Biological Functions Lec 1 Dr Faten Zahra PDF

Biological functions Lec 1 Dr faten zahra Quality Control (QC) 1. Means to minimize errors and to provide patient with best care , through many steps. 2. The totality of features and characteristics of a product, process or service that bear...

Biological functions Lec 1 Dr faten zahra Quality Control (QC) 1. Means to minimize errors and to provide patient with best care , through many steps. 2. The totality of features and characteristics of a product, process or service that bear on its ability to satisfy stated or implied needs. 3. A series of analytical measurements used to assess the quality of the analytical data (The ―tools). So, QC is the process of detecting errors. Lab safety rules: Laboratory should be designed in such a way that you can work safely: 1. It must be easily cleaned. 2. Contains a sink for washing. 3. Illumination is adequate for all laboratory activities. Treat all body fluids as a potentially infectious material. A lab coat and gloves should be worn during laboratory work. Laboratory procedures divided into three stages :_ 1. Pre-analytical factors: are those factors that affect the laboratory results due to handling of the specimen sample prior to analysis. 2. The analytical factors: includes verification of instrument linearity, precision, accuracy, and overall reliability through the use of standard materials, quality control (QC) samples, procedures, and QC rules. 3. Post-analytical factors: include timely and accurate laboratory result reporting and other aspects that occur after the analysis phase. Pre-analytical factors: analytical factors Post-analytical factors: Reception Prepare the equipment, Test name and type of instruments and reagents specimen analyzed for use Test for request Perform the test and Test results clearly calculate the results Recording data & The measurement unit and history case reference range Preparation of patient The comment if found Collection and transport of the sample 1.Pre-analytical factors:_  Patient Identification: (Investigation)  Type of specimen:_ ( whole blood, plasma, serum ,urine , stool , semen )  Preparation of patient  Preparation tools for specimen handling such as ( tube , swabs,plaster,syringe, gloves , alcohol, tourniquet) , Preferably 2 tourniquet.  Notes :_ Take a sample fastly , if sample is blood, avoid hemolysis It's important to leave tourniquet only 2 minutes. Remove tourniquet before syringe removing.  If the sample for fasting blood sugar or kidney function, told patient to bring urine sample ( morning midstream urine ).  Note :_ Blood sugar excret in urine after 180 g/dl , due to ability of kidney " renal  threshold ". Fasting blood sugar need fasting for 6:8 hours. Lipid profile need fasting for 10 : 12 hours. 2hr Post prandial sugar :_ after 2hr from ( breakfast + take drug) , normal breakfast = daily breakfast. If fasting, post prandial blood sugar is not correct, patient should do glucose tolerance test. Glucose tolerance test :_ Who do this test :_ normal people , pregnant women, diabetic patient. Number of sample:_ 5 blood sample, 5 urine sample. Procedure Intensive care unit patient takes their sample from any place except cannula. Specimen Transport: Light, heat, evaporation, and exposure to the atmosphere will change many substances in routine clinical chemistry testing. Exposure of plasma samples to high temperatures can significantly lower potassium concentrations. 2.Analytical Variables Analytical Variables: Chemical analysis involves many steps and components. These include: specimen measurement, sample pretreatment, reagent volume measuring, sample and reagent mixing, incubation, reaction timing, reaction analysis, calculations, Result reporting. There are many analytical variables that must be carefully controlled: Water quality. Calibration of analytical balances. Calibration of volumetric glassware and pipettes. Stability of electrical power. Stability of temperature of heating baths, refrigerators, freezers and centrifuges. The Standard operating Procedure should contain the following: Procedure name, Clinical significance, Principle of method, Specimen of choice, Reagents and equipment's, Procedure, Reference values, Comments, References. 3. Post-analytical Variables:_ post-analysis includes reporting the results in a timely, accurate, legible manner to the appropriate health-care professionals while maintaining patient confidentiality. The ideal analytical method is accurate, precise, sensitive and specific. o Accurate: It gives a correct result, the result is nearly normal range for the test. o Precise: that is the same if repeated, reproducibility of the result. o Sensitive: It measures low concentrations of the analytes. o Specific: is not subject to interference by other substances. If we repeat the test , the difference between two sample " standard deviation " is 2.1 percent.  Lec 2 Heart biofunction The human heart provides a continuous blood circulation through the cardiac cycle and is one of the most vital organs in the human body. The heart works as a pump that pushes blood to the organs, tissues, and cells of body. Blood delivers oxygen and nutrients to every cell and removes the carbon dioxide and waste products made by those cells. Blood is carried from your heart to the rest of your body through a complex network of arteries, arterioles, and capillaries. Blood is returned to your heart through venules and veins Function of heart :_  Heart pumps the blood which contains nutrients to all organs, make excretion, do all things for our life.  By capillaries ( veins, arteries) , heart transport every substances in the body.  It responsible for PH , hemostsis ( mean stability).  Remove CO2 & metabolic wastes. Heart:_  It is a muscular organ , make heart beats.  It's auto pump. Note :_ Function of heart measures by blood test. Symptoms of heart disease:_ pain in left shoulder , tingling in the back , due to hypoxia ( low oxygen) or anoxia( no oxygen ) = occur deficiency of oxygen or arteriosclerosis, diabetes, clotting for blood. So heart disease results from hypoxia and anoxia. Exposure to anoxia is long or short , hypoxia is chronic or acute. Angina is reversible. Heart failure, heart attack is premenant, the scientific name for them is myocardial infarction. The part which dead in the heart called infarct. No occur regeneration for any muscle. Function of heart is similar to skeletal muscle. Diagnosis by blood tests :_ Enzyme Protein In muscle Myoglobin Blood gas CK= CPK and CK-MB Its isomers:_ MM (CK3), CK-BB (CK1) and CK- MB (CK2). In muscle:_ Troponin " specific for CBC heart " LDH " 5 isomers " 2 isomers In liver :_ Electrolytes : Na , K. AST Common In skeletal muscle and heart:_ CK-MB, LDH, AST , Myoglobin, raise through 4 hours ( max. Peak) and continue for 2 : 3 days so patient if he isn't do her test during one week , the result will be normal. Specific for heart :_ troponin, continue for two weeks. Total Creatine kinase (CK) ( not specific) It also known as creatine phosphokinase (CPK) or phospho-creatine kinase is an enzyme expressed by various tissues and cell types. What is Creatine? Creatine is produced by the body at rate of 1-2g/day from the amino acids, glycine, arginine and methionine. The liver is the major site of production but some is also produced in the kidney and pancreas. It exists as free creatine and creatinee phosphate (CP). CK catalyzes the conversion of creatine and consumes adenosine triphosphate (ATP) to create phosphocreatine and adenosine diphosphate (ADP). CK-isoenzymes " not specific " In the cells, the CK enzymes consist of two subunits, which can be either B (brain type) or M (muscle type). There are, therefore, three different isoenzymes: CK-MM (CK3):skeletal muscle CK-BB (CK1): brain CK-MB (CK2):heart Lactate dehydrogenase (LDH, or LD) It is an enzyme that is found in almost all body tissues but only a small amount of it is usually detectable in the blood. It usually stays contained within the tissues cells. When cells are damaged or destroyed, however, they release LDH into the bloodstream, causing blood levels to rise. For this reason, LDH is used as a general marker of injury to cells. Lactate dehydrogenase catalyzes the inter-conversion of pyruvate and lactate with concomitant inter-conversion of NADH and NAD+. It converts pyruvate, the final product of glycolysis to lactate when oxygen is absent or in short supply. This reaction is known as anaerobic homo-lactic fermentation and is an important way to regenerate NAD+ to allow glycolysis to continue. Lactate dehydrogenase isoenzymes :_ LDH functions as a tetramer and is made of two kinds of subunits, H and M, each of which are encoded by a different gene. This results in 5 different isoenzymes (2 homotetramers and 3 heterotetramers). The M subunit is found predominant in anaerobic tissues including skeletal muscle and liver. The H subunit is more commonly found in tissue with a ready source of oxygen and that metabolize lactate including the heart and the brain. 1) LDH-1 (4H) - in the heart 2) LDH-2 (3H1M) - in the reticuloendothelial system 3) LDH-3 (2H2M) - in the lungs 4) LDH-4 (1H3M) - in the kidneys 5) LDH-5 (4M) - in the liver and striated muscle We measure LDH Which contain 4 M. Myoglobin Myoglobin may be ordered as a cardiac biomarker, along with troponin, to help diagnose or rule out a heart attack. It has high affinity for oxygen than Hemoglobin. Troponins (TnI; TnT; cTnI; cTnT) Troponin tests are primarily ordered to evaluate people who have chest pain to see if they have had a heart attack or other damage to their heart. Either a cardiac specific troponin I or troponin T test can be performed, usually a laboratory will offer one test or the other Troponin tests are sometimes ordered along with other cardiac biomarkers, such as CK–MB or myoglobin. However, troponin are the preferred test for suspected heart attack because they are more specific for heart injury than other tests (which may become positive in skeletal muscle injury) and remain elevated for a longer period of time. Marker What Where What Time to Time to back When / How used found indicators increase CK Enzyme that Heart, Injury to 4 to 6 Normal in 48 Being phased out, exists in three brain, and muscle cells hours after to 72 hours, may be ordered different skeletal injury, unless due to prior to CK-M isoforms muscle peaks in continuing 18 to 24 injury hours CK-MB Heart- related Heart Injury (cell 4 to 6 hrs Returns to Not as specific as portion of total primarily, death to heart after heart normal in 24 Troponin for heart CK enzyme but also in attack, to 48 hours injury/attack, may skeletal peaks in unless be ordered when muscle 12 to 20 new/continual Troponin is not hour damage available, may be ordered to monitor new/continuing damage Myoglobin Small oxygen- Heart and Injury to heart Starts to Falls back to Ordered along with storing protein other or other rise within normal by Troponin, helps muscle muscle cells. 2 to 3 about one day diagnose heart cells Also elevated hours, after injury injury/attack with kidney peaks in 8 occurred problems. to 12 hours. Cardiac Components Heart Heart 4 to 8 Remains Ordered to help troponin of a injury/damag hours elevated for 7 assess prognosis muscle e to 14 days and diagnose heart Regulatory attack protein complex. Two cardiac specific isoforms: T and I LDH Enzyme Almost all General _ _ body marker of  tissues injury to cells Phased out, not specific AST Enzyme Heart, liver, Injury to liver, Phased out, not and muscle, or heart-specific muscles heart Hs-CRP Protein Associated Inflammatory _ Elevated with May help with process inflammation determine atheroscler prognosis of osis patients who’ve had heart attack BNP Hormone Heart’s left Heart failure _ Elevation Help diagnose and ventricle related to evaluate heart severity failure, prognosis, and to monitor therapy