Qbank notes Flashcards
MOA of aflatoxin and hepatocellular carcinoma
induces p53 mutation of G:C -> T:A transversion
Ochronosis
a black pigments evident in the skin due to alkaptonuria (seen in ears, nose, cheecks, etc)
MOA of Neisseria virulence factor
IgA protease- finds to Fc portion preventing
What is the molecular change seen in HbS?
a charged glutamic acid residue is replaced by a nonpolar hydrophobic valine residue at the 6thAA position in the beta subunit -> hydrophobic part of the beta chain
- causes aggregation of the hemoglobin molecule under anoxic conditions
- this is bc a hydrophobic part of the beta chin fits in a complemetary site on the alpha chain of another Hb molecule
How do you calculate the total filtration rate of a substance A?
Inulin clearance X plasma concentration of substance A
How do you calculate the Net Excretion rate of Substance A?
= CL inulin X Plasma conc of ubstance A - tubular reabsorption of substance A
What are the lipoxins and what do hey do?
Lipoxin A4 and B4:
- vasodilation
- inhibition of neutrophil chemotaxis
- stimulation of monocyte adhesion
What are the more common NNRTIs?
Nevirapine
Efavirenz
Delavirdine
What metabolic processes take place solely in the mitochondria?
- Fatty acid oxidation
- Acetyl-CoA production
- TCA
- Oxidative phosphorylation
What metabolic processes take place in the cytpolasm ONLY?
- Glycolysis
- FA synthesis
- HMP Shunt
- Protein synthesis: RER
- Steroid syndthesis (SER)
- Cholesterol synthesis
Which metabolic rxns take place in both cytosol and mitochondria?
Heme synthesis
Urea Cycle
Gluconeogenesis
What are the sites of the HMP shunt?
- Lactating mammary glands
- Liver
- Adrenal cortez
- RBCs
Benzoate
binds amino acid and leads to excretion, use in hyperammonemia
Phenylbutyrate
binds amino acid and leads to excretion- use in hyperammonemia
How is retinoic acid a teratogen?
- it alters Hox gene expression which is responisble for skeletal morphology
- limbs are thus in the wrong place or get synpolydactyly (fusion of digits)
What does the surface ectoderm become? (8)
- Lens
- Lining of oral cavity
- Rathke’s pouch -> anterior pituitary
- Sensory organs of ear
- Olfactory epithelium
- Epidermis
- Anal canal below the pectinate line
- Sweat, parotid and mammary glands
What does the neuroectoderm become?
- Brain- neurohypophysis, CNS neurons, oligodendrocytes, astrocytes, ependymal cells, pineal gland
- Retina and optic nerve
- Spinal cord
What do the neural crest cells become?
- PNS: DRG, cranial nerves, celiac ganglion, schwann cells, ANS
- Melanocytes
- Chromaffin cells of adrenal medulla
- Parafollicular C cells of thyroid
- Pia and arrachnoid
- Bones of the skull
- Odontoblasts
- Aorticopulmonary septum
What does the mesoderm give rise to?
- Muscle and bone, connective tissue
- Serous linings of body cavities
- Spleen (from foregut mesentary)
- CV
- Lymphatics
- Blood
- Wall of gut tube
- wall of bladder
- Urethra, kidney, vagina, adrenal cortex, dermis testes
What are mesodermal defects?
VACTERL Vertebral defects Anal atresia Cardiac defects Tracheo-esophageal fistulas Renal defects Limb defects (bone and mm)
What are endoderm derivatives?
- Gut tube epithelium (anal canal above the pectinate line) and luminal derivatives:
- lungs
- liver
- gallbladder
- pancreas
- eustachian tube
- thymus
- parathyroid
- thyroid folicular cells
Umbilical arteries and veins are derived from what?
Allantois
Cleft lip mechanism
failure of fusion of the maxillary and medial nasal processes
Cleft palate mechanism
failure of fusion of the lateral palatine processes, the nasal septum and/or the median palatine process
what is associated with epispadias?
exstrophy of the bladder
Dip or haploid: primary spermatocyte
Dipolid: 2N
DHT: early and late
early: causes differentiation of penis, scrotum and prostate
Late: prostate growth, balding, sebaceous gland activity
What layers of the endometrium are shed during menstration?
Stratum spongiosum and stratum compactum
Mechanism behind eclampsia
placental ischemia due to impaired vasodilation of spiral arteries
what is the cause of mortality in HELLP syndrome?
cerebral hemorrhage or ARDS
Tx of endometritis?
gentamycin and clindamycin w/wout ampicillin
how does diabetes lead to PCOS?
insulin stimulates androgen synthesis in theca cells and also inhibits SHBG
What happens when microglia are infected ith HIV?
they fuse to form multinucleated giant cells
What is found in the nodes of ranvier?
high concentrations of Na channels
what areas are not protected by the BBB?
Area postrema (responds to emetics) and OVLT (senses change in osmolarity) - in Hypothalamus
Which nucleus of the hypothalamus makes ADH?
supraoptic
which are of the hypothalamus nucleus makes oxytocin?
Paraventricular nucleus
Mnemonic for huntingtons dx
CAG expansion: caudate loses Ach and GABA
a lesion in the amygdala is associated with what?
HSV-1
What nerves are affected in Vernet syndrome
aka Jugular foramen syndrome
- CN IX, X, and XI
What is the cause of death in Freidreich’s ataxia?
hypertrophic cardiomyopathy
what risk does a subarachnoid hemorrhage carry w it and how do you treat it?
- vasospasm due to blood breakdown, 2-3 days afterwards
- tx w Nimodipine
how does friedreichs ataxia present in childhood?
kyphoscoliosis
where is t10 and why is it important?
T10 = umbilicus, important for early appendicitis pain referral
Fxn of superior colliculi?
conjugate vertical gaze
Parinaud syndrome
paralysis of conjugate vertical gaze due to lesion in superior colliculi (pinealoma)
retina whitening with cherry red spot
central retinal artery occlusion
What are the diagnostic findings seen in MS?
- increased IgG in CSF
- oligoclonal bands
how does metachromatic leukodystrophy cause nerve damage?
buildup of sulfatides leads to impaired production of myelin sheath
How does Krabbes disease lead to nerve damage?
Buildup of galactocerebroside destroys myelin sheath
Symptoms of Tuberous sclerosis
HAMARTOMAS Hamartomas in CNS and skin Adenoma sebaceum Mitral regurg Ashleaf spots Cardia Rhabdomyoma Tuberous sclerosus Autosomal dOminant Mental retardation renal Angiomyolipoma Seizures
which childhood brain tumor can produce EPO?
hemangioblastoma
Fxn of superior colliculi?
conjugate vertical gaze
Parinaud syndrome
paralysis of conjugate vertical gaze due to lesion in superior colliculi (pinealoma)
Parinaud syndrome
paralysis of conjugate vertical gaze due to lesion in superior colliculi (pinealoma)
retina whitening with cherry red spot
central retinal artery occlusion
retina whitening with cherry red spot
central retinal artery occlusion
What are the diagnostic findings seen in MS?
- increased IgG in CSF
- oligoclonal bands
how does metachromatic leukodystrophy cause nerve damage?
buildup of sulfatides leads to impaired production of myelin sheath
How does Krabbes disease lead to nerve damage?
Buildup of galactocerebroside destroys myelin sheath
Symptoms of Tuberous sclerosis
HAMARTOMAS Hamartomas in CNS and skin Adenoma sebaceum Mitral regurg Ashleaf spots Cardia Rhabdomyoma Tuberous sclerosus Autosomal dOminant Mental retardation renal Angiomyolipoma Seizures
which childhood brain tumor can produce EPO?
hemangioblastoma
What is the drug of choice for paroxysmal supraventricular tachycardia?
Adenosine- acts by slowing conduction through the AV node by hyperpolarizing the nodal pacemaker and conducting cells
Side effects of adenosine?
flushing, chest burning (due to bronchospasm) and hypotension and high grade AV block
What cell type incraeses after high dose glucocorticoid administration?
Neutrophils- bc of demargination of leukocytes previously attached to the vessel wall
What are stains for neuroendocrine markers?
- Synaptophysin
- Neuron specific enolase
- Chromogranin
