Cell Injury & Adaptation Flashcards
hypertrophy
increase in the size of an organ w/o an increase in cell number
can hypertrophy and hyperplasia occur together?
yes- this is typically the case
when does pure hypertrophy occur?
only in skeletal and cardiac muscle
what can be a side effect of hypertrophy?
increased distance to source of nutrients
what does this represent?
hypertrophy of cardiac muscle
hyperplasia
the increase in size of a tissue or organ due to an increased number of cells
examples of hyperplasias that are physiologic:
-erythroid bone marrow hyperplasia at high altitude
-cyclic enlargement of the endometrium and breast during the menstrual cycles
-regrowth of liver parenchyma after surgical excision is compensatory
examples of hyperplasias that are pathologic:
epithelial hyperplasia caused by HPV
ID
epithelial hyperplasisa: papilloma
ID
endothelial hyperplasia: pyogenic granuloma
ID
fibrous hyperplasia: fibroma
ID
fibrous hyperplasia: epulis fissuratum
*caused by ill-fitting denture
ID
epithelial & fibrous hyperplasia: inflammatory papillary hyperplasia (of the palate)
ID
osseous hyperplasia: sub-pontic osseous hyperplasia
ID
osseous hyperplasia: exostoses
ID
gingival enlargement (hyperplasia)
ID
gingival enlargement (hyperplasia)
examples of meds that can cause gingival enlargement:
-Procardia (calcium channel blockers)
-Cyclosporin (immunosuppressant)
-Dilantin (anti-seizure med)
examples of gingival enlargement (hyperplasia):
-inflammatory hyperplasia
-drug-induced enlargement
-leukemic infiltrates
-amyloid infiltration
-Klippel-Trenaunay-Weber syndrome
-juvenile hyaline fibromatosis
-Cowden syndrome
-Wegener granulomatosis
ID
condylar hyperplasia
ID
condylar hyperplasia
ID
condylar hyperplasia
ID
condylar hyperplasia
ID
hyperplastic dental follicle
*radiolucency around tooth
*would need biopsy to diagnose
ID
gynecomastia- hyperplasia of male breast
atrophy
reduction in size of cells, tissues, or organs
examples of pathologic atrophy:
-atrophy of skeletal muscle following denervation
-atrophy of the brain due to ischemia
examples of physiologic atrophy:
-atrophy of the uterus after pregnancy
-involution of the thymus in early adult life
pathologic atrophy may result from:
-disuse
-denervation
-lack of trophic hormones
-ischemia (reduction in blood supply)
-malnutrition
-idiopathic (Parry-Romberg syndrome)
ID
atrophy
ID
atrophy
diseases that can cause brain atrophy:
-atherosclerotic disease
-alzheimer disease
what is this?
progressive hemifacial atrophy (Pary Romberg Syndrome)
*always unilateral
*ideopathic
*no intervention until atrophy has run its course
metaplasia
replacement of one mature cell type by another one
metaplasia represents a change to a _____ cell type
tougher
is metaplasia reversible?
generally yes- tissue can revert to its normal state after irritant is removed
what happens if an irritant is persistant in a tissue?
metaplasia may progress to dysplasia and then to frank neoplasia
what happens to smokers bronchial epithelium?
stratified columnar epithelium —> squamous epithelium
what happens to gastric epithelium with gastric reflux?
Barrett esophagus
which esophagus is normal?
left
necrotizing sialometaplasia
-occurs on the palate
-can be uni or bilateral (unilateral harder to detect)
-metaplasia into squamous tissue in the connective tissue with signs of necrosis
-white border
what are examples of adaptive cell responses to non-lethal injury?
-hyperplasia
-hypertrophy
-atrophy
-metaplasia
what are examples of non-adaptive cell responses to non-lethal injury?
-agenesis
-aplasia
-hypoplasia
agenesis
failure to develop
*typically not compatible with life
what is this an example of?
tooth agenesis
-retained primary molar –> agenesis of permanent premolar
what is this an example of?
tooth agenesis
*no history of extraction
aplasia/hypoplasia
the incomplete development of an organ
*organ never reaches normal size
what is Treacher Collins syndrome?
mandibulo-facial dysplasia
what is Pierre-Robin syndrome?
aplasia/hypoplasia of the mandible
ID
aplasia/hypoplasia
-Pierre-Robin syndrome
ID
aplasia/hypoplasia
*radiation treatment causes hypoplastic roots
ID
aplasia/hypoplasia- regional odontodysplasia
*small & under calcified teeth (ghost teeth)
dysplasia
literally means abnormal formation
*altered growth status
-used in many contexts (we mainly use it in terms of pre-malignant)
ID
epithelial dysplasia
ID
ectodermal dysplasia
ectodermal dysplasia
tissues derived from ectoderm do not develop correctly (teeth, hair, etc.)
ID
fibro-osseous dysplasia
*NOT pre-malignant
ID
fibrous dysplasia
-unilateral enlargement of jaw bone (maxilla or mandible)
*NOT pre-malignant
ID
fibrous dysplasia
ID
fibrous dysplasia
ID
dentin dysplasia, type I
example of reversible changes:
fatty change- liver
examples of irreversible changes:
-necrosis
-apoptosis
which type of cell death is messy?
necrosis
which type of cell death is precise?
apoptosis
-usually affects one cell at a time
nuclear changes that signal cell death in necrosis:
-pyknosis
-karyorrhexis
-karyolysis
pyknosis
small, dark and shrunken nucleus
karryorrhexis
nuclear fragmentation
karyolysis
dissolution of the nucleus
what tells you how the cell has died?
the cytoplasm
coagulative necrosis
typically seen in hypoxic injury (myocardial infarct)
liquefactive necrosis
typically seen in bacterial infections and cerebral infarct (stroke)
caseous necrosis
necrotic tissue is converted into a cheesy mass (tuberculosis)
fat necrosis
characteristically seen in acute pancreatitis
what pattern of necrosis?
coagulative necrosis
what pattern of necrosis?
liquefactive necrosis
what pattern of necrosis?
caseous necrosis
what pattern of necrosis?
fat necrosis
what pattern of necrosis?
coagulative necrosis
what pattern of necrosis?
coagulative necrosis
what pattern of necrosis?
liquefactive necrosis (cerebral infarct)
what pattern of necrosis?
caseous necrosis
what type of cell death is occurring here?
apoptosis
apoptosis
programmed cell death that occurs through activation of an internal suicide program
-selectively eliminates unwanted cells with minimal disturbance to the surrounding cells
what enzymes manage apoptosis?
CASPASES
what keeps apoptosis neat?
the plasma membrane remains intact, but its structure is altered so that it becomes a target for phagocytosis
what prevents apoptosis from eliciting an inflammatory reaction?
the dead cell is rapidly cleared before its contents have leaked out
physiologic examples of apoptosis:
-programmed cell destruction of cells during embryogenesis
-hormone-dependent involution of tissues in the adult
-deletion of potentially harmful self-reactive lymphocytes
-cell death induced by cytotoxic T-cells (virally infected or neoplastic cells)
pathologic examples of apoptosis:
-if DNA repair mechanisms cant cope with damage, the cell kills itself by apoptosis
-cell death in certain viral infections (HepC)
-pathologic atrophy in organs after obstruction
-cell death in tumors
exogenous pigments:
-carbon (anthracosis)
-tatooing (skin and mucosal tattoos; can be intentional or unintentional like amalgam tattoos)
endogenous pigments:
-lipofuscin (aging pigment)
-melanin (formed in melanocytes)
-hemosiderin (hemoglobin-derived)
-bilirubin (derived from RBCs)
pathologic calcification
the abnormal deposition of calcium salts in tissue
dystrophic calcification
occurs in nonviable or dying tissues in the presence of NORMAL serum calcium levels
metastatic calcification
occurs in viable tissues and is associated with hypercalcemia
-mostly in bile and liver tissues
