bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitation of red cell membrane associated immunoglobulin in children with Plasmodium falciparum parasitaemia
Authors: Jeje Oluyemi M. , Kelton John G. , Blajchman Morris A.
Published: March 2008

Summary. Erythrocyte‐associated IgG was measured on washed red cells from 26 children with P. falciparum parasitaemia using an immunoradiometric assay. The values obtained were compared with 15 age‐matched controls living in the same area who did not have malaria. The amount of red cell‐associated IgG was related to the haemoglobin concentration, degree of parasitaemia and serum immunoglobulin level. The mean red cell‐associated immunoglobulin for patients with malaria was 629 molecules per red cell (range 215–1770) which was significantly higher than the control group, who had a mean of 395 molecules per red cell (range 190–930). A statistically significant correlation was established between red cell‐associated IgG and the degree of anaemia in the infected patients. In contrast, there was no relationship between the red cell‐associated IgG and the degree of parasitaemia or the serum immunoglobulin level. These observations support the hypothesis that an immunological mechanism could be involved in the anaemia associated with malarial infections.
Inhibition of the in vitro formation of irreversibly sickled cells by cepharanthine
Authors: Ohnishi S. Tsuyoshi
Published: March 2008

Summary. A method was developed to prepare irreversibly sickled cells (ISC) in vitro under a physiological condition. By exposing sickle red cells to repeated deoxygenation‐reoxygenation cycles for 15 h at 37°C, 20–30% of the red cells formed ISC. These cells were separated from biconcave‐shaped cells by a gradient density centrifugation. The percentage of the formation of ISC was determined spectrophoto‐metrically after cells were haemolysed. Cepharanthine, a bisbenzylisoquinoline alkaloid, was found to inhibit this in vitro formation of irreversibly sickled cells by 50% at 15 μM. This concentration was much lower than that required to inhibit the in vitro sickling.
A platelet release defect induced by aspirin or penicillin G does not increase gastrointestinal blood loss in thrombocytopenic rabbits
Authors: Giles Alan R. , And Penny Greenwood , Tinlin Shawn
Published: March 2008

Summary.Gastrointestinal blood loss was compared in groups of normal and thrombocytopenic animals treated with medications known to induce qualitative platelet dysfunction. Thrombocytopenia was induced in rabbits by the intraperi‐toneal injection of busulphan dissolved in polyethylene glycol (PEG) at a dose of 60 mg/kg. Control animals received PEG alone; each group subsequently received daily intravenous injections of penicillin G, aspirin, sodium salicylate or isotonic saline. Mean daily gastrointestinal blood loss was determined by monitoring the appearance of 51Cr radioactivity in the faeces following the administration of 51Cr‐labelled erythrocytes prior to the administration of the test and control therapies. The administration of penicillin G was not associated with increased gastrointestinal blood loss in the thrombocytopenic animals as compared with the saline treated thrombocytopenic controls. Platelet aggregation studies confirmed the presence of a mild but significant defect in platelet aggregation. Aspirin produced a more pronounced defect in platelet aggregation but did not induce increased bleeding in the normal animals as compared with the controls, nor did it exacerbate the bleeding in thrombocytopenic animals. Sodium salicylate did not produce an aggregation defect and did not significantly modify gastrointestinal blood loss. It was concluded that drug‐induced qualitative platelet dysfunction does not necessarily increase bleeding through intact vessels despite previous evidence of a significant effect on platelet plug formation as monitored by the bleeding time.
Positive Coombs test in acute leukaemia
Authors: Solal‐Celigny P. , Vazeux R. , Vroclans M. , Amar M. , Herrera A. , Bernard J. F. , Boivin P.
Published: March 2008

Summary. We present the results of the immunohaematological tests performed in an unselected group of patients with acute leukaemia at the time of diagnosis, and when possible the follow‐up in remission and/or in relapse. Thirteen out of the 112 patients tested had a positive Coombs test at the time of diagnosis and, in six patients, the Coombs test became positive during remission. All the 19 positive Coombs test were of the complement type with, in 11 cases, an anti‐I antibody eluted from the patient's RBC. There was no relationship between the FAB morphologic subtype, the presence of other immune abnormalities, the course of the leukaemia and the immunohaematological abnormalities. Several hypotheses on the possible relationships between the acute leukaemias and the immunohaematological abnormalities are discussed.
Ex vivo antigen preparation for the serological detection of drug‐dependent antibodies in immune haemolytic anaemias
Authors: Salama A. , Mueller‐Eckhardt C. , Kissel Karin , Pralle H. , Seeger W.
Published: March 2008

Summary. TWO patients with severe, intravascular haemolysis due to drug‐dependent antibodies are described. The antibodies were directed against presumptive metabolites of buthiazide (International Non‐proprietary Name, butizide) and nomifensine. Their detection was possible only in the presence of ex vivo antigens (i.e. fresh serum of volunteers after ingestion of the drugs) while in vitro antigen preparations yielded inconclusive results. Both antibodies lysed normal red cells in the presence of ex vivo antigens and complement. The buthiazide‐related antibody was IgG (subclass IgGl), the nomifensine‐related antibody was IgM. We conclude that the use of ex vivo antigens is of great importance in the serological evaluation of cases with suspected drug‐dependent immune haemolysis.
Acute leukaemia in patients treated for Hodgkin's disease
Authors: PAPA G. , Mauro F. R. , Anselmo A. P. , Cimino G. , Alimena G. , Amadori S. , D'Arcangelo E. , Giannarelli D. , Bosi A. , Bellesi G. , Fiacchini M. , Mazza P. , Babini L. , Emiliani E. , Enrici R. Maurizi , Biagini C.
Published: March 2008

Fourteen acute non‐Iymphoid leukaemias (ANIL) were identified among 947 consecutive patients with Hodgkin's disease (HD) treated in five collaborating centres in Italy between January 1969 and December 1979.

Leukaemia developed 12‐118 months after the diagnosis of HD and was always preceded by a pre‐leukaemic phase. The karyotype of the leukaemic cells was studied in nine of the 14 patients and was abnormal in seven cases. Bone marrow agar cultures were performed in five of the 14 patients and were abnormal in every case.

The actuarial risk of developing ANLL at 10 years was 6.2% for combined therapy, 4.8% for salvage therapy and 2.2% for chemotherapy alone. No case of ANLL was documented among 136 patients treated with radiotherapy alone. One patient developed acute promyelocytic leukaemia following treatment with ABVD and radiotherapy. Both univariate and multivariate analyses seem to demonstrate that the induction therapy modality is a significant variable in development of secondary acute leukaemia. The recognition of a significant risk of ANLL in patients treated for HD should create changes in treatment policy.
Mechanism and characteristics of platelet activation by haematin
Authors: Neely Sara M. , Gardner Diane V. , Reynolds Nancy , Green David , Tšao Chung‐hsin
Published: March 2008

The mechanism as well as some characteristics of haematin‐induced human platelet aggregation were investigated. Haematin‐induced platelet aggregation required the presence of devalent cations; Mg2+, and to a lesser extent, Co2+, were just as effective as Ca2+ in supporting the aggregation. Mono‐ and trivalent cations were ineffective. Verapamil inhibited the aggregation. The aggregation was accompanied by thromboxane formation which could be abolished by aspirin. The release of adenine nucleotides was only slightly inhibited by aspirin. The rate of aggregation and the ultrastructure of the aggregated platelets were comparable between control and aspirin‐treated samples. It is concluded therefore that haematin‐induced aggregation is not dependent on platelet prosta‐glandin synthesis. Haematin induced binding of fibrinogen to platelets, and failed to aggregate thrombasthenic platelets. These findings indicate that haematin may induce platelet aggregation by promoting influx of divalent cations in association with increased fibrinogen binding and release of adenine nucleotides.
Cigarette smoking and platelet adhesion
Authors: Pittilo R. M. , Clarke J. M. F. , Harris D. , Mackie I. J. , Rowles P. M. , MACHIN S. J. , Woolf N.
Published: March 2008

Non‐abraded rabbit endothelium has been exposed to human blood taken from male non‐smoking volunteers before and after the smoking of two medium tar cigarettes, in an in vitro system using a Baumgartner chamber. In each case the blood was allowed to circulate for 10 min at a constant flow rate. Blood from 10 volunteers has been tested in this way. Scanning electron microscopy of the endothelial surfaces demonstrates large numbers of adherent platelets when ‘post‐smoking blood’ is used, but very few and in some cases none with the ‘pre‐smoking’ blood. As a further control to ensure that this phenomenon did not occur as a result from changes in the vessel related to the time during which it had been removed from its normal physiological environment, blood from further non‐smoking volunteers was passed over seven of the remaining pieces of vessel at the completion of these runs. Platelets were either absent or very few in number, as with the pre‐smoking samples.
Efficacy of porcine factor VIII in the management of haemophiliacs with inhibitors
Authors: Ciavarella N. , Antoncecchi S. , Ranieri P.
Published: March 2008

We report our experience with polyelectrolyte‐fractionated highly purified porcine factor VIII concentrate (Hyate:C). Porcine factor VIII concentrate was used to treat 14 haemorrhagic episodes including seven severe haemarthroses, three severe haematomata, two episodes of oral bleeding, one traumatic and the other after multiple dental extractions and two life‐threatening intestinal haemorrhages. Altogether 60 infusions of Hyate:C were given to five haemophiliacs with inhibitors. At the time of the first infusion with porcine factor VIII the anti‐human inhibitor level ranged from 60 to 2‐5 modified Bethesda units/ml (MBU 4 h incubation). The porcine cross‐reactivity of these inhibitors was 25‐6% and 5‐4% of the human inhibitor level in two patients and scarcely measurable in the other three patients. We injected an amount of porcine factor VIII concentrate corresponding to the calculated porcine neutralizing units plus the units required for haemostasis. The clinical efficacy was excellent and no adverse effects were encountered, apart from two episodes of mild pyrogenic reactions well controlled by hydrocortisone. The anamnestic antibody response against human factor VIII was of slight degree in all cases, while the porcine cross‐reactivity showed no significant variation. Our results emphasize the role of porcine factor VIII in the treatment of haemophiliacs with inhibitors.
Effect of complement on the viscoelastic properties of human erythrocyte membrane
Authors: Sung K.‐L. P. , Freedman J. , Chabanel A. , Chien S.
Published: March 2008

Summary. Using the micropipette technique, we examined the viscoelastic properties of the red blood cell (RBC) membrane which had been strongly coated with various components of complement (primary C3b, C3d, C4b, C4d) in vitro. The membrane elastic modulus (E), the viscosity index of the initial rapid phase of deformation (ηD1), the viscosity of the later slow phase of deformation (ηD2) and the viscosity of the recovery phase (ηR) were determined. Compared to control non‐complement coated RBCs, RBCs coated with C3d, either alone or with other complement components, showed significant increase in the values for elasticity and viscosities. Thus C3d fixation resulted in decreased membrane deformability. Changes in membrane viscoelasticity due to bound C3d were not enhanced by bound C4b, C4d, C5, factor Bb or ηp; presence on RBC membrane of the latter two complement components may partially reverse the effect of C3d fixation. Lipid fluidity of RBC membrane, examined by fluorescence depolarization, increased with fixation of all complement components except C5. These complement‐induced changes in membrane viscoelastic properties have potential pathophysiological and clinical implications. The data suggest that extravascular sequestration of human RBCs may be explained in part by increased membrane rigidity resulting from C3d fixation.
A study of the effects of treating platelets with paraformaldehyde for use in the platelet suspension immunofluorescence test
Authors: Magee J. M.
Published: March 2008

Summary. Discrepant results when paraformaldehyde (PFA) treated and untreated platelets were used in parallel in the platelet suspension immunofluorescence test (PSIFT) (von dem Borne et al, 1978) prompted further investigation of the sera of a group of patients suffering from chronic renal failure (CRF). The demonstration of a positive result in the PSIFT when only PFA treated platelets were used appears to be linked to the N like red cell antibody described in some patients suffering from CRF.
The effect of liver disease on factors V, VIII and protein C
Authors: Kelly D. A. , O'Brien F. J. , Hutton R. A. , Tuddenham E. G. D. , Summerfield John A. , Sherlock S.
Published: March 2008

Summary. The components of the factor VIII complex were estimated by immuno‐ and bioassays in 85 patients with liver disease. The plasma concentrations of the antigens were elevated in 65% (VIII:CAg) and in 76% (VIIIR:Ag) of patients while the biological activites were elevated in only 14% (VIII:C) and 15% (VIII:RiCof). There was no correlation with C‐reactive protein, used as a measure of an acute phase reaction (χ2=0·7; P=0·1); or with severity of liver disease as judged by prothrombin ratio (P=1·0) but highest values were observed in patients with cholestatic liver disease. Following parenteral vitamin K there was a significant fall in both the biological activity of VIIIC (36%) and of VIII:CAg (38%) in 13 vitamin K deficient patients (P<0·001) but no change in 23 vitamin K replete patients or in the VIIIR:Ag levels in either group.

Factor V levels were lower in patients with parenchymal liver disease (0·54±0·1 units/ml, mean ±SEM, n=12; normal range 0·5–1·5 units/ml) than in patients with extrahepatic cholestasis who were vitamin K deficient (1·2 ± 0·1 units/ml, P<0·0001). The levels of protein C antigen, the vitamin K dependent protease which inactivates factors VIII:C and V, was at the lower end of the range in both groups (0·7±0·1, mean ±SEM, n= 18, normal range 0·74–1·4 units/ml). There was no significant change in either protein C antigen or factor V following vitamin K.

The discrepancy between the biological activity of factor VIII and the antigen levels could represent accumulation of partially degraded factor VIII or production of a hypoactive form. There is no evidence that the reduction in VIIIC and VIII:CAg following vitamin K was mediated by protein C.
The human leucocyte‐common antigen: differential expression of framework and restricted antigenic determinants on early haemopoietic progenitors
Authors: Katz Fay E. , Lam Grace , Ritter Mary A.
Published: March 2008

Summary.Monoclonal antibodies have been raised against human LC determinants. One, F10.89.4, recognizes a ‘framework’ epitope on all LC molecules; the other, F8.11.13, recognizes a ‘restricted’ epitope present on only a subset of these molecules which are found mainly on B and a subpopulation of T cells. A previous study of leukaemias showed that some early lymphoid and myeloid leukaemic cells totally lack LC (35% of ALLs and AMLs are F10.89.4‐, F8.11.13‐). In contrast, a proportion of myeloid leukaemias carried both ‘framework’ and ‘restricted’ epitopes (30% AMLs and AMMLs are F10.89.4+, F8.11.13+). To determine whether comparable heterogeneity exists in normal bone marrow we have analysed LC expression during haemopoiesis, using FACS separated populations andin vitroprogenitor assays. Our data show that the great majority of haemopoietic progenitors express the LC ‘framework’ epitope. These can be separated by size into myeloid (large) and lymphoid (small) progenitor populations. However, very few myeloid progenitors (11% CFU‐GM, 6% CFU‐GEMM) express the additional ‘restricted’ LC F8.11.13 epitope. Most F8.11.13+progenitors are CFU‐lymphoid; these generate both T and B lymphocytes, but show a preference for the B lineage. Thus there is some molecular heterogeneity of LC during normal haemopoiesis, but this is far less extensive than that found in leukaemias.
Separation of malignant plasma cells from the bone marrow of patients with myelomatosis
Authors: Ali F. M. K. , Weetman A. P. , May A.
Published: March 2008

Summary Complement‐mediated lysis of bone marrow cells from patients with myelomatosis using a rabbit antiserum raised against normal peripheral blood mononuclear cells was found to greatly enrich the abnormal plasma cells. Cellular morphology was good and the cells were able to synthesize and secrete paraprotein. This was found to be a quick and useful method of preparing myeloma plasma cells for further studies of their metabolic properties.
The relationship between vessel wall injury and venous thrombosis: an experimental study
Authors: Thomas D. P. , Merton R. E. , Wood R. D. , Hockley D. J.
Published: March 2008

Summary The relative importance of stasis, vessel wall damage and hypercoagulability in the pathogenesis of venous thrombosis remains disputed. While the combination of local vascular stasis and systemic hypercoagulability can be shown to produce experimental thrombi within a few minutes, it has been claimed that vessel wall damage is also a necessary component of venous thrombogenesis. In this experimental study, mechanical crushing of the jugular veins produced patchy areas of denuded endothelium, with underlying vessel wall oedema, as seen by ultrastructural examination. While the exposed subendothelium became covered with activated platelets following restored blood flow, there was no fibrin formation after 5 min. When blood flow was restored for 60 min following the crush injury, white cells could be seen adhering to and migrating through the vessel wall, although there was still no visible fibrin. The addition of venous stasis for 20 min did not lead to the formation of stasis thrombi in association with the damaged areas. The present experiments demonstrate that, far from there being subtle endothelial damage contributing to acute venous thrombosis, even readily demonstrable damage is a poor stimulus to fibrin formation at local sites of vessel wall injury.
Low‐dose ARA‐C fails to enhance differentiation of leukaemic cells
Authors: Perri Robert T. , Weisdorf Daiel J. , Oken Martin M.
Published: March 2008

Summary Nine patients with acute myelogenous leukaemia were treated with low‐dose ARA‐C (10 mg/m2, q 12 h) for a planned 21 d. Complete remission was attained in only one patient (11.1%). Definite cytoreductive effect was seen in four additional patients. There was one treatment‐related death. Haematologic toxicity occurred in all nine patients with severe thrombocytopenia most prominent. Severe hepatotoxicity precluded further ARA‐C treatment in one patient. Because of toxicity only two patients were able to complete their scheduled 3 week courses of low‐dose ARA‐C. No evidence of ARA‐C induced differentiation of leukaemic cells was noted on follow‐up bone marrow examination during or shortly after the treatment course. The utility and indication for low‐dose ARA‐C therapy of AML remains to be determined.
Leukaemic transformation of engrafted bone marrow cells
Authors: Smith Janice L. , Heerema Nyla A. , Provisor Arthur J.
Published: March 2008

Summary

Recurrent leukaemia following bone marrow transplantation is most often due to the regrowth of original host leukaemia cells, but may also be due to the malignant transformation of normal donor marrow cells after transplantation into a leukaemia patient. We report the ninth case of malignant change in cells of donor origin in a 12‐year‐old boy who was originally diagnosed as having Ph1+ CML. He remained Ph1+ during lymphoid blast crisis. After transplantation with marrow from a cytogenetically normal sister, he relapsed to Ph1– ALL in the female donor cells. The marrow showed a mixed karyotype of 46,XX/46,XX,inv(9)(p12q12). It would appear that, haematologically, the patient showed different manifestations of the same disease state. Cytogenetically, however, the pre‐ and post‐transplant leukaemias were different.
Philadelphia chromosome‐negative chronic myelogenous leukaemia: a morphological reassessment
Authors: Pugh William C. , Pearson Marilyn , Vardiman James W. , Rowley Janet D.
Published: March 2008

Summary

Morphological re‐examination of 25 cases classified as Ph1‐negative chronic myelogenous leukaemia (CML), with particular attention to the recent French‐American‐British (FAB) group proposals for the diagnosis of the myelodysplastic syndromes, led to reclassification of all but one of these cases. Upon review of pretreatment material, seven of the 25 cases (28%) were considered to represent myeloproliferative and reactive conditions other than CML. Of the remaining 18 cases, 17 (94%) were reclassified as myelodysplastic syndromes (MDS). These included one case of refractory anaemia (RA), three of refractory anaemia with excess of blasts (RAEB), four of RAEB in transformation (RAEBT), and nine of chronic myelomonocytic leukaemia (CMMoL). Haematological findings in these 17 patients were compared to those in 50 randomly selected patients with Ph1‐positive CML. Whereas an absolute basophilia in the peripheral blood was a nearly constant feature in the Ph1‐positive group, it was lacking in all but one of the patients with myelodysplastic syndromes. Differences in the pattern and degree of dysplasia were also noted. Only one of the 25 cases studied was considered morphologically and clinically indistinguishable from Ph1‐positive CML. It appears that Ph1‐negative CML constitutes a heterogeneous group of prognostically distinct disorders and the, in most instances, careful morphologic examination will permit precise classification.
Ultrasonic demonstration of clinical and subclinical hepatic venous thrombosis in paroxysmal nocturnal haemoglobinuria
Authors: Birgens H. S. , Hancke S. , Rosenklint A. , Hansen N. E.
Published: March 2008

Summary. Extensive hepatic venous thrombosis was demonstrated by ultrasonic scanning in three patients with paroxysmal nocturnal haemoglobinuria (PNH). The ultrasonography results were confirmed by X‐ray venography. Two of these patients were without clinical symptoms of hepatic involvement apart from a slight increase in transaminases. This study indicates, firstly, that ultrasonic scanning is a rapid and reliable diagnostic tool in monitoring patients for this serious and often fatal complication, and, secondly, that hepatic venous thrombosis may be a more common complication in PNH than previously assumed.
Changes in fluidity and composition of erythrocyte membranes and in composition of plasma lipids in Type I diabetes
Authors: Bryszewska Maria , Watala Cezary , Torzecka Wieslawa
Published: March 2008

Summary. Changes in the fluidity and composition of human erythrocyte membranes and in the composition of plasma in Type I (insulin‐dependent) diabetes were investigated. The increased microviscosity of diabetic erythrocyte membranes provide unambiguous proof of the structural deterioration of erythrocyte membranes in diabetes. It seems most likely that enhancement of the membrane cholesterol/phospholipid ratio is the main reason for decreased membrane fluidity in diabetes. A distinct correlation between membrane cholesterol/phospholipid ratio, plasma cholesterol content and membrane fluidity was found. Composition and structural changes in erythrocyte membranes and compositional changes in plasma lipids may contribute to the development of diabetic complications in diabetes.
Treatment of adult patients with idiopathic thrombocytopenic purpura with intravenous immunoglobulin: effects on circulating T cell subsets and PWM‐induced antibody synthesis in vitro
Authors: Dammacco F. , Iodice G. , Campobasso N.
Published: March 2008

Summary. Eight adult patients with idiopathic thrombocytopenic purpura (ITP) were given two 5‐d courses of intermediate (250 mg/kg body weight/d) to high dose (400 mg/kg body weight/d) intravenous infusions of human plasmin‐cleaved Ig, at 15–30 d intervals. Three patients also were given single booster infusions (400 mg/kg body weight for 1 d) of a different preparation, S‐sulfonated Ig. As expected, significant though transient rises in the platelet count were consistently observed in all patients. The mean platelet count increase was 95 600/mm3 after the first course, and 143 500/mm3 after the second course. Similar effects of lower magnitude were obtained several times in the patients given single booster doses. In three patients, platelet‐bound IgG levels were decreased in association with Ig therapy.

Phenotypic analysis of T cell subsets before starting Ig therapy and at the end of the second high dose course of intravenous Ig treatment revealed significant reductions in the proportion of T4 + lymphocytes in five patients and relative increases in the percentage of T8 + cells after therapy. As the overall proportion of T3 + cells remained unchanged, the T4 +/T8 + ratio was therefore decreased. The total number of circulating lymphocytes was also decreased following therapy. In addition, PWM‐driven Ig biosynthesis in vitro was significantly impaired after therapy in most patients, the capacity to synthesize IgG being mainly affected. It is concluded that, in addition to the reported transient blockade of the reticuloendothelial system, non‐specific suppression of polyclonal Ig biosynthesis induced by the high dose Ig infusions also contributes to the net increase in platelet count.
Pseudothrombocytopenia: a cold autoantibody against platelet glycoprotein GP IIb
Authors: van Vliet H. H. D. M. , Kappers‐Klunne M. C. , Abels J.
Published: March 2008

Summary. Increased binding of IgM to donor platelets was detected in serum of a patient demonstrating the phenomenon of pseudothrombocytopenia. The elevated IgM binding was dependent on EDTA concentration and temperature, and could not be demonstrated when platelets of patients with Glanzmann's disease were used. Immunoblotting and crossed immunoelectrophoresis showed that the IgM antibody reacted with platelet glycoprotein GP IIb. Evidence is presented that the antigenic binding site on GP IIb is made accessible to the antibody by means of the effect of EDTA on the Ca2+ dependent GP IIb/IIIa complex.
Lymphocyte doubling time in chronic lymphocytic leukaemia: analysis of its prognostic significance
Authors: Montserrat Emilio , Sanchez‐Bisono Juan , Viñolas Nuria , Rozman Ciril
Published: March 2008

Summary.In 100 untreated patients with chronic lymphocytic leukaemia (CLL) lymphocyte doubling time (LDT) has been investigated in relationship with clinical stages, bone marrow histological patterns, treatment‐free period and survival. Although partially correlated with clinical stages and bone marrow patterns. LDT has a clear prognostic significance by itself: whereas a LDT of 12 or less months identifies a population of patients with poor prognosis, a LDT higher than 12 months is indicative of good prognosis as substantiated by a long treatment‐free period and survival. This simple parameter can be useful in the clinical management of CLL patients.
Orally active α‐ketohydroxy pyridine iron chelators intended for clinical use: in vivo studies in rabbits
Authors: Kontoghiorghes George J. , Hoffbrand A. Victor
Published: March 2008

Summary Increased daily iron excretion from iron overloaded, 59Fe lactoferrin labelled rabbits was observed following the intragastric administration of 1,2‐dimethyl‐3‐hydroxy pyrid‐4‐one (L1) or 1‐ethyl‐2‐methyl‐3‐hydroxy pyrid‐4‐one (L1‐NEt) at doses of 200 mg/kg. 59Fe excretion induced by these drugs was predominantly faecal and was comparable to that caused by similar doses of subcutaneous or intramuscular desferrioxamine. The effectiveness of the two α‐ketohydroxy pyridine chelators was confirmed by repeated administration, intragastrically or by subcutaneous or intramuscular injection, to the same or other rabbits. Examination of the urine during the administration of the chelators revealed their high specificity for iron but not for copper, zinc, calcium or magnesium.
The value of a 51Cr platelet lysis assay as crossmatch test in patients with leukaemia on platelet transfusion therapy
Authors: Van Der Velden Ko J. , Sintnicolaas Kees , Löwenberg Bob
Published: March 2008

Summary Current platelet crossmatch testing still results in a significant percentage of false positive or false negative results in oncological patients during platelet support. A 51Cr platelet lysis assay was used for the detection of platelet alloantibodies. We determined the predictive value of this assay as crossmatch procedure on 28 occasions in 14 patients who received random single donor platelet transfusions. To deal with the problem of spontaneous lysis we included a panel of 10 control sera from normal individuals and applied several methods of statistical analysis to these data. It appeared that the use of only one control serum was sufficient when the percentage relative counts was used as the criterion variable, which is of advantage in the practical application of the test. The test values were retrospectively compared with the clinical transfusion response, determined as the 1 h post‐transfusion platelet recovery. The 51Cr platelet lysis crossmatch showed false negative results in 1/21 cases and false positive results in 1/7 cases. These data indicate that the 51Cr platelet lysis assay adds a useful dimension to the solution of the problem of selecting compatible platelet donors. Spontaneous lysis of target platelets appeared not to be a problem in the interpretation of test results.
Lack of pathogenetic role of proteins C and S in thrombosis associated with asparaginase‐prednisone‐vincristine therapy for leukaemia
Authors: Pui Ching‐Hon , Chesney Carolyn M. , Bergum Peter W. , Jackson Carl W. , Rapaport Samuel I.
Published: March 2008

Summary. Plasma levels of protein C and protein S antigens were measured in eight children who developed thrombosis following asparaginase‐prednisone‐vincristine treatment for acute lymphoblastic leukaemia and in nine similarly treated children without this complication. Protein C antigen levels were below normal in three of the eight patients with thrombosis and in three of the nine patients without the complication (P= 0‐38). Low protein S antigen levels were found in five of six patients with thrombosis and in two of seven patients without thrombosis (P=0‐10). Plasma factor IX and factor X antigen levels, other vitamin K dependent factors, were also measured in the two groups of patients. In general, reduced levels of protein C, protein S or both antigens (anticoagulant vitamin K dependent proteins) were associated with reduced levels of factor IX, factor X, or both of these factors (procoagulant vitamin K dependent clotting proteins). The ratios of protein C and protein S antigens to each other and to factor IX and factor X antigens did not differ between the two groups. Thus, there is no clear evidence that reduced levels of protein C and (or) protein S cause thrombosis in leukaemia patients treated with this drug combination.
Inverse relationship between megakaryocyte buoyant density and maturity
Authors: Jackson Carl W. , Steward Shirley A. , Brown L. Keith , Look A. Thomas
Published: March 2008

Summary. We examined the relationship between rat megakaryocyte buoyant density and maturation stage in continuous Percoll density gradients. An average of 88% of megakaryocytes had buoyant densities <1–054 g/ml. There was an inverse relationship between megakaryocyte buoyant density and maturation. Morphologically mature forms comprised 90% of the megakaryocytes with buoyant densities of 1.030–1.033 g/ml. In contrast, immature morphology was present in three‐quarters of megakaryocytes with buoyant densities of 1.042–1.046 g/ml. These morphological findings were confirmed by [3H]thymidine labelling studies. Cell viability assessed by trypan blue exclusion was highest among more dense megakaryocytes of which the majority were immature. The lowest trypan blue exclusion was found in the less dense, predominantly mature megakaryocytes indicating that these cells are more susceptible to membrane damage during marrow suspension. Megakaryocyte DNA content distributions and platelet antigen levels, determined by two‐colour flow cytometry, were also related to megakaryocyte density; the more dense megakaryocytes showed an approximately two‐fold higher proportion of 8N cells and less platelet antibody binding than did less dense megakaryocytes. These studies suggest that megakaryocytes can be fractionated according to their buoyant densities into immature and mature populations suitable for molecular studies of differentiation.
Acute lymphoblastic leukaemia in a child with familial Pelger‐Huet anomaly
Authors: Oneson Ruth , Sabio Hernan , Innes Donald J.
Published: March 2008

A case of familial Pelger‐Huet anomaly in a 3‐year‐old boy with acute lymphoblastic leukaemia is described. This unique association was investigated through serial observations of the peripheral blood smear and bone marrow obtained during the child's treatment with chemotherapy. The average lobe index (ALI) of neutrophils was 1·42 with no three‐lobed forms at the time of the initial diagnosis. During antimetabolite maintenance therapy with 6‐mercaptopurine and methotrexate the ALI was 1·87 and three‐lobed forms were present. The behaviour of the P‐HA cells to heat induced radial hypersegmentation of the nucleus was examined in other family members. The mechanism by which heat and folate deficiency induce neutrophil segmentation is preserved in the familial Pelger‐Huet anomaly.
Heterogeneity of IgG1 monoclonal anti‐Rh(D): an investigation using ADCC and macrophage binding assays
Authors: Armstrong Sylvia S. , Wiener Edith , Garner S. F. , Urbaniak S. J. , Contreras Marcela
Published: March 2008

Three monoclonal IgG1 anti‐Rh(D), UCH D4, ARC 7D5 and UKTS FC3, produced by Epstein‐Barr virus transformed cells from Rh(D)‐sensitized individuals, were compared with polyclonal single donor anti‐D sera and therapeutic immunoglobulin preparations in antibody dependent cellular cytotoxicity (ADCC) and macrophage binding tests. When assayed at equal anti‐D concentrations monoclonal antibodies varied considerably in their ADCC and macrophage binding activities: only UKTS FC3 showed significant activity in both assays, but these were substantially lower than those of the polyclonal anti‐D sera and immunoglobulins. When examined in different combinations the monoclonal antibodies showed little synergism in mediating red cell destruction by the effector cells. Factors which might contribute to the diverse ADCC and macrophage binding activities of the monoclonal anti‐Ds of the same IgG subclass are discussed.
Platelet antibodies in systemic lupus erythematosus
Authors: Kaplan C. , Champeix P. , Blanchard D. , Muller J. Y. , Cartron J. P.
Published: March 2008

Summary. In systemic lupus erythematosus (SLE), the precise cause of the thrombocytopenia is unknown. Since platelet associated IgG is increased in many patients, it has been suggested that the destruction of platelets might be dependent on specific antibodies.

In nine patients with SLE, platelet associated immunoglobulins were found together with free serum antibody which bound to platelets from all normal subjects.

Using an immunoblotting technique with membrane proteins from normal platelets incubated with patient sera, target antigens were localized on a band of mol wt 108 000 in two cases (B. and N.) and on a band of mol wt 66 000 in a third (M.). When the same technique was applied to autologous platelets of patient N., autoantibody binding to the protein of mol wt 108 000 was demonstrated. The antigenic determinants were not removed from the platelets by enzyme treatment or by disulphide bond reduction, and were localized in the cytoplasmic fraction of the platelets.
A new familial‘giant platelet syndrome’ with structural, metabolic and functional abnormalities of platelets due to a primary megakaryocyte defect
Authors: Greaves M. , Pickering C. , Martin J. , Cartwright I. , Preston F. E.
Published: March 2008

Summary. We have investigated platelet morphology, function and biochemistry in a family affected by dominantly inherited congenital thrombocytopenia with giant platelets. A defect of aggregation was defined with evidence of disturbed fatty acid distribution in platelet membrane phospholipids and impaired arachidonic acid mobilization. Release of 5‐hydroxytryptamine was normal. Platelet ultra‐structure was grossly abnormal and volume analysis revealed small as well as giant forms. Bone marrow megakaryocytes were morphologically abnormal and the distribution of mean nuclear ploidy atypical, suggesting the production of abnormal platelets due to a primary megakaryocyte disorder. The features of this condition are distinct from those previously described in familial thrombocytopenia and constitute a new‘giant platelet syndrome’. The qualitative and quantitative platelet defects may be secondary to a disturbance of megakaryocyte cytoplasmic fragmentation.
Antithrombin III Northwick Park: demonstration of an inactive high MW complex with increased affinity for heparin
Authors: Lane D. A. , Flynn A. , Ireland H. , Erdjument H. , Samson D. , Howarth D. , Thompson E.
Published: March 2008

Summary. It has been shown previously that antithrombin III Northwick Park has reduced ability to inactivate thrombin and is characterized by an additional anodal component on crossed immunoelectrophoresis (Howarth et al. 1985). We have applied plasma from an affected family member to heparin‐Sepharose and eluted the antithrombin III with a salt gradient. Evidence is presented that a variant component has slightly higher affinity for heparin than normal antithrombin III. Furthermore, this variant component is present in plasma as an ∼ 120000 MW inactive antithrombin III complex that can be reduced with dithiothreitol to MW ∼ 60 000, indicating disulphide bridging. Using ionexchange chromatography, the inactive complex has been isolated and shown to migrate in the same position as the anodal peak on crossed immunoelectrophoresis.
Direct analysis of plasma fibrinogen‐derived fibrinopeptides by high‐performance liquid chromatography: investigation of nine congenital fibrinogen abnormalities
Authors: Southan Christopher , Thompson Elizabeth , Lane David A.
Published: March 2008

Summary. A simple method has been developed for the rapid analysis of fibrinopeptides contained on fibrinogen in small anticoagulated plasma samples. Following incubation with thrombin the plasma is diluted, boiled and then studied by high performance liquid chromatography (HPLC). The three forms of FPA (AP, A, AY) and two forms of FPB (B, des Arg B) can be identified and quantified in samples of less than 200 μl. Additionally, the FPB peak height can be used to measure the plasma fibrinogen level. This method has been used to screen plasma samples with abnormal clotting times for possible congenital fibrinogen abnormalities. Results of the study of nine unrelated cases are presented. Four cases of congenital dysfibrinogenaemia were diagnosed directly from HPLC analysis alone. Fibrinogen Sheffield and Paris VI were identified as AαArgl6→His substitutions and fibrinogens London VI and Madrid II were found to be heterozygous for an unknown substitution preventing thrombin cleavage at AαArg16. A case of dysfibrinogenaemia (fibrinogen Ashford) with a normal fibrinopeptide release stoichiometry was confirmed to have a primary polymerization abnormality using purified fibrin monomers. Similarly, a case of hypodysfibrinogenaemia (fibrinogen London V) had normal fibrinopeptides and a fibrin polymerization abnormality. In one case of hypofibrinogenaemia and two cases of afibrinogenaemia, no fibrinopeptide or functional abnormalities could be definitely established. This rapid and simple method of fibrinopeptide analysis is recommended for screening of plasma samples taken from patients suspected of having abnormalities of fibrinogen synthesis.
Comparison of the platelet pro‐aggregatory effect of conventional unfractionated heparins and a low molecular weight heparin fraction (CY 222)
Authors: Barradas M. A. , Mikhailidis D. P. , Epemolu O. , Jeremy J. Y. , Fonseca V. , Dandona P.
Published: March 2008

Summary. Two unfractionated heparins (UH), a porcine intestinal mucosal heparin (PIM), a bovine lung heparin (BLH) and a low molecular weight heparin (LMWH), CY 222, were assessed for their capacity to enhance platelet aggregation in vitro. Their potential proaggregatory effect was investigated in four systems: (a) enhancement of submaximal platelet aggregation induced by conventional agonists in platelet rich plasma and (b) in whole blood; (c) reversal of inhibition of platelet aggregation induced by iloprost, a stable analogue of prostacyclin; (d) the direct aggregatory effect of these anticoagulants on hyperactive platelets prepared from patients with severe peripheral vascular disease or anorexia nervosa. Whereas BLH and PIM, at therapeutic concentrations, had a proaggregatory effect in all four systems, CY 222 had no significant effect when compared with the controls. BLH was more potent than PIM in three of the four systems studied. These observations confirm that conventional UH are more proaggregatory than LMWH, and thus the latter may be potentially safer. These observations are also consistent with the fact that BLH administration causes thrombocy‐topenia more frequently than PIM. The direct activation by UH of platelets from patients not previously exposed to heparin also challenges the hypothesis that heparin‐induced platelet activation and thrombocytopenia is solely mediated by classical heparin‐dependent immune mechanisms.
Molecular diagnosis of haematological disorders using DNA from stored bone marrow slides
Authors: Fey M. F. , Pilkington S. P. , Summers C. , Wainscoat J. S.
Published: March 2008

Summary. A method is described for the extraction of high molecular weight DNA from bone marrow slides which have been stored at room temperature for more than 10 years. This technique widens the scope of molecular analysis of haematological malignancies to include the investigation of cases where the original malignant cells are not otherwise available.
Clinical and cytogenetic features of familial erythroleukaemia
Authors: Lee Edward J. , Schiffer Charles A. , Misawa Shinichi , Testa Joseph R.
Published: March 2008

A family is described in which six members developed acute nonlymphocytic leukaemia (ANLL) over the past 1 5 years, all morphologically FAB M6. Five affected individuals (ages 54‐73) are members of a single sibship, the sixth (age 31) was the son of one of the affected sibs. The family lives in a rural area, and no environmental hazard has been identified. One of the six patients never resided in the same geographic area as the others. Three patients with leukaemia died without chemotherapy, two died shortly after the initiation of chemotherapy and the most recent patient never achieved remission, surviving 10 months. Bone marrow specimens from the two most recent patients were analysed for cytogenetic abnormalities using chromosome banding techniques. In addition, skin fibroblasts were examined in a single patient. The fibroblasts had a normal karyotype. Bone marrow cells from both patients had complex abnormalities. Some similarities were observed, including: (1) hypodiploidy; (2) loss of one chromosome 20; (3) the presence of multiple marker chromosomes. In each case one marker appeared to involve the‘missing’no. 20 with an alteration of the long arm—loss (20q —) in one patient and gain (20q +) in the other. Peripheral blood lymphocytes were grown in folate deficient medium, but no evidence for folate sensitive fragile sites was found. Marrow chromosomes from a third leukaemic sibling were examined without banding techniques in 1976 and the karyotype was 45.XY, — 18, — F(19 or 20), ‐I‐marker. No specific cytogenetic finding was common to the three patients studied except for the loss of an F group chromosome. This family is unique in the literature with six cases of familial leukaemia of the same morphologic subtype, and the cytogenetic findings suggest that loss or rearrangement of part of the long arm of a single chromosome 20 may have occurred in each of the three patients examined.
Association of thalassaemia intermedia with a beta‐globin gene haplotype
Authors: Thein S. L. , Wainscoat J. S. , Sampietro M. , Old J. M. , Cappellini D. , Fiorelli G. , Modell B. , Weatherall D. J.
Published: March 2008

We have identified 14 Asian patients with homozygous β° thalassaemia who had a mild clinical disorder related to an augmented production of haemoglobin F. None of their parents had an elevated level of Hb F. Restriction fragment length polymorphism analysis of the β‐globin cluster of these patients and a control group of Asian thalassaemia major patients showed that 6/14 of the thalassaemia intermedia patients were homozgyous for a particular 5′β‐globin haplotype (−+−++), in contrast to 1/42 of the thalassaemia major patients. Furthermore, the —+—++β haplotype is also associated with amelioration of disease severity in β thalassaemia in an Italian population. This β haplotype is linked to a DNA sequence variation 5′ (at position — 158) to the cγ globin gene which can be detected by the presence (+) of an Xmn I restriction enzyme site. The possible role of the Xmn I‐γ polymorphism in relation to this variant HPFH is discussed. We conclude that much of the observed clinical variability of β thalassaemia can now be explained by the inheritance of β thalassaemia chromosomes with different propensities for fetal haemoglobin production.
Depressed fibrinolysis in patients with acute leukaemia
Authors: Guarini A. , Mussoni L. , Gugliotta L. , Chetti L. , Niewiarowski T. , Catani L. , Macchi S. , Donati M. B. , Tura S.
Published: March 2008

The fibrinolytic system was studied in 46 patients with acute leukaemia at diagnosis. Untreated patients (with the sole exception of the M3 subgroup) showed an inhibition of fibrinolytic activity, measured by the euglobulin lysis time and area. This inhibition was accompanied by reduced t‐PA antigen and t‐PA inhibitor activity. No correlation was found between the above‐mentioned fibrinolytic parameters and the biochemical haematological values considered, nor with clinical and/or laboratory features of DIC. fever, liver failure. The decrease in immunological plasminogen and functional α2‐antiplasmin, showed a significant correlation with the presence of clinical and/or laboratory signs of DIC, as diagnosed on the basis of concomitant increase in fibrin monomers, plasmatic fibrinopeptide A and serum FDP.
Altered expression of platelet surface glycoproteins during storage
Authors: Dhar Animesh , Ganguly Pankaj
Published: March 2008

Human blood platelets were stored in autologous plasma at 4°C or 22°C and their surface changes were probed with three lectins—wheat germ agglutinin, lentil lectin and concanavalin A. Platelets stored at either temperature for different times showed increased sensitivity to lectins. Lectins which were nonagglutinating to fresh platelets readily agglutinated stored platelets. The platelets stored for 24 h or longer lost their ability to respond to thrombin but demonstrated enhanced aggregation with wheat germ agglutinin. Surface labelling experiments revealed progressive loss of a glycoprotein of Mr 150 000 (GPIb) together with the appearance of components with Mr 69 000, 60 000 and 25 000 respectively. New high molecular weight glycoproteins were detected only in stored platelets. These findings illustrate the usefulness of lectins for the detection of altered expression of surface glycoconjugates which may be a factor in storage related dysfunction of platelets.