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