Platelet Transfusion
The transfer of blood platelets from a donor to a recipient or reinfusion to the donor.
Blood Transfusion
Blood Platelets
Thrombocytopenia
A subnormal level of BLOOD PLATELETS.
Plateletpheresis
Erythrocyte Transfusion
Platelet Aggregation
The attachment of PLATELETS to one another. This clumping together can be induced by a number of agents (e.g., THROMBIN; COLLAGEN) and is part of the mechanism leading to the formation of a THROMBUS.
Blood Component Transfusion
The transfer of blood components such as erythrocytes, leukocytes, platelets, and plasma from a donor to a recipient or back to the donor. This process differs from the procedures undertaken in PLASMAPHERESIS and types of CYTAPHERESIS; (PLATELETPHERESIS and LEUKAPHERESIS) where, following the removal of plasma or the specific cell components, the remainder is transfused back to the donor.
Antigens, Human Platelet
Human alloantigens expressed only on platelets, specifically on platelet membrane glycoproteins. These platelet-specific antigens are immunogenic and can result in pathological reactions to transfusion therapy.
Thrombocytopenia, Neonatal Alloimmune
A condition in newborns caused by immunity of the mother to PLATELET ALLOANTIGENS on the fetal platelets. The PLATELETS, coated with maternal ANTIBODIES, are destroyed and removed by the fetal MONONUCLEAR PHAGOCYTE SYSTEM. Affected infants may have INTRACRANIAL HEMORRHAGES.
Isoantibodies
Antibodies from an individual that react with ISOANTIGENS of another individual of the same species.
Blood Transfusion, Intrauterine
In utero transfusion of BLOOD into the FETUS for the treatment of FETAL DISEASES, such as fetal erythroblastosis (ERYTHROBLASTOSIS, FETAL).
Blood Transfusion, Autologous
Blood Grouping and Crossmatching
Testing erythrocytes to determine presence or absence of blood-group antigens, testing of serum to determine the presence or absence of antibodies to these antigens, and selecting biocompatible blood by crossmatching samples from the donor against samples from the recipient. Crossmatching is performed prior to transfusion.
Platelet Adhesiveness
Blood Preservation
Exchange Transfusion, Whole Blood
Repetitive withdrawal of small amounts of blood and replacement with donor blood until a large proportion of the blood volume has been exchanged. Used in treatment of fetal erythroblastosis, hepatic coma, sickle cell anemia, disseminated intravascular coagulation, septicemia, burns, thrombotic thrombopenic purpura, and fulminant malaria.
Platelet Membrane Glycoproteins
Surface glycoproteins on platelets which have a key role in hemostasis and thrombosis such as platelet adhesion and aggregation. Many of these are receptors.
Hematology
Blood Component Removal
Blood Donors
'Blood donors' are individuals who voluntarily and safely donate a specific amount of their own blood, which can be further separated into components, to be used for transfusion purposes or for manufacturing medical products, without receiving remuneration that is intended to reward them financially.
Blood Group Incompatibility
An antigenic mismatch between donor and recipient blood. Antibodies present in the recipient's serum may be directed against antigens in the donor product. Such a mismatch may result in a transfusion reaction in which, for example, donor blood is hemolyzed. (From Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984).
Anemia, Aplastic
A form of anemia in which the bone marrow fails to produce adequate numbers of peripheral blood elements.
Platelet Factor 4
A CXC chemokine that is found in the alpha granules of PLATELETS. The protein has a molecular size of 7800 kDa and can occur as a monomer, a dimer or a tetramer depending upon its concentration in solution. Platelet factor 4 has a high affinity for HEPARIN and is often found complexed with GLYCOPROTEINS such as PROTEIN C.
Thrombopoietin
A humoral factor that stimulates the production of thrombocytes (BLOOD PLATELETS). Thrombopoietin stimulates the proliferation of bone marrow MEGAKARYOCYTES and their release of blood platelets. The process is called THROMBOPOIESIS.
Fetofetal Transfusion
Passage of blood from one fetus to another via an arteriovenous communication or other shunt, in a monozygotic twin pregnancy. It results in anemia in one twin and polycythemia in the other. (Lee et al., Wintrobe's Clinical Hematology, 9th ed, p737-8)
Anemia, Refractory
A severe sometimes chronic anemia, usually macrocytic in type, that does not respond to ordinary antianemic therapy.
Hemostasis
Bleeding Time
Thrombasthenia
A congenital bleeding disorder with prolonged bleeding time, absence of aggregation of platelets in response to most agents, especially ADP, and impaired or absent clot retraction. Platelet membranes are deficient in or have a defect in the glycoprotein IIb-IIIa complex (PLATELET GLYCOPROTEIN GPIIB-IIIA COMPLEX).
Leukemia
A progressive, malignant disease of the blood-forming organs, characterized by distorted proliferation and development of leukocytes and their precursors in the blood and bone marrow. Leukemias were originally termed acute or chronic based on life expectancy but now are classified according to cellular maturity. Acute leukemias consist of predominately immature cells; chronic leukemias are composed of more mature cells. (From The Merck Manual, 2006)
Platelet Function Tests
HLA Antigens
Platelet Glycoprotein GPIIb-IIIa Complex
Platelet membrane glycoprotein complex important for platelet adhesion and aggregation. It is an integrin complex containing INTEGRIN ALPHAIIB and INTEGRIN BETA3 which recognizes the arginine-glycine-aspartic acid (RGD) sequence present on several adhesive proteins. As such, it is a receptor for FIBRINOGEN; VON WILLEBRAND FACTOR; FIBRONECTIN; VITRONECTIN; and THROMBOSPONDINS. A deficiency of GPIIb-IIIa results in GLANZMANN THROMBASTHENIA.
Platelet Activating Factor
A phospholipid derivative formed by PLATELETS; BASOPHILS; NEUTROPHILS; MONOCYTES; and MACROPHAGES. It is a potent platelet aggregating agent and inducer of systemic anaphylactic symptoms, including HYPOTENSION; THROMBOCYTOPENIA; NEUTROPENIA; and BRONCHOCONSTRICTION.
Thrombopoiesis
The process of generating thrombocytes (BLOOD PLATELETS) from the pluripotent HEMATOPOIETIC STEM CELLS in the BONE MARROW via the MEGAKARYOCYTES. The humoral factor with thrombopoiesis-stimulating activity is designated THROMBOPOIETIN.
Interleukin-11
A lymphohematopoietic cytokine that plays a role in regulating the proliferation of ERYTHROID PRECURSOR CELLS. It induces maturation of MEGAKARYOCYTES which results in increased production of BLOOD PLATELETS. Interleukin-11 was also initially described as an inhibitor of ADIPOGENESIS of cultured preadipocytes.
Leukapheresis
Megakaryocytes
Very large BONE MARROW CELLS which release mature BLOOD PLATELETS.
Pancytopenia
Deficiency of all three cell elements of the blood, erythrocytes, leukocytes and platelets.
Hematopoietic Stem Cell Transplantation
Transfer of HEMATOPOIETIC STEM CELLS from BONE MARROW or BLOOD between individuals within the same species (TRANSPLANTATION, HOMOLOGOUS) or transfer within the same individual (TRANSPLANTATION, AUTOLOGOUS). Hematopoietic stem cell transplantation has been used as an alternative to BONE MARROW TRANSPLANTATION in the treatment of a variety of neoplasms.
ABO Blood-Group System
The major human blood type system which depends on the presence or absence of two antigens A and B. Type O occurs when neither A nor B is present and AB when both are present. A and B are genetic factors that determine the presence of enzymes for the synthesis of certain glycoproteins mainly in the red cell membrane.
Platelet Glycoprotein GPIb-IX Complex
Platelet membrane glycoprotein complex essential for normal platelet adhesion and clot formation at sites of vascular injury. It is composed of three polypeptides, GPIb alpha, GPIb beta, and GPIX. Glycoprotein Ib functions as a receptor for von Willebrand factor and for thrombin. Congenital deficiency of the GPIb-IX complex results in Bernard-Soulier syndrome. The platelet glycoprotein GPV associates with GPIb-IX and is also absent in Bernard-Soulier syndrome.
Thrombelastography
Purpura, Thrombocytopenic, Idiopathic
Thrombocytopenia occurring in the absence of toxic exposure or a disease associated with decreased platelets. It is mediated by immune mechanisms, in most cases IMMUNOGLOBULIN G autoantibodies which attach to platelets and subsequently undergo destruction by macrophages. The disease is seen in acute (affecting children) and chronic (adult) forms.
Granulocyte Colony-Stimulating Factor
A glycoprotein of MW 25 kDa containing internal disulfide bonds. It induces the survival, proliferation, and differentiation of neutrophilic granulocyte precursor cells and functionally activates mature blood neutrophils. Among the family of colony-stimulating factors, G-CSF is the most potent inducer of terminal differentiation to granulocytes and macrophages of leukemic myeloid cell lines.
Treatment Outcome
Thrombin
An enzyme formed from PROTHROMBIN that converts FIBRINOGEN to FIBRIN.
Retrospective Studies
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
Histocompatibility Testing
Identification of the major histocompatibility antigens of transplant DONORS and potential recipients, usually by serological tests. Donor and recipient pairs should be of identical ABO blood group, and in addition should be matched as closely as possible for HISTOCOMPATIBILITY ANTIGENS in order to minimize the likelihood of allograft rejection. (King, Dictionary of Genetics, 4th ed)
Bone Marrow Transplantation
The transference of BONE MARROW from one human or animal to another for a variety of purposes including HEMATOPOIETIC STEM CELL TRANSPLANTATION or MESENCHYMAL STEM CELL TRANSPLANTATION.
Leukocyte Transfusion
The transfer of leukocytes from a donor to a recipient or reinfusion to the donor.
Transplantation, Autologous
Leukemia, Myeloid
Form of leukemia characterized by an uncontrolled proliferation of the myeloid lineage and their precursors (MYELOID PROGENITOR CELLS) in the bone marrow and other sites.
Adenosine Diphosphate
Isoantigens
Antigens that exist in alternative (allelic) forms in a single species. When an isoantigen is encountered by species members who lack it, an immune response is induced. Typical isoantigens are the BLOOD GROUP ANTIGENS.
Cyclophosphamide
Precursor of an alkylating nitrogen mustard antineoplastic and immunosuppressive agent that must be activated in the LIVER to form the active aldophosphamide. It has been used in the treatment of LYMPHOMA and LEUKEMIA. Its side effect, ALOPECIA, has been used for defleecing sheep. Cyclophosphamide may also cause sterility, birth defects, mutations, and cancer.
Myelodysplastic Syndromes
Clonal hematopoietic stem cell disorders characterized by dysplasia in one or more hematopoietic cell lineages. They predominantly affect patients over 60, are considered preleukemic conditions, and have high probability of transformation into ACUTE MYELOID LEUKEMIA.
Disseminated Intravascular Coagulation
Prospective Studies
Immunization
Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves administration of ANTIGENS or IMMUNOLOGIC ADJUVANTS. PASSIVE IMMUNIZATION involves administration of IMMUNE SERA or LYMPHOCYTES or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).
Bone Marrow Diseases
Bone marrow diseases, also known as hematologic or blood disorders, refer to conditions that affect the production and function of blood cells within the bone marrow, such as leukemia, lymphoma, myeloma, and aplastic anemia, potentially leading to complications like anemia, neutropenia, thrombocytopenia, and increased susceptibility to infections or bleeding.
Fibrinogen
Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.
Antineoplastic Combined Chemotherapy Protocols
The use of two or more chemicals simultaneously or sequentially in the drug therapy of neoplasms. The drugs need not be in the same dosage form.
Leukocyte Count
The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.
Transplantation, Homologous
Lymphoma, Non-Hodgkin
Any of a group of malignant tumors of lymphoid tissue that differ from HODGKIN DISEASE, being more heterogeneous with respect to malignant cell lineage, clinical course, prognosis, and therapy. The only common feature among these tumors is the absence of giant REED-STERNBERG CELLS, a characteristic of Hodgkin's disease.
P-Selectin
Antigens, CD34
Hemoglobins
Anemia, Neonatal
The mildest form of erythroblastosis fetalis in which anemia is the chief manifestation.
Leukemia, Myeloid, Acute
Etoposide
A semisynthetic derivative of PODOPHYLLOTOXIN that exhibits antitumor activity. Etoposide inhibits DNA synthesis by forming a complex with topoisomerase II and DNA. This complex induces breaks in double stranded DNA and prevents repair by topoisomerase II binding. Accumulated breaks in DNA prevent entry into the mitotic phase of cell division, and lead to cell death. Etoposide acts primarily in the G2 and S phases of the cell cycle.
Erythroblastosis, Fetal
A condition characterized by the abnormal presence of ERYTHROBLASTS in the circulation of the FETUS or NEWBORNS. It is a disorder due to BLOOD GROUP INCOMPATIBILITY, such as the maternal alloimmunization by fetal antigen RH FACTORS leading to HEMOLYSIS of ERYTHROCYTES, hemolytic anemia (ANEMIA, HEMOLYTIC), general edema (HYDROPS FETALIS), and SEVERE JAUNDICE IN NEWBORN.
Hematopoietic Stem Cell Mobilization
The release of stem cells from the bone marrow into the peripheral blood circulation for the purpose of leukapheresis, prior to stem cell transplantation. Hematopoietic growth factors or chemotherapeutic agents often are used to stimulate the mobilization.
Antibodies
Graft Survival
Leukocytes
White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).
Postoperative Hemorrhage
Hematopoiesis
The development and formation of various types of BLOOD CELLS. Hematopoiesis can take place in the BONE MARROW (medullary) or outside the bone marrow (HEMATOPOIESIS, EXTRAMEDULLARY).
von Willebrand Factor
A high-molecular-weight plasma protein, produced by endothelial cells and megakaryocytes, that is part of the factor VIII/von Willebrand factor complex. The von Willebrand factor has receptors for collagen, platelets, and ristocetin activity as well as the immunologically distinct antigenic determinants. It functions in adhesion of platelets to collagen and hemostatic plug formation. The prolonged bleeding time in VON WILLEBRAND DISEASES is due to the deficiency of this factor.
Hepatic Veno-Occlusive Disease
Liver disease that is caused by injuries to the ENDOTHELIAL CELLS of the vessels and subendothelial EDEMA, but not by THROMBOSIS. Extracellular matrix, rich in FIBRONECTINS, is usually deposited around the HEPATIC VEINS leading to venous outflow occlusion and sinusoidal obstruction.