Platelet Heterogeneity: Biology and Pathology

ISBN-13: 9781447117650 / Angielski / Miękka / 2011 / 270 str.

John Martin; Anthony Trowbridge

Opis

Battle is a practical and sometimes lasting way of solving man's problems. It relies on the strength of the combatants and ignores the truth of the dispute. Discussion face to face can dissolve attitudes which have incorrectly determined judgements. The most striking example of this that I know is a Battle in Ireland in the eleventh century, where the king of Leinster fought a Viking prince. The Icelanders had raided Ireland for several generations in search of women, which they lacked since most of the population of Iceland were men who had arrived there by rowing long-boats from Norway. The prince was leading such a raid for the first time. Standing in the prow of the leading boat he saw Irish cavalry galloping along the beach to meet them. As they approached the shore the Irish king rode out of the band to challenge single combat. The Icelander jumped into the surf to meet him. As they raised their swords each realized that the other's face was like his own. When the Irish king spoke the other recognized the language. It had been spoken in Iceland by his grandmother who had been captured and taken there from Ireland. Swords were dropped and replaced by drinking horns. It was soon established that they were cousins. The battle gave way to a life-time of close co-operation.

Spis treści

1 Platelet Density, Heterogeneity and Platelet Ageing.- Experimental Models Used to Examine the Significance of Platelet Heterogeneity.- Potential Problems Associated with Various Experimental Models.- Ultrastructural Studies and Platelet Heterogeneity.- Density-Dependent Platelet Properties and Platelet Heterogeneity.- Kinetic Models to Examine the Relationship Between Platelet Density and Age.- Is Heterogeneity of Density-Dependent Platelet Properties Significant?.- Contributions of Events During Thrombopoiesis to Platelet Heterogeneity.- Conclusions.- References.- Technical Questions.- 2 The Biology of Platelet Volume Heterogeneity.- Characteristics of Size-Dependent Platelet Subpopulations.- Relationship of Platelet Size to Platelet Age.- The Relationship of the Mean Platelet Volume to the Platelet Count.- Summary.- References.- Technical Questions.- 3 Is Platelet Heterogeneity Due to Ageing or Thrombopoiesis?.- Method of Separation of Platelets on Stractan Density Gradients.- Types of Experiments.- In Vivo Labelling.- Total Population Label.- Injection of Most Dense or Least Dense Platelets.- Injection and Re-isolation of Labelled Density Subpopulations.- Recovery of Ability of Platelets to Synthesize Thromboxane After Aspirin Administration.- Conclusions About the Relation Between Density and Survival of Rabbit Platelets.- Do Discontinuous Gradients Introduce Artefacts?.- Differences Between Most Dense and Least Dense Platelet Subpopulations.- Effect of Aggregating and Release-Inducing Agents on Platelet Density.- Effect on Density of Raising the Concentration of Cyclic AMP in Rabbit Platelets.- Changes in Density In Vivo.- Conclusions.- References.- Technical Questions.- Discussion (Chapters 1–3).- 4 Origins and Significance of Platelet Heterogeneity in a Non-human Primate Model.- Platelet Density.- Characterization of Young Platelets.- The Baboon Model of Acute Thrombocytopenia.- Platelet Kinetics.- Organ Localization.- Platelet Size.- Platelet Function.- Membrane Glycoproteins.- Platelet Organelle Content.- Platelet Enzymes.- Chronic Thrombocytopenia.- Acquired Platelet Alterations.- Conclusions.- References.- 5 Platelet Formation, Platelet Density and Platelet Ageing.- The Proplatelet Theory of Platelet Formation.- Proplatelet Formation in Bone Marrow.- Proplatelet Formation In Vitro.- Factors Controlling Proplatelet Formation.- Proplatelet Structure.- Proplatelets in Peripheral Blood.- Fragmentation of Proplatelets.- Alternative Mechanisms for Platelet Release.- When Do Individual Platelets Begin to Exist?.- Proplatelets and Platelet Volume Heterogeneity.- Platelet Density Heterogeneity and Platelet Ageing.- Preparation of Platelet Density Subpopulations.- Morphometric Analysis of Platelet Density Subpopulations.- Biochemical Properties of Platelet Density Subpopulations.- Functional Properties of Density-Separated Platelets.- Age-Dependent Properties of Platelets.- Platelet Population Labelling by MAO Inhibition.- The Recovery of MAO Activity in Platelet Density Subpopulations After Irreversible MAO Inhibition.- Interpretation of Labelling Studies of Density- Separated Platelets.- Possible Mechanisms for the Increase in Human Platelet Density with Platelet Age.- Platelet Density Heterogeneity in Pathological States.- Conclusions.- References.- 6 Characterization of Platelets and Megakaryocytes of the Wistar Furth Rat: An Animal Model with Inherently Large Mean Platelet Volume.- Materials and Methods.- Results.- Discussion.- References.- Technical Questions.- 7 The Circulating Megakaryocyte, Platelet Volume Heterogeneity and Thrombopoiesis.- The Concept of Bone Marrow Thrombopoiesis: How Did It Start?.- The Megakaryocyte Demarcation Membrane System and Platelet Territories.- Diapedesis and Sinusoidal Megakaryocytes.- Circulating Megakaryocytes.- Pulmonary Megakaryocytes.- Platelet Volume Heterogeneity.- Pulmonary Thrombopoiesis: A Simple Mechanism.- Conclusions.- References.- 8 The Genesis of Platelet Volume and Density Distributions.- Platelet Size Distributions From Normal Subjects Approximate Log-normality.- Circulating Platelet Populations of Widely Different Age Distributions Approximate Log-normality.- Platelet Volume Can Be Regulated.- Platelet Volume Is Inversely Correlated to Platelet Count.- Platelet Volume and Density Are Partially Correlated.- Platelet Function Is Linked to Platelet Size and Density.- Megakaryocyte Ploidy Heterogeneity Cannot Explain Log-normality.- Fragmentation and Growth of Megakaryocyte Cytoplasm Are Major Determinants of Platelet Size.- References.- Discussion (Chapters 7 and 8).- 9 Platelet Heterogeneity in Vascular Disease.- The Origin of Platelet Heterogeneity.- Normal Physiological Response to Change in Platelet Destruction.- The Control of Platelet Production.- Platelet Volume in Myocardial Infarction.- The Bleeding Time in Myocardial Infarction.- Platelet Volume and Megakaryocytes in Animal Models of Vascular Disease.- Conclusions.- References.- Technical Questions.- 10 The Heterogeneity of Platelets.- References.- Technical Questions.- General Discussion.- 11 Summing Up: Platelet Heterogeneity: Biology and Pathology.- Bone Marrow and Thrombopoiesis.- References.- Discussion.- 12 Chairman’s Commentary.- Technical Questions.- Basic Questions.