bluuebunny/crossref_metadata_2025_split huggingface dataset:
Platelet Inhibition by Adjunctive Cilostazol Versus High Maintenance-Dose Clopidogrel In Patients with Acute Myocardial Infarction According to Cytochrome P450 2C19 Genotype
Authors: Kim In-Suk , Jeong Young-Hoon , Kim Arum , Lee Gyeong-Won 
Published: October 2019

Abstract
Abstract 3322

Objectives
The aim of this study was to assess the degree of platelet inhibition by adjunctive cilostazol in patients with acute myocardial infarction (AMI) according to CYP2C19 genotype.

Background
Although adjunctive cilostazol intensifies platelet inhibition in AMI patients, it is not established whether this regimen can overcome the loss-of-function effect of CYP2C19 variants.

Methods
We randomly assigned 126 AMI patients with available CYP2C19 genotyping to receive adjunctive cilostazol (triple group; n = 64) or high maintenance-dose (MD) clopidogrel of 150-mg/day (high-MD group; n = 62). Using conventional aggregometry and VerifyNow, platelet reactivity was measured at pre-discharge and 30-day follow-up. Primary endpoint was change in maximal platelet aggregation (Aggmax). High post-treatment platelet reactivity (HPPR) was defined as 5 μmol/l ADP-induced Aggmax > 50%.

Results
In non-carriers, the two groups did not differ with respect to changes in platelet measures, and could achieve fewer rates of HPPR at 30-day follow-up (< 5%). In carriers, changes in 5 and 20 μmol/l ADP-induced Aggmax were significantly higher in the triple (n = 39) versus high-MD group (n = 38) (21.8 ± 13.9% vs. 9.0 ± 13.3%, p < 0.001, and 24.2 ± 17.2% vs. 7.7 ± 15.5%, p < 0.001, respectively). Likewise, changes in late platelet aggregation and P2Y12 reaction unit were consistently greater in the triple vs. high-MD group. Fewer patients in the triple group met the criteria of HPPR at 30-day follow-up compared with the high-MD group (2.6% vs. 21.1%, p = 0.014).

Conclusions
Among AMI patients with CYP2C19 variants, adjunctive cilostazol enhances platelet inhibition and reduces the rate of HPPR, as compared with high-MD clopidogrel. (Adjunctive Cilostazol Versus High-MD ClopidogrEL in Patients With Acute Myocardial Infarction According to CYP2C19 genotype [ACCEL-AMI-CYP2C19]; NCT00915733).

Disclosures:
No relevant conflicts of interest to declare.
Inhibition of Thrombin Generation: An Additional Biological Criterion for the Evaluation of the Anticoagulant Mechanism of Action of Generic LMWHs
Authors: Gerotziafas Grigoris T , Sassi Mouna , Galea Vassiliki , Fareed Jawed , Walenga Jeanine M. , Elalamy Ismail 
Published: October 2019

Abstract
Abstract 3334

Background.
All low molecular weight heparins (LMWHs) exert their antithrombotic effect primarily via the binding of pentasaccharide domain on antithrombin but vary in physicochemical properties, anti-Xa/anti-IIa ratios, and their effect on global coagulation tests such as the inhibition of thrombin generation (TG). Definition of criteria for biological similarity between generic LMWHs and the original product is a challenging issue.

Aim of the study.
We evaluated the capacity of Lovenox® and seven generic enoxaparins to inhibit TG in platelet poor and platelet rich plasma (PPP and PRP).

Materials and Methods.
Citrated PPP and PRP from 15 healthy volunteers was spiked with increasing concentrations (2-20 μg/ml) of Lovenox®, Novex®, Enoxa®, Dilutol®, Versa®, Cutenox®, Loparin®, Fibrinox®. Platelet count in PRP was adjusted to 200 /L. The anti-Xa and anti-IIa activities in PPP were measured on STAR analyser using chomogenic assays from Diagnositca Stago. Thrombin generation in fresh PPP and PRP was triggered with PPP-reagent® and 1/200 diluted Innovin® (from Siemens) respectively and assessed with Calibrated Automated Thrombogram® (Stago, France). Mean Rate Index (MRI) of the propagation phase of TG and endogenous thrombin potential (ETP) were analysed. The enoxaparin concentrations which reduced 50% of theTG parameters (IC50) were calculated.

Results.
All studied compounds showed the same anti-Xa activity/mg and anti-Xa/anti-IIa ratio as the comparator Lovenox®. The IC50 for MRI and ETP in PPP was not significantly different between Lovenox® and each one of the generic enoxaparins. In PRP the IC50 of Lovenox® for MRI and ETP was significantly lower compared to the generic enoxaparins. The IC5O of Fibrinox®, Dilutol®, Cutenox® and Versa® was 1.5- to 2-fold higher compared to that of Lovenox® (Table 1).

Conclusion.
Lovenox® and seven generic enoxaparins were the same in terms of anti-Xa activity/mg and anti-Xa/anti-IIa ratio. They exerted similar inhibitory effect on thrombin generation in PPP. In contrast, in the presence of platelets, the sameness and even the biological similarity of the studied compounds are not evident. The reasons for these diversities need to be elucidated. The results of the present study introduce the inhibition thrombin generation in platelet rich plasma as an additional biological criterion for the comparison of generic LMWHs to the innovator product.

Disclosures:
No relevant conflicts of interest to declare.
Platelet-Targeted Pro-Urokinase as a Novel Thromboprophylaxis Fibrinolytic Strategy
Authors: Fuentes Rudy , Kowalska M. Anna , Tliba Samira , Bougie Daniel W. , Aster Richard H. , Cines Douglas B. , Muzykantov Vladimir R. , Poncz Mortimer , Zaitsev Sergei 
Published: October 2019

Abstract
Abstract 3339
Use of plasminogen activators (PAs) is restricted to life-threatening thrombotic conditions because high concentrations are required to diffuse into clots, overcome PA inhibitors and compensate for rapid clearance, thereby predisposing to bleeding. We hypothesized that targeting pro-PAs to platelets would circumvent these obstacles and preferentially lyse nascent, pathological clots that are actively recruiting platelets, while sparing preformed hemostatic clots. To test this concept, we expressed a chimeric protein (anti-PLT scFv/uPA-T) composed of an N-terminal scFv generated from a monoclonal antibody MoAb 312.8 directed to human αIIb integrin chain linked via a serine-rich linker peptide to human low molecular weight thrombin activatable pro-urokinase (uPA-T) wherein the plasmin cleavage site was replaced with a thrombin cleavage site, which we reasoned would be activated preferentially at sites of active clot propagation. Anti-PLT scFv/uPA-T expressed in Drosophila S2 insect cells bound specifically to human platelets and to transgenic mouse platelets that contain only human αIIb/mouse β3 on their cell surface (HαIIb+ Tg), but not to wild type mouse platelets. The anti-PLT scFv/uPA-T bound specifically to immobilized human αIIbβ3 with a Kd of ∼80 nM. The anti-PLT scFv/uPA-T did not interfere with either ADP-induced platelet aggregation or activation as demonstrated by expression of P-selectin by flow cytometry, and retained its zymogenic properties until activated specifically by thrombin. The fibrinolytic activity of anti-PLT scFv/uPA-T and uPA-T were compared using the FeCl3 carotid artery injury model in HαIIb+ Tg mice. The mice were protected from forming occlusive thrombi for at least 10 hrs post injection of anti-PLT scFv/uPA-T whereas even five-fold higher concentrations of uPA-T were effective for only 2–5 min. These studies support a novel approach for prophylactic targeting drug delivery by combining a pro-drug that requires activation by thrombin with platelet delivery to sites of incipient thrombotic vascular occlusion.

Disclosures:
No relevant conflicts of interest to declare.
Transfusion Transmission of GB Virus Type C (HGV) In a Cohort of HIV Infected Patients
Authors: Vahidnia Farnaz , Petersen Maya , Rutherford George , Busch Michael , Assmann Susan , Stapleton Jack , Custer Brian 
Published: October 2019

Abstract
Abstract 3341

Background:
GB virus type C (GBV-C) infection is common with 3–5% rates of viremia in blood donors and a much higher prevalence in HIV infected patients. GBV-C is transmitted by sexual or blood exposure. Although infection may persist, most immune competent individuals clear viremia within 2 years. Few data describe the clinical course of acute GBV-C infection following transfusion in HIV infected patients. We estimated risk of GBV-C RNA acquisition following transfusion.

Methods:
We used a limited access database from the National Heart Lung and Blood Institute from the Viral Activation Transfusion Study (VATS). A RCT of leukoreduced (LR) vs. non-LR transfusion, VATS collected blood samples from U.S. HIV infected transfusion naïve patients. GBV-C RNA in pre- and post transfusion samples was tested after completion of VATS. GBV-C RNA acquisition up to 120 days post-transfusion was examined in 294 patients who were GBV-C RNA and antibody negative before transfusion. Discrete hazard of GBV-C RNA acquisition as a function of cumulative units transfused was estimated using pooled logistic regression.

Results:
GBV-C RNA was detected in 22 (7.5%) of 294 subjects within 120 days following first transfusion. Viremia was detected within the first 30 days in 12 (4.1%) subjects and between 31 and 120 days in 10 (3.4%) subjects. Median (IQR) follow-up duration and total blood units transfused for subjects who acquired GBV-C RNA or stayed negative were: 88.5 (80-108) and 77.5 (32-100) days; and 4 (2-7) and 4 (2-6) units, respectively (Table 1). Discrete hazard of GBV-C RNA acquisition increased with each additional unit transfused (OR=1.09, 95% CI=1.06, 1.11) (Table 2). In pooled logistic regression models, lower baseline HIV viral load and use of antiretroviral therapy (ART) predicted subsequent GBV-C RNA acquisition after controlling for units of blood transfused. Leukoreduction status was not associated with GBV-C transmission.

Conclusion:
Blood transfusion is associated with significant risk of GBV-C acquisition in HIV infected patients. Establishing evidence for transfusion transmission of GBV-C will allow additional studies on the impact of acute acquisition on the course of HIV infection in co-infected patients.

Disclosures:
No relevant conflicts of interest to declare.
Staphylococcus Aureus Detection In Platelets Using Short Synthetic Peptides Derived From Phage-Displayed Random Peptide Libraries Coupled with Quantum-Dot Nanocrystals
Authors: Rao Shilpakala Sainath , Ketha Krishna Mohan V. , Atreya Chintamani D 
Published: October 2019

Abstract
Abstract 3359

Introduction:
Bacterial sepsis in recipients of transfusion products due to contamination of blood components is an infrequent but serious and potentially a fatal complication. Unlike red cells, platelet concentrates (PC) are stored for up to 5 days at room temperature after collection, which is conducive for bacterial growth. In 42% of the sepsis cases following PCs, the most common bacterial contaminant is Staphylococcus spp. Timely detection of these contaminated units is a public health priority. Although a multitude of bacterial diagnostic tests are available for PCs, still there is a need for developing more sensitive, specific and rapid detection assays. The primary objective of this study is to develop a simple and highly sensitive procedure that facilitates rapid and enhanced detection of bacteria using Staphylococcus aureus as a model for PCs.

Methods:
A commercially available bacteriophage-displayed random 12-mer peptide library was screened against S. aureus. The screening and subsequent sequencing of the phage DNA identified a phage clone containing a coding sequence for 12-amino acid peptide that selectively binds to S. aureus. We assessed the binding specificity and detection sensitivity of the peptide to a panel of six bacteria spiked in platelets (including S. aureus) by dot blot, ELISA and fluorometry. The peptides were further labeled with streptavidin-conjugated fluorescent Nanocrystal quantum-dots (Q-dots) to enhance the sensitivity of the assay.

Results:
The membrane-based dot blot method revealed that the peptide binds specifically to S. aureus. ELISA and fluorometry analysis of spiked platelet samples revealed that the peptide binds to S. aureus at 103 CFU/ml concentrations. By using the peptide-Nanocrystal Q-dot combination (peptide probes), the detection sensitivity was further enhanced. The peptide binding remained relatively constant between pH 5 to 7.5.

Conclusion:
This model system demonstrates that peptides derived from random phage library in combination with Nanocrystal Q-dots facilitate high sensitivity detection of S. aureus. In general, this study provides a proof-of-concept that ‘peptide probes' selected against specific bacteria are useful in detecting and monitoring them in various settings relevant to blood safety and transfusion medicine.
The findings and conclusions in this abstract have not been formally disseminated by the Food and Drug Administration and should not be construed to represent any Agency determination or policy.

Disclosures:
No relevant conflicts of interest to declare.
Involvement of Death-Associated Protein Kinases In DNA Damage Responses of B-ALL Cells.
Authors: Humbert Magali , Medova Michaela , Geering Barbara , Blank-Liss Wieslawa , Simon Hans-Uwe , Fey Martin F. , Zimmer Yitzhak , Tschan Mario P. 
Published: October 2019

Abstract
Abstract 3369
Intact DNA damage response pathways are important for genomic fidelity of cells in order to avoid tumor formation. On the other hand, inhibition of DNA repair provides an important mechanism to enhance the therapeutic efficacy of DNA damaging agents such as gamma-irradiation. Thus, it is important to identify novel players in DNA damage response that might represent novel targets for combination therapies. Death-associated protein kinases (DAPK) are serine/threonine kinases believed to be involved in cell death and autophagy mechanisms, whereby particularly the role of DAPK1 has previously been investigated. The DAPK family is composed of five members: DAPK1, DAPK2 (or DRP-1), DAPK3 (or ZIP kinase), DRAK1 and DRAK2. DAPK1 and DAPK2 share 80% homology in the catalytic domain. Generally, the role of DAPK in DNA damage responses is not well studied. To analyze the role of DAPK1 and DAPK2 in response to gamma-irradiation, we used p53 wild-type REH B-cell acute lymphoblastic leukemia (B-ALL) cells as a model. In response to irradiation, DAPK1 protein expression increased paralleled by an increased of total p53, phospho-Ser20-p53 and p21WAF1/CIP1. DAPK2 expression, however, did not increase. Since upregulation of p21WAF1/CIP1, a classical p53 target in response to DNA damage leads to cell cycle arrest, we asked whether knocking down DAPK1 or DAPK2 might affect the cell cycle. Interestingly, knocking down DAPK2 but not DAPK1 led to a significant increase of S-phase cells upon irradiation. Moreover, knocking down DAPK2 attenuated the induction of DAPK1 upon irradiation indicating a DAPK2-DAPK1 cascade in DNA damage responses. Next, given the significant role of p21WAF1/CIP1 and p53 in DNA damage responses, we tested if DAPK2 might directly participate in a novel signaling pathway by interacting with these proteins. Indeed, pull down assays revealed that p21WAF1/CIP1 and p53 are novel DAPK2 interacting proteins. Clearly, further experiments are needed to define the DAPK2-DAPK1-p53- p21WAF1/CIP1 network in DNA repair pathways. In conclusion, we identified a novel role for DAPK1 and DAPK2 in DNA damage responses of B-ALL cells and propose a novel DAPK2/DAPK1/p53/ p21WAF1/CIP1 DNA damage regulatory pathway.

Disclosures:
No relevant conflicts of interest to declare.
Treatment of AML Relapse After Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) Using Low-Dose Azacitidine (AZA).
Authors: Chiattone Alexandre , Saliba Rima M , Andersson Borje S. , Giralt Sergio , Sharma Manish R , Rondon Gabriela , Kebriaei Partow , Hosing Chitra , Popat Uday , Parmar Simrit , Alatrash Gheath , Bashir Qaiser , Chen Julianne J , Yuen Carrie Hai-Lai , Chiattone Viviane C. , Champlin Richard E. , De Lima Marcos 
Published: October 2019

Abstract
Abstract 3445

Background:
Relapsing AML/MDS after HSCT has a dismal prognosis, with few patients achieving long-term control of the malignancy. AZA is a hypomethylating agent that is moderately active against AML/MDS, and may have beneficial immunomodulatory effects after HSCT. We have shown that a significant minority of patients with recurrent disease respond to this drug. Here, we present long-term follow-up after salvage treatment regimens that included AZA, to treat AML/MDS that recurred after HSCT.

Patients and Methods:
Twenty-three patients received low-dose AZA for recurrence. Decision to use AZA was based on clinical assessment of slow progression of disease and relatively slower disease ‘tempo' and relatively small AML bulk. AZA cohort preparative regimens for 1st HSCT were myeloablative in 12 cases, and of reduced intensity in 11 cases. AZA was used prior to or without a 2nd HSCT (n=17), or after a 2nd HSCT (n=6). Outcomes were compared to controls (n=18) that relapsed ≥ 8 months after HSCT, and did not receive AZA (8 months representing the median disease free survival (DFS) for AZA-treated patients). The control group included all patients that relapsed ≥ 8 months after allogeneic HSCT using myeloablative busulfan 130 mg/m2 and fludarabine 40 mg/m2 for 4 days. AZA was studied as a time dependent variable. AZA and controls had similar baseline characteristics as described in the Table, although median DFS after the first HSCT was 8 (range: 2–51) and 17 (range: 7–59) months, favoring the control group (p=0.08). AZA was administered outpatient, with good tolerance. Fatigue and nausea were commonly observed toxicities. Doses were 8 mg/m2 (n=1), 16 mg/m2 (n=3), 24 mg/m2 (n=10), 32 mg/m2 (n=5), 40 mg/m2 (n=2), and 75 mg/m2 (n=2), administered subcutaneously for 5 days, in 28–32-day cycles.

Results:
Median number of cycles was 4 (range, 1–44). With a median follow-up of 18 months for AZA and control patients, median survival after relapse was 17 versus 6 months, respectively for AZA and control patients. 11 (48%) AZA patients are alive, while 2 (11%) control patients are alive. Two-year overall survival (OS) for AZA and control groups was 40% and 10%, respectively. AZA and controls had similar baseline characteristics as described in the Table.

Conclusion:
Low-dose AZA was a well tolerated outpatient treatment that may improve survival after AML/MDS recurrence in selected cases. Major determinants of survival in this setting, however, were remission duration after HSCT, and use of a 2nd HSCT.

Disclosures:
No relevant conflicts of interest to declare.
Transplantation for Immunoglobulin Light Chain Amyloidosis. A Statistical Analysis of Factors Predicitng Outcome In Over 400 Patients
Authors: Gertz Morie Abraham A. , Lacy Martha , Dispenzieri Angela , Kumar Shaji , Buadi Francis , Dingli David , Ansell Stephen M. , Gastineau Dennis , Inwards David James , Johnston Patrick B , Litzow Mark R. , Micallef Ivana , Porrata Luis , Leung Nelson , Wolf Robert , Hogan William J , Hayman Suzanne R. 
Published: October 2019

Abstract
Abstract 3557

Introduction:
Autologous stem cell transplantation for patients with amyloidosis results in high reported hematologic and organ response rates compared with conventional chemotherapy.

Patients:
Four-hundred and thirty-four patients have undergone transplantation between March 8, 1996, and April 13, 2010 Table 1. Clinical parameters seen in patients with amyloid are given in Table 2. The overall day-100 mortality seen in this group of patients is 44 of 434 patients (10%).

Results:
The most important determinant of outcome is stage defined by BNP and troponin levels. Figure 1 demonstrates the survival for patients for all 3 cardiac stages. Troponin <.035; NT-proBNP <332. Stage 1 both low, Stage 3 both elevated. The survival of all patients based on whether they achieved a complete response, a partial response (>50%), or no response was analyzed. Median survival has not been reached for the complete response group, is 107 months for the partial response group, and is 32 months for the no response group (p<0.0001). Figure 2, divides the patients at the median dFLC level of 13.5 mg/dL demonstrating that for patients with a higher level of free light chain, the median survival is 87.6 months and has not been reached for those with a lower level of free light chain. A proportional hazards model for variables that impact on survival was done in all patients, and the only relevant predictor of outcome was stage (p<0.0001). When the same analysis was performed using a landmark of 6 months, the only predictor of outcome was stage (p=0.0005). When best response was incorporated into the landmark model, it was the strongest predictor of survival. The amyloid stage predicted survival (p= 0.0005), and the best response to therapy (p <0.0001). When the same analysis was performed in the entire group of 434, stage and best response each remained significant (p<0.0001).

Discussion:
There is a high response rate associated with high-dose therapy that was not observed in the melphalan and prednisone era. For eligible patients who can be transplanted safely, high-dose melphalan is an effective therapy for many patients with amyloidosis. Best response and stage at diagnosis are the best predictors of overall survival.

Disclosures:
Lacy: Celgene: Research Funding. Dispenzieri:Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Kumar:Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding.
Reapplication of High-Dose Chemotherapy with Melphalan Followed by Autologous Hematopoietic Stem Cell Transplantation as Salvage Therapy for Patients with Relapsed Multiple Myeloma
Authors: Sellner Leopold , Teodorov Sonja , Heiss Christiane , Benner Axel , Egerer Gerlinde , Dreger Peter , Ho Anthony D. , Goldschmidt Hartmut , Neben Kai 
Published: October 2019

Abstract
Abstract 3568

Introduction:
High dose chemotherapy with melphalan followed by autologous peripheral blood stem cell transplantation (PBSCT) is a standard treatment regimen for young patients with multiple myeloma. However, there are few studies, mainly with low patient counts, testing the benefit of the reapplication of high dose chemo therapy in relapsed or refractory myeloma.

Methods:
Here we retrospectively analyzed 178 patients (56% male, 44% female, median age 60 years) with relapsed or refractory myeloma who were treated by reapplying high dose chemotherapy with melphalan followed by autologous PBSCT in our institution over the last 18 years. The median follow up of this study was 54 months.

Result:
Median progression free survival (PFS) and overall survival (OS) after relapse autologous transplantation were 16 and 35 months, respectively. 66% of the patients received newer antimyeloma agents for reinduction therapy (39% thalidomide, 6% bortezomib, 21% lenalidomide). In univariate analysis, time between first transplantation and progression of disease had a significant impact on PFS and OS (p=0.001 and p<0.001). Estimated hazard ratio (HR) for prolongation of time to progression (TTP) after first transplantation of one year for PFS and OS are 0.85 and 0.73, respectively. The effect of TTP after first PBSCT on PFS and OS with respect to different clinically relevant cutoff values is illustrated in Table 1.

Conclusion:
Reapplication of high dose chemotherapy can be an effective treatment option for relapsed or refractory myeloma, in particular in patients with a time to progression after first autologous transplantation of more than one year.

Disclosures:
No relevant conflicts of interest to declare.