bluuebunny/crossref_metadata_2025_split huggingface dataset:
Different regulatory elements are required for response of hepcidin to interleukin‐6 and bone morphogenetic proteins 4 and 9
Authors: Truksa Jaroslav , Peng Hongfan , Lee Pauline , Beutler Ernest 
Published: September 2007

SummaryHepcidin is a major regulator of iron homeostasis. Hepcidin expression is upregulated by inflammatory cytokines, particularly interleukin (IL)‐6 and even more potently by the bone morphogenetic proteins 2, 4 and 9 (BMP‐2, BMP‐4 and BMP‐9). This study showed that the regulation of hepcidin expression by IL‐6 and BMPs occurs through distinct regulatory elements. The induction of hepcidin by BMPs requires at least two regions of the Hamp1 promoter, one between 140–260 bp and the other between 1·6–2·0 kb upstream of the start of translation. Reporter constructs including 1·6–2·0 kb of the Hamp1 promoter were induced >16‐fold by BMPs whereas a 260 bp reporter Hamp1 promoter construct was induced only two‐ to threefold. The distal 1·6–2·0 kb region appeared to contain several different BMP‐responsive elements, as incremental lengthening of the promoter construct in this region produced gradual escalation of BMP‐responsiveness. In contrast, the IL‐6 response required only the proximal 260 bp Hamp1 promoter region. Furthermore, there were no regulatory elements located in the non‐coding or coding regions of Hamp1 and activation of the Hamp1 promoter was absent or markedly reduced in cells of non‐hepatic origin.
Thrombin generation: a comparison of assays using platelet‐poor and ‐rich plasma and whole blood samples from healthy controls and patients with a history of venous thromboembolism
Authors: Tappenden Kerry A. , Gallimore Michael J. , Evans Gillian , Mackie Ian J. , Jones David W. 
Published: September 2007

SummaryWe have developed a whole blood thrombin generation (TG) assay whereby TG is initiated with a low‐tissue factor concentration and monitored using a fluorogenic thrombin substrate. Significantly higher values were found in blood samples from 50 patients with a history of venous thromboembolism (VTE) compared with 31 healthy controls (HC), for peak height (P = 0·0034) and endogenous thrombin potential (ETP) (P = 0·0027). Results from 31 VTE patients and the 31 controls in the absence of corn trypsin inhibitor (CTI) showed significantly higher values in the VTE group for peak height (P = 0·0013) and ETP (P = 0·002). In the presence of CTI, significantly higher values were only seen in ETP (P = 0·024). No significant increases in TG were found using platelet poor (PPP) or ‐rich (PRP) plasma with or without CTI. The whole blood TG assay in the absence or presence of CTI showed a higher proportion (25/50 and 12/31, respectively) of raised peak height and/or ETP values than plasma assays (PPP 9/50 and 5/31 respectively and PRP 13/50 and 6/31, respectively). Our results show the whole blood TG assay is more sensitive for determining the increases in TG in patients with a history of VTE than PPP and PRP TG assays.
β‐Thalassaemia and sickle cell anaemia as paradigms of hypercoagulability
Authors: Ataga Kenneth I. , Cappellini Maria D. , Rachmilewitz Eliezer A. 
Published: September 2007

SummaryThalassaemia and sickle cell disease (SCD) represent the most common forms of hereditary haemolytic anaemia and result from a partial or complete lack of synthesis of one of the major α‐ or β‐globin chains of haemoglobin A or from a single amino acid mutation (β6Glu→Val) of the β‐globin chain respectively. Although they have different pathophysiologies, patients with these conditions manifest both biochemical and clinical evidence of hypercoagulability. While the frequency of various thrombotic complications may vary in β‐thalassaemia and homozygous SCD [sickle cell anaemia (SCA)], patients with both diseases manifest decreased levels of natural anticoagulant proteins, as well as increased markers of thrombin generation and platelet activation. The abnormal phospholipid membrane assymetry present in the red blood cells of β‐thalassaemia and SCA patients, with resultant phosphatidylserine exposure appears to play a significant role in the aetiology of the observed hypercoagulable state. This review presents the available data on the aetiology and clinical manifestations of the coagulation and platelet activation that exist in both β‐thalassaemia and SCA, as well as the potential therapeutic implications resulting from this hypercoagulability.
WASP localizes to the membrane skeleton of platelets
Authors: Lutskiy Maxim I. , Shcherbina Anna , Bachli Eric T. , Cooley Jessica , Remold‐O'Donnell Eileen 
Published: September 2007

SummaryPatients with Wiskott‐Aldrich syndrome (WAS), an X‐linked blood cell disease, suffer from severe thrombocytopenia due to accelerated loss of defective platelets. The affected gene encodes WASP, an actin regulatory protein thought to reside in the cytoplasm of resting leucocytes. In contrast, this study showed that, for platelets, one‐quarter of WASP molecules fractionate in the detergent‐insoluble high speed pellet characterized as the membrane skeleton, the scaffold structure that underlies the lipid bilayer and stabilizes the surface membrane. Following treatment of platelets with thrombin and stirring, which induces cytoarchitectural remodelling, WASP and other membrane skeletal components sedimented at lower g force and partitioned in the low‐speed pellet. Thrombin and stirring also induced WASP tyrosine phosphorylation, a rapid activating reaction, and proteolytic inactivation by cysteine protease calpain. Both the alteration of the sedimentation profile and the proteolytic inactivation were specific for the membrane skeletal pool of WASP and were abrogated in αIIbβ3 integrin‐deficient platelets and in normal platelets treated with an integrin antagonist. The findings demonstrate that WASP is a component of the resting platelet membrane skeleton and participates in membrane skeletal rearrangements downstream of integrin outside‐in signalling. The possible implications for the platelet defect in WAS are discussed.
Low‐dose oral fludarabine plus cyclophosphamide as first‐line treatment in elderly patients with indolent non‐Hodgkin lymphoma
Authors: Fabbri Alberto , Lenoci Mariapia , Gozzetti Alessandro , Chitarrelli Ida , Olcese Francesca , Raspadori Donatella , Gobbi Marco , Lauria Francesco 
Published: September 2007

SummaryTwenty‐five elderly patients with untreated indolent non‐Hodgkin lymphoma were treated with oral fludarabine 25 mg/m2/d (40 mg total dose) and cyclophosphamide 150 mg/m2/d, both for four consecutive days, repeated every 28 d for four cycles. In all, 21 (84%) patients were responsive: 10 patients achieved complete remission while partial response was obtained in 11. During an observation period of 37 months, there was an overall survival rate of 70% and a median event‐free survival of 20 months. Haematological and extra‐haematological toxicity were mild. This reduced‐dose Flu‐based oral regimen showed good efficacy and was simple to administer on an outpatient basis.
Targeting MEK1/2 blocks osteoclast differentiation, function and cytokine secretion in multiple myeloma
Authors: Breitkreutz Iris , Raab Marc S. , Vallet Sonia , Hideshima Teru , Raje Noopur , Chauhan Dharminder , Munshi Nikhil C. , Richardson Paul G. , Anderson Kenneth C. 
Published: September 2007

SummaryOsteolytic bone disease in multiple myeloma (MM) is associated with upregulation of osteoclast (OCL) activity and constitutive inhibition of osteoblast function. The extracellular signal‐regulated kinase 1/2 (ERK1/2) pathway mediates OCL differentiation and maturation. We hypothesized that inhibition of ERK1/2 could prevent OCL differentiation and downregulate OCL function. It was found that AZD6244, a mitogen‐activated or extracellular signal‐regulated protein kinase (MEK) inhibitor, blocked OCL differentiation and formation in a dose‐dependent manner, evidenced by decreasedαVβ3‐integrin expression and tartrate‐resistant acid phosphatase positive (TRAP+) cells. Functional dentine disc cultures showed inhibition of OCL‐induced bone resorption by AZD6244. Major MM growth and survival factors produced by OCLs including B‐cell activation factor (BAFF) and a proliferation‐inducing ligand (APRIL), as well as macrophage inflammatory protein (MIP‐1α), which mediates OCL differentiation and MM, were also significantly inhibited by AZD6244. In addition to ERK inhibition, NFATc1 (nuclear factor of activated T‐cells, cytoplasmic, calcineurin‐dependent 1) and c‐fos were both downregulated, suggesting that AZD6244 targets a later stage of OCL differentiation. These results indicate that AZD6244 inhibits OCL differentiation, formation and bone resorption, thereby abrogating paracrine MM cell survival in the bone marrow microenvironment. The present study therefore provides a preclinical rationale for the evaluation of AZD6244 as a potential new therapy for patients with MM.
Trepanning or trephines: a history of bone marrow biopsy
Authors: Parapia Liakat A. 
Published: September 2007

SummaryTrepanning of bone is the oldest known procedure carried out by man and yet it is only in the last 100 years that we have made use of the technique to diagnose and treat haematological disorders. These advances have been made possible by improvements in instruments, techniques, anaesthesia, laboratory processing and the expertise of haematologists to report the specimens. With the advent of immunological markers and molecular biology, the need for quality bone marrow specimens, if anything, has increased. It will be many years before the bone marrow aspiration/trephine procedure is relegated to the annals of history.
Chromosome 1p21 deletion is a novel prognostic marker in patients with multiple myeloma
Authors: Chang Hong , Ning Yi , Qi Xiaoying , Yeung Joanna , Xu Wei 
Published: September 2007

SummaryThe combination of fluorescence in situ hybridization with cytoplasmic light chain detection identified chromosome 1p21 deletion in 18 (20%) of 87 patients with multiple myeloma. 1p21 deletion was associated with higher serum calcium level, 13q deletion, and t(4;14). Patients with 1p21 deletions had a significantly shorter progression‐free survival (PFS) (median 10·5 vs. 22·3 months, P = 0·0002) and shorter overall survival (OS) (median 33·9 months vs. not reached, P = 0·002) than those without 1p21 deletions. On multivariate analysis, which included deletions of 13q, TP53, t(4;14) and CKS1B amplification, 1p21 deletion remained as an independent risk factor for PFS (P = 0·01) and OS (P = 0·04).
Antiphospholipid antibody syndrome: the flow cytometric annexin A5 competition assay as a diagnostic tool
Authors: Tomer A. , Bar‐Lev S. , Fleisher S. , Shenkman B. , Friger M. , Abu‐Shakra M. 
Published: September 2007

SummaryThe mechanism underlying hypercoagulability in antiphospholipid antibody syndrome (APS) is uncertain. Here, we present a flow‐cytometric assay (FCA) based on the hypothesis that anti‐platelet‐anionic‐phospholipid autoantibodies (aPL) interfere with the activity of the natural anticoagulant protein annexin A5, thereby accelerating platelet procoagulant activity. This study assessed the clinical utility of the feasible FCA, which demonstrates the competition of the patient's aPL with the binding of annexin A5 to the platelet‐anionic‐phospholipids, in the diagnosis of APS. Sixty‐two (94%) of 66 APS patients, 20 (51%) of 39 patients with systemic lupus erythematosus and two (4%) of 49 healthy individuals were positive by FCA. Compared with the anticardiolipin (aCL) assay, the relative sensitivity was 82% and the specificity 73·3%. However, 19 (25%) aCL‐negative patients were positive by FCA; 12 were positive for lupus‐anticoagulant (LA). Compared with LA assay, the relative sensitivity was 85% and the specificity 72·2%. However, 21 (26%) LA‐negative patients were FCA‐positive, 12 were positive for aCL. The FCA was particularly sensitive for APS patients with arterial (97·0%) and gestational vascular complications (100%) with overall sensitivity of 95% and specificity of 97%. Our findings suggest that the FCA is practical, sensitive and specific for the detection of clinically relevant aPL in the diagnosis of APS.
JAK2‐V617F mutation analysis of granulocytes and platelets from patients with chronic myeloproliferative disorders: advantage of studying platelets
Authors: Toyama Kohtaro , Karasawa Masamitsu , Yamane Arito , Irisawa Hiroyuki , Yokohama Akihiko , Saitoh Takayuki , Handa Hiroshi , Matsushima Takafumi , Sawamura Morio , Miyawaki Shuichi , Murakami Hirokazu , Nojima Yoshihisa , Tsukamoto Norifumi 
Published: September 2007

SummaryThere have been conflicting reports over the JAK2‐V617F mutation status of platelets in chronic myeloproliferative diseases (CMPDs). The aim of this study was to analyse JAK2‐V617F status, not only in granulocytes but also in platelets. The JAK2‐V617F mutation was analysed in both granulocytes and platelets in 115 patients with CMPDs using direct sequencing. JAK2‐V617F was detected in granulocytes from 71 of those patients, all 71 of whom also had platelet JAK2‐V617F expression. The remaining 44 patients showed negative JAK2‐V617F expression on granulocytes, but positive JAK2‐V617F expression was detected on the platelets from nine of the 33 essential thrombocythaemia (ET) patients, one of the eight polycythaemia vera patients, and two of the three primary myelofibrosis patients. When ET patients were divided into three groups according to granulocyte and platelet JAK2‐V617F status (both‐positive, platelets‐only positive and both‐negative), the both‐positive and platelets‐only positive groups shared the clinical features of higher white blood cell count and frequent thrombosis. These results suggest that analysis of platelets is a more sensitive approach for detecting JAK2‐V617F in CMPD patients than analysis of granulocytes. They also suggest that previous reports of the incidence of JAK2‐V617F in CMPD patients, obtained using only analysis of granulocytes, could be underestimations.
FUS expression alters the differentiation response to all‐trans retinoic acid in NB4 and NB4R2 cells
Authors: Walsby Elisabeth J. , Gilkes Amanda F. , Tonks Alex , Darley Richard L. , Mills Kenneth I. 
Published: September 2007

SummaryThe FUS gene is overexpressed in acute myeloid leukaemia (AML) patients and has roles in transcription and mRNA processing. We used ectopic expression of FUS and FUS antisense sequences to assess the effect of modulation of FUS expression in all‐trans retinoic acid (ATRA)‐sensitive (NB4) and insensitive (NB4R2) human acute promyelocytic (APL) cell lines which express the t(15:17) translocation. Growth, viability and differentiation patterns were maintained, but the expression of the FUS antisense construct in both the cell lines altered the response to ATRA: the previously ATRA‐sensitive NB4 cells exhibited resistance; whilst the previously resistant NB4R2 cells showed a differentiation response to treatment.
Pseudo‐exon activation caused by a deep‐intronic mutation in the fibrinogen γ‐chain gene as a novel mechanism for congenital afibrinogenaemia
Authors: Spena Silvia , Asselta Rosanna , Platé Manuela , Castaman Giancarlo , Duga Stefano , Tenchini Maria Luisa 
Published: September 2007

SummaryCongenital afibrinogenaemia, characterized by severe fibrinogen deficiency, is caused by mutations within FGA, FGB or FGG. Conventional sequencing of coding regions and splice signals of these three genes did not reveal any mutation in an afibrinogenaemic proband. After confirming disease co‐segregation with the fibrinogen cluster, full intron sequencing was tackled leading to the identification of a novel transvertion within FGG intron 6 (IVS6−320A→T). Its effect on mRNA processing was evaluated in‐vitro: the in‐frame inclusion of a 75‐bp pseudo‐exon carrying a premature stop was found, representing the first report of pseudo‐exon activation as a mechanism leading to afibrinogenaemia.
Reduced‐intensity conditioning for allogeneic haematopoietic stem cell transplantation in relapsed and refractory Hodgkin lymphoma: impact of alemtuzumab and donor lymphocyte infusions on long‐term outcomes
Authors: Peggs Karl S. , Sureda Anna , Qian Wendi , Caballero Dolores , Hunter Ann , Urbano‐Ispizua Alvaro , Cavet James , Ribera Josep M. , Parker Anne , Canales Miguel , Mahendra Premini , Garcia‐Conde Javier , Milligan Donald , Sanz Guillermo , Thomson Kirsty , Arranz Reyes , Goldstone Anthony H. , Alvarez Ivan , Linch David C. , Sierra Jorge , Mackinnon Stephen ,   On behalf of the UK and Spanish Collaborative Groups
Published: September 2007

SummaryThe introduction of reduced‐intensity conditioning (RIC) has enabled the role of allogeneic transplantation to be re‐evaluated in Hodgkin lymphoma (HL). While T‐cell depletion reduces graft‐versus‐host disease (GvHD), it potentially abrogates graft‐versus‐tumour activity and increases infective complications. We compared the results in 67 sibling donor transplantations following RIC in multiply relapsed patients from two national phase II studies conditioned with fludarabine/melphalan. One used cyclosporine/alemtuzumab (MF‐A, n = 31), the other used cyclosporine/methotrexate (MF, n = 36) as GvHD prophylaxis. There was a small excess of chemorefractory cases in the MF cohort (P = NS). MF‐A resulted in significantly lower incidences of non‐relapse mortality, acute and chronic GvHD, but no significant excess of relapse/progression. Post donor lymphocyte infusion (DLI) disease responses occurred in 8/14 (57%) and 6/11 (55%) patients in the MF‐A and MF groups, respectively. Current progression‐free survival (CPFS) was superior with MF‐A (univariate analysis), with durable responses to DLI contributing to the favourable outcome (43% vs. 25%, P = 0·0356). Disease status at transplantation significantly influenced overall survival (P = 0·0038) and CPFS (P = 0·0014), retaining significance in multivariate analyses, which demonstrated a trend towards improved CPFS with T‐cell depletion (P = 0·0939). These data suggest that alemtuzumab significantly reduced GvHD without resulting in a deleterious impact on survival outcomes following RIC in HL, and that durable responses to DLI may be more common following the inclusion of alemtuzumab in the conditioning protocol.
Genetic alterations determine chemotherapy resistance in childhood T‐ALL: modelling in stage‐specific cell lines and correlation with diagnostic patient samples
Authors: Estes David A. , Lovato Debbie M. , Khawaja Hadya M. , Winter Stuart S. , Larson Richard S. 
Published: September 2007

SummaryAcquired drug resistance eventually leads to treatment failure in T‐cell acute lymphoblastic leukaemia (T‐ALL). Immunophenotypic and cytogenetic heterogeneities within T‐ALL influence susceptibility to cytotoxic therapy, and little is known about the mechanisms of drug resistance at specific stages of T‐cell ontogeny. We developed tolerance to therapeutic concentrations of daunorubicin (DNR) and l‐asparaginase (l‐asp) in Jurkat (CD1a−, sCD3+) and Sup T1 (CD1a+, sCD3−) cell lines, having respective ‘mature’ and ‘cortical’ stages of developmental arrest. DNR resistant cells acquired multidrug resistance: 310‐fold increased resistance to vincristine (VCR) and a 120‐fold increased resistance to prednisolone (PRED). Microarray analysis identified upregulation of asparagine synthetase (ASNS) and argininosuccinate synthase 1 (ASS1) to cell lines with acquired resistance to l‐asp, and in the case of DNR, upregulation of ATP‐binding cassette B1 (ABCB1). Suppression of ABCB1, ASNS and ASS1 by RNA interference revealed their functional relevance to acquired drug resistance. Expression profiling of these genes in 80 T‐ALL patients showed correlation with treatment response. This study expands the pool of available drug resistant cell lines having cortical and mature stages of developmental arrest, introduces three new drug resistant T‐ALL cell lines, and identifies gene interactions leading to l‐asp and DNR resistance.
CD4+ T‐cell responses to Epstein–Barr virus (EBV) latent membrane protein 1 in infectious mononucleosis and EBV‐associated non‐Hodgkin lymphoma: Th1 in active disease but Tr1 in remission
Authors: Marshall Neil A. , Culligan Dominic J. , Johnston Peter W. , Millar Colin , Barker Robert N. , Vickers Mark A. 
Published: September 2007

SummaryPrimary infection with Epstein–Barr virus (EBV) in childhood is usually asymptomatic, whereas infection in adolescence may result in infectious mononucleosis (IM) often followed by a fatigue syndrome. EBV latent membrane protein 1 (LMP1) is expressed in latency and in many EBV‐associated tumours, including non‐Hodgkin lymphoma (NHL). Given the regulatory nature of the CD4+ T‐cell response against LMP1 previously reported in healthy donors, we investigated whether patients with active EBV‐driven disease can nevertheless mount effector [T‐helper cell, type 1 (Th1)] anti‐LMP1 responses. We therefore performed a longitudinal study of the nature of CD4+ T‐cell responses to LMP1 in four patients with IM, and five patients with NHL. In both groups, responses changed with time. During symptomatic infection or active tumour growth, responses were dominated by a Th1 effector phenotype, but switched to a regulatory interleukin‐10 response upon recovery. In addition, the fine specificities of the T cells driving these responses evolved. This study showed the dynamic nature of CD4+ T‐cell responses to LMP1, and demonstrated that, although patients can mount Th1 effector responses, recovery from IM and NHL is associated with regulatory responses.
Risk of thromboembolism in 14 000 individuals with coeliac disease
Authors: Ludvigsson Jonas F. , Welander Adina , Lassila Riitta , Ekbom Anders , Montgomery Scott M. 
Published: September 2007

SummaryThe risk of venous thromboembolism (VTE) was examined in individuals with coeliac disease (CD). The Swedish national inpatient register was used to identify 14 207 individuals with a diagnosis of CD (1964–2003). These individuals were matched for age, sex, calendar year and county with 69 048 reference individuals. Cox regression was used to estimate hazard ratios (HRs) for subsequent thromboembolism in individuals with more than 1 year of follow‐up and no prior VTE. CD was associated with an increased risk of subsequent VTE (HR = 1·86; 95% confidence interval (CI) 1·54–2·24). The risk increase was restricted to individuals with CD diagnosed in adulthood. Risk estimates were not affected by the presence of diabetes mellitus or concomitant surgery. Compared with inpatients as reference individuals, CD individuals remained at increased risk of subsequent VTE (adjusted HR = 1·27; 95% CI = 1·06–1·52). In conclusion, this study found a statistically significantly positive association between CD and VTE. This modest association might be explained by a combination of surveillance bias and chronic inflammation.
Detection of CD4+ T‐cell antibodies in a patient with idiopathic CD4+ T lymphocytopenia and cryptococcal meningitis
Authors: Salit Rachel B. , Hankey Kim G. , Yi Rosemary , Rapoport Aaron P. , Mann Dean L. 
Published: September 2007

SummaryIdiopathic CD4+ T lymphocytopenia (ICL) is defined as a CD4+ T‐cell count <0·3 × 109/l or <20% of the total T‐cell count on two occasions in the absence of any immunodeficiency disorder or therapy associated with reduced CD4+ T‐cell count. Although several mechanisms of ICL have been reported, the pathophysiology is still largely unknown. This case report describes a patient who presented with cryptococcal meningitis and was subsequently discovered to meet the criteria for ICL. Flow cytometric analysis of the patient's peripheral blood mononuclear cells revealed antibodies coating a much larger proportion of his CD4+ T cells (33·61%) than the CD4+ T cells of normal donors (3·94 ± 1·77%). The reasons behind the development of these autoantibodies are explored.