Chapter 3 Flashcards
What is proper muscle mass maintained by?
Sufficient levels of insulin and insulin-like-growth factor-1
They both have the ability to stimulate growth and limit protein degradation
Most common cause of hypertrophy of the chamber of the heart
Left ventricular hypertrophy due to hypertension
Compensatory hypertrophy
Enlargement of a remaining organ or tissue after a portion has been surgically removed or becomes inactive.
If one kidney is removed, the remaining kidney enlarges to compensate for the loss.
Dilated Hypertrophy
The hypertrophied cells have a relatively greater increase in length than width
Pressure Overload as occurs with HTN
The hypertrophied cells have greater width than length
Hyperplasia
Increase in the number of cells in an organ or tissue
Happens in tissues with cells that are capable of mitotic division, such as the epidermis, intestinal epithelium, and glandular tissueh
What cells have limited hyperplastic growth
Neurons rarely divide which limits hyperplastic growth
Two common types of physiologic hyperplasia
hormonal and compensatory
eg. Breast and uterine enlargements during pregnancy are examples of physiologic hyperplasia that result from estrogen stimulation
What organ goes through hyperplasia and hypertrophy?
Pregnant uterus as a result of estrogen stimulation
What are most forms of non-physiologic hyperplasia due to?
Excessive hormonal stimulation
eg. excessive estrogen production causes endometrial hyperplasia and abnormal menstrual bleeding. increasing the risk of developing endometrial cancer
eg. Skin warts produced by certain virus such as HPV
Metaplasia
Represents a reversible change in which one adult cell (epithelial or mesenchymal) is replaced by another adult cell type
What usually causes Metaplasia?
Chronic irritation and inflammation
Examples for Metaplasia
Adaptive substitution of stratified squamous epithelial cells for the ciliated columnar epithelial cells in he trachea and large airways.
Cervix undergoes metaplasia dye to the hormonal changes in puberty and chronic irritation
Dysplasia
Characterized by deranged cell growth of a specific tissue that results in cells that vary n size, shape, and organization
Strongly implicated as a precursor for cancer
Myositis
Accumulation of beta-amyloid fragments– skeletal muscle disorder
von Gierke disease
Large amounts of glycogen accumulate in the liver and kidneys because of a deficiency of the enzyme glucose-6-phosphate. Without thus enzyme the glycogen cannot be broken down to form glucose. Leads to an accumulation of glycogen but also a reduction in blood glucose levels
Tay-Sachs Disease
Genetic disorder
Abnormal lipids accumulate in the brain and other tissues, causing motor and mental deterioration beginning at approximately 6 months of age, followed by death at 2-5 years of age.
Lipofuscin
yellow-brown pigment that results from the accumulation of the indigestible residues produced during normal turnover of cell structures.
Increases with age and is sometimes referred to as the wear-and-tear pigment.
More common in the heart, nerve, and liver cells than other tissues and is seen more often in conditions associated with atrophy of an organ
Most common exogenous pigments
Coal dust
Accumulation of carbon dust blackens the lung tissue and may cause serious lung damage
Pathological Calcification
Involves the abnormal tissue deposition of calcium salts, together with smaller amounts of iron, magnesium, and other minerals
Dystrophic calcification
Occurs in dead or dying tissue
Macroscopic deposition of calcium salts in injured tissue. Often visible to the naked eye as deposits range from gritty, sand-like grains to form, hard rock material
Often seen in areas of injury in the aorta and large blood vessels and damaged heart valves.
Metastatic calcification
Occurs in normal tissue
Occurs in normal tissues as a result of increased serum calcium levels (hypercalcemia).
Major cause of hypercalcemia
Hyperparathyroidism
Which tissues are more vulnerable to radiation injury?
Rapidly diving cells of bone marrow and intestine
Side effects of radiation therapy
Radiation Dermatitis is common
Necrosis of the skin
Impaired Wound Healing
Chronic radiation dermatitis
Skin damage produced by UV radiation is thought to be caused by
Reactive Oxygen Species (ROS)
Damage to melanin-producing processes in the skin
Xeoderma Pigmentosum
Genetic disorder
An enzyme needed to repair sunlight-induced DNA damage is lacking
Autosomal recessive disorder is characterized by extreme photosensitivity and an increased risk of skin cancer in sun-exposed skin
A deficiency in ___________ increased lead absorption
Calcium, iron, or zinc
Major targets of lead toxicity
RBC, GI tract, kidneys, and the nervous system
Cardinal sign of lead toxicity
Anemia
Free radicals
Highly reactive chemical species with an unpaired electron in the outer orbit of the molecule. Unstable and highly reactive. May disrupt and damage cells and tissues.
Oxidative Stress
Condition that occurs when the generative reactive oxygen species exceeds the ability of the body to neutralize and eliminate ROS
Can lead to oxidation of cell components, activation of signal transduction pathways, and changes in gene and protein expression. DNA modification and damage can occur.
ALS
Antioxidants
Natural and synthetic molecules that inhibit the reactions of ROS with biological structures or prevent the uncontrolled formation of ROS.
Include enzymatic and nonenzymatic compounds.
Oxygen deprivation for brain cells to cause permanent damage
4-6 minutes of oxygen deprivation
Calcium functions as an important ________ and _________ signal for many cell responses
second messenger and cytosolic signal
Extrinsic Pathway of Apoptosis
Involves the activation of receptors such as tumor necrosis factor receptors and Fas Ligand receptor.
Intrinsic pathway for apoptosis
Activated by conditions such as DNA damage, ROS, hypoxia, decreased ATP levels, cellular senescense, and activation of the p53 protein by DNA damage
How is necrosis different from apoptosis
Causes loss of cell membrane and integrity and enzymatic breakdown of cell parts and triggers the inflammatory process. Necrosis often interferes with cell replacement and tissue regeneration.
Liquefactive necrosis
Occurs when some of the cells die byt their catalytic enzymes are not destroyed.
eg. Softening of the center of an abcess with discahrge of its contents
Coagulation necrosis
Acidosis develops and denatures the enzymatic and structural proteins of the cell.
Characteristic of hypoxic injury and is seen in infarcted areasI
Infarction
Occurs when an artery supplying an organ or part of the body becomes occluded and no other source of blood supply exists
Caseous necrosis
Distinctive form of coagulative necrosis in which the deal cells persist indefinitely.
Most commonly found in the center of tuberculous granulomas or tubercles
Gangrene
Considerable mass of tissue undergoes necrosis.
Dry or moist.D
Dry Gangrene
BEcomes dry and shrinks and its color changes to dark brown or black. Spread is slow. Usually results from interference with the arterial blood supply to a part without interference with venous return and is a form of coagulative necrosis
Wet Gangrene
Area is cold, swollen, and pulseless.
Skin is moist, black, and under tension
Blebs form on the surface, liquefaction occurs, anda foul odor is caused by bacteria action.
No normal line of demarcation between the normal and diseases tissues and the spread of tissue damage is rapid.
Systemic symptoms are sever and death may occur unless the condition can be arrested.
Confined mostly to extremeties.
Dry can convert to wet.
Gas Gangrene
results from infection of devitalized tissues by one of several clostridium bacteria, most commonly clostridium perfringens.
Anaerobic and spore forming organsims are widespread in nature, paticularly in soil.
Prone to occur in trauma and compound fractures in which dirt and debris and embedded. Some speciies have been isolated in the stomach, gallbladder, intestine, vagina, and skin of healthy people.
Bubbles of hydrogen sulfide gas that form in the muscle. Serious and potentially fatal.
ABXare used to treat, and surgery for infected tissue.
