Publications by authors named "Garrec J"

Despite their burden, most congenital defects remain poorly understood, due to lack of knowledge of embryological mechanisms. Here, we identify Greb1l mutants as a mouse model of crisscross heart. Based on 3D quantifications of shape changes, we demonstrate that torsion of the atrioventricular canal occurs together with supero-inferior ventricles at E10.

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The Passerini-Smiles reactions of α-ketophosphonates with nitrophenols has been used as a platform to observe complex cascades involving multiple Smiles transfers coupled with phospha-Brook rearrangement. When using 4-nitrophenols a rare 1,3-Truce-Smiles rearrangement is observed leading to diarylacetamide derivatives. 2-Nitro-derivatives lead to a completely different reactivity pattern that may be explained by a nitro to nitroso conversion followed by a σ-π metathesis.

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The secreted factor Nodal, known as a major left determinant, is associated with severe heart defects. Yet, it has been unclear how it regulates asymmetric morphogenesis such as heart looping, which align cardiac chambers to establish the double blood circulation. Here, we report that Nodal is transiently active in precursors of the mouse heart tube poles, before looping.

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Herein, a direct C8-arylation reaction of 1-amidonaphthalenes is described. By using diaryliodonium salts as arylating agents, the palladium-catalyzed C-H activation reaction showed perfect C8 regioselectivity and a wide functional group tolerance. In most cases, the desired polyaromatic compounds were isolated in good to excellent yields.

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Patient education constitutes a relevant strategy to improve pain management. In the field of therapeutic patient education (TPE), we aimed 1) to assess pain impact in cancer patients, 2) to identify patients' educative needs in pain management, and 3) to refine research criteria for its future evaluation. Pain intensity, relief and interference were assessed in 75 cancer patients with unbalanced background pain.

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The reaction of ketene with hydroxyl radical is drawing growing attention, for it is found to constitute an important step during the combustion of hydrocarbon and oxygenated hydrocarbon fuels, e.g., acetylene, propyne, allene, acetone, gasoline, diesel, jet fuels, and biofuels.

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Extensive studies have shown how bilateral symmetry of the vertebrate embryo is broken during early development, resulting in a molecular left-right bias in the mesoderm. However, how this early asymmetry drives the asymmetric morphogenesis of visceral organs remains poorly understood. The heart provides a striking model of left-right asymmetric morphogenesis, undergoing rightward looping to shape an initially linear heart tube and align cardiac chambers.

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Pain, one of the most feared symptoms for patients with cancer, remains insufficiently alleviated and impairs quality of life. Therapeutic patient education (TPE) is a relevant approach to this problem while allowing patients to develop skills to better manage their pain. In the "Basse-Normandie" French region, the management of pain relies on two organized networks, thus allowing proximity and accessibility for all concerned.

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How left-right patterning drives asymmetric morphogenesis is unclear. Here, we have quantified shape changes during mouse heart looping, from 3D reconstructions by HREM. In combination with cell labelling and computer simulations, we propose a novel model of heart looping.

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In the field of cancer pain, therapeutic patient education (TPE) allows patients to develop skills to better manage their pain. In the Lower Normandy region of France, the management of pain is based on networking, thus allowing proximity and accessibility for all concerned. We have thus designed and initiated a broad five-stage research program that includes the following: (1) training for caregivers in TPE; (2) identifying the educational expectations of patients and their relatives with regard to cancer pain; (3) the design of a TPE program; (4) the evaluation of its quality; and (5) the evaluation of its effectiveness by comparative randomization.

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We present a novel route for the quick and easy synthesis of a broad range of β-lactams. The synthesis involves a [3+1] cyclization of amide dianions with diiodomethane. In contrast to the seminal work of Hirai et al.

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The room temperature dissociative recombination of ions formed in an acetone/argon plasma has been studied using the flowing afterglow Langmuir probe-mass spectrometer method. By changing the concentration of acetone density, it is possible to have a plasma dominated by different types of ions (fragments, adducts, and dimer ions). The application of these measurements to astrophysical plasmas is discussed.

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Although in flies the atypical cadherin Fat is an upstream regulator of Hippo signalling, the closest mammalian homologue, Fat4, has been shown to regulate tissue polarity rather than growth. Here we show in the mouse heart that Fat4 modulates Hippo signalling to restrict growth. Fat4 mutant myocardium is thicker, with increased cardiomyocyte size and proliferation, and this is mediated by an upregulation of the transcriptional activity of Yap1, an effector of the Hippo pathway.

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To identify cell-based decisions implicated in morphogenesis of the mammalian liver, we performed clonal analysis of hepatocytes/hepatoblasts in mouse liver development, using a knock-in allele of Hnf4a/laacZ This transgene randomly undergoes a low frequency of recombination that generates a functional lacZ gene that produces β-galactosidase in tissues in which Hnf4a is expressed. Two types of β-galactosidase-positive clones were found. Most have undergone three to eight cell divisions and result from independent events (Luria-Delbrück fluctuation test); we calculate that they arose between E8.

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Introduction: Controversy exists regarding the treatment of infants with symptomatic nasolacrimal duct obstruction. One philosophy advocates "early" nasolacrimal duct probing, generally in the office - a relatively common approach in France, while others prefer to wait until the age of 12 months to offer a procedure under general anesthesia. The goal of this study is to report results of immediate office probing for congenital nasolacrimal duct obstruction (CNLDO) under age 1 year in terms of efficacy and cost.

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Nanoparticles formed within an ablation plume produced by the impact of a nanosecond laser pulse on the surface of an aluminum target have been directly measured using small-angle x-ray scattering. The target was immersed in an oxygen-nitrogen gas mixture at atmospheric pressure with the O_{2}/N_{2} ratio being precisely controlled. The results for an increasing oxygen content reveal remarkable effects on the morphology of the generated particles, which include a decrease in the particle volume but a marked increase in its surface ruggedness.

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X-ray photoelectron spectroscopy (XPS) is a very efficient and still progressing surface analysis technique. However, when applied to nano-objects, this technique faces drawbacks due to interactions with the substrate and sample charging effects. We present a new experimental approach to XPS based on coupling soft X-ray synchrotron radiation with an in-vacuum beam of free nanoparticles, focused by an aerodynamic lens system.

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The primary cilium is a small sensory organelle that is required for different aspects of embryonic development, including the formation of the heart. The structure and composition of cilia have been extensively studied, so that several markers of primary cilia have now been identified. However, the role of cilia in specific cell types remains poorly understood.

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Insights into the mechanisms of development of the mammalian four-chambered heart are based on biological observations at organ, tissue, cell, and molecular levels, but the full integration of these experimental data awaits a systems biology approach. Such an approach can be employed to formulate and test conceptual models in a computational simulation. To illustrate how this can be applied to heart development, we used the process of trabeculation, which is the formation of muscular strands during chamber development.

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Oxidatively generated tandem lesions such as G[8-5m]T pose a potent threat to genome integrity. Direct experimental studies of the kinetics and thermodynamics of a specific lesion within DNA are very challenging, mostly due to the variety of products that can be formed in oxidative conditions. Dinucleoside monophosphates (DM) involving only the reactive nucleobases in water represent appealing alternative models on which most physical chemistry and structural techniques can be applied.

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Lipid peroxidation is a fundamental phenomenon in biology and medicine involved in a wide range of diseases. Some key microscopic aspects of this reaction in cell membranes are still poorly studied. In particular, it is commonly accepted that the propagation of the radical reaction in lipid bilayers is hampered by the rapid diffusion of peroxyl intermediates toward the water interface, that is, out of the reaction region.

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The doppel (Dpl) and prion (PrP) proteins share a very similar fold (three helices and two short β-strands), while they differ significantly in sequence (only 25% homologous) and in disease-related β-rich conformations that occur for PrP only. In a previous study [Baillod, P., et al.

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Using molecular dynamics simulations, we show that the prion protein (PrP) exhibits a dual behavior, with two possible transition routes, upon protonation of H187 around pH 4.5, which mimics specific conditions encountered in endosomes. Our results suggest a picture in which the protonated imidazole ring of H187 experiences an electrostatic repulsion with the nearby guanidinium group of R136, to which the system responds by pushing either H187 or R136 sidechains away from their native cavities.

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Article Synopsis
  • Research in developmental biology needs effective tools to analyze images of developing tissues, as current methods struggle due to complexities in image acquisition.
  • The paper introduces an automated framework using partial differential equations to accurately segment 3D microscopy images of densely packed tissues.
  • This method has been successfully applied to study mouse heart development, yielding valuable quantitative and qualitative insights into cellular processes and tissue organization.
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Article Synopsis
  • Naturally occurring DNA damage, specifically the G[8-5]C cross-link lesion, is significant due to its high mutagenicity, despite being rare.
  • Hybrid Car-Parrinello molecular dynamics simulations were used to investigate the cyclization process of this lesion, revealing its activation free energy to be about 12.4 kcal/mol, which is higher than similar lesions.
  • The study found that the reactivity order of DNA bases changes in a solvated environment, indicating the impact of the surrounding medium on the behavior of the DNA lesions.
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