Publications by authors named "Noemie Ravalet"

Acute myeloid leukemia (AML) is a heterogeneous group of hematopoietic cancers. Cytokines play an important role in the regulation of normal and pathologic hematopoiesis. A pro-inflammatory state, described in hematopoietic malignancies, may participate in clonal selection.

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Childhood immune thrombocytopenia (ITP) is a rare autoimmune disorder characterized by isolated thrombocytopenia. Prolonged ITP (persistent and chronic) leads to a reduced quality of life for children in many domains. To provide optimal support for children, with ITP, it is important to be able to predict those who will develop prolonged ITP.

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Chronic myelomonocytic leukemia (CMML) is a myelodysplastic/myeloproliferative neoplasm characterized by the infiltration of blood and bone marrow by immature monocytes, in which extra-hematopoietic localization is uncommon. We report the case of a 69-year-old-man with highly likely ectopic brain CMML involvement by MRI. Without the possibility of cerebral biopsy and with a negative infectious disease assessment, high-dose cytarabine-based chemotherapy was successfully administered.

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Article Synopsis
  • Aging leads to changes in bone marrow (BM) and blood plasma cytokine levels, indicating a process called inflammaging.
  • In a study with 94 healthy volunteers, researchers found that certain cytokines increased or decreased with age, highlighting the complex relationship between aging and immune response.
  • The findings may help in understanding conditions linked to aging, such as myeloid malignancies and inflammatory diseases, by providing reference values for blood and bone marrow cytokine levels.
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The aim of this study was to characterize the functional expression of sodium-calcium exchangers on AFT024 cell line, a murine model of mesenchymal stem/stromal cells (MSCs) supporting human primitive hematopoiesis. All current-clamp and voltage-clamp experiments were performed using the perforated patch whole-cell recording technique with amphotericin B. The membrane potential of -14 mV shifted to -35 mV when lowering the external sodium concentration to 0.

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DNA methylation, a major biological process regulating the transcription, contributes to the pathophysiology of hematologic malignancies, and hypomethylating agents are commonly used to treat myelodysplastic syndromes (MDS) and acute myeloid leukemias (AML). In these diseases, bone marrow mesenchymal stromal cells (MSCs) play a key supportive role through the production of various signals and interactions. The DNA methylation status of MSCs, likely to reflect their functionality, might be relevant to understand their contribution to the pathophysiology of these diseases.

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(1) Background: The impact of occupational exposure to high doses of pesticides on hematologic disorders is widely studied. Yet, lifelong exposure to low doses of pesticides, and more particularly their cocktail effect, although poorly known, could also participate to the development of such hematological diseases as myelodysplastic syndrome (MDS) in elderly patients. (2) Methods: In this study, a cocktail of seven pesticides frequently present in water and food (maneb, mancozeb, iprodione, imazalil, chlorpyrifos ethyl, diazinon and dimethoate), as determined by the European Food Safety Authority, were selected.

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Background: In ineffective erythropoiesis, hepcidin synthesis is suppressed by erythroid regulators, namely erythroferrone and growth differentiation factor-15. For the first time, the hypothesis that iron overload in megaloblastic anemia may be related to ineffective erythropoiesis is explored by describing the kinetics of hepcidin, erythroferrone, and growth differentiation factor-15 levels in a patient diagnosed with megaloblastic anemia associated with iron overload.

Case Presentation: An 81-year-old Caucasian male was admitted for fatigue.

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The incidence of myelodysplastic syndrome increases with aging and the early diagnosis enables optimal care of these diseases. The DxH 800 hematology analyzer measures and calculates 126 cytological parameters, but only 23 are used for routine CBC assessment. The goal of this study was to use the 103 unexploited "research parameters" to develop an algorithm allowing for an early detection of subclinical MDS patients by triggering morphological analysis.

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The impact of pesticides on health is a major public health concern. A higher risk to develop chronic lymphoid malignancies has been demonstrated to be associated with occupational pesticide exposure (OPE). By contrast, little is known of the impact of OPE on the occurrence of myeloid malignancies especially acute myeloid leukemia (AML).

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Article Synopsis
  • The bone marrow microenvironment is essential in the growth and progression of acute myeloid leukemia (AML), influencing how leukemia cells maintain themselves.
  • Intracellular reactive oxygen species (ROS) and the enzyme GPx-3 are key players in regulating the biology of leukemia-initiating cells, with direct cell contact between mesenchymal stromal cells (MSCs) and AML cells showing significant effects on ROS levels and cell proliferation.
  • The study indicates that MSCs and AML cells engage in a reciprocal relationship that affects oxidative metabolism, where GPx-3 expression is critical in controlling leukemogenesis.
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Low reactive oxygen species (ROS) levels are well-established characteristics of mouse hematopoietic stem cells (HSCs). However, little is known about these levels in human HSCs. This study aimed at quantifying ROS levels in human CD34 CD38 and CD34 CD38 human progenitors from bone marrow, cord blood and cells mobilized for autologous HSC transplantation.

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Clonal hematopoiesis (CH) of indeterminate potential has been described in blood samples from large series of patients. Its prevalence and consequences are still not well understood because sequencing methods vary and because most studies were performed in cohorts comprising individuals with nonhematologic diseases. Here, we investigated the frequency of CH in 82 paired bone marrow and blood samples from carefully selected healthy adult volunteers.

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Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal stem cell disorders with an inherent tendency for transformation in secondary acute myeloid leukemia. This study focused on the redox metabolism of bone marrow (BM) cells from 97 patients compared with 25 healthy controls. The level of reactive oxygen species (ROS) was quantified by flow cytometry in BM cell subsets as well as the expression level of 28 transcripts encoding for major enzymes involved in the antioxidant cellular response.

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Article Synopsis
  • The original article left out some acknowledgments regarding funding.
  • The missing information stated that the research was supported by grants to KZ from UL and L-CNRS.
  • The correction has been made in both the PDF and HTML versions of the article.
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Article Synopsis
  • * Researchers found that blocking gap junctions, which facilitate communication between BM-MSCs and leukemic cells, could alter these interactions and potentially reduce chemoresistance in AML.
  • * The gap junction disruptor carbenoxolone (CBX) showed promise as a treatment, demonstrating an ability to induce cell death in AML cells without harming normal progenitor cells, and enhancing the effectiveness of the chemotherapy drug cytarabine.
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Acute Myeloid Leukemia (AML) remains a therapeutic challenge and improvements in chemotherapy are needed. n-3 polyunsaturated fatty acids (PUFAs), present in fish oil (FO) at high concentrations, have antitumoral properties in various cancer models. We investigated the effects of two n-3 PUFAs, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), in AML cell lines and primary AML blasts.

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