Understanding Pathophysiology Chapter 4 Altered Cellular and Tissue Biology

Physiologic (adaptive) - answer-Reversible changes in cell size, number, phenotype, metabolic activity, or function of cells Atrophy - answer-Decrease in cellular size Hypertrophy - answer-Increase in cellular size Hyperplasia - answer-Increase in number of cells Dysplasia - answer-Deranged cellular growth Metaplasia - answer-Replacement of one type of cell with another Cellular Injury - answer-Occurs if cell unable to maintain homeostasis Reversible Cells recover Irreversible Cells die Hypoxic injury - answer-Single most common cause of cellular injury Results from: Reduced amount of oxygen in the air Loss of hemoglobin or decreased efficacy of hemoglobin Decreased production of red blood cells Diseases of the respiratory and cardiovascular systems Poisoning of the oxidative enzymes (cytochromes) within the cells Ischemia - answer-Most common cause of hypoxia (reduced blood supply) Ischemia-reperfusion injury - answer-Additional injury that can be caused by restoration of blood flow and oxygen Mechanisms: Oxidative stress Increased intracellular calcium Inflammation Complement activation Anoxia - answer-Total lack of oxygen Decrease in ATP, causing failure of sodium-potassium pump and sodium-calcium exchange Cellular swelling Vacuolation Reperfusion injury - answer-What is the cellular response of cells after hypoxic injury? Oxidative stress - answer-Occurs when excess ROS overwhelm endogenous antioxidant systems Free radical - answer-electrically uncharged atom or group of atoms that has an unpaired electron Free radicals and reactive oxygen species - answer-These two things cause these to happen: Lipid peroxidation Alteration of proteins Alteration of DNA Mitochondria Lipid peroxidation - answer-destruction of polyunsaturated lipids, leading to membrane damage and increased permeability Mitochondria - answer-Damage to this results in the failure of oxydative phosphorylation and ROS to damaged cellular components Chemical injury causing things - answer-Xenobiotics: Carbon tetrachloride Lead Carbon monoxide Ethanol Mercury Social or street drugs Xenobiotics - answer-include toxic mutagenic and carcinogenic chemicals Direct damage by chemical agents - answer-Chemicals and drugs injure cells by combining directly with critical molecular substances Chemotherapeutic drugs Drugs of abuse Hypersensitivity reactions by chemical agents - answer-Range from mild skin rashes to immune-mediated organ failure Unintentional and Intentional Injuries - answer-More common among men and higher rates among blacks Includes: Blunt force injuries Sharp force injuries Gunshot wounds Asphyxial injuries Blunt force injuries - answer-Result of application of mechanical force to body Results in tearing, shearing, or crushing of tissues Motor vehicle accidents and falls Contusions Lacerations Fractures Sharp force injuries - answer-Includes: Incised wound Stab wound Puncture wound Chopping wound Contusion (bruise) - answer-Bleeding into skin or underlying tissues; initial color will be red-purple, then blue-black Laceration - answer-tear or rip resulting when tensile strength of skin or tissue is exceeded; is ragged and irregular with abraded edges Fracture - answer-Blunt-force blows or impacts can cause bone to break or shatter Incised wound - answer-A wound that is longer than it is deep; wound can be straight or jagged with sharp, distinct edges without abrasion; usually produces significant external bleeding with little internal hemorrhage; noted in sharp force injuries and hesitation marks Stab wound - answer-A penetrating sharp-force injury that is deeper than it is long; if a sharp instrument is used, depths of wound are clean and distinct but can be abraded if object is inserted deeply and wider portion impacts skin Puncture wound - answer-instruments or objects with sharp points but without sharp edges produce puncture wounds; classic example is a wounded foot after stepping on a nail Chopping wound - answer-Heavy, edged instruments produce wounds with a combination of sharp and blunt force characteristics Asphyxial injuries: - answer-Caused by a failure of cells to receive or use oxygen Suffocation Strangulation Chemical asphyxiants Drowning Suffocation - answer-Choking asphyxiation is an example of what kind of asphyxial injury? Strangulation - answer-Hanging, ligature, and manual strangulation are examples of what kind of asphyxial injury? Chemical asphyxiants - answer-Cyanide and hydrogen sulfide Are examples of what kind of asphyxial injury? Drowning - answer-Drinking an ocean or lake are examples of what kind of asphyxial injury? Infectious Injury - answer-Pathogenicity of a microorganism Disease-producing potential determined by ability to: Invasion and destruction Toxin production Production of hypersensitivity reactions Cynaide - answer-Acts as an asphyxiant by combining with the ferric iron atom in cytochrome oxidase, thereby blocking intracellular use of oxygen Hydrogen sulfice - answer-brown tinged blood in addition to the nonspecific signs of asphyxiation Immunologic and Inflammatory Injury - answer-Phagocytic cells and Immune and inflammatory substances such as Histamine, antibodies, lymphokines, complement, and proteases result in membrane alterations Membrane alterations which leak potassium and allow water in Hypoxia - answer-Which of the following is the most common cause of cellular injury? Hypoxia Chemical injury from drugs Free radical-induced injury Chemical injury from pollutants Cellular accumulations (infiltrations): - answer-Abnormal amounts of various substances inside of cell Such as: Water Lipids and carbohydrates Glycogen Proteins Pigments Calcium Urate Cellular swelling (water accumulation) - answer-Caused by shift of extracellular water into the cells; the most common degenerative change;reversible and is an early manifestation of almost all types of cellular injury Mucopolysaccharidose - answer-Disease in which carbohydrates are ub excess Hepatic - answer-Lipid accumulation is most commonly seen in the _______ cells Glycogen - answer-The most common cause of _____ accumulation is the disorder of glucose metabolism (diabetes mellitus) Proteins - answer-Excessive amounts of _______ in the cytoplasm push against cellular organelles, disrupting organelle function and intracellular communication Pigment - answer-The most common exogenous pigment is carbon (coal dust), a pervasive air pollut