bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cobalamin (vitamin B12) deficiency detection by urinary methylmalonic acid quantitation
Authors: Norman EJ , Martelo OJ , Denton MD 
Published: October 2019

Abstract
A study was made to assess the value of cobalamin deficiency detection through quantitation of urinary methylmalonic acid (MMA). Urinary MMA was measured in 1118 patients suffering from megaloblastic anemia, other anemias, elevated red cell mean corpuscular volume, or unexplained neurologic disorders. Patients without proven cobalamin deficiency had urinary MMA levels less than 20 micrograms/ml. All patients (n = 27) confirmed to have cobalamin deficiency showed MMA levels greater than 20 micrograms/ml. Data are presented showing the Schilling test results, the comparison of serum cobalamin to urinary MMA levels, and other basic hematologic data. MMA levels are a good indication of cobalamin distribution and function since they are directly related to a cobalamin-dependent metabolic pathway. With rapid, reliable quantitation by mass spectrometry, urinary MMA can now be a useful clinical test.
A new acute leukemia-associated blast cell antigen detected by a monoclonal antibody
Authors: Billing R , Lucero K , Shi BJ , Terasaki PI 
Published: October 2019

Abstract
A monoclonal mouse antibody has been raised to the common acute lymphoblastic leukemia (cALL) cell line Reh. It is a cytotoxic antibody of the IgG2, subclass that reacts with leukemia cells from the following patients: 69% non-B non-T ALL, 50% T-ALL, 18% acute myeloblastic leukemia (AML), and 66% chronic myeloid leukemia (CML) blast crisis lymphoid cells. Other types of leukemia and all normal blood cells tested were negative, including T and B lymphocytes, granulocytes, monocytes, erythrocytes, and spleen cells. The detected antigen appears to be a type of blast cell antigen because it is also present on phytohemagglutinin (PHA) blast cells, myeloblast from normal bone marrow cells (by CFU-C), and all lymphoblastoid cell lines tested. Only one active antibody species could be detected by preparative isoelectric focusing on polyacrylamide gels and by protein-A-Sepharose affinity chromatography.
Characterization of human erythroid burst-promoting activity derived from bone marrow conditioned media
Authors: Porter PN , Ogawa M 
Published: October 2019

Abstract
Bone marrow conditioned media (BMCM) increases burst number and the incorporation of 59Fe into heme by bursts when peripheral blood or bone marrow cells are cultured at limiting serum concentrations. Burst- promoting activity (BPA) has now been purified approximately 300-fold from this source by ion-exchange chromatography on DEAE-Sephadex and absorption chromatography on hydroxyapatite agarose gel. Marrow BPA increased burst number and hemoglobin (Hb) synthesis in a dose- dependent manner. A larger increase in Hb synthesis than in burst number was consistently observed, which was probably a consequence of the increase in the number of cells per burst that occurs in the presence of BPA. The role of BPA in culture could be distinguished from erythropoietin (Ep), since no bursts grew in the absence of Ep, whether or not BPA was present, and since it had no effect on the growth of erythroid colonies scored at day 5 of culture. Our purified fraction did not support the growth of CFU-C in culture. Activity was stable at temperatures of 70 degrees C or lower for 10 min; exposure to 80 degrees C resulted in approximately 50% loss of activity. BPA was completely inactivated by treatment at 100 degrees C for 10 min. Thus, human bone marrow cells produce a heat-sensitive factor that specifically promotes the growth of early erythroid progenitors in culture.
The contact activation mechanism in human plasma: activation induced by dextran sulfate
Authors: van der Graaf F , Keus FJ , Vlooswijk RA , Bouma BN 
Published: October 2019

Abstract
Incubation of normal human plasma with dextran sulfate for 7 min at 4 degrees C generates kallikrein amidolytic activity. No kallikrein activity is generated in factor XII or prekallikrein-deficient plasma and only small amounts (8%) in high molecular weight (HMW) kininogen- deficient plasma. Addition of specific antisera directed against prekallikrein or HMW kininogen to normal plasma blocked the generation of kallikrein activity by dextran sulfate. Thus, factor XII, prekallikrein, and HMW kininogen are essential components for optimal activation of prekallikrein. The role of limited proteolysis in the activation of prekallikrein induced by dextran sulfate was studied by adding 125I-prekallikrein to plasma. The generation of kallikrein activity paralleled the proteolytic cleavage of prekallikrein as judged on SDS gels in the presence of reducing agents. The same cleavage fragments were observed as obtained by activation of purified prekallikrein by beta-factor-XIIa. Addition of 131I-HMW kininogen and 125I-factor XII or 131I-HMW kininogen and 125I-prekallikrein to normal plasma followed by activation with dextran sulfate and analysis on SDS gels indicated that the observed cleavage of prekallikrein and HMW kininogen is fast compared to the observed cleavage of factor XII, which is much slower and less extensive. During the first minutes of incubation of normal plasma with dextran sulfate, mainly alpha-factor- XIIa is formed. During prolonged incubation, beta-factor-XIIa is also formed.
Multimeric composition of factor VIII/von Willebrand factor following administration of DDAVP: implications for pathophysiology and therapy of von Willebrand's disease subtypes
Authors: Ruggeri ZM , Mannucci PM , Lombardi R , Federici AB , Zimmerman TS 
Published: October 2019

Abstract
We have studied the modifications in the multimeric composition of plasma factor VIII/von Willebrand factor and the bleeding time response following administration of 1-Deamino-[8-D-arginine]-Vasopressin (DDAVP) to patients with different subtypes of von Willebrand's disease. In type I, all multimers were present in plasma in the resting state, though they were decreased in concentration. Administration of DDAVP resulted in an increased concentration of these forms as well as the appearance of larger forms than were previously present. There was concomitant correction of the bleeding time. In type IIA, large multimers were absent in the resting state, and although DDAVP induced an average threefold increase in the plasma concentration of factor VIII/von Willebrand factor, the larger multimers did not appear and the bleeding time, although shortened, was not corrected. In contrast, the larger multimers that were also absent from type IIB plasma in the resting state rapidly appeared following DDAVP administration. However, their appearance was transitory and the bleeding time, as in IIA patients, was shortened but not corrected. The characteristic multimeric composition of platelet factor VIII/von Willebrand factor in given subtypes predicted the alteration in plasma factor VIII/von Willebrand factor induced by DDAVP. These studies provide evidence that the different subtypes of von Willebrand's disease represent distinct abnormalities of factor VIII/von Willebrand factor. They also suggest that complete hemostatic correction following DDAVP can be routinely expected only in type I von Willebrand's disease, and only if factor VIII/von Willebrand factor can be raised to normal levels.
Human neutrophil-specific granule deficiency: a model to assess the role of neutrophil-specific granules in the evolution of the inflammatory response
Authors: Gallin JI , Fletcher MP , Seligmann BE , Hoffstein S , Cehrs K , Mounessa N 
Published: October 2019

Abstract
It has been suggested that neutrophil (PMN) specific granules are important in cell aggregation, locomotion, hydroxyl radical formation, and in extracellular functions such as the generation of complement- related inflammatory mediators (C5a) and the feedback regulation of myelopoiesis. In the current studies, a 9-yr-old boy with a history of recurrent infections and specific granule deficiency (absent lactoferrin, B-12 binding proteins, and characteristic specific granules on sucrose gradient centrifugation of cell homogenates) was studied to assess some of these concepts. In vivo, the patient had decreased PMN and monocyte accumulation into Rebuck skin windows but an expected febrile episode with an associated neutropenia (PMN margination) and neutrophilia (mobilization of marrow reserves) in response to intravenous endotoxin. In vitro, the patient's resting PMN showed increased ruffling, increased surface-to-volume ratio, and increased numbers of centriole-associated microtubules. His PMN showed a significant decrease in cell negative surface charge (which may relate to aggregation) in response to several stimuli and adhered better than normally to plastic. In addition, his PMN aggregated normally in response to the chemoattractant f-met-leu-phe, although the subsequent disaggregation normally seen with PMN did not occur with the patients cells. Chemotaxis of the patient's PMN to several stimuli was abnormal, and specific saturable and displaceable binding of the chemoattractant f-met-leu-[3H]phe was decreased. Similarly, following incubation with secretagogues, there was a less than normal increase in f-met-leu-[3H]phe binding and an absence of the normal increases in PMN surface area. The patient's PMN bactericidal activity, stimulated oxygen metabolism (cytochrome-c reduction, chemiluminescence, and NBT reduction), and elicited changes in membrane potential were also abnormal. Studies assessing the mechanism for the abnormal monocyte accumulation into skin windows indicated the patient's monocyte chemotaxis was better than normal in vitro. However, the patient's PMN homogenates lacked a stimulus of monocyte locomotion and did not generate chemotactic activity normally from serum. Thus, the data indicate that specific granule constituents are not required for neutrophil margination in vivo or aggregation in vitro. However, the data support the concept that PMN-specific granules are important for PMN locomotion and oxidative metabolism. In addition, extracellular release of specific granule constituents appears to be important for amplification of the initial and subsequent phases of the inflammatory response.
Phagocytosis-induced chemotaxis receptor cycling in neutrophils is mediated by thiol oxidation
Authors: Lane TA , Lamkin GE 
Published: October 2019

Abstract
We previously demonstrated that neutrophil (PMN) phagocytosis of opsonized zymosan (OPZ) caused oxygen-dependent inhibition of chemotactic peptide receptor (CPR) binding using the ligand 3H-formyl- methionyl-leucyl-phenylalanine (3H-FMLP). In the current studies we sought to determine the mechanism of CPR inhibition by OPZ. We found that 3 mM cysteine and 5 mM dithiothreitol (DTT) did not decrease PMN phagocytosis, but abolished CPR inhibition by OPZ. Furthermore, incubation of PMN with DTT after OPZ partially restored the suppressed CPR. PMN CPR saturation studies with 3H-FMLP on PMN incubated with or without DTT after phagocytosis indicated that DTT restored receptor numbers to 92% +/- 6% of prephagocytosis values and also improved CPR affinity for 3H-FMLP. In additional studies we found that the cell penetrating thiol reagents mercuric chloride (HgCl2), N-ethylmaleimide (NEM), and diamide, but not the nonpenetrating agents p- chloromercuriphenylsulfonic acid and p-chloromercuribenzoate, caused rapid, dose-dependent, DTT-inhibitable suppression of up to 85% CPR binding. CPR inhibition by HgCl2 and NEM was irreversible. PMN CPR saturation studies showed that NEM decreased total receptor numbers, not CPR affinity. The effect of NEM was not inhibited by receptor occupancy at 4 degree C or at 37 degree C. These studies indicate that: (1) intact thiol groups are a requirement for CPR ligand-binding; (2) the thiol groups are presumptively located on the interior side of, or within hydrophobic portions of, the plasma membrane and are not part of the 3H-FMLP binding site; (3) thiol oxidation-reduction induces reversible alteration in CPR binding; (4) phagocytosis-induced modulation of the CPR is due, in part, to thiol oxidation. These studies suggest that postphagocytic, thiol-mediated reduction in CPR binding may play a physiologic role in the inhibition of PMN chemotaxis at inflammatory sites. The state of CPR-associated thiols may be an important determinant of CPR binding under physiologic conditions other than phagocytosis.
Nucleic Acids of Rabbit Reticulocytes
Authors: BURT N. S. , MURRAY R. G. E. , ROSSITER R. J. 
Published: October 2019

Abstract
1. The concentration of acid soluble phosphorus, lipid phosphorus and nucleic acid phosphorus was determined in the red cells and polymorphonuclear leukocytes of the rabbit. The concentration of acid soluble phosphorus was of the same order in both types of cells, but there was more lipid phosphorus and nucleic acid phosphorus in the polymorphonuclear leukocytes than in the red cell. Over 80 per cent of the nucleic acid in white cells was of the desoxypentose type.
2. Immature cells were produced in the peripheral blood stream of rabbits either by the administration of phenylhydrazine or by successive bleedings. Either treatment caused a fall in the concentration of hemoglobin, the red cell count and the hematocrit with an increase in the mean corpuscular hemoglobin. There was also an increase in the concentration of acid soluble phosphorus and lipid phosphorus and a great increase in the concentration of nucleic acid phosphorus which was coincident with the increase in number of immature cells as judged by the reticulocyte count. Almost all of the excess nucleic acid was of the pentose type.
3. The basophilia of the immature cells disappeared after treatment with ribonuclease or after hydrolysis with normal hydrochloric acid. Desoxyribonuclease was without effect.
4. These results suggest that the basophilic substance of the immature rabbit red cell, and presumably the reticulum of the reticulocyte, is of cytoplasmic rather than nuclear origin.
Activity of Megakaryocytes in the Postoperative State
Authors: KERHULAS A. A. , OHLER ROBERT L. , WARREN RICHARD , BELKO JOHN S. 
Published: October 2019

Abstract
Simultaneous bone marrow smears and platelet counts on the peripheral blood were made preoperatively and on the third and the tenth days after operation in 14 patients. Observations of the activity of the megakaryocytes of the bone marrow on the third day were inconclusive and require further observation. There was, however, a significant increase in activity on the tenth day.
It is postulated that the thrombocytosis which occurs on the tenth postoperative day is the result of increased activity of the megakaryocytes of the bone marrow induced by the attempt of the body to replenish depleted platelet reserves.
Platelet effects on tissue factor and fibrinolytic inhibition of cultured human fibroblasts and vascular cells
Authors: Smariga PE , Maynard JR 
Published: October 2019

Abstract
Platelets stimulate tissue factor, the initiator of the extrinsic coagulation pathway, and increase fibrinolytic inhibition in fibroblasts grown in vitro. Cellular tissue factor increases an average of 2.8-fold over the control levels after a 6-hr incubation with platelets, and no activity is present in the media. Fibrinolytic inhibition is stimulated in both the fibroblasts and their media in the presence of platelets and accumulates throughout a 24-hr incubation. Neither leukocytes nor erythrocytes stimulate these changes. Both tissue factor and fibrinolytic inhibition increases are dependent on platelet concentration and are blocked by inhibitors of RNA or protein synthesis. Control smooth muscle cells have higher tissue factor and fibrinolytic inhibition than fibroblasts, but their response to the presence of platelets is similar. Confluent monolayers of endothelial cells have very low levels of tissue factor that are not altered by the presence of platelets. However, the ability of endothelial cells to inhibit fibrinolysis is enhanced by the presence of platelets. The fraction that stimulates tissue factor and fibrinolytic inhibition is distinct from platelet-derived growth factor and from the fraction that enhances leukocyte tissue factor. It is associated with an insoluble, nonmitogenic fraction that is not inactivated by phospholipase C, or diisopropylfluorophosphate, nor is it chloroform:methanol extractable. Platelets are a physiologic modulator for both cellular tissue factor and the fibrinolytic system in vitro.
Decreased number of circulating BFU-Es in paroxysmal nocturnal hemoglobinuria
Authors: Rotoli B , Robledo R , Luzzatto L 
Published: October 2019

Abstract
In order to quantitate early erythroid progenitor cells in paroxysmal nocturnal hemoglobinuria (PNH), we have cultured peripheral blood mononuclear cells from 7 PNH patients in a 0.8% methylcellulose medium containing erythropoietin, 2 U/ml. In our experimental conditions, the number of erythroid colonies obtained per 5 X 10(5) mononuclear cells plated was 20.1 +/- 1.9 (SEM) in normal subjects and 2.8 +/- 0.56 (SEM) in PNH patients. In plates from PNH subjects, 38 of 117 showed no growth of erythroid colonies, whereas plates from normal subjects always had colonies. Our findings suggest that PNH patients, despite their hemolytic condition, have a depleted erythroid precursor compartment, and this may play a major role in the pathogenesis of their anemia.
Use of asplenic rabbits to demonstrate that platelet age and density are related
Authors: Corash L , Shafer B 
Published: October 2019

Abstract
An experimental model using asplenic rabbits injected with radioactive amino acids has been developed to examine the density distribution of newly released platelets. Platelets from asplenic rabbits had a larger mean volume and greater protein content than those from asplenic animals. Radiolabel, indicative of new platelets, is preferentially incorporated into the most dense platelets during the early postinjection period. Platelets of intermediate density also demonstrated augmented early label incorporation compared to the lightest cells, In contrast, during the late postinjection phase, there is preferential labeling of the least dense platelets. The specific radioactivity of heavy and light platelets rises to approximately equal levels, and falls abruptly, but the peak activities occur at distinctly separate times consistent with the concept of platelet density modification during platelet aging. Although platelet biologic properties are broadly distributed, these studies support the concept that on the average young platelets have an increased density and become less dense as they circulate.
Cell competence for industion of differentiation by insulin and other compounds in myeloid leukemic clones continuously cultured in serum- free medium
Authors: Symonds G , Sachs L 
Published: October 2019

Abstract
Clones of myeloid leukemic cells varying in their competence for induction of differentiation have been continuously grown in serum-free medium. In the medium used, which contained transferrin, the growth rates of these cells were nearly similar to those found in serum- containing medium. The clones also maintained in this medium their competence for induction of differentiation by the normal macrophage and granulocyte differentiation-induction protein MGI-2, the steroid dexamethasone, and lipopolysaccharide. In contrast to the results with these inducters, some clones continuously cultured in a serum-free medium showed a gain of inducibility by insulin and another clone a gain of inducibility by the tumor promoter 12-O-tetradecanoylphorbol-13- acetate in low serum and serum-free medium. Induction of differentiation by these two compounds was therefore inhibited in these clones by the presence of serum. It is suggested that serum-free medium may also show the existence of other inducers of differentiation not detected in serum-containing medium and that these results are relevant to the possible therapeutic use of compounds such as insulin for the induction of normal differentiation in leukemic cells in vivo.
Potentiation of fibroblast growth by nodular sclerosing Hodgkin's disease cell cultures
Authors: Newcom SR , O'Rourke L 
Published: October 2019

Abstract
Cell cultures were established from 8 lymph nodes replaced by nodular sclerosing Hodgkin's disease. Serum-containing and serum-free conditioned media from these cultures potentiated fibroblast growth and were found to be consistently more potent than fibroblast growth factor, 100 ng/ml, every other day. Both a proliferative response and transformation-like growth were observed using BALB/c 3T3 cells, human diploid fibroblasts, and human embryonic fibroblasts as target cells. The Hodgkin's disease growth factor(s) was not produced by fibroblasts or lymphocytes in the Hodgkin's cultures and was most potent when the Hodgkin's cultures had been enriched with Hodgkin's giant cells. Removal of normal macrophages decreased the proliferative activity but did not eliminate it or nonadherent growth of 3T3 cells in agar. Control cultures of 6 nonmalignant lymph nodes, a Lennert's lymphoma, a mixed cellularity Hodgkin's disease lymph node, and a malignant histiocytosis cell line suggested that among lymph node disorders, this feature may be relatively specific for nodular sclerosing Hodgkin's disease.
Purification of colony-stimulating factor by affinity chromatography
Authors: Waheed A , Shadduck RK 
Published: October 2019

Abstract
Studies were undertaken to determine whether L-cell-derived colony-stimulating factor (CSF) could be purified by a single step affinity chromatographic technique. A quantity of 100 X 10(6) units of purified anti-CSF was coupled to cyanogen bromide activated Sepharose 4B; colony assays revealed complete binding of the antibodies to the gel. Three 10- liter pools of serum-free L-cell CSF were concentrated by ultrafiltration, applied to the gel, and eluted with a low pH, high molarity buffer. Recovery of CSF ranged from 68%-100% with greater than 1000-fold decreases in protein content. Specific activity of the purified CSF ranged from 2.8 to 5.9 X 10(7) U of CSF/mg protein. Following iodination, each purified pool of CSF revealed a major 63,000- dalton peak of radioactivity that comigrated with CSF activity in SDS- acrylamide gels. In addition, several smaller peaks of 50,000 and 40,000 molecular weight were also detected. Approximately two-thirds of the purified CSF was adherent to concanavalin-A with elution by a competing sugar. Electrophoretic mobility was retarded by incubation with neuraminidase. These chromatographic studies confirm the observation that CSF is a glycoprotein but also suggest variable degrees of glycosylation of the molecule. This chromatographic technique should prove useful in the rapid purification of large quantities of CSF for physiologic and biochemical characterization.