionalization techniques (using adipose-derived stem cells [ADSCs] or the arginine-glycine-aspartate [RGD] peptide) in a rat model of partial inferior vena cava (IVC) replacement. Fifty-three Wistar rats first underwent partial replacement of the IVC with an acellular electrospun PDO, PU, or PHBVV patch, and 31 nude rats subsequently underwent the same procedure using a PDO patch biofunctionalized either by ADSC or RGD. Results were assessed both in vitro (proliferation and survival of ADSC seeded onto the different materials) and in vivo by magnetic resonance imaging (MRI), histology, immunohistochemistry [against markers of vascular cells (von Willebrand factor [vWF], smooth muscle actin [SMA]), and macrophages ([ED1 and ED2] immunostaining)], and enzyme-linked immunosorbent assay (ELISA; for the expression of various cytokines and inducible NO synthase). PDO showed the best in vitro properties. Six weeks after implantation, MRI did not detect significant luminal changes in any group. All biopolymers were evenly lined by vWF-positive cells, but only PDO and PHBVV showed a continuous layer of SMA-positive cells at 3 months. PU patches resulted in a marked granulomatous inflammatory reaction. The ADSC and RGD biofunctionalization yielded similar outcomes. These data confirm the good biocompatibility of PDO and support the concept that appropriately peptide-functionalized polymers may be successfully substituted for cell-loaded materials

    Insufficient OPC migration into demyelinated lesions is a cause of poor remyelination in MS and mouse models

    Get PDF
    Failure of remyelination of multiple sclerosis (MS) lesions contributes to neurodegeneration that correlates with chronic disability in patients. Currently, there are no available treatments to reduce neurodegeneration, but one therapeutic approach to fill this unmet need is to promote remyelination. As many demyelinated MS lesions contain plentiful oligodendrocyte precursor cells (OPCs), but no mature myelinating oligodendrocytes, research has previously concentrated on promoting OPC maturation. However, some MS lesions contain few OPCs, and therefore, remyelination failure may also be secondary to OPC recruitment failure. Here, in a series of MS samples, we determined how many lesions contained few OPCs, and correlated this to pathological subtype and expression of the chemotactic molecules Semaphorin (Sema) 3A and 3F. 37 % of MS lesions contained low numbers of OPCs, and these were mostly chronic active lesions, in which cells expressed Sema3A (chemorepellent). To test the hypothesis that differential Sema3 expression in demyelinated lesions alters OPC recruitment and the efficiency of subsequent remyelination, we used a focal myelinotoxic mouse model of demyelination. Adding recombinant (r)Sema3A (chemorepellent) to demyelinated lesions reduced OPC recruitment and remyelination, whereas the addition of rSema3F (chemoattractant), or use of transgenic mice with reduced Sema3A expression increased OPC recruitment and remyelination. We conclude that some MS lesions fail to remyelinate secondary to reduced OPC recruitment, and that chemotactic molecules are involved in the mechanism, providing a new group of drug targets to improve remyelination, with a specific target in the Sema3A receptor neuropilin-1. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00401-013-1112-y) contains supplementary material, which is available to authorized users

    PINK1 Is Necessary for Long Term Survival and Mitochondrial Function in Human Dopaminergic Neurons

    Get PDF
    Parkinson's disease (PD) is a common age-related neurodegenerative disease and it is critical to develop models which recapitulate the pathogenic process including the effect of the ageing process. Although the pathogenesis of sporadic PD is unknown, the identification of the mendelian genetic factor PINK1 has provided new mechanistic insights. In order to investigate the role of PINK1 in Parkinson's disease, we studied PINK1 loss of function in human and primary mouse neurons. Using RNAi, we created stable PINK1 knockdown in human dopaminergic neurons differentiated from foetal ventral mesencephalon stem cells, as well as in an immortalised human neuroblastoma cell line. We sought to validate our findings in primary neurons derived from a transgenic PINK1 knockout mouse. For the first time we demonstrate an age dependent neurodegenerative phenotype in human and mouse neurons. PINK1 deficiency leads to reduced long-term viability in human neurons, which die via the mitochondrial apoptosis pathway. Human neurons lacking PINK1 demonstrate features of marked oxidative stress with widespread mitochondrial dysfunction and abnormal mitochondrial morphology. We report that PINK1 plays a neuroprotective role in the mitochondria of mammalian neurons, especially against stress such as staurosporine. In addition we provide evidence that cellular compensatory mechanisms such as mitochondrial biogenesis and upregulation of lysosomal degradation pathways occur in PINK1 deficiency. The phenotypic effects of PINK1 loss-of-function described here in mammalian neurons provides mechanistic insight into the age-related degeneration of nigral dopaminergic neurons seen in PD
    • …
    corecore