bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of circulating erythroid colony‐forming cells in normal and polycythaemic man
Authors: Mladenovic J. , Adamson J. W.
Published: March 2008

Summary.

Circulating erythroid progenitors from 10 patients with polycythaemia vera, nine with secondary polycythaemia and 10 normal subjects were studied in culture to determine their frequency, requirements for erythropoietin (ESF) and physical characteristics. Increased numbers of erythroid progenitors were detected in circulation from the patients with polycythaemia vera when compared to patients with secondary polycythaemia or normals, and 19 ± 3% of these progenitors formed endogenous colonies without added ESF. Velocity sedimentation analysis showed that the majority of ESF‐dependent erythroid progenitors in all study groups sedimented at 6.46 mm/h. The circulating endogenous erythroid colony‐forming cells in polycythaemia vera patients sedimented more rapidly. Tritiated thymidine suicide experiments failed to detect significant differences between the percentages of endogenous and ESF‐dependent progenitors in DNA synthesis in polycythaemia patients and normals. Thus, differences in cell cycle state were not responsible for the more rapid sedimentation of endogenous colony‐forming cells. These results further define characteristics of circulating erythroid progenitors in polycythaemia vera and normal subjects and suggest that simple culture of peripheral blood cells may be useful in the differential diagnosis of polycythaemia.
Azure B‐eosin Y stain as the standard Romanowsky‐Giemsa stain*
Authors: Wittekind D. H. , Kretschmer Vera , Sohmer Inge
Published: March 2008

Summary.

An azure B‐eosin Y stain is described which is intended to fulfil the requirements of a standard Romanowsky‐Giemsa stain. It consists of pure azure B and eosin Y only and gives strictly reproducible staining results.
Recurrent thrombocytopenia, erythroid hypoplasia and sideroblastic anaemia associated with hypothermia
Authors: O'Brien H. , Amess J. A. L. , Mollin D. L.
Published: March 2008

Summary.

A distinct and previously undescribed haematological picture was noted in three patients with hypothermia. During hypothermia there was anaemia with reduced normoblastic erythropoiesis, marked sideroblastic change and thrombocytopenia in the presence of a normal number of megakaryocytes. In two patients as the body temperature returned to normal these changes were slowly reversed. Evidence both from observations in patients and from animal experiments is given why the haematological changes are due to the hypothermia.
Stroma free human platelet lysates potentiate the in vivo thrombogenicity of factor Xa by the provision of coagulant‐active phospholipid
Authors: Giles Alan R. , Nesheim Michael E. , Hoogendoorn Hugh , Tracy Paula B. , Mann Kenneth G.
Published: March 2008

Summary.

A stroma free platelet lysate supernatant (PLS) was prepared by repeatedly freezing and thawing a human platelet suspension separated from platelet rich plasma by gel filtration. The material was potently thrombogenic in a stasis model in rabbits, but only when combined with a purified preparation of factor Xa. The dose of factor Xa used was not thrombogenic when given alone. Initial evaluation suggested the presence of a factor V activator when PLS shortened the clotting time of normal but not a V deficient plasma. Subsequent evaluation, in a system employing purified components of the prothrombinase complex and a marker of thrombin generation, dansyl‐arginine‐N‐(3‐ethyl‐1,5‐pentanediyl)amide (DAPA), failed to confirm the presence of a factor V activator. Further evaluation in this system demonstrated that the procoagulant activity related to the content of coagulant‐active phospholipid. Thin layer chromatography confirmed the presence of phospholipids known to have coagulant activity. These components were isolated by a lipid extraction procedure and the phospholipid replacing activity in the in vitro assay with DAPA was quantitatively retained. The extracted material was non‐thrombogenic in vivo but augmented the thrombogenicity of a purified preparation of Xa.
Results of immunosuppression in 170 cases of severe aplastic anaemia
Authors: Gluckman E. , Devergie A. , Poros A. , Degoulet P.
Published: March 2008

Summary.

This is a report of the European Group of Bone Marrow Transplant (EGBMT) on the influence of immunosuppression (IS) on survival of patients with severe aplastic anaemia (SAA). Fourteen teams participated in this survey involving 170 cases treated from 1974 to December 1980. The 1 year survival was 62.7%. Three types of treatment were used: (1) anti‐thymocyte globulin (ATG) alone, (2) anti‐thymocyte globulin and haplo‐identical related bone marrow infusion, and (3) high dose bolus‐6‐methyl‐prednisolone (b‐6 MePr). There was no statistical difference in survival between these three groups. Androgens did not modify survival. Blood counts before treatment had a significant prognostic value. Patients with less than 0.2 x 109/l granulocytes and less than 10 x 109/l reticulocytes had 40% 1 year survival; the others had more than 70% 1 year survival. Patients with complete or partial reconstitution had the same good prognosis. In contrast, patients with no improvement after IS had a 27% 1 year survival. Several successive courses of IS improved the prognosis of non‐responding patients. This survey confirms that IS improves the survival of patients with SAA. A prospective study will be performed to define the best and safest form of IS and to correlate clinical results with in vitro tests.
The Wiskott‐Aldrich syndrome: studies on a possible defect in mitochondrial ATP resynthesis in platelets
Authors: Akkerman J. W. N. , van Brederode W. , Gorier G. , Zegers B. J. M. , Kuis W.
Published: March 2008

Summary.

A possible defect in mitochondrial ATP resynthesis in platelets has been used for detection of Wiskott‐Aldrich syndrome carriers (Shapiro et al, 1978). The detection was based on an abnormal adrenaline‐induced platelet aggregation under conditions that only the mitochondria provide metabolic energy. We evaluated the test and found false negative and false positive results which raised doubts about the applicability of the test and the nature of the underlying defect. Direct analysis of mitochondrial ATP regeneration in patients and carriers showed an impaired mitochondrial energy production which was insufficient to maintain ATP homeostasis when glycolytic energy production was inhibited. Also abnormal was the fall in metabolic ATP concentration during stimulation with adrenaline and especially with thrombin when the platelets were incubated in glucose‐free medium. These data provide direct evidence for a regulation defect in mitochondrial ATP resynthesis in platelets of patients and carriers with Wiskott‐Aldrich syndrome.
The morphology and cytochemistry of human T‐cell subpopulations defined by monoclonal antibodies and Fc receptors
Authors: Armitage R. J. , Linch D. C. , Worman C. P. , Cawley J. C.
Published: March 2008

Summary.

Leu 2a+ (suppressor/cytotoxic) and Leu 3a+ (helper/inducer) T‐cell subsets of normal peripheral blood lymphocytes, purified by fluorescence‐activated cell sorting, respectively showed 50 ± 22% (range 31‐92%) and 82 ± 9% (range 69‐93%) dot non‐specific esterase (NSE) and 48 ± 20% (range 31‐91%) and 79 ± 10% (range 64‐92%) dot acid‐phosphatase (APase) staining. Mature T cells defined by monoclonal antibody (UCHT1) displayed 81% and 79% dot NSE and APase positivity, while E‐rosetting cells not staining with UCHT1 showed only 15% and 10% dot‐positivity and were generally larger cells with more abundant cytoplasm. Examination of Fc‐rosetting cells within the different T‐cell subsets showed that dot positivity was not directly related to μFc receptor (μFcR) expression; particularly among Leu 2a+ lymphocytes, many μFcR+ cells lacked dot staining.

It is concluded that dot staining for hydrolytic enzymes is a marker of true T‐cells (as defined by monoclonal antibodies), although a minority of such cells (±20%) lack this staining pattern. Although Leu 3a+ cells display a higher percentage of dot positivity than do Leu 2a+ cells, the difference is not clinically useful, and the two cell populations are not readily distinguishable on morphological grounds.

The previously reported association between dot staining and μFc receptor expression is shown to be an indirect one, attributable to the fact that most T‐cells, defined by monoclonal antisera, possess μFcR whereas most E+ UCHT1− cells lack μFcR.
The effects of deoxycoformycin and deoxyadenosine on deoxyribonucleotide concentrations in leukaemic cells
Authors: Sylwestrowicz T. , Piga A. , Murphy P. , Ganeshaguru K. , Russell N. H. , Prentice H. G. , Hoffbrand A. V.
Published: March 2008

Summary.

Intracellular deoxynucleoside triphosphate pools of normal bone marrow, thymocytes and cells from patients with ALL and AML were measured after 2 h incubation with deoxycoformycin (dCF) 10−5 M and deoxyadenosine (AdR) 10−4 M in vitro and after another 30 min incubation in the absence of dCF and AdR (‘chase’ experiment). Incubation with dCF and AdR resulted in a significant rise of dATP concentrations in all groups (the highest rises occurring in the leukaemic groups particularly in AML and Thy‐ALL). The concentrations of the other three deoxyribonucleoside triphosphates fell in all groups. The dATP level fell during the‘chase’period but in Thy‐ALL and thymocytes this fall was insignificant and slower than in the other groups. This suggests that not only intracellular build‐up of dATP but also the capacity of the cell to degrade dATP is important for in vivo cytotoxicity of dCF treatment. These results help to explain the differences in response to dCF of the different leukaemias.
Homozygous deletional α+ thalassaemia associated with unequal expression of the two remaining α1 genes (α1A and α1Q)
Authors: Pagnier J. , Elion J. , Lapouméroulie C. , Vigneron C. , Labie D.
Published: March 2008

Summary. A Cambodian family presenting several haemoglobinopathies, Hb E, Hb Q and α+ thalassaemia, has been investigated. DNA analysis showed that the thalassaemia syndrome corresponds to a leftward type (4.2 kb) deletional from of α+ thalassaemia. Genotypes found in the family are: propositus ‐αA/‐αQ, βA/βE, mother and older sister αAαA/ ‐αQ, βA/βE; father αAαA/‐αA, βA/βA. The propositus consistently presents an αQ/αA chain ratio of 60/40 although both chains are products of α1 loci. The relatively higher expression of the αQ chain is not observed in the mother and therefore makes it unlikely to reflect anything other than differential expression of the maternal ‐αQ/ and paternal ‐αA/ haplotypes. This observation raises the possibility that both haplotypes are not strictly identical and that the region of the cross‐over event is important for α gene expression.
Hepatocyte iron kinetics in the rat explored with an iron chelator
Authors: Pippard Martin J. , Johnson David K. , Finch Clement A.
Published: March 2008

Summary. The hepatocyte metabolism of 59Fe‐labelled ferritin, haemoglobin‐haptoglobin and transferrin has been examined in rats. All three forms of 59Fe became transiently available to desferrioxamine (DF) at the time they would otherwise have entered storage or alternative pathways of iron metabolism. However, differences in both the patterns of spontaneous 59Fe reutilization by normal and iron deficient rats and the partition of chelate iron excretion between bile and urine, suggested that iron in transit within hepatocytes did not behave as a single common pool. Ferritin 59Fe, entering a pool of non‐radioactive iron the size of which is determined by liver iron stores, was chelated predominantly into the bile. Transferrin 59Fe was distinguished by a greater reflux to the erythron in iron deficient rats, and by excretion of a larger proportion of 59Fe chelated by DF in the urine. Haemoglobin‐haptoglobin 59Fe followed a metabolic pathway which was relatively independent of both the iron stores and DF. If the heterogeneous behaviour of rat hepatocyte transit iron has a parallel in man, alterations in the size of similar chelatable iron pools could explain the dependence of DF‐induced urine and faecal iron excretion on both liver iron stores and the level of erythropoiesis.
The influence of the ‘collection injury’ on the survival and distribution of Indium‐ 111 ‐labelled canine platelets
Authors: BBADENHORST P. N. , Lötter M. G. , DuP. Heyns A. , Van Reenen O. N , Herbst C. , Pieters H. , Kotze H. F. , Duyvené de Wit L. J. , Minnaar P. C.
Published: March 2008

Summary. The extent of the ‘collection injury’ sustained by platelets during labelling with In‐lll‐oxine was investigated in three matched pairs of beagle dogs. The influence of the procedure on the survival, kinetics, in vivo distribution and fate of the labelled platelets was determined by serial blood sampling and quantitative computerized scintillation camera studies. Injured labelled platelets were removed in the matched dog acting, as a biological filter. The survival, distribution and fate of the ‘filtered’ and ‘unfiltered’ platelets were compared. The mean platelet lifespan of the ‘filtered’ and ‘unfiltered’ platelets did not differ significantly, but the shape of the survival curve of the filtered platelets fitted a linear function more closely than that of the unfiltered platelets. Radioactivity in the different organs and regions was serially quantitated and expressed as a percentage of whole body radioactivity. Splenic and hepatic radioactivity of filtered and unfiltered platelets did not differ significantly at equilibrium or at the end of platelet lifespan. It is concluded that the currently employed isolation and labelling techniques for platelets are suitable for quantitative in vivo studies with a computerized scintillation camera system. The shape of platelet survival curves should, however, be interpreted with some caution as it may be influenced by these procedures.
Response to infusions of polyelectrolyte fractionated human factor VIII concentrate in human haemophilia A and von Willebrand's disease
Authors: Tuddenham E. G. D. , Lane R. S. , Rotblat F. , Johnson A. J. , Snape T. J. , Middleton S. , Kernoff P. B. A.
Published: March 2008

Summary. Factor VIII was purified from cryoprecipitate by ion exchange chromatography on solid phase polyelectrolyte E‐5 (PE‐E5). The product was highly purified (3.5 u VIII: C/mg protein) compared to conventional concentrate (0.3 u VIII: C/mg protein) with low fibrinogen, low isoagglutinin titre, and a ratio of factor VIII coagulant activity (VIII: C) to factor VIII related antigen (VIIIR: Ag) of 16:1.

Trial infusions of this material (PE VIII) were given to three patients with severe haemophilia A and one patient with homozygous von Willebrand's disease. These patients also each received separate infusions of intermediate purity concentrate (IPC) for comparison. There were no adverse effects. The mean half life of VIII: C after PE VIII infusion in the haemophiliacs was 10.9 h and after IPC was 12.1 h, a statistically insignificant difference. The survival of factor VIII coagulant antigen (VIII:CAg) was similar to that of VIII:C. In contrast, the half life of VIII:C and of VIII:CAg was very short after infusion of PE VIII in the patient with von Willebrand's disease (2.4 h). IPC when infused in this patient produced a typical secondary rise of VIII:C. Two bleeding episodes in severe haemophiliacs were satisfactorily treated with PE VIII. PE‐E5 deserves further study as a means of preparing clinical concentrates of factor VIII.
Standardization of prekallikrein activator (PKA): the 1st British Reference Preparation for PKA
Authors: Kerry P. J. , Curtis A. D. , Paton Catherine J. , Thomas D. P.
Published: March 2008

Summary. A collaborative study on prekallikrein activator (PKA) has been carried out involving four laboratories for the purpose of establishing a British reference preparation for PKA. Samples of two plasma protein fractions (PPF) were assayed against participants’own supplies of the Bureau of Biologics Reference Preparation No. 2 (BoB 2). There was good agreement on the relative PKA activities of the preparations. One of the preparations, coded 79/572, was established as the 1st British References Preparation for Prekallikrein Activator, with an assigned potency of 78.9 units/ml.
A comparative study of carrier detection in haemophilia A by linear discriminant function
Authors: Shen Ming‐Ching
Published: March 2008

Summary. Blood samples collected from 37 definite carriers, 31 normal women and 64 possible carriers were examined for factor VIII‐related activities. Five variables: factor VIII coagulant activity (VIII:C) (X1), factor VIII‐related antigen (VIIIR:Ag) (X2), ristocetin co‐factor (VIIIR:RC) (X3), ratio of VIIIR: Ag to VIII:C (A/C) (X4) and ratio of VIIIR: RC to VIII:C (R/C) (X5), and 28 combinations of one to five variables were used to derive 28 linear discriminant functions. The calculation of discriminant function coefficient, individual discriminant score and cut‐off point, and the identification of normals or carriers were processed by the computer package of a biomedical computer program used at University of California at Los Angeles.

A comparison of 28 linear discriminant functions for carrier detection in haemophilia A has indicated that the best and simplest is y=0.11668X1 (VIII:C)‐0.06042X2 (VIIIR:Ag), (cut‐off point =2.03742). It identified 94.6% of carriers without a single misclassification in the normal group, and the overall identification rate was 97.1%. Of 29 daughters of definite carriers who had no haemophilic sons, 13, or 44.8%, could be identified as carriers.

It was found that VIIIR:RC was not as good as VIIIR:Ag for carrier detection; however, it may be concluded from this study that VIIIR:RC can be used as a supplement, if not a substitute, for VIIIR:Ag in the carrier detection of haemophilia A.
Acute lymphoblastic leukaemia cells in the diffusion chamber: change of surface phenotype during the culture period
Authors: Jäger G. , Lau B. , Pachmann K. , Dörmer P.
Published: March 2008

Summary. Peripheral blast cells from patients with acute lymphoblastic leukaemia were cultured in the diffusion chamber system. On different harvesting days the cALL antigen, surface immunoglobulin and T‐cell antigen were investigated by direct immunofluorescence. Each cell type investigated showed a different response throughout culture, the commonest change observed being development into the B‐cell axis.

Our data demonstrate that the differentiation stop of a leukaemic cell can be overcome by using the diffusion chamber system. The data therefore give some insight into the stage of developmental arrest in acute lymphoblastic leukaemia.
Haematopoietic stimulators in the serum of patients with severe aplastic anaemia
Authors: Adams J. A. , Barrett A. J.
Published: March 2008

Summary. Recent studies on sera from patients with aplastic anaemia show it to contain both stimulators and inhibitors of granulopoiesis. We have examined the serum of patients with aplastic anaemia in a short‐term liquid culture system of human bone marrow which permits CFU‐C proliferation.

Increases in CFU‐GM numbers over control values were observed with aplasia sera. All sera produced increased megakaryopoiesis, but no alteration in growth of the fibroblasts and macrophages of the adherent stromal layer. With one exception the sera had no significant direct colony stimulating activity when assayed in agar culture, but increased colony numbers were observed when the sera was incorporated into a sub‐optimal feeder layer of peripheral blood leucocytes. When aplastic serum was added to adherent cell‐depleted liquid cultures, the CFU‐C stimulating property was lost, but increased megakaryopoiesis still occurred.

These results indicate the presence of a direct‐acting thrombopoietin and an indirect‐acting stimulator of CFU‐C proliferation in the serum of patients with aplastic anaemia, which may be related to the pathophysiology of the condition.
Apparent heterogeneity of human megakaryocyte colony‐ and thrombopoiesis‐stimulating factors: studies on urinary extracts from patients with aplastic anaemia and idiopathic thrombocytopenic purpura
Authors: Kawakita Makoto , Miyake Takaji , And Susumu Kishimoto , Ogawa Makio
Published: March 2008

Summary. Megakaryocyte colony‐stimulating factor (MEG‐CSF) in the urinary extracts from patients with aplastic anaemia (AA) revealed two distinct peaks of activity on Sephadex G‐200 gel filtration with apparent molecular weights of 155 000 and 76 000. Both fractions induced significant thrombocytosis in peripheral blood and megakaryocytosis in the spleen of rats. Heterogeneity of MEG‐CSF was also found in the extracts from the urine of patients with idiopathic thrombocytopenic purpura. The higher molecular weight MEG‐CSF was significantly reduced when the gel filtration was performed under the dissociating conditions. Ion‐exchange chromatography indicated that the higher molecular weight MEG‐CSF had a different charge from the lower molecular weight MEG‐CSF. These results suggest that the apparent heterogeneity of MEG‐CSF is due to interaction of MEG‐CSF with other proteins in the urinary extracts.
Post‐natal decline of fetal haemoglobin in homozygous sickle cell disease: relationship to parental Hb F levels
Authors: Mason Karlene P. , Grandison Yvonne , Hayes R. J. , Serjeant Beryl E. , Serjeant G.R. , And S. Vaidya , Wood W. G.
Published: March 2008

Summary. The decline of fetal haemoglobin (Hb F) from birth to 6 years has been compared in a cohort of 266 Jamaican children with homozygous sickle cell (SS) disease and in 243 matched controls with a normal haemoglobin (AA) genotype. Hb F levels were significantly higher in the SS cases from 1 month onward but, unlike the normal controls, no sex difference was apparent. The Hb F levels in SS disease were significantly correlated with parental Hb F levels, suggesting that genetic factors regulating adult Hb F levels are active at earlier stages in development. Furthermore, some of these genetic determinants of Hb F production may be linked to the β‐like globin gene complex and be in linkage disequilibrium with the βs allele
Atypical presentation of acute phase, antibody‐induced haemolytic anaemia in an infant
Authors: Issitt Peter D. , Gruppo Ralph A. , Wilkinson Susan L. , Issitt Charla H.
Published: March 2008

Summary. We describe a case of ‘warm’antibody‐induced haemolytic anaemia (WAIHA) in which marked depression of red cell Rh antigen expression resulted in the patient presenting with severe anaemia but a negative direct antiglobulin test (DAT). The serum contained potent IgG Rh antibodies. Unlike two previously reported cases (Koscielak, 1980; Veer et al, 1981) in which the diagnosis of WAIHA was established before the DAT became negative, this patient presented with negative serological findings during his first episode of anaemia. As a result, the serum antibodies appeared to be allo‐ not autoimmune in nature and to be unrelated to the patient's anaemia. Confirmation of the autoimmune nature of the Rh antibodies was not possible until nearly 2 years after the first episode of anaemia.
Long‐term survival in myelomatosis; A REPORT TO THE MRC WORKING PARTY ON LEUKAEMIA IN ADULTS
Authors: Buckman R. , Cuzick J. , Galton D. A. G.
Published: March 2008

Summary. The patients entered into the Medical Research Council's First Myelomatosis Trial (MRC I) have been followed up for a minimum of 12 years, and an attempt has been made to define features recorded at presentation that might predict long‐term survival and to estimate the risk of acute myeloid leukaemia (AML) induced by treatment with either of the alkylating agents, melphalan or cyclophosphamide. In this series, the chance of a patient surviving 5 years was strongly related to the haemoglobin, blood urea concentration (BUC) and performance status at presentation. Other features, including paraprotein levels, type of heavy or light chain, bone lesions and recovery of polyclonal immunoglobulin added little useful information. Six patients died of AML, all after more than 4 years in the trial; the incidence of AML among 4‐year survivors was 10%. All six patients had been treated with continuous melphalan and the implications of this for future chemotherapy for myelomatosis are discussed.
Neutral maltase: a marker of cell differentiation in human myeloid leukaemias?
Authors: Philip Patrick Jean‐Marie , Giudicelli Jean , Delque Pascale , Cassuto Jill‐Patrice , Sudaka Pierre , Ayraud Noël
Published: March 2008

Summary. The neutral maltase activity was determined in granulocytes from normal subjects and patients with chronic or acute myeloid leukaemias. Whereas the enzyme activity is present in normal granulocytes, in chronic or acute leukaemias these cells have markedly decreased and no detectable activity respectively. These data suggest that the variations of the neutral maltase activity observed in myeloid leukaemic cells may be related either to enzymatic modifications occurring in the course of leukaemogenesis or conversely to the stage of cell differentiation reached by the neoplastic granulocytes.
Characterization of T‐lymphocyte subsets in hairy‐cell leukaemia (HCL) by monoclonal antibodies: comparison with Fcγ, Fcμ receptors and correlation with disease activity
Authors: Lauria F. , Foa R. , Gobbi M. , Pulvirenti A. , Raspadori D. , Giubellino M. C. , Tura S.
Published: March 2008

Summary. T lymphocytes from 22 patients with hairy‐cell leukaemia (HCL) were assessed on the basis of their ability to bind the Fc receptors for IgM (Tμ) or IgG (Tγ), and by the capacity to react with OKT monoclonal antibodies. T‐cell subsets defined by the presence of Fc receptors for IgM or IgG showed an overall increase in the proportion of Tγ cells and a non‐significant decrease of Tμ cells, regardless of the clinical state of the disease. Results with monoclonal antibodies showed that in patients with HCL in clinical remission T‐cell subsets were normally balanced, while in patients with active disease the distribution and absolute number of T‐cell subpopulations appeared markedly impaired, with a significant increase of OKT8 positive cells (suppressor/cytotoxic) and a significant reduction of OKT4 positive cells (helper/inducer) compared both with active disease patients and with normal controls. The OKT4+/OKT8+ ratio was also significantly reduced in patients with active disease compared with those in clinical remission and with controls (0.96 v 1.63 and v 1.94, respectively).

Our findings confirm the heterogeneity of T‐cell subset positivity defined by monoclonal antibodies and by Fcμ and Fcγ receptors and suggest that in patients with HCL the distribution of OKT4 and OKT8 positive cells is closely correlated to the clinical state of the disease.
Resistance of normal endothelium to damage by thrombin
Authors: Thomas D. P. , Merton Rosemary E. , Hiller K. F. , Hockley D.
Published: March 2008

We examined the effect of locally infused thrombin on rabbit neck veins, using autologous [111In]indium‐labelled platelets as a marker of platelet deposition. Purified thrombin at concentrations which clotted the blood in isolated veins did not lead to the deposition of labelled platelets on the vessel wall. However, when the animals were pre‐treated with aspirin (10 mg/kg), there was a marked change in the ratio of radioactive counts between control and treated segments, consistent with platelet deposition on the walls of thrombin‐treated segments.

Thrombin‐treated and control veins were also examined by transmission and scanning electronmicroscopy. Although occasional clumps of platelets were seen adhering to the vessel wall in both control and treated segments, the endothelium was essentially intact. There was no evidence of substantial denudation of the endothelium, and overall there was little morphological difference between control and treated segments. It is concluded that normal endothelium is not damaged by thrombin, and that venous thrombi develop by a direct effect of thrombin on platelets and fibrinogen, and not by thrombin‐mediated damage to the vein wall.
Comparison of the bioavailabilities and anticoagulant activities of two warfarin formulations
Authors: Stirling Yvonne , Howarth D. J. , Stockley R. , Bland R. , Towler C. M. , Harding S. M.
Published: March 2008

Changes in the British Pharmacopoeia dissolution time requirements have necessitated reformulation of warfarin sodium (‘Marevan’). The old and new formulations were compared with each other in eight healthy volunteers given a single 15 mg dose of each in a cross‐over study and also in 19 patients receiving warfarin therapy. In the volunteer study, a significant but small increase in bioavailability was observed for the new formulation. However, the effects of the two formulations on the prothrombin ratio and on clotting factors II, VII, IX and X were not significantly different. Irrespective of formulation, the greatest changes in factors II, VII and X were observed after the first dose of warfarin. With factor IX, the greatest response was observed after the second dose. The clinical study in patients confirmed that the old and new formulations of Marevan are interchangeable on a dose for dose basis. A sensitive semi‐automated warfarin assay technique is described.
Atypical cobalamin binding in the serum of congenital deficiency of transcobalamin II
Authors: Hall Charles A. , Begley James A.
Published: March 2008

The serum cobalamin (Cb1) binding patterns were described in nine children with congenital deficiency of transcobalamin II (TC II). Immunoreactive TC II was < 100 pg/ml TC II‐Cb1 equivalent in eight and 150 pg/ml in the ninth. There was neither endogenous TC II‐Cb1 (holo TC II) nor apo TC II. Thus, the defect was characterized by the absence of any binding of Cb1 to TC II either in vivo or in vitro and either non‐detectable or much reduced immunoreactive TC II. Only the serum from an untreated infant bound any added Cb1 at all, but in every sera there was binding of endogenous Cb1 to a substance of the molecular size of albumin. Native Cb1 was also bound to R binder and in some instances was incorporated into large complexes. The precise nature, cause and consequences of this atypical binding are unknown.
Receptors specific for thyroid hormones in nuclei of mammalian erythroid cells: involvement in erythroid cell proliferation
Authors: Boussios Thalia , McIntyre William R. , Gordon Albert S. , Bertles John F.
Published: March 2008

In search of evidence relating the effects of thyroid hormone on erythropoiesis to mechanisms at the chromatin level, we tested nucleated erythroid cells for the presence of specific receptors. Cells from spleens of hypoxic adult hamsters, 99% erythroid, were exposed for selected time periods to concentrations of 125I‐labelled triiodothyronine (T3) and thyroxine (T4) bracketing the physiologic ranges. Specific binding was assayed as the amount of labelled hormone displaced by subsequent addition of an excess of non‐labelled hormone. Saturable sites for both T3 and T4 were demonstrated, limited to nuclei. Binding to other sub‐cellular organelles and to plasma membrane was to low‐affinity sites only. Analysis of Scatchard plots revealed approximately 9200 binding sites per nucleus for either hormone, with a dissociation constant (Kd) of 2 · 7 nM for T3 and 20 · 5 nM for T4. The biological effect of 125I‐T3 on erythropoiesis was assayed in vitro. Erythroid colony growth was enhanced to the same extent by the radiolabelled and non‐labelled form of T3, showing that radioiodination had not altered this biological activity.
Inactivation of Kell blood group antigens by 2‐aminoethylisothiouronium bromide
Authors: Advani H. , Zamor J. , Judd W. J. , Johnson C. L. , Marsh W. L.
Published: March 2008

Human red cells incubated with a solution containing 6% 2‐aminoethyl‐isothiouronium bromide (AET) lose activity of antigens that are part of, or related to, the Kell blood group system. However, Kx antigen is not inactivated. Studies on a wide range of other blood‐group antigens show no other evidence of changes and AET appears to react specifically with red‐cell membrane structures that have Kell activity. The AET procedure produces an artificial K0 red cell that can be used in blood group serology, and allows easy recognition of antibodies that are associated with the Kell system.

AET has been used by other workers to produce a red cell that has many serological and biochemical characteristics of a PNH cell. Our studies on red cells from PNH patients have not shown any changes in Kell blood‐group antigens.
The molecular basis of alpha thalassaemia in a South African population
Authors: Mathew C. G. P. , Rousseau J. , Rees J. S. , Harley E. H.
Published: March 2008

Summary.

We have investigated the molecular basis of α thalassaemia in the so‐called ‘Cape Coloured’population of Cape Town. DNA from 17 cases was analysed by Southern blotting and hybridization with an α globin complementary DNA probe. Three types of α thalassaemia genetic determinants were detected: the 3·5 kb deletion which inactivates one α globin gene per chromosome (‐α/ haplotype), a much larger deletion which removes both α globin genes (––/ haplotype), and a non‐deletion determinant which leaves both α globin genes intact. The interaction of these determinants with each other or with the normal chromosome (αα/) produced the phenotypes α thalassaemia silent carrier, α thalassaemia trait and Hb H disease. All cases of the ‐α/ haplotype result from the rightward deletion which removes the Bgl II site between the duplicated α globin genes. The predominance of the ‐α/ haplotype (21 out of the 28 α thalassaemia determinants) over the ––/ haplotype is consistent with the low incidence of Hb H disease and the apparent absence of Hb Bart's hydrops fetalis in this population group.
ATP‐ADP compartmentation in storage pool deficient platelets: correlation between granule‐bound ADP and the bleeding time
Authors: Akkerman Jan‐Willem N. , Nieuwenhuis H. Karel , Mommersteeg‐Leautaud Marlene E. , Gorter Gertie , Sixma Jan J.
Published: March 2008

Summary.

Platelets contain two major compartments of ATP and ADP, the cytosol and the dense granules. We separated the two compartments by controlled digitonin‐induced cell lysis and measured both fractions directly in the platelets of 16 patients with storage pool deficiency. The total contents of ATP and ADP in the platelets of these patients was significantly lower than in normal controls. This was primarily caused by decreased amounts of ATP and ADP in the granule compartment, but also cytosolic ADP was low in these patients. In contrast, cytosolic ATP was not significantly decreased. The lower the amount of granule‐bound ATP and ADP, the longer was the bleeding time in these patients. The best correlation was found with granule ADP. These data may indicate that ADP stored in platelet dense granules plays a role in the arrest of bleeding.
Impaired chemiluminescence and bactericidal killing by neutrophils from patients with severe cobalamin deficiency
Authors: Skacel P.O. , Chanarin I.
Published: March 2008

Summary.

Neutrophil function was examined in 24 patients with megaloblastic haemopoiesis due to vitamin B12‐or folate deficiency. Defective bactericidal activity was demonstrated in the B12‐deficient group only and was associated with normal phagocytic activity but impaired intracellular killing. Luminol amplified luminescence was consistently low in B12‐deficient subjects with RBC counts of less than 2 × 1012/1. These defects were not seen in the folate‐deficient cases although isolated abnormalities were present in those who were also alcoholic.
Papilloedema in chronic granulocytic leukaemia
Authors: Stainsby Dorothy , Elleray Evonne , Anderson J. , Hamilton P. J. , Thompson R. B.
Published: March 2008

Summary.

Five of 75 patients with chronic granulocytic leukaemia seen over a 25 year period had papilloedema at presentation. These patients had unusually high leucocyte counts and the papilloedema may be a manifestation of leucostasis. The fundal abnormalities resolved in all five patients–in four after conventional treatment with busulphan only.
Loss of promyelocytic maturation in HL60 sublines: a potential model for leukaemia progression
Authors: Fitz‐Gibbon Linda , Price Gerald B. , Sullivan Arthur K.
Published: March 2008

Summary.

The majority of cells of the human leukaemic line HL60 appear to be promyelocytes which can be stimulated to mature into functioning neutrophils. We report here the derivation of stable subclones from the parent line which differ. Two forms of variant were obtained: (1) those with a defined lesion, selected by resistance to kill by 6‐thioguanine, which matured in the presence of DMSO and retinoic acid but not in hypoxanthine. They also continued to express peroxidase and a major granulocyte antigen, and (2) those obtained by clonal growth in DMSO which did not mature in the presence of any compound tested including hypoxanthine, DMSO, retinoic acid and actinomycin D and lacked granules, peroxidase and the granulocyte antigen. The concurrent loss of the characteristic of maturability and the phenotype of myeloid commitment suggests that the control of the two phenomena may be related. These variant cell lines provide a useful model in which to study how human leukaemic cells may become arrested in less differentiated stages of development.
The relationship between human spleen and blood erythroid burstforming units (BFU‐E)
Authors: Meytes Dina , Ortega Jorge A. , Ma Andrew , Wald Barton R. , Shore Nomie A. , Dukes Peter P.
Published: March 2008

Summary.

The influence of splenectomy on erythroid burst colony formation by peripheral blood mononuclear cells from 10 patients (four with hereditary spherocytosis, two with β‐thalassaemia major, two with Hodgkin's disease and two with idiopathic thrombocytopenic purpura) was studied. In every instance splenectomy was followed by a lowering of blood BFU‐E. The post‐splenectomy levels ranged from 0 to 30% of the preoperative levels. Mononuclear cells from the spleens of eight patients were cultured and found to contain numerous BFU‐E. The total quantity of BFU‐E in the whole blood and in the spleen of the patients was generally of the same order of magnitude. The number of splenic BFU‐E did not correlate with spleen size.

Splenic BFU‐E differed from peripheral blood BFU‐E in that they were more sensitive to erythropoietin (Ep) and in that they failed to respond to burst promoting activity (BPA) produced by preincubating the spleen mononuclear cells with phytohaemagglutinin M (PHA). In contrast, media conditioned by PHA‐treated spleen cells contained BPA active on peripheral blood BFU‐E from normal individuals. These data suggest that the spleen may have an influence on the numbers and functional properties of BFU‐E.
Granulocyte‐macrophage progenitor cell preservation at 4°C
Authors: Delforge Alain , Ronge‐Collard Elisabeth , Stryckmans Pierre , Spiro Théodore , Malarme Marie A.
Published: March 2008

Summary. Eighteen bone marrows collected from patients without haematological diseases and from normal subjects were tested for the effect of 4 d storage at 4°C on CFU‐C growth. Results indicate that unfractionated bone marrow cells may be stored at 4°C for 4 d with 97%± 8 SEM recovery of the CFU‐C evaluated by the agar culture assay. On the other hand, the same preservation procedure on peripheral blood CFU‐C of 13 normal subjects yielded only 5%± 2 SEM recovery of in vitro growth capacity.

The present results have practical implications. They might be exploited to preserve bone marrow CFU‐C for transplantation therapy or laboratory investigation. In contrast this single preservation procedure seems not appropriate for preserving blood CFU‐C.
Studies on the stability of factor VIII coagulant antigen (VIII: CAg) in the presence of VIII: C antibodies
Authors: Furlong R. A. , Peake I. R.
Published: March 2008

Summary. The stability of factor VIII coagulant antigens (VIII:CAg) at 56°C was investigated using an immunoradiometric assay for VIII: CAg. In normal or CRM+ haemophilic plasmas VIII: CAg was rapidly inactivated at 56°C. VIII: CAg in spontaneous VIII: C inhibitor plasmas and in post‐treatment samples from haemophiliacs with VIII: C inhibitor was resistant to inactivation at 56°C, indicating the presence of heat stable VIII: CAg‐anti VIII: CAg complexes.

In vitro VIII: CAg‐anti VIII: CAg complexes were formed by incubation of diluted VIII: C antibodies and normal plasma and the stability of these complexes at 56°C was studied. Haemophilic VIII: CAg antibodies formed heat stable immune complexes over a narrow range of inhibitor dilutions whilst some spontaneous VIII: CAg antibodies formed these stable complexes over a much wider range of dilutions emphasizing the difference in the properties of these antibodies.
Acquired haemostatic defects in the ill newborn
Authors: Feusner James H. , Slichter Sherrill J. , Harker Laurence A.
Published: March 2008

Summary. The kinetics and function of platelets and fibrinogen were studied in 22 ill newborns. Overall 51Cr‐platelet survival was considerably shortened (patients 2·6 d ± 1·7, adult normal 9·5 d ± 0·6, P < 0·001) while 125I‐fibrinogen surival was less severely decreased (patients 2·1 d ± 0·8, adult normal 5·1 d ± 0·4, P < 0·05).

Three patients with bacterial sepsis and one with disseminated herpes simplex had the most severely reduced platelet survival times (1·3 d ± 0·9), causing thrombocytopenia (62 ±32 × 109/l) despite production rates averaging 2 1/2 times normal. Although fibrinogen survival times were comparably reduced in these patients to 1·4 d ± 0·4, fibrinogen concentrations were normal because of compensatory increased production.

In three patients with necrotizing enterocolitis platelet and fibrinogen survival times were similarly reduced (platelets 1·6 d ± 0·6, fibrinogen 1·6 d ± 0·6) with platelet counts of 69 ± 27 × 109/l and platelet production rates of twice normal. Since their fibrinogen production was not increased, they had decreased fibrinogen concentration (1·0 ± 0·19 g/l).

In six patients with respiratory distress syndrome the kinetic results were more variable. Platelet survival was less severely affected than in the other groups and production was approximately twice normal; hence, the platelet count was maintained (177 ± 107 × 109/l). Fibrinogen in this group was slightly reduced because of decreased production in the presence of mildly decreased survival (2·7 d ± 0·7).

The two patients with cytomegalovirus infection had severe thrombocytopenia (23 × 109/l) due to a combination of decreased platelet survival (3·6 d), increased splenic pooling and no compensatory increase in marrow platelet production. Fibrinogen production was normal but its plasma concentration was moderately reduced because of a decrease in fibrinogen survival.

In many of these patients, fibrinogen dysfunction was suggested by a prolonged thrombin time and a discrepancy between fibrinogen concentration as determined by a time dependent assay and an equilibrium total clottable protein assay. Likewise, platelet dysfunction, evidenced as a prolonged bleeding time, was found in patients with RDS; some of these infants had otherwise unexplained bleeding.
Impaired protein synthesis in erythroblasts enhances their phagocytosis by macrophages
Authors: Wiener Edith , Wickramasinghe S. N.
Published: March 2008

Summary. In an attempt to elucidate mechanisms which underly ineffective erythropoiesis, we investigated the effect of impaired macromolecular synthesis in erythroblasts on their phagocytosis by macrophages in vitro. Dimethylsulphoxide‐induced murine Friend leukaemia erythroblasts were treated with inhibitors of RNA or protein synthesis and subsequently tested for their interaction with syngeneic mouse peritoneal macrophages in culture. Exposure of the erythroblasts to two reversible inhibitors of protein synthesis, puromycin and cycloheximide, enhanced their association with and phagocytosis by macrophages. The effect was evident after the drugs had caused a partial inhibition of protein synthesis and appeared to be reversible. By contrast, the treatment of erythroblasts with the inhibitor of RNA‐synthesis, actinomycin D, which caused a marked depression of RNA but not of protein synthesis, failed to affect the interaction of erythroblasts with macrophages. The results are in keeping with previous observations on human bone marrow showing impaired protein synthesis in erythroblasts in some haematological disorders characterized by a marked increase in ineffective erythropoiesis.
Folate levels and deoxyuridine suppression tests in protein‐energy malnutrition
Authors: Wickramasinge S. N. , Akinuanju O. O. , Grange Adernike , Litwinczuk R. A. C.
Published: March 2008

Summary. A group of 39 Nigerian infants and pre‐school children with protein‐energy malnutrition (PEM) have been studied. Red cell folate levels were within the range observed in 19 age‐matched healthy Nigerian children. Serum vitamin B12 levels were either normal or raised. Deoxyuridine (dU) suppression tests were performed on the bone marrow cells of 30 of the patients and were abnormal in 13. It is proposed that the abnormal dU‐suppressed values were not caused by vitamin B12 or folate deficiency and were probably a consequence of the protein deficiency. A few megaloblasts and several giant metamyelocytes were found in four of the cases of PEM; the remaining 35 cases had normoblastic erythropoiesis, sometimes with small to moderate numbers of giant metamyelocytes. All four marrow samples containing megaloblasts gave abnormal dU‐suppressed values. However, in the marrows showing normoblastic erythropoiesis there was no correlation between the presence or absence of giant metamyelocytes and the dU‐suppressed value.
Regeneration of peripheral blood cells following ABO incompatible allogeneic bone marrow transplantation for severe aplastic anaemia
Authors: Hows J. M. , Chipping P.M. , Palmer S. , Gordon‐Smith E. C
Published: March 2008

Summary. The regeneration of peripheral blood cells in six patients receiving ABO incompatible bone marrow transplants for severe aplastic anaemia has been studied. The results are compared with those of 18 similar aplastic patients treated with ABO compatible transplants. Reticulocyte recovery in the ABO incompatible cases was significantly delayed (P < 0·01) and associated with greatly prolonged red cell transfusion requirements (P < 0·01).

Peripheral blood regeneration of neutrophils, lymphocytes and platelets was also significantly delayed (P < 0·01). Platelet support was required for longer in the ABO incompatible cases (P < 0·01) but there was no increase in the incidence or severity of infections in the post transplant period.
Erythrocyte ferritin in normal subjects and patients with abnormal iron metabolism
Authors: Peters S. W. , Jacobs A. , Fitzsimons E.
Published: March 2008

Summary. Erythrocyte ferritin is about 10 times more reactive with antibody to heart ferritin than to spleen ferritin. The concentration of erythrocyte ferritin reflects the abnormal body iron status both in iron deficiency and in idiopathic haemochromatosis. Increased concentrations in β‐thalassaemia trait and primary sideroblastic anaemia may also reflect the intrinsic erythroid abnormality. Differences in the response of ‘heart‐type’ and ‘spleen‐type’ ferritin to changes of iron status suggest possible differences in metabolic function.