Patho Ch. 4 Altered Cellular and Tissue Biology

Physiologic

related to healthy, normal functioning organism

Pathologic

related to something caused by disease, something is wrong or abnormal

atrophy

decrease in cell size

hypertrophy

increase in cell size

hyperplasia

increase in number of cells due to increase cell division rate

dysplasia

abnormal changes in size, shape, and organization of mature cells

metaplasia

reversible replacement of one mature cell type with another

metaplasia associated with

tissue damage, repair, and regeneration

dysplasia found in

cervix, endometrium, GI tract, and respiratory tract

hypoxia

insufficient oxygen in cells, most common cause of cellular injury

ischemia

decreased supply of blood, most common cause of hypoxia

anoxia

total lack of oxygen

ischemia-reperfusion injury

caused by restoration of blood flow and oxygen to the ischemic tissues

ischemic injury causes

anaerobic metabolism and energy depletion

reperfusion injury causes

release of reactive oxygen species (free radicals) and inflammation

oxidative stress

injury caused by reactive oxygen species (ROS)

Reactive oxygen species (ROS)

oxygen containing reactive molecules

free radical

a type of ROS, unstable molecule that can form damaging bonds with cell membrane components

free radical generated by

chemical or radiation injury, ischemia-perfusion injury, cellular aging, or microbial destruction by phagocytes

antioxidants

prevent formation of free radicals, work against the ROS

xenobiotics

have toxic, mutagenic, carcinogenic properties, also hepatotoxic

mutagenic

prone to causing mutations

carcinogenic

prone to causing cancer

sources of xenobiotics

cleaning supplies, insect sprays, and diet

Asphyxiation

lack of oxygen

suffocation

lack of oxygen in environment or blocked airway

strangulation

compression of blood vessels and airways caused by external pressure

chemical asphyxiation

prevent oxygen delivery to tissues or block oxygen utilization with chemicals

examples of chemicals used for chemical asphyxiation

carbon monoxide, cyanide, hydrogen sulfide, and methane

drowning

lungs filled with liquid

necrosis

cell death occurring from persistent injury

causes of necrosis

ischemia, toxins, chemical/physical injury (burns), leaked proteases (pancreatitis)

types of necrosis

coagulative, liquefactive, caseous, fatty, and gangrenous

gangrenous necrosis

nonspecific, clinical term often in lower leg, two types are wet and dry

dry necrosis

coagulative necrosis; dry, brown, and black

wet necrosis

necrotizing bacterial infections; tissues cold, swollen, black, and have foul odor, may effect internal organs

gas gangrene

caused by clostridium, usually from deep puncture wounds, progresses rapidly

apoptosis

cellular self destruction, programmed cell death, may be normal or pathologic

somatic death

systemic death of entire body

pallor mortis

skin becomes pale and yellow

algor mortis

decrease in body temperature

rigor mortis

stiffening of muscles

livor mortis

gravity causes blood to settle in dependent tissues causing blue and purple discoloration