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General Concepts in Pathophysiology

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General Concepts in Pathophysiology http://www.youtube.com/watch?feature=pla yer_detailpage&v=DmfgMu2ElS4 Homeostasis Cell physiology Mechanism of diseases “A dynamic, steady state of internal balance”. “Homeostasis is maintained by self-regulating feedback mechanisms”. (+ feedback or – feedback) “The body’s ability to physiologically regulate, to adapt to minor fluctuations”. “Small fluctuations in the environment don’t normally impact the body because it has many mechanisms for maintaining homeostasis”. Cell Components Cell Functions Cell Types Organelle that creates proteins Organelle that creates ATP Barrier, receptors Organelles that maintain the cells shape Organelle that contains digestive enzymes Control center (RNA, DNA) Organelle that creates lipids Organelle that creates carbohydrates Welcome to the highly guarded - air-tight Nuclear Vault…Like the Fort Knox, its barricaded from an assault Like the Dura Mater - double-nuclear envelope. It's the home of the Library of Chromosomes Securely protected - like bullions of gold… Like City Blueprints - DNA originals When it's transcribing messages in form of codes…In the nucleolus - RNA to ribosomes. The nucleus of a cell contains genetic information in the form of DNA. DNA is arranged in a loose and diffuse state called Chromatins which are later condensed before cell division into chromosomes. The Nuclear Membrane is a double-walled structure (the double lipid bi-layer aka nuclear envelope) within a cell to protect even those things within the cytoplasm of the cell. It protects the genetic information from damage - damage that can cause programmed cell death (apoptosis) or even worse - cancer - if it damages the contents of the nucleus. Ribosomes and RNA are also in the nucleus… Ribosomes are used in translation of messenger RNA into proteins which occurs in the cytoplasm, but ribosomes are assembled in the nucleus via rRNA. Transcription occurs in the nucleus of the cell - where specific DNA genes codes are used to make mRNA. The nucleus medium is called nucleoplasm which is similar to the cytoplasmic fluid in the cytoplasm. Nuclear pores allow only certain small molecules to pass in and out of the nucleus. http://www.youtube.com/watch?list=UULWN DHy7oMDna7Tces_ZnDQ&feature=player_d etailpage&v=mAdTroXxs4M Movement (muscles) Conductivity (nerves) Absorption (kidneys and intestines) Secretion (adrenal glands, testis, ovaries) Excretion (lysosomes) Respiration (production of ATP) (mitochondria) Reproduction mitosis, which results in 2 cells identical to parent cell,…occurs in all cells; meiosis, which results in 4 gametes each with half the number of chromosomes of the parent cell….occurs only in reproductive cells. Connective tissue cell Epithelial cell Muscle cell Nerve cell Provides physical support (bones, cartilage, ligaments, tendon, fascia) Facilitates the movement of fluids and nutrients Protects against infections Scattered throughout an extracellular matrix Collagen is the most abundant component of connective tissue http://mycozynook.com/102RGCh20OH.htm Protect or enclose organs, as well as protect all body surfaces. Produce mucus or other secretions. Epithelial tissues are named for the number of layers they contain and for the shape of their cells http://mycozynook.com/102RGCh20OH.htm Simple Squamous (flat) Capillary and air sac linings (One layer) Cuboidal (cube) Kidney tubules and thyroid gland Columnar (column) Intestinal lining Stratified Squamous (flat) Skin (More than one layer) Cuboidal (cube) Sweat glands and mammary glands Columnar (column) Pharynx and anus Pseudostratified Columnar Upper respiratory tract (one layer but looks like more) Muscle tissue functions in movement •Skeletal muscle -Responsible for voluntary body movements •Cardiac muscle -Forms the heart •Smooth muscle -Responsible for involuntary organ motions Ex: intestinal movements (peristalsis) http://mycozynook.com/102RGCh20OH.htm Nervous tissue forms a communication network •Senses stimuli and rapidly transmits information •Neuron: structural and functional unit of nervous tissue specialized to conduct electrical impulses •Dendrites convey information toward the neuron cell body •Axons convey information away from the neuron cell body http://mycozynook.com/102RGCh20OH.htm When homeostasis is not maintained….there will be disease. “Disease is a structural (visible lesion) or functional (no visible lesion) change in the body that is harmful to the organism.” “Disease occurs when the cellular environment changes to such a degree that tissues are no longer able to perform their function optimally.” The study of disease is known as Pathology The study of “basic structural and functional changes associated with a disease, as well the study of causes (etiology) that lead to those changes, or the sequence of events that leads from structural or functional abnormalities to clinical manifestations. Symptoms Perceived by the patient Signs Physical observations made by the clinician Test results Cell Adaptation (reversible injury) Cell Injury Mild injury: Cell Degeneration Cell Death (irreversible injury) Apoptosis Necrosis Cell Adaptation (reversible injury) Dysplasia (atypical cell growth that has the potential of developing into a cancer) Metaplasia (the replacement of one tissue type with another) Hyperplasia (increase in the number of cells) Hypertrophy (increase in size of cells) Atrophy (complete wasting away of a cell) Hypoxia (ischemia, cardiopulmonary failure, anemia) Infection Chemical injury Physical injury Nutritional/vitamin deficiency or excess Inflammation Body’s attempt at limiting injury and of removing necrotic debris. Repair Body’s attempt to replace dead cells either by regeneration of the original tissue, or replacement by connective tissue Necrosis Death of tissue Reversible Changes after injury (preservation of the nucleus) Irreversible Changes (fragmentation of the nucleus) Normal Swelling Condensation Condensation of Cell of cytoplasm of nucleus cytoplasm Rupture of the cell membrane Depletion of the cell’s energy system Liquefaction Necrosis typical of a bacterial or fungal infection; involves tissue digestion Coagulation Necrosis typical of ischemia or infarction; the tissue appears to coagulate Caseous Necrosis (coagulative necrosis that is specific to an infection with tuberculosis; caseous means ‘cheesy’) Gangrenous Necrosis (combination of coagulation necrosis (due to ischemia) and liquefaction necrosis (due to the bacterial super-infection) Fat Necrosis Death of fat cells due to the release of enzymes in tissue containing fat cells http://www.youtube.com/watch?f eature=player_detailpage&v=xKXIv 6y6QP0 Seven Causes of Cellular Injury Loss of nucleus with a preserved architecture. Hook 1.Hypoxia It's a broad and complex field, seeking to understand 2. Infectious Lyrical Lectures and cellular destruction The mechanism of cellular injury and how the body can 3. Hypersensitivity By hydrolytic enzymes -- Liquefactive Necrosis -- Respond and repair -- cellular adaptation 4. Autoimmune Occurs in abscesses -- brain infarcts -- or pancreas Of which 7 causes are identified -- let's make haste (i.e.) Leukocyte enzymes causing pus is the fanciest. 5. Congenital Most common is hypoxia -- second is infectious 6. Chemical/Physical Caseus -- just a combination of the first two. Hypersensitivity -- autoimmune are next -- run the 7. Nutritional/Vitamin excess of deficiency Friable and cottage-cheese -- it'll hurt you and the nurse, too. check list Cellular Adaptation: In the case of TB -- quarantine the fella... Congenital, chemical, physical forms of injury Dysplasia Ella... Ella... like Nelson Mandella. Nutritional or vitamin -- excess or deficiency Metaplasia Hyperplasia Fibrinoid -- histologically resembles fibrin V3 Hypertrophy Surprisingly -- homogenous -- microscopically dive in Chemical injury includes Drugs and Poisons; Atrophy Gangrenous tissue is sort of like a hybrid More than noise pollution -- occupational exposures Dry is coagulative -- Wet is liquefactive. Asbestosis -- carbon monoxide poisoning Different Types of Necrosis Social/lifestyle choices -- alcohol/cigarette smoking Liguefactive Hook Coagulative It's a broad and complex field, seeking to understand Illicit drug overdosing and recreational potions. Gangrenous The mechanism of cellular injury and how the body can Physical forms of injury include blunt force and Fibrinoid Respond and repair -- cellular adaptation Penetrating trauma -- like gunshot wounds. Of which 7 causes are identified -- let's make haste Pressure changes -- radiation -- burns and frostbite, too. Fat Caseous Most common is hypoxia -- second is infectious Nutritional/Vitamin imbalances causes injury, Hook Hypersensitivity -- autoimmune are next -- run the Either in excess or by a deficiency. It's a broad and complex field, seeking to understand check list Inadequate calorie or protein intake like neglected The mechanism of cellular injury and how the body can Congenital, chemical, physical forms of injury Kids with Marasmus or teens anorexic. Respond and repair -- cellular adaptation Nutritional or vitamin -- excess or deficiency Of which 7 causes are identified -- let's make haste Excess calorie intake leads to Obesity: V2 Increased risk of atherosclerosis & Diabetes. Most common is hypoxia -- second is infectious The most common is hypoxia -- defined as lack of oxygen Vitamin deficiencies -- from A to Z Hypersensitivity -- autoimmune are next -- run the The cell's inability to synthesize energy I'll cover it all
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