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Marine Mondino Renaud Jardri Marie-Fran?oise Suaud-Chagny Mohamed Saoud Emmanuel Poulet Jér?me Brunelin 《Schizophrenia bulletin》2016,42(2):318-326
Auditory verbal hallucinations (AVH) in patients with schizophrenia are associated with abnormal hyperactivity in the left temporo-parietal junction (TPJ) and abnormal connectivity between frontal and temporal areas. Recent findings suggest that fronto-temporal transcranial Direct Current stimulation (tDCS) with the cathode placed over the left TPJ and the anode over the left prefrontal cortex can alleviate treatment-resistant AVH in patients with schizophrenia. However, brain correlates of the AVH reduction are unclear. Here, we investigated the effect of tDCS on the resting-state functional connectivity (rs-FC) of the left TPJ. Twenty-three patients with schizophrenia and treatment-resistant AVH were randomly allocated to receive 10 sessions of active (2 mA, 20min) or sham tDCS (2 sessions/d for 5 d). We compared the rs-FC of the left TPJ between patients before and after they received active or sham tDCS. Relative to sham tDCS, active tDCS significantly reduced AVH as well as the negative symptoms. Active tDCS also reduced rs-FC of the left TPJ with the left anterior insula and the right inferior frontal gyrus and increased rs-FC of the left TPJ with the left angular gyrus, the left dorsolateral prefrontal cortex and the precuneus. The reduction of AVH severity was correlated with the reduction of the rs-FC between the left TPJ and the left anterior insula. These findings suggest that the reduction of AVH induced by tDCS is associated with a modulation of the rs-FC within an AVH-related brain network, including brain areas involved in inner speech production and monitoring.Key words: resting state, brain stimulation, fMRI, temporal cortex 相似文献
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Functional connectivity and information flow of the respiratory neural network in chronic obstructive pulmonary disease 下载免费PDF全文
Lianchun Yu Marine De Mazancourt Agathe Hess Fakhrul R. Ashadi Isabelle Klein Hervé Mal Maurice Courbage Laurence Mangin 《Human brain mapping》2016,37(8):2736-2754
Breathing involves a complex interplay between the brainstem automatic network and cortical voluntary command. How these brain regions communicate at rest or during inspiratory loading is unknown. This issue is crucial for several reasons: (i) increased respiratory loading is a major feature of several respiratory diseases, (ii) failure of the voluntary motor and cortical sensory processing drives is among the mechanisms that precede acute respiratory failure, (iii) several cerebral structures involved in responding to inspiratory loading participate in the perception of dyspnea, a distressing symptom in many disease. We studied functional connectivity and Granger causality of the respiratory network in controls and patients with chronic obstructive pulmonary disease (COPD), at rest and during inspiratory loading. Compared with those of controls, the motor cortex area of patients exhibited decreased connectivity with their contralateral counterparts and no connectivity with the brainstem. In the patients, the information flow was reversed at rest with the source of the network shifted from the medulla towards the motor cortex. During inspiratory loading, the system was overwhelmed and the motor cortex became the sink of the network. This major finding may help to understand why some patients with COPD are prone to acute respiratory failure. Network connectivity and causality were related to lung function and illness severity. We validated our connectivity and causality results with a mathematical model of neural network. Our findings suggest a new therapeutic strategy involving the modulation of brain activity to increase motor cortex functional connectivity and improve respiratory muscles performance in patients. Hum Brain Mapp 37:2736–2754, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. 相似文献
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Marine Forien Alice Combier Anaïs Gardette Elisabeth Palazzo Philippe Dieudé Sébastien Ottaviani 《Joint, bone, spine : revue du rhumatisme》2018,85(5):615-618
Objective
Ultrasound (US) seems a useful tool for diagnosis of calcium pyrophosphate (CPP) deposition (CPPD). We aimed to compare the performance of US and conventional radiography of the wrist for diagnosis of CPPD.Methods
Patients with CPP crystals identified in synovial fluid (SF) (knee, hip, shoulder, ankle or wrist) were consecutively included and compared to patients without CPP crystals in synovial fluid considered as controls. As recommended, we used the term chondrocalcinosis (CC) to assess imaging features suggesting CPPD. In all patients, US and radiographic assessment of CC of the wrists was performed by two distinct operators blinded each other (one operator by imaging modality). The two operators were blinded to clinical data, SF analysis and US or radiography findings.Results
We included 32 CPPD patients and 26 controls. Among CPPD patients, US revealed CC in 30 (93.7%) and radiography in 17 (53.1%) (P < 0.001). The sensitivity and specificity of US for the diagnosis of CPPD were 94% and 85%, respectively; the positive likelihood ratio (LR + ) was 6.1. The sensitivity and specificity of radiography were 53.1% and 100%, respectively. At joints level independently of SF analysis, US revealed CC in 35 joints without radiographic CC whereas X-rays showed CC in 3 joints without US CC. The κ coefficient between US and radiography for CC was moderate: 0.33 (0.171–0.408).Conclusion
Our study suggests that wrist US should be considered as a relevant tool for the diagnosis of CPPD, with higher sensitivity than radiography for detecting CPP deposits. 相似文献69.
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Bioaccumulation enables to integrate the ability of aquatic organisms to regulate metals and effects of water chemistry on metal bioavailability. Linking this process to biological responses offers thus promising lines of enquiry for protecting aquatic ecosystems. This study aims at characterizing the mechanisms involved in waterborne Cu bioaccumulation and assessing metal impact on digestive metabolism in an ecosystem engineer widely distributed in Europe, Gammarus pulex. The organism was exposed to several Cu concentrations (from 0.5 to 100?μg/L) in aquatic microcosms to establish kinetic parameters for the construction and comparison of two bioaccumulation models, i.e. the biodynamic and saturation models. Cu uptake was recorded in waters exhibiting various concentrations of Na, Mg and Ca at environmental levels to assess the influence of cationic composition on bioaccumulation. Then, the effect of increasing Cu in exposure media on the digestive metabolism of G. pulex was investigated by measuring enzymatic activities (β-glucosidase, N-acetyl-β-glucosaminidase, β-galactosidase). We showed that the saturation model is more suitable than the biodynamic model to describe Cu bioaccumulation in gammarids due to a maximal capacity of animals to accumulate the metal. Cationic composition of water affected insignificantly Cu uptake. All activities of tested enzymes decreased with increasing Cu in exposure media but with different degrees. High correlations were established between the inhibition of enzymatic activities and amounts of Cu bioaccumulated by gammarids. These biological responses could thus provide early-warming of Cu impact on aquatic biota. 相似文献