bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thromboelastographic Follow-Up Of Prophylactic Thrombocyte Transfusion
Authors: Sahin Deniz Goren , Akay Olga M. , Karagulle Mustafa , Gunduz Eren , Gulbas Zafer 
Published: October 2019

Introduction
Prophylactic thrombocyte transfusion is being used to reduce increased bleeding risk after chemotherapy treatment for leukemia or malignancy. This transfusion is frequently applied when thrombocyte count is below <10.000/uL or between 10.000 and 20.000/uL. However, it was shown that thrombocyte count alone is not enough for determining bleeding risk. Moreover, given the fact that thrombocyte transfusions have inherent risks and economic burden, new laboratory approaches such as thromboelastography can be considered to determine bleeding risk in these patients. Thromboelastography is a new alternative method to conventional coagulation tests, which gives information about hemostatic system by evaluating clot’s visco-elastic and mechanical features. The aim of our study to establish a transfusion algorithm by thromboelastographic follow-up of prophylactic thrombocyte transfusion.

Methods
Eighty patients who have been diagnosed as acute leukemia were randomized into 4 groups. Six units random thrombocyte was given to the first group, three units random thrombocyte was given to the second group, one unit apheresis was given to the third group, and ½ unit apheresis was given to the fourth group. Before and 15 minutes after transfusion, peripheral blood was taken and CBC and rotation thromboelastograpy (ROTEM) was performed by standard device (Pentapharm GmbH, Munich, Germany). Clotting time (CT), clot formation time (CFT), and maximum clot firmness (MCF) were evaluated by 2 methods, in-TEM and ex-TEM. Patients were followed up during study by using clinical bleeding signs based on WHO bleeding grade. Patients who used medications that can affect thrombocyte functions within the last 14 days and patients who have systemic disorders (renal, hepatic, endocrinological) or hemostatic disorders were not included in this study. Variance analysis was used in order to find out statistical differences. P<0.05 was considered statistically significant.

Results
When platelet counts and ROTEM results were analyzed for each parameter before platelet transfusion, there were no statistically significant differences among groups. We analyzed the differences of platelet counts and thromboelastographic parameters before and after prophylactic platelet transfusion and we didn’t see any statistically significant differences between groups. Clinical bleeding signs were not correlated with platelet count in any groups.

Conclusion
Six units random, three units random, complete apheresis or half apheresis prophylactic platelet transfusion does not cause any significant changes in platelet count, ROTEM parameters and clinical bleeding signs. Therefore, low dose platelet transfusion can be considered because of its lower economic burden. Moreover, further studies are needed to evaluate the potential of ROTEM as an independent factor for transfusion indication.

Disclosures:
No relevant conflicts of interest to declare.
Targeted correction Of RUNX1 Mutation In The FPD Patient-Specific Induced Pluripotent Stem Cells Restores Megakaryocytic Differentiation
Authors: Kwon Erika Mijin , Connelly Jon P , Gao Yongxing , Horwitz Marshall , Cheng Linzhao , Liu Pu Paul 
Published: October 2019

Abstract
Familial platelet disorder with propensity to acute myeloid leukemia (FPD/AML) is a rare autosomal dominant disease caused by RUNX1 mutations. RUNX1 encodes a transcription factor, which is frequently mutated in leukemias. It is also essential in early hematopoiesis and megakaryocytic differentiation. FPD patients have a mild to moderate bleeding disorder, thrombocytopenia, and over 35% of patients will develop AML during their lifetime. Currently there are no suitable animal models for the disease, making it necessary to develop alternative approaches for research studies.
To develop an in vitro model of FPD, we established induced pluripotent stem cell (iPSC) lines using episomal, non-integrating vectors from skin fibroblasts from a family of FPD patients harboring a nonsense mutation in the C-terminal region of the RUNX1 (Y260X). The derived iPSC lines showed typical characteristics of pluripotency such as teratoma formation and expressions of pluripotency markers (Oct4, Sox2, Nanog, and Tra-1-81). In order to correct the mutation in the patient-specific iPSCs by homologous recombination, we designed a pair of RUNX1 zinc finger nucleases (ZFNs) and a targeting vector. We then performed ZFN-mediated gene targeting in one of the FPD iPSC lines and confirmed correction of the mutant RUNX1 allele in at least two iPSC clones by Southern, FISH and sequence analyses. RUNX1 mRNA expression analysis of the FPD iPSC line and the corrected iPSC lines showed expression of only wildtype RUNX1 transcripts in the corrected iPSC lines, but not in the uncorrected lines. Furthermore, we directed hematopoietic differentiation of the FPD iPSCs and the corrected iPSC lines using the spin embryoid body formation method. We found defects in hematopoietic differentiation of FPD iPSCs, particularly towards megakaryopoiesis. Importantly, ZFN-mediated mutation correction rescued the hematopoietic differentiation defects with almost double the number of CD41a+/CD42a+ megakaryocytes produced from the corrected iPSCs.
Our results collectively demonstrate successful in vitro modeling of FPD using iPSC lines with an innovative approach to correct the RUNX1 mutation by gene targeting. Mutation correction rescues the hematopoietic defects, indicating that hematopoietic stem cell transplantation using patient-specific iPSC lines has great potential to treat the FPD patients in the future.

Disclosures:
Horwitz: United States Government: Consultancy, United States ex rel. Horwitz v. Amgen Inc., Civil Action No. C07-0248 (W.D. Wash.) Other.
Expanding The TLX1-Regulome In T Cell Acute Lymphoblastic Leukemia Towards Long Non-Coding RNAs
Authors: Durinck Kaat , Van der Meulen Joni , Ongenaert Maté , Volders Pieter-Jan , Wallaert Annelynn , Van Roy Nadine , Benoit Yves , Poppe Bruce , Mestdagh Pieter , Vandesompele Jo , Rondou Pieter , Soulier Jean , Van Vlierberghe Pieter , Speleman Frank 
Published: October 2019

Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer that results from the malignant transformation of T-cell precursors and affects children, adolescents and adults. In T-ALL, genetic lesions in several possible oncogenes and tumor suppressors have been shown to cooperatively contribute to leukemogenesis. The TLX1 (T-cell leukemia homeobox protein-1, HOX11) oncoprotein is aberrantly expressed in in 5-10% of pediatric patients and 30% of adult T-ALL patients due to chromosomal translocations. Although many downstream protein coding targets genes of TLX1 have been identified, the non-coding network downstream of TLX1 remains elusive. In this study we expand the TLX1 regulome towards long non-coding RNAs (lncRNAs). Hereto we measured the transcriptional response of all protein coding genes and 12,000 lncRNAs following TLX1 knock down in the ALL-SIL cell line using a custom designed mRNA/lncRNA expression platform (Agilent). In addition, similar mRNA-lncRNA expression profiles of 64 primary T-ALL patient samples were generated which included five TLX1+ cases. To establish the direct transcriptional TLX1 targets, we generated TLX1 ChIP-sequencing data from ALL-SIL leukemic cells. We confirm direct regulation of previously established protein coding gene targets and de novo TLX1 motif discovery also identified RUNX1 as an important mediator of the global TLX1 transcriptional network (Della Gatta et al., Nature Medicine, 2012). Complementary to these data, our analysis for the first time establishes the TLX1 driven lncRNAome in thymocyte derived leukemic cells. Remarkably, the majority of TLX1 controlled lncRNAs were upregulated suggesting that they may be implicated in the TLX1 driven repression of protein coding gene expression. Finally, pairwise mRNA-lncRNA correlation analysis allowed functional annotation of TLX1 targeted lncRNAs. In conclusion, we present the first landscaping of the genome-wide binding pattern of TLX1 and provide evidence for a previously unestablished role of lncRNAs in the TLX1 regulatory network.

Disclosures:
No relevant conflicts of interest to declare.
Voriconazole Exposure and The Risk Of Cutaneous Squamous Cell Carcinoma In Allogeneic Hematopoietic Stem Cell Transplant Patients
Authors: Hashmi Shahrukh K , Wojenski Daniel , Bartoo Gabriel , Merten Julianna A. , Dierkhising Ross , Elazhary Rokea , Wilson John W , Wolf Robert , Patnaik Mrinal M. , Hogan William , Litzow Mark R. 
Published: October 2019

Abstract

Background
Voriconazole is a common antifungal medication used in allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients. In solid organ transplantation, multiple studies have associated the use of voriconazole with the development of squamous cell carcinoma (SCC) post-transplant, but its association with SCC in allo-HSCT patients is unknown. We sought to determine this association.

Methods
After IRB approval, Mayo Clinic’s transplant database (2007-2012) was accessed and electronic charts of allo-HSCT patients were retrospectively reviewed. Voriconazole exposure was defined as exposure to voriconazole at any time during treatment of primary disease, prior to or following HSCT. Cumulative voriconazole exposure was defined as total days of voriconazole use following HSCT; days were not required to be consecutive. Two time-dependent voriconazole exposure variables were defined: (1) history of voriconazole exposure (yes/no) over time, and (2) cumulative days on voriconazole over time.

Results
404 patients underwent allo-HSCT during this timeframe, and 381 patients (table 1) were included in the final analysis. 23 patients were excluded (8 patients received multiple transplants, 9 patients were treated under pediatric protocols, 6 patients lacked research consent). 312/381 received voriconazole; other antifungal therapy included fluconazole (n=40), posaconazole (n=23), anidulafungin (n=1), and caspofungin (n=5). Median duration of cumulative days of voriconazole was 214 (range 2 -1553). SCC developed in 26/312 exposed to voriconazole and in 1/69 who received alternative antifungals. Cumulative incidence of SCC at 1 year was 3%, 2 years was 8%, 3 years was 13%, 4 years was 14%, and at 5 years was 19% (figure 1). Cumulative days of voriconazole use was found to be a risk factor for the development of SCC, and this relationship persisted in a multivariate model using previously identified risk factors (gender, age at transplant, TBI conditioning regimen, skin cancer pre-HSCT, chronic GVHD) as covariates (HR 1.859 for each 180 days of use, p<0.001). History of prior voriconazole exposure was not associated with an increased risk of SCC after covariate adjustment (HR 2.436, p=0.2369).

Conclusion
This is the first study to establish cumulative days of voriconazole use as a risk factor for SCC development following allo-HSCT, and may help guide appropriate antifungal prophylaxis in this patient population which is already at an increased risk of developing skin cancers.

Disclosures:
No relevant conflicts of interest to declare.
Epo Dependent Signaling In Macrophages Regulates Stress Erythropoiesis
Authors: Paulson Robert F. , Xiang Jie , Hariharan Sneha 
Published: October 2019

Abstract
Steady State erythropoiesis occurs in the bone marrow and is primarily homeostatic. In response to anemic stress the need for new erythrocytes quickly outpaces the erythropoietic capacity of steady state erythropoiesis. At these times, stress erythropoiesis predominates. Stress erythropoiesis is best understood in mice where this process is primarily extra-medullary occurring in the adult spleen and liver and in the fetal liver during development. Stress erythropoiesis utilizes progenitors and signals that are distinct from steady state erythropoiesis. Using a variety of experimental systems, we have developed a model for stress erythropoiesis during the recovery from anemic stress. This recovery can be divided into three stages. Amplification of progenitors that exhibit stem cell properties, the induction of a signal that promotes the switch from amplifying stress progenitors to differentiating stress progenitors and the final stage where stress progenitors rapidly differentiate into new erythrocytes. We have identified specific stress progenitor populations at each stage on this process as well as the signals that regulate the amplification, the switch to differentiation and differentiation of stress erythroid progenitors. Here we show that macrophage dependent signals play key roles at each stage of stress erythropoiesis. The transition from amplifying stress erythroid progenitors to differentiating stress erythroid progenitors is mediated by Epo dependent signaling in macrophages which changes the signals made by the macrophage microenvironment from those that promote amplification (Wnt family factors) to those that promote differentiation (PGE2). This paradigm is true for murine and human stress erythroid progenitors. This analysis reveals a dynamic interplay between progenitor cells, the macrophage microenvironment and hypoxic tissues in vivo during the recovery from anemic stress.

Disclosures:
No relevant conflicts of interest to declare.
A Novel Path for ATRA Differentiation Therapy in Acute Myeloid Leukemia with Isocitrate Dehydrogenase Mutations
Authors: Sarry Jean-Emmanuel , Boutzen Helena , Récher Christian 
Published: October 2019

Abstract
Acute myeloid leukemia (AML) is characterized by accumulation of malignant blasts with impaired differentiation programs due to recurrent mutations, among which IDH mutations occur in 15% of AML patients. These mutations lead to a block in erythroid commitment while they may also bias hematopoietic differentiation to myeloid lineage. Interestingly, Lyn tyrosine kinase is required for erythroid differentiation and we have observed a reduction of Lyn expression in the presence of IDH1-R132H mutation. It is also a negative regulator of ATRA-induced granulocytic differentiation. Accordingly, we hypothesized that IDH mutations may sensitize AML cells to ATRA-induced differentiation.
Here, we report that clinically achievable doses of ATRA are sufficient to trigger differentiation specifically on AML cell lines, primary patient samples and xenograft mice models carrying IDH1 mutation as observed by an increase in CD11b expression, granulocytic enzyme activity and morphologic changes in May-Grunwald-Giemsa staining. We also showed that ATRA-induced terminal granulocytic differentiation increases apoptosis while decreases proliferation and colony formation specifically in IDH1 mutant cells. Moreover, inhibition of IDH1-R132H activity reduced ATRA-sensitivity while increasing expression of IDH mutation correlated with highest ATRA sensitivity. Furthermore, treatment with a cell-permeable form of the oncometabolite specifically produced by the mutant (eg. 2-HydroxyGlutarate) sensitized AML cells to ATRA-induced differentiation. Finally, because ATRA-induced differentiation triggers a transient increase of Lyn activation, its association with Lyn inhibitors synergistically increased ATRA-induced differentiation of IDH mutant blasts.
In summary, our results showed that IDH mutations by producing 2-HG sensitized leukemic blasts to ATRA and that this synergizes with Lyn inhibition. Since 2HG concentration reaches millimolar in AML patient serum and is 100-fold higher in IDH mutated patients than in non-mutated ones, we would predict a strong efficacy and specificity of ATRA. Furthermore, as IDH mutations are systematically conserved at relapse, this therapeutic strategy might be promising to achieve a long-term remission specifically for this AML patient subgroup.

Disclosures
No relevant conflicts of interest to declare.
Interacting populations affecting proliferation of leukemic cells in culture
Authors: Aye MT , Till JE , McCulloch EA 
Published: October 2019

Abstract
Peripheral blood cells from three patients with acute leukemic have been studied using a suspension culture method previously described.1 Cytogenetic studies in two of the patients permitted the identification of the proliferating cells in the cultures as being derived from a leukemic population. Cell separation studies using velocity sedimentation supported the concept that growth of the leukemic cells in culture is dependent on an interaction between two populations of leukemic cells.
Sex hormones and the regulation of erythroid spleen colonies development of fetal liver origin
Authors: Bleiberg I , Perah G 
Published: October 2019

Abstract
The development of erythroid colonies of fetal liver hemopoietic cell origin in adult irradiated polycythemic mice was studied. It was found that orchidectomy sharply reduced the number of erythroid colonies developed in the spleen of these polycythemic male recipients. Estrogen injection to the orchidectomized polycythemic recipient did not further decrease the number of erythroid colonies developed. It is concluded that the development of erythroid colonies of fetal liver origin in polycythemic male recipients is maintained mainly by testicular testosterone. The complete suppression of these colonies in female recipients does not seem to be a result of inhibition by estrogen.
Tolerance to the granulocyte-releasing and colony-stimulating factor elevating effects of endotoxin
Authors: Quesenberry P , Halperin J , Ryan M , Stohlman F Jr 
Published: October 2019

Abstract
Injection of Salmonella typhosa endotoxin into either CF1 or C57bl/6J mice leads to prompt increases in serum colony-stimulating factor (CSF). Repeated injections of endotoxin result in a dose-related hyporesponsiveness or tolerance to this effect. Tolerance is seen after either intravenous (i.v.) or intraperitoneal (i.p.) routes of administration or challenge and occurs after one to two preinjections. Cross-tolerance to heterologous endotoxin (Escherichia coli) was also shown. This cross-tolerance is complete immediately after cessation of preinjections, but partial at later time intervals. Levels of a serum inhibitor of colony growth were decreased in tolerant mice, although this decrease is not statistically significant. Tolerant mice injected with endotoxin release granulocytes from the bone marrow normally, in spite of the absence of a CSF response. This suggests that neutrophil releasing activity (NRA) and CSF are separate entities. A marked marrow granulocytic hyperplasia develops after 7 or 20 days of endotoxin injections, despite the tolerance to the CDF-elevating effect of endotoxin. This granulocytic hyperplasia could still be mediated by serum CSF increases. A negative medullary feed-back secondary to the repetitive release of marrow granulocytes, however, is an equally plausible mechanism for the stimulation of granulocyte production. It is also possible that the decrease in serum inhibitors played a role in the sustained increase in granulopoiesis seen here.
A measurement technique for cell adhesiveness
Authors: Young IT , Sher SE 
Published: October 2019

Abstract
Determination of the percentage of cells in clumps on a stained smear of human peripheral blood porvided a useful, accurate technique for measuring cell adhesiveness. Smears of human peripheral blood drawn with EDTA were prepared on a blood slide centrifuge, stained, and examined under a light microscope. Statistical analysis showed that the method resulted in a Poisson distribution of particles on the slide, where a particle was considered to be a simple cell, or two or more cells which appeared to be touching, Analysis of the distributions of erythrocytes and leukocytes showed that clumps were formed before the cells were deposited on the slide. When adhesiveness of erythrocytes or leukocytes was increased by incubation with antiserum to the corresponding cell type, the percentage of that cell type in clumps increased proportionately, Preliminary results using the method showed that normal human donors had similar to 1% of their erythrocytes and 1- 5% of their leukocytes in clumps. In chronic myelocytic leukemia, as many as 60% of the leukocytes were in clumps.
Total folate binding capacity of normal human plasma, and variations in uremia, cirrhosis, and pregnancy
Authors: Colman N , Herbert V 
Published: October 2019

Abstract
The current study presents evidence that all human serum contains a class of high-affinity folate binders (KA=2.8 X10(10 liters/mole), which migrate as a single peak on gel filtration. Failure of previous studies to detect this characteristic in all but a minority of subjects is attributable to its variable, often total, saturation. Direct measurement of the total folate binding capacity (TFBC) has been made possible by dissociation of endogenous folate-binder complexes at acid pH, removal of free folate by coated charcoal, and radiofolate tagging. This procedure does not appear to significantly denature the binders, which release and rebind similar quantities of 3H-PGA. In 20 normal subjects, TFBC ranged from 100 to 325 pg/ml (mean+/-SE = 174+/-16), and was always at least 33% saturated. In three clinical conditions, all associated with elevated unsaturated folate binding capacity, three different patterns emerged when TFBC was also measured. Uremic subjects had significantly elevated mean TFBC with normal saturation. In cirrhotic subjects, mean TFBC approximated normal, but saturation was significantly decreased. In pregnancy, two groups were seen: one with increased TFBC and the other with a normal TFBC, some of whom had decreased saturation. Lactobacillus casei serum folate level was about 30 times greater than the TFBC; there was no correlation between the two measurements.
Cytogenetic evidence for recurrence of acute myelogenous leukemia after allogeneic bone marrow transplantation in donor hematopoietic cells
Authors: Elfenbein GJ , Brogaonkar DS , Bias WB , Burns WH , Saral R , Sensenbrenner LL , Tutschka PJ , Zaczek BS , Zander AR , Epstein RB , Rowley JD , Santos GW 
Published: October 2019

Abstract
A 22-yr-old man with acute myelocytic leukemia received a bone marrow transplant from a genotypically HLA-identical female sibling after cyclophosphamide preparation. He remained in complete remission for 18 mo, when he developed a chloroma in the perineum. The chloroma was treated with local radiotherapy. The chloroma recurred 8 mo later and was treated with radiotherapy followed by combination chemotherapy. At 34 mo after transplant, marrow relapse and chloroma were documented. The first chloroma contained host cells by fluorescent Y-chromatin body analyses of interphase nuclei. All metaphase cells and karyotypes from peripheral blood and marrow samples showed no evidence of host cells from 3 wk after transplant through the time of marrow relapse. Data from autosomal and sex chromosome studies indicate that the marrow relapse occurred in cells of donor origin. A new consistent chromosome abnormality [45, X, -X, t(8;21) (q22; q22)] was observed in a majority of donor cells. The patient received a second bone marrow transplant from the same donor after preparation with busulfan and cyclophosphamide and attained a complete remission with full hematologic engraftment.