bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytokine mRNA expression of bone marrow stromal cells from patients with aplastic anaemia and myelodysplastic syndrome
Authors: Hirayama Yasuo , Kohgo Yutaka , Matsunaga Takuya , Ohi Shigeo , Sakamaki Sumio , Niitsu Yoshiro 
Published: March 2008

Summary We studied mRNA expression of the cytokine granulocyte‐colony stimulating factor (G‐CSF), interleukin‐1β (IL‐1β), IL‐6, IL‐8 and stem cell factor of stromal cells derived from bone marrows of nine normal volunteers, eight patients with aplastic anaemia (AA) and seven patients with myelodysplastic syndrome (MDS). The proportion of endothelial cells. macrophages. fibroblast‐like cells and adipocytes in stromal cells showed no differences between normal volunteers and the patients. Levels of cytokine inKNA expression were determined by reverse transcription‐polymerase chain reaction. Spontaneous expression occurred and this was augmented by IPS stimulation in cells of all the normal volunteers and in most patients.When stimulated by LPS. the mean G‐CSF and IL‐1β mRNA expressions in patients with AA were significantly higher than normal volunteers. but there was one patient showing lower IL‐1β. IL‐6 and 71,‐8 expression with no response to LPS. LPS‐induced IL‐6 and IL‐8 expression of two patients with MDS were significantly higher than normal.The spontaneous and LPS‐induced protein concentration of G‐CSF, IL‐6 and IL‐8 in culture supernatants from 15, 10 and four patients, correlated well with the niKNA expression. The correlation coefficients were 0.92. 0.78 and 0.91. respectively.In conclusion, there were a few patients whose aetiology appeared to be reduction of stromal cytokine expression in AA. but most patients with AA and MDS expressed normal or high levels of cytokine mKNA.
The effects of saline solutions on red cell shape: a scanning‐electron‐microscope‐based study
Authors: Simpson L. O. 
Published: March 2008

Summary Red cells appear to change shape in response to alterations in their environment both in vitro and in viva To investigate the qualitative aspects of this phenomenon, five drops of a venous blood sample were fixed in buffered glutaraldehyde for baseline observations and 0.5 ml of blood added to 4 ml of four different saline solutions. Triplicated 10 drop samples from the suspensions were fixed in the glutaraldehyde solution after 2.5, 5, 10, 20 and 40 min and prepared for scanning electron microscopy.Red cell shape analysis of the resulting micrographs showed that the cells had changed shape, although no two patterns of change were the same.
Clinical, haematological and cytogenetic features in 24 patients with structural rearrangements of the Q arm of chromosome 3
Authors: Grigg A. P. , Gascoyne R. D. , Phillips G. L. , Horsman D. E. 
Published: March 2008

Summary To determine the frequency and clinical significance of acquired abnormalities of chromosome 3 at q21 and q25–26 in haematological malignancy, we reviewed the haematological and cytogenetic features of 24 patients with a 3q rearrangement identified amongst 1200 cases with clonal cytogenetic abnormalities detected at our institutions during a 12‐year period. Thirteen patients presented with de novo acute myeloid leukaemia (AML), 10 with myelodysplasia (MDS) and one in blast phase of chronic myelogenous leukaemia. Twenty patients (83%) had megakaryocytic dysplasia and 14 (58%) had normal or increased numbers of megakaryocyte, but only four patients (16%) had absolute thrombocytosis > 500 × 109/l (three with AML, one with MDS transforming to AML).A review of 205 cases of AML investigated in our institutions between 1985 and 1990 for whom cytogenetic results were obtained revealed that a platelet count > 500 × 109/l at presentation was highly suggestive of an underlying 3q abnormality. A limited review of the literature on this subject confirmed that 15‐20% of patients with a 3q abnormality will have thrombocytosis. The response of these patients to conventional antileukaemic therapy is uniformly poor, despite haematological and clinical differences between the subtypes of 3q rearrangements.
Acute hepatitis C infection in patients undergoing therapy for haematological malignancies: a clinical and virological study
Authors: Brink N. S. , Chopra R. , Perrons C. J. , Ring C. J. A. , Garson J. A. , Briggs E. M. , Goldstone A. H. , Linch D. C. , Tedder R. S. 
Published: March 2008

Summary. Patients receiving multiple transfusions are at risk of acquiring hepatitis C (HCV) infection from a donor population which is unscreened for hepatitis C antibodies (anti‐HCV). Prior to the introduction of blood donor screening for anti‐HCV in the U.K., a group of patients undergoing therapy for haematological malignancies, with repeatedly abnormal liver function tests, were investigated for acute HCV infection. Thirty‐two patients had repeatedly raised serum transaminases, and eight of these (25%) had evidence of an acute HCV infection. The diagnosis was made by the detection of HCV‐RNA in the patients' serum using a complementary DNA/polymerase chain reaction (cDNA/PCR) procedure. All eight patients had received myeloablative chemotherapy and three had undergone bone marrow transplantation.HCV infection contributed significantly to the morbidity of this group of patients in the short term whilst they were undergoing treatment for their underlying haematological condition. The long‐term effects have yet to be evaluated. In an attempt to decrease hepatic damage due to HCV. three patients were placed on interferon therapy. None showed a sustained reduction in serum transaminases or HCV viraemia. It is hoped that the introduction of anti‐HCV screening of blood donors, will reduce the frequency of transfusion‐acquired HCV infections. Early observations suggest that this is the case, as we have seen no new cases of HCV infection in our unit since the introduction of donor screening in September 1991.
UVB radiation exposes fibrinogen binding sites on platelets by activating protein kinase C via reactive oxygen species
Authors: van Marwijk Kooy M. , Akkerman J. W. N. , Asbeck S. van , Borghuis Lizette , van Prooijen H. C. 
Published: March 2008

Previous studies have shown that ultraviolet B (UVB) radiation causes platelet aggregation by exposing fibrinogen binding sites via activation of an intracellular mechanism. In the present study we have further investigated the routes of platelet activation following UVB exposure. Evidence is provided that UVB radiation does not activate the platelets via the classical Phospholipase A2 and Phospholipase C routes. Despite this observation, UVB‐induced fibrinogen binding was found to be correlated with a 40% increase in phosphorylated 47 kD protein. Both findings could be completely inhibited in the presence of staurosporine, a potent inhibitor of protein kinase C (PK‐C). In efforts to explain the mechanism of PK‐C activation by UV radiation we found that both UV‐induced PK‐C activation and platelet aggregation were significantly reduced in the presence of specific scavengers for reactive oxygen species including superoxide dismutase and catalase.We conclude that exposure of platelets to UVB radiation can activate PK‐C via oxygen radicals, resulting in exposure of fibrinogen binding sites and subsequent platelet aggregation.
Biological activity of recombinant factor VIII variants lacking the central B‐domain and the heavy‐chain sequence Lys713‐Arg740: discordant in vitro and in vivo activity
Authors: Mertens K. , Donath M. J. S. H. , Leen R. W. van , Keyzer‐Nellen M. J. M. de , Verbeet M. Ph. , Bos J. M. Klaasse , Leyte A. , Mourik J. A. van 
Published: March 2008

Summary. Recombinant factor VIII variants with overlapping deletions spanning the region Lys713‐Ile1668 have been expressed in mammalian cells, and analysed for biological activity both in vitro and in vivo. Two distinct assay systems were used to measure the activity in vitro. The one‐stage coagulation assay served to assess factor VIII procoagulant activity while a spectrophotometric assay was used for the quantification of factor VIII cofactor activity in factor IXa‐dependent factor X activation. Deletion of the entire B‐domain (Ser741‐Arg1648) resulted in a protein with similar procoagulant and cofactor activity. In contrast, factor VIII‐del(713–163 7), which has a deletion that also comprises the heavy‐chain sequence Lys713‐Arg740, had lost factor VIII procoagulant activity while factor VIII cofactor activity was retained. This functional inconsistency was further addressed by comparing purified factor VIII‐del(713–1637) with factor VIII‐del(868–1562). a mutant with normal in vitro activity.Kinetic studies of factor Xa formation revealed that higher concentrations of thrombin were required to develop the cofactor activity from factor VIII‐del(713–1637) than needed for factor VIII‐del(868–1562) or plasma factor VIII. The physiological significance of this finding was assessed in dogs with haemophilia A. Both deletion mutants were similar to plasma factor VIII with regard to binding to von Willebrand factor and half‐life and recovery. Employing the cuticle bleeding time model, factor VIII‐del(868–1562) was found to be indistinguishable from plasma factor VIII, whereas factor VIII‐del(713–1637) was less effective. The increased throm‐bin‐resistance of factor VIII‐del(713–1637) thus limits both procoagulant activity and haemostatic efficacy in cuticle bleeding. These observations suggest that the heavy‐chain sequence Lys713‐Arg740, although dispensable for factor VIII cofactor function per se, is involved in the proteolytic activation of factor VIII both in vitro and in vivo.
The correction of coagulometer effects on international normalized ratios: a multicentre evaluation
Authors: Poller L. , Thomson J. M. , Taberner D. A. , Clarke D. K. 
Published: March 2008

One hundred and twenty‐nine centres in the U.K. participated in a study to test the reliability of the three methods of correction for coagulometer effects on international normalized ratios (INR). Results from 37 centres which tested three warfarinized plasmas by the manual method were taken as the ‘true’INR for the assessment of coagulometers. 63 centres (11 manual and 52 using coagulometers) determined their local International Sensitivity Index (ISI) in a calibration exercise. This was performed with a set of 20 lyophilized plasma calibrants with certified manual prothrombin times for the thromboplastin used in the study.The following methods of INR derivation were compared by assessing the percentage deviation from the three INR values established by 37 manual users:I. No coagulometer correction, i.e. (local PT/reference manual normal pT)manual ISI.II. Coagulometer ratio correction, i.e. (local coagulometer PT/local coagulometer MNPT)manual ISI.III. Local system ISI, i.e. (local coagulometer PT/local coagulometer MNPT)local system ISI.IV. System ISI, i.e. (local coagulometer PT/local coagulometer MNPT)system ISI.The local system ISI with the plasma calibrants (method III) gave the most reliable correction (mean deviation from ‘true’INR 4·87%). The method which gave the least was with the coagulometer ratio correction, i.e. the manual ISI and local coagulometer MNPT (mean 11·25%). The system ISI tested with ACL coagulometers gave less correction than the local ISI calibration.The local system calibration with lyophilized plasmas also avoids some of the constraints on conventional thromboplastin calibrations.
Two cases of congenital dyserythropoietic anaemia type I associated with unusual skeletal abnormalities of the limbs
Authors: Brichard B. , Vermylen C. , Scheiff J. M. , Michaux J. L. , Ninane J. , Cornu G. 
Published: March 2008

This report describes the cases of two young female patients with congenital dyserythropoietic anaemia (CDA) type I who presented similar hand and foot skeletal abnormalities: lack of distal phalanges and nails, and syndactyly. Up to now, some morphological malformations have been described in association with CDA type I but there is no report of skeletal defects.These two cases are suggestive of a possible association between this hereditary anaemia and specific skeletal abnormalities of the distal extremities.
Differential regulation of M‐CSF and IL‐6 gene expression in monocytic cells
Authors: de Wit Harry , Esselink Mariet T. , Halie M. Ruud , Vellenga Edo 
Published: March 2008

Summary Using the human monocytic cell line Mono Mac 6 we studied the involvement of Ca2+, protein kinase A (PKA), and protein kinase C (PKC) dependent pathways in the regulation of M‐CSF and IL‐6 gene expression. The results demonstrate that on activation with the calcium ionophore A23187 both M‐CSF and IL‐6 mRNA are induced after 3 and 6 h respectively. Co‐stimulation with A23187 plus PMA resulted in an up‐regulation of M‐CSF mRNA and a downregulation of IL‐6 mRNA. Conversely co‐stimulation with A23187 plus DBcAMP resulted in a down‐regulation of M‐CSF mRNA and an up‐regulation of IL‐6 mRNA.Nuclear run‐on and mRNA half‐life studies showed that the effects on the M‐CSF expression were related to changes at transcriptional and post‐transcriptional level. In contrast, the effects on the IL‐6 gene expression seems to be mediated at post‐transcriptional level. With regard to the secretion of the IL‐6 protein it was shown that it closely follows the accumulation of IL‐6 mRNA. Taken together, the data show that several intracellular signalling pathways control strictly the cytokine expression in monocytic cells which gives the cells the opportunity to respond variably to external activation signals.
Domiciliary desensitization therapy for young boys with haemophilia and factor VIII inhibitors
Authors: Lilleyman J. S. 
Published: March 2008

Summary Immune tolerance was induced in five consecutive young boys with haemophilia and factor VIII inhibitors using frequent conventional doses of human factor VIII.All therapy was given at home by parents and the four youngest boys had surgically implanted central venous catheters (Port‐a‐Cath). Two catheters eventually became infected after 2 and 4 years respectively, otherwise the devices were trouble‐free and liked by the families concerned.Regular domiciliary factor VIII therapy in pre‐school children is not difficult with an aid to venous access and immune tolerance can be achieved in those developing factor VIII inhibitors.
The human platelet alloantigens, HPA‐5(a+ b‐) and HPA‐5(a‐ b+), are associated with a Glu505/Lys505 polymorphism of glycoprotein Ia (the α2 subunit of VLA‐2)
Authors: Simsek S. , Gallardo D. , Ribera A. , von dem Borne A. E. G. Kr. 
Published: March 2008

Summary. GP Ia/IIa (also called VLA‐2 or α2β1) is the primary receptor for collagen on platelets. The human platelet alloantigens HPA‐5a(Brb) and HPA‐5b(Bra) have been found to reside on the platelet GP Ia/IIa complex. In order to establish the molecular basis of the HPA‐5 system, platelet RNA was isolated from HPA‐5 (a+ b‐) and HPA‐5(a b+) individuals. After reverse transcription, cDNA coding for glycoprotein Ia (GP Ia) was amplified by the polymerase chain reaction (PCR). Nucleotide sequence analysis of the PCR products revealed an A·G polymorphism at base pair 1648 of the coding region of the mature protein, resulting in a substitution of lysine (AAG) in HPA‐5b(Bra) by glutamic acid (GAG) in HPA‐5a (Brb) at amino acid 505. Subsequent PCR‐ASRA (allele‐specific restriction enzyme analysis) with Mnl I using cDNA derived from three HPA‐5 (a+b‐), one HPA‐5 (a+b+) individuals demonstrated that HPA‐5a and −5b alleles are distinguishable by DNA typing.In addition to the A→G substitution at base pair 1648, three silent mutations were identified, G→C (195 bp), C→T (837 bp), G→A (1041 bp).
Inhibition of erythropoietin production in vitro by human interferon gamma
Authors: Vannucchi A. M. , Grossi A. , Rafanelli D. , Statello M. , Cinotti S. , Rossi‐Ferrini P. 
Published: March 2008

SummaryThe effects of interferon‐gamma (IFN‐γ). alone and in combination with IL‐1, IL‐6 and tumour necrosis factor‐alpha (TNF‐α), on in vitro erythropoietin (Epo) production by the human hepatoma Hep 3B cell line were evaluated. The addition of IFN‐γ to either unstimulated or cobalt chloride (CoCl2)‐treated Hep 3B cells resulted in a dosedependent inhibition of Epo release in the medium by as much as 70% at 1000 U/ml. Half‐maximal inhibition was observed at around 50 U/ml. According to previous observations, IL‐6 had a stimulatory effect on Epo production by CoCl2‐treated Hep3B cells: however, the simultaneous addition of IFN‐γ and IL‐6 resulted in a reversal of the stimulatory effects due to IL‐6. IFN‐γ and IL‐1 had an additive inhibitory effect, whereas IFN‐γ and TNF‐α acted in a synergistic fashion in inhibiting Epo production by Hep 3B cells. The inhibitory effect of IFN‐γ appeared to be due to a down‐modulation of Epo mRNA levels in CoCl2,‐treated Hep 3B cells, as shown by Northern blot analysis.These data indicate that Epo production by hepatoma cells in vitro is inhibited by IFN‐γ, and that a complex network of interacting cytokines may regulate Epo production in response to an hypoxic stimulus. Overall, these results also suggest that IFN‐γ might have a role in the defective Epo production observed in several inflammatory and immunemediated disorders characterized by relatively high IFN‐γ plasma levels.
Mercury compounds induce a rapid increase in procoagulant activity of monocyte‐like U937 cells
Authors: Kaneko Hiroshi , Kakkar Vijay V. , Scully Michael F. 
Published: March 2008

Summary. When monocytic leukaemia line U937 cells were incubated in the presence of HgCl2there was a rapid increase in tissue factor (TF)‐dependent procoagulant activity, reaching a maximum (equivalent to the total TF activity observed when cells had been subjected to a freeze/thaw cycle) after 15 min at 50 μmHgCl2and after 30 min at 10 μmHgCl2. Two other heavy metal compounds, AgNO3and phenylmercuric acetate, caused a similar increase in TF activity. The increase was independent of protein synthesis. Other reagents tested, CdCl2, ZnCl2, NiCl2, ADP, FMLP and monocyte chemotactic factor (MCF‐1), did not cause a rapid increase in functional activity, when tested under the same experimental conditions. The addition of HgCl2to the cells causes, in a concentration‐dependent manner, a 10‐12‐fold increase in intracellular calcium (Cai) which coinicides with increase in TF activity. Calcium ionophore also caused an increase in TF activity of the U937 cells. Upon treatment with HgCl2the cells surface of U937 cells showed a large increase in the level of phosphatidylserine (PS) on the cell surface (as measured by potentiation of the rate of activation of prothrombin by factor Xa‐factor Va) but with no change in the level of TF antigen on the cell surface. We consider that the TF is present on the cell surface of the monocyte but relatively inactive towards the physiological substrate, factor X (FX), until HgCl2causes a change in the polarity of the cell membrane exposing PS on the outer leaflet by a mechanism likely to be enhanced by the increase in intracellular calcium.
Activation of the coagulation cascade in severe falciparum malaria through the intrinsic pathway
Authors: Clemens R. , Pramoolsinsap C. , Lorenz R. , Pukrittayakamee S. , Bock H. L. , White N. J. 
Published: March 2008

Summary. The mechanisms involved in the activation of the coagulation cascade in severe falciparum malaria were studied in 22 adult patients (19 male, three female) aged 18‐45 (mean ± SD 31 ± 11) years. Of these, nine had multiple vital organ dysfunction, and bleeding occurred in four patients, two of whom died. During acute illness the reduction in plasma antithrombin III (AT III) concentrations and elevation in thrombin‐AT III complexes were associated with significant reductions in factor XII and prekallikrein activities, and an increase in the C1 inhibitor antigen/activity ratio. Serial plasminogen activity remained within the normal range in all patients while protein C activity was significantly reduced. All patients had markedly elevated plasma polymorphonuclear leucocyte elastase (PMN‐elastase) levels with mild depletion of alpha‐2 macroglobulin but normal concentrations of alpha‐1 antitrypsin. There was no correlation between PMN‐elastase concentrations and any of the coagulation parameters or concentrations of proteinase inhibitors. These results suggest that the intrinsic pathway of the clotting cascade is activated in severe malaria. This may cause activation of the complement system and release of bradykinin and PMN‐elastase and could contribute to the pathogenesis of severe malaria.
Ultrastructural localization of the small GTP‐binding protein Rap 1 in human platelets and megakaryocytes
Authors: Berger Gaëtan , Quarck Rozenn , Tenza Danié;le , Levy‐Toledano Sylviane , Gunzburg Jean de , Cramer Elisabeth Martin 
Published: March 2008

Summary. Several functions have been proposed for Rap 1B in human platelets, including the regulation of phospholipase (PL) Cγ and Ca2+ ATPase. However, its localization is largely unknown. In the present study we have investigated the subcellular distribution of Rap1 by immunocytochemical techniques using affinity purified polyclonal antibodies raised against residues 121–137 common to the 95% homologous Rap1A and Rap1B proteins. By immuno‐fluorescence, a positive labelling was obtained on intact resting platelets and was abolished after adsorption of the antibodies with the control peptide. Immunoelectron microscopy was then used to further define the subcellular localization of Rap1B in platelets and megakaryocytes (MK). In resting cells, immunolabelling for Rap1B was associated with the plasma membrane, mostly at its inner face, and lined the membrane of the open canalicular system (OCS). Some labelling was also found outlining the α‐granules, identified as such by a double labelling with an anti‐GPIIb‐IIIa. On thrombasthenic platelets the same localization was observed. When platelets were stimulated by thrombin, immunolabelling for Rap1B was redistributed to the zones of fusion of the granules with the OCS, and to the plasma membrane with a higher concentration on pseudopods. Human MK expressed Rap1 and the staining revealed the association of the protein with the demarcation membranes and α‐granules.This study presents a first approach to the localization of a small GTP binding‐protein Rap1B in whole platelets and MK, and shows its association with both the plasma and OCS membranes, as well as with the α‐granule membranes.
Chronic granulocytic leukaemia presenting with an extramedullary T lymphoblastic crisis
Authors: Jacob A. , Rowlands D. C. , Patton N. , Holmes J. A. 
Published: March 2008

Summary. A 33‐year‐old man presented with hepatosplenomegaly and lymphadenopathy. bone marow findings were consistent with Philadelphia‐positive acceleratedphase chronic granulocytic leukaemia (CGL). Lymph node histology and immunhistochemistry were diagnostic of T lymphoblastic lymphoma. Molecular studies on lymph node DNA identified rearrangement within the major breakpoint cluster region (M‐ber), indicating a common clonal origin of CGL and the T lymphoblastic lymphoma.We report the second case where extramedullary T lymphoblastic crisis was the presenting feature of CGL.