teratology Flashcards
first three leading causes of infant mortality
birth defects, prematurity/LBW, SIDS
diethylstilbestrol
antinausea: increase in cervical cancer in daughters whose mothers took this during pregnancy
tetracyclines
tooth and bone development malformations
13-cis-retinoic acid (Accutane)
analogs of retinoic acid: treatment of cystic acne.
SHH, posterior, ect. position within limbs
cardiac defects
tooth development defects
lithium
bipolar, psy conditions: can make embryos all ectoderm, disturbances in cell signaling mechanisms
characteristics of fetal alcohol syndrome
MR/low IQ
thin lips
philtrum deformation
abnormal eyelid formation
mechanism of fetal alcohol syndrome
chronic consumption of alcohol compromise of brain function facial features groove is missing above lip cardiac defects poor overall growth very prevalent
thalidomide
induced phocomelia: malformed limbs
possible teratogens
smoking, valium, zinc deficiency, high vitamin A, varicella, binge drinking, organic solvents
unlikely teratogens
aspirin birth control pills ultrasound spermicides bendectin illicit drugs video display terminals aspartame anaethestics rubella vaccine metronidazone agent orange
how susceptible is fetus to teratogens during predifferentiation period?
not very
just kills cells or embryo does not survive
how susceptible during period of early differentiation?
highly susceptible to teratogenesis
organ systems forming
how susceptible during period of advanced organogenesis
increasingly resistant to teratogenesis with increasing age.
effects of teratogens depend on four things
period of exposure
dosage
fetal genotype
maternal genotype
concept of time specificity
specific abnormality dependent on exposure at specific time during gestation
