bluuebunny/crossref_metadata_2025_split huggingface dataset:
Formation of Dense Erythrocytes in SAD Mice Exposed to Chronic Hypoxia: Evaluation of Different Therapeutic Regimens and of a Combination of Oral Clotrimazole and Magnesium Therapies
Authors: De Franceschi Lucia , Brugnara Carlo , Rouyer-Fessard Philippe , Jouault Helene , Beuzard Yves 
Published: October 2019

AbstractWe have examined the effect of hydroxyurea (HU), clotrimazole (CLT), magnesium oxide (Mg), and combined CLT+Mg therapies on the erythrocyte characteristics and their response to chronic hypoxia in a transgenic sickle mouse (SAD) model. SAD mice were treated for 21 days with 1 of the following regimens (administered by gavage): control (n = 6), HU (200 mg/d; n = 6), CLT (80 mg/kg/d, n = 5), Mg (1,000 mg/kg/d, n = 5), and CLT+Mg (80 and 1,000 mg/kg/d, respectively, n = 6). Nine normal mice were also treated as controls (n = 3), HU (n = 3), and CLT+Mg (n = 3). Treatment with HU induced a significant increase in mean corpuscular volume and cell K content and a decrease in density in SAD mice. Treatment with the CLT and Mg, either alone or in combination, also increased cell K and reduced density in SAD mice. After 21 days of treatment, the animals were exposed to hypoxia (48 hours at 8% O2) maintaining the same treatment. In the SAD mice, hypoxia induced significant cell dehydration. These hypoxia-induced changes were blunted in either HU- or Mg-treated SAD mice and were completely abolished by either CLT or CLT+Mg treatment, suggesting a major role for the Gardos channel in hypoxia-induced dehydration in vivo.
Ontogeny of Catecholamine and Adenosine Receptor-Mediated cAMP Signaling of Embryonic Red Blood Cells: Role of cGMP-Inhibited Phosphodiesterase 3 and Hemoglobin
Authors: Baumann Rosemarie , Blass Christian , Götz Robert , Dragon Stefanie 
Published: October 2019

Abstract
We have previously shown that the cAMP signaling pathway controls major aspects of embryonic red blood cell (RBC) function in avian embryos (Glombitza et al, Am J Physiol 271:R973, 1996; and Dragon et al, Am J Physiol 271:R982, 1996) that are important for adaptation of the RBC gas transport properties to the progressive hypercapnia and hypoxia of later stages of avian embryonic development. Data about the ontogeny of receptor-mediated cAMP signaling are lacking. We have analyzed the response of primitive and definitive chick embryo RBC harvested from day 3 to 18 of development towards forskolin, β-adrenergic, and A2 receptor agonists. The results show a strong response of immature definitive and primitive RBC to adenosine A2 and β-adrenergic receptor agonists, which is drastically reduced in the last stage of development, coincident with the appearance of mature, transcriptionally inactive RBC. Modulation of cGMP-inhibited phosphodiesterase 3 (PDE3) has a controlling influence on cAMP accumulation in definitive RBC. Under physiological conditions, PDE3 is inhibited due to activation of soluble guanylyl cyclase (sGC). Inhibition of sGC with the specific inhibitor ODQ decreases receptor-mediated stimulation of cAMP production; this effect is reversed by the PDE3 inhibitor milrinone. sGC is acitivated by nitric oxide (NO), but we found no evidence for production of NO by erythrocyte NO-synthase. However, embryonic hemoglobin releases NO in an oxygen-linked manner that may activate guanylyl cyclase.
The Risk of Residual Molecular and Cytogenetic Disease in Patients With Philadelphia-Chromosome Positive First Chronic Phase Chronic Myelogenous Leukemia Is Reduced After Transplantation of Allogeneic Peripheral Blood Stem Cells Compared With Bone Marrow
Authors: Elmaagacli Ahmet H. , Beelen Dietrich W. , Opalka Bertram , Seeber Siegfried , Schaefer Ulrich W. 
Published: October 2019

AbstractThe detection of residual molecular and cytogenetic disease was prospectively compared in patients with Philadelphia-chromosome (Ph1) positive first chronic phase chronic myelogenous leukemia (CML) who underwent allogeneic transplantation of unmanipulated peripheral blood stem cells (PBSCT) (n = 29) or bone marrow (BM) (n = 62) using genotypically HLA-identical sibling donors or partially HLA-matched extended family donors. A molecular relapse (MR), as defined by two consecutive positive polymerase chain reaction (PCR) assays for the detection of M-bcr-abl transcripts in a 4-week interval, was found in two of 29 (7%) patients after PBSCT compared with 20 of 62 (32%) patients after bone marrow transplantation (BMT). This corresponds to a 4-year molecular relapse estimate (± standard error) of 7% ± 5% after PBSCT and of 44% ± 8% after BMT (P &lt; .009). With identical follow-up periods of survivors in both patient subsets between 6 and 55 months (median, 28 months), 14 of the 20 patients with MR after BMT progressed to an isolated cytogenetic (n = 10) or a hematologic (n = 4) disease recurrence, resulting in a 4-year cytogenetic relapse estimate of 47% ± 11%, while none of the patients after PBSCT has so far relapsed (P &lt; .006). Multivariate analysis including all potential influencial factors of posttransplant disease recurrence identified the source of stem cells (P &lt; .02) as the only independent predictor of molecular relapse. In conclusion, this prospective comparison of molecular and cytogenetic residual disease demonstrates that peripheral blood stem cell transplants have a more pronounced activity against residual CML cells than bone marrow transplants. Prospective randomized trials comparing PBSCT and BMT in patients with first chronic phase Ph1-positive CML are strictly required to further substantiate differences in the antileukemic activity of the two stem cell sources.
Murine Stromal Cells Counteract the Loss of Long-Term Culture-Initiating Cell Potential Induced by Cytokines in CD34+CD38low/neg Human Bone Marrow Cells
Authors: Bennaceur-Griscelli Annelise , Tourino Cristina , Izac Brigitte , Vainchenker William , Coulombel Laure 
Published: October 2019

AbstractEvidence has been provided recently that shows that high concentrations of cytokines can fulfill functions previously attributed to stromal cells, such as promote the survival of, and led to a net increase in human primitive progenitors initiating long-term cultures in vitro (LTC-IC) or engrafting NOD-SCID (nonobese diabetic severe-combined immunodeficient) recipients in vivo. These data prompted us to re-evaluate whether stromal cells will further alter the properties of primitive progenitor cells exposed to cytokines. Single CD34+CD38low and CD38neg cells were incubated 10 days in serum-containing or serum-free medium in the presence or in the absence of murine marrow-derived stromal cells (MS-5). Recombinant human cytokines stem cell factor (SCF), pegylated-megakaryocyte growth and differentiation factor (PEG–MGDF), FLT3-L, Interleukin (IL)-3, IL-6, and granulocyte-macrophage colony-stimulating factor (GM–CSF) were systematically added at various concentrations (10 to 300 ng/mL). Cell proliferation and LTC-IC potential were evaluated in each clone after 10 days. A striking and consistent observation was the retention of a high LTC-IC potential in clones exposed to cytokines in the presence of stromal feeders, whereas clones exposed to cytokines alone in the absence of stromal feeders rapidly lost their LTC-IC potential as they proliferated. This was reflected both by the higher proportion of wells containing LTC-IC and by the high numbers of CFC produced after 5 weeks in clones grown with MS-5 during the first 10 days. We further showed by analyzing multiple replicates of a single clone at day 10 that MS-5 cells promoted a net increase in the LTC-IC compartment through self-renewal divisions. Interestingly, these primitive LTC-IC were equally distributed among small and large clones, as counted at day 10, indicating that active proliferation and loss of LTC-IC potential could be dissociated. These observations show that, in primitive cells, stromal cells counteract differentiation events triggered by cytokines and promoted self-renewal divisions. Furthermore, the almost identical distribution of the size of the clones with or without MS-5 suggests that proliferation and function of human primitive cells may be independently regulated by external signals, and that the former is primarily under the control of cytokines.
The Receptor Protein Tyrosine Phosphatase, PTP-RO, Is Upregulated During Megakaryocyte Differentiation and Is Associated With the c-Kit Receptor
Authors: Taniguchi Yoshitaka , London Roanna , Schinkmann Karin , Jiang Shuxian , Avraham Hava 
Published: October 2019

AbstractWe have recently isolated a cDNA encoding a novel human receptor-type tyrosine phosphatase, termed PTP-RO (for a protein tyrosine phosphatase receptor omicron), from 5-fluorouracil–treated murine bone marrow cells. PTP-RO is a human homologue of murine PTPλ and is related to the homotypically adhering κ and μ receptor-type tyrosine phosphatases. PTP-RO is expressed in human megakaryocytic cell lines, primary bone marrow megakaryocytes, and stem cells. PTP-RO mRNA and protein expression are upregulated upon phorbol 12-myristate 13-acetate (PMA) treatment of the megakaryocytic cell lines CMS, CMK, and Dami. To elucidate the function of PTP-RO in megakaryocytic cells and its potential involvement in the stem cell factor (SCF)/c-Kit receptor pathway, COS-7 and 293 cells were cotransfected with the cDNAs of both the c-Kit tyrosine kinase receptor and PTP-RO. PTP-RO was found to be associated with the c-Kit receptor in these transfected cells and the SCF/Kit ligand induced a rapid tyrosine phosphorylation of PTP-RO. Interestingly, these transfected cells demonstrated a decrease in their proliferative response to the SCF/Kit ligand. In addition, we assessed the association of PTP-RO with c-Kit in vivo. The results demonstrated that PTP-RO associates with c-Kit but not with the tyrosine kinase receptor FGF-R and that PTP-RO is tyrosine-phosphorylated after SCF stimulation of Mo7e and CMK cells. Antisense oligonucleotides directed against PTP-RO mRNA sequences significantly inhibited megakaryocyte progenitor proliferation. Therefore, these data show that the novel tyrosine kinase phosphatase PTP-RO is involved in megakaryocytopoiesis and that its function is mediated by the SCF/c-Kit pathway.
The Glucocorticoid Receptor Cooperates With the Erythropoietin Receptor and c-Kit to Enhance and Sustain Proliferation of Erythroid Progenitors In Vitro
Authors: von Lindern Marieke , Zauner Wolfgang , Mellitzer Georg , Steinlein Peter , Fritsch Gerhard , Huber Klaus , Löwenberg Bob , Beug Hartmut 
Published: October 2019

AbstractAlthough erythropoietin (Epo) is essential for the production of mature red blood cells, the cooperation with other factors is required for a proper balance between progenitor proliferation and differentiation. In avian erythroid progenitors, steroid hormones cooperate with tyrosine kinase receptors to induce renewal of erythroid progenitors. We examined the role of corticosteroids in the in vitro expansion of primary human erythroid cells in liquid cultures and colony assays. Dexamethasone (Dex), a synthetic glucocorticoid hormone, cooperated with Epo and stem cell factor to induce erythroid progenitors to undergo 15 to 22 cell divisions, corresponding to a 105- to 106-fold amplification of erythroid cells. Dex acted directly on erythroid progenitors and maintained the colony-forming capacity of the progenitor cells expanded in liquid cultures. The hormone delayed terminal differentiation into erythrocytes, which was assayed by morphology, hemoglobin accumulation, and the expression of genes characteristic for immature cells. Sustained proliferation of erythroid progenitors could be induced equally well from purified erythroid burst-forming units (BFU-E), from CD34+ blast cells, and from bone marrow depleted from CD34+ cells.
C/EBP Bypasses Granulocyte Colony-Stimulating Factor Signals to Rapidly Induce PU.1 Gene Expression, Stimulate Granulocytic Differentiation, and Limit Proliferation in 32D cl3 Myeloblasts
Authors: Wang Xinping , Scott Edward , Sawyers Charles L. , Friedman Alan D. 
Published: October 2019

AbstractWithin hematopoiesis, C/EBP is expressed only in myeloid cells, and PU.1 is expressed mainly in myeloid and B-lymphoid cells. C/EBP-deficient mice lack the neutrophil lineage and retain monocytes, whereas PU.1-deficient mice lack monocytes and have severely reduced neutrophils. We expressed a C/EBP-estrogen receptor ligand-binding domain fusion protein, C/EBPWT-ER, in 32D cl3 myeloblasts. 32D cl3 cells proliferate in interleukin-3 (IL-3) and differentiate to neutrophils in granulocyte colony-stimulating factor (G-CSF). In the presence of estradiol, C/EBPWT-ER induced morphologic differentiation and the expression of the myeloperoxidase, lactoferrin, and G-CSF receptor mRNAs. C/EBPWT-ER also induced a G1/S cell cycle block, with induction of p27 and Rb hypophosphorylation. bcr-ablp210 prevented 32D cl3 cell differentiation. Activation of C/EBP-ER in 32D-bcr-ablp210 or Ba/F3 B-lymphoid cells induced cell cycle arrest independent of terminal differentiation. C/EBPWT-ER induced endogenous PU.1 mRNA within 8 hours in both 32D cl3 and Ba/F3 cells, even in the presence of cycloheximide, indicating that C/EBP directly activates the PU.1 gene. However, activation of a PU.1-ER fusion protein in 32D cl3 cells induced myeloperoxidase (MPO) RNA but not terminal differentiation. Thus, C/EBP acts downstream of G-CSF and upstream of PU.1, p27, and potentially other factors to induce myeloblasts to undergo granulocytic differentiation and cell cycle arrest.
Amino Acid Sequence of Trocarin, a Prothrombin Activator FromTropidechis carinatus Venom: Its Structural Similarity to Coagulation Factor Xa
Authors: Joseph Jeremiah S. , Chung Maxey C.M. , Jeyaseelan Kandiah , Kini R. Manjunatha 
Published: October 2019

AbstractAmong snake venom procoagulant proteins, group II prothrombin activators are functionally similar to blood coagulation factor Xa. We have purified and partially characterized the enzymatic properties of trocarin, the group II prothrombin activator from the venom of the Australian elapid, Tropidechis carinatus (rough-scaled snake). Prothrombin activation by trocarin is enhanced by Ca2+, phospholipids, and factor Va, similar to that by factor Xa. However, its amidolytic activity on peptide substrate S-2222 is significantly lower. We have determined the complete amino acid sequence of trocarin. It is a 46,515-Dalton glycoprotein highly homologous to factor Xa and shares the same domain architecture. The light chain possesses an N-terminal Gla domain containing 11 γ-carboxyglutamic acid residues, followed by two epidermal growth factor (EGF)-like domains; the heavy chain is a serine proteinase. Both chains are likely glycosylated: the light chain at Ser 52 and the heavy chain at Asn 45. Unlike other types of venom procoagulants, trocarin is the first true structural homologue of a coagulation factor. It clots snake plasma and thus may be similar, if not identical, to snake blood coagulation factor Xa. Unlike blood factor Xa, it is expressed in high quantities and in a nonhepatic tissue, making snake venom the richest source of factor Xa-like proteins. It induces cyanosis and death in mice at 1 mg/kg body weight. Thus, trocarin acts as a toxin in venom and a similar, if not identical, protein plays a critical role in hemostasis.
Idiotype Vaccination in Human Myeloma: Generation of Tumor-Specific Immune Responses After High-Dose Chemotherapy
Authors: Massaia Massimo , Borrione Paolo , Battaglio Silvano , Mariani Sara , Beggiato Eloise , Napoli Patrizia , Voena Claudia , Bianchi Alberto , Coscia Marta , Besostri Barbara , Peola Silvia , Stiefel Thomas , Even Jos , Novero Domenico , Boccadoro Mario , Pileri Alessandro 
Published: October 2019

AbstractIgs contain unique portions, collectively termed idiotypes (Id), that can be recognized by the immune system. Id expressed by tumor cells in B-cell malignancies can be regarded as tumor-specific antigens and a target for vaccine immunotherapy. We have started a vaccination trial in multiple myeloma (MM) using Id-specific proteins conjugated to keyhole limpet hemocyanin (KLH) as immunogens and low doses of subcutaneous granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-2 (IL-2) as immunoadjuvants. Twelve patients who had previously been treated with high-dose chemotherapy followed by peripheral blood progenitor cell (PBPC) transplantation entered this study from August 1995 to January 1998. All patients were in first remission at the time of vaccination. They received subcutaneous injections of Id vaccines and immunoadjuvants in an outpatient setting. The generation of Id-specific T-cell proliferative responses was documented in 2 patients, whereas a positive Id-specific delayed-type hypersensitivity (DTH) reaction was observed in 8 of the 10 patients studied. DTH specificity was confirmed in 1 patient by investigating the reactivity to synthetic peptides derived from the VDJ sequence of the tumor-specific Ig heavy chain. None of the patients generated soluble immune responses to Id, whereas the generation of soluble and cellular immune responses to KLH was observed in 100% and 80%, respectively. Eleven patients completed the treatment, whereas 1 patient failed to finish owing to progression of disease. Freedom from disease progression (FFDP), measured from the date of first Id/KLH injection to the date of first treatment after vaccination or last follow-up, ranged from 9 to 36 months. These data indicate that the immune competence status of MM patients is still susceptible to specific immunization after high-dose chemotherapy and PBPC transplantation. It remains to be determined whether generation of Id-specific immune responses can reduce the relapse rate of patients with minimal residual disease.
Detection of t(4;14)(p16.3;q32) Chromosomal Translocation in Multiple Myeloma by Double-Color Fluorescent In Situ Hybridization
Authors: Finelli Palma , Fabris Sonia , Zagano Savina , Baldini Luca , Intini Daniela , Nobili Lucia , Lombardi Luigia , Maiolo Anna Teresa , Neri Antonino 
Published: October 2019

Abstract
Chromosomal translocations involving the immunoglobulin heavy chain (IGH) locus at chromosome 14q32 represent a common mechanism of oncogene activation in lymphoid malignancies. In multiple myeloma (MM), variable chromosome partners have been identified by conventional cytogenetics, including the 11q13, 8q24, 18q21, and 6p21 loci. We and others have recently reported a novel, karyotypically undetectable chromosomal translocation t(4;14)(p16.3;q32) in MM-derived cell lines, as well as in primary tumors. The 4p16.3 breakpoints are relatively scattered and located less than 100 kb centromeric of the fibroblast growth factor receptor 3 (FGFR3) gene or within the recently identified WHSC1 gene, both of which are apparently deregulated by the translocation. To assess the frequency of the t(4;14)(p16.3;q32) translocation in MM, we performed a double-color fluorescent in situ hybridization (FISH) analysis of interphase nuclei with differently labeled probes specific for the IGH locus (a pool of plasmid clones specific for the IGH constant regions) or 4p16.3 (yeast artificial chromosome (YAC) 764-H1 spanning the region involved in breakpoints). Thirty MM patients, the MM-derived cell lines KMS-11 and OPM2, and six normal controls were examined. The identification of a t(4;14) translocation, evaluated as the presence of a der(14) chromosome, was based on the colocalization of signals specific for the two probes; a cutoff value of 15% (mean + 3 standard deviation [SD]) derived from the interphase FISH of the normal controls (range, 5% to 11%; mean ± SD, 8.16 ± 2.2) was used for the quantification analysis. In interphase FISH, five patients (one in clinical stage I, two in stage II, one in stage III, and a plasma cell leukemia) were found to be positive (≈15%). FISH metaphases with split or colocalized signals were detected in only two of the translocated cases and confirmed the pattern found in the interphase nuclei. Furthermore, in three of the five cases with the translocation, FISH analysis with the IGH joining probe (JH) showed the presence of the reciprocal product of the translocation [der(4) chromosome]. Overall, our study indicates that the t(4;14)(p16.3;q32) chromosomal translocation is a recurrent event in MM tumors and may contribute towards the detection of this lesion and our understanding of its pathogenetic and clinical implications in MM.
Overexpression of Wild-Type Retinoic Acid Receptor  (RAR) Recapitulates Retinoic Acid-Sensitive Transformation of Primary Myeloid Progenitors by Acute Promyelocytic Leukemia RAR-Fusion Genes
Authors: Du Changchun , Redner Robert L. , Cooke Michael P. , Lavau Catherine 
Published: October 2019

AbstractRetinoic acid receptor  (RAR) is the target of several chromosomal translocations associated with acute promyelocytic leukemias (APLs). These rearrangements fuse RAR to different partner genes creating the chimeric proteins: PML-RAR, PLZF-RAR, and NPM-RAR. Although the vast majority of APLs respond to retinoic acid therapy, those associated with PLZF-RAR are resistant. We have used retroviruses to express PML-RAR, PLZF-RAR, NPM-RAR, RAR403 (a dominant negative mutant of RAR), and wild-type RAR in murine bone marrow progenitors and found that all of these constructs blocked differentiation and led to the immortalization of myeloid progenitors. This cellular transformation is specific to an alteration of the RAR pathway because overexpression of RARβ, RARγ, or RXR did not result in similar growth perturbations. Pharmacological doses of RA induced differentiation and inhibited proliferation of cells transformed with either of the APL fusion genes, including PLZF-RAR, whereas physiological retinoic acid concentrations were sufficient to reverse the phenotype of cells transformed with wild-type RAR. The cellular responses to retinoic acid were accompanied by a sharp decrease in the amount of the RAR-fusion proteins expressed in the cells. Our findings suggest that the oncogenicity of RAR-fusion proteins results from their nature to behave as unliganded RAR in the presence of physiological concentrations of retinoic acid.
Expression of the Fanconi Anemia Group A Gene (Fanca) During Mouse Embryogenesis
Authors: Abu-Issa Radwan , Eichele Gregor , Youssoufian Hagop 
Published: October 2019

AbstractAbout 80% of all cases of Fanconi anemia (FA) can be accounted for by complementation groups A and C. To understand the relationship between these groups, we analyzed the expression pattern of the mouse FA group-A gene (Fanca) during embryogenesis and compared it with the known pattern of the group-C gene (Fancc). Northern analysis of RNA from mouse embryos at embryonic days 7, 11, 15, and 17 showed a predominant 4.5 kb band in all stages. By in situ hybridization, Fanca transcripts were found in the whisker follicles, teeth, brain, retina, kidney, liver, and limbs. There was also stage-specific variation in Fanca expression, particularly within the developing whiskers and the brain. Some tissues known to express Fancc (eg, gut) failed to show Fancaexpression. These observations show that (1) Fanca is under both tissue- and stage-specific regulation in several tissues; (2) the expression pattern of Fanca is consistent with the phenotype of the human disease; and (3) Fanca expression is not necessarily coupled to that of Fancc. The presence of distinct tissue targets for FA genes suggests that some of the variability in the clinical phenotype can be attributed to the complementation group assignment.