Foundations Flashcards
What structures come from neural crest?
Melanocytes, aorticopulmonary septum, ganglia (autonomic, dorsal root, enteric), iris stroma, chromaffin cells, cranial nerves, odontoblasts/ossicles, parafollicular (C) cells, sclerae (MAGIC COPS)
What structures develop from the neural tube? (from neuroectoderm)
CNS (neurons, oligodendrocytes, astrocytes, ependymal cells), pineal gland, posterior pituitary, retina
What structures come from surface ectoderm?
lens, olfactory epithelium, inner ear, anterior pituitary, oral epithelium, parotid glands, enamel of teeth, epidermis, sweat glands, mammary glands, distal anal canal
What structures develop from mesoderm?
muscle, bone, bone marrow, blood cells, heart, blood vessels, lymphatics, upper vagina, kidneys, adrenal cortex, gonads, dermis
What structures develop from endoderm?
GI tract, submandibular glands, sublingual glands, liver, gallbladder, pancreas, lungs, thymus, thyroid follicular cells, lower vagina, bladder epithelium, urethral epithelium
What does the epiblast give rise to?
All three germ layers: ectoderm, mesoderm, endoderm
What does the hypoblast give rise to?
endoderm
What happens in weeks 3-8 of embryonic development
embryonic period -> organogenesis
most susceptible to teratogens
What happens in week 4 of embryonic development?
4 chamber heart, 4 limb buds
What happens in week 8 of embryonic development?
fetal movement (eight/gait)
What happens in week 10 of embryonic development?
sex-specific genitalia (puberty @ age 10)
What is the relationship between the notochord, the neural crest, the neural plate, and the neural tube?
The notochord is formed from mesoderm, which induces ectoderm to form the neural plate.
Edges of the neural plate fold up and form the neural tube (becomes brain and spinal cord)
Pieces bud off and surround the neural tube, called the neural crest
What are the characteristics of fetal alcohol syndrome?
facial abnormalities (narrow eye openings, wide-set eyes, smooth philtrum, thin upper lip, cleft palate)
intellectual disability
microcephaly
holoprosencephaly
2 things that allow progression from G1->S
CDK4-cyclin D
CDK2-cyclin E
2 things that allows progression from G2->M
CDK2-cyclin A
CDK1-cyclin B
What is I cell disease?
Deficiency in mannose phosphorylation
No mannose-6-phosphate to target lysosomal proteins -> secretion out of cell instead of into lysosomes
Death by age 8
Corneal clouding, coarse facies, hepatosplenomegaly, skeletal abnormalities, restricted joint movement
May have intellectual disability
What must be present on a protein in order for that protein to gain entry into the nucleus?
nuclear localization signals
PALS -> proline, arginine, lysine
What intermediate filament is part of epithelial cells?
In what cancer does it stain?
cytokeratin; carcinoma
What intermediate filament is part of muscle cells?
In what cancer does it stain?
desmin; rhabdomyosarcoma, leiomyosarcoma
What intermediate filament is part of astrocytes and Schwann cells? In what cancer does it stain?
glial fibrillary acid proteins (GFAP); glioblastoma
What intermediate filament is part of axons within neurons? In what cancer does it stain?
neurofilaments; neuroblastoma
What intermediate filament is part of the nuclear envelope and DNA within?
Nuclear lamins
What intermediate filament is part of connective tissue (fibroblasts, leukocytes, endothelium)? In what cancer does it stain?
Vimentin; sarcomas
What drugs act on microtubules?
- Vinka alkaloids -> vincristine and vinblastine (block polymerization of microtubules)
- Taxans -> Paclitaxel, Docetaxel (stabilize the microtubules)
- Colchicine
- Griseofulvin
- Benzimidazoles -> mebendazole, albendazole, thiabendazole
What are the defects seen in Kartagener Syndrome?
chronic sinusitis, broncheiectasis, situs inversus
Part of primary ciliary dyskinesia -> Immotile cilia due to dynein arm defect; also have infertility
What are the effects of thromboxane A2?
increased platelet aggregation
increased vascular tone
What are the effects of prostaglandins?
increased uterine tone (PGE2, PGF2alpha)
decreased vascular tone (PGE1)
What are the effects of PGI2?
decreased platelet aggregation
decreased vascular tone
decreased uterine tone
What are the effects of leukotrienes? What inhibits them?
neutrophil chemotaxis
increased bronchial tone (LTC4, LTD4, LTE4)
Inhibited by Zafirlukast, Montelukast
Where are collagens types I, II, III, and IV found?
type I - bones, skin, dentin, scar tissue
type II - cartilage, vitreous body, nucleus pulposus
type III - blood vessels, skin, uterus, embryonic/fetal tissue, granulation tissue, reticular fibers
type IV - basement membrane
(strong, slippery, stretchy, BM)
Osteogenesis imperfecta type 1
Most common Autosomal Dominant insufficient amounts of normal type 1 collage or slightly abnormal type 1 collagen Multiple fractures, limb deformities Blue sclerae hearing loss dental abnormalities usually due to COL1A1 and COL1A2 defects
Osteogenesis imperfecta type 2
Autosomal Dominant
death in utero or in the neonatal period
Classic Ehlers-Danlos
affects mainly type V collagen and type I collagen
defects in COL5A1 and COL5A2
hyper extensible skin and joint hypermobility
Hypermobility Ehlers-Danlos
Most common
Joint hypermobility without hyper extensible skin
Vascular Ehlers-Danlos
defect int he synthesis of Type III collagen
arterial rupture, hemorrhages, easy bruising, intracranial aneurysms (berry and aortic)
Alport Syndrome
defect of type IV collagen nephritis and kidney failure hearing loss eye problems (cataracts, lenticonus) Can't see, Can't pee, Can't hear a high C
Marfan Syndrome
defect in fibrillan (component of elastin)
hyperplastic joints, disorders of the heart valves and aorta, tall stature, long arms and legs; long fingers (arachnodactyly), precuts carinatum (anterior protrusion of sternum)
alpha 1 antitrypsin deficiency
defective alpha1-antitrypsin -> reduced inhibition of elastase -> increased degradation of elastin
destruction of elastin in alveoli -> panacinar emphysema
accumulation of alpha1-antitrypsin in hepatocytes -> hepatitis, cirrhosis, hepatocellular carcinoma
**See emphysema in a nonsmoker -> think of this (esp in young people)
Which amino acids are found in large concentrations in collagen? In elastin?
Collagen - hydroxyproline, proline, glycine
Elastin - glycin & proline
What is the role of vitamin C in collagen production?
vita helps with hydroxylation of lysin and proline
Lack = scurvy -> poor wound healing, swollen gums, bleeding gums, anemia
