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  • American Society of Hematology  (39,000)
  • Blackwell Publishing Ltd  (22,840)
  • 2005-2009  (37,344)
  • 1980-1984  (24,338)
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  • 1
    Publication Date: 2017-04-04
    Description: Most of the ancient town of Tindari (NE, Sicily) was settled on a plateau the most surficial layer of which was made of unconsolidated material. Ongoing excavations at the archaeological site at Tindari uncovered a large portion of the decumanus which suffered deformations preliminarily assigned to coseismic effects. An analysis of the local dynamic response through the simulation of strong seismic shaking to the bedrock and modelling of spectral ratios of the bedrock-soft soil was carried out to verify the susceptibility of superficial terrains of the promontory to coseismic deformations. To perform this simulation the finite element method (FEM) was used. Four accelerometric recordings of three earthquakes of medium-high magnitude, recorded on rocky sites, were chosen to simulate the seismic shaking, using a constitutive law for the materials composing the promontory layers both of linear-elastic type and of elastoplastic type. The analysis of the linear-elastic field allowed the definition of the frequencies for which the spectral ratios of the accelerations recorded the highest amplifications; in particular the frequency range 31.5–37.2 Hz can be combined with deformation of the paved floor of the decumanus. The analysis in the elastoplastic field highlighted the zones of promontory more susceptible to suffer plasticization process. The results show that the topmost layer of the decumanus is the most susceptible to suffer plasticization. Therefore, the performed analysis lends greater support to the hypothesis that the deformations were produced by seismic shaking.
    Description: Published
    Description: 213-222
    Description: 3.10. Sismologia storica e archeosismologia
    Description: JCR Journal
    Description: reserved
    Keywords: Fourier analysis ; Elasticity and anelasticity ; Earthquake ground motions ; Site effects ; Computational seismology ; 04. Solid Earth::04.06. Seismology::04.06.99. General or miscellaneous ; 04. Solid Earth::04.06. Seismology::04.06.05. Historical seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 2
    Publication Date: 2017-04-04
    Description: The tectonic deformation of the Lipari-Vulcano complex, one of the most important active volcanic areas of Mediterranean region, is studied here through the analysis of ten years (1996-2006) of GPS data from both 3 permanent and 13 non-permanent stations. This area can be considered crucial for the understanding of the Eurasia-Africa plates interaction in the Mediterranean area, and, in general, this work emphasize a methodological approach, already applied in other areas worldwide (e.g. Shen et al., 1996, El-Fiki and Kato, 1999) where geodetic data and strain parameters maps of critical areas can help to improve our understanding of their geodynamical aspects. In this framework, this study is aimed at providing a kinematic deformation model on the basis of the dense geodetically estimated velocities of the Lipari-Vulcano complex. In particular, the observed deformation pattern can be described by a mix between 1) the main N-S regional compression and 2) a NNE-SSW compression with a small right-lateral strike slip component acting along a tectonic structure N°40W trending located between the two islands. This pattern was inspected through a simplified synthetic model.
    Description: This research has benefited from funding provided by the Italian Presidenza del Consiglio dei Ministri – Dipartimento della Protezione Civile (DPC).
    Description: Published
    Description: 370–377
    Description: 1.9. TTC - Rete GPS nazionale
    Description: JCR Journal
    Description: reserved
    Keywords: GPS ; Aeolian Islands ; strain ; modelling ; 04. Solid Earth::04.03. Geodesy::04.03.01. Crustal deformations
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 3
    Publication Date: 2012-02-03
    Description: We analyse P-wave traveltimes for the Mediterranean area, using both teleseismic and regional arrivals for shallow earthquakes reported in the Bulletins of the International Seismological Centre. We model delays between pairs of 0.5° × 0.5° cells, obtaining a detailed representation of the P traveltime heterogeneities. Examination of these anomalies shows the clear presence of geographically coherent patterns—consistent with known geological features—due to significant structure in the upper mantle. We present a scheme, based on an empirical heterogeneity correction (EHC) to P-wave traveltimes, to improve earthquake location. This method provides similar benefits to those of a location procedure based on ray tracing in a 3-D model, but it is simpler and computationally more efficient. The definition of the traveltime heterogeneity model, being based on a statistical procedure, bypasses most of the critical points and possible instabilities involved in model inversion. EHC relocation, applied to Mediterranean earthquakes, allows one to predict about 70 per cent of the estimated signal due to heterogeneity and produces epicentral and origin time-shifts of, respectively, 4.22 km and 0.35 s (rms). From a synthetic experiment, in which we use the proposed algorithm to retrieve known source locations, we estimate that the rms improvement achieved by the EHC relocation over a simpler, standard, 1-D location is more than 20 per cent for both epicentral mislocation and origin time-shifts.
    Description: Published
    Description: 232-254
    Description: 3.3. Geodinamica e struttura dell'interno della Terra
    Description: JCR Journal
    Description: reserved
    Keywords: earthquake location ; Mediterranean ; P waves ; traveltime ; upper mantle ; 04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 4
    Publication Date: 2017-04-04
    Description: Recent geological studies performed at Etna allow reassessing the stratigraphic frame of the volcano where distinct evolutionary phases are defined. This stratigraphic reconstruction was chronologically constrained on the basis of a limited number of U–Th and K–Ar age determinations whose uncertainty margins are sometimes too wide. For this reason, we successfully adopted at Etna the 40Ar/39Ar technique that allowed obtaining more precise age determinations. The incremental heating technique also gives information on sample homogeneity, and potential problems of trapped argon. Five samples were collected from stratigraphically well-controlled volcanic units in order to chronologically define the transition between the fissure-type volcanism of the Timpe phase to the central volcanism of the Valle del Bove Centers. Isotopic ages with an uncertainty margin of 2–4% have been obtained emphasizing that this transition occurred (130– 126 ka) without significant temporal hiatus.
    Description: University of Catania grants (COFIN- 2002, resp. F. Lentini); CNR-IDPA and INGV-Sezione di Catania grants.
    Description: Published
    Description: 292-298
    Description: 3.5. Geologia e storia dei sistemi vulcanici
    Description: JCR Journal
    Description: reserved
    Keywords: 40Ar/39Ar dating ; Etna ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 5
    Publication Date: 2017-04-04
    Description: The paper describes a case of a natural emission of methane from soil in an urban development area, generating a significant risk for the local population and buildings, due to gas explosiveness and asphyxiation potential. The site is located on the south-western margin of the East-European Platform in eastern Romania, in a hydrocarbon-prone area crossed by the Pericarpathian lineament and regional faults. Molecular composition of gas and stable isotopic analyses of methane (CH4〉90%, δ to the power of 13 C1: -49.4‰, δD1: -173.4‰) indicate a dominant thermogenic origin, with significant amounts of C2-C5 alkanes (~5%), likely migrating through faults from a deep reservoir. Possible candidates are the Saucesti and Secuieni gas fields, located in the same petroleum system. Two surface geochemical surveys, based on closed-chamber flux measurements, were performed to assess the degassing intensity and the extent of the affected area. Methane fluxes from soil reach orders of 10 to the power of 4 mg m to the power of -2 day to the power of -1. Gas seepage mainly occurs in one zone 30 000 m2 wide, and it is likely controlled by channeling along a fault and gas accumulation in permeable sediments and shallow subsoil. The estimated total CH4 emission is about 40 t year to the power of -1 CH4, of which 8–9 t year to the power of -1 are naturally released from soil and 30–35 t year to the power of -1 are emitted from shallow boreholes. These wells have likely channeled the gas accumulated in shallow alluvial sediment but gas flux from soil is still high and mitigation measures are needed to reduce the risk for humans and buildings.
    Description: Published
    Description: 311-320
    Description: 3.8. Geofisica per l'ambiente
    Description: JCR Journal
    Description: reserved
    Keywords: gas hazard ; methane seepage ; soil degassing ; thermogenic gas ; 03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 6
    Publication Date: 2017-04-04
    Description: The Chimaera gas seep, near Antalya (SW Turkey), has been continuously active for thousands of years and it is known to be the source of the first Olympic fire in the Hellenistic period. New and thorough molecular and isotopic analyses including methane (approximately 87% v/v; δ to the power of 13 C1 from -7.9‰ to -12.3‰; δ to the power of 13 D1 from -119‰ to -124‰), light alkanes (C2 + C3 + C4 + C5 = 0.5%; C6+: 0.07%; δ to the power of 13 C2 from -24.2‰ to -26.5‰; δ to the power of 13 C3 from -25.5‰ to -27‰), hydrogen (7.5–11%), carbon dioxide (0.01–0.07%; δ to the power of 13 CCO2: -15‰), helium (approximately 80 ppmv; R/Ra: 0.41) and nitrogen (2–4.9%; δ to the power of 15 N from -2‰ to -2.8‰) converge to indicate that the seep releases a mixture of organic thermogenic gas, related to mature type III kerogen occurring in Palaeozoic and Mesozoic organic-rich sedimentary rocks, and abiogenic gas produced by low-temperature serpentinization in the Tekirova ophiolitic unit. Methane is not related to mantle or magma degassing. The abiogenic fraction accounts for about half of the total gas released, which is estimated to be well beyond 50 ton year to the power of -1. Ophiolites and limestones are in contact along a tectonic dislocation leading to gas mixing and migration to the Earth’s surface. Chimaera represents the biggest emission of abiogenic methane on land discovered so far. Deep and pressurized gas accumulations are necessary to sustain the Chimaera gas flow for thousands of years and are likely to have been charged by an active inorganic source.
    Description: Published
    Description: 263-273
    Description: 3.8. Geofisica per l'ambiente
    Description: JCR Journal
    Description: reserved
    Keywords: abiogenic methane ; isotopic composition ; ophiolites ; seep ; serpentinization ; 03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 7
    Publication Date: 2017-04-04
    Description: In eastern Elba Island (Tuscany, Italy), a shallow crustal level felsic, tourmaline-bearing, dyke-sill swarm of Late Miocene age is associated with abundant tourmaline-quartz hydrothermal veins and metasomatic masses. Development of these veins and masses in the host rocks demonstrates multiple hydro-fracturing by magmatic, boron-rich saline fluid. Tourmalines in felsic dykes are schorl, whereas in veins and metasomatic masses, tourmaline composition ranges from schorl-dravite through dravite to uvite. This compositional shift is evidence for an increasing contribution to the magmatic boron-rich fluids by a Mg-Ca-Ti-rich external component represented by biotite-rich and amphibolite host rocks. This system can be envisaged as an exposed proxy of the high temperature hydrothermal system presently active in the deepest part of the Larderello-Travale geothermal field (Tuscany).
    Description: Published
    Description: 318-326
    Description: 3.3. Geodinamica e struttura dell'interno della Terra
    Description: 3.5. Geologia e storia dei sistemi vulcanici
    Description: JCR Journal
    Description: reserved
    Keywords: Hydro-fractures ; geothermal systems ; Magmatism ; southern Tuscany ; 04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 8
    Publication Date: 1984-07-01
    Description: Cases of acute leukemia showing both terminal deoxynucleotidyl transferase (TdT) and myeloperoxidase (MPO) activities are usually classified as acute myelogenous leukemia (AML). Although some reports have implied overlap of TdT and MPO based on population percentages, direct evidence for simultaneous expression of TdT and MPO by a leukemic blast is lacking. By use of a simple new technique developed in our laboratory for identifying TdT and MPO in individual cells by light microscopy, we examined three cases of acute leukemia with both TdT and MPO positivity and found that the incidence of cells positive for both TdT and MPO was 0%, 1%, and 23%. Cytogenetic analysis showed a single leukemic clone in all patients, providing additional evidence that these leukemias arose from a single cell capable of expressing both MPO and TdT. These findings have implications for understanding the relation between MPO and TdT expression in leukemia.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
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  • 9
    Publication Date: 1984-07-01
    Description: Biosynthesis and molecular structure of major histocompatibility complex (MHC) class II antigens of DR2/DR7 hairy cells were analyzed by two-dimensional polyacrylamide-gel electrophoresis (2D-PAGE). Two anti- human Ia monoclonal antibodies (mAb) were used to immunoprecipitate DR and DR-linked DC/DS molecules. Monoclonal antibody VI 15 C recognizes DR (I-E-like) molecules and CA 2.06 precipitates DR and DR-linked DC/DS (I-A-like) molecules in DR7 allotypes. Studies were performed on a pure population of hairy cells before and after culture with phorbol ester: 12-O-tetradecanoyl phorbol-13-acetate (TPA), 5 azacytidine (5 Aza), sodium butyrate (NA-BU), and phytohemagglutinin (PHA-P). Before any treatment, hairy cells expressed and synthesized DR antigens: DR alpha and beta subunits appeared both qualitatively and quantitatively normal by 2D-PAGE profile. In contrast, the hairy cells failed to express and synthesized any DC/DS molecule. The lack of DC/DS molecular expression was restored after culture in presence of TPA, sodium butyrate, and 5 azacytidine, but not after PHA-P treatment. Differential molecular expression of MHC class II antigens in leukemic cells provides a model to define further discrete stages of hemopoietic differentiation and study the role of these molecules in the cellular interactions occurring during differentiation.
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  • 10
    Publication Date: 1984-07-01
    Description: The activity of delta-aminolevulinic acid (ALA) dehydratase, an enzyme involved in heme biosynthesis, has been shown to increase in Friend virus-transformed murine erythroleukemia (MEL) cells during erythroid differentiation. In this study, the nature of the increase in ALA dehydratase activity in MEL cells was examined using a monospecific antibody directed to the enzyme. A sevenfold increase in ALA dehydratase activity was observed after cells had been treated with 1.5% Me2SO for 5 days. Ouchterlony double immunodiffusion analysis showed that lysates from untreated and Me2SO-treated MEL cells formed a single precipitin line with rabbit IgG directed to the normal mouse liver ALA dehydratase. A single arc of identity was also observed with the lysates from normal mouse erythrocytes, spleen, liver, and lysates from both uninduced and induced MEL cells. Rocket immunoelectrophoresis demonstrated that lysates from both uninduced and induced cells formed rockets with the IgG and that the peak height of the rocket was proportional to the ALA dehydratase activity applied. The slope of linear plots of rocket peak heights v ALA dehydratase activity was identical for lysates from uninduced and Me2SO-induced cells. Succinylacetone, a potent inhibitor of ALA dehydratase, was shown to markedly inhibit the activity of the enzyme, but did not interfere with the synthesis of ALA dehydratase induced by Me2SO treatment. Me2SO- induced increases in ALA dehydratase activity and the enzyme protein were both blocked by the simultaneous treatment of cells with 5-bromo- 2′-deoxyuridine (BrdU). BrdU-mediated repression of ALA dehydratase was partially overcome by treating the cells with thymidine. These data demonstrate that increased ALA dehydratase activity in MEL cells undergoing erythroid differentiation after Me2SO treatment is due to de novo synthesis of the same enzyme protein present in uninduced MEL cells as well as in normal erythrocytes. This represents the first direct demonstration of an increase in a heme biosynthetic pathway enzyme protein in erythroid cells undergoing differentiation.
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  • 11
    Publication Date: 1984-07-01
    Description: Hebbel and colleagues have proposed that increased adherence of sickle red cells to vascular endothelium may initiate vasoocclusive events in sickle cell disease. We have developed a micropipette technique to obtain direct, quantitative measure of the adherence of individual red cells to vascular endothelial cells. Using this technique, we found that the vast majority of sickle cells suspended in autologous plasma were strongly adherent to endothelial cells, whereas only a small fraction of normal cells were weakly adherent. Influence of plasma factors on adherence was determined by measuring adherence of sickle cells suspended in normal plasma and normal cells suspended in sickle plasma. Although over 90% of sickle cells adhered to endothelial cells in autologous plasma, the percentage of adherent cells decreased dramatically to less than 20% when the same sickle cells were suspended in normal plasma. In contrast, adhesion of normal red cells suspended in sickle plasma was only modestly increased compared to adhesion in autologous normal plasma. Our results provide direct evidence for markedly enhanced adherence of sickle cells to endothelial cells. In addition, they suggest that both cell membrane changes and plasma factors contribute to this interaction. The requirement for sickle plasma further implies that temporal changes in plasma factors may play an important role in determining the onset of vasoocclusive crisis.
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  • 12
    Publication Date: 1984-07-01
    Description: The effect of splenectomy on the response to random donor platelet transfusion in 15 multitransfused thrombocytopenic patients is presented. Eight patients responded poorly, with low corrected platelet count increments at 1 and 24 hours posttransfusion. These eight patients were clinically alloimmunized and had lymphocytotoxic antibody ( LCTAb ) in their sera. They responded well to closely HLA-matched transfusions. In contrast, seven splenectomized patients responded well to random donor platelets. Five of these patients had no LCTAb and no other evidence of immunization. Two patients who responded well to random donor platelets had “weak” LCTAb , and one responded to platelets presplenectomy in the presence of this antibody. Splenectomy does not improve the response to random donor platelets in alloimmunized recipients.
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  • 13
    Publication Date: 1984-08-01
    Description: Prenatal diagnosis of hematologic diseases can now be performed with fetal blood, fetal amniotic fluid cell DNA, and fetal chorionic villi DNA. Some hemoglobinopathies can be detected by all three methods, and the choice will depend on the available obstetric and laboratory techniques, as well as the time of presentation of the pregnancy. Hopefully, further development of molecular probes and techniques will soon expand these options to all of the globin disorders. Detection of coagulation disorders in utero currently requires samples of pure fetal blood. Gene cloning is accomplished for some (factor IX and antithrombin III) and is underway for others (factor VIII), and further investigation is necessary to determine whether deficiencies in these gene products are due to gene deletion or to mutant genes linked to polymorphic restriction enzyme sites of diagnostic use. Thus, molecular biology may be applied to prenatal diagnosis of the clotting problems, but this has not yet been accomplished. Disorders affecting the number and/or function of erythrocytes, leukocytes, and platelets can be diagnosed by analysis of fetal blood. Blood samples will continue to be required until more is known about the molecular biology of hematopoiesis. Syndromes that can be diagnosed by chromosome studies should be revealed in cultures of amniotic fluid cells, fetal blood lymphocytes, and chorionic villi cells. Cultured cells can be examined for karyotypes, Y-chromatin, spontaneous or induced chromosome breakage, DNA repair, SCEs, and translocations. The techniques for culturing amniotic cells and fetal blood white cells are established, and those for growing cells from chorionic villi are improving rapidly. Direct preparations of cells from villi only may suffice for some of the above analyses. The study of hematologic disease in utero has thus come full circle, from the use of amniotic cells to determine the sex in X-linked disorders, to fetal blood sampling for the analysis of gene products, then back to amniocentesis for DNA, and now earlier in gestation to chorionic villi. All of this has occurred in less than ten years, and it is anticipated that developments in the next ten years will be equally dramatic. The future should bring all prenatal testing into the first trimester, use molecular probes, and provide for both early diagnosis and early treatment of genetic hematologic disease.
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  • 14
    Publication Date: 1984-07-01
    Description: Methotrexate has been used as the mainstay therapy to prevent or ameliorate graft-versus-host disease (GVHD) in allogeneic bone marrow transplantation. We began a nonrandomized study in which methotrexate was not given routinely. Fifty-five patients underwent transplant for acute leukemia (44 patients), aplastic anemia (6 patients), and other malignancies (5 patients). Methotrexate was given to 34 patients (MTX +) and was withheld in 21 patients (MTX -). Median (range) age of patients was 12 (0.8–43) years in the MTX + group, and 16 (3–45) years in the MTX- group. Mean days (+/- SEM) to engraftment (neutrophils greater than 500/microL, and platelets greater than 20,000/microL untransfused) occurred earlier in the MTX- patients (19.6 +/- 1.4 v 24.9 +/- 1.8 days for granulocytes, and 19.3 +/- 1.5 v 27.4 +/- 2.8 days for platelets, P less than .05). There were no statistically significant differences between the patient groups for the incidence or severity of GVHD (10/34 in the MTX + group had grade O-l GVHD compared to 9/21 in the MTX- group). The interstitial pneumonitis occurred at a significantly increased rate in patients who received methotrexate (15/34) compared to those patients who did not (3/21) (P = .02). However, there was also a significant relationship between the interstitial pneumonitis and the preparative regimen: if the preparative regimen contained 1,000 rad single fraction total body irradiation, 8/14 patients were affected compared to 5/22 patients affected when 1,200 rad fractionated total body irradiation was used (P = .03). Because methotrexate significantly retards hematopoietic reconstitution, randomized trials for GVHD prevention are recommended.
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  • 15
    Publication Date: 1984-06-01
    Description: Acute graft-versus-host disease (GVHD), a major complication of allogeneic bone marrow transplantation (BMT), is probably mediated by T lymphocytes present in the marrow graft. In this study, the repopulation of the peripheral blood with T4+ and T8+ T cells was investigated during the period preceding the occurrence of acute GVHD. Twenty-four allogeneic and 11 autologous BMT recipients were monitored from day 4 post-BMT onward by the use of monoclonal antibodies, indirect immunofluorescence, and flow cytometry. The recipients of allogeneic transplants received methotrexate as GVHD prophylaxis. Similar recovery patterns for T4+ and T8+ T cells were found following autologous and allogeneic BMT. However, lymphoid repopulation occurred at a clearly faster rate after autologous BMT. T4+ T cells were the first to reappear in the peripheral blood, followed by T8+ T cells 4–7 days later. The T8+ T cell reconstitution occurred at an even faster rate in patients who were to develop grade II-IV GVHD, as compared with those with grade O-I GVHD, thus leading to an earlier decrease in the T4/T8 ratio. Of 10 patients with a T4/T8 ratio less than 2.5 at day 19, 9 developed grade II-IV GVHD and 1 showed no GVHD. Of 14 patients with a ratio greater than 2.5 at that time, only 2 developed grade II-IV and 12 grade O-I GVHD (p less than 0.001). In the 11 patients developing grade II-IV GVHD, the T4/T8 ratio decreased to values less than 2.5 before the first clinical symptoms of GVHD in 9; it coincided in one and occurred later in another patient. Thus, early monitoring of the T4/T8 ratio can distinguish patients at risk of developing grade II-IV GVHD.
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  • 16
    Publication Date: 1984-06-01
    Description: We have studied the role of factor VIII-von Willebrand factor (FVIII- vWF) in both platelet adherence to subendothelium and ristocetin- induced platelet aggregation using monoclonal antibodies to human FVIII- vWF. Twenty-five monoclonal antibodies were obtained, two of which were directed to the factor VIII moiety of FVIII-vWF; one of these two completely inhibited the procoagulant activity (FVIII:C). The remaining 23 monoclonal antibodies were directed to the von Willebrand factor moiety of FVIII-vWF. The ability of the latter monoclonal antibodies to inhibit platelet adherence to arterial subendothelium was investigated with a perfusion model. According to the number of platelets adhering to the subendothelium, three groups of monoclonal antibodies could be discerned: (A) antibodies not affecting platelet adherence; (B) antibodies that inhibited platelet adherence to the level as observed when von Willebrand's disease plasma was tested; and (C) antibodies that completely inhibited both platelet adherence to subendothelium and ristocetin-induced platelet aggregation. The two antibodies present in group C competed for the same or closely related epitope(s) present on FVIII-vWF. These results demonstrate that a domain is present on the FVIII-vWF molecule that is associated both with ristocetin-induced aggregation and with the ability of FVIII-vWF to support platelet adherence to the subendothelium. Based on these observations, it is concluded that ristocetin-induced binding of FVIII-vWF to platelets reflects, at least in part, a physiologic mechanism regulating the function of FVIII-vWF in primary hemostasis.
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  • 17
    Publication Date: 1984-07-01
    Description: We have analyzed a cloned beta O-thalassemia (beta O-thal) gene from a patient doubly heterozygous for hemoglobin Lepore and beta O- thalassemia. Studies of 3H-uridine incorporation into beta-globin mRNA in this patient's erythroblasts suggested an intranuclear defect in both beta and Lepore (delta beta) mRNA synthesis, as did S1 nuclease analysis of nuclear RNA. However, the nucleotide sequence of the beta O- thal gene revealed only a single base change in codon 39 (CAG----UAG), which created a premature translation termination codon. The 5′ flanking sequence, including transcription promotor boxes and the mRNA initiation (CAP) site, were normal. The unexpected effect of this mutation on intranuclear beta-mRNA synthesis in vivo was studied by insertion of the cloned gene into a plasmid expression vector and transfection into tissue culture (COS-1) cells. beta-Globin mRNA produced by the transfected cells was assessed by S1 nuclease analysis. The beta O-39 thalassemia gene generated five- to tenfold less beta- mRNA than a normal beta-gene in both nuclear and cytoplasmic RNA, simulating the results observed in vivo. Moreover, the small amount of beta O-39 mRNA produced was as stable as normal beta-mRNA during an actinomycin D chase, ruling out rapid cytoplasmic turnover as a cause of the reduced accumulation. Cotransfection of the beta O-39 thalassemia gene with a mutant tyrosine suppressor tRNA gene resulted in restoration of the beta O-39 mRNA accumulation to near-normal levels. On the basis of these results, we suggest that the low levels of beta-mRNA known to exist in the common form of beta O-thalassemia, beta O-39 thalassemia, result from a lesion in transcription, or early posttranscriptional processes; the defect appears to be corrected by restoration of proper translational potential to the mutant mRNA, at least in a gene transfer-expression system in tissue-culture cells.
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  • 18
    Publication Date: 1984-06-01
    Description: Two new cell surface antigens specific for the erythroid lineage were defined with cytotoxic IgM monoclonal antibodies (McAb) (EP-1; EP-2) that were produced using BFU-E-derived colonies as immunogens. These two antigens are expressed on in vivo and in vitro derived adult and fetal erythroblasts, but not on erythrocytes. They are not detectable on resting lymphocytes, concanavalin-A (Con-A) activated lymphoblasts, granulocytes, and monocytes or granulocytic cells or macrophages present in peripheral blood or harvested from CFU-GM cultures. Cell line and tissue distributions distinguish McAb EP-1 and EP-2 from all previously described monoclonal antibodies. McAb EP-1 (for erythropoietic antigen-1) inhibits the formation of BFU-E and CFU-E, but not CFU-GM, colonies in complement-dependent cytotoxicity assays. By cell sorting analysis, about 90% of erythroid progenitors (CFU-E, BFU-E) were recovered in the antigen-positive fraction. Seven percent of the cells in this fraction were progenitors (versus 0.1% in the negative fraction). The expression of EP-1 antigen is greatly enhanced in K562 cells, using inducers of hemoglobin synthesis. McAb EP-2 fails to inhibit BFU-E and CFU-E colony formation in complement-dependent cytotoxicity assays. EP-2 antigen is predominantly expressed on in vitro derived immature erythroblasts, and it is weakly expressed on mature erythroblasts. The findings with McAb EP-1 provide evidence that erythroid progenitors (BFU-E and CFU-E) express determinants that fail to be expressed on other progenitor cells and hence appear to be unique to the erythroid lineage. McAb EP-1 and EP-2 are potentially useful for studies of erythroid differentiation and progenitor cell isolation.
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  • 19
    Publication Date: 1984-06-01
    Description: This study was undertaken to examine the interaction of platelet size and age in determining in vitro platelet function. Baboon megakaryocytes were labeled in vivo by the injection of 75Se- methionine. Blood was collected when the label was predominantly associated with younger platelets (day 2) and with older platelets (day 9). Size-dependent platelet subpopulations were prepared on both days by counterflow centrifugation. The reactivity of each platelet subpopulation was determined on both days by measuring thrombin-induced aggregation. Platelets were fixed after partial aggregation had occurred by the addition of EDTA/formalin. After removal of the aggregated platelets by differential centrifugation, the supernatant medium was assayed for remaining platelets and 75Se radioactivity. Comparing day 2 and day 9, no significant difference was seen in the rate of aggregation of a given subpopulation. However, aggregation was more rapid in the larger platelet fractions than in the smaller ones on both days. A greater percentage of the 75Se radioactivity appeared in the platelet aggregates on day 2 than on day 9. This effect was independent of platelet size, as it occurred to a similar extent in the unfractionated platelets and in each of the size-dependent platelet subpopulations. The data indicate that young platelets are more active than older platelets. This study demonstrates that size and age are both determinants of platelet function, but by independent mechanisms.
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  • 20
    Publication Date: 1984-08-01
    Description: We have measured the fully carboxylated (native) prothrombin antigen and the undercarboxylated (abnormal) prothrombin antigen in patients treated with sodium warfarin using specific immunoassays to evaluate a new approach for monitoring oral anticoagulant therapy. Plasma and serum samples (391) were assayed for the prothrombin time, native prothrombin antigen, and abnormal prothrombin antigen. The results were correlated with the presence of bleeding or thromboembolic complications at the time of phlebotomy. The native prothrombin antigen correlated with the occurrence of complications in 95% of samples. Of 13 samples from patients with bleeding complications, 13/13 (100%) had a native prothrombin of 12 micrograms/mL or lower. Of seven samples from patients with thromboembolic complications, 6/7 (86%) had a native prothrombin of 24 micrograms/mL or greater. By comparison, a prothrombin time index of 1.5 to 2.5, 1.5 to 2.2, 1.5 to 2.0, or 1.3 to 1.8 identified 6/20 (30%), 9/20 (45%), 11/20 (55%), or 12/20 (60%) patients at risk, respectively. Although the prothrombin time index did correlate with the presence of bleeding complications, the native prothrombin antigen correlated closely with the presence of bleeding and thromboembolic complications. According to these results, the native prothrombin antigen, maintained in a range of 12 to 24 micrograms/mL by regular adjustment of the warfarin dosage, may be associated with a reduced risk of complications due to excessive or insufficient warfarin therapy. On the basis of these preliminary data, we recommend that the native prothrombin antigen be considered to monitor warfarin therapy.
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  • 21
    Publication Date: 1984-06-01
    Description: High proliferative potential macrophage progenitor cells (HPP-CFC) in 5- fluorouracil (FU) treated and normal mouse bone marrow (BM) have been shown to be less sensitive to inhibition of proliferation by prostaglandins of the E series (PGE) than low proliferative potential macrophage progenitor cells (LPP-CFC) in normal BM in agar cultures. The growth of large colonies (diameter greater than 0.5 mm) derived from HPP-CFC in FU BM, which require a combination of macrophage colony- stimulating factor (CSF-1) plus a new growth factor called synergistic activity (SA), are inhibited by 50% in the presence of 5.5 X 10(-6) M PGE1. On the other hand, LPP-CFC in normal BM, which form smaller colonies (diameter less than or equal to 0.5 mm) in the presence of CSF- 1 alone, require only 5 X 10(-8) M PGE1 for the same level of inhibition. Addition of appropriate concentrations of PGE1 to the agar culture assay should improve detection of HPP-CFC by inhibiting the proliferation of LPP-CFC. These observations suggest that the apparent negative feedback control of macrophage production by PGE operates largely on the LPP-CFC, which respond to CSF-1 alone, and is probably not involved in the regulation of the more primitive HPP-CFC.
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  • 22
    Publication Date: 1984-05-01
    Description: We used both radiolabeled and fluorescein-labeled antiglobulins in assays to detect antibodies against platelets in multiply transfused patients to determine the value of these tests in predicting the outcome of platelet transfusion in such patients. In 15 allosensitized patients, we studied 68 single-donor platelet transfusions, 43 (63%) of which had a poor outcome, defined as a corrected count increment (CCI), less than 10,000. The results obtained with either test were significantly correlated with the CCI following transfusion (p less than 0.001), but the assay using the radiolabeled antiglobulin had slightly better sensitivity, specificity, and predictive value. When the assays were used in combination, there was again significant correlation with the CCI of the transfusion, p less than 0.001. When both assays predicted failure of the transfusions, 31/31 (100%) such transfusions resulted in a CCI of less than 10,000, and when both assays predicted success of the transfusions, 14/15 (93%) such transfusions resulted in a CCI of greater than 10,000. Both assays are useful in predicting the outcome of the platelet transfusions; when the assay results were concordant, almost total predictive accuracy was obtained.
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  • 23
    Publication Date: 1984-06-01
    Description: A 42-yr-old woman with systemic lupus erythematosus without bleeding diathesis developed a prolonged activated partial thromboplastin time that was not corrected by normal plasma. An inhibitor that acted rapidly and inactivated 0.5 U/ml plasma thromboplastin antecedent (PTA, factor XI) at a 1:200 plasma dilution was demonstrated. In addition to a low titer of PTA (less than 0.01 U/ml), plasma assayed at 20-fold dilution also showed low titers of Hageman (factor XII, 0.02 U/ml), Fletcher (plasma prekallikrein, 0.02 U/ml), and Fitzgerald (high molecular weight kininogen, less than 0.01 U/ml) factors. The titer of these factors, except PTA, returned to normal upon further plasma dilution or upon removal of the inhibitor by protein A adsorption. Thus, the inhibitor appeared to interfere with these clotting factor assays, possibly by inactivating PTA in the substrate plasmas in the test system. Its specificity was further confirmed. The inhibitor did not interfere with surface-induced proteolytic cleavage of Hageman factor. Surface-induced generation of plasma kallikrein activity (amidolysis of H-D-pro-phe-arg-pNa and cold-promoted factor VII activity enhancement) requires only Hageman, Fletcher, and Fitzgerald factors and was normal. Reactions requiring all 4 contact phase factors, including PTA, such as surface-induced generation of plasmin activity (amidolysis of H-D-val-leu-lys-pNa) and activated Christmas factor (factor IXa) activity, were defective. Furthermore, the inhibitor bound to agarose-protein A inactivated and removed PTA selectively from normal plasma. The inhibitor was an IgG-lambda autoantibody that precipitated PTA. The inactivated activated PTA (factor XIa) without the requirement for an additional cofactor. Furthermore, it inhibited surface-induced activation of PTA by interfering with its proteolytic cleavage upon glass surface exposure and with its binding onto the reactive surfaces.
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  • 24
    Publication Date: 1984-07-01
    Description: Because clinical disorders of spontaneous iron overload have no experimental counterpart, we studied iron distribution (atomic absorption analysis) and intestinal absorption (59Fe) in mice with hereditary alpha-thalassemia. Mice heterozygous for a radiation-induced alpha-Hb gene deletion exhibit a mild hemolytic anemia, like the human condition, with microcytosis, reticulocytosis, splenomegaly, and chemical evidence of defective alpha-chain synthesis. Quantitative iron determination showed that total iron content in spleen, liver, and kidney, but not heart or lung, of adult alpha-thalassemic mice was greater (P less than .05) than that in unaffected littermates. Iron concentration was also increased in liver (P less than .001), spleen (P = .025), kidney (P = .058), and heart (P = .010); in general, the greater the iron concentration in liver, the greater that in spleen (r = .39, P = .009), kidney (r = .70, P less than .001), and heart (r = .46, P less than .001). In mice examined 8 months postoperatively, splenectomy, as compared to sham operation, significantly raised iron content in extrasplenic tissues, but did not affect total body iron. At 10–11 weeks of age, but no longer at 12–14 weeks, thalassemic mice showed higher rates of iron absorption than age-matched controls. Thus, alpha-thalassemic mice display an early occurring iron absorption defect, leading to a modest, sustained, nonprogressive iron overload, and thereby represent a valuable model for exploring disorders of iron homeostasis.
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  • 25
    Publication Date: 1984-05-01
    Description: The role of divalent cations in platelet adherence to deendothelialized human arteries in flowing blood was investigated in an annular perfusion chamber. Spreading of platelets on the subendothelium was impaired below 30 microM of free Ca2+ ions (Ca2+). When Ca2+ was replaced by Mg2+, adherence was unchanged in perfusates without exogenous factor VIII-von Willebrand factor (FVIII-vWF), but the ability of FVIII-vWF to support platelet adherence was lost. Binding of FVIII-vWF to the vessel wall was independent of divalent cations, but bound FVIII-vWF was only able to mediate adherence after exposure to Ca2+. Pretreatment of FVIII-vWF with the calcium chelator EGTA (10 mM) resulted in loss of the ability to facilitate platelet adherence, while the ristocetin cofactor activity remained intact. Full restoration of the ability to mediate platelet adherence could only be obtained by prolonged dialysis against Ca2+ in the millimolar range. These data indicate that divalent cations have at least two separate roles to play in supporting platelet adherence: (1) platelet spreading on the subendothelium requires Ca2+ or Mg2+; (2) FVIII-vWF should be exposed to Ca2+ to obtain its optimal biologic activity in supporting platelet adherence.
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  • 26
    Publication Date: 1984-05-01
    Description: Peripheral blood granulocytes from patients with chronic myelogenous leukemia (CML) were studied for accessibility of membrane sialic acid and galactose residues to sodium borohydride-3H radiolabeling after oxidation with sodium metaperiodate (PI/B3H4) or with galactose oxidase (GO/B3H4). Granulocytes from untreated patients with chronic myelogenous leukemia showed increased radiolabeling with PI/B3H4, and decreased labeling with GO/B3H4 when compared to normal granulocytes. Granulocytes from leukemic patients receiving chemotherapy showed normal labeling patterns. Gel electrophoresis of membrane extracts showed that the changes in PI/B3H4 and GO/B3H4 reactivity of CML cells were distributed over all membrane protein bands. Our data suggest that CML granulocyte membrane proteins are aberrantly sialylated, with decreased accessibility of galactose residues, and that these changes may be reversed by clinical drug treatment.
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  • 27
    Publication Date: 1984-07-01
    Description: We present a colony assay system that allows in situ identification of human basophil/mast cell (basophil) colonies. In methylcellulose culture, in the presence of phytohemagglutinin-leukocyte conditioned media (PHA-LCM), human peripheral blood and bone marrow cells form colonies that can be distinguished by their unique morphological characteristics. Pure basophil colonies are diffuse, small colonies containing small, round, highly refractile cells. These characteristics of the constituent cells led us to the observation that a significant number of basophils are found in combination with eosinophils. The mixed eosinophil/basophil colonies have the distinctive elements of pure eosinophil and pure basophil colonies. Usually, these are diffuse colonies with compact clusters of slightly larger, darker-appearing cells. We also found colonies that contained basophils and neutrophils/monocytes, but this type could not be consistently identified by in situ morphology. Cytochemical analysis confirmed the metachromatic nature of the granules in the basophils. The presence of IgE receptors on the cells was documented by indirect immunofluorescent staining after passive sensitization with purified human IgE. Peripheral blood cells from six healthy volunteers formed 5.7 +/- 1.0 (mean +/- SEM) pure colonies in 2 X 10(5) cells. Cultures of bone marrow cells from patients with various types of anemia had 9.0 +/- 1.5 colonies in 10(5) cells. This is the first description of a colony assay system for in situ identification of a pure population of basophilic granulocytes.
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  • 28
    Publication Date: 1984-06-01
    Description: Morphological, immunologic, and functional properties of peripheral blood cells from two patients with chronic proliferations of granular lymphocytes are described. Cells from both patients showed a heterogeneous pattern from both a morphological and immunologic standpoint, indicating a polyclonal, rather than a monoclonal, expansion of these cells. In fact, both large and small-to-medium-sized granular lymphocytes were observed, and different percentages of positivity were found in the analysis with a large panel of monoclonal antibodies. Serologic and histologic features support the hypothesis that this lymphocytosis could be secondary to bacterial or viral infections rather than a primary event, suggesting that these patients may have chronic reactive immunoregulatory disorders.
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  • 29
    Publication Date: 1984-05-01
    Description: This report describes the experience of the Southeastern Cancer Study Group (SECSG) with a transport medium used for immunologic phenotyping of non-Hodgkin’s lymphomas. In a 2-mo pilot study, portions of 53 specimens of non-Hodgkin's lymphoma from four member institutions of the SECSG and affiliated community hospitals were sent by regular mail to a central laboratory. Immunologic phenotyping was carried out using a frozen section immunoperoxidase technique. In 48 of the cases, a clear-cut immunologic phenotype was obtained. Thirty-four tumors were of B cell origin and 7 had T cell markers. Six of the remaining lymphomas had neither B nor T cell markers, and the seventh had both. In 12 cases, phenotyping was also carried out at the originating institution using conventional cell suspension techniques; agreement between the two methods was excellent. The immunologic results were correlated with histopathologic diagnosis standardized using the Working Formulation for non-Hodgkin’s lymphomas. It was found that the low grade tumors were all B cell, but that the intermediate grade tumors were very heterogeneous immunologically. About one-fourth of the diffuse, intermediate grade or miscellaneous tumors had T cell markers. Our results indicate that immunologic phenotyping may be performed satisfactorily on transported material, making multiinstitution studies on the prognostic significance of immunologic phenotype in non- Hodgkin’s lymphomas feasible.
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  • 30
    Publication Date: 1984-05-01
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  • 31
    Publication Date: 1984-05-01
    Description: In the baboon (Papio species), the two nonallelic gamma-genes produce gamma-chains that differ at a minimum at residue 75, where isoleucine (I gamma-chain) or valine (V gamma) may be present. This situation obtains in baboons that are sometimes designated as Papio anubis, Papio hamadryas, and Papio papio. However, in Papio cynocephalus, although the I gamma-chains are identical with those in the above mentioned types, the V gamma-chains have the substitutions ala----gly at residue 9 and ala----val at residue 23. The V gamma-chains of P. cynocephalus are called V gamma C to distinguish them from the V gamma A-chains of P. anubis, etc. A single cynocephalus animal has been found to have only normal I gamma-chains and I gamma C-chains (that is, glycine in residue 9, valine in 23, and isoleucine in 75). When HbF is produced in response to stress with 5-azacytidine, P. anubis baboons respond with greater production than do P. cynocephalus, and hybrids fall between. Minimal data on P. hamadryas and P. papio suggest an even lower response than P. cynocephalus. As HbF increases under stress, the ratio of I gamma to V gamma-chains changes from the value in the adult or juvenile baboon toward the ratio in the newborn baboon. However, it does not attain the newborn value. The V gamma A and V gamma C-genes respond differently to stress. In hybrids, the production of V gamma A- chains exceeds that of V gamma C-chains. A controlling factor in cis apparently is present and may be responsible for the species-related extent of total HbF production. It may be concluded that the more primitive the cell in the erythroid maturation series that has been subjected to 5-azacytidine, the more active is the I gamma-gene.
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  • 32
    Publication Date: 1984-05-01
    Description: In the baboon (Papio species), the two nonallelic gamma-genes produce gamma-chains that differ at a minimum at residue 75, where isoleucine (I gamma-chain) or valine (V gamma) may be present. This situation obtains in baboons that are sometimes designated as Papio anubis, Papio hamadryas, and Papio papio. However, in Papio cynocephalus, although the I gamma-chains are identical with those in the above mentioned types, the V gamma-chains have the substitutions ala----gly at residue 9 and ala----val at residue 23. The V gamma-chains of P. cynocephalus are called V gamma C to distinguish them from the V gamma A-chains of P. anubis, etc. A single cynocephalus animal has been found to have only normal I gamma-chains and I gamma C-chains (that is, glycine in residue 9, valine in 23, and isoleucine in 75). When HbF is produced in response to stress with 5-azacytidine, P. anubis baboons respond with greater production than do P. cynocephalus, and hybrids fall between. Minimal data on P. hamadryas and P. papio suggest an even lower response than P. cynocephalus. As HbF increases under stress, the ratio of I gamma to V gamma-chains changes from the value in the adult or juvenile baboon toward the ratio in the newborn baboon. However, it does not attain the newborn value. The V gamma A and V gamma C-genes respond differently to stress. In hybrids, the production of V gamma A- chains exceeds that of V gamma C-chains. A controlling factor in cis apparently is present and may be responsible for the species-related extent of total HbF production. It may be concluded that the more primitive the cell in the erythroid maturation series that has been subjected to 5-azacytidine, the more active is the I gamma-gene.
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  • 33
    Publication Date: 1984-05-01
    Description: Fibrin prepared from 15 pathologic thrombi was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to determine the extent and pattern of fibrinolysis that occurs in vivo. Two groups of patients could be distinguished on the basis of the polypeptide chain composition of fibrin in their thrombi. Those patients who presented with acute vascular obstruction, either arterial or venous, showed a minimal degree of fibrin degradation, with a dominance of intact, undegraded crosslinked gamma-gamma dimers. On the other hand, patients with long-standing symptoms associated with chronic aortic aneurysms had thrombi containing extensively degraded fibrin. Thrombi in large aortic aneurysms were dissected into concentric layers that showed different degrees of fibrinolysis. The luminal surface consisted of fresh, red thrombus and contained undegraded crosslinked fibrin similar to that found in patients with acute occlusive disease. Deeper layers of the thrombus showed gamma-gamma chain degradation throughout, indicating that this portion was undergoing active thrombolysis. The findings demonstrate that the variability in the pathophysiologic balance between coagulation and fibrinolysis is reflected in vivo by the polypeptide chain composition of crosslinked fibrin in thrombi. The results support the hypothesis of a dynamic equilibrium between clotting and lysis, but indicate that the balance between these two processes may be distinctly different in separate areas of a single clot.
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  • 34
    Publication Date: 1984-06-01
    Description: The fucose-binding lectin from Lotus tetragonolobus ( FBL -L) has been previously shown to bind specifically to normal cells of the myeloid and monocytic lineages. The purpose of this study was to explore the utility of fluoresceinated FBL -L as a leukemia differentiation marker in conjunction with a panel of other frequently used surface markers (Fc receptor, HLA-DR, OKM1, and antimonocyte antibody). FBL -L reacted with leukemic cells in 8/9 cases of clinically recognized acute myeloid leukemia, including myeloid blast crisis of chronic granulocytic leukemia, 3/3 cases of chronic phase chronic myelogenous leukemia, and in 2/7 cases of clinically undifferentiated acute leukemia. Correlations were noted between reactivity with FBL -L, and DR and Fc receptor expression. Among continuous cell lines, FBL -L bound with high intensity to a majority of HL-60 and U937 cells. The less well differentiated myeloblast cell lines, KG-1, KG1a , and HL-60 blast II, exhibited less FBL -L binding than HL-60 and U937. A moderate proportion of K562 cells exhibited low level binding of FBL -L. Several lymphoblastic cell lines exhibited a pattern of low intensity binding that was distinguishable from the high intensity binding pattern of the myeloblastic lines. FBL -L reactivity of U937 was enhanced by induction of differentiation with leukocyte conditioned medium, but not dimethylsulfoxide. Such treatments induced contrasting patterns of change of HL-60 and U937 when labeled with OKM1, alpha-Mono, and HLA- DR. These studies demonstrate the application of FBL -L to analysis and quantitation of myelomonocytic leukemic differentiation.
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  • 35
    Publication Date: 1984-05-01
    Description: To investigate the cellular events that accompany erythroid hyperplasia, we studied several effects of erythropoietin (Epo) on marrow CFU-E in sickle cell anemia (SCA). We measured CFU-E number, CFU- E growth as a function both of Epo exposure time and of Epo concentration, and suppression of Epo-induced CFU-E formation by anti- Epo antiserum. With 0.5 U Epo/ml, the number of CFU-E was elevated in SCA (1,087 +/- 520) compared to normal (430 +/- 130). CFU-E were formed even when Epo was immediately neutralized by a 1/150 dilution of anti- Epo. After 40 hr of Epo exposure, only 2% of total CFU-E were expressed in normal marrow, whereas 12%-40% of CFU-E were expressed in SCA. Inhibition of CFU-E growth required at least 1/50 dilution of anti-Epo in SCA and a 1/300 dilution in normal marrow. In contrast to normal, a small number (5%-20%) of CFU-E were expressed in the absence of added Epo in SCA, and this pool required a 1/150 dilution of anti-Epo for inhibition. The Epo dose-response curve in SCA revealed a peak in colony formation around 0.1 U Epo/ml and 0.5 U Epo/ml, whereas only one peak at 0.5 U Epo/ml was seen in normals. These data strongly suggest that, in response to the demands of chronic erythroid hyperplasia in SCA, a pool of CFU-E is present characterized by increased in vitro sensitivity to Epo.
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  • 36
    Publication Date: 1984-07-01
    Description: Thirteen patients with acute leukemias that were difficult to classify by the use of cytochemical staining and terminal deoxyribonucleotidyl transferase (TdT) activity are reported. The phenotype of the leukemic cells was characterized by the presence of mature or early monocyte lineage antigens and intense Ia antigen expression detected by monoclonal antibodies, terminal deoxytransferase activity, and cytochemical features, including both Sudan black B and periodic acid- Schiff activity. The mean age of this group of patients was 60 years. Five patients had leukemia occurring after chemotherapy or radiotherapy of a prior malignant disease, and two patients had a refractory anemia prior to development of acute leukemia. These patients had a low response rate to chemotherapy. This series of leukemia appears to form a distinct nosologic entity, representing a leukemic transformation among early cells of the monocyte lineage, resulting in a predominant neoplastic cell that is less mature than either the French-American- British M4 acute myelomonocytic leukemia or M5 acute monoblastic leukemia. The presence of terminal deoxytransferase activity was interpreted as indicating the primitive state of the cells in the differentiation sequence, rather than as implying any significance with respect to lineage.
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  • 37
    Publication Date: 1984-04-01
    Description: Levels of platelet-associated IgG (PA-IgG) were studied in 72 patients with Hodgkin–s (HD) and non-Hodgkin–s lymphoma (NHL). Thirty-nine percent of patients with HD and 20% of patients with NHL had elevated PA-IgG levels. There was a positive correlation between disease activity and the presence of PA-IgG in HD and NHL. In patients with HD, PA-IgG strongly correlated with extent of disease and may serve as a marker of disease activity. PA-IgG may have facilitated platelet destruction in 5 of 11 thrombocytopenic patients with HD and increased PA-IgG and in 2 patients with HD and increased PA-IgG who developed severe thrombocytopenia when treated with chemotherapy.
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  • 38
    Publication Date: 1984-04-01
    Description: Sedimentation analysis of factor VIII complex was performed in the analytical ultracentrifuge using partition cells. This method allowed for the calculation of three different sedimentation coefficients from each run: one based on ristocetin agglutination activity for von Willebrand protein, SWF; one based on coagulant activity for factor VIIIC, SVIIIC; and one based on the schlieren or adsorption data for protein concentration, Sconc. In most cases, there was no agreement between the three values calculated from the same run, indicating a heterogeneous system. The calculated functional sedimentation coefficients give values that require the molecules to be highly asymmetric to be consistent with a glycoprotein of high molecular weight, which is in agreement with results observed in electron microscope studies. The dissociation of VIIIC into a smaller form can be demonstrated by this method. Determination of the three sedimentation coefficients in a series of fractions from gel filtration indicates a uniform size for the VIIIC activity but not for the WF activity. These observations are in agreement with the concept of a copolymer between WF and VIIIC and also with the concept of separate polymers for the two activities.
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  • 39
    Publication Date: 1984-04-01
    Description: The malignant monoclonal population in hairy cell leukemia (HCL) has been variously ascribed to be of myeloid, B, or even T cell origin. Recent data have been interpreted as suggesting that hairy cells (HC) may concomitantly or serially express both B and T surface determinants, a phenomenon which, if verified, would be unique among the lymphoproliferative malignancies. Data described here, however, demonstrate that (1) at least the majority of HCL are phenotypically of B cell derivation, and (2) the initial B cell phenotype is retained and solely expressed on cultured as well as phytohemagglutinin (PHA) activated monoclonal malignant HC.
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  • 40
    Publication Date: 1984-05-01
    Description: To study the influence of a biologic environment on cultured human leukemia cells, KG-1, KG-1a, and HL-60 cells were inoculated subcutaneously into newborn nude mice. The cells developed myelosarcomas at the site of inoculation and in lungs and kidneys. KG-1 and HL-60 myelosarcomas were successfully passaged through adult nude mice, whereas KG-1a tumors proliferated only after transplantation into newborn hosts. The human nature of the cells forming myelosarcomas in mice was assessed by chromosomal analyses and detection of cross- reactivity with an antibody to the human leukemia cell line K562. We undertook electron microscopic and cytochemical examinations of the cells proliferating in vitro and in the mice. The granules of KG-1 cells in vivo did not react for acid phosphatase, as observed in vitro, and the HL-60 cells proliferating in mice lost the perinuclear myeloperoxidase (MPO) demonstrated in cultured cells. Although the influence of an in vivo selection of cell subpopulations cannot be ruled out, the enzymatic changes are compatible with induced cell differentiation. Conclusive evidence of differentiation in vivo was observed in the KG-1a cell subline. The undifferentiated KG-1a blasts developed cytoplasmic granules and synthesized MPO during proliferation in vivo. These observations indicate that human leukemia cells from established cell lines proliferate in nude mice and may acquire new differentiated properties in response to the in vivo environment.
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  • 41
    Publication Date: 1984-05-01
    Description: The Southeastern Cancer Study Group conducted a post-remission induction randomized trial in adult acute myelogenous leukemia to assess the efficacy of alternate drug therapy during consolidation and of immunotherapy during maintenance. Of 508 evaluable patients entered into the study, 335 (66%) achieved a complete remission treated with a 7-day infusion of cytosine arabinoside at a dose of 100 mg/sq m/day and 3 days of daunorubicin at a dose of 45 mg/sq m/day. Those in remission were randomized to receive 3 courses of 1 of 3 consolidation regimens: (A) a continuous infusion of 5-azacytidine, 150 mg/sq m/day for 5 days; (B) 5-azacytidine plus beta-deoxythioguanosine, 300 mg/sq m/day for 5 days; or (C) cytosine arabinoside, 100 mg/sq m/day intravenously, and thioguanine, 100 mg/sq m orally every 12 hr, plus daunorubicin, 10 mg/sq m every 24 hr daily for 5 days. There was no difference in relapse rate among the 3 arms. Those completing consolidation and remaining in remission were randomized to 1 of 3 maintenance regimens: (D) chemotherapy, 5-day infusion of cytosine arabinoside and 2 days of daunorubicin (same doses as induction) given every 13 wk for 1 yr; (E) BCG given twice weekly for 1 mo and then monthly for 1 yr; or (F) the combination of regimens D and E. The median duration of remission was significantly better on regimen D (17.4 versus 9.4 and 9.5 mo), and median survival was 29 mo compared to 21 mo for the other regimens. Those given different drugs during consolidation than used for induction (regimens A and B) and subsequent chemotherapy for maintenance (regimen D) had the longest remission durations and survival. Immunotherapy was not as good as intensive chemotherapy for maintenance.
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  • 42
    Publication Date: 1984-05-01
    Description: Samples of leukemic cell DNA from 14 children with acute nonlymphocytic leukemia (ANLL) and 4 human myeloid leukemia cell lines were analyzed for rearrangement in the heavy chain region of the immunoglobulin gene. The diagnosis of ANLL was confirmed in all patients by morphological, cytochemical, and immunologic studies. By restriction endonuclease digestion and hybridization with cloned heavy chain immunoglobulin gene probes for the constant (Cmu) and joining (JH) regions, the DNA of 2 patients and 1 cell line (ML-1) was found to contain rearrangements. The DNA from the remaining 12 patients and 3 cell lines was not rearranged (germline configuration). Both patients with apparent immunoglobulin gene rearrangement achieved complete remission on therapy for ANLL. Immunoglobulin gene rearrangement in phenotypically defined ANLL suggests (1) that such changes may not be limited to lymphoid leukemia of B cell lineage, or (2) that, in some patients, the leukemic transforming event may involve stem cells capable of both B cell and myeloid differentiation.
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  • 43
    Publication Date: 1984-04-01
    Description: Patients with multiple myeloma (MM) are at an increased risk for infections with bacteria that require opsonization with complement. Because Streptococcus pneumoniae is the most frequently encountered pathogen in these patients, we investigated the ability of serum from patients with MM to mediate the binding of C3b, the major opsonin of the complement system, to S. pneumoniae. S. pneumoniae types 3, 14, and 25 were chosen for study, since S. pneumoniae type 3 activates primarily the classical complement pathway (CCP), type 25 primarily the alternative complement pathway (ACP), and type 14 both pathways. S. pneumoniae were treated with normal serum or serum from 17 patients with MM, and the bound C3b was quantified with fluorescein-conjugated anti-C3 in a spectrophotofluorometric assay. Despite normal or elevated serum concentrations of C3, total hemolytic complement, and C-reactive protein in all of the MM sera, factor B in 16/17 such sera, and C4 in 14/17 MM sera studied, all 17 sera demonstrated a defect in C3b binding to type 3 (32.7% +/- 6% of normal). In addition, serum from 15/17 patients bound decreased amounts of C3b to types 14 (39.6% +/- 8%) and 25 (52.2% +/- 8%). Mixing normal serum with MM serum restored MM C3b binding activity to all three S. pneumoniae types, suggesting that the defect was related to a deficiency rather than an inhibitor of C3 activation. Although MM patients are unable to produce specific antibodies to bacterial antigens, the addition of anti-S. pneumoniae antibodies to MM serum did not enhance C3b binding to any of the S. pneumoniae types. However, when S. pneumoniae were opsonized in a mixture of MM serum and C3-depleted normal serum, C3b binding was restored to all three S. pneumoniae types, demonstrating that MM C3 functions normally in the presence of other normal serum factors. In the present studies, the MM C3b binding defect appeared to correlate with the incidence of S. pneumoniae infections. Serum from patients with a history of an S. pneumoniae infection bound significantly less C3 (20.5% +/- 4%) than those study patients without a history of an S. pneumoniae infection (55.8% +/- 8%) (p less than 0.0025). Thus, MM serum has a defect in the activation of C3, and this may contribute to the increased susceptibility of MM patients to S. pneumoniae infections.
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  • 44
    Publication Date: 1984-12-01
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  • 45
    Publication Date: 1984-09-01
    Description: The effects of hemin on the conversion of pyruvate kinase (PK) isozymes from the M2-type to the L-type in K562 cells were investigated. Immunofluorescence, ion exchange chromatography, and electrophoretic studies showed that the untreated K562 cells contained only the M2-type PK, while eight to 20 days after induction with hemin, concomitant with hemoglobin F synthesis, L-type PK levels increased while M2-type PK levels decreased. Electrophoretic study revealed three hybrid isozymes of the L-type and M2-type PK. We conclude that the conversion of PK isozymes from the M2-type to the L-type in erythroid precursor cells occurs in the early stage of maturation.
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  • 46
    Publication Date: 1984-10-01
    Description: In this study, the effects of 5-aza-2′-deoxycytidine on differentiation of human leukemic cells in primary suspension culture are reported for the first time. Morphological and functional differentiation was induced in cells from two acute monoblastic leukemias and two of three acute myeloid leukemias following repeated exposures to 1 mumol/L 5-aza- 2′-deoxycytidine. The observation that nontoxic concentrations of the drug are able to induce the in vitro differentiation of both monoblastic and myeloblastic leukemic cells into mature elements may encourage the exploitation of the differentiating properties of 5-aza- 2′-deoxycytidine in chemotherapy protocols for acute non-lymphoblastic leukemias.
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  • 47
    Publication Date: 1984-10-01
    Description: We describe four patients with impaired platelet aggregation and 14C- serotonin secretion during stimulation with adenosine diphosphate (ADP), epinephrine, collagen, and platelet-activating factor. The response to arachidonic acid was normal in all patients with regard to aggregation and in three of the four with regard to 14C-serotonin secretion. The total platelet adenosine triphosphate (ATP) and ADP content and the ATP to ADP ratio was normal in all patients, thereby excluding storage pool deficiency as the cause of the secretion defect. Studies with 3H-arachidonic acid-labeled platelets revealed that the thrombin-induced liberation of arachidonic acid from membrane-bound phospholipids was impaired in these patients. Further, platelet thromboxane B2 production, measured using a radioimmunoassay, was diminished during stimulation with ADP and thrombin, but was normal with arachidonic acid, indicating that the oxygenation of arachidonic acid was normal and that the diminished thromboxane production was due to a defect in the liberation of arachidonic acid. Release of arachidonic acid is mediated by phospholipases that are Ca++ dependent. To examine whether these patients may have a defect in making intracellular Ca++ available, another Ca++-dependent process, myosin light chain phosphorylation, was studied during thrombin stimulation. Platelets from three of the patients were found to behave the same as normal ones, suggesting that the deficiency in phospholipase activity may not be due to impaired Ca++ mobilization. Our studies demonstrate a novel group of patients with platelet secretion defects associated with impaired liberation of arachidonic acid from phospholipids. These patients exemplify a congenital defect, other than deficiencies of cyclooxygenase and thromboxane synthetase, by which thromboxane production may be impaired in platelets.
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  • 48
    Publication Date: 1984-10-01
    Description: Restriction endonuclease mapping defined a partial deletion of about 1.35 kb in the beta-globin gene of a black American patient with hemoglobin S-beta zero-thalassemia and in his uncle with a beta zero- thalassemia trait. The 5′ endpoint of the deletion is about 600 bases upstream from the cap site, and the 3′ endpoint lies within about 500 bases from the 5 splice junction of the second intervening sequence. The deletion is different from that of a previously reported Indian beta zero-thalassemia allele, where 0.6 kb is deleted at the 3′ end of the beta-globin gene.
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  • 49
    Publication Date: 1984-12-01
    Description: Hereditary persistence of fetal hemoglobin (HPFH) is a genetically heterogeneous and clinically benign condition characterized by persistent expression of fetal hemoglobin (Hb F) into adulthood. In the G gamma beta + type, no major deletions in the globin gene cluster occur; adult heterozygotes produce approximately 20% Hb F, which results from overproduction of G gamma chains, with no apparent increase in production from the adjacent A gamma gene. We have recently described a point mutation 202 base pairs 5′ to the cap site of the G gamma gene in an individual with G gamma beta + HPFH. This mutation abolishes a normal ApaI restriction endonuclease site, and thus can be detected by blotting of genomic DNA. We present here further data on the ApaI mutation: (1) It occurs in six of seven families with G gamma beta + HPFH. (2) In three families, detailed haplotype analysis using 11 polymorphic restriction sites in the beta globin cluster has been done. The two that carry the missing ApaI site are identical but the third, which has a normal ApaI pattern, differs from the other two in at least two sites, one of which is a new polymorphic Nco I site between the delta and beta globin genes. This suggests the possibility of a different HPFH mutation in the third family. (3) The haplotype of the G gamma beta + HPFH chromosome carrying the ApaI mutation is different from that of 108 beta A chromosomes of black individuals that have been tested. (4) The G gamma ApaI site is normal in 61 beta A and 109 beta S alleles from non-HPFH black individuals, including 22 who share the same haplotype for the intragenic G gamma, A gamma HindIII polymorphisms. These data add support to the possibility that the -202 mutation is actually causative of the G gamma beta + HPFH phenotype.
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  • 50
    Publication Date: 1984-10-01
    Description: Potential limitations of prenatal diagnosis of hemophilia B, as compared to hemophilia A, include (1) occurrence of far more frequent defects with abnormal circulating antigen, (2) lower levels of factor IX in fetal plasma at 16 to 20 weeks gestation, and (3) the presence of factor IX antigen in amniotic fluid. In addition, proteolysis could occur, especially with amniotic fluid contamination of fetal plasma. A sensitive polyclonal immunoradiometric assay for factor IX antigen was used to characterize the range of levels in amniotic fluids and fetal plasma samples. To assess for altered forms, factor IX species were compared to those of a homologous clotting factor, prothrombin. Fourteen postmortem abortus blood samples from fetuses of 14 to 23 weeks gestation had factor IX antigen levels that averaged 5.1 U/dL and ranged from 1.7 to 15 U/dL. Amniotic fluid factor IX antigen averaged 2.9 U/dL, with a range from 1.4 to 8.5 U/dL in 19 separate amniocentesis samples. Thus, in a male fetus at risk of hemophilia B and with a low circulating level of gene product, mixture of fetal plasma with amniotic fluid could severely limit prenatal diagnosis, assuming that the amniotic fluid factor IX is of maternal origin. Despite rapid processing of amniotic fluid samples, the prothrombin was extensively cleaved, suggesting that it had been activated in vivo. On gel electrophoresis of amniotic fluid samples, however, factor IX was only minimally cleaved. In the postmortem fetal blood specimens, prothrombin was partially cleaved. On crossed-immunoelectrophoresis, fetal plasma prothrombin showed decreased migration in calcium, compared to EDTA, indicative of mature gamma-glutamyl carboxylation. The latter presumably resulted from fetal hepatic synthesis.
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  • 51
    Publication Date: 1984-09-01
    Description: Colony-forming cells in ten cases of acute myeloid leukemia (AML) were studied with six cytotoxic monoclonal antibodies that react with antigens expressed at discrete stages of differentiation of normal and leukemic hematopoietic cells. The reactivity of the whole leukemic population was measured by indirect immunofluorescence, and the reactivity of the colony-forming cells was established by complement- mediated cytotoxicity and by fluorescence activated cell sorting. Comparison of the immunofluorescent reactivity with cytotoxicity and cell sorting showed that colony-forming cells were found within a fraction of the leukemic subpopulations that expresses these antigens. This finding implies that immunofluorescence reactivity of the total leukemic population does not necessarily predict the phenotype of the clonogenic cells. When the surface phenotype of the clonogenic leukemic cells was compared to that previously established for normal marrow hemopoietic clonogenic cells, several patterns were seen: (1) in four of ten cases, the clonogenic cells expressed a phenotype like that of relatively mature normal granulocyte-macrophage colony-forming cells (late CFU-GM) or, (2) in two cases, a phenotype similar to the less mature colony-forming cells (early CFU-GM or CFU-GEMM), and (3) in four cases, a composite phenotype of early and late CFU-GM. Thus, the level of impairment of differentiation in AML may vary from case to case. In those cases phenotypically similar to the late CFU-GM, it may be possible to separate leukemic clonogenic cells from less mature normal clonogenic cells using monoclonal antibodies selectively cytotoxic for the late CFU-GM.
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  • 52
    Publication Date: 1984-09-01
    Description: We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A.
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  • 53
    Publication Date: 1984-09-01
    Description: Human monocytes generate the procoagulant tissue factor (MTF) following exposure to a variety of immune stimuli in vitro. The generation of MTF is modified by T cells, lymphokines, and immunoregulatory lipoproteins, and recent studies have shown that MTF can be activated in an immune- specific manner following exposure to antigen. We have examined the role of serum factors in the regulation of MTF generation. Low concentrations (less than 1%) of heat-inactivated normal human serum greatly enhanced MTF generation in cultures of normal peripheral blood mononuclear cells. The stimulatory effect was observed in cultures of both unstimulated cells and cells exposed to bacterial lipopolysaccharide. Stimulation was not observed at high serum concentrations (greater than 10%) and could not be explained by endotoxin contamination or activation of the assay system. Stimulatory activity was present in plasma and BaSO4-adsorbed plasma as well as autologous and allogeneic serum, was not abolished by removal of serum lipoproteins, and did not require the presence of T cells for its expression. Sera from 28 different normal volunteers were screened for stimulatory activity and demonstrated a wide variation in potency. These results suggest that a potent factor is present in sera that enhances the expression of MTF activity in vitro. This factor is distinct from previously described lipoprotein regulators and may play a role in the initiation of coagulation in both normal hemostasis and pathologic states.
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  • 54
    Publication Date: 1984-04-01
    Description: Non-Hodgkin's lymphoma (NHL) is a very rare complication of acute lymphoblastic leukemia (ALL). We present the pathologic, clinical, immunologic, and ultrastructural features of the third reported example of NHL following successfully treated ALL. This white girl developed ALL with predominantly L1 cells at 3.5 yr of age. The lymphoblasts were terminal deoxynucleotidyl transferase (TdT) positive and were non-B, non-T cells. She achieved a complete remission with standard induction therapy and has remained in continuous complete remission. Four and one- third years after the onset of ALL, she developed multifocal, pleomorphic large cell lymphoma of the small bowel, which resulted in episodes of intussusception and obstruction. These pleomorphic and frequently multinucleated lymphoma cells lacked TdT, common ALL antigen, and all tested markers of B cell, T cell, and histiocyte differentiation. Following three small bowel resections, systemic multiagent chemotherapy, and abdominal irradiation, she is currently free of disease.
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  • 55
    Publication Date: 1984-11-01
    Description: Leukemia in the newborn is an infrequent disease that has not been well defined using modern laboratory techniques. We describe two infants, one at birth and one at four weeks, with acute lymphoblastic leukemia. The blasts from each patient were studied in great detail, using a battery of cytochemical and immunologic procedures in addition to ultrastructural studies. Immunologic cell marker studies, not previously reported in congenital leukemia, showed the lymphoblasts from each infant to be of the pre-B cell phenotype. Each infant relapsed, one after a 17-week clinical remission and the other after a 44-week remission. The former has died while the latter is in a second remission. The subtype of pre-B cell acute lymphoblastic leukemia (ALL) which in childhood appears to confer an unfavorable prognosis, may have the same significance in neonatal ALL.
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  • 56
    Publication Date: 1984-04-01
    Description: The proliferation and differentiation of granulocyte and monocyte progenitor cells (CFU-C) in vitro is dependent on the presence of a group of closely related glycoproteins termed colony-stimulating factors (CSF). In order to investigate the interaction of these factors with CFU-C, we purified CFU-C from the peripheral blood of chronic myeloid leukemia patients with an immune rosette technique using specific monoclonal antibodies (mean 74-fold enrichment, 45% cloning efficiency). Colony formation by purified CFU-C demonstrated an absolute dependence on an exogenous source of CSF. Liquid culture of small aliquots of enriched CFU-C with CSF-containing medium resulted in a rapid, time- and concentration-dependent induction of DNA synthesis as measured by 3H-thymidine incorporation. This specific CSF induction of DNA synthesis by enriched CFU-C was used to develop a microassay system for CSF activity. CSF activity could be reproducibly quantitated in 24–48 hr. The proliferating cells in this assay system were shown to be myeloid progenitor cells by examining the morphology of their progeny and by determining the surface antigen phenotype of the responding cells (Ia+, T3-, B1-, Mo1-). This microassay provides a quantitative assessment of CSF activity that may be useful in the purification of human CSF and in the generation of monoclonal antibodies to CFU-C surface structures.
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  • 57
    Publication Date: 1984-09-01
    Description: Colony-forming cells in ten cases of acute myeloid leukemia (AML) were studied with six cytotoxic monoclonal antibodies that react with antigens expressed at discrete stages of differentiation of normal and leukemic hematopoietic cells. The reactivity of the whole leukemic population was measured by indirect immunofluorescence, and the reactivity of the colony-forming cells was established by complement- mediated cytotoxicity and by fluorescence activated cell sorting. Comparison of the immunofluorescent reactivity with cytotoxicity and cell sorting showed that colony-forming cells were found within a fraction of the leukemic subpopulations that expresses these antigens. This finding implies that immunofluorescence reactivity of the total leukemic population does not necessarily predict the phenotype of the clonogenic cells. When the surface phenotype of the clonogenic leukemic cells was compared to that previously established for normal marrow hemopoietic clonogenic cells, several patterns were seen: (1) in four of ten cases, the clonogenic cells expressed a phenotype like that of relatively mature normal granulocyte-macrophage colony-forming cells (late CFU-GM) or, (2) in two cases, a phenotype similar to the less mature colony-forming cells (early CFU-GM or CFU-GEMM), and (3) in four cases, a composite phenotype of early and late CFU-GM. Thus, the level of impairment of differentiation in AML may vary from case to case. In those cases phenotypically similar to the late CFU-GM, it may be possible to separate leukemic clonogenic cells from less mature normal clonogenic cells using monoclonal antibodies selectively cytotoxic for the late CFU-GM.
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  • 58
    Publication Date: 1984-04-01
    Description: A complement (C)-dependent antiglobulin assay was utilized to determine the reactivity of non-C-fixing monoclonal antibodies (MoAb) with human granulocyte-macrophage progenitor cells (CFU-GM). The variables of the assay were analyzed with non-C-fixing MoAb against Ia antigens, including CR11–462, which recognizes the same (or spatially close) determinant identified by the C-fixing anti-Ia MoAb Q5/13. The sensitivity of the antiglobulin assay was influenced by dilutions of anti-mouse Ig xenoantiserum and of rabbit C. Five non-C-fixing MoAb to Ia antigens, seven non-C-fixing MoAb to HLA-A,B antigens, and one non-C- fixing MoAb to beta 2-microglobulin induced marked inhibition of human CFU-GM in the antiglobulin assay. The activity of non-C-fixing MoAb in the antiglobulin assay was comparable to that of C-fixing anti-Ia and anti-HLA-A,B MoAb in the standard cytotoxicity assay. In addition, the cytotoxic effect of dilute C-fixing anti-Ia MoAb was enhanced when the antiglobulin technique was employed. The results of this study indicate that the antiglobulin assay is a rapid and simple technique for the characterization of antigens on human hematopoietic progenitors. Our data also indicate that Ia antigens are expressed on most CFU-GM and that the conflicting results in the literature (that is, those suggesting that Ia antigens are expressed on a smaller proportion of CFU-GM) may reflect differences in the cytolytic activity of the MoAb and rabbit C used.
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  • 59
    Publication Date: 1984-04-01
    Description: Serum cobalamin (vitamin B12) and unsaturated B12 binding capacity (UBBC) have been measured in 24 cases of hypereosinophilia: 16 were cases of hypereosinophilic syndrome (HES) and 8 of secondary eosinophilia. The two groups were similar with respect to absolute eosinophil counts. Serum cobalamin and UBBC were found to be markedly increased in most cases of HES and normal in secondary eosinophilia. This elevation of UBBC was mainly related to the increase of R binders (transcobalamins I and III). The elevated serum cobalamin and R binders in HES were due neither to a higher intracellular content of R binders nor to an increased release of these binders from eosinophils of HES. Pure fractions of eosinophils obtained from HES and secondary eosinophilia did not exhibit any difference in vitamin B12 binders. On the other hand, neutrophil-rich fractions from the same patients showed a higher content of intracellular B12 binding proteins than pure eosinophil fractions, irrespective of the cause of eosinophilia. These findings suggest that the increased serum vitamin B12 and UBBC could reflect an expanded pool of both eosinophils and neutrophils in HES and, thus, provide an additional argument for the inclusion of this syndrome in the group of myeloproliferative disorders.
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  • 60
    Publication Date: 1984-04-01
    Description: The present studies report erythropoietin (Ep) production in primary cultures of a human renal carcinoma from a patient with erythrocytosis that has been serially transplanted to BALB/c nude mice. The levels of erythropoietin in the culture media were estimated using the exhypoxic polycythemic mouse assay (EHPCMA), fetal mouse liver erythroid colony- forming technique (FMLC), and a radioimmunoassay (RIA). The spent culture media of the exponentially growing cells contained less than 10 mU/ml of Ep measured by RIA. However, after the cells became confluent, Ep levels (RIA) in the spent media showed a marked increase to approximately 300 mU/ml. Ep levels estimated using the FMLC and EHPCMA were approximately 2/3 and 1/10, respectively, of those measured by RIA. Rabbit antiserum to highly purified human urinary Ep (70,400 U/mg protein) was utilized for immunocytochemical (peroxidase-antiperoxidase method) localization of Ep in the cultured cells. Very few of the cells in exponential growth exhibited Ep-like immunoreactivity, whereas intense Ep-like immunoreactivity was observed in the cytoplasm of the cells maintained in culture for a prolonged period after reaching confluency. The most intense staining was observed in some of the cells forming domes. The domes developed after the cells reached confluency, and their numbers increased with increasing time in confluent culture, in parallel with the increase in Ep levels in the spent media. This primary cell culture system of a renal cell carcinoma maintained in nude mice, which produces immunologically and biologically active Ep, may provide a useful model for studies of the mechanism of Ep production.
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  • 61
    Publication Date: 1984-04-01
    Description: We assessed the number of Langerhans cells (LC) before and after bone marrow transplantation (BMT) in 27 patients in order to study the fate and behavior of these dendritic antigen-presenting cells following allogeneic BMT. LC were identified using monoclonal antibody OKT6 on skin biopsies performed on days - 10, 0, 11, 25, 39, 120, and 365. In a control group composed of 15 healthy adults aged 20–37 yr, the mean number of LC (+/- SEM) was 25.6 +/- 1.17/0.1 sq mm of epidermal surface. Our study shows that pretransplant, the number of LC in patients with aplastic anemia or leukemia was lower than that of controls. The finding of low numbers of LC in patients with untreated aplastic anemia is suggestive of a medullary origin of LC in man. Moreover, during the early posttransplant period, nearly all patients present a severe deficit in LC. This deficit may delay the maturation of their immune system. The number of LC reaches nearly normal levels 4– 12 mo after BMT. Finally, we have noted a significant impairment of LC reconstitution in patients with acute graft-versus-host disease (GVHD), providing evidence that this defect may be an important mechanism involved in acute GVHD-related immunodeficiency.
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  • 62
    Publication Date: 1984-04-01
    Description: The acute effects of a single intravenous dose of L-asparaginase on protein synthesis were studied in normal rabbits and in animals that had received turpentine to stimulate fibrinogen production. Male New Zealand rabbits received L-asparaginase (500 U/kg) 16 hr before the injection of the radiolabeled amino acid [75Se]selenomethionine (75SeM). Incorporation of 75SeM into fibrinogen and serum proteins in the L-asparaginase-treated rabbits was the same as for saline-treated controls, with fibrinogen representing approximately 5% of the labeled plasma proteins. In turpentine-treated rabbits, the maximal incorporation of 75SeM into serum proteins remained unchanged, whereas 75SeM-fibrinogen increased sixfold and accounted for 25% of the labeled proteins. Animals that received L-asparaginase at the same time as turpentine or 14 hr later showed significant decreases in synthesis of both serum proteins and fibrinogen. 75SeM-fibrinogen that was purified from L-asparaginase-treated rabbits underwent normal catabolism when injected into normal recipient rabbits. These data indicate that L- asparaginase can acutely cause partial inhibition of both serum protein and fibrinogen synthesis when administered to rabbits shortly before or during a period of increased fibrinogen production. Fibrinogen that is synthesized in the presence of L-asparaginase does not have an abnormal rate of catabolism.
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  • 63
    Publication Date: 1984-04-01
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  • 64
    Publication Date: 1984-04-01
    Description: 1,(2-Chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) and other chloroethylnitrosourea anticancer agents in clinical use produce severe and cumulative bone marrow toxicity. Chlorozotocin, a glucose analogue, has demonstrated reduced hematologic toxicity while retaining full antitumor activity. The biochemical-pharmacologic properties of chlorozotocin and CCNU were compared in human bone marrow. After a 2-hr incubation with a 0.1-mM drug concentration, total cellular uptake of chlorozotocin in whole marrow was 2.47 +/- 0.80 pmole/10(4) cells and was not significantly different compared to the uptake of 1.94 +/- 0.53 pmole/10(4) cells with CCNU. The quantitative alkylation of bone marrow DNA by chlorozotocin, 22.8 +/- 1.2 pmole/mg DNA, was equivalent to that produced by CCNU, 22.9 +/- 0.5 pmole/mg DNA. Bone marrow was separated into 14 fractions by centrifugal elutriation. CCNU uptake was found to be greater than that of chlorozotocin in 3 fractions that were primarily composed of lymphocytes, monocytes, and normoblasts. Chlorozotocin uptake was greater than CCNU in 6 fractions that contained primarily mature and immature myeloid cells as well as the highest CFU-GM activity. The two drugs produced a comparable degree of DNA strand breakage and DNA-protein cross-linking as measured by alkaline elution of pooled fractions of elutriated bone marrow. DNA interstrand crosslinking was not found with either drug. The most significant finding of this study is the differences in the site of drug alkylation by chlorozotocin and CCNU in bone marrow chromatin. Endonuclease digestions with MCN, DNase I, and DNase II showed nonrandom alkylation of specific regions of chromatin by the two drugs: CCNU demonstrated a preferential binding to the transcriptionally active regions of chromatin, whereas chlorozotocin predominantly alkylated the transcriptionally inactive regions. These data suggest that the lethal damage of nitrosourea alkylation in human bone marrow is principally expressed in transcriptionally active regions of chromatin.
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  • 65
    Publication Date: 1984-03-01
    Description: Tumor burden in adult patients with acute leukemia is assessed using the percentage of blast cells in the bone marrow or blood. It is clear, however, that not all blast cells are leukemic cells, especially during rapid marrow regeneration. Similarly, some leukemia cell lines have been shown to differentiate in vitro, and the same process also occurs in vivo. Therefore, the leukemic burden may be due to more differentiated cells as well as to blast cells. The purpose of this study was to investigate whether the human malignancy-associated nucleolar antigen (HMNA) could be used as a marker for leukemic cells and to examine its potential as a diagnostic tool. The proportion of HMNA-positive cells in the bone marrow of patients with acute leukemia was determined by indirect immunofluorescence with antibodies to HMNA and was compared with the differential counts routinely made in the clinic laboratory. The percentages of HMNA-positive cells among the nucleated cells in the marrow of 72 patients with clinical evidence of leukemia were significantly higher (range 9%-98%, median 83%) than those observed for nonleukemic individuals (range less than 0.05%-2.5%, median 1%) or for fractions of marrow cells from normal volunteers enriched for normal early progenitor cells (less than or equal to 2%). Patients with leukemia in remission had a lower percentage of HMNA- positive cells (range 0%-83%, median 3%). The percentage of HMNA- positive cells increased as patients approached relapse. Although the percentage of HMNA-positive cells was related to the percentage of blast cells in the bone marrow of the patients with leukemia, some partially differentiated cells were also HMNA-positive in some specimens, and some blastic cells were HMNA-negative in other specimens. These studies indicate the potential usefulness of HMNA as a marker for leukemic cells.
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  • 66
    Publication Date: 1984-03-01
    Description: Kidney allografting was performed in a group of ten beagles, and viable leukocytes infiltrating the transplanted organs were isolated during episodes of acute rejection 5 or 6 days postoperatively. These infiltrate populations, consisting predominantly of lymphocytes and monocytes/macrophages, were found to have significantly increased amounts of procoagulant activity relative to control leukocytes isolated from circulating blood and lymph. Using nonspecific esterase staining in an agar microclot assay, procoagulant activity in the infiltrate leukocytes was found to reside in monocytes/macrophages rather than other coisolated cell types. By contrast, control monocytes from blood had no activity in this microclot assay. Procoagulant activity in the infiltrate cells was characterized as tissue factor. Increased amounts of this activator of the extrinsic pathway, as found in infiltrate monocytes/macrophages, may initiate clotting reactions and fibrin deposition within allografts.
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  • 67
    Publication Date: 1984-04-01
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  • 68
    Publication Date: 1984-03-01
    Description: A case of transcobalamin II deficiency with several unique features is described. The clinical presentation was typical, except for a slightly delayed age at presentation and the occurrence of apparent neurologic dysfunction from the beginning. The unusual biochemical feature was a low serum cobalamin level (97 pg/ml). Several cobalamin-binding protein abnormalities coexisted and antedated cobalamin therapy. Chief among these was the complexing of all serum R binder (transcobalamin I), leaving the patient with no detectable R binder. This defect appeared to be transient. Noteworthy, too, was a prominent binder of 70,000 mol wt that also carried the bulk of his serum cobalamin after therapy; it was prominent in his presumably heterozygous relatives too. The interrelationship between all these abnormalities is intriguing but unclear. The abnormality in transcobalamin II deficiency is clearly not limited solely to deficiency of transcobalamin II. It is also evident that this entity must now be considered in the differential diagnosis of low serum cobalamin levels in infancy.
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  • 69
    Publication Date: 1984-03-01
    Description: We have shown previously that the cause of anemia in healthy elderly subjects can usually not be identified. In this study, hematopoiesis was examined in 18 healthy elderly subjects with unexplained anemia and in 15 young and 15 healthy elderly individuals without anemia. No reduction in circulating testosterone was noted, making decreased androgen levels as a cause for the anemia unlikely. The 2,3 diphospho- glycerate (2,3DPG) levels in the anemic subjects were significantly higher than their corresponding controls, suggesting that the anemia was pathologic, as no increase would be expected if the low hemoglobin was a physiologic adjustment to age. The anemia was associated with a reduction in marrow normoblast and CFU-E number, but no decrease in BFU- E levels was seen. This suggests that the mechanism of the anemia is a decrease in stem cell proliferation. This could be caused by a reduction in circulating erythropoietin or a defect in end organ response. A second possibility is that a basic cellular abnormality exists. The presence of an overall reduction in hematopoiesis in anemic elderly (decreased peripheral blood counts, reduced marrow myeloid precursors, and CFU-C levels) makes this especially likely. The abnormality may be caused by a mechanism unrelated to the aging process. The fact that nonanemic elderly also have reductions in hematopoiesis suggests that age contributes to the defect.
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  • 70
    Publication Date: 1984-03-01
    Description: A simple technique using an aggregometer and fixed washed human platelets (FWP) and fibrillar collagen has been used to evaluate the contribution of the two components of the factor VIII (FVIII) complex to platelet-collagen interactions. FWP bound individually to collagen fibrils in suspension, and both the total number of FWP bound and the rate of adhesion increased with increasing collagen concentration. Von Willebrand's disease (vWD) type I or normal plasma immunoadsorbed with anti-factor VIII-related antigen (anti-FVIIIR:Ag) antiserum gave 20% and vWD type IIa gave 50% of the rate of adhesion obtained with normal, hemophilia A, or hemophilia A with inhibitor plasma, but the same percent adhesion was found with all plasmas. The rate of adhesion of both vWD type I and type IIa was corrected by the addition of purified FVIII complex. These results indicated that the FVIIIR:Ag and not the factor VIII coagulant activity (FVIII:C) in normal plasma or purified FVIII complex caused an accelerating effect on the rate at which FWP bound to collagen. Collagen fibrils not only bound FWP, but also adsorbed the FVIII complex with preferential adsorption of the forms of FVIIIR:Ag with the greatest ristocetin cofactor (FVIIIR:RCoF) activity. Saturation of collagen with FWP did not change the adsorption pattern of the FVIII complex. Also anti-FVIIIR:Ag blocked the accelerating effect of the FVIII complex but not the adhesion of FWP. Thus, FWP and FVIIIR:Ag appeared to bind to separate sites on collagen.
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  • 71
    Publication Date: 1984-03-01
    Description: The infusion of 1-deamino-(8-D-arginine)-vasopressin (DDAVP) causes not only an elevation in factor VIII-related antigen (FVIIIR:Ag), but also a marked elevation of plasma von Willebrand antigen II (vWAgII). vWAgII reaches a peak concentration at 60 min and is elevated 3–8-fold over basal levels in normal individuals and individuals with type I, IIA, and IIB von Willebrand's disease. As the mechanism of hemostatic alteration brought about by DDAVP might be due to release of endothelial cell proteins, endothelial cell cultures were performed. The cultures demonstrated synthesis and secretion of vWAgII, as evidenced by the incorporation of 35S-methionine into the vWAgII molecule. Thus, vWAgII, like FVIIIR:Ag, is an endothelial cell protein.
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  • 72
    Publication Date: 1984-09-01
    Description: The level of assimilation of dietary iron is believed to have an important influence on iron status. To examine the effect of enhancing the availability of dietary iron on iron balance, 17 adult volunteer subjects were given 2 g of ascorbic acid daily with meals for 16 weeks. Serum ferritin levels before and after the study averaged 46 and 43 micrograms/L, respectively, indicating a negligible effect on iron stores. When vitamin C supplementation was continued for an additional 20 months in five iron-replete and four iron-deficient subjects, serum ferritin determinations again failed to indicate any significant effect of the vitamin C on iron reserves. These findings were not explained by intestinal adaptation to the enhancing effect of the vitamin, because radioisotopic measurements of nonheme iron absorption showed no reduction in the enhancing effect of 1 g of ascorbic acid after four months of megadoses of vitamin C. It is concluded that altering the availability of nonheme dietary iron has little effect on iron status when the diet contains substantial amounts of meat.
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  • 73
    Publication Date: 1984-10-01
    Description: Potential limitations of prenatal diagnosis of hemophilia B, as compared to hemophilia A, include (1) occurrence of far more frequent defects with abnormal circulating antigen, (2) lower levels of factor IX in fetal plasma at 16 to 20 weeks gestation, and (3) the presence of factor IX antigen in amniotic fluid. In addition, proteolysis could occur, especially with amniotic fluid contamination of fetal plasma. A sensitive polyclonal immunoradiometric assay for factor IX antigen was used to characterize the range of levels in amniotic fluids and fetal plasma samples. To assess for altered forms, factor IX species were compared to those of a homologous clotting factor, prothrombin. Fourteen postmortem abortus blood samples from fetuses of 14 to 23 weeks gestation had factor IX antigen levels that averaged 5.1 U/dL and ranged from 1.7 to 15 U/dL. Amniotic fluid factor IX antigen averaged 2.9 U/dL, with a range from 1.4 to 8.5 U/dL in 19 separate amniocentesis samples. Thus, in a male fetus at risk of hemophilia B and with a low circulating level of gene product, mixture of fetal plasma with amniotic fluid could severely limit prenatal diagnosis, assuming that the amniotic fluid factor IX is of maternal origin. Despite rapid processing of amniotic fluid samples, the prothrombin was extensively cleaved, suggesting that it had been activated in vivo. On gel electrophoresis of amniotic fluid samples, however, factor IX was only minimally cleaved. In the postmortem fetal blood specimens, prothrombin was partially cleaved. On crossed-immunoelectrophoresis, fetal plasma prothrombin showed decreased migration in calcium, compared to EDTA, indicative of mature gamma-glutamyl carboxylation. The latter presumably resulted from fetal hepatic synthesis.
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  • 74
    Publication Date: 1984-09-01
    Description: This article describes three patients with megakaryoblastic leukemia, in whom the blast cells were identified as megakaryoblasts by the platelet peroxidase (PPO) reaction. More than 70% of the blasts in these patients were positive for the PPO reaction. Ultrastructurally, acid phosphatase activity in the megakaryoblasts was detected in the nuclear envelope, the endoplasmic reticulum, and in a few granules, but not in the Golgi cisternae. Some blast cells were identified by immunofluorescence or immunoalkaline phosphatase, using monoclonal antiplatelet glycoprotein IIb/IIIa antibody. In one patient, most of the blasts were positive for anti-HLA-DR monoclonal antibody. The possible order of the appearance of markers in the maturation of the megakaryocytic cell lineage is postulated, based on the data from the present cases and those previously reported. PPO activity appears in very immature cells, which retain Ia-like antigens. Platelet-specific glycoprotein IIb/IIIa is seen in immature cells that are only recognized by PPO activity.
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  • 75
    Publication Date: 1984-10-01
    Description: Prothrombin deficiency has been known to occur in association with lupus inhibitors for over 25 years. We studied 21 patients with lupus inhibitors and found that four of five with prothrombin deficiency and ten of 16 with quantitatively normal prothrombin had abnormal prothrombin crossed-immunoelectrophoresis (CIEP) characterized by material moving slower in the first dimension of electrophoresis than normal prothrombin. In two patients with prothrombin deficiency, all prothrombin measured by quantitative assay and all slow-moving material on CIEP were removed by treatment with Staphylococcal protein A (SPA). These patients had free antibody, which bound to normal plasma prothrombin, forming larger amounts of slow-moving material on CIEP. A third patient with prothrombin deficiency had only partial removal of prothrombin after SPA treatment. Two patients with quantitatively normal prothrombin had all slow-moving material on CIEP and about one fourth of the prothrombin by quantitative assay removed by SPA treatment. There was no correlation among the strength of the inhibitor, the presence of a “cofactor effect,” and the prothrombin abnormality. These data suggest that heterogeneous antiprothrombin antibodies, with or without prothrombin deficiency, are present in the majority of patients with lupus inhibitors.
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  • 76
    Publication Date: 1984-02-01
    Description: Two patients with chronic myeloid leukemia (CML) showed previously undescribed variants of a “masked” Ph1 abnormality. The first patient had the karyotype 46,XY, + 21, -9, -22, +mar9,mar18 at presentation in the chronic phase. The dicentric marker 9 was interpreted as representing the usual translocation of 22q11 to 9q34, followed by translocation of the Ph1 chromosome (the deleted 22) to 9p and probable translocation of 9p to the distal long arm of the marker. The patient developed clones containing 2 and 3 copies of the “Ph1-containing” marker 9 concomitant with the metamorphosis of his disease to a more aggressive phase. The second case presented with the karyotype 46,XY,- 9,-22,+two D-group markers. A complex rearrangement of chromosomes 9 and 22 is postulated, with interstitial insertion of either 9p or distal 9q into chromosome 22q11. This patient is still in the chronic phase of his disease 9 mo after presentation. The common denominator in these unusual “masked” cases is the 22q11 breakpoint. The paucity of published reports of duplication of 9q + without concurrent duplication of the Ph1 chromosome, supported by the findings in our first case, leads us to conclude that the amplification of genes on the Ph1 chromosome are more important for the evolution of the abnormal stem cell in CML than the chromosome 9 derivative.
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  • 77
    Publication Date: 1984-04-01
    Description: Thrombin Metz and normal thrombin, resulting from activation of the respective prothrombins by factor Xa in the presence of calcium, phospholipid, and factor Va, were purified by chromatography on sulfopropyl Sephadex. By physicochemical criteria, thrombin Metz is identical to normal thrombin. Its functional properties were investigated in some reactions in which thrombin is classically involved. Thrombin Metz exhibits less than 4% of fibrinogen clotting activity. Both Km and Kcat, determined on S2238, are abnormal. Titration with the high-affinity competitive inhibitor of thrombin, DAPA, shows that fluorescence enhancement of the probe is only 34% in binding to thrombin Metz when compared to that observed in binding to normal thrombin. High-performance liquid chromatography has been used to measure the simultaneous rate of release of fibrinopeptides A and B. A decreased release rate for both fibrinopeptides, more marked for fibrinopeptide B, results in a slow fibrin polymerization, as followed by absorbance at 450 nm. Thrombin Metz is less than 5% as effective as normal thrombin in inducing platelet aggregation. Interaction with antithrombin III is slower than normal when followed by SDS gel electrophoresis and inhibition of the amidolytic activity of thrombin on S2238. This abnormality is not observed in the presence of heparin. However, thrombin Metz binds less tightly to a heparin-Sepharose column, and the direct inhibition of heparin on its activity on S2238 is weaker. From these results, we can predict that the defect in thrombin Metz affects the catalytic site or its vicinity and, jointly or consequently, the region of interaction of thrombin with antithrombin III and heparin.
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  • 78
    Publication Date: 1984-02-01
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  • 79
    Publication Date: 1984-04-01
    Description: Granulocyte-macrophage colony growth depends on the presence of colony- stimulating activity (CSA). Phorbol esters induce concentration- dependent colony formation in the absence of exogenous CSA. We questioned whether phorbol esters mimicked the action of CSA by directly stimulating colony growth, or whether phorbol esters acted indirectly by inducing marrow cells to release CSA. First, after incubating human bone marrow cells with phorbol 12,13-dibutyrate (PDB) for 3 days, we separated PDB from the protein peak of the conditioned medium by Sephadex G-10 gel filtration and tested this peak for the presence of CSA. When diluted 1:10 in the agar colony assay, this material induced 133 +/- 15 colonies/10(5) bone marrow cells. Second, to determine whether bone marrow cells required the continued presence of PDB in order to release CSA, PDB was removed from bone marrow cells by washing, and these cells were reincubated in fresh medium in the absence of PDB. CSA was found in the medium of these cultures; its release was maximal after preincubation of bone marrow cells with 5 X 10(-8) M PDB for 3 days, followed by incubation for 3 days in the absence of PDB. This CSA stimulated granulopoiesis out of proportion to monocytopoiesis, with 85% +/- 17% of the colonies being granulocytic (as indicated by histochemical staining for chloroacetate esterase), and 12% +/- 3% being monocytic (as indicated by nonspecific esterase). Inhibitors of monocyte colony formation, including PGE1, were not present in the medium that contained this CSA. These studies demonstrate that normal human bone marrow cells exposed to PDB release CSA and that this CSA selectively stimulates granulopoiesis in vitro.
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  • 80
    Publication Date: 1984-02-01
    Description: Two patients with chronic myeloid leukemia (CML) showed previously undescribed variants of a “masked” Ph1 abnormality. The first patient had the karyotype 46,XY, + 21, -9, -22, +mar9,mar18 at presentation in the chronic phase. The dicentric marker 9 was interpreted as representing the usual translocation of 22q11 to 9q34, followed by translocation of the Ph1 chromosome (the deleted 22) to 9p and probable translocation of 9p to the distal long arm of the marker. The patient developed clones containing 2 and 3 copies of the “Ph1-containing” marker 9 concomitant with the metamorphosis of his disease to a more aggressive phase. The second case presented with the karyotype 46,XY,- 9,-22,+two D-group markers. A complex rearrangement of chromosomes 9 and 22 is postulated, with interstitial insertion of either 9p or distal 9q into chromosome 22q11. This patient is still in the chronic phase of his disease 9 mo after presentation. The common denominator in these unusual “masked” cases is the 22q11 breakpoint. The paucity of published reports of duplication of 9q + without concurrent duplication of the Ph1 chromosome, supported by the findings in our first case, leads us to conclude that the amplification of genes on the Ph1 chromosome are more important for the evolution of the abnormal stem cell in CML than the chromosome 9 derivative.
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  • 81
    Publication Date: 1984-02-01
    Description: Recent evidence suggests that HLA-A,B antigens present on human platelets, are acquired from plasma. Using hypertonic acid chloroquine (200 mg/ml, pH 5.0, 1 hr, 4 degrees C), we demonstrate elution of most or all HLA-A2 and HLA-B7,40 immunoreactive material from platelets. Corresponding antigens on human lymphocytes were not affected by this treatment. These findings are consistent with the hypothesis that HLA- A,B antigens are adsorbed onto platelet surfaces.
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  • 82
    Publication Date: 1984-02-01
    Description: Washed and gel-filtered human platelets were dose-dependently aggregated by the addition of cationized ferritin (CF). Ca++ and plasma factors were not necessary to induce the aggregation. Immediately after the addition of CF, CF particles were attached to the surface of platelets that showed discoid form, as observed electron microscopically. Some platelets were connected to each other through the CF particles located on their membranes. After the addition of CF, the following was observed: at 15 sec after, platelets showed a round form and were aggregated to each other; at 3 min after, centralization of granules was clearly seen and the aggregates increased their size during the time course; at 3–5 min after, the CF-connected aggregates were found locally. Around the aggregates, other platelets were aggregated, though not through the membrane-located CF. Observing with a lumiaggregometer, the aggregation showed a biphasic curve associated with adenosine triphosphate (ATP) release. The second part of aggregation curve was inhibited by PGI2, PGE1, aspirin, N- ethylmaleimide, and apyrase. The first part of the aggregation curve was inhibited only by heparin. Neuraminidase treatment also inhibited the aggregation dose-dependently. These findings suggest that neutralization of the platelet surface negative charge by a positively charged macromolecule can trigger platelet aggregation, which is followed by the release reaction.
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  • 83
    Publication Date: 1984-02-01
    Description: The relation between platelet buoyant density and beta-thromboglobulin (beta-TG), a marker for platelet alpha-granule content, was assessed by three independent approaches. (1) Platelets were separated on iso- osmolar discontinuous Stractan density gradients into five fractions, ranging in density from 1.061 g/ml to 1.091 g/ml (20 degrees C). The beta-TG content (mean +/- SD, n = 17) increased with the platelet density from 27.8 +/- 8.6 micrograms beta-TG/10(9) cells (20% less- dense platelets) up to 65.6 +/- 15.5 micrograms beta-TG/10(9) cells (15% most-dense platelets). (2) Activation of platelets in platelet- rich plasma with thrombin, adenosine diphosphate, collagen, or epinephrine resulted in a decreased density of the platelets. This was only seen when there was simultaneous secretion of beta-TG. (3) The less-dense and the more-dense platelet fractions, after isolation by density gradient centrifugation, were separately treated with thrombin. After complete degranulation, the density distribution of the originally less-dense and more-dense platelets were identical and were much narrower than the density distribution of resting platelets.
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  • 84
    Publication Date: 1984-02-01
    Description: Previous reports have shown that serum beta-2-microglobulin (S beta2M) is a reliable marker of presenting tumor mass, response to chemotherapy, and prognosis of patients with multiple myeloma (MM). In order to more thoroughly evaluate the optimal use of S beta2M in plasma cell dyscrasias (PCD), S beta2M levels were serially measured in 160 patients with MM, in comparison with 37 normal controls (NC) and 28 patients with monoclonal gammopathy of undetermined significance (MGUS). In MGUS, S beta2M did not differ significantly from that of NC, but was significantly lower than that of MM (p less than 0.001), including low cell mass MM (p less than 0.02). In MM, S beta 2M was highly correlated with the total body burden of myeloma cells as derived from the staging of Durie and Salmon, both at diagnosis and in remission (residual tumor mass) (p less than 0.001). During the plateau phase, S beta 2M remained very stable and was always within the normal range for patients with greater than or equal to 75% tumor regression. The most striking finding was that S beta 2M gave an extremely reliable fit for survival prediction at (1) diagnosis, (2) remission, and (3) early relapse, with higher S beta 2M levels in each instance being in favor of poorer prognosis. We conclude that S beta 2M is an extremely useful marker in initial stratification and follow-up of patients with MM.
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  • 85
    Publication Date: 1984-02-01
    Description: Human neutrophil elastase is thought to play an important role in connective tissue destruction in diseases such as emphysema and arthritis. In this article, it is demonstrated that the elastase activity of mature human peripheral blood neutrophils can be rapidly increased in vitro by treatment of the cells with lipopolysaccharide from E. coli and that this increase is inhibited by corticosteroid pretreatment of the cells and by inhibitors of protein synthesis. Alterations in intracellular enzyme content of the mature polymorph in response to bacterial products or other stimuli may be important for amplification of the inflammatory response.
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  • 86
    Publication Date: 1984-02-01
    Description: Chronic idiopathic thrombocytopenic purpura (ITP) is caused by an antibody reactive with platelet-associated antigens. The present studies provide direct evidence that some patients with chronic ITP have autoantibodies against the platelet glycoprotein (GP) IIb/IIIa complex. Microtiter wells, coated with a monoclonal antibody (2G12) specific for GPIIb/GPIIIa were reacted with GPIIb/GPIIIa contained in a platelet extract. Control wells containing the same antibody were reacted with a cell extract containing no GPIIb/GPIIIa. After washing, the wells were reacted with patient or control plasma, and IgG binding was detected using 125I-Fab2-anti-human IgG. Assay values were expressed as binding ratios (cpm GPIIb/GPIIIa wells/cpm control wells). Plasma from 5 of 56 patients with chronic ITP had ratios (1.36–3.14) greater than 3 standard deviations above the mean (+/- SD) of control plasmas--0.93 +/- 0.12. Elevated values were also noted in two patients with anti-P1A1 antibody (ratios greater than 30) and in one patient with Hodgkin's disease and an ITP-like syndrome (ratio 1.53). Normal values were noted in 34 patients with a variety of immune and nonimmune diseases. Plasma from two of the positive ITP patients was reacted with 125I-surface-labeled platelets and, after solubilization, the IgG and bound antigen were precipitated with Staph-A. Autoradiographs from SDS- PAGE electrophoresis of the Staph-A-bound proteins shows two radioactive bands consistent in size with GPIIb and GPIIIa.
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  • 87
    Publication Date: 1980-03-01
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  • 88
    Publication Date: 1980-03-01
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  • 89
    Publication Date: 1980-03-01
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  • 90
    Publication Date: 1980-01-01
    Description: Sephacryl beads containing an immobilized aminopropylcobalamin- transcobalamin-II complex serve as foci for the adherence of L1210 murine leukemia cells. Bead-cell interaction does not occur when (A) nonderivatized beads are used; (B) transcobalamin-II is omitted or presaturated with cyanocobalamin in the preparation of the bead complex; (C) intrinsic factor replaces transcobalamin-II; and (D) the complex is removed from beads by photolysis. These observations suggest that adherence results from the ability of transcobalamin-II to form a bridge between immobilized cobalamin on the bead and receptors in the plasma membrane of the cell.
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  • 91
    Publication Date: 1980-02-01
    Description: An immunohistochemical procedure for the detection of immunoglobulin G adherent to platelets is described. The peroxidase anti-peroxidase method is used to detect antibody activity directed against platelets from normal donors in the sera from 305 individuals. These subjects were divided into three groups: group 1, patients referred for tissue typing; group 2, healthy normal females; group 3, healthy normal males. In group 1, 28% of the sera were found to be positive; in most of these a history of prior transfusions was obtained. In group 2, 7.4% were found to be positive, most having previous pregnancies. Only 1% were found to be positive in group 3, and no reason for presensitization was found. Results from the indirect immunofluorescence technique served as a control and as a means to compare the sensitivity. Under the conditions chosen, the peroxidase anti-peroxidase test was two to eight times more sensitive than the immunofluorescence technique. Specificity of the peroxidase anti-peroxidase technique was demonstrated using a monospecific anti-PLA1 antiserum. It is concluded that the peroxidase anti-peroxidase slide technique may be a useful tool in the study of platelet-related immunophenomena.
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  • 92
    Publication Date: 1980-02-01
    Description: Membrane markers expressed by a transplantable granulocytic leukemia induced in inbred strain 13 guinea pigs by N-nitroso-N-butylurea have been investigated by serologic and immunochemical methods. Although the leukemic myeloblasts have no detectable surface immunoglobulin or Fc receptors, they have been found to synthesize and express membrane antigens encoded for by the I-region of the major histocompatibility complex. Despite the presence of Ia antigens, these cells do not stimulate allogeneic T lymphocytes in the mixed lymphocyte reaction nor are they able to present soluble antigen to immune T cells. The presence of Ia antigens on immature myeloid cells suggests that these proteins may be important in cellular functions beyond those identified in the cellular immune system.
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  • 93
    Publication Date: 1980-02-01
    Description: Urinary ferritin levels were measured by a “2-site” immunoradiometric assay in normal volunteers and in patients with various hematologic disorders. The mean urinary ferritin concentration in normal subjects averaged 2.2 microgram/liter, only 3% of the serum ferritin level. Elevated urinary ferritin levels averaging 45 microgram/liter were observed in patients with hematologic malignancies, but there was a proportional increase in serum ferritin so that the urinary level still averaged only 7% of the serum value. The highest urinary ferritin values (mean 170 microgram/liter) were associated with chronic hemolytic anemia, and in these patients, urinary ferritin rose disproportionately in relation to the serum, averaging 82% of it. This higher urinary level apparently reflects increased ferritin in renal tubular cells due to glomerular filtration of unbound hemoglobin, a mechanism that is supported by a highly significant correlation between urinary ferritin and serum haptoglobin levels. In normal subjects and in patients with malignancy, the source of urinary ferritin appears different, since a highly significant correlation was observed between urinary ferritin and reticuloendothelial iron stores as measured by serum ferritin or total iron-binding capacity. In this setting, the most likely source of urinary ferritin is the iron contained in renal tubular cells, which is apparently in equilibrium with body iron stores.
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  • 94
    Publication Date: 1980-01-01
    Description: A new assay for the long-term functional capacity of hemopoietic stem cells is reported. Stem cell function in each donor of a particular genotype is assayed by mixing its marrow cells with a constant number of marrow cells from a donor with distinguishable hemoglobin and measuring the relative ability of each donor to populate stem-cell- depleted recipients. For example, cells from many different B6 donors may be assayed by mixing them with a constant number of WBB6F1 cells from a single pool and injecting them into irradiated WBB6F1 recipients. As the ratio of B6 to WBB6F1 marrow cells increases from 0:1 to 3:1 the percentage of B6 hemoglobin increases in a linear fashion. This is also found with WB and WBB6F1 or CBA and B6CBAF1 mixtures. Correlation coefficients between the percentage of hemoglobin of one donor type and the ratio of cells in the mixture of that type ranged from 0.78 to 0.98 in single experiments, and were 0.68 and 0.75 using data pooled from several experiments.
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  • 95
    Publication Date: 1980-01-01
    Description: Erythrocytes from heterozygous carriers of the high oxygen affinity mutant hemoglobin, Hb Wood, demonstrate lower rates of methemoglobin reduction than normal human red cells when incubated in the in vitro system of Beutler and Baluda. The rate of methemoglobin reduction in red cells from an individual who is heterozygous for both NADH- methoglobin reductase deficiency and Hb Wood shows the combined effects of the two mutations.
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  • 96
    Publication Date: 1980-02-01
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  • 97
    Publication Date: 1980-01-01
    Description: Leukemic cells from 20 patients with chronic lymphocytic leukemia (CLL) and 60 patients with acute lymphocytic leukemia (ALL) were studied for T- and B-lymphocyte cell surface membrane markers. B-cell markers included surface membrane immunoglobulin, erythrocyte-antibody complement rosette formation, and B-cell (a-like or HLA-DR) antigens detected by a B-cell antiserum. T-cell markers included spontaneous sheep red blood cell rosette formation and a cytotoxic reaction to a specific T-cell antiserum. Seven patients with CLL and two with ALL had dual B and T markers. We propose that dual B- and T-cell markers are more common in CLL and ALL patients than previously reported. With newer and more sensitive tests for identification of B and T cells, this observation may be recognized more frequently.
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  • 98
    Publication Date: 1980-01-01
    Description: A patient with multiple myeloma developed periodic blood neutropenia (periodicity of 15–25 days) after 3 yr of intermittent treatment with cytotoxic agents. Peaks of serum colony-stimulating activity (CSA) level coincided with valleys of blood neutrophils. Fraction of marrow neutrophils in the multiplicative pool was high during blood neutrophil valleys and low during neutrophil peaks. In contrast, the maturation storage pool exhibited the reverse pattern. An increased fraction of marrow neutrophilic cells in the multiplicative pool was in active proliferation during a blood neutrophil valley and a decreased fraction during a blood neutrophil peak. These findings suggest that the marrow granulopoiesis was regulated through CSA. The defect causing the periodicity was probably related to the reduced number of neutrophils in the marrow maturation storage pool, which in turn may be related to a reduced and/or defective granulocytic stem cell pool size consequent to the long-term administration of cytotoxic drugs and/or infiltration of the marrow by myeloma cells.
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  • 99
    Publication Date: 2008-11-15
    Description: PU.1, IKAROS, E2A, EBF, and PAX5 comprise a transcriptional network that orchestrates B-cell lineage specification, commitment, and differentiation. Here we identify interferon regulatory factor 8 (IRF8) as another component of this complex, and show that it also modulates lineage choice by hematopoietic stem cells (HSCs). IRF8 binds directly to an IRF8/Ets consensus sequence located in promoter regions of Sfpi1 and Ebf1, which encode PU.1 and EBF, respectively, and is associated with transcriptional repression of Sfpi1 and transcriptional activation of Ebf1. Bone marrows of IRF8 knockout mice (IRF8−/−) had significantly reduced numbers of pre-pro-B cells and increased numbers of myeloid cells. Although HSCs of IRF8−/− mice failed to differentiate to B220+ B-lineage cells in vitro, the defect could be rescued by transfecting HSCs with wild-type but not with a signaling-deficient IRF8 mutant. In contrast, overexpression of IRF8 in HSC-differentiated progenitor cells resulted in growth inhibition and apoptosis. We also found that IRF8 was expressed at higher levels in pre-pro-B cells than more mature B cells in wild-type mice. Together, these results indicate that IRF8 modulates lineage choice by HSCs and is part of the transcriptional network governing B-cell lineage specification, commitment, and differentiation.
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  • 100
    Publication Date: 2005-09-01
    Description: Heme oxygenase-1 (HO-1) is an intracellular enzyme that degrades heme and inhibits immune responses and inflammation in vivo. In most cell types, HO-1 is inducible by inflammatory stimuli and oxidative stress. Here we demonstrate that human monocyte-derived immature dendritic cells (iDCs) and several but not all freshly isolated rat splenic DC subsets and rat bone marrow-derived iDCs, spontaneously express HO-1. HO-1 expression drastically decreases during human and rat DC maturation induced in vitro. In human tissues, iDCs also express HO-1, whereas mature DCs do not. Induction of HO-1 expression with cobalt protoporphyrin (CoPP) in human and rat DCs inhibits lipopolysaccharide (LPS)-induced phenotypic maturation and secretion of proinflammatory cytokines, resulting in the inhibition of alloreactive T-cell proliferation. CoPP-treated DCs, however, retain the ability to produce the anti-inflammatory cytokine interleukin 10 (IL-10). Reactive oxygen species induced by LPS in DCs were inhibited by induction of HO-1. In conclusion, we identify, for the first time, the capacity of HO-1 to block maturation of DCs and to inhibit proinflammatory and allogeneic immune responses while preserving IL-10 production. This novel immune function for HO-1 may be of interest for the inhibition of immune responses in autoimmune diseases, transplantation, and other conditions involving activation of the immune system. (Blood. 2005;106:1694-1702)
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