Cell injury/ Genetics intro Flashcards
Cell injury - Deficiency
Any lack resulting in cell injury (metabolites, chemicals, signals,
energy, etc.)
Cell injury - Intoxication
Poisoning by substances that interfere with normal cellular
function
Cell Injury - Trauma
Any physical injury
* Hypothermia
* Hyperthermia
* Free radicals
* Pressure
* Foreign microorganisms
* Immune action
reversible cell response
Structural vs. Functional changes
irreversible cell response
Apoptosis – programmed cell death
Extreme structural changes resulting in
organelle breakdown and loss of cell
integrity
irreversible response in nucleus-
Karyolysis
fragment and “melt away” (degrade)
irreversible response in nucleus-Pyknosis
shrink and condense
irreversible response in nucleus- Karyorrhexis
fragment and condense
hypertrophy
increase in cell size
hyperplasia
increase in cell number
reversible functional response
alternate metabolism: oxidative phosphorylation/ glycolysis
alter size: hypertrophy/hyperplasia
cell stress proteins: heat shock proteins
organelle changes
reversible structural changes
plasma membrane blebbling
membrane-bound organelle changes
Cell intoxication example: alcohol
- ethanol–> acetaldehyde by alcohol dehydrogenase (ADH) after ethanol in crosses membrane to cytoplasm
- acetaldehyde thru both mitochondria membranes and converted to Acetic acid by aldehyde dehydrogenase (ALDH)
- Buildup of acetic acid
Exogenous origin- biological ex
outside cell
mold, venom, toxins from bacteria
Exogenous origin- nonbiological ex
radon, heavy metals, pesticides, smoke inhalation
Endogenous orgin
cell waste not regularly removed
genetic defect
alcohol (zero order- flat line)
primary nutrient deficiency
not enough nutrient- direct
secondary nutrient deficiency
around, but can’t utilize nutrient
(genetic defect—> can’t use metabolic pathway)
BRCA 1 mutation
encodes for proteins that help w/ DNA repair
increase risk of breast cancer 13% to about 60% (estrogen influenced cancer)
Chris hemsworth. has two copies of
APOE e4
Apolipoprotein E
INCREASES alzheimer’s risk by 8-12x (earlier onset, more severe)
Non-invasive prenatal testing
prenatal genetic testing
now recommended for all pregnancies
Karyotype
used to
visualize an individuals genotype
phenotype
outward
manifestation of genotype, a
characteristic that can be
measured
Variable expressivity
Degree to which a genotype exhibits its phenotypic expression
Persons with the same disease causing mutation may show striking
differences in clinical manifestation
VE
penetrance
A disease either shows reduced penetrance or it does not
– Reduced or incomplete penetrance means that not everyone with a
mutant genotype will be affected
have genetic mutation, some have disease/ some don’t
penetrance
Proband
the affected individual
who brings the family to medical
attention, typically the first known
affected family member (arrow)
Making a Pedigree
Horizontal row is a generation
– Roman Numerals for generation, Arabic numerals for
individual
– Siblings - oldest to left
– Deceased individuals have strikethrough
– Proband has arrow
Phenylketonuria (PKU)
Genetic defect
rendering phenylalanine
hydroxylase inactive
Symptoms are caused by a substrate accumulation and an end-product deficiency
Hyperphenylalaninemia
causes most of the clinical
manifestations of PKU
enzyme from phenylalanine–> Tyrosine
Phenylalanine hydroxylase (PAH)
PKU tyrosine leads to….
melanin catecholamines , protein synthesis, ketone bodies + gluconeogenesis
PKU and gene therapy
restricted diet
