Effect of Nanostructuring on the Thermoelectric Properties of β-FeSi2

Nanostructured β-FeSi2 and β-Fe0.95Co0.05Si2 specimens with a relative density of up to 95% were synthesized by combining a top-down approach and spark plasma sintering. The thermoelectric properties of a 50 nm crystallite size β-FeSi2 sample were compared to those of an annealed one, and for the former a strong decrease in lattice thermal conductivity and an upshift of the maximum Seebeck’s coefficient were shown, resulting in an improvement of the figure of merit by a factor of 1.7 at 670 K. For β-Fe0.95Co0.05Si2, one observes that the figure of merit is increased by a factor of 1.2 at 723 K between long time annealed and nanostructured samples mainly due to an increase in the phonon scattering and an increase in the point defects. This results in both a decrease in the thermal conductivity to 3.95 W/mK at 330 K and an increase in the power factor to 0.63 mW/mK2 at 723 K

Impact of graphite foil rolling on the thermal field homogeneity of spark plasma sintering

International audienceHeating and thermal gradients are important parameters in Spark Plasma Sintering (SPS) affecting densification, structure and microstructure of materials. Controlling those parameters requires advanced Joule heating simulations. The key aspect of these models is the identification of the electrical and thermal contact resistances (ECR and TCR) in the SPS tooling. The latter have a high importance to explain the experimental temperature field. The ECRs and TCRs have already been determinated in a previous work by simulating the experimental thermal field. However, these previous studies consider rolled graphite foil placed between the die and punches. ECRs and TCRs have been recalibrated to consider a “no rolling graphite foil”, using SPS experiments equipped with several temperature measurements points. Those new tests shows that the previous model overestimated the temperature of the punches and sample up to 400°C when applied to a configuration with “no rolling graphite foil”. This recalibration also demonstrates it is necessary to divide the foil ECR by 2 and the TCR by 10 to obtain a predictive simulation of the thermal field. This study also shows that the use of a “no rolling graphite foil” reduces significantly the heterogeneity of thermal field

A phase I/II feasibility vaccine study by autologous leukemic apoptotic corpse-pulsed dendritic cells for elderly AML patients

International audienceThis was a phase I/II study testing the feasibility of a vaccine by autologous leukemic apoptotic corpse-pulsed dendritic cells (DC) in elderly acute myeloid leukemia (AML) patients in first or second complete remission. Pulsed DC were administered at doses of 9 × 106 subcutaneously (1 mL) and 1 × 106 intra-dermally (0.1 mL). Five doses of vaccine were planned on days +1 + 7 + 14 + 21 and +35. Five DC-vaccines were produced and injected for all five patients included in the study. No severe adverse event was documented. Larger Phase 2 studies are now required to precise the role of DC-vaccines with leukemic apoptotic bodies in older as well as younger AML populations

Antibody response after 2 and 3 doses of SARS-CoV-2 mRNA vaccine in allogeneic hematopoietic cell transplant recipients

International audienceThree reports address the protection of the vulnerable population of patients with hematologic malignancies in the face of the ongoing COVID pandemic. The reports suggest that some patients who fail to mount a B-cell response to vaccine may nevertheless have protective T cell responses. As a group, these reports suggest that patients should continue to be immunized with additional doses to attempt to improve immune response but that they need to maintain the precautions recommended for the unvaccinated

Diagnosis and prognosis are comforted by integrated assessment of next-generation sequencing in chronic myeloid malignancies. A real-life study

International audienceNext generation sequencing (NGS) investigates for somatic mutations. The utility of incorporating routine sequencing to guide diagnosis and therapeutic decisions remains challenging. We report an observational multicentric study that aimed to assess the impact of somatic mutations testing by NGS in a real-life setting of chronic myeloid malignancies (CMM). A total of 177 patients were enrolled, partitioned in two overlapping groups. In group A (N=94), the indication was to search for clonal hematopoiesis (CH), in a context of suspected myelodysplastic syndrome or myeloproliferative neoplasia. In group B (N=95), the theranostic impact of somatic mutations was studied. A panel of 34 genes was applied on DNA extracted from blood or bone marrow samples. Within group A, the detection of CH comforted the diagnosis of CMM for 31 patients while absence of CH ruled out the suspected diagnosis in 47 patients. Within group B, NGS identified prognostic somatic mutations in 32 patients, with a therapeutic impact in 18 cases. The use of NGS in daily practice was found here to be useful for an integrated final diagnosis in 83% of the patients through the presence or absence of somatic mutations. Moreover, exploration for somatic mutations had a prognostic impact that led to treatment modification in 19% of the cases. This study outlines the fact that adequate prescription of these new investigations may have a significant positive medico-economic impact by allowing appropriate management of the patients

Sequential allogeneic hematopoietic stem cell transplantation for active refractory/relapsed myeloid malignancies: results of a reduced-intensity conditioning preceded by clofarabine and cytosine arabinoside, a retrospective study on behalf of the SFGM-TC

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Suspicious liver nodule in chronic liver disease: Usefulness of a second biopsy

IF 2.115 (2017)International audiencePurposeTo assess the usefulness of a second biopsy when the first one was inconclusive in patients with a liver nodule found during the follow-up for chronic liver disease.Materials and methodsAmong 381 patients (544 nodules) included in a prospective study designed to evaluate the accuracy of imaging for the diagnosis of small hepatocellular carcinoma (HCC) in chronic liver disease, 254 nodules were biopsied. The following histological results were considered as conclusive: HCC, dysplastic or regenerative nodule, and other identified tumors (benign or malignant). For nodules with inconclusive results (e.g. fibrosis or no definite focal lesion), a second biopsy was suggested, but was not mandatory.ResultsA total of 242 patients (194 men, 48 women; mean age, 61.9 ± 9.5 [SD]; range: 40.2–89.0 years) with 254 nodules underwent a first biopsy. Mean nodule diameter was 19.2 ± 5.4 mm (range: 10–33 mm). The first biopsy was conclusive in 189/254 nodules (74.4%): 157 HCCs (83.1%), 11 regenerative nodules (5.8%), 10 dysplastic nodules (5.3%), 3 cholangiocarcinomas (1.6%), and 8 other tumors (4.2%). Among the 65 nodules for which the first biopsy was inconclusive, a second biopsy was performed for 17 nodules in 16 patients within 6 months of the first one. It was conclusive in 13/17 nodules (76.5%): 10 HCCs (76.9%), 2 dysplastic nodules (15.4%), and 1 other tumor (7.7%). In 4/17 nodules (23.5%), no definitive diagnosis could be provided.ConclusionThe diagnostic yield of a second biopsy of a suspicious lesion suggestive of HCC in chronic liver disease is not decreased compared to the first one. Repeated biopsy after a first negative one could be an alternative option to the follow-up of patients with chronic liver disease

Comparison of Two Reduced Intensity Conditioning Regimens (Baltimore with Clofarabine vs Thiotepa-Busulfan-Fludarabine) in Adults Receiving Peripheral Blood Stem Cell Haploidentical Transplantation for Myeloid Malignancies: A Retrospective Study of the SFGM-TC

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