bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frequent Epigenetic Inactivation of MSX2 In Acute Myeloid Leukemia
Authors: Zhao Chen , Han Xin , Zhang Yu H. , Huang Xiaoyan , Dai Aili , Lu Gary , Yin C. Cameron , Chen Ling , You M. James 
Published: October 2019

Abstract
Abstract 4645
DNA hypermethylation has been implicated in the tumorigenesis and prognosis in acute myeloid leukemia (AML). To identify and validate relevant methylated genes in AML, we have compared expression levels and methylation status of 26 candidate genes. One of the interesting candidates identified in our study is MSX2. MSX2 is a member of muscle segment homeobox gene family. MSX2 plays a role in promoting cell growth under certain conditions and may be an important target for RAS signaling pathways. However, the mechanism of transcriptional regulation and functional role of MSX2 in hematological malignancies, especially AML, are poorly understood. In our study, we determined the methylation status, and analyzed the expression levels of MSX2 in AML cell lines and primary AML cells using RT-PCR and/or Taqman real-time PCR. MSX2 mRNA expression was robust in the normal granulocytes and blasts of human bone-marrow, but was either absent or significantly diminished in 6 of 9 (66.7%) AML cell lines. The expression levels of MSX2 in those 6 AML cell lines were restored after treatment of 5-aza 2′-deoxycytidine. In addition, COBRA (Combined Bisulfite Restriction) analysis demonstrated hypermethylation of MSX2 in those AML cell lines (6 of 9, 66.7%), and partial methylation in 3 of 9 AML cell lines. The methylation status was inversely correlated with the mRNA expression levels of MSX2 in those cell lines. Furthermore, the expression levels and methylation status of MSX2 in human primary AML cells were evaluated. COBRA analysis demonstrated frequent hypermethylation of MSX2 in primary AML patient samples (19 of 32, 59.3%). Importantly, the mRNA expression levels of MSX2 as shown by Taqman real-time PCR in those 19 primary AML patient samples were inversely correlated with the methylation status of MSX2. These findings confirmed the role of frequent DNA hypermethylation in silencing MSX2 in AML. We are in the process of determining the functional role of MSX2 in the pathogenesis of AML. In addition, diagnostic and prognostic values of MSX2 in AML are being pursued.

Disclosures:
No relevant conflicts of interest to declare.
Dysregulation of miRNAs In AL Amyloidosis
Authors: Weng Liangping , Spencer Brain , Hoo Pam Soo , Connors Lawreen , O'Hara Carl , Seldin David C 
Published: October 2019

Abstract
Abstract 4648
Bone marrow plasma cells (BMPC) were purified from aspirates obtained from patients with AL amyloidosis using anti-CD138 immunomagnetic beads, and from controls. Expression levels of micro RNAs (miRNAs) were compared by microarray. The levels of ten miRNAs were found to be increased more than 1.5-fold in BMPC of AL amyloidosis patients. These results were confirmed using stem-loop RT-qPCR for miR-148a, miR-26a, and miR-16, the most highly upregulated miRNAs in the AL samples. miR-16, a micro RNA linked to other hematopoietic diseases, was significantly increased in the AL group at baseline and also in treated patients with persistent monoclonal plasma cells in the bone marrow, but not in patients who achieved a hematologic remission after therapy and normal polyclonal BMPCs. miR-16 can be derived from the miR-16-1/mirR-15a cluster on chromosome 13 or the miR-16-2/miR-15b cluster on chromosome 3. The expression of miR-15b was much higher than miR15a in AL and control BMPC samples; this suggests that miR-16 in plasma cells is mostly derived from chromosome 3. The anti-apoptosis gene BCL-2, a putative target mRNA that can be down-regulated by miR-16, was present in the BMPCs from the AL group despite the elevated levels of miR-16. Our data suggest that miRNAs are dysregulated in clonal plasma cells from AL amyloidosis patients and that abnormal levels of miRNAs may be potential biomarkers for disease.

Disclosures:
No relevant conflicts of interest to declare.
Acquired Von Willebrand Syndrome In Mitral Valve Leak
Authors: Pérez-Rodríguez Almudena , de Faria Maria Joana Costa Pinto Prego , Fraga Esther Lourés , Rodríguez-Trillo Angela , Cuenca José Joaquín , Batlle Javier , Fernanda López-Fernández Maria 
Published: October 2019

Abstract
Abstract 4657

Background
Several studies have shown that between 15% to 25% of patients with severe aortic stenosis present bleeding episodes that may be attributed to an acquired von Willebrand syndrome (AVWS). Until now, to our knowledge, no association of AVWS with mitral valve disfunction has been reported.

Design and Methods
Four patients with mitral valve leak presented acquired abnormalities of von Willebrand factor (VWF) and a bleeding history. Two of them presented severe bleedings requiring blood transfusions. All of them were within an adequate range of oral anticoagulation.

Results
Prior to surgery, these patients presented an APTT prolonged and in two of them the closure time determined by the platelet function analyzer (PFA-100®) (with COL/ADP and COL/Epi) was prolonged also. Factor VIII procoagulant activity (FVIII:C), VWF antigen (VWF:Ag), VWF ristocetin cofactor activity (VWF:RCo) and VWF collagen binding (VWF:CB) were considerably elevated and the VWF multimers in plasma, showed a lower relative proportion of the high molecular weight VWF multimers (HMWM), to some extent similar to type 2A congenital von Willebrand disease (VWD). In two of them, the VWF:RCo/VWF:Ag or VWF: CB/VWF:Ag ratios were less than normal range (>0.7) while in the other two were normal. After surgery, FVIII:C, and VWF properties were extremely increased and the ratios VWF:RCo/VWF:Ag and VWF: CB/VWF:Ag > 0.7. After surgery, FVIII:C, VWF:Ag, VWF:RCo and VWF:CB increased considerably. The ratios were > 0.7. The PFA-100® (COL/ADP and COL/Epi) was corrected in the two patients who had it prolonged. The multimeric VWF profile were also corrected in all of them.

Conclusions
The present study describes acquired VWF qualitative alterations for the first time in mitral valve leak. When such alterations are important they may be associated or to contribute to a bleeding diathesis. This problem was reported previously in aortic valve stenosis in relationship with a suspected very high shear stress. This situation may be not usually present in mitral valve stenosis, but it seems that it must occur in the presence of mitral valve leak. Consequently, the AVWS should be taken into account in patients with mitral valve leak that present a bleeding diathesis, not explained by an excess of oral anticoagulation.

ACKNOWLEDGEMENTS
This work was supported by the Fondo de Investigación Sanitaria, F.I.S. Carlos III, Ministerio de Sanidad, Spain (FIS PI# 07/0229), and Consellería de Innovación e Industria, Xunta de Galicia (INCITE08ENA916109ES).

Disclosures:
No relevant conflicts of interest to declare.
Biochemical Characterization of a Recombinant FIX Drug Candidate for Treatment of Hemophilia B
Authors: Turecek Peter , Vejda Susanne , Varadi Katalin , Rottensteiner Hanspeter , Boehm Ernst , Reiter Manfred , Kaliwoda Martin , Mundt Wolfgang , Ehrlich Hartmut J. , Scheiflinger Friedrich 
Published: October 2019

Abstract
Abstract 4658
Human coagulation factor IX (FIX) is a vitamin-K-dependent coagulation factor whose absence or dysfunction causes hemophilia B. Treatment of hemophilia B is based on replacement therapy using highly purified FIX concentrates.
Baxter has developed a recombinant factor IX for treating hemophilia B patients that is produced in a CHO cell-line using a serum and protein-free fermentation technology. The purification process avoids the use of immune-affinity chromatography and includes two viral reduction steps. The final drug product is formulated in the absence of proteins of animal or human origin. Baxter's recombinant FIX resembles commercially available rFIX in most characteristics with the exception of a significantly lower FIXa content, which might improve standardization compared to commercial rFIX products.
Preclinical and clinical lots of rFIX were characterized with respect to their hemostatic potency, efficiency of activation by FXIa and FVIIa in the presence of tissue factor, and capacity to bind to phospholipid vesicles. Three lots of commercial rFIX with different potencies and one lot of a plasma-derived FIX product were included in the study. Similarity could be shown between the preclinical and clinical lots of rFIX in all these assays. Furthermore, the functional and biochemical characterization of Baxter's recombinant FIX showed that it resembles the recombinant comparator product. The phase I clinical trial which has been initiated will now have to show whether Baxter's rFIX can become an alternative drug candidate product for treating patients suffering from hemophilia B.

Disclosures:
Turecek: Baxter Innovations GmbH: Employment. Vejda:Baxter Innovations GmbH: Employment. Varadi:Baxter Innovations GmbH: Employment. Rottensteiner:Baxter Innovations GmbH: Employment. Boehm:Baxter Innovations GmbH: Employment. Reiter:Baxter Innovations GmbH: Employment. Kaliwoda:Baxter Innovations GmbH: Employment. Mundt:Baxter Innovations GmbH: Employment. Ehrlich:Baxter Innovations GmbH: Employment. Scheiflinger:Baxter Innovations GmbH: Employment.
The Frequency and Clinical Significance of Thrombocytopenia Complicating Critical Illness: A Systematic Review
Authors: Hui Philip LY , Cook Deborah J , Lim Wendy , Fraser Graeme , Arnold Donald M. 
Published: October 2019

Abstract
Abstract 4664

Background:
The epidemiology of thrombocytopenia in critically ill patients has not been well characterized. The objective of this study was to systematically review the prevalence, incidence, risk factors for, and consequences of thrombocytopenia among critically ill patients.

Methods:
We searched MEDLINE, EMBASE, the Cochrane Registry for controlled trials (until May 2010), and the Online Computer Library as well as bibliographies of relevant studies to identify investigations designed to examine the frequency, risk factors and/or outcomes associated with thrombocytopenia among patients admitted to the intensive care unit (ICU). We selected studies, abstracted data and assessed methodological quality in duplicate, independently. Heterogeneity of design and analysis precluded statistical pooling of results.

Results:
We identified 23 studies (12 prospective) enrolling 6,568 patients from medical, surgical, mixed, cardiac or trauma ICUs. Prevalent thrombocytopenia (on ICU admission) occurred in 8.3 – 67.6% of patients; incident thrombocytopenia (developing during the course of the ICU stay) occurred in 13.0 – 44.1% patients. High illness severity, organ dysfunction, sepsis and renal failure were common risk factors. Only 1 study using multivariate analysis examined whether thrombocytopenia was associated with major bleeding but found no association. Six out of 8 studies using multivariate analysis found that thrombocytopenia increased the risk of death.

Conclusion:
The frequency of thrombocytopenia during critical illness varies widely based on case mix and definition. Thrombocytopenia appears to increase the risk of death after adjustment for confounding factors. The association between thrombocytopenia and bleeding in the ICU has not been adequately examined. Although thrombocytopenia was associated with poor outcomes in most studies, randomized trials of platelet transfusions or other interventions aimed at increasing the platelet count are needed to determine whether improvement of thrombocytopenia can modify these risks.

Disclosures:
No relevant conflicts of interest to declare.
Reticulated Platelets Quantification In An Automatic CBC Counter and Its Role In Thrombocytopenia Etiology Assessment
Authors: Simoes Ana Teresa , Barreira Rogério , Oliveira Ana Cristina , Pinheiro Ana Cristina , Ferreira Patrícia , Duarte Marta , Salvado Ramón , Ribeiro Maria Leticia , Santos Susana Almeida 
Published: October 2019

Abstract
Abstract 4672

INTRODUCTION:
Reticulated platelets (rP) are young platelets, recently released from the bone marrow, and contain more cytoplasmic RNA elements than mature platelets. Considerable amount of evidence suggests that rP analysis may be useful in the investigation of platelet disorders. Automatic quantification methods have been developed; however, the methodology has not yet been standardized and validated in clinical practice.

STUDY PURPOSE
To analyze the rP percentage (rP%) in 168 samples, using software version v3 in Cell Dyn® Sapphire, in correlation with clinical data.

MATERIAL AND METHODS:
168 samples analyzed in Cell Dyn® Sapphire, between March and August 2010, using CBC+RET methodology in the determination of: rP%, reticulocytes % (Ret%), platelet optical counts (PLTo) and mean platelet volume (VPM). Normal control samples (C) n=73; Patients: 20 with auto-immune haemolytic anemia (IHA); 8 with thrombocytopenic thrombotic purpura (TTP); 45 with immune thrombocytopenia (IT), 4 with bone marrow aplasia (BMA) and 18 thrombocythopenias of unknown cause (TUC). Mean difference between rP% in controls vs TUC samples calculated by t-student. Statistical analysis by StatView 5.0.

RESULTS:
C samples: median rP % =1.6, range=0.2-4.1, mean PLTo= 263×109/L, median MPV=8.5fL. IHA: median rP%= 1.9, range =0.6 – 12.5, mean PLTo=284×109/L, median MPV= 8.6, mean Ret%=12. TTP: median rP%=5.1, range=0.3-16.5, mean PLTo=185×109/L, median MPV=8.5. IT: median rP%=3.8, range=0.4-27.8, mean PLTo=56.8×109/L, median MPV=11.4. BMA: median rP%=4.1, range=0.3-6, mean PLTo=66.2×109/L, median MPV=11. TUC: median rP%=2.7, range=0.2-13.6, mean PLTo= 80.5×109/L, median MPV=11.1 Mean difference between rP% in C vs TUC samples: t=2.5, p=0.02.

CONCLUSIONS:
Median rP% values obtained in control group are in agreement with published data, despite the variation in the “normal” values between the authors. MPV and rP% in destructive thrombocytopenias (IT and TTP) are higher than in control group, in accord to immature platelets release by the bone marrow. IHA patients, despite the high Ret%, have a median rP% similar to the control group, demonstrating that rP counts are not over-estimated by the high number of reticulocytes. In BMA rP% is higher than expected, however the number of samples analyzed is very low. The statistically significant mean difference between rP% in Control vs TUC samples makes the immune cause for the thrombocytopenia very likely. Due to its simplicity, ready availability and information provided by this methodology, it has a good potential to be a useful tool in the investigation of thrombocytopenias of unknown cause.

Disclosures:
No relevant conflicts of interest to declare.
Rituximab Is An Effective Therapy for Relapsed Thrombotic Thrombocytopenia Purpura
Authors: Jajeh Ahmad 
Published: October 2019

Abstract
Abstract 4679
Rituximab, a monoclonal antibodies designed against a CD20 glycoprotein expressing lymphocytes. This drug has been implemented in the treatment of B Cell lymphoproliferative disorders as well as other non-neoplastic diseases such as autoimmune disorders. Rituximab has produced response in auto-immune thrombocytopnea, auto-immune hemolytic anemia and refractory inhibitors to coagulation factors. This abstract present our experience with rituximab in the treatment of relapsed Thrombotic Thrombocytopenia Purpura and Hemolytic Uremic Syndrome TTP/HUS. A total of five patients diagnosed with relapsed TTP/HUS with mean age of fifty years, all are black females. Median time to relapse is 5 months, range from 3 weeks to two years. All patients were treated initialy with plasmaphoresis and steroids, average plasmaphoresis treatment before relapse is seventeen sessions, range twelve to twenty five. All patients were retreated with plasmaphoresis and steroids at relapse and all received Rituximab weekly therapy, range two doses to six. All patient achieved good response and durable remission with out relapse. Dose used is 375 mg/M2. Peripheral smears were monitored on daily bases, same as CBC, LDH, BUN and creatinin. Most interestingly that red cell fragmentation were significantly reduced after one week of starting rituximab. Fragmented red cell/schiztocytes were reduced to 3 schiztocytes per 5000 red cell on high power field light microscope. Most patient received first dose of rituxan after at least seven to nine sessions of plasmaphoresis given.
In conclusion: Rituximab is an effective therapy in relapsed TTP/HUS, larger study needed to confirm efficacy. Consideration to give Rituximab in first line therapy as well as maintenance therapy is a valid point.

Disclosures:
No relevant conflicts of interest to declare.
Patrolling Murine Monocytes Are Defined by Their Expression of the Orphan Nuclear Receptor, Nur77 (nr4a1)
Authors: Hubbeling Harper , Maltzman Jonathan , Moran Amy , Hogquist Kristin , Cunningham Nicole , Punt Jenni A. 
Published: October 2019

Abstract
Abstract 4723
‘Resident’ or ‘patrolling’ monocytes have recently been described as a unique subset of myeloid cells that differ in phenotype and function from classic inflammatory monocytes. Resident monocytes are distinguished by their ‘crawling’ migration on endothelial surfaces, their immunosuppressive activity, and their unique pattern of surface protein expression: Ly6Clo, CX3CR1hi, CCR2-, LFA-1+, and PDL-1+. Using a Nur77-eGFP reporter mouse, we show that all murine patrolling monocytes, but not conventional monocytes express Nur77+ (also known as NR4A1), a member of the Nur orphan nuclear receptor family that regulates cell fate decisions several cell types and inhibits leukemogenesis. Nur77 is an immediate early response gene, and we have recently determined that it is a sensitive indicator of antigen receptor signaling among T cells. We therefore propose that its expression among patrolling monocytes is an indication that these cells are actively receiving signals, perhaps via interactions with the endothelium. We are currently working to identify these signals and our preliminary data suggest that adhesion molecules play an influential role.
We thank the Arnold and Mabel Beckman Foundation (HH), and NSF (MCB-0744570 (JP and NC)) for their support for this work.

Disclosures:
No relevant conflicts of interest to declare.
Learn While You Wait: An Experience of a Novel, Interactive VHA e-Notebook Education Program for Multiple Myeloma
Authors: Yacoub Abdulraheem , Mehta Paulette 
Published: October 2019

Abstract
Abstract 4743
We evaluated a novel e-notebook -based education program for patients with multiple myeloma. The program was developed by the Myeloma Initiative in the Veteran's Administration (MIVA) consortium to educate patients while they wait for clinic appointments or procedures. The goals of this study were to assess feasibility of the program in a busy clinic setting, patients’ gain in knowledge from the program, patients’ acceptance of the e-notebook format, and potential use of program in other populations and in different formats. Study subjects were patients with multiple myeloma being treated at the Central Arkansas Veterans Healthcare System McClellan Hospital. Eligibility criteria were diagnosis of multiple myeloma, ability to follow instructions in the program and complete a paper questionnaire. Study subjects underwent the program while awaiting their oncology visit and then completed a survey consisting of ten multiple-choice questions designed to measure the goals of the study. The scope of the questions were: patients’ perceived benefit of the education program in improving their understanding of their disease (three questions), patients’ primary source of medical education, patients’ preferences in regard to educational formats (three questions), and multiple myeloma knowledge (three questions). Program use did not adversely affect patient flow in our busy oncology clinic, and was well accepted by the patients. Eight patients were enrolled in the study. All patients considered their oncologist to be their primary source of information about their disease. All patients stated that the education program helped them better understand the information provided by their oncologists and better understand multiple myeloma treatment options. Five patients (63%) answered that the program motivated them to learn more about myeloma. Seven patients (88%) recommended that this program be expanded to spouses or family members, and seven patients (88%) advocated creating a video format of the program for repeat viewing. Five patients (63%) stated they plan to view the content again at a later time. Of all multiple myeloma knowledge questions, 71% were answered correctly and 50% of the patients attributed their correct answers to information they learned in the education program. We conclude that this e-notebook -based multiple myeloma education program is well accepted, can be adopted in a busy clinic and has the potential for further applications. It is an effective and motivating tool for patient education in adjunct with physician efforts. It can be a productive utilization of waiting room time.

Disclosures:
No relevant conflicts of interest to declare.
IDENTIFICATION of Infrared SPECTRAL Signature of INDUCED Pluripotent STEM CELLS (iPSC)
Authors: Sandt Christophe , Feraud Olivier , Turhan Ali G. , Dumas Paul , Bennaceur-Griscelli Annelise 
Published: October 2019

Abstract
Abstract 4792
Recent technological advances in cell reprogramming by generation of induced pluripotent stem cells (iPSC) offer major perspectives in disease modelling and future hopes for providing novel stem cells sources in regenerative medicine. However, research on iPSC still requires refining the criteria of the pluripotency stage of these cells and exploration of their equivalent functionality to human embryonic stem cells (hESC). In this work, we report that the use of the Synchrotron-based FTIR microspectroscopy allows following the infrared spectral modification of the differentiated cells during the reprogramming process as well as the comparison between iPSC with hESC. The model that we studied consisted on the use of human ES cell line H9 grown on murine embryonic fibroblasts in the presence of bFGF. We have generated mesenchymal stem cells from the H9 cell line (H9-MSC) and we used them to generate iPSC (iPSC-H9) by the enforced expression of pluripotency genes Oct4, Sox2, Lin28 and Nanog. We have also followed the same approach on murine cells by generating murine iPSC from murine ES cells by retrovirus mediated gene transfer of Oct4, Sox2, c-Myc and Klf4. iPSC were characterized by expression of pluripotency markers, and teratoma assays. Infrared Spectral fingerprints of the original H9, MSC-H9 and iPSC-H9 as well as differentiated murine fibroblasts and murine iPSC were acquired at sub-cellular resolution using a synchrotron-powered infrared microscope. In murine system, the spectral signature of iPSC has been compared to that of D3, a well-characterized murine ES cell line. The spectral signature of iPSC and ESC displays a marked difference with those of the differentiated cells used before reprogrammation regardless the origin of the target cell (mesenchymal stem cells or murine fibroblasts). We unambiguously demonstrate for the first time to our knowledge, that the human and murine iPSC retrieve the same chemical composition with an indistinguishable spectral signature from their embryonic stem cells counterparts. Importantly, the spectral signatures were found to be specific to each of the cell line, as evidenced using pattern recognition methods and illustrated the genetic biodiversity of each iPSC and ESC. Thus, in addition to the classical pluripotency markers, FTIR microspectroscopy signature could be a rapid methodology to evaluate the pluripotency after somatic cell reprogramming.

Disclosures:
No relevant conflicts of interest to declare.