test #8 3.21 Flashcards
1
Q
kinesin
A
MT-associated motor protein involved w/ anterograde transport of intracellular vessicles / organelles towards + end (DISTANT from nucleus)
2
Q
microvilli contains..
A
actin thin filaments (NOT microtubules)
3
Q
isotype class switching occurs via..
A
modification of immunoglobulin GENOME (DNA recombinase & enzymes that excise loops of DNA not being used)
4
Q
hyper IgM syndrome
A
mutation in enzymes responsible for isotype switching in B cell, or CD40L in T cells. rx: IVIG
5
Q
what is present in colostrum
A
initial maternal milk, contains IgA dimers, joined at Fc region w/ J chain
6
Q
most common B-cell related deficiency?
A
selective IgA deficiency
7
Q
clinical presentation of hyperIgM syndrome (2)
A
(1) lymphoid hyperplasia and (2) recurrent sinopulmonary infections
8
Q
amino acid attachment site on tRNA
A
3’
9
Q
what is contained in the t(psi)C arm (near 3’ end) of tRNA and D loop (near 5’ end)?
A
t(psi)c arm has 3 nucleotide sequence present in all tRNA molecules (ribothymidine, pseudouridine, and cytosine). D loop has unpaired bases
10
Q
5’ end of tRNA serves to..
A
composed of terminal guanosine. does not participate in amino acid or mRNA binding.
11
Q
what is the smallest subtype of cellular RNA?
A
tRNA
12
Q
sensitivity
A
of the people who have disease, how many will test positive (a/a+c)
13
Q
specificity
A
of the people without disease, how many will test negative (d/b+d)
14
Q
false positive
A
(1-specificity) x no. people w/o disease
15
Q
false negative
A
(1-sensitivity) x no. people w/ disease
16
Q
alkaptonuria
A
benign disorder of tyrosine metabolism. autosomal recessive deficiency of homogentisate oxidase (blocked metabolism of phenylalanine and tyrosine at level of homogentisate), preventing conversion of tyrosine to fumarate. homogentisic acid accummulates and excreted in urine. turns black if allowed to stand & oxidize. homogentisic acid deposition in collagen of CT, tendon, and cartilage –> ochronosis –> blue-black pigmentation most evident on ears, nose, and cheeks
17
Q
black urine on standing
A
alkaptonuria and acute intermittent porphyria (?)
18
Q
alkaptonuria clinical presentation
A
urine turns black when standing. blue-black pigmentation most evident on ears, nose, and cheeks (homogentisic acid deposition in collagen of CT, tendon, and cartilate, causing “ochronosis”
19
Q
phenylketonuria (PKU)
A
defect in phenylalanine hydroxylase (smaller %age have defect in dihydrobiopterin reductase deficiency). impaired conversion of phenylalanine to tyrosine.
20
Q
cysteine synthesis
A
sulfur-containing amino acid synthesized from amino acid serine and homocysteine (which is derived from methionine)
21
Q
histidine degradation
A
histidine –> FIGLU (formiminoglutamate) —subsequent rxn–> transfer one carbon from FIGLU to THF, then release NH4+ and glutamate in the process. glutamate subsequently deaminated to form an alpha-ketoglutarate that enters TCA for further metabolism
22
Q
DOPA synthesis
A
phenylalanine —-phenylalanine hydroxylase or dihydrobiopterin reductase w/ BH4 –> BH2 conversion—-> tyrosine —-tyrosine hydroxylase–> DOPA
23
Q
how is whole blood prepared prior to storage? what must be considered following massive transfusions?
A
mixed w/ solutions containing citrate anticoagulant. will be in packed cells. massive transfusions of >5-6 L of blood (total body blood volume) in 24 hours –> chelate serum calcium –> hypocalcemia –> paraesthesia
24
Q
rx for acute mania (2)
A
(1) mood stabilizer (lithium, valproate, carbamazepine) and (2) atypical antipsychotic (olanzapine)
25
SSRI on mania?
known to precipitate manic episodes, contraindicated!
26
buproprione
mixed dopamine and norepinephrine reuptake inhibitor (DNRI) and nicotinic agonism. rx: depression and smoking addiction. risk of exacerbating mania
27
parvovirus B19 infxn vs. rubella
parvovirus B19: low-grade fever 7-10 days, bright-red "slapped" cheeks, followed by lacy rash on trunk and extremities. rubella: mild fever, discrete maculopapular rash from head to trunk/extremities.
28
parvovirus B19 in kids vs. adults
kids: low-grade fever --> slapped cheeks FACE --> lacy rash on EXTREMEITIES. adults: symmetrical peripheral arthropathy on fingers, wrist, and ankles
29
rubella characterestic.
characteristic: occipital and posterior cervical lymphadenopathy. have mild fever and discrete maculopapular rash from HEAD INFERIORLY that resolves in 3-5 days.
30
scarlet fever presentation
fever, sore throat, diffuse erythematous rash w/ numerous small papules (sandpaper-like)
31
roseola infantum
HHV 6: most often affects 6-15 months. high fever 3-5 days, followed by rash on TRUNK that spreads PERIPHERALLY
32
hand-foot-mouth disease
caused by coxsackievirus type A. fever & ulcers on tongue and oral mucosa & maculopapular and/or vesicular rash on palms and soles.
33
cheyne-stokes respiration. w/ which 2 conditions is it seen?
cyclic breathing of apnea and gradually increasing / decreasing tidal volumes. related to slow respiratory feedback loop. low CO2 levels trigger period of apnea. as PaCO2 rises, delayed response eventually triggers hyperventilation w/ overcompensation, which lowers PaCO2 such that apnea is induced. seen in (1) cardiac (advanced CHF) and (2) neurologic (stroke, brain tumor, traumatic brain injury). poor prognostic sign.
34
kussmaul breathing
deep and laboured breathing, associated w/ severe metabolic acidosis (i.e. DKA)
35
3 different types of frontal lobe syndrome (can seem contradictory)
(1) disorganized (2) disinhibited (3) apathetic
36
low AFP levels in amniocentesis
down's sydrome
37
high AFP associated w/ (4)
omphalocele, gastrochisis, mult gestation, neural tube defects
38
neural tube defects associated w/ increase in amniotic (2)
(1) AFP and (2) acetylcholinesterase
39
rheumatic heart fever cardiac manifestations (2) & age of presentation
almost always mitral valve disease (mitral regurg in first few decades of life). could also be mitral stenosis (usu present in middle age). mixed mitral disease possible.
40
common cause of mitral regurgitation in in underdeveloped countries
rheumatic heart disease; post-strep pharyngitis
41
describe initial gonadal development
embryo --> primitive gonads. Y chromosome --> gonadal differentiation into testes (SRY gene --> testes-determining factor). absence of Y --> default female gonadal development.
42
gonadal development determined by?
presence or absence of Y chromosome (SRY gene --> TDF)
43
paramesonephric (mullerian ducts)
involute in presence of MIF from sertoli cells. will become female internal genitalia (fallopian tubes / uterus) in absence of MIF.
44
mesonephric (wolffian) ducts
develop in the presence of testosterone from leydig cells --> male internal genitalia (epididymus, vas deferens).
45
external male genitalia develop in the presence of...
DHT (from testosterone from leydig cells)
46
formation of male (1) testes (2) internal genitalia (epididymis and vas deferens) (3) external genitalia (penis & prostate)
(1) SRY-gene -> TDF (2) mesonephric duct --> testosterone pro-male, MIF anti-female (3) DHT (from testosterone) on genital tubercle / urogenital sinus
47
formation of female (1) ovaries (2) internal genitalia (fallopian tube / uterus) (3) external genitalia
(1) absence of SRY on Y chromosome (2) absence of MIF from sertoli cells, maintain paramesophric duct (3) absence of DHT from testosterone from leydig cells on genital tubercle / urogenital sinus
48
in order for naked RNA molecule to induce viral protein synthesis in host cell, it must..
be able to act directly as mRNA (aka SS + RNA virus). naked single - or DS RNA are not infectious.
49
necrosis vs. apoptosis
necrosis: induced by injury. apoptosis: initiated by host organism, in response to (1) cell damage (2) age-related atrophy (3) specific stages of embryogenesis
50
3 steps of apoptosis
(1) initiation (2) control (3) destruction
51
initiation step of apoptosis (intrinsic vs. extrinsic)
(1) INTRINSIC, MITOCHONDRIALl-mediated: in response to cell damage by UV, heat, hypoxia, toxins, radiation --> trigger display or apoptotic signals like phosphatidylserine or thrombospondin (2) EXTRINSIC, RECEPTOR-initiated pathway: TNF on TNFR1 or FAS on FAS-L
52
control step of apoptosis (intrinsic vs. extrinsic)
intrinsic: bcl-2 proteins. pro-apoptotic: Bak, Bax, Bim. anti-apoptotic: Bcl-x and Bcl-2. apoptotic signals will tip forces, and change inner mitochondrial membrane, forming mitochondrial permeability transition (MPT) --> release cytochrome c and other pro-apoptotic proteins into cytoplasm. activate caspase.
extrinsic: death ligand + death receptor --> allows caspases to be brought close
53
destruction step of apoptosis
intrinsic & extrinsic path converge: caspase activation. caspase -> proteolytic enzymes that destroy cell components. contain cysteine. able to cleave aspartic acid residues (cysteine-aspartic acid-proteases). initiators activate effectors.
54
intrinsic apoptotic signal expression (2)
(1) phosphatidylserine (2) thrombospondin
55
2 ways of triggering extrinsic apoptosis
(1) TNF + TNFR1 (2) Fas & Fas-L
56
intrinsic anti-apoptotic factors? pro-apoptotic?
anti-apoptotic: Bcl-x and Bcl-2. pro-apoptotic: Bak, Bax, and Bim
57
what to metalloproteinases contain? what do they degrade (3)
contain zinc. degrade components of ECM (collagen, laminin, fibronectin) tissue remodeling and wound healing.
58
symptoms of toxic shock syndrome (early and late)
fever, vomiting, diarrhea, muscle pain, erythrodema. rapidly progress to severe hypotension and multisystem dysfxn. desquamation on palms and soles can occur 1-2 wk after onset. usu s. aureus.
59
pathogenesis of streak ovaries in turner (45 XO)
ovaries develop normally in fetal life (lack SRY on Y chrom), but lack of paternal X chromosome causes loss of follicles by age 2. puberty --> develop normal pubic hair, but fail to undergo breast development or menarche due to ovarian failure.
60
elevated levels of LH and FSH are characteristic of..
turner 45 XO
61
turner syndrome 45 XO presentation
short stature, shield-chest (broad w/ widely spaced nipples) webbed neck (broad neck w/ low hairline). lymphedema. cardiovascular malformations: coarctation of aorta, biscuspid aortic valve, aortic dissection in adulthood.
62
vaginal adenosis
replacement of vaginal squamous epithelium w/ glandular columnar epithelium. occurs in female children of women exposed to DES (diethylstilbestrol) during pregnancy. precursor of clear cell adenocarcinoma of vagina
63
precursor or clear cell adenocarcinoma of vagina
vaginal adenosis
64
2 diff Rx options for BPH
(1) alpha-adrenergic antagonists: terazosin, tamsulosin: work on DYNAMIC component of bladder outlet obstruction; relax smooth muscle in bladder neck, prostate capsule, and prostatic urethra. preferred rx; can work within days/wks. do NOT significantly impact volume. (2) 5-alpha-reductase inhibitors: finasteride, dutasteride; reduce prostate volume. work on FIXED component of bladder outlet obstruction. inhibit testosterone --> DHT. help if prostate if large, but takes 6-12 months for maximal effect
65
phenazopyridine
urinary analgesic. symptomatic relief of dysuria, urinary frequency, urgency in UTI.
66
tadalafil
PDE-5 inhibitor. erectile dysfunction
67
tolterodine
antimuscarinic. useful in men w/ low post-void residual volume and overactive bladder symptoms (urinary freq, urgency, incontinence). do not affect prostate volume.
68
external spermatic fascia originates from..? lies deep to..?
originates from aponeurosis of external oblique abdominal muscle. deep to dartos muscle and scrotal fascia.
69
tunica albuginea
fibrous tissue that overlies corpus spongiosum and corpora cavernosa of penis
70
what is unique about type b serotype of h. influenza?
capsular serotype containing linear polymer of ribose, ribitol, and phosphate: PRP [rather than hexose]. related to virulence, prevents phagocytosis & intracellular killing.
71
unencapsulated (nontypable) H. flu
normal flora of upper respiratory tract. rarely cause disease. if does, usu sinusitis, otitis media, bronchitis.
72
which organisms make hyaluronidase (3)
staphylococci, group A strep, c. diff
73
ulnar muscular innervation (3 main groups)
(1) flexor carpi ulnaris (2) medial portion of the flexor digitorum profundus (3) most intrinsic muscles of hand
74
proximal ulnar lesion?
guyon's canal: between hook of hamate & pisiform bone
75
proximal median n. injury? distal?
proximal: supracondylar humerus. distal: carpal tunnel.
76
median n. needed for which 3 general movements?
(1) flexion of fingers (2) thumb movement (3) pronation
77
sensation to lateral forearm
branch of musculocutaneous (lateral cutaneous n.
78
damage to musculocutaneous n.
(1) loss of forearm flexion (2) loss of sensation to lateral forearm
79
most common form of congenital adrenal hyperplasia?
90% --> 21-hydroxylase deficiency (prevents conversion of progesterone ---> 11-deoxycorticosterone AND 17-hydroxyprogesterone ---> 11-deoxycortosol)
80
detection of 21-hydroxylase deficiency in females & males
(1) females: usu identified at birth, increased androgen levels --> VIRILIZATION ambiguous genitalia (fused labial folds enlarged clitoris (2) males: have normal genitalia, present later w/ SALT-WASTING or PRECOCIOUS puberty
81
diagnosis of 21-hydroxylase
high 17-hydroxyprogesterone (in cortisol path)
82
total absence of cholesterol desmolase
incompatible w/ life
83
DHT is formed in which tissues (4)
prostate gland, testes, hair follicles, adrenal glands
84
androstenedione --> dehydroepiandrosterone
3-beta-hydroxysteroid dehydrogenase deficiency. rare form of congenital adrenal hyperplasia w/ impaired synthesis of all steroid hormones.
85
class IV antiarrhythmics (i.e. verapamil) fxn by..
block Ca++ channels in AV node and pacemaker cells.
86
class II antiarrhythmics (i.e. esmolol) fxn by.. (2)
(1) slow phase IV depolarization in cells displaying automaticity (how?) (2) slow conduction in SA and AV node (decrease cAMP, decrease Ca++ currents)
87
how do digoxin and adenosine exert antiarrhythmic effects?
slowly conduction through AV node (no effect on ion flow)
88
class III antiarrhythmics (amiodarone, sotalol, ibutilide, dofetilide) [3 effects]
slow K+ efflux from ventricular myocte --> (1) prolong repolarization (2) prolong refractory period
89
adenosine as an antiarrhythmic. what can block its effects?
increase K+ out of cells --> hyperpolarize and reduce Ca++ current. very short acting. effects blocked by theophylline and caffeine
90
Mg++ as an antiarrhythmic
(1) TdP (2) digoxin toxicity
91
digoxin as an anti-arrythmic
stimulates vagus n. --> depresses SA node and conduction through AV node.. also works in CHF by blocking Na/K pump, increasing intracellular Ca++ and contractility.
92
normal post-void residual urine volume
< 50cc
93
phenylephrine
alpha-agonist (some selectivity for alpha-1). encourage trigone & sphincter to contract promotes urinary retention.
94
2 ways to treat urinary retention
1. promotion of m3 cholinergics on detrusor (bethanechol) 2. block alpha-1 on trigone and sphincter (i.e. tamulosin, prazosin)
95
which cranial tumors stain + for GFAP (3)? which do not (2)
GFAP +: (1) astrocytoma, (2) oligodendrogliomas, (3) ependymomas. GFAP - (1) neuronal origin (2) meningomas
96
most common fatal genetic disease of caucasians
cystic fibrosis
97
clinical presentation of sickle-cell anemia
exertional dyspnea (poor exercise tolerance) & pneumonia resulting in acute chest syndrome. abdominal pain & bone pain --> vaso-occlusive events in lung, spleen, and bone, respectively.
98
luteal surge is caused by... causes.
estrogen switching from negative feedback to positive feedback on LH secretion. LH surge causes ovulation.
99
after the onset of menstruation. FSH does (2)
(1) stimulates 1+ dominant follicle formation (2) estrogen secretion from granulosa cells
100
menotropin
human menopausal gonadotropin. acts like FSH. leads to formation of dominant ovarian follicle
101
rx of infertility due to anovulation
(1) menotropins (act like FSH) make dominant follicle (2) large bolus of hCG, stimulates LH surge
102
aspirin, celecoxib, diclofenac, fenoprofen, ibuprofen, indomethacin, ketorolac, piroxicam are all... rx for?
NSAIDs. commonly used for pain, arthritis, and fever. inhibit COX (1 & 2, except celecoxib)
103
role of COX 1.. which cells? COX-2?
cox-1 plays physiologic role in (1) platelets (2) GI tract. cox-2 --> sites of inflammation.
104
NSAID that does not impair platelet aggregation (as desired for pt w/ pain, fever, and hematuria)
cox-2 specific. celecoxib.
105
side effect of both traditional NSAID and COX-2 inhibitors?
fluid retension and aggravation of HTN since both COX-1 and 2 are expressed in renal tissue
106
negative effect of COX-2 inhibitors?
dereased production of PGI2 (prostacyclin), which promotes anticoagulation and vascular dilitation. results in increased risk of cardiovascular effects.
107
which cox do platelets predominately express
cox-1
108
in what forms is CO2 carried from tissue to lungs
15% as carbamate (Hb-NH-CO2), bicarbonate in plasma
109
principal cause of high RBC chloride in venous blood?
Cl- / HCO3- exchanger to maintain electroneutrality
110
2,3-DPG role
combines w/ hemoglobin, decreases its affinity for oxygen (promotes oxygen delivery)
111
can a turner 45 xo pt become pregnant?
only by in vitro fertilization w/ donor oocyte and estrogen and progesterone to maintain preg. [have normal uterus and endometrial response to estrogen / progesterone]. risky bc increased possibility for aortic dissection or rupture.
112
positive predictive value
of the people who test positive, how many are true positives. (a/a+b)
113
what epidemiological measurement changes w/ prevalence?
positive predictive value (increased prevalence, increase PPV)
114
clinical presentation of tabes dorsalis
lancinating (stabbing) pains, loss of vibratory and position sense, areflexia, and a neurogenic bladder w/ overflow incontenience. wide-based gait, positive romberg, argyll robertson pupils (damage to tectum)
115
blunt trauma to the globe causes..
orbital blowout fractures, most commonly involving the medial or inferior orbital walls (bones lining ethmoid/maxillary sinus is this)
116
clauvulanic acid, sulbactam, tazobactam
beta-lactamase inhibitors
117
anaerobe coverage above the diaphragm? below?
above: clindamycin. below: metronidazole
118
beta-lactamase producing organisms
s. aureus, h. flu, bacteroides, and other gram negs
119
why does ganciclovir work on CMV & not other herpes viruses
differences in viral DNA polymerase structure (after monophosphorylation by a virally-encoded kinase).
120
acyclovir, famciclovir, valaciclovir, gancliclovir must be..
activated by viral kinase before able to inhibit viral DNA pol
121
why doesn't acyclovir work on EBV and CMV at normal doses?
EBV and CMV do not produce the same thymidine kinase as HSV and VZV
122
symptoms of lithium toxicity
very narrow therapeutic index, toxic at >2.0mEq/L. neuromuscular excitability, irregular coarse tremors, fasicular twitching, agitation, ataxia, delerium.
123
lithium excretion
almost exclusively by kidney, handeled like sodium. (mostly PCT)
124
what can ppt lithium toxicity (2)
anything that alters GFR or electrolyte change leading to increase PCT reabsorption. (1) VOLUME depletion (i.e. GI loss, decompensated CHF, cirrhosis) can do this. (2) thiazide diuretics (not loop), ACE inhibitors, and NSAIDs.
125
why do thiazide diuretics increase lithium toxicity but loop diuretics do not?
impaired Na+ reabsorption at DCT (thiazide) triggers increased reabsorption at PCT (site of Li+ reabsorption). however, impaired Na+ reabsorption at loop need not increase PCT reabsorption. instead, reabsorption at DCT is increased (which doesn't impact LI+ as much)
126
what is the most effective way of acutely reducing blood lithium?
hemodialysis
127
why does hyperventilation cause neurological symptoms?
low PaCO2 decreases cerebral perfusion.
128
one way to deal w/ cerebral edema?
hyperventilate patient; reduce cerebral blood flow
129
CO2 and O2 on cerebral blood flow
- increase in CO2 from 25-100mmHg causes linear increase in CBF. - only severe hypoxia <50mmHg can cause increases in CBF
130
probenecid
decreases renal clearance of penicillins by inhibiting the tubular organic acid secretion system used to prolong action of penicillin.
131
which drug causes hemprrhagic cystitis? how can it be prevented
nitrogen mustard-based chemotherapeutic agent (i.e. cyclophosphamide or ifosfamide. metabolized by kidneys into ACROLEIN --> toxic to uroepithelial cells, cause cell death & necrosis. prevent w/ adequate hydration and MESNA (2-mercaptoethanesulfonate -- sulhydryl compound) which binds and inactivates the toxic metabolites
132
N-acetylcysteine (3 indications)
(1) acetaminophen overdose (2) mucolytic agent (3) reno-protective agent
133
ondansetron
inhibits 5-HT3 receptor, treat nausea & vomiting following chemotherapy
134
filgrastim
G-CSF analogue, stimulate proliferation & diferentiation of granulocytes in pts w/ neutropenia (i.e. after chemo)
135
dexrazoxane
iron-chelating agent that can help prevent anthracycline-induced (i.e. doxorubicin) cardiotoxicity
136
amifostine
cytoprotective free-radical scavenger agent. used to decrease cumulative nephrotoxicity associate w/ platinum-containing and alkylating chemotherapeutic agents.
137
primary spontaneous pneumothorax. cause & demographics
in someone w/o pre-existing pulmonary disease, not caused by trauma or baratrauma. results from rupture of apical subpleural blebs. may arise due to distal acinal (paraseptal emphysema) tall, thin males around 20 y/o (bc have more negative intrapleural pressures in apical lung) associated w/ smoking
138
panacinar vs. centriacinar emphysema
panacinar (alpha-1-antitrypsin) lower zones and anterior margins. centriacinar predominately upper lobe distribution (strongly linked to smoking)
139
compensatory hyperinflation
can occur in normal lung parenchyma when adjacent lung segments / lobes collapse or are surgically removed. unlikely to cause pneumothorax
140
obstructive hyperinflation
lung segment / lobe expands due to a subtotal (ball-valve) obstruction of the bronchiole / bronchus supplying it. i.e. mucus plug or bronchogenic carcinoma. unlikely to cause pneumothorax.
141
primary spontaneous vs. secondary spontaneous pneumothorax
primary --> usu rupture of apical subpleural blebs, may arise due to paraseptal emphysema (distal acinar). secondary --> other types of emphysema (i.e. centriacinar, panacinar)
142
describe spherocytes (4)
(1) 2/3 diameter of normal RBC (2) more densely hemoglobinized at periphery (3) lack a zone of central pallor (4) deeper red w/ wright stain
143
clinical manifestations of hereditary spherocytosis (3). increased risk of what (2)? diagnosis?
(1) anemia (2) jaundice (hemolysis) (3) splenomegaly. increased risk of (1) pigmented gallstones (2) aplastic crisis post-parvovirus B19 infxn. diagnose w/ peripheral smear and osmotic fragility test
144
triggers for glucose-6-phosphate dehydrogenase deficiency
oxidant stress: (1) drugs -- sulfonamide or antimalarial (2) fava beans (3) infxn, like viral hepatitis, pneumonia, typhoid.
145
peripheral blood smear of megaloblastic anemia (folate / B12 deficiency)
1. hypersegmented neutrophils 2. oval RBCs
146
thoracentesis: lower border of right & left pleura. along (1) midclavicular line (2) midaxillary line (3) paravertebral line
(1) midclavicular: 7th rib. (2) midaxillary: right; upper border of 10th. left; lower border of 10th. (3) paravertebral: 12th
147
lower border of lung lies
usu two intercostal spaces above pleural border.
148
intercostal vein, artery, and nerve lie run..
subcostal groove on the lower border of the rib
149
thoracentesis should be performed (1) above or (2) below ribs?
ABOVE! avoid damage to intercostal vein, artery, nerve.
150
thoracentesis should be performed where (1) midclavicular (2) midaxillary (3) posterior scapular
(1) midclavicular - above rib 7 (2) midaxillary - above rib 9 (3) posterior scapular - above rib 11
REVIEW!!!
151
the mutation that leads to beta-thalassemia results in..
reduced beta-chain production due to a variety of mutations affecting transcription, processing, and translation of beta-globin mRNA; often aberrant splicing of precursor mRNA or premature chain termination during mRNA translation [not related to HEME synthesis] eventually leads to insoluble alpha-tetramers that ppt within RBCs that interact w/ membrane cytoskeleton and reduce membrane stability
152
beta-thalassemia is most common in which demographic? alpha-thalasemia?
beta-thalasemia -> mediterranean descent. alpha-thalasemia -> southeast asia
153
microcytic anemia, increase hgbF, hypochromia, poikilocytes and target cells in asymptomatic pt..
beta-thal minor
154
homogenous deposition of eosinophilic hyaline material in the intima and media of small arteries and arterioles is..? caused by?
hyaline arteriolosclerosis; results from NONmalignant hypertension or diabetes.
155
formation of hyaline ateriolosclerosis? caused by?
leakage of plasma constituents across vascular endothelium & excessive extracellular matrix production by smooth muscle cells. caused by chronic/repetitive endothelial injury caused by hemodynamic stress of long-standing HTN or metabolic derangements of diabetes.
156
hyperplastic arteriolosclerosis caused by.. describe it. what is it consist of (2)
MALIGNANT htn. homogenous onion-like concentric thickening of the walls of arterioles; results from (1) laminated SMC and (2) reduplicaed basement membrane
157
true or false: parathyroid cancer is a common cause of primary hyperparathyroidism
FALSE. it is very uncommon. primary hyperparathyroidism is caused by parathyroid adenoma 85% of time. parathyroid hyperplasia in other 15%.
158
which bones are common affected in hyperparathyroidism.
cortical (or compact) bone in appendicular skeleton (pectoral girdle, pelvic girdle, and limbs)
159
characterestic feature of hyperparathyroidism
subperiosteal thining
160
granular "salt-and-pepper- appearance of skull, subperiosteal erosions in the medial side of the 2nd and 3rd phalanges of the hand
radiological features of hyperparathyroidism
161
cardinal clinical manifestations of hyperparathyroidism
bone loss, renal stones, GI upset (ulcers), and psychiatric disorders (bones, stones, groans, and psychiatric moans)
162
trabecular thinning w/ fewer interconnections is characteristic of..
osteoperosis
163
excessive unmineralized osteoid and widened osteoid seams
characteristic of vitamin D deficiency
164
mosaic pattern of lamellar bone w/ irregular sections of lamellar bone, linked by cement lines
Paget's disease of the bone (cement lines represent previous areas of bone resorption)
165
osteopetrosis (cause, classic characterization)
"marble bone disease" caused by decreased osteoclastic bone resorption. persistence of primary, unmineralized spongiosa in the medullary canals. [normal individuals, bone marrow replaces primary spongiosa[
166
subperiosteal thinning is a characterestic feature of..
hyperparathyroidism
167
how is Creutzfeld-Jakob disease obtain
sporadic or infectious
168
three ways of getting iatrogenic Creutzfeld-Jakob
contaminated corneal transplants, implantable electrodes, or preparation of growth hormone
169
fatal familial insomnia
form of prion disease
170
4 common features of prion disease
(1) abnormal PrP which is resistant to enzymatic digestion (2) long incubation periods, but rapidly progressive after onset of symptoms (3) spongiform encephalopathy w/ cytoplasmic vaculoes in neutrophils and neuron --> cysts. no inflammation. (4) no RX: DEATH
171
neurosyphillis (2)
(1) progressive dementia (2) generalized paralysis
172
tissue findings of creutzfeld-jakob disease
multiple vacuoels in GRAY MATTER (spongiform encephalopathy) bc in cytoplasm!
