bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of tamoxifen on cell lines displaying the multidrug-resistant phenotype [see comments]
Authors: Berman E , Adams M , Duigou-Osterndorf R , Godfrey L , Clarkson B , Andreeff M 
Published: October 2019

Abstract
We examined the effect of tamoxifen (Tmx), verapamil, and daunorubicin (DNR) in two cell lines that displayed the multidrug-resistant (MDR) phenotype and used laser flow cytometry to quantitate intracellular DNR content. In the vinblastine-resistant human lymphoblastic lymphoma cell line CEM-VBL, simultaneous incubation of DNR with Tmx 10 mumol/L or Tmx 50 mumol/L increased intracellular DNR fluorescence in a dose-dependent manner and demonstrated an uptake pattern similar to that seen with DNR and verapamil. Similar results were obtained in the vincristine- resistant human myeloid leukemia cell line HL-60/RV+. Cellular retention of DNR was also measured in both cell lines and results suggested that continuous exposure of the cells to Tmx resulted in higher intracellular DNR content compared with cells resuspended in fresh medium. No effect of Tmx or verapamil was observed in the drug- sensitive parent cell lines CEM or HL-60. Clonogenic experiments were then performed to determine whether Tmx was itself inhibitory to cell growth or whether Tmx potentiated DNR cytotoxicity. Tmx 10 mumol/L did not significantly inhibit either CEM-VBL or HL-60/RV+ cells after a 3- hour exposure followed by culture in methylcellulose. Tmx 50 mumol/L was significantly more inhibitory in both cell lines. However, cells that had been incubated with DNR and Tmx 10 mumol/L demonstrated a marked increment in growth inhibition compared with cells that had been incubated with DNR alone or Tmx 10 mumol/L alone. Based on the data presented here, we suggest that clinical testing of Tmx and DNR be pursued in the setting where MDR may play a role.
An epitope on the transferrin receptor preferentially exposed during tumor progression in human lymphoma is close to the ligand binding site
Authors: Takahashi S , Esserman L , Levy R 
Published: October 2019

Abstract
We have previously reported an anti-transferrin receptor antibody, Trump, which was originally selected for its ability to discriminate low- and high-grade lymphomas. This feature was distinct from the other anti-transferrin receptor antibodies such as OKT9. In the present study, further immunochemical analysis was performed to define the nature of the antigenic site recognized by the Trump antibody. Trump was found to block the binding of transferrin both to solubilized and to surface transferrin receptors; conversely, transferrin could block the binding of Trump only to surface transferrin receptors. Therefore, the epitope recognized by Trump is near but not identical to the transferrin binding site. Stimulation of peripheral blood lymphocytes with phytohemagglutinin induced both the OKT9 epitope and the Trump epitope, but 12-phorbol 13 myristate acetate induced only the OKT9 epitope. Growth of some cell lines was inhibited by Trump but not by OKT9. No structural difference was found between transferrin receptor molecules reactive with Trump and those reactive with OKT9. In support of these results, Trump was able to immunoprecipitate transferrin receptor molecules solubilized from low-grade follicular lymphoma cells even though it did not bind to the receptors exposed on the surface of these cells. These findings imply that low-grade lymphoma cells differ from high-grade lymphoma cells not in the structures of their transferrin receptors but in their exposure of the molecule on the cell surface.
Transmembrane mobility of phospholipids in sickle erythrocytes: effect of deoxygenation on diffusion and asymmetry
Authors: Blumenfeld N , Zachowski A , Galacteros F , Beuzard Y , Devaux PF 
Published: October 2019

Abstract
We studied the effect of sickling on the transmembrane reorientation and distribution of phospholipids in the red blood cells of patients homozygous for sickle cell anemia (SS). To this purpose, we followed the redistribution kinetics of trace amounts of spin-labeled analogues of natural phospholipids first introduced in the membrane outer leaflet of normal or sickle erythrocytes exposed to air or nitrogen. Deoxygenation had no effect on the lipid redistribution kinetics in normal (AA) cell membranes. At atmospheric pO2, unfractionated SS cells were not different from normal cells. However, on deoxygenation inducing sickling, phosphatidylcholine passive diffusion was accelerated and the rate of the adenosine triphosphate-dependent transport of aminophospholipids was reduced, especially for phosphatidylserine. The stationary distribution of the aminophospholipids between the two leaflets was slightly less asymmetric, a phenomenon more pronounced with phosphatidylethanolamine. These changes were rapidly reversible on reoxygenation. When SS cells were separated by density, both dense and light cells exhibited the properties cited above. However, dense cells exposed to air possessed a lower aminophospholipid transport rate. These data favor the relationship between aminophospholipid translocase activity and phospholipid transmembrane asymmetry. Sickle cell disease is the first case of aminophospholipid translocase pathology.
Interaction of two different disorders in the beta-globin gene cluster associated with an increased hemoglobin F production: a novel deletion type of (G) gamma + ((A) gamma delta beta)(0)-thalassemia and a delta(0)-hereditary persistence of fetal hemoglobin determinant
Authors: Losekoot M , Fodde R , Gerritsen EJ , van de Kuit I , Schreuder A , Giordano PC , Vossen JM , Bernini LF 
Published: October 2019

Abstract
We report two different disorders of the beta-globin gene cluster segregating in a Belgian family: a novel deletion that results in (G) gamma + ((A) gamma delta beta)(0)-thalassemia (thal) and a heterocellular hereditary persistence of foetal hemoglobin of the Swiss type linked to a delta(0)-thal gene (delta (0)-HPFH). Heterozygosity for the heterocellular HPFH brings about a moderate (3.4% to 8.24%) increase of hemoglobin (Hb) F having a G gamma/A gamma ratio of 4:1, whereas carriers of the G gamma + ((A) gamma delta beta)(0)-thal deletion show in their peripheral blood a considerably higher (15%) percentage of Hb F. Both defects interact in the compound heterozygotes for G gamma + ((A) gamma delta beta)(0)-thal and delta(0)-HPFH producing a further increase (up to 24%) of fetal Hb consisting entirely of G gamma chains. Molecular characterization of the (G) gamma + ((A) gamma delta beta)(0)-thal by means of Southern analysis showed that the deletion spans about 50 kb, removing the 3′ end of the A gamma- gene, the psi beta-, delta-, and beta-genes. A number of possible mechanisms leading to the overproduction of Hb F in HPFH and (G) gamma + ((A) gamma delta beta)(0)-thal will be discussed.
Detection of residual leukemia after bone marrow transplant for chronic myeloid leukemia: role of polymerase chain reaction in predicting relapse
Authors: Hughes TP , Morgan GJ , Martiat P , Goldman JM 
Published: October 2019

Abstract
We used the polymerase chain reaction (PCR) to detect residual leukemia- specific mRNA in blood and marrow from 37 patients in complete hematologic and cytogenetic remission after allogeneic bone marrow transplant (BMT) for chronic myeloid leukemia (CML). Our two-step PCR method involved the use of “nested primers” in the second step and could detect one K562 cell diluted into 10(5) normal cells. Elaborate measures were taken to exclude false-positive and false-negative results. In nine patients whose blood and marrow were studied simultaneously the results were concordant (two positive and seven negative). Twenty-three patients transplanted in chronic phase (CP) with unmanipulated donor marrow were studied. Blood cells from nine of these patients were studied 3 to 6 months post-BMT and six were PCR positive; three were negative on subsequent studies. Blood cells from 18 patients studied between 8 months and 8 years post-BMT were all PCR negative. Nine patients transplanted in CP with T-cell-depleted marrow cells were studied. Blood from five was positive 3 to 24 months post- BMT; blood from five was negative 3 to 6 years post-BMT. Four patients no longer in first CP were studied after BMT with unmanipulated donor marrow. Blood from all four was positive 5 to 19 months post-BMT. Based on the known clinical results of transplant in these three cohorts we conclude that PCR may be positive within 6 months of BMT in patients who can expect long-lasting remission, whereas PCR positivity later after BMT may indicate that the probability of cure is reduced. Thus, the technique may prove useful for early assessment of new transplant protocols that might inadvertently increase the risk of relapse.
Vesiculation of platelets during in vitro aging
Authors: Bode AP , Orton SM , Frye MJ , Udis BJ 
Published: October 2019

Abstract
Membranous microparticles (MP) appearing in the supernatant plasma of stored platelet concentrates (PC) were analyzed by flow cytometry. Two populations of MP were arbitrarily delineated by light scatter as larger or smaller than 0.5 micron fluorescent beads. An estimate of MP concentration was obtained by adding a known amount of fluorescent beads to each sample before analysis of a set number of counts on the flow cytometer. The addition of platelet activation inhibitors (prostaglandin E-1, theophylline, and aprotinin) to the anticoagulant during preparation of PC combined with a reduction in surface area of the storage container caused approximately a 40% reduction in the number of MP appearing during storage relative to donor-matched controls. In addition, the inhibited concentrates had 84% less platelet factor 3 (PF3) activity in the supernatant and 61% less released lactic dehydrogenase. A reduction in surface area of the container in the controls partially offset these differences. A significant correlation was found (rs = .748) between PF3 levels and the concentration of larger MP. The inhibitors did not reduce the small number of MP found in stored platelet-poor plasma. Surface antigen analysis showed that the majority of MP in PC were platelet-derived; most were positive for glycoprotein (GP) IIbIIIa (73%) and/or for GPIb (43% to 46%). We conclude that procoagulant MP are released from platelets during storage as a result of platelet activation augmented by interaction of platelets with the bag wall.
Platelets stimulate endothelial cells to synthesize type 1 plasminogen activator inhibitor. Evaluation of the role of transforming growth factor beta
Authors: Slivka SR , Loskutoff DJ 
Published: October 2019

Abstract
A model system consisting of thrombin-stimulated bovine platelet releasates (PRthr) and bovine aortic endothelial cells (BAEs) was developed to determine if the interaction between platelets and endothelial cells regulates fibrinolysis. Zymographic analysis indicated that PRthr treatment of BAEs decreases urokinase and increases type 1 plasminogen activator inhibitor (PAI-1) activity. Although PRthr did not affect the overall rate of BAE protein synthesis, it increased PAI-1 biosynthesis within 6 hours. This increase was complete by 12 hours, with maximum stimulation at 10 to 15 micrograms/mL PRthr (1 microgram approximately 10(7) platelets). Neutralizing antibodies to transforming growth factor beta (TGF beta) reduced this effect by 75%. Treatments that activate latent TGF beta (eg, acidification or plasmin) increased this effect approximately fivefold, suggesting that TGF beta in PRthr exists in both a latent (approximately 80%) and an active (approximately 20%) form. In contrast to PRthr, adenosine diphosphate-prepared platelet releasates did not increase PAI-1 synthesis before acidification, indicating that they contain only the latent form of TGF beta. These results suggest that platelets can modulate the fibrinolytic system of the endothelium through the release of TGF beta, and that the mechanism by which the platelets are activated can influence the relative amount of active TGF beta.
Expression of the c-myc protein is down-regulated at the terminal stages during in vitro differentiation of B-type chronic lymphocytic leukemia cells
Authors: Larsson LG , Schena M , Carlsson M , Sallstrom J , Nilsson K 
Published: October 2019

Abstract
The translocated c-myc oncogene in Burkitt's lymphoma (BL) and murine plasmacytoma (MPC) has been proposed to be expressed at a stage of differentiation at which the gene is normally silent, resulting in a continuous proliferation and an inhibited terminal differentiation. To determine whether c-myc is differently expressed at the various stages of the differentiation pathway, we used B-type chronic lymphocytic leukemia (B-CLL) cells, representing resting B lymphocytes, inducible to proliferation and/or differentiation in vitro. The c-myc protein, and Ig lambda-light chain and PCA-1 antigen as markers of B-cell maturation, were analyzed in single, morphologically defined cells by immunocytochemical double-staining. The proliferation of individual cells was determined by 3H-thymidine incorporation and by analysis of Ki-67 antigen expression. The results show that the level of c-myc expression correlates to the stage of differentiation and to the proliferative activity. Uninduced resting cells did not express c-myc. The c-myc protein was observed in the highest amount at the proliferative B-lymphoblast stage of maturation and was reduced in plasmablasts and undetectable in plasma cells. The results suggest that maturation of B cells into nonproliferative, terminally differentiated plasma cells is associated with a downregulated c-myc expression and thus support the view that the deregulated c-myc gene in BL and MPC is expressed at an inappropriate stage of maturation and thereby inhibits terminal differentiation.
Treatment of aplastic anemia in children with recombinant human granulocyte colony-stimulating factor
Authors: Kojima S , Fukuda M , Miyajima Y , Matsuyama T , Horibe K 
Published: October 2019

Abstract
Twenty children (aged 1 to 17 years) with severe or moderate aplastic anemia were treated with recombinant human granulocyte colony- stimulating factor (rhG-CSF) at a dose of 400 micrograms/m2 per day administered as a 30-minute intravenous (IV) infusion daily for 2 weeks. This treatment increased the neutrophil counts (2.7- to 28.0- fold) in 12 of the 20 patients. Increasing doses (800 or 1,200 micrograms/m2 per day) were administered to five patients who had not responded to the initial dose, and three showed an increase in neutrophil count. Differential counts of bone marrow (BM) aspirates showed an increase in the myeloid/erythroid ratio. The response was transient, however, and the neutrophil count returned to baseline within 2 to 10 days of discontinuing treatment. No severe toxicity attributable to rhG-CSF was observed. The results suggest that this agent is effective in stimulating granulopoiesis in children with aplastic anemia. Our study also indicates that rhG-CSF will be particularly useful in managing patients with aplastic anemia complicated by bacterial or fungal infection.
Temperature dependence of plasmin-induced activation or inhibition of human platelets
Authors: Lu H , Soria C , Cramer EM , Soria J , Maclouf J , Perrot JY , Li H , Commin PL , Schumann F , Regnier O 
Published: October 2019

Abstract
It is known that at 37 degrees C plasmin may have two opposite effects on platelets: at high concentrations (greater than 1.5 caseinolytic units [CU]/mL), plasmin activates platelets; at lower concentrations (0.1 to 1.0 CU/mL) it inhibits platelet activation induced by thrombin, collagen, or calcium ionophore A23187. In this study, we report that when lowering the incubation temperature to 22 degrees C, plasmin at low concentrations (0.1 to 0.5 CU/mL) fully activated platelets. When platelets were treated with 0.2 CU/mL of plasmin, lowering the incubation temperature from 37 degrees C to 22 degrees C resulted in an increase in the expression of fibrinogen receptors, in platelet release and aggregation. Thromboxane A2 was not generated by plasmin treatment at either temperature. Ultrastructural studies showed that platelets responded to low-dose plasmin at 37 degrees C by forming pseudopods, centralizing granules without fibrinogen release, whereas at 22 degrees C the same dose of plasmin caused platelet degranulation with the appearance of alpha-granule fibrinogen within the lumen of the surface connected canalicular system. In addition, at 22 degrees C plasmin at doses insufficient to induce platelet aggregation potentiated platelet response to thrombin. Thus, we suggest that plasmin may initiate both activating and inhibitory processes within platelets and that the change of temperature could influence this balance. These results may be of clinical relevance, because the fibrinolytic system was found activated during cardiopulmonary bypass in which the temperature of patient's blood circulation was reduced. This temperature-dependent behavior is also an interesting model for a further study on platelet response to serine proteinases.
Serum hepatitis C virus sequences in posttransfusion non-A, non-B hepatitis
Authors: Shibata M , Morishima T , Kudo T , Maki T , Maki S , Nagai Y 
Published: October 2019

Abstract
We investigated 17 patients (12 males and 5 females, ages 2 to 57 years old) with posttransfusion non-A, non-B hepatitis to determine relationships between clinical courses and hepatitis C virus (HCV) markers. The patients were grouped according to time course of abnormal serum alanine aminotransferase (ALT) levels into three categories (chronic biochemical disease, biochemically resolved chronic disease, and acute disease). Latest serum samples (1.3 to 10.8 years after blood transfusion) were used to detect antibodies against C100–3 antigen (anti-HCV) by enzyme-linked immunosorbent assay and HCV sequences by polymerase chain reaction (PCR) assay. Of the 17 patients, 13 patients (76.5%) were anti-HCV positive and 8 patients (47.1%), including one anti-HCV negative case, were positive for HCV RNA. In total, 14 patients (82.4%) were positive for either HCV markers. With respect to clinical course, HCV RNA was detected in six of eight patients (75%) with chronic biochemical disease, and in two of five patients (40%) with biochemically resolved chronic disease. HCV RNA was not detectable in convalescent sera from four patients with acute disease. These results show that there is a relationship between clinical status and HCV viremia, but that normal liver function tests do not always represent the clearance of the virus. Viremia in two patients with normal ALT level suggests that hepatitis is not only caused by viral cytopathic effects, but also by immunologic reactions against virus- infected cells. Thus, PCR is useful in determining the persistence of HCV infection as well as to diagnose anti-HCV negative HCV infection.
In vivo effect of human granulocyte-macrophage colony-stimulating factor on megakaryocytopoiesis
Authors: Aglietta M , Monzeglio C , Sanavio F , Apra F , Morelli S , Stacchini A , Piacibello W , Bussolino F , Bagnara G , Zauli G 
Published: October 2019

Abstract
The effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) on megakaryocytopoiesis and platelet production was investigated in patients with normal hematopoiesis. Three findings indicated that GM- CSF plays a role in megakaryocytopoiesis. During treatment with GM-CSF (recombinant mammalian, glycosylated; Sandoz/Schering-Plough, 5.5 micrograms protein/kg/d, subcutaneously for 3 days) the percentage of megakaryocyte progenitors (megakaryocyte colony forming unit [CFU-Mk]) in S phase (evaluated by the suicide technique with high 3H-Tdr doses) increased from 31% +/- 16% to 88% +/- 11%; and the maturation profile of megakaryocytes was modified, with a relative increase in more immature stage I-III forms. Moreover, by autoradiography (after incubation of marrow cells with 125I-labeled GM-CSF) specific GM-CSF receptors were detectable on megakaryocytes. Nevertheless, the proliferative stimulus induced on the progenitors was not accompanied by enhanced platelet production (by contrast with the marked granulomonocytosis). It may be suggested that other cytokines are involved in the regulation of the intermediate and terminal stages of megakaryocytopoiesis in vivo and that their intervention is an essential prerequisite to turn the GM-CSF-induced proliferative stimulus into enhanced platelet production.
Evidence for the location of the receptor-binding site of human erythropoietin at the carboxyl-terminal domain
Authors: Fibi MR , Stuber W , Hintz-Obertreis P , Luben G , Krumwieh D , Siebold B , Zettlmeissl G , Kupper HA 
Published: October 2019

Abstract
Five different peptides (P1: 84′95; P2: 152′166; P3: 52′63; P4: 7′23; P5: 110′123) homologous to relatively hydrophilic regions of human erythropoietin (huEpo) have been synthesized to identify biologically active domains of the hormone. All peptides were able to induce high titers of peptide-specific antibodies in rabbits. Antisera from rabbits induced by recombinant huEpo (rhuEpo) contained a relatively high amount of antibodies preferentially directed against three peptides (P2, P4, and P5), of which P4 comprised the amino-terminal region, P2 the carboxyl-terminus, and P5 an interior region previously described as the receptor-binding site. The same three peptides were able to induce rhuEpo-specific antibodies, whereas P1 and P3 lacked this activity. Only peptide-P2-induced antisera inhibited the biologic activity of rhuEpo in a cell proliferation assay, indicating that the carboxyl-terminal region of the molecule is essentially involved in the biologic function of rhuEpo.
Induction of transforming growth factor-beta 1 (TGF-beta 1), receptor expression and TGF-beta 1 protein production in retinoic acid-treated HL-60 cells: possible TGF-beta 1-mediated autocrine inhibition
Authors: Falk LA , De Benedetti F , Lohrey N , Birchenall-Roberts MC , Ellingsworth LW , Faltynek CR , Ruscetti FW 
Published: October 2019

Abstract
Treatment of HL-60 cells, a human promyelocytic leukemia cell line, with the vitamin A derivative retinoic acid (RA) for 7 days resulted in a dose-dependent decrease in proliferation and increase in granulocytic differentiation. The role of transforming growth factor-beta 1 (TGF- beta 1), a protein with pleiotropic effects on the proliferation and differentiation of various cell types, was examined during RA-induced differentiation of HL-60 cells. Although TGF-beta 1 alone had little effect on proliferation or differentiation of HL-60 cells, addition of TGF-beta 1 to HL-60 cells treated with a suboptimum concentration of RA (1.0 nmol/L) resulted in a marked decrease in proliferation with no effect on granulocytic differentiation. Studies of the mechanism of RA- induced TGF-beta sensitivity showed that although untreated HL-60 cells expressed low levels of TGF-beta 1 binding proteins on the cell surface, the levels were increased in a dose-dependent manner after RA treatment. Maximum induction was achieved after treatment with 10 nmol/L RA and consisted predominantly of the 65-Kd TGF-beta 1 receptor type. Moreover, RA treatment also resulted in a dose-dependent increase in both TGF-beta 1 steady-state mRNA expression and production of active TGF-beta with maximum induction at 10 nmol/LRA. RA treatment of HL-60 cells had no effect on TGF-beta 2 and TGF-beta 3 mRNA expression. These data suggest that the effects of RA may be mediated by a TGF-beta 1-mediated autocrine antiproliferative loop during differentiation of HL-60 cells.