89 research outputs found
IntĂ©rĂȘt Dâune Recherche De Thrombophilie Au Cours Des Thromboses De La Veine Porte Dans Un Service De MĂ©decine Interne
Background: Many causes of portal vein thrombosis are described and most patients had a combination of local and systemic risk factors. In many studies, prtothombotic disorders investigations were conducted in various departments of haematologies and/or gastroenterology. In this study, we investigated the systemic risk factors associated or not to abdominal inflammation in a series of patients recruited in a department of Internal Medicine. Methods: We studied, retrospectively from 2005 to 2009, 21 cases of patients with portal vein thrombosis. Patients with cancer are not included in this study. Results: We reported 21 patients with portal vein thrombosis: 8 males (43%) and 13 females (57%). The average age of patients was 46, 6 years (20; 59). Eight (8) patients had abdominal inflammatory pathology and 21 (100%) patients had systemic prothrombotic factors. This etiologic investigation is rentable because in 18 cases, abdominal inflammation and/or prothombotic disorders are diagnosed. This diagnostic, however, can permit to discuss a specific management. Conclusion: Extensive investigation of prothrombotic disorders is necessary in portal vein thrombosis, although if local abdominal inflammation exist
Pattern of DAP12 Expression in Leukocytes from Both Healthy and Systemic Lupus Erythematosus Patients
DAP12 is an ITAM-bearing transmembrane adaptor originally identified on the surface of Natural Killer cells. A broad expression among other immune cells was later found in myeloid and lymphoid cells. However, data on DAP12 expression pattern rely only on immunoblot and microarray analysis. Here, we describe the generation and the characterization of an anti-DAP12 monoclonal antibody. Using this novel reagent, we show that DAP12 expression is restricted to innate immune cells in basal condition. Since a decreased expression of DAP12 has been suggested in NK cells of systemic lupus erythematosus patients, we have further investigated the NK cell receptor repertoire and leukocyte expression of DAP12 in these patients and no major changes were detectable when compared to controls
Uncommon mutational profiles of metastatic colorectal cancer detected during routine genotyping using next generation sequencing
RAS genotyping is mandatory to predict anti-EGFR monoclonal antibodies (mAbs) therapy resistance and BRAF genotyping is a relevant prognosis marker in patients with metastatic colorectal cancer. Although the role of hotspot mutations is well defined, the impact of uncommon mutations is still unknown. In this study, we aimed to discuss the potential utility of detecting uncommon RAS and BRAF mutation profiles with next-generation sequencing. A total of 779 FFPE samples from patients with metastatic colorectal cancer with valid NGS results were screened and 22 uncommon mutational profiles of KRAS, NRAS and BRAF genes were selected. In silico prediction of mutation impact was then assessed by 2 predictive scores and a structural protein modelling. Three samples carry a single KRAS non-hotspot mutation, one a single NRAS non-hotspot mutation, four a single BRAF non-hotspot mutation and fourteen carry several mutations. This in silico study shows that some non-hotspot RAS mutations seem to behave like hotspot mutations and warrant further examination to assess whether they should confer a resistance to anti-EGFR mAbs therapy for patients bearing these non-hotspot RAS mutations. For BRAF gene, non-V600E mutations may characterise a novel subtype of mCRC with better prognosis, potentially implying a modification of therapeutic strategy
Macroautophagy in Dendritic Cells Controls the Homeostasis and Stability of Regulatory T Cells.
Regulatory T cells (Tregs) play a crucial role in controlling autoimmune and inflammatory responses. Recent studies have demonstrated that dendritic cells (DCs) contribute to the homeostasis of peripheral Tregs. Autophagy, a critical pathway for cellular homeostasis, is active in DCs and is upregulated in different inflammatory conditions. We have shown that Tregs are expanded and have phenotypic alterations and impaired suppressive functions in mice with autophagy-deficient DCs. RNA profiling of Tregs revealed that autophagy in DCs is required to stabilize Treg expression signatures. This phenotype is linked to the downregulation of ICOS-Ligand expression in autophagy-deficient DCs, a consequence of the accumulation of ADAM10, the metalloproteinase responsible for its cleavage. Upon inflammation, in antigen-induced arthritis, mice with autophagy-deficient DCs exhibit increased synovial inflammation and cartilage and bone erosion correlating with Treg-to-Th17 conversion. Our data reveal a mechanism that couples autophagy deficiency in DCs to the function, homeostasis, and stability of Tregs
A computational psychiatry approach identifies how alpha-2A noradrenergic agonist Guanfacine affects feature-based reinforcement learning in the macaque
[EN] Noradrenaline is believed to support cognitive flexibility through the alpha 2A noradrenergic receptor (a2A-NAR) acting in prefrontal cortex. Enhanced flexibility has been inferred from improved working memory with the a2A-NA agonist Guanfacine. But it has been unclear whether Guanfacine improves specific attention and learning mechanisms beyond working memory, and whether the drug effects can be formalized computationally to allow single subject predictions. We tested and confirmed these suggestions in a case study with a healthy nonhuman primate performing a feature-based reversal learning task evaluating performance using Bayesian and Reinforcement learning models. In an initial dose-testing phase we found a Guanfacine dose that increased performance accuracy, decreased distractibility and improved learning. In a second experimental phase using only that dose we examined the faster feature-based reversal learning with Guanfacine with single-subject computational modeling. Parameter estimation suggested that improved learning is not accounted for by varying a single reinforcement learning mechanism, but by changing the set of parameter values to higher learning rates and stronger suppression of non-chosen over chosen feature information. These findings provide an important starting point for developing nonhuman primate models to discern the synaptic mechanisms of attention and learning functions within the context of a computational neuropsychiatry framework.This research was supported by grants from the Canadian Institutes of Health Research (CIHR), the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Ontario Ministry of Economic Development and Innovation (MEDI). We thank Dr. Hongying Wang for invaluable help with drug administration and animal careHassani, SA.; Oemisch, M.; Balcarras, M.; Westendorff, S.; Ardid-RamĂrez, JS.; Van Der Meer, MA.; Tiesinga, P.... (2017). A computational psychiatry approach identifies how alpha-2A noradrenergic agonist Guanfacine affects feature-based reinforcement learning in the macaque. Scientific Reports. 7:1-19. https://doi.org/10.1038/srep40606S1197Arnsten, A. F., Wang, M. J. & Paspalas, C. D. Neuromodulation of thought: flexibilities and vulnerabilities in prefrontal cortical network synapses. Neuron 76, 223â239 (2012).Arnsten, A. F. & Dudley, A. G. Methylphenidate improves prefrontal cortical cognitive function through alpha2 adrenoceptor and dopamine D1 receptor actions: Relevance to therapeutic effects in Attention Deficit Hyperactivity Disorder. Behav Brain Funct 1, 2 (2005).Clark, K. L. & Noudoost, B. The role of prefrontal catecholamines in attention and working memory. Front Neural Circuits 8, 33 (2014).Wang, M. et al. Neuronal basis of age-related working memory decline. Nature 476, 210â213 (2011).Wang, M. et al. Alpha2A-adrenoceptors strengthen working memory networks by inhibiting cAMP-HCN channel signaling in prefrontal cortex. Cell 129, 397â410 (2007).Aston-Jones, G. & Cohen, J. D. An integrative theory of locus coeruleus-norepinephrine function: adaptive gain and optimal performance. Annu Rev Neurosci 28, 403â450 (2005).Yu, A. J. & Dayan, P. Uncertainty, neuromodulation, and attention. Neuron 46, 681â692 (2005).Mather, M., Clewett, D., Sakaki, M. & Harley, C. W. Norepinephrine ignites local hot spots of neuronal excitation: How arousal amplifies selectivity in perception and memory. Behav Brain Sci, 1â100, doi: 10.1017/S0140525X15000667 (2015).Amemiya, S. & Redish, A. D. Manipulating Decisiveness in Decision Making: Effects of Clonidine on Hippocampal Search Strategies. J Neurosci 36, 814â827 (2016).Doya, K. Metalearning and neuromodulation. Neural Netw 15, 495â506 (2002).Uhlen, S., Muceniece, R., Rangel, N., Tiger, G. & Wikberg, J. E. Comparison of the binding activities of some drugs on alpha 2A, alpha 2B and alpha 2C-adrenoceptors and non-adrenergic imidazoline sites in the guinea pig. Pharmacology & toxicology 76, 353â364 (1995).Mao, Z. M., Arnsten, A. F. & Li, B. M. Local infusion of an alpha-1 adrenergic agonist into the prefrontal cortex impairs spatial working memory performance in monkeys. Biological psychiatry 46, 1259â1265 (1999).Arnsten, A. F. & Goldman-Rakic, P. S. Analysis of alpha-2 adrenergic agonist effects on the delayed nonmatch-to-sample performance of aged rhesus monkeys. Neurobiol Aging 11, 583â590 (1990).Franowicz, J. S. & Arnsten, A. F. The alpha-2a noradrenergic agonist, guanfacine, improves delayed response performance in young adult rhesus monkeys. Psychopharmacology 136, 8â14 (1998).Caetano, M. S. et al. Noradrenergic control of error perseveration in medial prefrontal cortex. Frontiers in Integrative Neuroscience 6, 125 (2012).Kim, S., Bobeica, I., Gamo, N. J., Arnsten, A. F. & Lee, D. Effects of alpha-2A adrenergic receptor agonist on time and risk preference in primates. Psychopharmacology 219, 363â375 (2012).Seu, E., Lang, A., Rivera, R. J. & Jentsch, J. D. Inhibition of the norepinephrine transporter improves behavioral flexibility in rats and monkeys. Psychopharmacology 202, 505â519 (2009).Kawaura, K., Karasawa, J., Chaki, S. & Hikichi, H. Stimulation of postsynapse adrenergic alpha2A receptor improves attention/cognition performance in an animal model of attention deficit hyperactivity disorder. Behav Brain Res 270, 349â356 (2014).Aoki, C., Go, C. G., Venkatesan, C. & Kurose, H. Perikaryal and synaptic localization of alpha 2A-adrenergic receptor-like immunoreactivity. Brain Res 650, 181â204 (1994).Barth, A. M., Vizi, E. S., Zelles, T. & Lendvai, B. Alpha2-adrenergic receptors modify dendritic spike generation via HCN channels in the prefrontal cortex. J Neurophysiol 99, 394â401 (2008).Ji, X. H., Ji, J. Z., Zhang, H. & Li, B. M. Stimulation of alpha2-adrenoceptors suppresses excitatory synaptic transmission in the medial prefrontal cortex of rat. Neuropsychopharmacology 33, 2263â2271 (2008).Yi, F., Liu, S. S., Luo, F., Zhang, X. H. & Li, B. M. Signaling mechanism underlying alpha2A -adrenergic suppression of excitatory synaptic transmission in the medial prefrontal cortex of rats. Eur J Neurosci 38, 2364â2373 (2013).Engberg, G. & Eriksson, E. Effects of alpha 2-adrenoceptor agonists on locus coeruleus firing rate and brain noradrenaline turnover in N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ)-treated rats. Naunyn-Schmiedebergâs archives of pharmacology 343, 472â477 (1991).Jakala, P. et al. Guanfacine, but not clonidine, improves planning and working memory performance in humans. Neuropsychopharmacology 20, 460â470 (1999).Jakala, P. et al. Guanfacine and clonidine, alpha 2-agonists, improve paired associates learning, but not delayed matching to sample, in humans. Neuropsychopharmacology 20, 119â130 (1999).Muller, U. et al. Lack of effects of guanfacine on executive and memory functions in healthy male volunteers. Psychopharmacology 182, 205â213 (2005).Scahill, L. et al. A placebo-controlled study of guanfacine in the treatment of children with tic disorders and attention deficit hyperactivity disorder. The American journal of psychiatry 158, 1067â1074 (2001).Huys, Q. J. M., Maia, T. V. & Frank, M. J. Computational psychiatry as a bridge from neuroscience to clinical applications. Nat Neurosci 19, 404â413 (2016).Stephan, K. E. et al. Computational neuroimaging strategies for single patient predictions. NeuroImage in press (2015).Arnsten, A. F., Cai, J. X. & Goldman-Rakic, P. S. The alpha-2 adrenergic agonist guanfacine improves memory in aged monkeys without sedative or hypotensive side effects: evidence for alpha-2 receptor subtypes. J Neurosci 8, 4287â4298 (1988).Callado, L. F. & Stamford, J. A. Alpha2A- but not alpha2B/C-adrenoceptors modulate noradrenaline release in rat locus coeruleus: voltammetric data. Eur J Pharmacol 366, 35â39 (1999).Millan, M. J. et al. Cognitive dysfunction in psychiatric disorders: characteristics, causes and the quest for improved therapy. Nature reviews. Drug discovery 11, 141â168 (2012).Niv, Y. et al. Reinforcement learning in multidimensional environments relies on attention mechanisms. J Neurosci 35, 8145â8157 (2015).Balcarras, M., Ardid, S., Kaping, D., Everling, S. & Womelsdorf, T. Attentional Selection Can Be Predicted by Reinforcement Learning of Task-relevant Stimulus Features Weighted by Value-independent Stickiness. J Cogn Neurosci 28, 333â349 (2016).Redish, A. D., Jensen, S., Johnson, A. & Kurth-Nelson, Z. Reconciling reinforcement learning models with behavioral extinction and renewal: implications for addiction, relapse, and problem gambling. Psychol Rev 114, 784â805 (2007).Nassar, M. R. et al. Rational regulation of learning dynamics by pupil-linked arousal systems. Nat Neurosci 15, 1040â1046 (2012).OâReilly, J. X. et al. Dissociable effects of surprise and model update in parietal and anterior cingulate cortex. Proc Natl Acad Sci USA 110, 3660â3669 (2013).Shenhav, A., Botvinick, M. M. & Cohen, J. D. The expected value of control: an integrative theory of anterior cingulate cortex function. Neuron 79, 217â240 (2013).Womelsdorf, T. & Everling, S. Long-Range Attention Networks: Circuit Motifs Underlying Endogenously Controlled Stimulus Selection. Trends Neurosci 38, 682â700 (2015).Yang, Y. et al. Nicotinic alpha7 receptors enhance NMDA cognitive circuits in dorsolateral prefrontal cortex. Proc Natl Acad Sci USA 110, 12078â12083 (2013).Aston-Jones, G., Rajkowski, J. & Cohen, J. Role of locus coeruleus in attention and behavioral flexibility. Biological psychiatry 46, 1309â1320 (1999).Cole, B. J. & Robbins, T. W. Forebrain norepinephrine: role in controlled information processing in the rat. Neuropsychopharmacology 7, 129â142 (1992).Dalley, J. W., Cardinal, R. N. & Robbins, T. W. Prefrontal executive and cognitive functions in rodents: neural and neurochemical substrates. Neuroscience and biobehavioral reviews 28, 771â784 (2004).Devauges, V. & Sara, S. J. Activation of the noradrenergic system facilitates an attentional shift in the rat. Behav Brain Res 39, 19â28 (1990).Connor, D. F., Arnsten, A. F., Pearson, G. S. & Greco, G. F. Guanfacine extended release for the treatment of attention-deficit/hyperactivity disorder in children and adolescents. Expert opinion on pharmacotherapy 15, 1601â1610 (2014).Sallee, F. R. et al. Guanfacine extended release in children and adolescents with attention-deficit/hyperactivity disorder: a placebo-controlled trial. J Am Acad Child Adolesc Psychiatry 48, 155â165 (2009).Steere, J. C. & Arnsten, A. F. The alpha-2A noradrenergic receptor agonist guanfacine improves visual object discrimination reversal performance in aged rhesus monkeys. Behav Neurosci 111, 883â891 (1997).Doya, K. Modulators of decision making. Nat Neurosci 11, 410â416 (2008).Wang, X. J. & Krystal, J. H. Computational psychiatry. Neuron 84, 638â654 (2014).Wiecki, T. V. et al. A Computational Cognitive Biomarker for Early-Stage Huntingtonâs Disease. PLoS One 11, e0148409, doi: 10.1371/journal.pone.0148409 (2016).Huys, Q. J., Pizzagalli, D. A., Bogdan, R. & Dayan, P. Mapping anhedonia onto reinforcement learning: a behavioural meta-analysis. Biol Mood Anxiety Disord 3, 12 (2013).Gershman, S. J. & Niv, Y. Learning latent structure: carving nature at its joints. Curr Opin Neurobiol 20, 251â256 (2010).Voon, V. et al. Disorders of compulsivity: a common bias towards learning habits. Mol Psychiatry 20, 345â352 (2015).Maia, T. V. & Frank, M. J. From reinforcement learning models to psychiatric and neurological disorders. Nature Neuroscience 14, 154â162 (2011).Adams, R. A., Huys, Q. J. M. & Roiser, J. P. Computational Psychiatry: towards a mathematically informed understanding of mental illness. Journal of Neurology, Neurosurgery, and Psychiatry 87, 53â63 (2015).Schlagenhauf, F. et al. Striatal dysfunction during reversal learning in unmedicated schizophrenia patients. NeuroImage 89, 171â180 (2014).HarlĂ©, K. M. et al. Bayesian neural adjustment of inhibitory control predicts emergence of problem stimulant use. Brain 138, 3413â3426 (2015).Zhang, J. et al. Different decision deficits impair response inhibition in progressive supranuclear palsy and Parkinsonâs disease. Brain 139, 161â173 (2016).Frank, M. J. et al. fMRI and EEG Predictors of Dynamic Decision Parameters during Human Reinforcement Learning. Journal of Neuroscience 35, 485â494 (2015).Smith, A. C. & Brown, E. N. Estimating a state-space model from point process observations. Neural Comput 15, 965â991 (2003).Wilson, R. C. & Niv, Y. Inferring relevance in a changing world. Frontiers in human neuroscience 5, 189 (2011).RĂ€mĂ€, P. et al. Medetomidine, atipamezole, and guanfacine in delayed response performance of aged monkeys. Pharmacology Biochemistry and Behavior 55, 415â422 (1996).Arnsten, A. F. T. & Contant, T. A. Alpha-2 adrenergic agonists decrease distractibility in aged monkeys performing the delayed response task. Psychopharmacology 108, 159â169 (1992).OâNeill, J. et al. Effects of guanfacine on three forms of distraction in the aging macaque. Life Sciences 67, 877â885 (2000).Wang, M., Ji, J.-Z. & Li, B.-M. The α2A-Adrenergic Agonist Guanfacine Improves Visuomotor Associative Learning in Monkeys. Neuropsychopharmacology 29, 86â92 (2004).Witte, E. a. & Marrocco, R. T. Alteration of brain noradrenergic activity in rhesus monkeys affects the alerting component of covert orienting. Psychopharmacology 132, 315â323 (1997).Decamp, E., Clark, K. & Schneider, J. S. Effects of the alpha-2 adrenoceptor agonist guanfacine on attention and working memory in aged non-human primates. European Journal of Neuroscience 34, 1018â1022 (2011)
Expectations and outcome: The role of Proposer features in the Ultimatum Game
Item does not contain fulltextIn social decision-making individuals make choices in an interactive context and their decisions may therefore be influenced by information they receive about features of the other player. These features may 'frame' the other player in particular ways and generate expectations about the outcome. This research examines the impact of information about the Proposer on the Responder's decision in the Ultimatum Game (UG).
Two-hundred and forty undergraduates played the UG after being provided with different descriptions of the Proposer's (no information, physical description, psychological description). The results show that acceptance rates are significantly influenced by both offer fairness as well as the type of description. These results support the relevance of the expectation effects due to the framing in social decision making
Characteristics of Systemic Sclerosis patients with positive anti-Th/To antibodies: About 6 patients and literature review
International audienceAmong the antibodies described in Systemic Sclerosis (SSc), anti-Th/To antibodies (anti-Th/To) are rare and have been poorly studied. Thus, little is known about the profile of anti-Th/To positive patients. From our local Biobank (Marseille, France), we retrospectively selected data for 6 patients positive for anti-Th/To with an Immunodot assay. All of them suffered from SSc, sharing clinical and biological common features such as a limited cutaneous form of SSc, a decreased lung diffusing capacity and a speckled nuclear nucleolar immunofluorescence pattern of antinuclear antibodies screening on HEp-2 cells. In order to further characterize patients positive for anti-Th/To, we performed a thorough literature review. From 402 studied patients positive for anti-Th/To, we confirmed that these antibodies are associated with the limited cutaneous form of the disease (88% of the patients), and with an SSc related-pulmonary involvement (50%). The review analysis pointed out the rarity of the anti-Th/To with an estimated mean frequency of 3.4% of all SSc patients worldwide, their usual exclusivity with respect to the specific antibodies of scleroderma, and their high specificity (around 98%) for the diagnosis of SSc.Parmi les anticorps dĂ©crits associĂ©s Ă la SclĂ©rodermie SystĂ©mique (ScS), les anticorps anti-Th/To (anti-Th/To) sont rares et ont Ă©tĂ© peu Ă©tudiĂ©s. Ainsi, nous nâavons que peu de connaissance sur le profil des patients positifs pour les anti-Th/To. Ă partir dâune Biobanque locale (Marseille, France), nous avons sĂ©lectionnĂ© de façon rĂ©trospective 6 patients positifs pour les anti-Th/To, en test Immunodot. Tous souffraient de ScS et partageaient des caractĂ©ristiques cliniques et biologiques communes, comme la forme cutanĂ©e limitĂ©e de la ScS, une baisse de la diffusion alvĂ©olocapillaire pulmonaire et un aspect mouchetĂ© nuclĂ©olaire en immunofluorescence indirecte au test de dĂ©pistage des anticorps anti-nuclĂ©aires sur cellules Hep-2. Afin de caractĂ©riser davantage les patients positifs pour les anti-Th/To, nous avons rĂ©alisĂ© une revue de la littĂ©rature sur le sujet. Ă partir de lâĂ©tude de 402 patients positifs pour les anti-Th/To, nous confirmons que ces anticorps sont principalement associĂ©s Ă la forme cutanĂ©e limitĂ©e de la maladie (88 % de lâensemble des patients), et Ă une atteinte pulmonaire de la ScS (50 % de lâensemble des patients). Cette analyse de la littĂ©rature illustre la raretĂ© des anti-Th/To avec une frĂ©quence moyenne estimĂ©e de 3,4 % chez tous les patients souffrant de ScS dans le monde entier, leur caractĂšre habituellement exclusif vis-Ă -vis des autres autoanticorps spĂ©cifiques de la SclĂ©rodermie, ainsi que leur grande spĂ©cificitĂ© (environ 98 %) pour le diagnostic de la ScS
- âŠ