Microglial TNFα controls daily changes in synaptic GABAARs and sleep slow waves.

Microglia sense the changes in their environment. How microglia actively translate these changes into suitable cues to adapt brain physiology is unknown. We reveal an activity-dependent regulation of cortical inhibitory synapses by microglia, driven by purinergic signaling acting on P2RX7 and mediated by microglia-derived TNFα. We demonstrate that sleep induces microglia-dependent synaptic enrichment of GABAARs in a manner dependent on microglial TNFα and P2RX7. We further show that microglia-specific depletion of TNFα alters slow waves during NREM sleep and blunt memory consolidation in sleep-dependent learning tasks. Together, our results reveal that microglia orchestrate sleep-intrinsic plasticity of synaptic GABAARs, sculpt sleep slow waves, and support memory consolidation.

Initial characteristics and course of disease in patients with suspected COVID-19 managed in general practice: a prospective, multicentre cohort study.

OBJECTIVES: To describe and compare the initial clinical characteristics of a cohort of patients with suspected COVID-19 managed by general practitioners (GPs); to assess whether 3-month persistent symptoms were more frequent among confirmed cases than among no-COVID cases; and to identify factors predictive of persistent symptoms and adverse outcomes among confirmed cases. DESIGN AND SETTING: A comparative, prospective, multicentre cohort study in primary care in the Paris region of France. PARTICIPANTS: 521 patients aged ≥18 with suspected COVID-19 were enrolled between March and May 2020. OUTCOME MEASURES: Initial symptoms, COVID-19 status, persistent symptoms 3 months after inclusion and a composite criterion for potentially COVID-19-related events (hospitalisation, death, emergency department visits). The final COVID-19 status ('confirmed', 'no-COVID' and 'uncertain' cases) was determined by the GP after the receipt of the laboratory test results. RESULTS: 516 patients were analysed; 166 (32.2%) were classified into the 'confirmed COVID' group, 180 (34.9%) into the 'no-COVID' group and 170 (32.9%) in the 'uncertain COVID' group. Confirmed cases were more likely to have persistent symptoms than no-COVID cases (p=0.09); initial fever/feeling feverish and anosmia were independently associated with persistent symptoms. At 3 months, we observed 16 (9.8%) COVID-19-related hospital admissions, 3 (1.8%) intensive care unit admissions, 13 (37.1%) referrals to an emergency department and no death. Age >70 and/or at least one comorbidity (OR 6.53; 95% CI 1.13-37.84; p=0.036), abnormalities in a lung examination (15.39; 95% CI 1.61-146.77; p=0.057) and two or more systemic symptoms (38.61; 95% CI 2.30-647.40; p=0.011) were associated with the composite criterion. CONCLUSIONS: Although most patients with COVID-19 in primary care had mild disease with a benign course, almost one in six had persistent symptoms at 3 months. These symptoms were more frequent in the 'confirmed COVID' group. Our findings need to be confirmed in a prospective study with longer follow-up.

Visuomotor learning promotes visually evoked activity in the medial prefrontal cortex.

The medial prefrontal cortex (mPFC) is necessary for executing many learned associations between stimuli and movement. It is unclear, however, how activity in the mPFC evolves across learning, and how this activity correlates with sensory stimuli and the learned movements they evoke. To address these questions, we record cortical activity with widefield calcium imaging while mice learned to associate a visual stimulus with a forelimb movement. After learning, the mPFC shows stimulus-evoked activity both during task performance and during passive viewing, when the stimulus evokes no action. This stimulus-evoked activity closely tracks behavioral performance across training, with both exhibiting a marked increase between days when mice first learn the task, followed by a steady increase with further training. Electrophysiological recordings localized this activity to the secondary motor and anterior cingulate cortex. We conclude that learning a visuomotor task promotes a route for visual information to reach the prefrontal cortex.

Inappropriate direct oral anticoagulant prescriptions in patients with non-valvular atrial fibrillation: cross-sectional analysis of the French CACAO cohort study in primary care.

BACKGROUND: Direct oral anticoagulants (DOACs) account for an increasing proportion of prescriptions in patients with non-valvular atrial fibrillation (NVAF) in primary care. Inappropriate dosing of DOACs is a common problem, with under-dosing being a particular issue. However, conflicting results have been reported about the factors independently associated with inappropriate dosing. AIM: To describe inappropriate prescriptions of DOACs among patients in the CACAO French nationwide general practice cohort, and to identify the factors independently associated with inappropriate DOAC doses. DESIGN AND SETTING: Cross-sectional baseline analysis of the CACAO French national multicentre prospective cohort of adult patients in primary care receiving an oral anticoagulant who were recruited between April and October 2014. METHOD: A total of 1111 patients from the CACAO cohort who received a DOAC for NVAF were included in this study. Inappropriate prescriptions of DOACs were described (inappropriate dosage, contraindications, non-indications, interactions, and non-compliance with the precautions for use). Multivariate logistic models were used to investigate factors associated with inappropriate DOAC dosing (under-dosing and over-dosing). RESULTS: Overall, 438 patients (39.4%) received at least one inappropriate DOAC prescription. The most common inappropriate prescription was inappropriate dosage (n = 374, 33.7%), particularly under-dosing (n = 348, 31.3%). Multivariate analysis revealed that factors independently associated with under-dosing were older age, prescription of apixaban or dabigatran, and a CHA2DS2-VASc score ≥2 vs. a score = 1. Factors with over-dosing were kidney failure, a HAS-BLED score ≥3, and older age. CONCLUSION: The appropriateness of DOAC prescribing for NVAF can be improved, especially in older patients, and in patients with kidney failure, a higher risk of ischaemic stroke, and/or a higher risk of bleeding. GPs have a key role in increasing the proportion of appropriate DOAC prescriptions via informational, educational, and/or management strategies.

Striatal activity topographically reflects cortical activity.

The cortex projects to the dorsal striatum topographically1,2 to regulate behaviour3-5, but spiking activity in the two structures has previously been reported to have markedly different relations to sensorimotor events6-9. Here we show that the relationship between activity in the cortex and striatum is spatiotemporally precise, topographic, causal and invariant to behaviour. We simultaneously recorded activity across large regions of the cortex and across the width of the dorsal striatum in mice that performed a visually guided task. Striatal activity followed a mediolateral gradient in which behavioural correlates progressed from visual cue to response movement to reward licking. The summed activity in each part of the striatum closely and specifically mirrored activity in topographically associated cortical regions, regardless of task engagement. This relationship held for medium spiny neurons and fast-spiking interneurons, whereas the activity of tonically active neurons differed from cortical activity with stereotypical responses to sensory or reward events. Inactivation of the visual cortex abolished striatal responses to visual stimuli, supporting a causal role of cortical inputs in driving the striatum. Striatal visual responses were larger in trained mice than untrained mice, with no corresponding change in overall activity in the visual cortex. Striatal activity therefore reflects a consistent, causal and scalable topographical mapping of cortical activity.

Changes over time in attitudes towards the management of older patients with heart failure by general practitioners: a qualitative study.

BACKGROUND: Underdiagnosis and undertreatment of chronic heart failure (CHF) are common in older patients, who are usually treated by general practitioners (GPs). In 2007, the French ICAGE study explored GPs' attitudes to the management of this condition in older patients. OBJECTIVES: To explore changes over time in GPs' attitudes towards the management of CHF in patients aged ≥75 and to identify barriers to optimal management. METHODS: In 2015, we performed a qualitative study of 20 French GPs via semi-structured interviews and a thematic content analysis. The results were compared with the findings of a 2007 study. RESULTS: In 2015, the perceived barriers to diagnosis were the same as in 2007. Echocardiography was still the preferred diagnostic method but the GPs relied on the cardiologist to confirm the diagnosis. Many GPs were still unaware of the different types of CHF. In contrast, they reported greater knowledge of decompensation factors and the ultrasound criteria for CHF. They also prescribed a brain natriuretic peptide assay more frequently. Angiotensin-converting enzyme inhibitors and beta blockers were more strongly perceived to be core treatments. Few GPs initiated drug treatments and optimized dosages. Although patient education was never mentioned, the importance of multidisciplinary care was emphasized. CONCLUSION: Our results evidenced a small recent improvement in the management of older patients with CHF. Appropriate guidelines and training for GPs, patient education and multidisciplinary collaboration might further improve the care given to this population.