bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneous Interactions of Leukemic and Control Bone Marrow Stroma Cells with an AML Cell Line and AML Leukemic Blasts.
Authors: Buttkereit Ulrike , Mohamad Sana , Lindemann Monika , Goethert Joachim R. , Opalka Bertram , Duerig Jan , Duehrsen Ulrich 
Published: October 2019

Abstract
Abstract 1047
Tumor-stroma interaction plays a pivotal role for malignant cell survival, proliferation, immune escape, and drug resistance. We had previously shown that bone marrow (BM) stroma from leukemia patients had different gene expression patterns and support of normal CD34+ cells compared to controls (Ctr). Aim of this study was to evaluate growth, survival, and colony-forming potential issues of M-07e AML cells and AML blasts as indicator cells (IC) upon contact with non-leukemic and leukemic stroma. Plastic-adherent BM cells from leukemic or Ctr non-leukemic donors were cultured for several weeks. Polyclonal as well as isolated single fibroblast colony (F-CFU) cultures were set up. Short-term and long-term co-cultures of BM stroma used M-07e AML cells and AML blasts as IC. After long-term co-culture colony forming units (CFU) were determined in the adherent and non-adherent fraction of the IC. Proliferation of IC was determined by cell counting and 3H-TdR incorporation assays. The human HS-5 stroma cell line was used in selected experiments. The F-CFU frequency was determined from 39 Ctr samples, 6 MDS samples, 59 leukemic samples, and 12 lymphoma samples with BM infiltration. Succession of F-CFU numbers in respective samples was AML / MDS < Ctr < MM / FL II << 2°AML. Polyclonal stroma cells from AML BM supported M-07e IC survival slightly but not significantly better than Ctr stroma. No noteworthy support for primary AML blasts was observed with either stroma. Stroma from both AML and Ctr donors stimulated colony formation of M-07e IC without marked differences in the frequency of compact and diffuse colonies. In 3H-TdR assays M-07e IC were stimulated by IL-3 and certain but not all stroma samples tested. Notably, IL-3-induced proliferation of M-07e IC was decreased in the presence of stroma and almost completely suppressed by HS-5 cells. When single F-CFU were isolated, expanded, and tested for their capacity to support M-07e IC stimulating as well as non-stimulating F-CFU were found. Support competence of stroma cells decreased with passage number. Primary BM polyclonal stroma cells and single F-CFU from leukemic and non-leukemic donors showed a broad heterogeneity with respect to support of cell growth or colony-forming potential in favour of the AML M-07e IC line. Thus, the interaction of stroma and normal or leukemic hematopoietic cells seems to be a complex system awaiting further investigations.

Disclosures:
No relevant conflicts of interest to declare.
Micafungin Versus Voriconazole for Empirical Antifungal Therapy In Febrile Neutropenic Patients with Acute Myeloid Leukemia: A Randomized, Controlled Trial.
Authors: Oyake Tatsuo , Kowata Shugo , Murai Kazunori , Ito Shigeki , Akagi Tomoaki , Kubo Koumei , Sawada Kenichi , Ishida Yoji 
Published: October 2019

Abstract
Abstract 1062

Background:
Invasive fungal infections (IFIs) incur significant morbidity and mortality among neutropenic patients after chemotherapy. The risk for these infections is related to the intensity and duration of neutropenia, and varies from 2% to 40%. Mortality rates associated with documented IFIs are considerable, reportedly ranging from 30% to 60%. Empirical antifungal therapy is the standard care for neutropenic patients with hematological malignancies who remain febrile despite broad-spectrum antibacterial treatment. Several antifungal agents including voriconazole (VRCZ) or liposomal amphotericin B (L-AMB) have been studied as empirical therapy for febrile neutropenia (FN). However, limited data are available concerning the efficacy of micafungin (MCFG) in FN patients with acute myeloid leukemia (AML).

Methods:
We conducted a randomized, cooperative group, open-label trial comparing MCFG (150 mg once daily) with VRCZ (6 mg/kg twice on day 1 followed by 4 mg/kg twice daily) as first-line empirical antifungal treatment for 95 hospitalized FN patients with AML during induction or consolidation chemotherapy (MCFG, 49; VRCZ, 46). The efficacy end point was a favorable overall response, as determined by a five-component end point according to the criteria of Walsh et al (N Engl J Med 2004; 351: 1391).

Results:
At the time of enrolment, there were no significant differences in the demographics or baseline characteristics between the two groups. The mean treatment duration for MCFG and VRCZ was 10 and 9 days, respectively. The efficacy rates of MCFG and VRCZ were not significantly different (37.8% vs. 32.4%). The rates of breakthrough fungal infections (proven, probable and possible IFIs), successful treatment of baseline fungal infections, survival 7 days after end of therapy, and resolution of fever during neutropenia were similar in the two groups. However, premature discontinuation of therapy occurred less often in the MCFG group than in the VRCZ group (32.4% vs. 55.9%, P=0.0457*). In safety evaluation, there were fewer adverse events in the MCFG group than in the VRCZ group (27.0% vs. 64.7%, P=0.0013*). *: Chi square test

Conclusions:
MCFG was as effective as VRCZ, and better tolerated than VRCZ as empirical antifungal therapy in FN patients with AML.

Disclosures:
No relevant conflicts of interest to declare.
An Open Label, Non Randomized, Propspective Phase IV Clinical Trial Evaluating the Immunogenicity of Branded Enoxaparin Versus Biosimilars In Healthy Volunteers.
Authors: Gomes Marise , Ramacciotti Eduardo , Hoppensteadt Debra , Walenga Jeanine M. , Lewis Bruce E , Jeske Walter , Fareed Jawed 
Published: October 2019

Abstract
Abstract 1086
Biosimilar enoxaparin preparations are in use outside the U.S. Due to compositional variations, their interaction with platelet factor 4 (PF4) differs leading to differential immunogenic responses between branded and biosimilar agents. To compare their immunogenic response, branded enoxaparin (Clexane®, Sanofi-Aventis) and a biosimilar version (Cutenox®, Gland-Pharma) were administered to healthy volunteers (n=110/drug) at a dose of 40 mg SQ for10 days. Blood samples drawn on days 1 and 10 were analyzed for anti-heparin/PF4 antibody (A-HPF4-Ab) titers and subtypes by ELISA (GTI, Brookfield, WI). Treatment with each LMWH resulted in comparable A-HPF4-Ab generation as compared by using the total absorbance for each population (p<0.05). However in the thrombin generation assays clexane group showed a stronger inhibition (45+12% vs 32+9%). None of these antibodies activated platelets as determined by the serotonin release assay. The two groups alos showed comparable AXa and AIIa responses (p<0.05). Antibody subtyping demonstrated different profiles between LMWHs. For IgG (Clexane1=0.15±0.04, Clexane10=0.21±0.06, Cutenox1=0.17±0.04, Cutenox10=0.28±0.10) with a significant time effect (p<0.0001), a significant drug effect (p<0.0001), and a significant time by drug interaction (p=.0009). Post hoc comparisons showed a difference between the drugs at time 0 (p=0.03), a difference between the drugs at time 10 (p<0.0001) and a significant time effect for each drug (p<0.0001). For IgA (Clexane1=0.12±0.02, Clexane10=0.15±0.02, Cutenox1=0.12±0.03, Cutenox10=0.13±0.02) with significant effects for time (p<0.0001), drug (p=0.0078) and for the drug × time interaction (p<0.0001). The post hoc comparisons showed a significant drug effect at time 10 (p<0.0001). There was a significant time effect for Clexane (P<0.0001) but not for Cutenox. For IgM (Clexane1=0.11±0.01, Clexane10=0.13±0.02, Cutenox1=0.11±0.03, Cutenox10=0.13±0.02), there was only a time effect (p<0.0001). The post hoc comparisons showed no difference between drugs at either time, but significant time effects for each drug (p<0.0001). The immunogenic potential of LMWHs varies in terms of ability to generate A-HPF4-Ab, the antibody subtypes generated, and their cross-reactivity with pre-formed A-HPF4-Ab. Such parameters may be useful in defining the bioequivalence of generic LMWHs. Future studies evaluating the immunogenicity of different compounds in patients exposed to biosimilar drugs are warranted.

Disclosures:
Jeske: PolyMedix, Inc.: Research Funding.
What Is the Best Time to Initiate Peri-Operative Heparin Therapy In General Surgery Patients? A Risk-Benefit Dilemma.
Authors: Rostambeigi Nassir , Greenlee Susan , Huebner Marianne , Farley David 
Published: October 2019

Abstract
Abstract 1088

Background:
While many studies support the use of prophylactic heparin therapy around the time of operation in cancer patients, little data shows the optimal timing of such therapy in general surgery (GS) patients.

Methods:
From 2001–2008, 95 patients identified with thromboembolism reported in our GI/General Surgery Division and were compared with a matched control group for: age, gender, type of operation, date of operation, diagnosis of malignancy, and BMI. Timing of heparin therapy, characteristics of TE or bleeding events, driving distance from our institution, history of smoking or OCP use, anticoagulation use after operation, length of hospital stay, and mortality were collected. Peri-operative heparin therapy was defined as heparin given within a 24 hr window of incision. The McNemar's test for proportions was performed. Conditional logistic regression was used for the analysis of risk factors and survival curves were implemented for mortality comparisons.

Results:
mean age and BMI were similar (57 yrs, 33 kgM-2), 45% were female and 53% had malignancy in both groups. Duration of operation was similar (204 vs. 191 minutes, P=NS). peri-operative heparin administration was similar in the two groups (56%, 64%, p=0.05). But, pre-operative therapy was seen more in the control group (77% vs. 51%, p=0.01). Regression model showed a protective effect for heparin if it was given pre-operatively (OR=0.37, p=0.047) with no effect if it was given beyond 10 hours. Mean blood transfusion units (97 and 106 mL) and hemorrhagic events (4.5% and 5%) were similar (p=NS). Median (range) length of hospital stay was longer (19 days (0-201) vs. 6 (0-66), p=0.001) and two-year survival lower in the TE group (p=0.03).

Conclusions:
data from our institutional case-control study shows that heparin administration before GS is associated with more than 2-fold reduction in the risk of thromboembolism. The optimal period appears to be between 1–10 hours prior to the time of incision. Large prospective trials need to be desgined to more accurately determine the time of heparin therapy.

Disclosures:
No relevant conflicts of interest to declare.
Prothrombin Complex Concentrate Reverses the Anticoagulant Effect of Rivaroxaban In Healthy Volunteers.
Authors: Eerenberg Elise S , Sijpkens Meertien K , Kamphuisen Pieter W , Meijers Joost CM , Levi Marcel 
Published: October 2019

Abstract
Abstract 1094

Background:
Rivaroxaban is a novel oral antithrombotic agent in the class of specific factor Xa inhibitors, and is licensed in Europe and Canada for the prevention of venous thromboembolism after elective orthopedic surgery. Despite its stable pharmacokinetic and pharmacodynamic profile, immediate reversal may be required in case of a major bleeding or emergency surgery. No specific antidote is currently available, although Prothrombin Complex Concentrate (PCC) seems effective in animal studies. This study is the first to investigate the ability of PCC to reverse the antithrombotic effect of Rivaroxaban in humans.

Methods:
In a randomized, double-blind, placebo-controlled trial, twelve healthy male subjects received Rivaroxaban 20mg twice daily for two and a half days. One group (n=6) was then randomized to receive a single bolus of 50 IU/kg PCC (Co-fact®, Sanquin, the Netherlands) while the other group (n=6) was given a similar volume of saline.

Results:
The prothrombin time (PT) was significantly prolonged by Rivaroxaban (15.8 sec ± 1.3 versus 12.3 ± 0.7 at baseline; p< 0.001). Immediately after the infusion of PCC, the PT normalised almost completely (12.8 ± 1.0; p< 0.001), which was sustained for 24 hours. Saline did not reverse the PT prolongation (16.2 ± 0.8; p= 0.4). Furthermore, Rivaroxaban inhibited the endogenous thrombin potential (ETP) (51% ± 22, baseline 92 ± 22; p= 0.002), with normalisation after administration of PCC (114 ± 26; p< 0.001), but not after saline (41 ± 6; p= 0.2).

Conclusions:
This study provides the first data that Prothrombin Complex Concentrate reverses the anticoagulant effect of Rivaroxaban in humans and may serve as an antidote for the new oral factor Xa inhibitors.

Disclosures:
Eerenberg: Sanquin Netherlands: Research Funding, make available of Prothrombin Complex Concentrate for this study. Kamphuisen:Sanquin Netherlands: Research Funding, make available of Prothrombin Complex Concentrate for this study. Levi:Sanquin Netherlands: Research Funding, make available of Prothrombin Complex Concentrate for this study.
Predictors of the Indefinite-Duration Anticoagulation Treatment Strategy In Patients with Cancer-Associated Thrombosis.
Authors: Spirk David , Korte Wolfgang , Husmann Marc , Frauchiger Beat , Banyai Martin , Aujesky Drahomir , Baumgartner Iris , Kucher Nils 
Published: October 2019

Abstract
Abstract 1097

Background:
In patients with cancer and acute venous thromboembolism (VTE), current consensus guidelines recommend anticoagulation therapy for an indefinite duration or until the cancer is resolved.

Methods and results:
Among 1’247 patients with acute VTE enrolled in the Swiss Venous Thromboembolism Registry (SWIVTER) from 18 hospitals, 315 (25%) had cancer of whom 179 (57%) had metastatic disease, 159 (50%) ongoing or recent chemotherapy, and 83 (26%) tumor surgery within 6 months. Patients with cancer were older (66±14 vs. 60±19 years, p<0.001), more often hospitalized at the time of VTE diagnosis (46% vs. 36%, p=0.001), immobile for >3 days (25% vs. 16%, p<0.001), and more often had thrombocytopenia (6% vs. 1%, p<0.001) than patients without cancer. The 30-day rate of VTE-related death or recurrent VTE was 9% in cancer patients vs. 4% in patients without cancer (p<0.001), and the rates of bleeding requiring medical attention were 5% in both groups (p=0.57). Cancer patients received indefinite-duration anticoagulation treatment more often than patients without cancer (47% vs. 19%, p<0.001), and LMWH mono-therapy during the initial 3 months was prescribed to 45% vs. 8%, p<0.001, respectively. Among patients with cancer, prior VTE (OR 4.0, 95%CI 2.0–8.0), metastatic disease (OR 3.0, 95%CI 1.7–5.2), outpatient status at the time of VTE diagnosis (OR 3.8, 95%CI 1.9–7.6), and inpatient treatment (OR 4.4, 95%CI 2.1–9.2) were independently associated with the prescription of indefinite-duration anticoagulation treatment.

Conclusions:
Less than half of the cancer patients with acute VTE received a prescription for indefinite-duration anticoagulation treatment. Recurrent VTE, metastatic cancer, outpatient VTE diagnosis, and VTE requiring hospitalization were associated with an increased use of this strategy.

Disclosures:
Spirk: sanofi-aventis (suisse) sa: Employment.
Thrombin Activation of Protease-Activated Receptor-2 on Neutrophils Primes the Respiratory Burst.
Authors: Bock Ashley , Kelher Marguerite , Khan Samina , Hansen Kirk , Dzieciatkowska Monika , Silliman Christopher C 
Published: October 2019

Abstract
Abstract 1119
Thrombin is a multifunctional serine protease involved in hemostasis, fibrinolysis, and pro-inflammatory activation of innate immunity through stimulation of protease-activated receptors (PARs). Thrombin is considered the prototypical protease to activate PARs through cleavage of the N-terminal exodomain of the receptor, thereby unmasking a tethered ligand which activates it. Neutrophils (PMNs) are reported to express PAR-2; however, little is known about the changes in PMN physiology following protease activation of PAR-2. In addition, proteomic analyses (two dimensional gel electrophoresis and mass spectroscopy (MALDI-TOF)) of injured patients (blunt trauma) who developed acute lung injury (ALI) and multiple organ failure (MOF) have identified a number of serine proteases which accumulate post-injury. Moreover, these identical proteases were also found via proteomics in stored, but not fresh, packed red blood cells, which are used to resuscitate these injured patients. We hypothesize that thrombin primes PMNs through activation of PAR-2. Methods: PMNs were isolated from whole blood drawn from healthy human donors using dextran sedimentation, ficoll-hypaque gradient centrifugation and hypotonic lysis of red blood cells. The proteins from whole cell lysates were separated by SDS-polyacrylamide electrophoresis, transferred to nitrocellulose and immunoblotted with a monoclonal antibody to PAR-2. The PMNs were also incubated for 3–30 minutes at 37°C with thrombin [1-10 U/ml] followed by fMLP [1 μM] activation of the NADPH oxidase. Oxidase activity was measured by the superoxide dismutase-inhibitable reduction of cytochrome c at 550 nm. Results: PMNs express PAR-2 as detected by western blotting of whole cell lysates. Thrombin [1 U/ml] for 30 min, significantly primed the fMLP-activated respiratory burst: buffer control: 1.6 +/− 0.5 vs. 1 U/ml thrombin: 2.2 +/− 0.3* (*p<.05, n=5). Higher concentrations of thrombin or shorter incubation times did not induce PMN priming. Furthermore, pre-incubation with leupeptin [50 μM] and 4-(2-Aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF) [250 μM], two effective protease inhibitors, abrogated the thrombin-induced PMN priming by 100±18%. We conclude that thrombin primes the PMN respiratory burst, which is dependent upon its protease activity. Because PMNs are the effector cell in ALI/MOF and priming agents have been linked to the development of clinical ALI and MOF, proteases that accumulate in the patient plasma post-injury or are transfused with stored PRBCs may be etiologic in post-injury ALI/MOF.

Disclosures:
No relevant conflicts of interest to declare.
Is Transfusion of Rh Positive Red Blood Cells to ccDee Patients From a Cosmopolitan Population Safe?.
Authors: Vandeput Marie-Helene , Latinne Dominique , Gervais Thibaut , Eeckhoudt Stephane L 
Published: October 2019

Abstract
Abstract 1121

Introduction:
D variant is a common phenotype in Africans. However, the allele multiplicity challenges the serological methods which often fail to detect D variant patients in such populations. Recently, two cases of strong anti-D allo-immunization occurred in our blood bank in ccDee patients who received transfusions with Rh positive red blood cells. The D phenotype of these patients was determined using two different monoclonal and one polyclonal anti-D antibodies, with normal agglutination (4+) observed. Considering these results, we decided to investigate the prevalence of D variant for the ccDee patients of our cosmopolitan population. The aim of this study was to determine whether ccDee blood recipients should systematically undergo molecular screening for D variant prior to transfusion in order to avoid anti-D allo-immunization.

Materiel and methods:
Fresh EDTA blood from 35 ccDee patients (22 Africans and 13 Europeans) was analyzed using both serological and molecular methods. Serological characterization was performed using two monoclonal and one human polyclonal anti-D antibodies. In addition, each sample was tested using an extended partial RhD typing set from Diamed (consisting of 12 monoclonal antisera). Molecular determination was performed using two polymerase chain reactions with sequence-specific priming (PCR-SSP) kits intended to diagnose either partial D or weak D phenotypes (BAGene, BAG, Lich, Germany).

Result:
Among the 35 patients screened, discordant results between serological and molecular methods were found in 12. While serological tests revealed a normal D phenotype for these patients with all anti-D antibodies tested, molecular tests diagnosed them as D variant (nine were DAU; two were weak D types 4.0 and 4.1; one was DAR). As expected, the vast majority (9/12) of these patients were of African descent. No discordance between serological and molecular screening was observed for the rest of the screened population (23 patients).

Conclusion:
Our study reveals that approximately one-third (12/35) of our ccDee patients present a D variant genotype despite normal serological results. It emphasizes the fact that transfusion of Rh positive red blood cells to ccDee patients (mainly of African origin) requires precautionary measures. Molecular D variant screening in ccDee patients should be performed in order to improve the handling of transfusions in ccDee patients.

Disclosures:
No relevant conflicts of interest to declare.
Carbon Monoxide-Releasing Molecule-Derived CO Regulates Tissue Factor, Plasminogen Activator Inhibitor Type 1, and Thrombomodulin Production by Human Endothelial Cells.
Authors: Maruyama Keiko , Morishita Eriko , Ohtake Shigeki , Yachie Akihiro , Nakao Shinji 
Published: October 2019

Abstract
Abstract 1146

Background and purpose:
Heme oxygenase-1 (HO-1) is a cytoprotective and anti-inflammatory protein that catalyzes the conversion of heme into biliverdin, free iron, and carbon monoxide (CO). HO-1 is rapidly induced by various oxidative stresses and inflammation, thereby playing an important role in the self defence system. Recently, Yachie, et al. reported the first human case of HO-1 deficiency. This patient showed prominent signs of intravascular hemolysis, endothelial cell injury, and abnormalities in the coagulation / fibrinolysis system, suggesting the involvement of HO-1 or HO-1 products, such as CO, regulation of coagulation / fibrinolysis system. The current study examined whether tricarbonyldichlororuthenium (II) dimer (CORM-2), which liberated CO in the presence of dimethyl sulfoxide (DMSO), modulates the expression of tissue factor (TF), plasminogen activator inhibitor type 1 (PAI-1) and thrombomodulin (TM) in human umbilical vein endothelial cells (HUVECs).

Methods:
HUVECs were pretreated with CORM-2 at the concentration of 50 μM for 3h, washed and stimulated with tumor necrosis factor-α(TNF-α, 10 ng/ml) for additional 2 or 5h. The mRNA and protein levels of TF, PAI-1 and TM in the cultured HUVECs were determined by real-time reverse transcriptase polymerase chain reaction and Western blotting. To determine whether CORM-2 affects the MAPK signaling pathways, the phosphorylation of p38 mitogen-activated protein kinase (p38MAPK) and extracellular signal-regulated kinase1/2 (ERK1/2) in the HUVECs were analyzed with Western blotting.

Results:
After TNF-α stimulation, TF mRNA levels were approximately 6-fold and PAI-1 mRNA levels were approximately 8-fold increased, and TM mRNA levels were decreased by 20% compared to the control. Similarly to the mRNA expression, TF and PAI-1 protein levels were increased while the TM protein level was decreased. On the other hand, pretreatment of HUVECs with CORM-2 significantly decreased TF mRNA levels (approximately 80% suppression), and PAI-1 mRNA levels (approximately 90% suppression) while increased TM mRNA levels by 3-fold as compared to the TNF-α-stimulated group (p<0.05; Figure 1). Similarly, the pretreatment with CORM-2 inhibited TNF-α-induced TF and PAI-1 protein up-regulation and TM protein down-regulation. CORM-2 inhibited TNF-α-induced activation of p38MAPK and ERK1/2 by 50% compared to the control.

Conclusions:
These results indicate that CO liberated by CORM-2 suppresses the TNF-α-induced TF and PAI-1 up-regulation and prevents the TNF-α-induced TM down-regulation in HUVECs via MAPK signaling pathways. Thus, the modulation of endothelial function by CO may offer a novel antithrombotic option for treatment of the hypercoagulable state associated with inflammation.

Disclosures:
No relevant conflicts of interest to declare.