Cellular Adaptation and Repair
which type of atrophy is caused by a loss of blood supply (ex: brain or heart atrophy due to atherosclerosis)
ischemic atrophy
surface epithelial cells, crypt cells of gut mucosa, seminiferous germ cells, hematopoietic stem cells, and endometrium are example of what cell type
labile cells
which cells normally divide actively to replace continually lost cells
labile cells
cells of the body are divided into what 3 groups according to their regenerative capacity
labile, stable, permanent
what type of skin wound is a tear
laceration
what property of collagen decreases the size of a scar in stage 4 of scar formation
contraction
the pathogenesis of hypertrophy involves an increased amount of _______ and increased number of cytoplasmic __________ (ex: myofilaments in muscle fibers, synthetic apparatus in secretory cells)
cytoplasm, organelles
the pathogenesis of atrophy involves a decrease in the amount of ________ and number of cytoplasmic ___________ and increased number of ____________
cytoplasm, organelles, autophagic vacuoles
in atrophy resistant debris accumulates in the cytoplasm...an example of this is
lipofuscin
a foreign body, necrotic tissue, extensive blood, infection, abscess formation, abnormal blood supply, ischemia, and impaired venous drainage are examples of what type of defective wound healing
local factors
decrease in secretion of hormones or high doses of corticosteroids are examples of what type of atrophy
loss of endocrine stimulation
the mechanism through which there is an adaptive replacement of cells that are sensitive to stress by more resistant ones (reversible)
metaplasia
the replacement of one adult mature cell type by another cell type is known as
metaplasia
deposition of calcium salts in normal tissue due to hypercalcemia is known as (common in blood vessels, kidneys, lungs, and stomach)
metastatic calcification
vitamin D intoxication, hyperparathyroidism, hyperthyroidism, and bone tumors are common causes of
metastatic calcification
healing by 2nd intention is similar to first intention but it needs ________ time, _______ granulation tissue, and forms a ________ scar
more, more, bigger
the first step of scar formation is preparation of the area by removal of
necrotic tissue
which type of cellular adaption may occur without known stimulus, is irreversible, and has abnormal cells in malignant cases
neoplasia
which type of atrophy is caused by lack of nutrition
nutritional atrophy
replacement of lost tissue by scar formation is which type of repair
organization
what type of metaplasia occurs in scars and areas of muscle trauma
osseous metaplasia
what are the 2 types of metaplasia that occur in mesenchymal tissue
osseous metaplasia and calcium deposition
hormonal stimulation like in acromegaly due to the increased secretion of growth hormone is which type of hypertrophy
pathological
increased functional demand like in the left ventricle of hypertensive patients is which type of hypertrophy
pathological
a gross appearance of fine white (or yellow) granules or clumps in soft tissues is known as
pathological calcification
a microscopic appearance of basophilic amorphous granular material and lamellate appearance of several layers (psammoma bodies) is seen in
pathological calcification
psammoma bodies are associated with what cellular adaptation
pathological calcification
endometrium growth due to increased estrogen stimulation and adrenal gland growth due to increased secretion of ACTH are examples of
pathological hyperplasia
what cell type has no capacity for mitotic division in post-natal life (ex: neurons and myocardial cells)
permanent cells
hormonal stimulation like in the uterine muscles during pregnancy is which type of hypertrophy
physiologic
increased functional demand like in striated muscles of a muscle builder is which type of hypertrophy
physiologic
growth of liver cells following a partial hepatectomy is an example of
physiologic compensatory hyperplasia
growth of the epithelium of the female breast at puberty is an example of
physiologic hormonal hyperplasia
atrophy of the umbilical vessels and ductus arteriosus after birth, thymus after puberty, and ovaries, uterus and breast after menopause are examples of what type of atrophy
physiological atrophy
which growth factor involved in wound healing causes proliferation of fibroblasts
platelet-derived growth factor (PDGF)
which type of atrophy occurs in the skin and subcutaneous tissue over the sacrum in patients with prolonged bed rest (bed sores)
pressure atrophy
healing by first intention is also known as
primary union
during the growth of highly vascularized connective tissue in scar formation, fibroblasts are stimulated to __________ and ___________ collagen, elastic and reticular fibers, extracellular matrix, formation of actin and myosin, and filaments
proliferate, secrete
stable cells heal with ______ or ________
regeneration (if enough viable cells remain intact) or scar formation
labile cells heal with ________ only
regeneration (resolution)
replacement of injured cells by new parenchymal cells of the same type by division of adjacent ones is what type of repair
regeneration (resolution)
what are the 2 types of repair
regeneration (resolution) and organization
injury to tissue with permanent cells is always followed by ___________ (no regeneration is possible, irreversible)
scar formation
permanent cells heal with _______ only
scar formation
repair by connective tissue is also known as
scar formation
in healing by first intention, cells of the dermis heal by
scar formation (initially pink but turns white)
healing by second intention is also known as
secondary union
what type of metaplasia occurs in atheromas and bronchial cartilage
calcium deposition
the pathological features of dysplasia are: 1: increased rate of __________ (numerous mitotic figures) 2: loss of _________ of cells 3: loss of epithelial ________ 4: increase in size and chromatin content of the _________
cellular multiplication, uniformity, polarity, nucleus
in healing by first intention the small gap in the dermis and epidermis filled with _______________ forming a scab that seals the wound opening
clotted blood
the second step of scar formation is growth of _________________ connective tissue from the surrounding healthy tissue
highly vascularized
what are the 3 types of physiological hyperplasia
hormonal, compensatory, antigenic
when corticosteroids are applied topically leading to skin atrophy it is known as
hormone induced atrophy
the adaptive response to increased functional demand of tissue made of labile or stable cells (can divide) is known as
hyperplasia
the increased size of an organ or tissue as a result of an increased number of component cells is known as
hyperplasia
what type of cellular adaptation has a known stimulus, is reversible, and the cells look normal
hyperplasia
the increased size of a tissue or organ due to increased size of individual cells is known as
hypertrophy
what is the adaptive response to an increased functional demand of tissues made up of permanent cells (cannot divide)
hypertrophy
what 2 modes of cellular adaptation occur together in the myometrium during pregnancy due to estrogen stimulation
hypertrophy and hyperplasia
what type of skin wound is a cut
incision
skin wound types where both the epidermis and dermis are involved but healing is rapid (1st intention) and there is no infection, no foreign material, and minimal tissue loss
incision (cut) and laceration (tear)
during scar formation, over time collagen content progressively ______ whereas capillaries and fibroblasts ________
increases, decrease
stable cells remain in the ____________ phase for long periods while retaining their capacity to enter the mitotic cycle when needed
intermitotic
tensile strength of a young scar is first ____ % that of normal skin, increases to ____ % after 1 month and to _____ % after 4 months
10, 50, 80
clean wounds (surgical incisions) with edges in close apposition, non-infected, and having minimal tissue loss are healed by
1st intention (primary union)
in healing by first intention the cells of the basal layer at the edges of the wound begin to divide providing a continuity of the epidermis in _________ hours
24-48
wounds characterized by extensive necrosis, secondary infection, gaping, and inflammation heal by
2nd intention (secondary union)
which growth factors involved in wound healing are chemotactic for fibroblasts and cause increased collagen synthesis (fibrogenic cytokines)
IL-1 and TNF
the adaptive response to a decrease in the body's requirement for the function of a certain cell or tissue
atrophy
decrease in the size of a cell by loss of cell substance leading to decreased metabolic and functional activity
atrophy of cell
decrease in the size of an organ due to either decrease in the size or number of component cells
atrophy of organ
what type of skin wound is a scrape
abrasion
skin wound type with removal of the superficial part of epidermis that maintains an intact basal cell layer (labile cells) capable of regenerating the epithelium without scarring
abrasion (scrape)
high doses of corticosteroids lead to atrophy of which gland
adrenal
brain atrophy in senile dementia is an example of which type of atrophy
aging atrophy
bed sores (commonly caused by pressure atrophy) are also known as
decubitus ulcers
which type of atrophy is caused by a loss of innervation
denervation atrophy
what type of defective wound healing is caused by decreased blood supply (atherosclerosis) and increased susceptibility to infection (due to glucose level in blood)
diabetes mellitus
which type of atrophy is caused by decreased function (skeletal muscle and bones in immobilized fractured limb)
disuse atrophy
prolonged irritation, prolonged inflammation, and carcinogenics are common causes of
dysplasia
what is an abnormality in maturation and differentiation of epithelium (premalignant condition)
dysplasia
atherosclerosis, necrotic tissue, and heart valves in rheumatic fever are examples of
dystrophic calcification
deposition of calcium salts in dead or dying tissue (normal serum calcium level) is
dystrophic calcification
what is the inherited disease involving a deficiency of enzymes involved in collagen synthesis leading to abnormal collagen, impaired wound healing, increased elasticity of skin (rubber man), easy bruisability, and hyperextensibility of joints
ehlers-danlos syndrome
which growth factor involved in wound healing causes proliferation of epidermal cells and fibroblasts
epidermal growth factor (EGF)
which cause of defective wound healing results in nodular masses of collagen (keloids) at the site of skin injury, common in blacks, familial tendency
excessive collagen production
what type of defective wound healing interferes with phagocytosis, decreases arachidonic acid metabolites (phospholipase) , and impairs collagen synthesis
excessive levels of corticosteroids
deficiency of protein, vitamin C, or zinc causes what type of defective wound healing
failure of synthesis of collagen fibers
ehlers-danlos syndrome is an example of what type of defective wound healing
failure of synthesis of collagen fibers
during the growth of highly vascularized connective tissue in scar formation, what promotes angiogenesis and is chemotactic to fibroblasts
fibronectin
which growth factor involved in wound healing is used for angiogenesis (new vessel formation) and is chemotactic to fibroblasts
fibronectin
what is it called when there is a replacement of the normal stratified squamous epithelium of the esophagus with mucous-secreting epithelium in reflux esophagitis (hiatal hernia)
glandular metaplasia
in stage 3 of scar formation, the granulation tissue is _________________________ because of numerous capillaries
soft, fleshy, and deep red
during the growth of highly vascularized connective tissue in scar formation, endothelial cells proliferate as ___________ and become canalized into new capillaries
solid buds
what is it called when there is a replacement of the normal columnar ciliated epithelium of the respiratory tract with stratified squamous epithelium (smokers)
squamous metaplasia
parenchymal cells of solid organs (liver, lung, alveoli, renal tubules, pancreas) and mesenchymal cells (osteoblast, chondrocytes, fibroblast, endothelial cells) are examples of what cell type
stable cells
which cell type have a long life span and very slow rates of division
stable cells
in scar formation, the increased formation and changing type of collagen (3 to 1) causes
strengthening
which growth factor involved in wound healing stimulates fibroblast mitosis
thrombin
decreased secretion of pituitary trophic hormones leads to atrophy of which glands
thyroid, adrenal, and gonads
skin wound type involving loss of large areas of epidermis and necrosis of underlying dermis where a phase of inflammation precedes the repair (2nd intention)
wounds with epidermal effect
what type of skin wound are burns and crush injuries
wounds with epidermal effect