Institution
French Institute of Health and Medical Research
Government•Paris, France•
About: French Institute of Health and Medical Research is a government organization based out in Paris, France. It is known for research contribution in the topics: Population & Receptor. The organization has 109367 authors who have published 174236 publications receiving 8365503 citations.
Topics: Population, Receptor, Gene, Immune system, Antigen
Papers published on a yearly basis
Papers
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TL;DR: It is demonstrated that stimulus convergence in the auditory cortex is necessary for associative fear learning to complex tones, define the circuit elements mediating this convergence and suggest that layer-1-mediated disinhibition is an important mechanism underlying learning and information processing in neocortical circuits.
Abstract: Learning causes a change in how information is processed by neuronal circuits. Whereas synaptic plasticity, an important cellular mechanism, has been studied in great detail, we know much less about how learning is implemented at the level of neuronal circuits and, in particular, how interactions between distinct types of neurons within local networks contribute to the process of learning. Here we show that acquisition of associative fear memories depends on the recruitment of a disinhibitory microcircuit in the mouse auditory cortex. Fear-conditioning-associated disinhibition in auditory cortex is driven by foot-shock-mediated cholinergic activation of layer 1 interneurons, in turn generating inhibition of layer 2/3 parvalbumin-positive interneurons. Importantly, pharmacological or optogenetic block of pyramidal neuron disinhibition abolishes fear learning. Together, these data demonstrate that stimulus convergence in the auditory cortex is necessary for associative fear learning to complex tones, define the circuit elements mediating this convergence and suggest that layer-1-mediated disinhibition is an important mechanism underlying learning and information processing in neocortical circuits.
766 citations
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Yale University1, University of Lyon2, French Institute of Health and Medical Research3, University of Notre Dame4, Babeș-Bolyai University5, Max Planck Society6, Valparaiso University7, Netherlands Institute for Neuroscience8, University of Oxford9, McGill University10, Washington University in St. Louis11
TL;DR: The directed and weighted G29 × 91 connectivity matrix for the macaque will be valuable for comparison with connectivity analyses in other species, including humans, and inform future modeling studies that explore the regularities of cortical networks.
Abstract: Retrograde tracer injections in 29 of the 91 areas of the macaque cerebral cortex revealed 1,615 interareal pathways, a third of which have not previously been reported. A weight index (extrinsic fraction of labeled neurons [FLNe]) was determined for each area-to-area pathway. Newly found projections were weaker on average compared with the known projections; nevertheless, the 2 sets of pathways had extensively overlapping weight distributions. Repeat injections across individuals revealed modest FLNe variability given the range of FLNe values (standard deviation <1 log unit, range 5 log units). The connectivity profile for each area conformed to a lognormal distribution, where a majority of projections are moderate or weak in strength. In the G29 × 29 interareal subgraph, two-thirds of the connections that can exist do exist. Analysis of the smallest set of areas that collects links from all 91 nodes of the G29 × 91 subgraph (dominating set analysis) confirms the dense (66%) structure of the cortical matrix. The G29 × 29 subgraph suggests an unexpectedly high incidence of unidirectional links. The directed and weighted G29 × 91 connectivity matrix for the macaque will be valuable for comparison with connectivity analyses in other species, including humans. It will also inform future modeling studies that explore the regularities of cortical networks.
766 citations
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TL;DR: Two redundant parallel pathways may lead to chromatin processing during apoptosis, including one which involves Apaf-1 and caspases, as well as CAD, and leads to oligonucleosomal DNA fragmentation and advanced chromatin condensation and the other which is caspase-independent.
Abstract: Apaf-1−/− or caspase-3−/− cells treated with a variety of apoptosis inducers manifest apoptosis-associated alterations including the translocation of apoptosis-inducing factor (AIF) from mitochondria to nuclei, large scale DNA fragmentation, and initial chromatin condensation (stage I). However, when compared with normal control cells, Apaf-1−/− or caspase-3−/− cells fail to exhibit oligonucleosomal chromatin digestion and a more advanced pattern of chromatin condensation (stage II). Microinjection of such cells with recombinant AIF only causes peripheral chromatin condensation (stage I), whereas microinjection with activated caspase-3 or its downstream target caspase-activated DNAse (CAD) causes a more pronounced type of chromatin condensation (stage II). Similarly, when added to purified HeLa nuclei, AIF causes stage I chromatin condensation and large-scale DNA fragmentation, whereas CAD induces stage II chromatin condensation and oligonucleosomal DNA degradation. Furthermore, in a cell-free system, concomitant neutralization of AIF and CAD is required to suppress the nuclear DNA loss caused by cytoplasmic extracts from apoptotic wild-type cells. In contrast, AIF depletion alone suffices to suppress the nuclear DNA loss contained in extracts from apoptotic Apaf-1−/− or caspase-3−/− cells. As a result, at least two redundant parallel pathways may lead to chromatin processing during apoptosis. One of these pathways involves Apaf-1 and caspases, as well as CAD, and leads to oligonucleosomal DNA fragmentation and advanced chromatin condensation. The other pathway, which is caspase-independent, involves AIF and leads to large-scale DNA fragmentation and peripheral chromatin condensation.
765 citations
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TL;DR: The prevalence rate of infertility in France was found to be 14.1%, indicating that one woman out of seven in France will consult a doctor for an infertility problem during her reproductive life, and the main causes of female infertility were ovulation disorders and tubal damage.
Abstract: To estimate the prevalence and main causes of infertility, a multicentre survey was conducted over 1 year (July 1988-June 1989) in three regions of France. All the 1686 couples in these regions, who consulted a practitioner for primary or secondary infertility during this period, were included in the investigation. The prevalence rate of infertility was found to be 14.1%, indicating that one woman out of seven in France will consult a doctor for an infertility problem during her reproductive life. The main causes of female infertility were ovulation disorders (32%) and tubal damage (26%), and of male infertility oligo-terato-asthenozoospermia (21%), asthenozoospermia (17%), teratozoospermia (10%) and azoospermia (9%). Infertility was also found to be caused by disorders in both the male and female partners together; thus in 39% of cases both the man and woman presented with disorders. The woman alone was responsible for infertility in one-third of cases and the man alone in one-fifth. Unexplained infertility was found in 8% of the couples surveyed.
764 citations
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TL;DR: A new diagnostic indicator of FDG PET scan abnormality, based on age-adjusted t statistics and an automated voxel-based procedure, is presented and validated in a large data set comprising 110 normal controls and 395 patients with probable Alzheimer's disease (AD) that were studied in eight participating centers as discussed by the authors.
764 citations
Authors
Showing all 109539 results
Name | H-index | Papers | Citations |
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Guido Kroemer | 236 | 1404 | 246571 |
Pierre Chambon | 211 | 884 | 161565 |
Peer Bork | 206 | 697 | 245427 |
Ronald M. Evans | 199 | 708 | 166722 |
Raymond J. Dolan | 196 | 919 | 138540 |
Matthew Meyerson | 194 | 553 | 243726 |
Charles A. Dinarello | 190 | 1058 | 139668 |
Julie E. Buring | 186 | 950 | 132967 |
Tadamitsu Kishimoto | 181 | 1067 | 130860 |
Didier Raoult | 173 | 3267 | 153016 |
Giuseppe Remuzzi | 172 | 1226 | 160440 |
Zena Werb | 168 | 473 | 122629 |
Nahum Sonenberg | 167 | 647 | 104053 |
Philippe Froguel | 166 | 820 | 118816 |
Gordon J. Freeman | 164 | 579 | 105193 |