Combank 4 Flashcards
Dipeptidyl peptidase-4 (DPP-4) inhibitors prevent what from being broken down?
incretins
Incretins serve what function?
They are responsible for increasing glucose dependent insulin secretion from pancreatic beta cells and decreasing gastric emptying time
Name two examples of DPP-4 inhibitors
Sitagliptin and saxagliptin; end in “GLIPTIN”
What is exenatide?
an incretin mimetic
What does acarbose do?
it inhibits intestinal brush border alpha glucosidases thereby decreasing starch and disaccharide absorption in the gut;
Acarbose and Miglitol are in what class of diabetic drugs?
alpha glucosidase inhibitors
What is the mechanism of action of sulfonylureas?
close K+ channel in beta cell membrane, so cell depolarizes –> triggering insulin release via increased Ca2+ influx
Name two first generation sulfonylureas
Tolbutamide; Chlorpropamide; end in “AMIDE”
What is pramlintide and what does it do?
amylin analogue; secreted by the pancreas along with insulin and helps regulate glucose absorption by slowing down gastric emptying; decreases glucagon secretion
What class of diabetes drugs is metformin in? what is the MOA?
biguanides; exact MOA is unknown; decreases gluconeogenesis, increase glycolysis, increase peripheral glucose uptake (insulin sensitivity)
Choroid plexus papillomas are most commonly seen in what population and what does it result in?
most common in children <2 y.o.; result in increased CSF production and obstruction of CSF outflow leading to hydrocephalus
What is the hypothalamus responsible for controlling?
hunger and thirst, anterior and posterior pituitary regulation, autonomic regulation; temperature regulation, sexual urges, mediation of osmolarity and sensation of nausea from the area postrema
Function of anterior hypothalamic nucleus?
acts as a heat-loss center (esp. the pre-optic area); controls body temperature through vasodilation and sweating; destruction of this center results in hyperthermia
Function of the posterior hypothalamus?
produces body heat and controls body temperature through vasoconstriction and shivering; does not have direct input from the central thermoreceptors but it is inhibited by the anterior hypothalamus when body temperature rises
Lesions to the posterior hypothalamus result in?
poikilothermia; inability to regulate body temperature
Function of the ventromedial nucleus of the hypothalamus?
satiety; destruction results in hyperphagia and weight gain
Function of the lateral nucleus of the hypothalamus?
hunger; destruction results in anorexia, failure to thrive (infants)
A lesion of the amygdala results in what syndrome?
Kluver-Bucy syndrome; manifests as hyperorality, hypersexuality, and disinhibited behavior
Kluver-Bucy Syndrome is associated with what type of infection?
Herpes simplex virus type I
The amygdala is primary responsible for what function?
processing memory and emotion reactions
What is the basal ganglia composed of and what is it responsible for?
caudate nucleus, putamen, globus pallidus, substantia nigra, subthalamic nucleus; responsible for voluntary movements and postural adjustments
The cerebellum located above the 4th ventricle is responsible for?
regulating balance and fine motor movements
A lesion of the cerebellum results in what type of deficits?
ipsilateral deficit b/c the cerebellar fibers decussate at two different points; falls toward side of lesion, intention tremor and limb ataxia
A lesion to the hippocampus can result in?
anterograde amnesia - the inability to make new memories
Function of the hippocampus?
plays a major role as part of the limbic system which is responsible for the 5 F’s - feeding, fleeing, fighting, feeling, sexual drive
Crohn’s disease can affect which part of the GI system?
can affect any part of the GI system from mouth to anus; usually terminal ileum and colon; skip lesions, rectal sparing
Manifestations of Crohn’s disease
mostly causes abdominal pain, diarrhea (with blood if there is marked inflammation), vomiting and weight loss; ALSO causes migratory polyarthritis, erythema nodosum, ankylosing spondylitis, uveitis and kidney stones
What life style habit can exacerbate Crohn’s disease?
smoking
Crohn’s disease patients have serum antibodies that are positive for?
Saccharomyces cerevisiae (ASCA)
Biopsy of Crohn’s disease would show?
TRANSMURAL inflammation and non-caseating granumlomas
Bloody diarrhea is most common in which inflammatory bowel disease?
Ulcerative colitis
What is a special characteristic of the inflammation seen in Crohn’s disease?
non-continuous pattern known as SKIP LESIONS
Inflammation seen in Ulcerative colitis is restricted to what areas?
inflammation is limited to the mucosa and superfiicial submucosal layer of the intestinal wall
Iron is absorbed in what part of the small intestine?
duodenum
Folate is absorbed in what part of the small intestine?
jejunum
Vitamin B12 is absorbed in what part of the small intestine?
ileum
What is ferritin and when would it be low?
Ferritin is the cellular storage protein for iron; it will be low if there is no iron to store or if iron stores have been depleted
What is transferrin and when is it increased?
Transferrin is the major transporter for iron trafficking through the plasma; hepatic synthesis of transferrin is INCREASED in an iron deficient state
What are the lab findings in iron deficiency anemia?
Elevated transferrin; elevated total iron binding capacity (TIBC) with a depressed transferrin saturation; low serum iron concentration; low ferritin
Sickle cell disease is in what category of anemias?
normocytic, normochromic hemolytic anemia
Haptoglobin is responsible for binding what in blood?
free hemoglobin
What is the laboratory presentation of sickle cell disease?
anemia, reticulocytosis, unconjugated hyperbilirubinemia, elevated serum LDH, low serum haptoglobulin
What is the laboratory presentation of anemia of chronic disease?
chronic inflammatory states causes body to store iron (macrophages trap and store iron); produces decreased serum iron, normal to increased serum ferritin; anemia
Beta thalassemia is most common in people from what descent?
Mediterranean
What category of anemia is beta thalassemia in?
microcytic, hypochromic anema
What is prevalence?
of people who have the disease at a particular point in time or time period / # of people at risk
What is incidence?
of new cases in a specified time period divided by the total number of people at risk
How does screenings affect incidence and prevalence for most diseases?
incidence and prevalence decreases
How does emphysema affect gas exchange in the lungs?
poor pulmonary gas exchange and air trapping; destruction of the alveolar-capillary interface leading to decreased diffusion of oxygen into the blood; air trapping occurs due to loss of elasticity of the lung parenchyma
Pyloric stenosis is most commonly seen in what population of patients?
it is a congenital anomaly most common in male infants at 2-3 weeks of life
How does pyloric stenosis present?
presents as persistent NON-BILIOUS projectile vomiting; physical exam reveals an olive shaped mass in the region of the distal stomach
How does persistent vomiting affect physiologic pH?
gastric juices contain large quantities of hydrogen and sulfide making it acidic; multiple episodes of vomiting gastric contents leads to an increase in physiologic pH via loss of hydrogen and chloride ions while retaining bicarb
What are normal physiologic pH values?
7.35 to 7.45
Salicylate toxicity results in what type of pH imbalance?
metabolic acidosis
What is deficient in Lesch-Nyhan syndrome?
Hypoxanthine-guanine phosphoribosyl transferase (HGPRT)
What is the most common site for bowel obstruction?
small bowel
What is the most common cause of bowel obstruction?
adhesions
What are some typical symptoms of bowel obstruction?
severe colicky abdominal pain, abdominal distension, nausea and vomiting and fever and tachycardia
How should pyelonephritis be treated in pregnancy?
it must be treated immediately and aggressively; it can lead to pre-mature labor b/c bacterial toxins can cause early contractions; patient should be hospitalized and given IV antibiotics
Preferred treatment of pyelonephritis in pregnancy studies
ceftriaxone OR cefepime OR aztreonam OR ampicillin and gentamicin
What class of antimicrobials does gentamicin belong to and what is the MOA?
Aminoglycoside; binds to bacterial 30S ribosomal subunit to inhibit formation of initiation complex for protein synthesis
Name the organism: lactose negative on MacConkey agar; produces hydrogen sulfide (a black precipitate); transmitted through contaminated food; symptoms include fever, diarrhea that can contain RBCs and abdominal cramps 7-12 hours after infection
Salmonella typhimurium
Name the organism: lactose positive on MacConkey agar; do not produce hydrogen sulfide; different strains can cause different types of diarrhea
E. coli
Lactose and hydrogen sulfide status for Proteus mirabilis
Lactose negative; produces hydrogen sulfide
Shigella is more commonly found in what populations?
children who attend daycare and patients in mental institutions
How does salmonella typhimurium cause its symptoms?
It does not have an enterotoxin; rather, it elicits an immune response that leads to increased intracellular cAMP levels – this accounts for the watery diarrhea
How does the Shiga toxin of shigella species and the Shiga-like toxin of EHEC work?
Irreversibly nicks the 60s ribosome, resulting in inhibition of protein synthesis – leads to cellular death and blood diarrhea
What is leptospira?
a gram negative question marked shaped spirochete found in animal urine
What symptoms does leptospira cause?
flu-like symptoms, HA, fever, abdominal pain; unique symptoms are jaundice and photophobia
Celiac disease is an AI disease with Abs against ?
gluten (gliadin)
What other AI disease commonly occurs with celiac disease?
Hashimoto thyroiditis
How does aspirin work?
irreversibly binding to the enzyme cyclooxygenase which prevents the production of prostaglandins and thromboxane synthesis
How does heparin and its low molecular weight derivatives (enoxaparin, dalteparin) work?
binds to the enzyme inhibitor antithrombin III causing a conformational change that results in accelerated activity; activated antithrombin III then inactivates thrombin and other proteases involved in blood clotting, especially factor Xa
What class of drug is clopidogrel in and what is the MOA?
ADP receptor inhibitors; works by specifically and irreversibly binding to ADP receptor located on platelet cell membranes; blockade of the ADP receptor inhibits platelet aggregation by inhibiting the glycoprotein IIb/IIIa pathway, which functions as a fibrinogen receptor
What class of drug is Tissue plasminogen activator in? What is the mechanism of action?
Thrombolytics; catalyze conversion of plasminogen to plasmin, which is the major enzyme responsible for clot breakdown
What is Boerhaave’s syndrome?
Presents with retching and vomiting followed by severe retrosternal chest pain and abdominal pain; involves tearing of the esophagus with stomach contents forced into the mediastinum
What is the triad of symptoms seen in patients with fat emboli syndrome?
hypoxemia, neurologic abnormalitiies, petechial rash
What is the MOA of cisplatin and what is it used for?
antineoplastic that alkylates and cross-links DNA; used in the treatment of testicular, bladder, ovary and lung carcinomas
What are the side effects of cisplatin?
nephrotoxicity, acoustic nerve damage, peripheral neuropathy that can lead to foot or wrist drops
How does Bleomycin work?
antineoplastic agent that inhibits DNA synthesis through free radical formation that induces single strand breaks in DNA; bleomycin inhibits DNA, RNA and protein synthesis in the G2 and M phases of the cell cycle
What is bleomycin used for?
Hodgkin lymphoma and testicular cancer
What are the side effects of bleomycin?
pulmonary fibrosis – can lead to restrictive lung disease
How does busulfan work?
antineoplastic that works by alkylating and cross-linking strands of DNA and is cell cycle nonspecific
What is busulfan used for?
treatment of chronic myelogenous leukemia or to ablate a patient’s bone marrow before bone marrow transplantation
What are side effects of busulfan?
pulmonary fibrosis and hyperpigmentation
How does etoposide work?
a topoisomerase II inhibitor that leads to the inhibition of DNA synthesis; primarily acts in the S and G2 phases of the cell cycle
What is etoposide used for?
small cell carcinoma and testicular carcinoma
What are the SEs of etoposide?
myelosuppression, GI irritation and alopecia
Steeple sign on x-ray (an inverted V shape in the trachea) is usually associated with?
croup
The thumbprint sign is commonly associated with?
epiglottitis
What is the most common inherited bleeding disorder?
von Willebrand’s disease (vWD)
What is von Willebrand’s disease?
AD disease; deficiency in vWF, a carrier protein for factor VIII; results in prolonged bleeding time
What type of inheritance does PKU have?
autosomal recessive
What causes PKU?
defect in the metabolism of phenylalanine, which is normally converted to tyrosine by phenylalanine hydroxylase
Common conditions that cause transudative effusions are?
CHF, cirrhosis, nephrotic syndrome
Common conditions that cause exudative effusions
lung infections, malignancy, pulmonary embolism, collagen vascular disease
Personality changes, lack of social judgment and difficulty concentrating may indicate a lesion to what part of the brain?
Frontal lobe; this lobe is responsible for planning, concentration, orientation, language, motor regulation, abstraction and judgment
Mammilary bodies, a part of the limbic system are responsible for? damage to this area can lead to what?
processing memoring; damage can result in Wernicke-Korsakoff syndrome – confusion, ataxia, ophthalmoplegia, memory loss, personality changes
What type of inheritance does Huntington’s disease have?
autosomal dominant
On what chromosome is the mutation for Huntington Disease?
Chromosome 4 – CAG repeats
What physiologic parameters are expected in cardiogenic shock?
high preload, low CO, adequate intravascular volume
What physiologic parameters are expected in hypovolemic shock?
low preload, low CO, decreased intravascular volume
What physiologic parameters are expected in distributive shock?
normal/low preload, high CO, decreased vascular resistance
What physiologic parameters are expected in obstructive shock?
Low preload, low CO, increased vascular resistance
In a normal distribution ____% of all observations lie within one SD
68
In a normal distribution ____% of all observations lie within two SD
95
In a normal distribution ____% of all observations lie within three SD
99.7
What nerve passes posterior to the medial epicondyle?
ulnar nerve
What nerve supplies cutaneous innervations to the 5th digit and half of the 4th digit
ulnar nerve
What nerve travels beneath the biceps tendon on the forearm?
median nerve
Which nerve supplies cutaneous innervations to the first three and a half digits?
median nerve
What Ab is specific for systemic sclerosis (scleroderma)?
Anti-Scl-70 antibody
CREST syndrome is a type of?
scleroderma
