bluuebunny/crossref_metadata_2025_split huggingface dataset:
The resistance of fibrinogen and soluble fibrin monomer in blood to degradation by a potent plasminogen activator derived from cadaver limbs
Authors: Gurewich V , Hyde E , Lipinski B 
Published: October 2019

Abstract
The effect of a cadaver-derived vascular plasminogen activator (VA) on the degradation of fibrinogen, soluble fibrin monomer, and fibrin was studied and compared with the effect of equivalent fibrinolytic potencies of streptokinase (SK), urokinase (UK), and plasmin. The proteolytic activity of the three activators and plasmin was determined by a standard fibrin plate assay and was expressed in CTA units from a UK reference curve. Fibrinogen degradation was measured by clottable protein determinations and by an electrophoretic technique sensitive to small changes in the molecular weight of fibrinogen. When VA was incubated in plasma, no degradation of fibrinogen occurred, whereas rapid fibrinolysis took place after the plasma was clotted. By contrast, equivalent potencies of SK, UK, and plasmin caused extensive fibrinogenolysis. Since the plasmin added and that formed by the three activators had equivalent fibrinolytic activity, the failure of VA to induce fibrinogen degradation was attributed to antiactivators rather than antiplasmins. VA activity in plasma was consumed by clotting, whereas the antiactivator activity remained in the serum, suggesting dissociation of the VA-antiactivator complex on the fibrin clot. Fibrinogen and its soluble derivatives resisted degradation by VA in plasma because a solid phase appeared necessary for the complex to dissociate. The findings indicated that the degradation of fibrinogen or soluble fibrin in blood as a result of plasminogen activation by VA was unlikely to occur due to a large excess of antiactivator activity. Alternative pathways for their catabolism are discussed.
Iron metabolism, sickle cell disease, and response to cyanate
Authors: Peterson CM , Graziano JH , de Ciutiis A , Grady RW , Cerami A , Worwood M , Jacobs A 
Published: October 2019

Abstract
In an attempt to understand the variability of the hematologic response to oral sodium cyanate, iron metabolism was studied in a group of 39 patients with sickel cell disease. Eleven of the 39 patients were found to have no stainable iron in the marrow despite the fact that patients with sickle cell disease are generally considered to have hemosiderosis. The mean per cent saturation and total iron-binding capacity were in the low-normal range in sickle cell patients whether or not stainable iron was present in the bone marrow aspirate. Serum ferritin concentrations, on the other hand, were found to be high in both groups (greater than 500 mu g/liter) when compared to controls (60 mu g/liter). The high serum ferritin levels denoted significant total- body iron deposition which may be unavailable for normal metabolic processes. One patient with no stainable iron in the bone marrow aspirate did respond to iron therapy alone with an increase in hemoglobin concentration. Serum ceruloplasmin levels were also found to be high in sickle cell disease patients. The ability to respond to oral cyanate therapy was correlated with the amount of stainable iron in the bone marrow aspirate. These studies emphasize the necessity of a reevaluation of iron metabolism in the pathophysiology and treatment of sickle cell disease.
Glucose 6-phosphate dehydrogenase deficiency and sickle cell anemia: frequency and features of the association in an African community
Authors: Bienzle U , Sodeinde O , Effiong CE , Luzzatto L 
Published: October 2019

Abstract
The glucose 6-phosphate dehydrogenase (G6PD) genotype was determined in 100 male patients with homozygous sickle cell anemia (SS) by a combination of quantitative assay, cytochemical testing, and starch-gel electrophoresis. Of the 100 patients tested, 16 were found to be G6PD deficient (GdA-), AND 84 G6PD normal (22GsA and 62 GdB). This distribution of G6PD genotypes did not differ significantly from that observed in the general population. The level of G6PD activity in GdA- SS patients was nearly always higher than in G6PD-deficient subjects who did not have an associated hemolytic state, but it was nearly always lower than in G6PD-normal subjects. The clinical course of sickle cell disease, including the degree of anemia, was not milder in GdA- than in G6PD-normal patients but could not be proved to be significantly more severe. It was concluded that in this community the incidence of G6PD deficiency in sickle cell anemia was not greater than would be expected by chance, and there was no evidence that the coexistence of the GdA- gene in SS patients ameliorated their disease.
Limitation of splenic growth as studied by heterotopic splenic implants
Authors: Tavassoli M 
Published: October 2019

Abstract
Multiple spleens were implanted in the subcutaneous tissue or the peritoneal cavity of inbred rats which had undergone splenectomy. The total weight of regenerated implants was compared to the weight of implanted tissue. The weight of recovered tissue was not a function of implanted spleen mass; rather, it approximated the unit ratio of the animal's own spleen. Those animals receiving more than ten spleens died by days 3–6 postimplantation, probably as a result of massive necrosis that occurred during the process of regeneration. When implants were made in a temporal sequence of two spleens every 3 days, the first set was uniformly successful, whereas regeneration was aborted in subsequent sets of implants. These observations are consistent with the conclusion that certain factors control the total mass of spleen in any one animal.
Osmotic behavior of normal and leukemic lymphocytes
Authors: Ben-Sasson S , Shaviv R , Bentwich Z , Slavin S , Doljanski F 
Published: October 2019

Abstract
The response of normal human peripheral blood lymphocytes to a hypotonic environment may be divided into two phases: the cells first exhibit rapid osmotic swelling, followed by a slower shrinking phase, during which they regain their initial physiologic volume. This osmotic behavior is characteristic of most mammalian and avian nucleated cells so far examined. The normal human blood lymphocyte, however, shows the most rapid recovery phase (5 min). Lymphocytes from chronic lymphatic leukemia patients, in comparison, show a strikingly slower rate of return to their initial isotonic volumes. The mechanism underlying osmotic cell volume regulation and its significance are discussed.
Granule enzymes of polymorphonuclear neutrophils: A phylogenetic comparison
Authors: Rausch PG , Moore TG 
Published: October 2019

Abstract
The functional significance of granule enzymes in polymorphonuclear leukocytes (PMN) is not fully understood because of the multiplicity of the enzymes and the rare occurrence of deficiencies in man. In order to select appropriate laboratory animals for functional studies, a phylogenetic comparison of enzyme levels in animal and human PMN was undertaken. Neutrophils were obtained from a variety of laboratory animals and man; the activities of alkaline phosphatase, lysozyme, myeloperoxidase, and beta-glucuronidase were determined by histochemical and analytical techniques. Marked interspecies differences in enzyme activity were found; many species were deficient in alkaline phosphatase or lysozyme. Differences in pH optima and metal requirements of alkaline phosphatase were not of sufficient magnitude to explain the variations of this enzyme.
Growth stimulation of human bone marrow cells in agar culture by vascular cells
Authors: Knudtzon S , Mortensen BT 
Published: October 2019

Abstract
Human vascular cells are capable of stimulating granulopoiesis in agar culture of human bone marrow cells. This effect was obtained by including vein fragments in the culture or by using endothelial cells separated from the vein of human umbilical cords as feeder cells. Furthermore, the stimulatory capacity of conditioned medium obtained from cord veins was found to be highly active in comparison to that obtained from peripheral leukocytes. Endothelial cells within the bond marrow cavity are suggested as a local source of factors regulating granulopoiesis in humans in addition to the monocyte.
Micropinocytosis of transferrin by developing red cells: an electron- microscopic study utilizing ferritin-conjugated transferrin and ferritin-conjugated antibodies to transferrin
Authors: Sullivan AL , Grasso JA , Weintraub LR 
Published: October 2019

Abstract
Electron-microscopic examination of rat reticulocytes and normoblasts incubated with transferrin conjugated to ferritin or ferritin-labeled antitransferrin revealed binding of ferritin conjugates to the surface membrane, and uptake of ferritin conjugates in micropinocytotic vesicles. No binding or endocytosis of ferritin was visualized when rat reticulocytes or normoblasts were incubated with ferritin alone or ferritin conjugated to nonspecific rabbit IgG. These observations support the concept that transferrin binds to a surface membrane receptor and is subsequently internalized by the developing red cell. Time course and temperature dependence studies suggest the endocytosis of transferrin may be an important mechanism in delivery of iron to the developing red cell.
The binding of human and bovine thrombin to human platelets
Authors: Shuman MA , Tollefsen DM , Majerus PW 
Published: October 2019

Abstract
Human thrombin binds to specific receptors on the surface of human platelets in a manner analogous to bovine thrombin. Thus, two classes of binding are observed--high affinity with a dissociation constant (Kdiss) of 0.02 U/ml and low affinity with a Kdiss of 5 U/ml. Bovine and human thrombin bind to the same platelet receptors, although bovine thrombin binds with slightly greater affinity. When the amount of thrombin bound to platelets is related to the extent of 14C-serotonin release, bovine and human thrombin are equally effective. Antibodies to human and bovine thrombin were found to differ markedly in their ability to precipitate thrombin of the two species. Thus, antibovine thrombin precipitated eightfold more bovine thrombin than human thrombin, while antihuman thrombin precipitated tenfold more human thrombin than bovine thrombin. Similar differences were found in the ability of Fab fragments of these antibodies to block the interaction of thrombin of each species with human platelets. The finding that both species of thrombin, despite significant evolutionary differences in primary structure, retain essentially identical binding sites to platelets suggests that this part of the thrombin molecule is physiologically important and supports our hypothesis of a role for thrombin binding to platelets in platelet function and hemostasis.
A new method for studying splenic reticuloendothelial dysfunction in sickle cell disease patients and its clinical application: a brief report
Authors: Casper JT , Koethe S , Rodey GE , Thatcher LG 
Published: October 2019

Abstract
Differential interference contrast (DIC) microscopy (Nomarsky optics) readily demonstrates the formation of “pits” or crater-like depressions in red cell membranes of splenectomized individuals. Splenic reticuloendothelial dysfunction characteristic of many patients with sickle cell disease (SCD) can be demonstrated by technetium spleen scans, but this technique is expensive, requires injection of radioactive material into children, and is cumbersome to perform at regular intervals. However, pit formation in red cells, which also appears to reflect splenic dysfunction, can readily be quantitated in a finger-stick blood sample using DIC microscopy. In this study, the degree of red cell pitting was compared with results of technetium spleen scans and measurements of Howell-Jolly bodies in individuals with sickle cell disease. The average pitted cell percentage in the control population was 0.5% +/- 0.5 (range 0.0–2.6) and 30.5% +/- 13.9 in the SCD population (range 2.4-71.1) (less than 0.001). Of the individuals studied with SCD, 12 also had technetium (99mTc) sulfur colloid scans and measurements of Howell-Jolly bodies. The percentage of Howell-Jolly bodies was low and did not correlate well with the degree of splenic visualization. However, there was an excellent correlation between pit count and splenic dysfunction as measured by spleen scan. Determination of red cell pitting, therefore, appears to offer a simple means for clinical evaluation of splenic reticuloendothelial function in patients with SCD.
Preleukemia and leukemia in polycythemia vera
Authors: Meytes D , Katz D , Ramot B 
Published: October 2019

Abstract
A group of 76 polycythemia vera patients was followed prospectively with bone marrow examinations at regular intervals. Six terminated in acute leukemia, preceded by an indolent preleukemic phase succeeded by a very fulminant leukemia. At autopsy, all patients had extramedullary hematopoiesis. In one of them, only the bone marrow was leukemic, suggesting that it was the primary site of this transformation. In three with leukemic involvement of nonhematopoietic organs, the infiltrate consisted of myelo- or myelomonoblasts and normoblasts. The preleukemic phase was characterized by a rapidly evolving spontaneous pancytopenia, with a drop from polycythemic blood counts within 2 mo. In the bone marrow, megaloblastoid erythropoiesis with ring sideroblasts was prominent. A similar preleukemic phase evolving in other potentially leukemic conditions, has been described. Therefore, in patients at risk, the appearance of ring sideroblasts may be regarded as an early indicator of imminent acute leukemic transformation.
Platelet release abnormality associated with a variant of von Willebrand's disease
Authors: Dowling SV , Muntz RH , D'Souza S , Ekert H 
Published: October 2019

Abstract
A family with a platelet release abnormality (PRA) is described. The only son also showed a reduced rate of platelet aggregation in response to ristocetin, markedly reduced levels of von Willebrand's factor (vWf, ristocetin cofactor), and increased mobility of factor VIII-like antigen, features which were suggestive of von Willebrand's disease (vWd). No inhibition of vWf was found in his plasma. Family studies showed no evidence of vWd in the mother. The father's investigations showed a low rate of ristocetin aggregation on one of the two occasions when it was tested and low vWf on two of four occasions. Despite repeated testing, the findings in the father did not conclusively rule out the possibility of mild vWd, and it was impossible to determine whether the vWd in the son was inherited or arose as a mutation. The findings in this family suggest a possible relationship between abnormalities of the factor VIII complex and defective platelet function.
Human bone marrow lymphocytes: B and T cell precursors and subpopulations
Authors: Abdou NL , Alavi JB , Abdou NI 
Published: October 2019

Abstract
Characterization of the different lymphocyte populations in normal human bone marrow (BM) was attempted and compared to that in the peripheral blood (PB). B cells comprised 34% +/- 11% of lymphocytes in BM and 23% +/- 9% in PB. The majority of B cells carried IgM in BM and IgG in the PB. In the BM, cells carrying complement or Fc receptors were fewer than cells carrying Ig, but in the PB they were equal. T cells comprised 6% +/- 4% of lymphocytes in the BM and 62% +/- 7% in the PB. The majority of BM lymphocytes did not have B or T cell markers; these probably included B and T cell precursors. BM lymphocytes carrying surface Ig increased in a 7-day culture, whereas those of the PB decreased. Pokeweed mitogen induced Ig synthesis in B cells of PB but not those of BM. BM-T cells were more efficient than PB- T cells in inhibiting Ig synthesis of PB-B cells. These results indicate that the BM compartment contains immature B cells that are capable of partial differentiation and maturation in vitro. BM-B lymphocytes are probably not involved in the effector phase of the immune response since they are unable to synthesize Ig and because they carry few receptors for complement of Fc, BM-T lymphocytes are very few and have suppressor capability and therefore may play an essential role in regulation of Ig synthesis by B cells.
Lipid membrane peroxidation in beta-thalassemia major
Authors: Rachmilewitz EA , Shohet SB , Lubin BH 
Published: October 2019

Abstract
The composition of membrane lipids was studied in 17 splenectomized and eight unsplenectomized patients with beta-thalassemia major and compared to normal controls. The results showed a nearly twofold increase in total cell lipids; a reduction in the percentage, but not the absolute amount of phosphatidylethanolamine, and a corresponding increase in phosphatidylcholine in the lipids; a considerable increase in the percentage of the saturated fatty acid, palmitic acid, and a reciprocal decrease in the polyunsaturated fatty acid, arachidonic acid; a twofold increase in the amount of malonyldialdehyde (MDA) generated after peroxide threat to the RBC when calculated either per gram hemoglobin or per cell; no change in the amount of MDA generated when calculated per microgram of membrane phosphorus at risk per cell; and a considerable decrease in serum alpha-tocopherol (vitamin E) levels. Thalassemic erythrocytes contain more lipid per cell which is susceptible to peroxidation. In addition, the distribution of fatty acids in these cells suggests that autooxidation of that lipid may have occurred. Autooxidation may be initiated by free radicals, which are constantly formed in the normal red cell, and may be especially prevalent when unstable hemoglobins are present. The low MCHC or some other intracellular defect of thalassemic cells may allow such potent oxidants to find their way to the cell membrane. Vitamin E, a biologic antioxidant is decreased in these patients, and clinical supplementation may be indicated to prevent some of the membrane damage in thalassemia.
Activation of the coagulation system in polycythemia vera
Authors: Carvalho A , Ellman L 
Published: October 2019

Abstract
Thrombosis is one of the major complications of polycythemia vera. Seventeen patients with polycythemia vera in good hematologic control were evaluated for abnormalities of the coagulation system. Activation of the intrinsic coagulation cascade was suggested by low levels of factor XII, prekallikrein, and kallikrein inhibitors in 12 of 17 patients. The group also demonstrated a significant increase in soluble fibrin complexes using plasma gel filtration on 4% agarose. Fibrin degradation products were normal and antithrombin III levels were slightly elevated. It appears that patients with polycythemia vera have chronic activation of the coagulation system, probably initiated by activation of factor XII. No correlation between the degree of coagulation abnormalities and thromboembolic complications was evident in this group of patients.
Hemoglobin pyrgos alpha2 beta2 83 (EF7) Gly leads to Asp: a new hemoglobin variant in double heterozygosity with hemoglobin S
Authors: Tatsis B , Sofroniadou K , Stergiopoulos CI 
Published: October 2019

Abstract
An electrophoretically fast-moving hemoglobin variant was found to be present together with hemoglobin S, in the hemolysate of the rythrocytes of at 3-yr-old Greek boy. Electrophoresis of the parents' erythrocyte hemolysates revealed that the father was an AS heterozygote, while the mother was a carrier of the variant hemoglobin. A sibling was also found to be a carrier. The amount of the mutant hemoglobin in the peripheral blood of the propositus, his mother, and his brother was 62.2%, 52.5%, and 51.1%, respectively, as determined by column chromatography. The patients peripheral blood smear showed mild anisocytosis, microcytosis, and hypochromia. Similar but less pronounced red cell abnormalities were found in the other two carriers. Structural analysis of the variant hemoglobin revealed substitution of an aspartic acid for the glycine residue at the beta83 (EF7) position. This new hemoglobin was named hemoglobin Pyrgos. All the carriers of hemoglobin Pyrgos are clinically healthy, and there seems to be no interaction between hemoglobin Pyrgos and hemoglobin S as manifested clinically.
Colony-stimulating factor in patients with chronic neutropenia
Authors: Wewerka JR , Dale DC 
Published: October 2019

Abstract
Urinary and serum colony-stimulating factor (CSF) levels were measured in 11 patients with chronic idiopathic neutropenia without infections and in 10 normal individuals. Urinary CSF output was determined using mouse marrow target cells, and serum CSF activity was assayed with human marrow target cells by the double agar layer technique. Using these methods, there was no significant difference between CSF levels of neutropenic and normal subjects. These data indicate that CSF levels are not inversely related to the blood neutrophil count in chronic idiopathic neutropenia and suggest that CSF is not a hormone regulating the blood neutrophil count in a manner analogous to the erythropoietin regulation of circulating erythrocyte levels.
Experimental Pseudomonas pneumonia in leukopenic dogs: comparison of therapy with antibiotics and granulocyte transfusions
Authors: Dale DC , Reynolds HY , Pennington JE , Elin RJ , Herzig GP 
Published: October 2019

Abstract
Pseudomonas aeruginosa pneumonia was produced in dogs with radiation- induced leukopenia to study the comparative efficacy of several different therapies. In a randomized control trial, five treatment regimens were compared: no antibiotics or granulocytes (controls), gentamicin (5 mg/kg/day), carbenicillin (500 mg/kg/day), gentamicin and carbenicillin (same dosages), and daily granulocyte transfusion (minimum 5 x 10(9) cells/day) plus gentamicin (5 mg/kg/day). The most effective therapy was gentamicin plus granulocyte transfusions. Gentamicin alone was not significantly better than no specific therapy. Carbenicillin with or without gentamicin gave intermediate results. This study further supports the utility of granulocyte replacement therapy of infections in severely granulocytopenic subjects. The results also indicate that the relative value of granulocyte transfusions depends upon the specific antibiotic regimen with which these transfusions are compared.
Assessment of erythrocytic and granulocytic colony formation in an in vivo plasma clot diffusion chamber culture system
Authors: Steinberg HN , Handler ES , Handler EE 
Published: October 2019

Abstract
Normal rat bone marrow cells seeded into a plasma clot diffusion chamber culture developed into erythrocytic and granulocytic colonies in vivo. Chambers implanted into the peritoneal cavity of normal hosts showed erythrocytic colony numbers reaching an initial peak on day 2, declining on days 3--5, and increasing in a secondary growth phase on day 7. Day 2 colonies were evenly dispersed; day 7 colonies were grouped into discrete areas of bursts. Granulocytic colony numbers reached a peak on day 4 and gradually declined through day 7. Cells in various stages of differentiation could be detected in both colony types. Colony numbers were proportional to the number of marrow cells seeded into the chamber. Host animals treated with phenylhydrazine induced a marked increase in erythrocytic colony numbers and size and a decrease in granulocytic colony formation. Host animals treated with endotoxin suppressed erythrocytic colonies while increasing granulocytic colony size. This method may prove advantageous for the study of hematopoietic colony formation in a physiologic environment.