bài giảng DÒNG HỒNG cầu (phần 2)

Focus on RBCs: Figure 16-5c: Bone marrow Erythropoiesis Chapter 18 The Circulatory System: Blood Functions and properties of blood Plasma Blood cell production Erythrocytes Blood types Leukocytes Hemostasis Hematocrit Normal HCT: male = 46% female = 42% Abnormal HCT: > 56% polycythemi < 30% anemia Centrifuging blood forces formed elements to separate from plasma Hematocrit is % of blood volume that is composed of erythrocytes (RBCs) RBC Erythrocytes (RBCs) Disc-shaped cell with thick rim 7.5 µM diameter & 2.0 µm thick at rim Major function is gas transport lost all organelles during maturation and has biconcave shape which gives RBCs increased surface area/volume ratio increases diffusion rate of substances in & out of cell 33% of cytoplasm is hemoglobin (Hb) Hemoglobin is the red pigment that gives RBC its color O2 delivery to tissue and CO2 transport back to lungs cytoplasm contains enzyme, carbonic anhydrase (CAH) produces carbonic acid (H2CO3) from CO2 and water CAH has an important role in gas transport & pH balance RBC Structure Small and highly specialized disc Thin in middle and thicker at edge Figure 19–2d Erythrocytes on a Needle RBCs vs WBCs RBC an eosinophil Focus on RBCs: Figure 16-7a, b: Bone marrow leptocytes (target cells) - liver disease (obstructive jaundice) - post splenectomy - hemoglobinopathies (hypochromic anemias) beta thalassemia thalassemia Hgb C disease Hgb H disease relative increase of cell membrane > “target” formation schistocytes (cell fragments) indication of hemolysis - megaloblastic anemia - severe burns - traumatic hemolysis - microangiopathic hemolytic anemia “helmet cell” (helmet cells, triangular cells) acanthocytes (irregular surface spicules) irregularly spiculated cells with bulbous/rounded ends of spicules - abetalipoproteinemia - liver disease echinocytes (crenated cells, burr cells) regularly contracted cells with smooth surface undulation - uremia - artifact - hyperosmolarity - discocyte-echinocyte transformation (may be associated with reduced ATP of RBCs) bite cells Removal (“bites”) of membrane by splenic macrophages - G6PD deficiency dacrocytes (teardrop cells) - thalassemia - myelofibrosis drepanocytes (sickle cells) - sickle cell anemia Sickle-Cell Diseased Erythrocyte rouleaux lined up RBCs in a row - multiple myeloma basophilic stippling irregular basophilic granules (remnants of RNA) fine stippling: •increased production of RBCs (reticulocytosis) coarse stippling: •lead poisoning •impaired Hgb syntheisis •megaloblastic anemia •other sever anemias sideroblast/siderocyte inorganic iron-containing granules (Pappenheimer bodies) - sideroblastic anemia ring intermediate sideroblasts sideroblast siderocyte abnormally trapped iron in mitochondria forming a ring around nucleus - post splenectomy Howell-Jolly body remnant of nuclear chromatin single: •megaloblastic anemia •hemolytic anemia •post splenectomy multiple: •megaloblastic anemia •other abnormal erythropoiesis Heinz bodies denatured hemoglobin - G6PD deficiency Hypochromia Pencil Cells