bluuebunny/crossref_metadata_2025_split huggingface dataset:
Case Report: A Patient with Haemorrhagic Bleeding, an Acquired Factor VIII Inhibitor and Massive Pulmonary Embolism.
Authors: Hildebrandt Martin , Richter Stephan , Schuler Markus , Ludwig Wolf-Dieter 
Published: April 2020

Abstract
A female, 48-year old patient was referred to an emergency ward with dyspnoea, haemoptysis and suspected respiratory infection that had been refractory to prior antimicrobial therapy. The onset of dyspnoea dated back to a febrile episode three months prior to presentation. The patient continued to work in spite of severe shortness of breath. Her history revealed a cervical cancer which had been treated by neoadjuvant radiochemotherapy and extended hysterectomy in 2005. Upon admission, extensive spontaneous haematomas were noted on the upper extremities. Following a diagnostic puncture of the radial artery, severe haemorrhage and compartmentalization developed, and the patient was transferred to our hospital for a surgical emergency intervention and haemostaseological counselling. A decreased factor VIII activity was noted, with a prolonged partial thromboplastin time, a normal von Willebrand Factor activity and concentration, a prolonged bleeding time and a low-titer inhibitor to factor VIII. Additionally, a profound hyponatremia (117 mmol/l) awaited explanation. Haemorrhage was treated with recombinant Factor VIIa, allowing for a successful surgical de-compartmentalization. With regard to the consistent feature of dyspnoea and partial respiratory insufficiency, bronchoscopic examination revealed only minor hemorrhagic suffusion of the bronchial epithelium, but no sign of infection or major pulmonary bleeding. Chest X-ray and laboratory findings showed right ventricular enlargement, bilateral infiltrates and an excessively high NT-pro-BNP concentration in plasma (13027 ng/l). Chest X-ray radiographs performed two months previously for suspected respiratory infection showed pulmonary infiltrates of comparable size, albeit no right ventricular enlargement. Computerized tomography of the chest showed a complete obstruction of the right pulmonary artery and of the lower branch of the left pulmonary artery. Pulmonary arterial pressure was measured at 70 mm Hg. Immunosuppressive therapy was initiated, with concomitant aPTT-adjusted anticoagulation. Upon clinical deterioration with right-ventricular failure, a catheter-based disruption of the emboli was attempted, albeit with no success. A cardio-surgical intervention with thrombendectomy was performed successfully; however, the patient succumbed to sepsis and multiorgan failure ten days later. The autopsy revealed multiple thrombi, a bilateral pulmonary haemorrhagic infarction and a disseminated lymphangiosis and hemangiosis carcinomatosa of the lungs. We conclude that the acquired inhibitor to factor VIII was of paraneoplastic origin and, although detected at a low titre, clinically relevant. Based on previous radiographic findings, a massive pulmonary embolism must be assumed to have occurred months prior to presentation. The anticoagulatory effect of the acquired inhibitor to Factor VIII may have averted the timely detection of the pulmonary embolism.
Amyloidosis Presenting with Platelet Dysfunction and Recurrent Retroperitoneal Hemorrhage (RH).
Authors: Rezazadeh Arash , Laber Damian A. , Sharma Vivek R. , Kloecker Goetz H. 
Published: April 2020

Abstract
CASE REPORT: A 59-year-old white female with history of easy bruising for 2 years and 2 episode of RH in the last 6 month admitted to ICU with her 3rd episode of RH. Her previous w/o included a BM Bx which had shown clonal population of plasma cells kappa chain restrictive (7%) with repeatedly negative SPEP and UPEP. PFA-100 was consistent with severe platelet dysfunction. During the ICU admission platelet transfusion with multiple single donor units did not correct her PFA-100 results, which were confirmed with platelet aggregation results. Both, collagen/epinephrine and collagen/ADP closure times were prolonged (&gt;300 and 128 seconds respectively). The patient however did not receive any medications to explain this apparently intrinsic dysfunction. Coagulation studies including PT, aPTT and factor II, VII, VIII, IX all were within normal limit. Factor X levels were slightly decreased (45%). Patient had selective embolization of the fourth lobar artery of the right kidney. Plasma cells in the marrow showed monoclonal expression for cytoplasmic kappa light chains by both IHC and in situ hybridization. Amorphous pink material was present in the walls of blood vessels. Plasma cells stained positively with CD138. The amyloid material stained positively with Congo red and demonstrated apple green birefringence under polarized light. Skeletal survey demonstrated multiple lytic lesions. Serum free light chain measurement showed high levels of M protein (κ) with κ to λ ration of 4.30. Patient was started on treatment with pulse dose steroid and bortezomib.
DISCUSSION: Amyloidosis can cause hemorrhage with multiple mechanisms including amyloid deposition (amyloid angiopathy), platelet dysfunction, coagulation factor deficiencies, abnormal fibrin polymerization and hyperfibrinolysis. Consumption of factor X by amyloid is often called a culprit for hemorrhage in amyloidosis. The slightly decreased level of factor X in this case provided a valuable clue for diagnosis, but was not likely a cause of bleeding in this patient. Amyloid induced platelet dysfunction along with amyloid angiopathy lead to life threatening hemorrhage in our patient. The mechanism of this platelet dysfunction, which also affected the transfused platelets, is not well explained. This effect on platelets complicates the clinical management. The case also illustrates the value of the free light chain assay, which is more sensitive than SPEP and UPEP. These commonly used tests to diagnose plasma cell dyscrasias are reportedly false negative in 3% of cases.
CONCLUSION: Plasma cell dyscrasia has a wide variety of presentation and should be considered as a part of bleeding work up in complex cases.
Phase II Trial of Oral Panobinostat (LBH589) in Patients with Refractory Cutaneous T-Cell Lymphoma (CTCL).
Authors: Duvic Madeleine , Becker Jürgen C. , Dalle Stephane , Vanaclocha Francisco , Bernengo Maria Grazia , Lebbé Celeste , Dummer Reinhard , Hirawat Samit , Zhang Lei , Marshood Miriam , Laird Glen , Prince H. Miles 
Published: April 2020

Abstract
Background: Panobinostat is a histone deacetylase inhibitor that has shown promising results in cutaneous T-cell lymphoma (CTCL).
Objectives: An open-label, multicenter, Phase II study is being conducted with a primary objective of establishing the efficacy and safety of the pan-deacetylase inhibitor, panobinostat (LBH589), for patients (pts) with relapsed/refractory CTCL with Stage IB–IVA mycosis fungoides (MF) or Sézary syndrome (SS).
Methods: Inclusion criteria include adequate organ function, no clinically significant cardiovascular abnormalities (QTcF ≤ 450 ms, ECOG PS ≤2), failure of ≥2 prior systemic therapies, and no prior HDAC inhibitor treatment. Pts were grouped as having bexarotene therapy (Group [Gr] 1) or bexarotene naïve (Gr 2). Panobinostat was administered at a dose of 20 mg orally on Days 1, 3, 5, weekly, every 28 days until progression or unacceptable toxicity. Response was based on a composite score, including skin assessment with the modified Severity-Weighted Assessment Tool (mSWAT) and systemic disease assessed by CT scan.
Results: To date, 95 pts (Gr 1=62; Gr 2=33) have enrolled with median age of 58 yrs [range 25–88]: 58 male, 37 female; 70 MF, 25 SS. Median prior treatment regimens are 4 and 3 for Gr 1 and 2, respectively. Most pts were ≥Stage IIB at study entry (Gr 1=42; Gr 2=26) and received 1–17+ (median=3) treatment cycles of panobinostat. In Gr 1, 11/62 pts have had confirmed skin responses by SWAT, including 2 complete skin responses. Confirmatory CT scans are pending for 2 patients. In Gr 2, 4/33 pts had confirmed skin and CT scan responses. Common AEs (&gt;20%; all grades, regardless of causality) included diarrhea, thrombocytopenia, nausea, pruritus, fatigue, and asthenia, and Grade 3/4 AEs (&gt;2%, regardless of causality) included thrombocytopenia, neutropenia, pruritus, diarrhea, and hypophosphatemia. Of 4,542 ECGs analyzed, 2 pts have had QTcF &gt;480 ms; 4 had QTcF &gt;60 ms increase from baseline.
Conclusions: Panobinostat continues to demonstrate encouraging clinical activity with a manageable safety profile in pts with CTCL. Per predefined criteria, Group 2 enrollment to Stage 2 is open. Updated efficacy and safety data will be presented.
De-Immunization of Human Factor VIII: Identification of Epitopes in the C2 Domain
Authors: Moise Leonard , Skupsky Jonathan , Tassone Ryan , McMurry Julie A , Martin William D , De Groot Anne S. , Scott David W. 
Published: April 2020

Abstract
Most immune responses to protein antigens are dependent on T-cell recognition of discrete peptide epitopes presented in an MHC groove. The pattern of peptide recognition can be predicted from the primary structure of a given protein based on residues that bind (anchor) to a given HLA phenotype. Algorithms such as EpiMatrix can be applied to identify such epitopes and measure the potential immunogenicity of proteins based on epitope content. One approach to reduce immunogenicity is to generate recombinant proteins whose constituent epitopes have been modified so as to reduce their HLA binding. Modification of the sequence can be performed in silico using algorithms such as OptiMatrix. This “de-immunization” method has been used effectively with a number of therapeutic proteins already in use in clinical trials. It may therefore also be possible to target those residues of fVIII that, while contributing to HLA binding, can be mutated without altering the functional ability of fVIII to initiate clotting. We have begun this de-immunization process with the fVIII, starting with C2 domain because C2 has been confirmed to be a major target of both T cells and inhibitory antibodies. Using EpiMatrix, we selected 10 peptides in human fVIII that would be predicted to bind to eight class II HLA DR molecules that encompass over 95% of the U.S. population. These epitopes were synthesized and eight of the ten were assayed in vitro and found to bind to HLA at IC50 &lt;100μM. Immunization of fVIII knockout mice with whole fVIII or with constituent fVIII peptide epitopes resulted in significant T cell proliferation to the peptide epitopes as measured by thymidine incorporation assays. By contrast, homologous peptide epitopes modified by 1–2 residues elicited significantly lower levels of proliferation. These preliminary results point to the feasibility of generating a de-immunized fVIII molecule with reduced immunogenicity; validation of these results is planned. If such proteins retain even partial activity to initiate clotting, then they would become useful in treating hemophilia A patients to avoid inhibitor formation. (Supported by NIH R43 HL088834-01)
Dual Effect of Platelet Factor Four on the Activities of Factor Xa
Authors: Fiore Martine Marie , Mackie Ian J 
Published: April 2020

Abstract
Platelet Factor 4 (PF4) is a cationic molecule that binds to heparin with high affinity and neutralises the activity of the latter. Our recent studies indicate that heparin can promote an interaction of fXa with PF4 since neutralization of heparin activity by PF4 was dependent on the concentration of protease. To examine the contribution of PF4 in protease function, fXa activity was determined in chromogenic assays. Upon preincubation with fXa and heparin, PF4 (at a concentration of 100 nM) decreased the kcat of S2765 peptide hydrolysis 4-fold and that of prothrombin activation about 2-fold. These results suggested an effect of PF4 on the primary specificity of the protease. In fact, PF4 exerted a mild effect (30 % decrease) on the Na+ dependence of fXa, consistent with linkage between Na+ and S1. PF4 preincubation with fXa also prevented the binding of the S1 probe p-aminobenzamidine (pAB) while simultaneous addition of PF4 and pAB diminished the contribution of PF4. In the presence of excess fVa (relative to fXa), kinetic parameters measuring fXa amidolytic activity in the presence of PF4 were restored to control values in the absence of PF4. Interestingly, high concentrations of PF4 (&gt; 1 μM) totally restored fXa activity toward peptidyl substrate and strongly enhanced prothrombin activation, indicating a dual effect of PF4 on fXa activities. The inhibitory contribution of PF4 during prothrombin activation was due to a three-fold decreased affinity of fXa for fVa while enhancement of prothrombin activation was accompanied by a three-fold increase in fVa-dependent cofactor activity. Thus, the effects of PF4 possibly involved a region of the heparin/fVabinding exosite that is linked to the S1 and Na+ sites. These findings suggest that PF4 is a probe of fVa-dependent changes occurring in the active site of fXa and provide an explanation for the in vivo paradoxical effects of PF4 reported in the literature.
Antisense Transcripts Negatively Regulate Transcription of Multiple Variegated Killer Immunoglobulin-Like Receptor (KIR) Genes
Authors: Cichocki Frank , Lenvik Todd , Anderson Stephen K , Miller Jeffrey S. 
Published: April 2020

Abstract
Natural killer cells are CD3 negative large granular lymphocytes that lyse virally infected and malignantly transformed targets. NK cell functions are regulated by an array of inhibitory and activating receptors, including members of the killer immunoglobulin-like receptor (KIR) family. Human KIR genes are expressed in a variegated and clonally restricted manner on the surface of mature NK cells. While it is well established that individual KIR gene expression is strongly correlated with the DNA methylation status of CpG dinucleotides within the promoter region proximal to the transcriptional start site, the mechanisms that regulate variegated KIR expression are largely unknown. Our goal is to uncover the genetic mechanisms governing KIR transcriptional regulation. We have recently identified an active distal promoter element approximately 1 Kb upstream of the transcriptional start site. This region contains c-MYC binding sites, and KIR expression is increased when MYC is overexpressed in developing NK cells or when c-MYC is physiologically increased by IL-15 activation. Bi-directional promoter activity is found within the previously characterized proximal promoter of all KIR genes. Therefore, double-stranded RNA with homology to the KIR promoter can be generated within this non-coding region. The generation of double-stranded RNA has recently been shown to contribute to promoter DNA methylation of the p15 gene in mammalian cells through a Dicer-independent mechanism. Using quantitative real-time PCR, we found that purified peripheral blood CD56+/KIR3DL1− NK cells express 5-fold more KIR3DL1 antisense transcript than purified CD56+/KIR3DL1+ cells. Therefore, the transcriptional activation of the KIR3DL1 gene correlates with a significant decrease in KIR3DL1 antisense expression. To explore the possibility that KIR antisense transcripts can silence KIR expression, we over-expressed the KIR3DL1 antisense transcript in CD34+ hematopoietic precursor cells and differentiated these cells into NK cells in vitro. After 21 days in culture, we assayed KIR3DL1 mRNA levels using quantitative real-time PCR. KIR3DL1 expression was reduced 4-fold compared to eGFP control cultures, further supporting the hypothesis that antisense transcripts negatively regulate KIR expression. Importantly, expression of the KIR2DL4 gene, which does not contain a promoter with significant homology to KIR3DL1 promoter, was not affected by KIR3DL1 antisense overexpression. This provides the first evidence for gene silencing through double-stranded RNA in the immune system and may be the key mechanism for the establishment of DNA promoter methylation within the KIR locus. Understanding the mechanisms of KIR expression, a requisite for NK cell education/licensing, may allow us to understand the acquisition of effector function and manipulate it for therapeutic benefit.
Beta-catenin Is Essential for Survival of Leukemia Stem Cells Insensitive to Kinase Inhibition in Mice with BCR-ABL Induced Chronic Myeloid Leukemia.
Authors: Li Shaoguang , Hu Yiguo , Chen Yaoyu , Douglas Lori 
Published: April 2020

Abstract
Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia (CML) induced by the BCR-ABL oncogene is believed to be developed from leukemic stem cells (LSCs), and we have previously shown in mice that LSCs for CML express the same cell surface markers that are also expressed on normal hematopoietic stem cells. Although the inhibition of BCR-ABL kinase activity by imatinib is highly effective in treating human Ph+ CML in chronic phase, it is difficult to achieve molecular remission of the disease, suggesting that LSCs remain in patients. In this study, we find that following imatinib treatment, LSCs not only remained but also accumulated increasingly in bone marrow of CML mice. This insensitivity of LSCs to imatinib was not due to the lack of BCR-ABL kinase inhibition by imatinib, and proliferating leukemic cells derived from LSCs were still sensitive to growth inhibition by imatinib. These results identify a LSC survival pathway that is not inhibited by imatinib. Furthermore, we show that b-catenin in the Wnt signaling pathway is essential for survival and self-renewal of LSCs, providing a new strategy for targeting these cells.
Arrestin-2 Differentially Regulates PAR4 and P2Y12 Receptor Signaling in Platelets
Authors: Li Dongjun , Woulfe Donna 
Published: April 2020

Abstract
Arrestins play important roles in the function of G Protein-Coupled Receptors (GPCRs) in many cells, but their roles in platelets remain uncharacterized. While the classical role of arrestins is considered to be the internalization and desensitization of GPCRs, more recent studies suggest that arrestins can serve as molecular scaffolds to recruit phosphatidyl inositol-3 kinases (PI3Ks) to GPCRs and promote PI3K-dependent signaling. Due to the multifunctional role of arrestins, we sought to determine whether arrestins regulate Akt activation in platelets and thrombosis in living animals. Co-immunoprecipitation experiments indicate that arrestin-2 associates with PAR4 in thrombin-treated platelets and P2Y12 in ADP-treated platelets, but neither receptor in resting cells. Interestingly, association of arrestin-2 with PAR4 was also stimulated by ADP and PAR4-induced association of arrestin with PAR4 was inhibited by P2Y12 antagonists or apyrase. To determine the functional role of arrestin-2 in platelets, ADP- and thrombin receptor-stimulated Akt phosphorylation was compared in platelets from arrestin-2 knock-out versus WT mice. Akt phosphorylation stimulated by 0.8 mM AYPGKF PAR4 agonist peptide was reduced by an average of 77% in arrestin-2 knock-out platelets compared to WT controls (significantly different, p=0.007, n=3 in each group), but ADP-stimulated Akt phosphorylation was unaffected (p=.38, n=3 each). PAR4-stimulated fibrinogen binding was also reduced in arrestin2−/− platelets (by 58.5% in 1 mM AYPGKF-stimulated platelets compared to WT controls), whereas ADP-stimulated fibrinogen binding was not. Finally, arrestin2 knock-out mice were less sensitive to ferric chloride-induced thrombosis than WT mice: 55% of WT mice (n-=9) formed occlusive thrombi after 2min15sec exposure of the carotid artery to 10% ferric chloride, whereas only 11% of WT mice (n=9) formed occlusive thrombi under the same conditions. In conclusion, arrestin-2 associates with both PAR4 and P2Y12 receptors, but differentially regulates their signaling to Akt and fibrinogen binding and appears to play a net positive role in regulating thrombosis in vivo.
A Comprehensive Lymphocyte Analysis of Dasatinib Treated Chronic Myelogenous Leukemia Patients Reveals T-Cell Oligoclonality.
Authors: Powers John J. , Painter Jeffrey S. , Dubovsky Jason A , Epling-Burnette P.K. , Pinilla Javier 
Published: April 2020

Abstract
On the forefront of targeted cancer therapy are second generation tyrosine kinase inhibitors (TKIs) which impact the outcome of chronic, accelerated, and blast phase chronic myelogenous leukemia (CML). Among these TKIs dasatinib is particularly effective for the treatment of imatinib-resistant Philadelphia chromosome-positive CML; although this drug has been associated with the generation of pleural effusions, fevers, and colitis in some patients. Recent data links these side effects to oligoclonal expansions of large granular lymphocyte (LGL) immunophenotype. To further characterize these events we conducted a comprehensive immunophenotye, T-cell receptor variable region, KIR, and HLA analysis of seven CML patients receiving dasatinib, two of which developed adverse reactions in association with lymphocytosis. Flow cytometric analysis confirmed these proliferative events and elucidated a previously undescribed CD3-CD8+CD56+ population. In addition, we identified multiple patients with decreased CD4 to CD8 T-cell ratios and a shift in CD4+ and CD8+ lymphocyte populations towards an effector and terminal memory phenotype (CD62L-CD45RA-and CD62L-CD45RA+ respectively). Further analysis of the T-cell receptor beta chain showed that all seven patients had oligoclonal populations of either CD4 or CD8 T-cells significantly greater than that of healthy donors. Most of these findings were independent of the occurrence of adverse reactions. All in all our data implicates dasatinib in generating oligoclonal lymphocyte expansions of various phenotypes in all CML patients. It is still unclear as to the underlying molecular mechanisms inducing these expansions, but further exploration could help to prevent or alleviate these reactions and could conceivably provide new tools for future directed immunotherapy.