2015.04.13 Flashcards
Caudal Regression Syndrome
Patients are born with agenesis of the sacrum and occasionally lumbar spine and experiene flaccid paralysis of the legs, dorsiflexed contractures of the feet, and urinary incontinence.
Ranges in severeity from isolated anal atresia to sirenomelia.
Frequently related to poorly controlled maternal diabetes.
Vitamin A Overdose during pregnancy
Causes craniofacial abnormalities, posterior fossa CNS defects, auditory defects, and abnormalities of the great vessels (effects similar to those in DiGeorge syndrome)
Rate limiting enzyme in the urea cycle
Carbamoyl phosphate synthetase I (CPS I) - activated by N-acetylglutamate.
Nitrogen atoms in urea cycle are derived from NH3 and aspartate in the urea cycle.
Pathological vertebral fractures
fracture due from less significant force than a fracture of normal bone.
Osteoporosis due to chronic use of corticosteroids promotes osteoporosis by decreasing synthesis of bone matrix, inhibition of intestinal action of vitamin D in promoting calcium absortpion, and increased parathyroid hormone levels.
Langerhans cells
Form of dendritic cell (antigen presenting cells which present MHC Class II and B7) most commonly found in the skin and mucous membranes.
Are from myeloid stem cells.
Characteristic “racquet-shaped” intracytoplasmic granule = Birbeck granule.
Common peroneal nerve
Vulnerable to injury where it courses over the neck of the fibula.
Lesions can cause weakness of dorsiflexion (deep peroneal nerve) and eversion (superficial peroneal nerve) of the foot as well as loss of sensation over the dorsum of foot.
Inversion and plantarflexion remains intact due to action of the tibial nerve.
Low vs. High freq. detection in the ear
Low freq. best detected at apex of cochlea (near the helicotroema) since it has large and flexible basilar membrane.
High freq. best detected at base of cochlea (near the round and oval windows) since the basilar membrane there is thin and rigid.
Scala vestibuli, media, and tympani
Scala vestibuli and tympani contain perilymph
Scala media contains endolymph. Is separated from tympani by the basilar membrane. Houses the tectorial membrane and the organ of Corti (where sound is transduced into the nervous system)
Aspirin
Irreversible cyclooxygenase inhibitor that helps to prevent platelet thrombus formation by inhibiting thromboxane A2 synthesis and platelet aggregation.
Can cause bronchoconstrition and SOB/wheezing in patients with allergy.
CLopidogrel is best antiplatelet alternative.
Allopurinol
Xanthine oxidase inhibitor used in the treatment of tumor lysis syndrome and gout.
Tumor lysis syndrome - high cell turnover rate, characterized by electrolyte disturbances and acute renal failure
Paclitaxel
cytotoxic chemotherapeutic agent that binds B-tubulin and enhances microtubule polymeriazation, producing a disorganized array of microtubules within the cell during metaphase and ultimately cell death.
Sudden onset dyspnea in the setting of recent calf swelling
Strongly suggestive of pulmonary embolism
Pulmonary Embolism
Hypoperfusion of affected pulmonary parenchyma develops and leads to a redistribution of pulmonary blood flow and development of a ventilation/perfusion (V/Q) mismatch.
Hypoxemia stimulates respiratory drive, causing hyperventilation and respiratory alkalosis
Chronic sinopulmonary infections, bronchiectasis, pancreatic insufficiency, infertility due to absent vas deferens bilaterally (azoospermia)
Cystic Fibrosis
Mutation in CFTR gene which impairs ion transport.
Diagnosis: elevated sweat chloride levels, abnormal nasal transepithelial potential difference, genetic testing
Pirmary ciliary dyskinesia (Kartagener syndrome)
Dynein arm defect leads to abnormal ciliary motion & impaired mucociliary clearance
chronic sinopulmonary infections, bronchiectasis, situs inversus and infertility due to immotile spermatozoa
Diagnosis: Low nasal NO levels, bronchoscopy & EM visualization of ciliary abnormalities, genetic testing
Hypogonadotropic hypogonadism (Kallmann Syndrome)
Low testosterone in the setting of decreased FSH and LH
Pulsus Paradoxus
Decrease in systolic blood pressure of greater than 10mmHg with inspiration and occurs with conditions that impair expansion into pericardial space (increased right ventricular volume occurring during inspiration pushes the interventricular spetum toward the left, causing reduced left heart diastolic volume and stroke volume, resulting in decreased systemic blood pressure during inspiration)
Increases in cAMP in bronchial smooth muscle caused by stimulation of beta-2-adrenergic receptor
Causes smooth muscle relaxation
Phenelzine and Tranylcypromine
Monoamine oxidase inhibitors (MAOIs) that are useful for atypical depression.
Atypical Depression
Mood reactivity
Leaden fatigue (arm’s and legs feel heavy)
Rejection sensitivity (overly sensitive to light criticism)
Revered vegetative signs of increased sleep and appetite.
Transformation
Direct uptake of naked DNA from the environment by bacteria that are naturally competent:
Streptococcus pneumoniae
Haemophilus influenza
Neisseria gonorrhoeae & meningitidis
Conjugation
One-way transfer of DNA between bacterial cells through direct physical contact
Donor cells have F factor which codes for a sex pilus & other proteins necessary for gene transfer to F- recipients
