Uworld Flashcards
List 8 locations where you find type I collagen?
- Dermis
- Bone
- Tendons
- Ligaments
- Dentin
- Cornea
- Blood vessels
- Scar tissue
What type of collagen is affected in osteogenesis imperfecta?
Type I collagen
List 3 locations where you find type II collagen
- Cartilage
- Vitreous humor
- Nucleus pulposus
List 7 locations where you find type III collagen?
- Skin
- Lungs
- Intestines
- Blood vessels
- Bone marrow
- Lymphatics
- Granulation tissue
Type IV collagen is found where?
Basement membranes
Due to the overlap of normal behavior in preschoolers and sx’s of ADHD, the diagnosis is not given before what ages?
4-5 y/o
What is the embryological defect comprising Pierre-Robin sequence and what is seen in these children?
- Severe micrognathia results in posterior displacement of the tongue (glossoptosis)
- Prevents further fusion of the secondary palate (cleft palate)
Which blot procedure is used for DNA, mRNA, and protein?
- DNA = Southern blot
- mRNA = Northern blot
- Protein = Western blot
The best method for determining whether a gene is being expressed is by using what type of blot?
Northern blot for mRNA; will show if gene of interest is being transcribed
Which interleukin is produced by macrophages infected by mycobacteria, which in turn stimulates T cells and NK cells to produce IFN-gamma?
IL-12
Autosomal recesssive deficiencies of what receptor result in disseminated mycobacterial disease in infancy or early childhood?
IFN-gamma receptor
Leukocyte adhesion deficiency is a rare immunodeficiency resulting from a defect in what?
- CD18
- Present w/ delayed separation of umbilical cord, recurrent cutaneous infections w/o pus formation, and poor wound healing
Injury to a branch of which nerve during appendectomy causes decreased sensation at the suprapubic region?
Anterior branch of Iliohypogastric n.
Which nerve arises from L2-L4 roots and innervates the skin of the medial thigh + provides motor function to the adductor ms. of the LE?
Obturator n.
Which nerve arising from L1 accompanies the spermatic cord through the superficial inguinal ring providing sensation to the upper and medial thigh and parts of the external genitalia?
Ilioinguinal n.
Left ventricular gallops (S3 and/or S4) are best heard how?
Using bell over the cardiac apex while pt is left lateral decubitus and listening at end of exhalation
Sudden upward jerking of the arm at the shoulder can cause injury to which nerves?
Lower trunk of brachial plexus (C8-T1) contributing to median and ulnar n.
Which fetal anomalies associated with decreased fetal swallowing can lead to polyhydramnios?
- GI obstruction: esophageal, duodenal, or intestinal atresia
- Anencephaly
Brown Sequard syndrome results from hemisection of the spinal cord and is characterized by what 3 findings?
- Ipsilateral spastic paralysis (due to corticospinal tract injury)
- Ipsilateral loss of tactile/vibratory/position sensation (dorsal columns)
- Contralateral loss of pain and temp (spinothalamic tract) 1-2 levels below the lesion
In patients with PKU what AA becomes essential and why?
Tyrosine as it cannot be synthesized from phenylalanine in these pt’s
Which immune cells play a prominent role in defense against parasitic infection; predominantly via what substance?
- Eosinophils
- Release major basic protein from their granules, which acts as a potent toxin
Which fungi is associated with branching hyphae (25°C) and on biopsy is large, round yeasts w/ doubly refractile wall and single broad-based bud?
Blastomyces dermatidis
Which fungi is associated with oval yeast cells found within macrophages?
Histoplasma capsulatum
Biopsy of which fungal infection will show cells covered in budding blastoconidia?
Paracoccidioides brasiliensis
Respiratory bronchioles lack which 2 features found in the bronchi?
Cartilage and glands
Acute intermittent porphyria (AIP) may result from an autosomal dominant defect in which enzyme?
Porphobilinogen deaminase (PBGD)
What is the 5 P’s mnemonic for the clinical manifestations of Acute Intermittent Porphyria?
- Painful abdomen
- Port wine - colored urine
- Polyneuropathy
- Psychological disturbance
- Precipitated by drugs (and alcohol and starvation)
A patients urine turning black when exposed to air is a characteristic finding of what disease?
Alkaptonuria (autosomal recessive); deficiency of homogentisic acid dioxygenase
What is the function of T-tubules found in striated muscle?
- During contraction, allow depolarization impulse to rapidly propogate thru interior of muscle fiber
- Ensures Ca2+ release occur uniformly throughout the fiber, allowing for synchronized contraction of myofibrils in each cells
Describe the route of an embolus leading to retinal artery occlusion.
Internal carotid –> Ophthalmic a. –> Retinal a.
Intellectual disability, gait or posture abnormality, eczma, and a musty body odor are signs of what disease; inherited how?
PKU; autosomal recessive
Which cell structure can be identified on electron microscopy by their characteristic double membrane and wavy cristae?
Mitochondria
What is the most common non-nuclear DNA found in eukaryotic cells, which resembles prokaryotic DNA (small circular chromosome)?
Mitochondrial DNA (mtDNA)
What is the karyotype of a complete vs. partial hydatidiform mole?
- Complete: 46,XX
- Partial: 69,XXY or 69,XXX
What is the embryological defect leading to Tetralogy of Fallot?
Abnormal neural crest cell migration –> anterior and cephalad deviation of infundibular septum
What is the most common trigger for atrial fibrillation?
Aberrant electrical foci in the pulmonary veins near their ostia into the left atrium
An irregularly irregular rhythm with variable R-R intervals and absence of P wavs on ECG is consistent with what?
Atrial Fibrillation
What is Hartnup disease; inheritance pattern; major clinical manifestations?
- Autosomal recessive disorder due to inactivating mutations affecting neutral AA transporter; particularly affecting tryptophan
- Clinical manifestations due to niacin deficiency: pellagra-like skin eruptions + cerebellar ataxia
- Excessive amounts of neutral AA’s in the urine
What is unique about DNA polymerase I?
- Only prokaryotic polymerase that has 5’ to 3’ exonuclease activity; in addition to 3’ to 5’ polymerase/exonuclease activities
- Functions to remove RNA primer and repair damaged DNA sequences
Describe the murmur and location heard with patent ductus arteriosus (PDA)?
Continous murmur heard best in the left infraclavicular region with maximal intensity at S2
Optic tract lesions result in what type of visual field defect?
Contralateral homonymous hemianopia and relative afferent pupillary defect (Marcus Gunn pupil)
Budding yeasts with thick capsules are characteristic of which organism?
Cryptococcus neoformans
Where is the majority of the water filtered by the glomeruli reabsorbed, regardless of hydration status?
Proximal tubules
How do you calculate attack rate of a study?
of people affected / total # of people at risk
Primary oocytes arrest in which phase of cell cycle until ovulation and then secondary oocytes arrest in which phase until fertilization?
- Primary oocytes in prophase of meiosis I until ovulation
- Secondary oocytes in metaphase of meiosis II until fertilization
Which enzyme released by injured hepatocytes and bacteria hydrolyzes bilirubin glucuronides to unconjugated bilirubin leading to pigmented stones?
Beta-glucuronidase
Why must patients receive Mefloquine chemoprophylaxis for 4 weeks upon return from trip to areas where P. falciparum is endemic?
- To ensure that parasistes released from liver are destroyed when they infect RBC’s (liver schizonts rupture over 8-30 days)
- Mefloquine actively destroyes replicating parasites within RBC’s, however, is inactivated in liver and has no efficacy against hepatic schizonts
Gallstone ileus results from passage of a large gallstone through a cholecystenteric fistula into the small bowel where it ultimately causes obstruction where?
Ileum
Primary biliary cholangitis presnts with similar histopathological findings in the liver as what other condition?
GVHD
Isolated systolic HTN is due to what?
Age-related stiffness and decreased compliance of the aorta and major peripheral arteries
What is the effect of an increase in estrogen activity as seen in pregnancy or post-menopausal estrogen replacement therapy?
↑ the level of TBG –> ↑ in total T4 levels as well as total T3
What is the gold standard test for detecting a chromosomal microdeletion?
FISH
Vascular beds in which organ are unique in that as tissue O2 content decreases the arterial/arteriolar resistance increases?
Lungs –> diverts blood away from underventilated lung regions toward well-ventilated lung areas to minimize V/Q mismatch = efficent gas exchange
Serum levels of what are the most sensitive test for hypothyroidism?
TSH
A 2-year old girl with ambiguous genitalia, HTN, and hypokalemia is most likely to have a deficiency in what?
11ß-hydroxylase = Congenital adrenal hyperplasia
What is the most common GI abnormality associated with Down Syndrome?
Duodenal Atresia: first few days of life, bilious emesis; “double-bubble” sign
What is the hallmark of peroxisomal disorders (i.e., Zellweger syndrome, Adrenoleukodystrophy)?
Buildup of VLCFA’s and branched-chain (i.e., phytanic) FA’s due to impaired oxidation
What is the most common cause of alarming bloody or serosanguineous (i.e., blood tinged) nipple discharge; what is seen histologically?
- Intraductal papilloma
- Proliferation of papillary cells in a duct or cyst wall with fibrovascular core
