bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemoglobin Koln: direct analysis of the gene mutation by synthetic DNA probes
Authors: Horst J , Oehme R , Kohne E 
Published: October 2019

Abstract
The molecular defect leading to Hb Koln has been analyzed by synthetic oligonucleotides. Thus, DNA of 19 nucleotides, in length corresponding to the normal and mutant beta-globin gene sequences, were used to develop a direct assay for the beta k-gene that codes for this most common form of the unstable hemoglobins. The use of synthetic oligonucleotides established that the Hb Koln mutation is due to a G-to- A transition. The conditions described here should result in the determination of all Hb Koln genotypes with a high level of confidence.
Autocrine secretion of GM-CSF in acute myeloblastic leukemia
Authors: Young DC , Griffin JD 
Published: October 2019

Abstract
Three cases of acute myeloblastic leukemia (AML) were identified in which clonogenic cells proliferated autonomously in vitro. Cells from two of these cases were found to secrete a colony-stimulating factor (CSF) that was immunologically and molecularly related to GM-CSF. Growth of AML-CFU could be blocked by the addition of a neutralizing antiserum to GM-CSF. Northern blot hybridization of leukemic cell mRNA with a cDNA probe for the GM-CSF gene revealed a 1-kb message identical in size to the normal GM-CSF message in stimulated T cells. No GM-CSF message was detected in the third case. These results indicate that constitutive expression of the GM-CSF gene, apparently by leukemic cells, can result in autonomous in vitro proliferation of AML-CFU in some cases of AML.
Lysis of human fibroblast colony-forming cells and endothelial cells by monoclonal antibody (6-19) and complement
Authors: Abboud CN , Duerst RE , Frantz CN , Ryan DH , Liesveld JL , Brennan JK 
Published: October 2019

Abstract
The murine IgG2a monoclonal antibody 6–19 binds to a wide variety of nonhematopoietic cells including human marrow-derived stromal cells but does not bind to marrow or peripheral blood cells. We studied the effects of this antibody and rabbit complement on marrow cells. Fibroblast colonies were eliminated from light density marrow cells by a single incubation with monoclonal antibody 6–19 and complement. The growth and composition of granulocytic and erythroid colonies were unaffected. Specific complement mediated cytotoxicity of the antibody was confirmed on passaged human fibroblasts derived from marrow (more than 99.6% of fibroblasts are killed by a single treatment). Similar results were obtained with human umbilical cord endothelial cells. In addition, such treatment abolished the initiation of Dexter culture stroma. Incubation of bone marrow cell suspensions with this antibody and complement will allow the study of stroma-free marrow cells in long- term liquid cultures.
Sl/Sld mouse bone marrow stroma in vitro contains an active radiation- sensitive inhibitor of normal hemopoiesis
Authors: Zuckerman KS , Prince CW , Ribadeneira M 
Published: October 2019

Abstract
Sl/Sld mice have a defective hemopoietic microenvironment. It has been assumed, based upon previous studies, that the primary abnormality in these mice is simply lack of a necessary supportive or inductive material within the hemopoietic stroma. We used in vitro long-term bone marrow cultures to characterize further the nature of the hemopoietic microenvironmental defect in Sl/Sld mice. Sl/Sld mouse bone marrow cells consistently produced less than 10% of the total hemopoietic cells and multipotent and unipotent hemopoietic progenitor cells produced in cultures of marrow from normal, congenic +/+ mice. If fresh Sl/Sld and +/+ marrow cells were mixed prior to establishing long-term marrow cultures, there was a direct correlation between number of Sl/Sld cells added and degree of inhibition of +/+ hemopoiesis. A pre- established, confluent Sl/Sld adherent stromal layer inhibited hemopoiesis by fresh +/+ marrow cells by nearly 70%, as compared with dishes with irradiated +/+ or no stroma. This inhibitory effect was abrogated by irradiation of the Sl/Sld stroma prior to addition of the fresh +/+ marrow cells. Similarly, unirradiated, but not 9 to 200 Gy irradiated Sl/Sld stroma inhibited proliferation of the factor- dependent FDC-P1 hemopoietic progenitor cell line. Thus, the Sl/Sld hemopoietic microenvironment actively inhibits hemopoiesis in vitro, and this inhibition can be at least partially eliminated by irradiation of the Sl/Sld stroma.
Mechanism of protein C-dependent clot lysis: role of plasminogen activator inhibitor
Authors: Sakata Y , Loskutoff DJ , Gladson CL , Hekman CM , Griffin JH 
Published: October 2019

Abstract
The mechanism by which activated protein C stimulates fibrinolysis was studied in a simple radiolabeled clot lysis assay system containing purified tissue-type plasminogen activator, bovine endothelial plasminogen activator inhibitor (PAI), plasminogen, 125I-fibrinogen and thrombin. Fibrinolysis was greatly enhanced by the addition of purified bovine activated protein C; however, in the absence of PAI, activated protein C did not stimulate clot lysis, thus implicating this inhibitor in the mechanism. In clot lysis assay systems containing washed human platelets as a source of PAI, bovine-activated protein C-dependent fibrinolysis was associated with a marked decrease in PAI activity as detected using reverse fibrin autography. Bovine-activated protein C also decreased PAI activity of whole blood and of serum. In contrast to the bovine molecule, human-activated protein C was much less profibrinolytic in these clot lysis assay systems and much less potent in causing the neutralization of PAI. This species specificity of activated protein C in clot lysis assays reflect the known in vivo profibrinolytic species specificity. When purified bovine-activated protein C was mixed with purified PAI, complex formation was demonstrated using immunoblotting techniques after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. These observations suggest that a major mechanism for bovine protein C- dependent fibrinolysis in in vitro clot lysis assays involves a direct neutralization of PAI by activated protein C.
T lymphocyte-derived differentiation-inducing factor inhibits proliferation of leukemic and normal hemopoietic cells
Authors: Gullberg U , Nilsson E , Sarngadharan MG , Olsson I 
Published: October 2019

Abstract
A differentiation-inducing factor (DIF) for the promyelocytic HL-60 cell line is constitutively produced by the malignant T lymphocyte line HUT-102. DIF was highly purified from HUT-102-conditioned media by means of diethylaminoethanol (DEAE)-chromatography, gel chromatography, and high-resolution, ion-exchange chromatography on a MonoQ column and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In addition to inducing differentiation of wild-type HL-60 cells, resulting in secondary inhibition of growth, DIF, at a tenfold lower concentration, inhibited the growth of some clones of the monoblastic U- 937 cell line as well as that of subclones of HL-60. The latter effect was most likely a primary growth inhibition and not secondary to differentiation; 50% inhibition of clonogenic growth in agar was seen at approximately 1.0 pmol/L of DIF. In addition, the clonogenic growth of fresh leukemia cells from 10 of 12 patients with acute myeloid leukemia (AML) was inhibited with 50% inhibition at approximately 10 pmol/L of DIF. The growth of normal granulocyte-macrophage colonies was inhibited at a similar concentration, whereas early erythroid colonies were much more resistant. DIF and interferon-gamma (gamma-IFN) were shown to be separate molecules inasmuch as a neutralizing antibody for gamma-IFN did not abolish the DIF effect. The differentiation effect on wild-type HL-60 and the proliferation inhibitory effect on leukemic and normal myeloid cells cochromatographed through all purification steps suggest that both activities are exhibited by identical polypeptides. DIF may have a role in regulating normal hemopoiesis. The growth inhibitory effect of DIF and the ability to induce differentiation of some leukemia cells may suggest a clinical utility in the treatment of leukemia.
Decreased incidence of marrow graft rejection in patients with severe aplastic anemia: changing impact of risk factors
Authors: Deeg HJ , Self S , Storb R , Doney K , Appelbaum FR , Witherspoon RP , Sullivan KM , Sheehan K , Sanders J , Mickelson E 
Published: October 2019

Abstract
Patients with severe aplastic anemia were conditioned with cyclophosphamide (200 mg/kg) and given marrow grafts from HLA-identical family members. Among 233 patients transplanted, 225 survived greater than or equal to 14 days and could be evaluated for engraftment. Forty- four of the 225 rejected their graft; 33 of these died and 11 survive. One hundred eighty-one patients had sustained engraftment; of these, 46 died and 135 survived. Binary logistic regression analyses revealed five risk factors for graft rejection: year of transplant, a large number of platelet transfusions, a positive relative response in mixed leukocyte culture, a low marrow cell dose, and omission of donor buffy coat cell infusion for transfused patients. These data show that patients transplanted recently had a lower likelihood of graft rejection than did patients transplanted in earlier years. Conceivably, this was related to changes in transfusion practices, but other factors as yet unidentified are likely to be involved. The data confirm that the largest possible number of marrow cells should be transplanted. Although the difference in the incidence of graft rejection between untransfused and transfused patients was not significant, it should be noted that transfused patients were given buffy coat cells. Because the addition of buffy coat cells results in a higher incidence of chronic graft-v-host disease (GVHD), it is still desirable to transplant patients with marrow alone early in their course before they have been transfused.
bcr rearrangement and translocation of the c-abl oncogene in Philadelphia positive acute lymphoblastic leukemia
Authors: De Klein A , Hagemeijer A , Bartram CR , Houwen R , Hoefsloot L , Carbonell F , Chan L , Barnett M , Greaves M , Kleihauer E 
Published: October 2019

Abstract
The Philadelphia (Ph1) chromosome, the cytogenetic hallmark of chronic myeloid leukemia (CML), has also been detected in a significant number of acute lymphoblastic leukemias (ALL). Using in situ hybridization, we demonstrate that in accordance with observations in CML the Ph1 chromosome in ALL patients is the result of a consistent translocation of the c-abl oncogene to the Ph1 chromosome. Southern blot analysis using bcr probes, however, suggests that Ph1-positive ALL includes heterogeneous leukemic subtypes: six ALL patients showed bcr rearrangements as observed in CML; in three other patients recombination involving 5′ bcr sequences could be demonstrated, but the corresponding translocated 3′ bcr sequences were not detectable. A third group of five patients did not show any bcr rearrangements at all. Northern blot analysis using RNA from three Ph1-positive ALL patients revealed that in the leukemic cells of two patients larger c- abl mRNA transcripts were present, as in CML. In the RNA of one patient without a detectable bcr rearrangement, only the normal c-abl mRNA transcripts are present. The observed heterogeneity in bcr rearrangements of this group of Ph1-positive ALL patients is in contrast with the consistent results obtained in more than 50 Ph1- positive CML patients investigated in chronic and acute states.
Substance P receptors in rat spleen: characterization and autoradiographic distribution
Authors: Wiedermann CJ , Sertl K , Pert CB 
Published: October 2019

Abstract
The interaction of substance P with intact lymphatic tissue was quantified and autoradiographically visualized, using slide-mounted tissue sections of rat spleen. Radiolabeled substance P binds rapidly to an apparently single class of noninteracting high affinity sites (Kd = 2.4 nmol/L; Bmax = 9.4 fmol/mg protein). The ligand selectivity pattern suggests that substance P binding sites are similar to substance P receptors found in other tissues, including the brain, T lymphocytes, and macrophages. Substance P receptors are highly concentrated in the antigen-trapping spleen marginal zone, with low densities being found in the red pulp. No specific binding of radiolabel to T cell-dependent immunologic domains of the spleen is seen. The distribution of substance P receptors suggests that substance P is probably involved in the control of sensory functions of the immune system.
Hydroxyurea-induced augmentation of fetal hemoglobin production in patients with sickle cell anemia
Authors: Charache S , Dover GJ , Moyer MA , Moore JW 
Published: October 2019

Abstract
Five patients with sickle cell anemia were treated with hydroxyurea (HU), in hopes of augmenting their production of fetal hemoglobin. Laboratory responses in two patients treated for more than 2 years were encouraging and there were suggestions of clinical improvement. Long- term HU therapy should be considered for severely affected adults with sickle cell anemia who are willing to accept what is probably a small risk of carcinogenesis. Preliminary chromosomal analysis and knowledge of the clastogenic properties of HU suggest that conception and pregnancy should be avoided. Pharmacokinetic studies will probably be necessary to adjust individual dosage schedules so that cytotoxicity is avoided. F cell responses can be seen in 2 to 3 weeks if the HU dose is optimal, but establishment of a large number of F cells in the circulation may take a month or longer.
Lithium augments GM-CSA generation in canine cyclic hematopoiesis
Authors: Hammond WP , Rodger ER , Dale DC 
Published: October 2019

Abstract
Cyclic hematopoiesis in gray collie dogs can be cured by lithium treatment. We examined the mechanism of lithium's effect by developing an assay for the canine equivalent of GM-CSF (called GM-CSA). Phytohemagglutinin (PHA)-stimulated canine blood mononuclear cells produce GM-CSA in a dose-dependent manner; this GM-CSA stimulates more neutrophil-containing colonies than does endotoxin-treated dog serum. Production of GM-CSA by PHA-stimulated normal dog cells was not altered by lithium. However, cells from gray collies during their neutrophilic period increased their GM-CSA when lithium (2 mEq/L) was added to low doses of PHA, whereas neutropenic gray collie cells did not. These data suggest that lithium could modulate cyclic hematopoiesis by increasing intramedullary GM-CSA at the time when marrow neutrophilic progenitor cells are at their nadir.
Different stimulative effects of human bone marrow and fetal liver stromal cells on erythropoiesis in long-term culture
Authors: Slaper-Cortenbach I , Ploemacher R , Lowenberg B 
Published: October 2019

Abstract
The factors determining the predominantly erythroid direction of human fetal liver hematopoiesis are unknown. We compared the capacities of human fetal liver and bone marrow stromas to sustain fetal and adult hematopoiesis in long-term cultures. In various marrow-fetal liver combinations of stroma and recharge, the maintenance of erythroid (BFU- e) and myeloid (CFU-GM) precursors in the nonadherent phase was determined. The morphology of the fetal liver nucleated cells during culture was also examined. This study shows that fetal liver stromas efficiently support fetal BFU-e for 6 to 7 weeks in vitro. Bone marrow stromas were not able to maintain fetal BFU-e beyond 4 weeks. Significant numbers of marrow BFU-e were not sustained in vitro on either source of stroma. On the other hand, the stroma layers of fetal liver and marrow origin were equally effective in maintaining fetal CFU- GM and adult CFU-GM in long-term culture. These findings show that the human embryonic liver stroma is a preferential site for stimulating fetal erythropoiesis. They do not demonstrate differences in stroma function to explain the relative paucity of myelopoiesis in the fetal liver.
Association of red cell spherocytosis with deletion of the short arm of chromosome 8
Authors: Chilcote RR , Le Beau MM , Dampier C , Pergament E , Verlinsky Y , Mohandas N , Frischer H , Rowley JD 
Published: October 2019

Abstract
Congenital spherocytic anemia is a common disorder, but in most cases the nature of the underlying membrane lesion is unknown and the genetic defect has not yet been unequivocally mapped to a chromosome. We studied two dysmorphic siblings with neurologic findings and hemolytic anemia. Clinical and laboratory findings in these two siblings were consistent with the diagnosis of congenital spherocytosis whereas both parents and two unaffected siblings were normal. The two affected children had an abnormal chromosomal complement as a result of a deletion of the short arm of chromosome 8 [(46,XX,del(8)(p11.1p21.1)]. These results suggest that a gene whose deletion results in a congenital spherocytic anemia phenotype resides on this region on the short arm of chromosome 8.
Interaction of ristocetin and bovine plasma with guinea pig megakaryocytes: a means to enrich megakaryocytes based on membrane rather than physical characteristics
Authors: Jackson CW , Steward SA , Hutson NK , Ashmun RA 
Published: October 2019

Abstract
We have investigated whether megakaryocytes can be aggregated by ristocetin and bovine plasma and whether such aggregation can be used as a step in the purification of megakaryocytes from marrow cell suspensions. Guinea pig marrow cell suspensions were first enriched for megakaryocytes by density equilibrium centrifugation in continuous Percoll density gradients. The megakaryocyte-enriched marrow was stirred in a platelet aggregometer to which ristocetin or bovine plasma was added. Megakaryocytes were aggregated by both ristocetin and bovine plasma with the proportion aggregated being related to the concentration of ristocetin or bovine plasma. Maximal aggregation (greater than 90% of megakaryocytes) was achieved with 2.0 mg/mL ristocetin or 5% bovine plasma and required five minutes. All maturation stages of morphologically recognizable megakaryocytes were aggregated. The megakaryocyte aggregates were separated from the marrow suspension by sedimentation at 1 g and the megakaryocytes disaggregated by dilution with media (ristocetin aggregated) or addition of dextran sulfate (bovine plasma aggregated). Megakaryocyte purity and recovery were higher with bovine plasma than with ristocetin. A mean of 92% of the megakaryocytes in the bovine plasma aggregated cell suspensions were recovered with megakaryocytes constituting an average of 76% of the final cell suspensions. The viability as well as the diameters and DNA content distribution of these megakaryocytes were similar to those of the starting population. We conclude that guinea pig megakaryocytes behave like platelets in that they can be aggregated with ristocetin or bovine plasma and that megakaryocyte aggregation induced by ristocetin or bovine plasma provides a means to enrich these cells based on membrane rather than physical characteristics. This approach yields purified megakaryocyte populations that are representative of those in unfractionated marrow.
Human GM-CSF primes neutrophils for enhanced oxidative metabolism in response to the major physiological chemoattractants
Authors: Weisbart RH , Kwan L , Golde DW , Gasson JC 
Published: October 2019

Abstract
Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a T cell- derived lymphokine which induces hematopoietic precursor cells to proliferate in vitro and differentiate to neutrophils and macrophages. GM-CSF also inhibits the motility of mature neutrophils (NIF-T activity), and primes neutrophils to enhance oxidative metabolism in response to the bacterial chemoattractant, N-formyl-methionyl-leucyl- phenylalanine (f-MLP). The present study was designed to determine whether this lymphokine also enhances neutrophil oxidative metabolism in response to the other major physiological chemoattractants which include complement-derived C5a, and the 5-lipoxygenation product of arachidonic acid, leukotriene B4 (LTB4). Superoxide anion production was measured as superoxide dismutase-inhibitable cytochrome C reduction. Purified biosynthetic GM-CSF enhanced superoxide anion production by neutrophils in response to f-MLP, C5a desArg, and LTB4. In contrast to several other factors which prime neutrophils, GM-CSF did not prime for an enhanced oxidative response to phorbol myristate acetate (PMA). These results suggest that GM-CSF may be an endogenous regulator of neutrophil inflammatory responses induced by the major physiological chemoattractants.
Inhibition of thromboxane formation in vivo and ex vivo: implications for therapy with platelet inhibitory drugs
Authors: Reilly IA , FitzGerald GA 
Published: October 2019

Abstract
The capacity of platelets to generate thromboxane A2, reflected by measurement of serum thromboxane B2 (TxB2), greatly exceeds the systemic production of thromboxane in vivo. Thus, it is possible that substantial but incomplete inhibition of thromboxane formation ex vivo would still allow marked augmentation of thromboxane production in vivo. To address this hypothesis, we administered aspirin 120 mg, a selective inhibitor of thromboxane synthase (TxSl), 3-(1H-imidazol-1-yl- methyl)-2-methyl-1H-indole-1-propanoic acid (UK-38, 485) 200 mg, and a combination of both drugs to 12 healthy volunteers and measured the effects on serum TxB2 and urinary 2,3-dinor-thromboxane B2 (Tx-M), an index of endogenous thromboxane biosynthesis. Although serum TxB2 was maximally inhibited by 94 +/- 1% after aspirin and 96 +/- 2% after the TxSl, maximal depression of Tx-M was only 28 +/- 8% and 37 +/- 9%, respectively. Combination of aspirin with the TxSl resulted in a small but significant increase in inhibition of thromboxane generation ex vivo (98 +/- 1% v 94 +/- 1%; P less than 0.05), but a disproportionately greater fall in thromboxane synthesis in vivo (58 +/- 7%; P less than 0.01). Consistent with further inhibition of platelet thromboxane synthesis, addition of the TxSl abolished the transient decline in prostacyclin formation after aspirin alone. Administration of a lower dose of aspirin (20 mg) to 6 healthy subjects caused a small reduction in Tx-M (12 +/- 4%; P less than 0.05) and inhibited serum TxB2 by 48 +/- 2%. The relationship between inhibition of platelet capacity to form thromboxane ex vivo (serum TxB2) and synthesis in vivo (Tx-M) departed markedly from the line of identity. When total blockade of the capacity of platelets to generate thromboxane is approached, minor decrements in capacity result in a disproportionate depression of actual thromboxane biosynthesis. These results imply that pharmacologic inhibition of serum TxB2 must be virtually complete before thromboxane- dependent platelet activation is influenced in vivo.