Pierre-and-Marie-Curie University

About: Pierre-and-Marie-Curie University is a education organization based out in Paris, France. It is known for research contribution in the topics: Population & Raman spectroscopy. The organization has 34448 authors who have published 56139 publications receiving 2392398 citations.

Identification and characterization of a non-satellite cell muscle resident progenitor during postnatal development

Abstract: Satellite cells are resident myogenic progenitors in postnatal skeletal muscle involved in muscle postnatal growth and adult regenerative capacity. Here, we identify and describe a population of muscle-resident stem cells, which are located in the interstitium, that express the cell stress mediator PW1 but do not express other markers of muscle stem cells such as Pax7. PW1(+)/Pax7(-) interstitial cells (PICs) are myogenic in vitro and efficiently contribute to skeletal muscle regeneration in vivo as well as generating satellite cells and PICs. Whereas Pax7 mutant satellite cells show robust myogenic potential, Pax7 mutant PICs are unable to participate in myogenesis and accumulate during postnatal growth. Furthermore, we found that PICs are not derived from a satellite cell lineage. Taken together, our findings uncover a new and anatomically identifiable population of muscle progenitors and define a key role for Pax7 in a non-satellite cell population during postnatal muscle growth.

Wavelength-Multiplexed Quantum Networks with Ultrafast Frequency Combs

Abstract: Single-step fabrication of a multimode quantum resource from the parametric downconversion of femtosecond frequency combs is demonstrated. Each of the 511 possible bipartitions among ten spectral regions is shown to be entangled. Furthermore, an eigenmode decomposition reveals that eight independent quantum channels (qumodes) are subsumed within the comb.

Lateral organization of membrane proteins: tetraspanins spin their web.

Abstract: Despite high expression levels at the plasma membrane or in intracellular vesicles, tetraspanins remain among the most mysterious transmembrane molecules 20 years after their discovery. Several genetic studies in mammals and invertebrates have demonstrated key physiological roles for some of these tetraspanins, in particular in the immune response, sperm-egg fusion, photoreceptor function and the normal function of certain epithelia. Other studies have highlighted their ability to modulate cell migration and metastasis formation. Their role in the propagation of infectious agents has drawn recent attention, with evidence for HIV budding in tetraspanin-enriched plasma membrane domains. Infection of hepatocytic cells by two major pathogens, the hepatitis C virus and the malaria parasite, also requires the tetraspanin CD81. The function of tetraspanins is thought to be linked to their ability to associate with one another and a wealth of other integral proteins, thereby building up an interacting network or 'tetraspanin web'. On the basis of the biochemical dissection of the tetraspanin web and recent analysis of the dynamics of some of its constituents, we propose that tetraspanins tightly regulate transient interactions between a variety of molecules and as such favour the efficient assembly of specialized structures upon proper stimulation.

Immune and Stromal Classification of Colorectal Cancer Is Associated with Molecular Subtypes and Relevant for Precision Immunotherapy

Abstract: Purpose: The tumor microenvironment is formed by many distinct and interacting cell populations, and its composition may predict patient9s prognosis and response to therapies. Colorectal cancer (CRC) is a heterogeneous disease in which immune classifications and four consensus molecular subgroups (CMS) have been described. Our aim was to integrate the composition of the tumor microenvironment with the consensus molecular classification of CRC. Experimental design: We retrospectively analyzed the composition and the functional orientation of the immune, fibroblastic and angiogenic microenvironment of 1388 CRC tumors from three independent cohorts using transcriptomics. We validated our findings using immunohistochemistry. Results: We report that CRC molecular subgroups and microenvironmental signatures are highly correlated. Out of the four molecular subgroups, two highly express immune-specific genes. The good-prognosis microsatellite-instable-enriched subgroup (CMS1) is characterized by overexpression of genes specific to cytotoxic lymphocytes. In contrast, the poor-prognosis Mesenchymal subgroup (CMS4) expresses markers of lymphocytes and of cells of monocytic origin. The Mesenchymal subgroup also displays an angiogenic, inflammatory and immunosuppressive signature, a coordinated pattern that we also found in breast (n=254), ovarian (n=97), lung (n=80) and kidney (n=143) cancers. Pathological examination revealed that the Mesenchymal subtype is characterized by a high density of fibroblasts that likely produce the chemokines and cytokines which favor tumor-associated inflammation and support angiogenesis, resulting in a poor prognosis. In contrast, the Canonical (CMS2) and Metabolic (CMS3) subtypes with intermediate prognosis exhibit low immune and inflammatory signatures. Conclusions: The distinct immune orientations of the CRC molecular subtypes pave the way for tailored immunotherapies.

Total and young organic matter distributions in aggregates of silty cultivated soils

Abstract: Summary The distribution of organic matter in soil aggregates was investigated by fractionating aggregates and measuring carbon contents. The distribution of recently incorporated organic carbon was analyzed using 13C natural abundance. The soils of the experiment, which previously only had C3 vegetation, were cropped to maize, aC4 plant, for 6 or 23 years. Aggregate size distributions were determined for silty soils with different organic matter contents. Slaking-resistant macroaggregates were enriched in C as compared to dry-sieved macroaggregates or to microaggregates, and the C content increased with the size of aggregates. The δ13C value was used to calculate the amount of C3-derived and C4-derived organic carbon in the fractions. The larger carbon contents in stable macroaggregates were due to young C4-derived organic carbon (<6 or 23 years), and we concluded that young organic matter was responsible for macroaggregate stability.