Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download 8_1_1-BloodLecture
Transcript
Blood QuickTime™ and a decompressor are needed to see this picture. Blood Connective tissue Transports substances to maintain homeostasis=main function Average adult has 5 liters of blood Blood is 4 times more viscous as water Hematocrit measures # cells/volume 45% is made of rbc, wbc, platelets 55% plasma (water, amino acids, proteins, carbohydrates, lipids, vitamins, hormones, electrolytes, cellular waste) What are the general characteristics of Red blood cells? Erythrocytes – Biconcave disk, 7.5 micrometers – Transport gas – No nucleus when mature – 1/3 hemoglobin (has iron and makes blood red) Oxyhemoglobin Deoxyhemolgobin Immature RBCs have nuclei Cannot divide-no protein synthesis or division Extremely flexible Sickle cell is caused by an abnormal form of hemoglobin RBC Counts 4,600,000/cubic centimeter is normal Number of circulating red cells determines oxygen carrying capacity Each RBC is capable of transporting up to four oxygen (O2) molecules Destruction of RBCs Average RBC lives 120 days As they age, they become fragile Macrophages destroy old/damaged rbcs in liver and spleen Recycled to hematopoietic tissue in red bone marrow Hemeironbiliverdinbilirubinbile Construction of RBCs= Hematopoiesis/Erythropoeisis Prenatal-yolk sac, liver, spleen Postnatal-red bone marrow Erythropoietin controls rate of RBC synthesis – Kidneys and liver respond to oxygen debt Dietary Factors B-Complex Vitamins (B12 and Folic acid) – Needed for DNA synthesis – Hematopoietic tissue is especially vulnerable to deficiency Iron – Absorbed slowly from food – reused Anemia- RBC disorder reduction of oxygen-carrying capacity of blood Too few RBCs Made – Iron defeciency – B complex deficiency – Erythropoietin deficiency Too many RBCs destroyed – Sickle cell anemia – Sickle trait – Thallasemias Alpha hemoglobin chain Beta hemoglobin chain Small rbcs Artist’s rendering of the 3D structure of the proteien hemoglobin Normal blood cells White Blood Cells- leukocytes Neutrophils-lobed nucleus – 54% to 62% leukocytes – Stain purple, granulocyte Eosinophils – Stain red, 1-3%-granulocyte Basophils-, 1%-granulocyte Monocytes- largest, 3-9%- agranulocyte Lymphocytes- small, round, 25-33%, long-livedagranulocyte. These function to attack antigens White Blood Cell Counts 5,000-10,000 is normal A rise indicates infection-leukocytosis A rise also occurs with some leukemias A decrease (leukopenia) may indicate viral infections Differential White Blood Cell Count Normal values for total WBC and differential in adult males and females are: Total WBC: 4,500 - 10,000 Bands or stabs: 3 - 5 % Granulocytes (or polymorphonuclears) Neutrophils (or segs): 54 - 67% relative value (2500-7000 absolute value) Eosinophils: 1 - 3% relative value (100-300 absolute value) Basophils: 0.4% - 1% relative value (40-100 absolute value) Agranulocytes (or mononuclears) Lymphocytes: 25 - 35% relative value (1700-3500 absolute value) Moncytes: 4 - 6% relative value (200-600 absolute value Normal ‘DIFF’ Normal values for total WBC and differential in adult males and females are: Total WBC: 4,500 - 10,000 Bands or stabs: 3 - 5 % Granulocytes (or polymorphonuclears) – Neutrophils (or segs): 50 - 70% relative value (2500-7000 absolute value) – Eosinophils: 1 - 3% relative value (100-300 absolute value) – Basophils: 0.4% - 1% relative value (40-100 absolute value) Agranulocytes (or mononuclears) – Lymphocytes: 25 - 35% relative value (1700-3500 absolute value) – Moncytes: 4 - 6% relative value (200-600 absolute value What Diffs may Indicate: Increased neutrophils indicates a bacterial infection Increased eosinophils-allergic reaction, parasitic infections Low lymphocytes-HIV Low basophil count with low neutrophil count may indicate future leukemia, basophils increase during infections and release histomines Elevated monocytes: - chronic inflammation - stress response - hyperadrenocorticism - immune mediated disease - pyogranulomatous disease - necrosis - red cell regeneration Functions of WBCs Protect against infection Phagocytize bacterial cells Produce antibodies Diapedesis - allows WBCs to leave circulation Phagocytes contain lysosomes to break down Release heparin and histamine (basophils) – Heparin prevents clots – Histamine increases blood flow Lymphoyctes – Immunity by antibody production Pus is made of leukocytes, bacteria, and Platelets (thrombocytes) Fragmented megakaryocytes No nucleus Live 10 days 130,000-360,000 is normal Patients with leukemia bleed due to a platelet deficiency Initiate blood clots Scanning electron microscope image of a group of platelets forming a clot Plasma Plasma proteins – Albumins Small, 60%, regulate water movement, depleted by dehydration – Globulins 36% of plasma proteins – Alpha, bets, and gamma – Transport lipids and fat-soluble vitamins – antibodies – Fibrinogen 4%, blood coagulation Converted to fibrin during blood coagulation Nutrients in Plasma Plasma nutrients – Amino acids – Sugars – Nucleotides – Lipids Lipoprotein molecules – VLDL-triglycerides – LDL-cholesterol – HDL-high protein Dissolved Gases in Plasma Oxygen Carbon dioxide Nitrogen Electrolytes in Plasma Sodium Potassium Calcium Magnesium Chloride Bicarbonate Phosphate Sulfate Hemostasis Vasospasm, a few minutes - smooth muscles contract Platelet plug, serotonin released, vasoconstriction Blood Coagulation-forms a clot, many clotting factors and is most effective hemostatic mechanism – Prothrombin to thromgin to fibrinogen to fibrin to clot – Positive feedback RBCs stuck in a web of fibrin What keeps blood from clotting? Coagulation is usually limited to blood that is standing still More on ClottingHematoma - many clots due to blood leakage aka “bruise” Thrombus - abnormal blood clot in a vessel Embolus - a dislodged thrombus, blocks blood flow Atherosclerosis - accumulations of fatty deposits along the wall of an artery Blood Groups and Transfusions 1665 - The first Blood transfusions of record take place. Animal experiments conducted by Richard Lower, an Oxford physician started as dog-to-dog experiments and proceeded to animal-tohuman over the next two years. Dogs were kept alive by the transfusion of blood from other dogs. 1667 - Jean-Baptiste Denis in France reported successful transfusions from sheep to humans. 1678 - Transfusion from animals to humans, having been tried in many different ways, was deemed to be unsuccessful, and was subsequently outlawed by the Paris Society of Physicians because of adverse reactions, many resulting in death. 1795 - In Philadelphia an American physician, Philip Syng Physick, performed the first known human Blood transfusion, although he did not publish the particulars. Landsteiner- father of blood banking More History… 1818 - James Blundell, a British obstetrician, performed the first successful transfusion of human Blood to a patient for the treatment of postpartum hemorrhage. Using the patient's husband as a donor, he extracted a small amount of Blood from the husband's arm and, using a syringe, he successfully transfused the wife. Between 1825 and 1830, he performed ten documented transfusions, five of which proved beneficial to his patients, and published these results. He also devised various instruments for performing Blood transfusions. 1840 - In London England, Samuel Armstrong Lane, aided by consultant Dr. Blundell, performed the first successful whole Blood transfusion to treat hemophilia. 1867 - English surgeon Joseph Lister utilized antiseptics to control infection during Blood transfusions. 1873 to 1880 - Physicians in the United States are documented, during these years, to have transfused milk (from cows and goats) to humans. 1884 - Saline infusion replaced milk as a 'Blood substitute' due to increased frequency of adverse reaction to milk. 1901 - Karl Landsteiner, an Austrian physician, and the most important individual in the field of Blood transfusion, documented the first three human Blood groups (based on substances present on the red Blood cells), A, B and O. 1902 - A fourth main Blood type, AB was found by A. Decastrello and A. Antigens and Antibodies Antigens on RBC Antibodies in the plasma ABO group and Rh group can cause serious transfusion reactions – Mismatched blood Clotting, hemolysis, jaundice, kidney failure ABO Erythrocytes contain 1 of 4 antigen combinations –A –B – AB – None Antibodies Synthesized at 2 to 8 months If you are type A, you synthesize anti–b, can get A and O blood If you are type B, you synthesize anti-a, can get B and O blood If you are type O, you synthesize both anti-a and anti-b, universal donor, only O If you are type AB, you synthesize no antibodies, universal recipient, any type of blood OK Rh Factor Rh (rhesus monkey) Antigen D present: Rh Positive (there are other antigens that can create problems as well) Antigen D absent: Rh negative Rh negative individuals cannot be transfued with positive blood once exposed to it Rh negative mother can develop antibodies to RH positive baby – BLUE BABIES, ERYTHROBLASTOSIS FETALIS, DESTROY FETAL CELLS, RhoGAM shots are now given –must be within 72 hours of Rh Positive contact (miscarry, amniocentesis, abortion, birth)
