Staphylocoques et autres bactéries à gram positif: Détection de la pénicillinase de Staphylococcus aureus : quand cela paraît flou.

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GluD1, linked to schizophrenia, controls the burst firing of dopamine neurons

Human mutations of the GRID1 gene encoding the orphan delta1 glutamate receptor-channel (GluD1) are associated with schizophrenia but the explicit role of GluD1 in brain circuits is unknown. Based on the known function of its paralog GluD2 in cerebellum, we searched for a role of GluD1 in slow glutamatergic transmission mediated by metabotropic receptor mGlu1 in midbrain dopamine neurons, whose dysfunction is a hallmark of schizophrenia. We found that an mGlu1 agonist elicits a slow depolarizing current in HEK cells co-expressing mGlu1 and GluD1, but not in cells expressing mGlu1 or GluD1 alone. This current is abolished by additional co-expression of a dominant-negative GluD1 dead pore mutant. We then characterized mGlu1-dependent currents in dopamine neurons from midbrain slices. Both the agonist-evoked and the slow postsynaptic currents are abolished by expression of the dominant-negative GluD1 mutant, pointing to the involvement of native GluD1 channels in these currents. Likewise, both mGlu1-dependent currents are suppressed in GRID1 knockout mice, which reportedly display endophenotypes relevant for schizophrenia. It is known that mGlu1 activation triggers the transition from tonic to burst firing of dopamine neurons, which signals salient stimuli and encodes reward prediction. In vivo recordings of dopamine neurons showed that their spontaneous burst firing is abolished in GRID1 knockout mice or upon targeted expression of the dominant-negative GluD1 mutant in wild-type mice. Our results de-orphanize GluD1, unravel its key role in slow glutamatergic transmission and provide insights into how GRID1 gene alterations can lead to dopaminergic dysfunctions in schizophrenia

Pleistocene terrace deposition related to tectonically controlled surface uplift: an example of the Kyrenia Range lineament in the northern part of Cyprus

AbstractIn this study, we consider how surface uplift of a narrow mountain range has interacted with glacial-related sea-level cyclicity and climatic change to produce a series of marine and non-marine terrace systems. The terrace deposits of the Kyrenia Range record rapid surface uplift of a long-lived tectonic lineament during the early Pleistocene, followed by continued surface uplift at a reduced rate during mid-late Pleistocene. Six terrace depositional systems are distinguished and correlated along the northern and southern flanks of the range, termed K0 to K5. The oldest and highest (K0 terrace system) is present only within the central part of the range. The K2–K5 terrace systems formed later, at sequentially lower levels away from the range. The earliest stage of surface uplift (K0 terrace system) comprises lacustrine carbonates interbedded with mass-flow facies (early Pleistocene?). The subsequent terrace system (K1) is made up of colluvial conglomerate and aeolian dune facies on both flanks of the range. The later terrace systems (K2 to K5) each begin with a basal marine deposit, interpreted as a marine transgression. Deltaic conglomerates prograded during inferred global interglacial stages. Overlying aeolian dune facies represent marine regressions, probably related to global glacial stages. Each terrace depositional system was uplifted and preserved, followed by subsequent deposits at progressively lower topographic levels. Climatic variation during interglacial–glacial cycles and autocyclic processes also exerted an influence on deposition, particularly on short-period fluvial and aeolian deposition

Revised diagnostic criteria for neurofibromatosis type 1 and Legius syndrome: an international consensus recommendation

Abstract Purpose By incorporating major developments in genetics, ophthalmology, dermatology, and neuroimaging, to revise the diagnostic criteria for neurofibromatosis type 1 (NF1) and to establish diagnostic criteria for Legius syndrome (LGSS). Methods We used a multistep process, beginning with a Delphi method involving global experts and subsequently involving non-NF experts, patients, and foundations/patient advocacy groups. Results We reached consensus on the minimal clinical and genetic criteria for diagnosing and differentiating NF1 and LGSS, which have phenotypic overlap in young patients with pigmentary findings. Criteria for the mosaic forms of these conditions are also recommended. Conclusion The revised criteria for NF1 incorporate new clinical features and genetic testing, whereas the criteria for LGSS were created to differentiate the two conditions. It is likely that continued refinement of these new criteria will be necessary as investigators (1) study the diagnostic properties of the revised criteria, (2) reconsider criteria not included in this process, and (3) identify new clinical and other features of these conditions. For this reason, we propose an initiative to update periodically the diagnostic criteria for NF1 and LGSS. </jats:sec

Recurrent recovery of Pseudomonas oryzihabitans strains in a karstified chalk aquifer

International audiencePseudomonas oryzihabitans is an uncommon pathogen that may cause catheter-associated infections, particularly in immunocompromised patients. Although it has been isolated from environment, the source of human infection is not well documented. In the present study, 14 isolates of P. oryzihabitans were recovered over a 28-month period from a karstified chalk aquifer, allowing to advance that distributed natural water could be a source of contamination. Microbiological analyses showed that the bacterium was mainly associated with suspended particulate matters. To investigate the clonality of P. oryzihabitans environmental isolates, 16S rRNA gene sequencing, antibiogram and randomly amplified polymorphic DNA (RAPD) typings were performed. Results demonstrated (i) the presence of at least three clones within the aquifer and (ii) that the presence of the bacterium in groundwater is not only the result of a biofilm bloom but also of an exogenous contamination

Staphylocoques et autres bactéries à gram positif: Détection de la pénicillinase de Staphylococcus aureus : quand cela paraît flou.

International audienc

Diagnostic value of CA19.9, circulating tumour DNA and circulating tumour cells in patients with solid pancreatic tumours

International audienceBackground: The direct comparison of CA19.9, circulating tumour cells (CTCs) and circulating tumour DNA (ctDNA) using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has never been performed for the diagnosis of solid pancreatic tumours (SPTs).Methods: We included 68 patients with a SPT referred for EUS-FNA. CTCs were analysed using size-based platform and ctDNA using digital PCR. The sensitivity, specificity, negative and positive predictive values were evaluated for each marker and their combination.Results: SPTs corresponded to 58 malignant tumours (52 pancreatic adenocarcinoma (PA) and 6 others) and 10 benign lesions. The sensitivity and specificity for PA diagnosis were 73% and 88% for EUS-FNA, 67% and 80% for CTC, 65% and 75% for ctDNA and 79% and 93% for CA19.9, respectively. The positivity of at least 2 markers was associated with a sensitivity and specificity of 78% and 91%, respectively. CtDNA was the only marker associated with overall survival (median 5.2 months for ctDNA þ vs 11.0 months for ctDNA , P 1⁄4 0.01).Conclusions: CA19.9 alone and in combination with ctDNA and/or CTC analysis may represent an efficient method for diagnosing PA in patients with SPTs. Further studies including a larger cohort of patients with both malignant and benign lesions will be necessary to confirm these promising results