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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+ CD38low and CD34+ CD38high human progenitors from bone marrow, cord blood and cells mobilized for autologous HSC transplantation. A specifically devised multiparameter flow cytometry method was used to quantify ROS levels (H2 DCFDA staining) in sub-populations of primary cells. Results were confirmed by assessing gene expression level of the ROS scavenger GPX3, a key determinant of HSC self-renewal, in sorted CD34+ CD38low and CD34+ CD38high cells. CD34+ CD38low cells from bone marrow and cord blood displayed significantly lower levels of ROS than CD34+ CD38high cells and other leukocytes. Moreover, the correlation between ROS and GPX3 expression was verified in sorted CD34+ CD38low and CD34+ CD38high cells. These results confirm, in human, data previously reported in mice. Moreover, the flow cytometry assay we developed could allow for a more precise enumeration of repopulating primitive progenitors in the course of HSC transplantation.

The prognostic significance of hypercalcemia in lymphoma has only been studied on small series to date. We conducted a retrospective, monocentric, matched-control study that aimed to compare the outcome of patients diagnosed with any histological subtype of lymphoma associated with hypercalcemia, at diagnosis or relapse, with a group of controls matched for histological and prognostic factors. Sixty-two and 118 comparable patients treated between 2000 and 2016 were included in hypercalcemia and control cohorts, respectively. Hypercalcemia was found mainly at diagnosis (71%) in higher-risk patients (prognosis scores ≥ 3, 76%) and those with diffuse large B cell lymphoma (67.7%), stage III/IV disease (91.9%), and elevated LDH (90.3%). Two-year progression-free survival (PFS) was shorter in the hypercalcemia than control cohort [30.1% (95% confidence interval (95% CI) 18.3–41.9) vs 63.9% (95% CI 5.1–72.7), p

The coexistence of dual hematological neoplasms is very rare. Sequential or synchronous neoplasms in hematology are an uncommon and complex clinical situation. The aim of the Hemo2 study was to describe the clinical characteristics and analyze the outcome of these patients. We performed a retrospective review of all patients diagnosed with sequential or synchronous hematological malignancies in the university hospital of Tours, between 2007 and 2018. We identified 49 patients in our study, with a prevalence of 0.89%. Sequential and synchronous combinations were found in 36 (73%) and 13 (27%) patients, respectively. One patient presented three sequential neoplasms. The median cumulative incidence was 6 years (95% CI 3–7). Among all neoplasms diagnosed (n = 99), we found 79 lymphoid neoplasms (LNs) (80%) and 20 myeloid neoplasms (MNs) (20%). Sex ratio was 1.88 with 65% of males and 35% of females. The most common LNs were Hodgkin lymphoma (n = 16; 16%) and multiple myeloma (n = 11; 11%). The most frequent MN was essential thrombocythemia (n = 5; 5%). The most common combination was Hodgkin lymphoma and follicular lymphoma in five (10%) patients. The overall survival from the first diagnosis (OS1) at 5 years was 82.4% (95% CI 72.1–94.3). The median overall survival from the second diagnosis (OS2) was 98 months (95% CI 44–NR) and 5-year OS2 was 58.7% (95% CI 45.5–75.7). Median progression-free survival from the second diagnosis (PFS) was 47 months (95% CI 27–NR) with 5-year PFS of 49% (95% CI 35.9–67). OS and PFS did not statistically differ between synchronous and sequential dual neoplasms. In this cohort, that the death relative risk (RR) was significantly lower if the second neoplasm appeared after more than 4 years following the first diagnosis (OR 0.37 (95% CI 0.16–0.90)). The Hemo2study confirmed the rarity of dual hematological neoplasms. In this cohort, HL and FL were the most frequent combinations. Our results may support that synchronous and sequential dual neoplasms bear the same prognosis. Further studies are needed to better characterize these uncommon clinical situations.

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 &ldquo, research parameters&rdquo, to develop an algorithm allowing for an early detection of subclinical MDS patients by triggering morphological analysis. Blood sample parameters from 101 MDS patients and 88 healthy volunteers were analyzed to identify the critical &ldquo, with: (i) the most significant differences between MDS patients and healthy volunteers, (ii) the best contributions to principal component analysis (PCA), first axis, and (iii) the best correlations with PCA, first two axes (cos2 &gt, 0.6). Ten critical &ldquo, of white blood cells were identified, allowing for the calculation of an MDS-likelihood score (MDS-LS), based on logistic regression. Automatic calculation of the MDS-LS is easily implementable on the middleware system of the DxH 800 to generate a flag for blood smear review, and possibly early detection of MDS patients in the general population.

Contexte : Développer le raisonnement est une nécessité dans la formation des professionnels de la santé. La formation par concordance (FpC) est une approche pédagogique qui place les apprenants dans des situations authentiques. Les questions posées sont celles que se posent les professionnels dans leur pratique et les réponses sont comparées à celles qu’ont données les membres d’un panel de référence. But : Décrire les variables dont il est nécessaire de tenir compte pour concevoir une FpC. Méthodes : Ces variables sont au nombre de six : 1) les buts de l’activité pédagogique ; 2) la nature de la tâche ; 3) le contenu et le niveau de complexité ; 4) le panel de référence ; 5) les rétroactions ; 6) l’environnement numérique d’apprentissage. Résultats : Les exemples illustrés dans cet article permettent de constater la versatilité de cette approche pour mettre l’accent sur les divers éléments critiques au raisonnement de diverses professions. Conclusion : Les exemples présentés illustrent comment il est possible de mettre au point des outils de FpC qui se prêtent à l’amélioration à chaque itération. Il est désormais possible d’imaginer qu’un jour cette approche à la formation fera partie importante de toute formation professionnelle.

INTRODUCTION Cytokines are involved in many processes, including hematopoiesis and inflammation. Aging is associated with the onset of clonal hematopoiesis (CH) of indeterminate potential, putatively associated with a higher risk of progression to hematological malignancies such as myelodysplastic syndromes or acute myeloid leukemia. Moreover, CH may participate to create a pro-inflammatory environment contributing to the pathogenesis of age-related diseases, such as cardiovascular diseases. This is likely to be driven by or translated in changes in bone marrow (BM) and/or peripheral blood (PB) soluble factors for which reference values still remain unclear, because BM cytokines levels have never been determined in strictly selected healthy people. Indeed, control BM samples classically used in studies are from subjects undergoing surgeries for non-hematologic causes, such as total hip replacement or cardiac surgery, patients suffering from immune thrombocytopenic purpura, brain death patients or allogeneic BM donors. In this study, the BM and PB plasma concentrations of 49 hematopoietic and inflammatory cytokines were measured in a representative panel of 94 healthy adult volunteers and the results were analyzed considering their age and presence of CH. METHOD Ninety-four healthy donors aged from 18.6 to 80.1 years old (yo), including 58 women were recruited for this study (HEALTHOX protocol, CPP Tours, AFSSAPS identifier ID-RCB: 2016-A00571-50 and ClinicalTrials.gov # NCT02789839). The presence or absence of CH (>1% of variant allele frequency) in this cohort is already known (Guermouche H, Ravalet N et al, Blood Adv 2020;4(15):3550-3557). BM samples were obtained through sternal aspiration using a classical procedure in France, and PB sampling was performed at the same time by venipuncture. Samples were collected on sodium heparin or EDTA, centrifuged twice (1200 g, 10 min, 20 C°), aliquoted and stored at -80°C. A 48-plex human cytokine panel assay was used to quantify 48 human cytokines in PB and BM plasmas [beta-NGF, CCL2, CCL3, CCL4, CCL5, CCL7, CCL11, CCL27, CLEC11A, CXCL1, CXCL8, CXCL9, CXCL10, CXCL12, FGF-2, G-CSF, GM-CSF, HGF, IFN-alpha-2, IFN-gamma, IL-1 alpha, IL-1 beta, IL-1ra, IL-2, IL-2-RA, IL-3, IL-4, IL-5, IL-6, IL-7, IL-9, IL-10, IL-12, IL-12B, IL-13, IL-15, IL-16, IL-17A, IL-18, KITLG, LIF, LT-alpha, M-CSF, MIF, PDGF subunit B, TNF, TNFSF10, VEGF-A]. MIF and FLT3L quantification were performed by ELISA. Regarding CH, the controls were subjects older than 50 yo without CH. Statistical analyses were performed with the R (3.6.3) and Rstudio version 1.2.5042 (www.rstudio.org) software. Comparisons were computed by Wilcoxon and Kruskal-Wallis tests. All pairwise multiple comparisons were performed using Dunn's-test for multiple comparisons of independent samples (PMCMR package). Correlations between cytokine levels in PB and BM were tested with Pearson and Spearman methods. Correlation matrices were plotted using the "corrplot" package. RESULTS CH was detected in 16 volunteers, mostly in individuals over 50 yo. BM and PB plasma samples were studied in 3 age-groups: 18-40, 40-60 and 60-80 yo. With aging, variations were observed for 18 BM cytokine levels, with 7 increasing (FLT3L, CXCL9, HGF, FGF-2, CCL27, IL-16, IL-18) and 8 decreasing (G-CSF, TNF, IL-2, IL-15, IL-17a, IL-4, LT-alpha, IL-1 alpha). In PB, 10 cytokines significantly increased with age (CXCL9, FLT3L, CCL27, CXCL10, HGF, CCL11, IL-16, IL-6, IL-1 beta, CCL2). CH was associated with significantly higher BM levels of MIF and IL-1 beta, lower BM levels of IL-9 and IL-5 and higher PB levels of IL-15, VEGF-A, IL-2, CXCL8, CXCL1 and G-CSF (Table). CONCLUSION In this study and for the first time, we concomitantly analyzed BM and PB concentrations of a panel of hematopoietic and inflammatory cytokines in a cohort of strictly selected healthy volunteers. In addition to the establishment of reference values, useful for various biological studies, and correlations between blood and BM levels, we identify variations in the BM of key cytokines according to age and CH. The differences in these cytokine concentrations, either as causes or as consequences, may shape both the BM microenvironment and hematopoietic processes, eventually leading to the beginning of age-related myeloid malignancies or inflammatory conditions. Figure 1 Figure 1. Disclosures Hirsch: Daiichi Sankyo Oncology: Consultancy; Novartis Pharma: Consultancy. Suner: Sanofi - Genzyme: Consultancy. Delhommeau: Celgene: Consultancy; BMS: Consultancy; Novartis: Consultancy.

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

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. Our results highlight increased ROS levels in BM nonlymphoid cells and especially in primitive CD34posCD38low progenitor cells. Moreover, we identified a specific antioxidant signature, dubbed “antioxidogram,” for the different MDS subgroups or secondary acute myeloblastic leukemia (sAML). Our results suggest that progression from MDS toward sAML could be characterized by 3 successive molecular steps: (1) overexpression of enzymes reducing proteic disulfide bonds (MDS with

The coexistence of dual hematological neoplasms is very rare. Sequential or synchronous neoplasms in hematology are an uncommon and complex clinical situation. The aim of the Hemo

Background: A current challenge in medical education is the steep exposure to the complexity and uncertainty of clinical practice in early clerkship. The gap between pre-clinical courses and the reality of clinical decision-making can be overwhelming for undergraduate students. The Learning-by-Concordance (LbC) approach aims to bridge this gap by embedding complexity and uncertainty by relying on real-life situations and exposure to expert reasoning processes to support learning. LbC provides three forms of support: 1) expert responses that students compare with their own, 2) expert explanations and 3) recognized scholars’ key-messages. Method: Three different LbC inspired learning tools were used by 900 undergraduate medical students in three courses: Concordance-of-Reasoning in a 1 st -year hematology course; Concordance-of-Perception in a 2nd-year pulmonary physio-pathology course, and; Concordance-of-Professional-Judgment with 3rd-year clerkship students. Thematic analysis was conducted on freely volunteered qualitative comments provided by 404 students. Results: Absence of a right answer was challenging for 1 st year concordance-of-reasoning group; the 2 nd year visual concordance group found radiology images initially difficult and unnerving and the 3 rd year concordance-of-judgment group recognized the importance of divergent expert opinion. Conclusions: Expert panel answers and explanations constitute an example of “cognitive apprenticeship” that could contribute to the development of appropriate professional reasoning processes.

7540 Background: Occupational pesticide exposure (OPE) is associated with the risk of developing lymphoid malignancies, but less information is available on large cohorts about the risk of occurrence of acute myeloid leukemia (AML). To answer this question, we performed a meta-analysis including relevant adult case-control studies which reported OPE. Methods: Following PRISMA and MOOSE guidelines, two investigators performed a systematic search in PubMed and Cochrane databases for case-control studies evaluating the association between OPE and AML between 1946 and August 28, 2018. In order to identify the maximum number of studies, keywords related to demographical, pesticides and chemicals data exposures were used. Studies reporting AML diagnosis based only on death certificates, controls from cancer databases and pediatric cases (

Abernethy malformation is a rare congenital anomaly of the portal vein where the portal blood bypasses the liver. We report the first case of a patient with Abernethy malformation and tetralogy of Fallot associated with nodular regenerative hyperplasia and focal nodular hyperplasia (FNH), which finally evolved to a giant hepatocellular-cholangiocarcinoma (HCC-CC) of the liver, successfully resected. (Hepatology 2016;64:1800-1802).

Introduction Moderate anemia affects a substantial fraction of the elderly population and blood smear analysis can help to guide towards a diagnosis of myelodysplastic syndrome (MDS). Nevertheless, in medical laboratories, review of blood smear is realized only if there is quantitative or qualitative flag on the complete blood count (CBC). Consequently, the suspicion of MDS could be delayed because of the absence of systematic blood smear triggering, this smear being crucial to induce the diagnosis process by cytological analysis of bone marrow aspiration. The DxH 800 Hematology Analyzer measures and calculates 126 cytological parameters based on photometry, impedance or light scatter. These parameters regroup 23 standard CBC parameters and 103 unexploited "research parameters". The goal of our study was to create an original mathematical model using "research parameters" to determine a Suspicion Score of MDS which triggers blood smear examination and consequently the process of identification of subclinical patients suffering from MDS. Methods This study compared the 126 parameters measured by the Beckman-Coulter DxH 800 Hematology Analyzer from peripheral blood samples of MDS patients and healthy volunteers. MDS cohort was composed of 101 patients of the university hospital of Tours (9 MDS-SLD, 28 MDS-MLD, 8 MDS-RS-SLD, 8 MDS-RS-MLD, 20 MDS-EB-1, 19 MDS-EB-2, 9 5q-). The cohort of healthy volunteers included 88 aged-matched subjects from HEALTHOX and PLASMYC protocols (ClinicalTrials.gov # NCT02789839 and # NCT02809222, respectively). The "research parameters" contained Research Use Only (RUO) parameters and Cell Population Data (CPD). CPD were composed of 98 parameters measured by Volume Conductivity Scatter (VCS) module. The parameters derived from reticulocytes, which require a specific prescription, were excluded. Statistical analyses were performed using Rstudio version 1.0.153. The normal distribution of values was studied by Shapiro-Wilk tests (p-value0.05). Means comparisons were performed by Wilcoxon and Student tests. Principal component analysis (PCA) was performed using FactoMineR. The logarithmic logistic regression was done thanks to the glm() function of the stats package. The general linear model was obtained by using logistic regression with weighted parameters and was validated by split-sample strategy (10,000 repeats). Samples were divided into two groups ("learning" and "test" groups) randomly mixing MDS patients and healthy volunteers. The "learning" group (n=130) allowed to build the model and the "test" group (n=59) was used to validate it. Results After mono-parametric and multi-parametric comparisons, 10 parameters were selected to establish the model of interest according to the best contributions at the first axe of PCA, the best correlations at two first axes of PCA and the most significant p-values (parameters described in the Table: MN.LALS.NNRBC, MN.LMALS.NNRBC, MN.UMALS.NNRBC, SD.MALS.NE, SD.UMALS.NE, SD.V.NE, MN.MALS.NE, SD.AL2.NE, SD.AL2.MO, SD.V.MO ). In order to determine the Suspicion Score of MDS (SS-MDS), the 10 selected parameters were weighted during split sampling strategy by logistic regression. After repeat of 10,000 split-samples, the SS-MDS determined using weighted parameters was validated with average efficiency of 92.3%. For each parameter, the median of weighting coefficients was used in the mathematical model: "SS-MDS = ΣCi.Pi + intercept" with "Ci: weighting coefficient of parameter i" and "Pi: parameter i value". On the whole cohort, SS-MDS induced "MDS" flag for 11 MDS patients (red points in the Figures) for which conventional CBC algorithms failed to generate flag spreading peripheral blood smear. By fixing the threshold at -1.5, the sensitivity and specificity of SS-MDS were 100% and 92%, respectively. Moreover, the positive and negative predictive values were 93.5% and 100%, respectively. Conclusions The incidence of MDS increases with aging and the early diagnosis enables optimal care of these diseases. The Beckman-Coulter DxH 800 HematologyAnalyzer is widely used over the world. We propose in this study the clinical use of 10 unexploited "research parameters" to early detect subclinical MDS by selective triggering of blood smear examination. A prospective/multicentric study will allow the optimization of SS-MDS. Figure. Figure. Disclosures No relevant conflicts of interest to declare.

Professionalism development entails learning to make judgments in ambiguous situations. A Concordance of Judgment Learning Tool (CJLT), comprised of 20 vignettes involving professionalism issues, was developed. Students obtained a measure of how concordant their judgments were with a panel of experts and learned from given explanations.Twenty clinical vignettes implying professionalism issues were written including, for each, four possible courses of action. Expert panel, nominated by all clerkship students, was made up of attending physicians that best represented professionalism role models. Experts completed CJLT and gave explanations for their answers. All clerks were invited to answer each vignette, and then received automated expert feedback including explanations.Seventy-nine students sat for the activity. The optimized test included 20 cases and 54 questions (Cronbach's alpha coefficient of 0.64). Student - expert concordance scores ranged from 54 to 77 with a mean at 64.6 (standard deviation 5.1). Satisfaction survey results indicated high satisfaction and relevance of tool despite some pitfalls. Post-test focus group data revealed relevant experiential learning on professionalism issues.Students' scores and perceptions suggest pedagogic relevance of the CJLT in fostering professionalism development in clerkship. CJLT is user-friendly and shows promise as a situation experiential learning activity.

of 50 physicians, postgraduate specialists, senior nurses, medical and nursing students and patients. Participants were asked to narrate critical incidents related to deficiencies in communication skills in physicians in which they had been involved or which they had witnessed first-hand. Eighty-one critical incident narrations were recorded and transcribed. They were analysed and grouped according to themes, categories and sub-categories. Communication skills deficiencies were identified from the themes, categories and sub-categories. In-depth analysis of communication gaps, cultural or contextual influences and their medical consequences were identified. One critical incident referred to the failure of a physician to identify the locus of decision making. An individual in need of surgery for a hernia was also at risk for cardiac complications during surgery. The patient felt that his family needed to make the decision, whereas the physician demanded that he make the decision. Another example referred to the fact that ward rounds are usually conducted in English, a language most patients do not understand. One day during discussions at the bedside, the word ‘surgery’ was mentioned causing much unnecessary anxiety and alarm in an elderly female patient. These are two of the incidents narrated which illustrate poor communication with medical consequences. What lessons were learned? Four categories of communication deficiency were developed from the narrated incidents: (i) content omission (8 sub-categories); (ii) inappropriate responses (6 sub-categories); (iii) inappropriate setting (4 sub-categories), and (iv) non-verbal communication issues (6 subcategories). These categories and sub-categories formed an interrelated framework for the content and learning activities of a new communication skills course for Sri Lankan doctors. Critical incident analysis themes provided the content necessary to design a culturally and contextually relevant solution to a significant problem in physician communication in Sri Lanka. The 81 authentic scenarios will also be useful in the teaching process during this course.