Delayed upregulation of the neuronal chloride extruder KCC2 underlies the progressive shift in GABA signaling polarity during development. Conversely, KCC2 downregulation is observed in a variety of neurological and psychiatric disorders often associated with cognitive impairment. Reduced KCC2 expression and function in mature networks may disrupt GABA signaling and promote anomalous network activities underlying these disorders.
View Article and Find Full Text PDFThis paper presents a prototype for the visualization of food-drug interactions implemented in the MIAM project, whose objective is to develop methods for the extraction and representation of these interactions and to make them available in the Thériaque database. The prototype provides users with a graphical visualization showing the hierarchies of drugs and foods in front of each other and the links between them representing the existing interactions as well as additional details about them, including the number of articles reporting the interaction. The prototype is interactive in the following ways: hierarchies can be easily folded and unfolded, a filter can be applied to view only certain types of interactions, and details about a given interaction are displayed when the mouse is moved over the corresponding link.
View Article and Find Full Text PDFControl of locomotion relies on motor loops conveying modulatory signals between brainstem and spinal motor circuits. We investigated the steering control of the brainstem reticular formation over the spinal locomotor networks using isolated brainstem-spinal cord preparations of male and female neonatal rats. First, we performed patch-clamp recordings of identified reticulospinal cells during episodes of fictive locomotion.
View Article and Find Full Text PDFThe postsynaptic proteome of excitatory synapses comprises ~1,000 highly conserved proteins that control the behavioral repertoire, and mutations disrupting their function cause >130 brain diseases. Here, we document the composition of postsynaptic proteomes in human neocortical regions and integrate it with genetic, functional and structural magnetic resonance imaging, positron emission tomography imaging, and behavioral data. Neocortical regions show signatures of expression of individual proteins, protein complexes, biochemical and metabolic pathways.
View Article and Find Full Text PDFEur J Clin Microbiol Infect Dis
December 2017
Dengue virus is endemic in French Guiana with occurrence of cyclical outbreaks. There is a need for rapid tests allowing dengue laboratory diagnosis in healthcare centers scattered throughout this wide Amazonian territory. Our objective was to evaluate the real-life performance of the SD BIOLINE Dengue Duo (IgG/IgM + NS1 Ag) rapid test (RDT) during the 2012-2013 dengue epidemics.
View Article and Find Full Text PDFThe structure and function of spines and excitatory synapses are under the dynamic control of multiple signalling networks. Although tyrosine phosphorylation is involved, its regulation and importance are not well understood. Here we study the role of Pyk2, a non-receptor calcium-dependent protein-tyrosine kinase highly expressed in the hippocampus.
View Article and Find Full Text PDFObjectives: Sickle cell disease (SCD) is the leading genetic disease in French Guiana, reflecting the predominantly African ancestry of the Guianese population. Our purpose was to characterize the genetic modulators of SCD in order to retrace the origin of the population in light of the slave trade.
Methods: We have studied the sickle cell genotype, the βS haplotypes, the alpha and beta thalassemia and the UGT1A1 promoter polymorphisms in 224 Guianese patients with SCD.
This study investigated the clinical epidemiology and resistance mechanisms of Acinetobacter baumannii and characterised the clonal diversity of carbapenem-resistant A. baumannii (CRAB) during an ICU-associated outbreak at Cayenne Hospital, French Guiana. All non-duplicate A.
View Article and Find Full Text PDFAlthough the basolateral amygdala (BLA) is known to play a critical role in the formation of memories of both positive and negative valence, the coding and routing of valence-related information is poorly understood. Here, we recorded BLA neurons during the retrieval of associative memories and used optogenetic-mediated phototagging to identify populations of neurons that synapse in the nucleus accumbens (NAc), the central amygdala (CeA), or ventral hippocampus (vHPC). We found that despite heterogeneous neural responses within each population, the proportions of BLA-NAc neurons excited by reward predictive cues and of BLA-CeA neurons excited by aversion predictive cues were higher than within the entire BLA.
View Article and Find Full Text PDFIntroduction: The frequency, the clinical characteristics, and the prognosis of dengue is highly variable. Dengue fever is associated with a range of neurological manifestations. The objective of the present study was to determine the incidence of neurological signs and their predictive factors using data from cases of dengue seen and followed in Cayenne Hospital during the Dengue 2 epidemic in 2013.
View Article and Find Full Text PDFBackground: Synapses are fundamental components of brain circuits and are disrupted in over 100 neurological and psychiatric diseases. The synapse proteome is physically organized into multiprotein complexes and polygenic mutations converge on postsynaptic complexes in schizophrenia, autism and intellectual disability. Directly characterising human synapses and their multiprotein complexes from post-mortem tissue is essential to understanding disease mechanisms.
View Article and Find Full Text PDFWe compared the neutralization sensitivity of early/transmitted HIV-1 variants from patients infected by subtype B viruses at 3 periods of the epidemic (1987-1991, 1996-2000, 2006-2010). Infectious pseudotyped viruses expressing envelope glycoproteins representative of the viral quasi-species infecting each patient were tested for sensitivity to neutralization by pools of sera from HIV-1 chronically infected patients and by an updated panel of 13 human monoclonal neutralizing antibodies (HuMoNAbs). A progressive significantly enhanced resistance to neutralization was observed over calendar time, by both human sera and most of the HuMoNAbs tested (b12, VRC01, VRC03, NIH45-46(G54W), PG9, PG16, PGT121, PGT128, PGT145).
View Article and Find Full Text PDFStudies of the kinetics of biochemical reactions, especially of folding of proteins and RNA, are important for understanding the function of biomolecules and processes in live cells. Many biochemical reactions occur rapidly and thus need to be triggered on very short time scales for their kinetics to be studied, which is often accomplished by mixing in a turbulent flow. More rapid and sample-efficient mixing is achieved in laminar flow in a microfluidic device, in which the sample is two-dimensionally (2D) focused to a thin sheet.
View Article and Find Full Text PDFEchinococcus vogeli infection in a hunter from the rain forest of French Guiana was confirmed by imaging and mitochondrial DNA sequence analysis. Serologic examination showed typical patterns for both alveolar and cystic echinococcosis. Polycystic echinococcis caused by E.
View Article and Find Full Text PDFIn this video, we show the use of a pneumatic capillary gun for the accurate biolistic delivery of reagents into live tissue. We use the procedure to perturb gene expression patterns in selected segments of leech embryos, leaving the untreated segments as internal controls. The pneumatic capillary gun can be used to reach internal layers of cells at early stages of development without opening the specimen.
View Article and Find Full Text PDFWe describe the design, fabrication, and operation of two types of flow cytometers based on microfluidic devices made of a single cast of poly(dimethylsiloxane). The stream of particles or cells injected into the devices is hydrodynamically focused in both transverse and lateral directions, has a uniform velocity, and has adjustable diameter and shape. The cytometry system built around the first microfluidic device has fluorescence detection accuracy comparable with that of a commercial flow cytometer and can analyze as many as 17 000 particles/s.
View Article and Find Full Text PDFWe report experiments on mixing of a passively advected fluorescent dye in a low Reynolds number flow in a microscopic channel. The channel is a chain of repeating segments with a custom designed profile that generates a steady three-dimensional flow with stretching and folding, and chaotic mixing. A few statistical characteristics of mixing in the flow are studied and are all found to agree with theoretical and experimental results for the flows in the Batchelor regime of mixing that are chaotic in time.
View Article and Find Full Text PDFForensic Sci Int
November 1999
Seric carbohydrate-deficient transferrin (CDT) is a biochemical marker of chronic alcohol abuse. Assessment of the influence of factors likely to modify CDT concentration is necessary to justify its use in the analysis of post-mortem blood samples. Hemolysis, site of collection and storage were tested.
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