bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adsorption and conversion of prothrombin on a rotating disc
Authors: Willems GM , Giesen PL , Hermens WT 
Published: October 2019

Abstract
In most flow systems, the rate of protein transfer from bulk solution to a macroscopic surface is site-dependent. In studies on surface- mediated protein conversion, this hampers the comparison of a proposed expression for the conversion process, such as the Michaelis-Menten equation, which actually measured overall conversion rates. However, the rotating disc is a classical example of a uniformly accessible surface and therefore was used for a quantitative analysis of prothrombin conversion by the phospholipid-bound factor Xa/factor Va complex (prothrombinase complex). A simple design of a rotating disc, adapted for ellipsometric measurement of protein adsorption, is presented. Agreement between experiment and theory was obtained for the influence of rotation velocity on the initial, transport-limited, adsorption rates of lysozyme, prothrombin, and fibrinogen. After coverage of the disc with a 20% phosphatidylserine/80% phosphatidylcholine bilayer and preadsorption of factor Va, addition of excess factor Xa and prothrombin resulted in effective conversion of prothrombin. For high (10 fmol.cm-2) surface coverage of prothrombinase, the rate of conversion equals the transport limited adsorption rate of prothrombin. For low (0.1 to 0.5 fmol.cm-2) surface concentrations of prothrombinase, the conversion rate dropped below the transport limit and the intrinsic kinetic parameters could be estimated at Km = 7.1 +/- 1.2 nM and kcat = 25 +/- 1.0 s-1 (20 degrees C). At these low surface activities of prothrombinase, the effect of the rotation rate (6 to 225 rad.s-1) on prothrombin conversion could be explained by the rotation-rate dependent prothrombin transport. This indicates that the fluid shear rate has no drastic influence on the intrinsic kinetics of prothrombin conversion.
Distinct ongoing Ig heavy chain rearrangement processes in childhood B- precursor acute lymphoblastic leukemia
Authors: Steenbergen EJ , Verhagen OJ , van Leeuwen EF , von dem Borne AE , van der Schoot CE 
Published: October 2019

Abstract
Acute lymphoblastic leukemia (ALL) is thought to arise from the clonal expansion of a single transformed precursor cell. However, an oligoclonal Ig heavy chain (IgH) rearrangement pattern has been observed in 30% of ALL patients and was shown to be the result of ongoing rearrangement events. The extent and nature of these ongoing rearrangement processes in individual patients has so far remained obscure. We performed a detailed analysis of leukemic VHDJH rearrangements in three children with B-precursor ALL at diagnosis and one B-lymphoid blast crisis of a child with Ph+ chronic myeloid leukemia at diagnosis and relapse. The children were selected because they presented with multiple IgH rearrangements on Southern blot analysis. Polymerase chain reaction analysis of leukemic cells from two B-precursor ALL patients showed exclusively two groups of related sequences resulting from VH gene replacement events. Most VH gene replacements involved 3′ located acceptor VH genes. Analysis of cells from the other B-precursor ALL patient showed exclusively related sequences as a result of VH gene joinings to a pre-existing DJH rearrangement. In the B-lymphoid blast crisis, a single germline precursor cell had generated multiple unrelated rearrangements and additional groups of related rearrangements resulting from VH to DJH joinings. Direct proof for the VH to DJH joining mechanism was obtained by amplification of the expected preexisting DJH rearrangements. Our findings suggest that the pattern of ongoing rearrangements in an individual patient reflects the IgH rearrangement status of the precursor cell at the time of malignant transformation. Sequence analysis of VHDJH rearrangements at diagnosis may therefore allow a prediction of the reliability of complementarity determining region 3 probes for the detection of minimal residual disease.
Characterization of cells emerging at the time of graft failure after bone marrow transplantation from an unrelated marrow donor
Authors: Donohue J , Homge M , Kernan NA 
Published: October 2019

Abstract
To help elucidate the mechanism responsible for graft failure (GF) following a T-cell depleted bone marrow transplant (BMT) from an unrelated donor, five patients (2 chronic myelogenous leukemia, 1 acute undifferentiated leukemia, 2 myelodysplastic syndrome) who experienced this complication were studied. All patients were HLA class I identical with their donors as determined by serology and one-dimensional isoelectric focusing (IEF); two were serologically matched with their donors for HLA class II antigens, whereas three donor-recipient pairs were serologically mismatched for one HLA-DR antigen. All patients received total body irradiation (fractionated, 1,500 rads), VP-16 (750 mg/m2), and cyclophosphamide (120 mg/kg) pre-BMT and antithymocyte globulin (15 mg/kg every other day) and methylprednisolone (2 mg/kg) post-BMT. Three patients experienced primary nonengraftment and two experienced secondary GF. Peripheral blood mononuclear cells obtained from the patients at the time of GF were studied to examine their functional and phenotypic characteristics. Emerging cells were of host origin and were found to be specifically cytotoxic to donor target cells and suppressive to the in vitro growth of donor BM, especially in the cases of primary nonengraftment. Peripheral blood mononuclear cells from these patients were expanded to form T-cell lines (TcLs). The cytotoxic activities of TcLs were tested in the presence of blocking MoAbs directed against various HLA determinants in an attempt to determine if HLA antigens expressed on donor cells were the target for cytotoxicity. The observed cytotoxic activity was blocked by antibodies to HLA-B, -C (1 patient), HLA-DR (1 patient), and HLA-DQ (1 patient). In two cases, antidonor cytotoxicity could not be blocked by MoAb directed against HLA-A, -B, -C, or -DR. Phenotypic characterization of four successfully maintained TcLs showed 100% CD3+ cells with 100% CD4+ (3 patients) or 50% CD4+/50% CD8+ (1 patient). In two of the three patients with 100% CD4+ cells, antidonor cytotoxicity was blocked by an anti-HLA class II MoAb. In contrast to our previous findings in cases of GF following T-cell-depleted HLA nonidentical family member BMT in which host T cells were CD8+ and cytotoxicity was directed against HLA class I antigens, our present study indicates host T cells emerging at the time of GF following BMT from an HLA class I IEF-identical unrelated donor can be of the CD4+ subset and seem to be capable of recognizing antigenic disparities in the HLA class II region.
Identification of yeast artificial chromosomes containing the inversion 16 p-arm breakpoint associated with acute myelomonocytic leukemia
Authors: Liu P , Claxton DF , Marlton P , Hajra A , Siciliano J , Freedman M , Chandrasekharappa SC , Yanagisawa K , Stallings RL , Collins FS 
Published: October 2019

Abstract
We report the cloning of the chromosome 16 p-arm breakpoint involved in inversion 16(p13;q22) associated with subtype of acute myelomonocytic leukemia (AMML) M4Eo. Inter-Alu polymerase chain reaction (PCR) products from a series of interspecific somatic cell hybrids that contain only small portions of the human chromosome 16 p-arm were generated for use as fluorescent in-situ hybridization (FISH) probes. When applied to patient cells, rapid and unambiguous identification of the inversion resulted. Using FISH analysis, cosmid clones associated with the hybrids were identified that bracketed the p-arm breakpoint. A repeat-free fragment of one of these cosmids (35B11) when used as probe on Southern blots from pulsed-field gels identified rearranged macrorestriction fragments in patient DNA. Yeast artificial chromosomes (YACs) were isolated using sequences derived from cosmids flanking 35B11 in a cosmid contig. Of 4 YACs so identified, 3 were shown by FISH to cross the inversion-16 p-arm breakpoint. Therefore, the breakpoint has been molecularly cloned, and identified as being within these 3 YACs. These clones will facilitate the unraveling of the genetic events associated with inversion-16 and are available tools with immediate clinical application.
Prevention of regimen-related toxicities after bone marrow transplantation by pentoxifylline: a prospective, randomized trial
Authors: Attal M , Huguet F , Rubie H , Charlet JP , Schlaifer D , Huynh A , Laurent G , Pris J 
Published: October 2019

Abstract
Elevated levels of tumor necrosis factor alpha (TNF-alpha) have been reported to correlate with the development of transplant-related complications after bone marrow transplantation (BMT). In a recent phase I-II trial, oral administration of pentoxifylline (PTX), a xanthine derivative capable of downregulating TNF-alpha production in vitro, was reported to reduce morbidity and mortality in patients undergoing BMT. We conducted a prospective randomized trial of PTX therapy among 140 patients undergoing either allogeneic (n = 51) or autologous BMT (n = 89). Patients were randomized to receive (n = 70) or not receive (n = 70) oral PTX, 1,600 mg/d in four divided doses from day -8 until day + 100 post-BMT. The incidence of mucositis requiring morphine sulfate (MSO4) was similar in both groups (42.9%), with the mean number of days with MSO4 being 7.8 (SD = 3.4) in the PTX group versus 8.2 (SD = 3.4) in the control group (NS). The incidence of renal insufficiency was not affected by PTX administration (15.7% in the PTX group v 21.4% in the control group [NS]) and the highest serum creatinine value during the first 100 days post-BMT was 119 mumol/L (SD = 82.4) in the PTX group versus 103.9 mumol/L (SD = 57) in the control group (NS). The incidence of grade > or = 2 graft-versus-host disease was similar in each group (11/25 [44%] in the PTX group v 12/26 [46%] in the control group). No significant difference was observed in hematologic toxicity, transfusion requirements, duration of fever, and hepatic toxicity between the treatment groups. In conclusion, our study failed to show a prophylactic effect of PTX in transplant-related toxicities after BMT. On the basis of these findings, we cannot recommend that PTX be part of early mortality and morbidity prevention programs after BMT.
Demonstration of Epstein-Barr virus replication in Reed-Sternberg cells of Hodgkin's disease
Authors: Brousset P , Knecht H , Rubin B , Drouet E , Chittal S , Meggetto F , Saati TA , Bachmann E , Denoyel G , Sergeant A 
Published: October 2019

Abstract
Epstein-Barr virus (EBV) is detectable in approximately 40% of cases of Hodgkin's disease (HD). The viral genomes remain latent but positive staining with anti-ZEBRA antibody in a small fraction of Reed-Sternberg (RS) cells of some cases of HD would suggest possible activation of EBV replication within these cells. We report the investigation of 40 cases of EBV-associated HD (including 5 human immunodeficiency virus [HIV]- positive cases) using anti-ZEBRA antibodies. Positive staining was found in only three (HIV-negative) cases. One of these three cases showed approximately 1% of ZEBRA-positive tumor cells, whereas the other two cases showed rare positive cells. In the case with 1% ZEBRA- positive cells, a strong signal was obtained with anti-EA-R antibody and BHLF1 oligoprobes, which indicated early gene expression. EBV replication could be shown in this case by nonisotopic in situ DNA-DNA hybridization, which showed markedly increased numbers of EBV genomes in a few RS cells. Viral replication was confirmed using reverse transcriptase and polymerase chain reaction that detected transcripts from the BLLF1 gene encoding for the membrane antigen gp350/220. EBV replication in RS cells seems to be an exceptional event but may provide clues to mechanisms of control of viral latency and assume clinical implications in the future.
Mutation and protein expression of p53 in acquired immunodeficiency syndrome-related lymphomas
Authors: Nakamura H , Said JW , Miller CW , Koeffler HP 
Published: October 2019

Abstract
p53 mutations are found in a variety of neoplasia. B-immunoblastic lymphoma (BIBL) is a rapidly progressive, aggressive lymphoma. As patients with acquired immunodeficiency syndrome (AIDS) live longer, BIBL is becoming an increasing problem. We asked three questions in our study. What is the frequency of p53 mutations in BIBL? Is it more frequent in patients with AIDS? Can immunohistochemical staining of lymph nodes for expression of p53 substitute for mutational analysis of p53 to detect lymphomas with mutated p53? Exons 5, 6, 7, 8 of the p53 gene (hot-spots for mutations) were amplified and examined for mutations by single-strand conformation polymorphism (SSCP) analysis. Altered migration was observed in 7 of 52 BIBL samples. Of these, 4 of 25 were from individuals infected with human immunodeficiency virus (HIV) and 3 of 27 were not infected with HIV. Direct sequencing of amplified material confirmed the presence of mutations in exons 5, 7, 8 of p53. A total of 26 BIBL as well as other lymphoma/leukemia samples, stained strongly by immunohistochemistry with three antibodies directed against human p53. Five of 6 BIBL samples with p53 mutations stained strongly for p53, but 20 lymphoma samples with no detectable p53 mutations also stained strongly for p53. Of note, however, 10 hyperplastic, nonmalignant lymph nodes from individuals either infected or not infected with HIV had negligible staining for p53 protein. In conclusion, p53 mutations occur in about 14% BIBL samples; the frequency of p53 mutations in BIBL in individuals with and without AIDS was similar. Positive p53 immunohistochemistry did not correlate with detectable p53 mutations in the same tissue, but positive immunohistochemical staining for p53 was only found in neoplastic lymph nodes. This latter finding provides a strong warning that p53 immunochemistry with available reagents cannot be used to determine which tumors have mutations of p53.
Beta-thalassemia unlinked to the beta-globin gene in an English family
Authors: Thein SL , Wood WG , Wickramasinghe SN , Galvin MC 
Published: October 2019

Abstract
An inherited hypochromic microcytic anemia transmitted in an autosomal manner has been observed in three generations of an English family. Affected members had the hallmarks of heterozygous beta-thalassemia, ie, elevated levels of hemoglobin A2 and imbalanced globin chain synthesis. However, despite extensive sequence analysis, no mutations could be found in or around the beta-globin genes of either the propositus or two other affected members from two different generations. Linkage analysis using restriction fragment length polymorphisms in the beta-globin gene cluster clearly showed that the gene responsible for the beta-thalassemia phenotype segregates independently of the beta-gene complex. Therefore, this condition represents a novel form of the disease.
Complement-induced vesiculation and exposure of membrane prothrombinase sites in platelets of paroxysmal nocturnal hemoglobinuria
Authors: Wiedmer T , Hall SE , Ortel TL , Kane WH , Rosse WF , Sims PJ 
Published: October 2019

Abstract
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired stem-cell disorder in which the glycolipid-anchored membrane proteins, including the cell-surface complement inhibitors, CD55 and CD59, are partially or completely deleted from the plasma membranes of mature blood cells. To gain insight into the pathogenesis of thrombosis that is frequently observed in this disorder, the procoagulant responses of PNH platelets exposed to the human terminal complement proteins C5b-9 were investigated. C5b-9 complexes were assembled on gel-filtered platelets by incubation with purified C5b6, C7, C9, and limiting amounts of C8. Platelet microparticle formation and exposure of plasma membrane- binding sites for coagulation factor Va were then analyzed by flow cytometry. PNH platelets exhibiting undetectable levels of surface CD59 antigen showed an approximately 10-fold increase in sensitivity to C5b- 9-stimulated expression of membrane-binding sites for factor Va when compared with platelets from normal controls. Expression of catalytic surface for the prothrombinase complex (VaXa) paralleled the exposure of factor Va-binding sites; the rate of prothrombin conversion by C5b-9- treated PNH platelets exceeded that of C5b-9-treated normal controls by approximately 10-fold at the maximal input of C8 tested (500 ng/mL). These data indicate that PNH platelets deficient in plasma membrane CD59 antigen are exquisitely sensitive to C5b-9-induced expression of prothrombinase activity, and suggest that the tendency toward thrombosis in these patients may be due, at least in part, to the deletion of this complement inhibitor from the platelet plasma membrane.
Effect on lymphocyte subsets of clotting factor therapy in human immunodeficiency virus-1-negative congenital clotting disorders. The Transfusion Safety Study Group
Authors: Hassett J , Gjerset GF , Mosley JW , Fletcher MA , Donegan E , Parker JW , Counts RB , Aledort LM , Lee H , Pike MC 
Published: October 2019

Abstract
Patients with hemophilia A without human immunodeficiency virus type 1 (HIV-1) infection have lower CD4+ counts and CD4+/CD8+ ratios than controls. This is usually interpreted as a therapy-induced immunodeficiency. Our data re-examine the effect of therapy on peripheral blood mononuclear cell immunophenotypic subpopulations in all congenital clotting disorders. Since late 1985 we have prospectively observed HIV-1 uninfected persons with all types and severity of disorder. Controls were household members without clotting disorders or HIV-1 infection. Analyses of immunophenotype and treatment included a longitudinal random effects model. Compared with controls, age-adjusted CD4+ counts were significantly lower in treated patients (P < .0001) and in patients with all types of clotting disorders who were seldom or never treated (P = .0005). Significantly lower values among both treated and untreated clotting disorder subjects (P < .05) were likewise found for total lymphocytes, several other T-cell subsets, and the CD4+/CD8+ ratio. For most indexes, including the CD4+ count and CD4+/CD8+ ratio, the type of clotting deficiency was not a significant variable. Comparing persons who had no or minimal therapy with those having the most showed increases in CD8+ (P = .0017) and CD20+ CD21- counts (P = .0255), and a lower CD20+ CD21+/CD20+ ratio (P = .0106) in the latter. Controls and persons with clotting disorders differ in CD4+ count. Among those with clotting factor disorders, there is no difference attributable to type of clotting disorder or factor therapy. Large amounts of treatment increased CD8+ and CD20+ CD21- counts, but were not associated with a change in CD4+ count.
Autologous and allogeneic bone marrow transplantation for poor prognosis patients with B-cell chronic lymphocytic leukemia
Authors: Rabinowe SN , Soiffer RJ , Gribben JG , Daley H , Freedman AS , Daley J , Pesek K , Neuberg D , Pinkus G , Leavitt PR 
Published: October 2019

Abstract
Twenty patients with poor prognosis B-cell chronic lymphocytic leukemia (B-CLL) underwent uniform high-dose chemoradiotherapy followed by rescue with multiple monoclonal antibody-purged autologous bone marrow (BM) (12 patients) or T-cell-depleted allogeneic BM from HLA-identical siblings (8 patients) in a pilot study to assess the feasibility of BM transplantation (BMT) in this disease. All had poor prognosis disease by either staging, BM pattern, tumor doubling time criteria, or cytogenetics. All patients achieved remission criteria (defined as < or = 2 adenopathy, absence of splenomegaly, < or = 20% of the intertrabecular space involved on BM biopsy) before BMT. Despite the use of fludarabine, a median of three treatment regimens were required to achieve BMT eligibility. After BMT, all patients achieved complete hematologic engraftment. Toxicities were not significantly different between autologous versus allogeneic BMT. Two toxic deaths were observed. Of 19 evaluable patients, 17 clinical complete clinical remissions (89%) were observed, with 2 patients (1 allogeneic and 1 autologous) exhibiting persistent BM disease. Complete clinical remissions were documented at the phenotypic and molecular level for the majority of patients in whom dual fluorescence for CD5 and CD20 (15 of 15; 100%) and Ig gene rearrangements (11 of 14; 79%) were performed. Although long-term follow-up is needed to assess any potential impact on the disease-free and overall survival of these patients, this study shows the feasibility of using high-dose chemoradiotherapy and BMT in patients with poor prognosis B-CLL.
Antibody response in patients with Gaucher disease after repeated infusion with macrophage-targeted glucocerebrosidase
Authors: Richards SM , Olson TA , McPherson JM 
Published: October 2019

Abstract
Recent clinical data have shown that enzyme replacement therapy with macrophage-targeted glucocerebrosidase (GCR) can be effective in treating type 1 Gaucher disease. Sera from 262 patients, repeatedly infused with GCR, were assessed for the presence of antibodies to this therapeutic protein. Patient serum samples obtained at 3-month intervals were assessed by enzyme-linked immunosorbent assay and those with values greater than two standard deviations above the mean value obtained with a pool of normal human sera were further characterized by radioimmunoprecipitation. At the time of these analyses, the duration of patient treatment varied from 3 months to approximately 3 years. Of the 262 patients analyzed, 34 (12.9%) showed IgG antibodies, as confirmed by radioimmunoprecipitation. All patients who seroconverted did so within 1 year of treatment. The predominant antibody developed was the IgG1 subclass. Fourteen patients in the study experienced periodic symptoms suggestive of immediate hypersensitivity. Nine of these 14 patients had antibody to GCR as determined by radioimmunoprecipitation, whereas 5 patients were antibody negative. There was no evidence of the development of IgE antibodies in these 14 patients. The presence of GCR antibodies did not appear to effect efficacy of therapy in any of the patients treated to date.
Occurrence of resistance to retinoic acid in the acute promyelocytic leukemia cell line NB4 is associated with altered expression of the pml/RAR alpha protein
Authors: Dermime S , Grignani F , Clerici M , Nervi C , Sozzi G , Talamo GP , Marchesi E , Formelli F , Parmiani G , Pelicci PG , Gambacorti-Passerini C 
Published: October 2019

Abstract
The mechanism(s) by which acute promyelocytic leukemia (APL) cells acquire resistance to all-trans retinoic acid (ATRA) is poorly understood. We describe here an APL cell line, named NB4.306, that shows resistance to the anti-proliferative action of ATRA. This cell line is also operationally resistant to most ATRA-induced phenotypic modifications (CD11b, CD11c, CD13, and CD33). No significant differences in ATRA intracellular accumulation, efflux, or metabolism were found between NB4.306 and the parent NB4 cell line that could explain the observed resistance of the NB4.306 line. The NB4.306 cell line was found to be positive for the t15;17 translocation and showed the usual pml/RAR alpha fusion bands in both Southern and Northern blot assays, but expressed no detectable amount of the usual pml/RAR alpha protein, as assayed by Western blot analysis using an anti-RAR alpha antibody. These results were confirmed in 14 of 14 clones obtained from the NB4.306 cell line, while 30 of 30 clones obtained from the parental NB4 line expressed the usual 110-Kd fusion polypeptide. It is concluded that the occurrence of resistance to ATRA in the NB4.306 cell line is closely associated to the loss of expression of the intact pml/RAR alpha protein.