Publications by authors named "Gueguen G"

The prognosis of children with acute myeloid leukemia (AML) has improved incrementally over the last few decades. However, at relapse, overall survival (OS) is approximately 40-50% and is even lower for patients with chemo-refractory disease. Effective and less toxic therapies are urgently needed for these children.

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Purpose Of Review: Despite higher remission and survival rates than observed in adults, children with acute myeloid leukemia (AML) still suffer unacceptably high rates of treatment failure and late toxicities. Ongoing work aims to improve these long-term outcomes through improvements in the utilization of current therapies, the incorporation of novel chemotherapy agents, and improved use of current or novel cellular and immunotherapeutic approaches. In this review, we highlight recent advances and contextualize them within this evolving landscape.

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Importance: Innovative anticancer therapies for children, adolescents, and young adults are regularly prescribed outside their marketing authorization or through compassionate use programs. However, no clinical data of these prescriptions is systematically collected.

Objectives: To measure the feasibility of the collection of clinical safety and efficacy data of compassionate and off-label innovative anticancer therapies, with adequate pharmacovigilance declaration to inform further use and development of these medicines.

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Introduction: To date, invasive fungal infections (IFIs) are still responsible for a high mortality rate in children managed for haematological malignancy. Although Candida and Aspergillus infections remain in the majority, emerging fungal infections are increasingly common. Children differ from adults in their pathology and treatment, as well as in their prior fungal colonisation and unique pharmacokinetics.

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The evolutionary success of parasitoid wasps, a highly diverse group of insects widely used in biocontrol, depends on a variety of life history strategies in conflict with those of their hosts [1]. Drosophila melanogaster is a natural host of parasitic wasps of the genus Leptopilina. Attack by L.

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It has been known for long that the fluctuation surface tension of membranes r, computed from the height fluctuation spectrum, is not equal to the bare surface tension σ, which is introduced in the theory either as a Lagrange multiplier to conserve the total membrane area or as an external constraint. In this work we relate these two surface tensions both analytically and numerically. They are also compared to the Laplace tension γ, and the mechanical frame tension τ.

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A model of lipid bilayers made of a mixture of two lipids with different average compositions on both leaflets, is developed. A Landau Hamiltonian describing the lipid-lipid interactions on each leaflet, with two lipidic fields ψ 1 and ψ 2, is coupled to a Helfrich one, accounting for the membrane elasticity, via both a local spontaneous curvature, which varies as C 0 + C 1(ψ 1 - ψ 2/2), and a bending modulus equal to κ 0 + κ 1(ψ 1 + ψ 2)/2. This model allows us to define curved patches as membrane domains where the asymmetry in composition, ψ 1 - ψ 2, is large, and thick and stiff patches where ψ 1 + ψ 2 is large.

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Background: The taxonomy of the species complex Bemisia tabaci is still an unresolved issue. Recently, phylogenetic analysis based on mtCOI identified 31 cryptic species. However, mitochondrial diversity is observed within these species, associated with distinct symbiotic bacterial communities forming associations, which here are called cytotypes.

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Polydnaviruses are mutualists of their parasitoid wasps and express genes in immune cells of their Lepidopteran hosts. Polydnaviral genomes carry multiple copies of viral ankyrins or vankyrins. Vankyrin proteins are homologous to IκB proteins, but lack sequences for regulated degradation.

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Analysis of natural host-parasite relationships reveals the evolutionary forces that shape the delicate and unique specificity characteristic of such interactions. The accessory long gland-reservoir complex of the wasp Leptopilina heterotoma (Figitidae) produces venom with virus-like particles. Upon delivery, venom components delay host larval development and completely block host immune responses.

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Article Synopsis
  • - Receptor tyrosine kinases (RTKs) are important targets for developing new cancer drugs, but most existing inhibitors work by blocking the main binding sites for ligands and substrates.
  • - The chemical SSR128129E (SSR) is a new type of RTK inhibitor that binds to a different site on the fibroblast growth factor receptor (FGFR), allowing it to inhibit signaling without interfering with the binding of its normal ligands.
  • - SSR shows potential for treating hard-to-target tumors and arthritis, demonstrating that orally-taken, allosteric RTK modulators could lead to better cancer treatment options.
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Wolbachia bacteria are ubiquitous intracellular bacteria of arthropods. Often considered reproductive parasites, they can benefit certain host species. We describe a new Wolbachia strain from Leptopilina victoriae, a Drosophila wasp.

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Viruses and virus-like particles (VLPs) of insect parasitoids modify host-parasite interactions. The Drosophila wasp, Leptopilina heterotoma, produce 300 nm spiked VLPs that bind to the host's blood cells via surface projections. L.

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Bemisia tabaci, an invasive pest that causes crop damage worldwide, is a highly differentiated species complex, divided into biotypes that have mainly been defined based on mitochondrial DNA sequences. Although endosymbionts can potentially induce population differentiation, specialization and indirect selection on mtDNA, studies have largely ignored these influential passengers in B. tabaci, despite as many as seven bacterial endosymbionts have been identified.

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Symbiotic relationships with bacteria are common within the Arthropoda, with interactions that substantially influence the biology of both partners. The symbionts' spatial distribution is essential for understanding key aspects of this relationship, such as bacterial transmission, phenotype, and dynamics. In this study, fluorescence in situ hybridization was used to localize five secondary symbionts from various populations and biotypes of the sweet potato whitefly Bemisia tabaci: Hamiltonella, Arsenophonus, Cardinium, Wolbachia, and Rickettsia.

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HLA-G is a major histocompatibility complex class Ib molecule whose constitutive tissue distribution is restricted mainly to trophoblast cells at the maternal-fetal interface during pregnancy. In this study, we demonstrated the ability of the soluble HLA-G1 (sHLA-G1) isoform to inhibit fibroblast growth factor-2 (FGF2)-induced capillary-like tubule formation. Using a rabbit corneal neovascularization model, we further showed that sHLA-G1 inhibits FGF2-induced angiogenesis in vivo.

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Introduction: We performed a prospective study of 12 intra-articular distal radial fractures. The fractures were treated with an anterior plate together with posterior pinning. The aim of the study was to examine whether it was technically feasible to fix such fractures using this technique and to assess the stability of the fixation at follow up.

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A previous study demonstrated that cross-desensitization experiments performed with the lysophosphatidic acid (LPA) analogues (R)- and (S)-N-palmitoyl-norleucinol 1-phosphate (PNPAs) inhibited LPA-induced platelet aggregation without any stereospecificity. Here we report opposite biological effects of the two enantiomers on mitogenesis of IMR-90 fibroblasts in relation to their respective metabolism. (R)PNPA was proliferative, while (S)PNPA induced apoptosis by specifically inhibiting phosphatidylcholine biosynthesis at the last step of the CDP-choline pathway controlled by cholinephosphotransferase.

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Purpose Of The Study: We analyzed retrospectively 30 Kudo non-constrained elbow prostheses to determine: 1) functional outcome and mobility, 2) frequency of loosening and any complications.

Material And Methods: From 1992 to 1998, 30 Kudo total elbow arthroplasties were performed in 29 patients, mean age 55 years. Mean follow-up was 36 months.

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From 1991 to 1998, 23 humeral fractures has been treated using the Orthofix external fixator. Average age of the patient was 42 y and average follow-up 55.5 m.

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Musculoskeletal disorders including arthralgia and myalgia are adverse effect common to all fluoroquinolones. We report a case of spontaneous rupture of the patellar ligament in a 37-year-old man participating in leisure sports which occurred one month after a three-week course of Ciprofloxacine(R). Several cases of tendon ruptures have been reported in the literature, including the patellar tendon.

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We report a case of carpal injury not previously described, associating three lesions of the carpus secondary to a hyperextension mechanism: fracture of the capitate, scapho-trapezio-trapezoid sprain and lunotriquetral ligament rupture. The patient was operated by percutaneous pinning after closed reduction. The capitate fracture was not fixed.

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Lysophosphatidic acid (1-acyl-sn-glycero-3-phosphate or LPA) is a phospholipid mediator displaying numerous and widespread biological activities and thought to act via G-protein-coupled receptors. Here we have studied the effects on human platelets of a number of LPA analogues, including two enantiomers of both N-palmitoyl-(L)-serine-3-phosphate ((L) and (D)NAPS for N-acyl-phosphoserine) and 2-(R)-N-palmitoyl-norleucinol-1-phosphate ((R) and (S)PNPA), cyclic analogues of 1-acyl-sn-glycero-3-phosphate (cPA) and of 1-O-hexadecyl-sn-glycero-3-phosphate (cAGP), sphingosine-1-phosphate (SPP), as well as two palmitoyl derivatives of dioxazaphosphocanes bearing either a P-H or a P-OH bond (DOXP-H and DOXP-OH, respectively). Nine of these compounds induced platelet aggregation with the following order of potency: SPP < cAGP < DOXP-OH < (L)NAPS = (D)NAPS < (R)PNPA = (S)PNPA < LPA < AGP, EC50 varying between 9.

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