cellular regulation and fundamentals Flashcards
cellular regulation
functions carried out within a cell to maintain homeostasis
atrophy
decrease in size and function
hypertrophy
increase in size and functional capacity
hyperplasia
increase in number of cells, increase in organ size
dysplasia
deranged cell growth, change in size, shape and uniformity
metaplasia
replacement of one cell type with another
TIPS
toxins, infections, physical injury, serum deficit injury
Toxins
external/internal
physical injury
mechanical, chemical, thermal,
serum deficit injury
nutrition, oxygenation, hydration
hypoxic injury
most common cause of cellular injury
- reduced oxygen in air
- loss/decreased efficacy of hemoglobin
- decreased production of RBC
- disease of respiratory/cardiovascular
- poisoning of oxidative enzymes
ischemia
most common cause of hypoxia
ischemia-reperfusion injury
additional injury caused by restoration of blood flow and oxygen
Mechanisms of ischemia-reperfusion injury
- oxidative stress
- increased intracellular calcium
- inflamation
- complement activation
- anoxia
cellular responses to ischemia-reperfusion injury
- decrease in ATP, sodium-potassium pump and sodium calcium pump exchange failure
- cell swelling
- vacuolation
free radicals and reactive oxygen species (ROS)
electrically uncharged atom has an unpaired electron damages: -lipid peroxidation -alteration of proteins -alteration of DNA -mitochondria
lipid peroxidation
membrane damage
alteration of proteins
breakdown/misfolding
alteration of DNA
mutations
chemical injury - xenobiotics
examples
- carbon tetrachloride
- lead
- carbon monoxide
- ethanol
- mercury
- social/street drugs
chemical injury - medications
over the counter and prescribed direct damage: chemical and medications injure cells -> combine with critical molecular substances -chemotehrapy -drug abuse
chemical injury - hypersensitivity reactions
range
mild skin rash to immune-mediated organ failure
blunt force injury
mechanical force to the body
- tearing, shearing, or crushing of tissue
contusions, lacerations and fractures
sharp force injury
well defined traumatic separation of tissues
- incised
- stab
- puncture
- chopping
gunshot wound
penetrating or perforating
- entrance
- exit
- range of fire
asphyxial injuries
failure of cells to receive/use oxygen
types of asphyxial injuries
suffocation
strangulation
chemical
drowning
suffocation
choking asphyxiation
strangulation
hanging, ligature, manual
chemical
cyanide and hydrogen sulfide
infectious injury
caused by pathogen disease producing potential -invasion and destruction -toxin production -production of hypersensitivity reaction
immune and inflammatory substances
histamine, antibodies, lymphokines, complement and proteases
manifestations of cellular injury
cellular accumulations pigments calcium urate systemic manifestations
Manifestations of Cellular Injury
cellular accumulations
water
lipids and carbohydrates
glycogen
proteins
Manifestations of Cellular Injury
pigments
melanin
hemoproteins
bilirubin
Manifestations of Cellular Injury
calcium
dystrophic:
dying and dead tissues
metastatic:
undamaged normal tissues
cellular death
significant external stimuli
irreversible and cells die
necrosis and apoptosis
Necrosis cell size nucleus plasma membrane cell contents adjacent inflammation physiological/pathological role
enlarged/swelling pyknosis->karyorrhexis->karyolysis disrupted enzymatic digestion (leak out of cell) frequent invariably pathological
Apoptosis cell size nucleus plasma membrane cell contents adjacent inflammation physiological/pathological role
reduced (shrink) fragmentation into nucleosome-size intact; structure altered intact; released in bodies no physiological - get rid of unwanted cells
coagulative necrosis
kidneys, heart and adrenal glands
protein denaturation
liquefactive necrosis
neurons and glial cells of brain
hydrolytic enzymes
bacterial infection
caseous necrosis
tuberculosis pulmonary infection
combo of coagulative and liquefactive
fat necrosis
breast, pancreas, other abdominal organs
action of lipases
gangernous necrosis
death of tissue from severe hypoxic injury
dry vs wet
gas gangrene - clostridium
autophagy
self destruct (survival mechanism) cell contents digested by lysosome
cellular aging
atrophy, decreased function, loss of cells
tissue and systemic aging
progressive stiffness and rigidity
sarcopenia
frailty (aging)
mobility, balance, muscle strength, motor activity, cognition, nutrition, endurance, falls, fracture, bone density
somatic death
death of the entire person
algor mortis
reduction of body temp
livor mortis
purple discoloration
rigor mortis
muscle stiffening
