Mise au point sur la toxicité de Tricholoma auratum

Le Tricholoma auratum, également nommé Tricholome doré, est un champignon robuste poussant spécifiquement en pinèdes sableuses, le long des côtes. Il est très fréquent sur le littoral atlantique où on l appelle bidaou . Il était auparavant considéré comme bon comestible ; mais il a été incriminé dans plusieurs cas d intoxications graves ces quinze dernières années. Ce champignon peut en effet être à l origine d une rhabdomyolyse, qui s est déjà révélée mortelle. Des études expérimentales ont pu démontrer sa toxicité. Celle-ci n apparaîtrait qu en cas d ingestion répétée de quantités importantes de Tricholoma auratum. Il est donc actuellement recommandé de ne plus consommer de ce champignon. Par principe de précaution, le Tricholoma equestre, taxonomiquement très proche, ne doit plus l être non plus. Un décret paru au Journal Officiel le 19/09/2005 interdit d ailleurs la commercialisation de ces deux espèces.GRENOBLE1-BU Médecine pharm. (385162101) / SudocSudocFranceF

TB/HIV pleurisy reduces Th17 lymphocyte proportion independent of the cytokine microenvironment

T-helper (Th) 17 cells are a pro-inflammatory subset of CD4+ effector T-cells critical in mucosal immunity. Imbalances in Th17 cell proportion have been implicated in the pathogenesis of several diseases; however, this has not been adequately explored in tuberculosis (TB) and human immunodeficiency virus (HIV) co-infection. Since Th17 cells are predominantly mucosally associated, we assessed Th17 proportion and associated microenvironment in pleural effusions from patients co-infected with TB/HIV. Our results show that TB+HIV+ pleurisy results in significantly reduced frequency of CD4+IL-17+RORC+STAT3+ Th17 cells compared to TB−HIV−ex vivo (p = 0.0054) and was confirmed in conditioned media studies in vitro (p = 0.0001). This was not associated with alterations in Th17 polarising cytokines IL-6, IL-21 and IL-23 or changes in Th17 signature cytokines IL-17A and F. However, the mRNA expression of Th17 signalling molecules, IL-6 (p = 0.0022), IL-6R (p = 0.0247), IL-1β (p = 0.0022) and signal transducer and activator (STAT) 3 (p = 0.0022) were significantly upregulated. Notably, TB+HIV+ pleural fluid contained significantly higher concentrations of IL-1β (p = 0.0008), IL-22 (p = 0.0115), IL-31 (p = 0.0210), TNF-α (p = 0.0251) and IFN-γ (p = 0.0026) than TB−HIV− pleural fluid ex vivo. Taken together, this suggests a reduced portion of Th17 lymphocytes in TB/HIV pleurisy is independent of locally mediated cytokine polarisation.The National Research Foundation, KwaZulu-Natal Research Institute for Tuberculosis and HIV and College of Health Sciences, University of KwaZulu-Natal.http://intl.elsevierhealth.com/journals/tube2017-07-31hb2016Physiolog