bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synergistic effects of butyrate on platelet responses to arachidonate, A23187, PGE1, and forskolin
Authors: Tandon NN , Tralka TS , Jamieson GA 
Published: October 2019

Abstract
With eukaryotic cells, butyrate is known to induce a series of morphological and biochemical changes that mimic cellular differentiation. With platelets, we have found that butyrate (10 mmol/L) caused an approximately threefold increase in sensitivity to calcium ionophore A23187 and arachidonate. Maximum aggregation was observed at agonist concentrations of 3 mumol/L and 170 mumol/L, respectively, as compared with required concentrations of 10 mumol/L and 400 mumol/L in the absence of butyrate. Similar effects were seen with isobutyric acid, and about one-half the effect was shown with valerate and caproate, but lower homologues showed no synergistic effect. No ultrastructural changes were observed in platelets incubated with butyrate, and the aggregation effects were reversible and returned to normal on removal of butyrate. Membrane fluidity was unchanged by butyrate as measured by changes in the fluorescence depolarization of diphenylhexatriene. Butyrate caused a 60% to 70% increase in the uptake of 3H-arachidonate. Butyrate also potentiated the inhibition of platelet function by prostaglandin E1 and forskolin and uptake of 3H- forskolin was increased approximately 20%. In contrast, platelet response to other agonists (ADP, epinephrine, collagen, thrombin, and platelet-activating factor) was essentially unaffected by butyrate. These results suggest that butyrate may increase the uptake of certain hydophobic agonists and antagonists by platelets. Similar mechanisms for uptake of endogenous effectors may explain the response of eukaryotic cells to butyrate in culture.
Altered stem cell (CFU-S) function following infection of hematopoietic cells with a virus carrying V-src
Authors: Boettiger D , Dexter TM 
Published: October 2019

Abstract
Long-term murine bone marrow cultures were used to support the growth and development of hematopoietic cells. After hematopoiesis was established, the cultures were infected with a recombinant murine amphotropic virus carrying the avian sarcoma virus src gene and the CFU- S kinetics were examined. The CFU-S from the src-infected cultures displayed a reduced seeding efficiency in the standard spleen colony assay. The self-renewal capacity of these CFU-S was tested by their ability to reestablish hematopoiesis when serially transplanted on irradiated bone marrow cultures and by serial passage in spleens of irradiated mice. In both tests, cells from the src-infected cultures exhibited an enhanced ability to sustain a high level of self-renewal. The other property of stem cells which may be measured is the probability of self-renewal at each cell division which dictates the distribution between stem cells and differentiated type progeny. CFU-S from the src-infected cultures had higher average probabilities of self- renewal and therefore reduced differentiation. These differences suggest that expression of src had indirectly or directly altered the normal differentiation program of the stem cells.
Effect of leukocyte antibodies and HLA matching on the intravascular recovery, survival, and tissue localization of 111-indium granulocytes
Authors: McCullough J , Clay M , Hurd D , Richards K , Ludvigsen C , Forstrom L 
Published: October 2019

Abstract
The effect of leukocyte antibodies detected under different conditions on the fate in vivo of granulocytes was studied using 111-indium- labeled granulocytes. Sera from patients were tested by granulocyte agglutination (GA), granulocytotoxicity (GC), granulocyte immunofluorescence (GIF), lymphocytotoxicity (LC), and antibody- dependent lymphocyte-mediated granulocytotoxicity. Granulocytes from donors to be studied were labeled with 111-indium and injected. Then the intravascular recovery and survival or tissue localization was determined in 93 studies. Antibodies detected by granulocyte agglutination were associated with a significant reduction in recovery (6.7% v 30.8% in controls; P less than .001) and t1/2 (0.3 hours v 5.6 hours in controls; P = .002). When all possible combinations of serum reactivity were considered, reactivity in the GA plus GIF assays had the best correlation with decreased recovery (R2 = .49; P less than .001) and t1/2 (R2 = .73; P less than .001). When the relationship between the strength of antibody reactivity and the recovery and t1/2 were analyzed, the best relationship was between the combination of LC and GIF with recovery (R2 = .62; P = .001). Because of the general availability of the HLA (LC) testing, the role of LC reactivity was investigated in other ways. There was a strong relationship between sera highly reactive by LC and those reactive by GIF. These highly reactive sera were also associated with reduced recovery and t1/2. The influence of specific HLA antigen mismatches was also studied. When donor and recipient were mismatched for the HLA-A2, B8, or BW44 antigens, there was a significant reduction in either recovery, t1/2, or both. Tissue localization was studied by body scans in patients with and without known sites of inflammation. Antibodies detected by a combination of GA and GIF caused abnormal pulmonary sequestration of granulocytes (three cases) and failure of granulocytes to localize at known sites of inflammation (three cases). HLA (LC) antibodies did not alter tissue localization despite the presence of the corresponding HLA antigens on granulocytes. It appears that GA, GIF, or a combination of these tests is the most effective predictor of altered in vivo fate of granulocytes. However, sera highly reactive by LC and GIF probably define a group of highly immunized patients in whom granulocyte recovery and t1/2 are also reduced. Mismatching for certain HLA antigens is also associated with reduced granulocyte recovery and survival. At present, GA, with or without the immunofluorescence assay, is the most effective predictor of altered in vivo granulocyte activity.(ABSTRACT TRUNCATED AT 400 WORDS)
A novel mutation in the TATA box in a Japanese patient with beta +- thalassemia
Authors: Takihara Y , Nakamura T , Yamada H , Takagi Y , Fukumaki Y 
Published: October 2019

Abstract
A single base substitution (A-G) at position -31 within the highly conserved proximal promoter element, the TATA box, was identified in the beta-globin gene cloned from a Japanese woman with beta +- thalassemia. It appears that she is homozygous for this specific allele, as determined by haplotype analysis using seven different polymorphic sites in the beta-globin gene cluster. Transient expression of the mutant gene in COS cells revealed a 45% reduction in beta-globin RNA production, relative to normal. These results establish the functional significance of the second base of the TATA box for in vivo transcription of the human beta-globin gene.
Thrombospondin in essential thrombocythemia
Authors: Lawler J , Cohen AM , Chao FC , Moriarty DJ 
Published: October 2019

Abstract
Essential thrombocythemia is a myeloproliferative disorder characterized by frequent bleeding and thrombotic complications. On a molecular level, two abnormalities of platelet thrombospondin have been identified: abnormal glycosylation of the intact 185,000-dalton chain has been detected and a shortened form of the thrombospondin chain is present. We have used two monoclonal antibodies and Lens culinaris lectin to probe the structure of thrombospondin in the platelets from three patients with essential thrombocythemia; one patient with polycythemia vera and two patients with secondary thrombocytosis. The presence of abnormal thrombospondin fragments with molecular weights of 160,000 and 30,000 was detected in the intact platelets and in the supernatant from thrombin-treated platelets, in all of the individuals except one of the secondary thrombocytosis patients. Monoclonal antibody binding studies indicate that both fragments are produced by proteolysis at a single site, which results in the removal of a 30,000- dalton fragment from the NH2-terminal. Lens culinaris lectin-binding studies revealed that some of the carbohydrate moieties of thrombospondin are near this cleavage site. The results are consistent with the hypothesis that the abnormal thrombospondin fragments observed under conditions of increased platelet production are due to increased susceptibility to proteolysis which, in turn, may be due to defective glycosylation.
Production of B cell growth factor(s) by neoplastic B cells from hairy cell leukemia patients
Authors: Ford RJ , Kwok D , Quesada J , Sahasrabuddhe CG 
Published: October 2019

Abstract
Recent studies have shown that normal human T cells contain a high- molecular-weight (mol wt) protein exhibiting B cell growth factor (BCGF) activity. Other studies have shown that virally transformed human B cells also secrete a high-mol-wt BCGF-like molecule in vitro. We have studied neoplastic B cells from patients with untreated hairy cell leukemia (HCL) to ascertain whether such cytoplasmic BCGF activity is present in the tumor cells. Studies on HCL cells from four patients indicated that BCGF-like activity was in fact present in the cytosolic extracts when tested on autochthonous HCL cells as well as on normal BCGF-dependent human B cell lines. Chromatographic analysis indicated that the BCGF activity from HCL cells was similar in mol wt as well as function to the normal T cell-derived cytosolic BCGF activity. These studies suggest that HCL cells contain and, in some cases, secrete a high-mol-wt growth factor that can be autostimulatory and appears to resemble a similar growth factor molecule found in normal human T cells.
Defective T cell responsiveness in chronic lymphocytic leukemia: analysis of activation events
Authors: Kay NE , Kaplan ME 
Published: October 2019

Abstract
Chronic lymphocytic leukemia (CLL) is a B cell disorder in which major T cell proliferative defects are present. We investigated the nature of this deficit by studying several parameters known to be crucial in normal T cell proliferative response to mitogen. Purified peripheral blood T cells from B-CLL patients were analyzed for the presence of T3 antigen. We observed that CLL T cells have a direct correlation between levels of T3 membrane antigen and proliferative response to mitogen. The appearance of activation antigens (transferrin, HLA-DR, and interleukin 2 [IL 2] receptor) was normal in CLL T cells post-mitogen exposure. Despite the normal presentation of IL 2 receptor on CLL T cell membrane, there was decreased production of IL 2 by CLL patients (v controls) (39.6 +/- 10.2 cells per milliliter v 64.6 +/- 11.0 cells per milliliter). Finally, we were able partially, but not fully, to reconstitute CLL T proliferative response to mitogen by adding purified exogenous IL 2. These findings suggest that CLL T cells have multiple defects that may impact on their proliferative potential. Further insight into these deficits may result in strategies that will facilitate immunologic restoration in T cells of these patients.
Iron metabolism in the Belgrade rat
Authors: Edwards J , Huebers H , Kunzler C , Finch C 
Published: October 2019

Abstract
Iron metabolism in the Belgrade rat was examined in the intact animal and in the reticulocyte suspensions. The plasma iron turnover was increased. However, when allowance was made for the effect of the elevated plasma iron concentration, erythroid marrow capacity for iron uptake was at basal levels. Numbers of erythroid cells in marrow and spleen measured by the radioiron dilution technique were increased. Thus iron uptake was not proportionate to the erythroid hyperplasia in the b/b rat, despite a more than adequate plasma iron supply. This relative deficiency in iron uptake was reflected in a severe microcytosis and elevated red cell protoporphyrin. Reticulocyte incubation studies demonstrated an unimpaired uptake of the transferrin- iron-receptor complex but a marked reduction in iron accumulation. The diferric transferrin molecule, when it did give up iron within the cell, released both of its iron atoms so that only apotransferrin was returned to the media. In contrast to the nearly complete release of iron within the normal reticulocyte, the major portion of iron taken up by the Belgrade reticulocyte was returned to the plasma. The release mechanism that can be impaired in iron-deficient reticulocytes by EDTA or cadmium was shown to be affected by lower concentrations of these substances in the Belgrade reticulocyte. It is concluded that the Belgrade rat has an abnormality of iron release within the absorptive vacuole that is responsible for a state of intracellular iron deficiency, involving the erythron and other body tissues.
The sensitivity to cytosine arabinoside of the blast progenitors of acute myeloblastic leukemia
Authors: Nara N , Curtis JE , Senn JS , Tritchler DL , McCulloch EA 
Published: October 2019

Abstract
Two culture methods are available for the study of the blast cells of acute myeloblastic leukemia (AML). One is an assay for clonogenic precursors; it depends on their ability to form blast colonies in culture in the presence of methylcellulose and suitable growth factors. The other assesses the growth of blast cells in suspension culture, where growth is measured by increasing numbers of clonogenic cells. We have compared the two methods as assays for the cytotoxic effects of the chemotherapeutic drug cytosine arabinoside (Ara-C). Marked patient- to-patient variation was found using either method; however, the slopes of the dose-response curves were usually greater when cells were exposed to drug in suspension rather than in methylcellulose. Control experiments showed that the difference could not be explained by drug carry-over from the suspension cultures to the methylcellulose plates when clonogenic cells in the suspensions were assessed. Further, the survival curves for Adriamycin were very similar, regardless of which assay was used. No correlation was found between D10 Ara-C values measured in suspension or in methylcellulose. However, a significant association with outcome was found between D10 Ara-C in suspension and response to treatment with a regimen in which Ara-C was the only chemotherapeutic agent used. No such association was detected when the D10 values obtained with the clonogenic assay were compared with outcome for the same group of 15 patients. Finally, a feasibility experiment was performed in which blast cells were exposed to Ara-C repeatedly during exponential growth over 238 days. A dose-related inhibition of growth was observed; no evidence was seen of emerging drug-resistant cells. Nor did the morphology of the cells change as a result of drug exposure. We conclude that drug sensitivities of AML blast cells in culture are dependent on measurement methods, even when techniques affecting cell proliferation are compared. Measurements of drug sensitivity in culture may best be interpreted when the bases of the assay systems are understood.
Diversity of human gamma-globin gene loci including a quadruplicated arrangement
Authors: Shimasaki S , Iuchi I 
Published: October 2019

Abstract
A quadruplicated gamma-globin gene as a (5′-G gamma-gamma-gamma-A gamma- 3′) was detected in an adult Chinese during a survey designed to detect G gamma- and A gamma-globin genes in Japanese. Five triplicated (-G gamma-gamma-A gamma-) and two single (-gamma-) haplotypes were also detected in 103 healthy adult Japanese. All of the unusual chromosomes appeared to reflect an unequal but homologous crossover between G gamma- and A gamma-globin genes. A new Bgl II polymorphic site located around the 3′ terminal region of the G gamma-globin gene was also discovered.
Abnormal in vitro differentiation of peripheral blood clonogenic B cells in common acute lymphoblastic leukemia during complete remission
Authors: Consolini R , Breard J , Bourinbaiar A , Goutner A , Georgoulias V , Canon C , Brugerie E , Mathe G 
Published: October 2019

Abstract
An in vitro B cell colony assay system was used to evaluate B cell growth from peripheral blood precursors in common acute lymphoblastic leukemia (CALL) patients in remission during maintenance therapy and in normal controls. Major differences between the two groups were found in the phenotypic and morphologic features of pooled colony cells. In both cases, the cells were E-. Controls' cells were surface immunoglobulin (sIg)-positive, and some (mean, 25%) expressed la determinants. By Wright-Giemsa staining, they appeared as plasmacytoid cells. In contrast, patients' cells had predominantly a lymphoblastoid appearance, fewer cells had developed sIg, and a large fraction (mean, 43%) were Ia-positive. Moreover, the CALL antigen (CALLA) was expressed by a mean of 18% (range, 2% to 72%) of the patients' colony cells, whereas CALLA was never found in control colonies. Thus, cells with immature features persist in the colonies of CALL patients. Secondary colonies could be generated from the patients' cultured cells, indicating their self-renewal capacity. CALLA + cells were also present in the secondary colonies. Finally, cytogenetic studies showed that a fraction of the patients' colony cells had karyotypic abnormalities similar to that of the original lymphoblasts. It is believed that in CALL patients this B cell assay permits the clonal expansion of residual circulating cells linked to malignant clones that are not detectable by classic hematologic and cytologic methods.
Pathways for the reduction of oxidized glutathione in the Plasmodium falciparum-infected erythrocyte: can parasite enzymes replace host red cell glucose-6-phosphate dehydrogenase?
Authors: Roth EF Jr , Schulman S , Vanderberg J , Olson J 
Published: October 2019

Abstract
Plasmodium falciparum-infected human red cells possess at least two pathways for the generation of reduced nicotinamide adenine dinucleotide phosphate (NADPH): (1) the glucose-6-phosphate dehydrogenase (G6PD) pathway and (2) the glutamate dehydrogenase (GD) pathway using glutamate as a substrate. Uninfected erythrocytes lack the GD pathway. The NADPH generated can be used to reduce oxidized glutathione (GSSG), which accumulates in the presence of an oxidative stress. In red cell G6PD deficiency, this pathway is reduced or absent, and the host cells as well as the parasites within them are vulnerable to oxidant stress. In view of the presence of the GD pathway in parasitized red cells and the recent description of a parasite-derived G6PD enzyme, we have asked whether the pathways for the reduction of GSSG provided by the parasite can substitute for the host G6PD in red cells deficient in G6PD activity. We have devised a functional assay in which the reduction rate of GSSG is monitored in the presence of buffered infected or control red cell lysates and substrates. Infected G6PD-deficient erythrocytes were obtained from in vitro cultures after a single prior growth cycle of the parasites in G6PD deficient cells to eliminate contaminating normal red cells. The results show that only parasitized red cells can reduce GSSG via the GD pathway. In parasitized G6PD Mediterranean red cells (completely G6PD-deficient), there is a detectable GSSG reduction via the G6PD pathway, not found in uninfected lysates from the same individual. In G6PD A- (African type, featuring partial deficiency), a small increment in the G6PD-dependent reduction of GSSG can also be detected. However, when compared to G6PD normal red cells, the activities from the parasite-derived pathways are small and could not be considered substitutes for normal host enzyme activity. It is concluded that while the plasmodium provides additional pathways for the generation of NADPH that may serve its own metabolic needs, the host red cells and hence the parasite itself remain vulnerable to oxidant stress.
Platelet storage pool deficiency in pigs
Authors: Daniels TM , Fass DN , White JG , Bowie EJ 
Published: October 2019

Abstract
We report a new bleeding disease--storage pool deficiency (SPD) of platelets--in pigs from the Mayo swine colony of homozygous von Willebrand's disease (vWD) and of heterozygous carriers of vWD. Levels of factor VIII, von Willebrand factor antigen (vWF:Ag), and ristocetin cofactor (RCof) were similar in the vWD carriers and SPD pigs. The latter pigs, however, had bleeding times of 15 minutes or more and were severe bleeders, in contrast to clinically normal vWD carriers. Platelet aggregation in response to collagen was reduced in most SPD pigs. Total platelet content of ADP, ATP, and serotonin was less than that of normal pigs. While the initial uptake of 14C-labeled serotonin into platelets was similar in SPD and normal pigs, retention of serotonin was reduced in platelets of SPD pigs. Transmission electron microscopy showed a large decrease of dense bodies in the platelets of SPD pigs. These findings support a diagnosis of SPD. Genetic analyses suggest an autosomal recessive mode of inheritance. A breeding program is under way to produce pigs affected only at the SPD gene, thus allowing further characterization of SPD and SPD-carrier pigs.
Red cell rheology in stomatocyte-echinocyte transformation: roles of cell geometry and cell shape
Authors: Reinhart WH , Chien S 
Published: October 2019

Abstract
The influence of the shape of the red blood cell during stomatocyte- echinocyte transformation on its deformability was studied by microsieving through pores with diameters of 2.6, 4.5, and 6.9 micron. A stomatocytic transformation was produced by chlorpromazine (0.02, 0.1, and 0.5 mmol/L) and an echinocytic transformation by sodium salicylate (7.5, 30, and 120 mmol/L). For spherostomatocytes, an increase in filtration resistance through 2.6 and 4.5 micron pores was observed, whereas for spheroechinocytes, a decrease in filtration resistance through 2.6 micron pores was found. Larger pores (6.9 micron) were not sensitive to those shape changes. The changes in deformability can be explained by the fact that the surface area of (sphero)-stomatocytes decreased, whereas that of (sphero)-echinocytes increased; the cell volume remained essentially constant. Echinocytes produced by 24-hour adenosine triphosphate depletion differed from drug- induced echinocytes: they had an increased cell volume at constant surface area and consequently an increased filtration resistance through 2.6- and 4.5-micron filter pores. Shape changes with spicule formation are therefore not a homogeneous entity, and cell geometric factors (eg, surface area and volume) must be assessed with care. The viscosity of red cell suspensions at a hematocrit level of 45% was higher for drug-induced echinocytes than discocytes or stomatocytes at all shear rates tested. We conclude that the normal discocyte represents an optimum shape for the flow in vivo since a stomatocytic transformation could impair the passage through the microcirculation (decrease in cell filterability) and an echinocytic transformation could impair the flow in larger vessels (increase in blood viscosity).