Pathology Chapter 1
ALT (alanine aminotransferase)
(Highest in the liver, more specific than AST) Used to evaluate liver disorders, ALT is increased longer than AST
LDH (lactate dehydrogenase)
(Non-Specific; highest concentrations in: Heart, liver, muscles, kidneys and rbc's) rises in 12-24 hours, peak at 48-72 hours, may remain increased after 10 days
AST (aspartate aminotransferase)
-enzyme found mainly in heart muscle and liver, moderate amounts found; skeletal muscles, kidneys, pancreas -Rises with cellular injury, liver injury (hepatitis, necrosis), pancreatitis, musculoskeletal trauma
physiologic atrophy
-occurs with early development -ex: the thymus gland undergoes physiologic atrophy during childhood
hypoxia/anoxia Clinical causes
1. Airway obstruction(suffocation secondary to drowning) 2. Inadequate transfer of O2 across the respiratory membrane (pneumonia) 3. Inadequate transfer of O2 into the blood (Anemia) 4. inability of cell to use O2 for cellular respiration ( cyanide poisoning which prevents oxidative phosphorylation)
3 stages of irreversible cell injury
1. Pyknosis - (condensation of chromatin) 2. Karyorrhexis - (fragmentation of nucleus) 3. Karyolysis - (lysis of chromatin)
Alcohol can stimulate fat accumulation in the liver through various mechanisms
1. free fatty acids mobilized at an increased rate from peripheral stores 2. increased fat formation (neolipogenesis) from glucose, amino acids & alcohol 3. decreased triglyceride usage due to enzyme inhibition 4. decrease in apoprotein synthesis & export of fat in form of lipoproteins
Ubiquitin
A small protein that is covalently linked to other cellular proteins identified for breakdown by the proteosome.
1-10 Which of the following cells is most likely to undergo apoptosis? A. A cell that has been anoxic for 30 minutes B. A CELL THAT HAS STOPPED RECEIVING GROWTH SIGNALS C. A cell with the sudden loss of function of mitochondria D. A large swollen cell with a distended nucleus
B. A CELL THAT HAS STOPPED RECEIVING GROWTH SIGNALS
Mediator of inflammatory & immune reactions
CYTOKINES, INTERFERONS, & COMPLEMENT PROTEINS that function as mediators of inflammatory & immune reaction can also injure cells. These mediators are important for eliminating infectious agents often kill the body's normal cells with the pathogen cells
exogenous toxins
Causes of cell injury Get into the body from the outside (Microbes, Chemicals, Overdose)
complement proteins
Complement proteins are proteins that lyse the cell wall of an antigen. They are part of the nonspecific defense mechanisms of the immune system.
1-1 Which of the following accounts for differences in cells in a human body? A. Diffrences in chromatin B. Diffrences in chromosomes C. Differential content of DNA D. DIFFERENTIAL EXPRESSION OF GENES
D. DIFFERENTIAL EXPRESSION OF GENES
1-6 Which of the following is NOT associated with reversible cellular injury? A. cellular swelling B. decreased energy production C. increased autophagy D. INCREASED PROTEIN SYNTHESIS
D. INCREASED PROTEIN SYNTHESIS
1-9 Which of the following best describes the type of necrosis very soft organs, such as the brain, typically undergo? A. Caseous necrosis B. Coagulative necrosis C. Fat necrosis D. LIQUEFACTIVE NECROSIS
D. LIQUEFACTIVE NECROSIS
1-5 Cell A secretes substance 1. Substance 1 is taken up 2 cells away by cell B, which then responds by secreting substance 2. This interaction is best described as which of the following? A. Autocrine B. Endocrine C. Exocrine D. PARACRINE
D. PARACRINE
1-7 A cell is subject to hypoxic conditions for 20 minutes then observed under the microscope. The nucleus has become shrunken, with marked condensation of the chromatin. This nuclear change is best described as which of the following? A. Autophagy B. Karyolysis C. Karyorrhexis D. PYKNOSIS
D. PYKNOSIS
1-4 A new cell line is developed that completely lacks a smooth ER. Which of the following functions would these cells be incapable of performing? A. Degrading endocytosed materials B. Maintaining cellular shape C. Making new proteins D. SYNTHESIZING STEROID HORMONES
D. SYNTHESIZING STEROID HORMONES
Lipid accumulation
Fatty change - Fat vacuoles in cells. Most often seen in the liver (single major organ involved in fat metabolism) but can occur elsewhere. Mainly alcohol abuse but also protein malnutrition, diabetes mellitus and obesity. In heart - prolonged moderate hypoxia leads to fat accumulation - tiger effect because it's striped.
Heterophagosomes
Fusion of a lysosomes with phagosomes containing foreign materials.
cytokines
Hormone-like chemicals facilitating communication between brain and immune system.
Direct toxins
Inactivate cytoplasmic enzymes by disrupting sulfhydryl (S_S) groups that hold the polypeptide chain of the enzymes in their active state. EXAMPLE: heavy metals (mercury)
Necrosis vs. Apoptosis
Necrosis: bad, damage to nearby cells caused by lysis Apoptosis: good; for normal functioning of cell. Cell shrinkage, caspase activation,
Lipofuscin
brown lipid rich pigment
Metastatic calcification
calcification occurs in hypercalcemia Example: seen in metabolic conditions such as hyperparathyroidism & vitamin D toxicity & usually involves kidneys
Dystrophic calcification
calcification of dying and dead tissues that occurs as a reaction to tissue injury; necrosis is one example Example: atherosclerotic arteries, damaged heart valves, necrotic tumors
neural stimulation
can give a similar high level of cell function integration as endocrine stimulation the ultimate coordinators of body functions are the central & autonomic nervous systems
pathologic apoptosis
can have endogenous or exogenous cause Example: muscular dystrophy has skeletal muscle that laks specific proteins & thus undergo apoptosis Example: transplanted organs may be attacked by host's immune cells
Mytosis
cell division
point of no return for a cell
cell is unable to be repaired & will die. EXAMPLE: a muscle that has exceeded its ability to stretch & return
Metaplasia
cell type is changed to a different cell type
Irreversible cell injury
cells exposed to heavy doses of toxins, anoxia, severe or prolonged hypoxia, or other overwhelming insults cannot recover. Irreversible cell injury involves more insidious agents such as viruses, immunological responses, or genetic disadvantages.
undifferentiated cells
cells that have not become specialized yet
steatosis
characterized by accumulations of fat within the liver seen in chronic alcohol abuse and diabetes melitus that usually does not cause liver damage
Liquefactive Necrosis
characterized by dissolution of tissue, which becomes soft & diffluent. (tissue becomes soft & mushy) Most often seen in the brain. cells lose contours & become "liquified"( transformed into semifluid mush) coagulative necrosis may liquify but usually leukocytes remove the dead cells & using lytic enzymes transform the solid tissue into viscous yellow fluid of dead cells and leukocytes - "pus"
anthracosis
coal dust accumulates in the lungs
suicide genes
control apoptosis and tell the cell to kill itself if something goes wrong
autolysis
death of cells in a dead organism is due to cessation of heartbeat or respiration
gangrene
death of tissue caused by loss of blood supply followed by bacterial invasion
atrophy
decrease in size of a cell, tissue, organ or the entire body
intermediate filament proteins of muscle cells contain
desmin
differentiated cells
differentiation expression of genes allows cells to perform seperate functions from other cells
indirect toxins
example: of carbon tetrachloride (CCI4) a component of metal cleaning solution when ingested it is metabolized to carbon trichloride (CCI3) which acts as a toxic free radical, damaging cell membranes
necrosis
exogenously induced localized death of cells or tissues in living organisms caused by anoxia or toxins with typical nuclear changes (pyknosis, karyorrhexis & karyolysis), rupture of cell membrane & loss of cellular respiration.
primary lysosomes
fuse with absorptive vesicles (phagocytosis/pinocytosis) to form a secondary lysosome called a heterophagosome
Hereditary Hemochromatosis
genetic disorder of iron absorption in the liver
intermediate filament proteins of glial cells contain
glial acidic fibrillary protein (GAFP)
oligominerals
include magnesium, zinc, copper, & selenium, are needed in minute amounts but are essential for the function of many enzymes.
hypertrophy
increase in muscle size (heart muscle, skeletal muscle (body builder))
neolipogenesis
increased fat formation from glucose, amino acids and alcohol
physiologic apoptosis
involved in formation of many body parts. Example: formation of fingers & toes by removing tissue of digital primordia. If not apoptosis takes place will have SYNDACTYLY-fused digits
Endocrine stimulation
involves the use of hormones released in the blood Since this type of stimulation involves several distinct organs, it is considered a higher form of cell function integration EXAMPLE: Insulin produced by the beta cells in the pancreatic islets affect the liver, muscle fat cells & other areas
intermediate filament proteins of epithelial cells contain
keratins
Paracrine stimulation
mediators are released from one cell and taken up by another EXAMPLE: in the stomach, gastrin is released from enteroendocrine G cells which then stimulate the neighboring chief cells to release hydrochloric acid
Reversible cell injury
mild short lived cessation of injury results in the return of the cell to its original steady state. Reversible cell injury is usually the result of the beginning stages of lack of oxygen, also known as hypoxia, or ischemia, the lack of blood flow to cells
cytoplasmic organelles
mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes
Cytoskeleton
network of protein filaments within some cells that helps the cell maintain its shape and is involved in many forms of cell movement
intermediate filament proteins of neural cells contain
neurofilament proteins
pathologic atrophy
occurs as a result of decreases in workload, pressure, use, blood supply, nutrition, hormonal stimulation, and nervous stimulation
Hemociderosis
of the liver develops in people who have received many blood transfusions & in those suffering from hemolytic anemia. Also a constant feature of a genetic disorder of iron absorption from food which is called HEREDITARY HEMOCHROMOTOSIS.
Phagocytosis
process in which extensions of cytoplasm surround and engulf large particles and take them into the cell
Apoptosis
programmed cell death involving a cascade of specific cellular events leading to death and destruction of the cell (active form of cell death)
Proteosome
protein complexes that destroy the porteins bound to a ubiquitin to get rid of deformed or proteins no longer needed
Ribosomes function
protein synthesis
Interferons
proteins (cytokines) secreted by T cells and other cells to aid and regulate the immune response
autophagosome
secondary lysosomes that digests the cell's own organelles
plasma membrane
separates cytoplasm from exracellular fluid
Essential minerals for maintaining homeostasis
sodium, chloride, potassium, calcium, & iron
Enzymatic fat necrosis
special form of liquefactive necrosis caused by lipolytic enzymes, only seen in fat tissue & usually around the pancreas. Pancreatic enzymes released into fat tissue & fat degraded to glycerol & free fatty acids Free fatty acids bind with calcium to form calcium soaps so the tissue appears as liquidized fat with specks of scattered calcium soaps
Golgi apparatus
stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum
Hyperplasia
the enlargement of an organ or tissue because of an abnormal increase in the number of cells in the tissues
Coagulative necrosis
the most common form of necrosis. marked by rapid inactivation of cytoplasmic hydrolytic enzymes which prevents tissue lysis & tissue retain original form & texture. This type of necrosis typically involves solid internal organs (heart, liver, kidneys) & is often caused by anoxia (Myocardial infarct)
Neoplasia
the new and abnormal development of cells that may be benign or malignant
Homeostasis
the state of balance between opposing pressures in and around a cell or tissue.
Oxygen radicals
these toxic compounds are formed in tissues as a result of oxygen activated by ionized iron, or by chemical reactions that produce: hydrogen peroxide (H2O2) superoxide (o2-) hydroxl radical (OH)
Autocrine stimulation
this stimulation is SELF - STIMULATION where the cell secretion effects not only another cell but also the cell it was secreted from this is because the secretory cell has surface receptors for their own secretion EXAMPLE: T lymphocytes which can stimulate the growth of fibroblasts but also act as their own growth factors
Why does the heart become enlarged with hypertension
to counteract the increase in outflow pressure in the heart. (enlargement of individual cells)
caseous necrosis
typically found in TB patients (Tuberculosis) but can be found elsewhere such as Histoplasmosis (fungal infection). Limited liquefaction where the center of the tuberous granuloma becomes necrotic & breaks apart. The tissue is "cheesy" with a yellow-white color.
intermediate filament proteins of mesenchymal cells contain
vimentin
what does it mean if a cell is in a steady state?
when a cell & its environment are in equilibrium, the cells are said to be in a STEADY STATE (homeostasis)
Hydropic change/Cellular swelling
when a cell swells do to water flowing into the cytoplasm what do we call it?
endogenous toxins
are those produced by the body as a byproduct of biochemical processes, and may tend to accumulate in the joints or various muscle groups heavy metals: mercury
Carcinomas
are tumors of epithelial origin, express keratins
Sarcomas
are tumors of mesenchymal cells (connective tissue) express vimentin
1-3 Protein X is needed to help maintain 2 other proteins, both of which only exist in the cytoplasm of the cell. where is protein X most likely synthesized? A. FREE RIBOSOME B. Nucleus C. Rough ER D. Smooth ER
A. FREE RIBOSOME
similarities & differences of necrosis & apoptosis
Apoptosis- usually affects single cells unlike Necrosis which affects groups of cells
Hyaloplasm
Amorphous matrix: ground substance of the cytoplasm consisting mostly of water but also minerals, proteins, lipids & carbohydrates
1-8 A 65-year-old male has had uncontrolled hypertension for 30 years. As a result, there are twice as many fibroblast cells (all of normal size) in his aorta than 30 years ago. This is best described as which of the following? A. Dysplasia B. HYPERPLASIA C. Hypertrophy D. Metaplasia
B. HYPERPLASIA
1-2 Which of the following is the primary purpose of mitochondria? A. Maintenance of cell shape B. Modification of proteins C. PRODUCTION OF ENERGY D. Replication of cellular structures
C. PRODUCTION OF ENERGY
Autolysis
Death of cells in a dead organism is due to cessation of heartbeat or respiration. self-destruction of cells; decomposition of all tissues by enzymes of their own formation without microbial assistance
intracellular accumulations
Excess accumulations of substances in cells may lead to cellular injury due to toxicity, immune response, and/or taking up cellular space
Hyperoxia
Excess oxygen or higher than normal partial pressure of oxygen
Hypoxia
Low oxygen saturation of the body, not enough oxygen in the blood
enzymatic scavenger systems
The free radical scavenger is often referred to as an antioxidant. They are generally found in certain foods, primarily dark colored fruits and vegetables like blueberries. These scavengers work by preventing the oxidation process that is required in order for electrons to be passed from one cell to another.
Thymus
The thymus grows throughout childhood until the onset of puberty. InnerBody states that that the immune system creates most of its T cells during childhood. The immune system requires very few new T cells after puberty. Because the body no longer has the same need for new T cells, the thymus gland is no longer needed to the same extent.
Hemociderin
a brown pigment derived from hemolyzed blood.
reversible change
a change that can be reversed to get back the original materials
syndactyly
a condition wherein two or more digits are fused together
Dysplasia
abnormal development or growth of cells, tissues, or organs (disordered arrangement of cells & nuclear atypia)
Hemosiderosis
abnormal increase of iron in blood brown pigment in blood from hemolyzed blood
anoxia
absence of oxygen
