bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spectrin beta Tandil, a novel shortened beta-chain variant associated with hereditary elliptocytosis is due to a deletional frameshift mutation in the beta-spectrin gene
Authors: Garbarz M , Boulanger L , Pedroni S , Lecomte MC , Gautero H , Galand C , Boivin P , Feldman L , Dhermy D 
Published: October 2019

Abstract
An Argentinian family with hereditary elliptocytosis (HE) associated with a shortened beta-spectrin (Sp) chain was studied. As with most of the other shortened Sp beta-chains that have been described, this variant, called SpTandil, has impaired ability to participate in Sp dimer self-association, has lost its ability to become phosphorylated, and is associated with the presence of increased amounts of the alpha I 74-Kd fragment after partial tryptic digestion of Sp. The 3′ ends of the beta-Sp gene of affected patients were analyzed. cDNA was prepared by reverse transcription of peripheral blood mRNA and amplified by the polymerase chain reaction (PCR) using primers corresponding to sequences 400 bp apart on the cDNA, spanning the last three exons (X, Y, Z) of the beta-Sp gene. Agarose gel electrophoresis of the cDNA amplification showed the presence of one band, the size of which was apparently the same as the band amplified from mRNA of a normal control. cDNA from one HE patient was subcloned and sequenced. Several clones showed the presence of a 7-bp deletion at codon 2041 in exon X. Genomic DNA of all the affected members of the family were amplified by PCR using primers flanking the deletion and corresponding to sequences 128 bp apart on exon X. Analysis of the PCR products using electrophoresis on polyacrylamide gel showed the presence of 121- and 128-bp bands in all HE subjects, and an additional doublet migrating more slowly than the two bands, which corresponded to the presence of heteroduplexes. The mutation results in a shift of the normal reading frame and leads to a new amino acid sequence at the C-terminus of the mutant beta-Sp chain. A new in-frame stop codon is encountered downstream, leading to premature chain termination. The identification of the molecular defect in Sp beta Tandil provides information regarding the region of the beta-Sp chain that is important for both Sp dimer self-association and an indication of potential sites of phosphorylation of the chain.
Bone marrows of non-Hodgkin's lymphoma patients with a bcl-2 translocation can be purged of polymerase chain reaction-detectable lymphoma cells using monoclonal antibodies and immunomagnetic bead depletion
Authors: Gribben JG , Saporito L , Barber M , Blake KW , Edwards RM , Griffin JD , Freedman AS , Nadler LM 
Published: October 2019

Abstract
Using the extremely sensitive technique of polymerase chain reaction (PCR) to detect the bcl-2 translocation, only 50% of bone marrows could be purged of PCR-detectable lymphoma cells using a cocktail of three anti-B-cell monoclonal antibodies (MoAbs) and complement-mediated lysis. This observation is of clinical importance because those patients whose reinfused marrows harbored residual lymphoma cells showed a significantly increased incidence of relapse. To improve purging, we used PCR detection of the bcl-2 translocation to compare the efficiency of complement-mediated lysis with immunomagnetic bead depletion. Using either a three or a four MoAb cocktail followed by immunomagnetic bead depletion, all PCR-detectable cells were purged after three cycles of treatment. In these same patient samples, treatment with three MoAbs and complement purged only 11 of the 25 (44%) samples. The addition of a fourth MoAb followed by complement lysis purged the marrows of only an additional five patients. Immunomagnetic bead depletion was specific because there was no loss of committed myeloid progenitor cells. The above results suggest that immunomagnetic bead depletion of the harvested marrow will likely be superior to our previous method of purging and the lack of nonspecific toxicity to myeloid progenitor cells predicts that it will not impair engraftment. This methodology will now be used to determine whether the reinfusion of lymphoma free marrow affects the incidence of relapse after autologous bone marrow transplantation.
Effects of actin filaments on fibrin clot structure and lysis
Authors: Janmey PA , Lamb JA , Ezzell RM , Hvidt S , Lind SE 
Published: October 2019

Abstract
The muscle and cytoskeletal protein actin is released from cells as a consequence of cell death and interacts with components of the hemostatic and fibrinolytic systems, including platelets, plasmin, and fibrin. We report here that incorporation of actin filaments into fibrin clots changes their viscoelastic properties by increasing their shear modulus at low deforming stresses and by nearly eliminating their tendency to become more rigid with increasing deformation (ie, exhibit strain-hardening). The viscoelastic effects depended on the length of the actin filaments as shown by the effects of the plasma filament- severing protein, gelsolin. Binding of actin to fibrin clots also varied with actin filament length. The plasma actin-binding proteins gelsolin and vitamin D-binding protein reduced, but did not eliminate, the incorporation of actin in the clot. Fluorescence microscopy showed a direct association of rhodamine-labeled actin filaments with the fibrin network. Incubation of clots containing long actin filaments in solutions containing physiologic concentrations of gelsolin (2 mumol/L) released 60% of the actin trapped in the clot. Reduction of the actin content of a fibrin clot by incubation in a gelsolin-containing solution resulted in an increased rate of clot lysis. The ability of plasma gelsolin to shorten actin filaments may therefore be of physiologic and potentially of therapeutic importance insofar as gelsolin-mediated diffusion of actin from the clot may restore the clot's rheologic properties and render it more sensitive to the lytic action of plasmin.
Role of plasma viscosity in platelet adhesion
Authors: van Breugel HF , de Groot PG , Heethaar RM , Sixma JJ 
Published: October 2019

Abstract
Platelet adhesion to the vessel wall is initiated by transport of blood platelets from the bulk flow to the wall. The process of diffusion and convection of the platelets is affected by rheological conditions such as well shear rate, red blood cell (RBC) deformability, and viscosity of the medium. To study the effect of plasma viscosity on platelet adhesion, perfusion experiments with a rectangular perfusion chamber were performed. Reconstituted blood, consisting of washed platelets and washed RBCs, was circulated through this chamber for 5 minutes at a wall shear rate of 300 s-1. Different albumin concentrations were made, to obtain different medium viscosities (0.89 to 1.85 mPa.s). Platelet adhesion decreased with increasing medium viscosity up to viscosities of 0.95 mPa.s, but increased with medium viscosity above this value. Instead of human albumin solution, different plasma viscosities were obtained by dilution of Waldenstrom plasma with buffer. Plasma was depleted of fibronectin, which gave a final plasma viscosity of 2.0 mPa.s, and was dialyzed against HEPES buffer and subsequently diluted with the dialysis buffer in different fractions (0.89 to 2.00 mPa.s). Perfusions were performed over a purified von Willebrand factor coating on glass, or over an endothelial cell matrix, preincubated with von Willebrand factor. With both surfaces, platelet adhesion was dependent on the plasma viscosity in a similar way: at low plasma viscosities, adhesion was decreased with increasing plasma viscosity, while at higher plasma viscosities, adhesion increased with plasma viscosity. Adhesion values at higher plasma viscosity or at higher human albumin concentrations could be explained by effects of the medium on the rigidity of the RBCs, since platelet adhesion is known to be increased by enhanced RBC rigidity. Effects of the medium on the deformability of the RBCs were measured separately with the laser diffraction method. These experiments confirmed that presence of human albumin or plasma in the measuring suspension increased the rigidity of RBCs. To prevent influence of the medium on the RBCs in perfusion experiments, the RBCs were fixated with glutaraldehyde. Perfusion experiments with fixated RBCs in plasma over a von Willebrand factor preincubated endothelial cell matrix, showed a consequent decrease in adhesion with increasing plasma viscosity, according to the diffusion theories, whereas the increase of adhesion at high plasma viscosities was lacking. This suggests that the latter effect was entirely due to increased transport of platelets by more rigid RBCs.
Relationship of antiphospholipid antibodies to pregnancy loss in patients with systemic lupus erythematosus: a cross-sectional study [see comments]
Authors: Ginsberg JS , Brill-Edwards P , Johnston M , Denburg JA , Andrew M , Burrows RF , Bensen W , Cividino A , Long AA 
Published: October 2019

Abstract
To determine whether an association exists between the presence of antiphospholipid antibodies and pregnancy loss, a cross-sectional study was performed. Consecutive women who were referred to three outpatient rheumatology clinics and who had systemic lupus erythematosus (SLE) and a history of one or more pregnancies were evaluated. Patients were interviewed to determine outcomes of all previous pregnancies. Blood was taken on two separate occasions at least 3 months apart to test for the presence of the lupus anticoagulant and anticardiolipin antibodies; on both occasions, five tests of the lupus anticoagulant, with well- defined normal ranges, and an enzyme-linked immunosorbent assay to measure IgG anticardiolipin antibodies were performed. Patients were considered to be positive for the lupus anticoagulant if one or more tests was abnormal on both occasions and positive for anticardiolipin antibodies if the test was abnormal on both occasions. Forty-two women were studied. Statistically significant associations were shown between lupus anticoagulant positivity and previous pregnancy loss (odds ratio [OR], 4.8; 95% confidence intervals [CI], 1.0 to 23.6; P = .05) and between anticardiolipin antibody positivity and previous pregnancy loss (OR, 20.0; 95% CI, 1.3 to 97.0; P = .01). All seven women with multiple episodes of pregnancy loss were lupus anticoagulant positive and four of these were also anticardiolipin antibody positive. If patients who are transiently positive for lupus anticoagulant and/or anticardiolipin antibodies are considered to be test positive, the associations with pregnancy loss are no longer statistically significant. Within the group of lupus anticoagulant-positive patients, we observed stronger associations between the presence of six or more positive tests and pregnancy loss than between the presence of two to five positive tests and pregnancy loss. No single test for the lupus anticoagulant provides a statistically significant association with pregnancy loss. The results of our study show that by performing multiple lupus anticoagulant tests and by repeating testing for lupus anticoagulant and anticardiolipin antibodies on more than one occasion, significant associations between the presence of antiphospholipid antibodies and previous pregnancy loss can be shown in patients with SLE.
Stimulation of tissue plasminogen activator production by retinoic acid: synergistic effect on protein kinase C-mediated activation
Authors: Medh RD , Santell L , Levin EG 
Published: October 2019

Abstract
Trans retinoic acid (t-RA) stimulated the production of tissue plasminogen activator (tPA) in HeLa-S3 and human umbilical vein endothelial cells (huvecs) in a dose-dependent manner with maximal release (four to five times control) at 40 nmol/L and 40 mumol/L, respectively. In endothelial cells, the stimulation of tPA production by phorbol 12-myristate 13-acetate (PMA) was potentiated 1.9-fold by 10 mumol/L t-RA, or 1.8 times the additive effect. In HeLa cells, total tPA secretion with 10 nmol/L PMA was increased from 43 ng/mL to 96 ng/mL by 40 nmol/L t-RA, which was two times the additive effect. Higher concentrations of t-RA (400 nmol/L) depressed tPA secretion by itself and also suppressed PMA-induced tPA production by 50%. Histamine and thrombin also synergized with t-RA. t-RA (40 nmol/L) and 10 micrograms/mL histamine or 10 U/mL thrombin combined to induce tPA production 3.4 and 1.3 times the additive effect in HeLa cells. Cyclic adenosine monophosphate (cAMP) levels were not significantly affected by 10 nmol/L to 10 mumol/L t-RA. Nor did 10 nmol/L PMA and 40 nmol/L t- RA together affect cAMP levels, suggesting that t-RA-mediated potentiation of PMA-induced tPA production occurred via a mechanism that was independent of cAMP levels. Downregulation of protein kinase C (PKC) by pretreatment of huvecs with 100 nmol/L PMA completely blocked a secondary response to PMA, but did not have a significant effect on t- RA induction. Pretreatment with 10 mumol/L t-RA, on the other hand, did not significantly affect a secondary stimulus by 100 nmol/L PMA, but completely suppressed a secondary stimulation by 10 mumol/L t-RA alone. These studies suggest that the mechanism mediating t-RA stimulation of tPA production interacts with the PKC pathway, resulting in synergism.
High-dose chemoradiotherapy followed by autologous bone marrow transplantation as consolidation therapy during first complete remission in adult patients with poor-risk aggressive lymphoma: a pilot study [see comments]
Authors: Nademanee A , Schmidt GM , O'Donnell MR , Snyder DS , Parker PA , Stein A , Smith E , Lipsett JA , Sniecinski I , Margolin K 
Published: October 2019

Abstract
Twenty consecutive patients with poor-risk aggressive lymphoma who at presentation either had elevated serum lactic dehydrogenase level (LDH) and any one of the other poor-prognostic features: bulky mass greater than or equal to 10 cm, advanced stage III or IV, and greater than or equal to 2 extranodal sites, or normal LDH level and all other three features, underwent high-dose chemo/radiotherapy followed by unmanipulated autologous bone marrow transplantation (BMT) during their first complete remission. Eighteen had B-cell lymphoma and 2 had T-cell lymphoma. Eleven patients had high-grade (7 immunoblastic, 3 small noncleaved, non-Burkitt's, and 1 Burkitt's) and 9 had diffuse large cell lymphoma. All patients had achieved a complete remission following conventional chemotherapy. Four patients had also received involved field radiotherapy to areas of bulky disease. The preparative regimen consisted of high-dose etoposide 60 mg/kg and cyclophosphamide 100 mg/kg in combination with fractionated total body irradiation (FTBI) 1,200 cGy (15 patients), or single-dose TBI 750 cGy (2 patients), or carmustine 450 mg/m2 (3 patients). All patients tolerated the treatment well and achieved complete hematologic recovery. Three patients have relapsed at days 79, 196, and 401 after transplantation. Seventeen patients (84%) are alive and relapse-free with a median follow-up of 34 months (range 2 to 54). We conclude that high-dose chemo/radiotherapy followed by autologous BMT can be given as consolidation therapy during first remission in these patients with minimal transplant-related toxicity.
Recombinant human granulocyte-macrophage colony-stimulating factor after high-dose chemotherapy and autologous bone marrow transplantation with unpurged and purged marrow in non-Hodgkin's lymphoma: a double- blind placebo-controlled trial
Authors: Gorin NC , Coiffier B , Hayat M , Fouillard L , Kuentz M , Flesch M , Colombat P , Boivin P , Slavin S , Philip T 
Published: October 2019

Abstract
The toxicity of autologous bone marrow transplantation (ABMT) is correlated to neutropenia. Although recombinant human granulocyte- macrophage colony-stimulating factor (rhu GM-CSF) seems to hold promise in accelerating neutrophil recovery, few analyses from randomized studies are presently available. Ninety-one patients with non-Hodgkin's lymphoma receiving high-dose ablative chemotherapy followed by ABMT with unpurged or purged marrow were included in a randomized, double- blind, placebo-controlled trial. Forty-four patients received 250 micrograms rhu GM-CSF (Escherichia coli)/m2 and 47 patients received placebo. Treatment was administered daily as continuous infusion from day of ABMT until the absolute neutrophil count (ANC) reached 0.5 x 10(9)/L for 7 days or until day 30, whichever was first. With rhu GM- CSF, 50% of the patients reached an ANC count greater than 0.5 x 10(9)/L at day 14 as opposed to day 21 with placebo (P less than .0001). Patients transplanted with marrow purged by mafosfamide also recovered earlier when treated with rhu GM-CSF (16 v 20.5 days, P = .013). The hospitalization duration was shorter in the rhu GM-CSF group (median, 23 v 28 days, P less than .05). No difference was observed in fever, number of infections, and antibiotic administration between the two groups. The major adverse event ascribed to rhu GM-CSF was a capillary leak syndrome in three patients graded as severe in two patients, moderate in one, and reversible in all three patients. In addition, one patient in the rhu GM-CSF group died suddenly with no explanation. In long term follow-up, the relapse rate was identical in both groups and there was no significant difference in the number of deaths at 1 year (12 with rhu GM-CSF v 9 with placebo), although deaths seemed to occur slightly earlier in the rhu GM-CSF group. We conclude that after ABMT with purged or unpurged marrow, rhu GM-CSF (E coli) significantly reduces neutropenia duration and hospitalization stay. A positive causative relation between the study drug and/or its mode of application with an increased toxicity as compared with GM-CSF from other sources and/or other modes of application cannot be deduced from the experiences in this study. Additional randomized trials would be necessary for an appropriate answer.
Antibody responses to bacteriophage phi X174 in patients with adenosine deaminase deficiency
Authors: Ochs HD , Buckley RH , Kobayashi RH , Kobayashi AL , Sorensen RU , Douglas SD , Hamilton BL , Hershfield MS 
Published: October 2019

Abstract
Adenosine deaminase (ADA) deficiency and its biochemical consequences cause severe combined immunodeficiency (SCID). Treatment strategies, designed to correct the biochemical abnormalities, include transplantation of matched bone marrow or haploidentical bone marrow stem cells, repeated partial exchange transfusions with frozen irradiated human red blood cells (RBC), or weekly injection of polyethylene glycol-modified bovine ADA (PEG-ADA). To evaluate the effect of these therapeutic options, we studied in vitro T-cell function and in vivo antibody responses to the T-cell-dependent neoantigen, bacteriophage phi X174, in 10 children with ADA-deficient SCID. In untreated patients, T-cell function was severely depressed, and only minute amounts of antibacteriophage antibody were produced. Transplantation of bone marrow from a matched sibling (one patient) or a phenotypically matched parent (one patient) resulted in a stable graft, normal T-cell function, and substantial but subnormal antibody titers to bacteriophage, with reduced memory and impaired switch from IgM to IgG. Patients receiving T-cell-depleted haploidentical bone marrow stem cells had markedly depressed antibody responses for as long as 3 years posttransplantation, despite rapidly improving T-cell function that became normal in two of four patients. Two methods of enzyme replacement were explored. During treatment with human RBC transfusions, antibody responses to bacteriophage were as severely depressed as in untreated ADA-deficient patients. Treatment with weekly injections of PEG-ADA resulted in normalization of T-cell numbers in all four patients, normal or near-normal T-cell function in two, and mildly but variably improved T-cell function in the other two patients. Quantitatively and qualitatively normal antibody responses to bacteriophage were observed in three of four patients. Assessment of antibody responses to immunization with bacteriophage phi X174 is a useful method to monitor humoral immune function in treated ADA- deficient patients and can be used to estimate when intravenous immunoglobulin (IVIG) prophylaxis may be safely discontinued.
Effect of adrenergic agents on hematopoiesis after syngeneic bone marrow transplantation in mice
Authors: Maestroni GJ , Conti A , Pedrinis E 
Published: October 2019

Abstract
We show that adrenergic agents modulate hematopoietic reconstitution after syngeneic bone marrow transplantation (BMT) in mice. Chemical sympathectomy by 6-hydroxydopamine (6-OHDA) significantly increased the number of peripheral blood leukocytes after syngeneic BMT. The alpha 1- adrenergic antagonist prazosin mimicked and extended the effect of 6- OHDA, with an additional rapid and significant increase of platelets, marrow granulocyte-macrophage colony-forming units, and nucleated spleen cells. Differential leukocyte counts and spleen histology from prazosin-treated mice confirmed that myelopoiesis was greatly enhanced and accelerated. In contrast, the beta-adrenergic blocker propranolol abolished the prazosin-induced increase of platelets. The detailed mechanisms by which prazosin exerts these interesting effects remain to be elucidated.
Interleukin-11 stimulates multiple phases of erythropoiesis in vitro
Authors: Quesniaux VF , Clark SC , Turner K , Fagg B 
Published: October 2019

Abstract
Interleukin-11 (IL-11), a pleiotropic cytokine originally isolated from a primate bone marrow stromal cell line, has been shown to stimulate T- cell-dependent B-cell maturation, megakaryopoiesis, and various stages of myeloid differentiation, but to inhibit adipogenesis. Because stromal cells are essential for the maintenance of early hematopoietic progenitor cells in long-term culture, we investigated the effects of IL-11 on multipotent and erythroid precursors from murine bone marrow in vitro in suspension and semisolid cultures. Our results show that in the presence of IL-3 or c-kit ligand (KL), IL-11 has profound stimulatory effects on primitive multilineage hematopoietic progenitors, pre-CFC(multi), as well as on precursors representing various stages of erythroid differentiation observable in vitro, including CFC(multi), BFU-E, and CFU-E. In addition, the combination of KL with IL-11 also stimulated highly proliferative erythroid progenitors that yield remarkable macroscopic erythroblast colonies in culture. These results indicate that IL-11 is likely to play a pivotal role in early hematopoiesis and at multiple stages of erythropoiesis.
Growth and spread of human malignant T lymphoblasts in immunosuppressed nude mice: a model for meningeal leukemia
Authors: Cavallo F , Forni M , Riccardi C , Soleti A , Di Pierro F , Forni G 
Published: October 2019

Abstract
Previous work has shown that nude (nu/nu) mice additionally immunosuppressed by splenectomy, sublethal irradiation, and treatment with antiasialo GM1 antiserum (SIA-nu/nu mice) have no detectable natural killer activity and allow the growth of human malignant lymphoblasts. We show here that all SIA-nu/nu mice engrafted intravenously with 5 x 10(6) malignant lymphoblasts originally derived from a child with a T-cell acute lymphoblastic leukemia (PF382) and from a boy with a T-cell lymphoma (ST-4) develop lethal meningeal leukemia and die within 35 days. Histologic examination of moribund SIA- nu/nu mice showed that vertebral and skull bone marrow was always replaced by proliferating human T lymphoblasts. From the spinal canal, lymphoblasts spread to the meninges, causing hind leg paralysis. Leaving the skull, they permeated the meninges and then invaded the nervous parenchyma. This efficient and reproducible experimental model may be suitable for experimental studies on the pathogenesis of meningeal leukemia.