bluuebunny/crossref_metadata_2025_split huggingface dataset:
Junctional Adhesion Molecule a Helps Maintain Integrin αIIbβ3 in Resting State
Authors: Naik Meghna Ulhas , Stalker Timothy J. , Brass Lawrence F. , Naik Ulhas Pandurang 
Published: April 2020

Abstract
Under physiological conditions, fibrinogen receptor integrin αIIbβ3 on the circulating platelets is in a low-affinity, or resting state, unable to bind soluble ligands. During platelet activation by agonists, a cascade of signaling events induces a conformational change in the extracellular domain of αIIbβ3, thereby converting it into a high-affinity state capable of binding ligands through a process known as “inside-out signaling”. What maintains this integrin in a low-affinity state is not well understood. We have previously identified JAM-A, junctional adhesion molecule A, on the platelet surface. We have shown that an antibody blockade of JAM-A dose-dependently activates platelets. To understand the molecular mechanism through which JAM-A regulates platelet aggregation, we used Jam-A null mice. Interestingly, the mouse bleeding times were significantly shortened in Jam-A null mice compared to wildtype littermates. Furthermore, the majority of these mice showed a rebleeding phenotype. This phenotype was further confirmed by FeCl3-induced carotid artery occlusion, a well-accepted in vivo model for thrombosis. Platelets derived from Jam-A-null mice were used to evaluate the role of JAM-A in agonist-induced platelet aggregation. We found that Jam-A null platelets showed enhanced aggregation in response to physiological agonists such as PAR4 peptide, collagen, and ADP as compared to platelets from wildtype littermates. JAM-A was found to associate with αIIbβ3 in unactivated human platelets, but this association was disrupted by both agonist-induced platelet aggregation and during outside-in signaling initiated upon platelet spreading on immobilized Fg. We also found that in resting platelets, JAM-A is phosphorylated on a conserved tyrosine 280 in its cytoplasmic domain, which was dephosphorylated upon platelet activation. Furthermore, JAM-A is rapidly and transiently phosphorylated on serine 284 residue during platelet activation by agonists. Interestingly, JAM-A also formed a complex with Csk, a tyrosine kinase known to be inhibitory to Src activation, in resting platelets. This complex was dissociated upon activation of platelets by agonists. These results suggest that tyrosine-phosphorylated JAM-A recruits Csk to αIIbβ3 in resting platelets, thus maintaining a low-affinity state of integrin αIIbβ3. Agonist–induced activation of platelets results in rapid dephosphorylation of JAM-A on Y280 and phosphorylation on S284 residues. This causes dissociation of JAM-A from integrin αIIbβ3 facilitating platelet aggregation.
Impact of Prior Invasive Pulmonary Aspergillosis (IPA) on Outcome in Patients Receiving Reduced Intensity Conditioning (RIC) Allogeneic Haematopoietic Stem Cell Transplantation (Allo-SCT).
Authors: El-Cheikh Jean , Wang Ling , Esterni Benjamin , Faucher Catherine , Furst Sabine , de Lavallade Hugues , Berger Pierre , Blaise Didier 
Published: April 2020

Abstract
Invasive Pulmonary Aspergillosis (IPA) is a major cause of morbidity in patients with hematological malignancies. The aim of this single centre retrospective study was to determine the impact of prior IPA on outcome after RIC Allo-SCT. All cases of proven or probable IPA diagnosed prior to performance of RIC Allo-SCT at the Paoli-Calmettes Institute Cancer Centre from 1 January 2000 through 31 December 2007 were included. 28 patients were identified among 434 patients undergoing Allo-SCT. Patients’ data were collected from a maintained database and by retrospective clinical chart review. Twenty eight cases were identified. Gender: M/F (16/12); median age at diagnosis was 53 years (18–65). 23 patients (82%) had acute myeloid leukemia. In all patients, IPA was diagnosed according to standard procedures. IPA therapy included: 20 patients (71%) were receiving Voriconazole; 4 patients Itraconazole, and 4 patients with an association of different antifungal drugs including Caspofungine, Liposomal Amphoteracine-B, or Posaconazole. The median duration of treatment prior to RIC was 8 months range (1–16). The median time between the diagnosis of IPA and transplantation was 6 months (1–27); 20 patients (71%) received a graft from a family donor, 4 patients had a MUD, and 4 patients received cord blood cells donors. 21 patients (75%) received a conditioning regimen with Fludarabine Busulfan and ATG, and 4 patient (14%) received a conditioning with Fludarabine Cyclophosphamide and TBI, 3 patients (11%) Fludarabine and TBI, Most patients (n=25; 89%) received or continued a secondary prophylaxis against aspergillosis at time of Allo-SCT: 17 (68%) had a prophylaxis with Voriconazole; 3 patients Itraconazole, 2 patients Posaconazole. After RIC transplantation only 4 patients (14%) had reactivation of their IPA. The latter 4 patients were experiencing severe acute GVHD treated with high dose corticosteroids. None of these patients died of IPA. Actually 18 patients (64%) are still alive with a median follow up of 23.5 months (12.6–48.5). Overall survival at 2 years was 59% [95%CI, 43–83]. In all, 3 patients died from other causes not directly related to IPA, 2 patients because of relapse or disease progression, and one due extensive chronic GVHD. In comparison to literature in standard myéloablative allo-SCT setting, these data suggest that adequately treated and controlled IPA prior to RIC Allo-SCT do not worsen outcome. The latter is likely due to multiple changes in transplantation practice, including the RIC nature of the conditioning regimens, the infusion of peripheral blood stem cells, rapid diagnosis of IPA, and use of modern efficient antifungal drugs.
Integrated Genomic Profiling Identifies Preferential Expression of the Insulin Receptor in CLL with Deletion 11q.
Authors: Malek Sami , Ouillette Peter , Shedden Kerby , Saiya-Cork Kamlai 
Published: April 2020

Abstract
Chronic lymphocytic leukemia (CLL) is associated with characteristic genomic aberrations as defined by FISH and SNP arrays. CLL with del11q is characterized by a relatively aggressive clinical course, and about one third of cases carry mutations in ATM on the retained allele. Little information is available on additional molecular aberrations associated with del11q in CLL. We have analyzed del11q in a subset of 178 CLL cases using DNA from FACS-sorted CD19+ cells compared with buccal DNA using the Affymetrix 50k SNP array platform. Genomic copy number analysis using dChipSNP identified two non-overlapping minimal deleted regions on 11q, one of which spans ATM. We proceeded to use comparative expression array profiling of RNA derived from sorted CD19+ cells from 10 CLL cases with and nine cases without del11q using the Affymetrix U133 2.0 Plus platform. Analysis of normalized data identified ~85 probe sets with differential expression (del11q versus reference) that displayed a false discovery rate of &lt;0.1. Approximately 70% of these genes were under-expressed and mapped to 11q22–23, thus providing confidence that genes lost through del11q displayed reduced expression under our assay conditions. Three probe sets identified the insulin receptor (INSR) to be expressed at substantially higher levels (log2 scale 2.5–3.1 fold) in del11q CLL as opposed to the reference cases that were used in the expression array-based analysis. Validation of differential INSR expression in CLL was accomplished by Q-PCR using cDNA synthesized from RNA purified from sorted CD19+ cells from 178 CLL cases. Using normalized Ct values for INSR expression (delta Ct INSR-GAPD) and a delta Ct cut-off of &lt;10, 65% of CLL with del11q expressed the INSR as opposed to 15% (del13q14), 6% (del17p), 11% (normal FISH) and 23% (trisomy 12) and ~20% of all CLL cases, independent of genetic subtype. Finally, immunoblot analysis on cellular lysates derived from negatively enriched and &gt;90% pure CLL cells from 10 cases with del11q and with high INSR expression versus cases without del11q and absent expression confirmed the accuracy of Q-PCR-based estimates of INSR expression. Work is in progress to measure effects of INSR expression on CLL survival and insulin-induced signaling in CLL in an effort to dissect functional consequences of INSR expression in CLL.
Patients with Severe Factor XI Deficiency Who Have An Inhibitor or IgA Deficiency Can Undergo Uneventful Major Surgery by a Single Infusion of Low Dose Recombinant Factor VIIa and Use of Tranexamic Acid.
Authors: Salomon Ophira , Tamarin Ilia , Livnat Tami , Horovitz Zeev , Kuriansky Joseph , Martinowitz Uriel , Mor Yoram , Seligsohn Uri 
Published: April 2020

Abstract
Inhibitors to factor XI (FXI) can develop following exposure to plasma products in 33% of patients with severe FXI deficiency who are homozygous for the type II nonsense mutation prevalent in Jews (Salomon et al. Blood2003;101:4783). Hemostasis in five such patients was previously achieved during surgery by infusion of recombinant factor VIIa (rFVIIa) and tranexamic acid, but two patients experienced arterial thrombosis following surgery (Schulman et al. Hemophilia2006; 12:223). Conceivably, the rather high dose of rFVIIa used was responsible for the thrombotic events in these patients. In a previous in vitro study, we showed that low concentrations of rFVIIa can correct thrombin generation in plasma of patients with severe FXI deficiency and an inhibitor to FXI (Livnat et al. J Thromb Hemost2006; 4:192). In the present study we addressed the question whether low doses of rFVIIa and use of tranexamic would be hemostatically effective and less thrombogenic during and after major surgery in patients with severe FXI deficiency in whom plasma derivatives could not be used. Three patients (two with FXI inhibitor and one with severe IgA deficiency) underwent major surgery managed by a single low dose infusion of rFVIIa and administration of tranexamic acid 1 G q.i.d for 7 days (Table). In patient 1 the infusion was given immediately prior to surgery and in patients 2 and 3 at the end of surgery. Hemostasis was achieved in all patients and no thrombosis occurred.
No. Sex/age FXI (U/dL) FXI inhibitor (B.U) Operation Single dose rVIIa (uG/Kg) Adverse events * IgA deficiency 1 M/62 &lt; 0.01 5.0 Laparoscopic cholecystectomy 30 None 2 M/61 &lt; 0.01 5.0 Transuretheral prostatectomy 16 None 3 M/63 0.02 0* Parathyroidectomy 15 None
These observations suggest that a single infusion of low dose rFVIIa and use of tranexamic acid can be a safe modality of treatment in patients with severe FXI deficiency who cannot receive blood products. Furthermore, the protocol outlined here may be used to avoid inhibitor formation in patients with extremely severe FXI deficiency who undergo surgery.
Glia Maturation Factor-Gamma Mediates Neutrophil Chemotaxis Via p38 MAPK and PTEN.
Authors: Aerbajinai Wulin , Chin Kyung , Zhu Jianqiong , Li Hongzhen , Rodgers Griffin P 
Published: April 2020

Abstract
Cellular chemotaxis is a fundamental process in which cells migrate directionally when they are exposed to external chemical gradients. Recent progress has been made in defining the molecular mechanisms that regulate chemoattractant-induced cell polarity and chemotaxis, including the contribution of p38 MAPK and PTEN dependent migration of neutrophils toward their end target chemoattractants. However, it remains unclear how chemoattractant stimulation regulates F-actin dynamics and PTEN localization in migrating neutrophils. Glia maturation factor (GMFG) is a highly conserved protein expressed mainly in the blood and immune systems. Our lab previously reported that GMFG is upregulated in granulocyte-colony stimulating factor (G-CSF)-induced differentiated myeloid cells (Shi Y, et al, Genomics Proteomics Bioinformatics. 2006 Aug;4(3):145–55). Furthermore, while recent studies indicate that GMFG is involved in the regulation of actin cytoskeleton reorganization in microendothelial cells, little is known about the role of GMFG in hematopoietic myeloid cells. In this study, we investigated the role of GMFG in the chemotaxis of differentiated neutrophil-like HL-60 cells and how GMFG mediated neutrophils chemotaxis occurs in response to chemotactic signals. We have now shown that small interfering RNA-mediated depletion of GMFG expression in differentiated neutrophil-like HL-60 cells exhibit greater than 75% inhibition of basal cell migration, that could not be rescued in the presence of chemoattractant FMLP, but could rescued by IL-8. These data suggest that an endogenous expression of GMFG is required for chemotaxis toward end target chemoattractant FMLP, but not for toward intermediate chemokines IL-8. Moreover, immunofluorescence assay shows that gene silencing of GMFG abolished FMLP-induced the phosphorylation of p38 MAPK, localization of phosphatase PTEN, and F-actin reorganization. In contrast, transient overexpression of GMFG in K562 cells significantly enhanced basal cell migration by 2 fold (P=0.01) and chemotaxis toward FMLP by 2.2 fold (P=0.04), but there was no change with IL-8 stimulation. The overexpression of GMFG caused the activation of p38 MAP kinase and increased F-actin expression in the absence of fMLP stimulation. Pretreatment with p38 MAPK inhibitor SB203580 completely blocked the GMFG-dependent activation of p38 MAPK and enhanced expression of F-actin as well as cell migration. These results suggest that GMFG-induced cell migration in K562 cells is depending on p38 MAPK via F-actin reorganization. Taken together, our findings identify GMFG as a novel factor that mediates the FMLP-induced p38-dependent signal pathway leading to PTEN redistribution and F-actin reorganization during migrating neutrophils toward end target stimulation. These data, if confirmed, implicates GMFG as a potential target for therapeutic intervention in disorders associated with enhanced and pathological neutrophil infiltration.
Phase 1 Clinical Testing of HQK-1001, a Novel Oral Fetal Globin Gene Inducer
Authors: Perrine Susan , Welch William C , Keefer Jeffrey , Downey Robin L , Boosalis Michael S , Case Sally , Faller Douglas V , Berenson Ronald 
Published: April 2020

Abstract
Development of non-cytotoxic, orally-active therapeutics, which induce fetal globin production, would be beneficial for treatment of beta-thalassemias and hemoglobinopathies. The short-chain fatty acids (SCFA) butyrate and phenylbutyrate are active fetal globin inducers, but their clinical application has been limited by inhibition of erythropoiesis and unfavorable PK profiles. HQK-1001 is a SCFA which stimulates fetal globin gene expression in reporter gene assays, erythroid progenitors, transgenic mice, and anemic baboons. HQK-1001 also stimulates human erythroid progenitor (BFU-E) proliferation by a mean of 30% above controls, and increased red blood cell counts in phlebotomized baboons. HQK-1001 has demonstrated a wide safety margin in pre-clinical toxicology testing, with no significant adverse effects in sub-chronic (6-month) studies and negative mutagenicity testing. Based on these pre-clinical data, a placebo-controlled, randomized, blinded, single-dose escalating Phase 1 trial was conducted to evaluate HQK-1001 at 4 dose levels ranging from 2 to 20 mg/kg in 32 normal volunteers. The drug was welltolerated, with no significant adverse events. Pharmacokinetic analyses showed low intersubject variability, a linear increase in Cmax and AUC with increasing dose, and T½ of 11 hours, indicating suitability for once-daily dosing. Administration under fed conditions demonstrated equivalent AUC to fasting conditions. In a subsequent 14-day Phase 1 dosing study in 41 normal subjects, the drug was also well-tolerated, with no significant adverse effects at the studied dose levels (5, 10 and 15 mg/kg). F-reticulocytes increased in subjects treated with 5 to 10 mg/kg doses. Absolute reticulocytes increased significantly above baseline (p &lt;0.02 – 0.002) following 14-day dosing at all dose levels, while no significant change occurred in placebo controls. These first-in-human clinical studies demonstrating safety of HQK-1001 in 73 normal volunteer subjects and an improved pharmacologic profile over prior SCFAs indicate that HQK-1001 merits further clinical investigation in anemic patients with beta-globin gene disorders.
Impact of Management of Iron Overload in Patients with Myelodsplastic Syndromes
Authors: Bozkaya Duygu , Migliaccio-Walle Kristen , Baladi Jean-Franòois 
Published: April 2020

Abstract
For many patients with myelodysplastic syndromes (MDS) chronic red blood cell transfusion is the standard of care to delay or prevent disease progression and to improve function. This is not without consequence, however, as transfusion-dependent patients are at risk for developing iron overload, potentially leading to cardiac disease, diabetes and hepatic complications. Iron chelators have been widely applied to remove excess iron from the body. Once-daily deferasirox given orally achieves iron reduction with easy administration. The purpose of the study was to develop a model to compare the impact of choosing deferasirox versus no chelation in managing transfusion-dependent patients with MDS. Mortality, progression to acute myeloid leukemia (AML), and development of complications related to iron overload were central elements of this model. Simulated patients were individually subject to these risks, dependent on use of chelation. The analysis was stratified by patients’ age group (≤77, &gt;77) and by severity of MDS (Low, Int-1, Int-2 and High) as defined by the International Prognostic Scoring System (IPSS). Event risks, utilities associated with chelation and complication status were obtained from published or presented sources and deferasirox study data. The improved rates with deferasirox versus no chelation for mortality and progression to AML were taken from recent studies by Rose et al and Leitch, respectively. Complication rates for patients receiving transfusion, and the deferasirox-related reduction in these rates, were obtained from the literature. The cost of deferasirox and management costs were estimated from data obtained from literature and other US cost data sources. All costs are reported in 2008 US$. Utility values associated with deferasirox and no chelation were calculated as 0.74 and 0.67 using SF-36 measures from a substudy of a 1-year, open-label, single-arm, multi-center trial evaluating the efficacy and safety of oral chelation therapy. Costs and benefits were discounted at 3% per year. Univariate sensitivity analyses were implemented. Initial 10-year results estimated a cost per patient of $217,785 with deferasirox and $120,505 with no chelation. Deferasirox management resulted in 4.94 years survival (discounted) and 3.18 QALYs per patient. Compared with no chelation, deferasirox yielded an additional 1.63 years survival and 1.42 QALY. Resultant cost-effectiveness ratio was $68,699/QALY gained. Results of sensitivity analyses and other scenarios predicted a cost/QALY as low as $44,068. Chelation therapy with deferasirox is predicted to result in improved survival and substantially fewer complications due to excess iron accumulation in the range of accepted cost/QALY.
In Vivo Injection of Synthetic Small Interfering RNA to Lethally Irradiated Mouse as a New Model to Study Apoptotic Pathways.
Authors: Drouet Michel , Garrigou Philippe , Mayol Jean-François , Delaunay Christophe , Peinnequin Andre , Hérodin Francis 
Published: April 2020

Abstract
The Fas/Fas-ligand system is a well known component of the extrinsic apoptotic pathway. Using a short term culture assay we have established that CD34+ hematopoietic stem and progenitor cells express Fas antigen within 10 hours following irradiation. Using the terminaldeoxynucleotidyl transferase test, we have also established that this expression was linked with apoptosis since only the Fas/Fas-ligand positive cells exhibited a high level of DNA fragmentation (Drouet et al, Stem cell 1999). However Fas is also involved in the CD34+ cells differentiation process as described in ex vivo expansion studies. Caspases are other important actors of radiation induced (RI) apoptosis process and our team has recently identified caspases one and six as key actors in RI apoptosis in CD34+ cells. The goal of the present study was to evaluate short term synthetic small interfering RNA (siRNA) as new tools to in vivo modulate apoptosis in order to allow pathophysiological studies at the hematopoietic niche level. Briefly, B6D2F1 mice were globally irradiated (9 Gy gamma, LD90% 30 days) and then injected at 2 hours following irradiation with siRNA (0.5 nmol/mice, Dharmacon). To ensure a proper delivery to the niche cell components, siRNA were intra-tibially injected under a volume of 30μl. The duration of gene inhibition is about 10 days long. Control mice were injected with non relevant mock siRNA (n=80). Treated animals were injected with Fas-siRNA (n=20) or Fas + a pool of siRNA against caspases 1+ 3 + 6 + 8)(n=20). All mice were given ciprofloxacin during a week and no early lethality was observed. The lethality curves show that animals treated with Fas-siRNA exhibited an accelerated death rate when compared with siRNA mice. These results are compatible with a janus model for Fas expression depending on the time following irradiation: initial proapoptotic role, then requirement for cell expansion. Globally this study suggests the feasibility of using synthetic siRNA in vivo to screen the role of apoptosis actors.