DIT Questions Flashcards
Where would you find the following in a lymph node? B cells T cells Plasma Cells Macrophages
B cells are in the follicle in outer cortex
T cells are in the paracortex
Plasma cells are in the medullary cords of the lymph node
Macrophages are in the medullary sinus
Forkhead Box Protein B3
From FOXP3 gene on the X chromosome.
Serves as a transcription factor for the development and function of regulatory T cells.
What are the female homologues of the following male structures?
Corpus Spongiosum –>
Cowper’s Glands (Blulbourethral glands) –>
Prostate –>
Glans Penis –>
Ventral Penile Shaft (penile urethra)–>
Scrotum –>
Corpus Spongiosum –> Vestibular bulbs
Cowper’s Glands (Blulbourethral glands) –> Greater Vestibular glands (of Bartholin)
Prostate –> Urethral and paraurethral glands (of skene)
Glans Penis –> Glans clitoris
Ventral Penile Shaft (penile urethra)–> labia minora
Scrotum –> labia majora
Remember you need Estrogen to get the female parts and Dihydrotestosterone to get the male parts
Intrinsic Apoptosis
Increased Bax (pro-apoptotic) and decreased Bcl-2 (anti-apoptotic) leads to increased mitochondrial permeability and cytochrome C released leading to activation of intracellular caspases
Extrinsic Apoptosis
Either:
- Fas ligand binds to FasR (CD95) or
- CD8 cell releases perforin and granzyme B
leads to activation of intracellular caspases
What is the important component of surfactant?
Surfactant made of lecithins, most important is Dipalmitoylphosphatidylcholine
What ratio indicates fetal lung maturity?
A lecithin:Spingomyelin of >2:1 in amniotic fluid
What amino acids are necessary for purine synthesis?
GAG: Glycine, Aspartate, Glutamine
Drug’s Clearance equation
Cl = (Vd x 0.7) / T1/2
What bacteria are well known for being obligate intracellular and why
Rickettsia and Chlamydia.
Unable to make their own ATP so they use the hosts ATP
“Stay inside the cell because it’s Really Cold out”
What is Achalasia?
Failure of relaxation of the lower esophageal sphincter due to loss of myenteric (Auerbach’s) plexus.
What is Peripheral Vascular Disease/Peripheral Arterial Disease?
Atherosclerosis of the peripheral arteries.
- Claudication
- Decreased peripheral pulses
- Feet may become cold to the touch
- Skin can become pale/shiny and hairless
What is a deep venous thrombosis?
A blood clot forming in the peripheral veins.
- Most likely due to immobilization.
- Leg is warm (Not cool)
- Increased calf circumference
- Moses Sign - calf tenderness with compression
- Homan’s sign - calf pain with ankle dorsiflexion (not a sensitive test)
What are the equations for cardiac output?
CO = SV x HR
CO = (rate of O2 consumption) / (arterial O2 content - venous O2 content)
What’s up with Vitamin K’s use?
Catalyzes gamma carboxylation of glutamic acid residues on various proteins.
Activates Factors II, VII, IX, and X and Protein C and Protein S
What two arachidonic acid products affect platelet aggregation?
Thromboxane A2 promotes platelet aggregation.
Prostacyclin (PGI2) inhibits platelet aggregation
What are some medications that act on microtubules?
Mebendazole (anti-helminthic) Griseofulvin (anti-fungal) Vincristine/Vinblastine (anti-cancer) Paclitaxel (anti-breast cancer) Colchicine (anti-gout)
What syndrome demonstrates a defect in microtubule polymerization?
Chediak-Higashi Syndrome.
AR, defect in lysosomal trafficking regulator gene (LYST)
Microtubule dysfunction resulting in failure of phagosome-lysosome fusion
What GI ligament separates the greater and lesser sacs?
Gastrosplenic ligament and Gastrohepatic ligament
What GI ligament may be cut during surgery to access the lesser sac?
Gastrohepatic ligament
What are the 2 GI ligaments that connect the spleen to other structures?
Splenorenal ligament and Gastrosplenic ligament
What GI ligament contains the portal triad?
Hepatoduodenal ligament.
Portal triad - hepatic artery, portal vein, common bile duct
What GI ligament connects the liver to the anterior abdominal wall?
Falciform ligament.
What is Narcolepsy and what are its characteristics?
Narcolepsy is disordered regulation of sleep-wake cycles.
Characteristics: - excessive daytime sleepiness
- hallucination - Hypnagogic (before sleep) and Hypnopompic (before awakening)
- Nocturnal and narcoleptic sleep both start with REM sleep
- Cataplexy
What is narcolepsy treated with?
Day time stimulants like amphetamines or modafinil.
Sodium oxybate can assist with sleep and reduce cataplexy
First-line treatment for erectile dysfunction and MOA
Sildenafil, Vardenafil, Tadalafil
Inhibits phosphodiesterase 5 causing increased cGMP, smooth muscle relaxation in the corpus cavernosum leading to increased blood flow and penile erection
What drugs are used to treat Crohn’s that target TNF-alpha?
Infliximab, Adalimumab and Certolizumab
What is a cholesteatoma?
Overgrowth of desquamated keratin debris located in the middle ear space against the inside of the tympanic membrane.
Can eventually erode the ossicles and external auditory canal leading to hearing loss.
Patient may present with chronic middle ear infections, grayish-white pearly lesion behind the tympanic membrane, conductive hearing loss, or vertigo
What are the adverse effects of exogenous testosterone in males?
In children: - premature puberty - premature closure of epiphyseal plates (growth restriction) In adults: - Erythrocytosis - Worsening of sleep apnea - Suppression of spermatogenesis - Increased LDL and decreased HDL
What is the initial treatment for torsades de pointes?
IV magnesium sulfate
What 3 structures give rise to the Blood brain barrier?
- Tight junctions between non-fenestrated capillary endothelial cells
- Basement membrane
- Astrocyte foot processes
what diuretics are used in hyperaldosteronism?
Spironolactone and Eplerenone: Competitive aldosterone antagonists in cortical collecting duct
Triamterene and Amiloride: Block sodium transport channels in the cortical collecting duct resulting in a decreased in the Na+/K+ exchanger
What are the different causes of homocystinuria? And how do you treat them?
- Cystationine synthase deficiency; TX with decreased methionine, increased cysteine, increased B12 and folate in diet
- Decreased affinity of cystathionine synthase for pyridoxal phosphate (B6); TX with increased vitamin B6
- Homocysteine Methyltransferase deficiency; TX with Vitamin B12
What is the pathway that the cochlea communicates a signal to the primary auditory canal?
Signal goes from cell bodies of the spiral ganglion (in cochlea) to the cochlear nuclei
then to the CL superior olivary nucleus
then to the lateral lemniscus to the inferior colliculus then the medial geniculate body
Lastly tot he primary auditory cortex
What is the structure of HbH?
This is an alpha thalassemia
Made of beta tetramers
What is the structure for Hb Barts?
This is an alpha thalassemia made of gamma tetramers.
Seen in infants and results in hydrops fetalis
What cholinergic agonist can be used to treat post-op ileus and urinary retention?
Bethanechol (direct cholinergic agonist)
What conditions can be made worse by using cholinomimetic agents?
Can exacerbate asthma, COPD, and peptic ulcers
What conditions can be helped with hyperbaric oxygen therapy?
Severe carbon monoxide poisoning
Decompression sicknes
Arterial gas emboli
Gas gangrene (Clostridium perfringens)
After a splenectomy, what would you expect to see on a peripheral blood smear?
Would expect to see Howell-Jolly Bodies
What organisms are asplenic patients susceptible to? And what vaccines should they get?
Encapsulated organisms --> SHiNE SKiS Streptococcus penumoniae Haemophilus Influenzae Neisseria meningitides E.coli Salmonella Klebsiella pneumoniae Group B Strep
What vaccines? S. pneumo, H flu type B and Neisseria meningitidis
What can increase contractility of the heart?
- Catecholamines
- Sympathetic stimulation
- Increased intracellular calcium
- Decreased extracellular sodium
- Digoxin
What can decreased contractility of the heart?
- Beta 1 blockade
- Heart failure
- Acidosis
- Hypoxia
- Calcium channel blockers like verapamil or diltiazem
- Decreased intracellular calcium
- Increased extracellular sodium
What is the pressure in the potential spaces of the body including pleural cavity, joint spaces, and pericardial cavity?
The hydrostatic pressure in these spaces is negative to help facilitate the diffusion of fluid into the spaces
- Pleural cavity: - 7 to -8 cm H2O
- Joint spaces: -3 to -5 cm H2O
- Pericardial cavity: -5 to -6 mm Hg
What is Standard deviation?
SD is a measure of how much variation there is between data in a sample
1 SD = 68%; 2 SD = 95%, 3 SD = 99.7%
What is standard error of the mean?
SEM is how well the mean of a particular sample can predict the mean of a population.
The larger the sample size, the close you get to the mean of the whole population.
SEM = SD/Sq. Rt (n)
The larger the sample size, the closer you get to the mean of the whole population
How do you calculate confidence intervals?
CI = range from [mean - Z (SEM)] to [mean + Z (SEM)]
95% CI, Z = 1.96
99% CI, Z = 2.58
The more confident you want to be, the wider your range
What are some lung cancers in NON smokers?
Most common - bronchial Adenocarcinoma
Bronchioloalveolar adenocarcinoma
malignant mesothelioma (technically a pleural cancer)
What are lung cancers that are associated with smoking?
Small cell carcinoma and Squamous cell carcinoma
Fibrous band that attaches the testis to the scrotum and aids in normal testicular descent
Gubernaculum.
Female equivalent is the Ovarian ligament and Round ligament of the uterus
Hereditary hemorrhagic telangiectasia
Osler-Weber- Rendu syndrome (AD) Findings: Telangiectasia (skin, mucous membranes, organs - liver, lung brain) Recurrent epistaxis Skin discolorations AVMs
can result in high-output heart failure
What is a case control study?
Observational and retrospective; compares a group of people with a disease to a group without a disease
Looking for a prior exposure or risk factor
Uses Odds ratio
What is a cohort study?
Observational and prospective or retrospective; compares a group with a given exposure or risk factor to a group without such exposure
Looks to see if a exposure increases the risk of a disease
Uses Relative Risk
What is a clinical trial?
Prospective, experiment
Should be controlled, randomized and double blinded
Compares outcomes from 2 different treatments
What are the actions of Prostaglandins E2?
Increases uterine tone
Causes vasodilation
Causes bronchodilation
NSAIDs inhibit PGE2!
What are the affects of Angiotensin II and Prostaglandins at the Renal arterioles?
Angiotensin II causes vasoconstriction of the efferent arterioles leading to increased GFR and filtration fraction
Prostaglandins cause vasodilation of the afferent arterioles leading to increased GFR
What’s the most common form of congenital adrenal hyperplasia?
21 hydroxylase deficiency
Decreased aldosterone and cortisol and increased androgens
Patients present with hypotension, hyperkalemia, volume depletion, masculination
What do Th1 and Th2 cells secrete?
Th1: IFN G and IL2
Th2: IL4, IL5, IL10, IL13
What inguinal hernia traverses through Hasselbach’s triangle?
Direct inguinal hernia. Begins protrusion medial to inferior epigastric vessels
What inguinal hernia traverses lateral to the inferior epigastric vessels?
Indirect inguinal hernia
What forms Hesselbach’s triangle?
Inguinal ligament, inferior epigastric vessels, and lateral wall of rectus abdominus
What are the 3 endogenous androgens in order from most potent to least?
- DHT
- Testosterone
- Androstenedione
Nonhemolytic, normocytic anemia caused by failure of destruction of myeloid stem cells
Aplastic anemia
What drugs can cause aplastic anemia?
Benzene, chloramphenicol, alkylating agents, antimetabolites, NSAIDs, propylthiouracil, methemazole