Teratology

Question 1

what is teratology?

Answer 1

study of the causes, mechanisms, and manifestations of developmental deviations of either structural or functional nature

Question 2

what are the causes and their percents of malformations?

Answer 2

25% genetic or chromosomal; 10% known environmental factors; 65% unknown (mix of genetic and environmental)

Question 3

4 causes of malformations

Answer 3

genetic, toxic, nutritional, infectious

Question 4

principles of teratology

Answer 4

–toxicity depends on genotype and manner in which it interact with adverse enviro factors; –susceptibility varies with developmental stage (peaks at day 30, early differentiation–early organogenesis); teratogens have specific mechanisms to cause teratogenicity; final manifestations of abnormal development; horizontal transfer (agents through placenta to fetus); increased dose=increased manifestation;

Question 5

stages of developmental

Answer 5

predifferention; early differention; advanced organogenesis

Question 6

causes of abnormal embryogenesis

Answer 6

1. excessive cell death; 2. failure of cell interaction; 3. mechanical disruption; 4. reduced biosynthesis; 5. impaired morphogenic movement; 6. altered differentiation schedule

Question 7

what are the sites of teratogenesis?

Answer 7

fetus–direct; fetal-placental unit; mother–altered homeostasis (in early preg, altered homeo. in fetus is fatal; in late preg, not too bad); father–sperm

Question 8

factors affecting fetal dose

Answer 8

maternal dose, maternal metabolism; charge; molecular weight/size; placental transfer; protein binding; plasma half life; maternal absorption rate

Question 9

where do FASD kids see abnormalities?

Answer 9

growth, CNS, craniofacial, skeletal, heart, and other

Question 10

effects of prenatal ethanol exposure

Answer 10

perinatal mortality, pre+post natal growth retardations; congenital malformation; CNS dysfunction; also tend to see social, immune, and behavioural issues; also higher incidence of cancer

Question 11

risk factors for FASD

Answer 11

1. drinks per day; race; altered nutrition; drug use; genetic susceptibility; maternal health, parity and maternal age

Question 12

mechanisms of action of EtOH

Answer 12

direct embryonic cell damage; maternal malnutrition; fetal nutrition; depressed protein synthesis; fetal hypoxia

Question 13

pesticides discussed in class

Answer 13

OPs, carbamate; organochlorides; herbicies; fungicides

Question 14

mechanism of action of thalidomide

Answer 14

1. riboflavin deficiency; neuronal degradation; decreased protein synthesis

Question 15

DES mechanisms

Answer 15

altered cell differentiation; estrogenization; direct carcinogen; 2-hit carcinogen