bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bleeding On Anti-Platelets: A Single Center Quality Assurance Project
Authors: Fountzilas Christos , Levine Randy L. 
Published: October 2019

Abstract
Abstract 4708

Background:
Treatment of CNS hemorrhage in patients on anti-platelets usually includes transfusion of platelets. Management of bleeding in other sites has not been thoroughly studied.

Objective:
To identify practice patterns of treatment of hemorrhage in patients on anti-platelets (aspirin and clopidogrel) at a tertiary care hospital within a 3 month period.

Methods:
This is a retrospective chart review. The Emergency Department provided a list of admitted patients. Target population was identified using the Emergency Department computer system. The patients chart was used in order to extract the following data: age, gender, co-mobridities, medications, baseline and lowest hemoglobin, platelet count, international normalized ratio, partial thromboplastin time and thrombin time, source and type (spontaneous vs trauma) of bleeding, use of packed red blood cells transfused within the first 24 hours, transfusion of platelets; prothrombin complex concentrate; fresh frozen plasma; factor VII; use of desmopressin, surgery or endoscopy within 48 hours from admission. Bleeding was categorized as life threatening, major or minor according to the International Society on Thrombosis and Hemostasis criteria. Statistical analysis was performed with the use of Excel (Microsoft).

Results:
31 patients with bleeding on anti-platelets were admitted from April 2012 to June 2012. Baseline characteristics and treatment practices are summarized in Table 1. The majority of the bleeds were due to aspirin alone, and anti-platelet agents were discontinued 93% of the time. Most bleeds requiring admission were classified as either life threatening or major. Frequency of packed red cell transfusion in life threatening bleeds was 5/6 (83%), 11/17 (65%) in major bleeds and 2/8 (25%) in minor bleeds. 4 patients were transfused with platelets (one had a CNS bleed), all had the anti-platelets discontinued and they had lower platelet counts compared to non transfused patients [93.2(84) vs 217(80.3), p=0.02]. No patient required desmopressin. All patients who had their anti-platelets continued had minor bleeds. All the bleedings stopped within 48 hours from admission and no deaths secondary to hemorrhagic shock were recorded.

Discussion:
This is a quality assurance project to assess current physician practices for the management of bleeding in patients on anti-platelet agents. Except for the actual platelet counts, there is no obvious difference between patients transfused with platelets vs non-transfused. At our institutions, anti-platelet related major bleeds are not routinely managed with platelet transfusions. There is a need for additional research to better clarify management. Our study is limited by the fact that it is a retrospective, single institution study. Furthermore, bleeding in inpatients on anti-platelets was not assessed.

Disclosures:
No relevant conflicts of interest to declare.
Comparative Study of the Biological Characteristics of Serum-Free and Fetal Bovine Serum-Contained Medium Cultured Umbilical Cord-Derived Mesenchymal Stem Cells
Authors: Chen Guanghua , Yang Ting , Qiao Man , Liu Huiwen , Depei Wu 
Published: October 2019

Abstract
Abstract 4737

Objective:
To compare the difference of biological characteristics between human umbilical cord-derived mesenchymal stem cells (UC-MSC) cultured by serum free medium and fetal bovine serum-contained complete medium and to create a xenogeneic protein-free UC-MSC culture system.

Methods:
Healthy human umbilical cord segments were digested with collagenase. Umbilical cord-derived mesenchymal stem cells were cultured by serum free MesenCult-XF medium and FBS-based αMEM complete medium. We analysed the morphology, immunophenotype, expansion potential, trilineage differentiation potential, karyotype and immunosuppression of early passage of UC-MSC.

Results:
The average cell diameters of UC-MSC in suspension cultured by serum free medium and FBS-based medium are 26 (18–39) μm and 35 (20–61) μm, respectively. Cell expansion folds with serum free medium and FBS-based medium were (5.2±0.2) and (3.5±0.1) in the first five passage, respectively. The expansion potential of MSCs was significantly higher with serum free medium compared to FBS-based medium (P<0.05). A panel of markers as CD29, CD44, CD90, CD73, CD105 and HLA-ABC were expressed by human UC-MSC. Hematopoietic lineage markers CD34, CD45 and HLA-DR were not detectable on UC-MSC. The cpm were (4.57±0.14)×104, (2.04±0.16)×104 and(0.42±0.04)×104 when serum free medium cultured MSCs were added to the cultures at ratios MSCs/T cell of 1:100, 1:10 and 1:5. While the cpm were (4.57±0.14)×104, (2.04±0.16)×104 and(0.42±0.04)×104when serum free medium cultured UC-MSCs were added to the cultures. The immunosuppressive potential of serum free medium-cultured UC-MSC was higher than that of serum-contained medium cultured UC-MSC at three different ratios MSC/T cell (P<0.05). Conclusion Compare with serum-contained medium cultured early passage of UC-MSC, the cell diameter of serum free medium cultured MSCs was smaller and the expansion potential was higher. No xenogeneic proteins were presented in UC-MSC preparation when UC-MSC was cultured with serum free medium. Human UC-MSC suppresses T-cell proliferation in a dose-dependent manner. The immunosuppressive potential of UC-MSC was higher when cultured in serum free medium compared with FBS-based medium.

Disclosures:
No relevant conflicts of interest to declare.
Hemoglobin Agenogi in Argentina: Case Report
Authors: Martin Ana Paula , Gargallo Patricia Martha , Bragos Irma Margarita , Abbate Alejandro , Ojeda Mara Jorgelina , Montero Verónica Susana 
Published: October 2019

Abstract
Abstract 4776
Hb Agenogi [b90(F6)Glu–>Lys], a beta chain variant was detected in a 44-years-old female patient of italian ancestry. She showed a hypochromic microcytic anemia and was treated as ferropenic anemia since she was 27 years old. The complete cell blood count revealed the following results: RBC: 4.01× 1012/L, PCV:30.9%, Hb:10.4 g/dl, MCV: 77fl, RDW 13.5%, MCH: 25.9 pg, MCHC:33.7%; reticulocytes: 0.6% and the peripheral blood smear showed no basophilic stippling. Serum vitamin B12, folate, iron, transferrin, transferrin saturation and ferritin were normal. The electrophoresis performed on agarose (alkaline pH) revealed a band of 44.5% with a mobility between Hb C and S. The unstable hemoglobin test was positive and the P50 was 31.3 mmHg (NR: 24 –28 mm Hg). This slow-moving hemoglobin, mild unstable and with decreased oxygen affinity was further characterized by sequencing of the amplified DNA, showing the substitution of glutamic acid (GAG) to lysine (AAG) at position 90 of the β globin chain This mutation has been described in only nine families, this is the second affected case in Argentina.

Disclosures:
No relevant conflicts of interest to declare.
The Feature of MALT1-A20-NF-κB Expression Pattern Provide Important Insights Into the Therapeutic Benefit for T-ALL
Authors: Ma Yu , Wu Xiuli , Wang Xu , Zhang Fan , Yang Lijian , Chen Shaohua , Li Bo , Li Yangqiu 
Published: October 2019

Abstract
Abstract 4810
The knowledge of oncogenic signaling pathways of T-cell acute lymphoblastic leukemia (T-ALL) is still limited. Constitutive aberrant activation of NF-κB signaling has been detected in various lymphoid malignancies and plays a key role in the development of these malignancies. The zinc finger-containing protein A20 (also known as Tumor Necrosis Factor Alpha-Induced Protein 3 or TNFAIP3) is a central regulator of multiple NF-κB activating signaling cascades. A20 is inactivated and results in constitutive NF-κB activation in tumor cells. A20 is now known to act as a crucial tumor suppressor in various hematological malignancies like lymphomas. MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1) plays a critical role in the regulation of NF-κB pathways, and mediated rapid proteolytic cleavage and inactivation of A20. To further characterize the function of these signal molecules, we analyzed the expression levels of A20, NF-κB and MALT1 genes in peripheral blood mononuclear cells (PBMCs) of 19 patients newly diagnosed with T-ALL (aged 4–70 years, median 25), and investigated the relationship between the aberrant expressions of these genes and T-ALL. Twenty-nine healthy individuals (aged 20–57, median 28) served as controls. We found that the expression levels of A20 in T-ALL patients (6.057±5.275) were significantly lower than healthy group (9.865±5.370) (P=0.020), while the expression levels of NF-κB (0.560±0.425) and MALT1 (2.712±3.127) in T-ALL patients were significantly higher than healthy group (0.337±0.311, 0.713±0.464) (P=0.041, P=0.001). The expression levels of A20 had a significant negative correlation with the expression of MALT1 (r=−0.628, P=0.009), and the reduced levels of A20 had a positive correlation with the increased expression of NF-κB in T-ALL (r=0.588, P=0.017). In conclusion, the overexpression of MALT1 in T-ALL causes constitutively cleavage and inactivation of A20 to enhance NF-κB signaling, and may contribute to the pathogenesis of T-ALL. Thus, MALT1 may consider as a potentially attractive target for the development of T-ALL therapeutics.

Disclosures:
Ma: National Natural Science Foundation of China (No. 91129720): Research Funding. Wu:National Natural Science Foundation of China (No. 91129720): Research Funding. Wang:National Natural Science Foundation of China (No. 91129720): Research Funding. Zhang:National Natural Science Foundation of China (No. 91129720): Research Funding. Yang:National Natural Science Foundation of China (No. 91129720): Research Funding. Chen:National Natural Science Foundation of China (No. 91129720): Research Funding. Li:National Natural Science Foundation of China (No. 91129720): Research Funding. Li:National Natural Science Foundation of China (No. 91129720): Research Funding.
Pediatric Mixed Phenotype Acute Leukemia-41 Cases Report
Authors: Gao Huifang , Liu Yi , Zhang Ruidong , Xie Jing , Shi Huiwen , Wu Minyuan , Huang Pengli , Zheng Huyong 
Published: October 2019

Abstract
Abstract 4811

Background:
Mixed phenotype acute leukemia (MPAL) is a rare type of acute leukemia with a poor clinical outcome, defined by the blasts express antigens of more than one lineage. MPAL was also named as mixed lineage leukemia, bilineal leukemia, biphenotype leukemia historically. The properly diagnosis of MPAL is crucial for the treatment. The scoring system proposed by European Group for Immunological Characterization of Leukemia (EGIL) in 1995 was the first standard criteria to diagnose MPAL. In 2008, WHO proposed a new scoring criteria to define MPAL. But both of these two systems have their limitation.

Methods:
We retrospectively analyzed 41 pediatric patients with mixed phenotype acute leukemia from 2000 to 2010 according to EGIL scoring system. All the 41 patients were reclassified according the 2008 WHO classification. Diagnosis, cytogenetics, immunophenotype, treatment and prognosis were analyzed.

Results:
There were 25 male and 16 female with the mean age of 8 years old. According to EGIL scoring system, the phenotype included T/myeloid (n=16), B/myeloid (n=13), T/B(n=11) and T/B/AML(n=1), respectively. Among the patients, there were 4 MPAL with t(9;22)(q34;q11), 5 with t(12;21)(p13;q22), 1 with inv(16)(p13;q22) and 1 with t(9;9). The overall complete remission (CR) rate was 47% treated by ALL regimen (n=19) and 17% by the AML+ALL combined therapy (n=6). MPAL with t(9;22)(q34;q11) showed poor response (4/4). MPAL with t(12;21)(p13;q22) had a good response to the treatment(4/5). Based on the 2008 WHO criteria, 24 of the 41 MPAL patients were reclassified as MPAL, including T/myeloid type(n=11), B/myeloid type(n=6), T/B(n=7). Three MPAL patients with t(12;21)(p13;q22) diagnosed by EGIL system were excluded by 2008 WHO criteria.

Conclusion:
Our results suggest that MPAL is a poor outcome disease requiring more accurate classification based on genetic and gene classification. MPAL with t(9;22)(q34;q11) is a predictor of poor outcome. MPAL with t(12;21)(p13;q22) could be treated only by ALL regimen. MPAL with both lymphoid and myeloid markers appears to achieve a better CR rate if treated by ALL regimens alone than treated by ALL+AML combined regimens. Further studies are needed to determine a standard diagnosis and treatment approach for MAPL.

Disclosures:
Zheng: Beijing Health System High-level Technical Personel Plan: Research Funding.
Clinical Course and Pathological Findings in a Series of Patients with Aggressive Natural Killer (NK) Cell Leukemia
Authors: Liebman Mira F , Sheridan Brian L. 
Published: October 2019

Abstract
Abstract 4823

Background:
NK cell leukemia is a rare, malignant proliferation of NK cells associated with Epstein Barr Virus (EBV). The World Health Organization (WHO) defines NK cell leukemia based on a blood film showing pancytopenia, and circulating leukemic cells, which are positive for CD2, cytoplasmic CD3, CD56, and cytotoxic molecules. The neoplastic cells may have a wide range of appearances, including cells that resemble large granular lymphocytes, highly atypical cells with abundant cytoplasm, and azurophilic granules. Reported cytogenetic abnormalities have included 6q deletion, 11 q deletion and losses of 7p and 17p.
Previous publications in the medical literature have been limited to case reports, mostly from Asian centers.

Methods:
We conducted a retrospective chart review of all aggressive NK cell leukemia diagnoses at an academic medical center, from 2008–2012.

Results:
We identified 4 cases of aggressive NK cell leukemia. The median age at diagnosis was 57 years. 3 out of 4 cases were male, and 3 of 4 were associated with EBV infection. All patients presented clinically with cytopenias, one patient had an elevated white blood cell count, 31 × 10 9per liter with the others presenting with pancytopenia. All had constitutional symptoms (including fever and night sweats) at diagnosis. 2/4 cases had extramedullary involvement, including splenomegaly and lymphadenopathy. One patient presented with hemophagocytic lymphohistiocytosis. 2/4 patients had CNS involvement. All had a large proportion of circulating neoplastic cells (12–80%).
The blood film examination in all cases demonstrated large, pleomorphic neoplastic cells. Most (3/4) had distinct nucleoli and 1/4 had large azurophilic granules in the cytoplasm. The immunohistochemistry profile showed positivity for cytoplasmic CD3, CD56 and CD7 in all cases. 3/4 cases were positive for CD11c. 2/4 patients had unique complex karyotypes including chromosome 3p duplication, deletion of 16q, addition 1p, trisomy 7, trisomy 8, isochrome 17q and near tetraploid karyotype.
All patients received treatment with various chemotherapeutic protocols; however none received radiation therapy, or stem cell transplantation. 2/4 cases achieved a short remission. All patients had poor clinical outcomes with median survival of 12 months (range 2–19 months), which is consistent with prior reports.

Conclusion:
This case series serves to confirm the typical clinical presentation, and poor prognostic outlook, of patients with aggressive NK cell leukemia. This rare malignancy was previously described only in individual case reports. In our patient population, we noted complex, novel cytogenetic findings. Our study reaffirms the need for new therapeutic modalities to improve the poor prognosis for this disease.

Disclosures:
No relevant conflicts of interest to declare.
Viral Ortholog Complements Mir-155 Deficiency-Associated Abnormalities and Together with Additional Viral Mirnas Causes B Cell Hyperplasia and B Cell Lymphoma
Authors: SIN Sang-Hoon , Dittmer Dirk P 
Published: October 2019

Abstract
Abstract 4866
MicroRNA-155 (miR-155) is overexpressed in many types of cancers including B cell lymphomas. It has also an essential function in GC development. These functions are conserved among species and miR-155 knockout (ko) mice are deficient in GC development in Peyer's patches (PP) and lymph nodes. The human tumor virus Kaposi sarcoma associated herpesvirus (KSHV) encodes an ortholog to miR-155, named miR-K12-11. MiR-155 and miR-K12-11 share 100% seed sequence homology (Nature. 2007 Dec 13;450(7172):1096-9, J Virol. 2007 Dec;81(23):12836-45). Another human herpesvirus, Epstein-Barr Virus, induces mir-155 upon infection and immortalization of naïve B cells in culture. To test the hypothesis that miR-K12-11 can complement the normal function of miR-155 in vivo, we generated transgenic mice, which express miR-K12-11, as well as the other 21 KSHV miRNAs. Using this mouse model, we show that KSHV latency locus which contains a viral ortholog of miR-155, KSHV miR-K12-11 complements B cell abnormalities associated with the lack of miR-155. Germinal center (GC) formation is rescued in spleen and PP and lowered immunoglobulin level is also augmented to normal in KSHV latency locus transgenic mice with miR-155 ko background. Furthermore, mature B cells were chronically activated, leading to hyperglobulinemia triggered by increased plasma cell frequency. Marginal zone (MZ) B cells developed hyperplasia and the mice had an augmented response to T-dependent antigen as well as the TLR4 ligand LPS in vivo. This suggests that by mimicking miR-155 (and other functions) this human tumor virus drives the expansion of infected B cells, which if left unchecked can accumulate secondary mutations leading to post-GC lymphoma and multicentric Castleman's disease.

Disclosures:
No relevant conflicts of interest to declare.
Relative Stability Of Plasma Cells Immunophenotype In Multiple Myeloma Over Time
Authors: Tessoulin Benoit , Legouill Steven , Eveillard Marion , Robillard Nelly , Wuilleme Soraya , Gastinne Thomas , Touzeau Cyrille , Pellat-Deceunynck Catherine , Bene Marie C , Moreau Philippe 
Published: October 2019

Abstract

Emerging evidence indicates that multiple myeloma (MM) can follow a number of evolutionary pathways over a patient’s disease course. Recently, genomic data have shown the coexistence in many patients of several tumour types, which could be either genetically stable, evolving linearly or be constituted of heterogeneous clonal mixtures with predominant clones shifting over time (Keats, Blood 2012;120:1067-1076). Little is known however of immunophenotypic evolution of the myeloma cells (MM cells) during MM progression.
In a retrospective single-centre analysis of tumoral immunophenotypes, we examined sequential bone marrow or peripheral blood samples from 51 MM patients. Multiparameter flow cytometry was performed to assess MM phenotype using CD38 and CD138 expression as well as intracytoplasmic light chain usage restriction in most cases. The presence or absence of CD19, CD20, CD27, CD28, CD56 or CD117 on the MM cells’surface was investigated additionally. A median of 4 of the latter antigens was examined per sample. Most MM cells were homogeneous in the expression or absence of expression of the differentiation antigens investigated. Immunophenotype changes were defined as the loss or gain of at least 1 antigen. Whenever partial expression of one or several antigens was observed on MM cells, indicating MM subsets, the presence of subclones was suspected.
Samples were obtained at diagnosis and relapse for 33 MM patients, and during consecutive relapses for 18. The total amount of analysed samples was 109, with a median of 2 samples per patient (range: 2-3). A modification of immunophenotype occurred in 22 patients (43%), with one antigen change (68%), two antigens changes (18%) or three antigens changes (14%). Immunophenotypic changes are summarized in table 1. For 20% of the cases or more, this involved CD28 (n=11, balanced gain or loss) or CD27 (n=7, mostly loss). CD56 expression, scarcely negative on the first assessment, was gained at relapse in three cases. Other antigens were expressed in a stable fashion over time. Eighteen (35%) of the patients had at least a subclone on the first immunophenotype, which was lost and/or modified in 14 / 18 patients at time of subsequent relapse.
There was no significant impact of immunophenotypic modifications on overall survival rates Similarly, the presence of a subclone at first examination, or the immunophenotypic change of this subclone over time was not associated with differences in overall survival rates.
In conclusion, this retrospective single centre study demonstrates that the immunophenotype of MM cells is mostly stable during the course of the disease. When changes occur, they do not seem to affect the clinical course of the patients. These preliminary results need confirmation on a larger and prospective trial.

Disclosures:
No relevant conflicts of interest to declare.
Identification Of a Novel Small Molecule Inhibitor Of ASK1 As a Potent Anti-Platelet Agent
Authors: Ulhas Naik Meghna , David Maloney , Turaga Ramya , Ichijo Hidinori , Naik Ulhas P 
Published: October 2019

Abstract
Apoptosis signal-regulating kinase (ASK1) is a serine/threonine kinase, belonging to the MAP kinase-kinase-kinase family, which is activated in response to stress. However, its presence and role in platelets are not known. We found that ASK1 is expressed in platelets and is rapidly activated during platelet stimulation by various agonists in a dose-dependent manner. In addition, we found that TRAF2/6, known endogenous activators of ASK1, are expressed in platelets and associate with ASK1 upon platelet activation with agonists. Furthermore, genetic ablation of Ask1 significantly delayed tail-bleeding time (P=0.2x10-9). While WT mice showed an average bleeding time of 100 s, the Ask1 null mice had an average bleeding time of 576 s. A carotid artery injury induced by 10% FeCl3 showed a significantly increased (P=0.0003) time of occlusion and unstable thrombus formation in Ask1 null mice. Furthermore, we found that loss of Ask1 renders significant protection to the mice from pulmonary thromboembolism induced by a mixture of collagen and epinephrine as determined by increased survival and lack of large occlusive thrombi in the lung. We also found that ADP- and AYPGKF (PAR4 receptor peptide) -induced platelet aggregation was diminished in Ask1 null mice compared to WT mice. Furthermore, PAR4 peptide-induced alpha- and dense-granular secretion was also reduced in Ask1 null platelets compared to WT. Interestingly, we also found that Ask1 null platelets bind less FITC-fibrinogen compared to the WT upon activation by PAR4 peptide. Furthermore, thrombin failed to activate MKK6 and p38 in Ask1 knockout platelets, showing that Ask1 is indispensable for p38 activation by thrombin. These results indicated that ASK1 regulates platelet function by augmenting platelet secretion as well as fibrinogen receptor activation, making it an important target for combating thrombosis. We therefore synthesized a novel and highly specific ASK1 inhibitor, N-(6-(1H-imidazol-1-yl)imidazo[1,2-a]pyridin-2-yl)-4-(tert-butyl)benzamide (IPTB) based on the published report. IPTB has been found to be a very potent inhibitor that inhibits ASK1 activity at nM concentrations. IPTB is also highly specific to ASK1 and does not affect activities of related protein kinases such as ASK2, MEKK1, TAK1, and ERK1. We found that in human platelets, IPTB dose-dependently inhibits p38 activation induced by a variety of platelet agonists. Furthermore, IPTB dose-dependently inhibited ADP and PAR4 peptide-induced platelet aggregation. Interestingly, IPTB also dose-dependently inhibited platelet spreading on immobilized fibrinogen. Our results strongly suggest that the dose of IPTB could be adjusted so that it attenuates thrombosis without affecting hemostasis. This development would make IPTB a novel potential therapeutic agent to be used to combat thrombotic disorders.

Disclosures:
No relevant conflicts of interest to declare.