bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automated quantitation of cell density distribution and hyperdense cell fraction in RBC disorders
Authors: Mohandas N , Johnson A , Wyatt J , Croisille L , Reeves J , Tycko D , Groner W 
Published: October 2019

Abstract
An altered state of cell hydration is a hallmark of a number of RBC disorders. The two parameters most often used to characterize the state of cell hydration are (a) the complete cell density distribution profile, and (b) the fraction of cells with densities greater than a defined value. Buoyant density cell fractionation with a variety of polymers has long been the preferred method for obtaining data on cell density distribution. Although this method provides accurate and quantitative information on the state of RBC hydration, its applicability has been limited due to the time-consuming experimental procedure involved in generating the data. A recently developed light- scattering method has been used in the present study to quantitate RBC density distribution. This new method accurately quantitates both the cell density distribution profile and the fraction of dense, dehydrated cells in various RBC disorders. The ability of the automated method to generate this information rapidly makes possible objective testing of different hypotheses concerning the contributions of cell hydration and dehydration to the pathophysiology of various RBC disorders.
Erythropoietin alone induces erythroid burst formation by human embryonic but not adult BFU-E in unicellular serum-free culture [see comments]
Authors: Valtieri M , Gabbianelli M , Pelosi E , Bassano E , Petti S , Russo G , Testa U , Peschle C 
Published: October 2019

Abstract
Erythroid progenitors (BFU-E) from adult human peripheral blood generate erythroid bursts in semisolid culture supplemented with at least two growth factors, ie, erythropoietin (Ep) and interleukin-3 (IL- 3) or granulocyte-macrophage colony-stimulating factor (GM-CSF). We have analyzed the hematopoietin(s) requirement of human embryonic BFU- E, as compared to that of adult peripheral blood progenitors: This was basically evaluated in fetal calf serum-free (FCS-) methylcellulose culture of partially or highly purified progenitors treated with human recombinant hemopoietins. At a low seeding concentration (2 x 10(3) cells/dish) purified embryonic BFU-E generated erythroid bursts when treated only with Ep: Further addition of IL-3 or GM-CSF had no effect on BFU-E cloning efficiency, although the size of bursts was increased in a dose-dependent manner, particularly with IL-3. At a similar seeding concentration (ie, 10(3) cells/dish), purified adult BFU-E efficiently generated erythroid bursts in the presence of Ep and GM-CSF or IL-3, while only few small erythroid colonies were observed in the presence of Ep alone. In a final series of experiments, unicellular FCS- cultures of purified embryonic BFU-E gave rise to erythroid bursts in the presence of Ep alone. Furthermore, the cloning efficiency induced by Ep was unmodified by further addition of GM-CSF or IL-3. Unicellular FCS- cultures of highly purified adult peripheral blood progenitors generated no erythroid bursts in the presence of Ep alone. The addition of GM-CSF or IL-3 was required to generate BFU-E colonies. These studies indicate that in human embryonic life, BFU-E require only Ep for efficient erythroid burst formation, while IL-3 and GM-CSF essentially enhance the proliferation of early erythropoietic precursors.
NADPH production by the malarial parasite Plasmodium falciparum
Authors: Vander Jagt DL , Hunsaker LA , Kibirige M , Campos NM 
Published: October 2019

Abstract
Two enzymes from Plasmodium falciparum that catalyze the formation of NADPH have been partially purified and characterized. Glutamate dehydrogenase (GDH), molecular mass 230 Kd, pH optimum 7.0, is capable of producing NADPH under optimum conditions at about 10% of the capacity of the host erythrocyte. This capacity increases slightly during the developmental cycle of the parasite. NADP-specific isocitrate dehydrogenase (IDH), molecular mass 80 Kd, pH optimum 7.5, is capable of producing NADPH at 20% to 60% of the capacity of the host cell, depending on the developmental stage of the parasite. Increasing IDH activity is observed as the parasite matures. GDH and IDH provide the parasite with NADPH-generating abilities that compare favorably with the host cell.
Reticulocytes. I. Isolation and in vitro maturation of synchronized populations
Authors: Noble NA , Xu QP , Ward JH 
Published: October 2019

Abstract
Studies of reticulocyte maturation have been limited by the inability to obtain pure populations of age-synchronized reticulocytes and by the absence of well-defined methods for the maturation of reticulocytes in vitro. Many of these problems were overcome using temporary suppression of erythropoiesis with thiamphenicol and phlebotomy resulting in a highly reproducible reticulocyte response, Percoll density gradient separation of cells yielding essentially pure populations of age- synchronized reticulocytes, and liquid culture techniques where cell lysis is minimal. The system allows reproducible study of well-defined cohorts of reticulocytes as they mature into erythrocytes. During in vitro maturation we serially monitored changes in reticulocyte count, glucose consumption, 125I-transferrin binding, fluorescein (FITC)- labeled transferrin binding, the activities of four erythrocyte enzymes (glucose-6-phosphate dehydrogenase, pyruvate kinase, phosphofructokinase, and lactate dehydrogenase) and the appearance of cells on scanning electron microscopy. These variables changed at different rates suggesting that multiple mechanisms underlie these maturational events. Transferrin binding and reticulocyte count decreased most rapidly and reached values near zero after three to four days in culture. The four enzyme activities decreased much more slowly, and only two reached pretreatment values after seven days in culture. In contrast to the findings of others, scanning electron microscopy suggested that cells do not assume the normal biconcave shape in this system. The methods described make it feasible to study the process of reticulocyte maturation in vitro. The data presented represent a first step in the study of the coordination and interrelationships of various maturational processes.
Developmental regulation of erythropoiesis by hematopoietic growth factors: analysis on populations of BFU-E from bone marrow, peripheral blood, and fetal liver
Authors: Emerson SG , Thomas S , Ferrara JL , Greenstein JL 
Published: October 2019

Abstract
Fetal hematopoiesis is characterized by expanding erythropoiesis to support a continuously increasing RBC mass. To explore the basis for this anabolic, nonhomeostatic erythropoiesis, the proliferative effect of recombinant hematopoietic growth factors on highly enriched hematopoietic progenitor cells from fetal and adult tissues were compared. Fetal hepatic BFU-E, unlike adult bone marrow (BM) or peripheral blood (PB) BFU-E, were capable of proliferating in response to erythropoietin in the absence of added GM colony-stimulating factor (GM-CSF) or interleukin-3 (IL-3), and erythropoietin (Epo) directly stimulated the expansion of the fetal BFU-E pool in suspension culture. A murine monoclonal antibody (MoAb), Ep 3, was raised against enriched fetal liver progenitor cells, which detected all fetal BFU-E and which reacted with the erythropoietin-responsive, GM-CSF/IL-3-independent fraction of adult BM BFU-E and CFU-E. All adult PB BFU-E were Ep 3- but became Ep 3+ after stimulation with GM-CSF or IL-3. These data indicate that Epo plays a unique role in fetal hepatic erythropoiesis, stimulating proliferation of immature BFU-E in addition to promoting terminal differentiation of later erythroid progenitor cells. In addition, these results demonstrate a MoAb which detects all erythropoietin-responsive progenitor cells and distinguishes the BFU-E compartments in adult BM and PB.
Feline parvovirus propagates in cat bone marrow cultures and inhibits hematopoietic colony formation in vitro
Authors: Kurtzman GJ , Platanias L , Lustig L , Frickhofen N , Young NS 
Published: October 2019

Abstract
Feline parvovirus (FPV) causes leukopenia in naturally infected cats. We investigated the mechanism of hematopoietic depression by this virus in feline bone marrow cultured in vitro. In suspension cultures we demonstrated FPV propagation and replication using DNA molecular hybridization. Viral RNA and DNA were observed by in situ hybridization in about 10% of marrow cells at day 3. Granulocytes and their precursors were virtually absent from infected cultures after six days. Infected cells showed viral capsid protein predominantly in nuclei by immunofluorescence. In clonal assays, FPV most efficiently inhibited hematopoietic colony formation by myeloid progenitor cells (CFU-GM), but erythroid colony formation (BFU-E and CFU-E-derived) was also depressed in the presence of virus. Inhibition of colony formation could be abrogated by physical inactivation of the virus or preincubation with specific neutralizing antibodies. Recombinant human colony stimulating factors GM-CSF and G-CSF supported feline myelopoiesis in progenitor assays, and FPV completely inhibited factor dependent colony formation.
Prognosis of aggressive lymphomas: a study of five prognostic models with patients included in the LNH-84 regimen
Authors: Coiffier B , Lepage E 
Published: October 2019

Abstract
Four prognostic models described for aggressive malignant lymphomas and the classical Ann Arbor staging system were used to compare the survival of 737 patients treated with the LNH-84 regimen. The aim of the study was to determine the optimal prognostic system at the time of diagnosis. Three institutions have described these models after multivariate analyses: the Dana Farber Cancer Institute (DFCI1 and DFCI2), the MD Anderson Hospital (MDAH), and the Memorial Sloan- Kettering Cancer Center (MSKCC). The models were constructed with the following variables: performance status, LDH level, and tumor extension. The latter is the most difficult to assess: it was considered as the number of extranodal sites and the diameter of the largest mass in DFCI1, stage and the diameter of the largest mass in DFCI2, the number of extranodal and extensive nodal sites in MDAH, and the number of nodal sites and their localization in MSKCC. Univariate studies with LNH-84 regimen patients showed all these variables to have major prognostic significance (logrank tests: P less than 10(-4)). All five prognostic systems divided patients into three subgroups: good, intermediate, and poor prognosis. Logrank analyses of survival showed highly significant differences (X2 greater than 90 and P less than 10(- 6)) between the subgroups. No gross difference was found between the models, and none was better than the others. A new, internationally accepted prognostic system for the expression and comparison of treatment results in aggressive malignant lymphomas should include major univariate prognostic parameters and must be reliable and easy to use in clinical practice. Until such time, stage or LDH level are the best alternatives.
Flow cytometric analysis of megakaryocytes from patients with abnormal platelet counts
Authors: Tomer A , Friese P , Conklin R , Bales W , Archer L , Harker LA , Burstein SA 
Published: October 2019

Abstract
Megakaryocytes (MKs) from 40 patients with quantitative platelet disorders and 19 normal volunteers were analyzed by flow cytometry for size, fine cell internal structure and granularity, membrane expression of the glycoprotein (GP) IIb/IIIa complex, and for ploidy distribution. Analysis was performed on unfractionated minimally manipulated marrows obtained from routine bone marrow aspirates. MKs were labeled with a fluorescent lineage-specific monoclonal antibody to the GPIIb/IIIa complex followed by DNA staining with propidium iodide. Eight hundred to 3,000 MKs were analyzed in each sample. The modal ploidy distribution in normals was 16N, comprising about half of the megakaryocytic population, with 22.6% of the cells less than or equal to 8N and 22.0% greater than or equal to 32N. Twelve thrombocytopenic patients with decreased marrow MKs on biopsy (mean platelet count [MPC] 44,600/microliters) showed an increase in low ploidy cells with 53.2% less than or equal to 8N (P less than .01); cell size was reduced in three patients when compared to normal cells of identical ploidy (P less than .05). Eight thrombocytopenic patients with enhanced platelet destruction (with normal or increased MKs on biopsy and shortened platelet survival; MPC 41,400/microliters) showed an increased proportion of high ploidy cells greater than or equal to 32N to 39.2% (P less than .01). Increased cell size and granularity were found in four of these patients (P less than .05). Six patients with thrombocytopenia secondary to multiple mechanisms affecting both platelet production and destruction (MPC 66,700/microliters) showed no shift in ploidy. Four patients with primary thrombocytosis (two with thrombocythemia and two with polycythemia vera; MPC 822,500/microliters) showed a marked shift toward high ploidy cells with 42.3% greater than or equal to 32N and 7.6% greater than or equal to 64N cells (P less than .01). The shift was accompanied by a marked increase in cell size and granularity in the patients with thrombocythemia. Ten patients with thrombocytosis secondary to chronic blood loss, malignant or inflammatory disorders (MPC 714,000/microliters), showed variable distributions with four patients exhibiting a shift in ploidy to the right similar to that found in the patients with increased platelet destruction. Based upon the present data, flow cytometric ploidy distribution may be diagnostically useful in thrombocytopenic patients by discriminating between disorders of platelet production and destruction.
An antifibrin monoclonal antibody useful in immunoscintigraphic detection of thrombi
Authors: Wasser MN , Koppert PW , Arndt JW , Emeis JJ , Feitsma RI , Pauwels EK , Nieuwenhuizen W 
Published: October 2019

Abstract
Balb/c mice were immunized with human plasmin-generated fibrinogen degradation product Y. Spleen cells were fused with P3X63-Ag8.653 myeloma cells. A clone (Y22) was found that produces monoclonal antibodies (MoAbs) with a strong reactivity with human fibrin and only a weak reactivity with fibrinogen in an enzyme immunoassay (EIA). Y22 also reacts with fibrin of rabbits, rats, sheep, and dogs. The antibodies are of the IgG1 kappa-type and appear to be directed against a conformation-dependent epitope in the D-domain of fibrin. Experiments with 99mTc-labeled Y22 in vitro show that Y22 binds rapidly to forming clots. 99mTc-Y22 also binds to preformed plasma clots in a plasma milieu, even in the presence of high concentrations of heparin. Clot localization experiments in rabbits and rats confirm the high fibrin specificity and the potential of 99mTc-Y22 for thrombus imaging in vivo.
B-cell dysfunction following human bone marrow transplantation: functional-phenotypic dissociation in the early posttransplant period
Authors: Kagan JM , Champlin RE , Saxon A 
Published: October 2019

Abstract
We investigated the defect in humoral immunity that occurs following bone marrow transplantation (BMT). B cells from BMT recipients were tested for their ability to undergo the sequential steps of activation (RNA synthesis on stimulation with anti-mu or PMA), proliferation (DNA synthesis on stimulation with anti-mu plus B cell growth factor [BCGF], phorbol myristate acetate [PMA], or Staphylococcus aureus Cowan I [SAC] strain bacteria) and differentiation (Ig synthesis stimulated by T cell replacing factor [TRF]). B-cell maturation-associated cell surface markers were simultaneously investigated. “Early” (less than 10 months) posttransplant patients demonstrated defective B-cell activation and also failed to undergo normal proliferation and differentiation. Despite their functional impairment, the early patients' B cells displayed an “activated” phenotype with increased proportions of B cells displaying CD23 (a BCGF receptor) and decreased proportions of Leu 8+ B cells. Furthermore, these patients were uniquely distinguished by the fact that their B cells only weakly (if at all) expressed the CD19 antigen. In contrast, B cells from “late” patients (greater than or equal to 10 months post-BMT) activated and proliferated normally and displayed a normal cell surface phenotype, yet were unable to differentiate to high rate Ig secretion with TRF. Our results suggest a phenotype/function dissociation in early posttransplant period. With time, B cells in BMT patients acquire a normal surface phenotype and can activate and proliferate normally, yet still demonstrate a block in terminal differentiation.
Thrombin-induced increase in surface expression of epitopes on platelet membrane glycoprotein IIb/IIIa complex and GMP-140 is a function of platelet age
Authors: Savage B , Hunter CS , Harker LA , Woods VL Jr , Hanson SR 
Published: October 2019

Abstract
Platelets are heterogeneous in the content of membrane glycoprotein (GP)IIb/IIIa complex. To determine whether this heterogeneity is related to changes associated with platelet aging in the circulation, newly released platelets, obtained during recovery from nonimmune- mediated acute experimental thrombocytopenia in baboons, were studied. Monoclonal antibody (MoAb) binding to epitopes expressed on GPIIb/IIIa complex (LJ-CP8), GMP-140 (S12), and GPIa/IIa (12F1) was measured on control platelets (comprising platelets with a normal age distribution; mean age 60 to 72 hours) and newly formed platelets (mean age 12 hours), both in the resting state and after thrombin stimulation. Whereas LJ-CP8 binding to resting control platelets increased by 34% upon stimulation by gamma-thrombin from 30,885 +/- 1,171 to 41,458 +/- 1,311 molecules/platelet at saturating concentrations of antibody, LJ- CP8 binding to resting young platelets did not increase significantly upon thrombin stimulation (31,878 +/- 3,330 and 33,791 +/- 3,486 molecules/platelet, respectively). Similarly, binding of antibody S12 in response to maximal thrombin stimulation was reduced by 42% from 10,246 +/- 834 molecules/platelet at saturating concentrations of S12 for control platelets to 5,971 +/- 665 molecules/platelet for young platelets (P = .001). S12 binding to unstimulated platelets was less than 10% of the binding observed after thrombin stimulation at all concentrations of S12 for both control and young platelets. However, maximal binding of antibody 12F1 to resting control platelets did not differ significantly from that observed with resting young platelets (2,926 +/- 167 and 2,857 +/- 208 molecules/platelet, respectively), and 12F1 binding was unchanged after thrombin stimulation for both control and young platelets. We conclude that the thrombin-induced increase in the expression of epitopes on platelet membrane GPIIb/IIIa complex and GMP-140 is a function of platelet age.
Elevated serum-soluble interleukin-2 receptor (Tac antigen) levels in chronic myelogenous leukemia patients with blastic crisis
Authors: Motoi T , Uchiyama T , Hori T , Itoh K , Uchino H , Ueda R 
Published: October 2019

Abstract
We examined the expression of cell-surface interleukin-2 (IL-2) receptor (Tac antigen) on peripheral blood leukemic cells and measured soluble IL-2 receptor p55(alpha) chain (sIL-2R) levels in sera from chronic myelogenous leukemia (CML) patients with blastic crisis. Flow cytofluorometric analysis performed by dual immunofluorescence in three cases demonstrated coexpression of Tac antigen with myeloid (CD13, CD14, or CD33) or lymphoid (CD10) antigen on significant proportions of peripheral blood leukemic cells. Radiolabeled IL-2-binding assay demonstrated the specific IL-2 binding sites in three cases examined. The exogenous IL-2, however, failed to induce proliferative response. A myeloid cell line, Yut-K3, established from peripheral blood leukemic cells from a CML patient with blastic crisis, also expressed cell- surface Tac antigen and CD13 concurrently. SIL-2R assay showed that Yut- K3 released a detectable amount of sIL-2R in its culture supernatant. The serum sIL-2R levels were significantly elevated (range: 2,580 to 172,000 U/mL) in 12 CML patients with blastic crisis and were slightly elevated in ten patients in chronic phase (range: 250 to 820 U/mL) and in three in accelerated phase (range: 790 to 1,305 U/mL) compared with those in 24 normal controls (range: 70 to 695 U/mL, P less than .01). These results indicated that the leukemic cells from CML patients with blastic crisis expressed and released IL-2 receptor (Tac antigen). Longitudinal studies performed in three cases of CML with blastic crisis showed that the change of serum sIL-2R level was closely associated with that of the number of peripheral blood leukocytes and blasts, the percentage of blasts and serum LDH levels, also suggesting that the serum sIL-2R level is a useful clinical indicator of the leukemic cell burden in vivo.
Platelet transfusion therapy for alloimmunized patients: selective mismatching for HLA B12, an antigen with variable expression on platelets
Authors: Schiffer CA , O'Connell B , Lee EJ 
Published: October 2019

Abstract
There can be wide variation in the expression of the HLA B12 antigen and its “splits,” B44 and 45, on the platelets and lymphocytes from the same individual. One hundred sixty-two single donor platelet transfusions mismatched only for this antigen group were administered to 54 alloimmunized patients who were refractory to random donor platelets. Satisfactory increments (one-hour post-transfusion corrected- count increment [CCI] greater than 7,500) were seen following 111/162 transfusions (69%). In 31 patients (57%), all transfusions (n = 85) produced CCI greater than 7,500, and 76% of patients received some transfusions that were satisfactory. Of note is that ten patients had excellent increments despite either preformed lymphocytotoxic antibody against the mismatched antigen or positive lymphocytotoxic cross- matches with the donor. In contrast, poor increments were seen in ten recipients under similar circumstances, implying disparities in antigen expression on the platelets and lymphocytes of different donors. There was no obvious pattern of other donor HLA antigens which could be correlated with these differences. The HLA B12 antigen group is relatively common (found in approximately 25% of the population), and these data indicate that selective mismatching for these antigens can be an effective donor-selection strategy to increase the number of donors for alloimmunized recipients.