Cellular Adaptations, Injury and Death Flashcards
Is disease an illness
-not necessarily
-illness is a patient’s experience of unhealth
->illness can exist without disease
What is disease
-there are several components
-etiology(cause)
-pathogenesis(development)
-structural alterations(histologic changes)
-functional alteration(pathophysiology)
-signs, symptoms, illness
Who is the father of modern pathology
-rudolf virchow
How is disease defined
-cellular pathology that arise from pertubations in molecules
->which affect cellular function, growth and survival
What are categories of disease
-blood vessels and blood flow
-inflammatory
-infections
-immunologic
-neoplasms
-genetic
-environment
What is a cellular adaptation
-reversible changes in size, number, phenotype, metabolic activity, or functions of cels in response to changes in environment
-changes may be physiological or pathologic
What is hypertrophy
-enlargement of a tissue or organ through an increase in cell size
->eg; left ventricular hypertrophy due to hypertension or aortic stenosis
What is hyperplasia
-enlargement of a tissue or organ through increase in cell number
->some have an a tendency to develop malignancy
-eg; endometrial hyperplasia
->due to unopposed estrogenic stimulation
-eg; nodular prostatic hyperplasia
What is atrophy
-decrease in the size of a tissue or organ due to decrease in cell size and metabolic activity
->eg; cerebral atrophy with age
What is meant by the term metaplasia
-change from one cell type to another
->some are at risk to be malignant
-eg; gastroesaphageal reflux and barrett’’s esophagus
What is the definition of cell injury
-abnormalities in one or more essential cellular components
-changes in mitochondria
->decreased ATP(energy) , increased oxidative stress with incomplete oxidative phosphorylation
-leakage of contents through membranes(intra or extra)
-DNA identifies cell cycle arrest
->apoptosis trigger
Is cell injury recovery possible in sub-lethal
-yes
What are the causes of cell injury
-hypoxia/anoxia/ischemic
-infectious/inflammatory/immunologic
-toxic/metabolic
-chemical agents
-physical agents
-genetic abnormalities
What is necrosis
-accidental cell death
-occurs to a group of cells
-often pathologic
What are the main causes of necrosi
-ischemia
-microbial toxins
-burns, other chemical and physical insults
What happens to cells as a result of necrosis
-cells swell
-cell membranes disrupted
-cellular contents leak out
-cellular explosion, whereas apoptosis is implosion
-note this is the opposite for apoptosis
What are the cellular mechanisms of necrosis
-loss of ATP
-loss of mitochondrial and cell membrane integrity
-flooding with intracellular calcium
-oxygen free radicals
Is necrosis tissue death
-yes
Compare thrombus to embolus
-thrombus is a blood clot that has formed in a vessel
-an embolus is something in a vessel that has travelled somewhere else
->embolus is not always a blood clot
Give examples of embolus other than a blood clot
-atherosclerotic plaque
-bone marrow
-amniotic fluid
-air
What is venous infarct
-blood compressed in vein and cant leave
What is anoxia, hypoxia and ischemia
Anoxia
->no oxygen
Hypoxia
->less oxygen
Ischemia
->reduced or no blood flow
->usually arterial occlusion
What is ischemia reperfusion injury
-more injury can occur in ischemic tissues that are successfully re-perfused
->arterial blockage is cleared and blood flow is returned to the tissue
Why?
->more oxygen means more reactive oxygen species
->more calcium and activation of damaging enzymes
->inflammation
Is ischemia more injurious than hypoxia or anoxia with maintained blood flow
-yes
