bluuebunny/crossref_metadata_2025 huggingface dataset:
Bone Marrow Transplantation in Fanconi Anaemia
Authors: Gluckman E. , Devergie A. , Schaison G. , Bussel A. , Berger R. , Sohier J. , Bernard J.
Published: March 2008

Summary Five patients with Fanconi anaemia have been treated by bone marrow transplantation from HLA identical donors. Only one patient survived for more than 3 years. She is now perfectly healthy with complete haematological reconstitution with chimaerism and disparition of chromosomal abnormalities. In contrast, four patients died of acute severe GVHD soon after grafting. In addition, all had signs of severe cyclophosphamide toxicity. This evolution could be explained by a special sensitivity of FA cells to alkylating agents and may indicate the need to modify the conditioning regimen in FA patients.
Plasma Erythropoietin Levels in Mice during the Growth Period
Authors: Meberg A. , Hågå P. , Johansen M.
Published: March 2008

Summary Plasma erythropoietin (erythropoiesis stimulating factor(s), ESF), PCV and body weight were measured in normal mice from birth until the age of 70 d. Low but detectable ESF activity was present at birth, followed by undetectable levels 12–48 h after birth. Thereafter the ESF level rapidly increased. Peak levels were obtained 15–20 d after birth. During the same phase an increased growth velocity occurred, coincident with decreased PCV levels. A fall to undetectable levels in plasma ESF activity coincided with decelleration of growth 40–50 d after birth. In small litters (four pups per litter) growth velocity and PCV levels were significantly higher than in large litters (16 pups per litter) 8 and 15 d after birth. The plasma ESF activity, however, did not differ between the two groups. Prohibiting suckling for a period of 16 h did not change the plasma ESF level. The hypothesis is put forward that growth directly or indirectly stimulates ESF production.
The Regulation of Iron Release from the Perfused Rat Liver
Authors: Baker E. , Morton A. G. , Tavill A. S.
Published: March 2008

SummaryFactors affecting iron efflux from the isolated perfused rat liver were studied following the intravenous administration of transferrin‐59Fe or transferrin‐55Fc administered to the rat from 1·5 h to 3·5 d before perfusion of the liver.

The liver was perfused with rat red cells suspended either in rat plasma or Eagle's Basal Medium (EBM). The mean rate of efflux into a plasma pool containing normal iron and transferrin concentrations was 0·9% of the initial hepatic radioactive iron pool per hour. In EBM the average rate of efflux was 0·1%/h and this could be increased to the rate observed with plasma by the addition of apotransferrin. The rate of iron release from the liver in the presence of apotransferrin or other chelators was inversely proportional to the time of prelabelling. Maximal release rates were observed in livers perfused within 5 h of administering transferrin‐59Fe to the rat. The effect of apotransferrin on efflux into EBM was concentration dependent. However, the maximum release of liver iron by apotransferrin occurred at physiological apotransferrin concentrations and addition of apotransferrin to plasma produced no increase in the rate of iron efflux. The stimulation of iron release in EBM caused by apotransferrin could be reversed by reducing the unsaturated iron binding capacity of the perfusate, either by addition of iron or removal of apotransferrin. However, increasing the iron concentration in the perfusate by the addition of iron‐saturated transferrin without any reduction in the unsaturated iron binding capacity additionally increased iron release into plasma and EBM. This presumably reflects the exchange of plasma transferrin‐36Fe for liver59Fe. Hence iron release measured in these studies represents the sum of two processes—net release of59Fe induced by apotransferrin and iron exchange between plasma and liver iron pools.

Apotransferrin and desferrioxamine were equally effective, per unit iron binding capacity, in mobilizing liver iron, and may compete for the same parenchymal iron pool. This suggests that mobilization of iron by apotransferrin may depend solely onits ability to chelate ferric iron and not on a more specific ferroxidase activity or interaction with membrane receptors.
An Electrophoretic and Quantitative Analysis of Coagulation Factor XIII in Normal and Deficient Subjects
Authors: Board P. G. , Coggan M. , Hamer J. W.
Published: March 2008

Summary Previous electrophoretic studies of the A and B subunits of factor XIII have revealed considerable genetic heterogeneity. The present work investigates the electrophoretic forms and quantitates the A and B subunits in a family with inherited factor XIII deficiency. The data indicate that the deficiency in this family is due to a null allele at the locus controlling the A subunit. All family members were found to have decreased levels of B subunit. The data also indicate that there is no difference in thrombin activated transamidase activity between normal individuals with the three commonly occurring electrophoretic phenotypes of the A subunit.
Coagulation Factors in the Human Fetus of about 20 Weeks of Gestational Age
Authors: Terwiel Jack Ph. , Veltkamp Jan J. , Bertina Rogier M. , Muller Hein P.
Published: March 2008

Summary In plasma samples of 11 fetuses of about 20 weeks of gestational age the following coagulation factors have been determined (mean values found are given in parentheses): fibrinogen (0·30 U/ml), prothrombin (±0·17 U/ml), factor V (0·28 U/ml), factor VII (0·21 U/ml), factor VIII coagulant activity (factor VIII:C) (0·12 U/ml), factor VIII‐related antigen (factor VIIIR:Ag) (1·04 U/ml), coagulant factor VIII‐related antigen (factor VIII:CAg) (0·19 U/ml), factor IX coagulant activity (0·05 U/ml), factor IX antigen (≤0·03 U/ml), factor X (0·19 U/ml) and antithrombin III (AT‐III) (0·23 U/ml).

Our data support the evidence that prenatal diagnosis of haemophilia A is at present possible; less optimism is warranted where haemophilia B is concerned. The number of samples is sufficient to establish normal values for the age group.

Means of quality control of the sample—which is often difficult to obtain—are discussed.
Iron Release from Isolated Hepatocytes
Authors: Baker E. , Vicary F. R. , Huehns E. R.
Published: March 2008

Summary.The isolated hepatocyte suspension was evaluated as an experimental procedure for investigating liver iron metabolism. Following prelabellingin vivowith transferrin‐59Fe, isolated hepatocytes released radioactive ironin vitroby a temperature dependent process, without change in cell viability. Iron mobilization was increased by serum, apotransferrin and a range of iron chelators, of which the most effective were citrate, desferrioxamine and the ionophore A 23187. The rate of iron release was inversely related to oxygen levels, indicating that a ferric—ferrous reduction was involved in iron mobilization. The uncoupler TTFB, DTPA, and hypercapnia caused a reduction in iron release, but the metabolites cysteine, NADH and ascorbic acid had no effect. It was concluded that isolated hepatocytes are a useful experimental model for studying iron metabolism and for further evaluation of iron chelators.
Liposome‐encapsulated Desferrioxamine in Experimental Iron Overload
Authors: Lau E. H. , Cerny E. A. , Rahman Y. E.
Published: March 2008

Summary. We have encapsulated desferrioxamine (DF) in multilamellar liposomes (ML) and unilamellar liposomes (UL). Liposomes were prepared either with or without a glycolipid, i.e. galactocerebroside (GC). The average diameter of ML was 0.5 μm, and that of UL was 0.08 μm. Less than 5% of DF leaked out from the liposomes after incubation in mouse plasma for 6 h. 59Fe‐ferritin and 59Fe‐labelled heat damaged erythrocytes (59Fe‐DRBC) were administered to normal and hyper‐ transfused mice as models of iron overload. Ferritin was used to label liver parenchymal cells and DRBC to label the Kupffer cells of the liver. A single injection of ML or UL with or without galactocerebroside into normal and hypertransfused mice enhanced from 3‐ to 15‐fold the urinary excretion of radioiron from 59Fe‐ferritin and from 59Fe‐DRBC injected mice. For both the normal and hypertransfused mice, liposomes containing GC removed more 59Fe radioactivity from 59Fe‐ferritin injected mice than liposomes without the glycolipid; whereas liposomes without GC removed more 59Fe radioactivity from mice receiving 59Fe‐DRBC. Thus GC‐liposomes may have a higher affinity for parenchymal cells of the liver, whereas liposomes without the glycolipid may have a higher uptake by the Kupffer cells.
Prognostic Significance of Bone‐Marrow Patterns in Chronic Lymphocytic Leukaemia
Authors: Rozman C. , Hernandez‐Nieto L. , Montserrat E. , Brugues R.
Published: March 2008

Summary. Bone‐marrow biopsy has been performed in 63 cases of chronic lymphocytic leukaemia (CLL). Four different histological patterns were observed: (a) interstitial (lymphoid infiltration without displacement of fat cells) in 12 cases; (b) nodular (abnormal lymphoid nodules without interstitial infiltration) in 10 cases; (c) mixed (combination of the first two patterns) in 21 cases; and (d) diffuse (replacement of both haemopoietic and fat cells by lymphoid infiltration) in 20 cases.

Statistical analysis of actuarial curves showed a significant difference of survival probability according to the bone marrow infiltration patterns. Thus, in patients with interstitial or nodular patterns the life expectancy is significantly longer than in those with mixed or diffuse patterns. Furthermore, a significant degree of correlation between bone marrow infiltration patterns and different methods of clinical staging in CLL was apparent.

The different bone marrow infiltration patterns in CLL probably reflects variations in the amount of lymphoid accumulation during the natural course of this disease. Because of its prognostic significance, bone marrow biopsy should have a place in CLL evaluation and staging.
Distribution of 250 Cases of Acute Myeloid Leukaemia (AML) according to the FAB Classification and Response to Therapy
Authors: Sultan C. , Deregnaucourt J. , Ko Y. W. , Imbert M. , Ricard D'Agay M. F. , Gouault‐Heilmann M. , Brun B.
Published: March 2008

Summary. 250 consecutive cases of AML in adults were diagnosed over a 6 year period in the same institution. Pretreatment blood and bone marrow smears and also cytochemical markers were taken into account in the study. All cases were reviewed by three different observers and classified according to the FAB criteria. The final diagnosis resulted from agreement of at least two observers. Some discrepancies occurred in the classification and are discussed. The prognostic implication of AML subclassification was assessed as the percentage of complete remission in 100 cases.
Newborn Factor VIII Complex: Elevated Activities in Term Infants and Alterations in Electrophoretic Mobility Related to Illness and Activated Coagulatio
Authors: Johnson Scott S. , Montgomery Robert R. , Hathaway Wm. E.
Published: March 2008

Summary. The factor VIII coagulant activity (FVIII :C), factor VIII related antigen (FVIII: RAG), and factor VIII ristocetin cofactor activity (FVIII :RCF) was determined in the cord blood samples of 30 healthy term newborns. Sodium citrate anticoagulant, cold, and a proteolytic inhibitor were used in sample processing. All three factor VIII activities were elevated in infants compared to adults; additionally, FVIII: RAG was significantly higher in vaginally compared with caesarean section delivered infants. Crossed immunoelectrophoresis of the term infant plasma showed a consistently normal factor VIII mobility. An additional group of 22 sick premature and term infants had determinations of factor VIII antigen and crossed immunoelectrophoresis. The FVIII: RAG of sick infants was approximately twice that of the well term infants. Infants with severe lung disease, asphyxia, thrombosis and sepsis had normal electrophoretic mobility despite marked elevations in FVIII: RAG. Abnormal, symmetrical, more anodal migrations were seen only in a group of severely ill newborns with dessiminated intravascular coagulation (DIC) or signs of activated fibrinolysis. These results suggest that the elevated FVIII activities seen in well infants and most sick newborns are the result of increased release of a normal form of the FVIII molecule. Those elevations seen in sick newborns with DIC result from increased release and the production of an altered, faster moving FVIII molecule.
Immunologically Defined Subclasses of Acute Lymphoblastic Leukaemia in Children: their Relationship to Presentation Features and Prognosis
Authors: Greaves Melvyn F. , Janossy George , Peto Julian , Kay Humphrey
Published: March 2008

Summary. Leukaemic cells from 542 patients under 21 years of age with a diagnosis of acute lymphoblastic leukaemia (ALL) were typed with immunological cell surface markers between June 1975 and December 1979; 379 of these patients entered into the trials up until December 1978 have been followed for more than 1 year. They were divided into four subgroups: common (c) ALL, T (thymic) ALL, ‘null’ (or ‘unclassified’) ALL and a rare lymphoma/leukaemia type B‐ALL. A T‐cell phenotype was found more frequently in boys and was usually but not invariably associated with a high white cell count at presentation. A mediastinal thymic mass was present in 53% of T‐ALL patients but was not observed in any unequivocal non‐T ALL. Clinical prognosis differed substantially between the three major phenotypic classes, remission induction rate and remission duration being lowest in T‐ALL, better in ‘null’ ALL, and highest in cALL (P trend < 0·0001; P=0·0002 for comparison of cALL versus T‐ALL). There was a much higher incidence of CNS involvement in the T‐ALL group than in the cALL group or ‘null’ ALL group and although this was strongly correlated with WBC count it was also significantly associated with T‐ALL independent of WBC count.

Overall in this series and also within the major cALL subclass there is a strong correlation between high WBC count and poor clinical response (remission induction and duration). When the three major immunological subclasses are adjusted for WBC count the prognostic correlation of antigenic phenotype is reduced and statistically insignificant.

It is suggested that immunological (and enzymatic) phenotype of ALL subclasses may not be an independent correlate of prognosis but nevertheless is linked to other cell differentiation features, especially growth rate and sites of clonal expansion (e.g. marrow versus thymus), which critically influence the size of the clonogenic
Collagen Heterogeneity in Normal Human Bone Marrow
Authors: Bentley S. A. , Alabaster O. , Foidart J. M.
Published: March 2008

Summary. Paraffin embedded sections of formalin fixed, decalcified, normal, human, vertebral bone were stained immunohistochemically for collagen types I, III and IV using the peroxidase—anti‐peroxidase (PAP) technique. Preparations stained for collagen types I and III were virtually identical in appearance. These substrates were localized to the cytoplasm and fibrillar processes of a population of cells which were sparsely distributed within the haemopoietic compartment of the bone marrow, being particularly prominent in relation to the marrow sinusoids and fat spaces. They would thus appear to parallel the known distribution of reticulum cells, although their morphology differed in some respects from classical descriptions of the latter cell type.

Type IV collagen was found in association with the endothelial lining of the sinusoids. Other connective tissue elements (bone, periosteum, endosteum, blood vessels, etc.) showed characteristic collagen heterogeneity.

These results indicate that collagen is a significant component of the bone marrow connective tissue.
G6PD Napoli and Ferrara II: Two New Glucose‐6‐Phosphate Dehydrogenase Variants having Similar Characteristics but Different Intracellular Lability and Specific Activity
Authors: Flora A. De , Morelli A. , Benatti U. , Giuntini P. , Ferraris A. M. , Galiano S. , Ravazzolo R. , Gaetani G. F.
Published: March 2008

Summary. Two new glucose‐6‐phosphate dehydrogenase (G6PD, d‐glucose 6‐phosphate: NADP oxido reductase, E.C. 1.1.1.49) variants, designated G6PD Napoli and G6PD Ferrara II, are described in propositi from two unrelated families. Characterization side by side of the two variants according to W.H.O. recommendations reveals minor differences which are mostly related to utilization of artificial substrates (increased in both cases as compared with normal G6PD type B). Other properties, which are not significantly distinctive between the two variants, are an enzyme activity amounting to nearly 20% of normal, a decreased electrophoretic mobility, decreased Km values for glucose‐6‐phosphate and NADP, normal thermostability and biphasic pH curves. However, marked differences emerged between the two variants and between either variant and G6PD B as well, when a number of microtechniques were used. These were: (1) the half‐lives of G6PD Napoli and G6PD Ferrara II are 16 and 29 d, respectively, while that of G6PD B is 63 d; (2) the specific activities, measured by a method involving direct estimation of G6PD protein on sodium dodecyl sulphate polyacrylamide gel electrophoretic tracings, are 166 I.U./mg (G6PD Napoli) and 59 I.U./mg (G6PD Ferrara II), as compared with normal value of 180 I.U./mg (G6PD B). On the whole, these findings allow the conclusion that the deficiency of catalytic activity is related to an accelerated though distinctive decay of both mutant enzyme proteins within the affected erythrocytes and that a significant impairment of catalytic efficiency is also involved, as a result of the underlying structural mutation in the case of G6PD Ferrara II.
Ineffective Erythropoiesis in Haemoglobin Eβ ‐thalassaemia: an Electron Microscope Study
Authors: Wickramasinghe S. N. , Hughes Madeleine , Wasi Prawase , Fucharoen Suthat , Modell Berandette
Published: March 2008

Summary. Electron microscope studies have been performed on the bone marrow cells of two non‐splenectomized patients and the circulating erythroblasts and reticulocytes of three splenectomized patients with HbE/β‐thalassaemia. Some intracellular precipitates (probably consisting of α‐chains) and mild dyserythropoietic changes were found in the early polychromatic erythroblasts within the bone marrow. Larger quantities of precipitate and more marked dyserythropoietic changes were found in the late polychromatic erythroblasts and reticulocytes both within the marrow and within the circulation. The bone marrow macrophages contained phagocytosed erythroblasts within their cytoplasm. These data indicate that the anaemia in HbE/β‐thalassaemia results largely from dyserythropoiesis and ineffective erythropoiesis. The ultrastructural abnormalities encountered in the cases of HbE/β‐thalassaemia were qualitatively and quantitatively similar to those seen in homozygous β‐thalassaemia.
Changes in Energy Metabolism, Structure and Function in Alveolar Macrophages under Anaerobic Conditions
Authors: Butterick Charles J. , Williams David A. , Boxer Laurence A. , Jersild Ralph A. , Mantich Jr Nancy , Higgins Coleen , Baehner Robert L.
Published: March 2008

Summary.

To determine whether the change in energy metabolism of guinea‐pig alveolar macrophages (AM) would alter their function to resemble peritoneal macrophages (PM), AM were exposed to strict anaerobic environments for 96 h. Exposure of cultivated AM to hypoxic conditions resulted in a decreased activity of cytochrome oxidase, a key enzyme in oxidative phosphorylation, whereas pyruvate kinase activity, a key enzyme in glycolysis, increased to levels observed in PM. Under hypoxic conditions the total mitochondrial structure available for respiratory activity also decreased in the glycolytic energy‐dependent AM.

Accompanying the shift in energy metabolism, adaptive changes in the functional responses of lectin‐receptor activity occurred in the AM exposed to hypoxic conditions. Culture of AM in an anaerobic environment led to a loss in their ability to mobilize their lectin receptors in response to cytochalasin B, whereas AM maintained in an aerobic environment could mobilize their receptors in response to either cytochalasin B and D. Alterations in O2 tension affect AM metabolism, morphology and function and indicate that the AM is able to change its energy metabolism according to environmental circumstances.
Relation of Osteoclast Activating Factor Production to Extent of Bone Disease in Multiple Myeloma
Authors: Durie Brian G. M. , Salmon Sydney E. , Mundy Gregory R.
Published: March 2008

Summary. Measurements of total body myeloma cell number and osteoclast activating factor (OAF) production by bone marrow myeloma cells in vitro were made in 33 patients with plasma cell myeloma. There was a highly significant correlation (P < 0.001) between the amount of OAF produced by bone marrow myeloma cells and the extent of skeletal destruction. Serial studies indicated reduction of OAF production with remission induction and high OAF production at the time of relapse with new bone destruction. Although hypercalcaemia occurred only in patients with the most extensive bone lesions, there was no direct relationship between OAF production and the serum calcium concentration. These data suggest that measurement of OAF production in multiple myeloma may predict those patients at risk for development of extensive skeletal destruction due to this neoplasm.
Fixation of C3 to Platelets in Vitro by Antiplatelet Antibody from Patients with Immune Thrombocytopenic Purpura
Authors: McMillan R. , Martin M.
Published: March 2008

Summary. Chronic immune thrombocytopenic purpura (ITP) is due to platelet destruction by an IgG antiplatelet antibody. Recent studies by some investigators suggest in vivo fixation of C3 by the antiplatelet antibody in ITP patients; other groups have not confirmed these findings. In the present studies, purified IgG produced in vitro by splenic cells from two patients with ITP resulted in C3 fixation to target platelets. Since cell‐bound C3 increases the efficiency of cell destruction in many experimental antibody systems, the ability of the IgG antibody in patients with ITP to fix C3 may influence the severity of their disease.
Response of Factor VIII/von Willebrand Factor to DDAVP in Healthy Subjects and Patients with Haemophilia A and von Willebrand's Disease
Authors: Mannucci P. M. , Canciani M. T. , Rota L. , Donovan B. S.
Published: March 2008

Summary. These studies were designed with the purpose of providing clinico‐pharmacological information relevant to the use of DDAVP in the management of mild haemophilia and von Willebrand's disease (VWD). In healthy subjects, intravenous DDAVP produced its maximal response at a dose of 0.3 μg/kg. The extent of the increase in factor VIII coagulant activity (VIII:C) and factor VIII related antigen (VIIIR:Ag) induced by this dose was not significantly different from that observed with the same dose in haemophiliacs and VWD patients. In these, the bleeding time was not shortened. DDAVP given intranasally was followed by a two‐fold increase of VIII:C. This route of administration might be adopted to provide an emergency aid in bleeding patients and to yield higher VIII:C levels in blood donors. In healthy subjects, the half‐disappearance time of autologous VIII:C after increase induced by i.v. DDAVP is similar to that observed in patients with VWD treated in the same conditions, whereas the response appears to be more prolonged in haemophiliacs. This study shows that the consistency of the VIII:C response tends to decrease when repeated doses are given to healthy subjects. Repeatedly‐treated haemophiliacs and VWD patients showed varied patterns, ranging from no change of the response to its early abolishment.
Familial Bleeding Tendency with Partial Platelet Thromboxane Synthetase Deficiency: Reorientation of Cyclic Endoperoxide Metabolism
Authors: Defreyn G. , Machin S. J. , Carreras L. O. , Dauden M. Vergara , Chamone D. A. F. , Vermylen J.
Published: March 2008

Summary. Three family members from three successive generations presented with a moderate bleeding tendency and a functional platelet defect. They had absent aggregation with arachidonic acid (0·6–3 mM), reversible aggregation with ADP (4 μM) and cyclic endoperoxide analogues, single wave aggregation only with adrenaline (5·4 μM) and a prolonged template bleeding time (>30 min). Malondialdehyde formation was reduced after N‐ethylmaleimide stimulation (2–6 nmol/109 platelets; control values 8–12 nmol) and serum thromboxane B2 values were reduced (33–101 ng/ml; control values 200–700 ng/ml). When the platelets were incubated with [3H] arachidonic acid the final metabolite of the lipoxygenase pathway (HETE) was produced in normal amounts but the production of thromboxane B2 and HHT was decreased whereas prostaglandin F2α, E2 and probably D2 were increased. Evidence for enhanced production of prostaglandin D2 was also provided by the rise in the patient's platelet cyclic AMP levels following stimulation with arachidonic acid. The patient's washed platelets stimulated the production of 6‐keto PGF1α by aspirin‐pretreated cultured bovine endothelial cells. The plasma levels of 6‐keto PGF1α (439–703 pg/ml; normal 181 ± 46 pg/ml) were raised. The decreased production of thromboxane B2, HHT and malondialdehyde and increased formation of prostaglandin F2α, E2, D2 and of 6‐keto PGF1α are compatible with a partial platelet thromboxane synthetase deficiency and reorientation of cyclic endoperoxide metabolism. The markedly prolonged bleeding time would result not only from reduced formation of thromboxane A2 but also from increased production of the aggregation inhibiting prostaglandins PGI2 and PGD2.
The Role of Synovectomy in the Management of Recurrent Haemarthroses in Haemophilia
Authors: Kay Lesley , Stainsby David , Buzzard Brenda , Fearns Maureen , Hamilton P. J. , Owen Philip , Jones Peter
Published: March 2008

Summary. Between August 1973 and May 1979, 18 patients suffering from severe haemophilia A underwent synovectomy for recurrent haemarthroses, resistant to medical management. A total of 23 joints (11 knees and 12 elbows) were subjected to operation, five patients undergoing two synovectomies on different joints. Post‐operative follow‐up period ranged from 12 to 58 months for elbow synovectomy and from 29 to 76 months for knee synovectomy. All patients experienced fewer haemarthroses, the average number of bleeding episodes per joint over a 12 month period being reduced from 19 to 3 for knee joints, and from 24 to 3 for elbow joints. This improvement was apparent in the immediate post‐operative year and maintained thereafter. Over the same follow‐up period nine of the 11 knee joints were found to have lost an average 42° mobility. Following elbow synovectomy five out of 12 patients lost an average of 28° mobility; six patients gained an average 11° mobility.

The post‐operative complication rate was high for knee synovectomy, 54% suffering haemorrhage despite haemostatic factor VIII levels. For elbow synovectomy the rate was much lower, 75% of operations being uncomplicated. The average in‐patient time for knee operation was 75 d, and for the elbow 19 d.

We conclude that synovectomy of the knee joint is to be avoided when other means of reducing bleeding episodes are available, whereas elbow synovectomy retains a useful role in the treatment of recurrent haemarthroses which do not respond to clotting factor prophylaxis.
Alterations of Factor VIII von Willebrand Factor in Clinical Conditions Associated with an Increase in its Plasma Concentration
Authors: Lombardi R. , Mannucci P. M. , Seghatchian M. J. , Garcia V. Vicente , Coppola R.
Published: March 2008

Summary. Factor VIII‐related antigen (VIIIR: Ag) was consistently higher than factor‐VIII procoagulant activity (VIII:C) in 57 patients with clinical conditions characterized by acute‐phase reactions. Two different methods for measuring VIII:C (one‐ and two‐stage assays) and VIIIR: Ag (electroimmunodiffusion and immunoradiometric assay) gave concordant results in the majority of cases. In 43% of plasma samples, crossed immunoelectrophoresis in agarose gel was characterized by the appearance of an additional, fast‐moving precipitin peak which was immunologically identical with the major, slower‐moving VIIIR : Ag peak. The fast‐moving peak was detected in all the patients with clinical conditions typically associated with increased plasma proteolysis (DIC, acute pancreatitis, during thrombolytic therapy). It was present in a smaller proportion of cases with liver and renal failure and malignancies and in the post‐operative period. The additional VIIIR : Ag peak is thought to be the result of in vivo factor VIII/von Willebrand factor fragmentation by proteolytic enzymes.
Erythrocyte Deformability in Sickle‐Cell Crisis
Authors: Kenny M. W. , Meakin M. , Worthington D. J. , Stuart J.
Published: March 2008

Summary. A serial study of erythrocyte deformability, plasma viscosity, and whole‐blood viscosity has been made during 10 sickle‐cell vaso‐occlusive crises. The peak serum lactate dehydrogenase level was used to confirm the duration of crisis and the rheological changes were compared with 19 estimations made on the same patients when asymptomatic. Erythrocyte deformability, measured by filtration of washed erythrocytes through polycarbonate filters of 5 μm pore size, was significantly reduced on day 1 of crisis and, in one additional patient, this occurred 24 h before the onset of pain. There was no increase in irreversibly‐sickled‐cell counts and plasma‐ and blood‐viscosity did not increase significantly until day 5 of crisis, in parallel with the acute‐phase rise in plasma fibrinogen. Measurement of erythrocyte filterability is therefore a valuable technique for investigating the pathogenesis of the early stages of sickle‐cell crisis.
Genetic Relationship between Fetal Hb Levels in Normal and Erythropoietically Stressed Baboons
Authors: DeSimone Joseph , Heller Paul , Biel Merrill , Zwiers David
Published: March 2008

Summary. Previous studies have shown that the magnitude of the fetal haemoglobin (Hb F) response to haemolytic anaemia and hypobaric hypoxia in the baboon is specific to an animal (‘high and low Hb F responders’), suggesting that the Hb F response is under genetic control. In this study Hb F levels in 55 adult (over 8 years old) and 23 juvenile unstressed baboons varied between 0·02% and 0·6% (‘resting Hb F levels’). Twenty‐nine of these animals were subjected to haemolytic stress and the magnitude of their Hb F response was positively correlated with the resting Hb F levels. In addition, the resting levels of Hb F in parents were positively correlated with those of their offspring. In 11 animals, seven adults and four juveniles, subjected to haemopoietic stress the Hb F levels were increased proportionally to the number of F‐cells. In juvenile animals the calculated concentration of Hb F per F‐cell was markedly higher than in adult animals. These data demonstrate that the resting level of Hb F is predictive of the magnitude of the Hb F response to stress erythropoiesis. The number of F‐cells and the concentration of Hb F per cell in erythropoietic stress appear to be modulated by different mechanisms.
The Mechanisms which Produce Vacuolated and Degranulated Eosinophils
Authors: Tai P.‐C. , Spry C. J. F.
Published: March 2008

Summary. As blood eosinophils in patients with an eosinophilia may contain refractile‘vacuoles’(vacuolated eosinophils), and some cells contain only a few granules (degranulated eosinophils) which show ultrastructural changes, experiments were done to see whether similar morphological alterations could be induced in blood eosinophils from normal people. Overnight culture of normal eosinophils with serum treated with cobra venom factor induced refractile‘vacuoles’and ultrastructural changes in granule matrix material. On the other hand, concanavalin A, 10 μ/ml for 2 h, led to the formation of larger perinuclear vacuoles containing granule contents, and ultrastructural changes were more marked in granule crystalloid material. Cytochalasin B inhibited these effects of concanavalin A. Neither of these stimuli caused a marked reduction in the number of cytoplasmic granules, but lysolecithin and insoluble (but not soluble) immune complexes produced large endocytic vacuoles into which partially solubilized and whole eosinophil granules were discharged.

These results suggest that eosinophil granules can be affected in two distinct ways. In one, the granule matrix is altered leading to the light microscopy appearances of small refractile ‘vacuoles’. In the second, the crystalloid material is dispersed into the matrix. These apparently distinct steps precede the release of the granule contents into large cytoplasmic spaces or to the outside of the cell. Also, as patients' eosinophils may show one or both of these alterations it is suggested that they are distinct events. As concanavalin A induced solubilization of granules did not result in release to the outside, it is also proposed that an additional stimulus may be required to produce exocytosis of eosinophil granule contents. Further studies may show how these processes are linked, and their relative importance in eosinophil effector functions.
Sensitivity of Acute Myeloid Leukaemia Cells to Colony Stimulating Activity: Relation to Response to Chemotherapy
Authors: Francis G. E. , Tuma G. A. , Berney J. J. , Hoffbrand A. V.
Published: March 2008

Summary. Agar cultures of acute myeloid leukaemia (AML) cells were used to determine the sensitivity of AML clone forming cells to the specific regulator granulocyte‐macrophage colony stimulating activity (CSA). The mean CSA threshold (amount of CSA required to stimulate 0.5 of the clone forming cells) of 27 different AML cell samples varied from normal to an approximately nine‐fold increase in CSA requirement. The degree of sensitivity to CSA at presentation was found to be closely correlated to the response to induction chemotherapy in 15 patients. There was a highly significant correlation (P<0.001) between the mean CSA threshold and the number of courses of chemotherapy required to induce remission. Also, an increased mean CSA threshold at presentation was associated with a significantly slower decline of marrow blasts following the first course of chemotherapy and a reduced remission rate. Sensitivity to CSA was closely related to the clone size achieved in maximally stimulated cultures of AML cells and this in turn also related to the remission rate and ease with which remission was achieved (presentation marrows, 39 patients). Possible reasons for the linking of these two functional properties of AML cells and their relation to response to chemotherapy will be discussed.
Circulating Immune Complexes in Human Acute Leukaemia
Authors: Balestrieri G. , Tincani Angela , Cattaneo R. , Rossi G. , Verzura Paola , Marini G. , Calculli G. , Ferremi P. , Marinone G.
Published: March 2008

Summary. Circulating immune complexes (CIC) in the sera of 60 newly diagnosed leukaemic patients were investigated by two methods, 125I‐C1q binding test (C1q‐BA) and conglutinin binding assay (KgB‐SP). Positivity percentages were respectively 20.0% (C1q‐BA) and 28.3% (KgB‐SP). The small overlap between the results of the two methods suggests the occurrence of different types of CIC. The presence of CIC was found to be related only to clinical haemorrhage and thrombocytopenia; it did not prove to affect the prognosis and the survival of leukaemic patients.
Relationship of Raised Platelet IgG in Thrombocytopenia to Total Platelet Protein Content
Authors: Pfueller Sharron L. , Cosgrove Leah , Firkin Barry G. , Tew Deborah
Published: March 2008

Summary. Platelet‐associated IgG (PA IgG) of washed platelets of 20 normal controls and 45 thrombocytopenic patients was measured by radioimmunoassay and related to total platelet protein content.

Mean values (±2 SD) for 20 normals were 4.4 ± 3.5 fg IgG per platelet (fg IgG/pl), 2.1 ± 1.0 pg protein per platelet (pg protein/pl) and a ratio of IgG per g platelet protein of 2.1 ± 1.8 mg IgG/g protein. Patients could be divided into two groups: Group I (31) with normal IgG/g protein ratios and either normal (16) or raised (15) fg IgG/pl, and Group II (14) with both fg IgG/pl and IgG/g protein raised. Of the 21 patients with idiopathic thrombocytopenia (ITP), 13 were in Group I (seven with raised and six with normal fg IgG/pl), and eight in Group II. There was significant correlation between PA IgG (fg IgG/pl) and platelet protein for the entire Group I (r=0.95, P < 0.001). The ITP patients in this group showed a similar correlation (r=0.77, P < 0.001), suggesting that raised PA IgG levels in Group I patients may be a result of protein‐rich platelets.

60‐90% of PA IgG was found in the soluble fraction of lysates of platelets from both normals and patients. Thus, it is either non‐specifically associated with platelets or is antibody directed towards easily solubilized platelet antigens. Nine thrombocytopenic patients without immune disorders had raised PA IgG. These results question the assumption that raised PA IgG always indicates specific antiplatelet antibody.
Depressed Responsiveness to Adrenaline in Platelets from Apparently Normal Human Donors: a Familial Trait
Authors: Scrutton M. C. , Clare K. A. , Hutton R. A. , Bruckdorfer K. R.
Published: March 2008

Summary. Decreased responsiveness to adrenaline has been observed in five apparently normal unrelated human donors. In four of the donors this trait is inherited. Three of the donors, as well as their affected relatives, also exhibit depressed responsiveness to collagen and vasopressin but normal responsiveness to ADP and thrombin. The other two affected donors exhibit normal responsiveness to most other agonists.

Normal responsiveness can be restored in all instances either by incubating the platelet‐rich plasma at 20°C or by addition of a low concentration of the divalent cation ionophore, A‐23187. All affected platelets which have been examined have ATP and ADP contents, cholesterol to phospholipid ratios, and phospholipid class compositions within the normal range. Both the resting level of cyclic‐3′,5′‐AMP and the ability of adrenaline to prevent elevation of cyclic‐3′.5′‐AMP levels by prostaglandin E1 are normal. Mixing experiments demonstrate the absence of a circulating inhibitor of platelet function and suggest that the defect resides in the platelets. We conclude that the depressed responsiveness of human platelets to adrenaline may result from a defect in Ca2+ mobilization to the cytosol.
Dynamics of Red Cell Egress from Bone Marrow after Blood Letting
Authors: Aoki Makoto , Tavassoli Mehdi
Published: March 2008

Summary. To study the dynamics of red cell egress from the marrow, the demand for red cell delivery was enhanced in splenectomized rats by removing 25% of the blood volume, which was then immediately replaced by plasma. Within 15 min, packed cell volume declined by 22% of the initial value. Corrected reticulocyte count followed a biphasic pattern: an initial peak amounting to 26% occurred within 4‐6 h followed by a more marked peak after 48 h. Quantitative electron microscopy of the marrow sinus wall indicated significant increases in the numbers of reticulocytes and leucocytes in transit after 5 h. Vesicles containing a flocculant substance were seen in the endothelium. The vesicles could cause segmental destabilization of endothelium, providing suitable areas for cell migration. There was also a significant reduction in the mean length of the overlapping segments of the endothelial cells, suggesting that these cells slid over one another to increase the luminal calibre. Within the rigid confines of bones where the marrow volume is fixed, this increase may lead to the displacement of mature haemopoietic cells into the lumen and whence into the circulation.
Platelet Adherence to Collagen: Role of Prostaglandin—Thromboxane Synthesis
Authors: Cowan Dale H.
Published: March 2008

Summary. The effect of aspirin and indomethacin on adherence of human platelets to collagen was assessed by affinity chromatography on collagen/Sepharose. Studies were done using platelets from normal subjects and subjects ingesting aspirin. Blood was anticoagulated with EDTA, EGTA or citrate, and platelets were suspended in plasma or buffer after separation by centrifugation or gel filtration. The adherence to collagen of platelets from subjects ingesting 1200 mg aspirin per day decreased significantly (P<0.05 or below). A significant reduction in adherence also occurred after exposure to aspirin and indomethacin in vitro. The reduction in adherence was associated with inhibition of malondialdehyde (MDA) production and was unaffected by the presence of CP/CPK. Exposure of platelets to aspirin at 24° caused no impairment of adherence. The addition of 1.0 mM Ca++, 0.5 or 1.0 mM Mg++, or 1 mM arachidonic acid significantly diminished the inhibition of adherence by aspirin. Imidiazole had an effect on adherence opposite to that of aspirin. Changes in release of 14C‐serotonin in general paralleled changes in adherence. The data suggest that aspirin and indomethacin impair but do not fully inhibit platelet adherence to collagen. Factors affecting this inhibitory activity in our system are the presence of plasma and availability of divalent cation. Platelet—collagen adhesion appears partly dependent upon prostaglandin–throm‐boxane synthesis and may be promoted by a different pathway that is stimulated by divalent cations and unaffected by inhibition of prostaglandin synthesis.
Mepacrine Stains the Dense Bodies of Human Platelets and not Platelet Lysosomes
Authors: Skaer R. J. , Flemans R. J. , McQUILKAN S.
Published: March 2008

Summary. Mepacrine, used as a vital stain, accumulates in the lysosomes of most cells. In platelets, however, it does not stain the lysosomes but is a specific marker for dense bodies.
Monoclonal Antibody to Human Platelet Glycoprotein I I. IMMUNOLOGICAL STUDIES
Authors: McMichael A. J. , Rust N. A. , Pilch J. R. , Sochynsky R. , Morton J. , Mason D. Y. , Ruan C. , Tobelem G. , Caen J.
Published: March 2008

Summary. A monoclonal hybridoma antibody specific for platelet glycoprotein I complex is described. The nature of the antigen was determined by demonstration that it was chymotrypsin sensitive and gave a peak at 150000 daltons on SDS‐PAGE after immunoprecipitation. The expression of the antigen is restricted to platelets and megakaryocytes with at least 1.6 × 104 molecules of antigen per platelet. The antibody failed to bind to platelets from patients with Bernard Soulier syndrome, where there is known to be a deficiency of glycoprotein Ib/Is expression. Binding to platelets from patients with Glanzmann's thrombasthenia was normal.
Binding of Low‐Molecular‐Weight Canine Factor VIII Coagulant from von Willebrand Plasma to Canine Factor VIII‐Related Antigen
Authors: Benson Roger E. , Johnson Gary S. , Dodds W. Jean
Published: March 2008

Summary. Plasmas having no detectable factor VIII‐related antigen but moderate factor VIII coagulant were obtained from two unrelated dogs homozygous for von Willebrand's disease and with the severe clinical expression of the disease. When these plasmas were gel‐filtered in a buffer at physiologic ionic strength, the factor VIII coagulant eluted in the bed volume as a single well‐defined peak. Addition of protease inhibitors, including diisopropylfluorophosphate, did not change the elution pattern. Each plasma was then combined individually with plasmas from six different mutants of canine haemophilia, all of which had normal factor VIII‐related antigen but no detectable factor VIII coagulant. The factor VIII coagulant elution profile of these combined plasma resembled that of normal canine plasma. Slightly over half of the recovered factor VIII coagulant coeluted in the void volume with the factor VIII‐related antigen; the rest eluted as a second, distinct peak of lower molecular weight. These results demonstrated that part of the factor VIII coagulant of the von Willebrand plasmas had bound to the factor VIII‐related antigen of the haemophilic plasmas. This finding supports the theory that factor VIII exists as a macromolecular complex of nonidentical components in normal citrated plasma.
An Examination of the Labelling of Intact Human Erythrocytes with 99mTc
Authors: Thompson Stephen , Newman Peter , Maddy Alun H.
Published: March 2008

Summary. 99mTc radiopharmaceuticals are now in common use in diagnostic nuclear medicine although rather little is known about the chemical structure of the Tc‐ligand complexes formed when Tc is bound to organic compounds. We examine 99mTc‐labelled erythrocytes and find that proteins in addition to haemoglobin are labelled with 99mTc, possibly through their sulphydryl groups. This contrasts markedly to the labelling of erythrocytes with 51Cr where only haemoglobin is labelled.
Analysis of Heat‐damaged Erythrocyte Clearance Curves
Authors: Peters A. M. , Ryan P. F. J. , Klonizakis I. , Elkon K. B. , Lewis S. M. , Hughes G. R. V.
Published: March 2008

Summary. The rate of clearance from the blood of heat‐damaged erythrocytes (HDE) is used routinely as a quantitative assessment of splenic function. The time taken for the value at 3 min to fall by 50% (t0‐5) is usually taken as the index of function. The clearance of HDE is dependent on three processes: splenic blood flow, splenic HDE extraction ratio and intrasplenic transit time of ‘unextracted’HDE, returning to the circulation. Exponential analysis of the clearance curve can resolve these three functions. Simple methods of analysis, however, such ast0‐5, which are applied directly to the curve, may be weighted in favour of any one of them. In this paper, a large number of clearance curves have been analysed and the components of splenic function resolved. Thet0‐5, the percentage fall in HDE between 8 and 28 min (C20), the rate constant at 8 min (K8) and the rate constant of the tail of the curve (α2) have been correlated with these components.K8showed a close correlation with splenic blood flow, and α2with the rate of HDE phagocytosis. In general, the correlation between the various components of splenic function was better withC20than witht0‐5. This is explained predominantly by the fact that thet0‐5includes liver clearance. Thet0‐5should therefore be used with caution as an estimate of splenic function, which can be usefully assessed by applying alternative simple methods of analysis described.
Measurement of Red Cell Volume and Splenic Red Cell Pool using 113mIndium
Authors: Radia R. , Peters A. M. , Deenmamode M. , Fitzpatrick M. L. , Lewis S. M.
Published: March 2008

Summary. Using the lipophilic chelating agent, acetylacetone, red cells have been radiolabelled with the short‐lived, generator‐produced isotope, 113mIn. Following re‐injection of these labelled cells, red cell volume has been measured and compared with corresponding values using 99mTc labelled red cells in 18 patients, and with 51Cr labelled red cells in five patients. 99mTc slightly overestimated red cell volume in relation to 113mIn, but 51Cr values were identical to 113mIn values. There was a close correlation between splenic red cell pool measured with 99mTc and with 113mIn. It was concluded that the intracellular stability and gamma emission of 113mIn make this isotope a superior alternative to 99mTc and 51Cr in measurements of red cell volume and splenic red cell pool.