Chemistry Flashcards
1
Q
function of C-peptide
A
distinguish exogenous from endogenous insulin
2
Q
↑↑ insulin and C-peptide
A
insulinoma
3
Q
gestational DM fasting glucose
A
> 95
4
Q
4 criteria for DM
A
- A1C >6.5%
- fasting glucose >126
- 2-hour post load glucose >200
- random glucose >200 + symptoms
5
Q
glycolysis reduces glucose in a sample by 5-7% per hour
solution?
A
separate red cells from plasma within 2 hours
sodium fluoride tube
6
Q
2 main glucose methodologies
A
glucose oxidase
hexokinase (reference method)
7
Q
CSF glucose
A
60-70% plasma
8
Q
facilitate absorption and transport of cholesterol
A
micelles
9
Q
the more dense the lipoprotein, the (larger/smaller) it is
A
smaller
10
Q
“address tags” to tell the lipoprotein where to go in the body
A
apolipoproteins
11
Q
lowest density lipoprotein
transports triglycerides from intestines
A
chylomicrons
12
Q
lipemic plasma which separates out to a creamy layer
A
chylomicrons
13
Q
lipemia plasma which does not separate out
A
VLDL
14
Q
Independent, causal risk factor for atherosclerosis
Highly heritable.
A
lipoprotein (a)
15
Q
triacyl hydrolase (lipase) + glycerophosphate oxidase
A
triglycerides methodology
16
Q
measure HDL in samples which have been…
A
ultracentrifuged to remove VLDL and LDL
17
Q
Friedewald formula for calculating LDL
A
LDL = total cholesterol - (HDL + TG/5)
cannot be used if TG >400
18
Q
- ↑ waist circumference
- ↑ triglycerides
- ↓ HDL
- ↑ BP
- ↑ blood glucose
A
metabolic syndrome
19
Q
UV, visible and infrared spectrum
A
UV < visible (380-750 nm) < infrared
20
Q
changes the critical angle of light
A
solutes/particles in urine
refractometry
SG
21
Q
Beer’s law
A
A = abc
A = absorbance
a = absorptivity
b = light path (1 cm)
c = concentration (g/L)
22
Q
5 parts of a spectrophotometer
A
- A stable source of radiant energy
- A device that isolates a specific region of the electromagnetic spectrum
- A sample holder
- A photo detector
- A read-out device
23
Q
fulminate peptic ulcers
large amounts of gastric hypersecretion
non-β-islet-cell tumors of the pancreas
A
Zollinger-Ellison syndrome
24
Q
2 causes of PUD
A
- Helicobacter pylori
- NSAIDs
25
oral lactose tolerance test for lactase deficiency positive
unchanged blood glucose
↑ stool glucose
26
large amounts of serum proteins pass into the bowel lumen and ultimately into the feces
protein-losing enteropathy
27
transmural inflammation of the G I tract
unknown etiology
Crohn's disease
28
Celiac results from a(n) .......... response to the dietary ingestion of gluten-containing grains such as wheat
inappropriate T-cell-mediated immune
29
Arise from enterochromaffin cells of the GI tract
well-circumscribed, round, submucosal lesions
carcinoid tumors
30
Gliadin antibodies (IgA & IgG)
IgA-anti-tissue transglutaminase antibody (TTG)
IgA-endomysial antibody
celiac disease tests
31
test for PLE
Alpha-1-antitrypsin
protein electrophoresis (↓ albumin)
32
↑ fasting serum gastrin
Zollinger-Ellison
33
Whole-body scan after oral selenohomocholyltaurine (SeHCAT)
Measurement of 7α-hydroxy-4-cholesten-3-one
Bile salt malabsorption
34
parts of transferrin
apotransferrin-Fe+3 complex
35
Iron overload without associated tissue injury
hemosiderosis
36
bronzing
cirrhosis
DM
hereditary hemochromatosis
37
serum iron + ------- = TIBC
UIBC
38
heme → ------------ → unconjugated bilirubin
biliverdin
39
uridine diphosphate-glucuronyl transferase (UDPGT)
enzyme used to conjugate bilirubin
40
reduces conjugated bilirubin to urobilinogen and stercobilinogen
bacterial action
41
chalky white stool
post-hepatic jaundice
42
Least serious of the inherited unconjugated hyperbilirubinemia and the most common
Gilbert's syndrome
43
Children are born with a decreased or absolute lack of UDP-glucuronyl transferase.
Crigler-Najjar Syndrome
44
most common cause of unconjugated bilirubinemia
neonatal jaundice
45
fatal complication of neonatal jaundice
kernicterus (neurologic damage)
46
Caused by 6 months to a year of moderate alcohol consumption and results in very few lab abnormalities.
alcoholic steatohepatitis
47
The Child-Turcotte-Pugh system is the most common.
cirrhosis staging system
48
Autosomal recessive disorder of copper metabolism
Kayser-Fleischer rings
Wilson disease
49
Jendrassik-Grof
diazo reagent
blue-green
bilirubin methodology
50
Berthelot reaction
Glutamate dehydrogenase
ammonia methodology
51
The velocity is directly proportional to the substrate concentration.
first-order kinetics
52
The reaction rate is independent of substrate concentration because all enzyme is saturated
zero-order kinetics
53
Inhibitor is structurally different than the substrate and binds to an allosteric site on the enzyme molecule.
noncompetitive inhibition
54
When an inhibitor binds to the E S complex to form an enzyme-substrate inhibiting complex that does not yield product.
uncompetitive inhibition
55
relative CK index and interpretation
RI = 100(CK-MB)/total CK
<5% — crushing injury
>5% — myocardial injury
56
2 > 1 > 3 > 4 > 5
LD ratios in healthy person
57
LD1 and LD2
heart
58
LD3
lungs
59
LD4 and LD5
liver and muscle
60
LD1 > LD2
MI
61
measure the interconversion of NAD+ to NADH at 340 nm
LD methodology
62
Wacker
Wroblewski
LaDue
LD methodologies
63
function of BNP/NTproBNP
detecting congestive heart failure
64
Measuring blood levels of ---------- provides better risk assessment for heart disease than measuring any other biomarker.
hs-CRP
65
Marked elevations of ------ and ------ are associated with hepatocellular disease or damage to hepatocytes.
AST
ALT
66
Marked elevation of ------ and ------- is associated with hepatobiliary disease or obstructive liver disease.
ALP
GGT
67
liver enzyme of little value due to lack of tissue specificity.
AST
67
De Ritis Ratio & interpretation
AST/ALT
>1 — alcoholic liver disease
<1 — viral hepatitis
68
69
ALT elevation
- hepatobiliary disease
- Paget's disease/bone disease
Distinguish using GGT; elevated in hepatobiliary disease.
70
Most sensitive indicator of alcoholic liver disease
GGT
71
Useful with ALP and GGT results in determining whether ALP elevation is from bone or liver disease.
5’-Nucleotidase (5’-NT, NTP)
72
increased in acute pancreatitis, obstructive liver disease, acute alcoholism, and other conditions that affect the pancreas
amylase
73
Maltotetraose reaction
amylase methodology
74
Important in screening for cystic fibrosis and chronic pancreatitis
trypsin
75
↑ ACP (acid phosphatase)
benign prostate hypertrophy (BPH) and prostate surgery
76
phosphatase used in investigating rape
ACP
77
Ochronosis
Darkening of the tissues of the body because of the excess homogentisic acid (alkaptonuria)
78
sensitive marker of poor nutritional status such as protein-energy malnutrition (PEM)
Prealbumin/Transthyretin
79
60% of serum protein
albumin
80
A/G ratio & normal
albumin/globulins
normal — 1.1-2.5
81
In nephrotic syndrome, increased up to 10 times normal because it is retained while smaller proteins are excreted in the urine
alpha 2 macroglobulin
82
biuret method
total protein
83
Bromocresol green
Bromocresol purple
albumin methodologies
84
protein electrophoresis sample
serum — avoid fibrinogen peak
85
MM antibody classes
IgG or IgA
86
MM CRAB
- hypercalcemia
- renal insufficiency
- anemia
- bone lesions
87
Malignant proliferation of plasmacytoid cells producing IgM
Waldenstrom's macroglobulinemia
88
mainly albumin in urine
glomerular proteinuria
89
all proteins in urine
tubular proteinuria
90
normal BUN:creatinine ratio
12:0 to 20:1
91
Berthelot’s reaction
BUN methodology
92
urease + Na nitroprusside
Berthelot’s reaction
BUN methodology
93
Nessler’s reaction
BUN methodology
94
Diacetyl or Fearon Reaction
BUN methodology
95
proportional to the muscle mass of the individual and it is released into the body fluids at a constant rate
creatinine
96
Jaffe reaction
alkaline picrate
creatinine methodology
97
major product of purine (adenine and guanine) catabolism
uric acid
98
Phosphotungstic acid
allantoin
uric acid methodology
99
creatinine clearance
CrCl = (urine conc)(urine volume in ml/min)/(plasma conc)
100
creatinine clearance corrected for body mass
CrCl = (UV/P)(1.73/BSA)
101
inability to make ammonia produces an --------- urine
alkaline
(blood is acidic)
102
Hamburger shift
Cl- and HCO3- "trade places" in the RBC to keep the pH correct
103
Henderson-Hasselbalch Equation for blood pH
pH = 6.1 + log[HCO3/(pCO2)(0.03)]
104
normal blood pH
7.35-7.45
105
normal blood HCO3
22-26 mmol/L
106
normal blood pCO2
35-45 mmHg
107
accounts for about 80% of buffering capacity
hemoglobin
108
acidemia (increases/reduces) Hgb affinity for O2
reduces
muscle environment
109
normal pO2
85-108 mmHg
110
↓ pH
↓ bicarb
N pCO2
uncompensated metabolic acidosis
111
fully compensated
pH is normal, but bicarb and CO2 are both out
112
blood gas sample requirements
Arterial specimen tightly stoppered
Heparinized syringe
On ice
No air bubbles
Perform ASAP
113
methodology using the Nernst equation
potentiometry
114
anion gap & normal
anion gap = (Na + K) - (Cl + HCO3)
normal — 10 - 20 mEq/L
anion gap = (Na) - (Cl + HCO3)
normal — 7 - 16 mEq/L
115
effects on boiling and freezing points as osmolality increases
Boiling point is elevated
Freezing point is depressed
116
calculated osmolality
mOsm/kg = 1.86(Na) + (glucose/18) + (urea/2.8) + 9
117
normal serum osmo
275-300 mOsm/kg
118
osmo gap
osmo gap = measured osmo - calculated osmo
normal — approx. 0
119
effects of angiogensin, aldosterone, ADH on NaCl & water
angiotensin, aldosterone: ↑ NaCl and water reabsorption
ADH: ↑ water reabsorption
120
effects of BNP, urodilatin on NaCl & water
inhibits reabsorption
121
RAAS works to -------- BP
increase
122
↑ ADH
↓ water output
↑ water retention
SIADH
123
reduces excretion of urine by reabsorbing the water back into the body
ADH
124
ADH deficiency
diabetes insipidus
125
2 types of DI
- nephrogenic — does not respond to ADH
- central — does not produce ADH
126
Increased urine output >2.5L/day
Urine is diluted, low specific gravity, low urine osmolality
Crave water/ice
DI
127
Low serum osmolality
Fluid overload (weight gain)
Hyponatremia, with continued sodium excretion
Low urine output with high specific gravity
SIADH
128
>25 osmo gap
suspect ingestion of toxic substances
129
stimulate and promote cellular growth, differentiation, and survival
trophic hormones
130
used by the hypothalamus to stimulate the pituitary
releasing factor (hormone)
131
hormone overproduction is not suppressed by feedback inhibition
gland autonomy
132
used to document hyposecretion of hormones
stimulation tests
133
used to document hypersecretion of hormones
suppression tests
134
Hormonal disorder of middle-aged persons marked by elongation and enlargement of bones of the extremities and certain head bones
acromegaly
135
Elevated levels of GH occurring before long-bone growth is complete
pituitary gigantism
136
2 catecholamine-producing tumors of the adrenal gland
pheochromocytoma and neuroblastomas
137
↑ VMA
↑ Urinary Catecholamines
Normal Dopamine
Normal HVA
pheochromocytoma
138
↑ VMA
↑ Urinary Catecholamines
↑ Dopamine
↑ HVA
neuroblastoma
139
collection for catecholamine measurement
**24 hour urine** properly collected and preserved with **hydrochloric acid** to maintain acid pH, stored at **-80°C**
blood in **heparin** or **EDTA** tubes on **ice**, centrifuged at **4°C**, plasma stored at **-80°C**
140
primary hypersecretion of hormone
main hormone ↑
tropic hormone ↓
141
secondary hypersecretion of hormone
main hormone ↑
tropic hormone ↑
142
primary adrenal hyposecretion
Addison's disease
143
profound fatigue, weakness, weight loss, hypoglycemia, hyperpigmentation, hypotension, and hyperkalemia
Addison's disease
144
Destructive events in the hypothalamus or pituitary gland that result in a decreased ability to secrete ACTH or CRH
secondary or tertiary adrenal hyposecretion
145
Cosyntropin Synacthen
used in ACTH stimulation tests
146
Assesses the pituitary reserve and is useful for differential diagnosis of adrenal insufficiency
Metyrapone Stimulation
147
secondary adrenal hypersecretion
Pituitary is stimulated to release increased amounts of ACTH
Cushing's disease
148
primary adrenal hypersecretion
Elevated levels of cortisol due to either medications or the presence of an adrenal tumor (adrenal adenoma)
Cushing's syndrome
149
17-OHCS test (urine)
Cushing's
150
Dexamethasone Suppression Test
Cushing's
151
adrenal hyperplasia with deficient synthesis of cortisol
Congenital Adrenal Hyperplasia (CAH)
152
Two main causes of autonomous hypersecretion of aldosterone
Conn’s syndrome
Idiopathic hyperaldosteronism
153
most reliable way to diagnose primary hyperaldosteronism
Adrenal bilateral vein catheterization and measuring serum aldosterone
154
Moonface
Buffalo Hump
Facial acne
Hirsutism
Purple Abdominal Striae
Bruises and petechiae
Osteoporosis
Edema
Thin skin
Cushing's
155
deficiency of GnRH during embryonic development in both males and females. Characterized by hypogonadism and lost sense of smell (anosmia).
Kallman's syndrome
156
XXY chromosomes (47 karyotype), infertile, small testicles, sparse facial and body hair, reduced muscle mass, and enlarged breasts
Klinefelter's syndrome
157
55 X karyotype
Turner's syndrome
158
46 XX or XY karyotype
pure gonadal dysgenesis
159
infertility, hirsutism, obesity, irregular vaginal bleeding, and acanthosis nigricans
PCOS
160
Molar tissue is a developmental anomaly of the placenta that has the potential for malignant growth
hydatidiform mole
161
LH:FSH ratio >2:1
no menstural cycle
PCOS
162
no estrogen
increased LSH and FSH
menopause
163
most common cause of hypothyroidism
Hashimoto's
164
most common cause of hyperthyroidism
Grave's disease
165
Exophthalmic eye (Eye bulging)
Tremors
Weight Loss
Graves' disease
166
thyroid peroxidase +
Hashimoto's
167
thyroid receptor antibody +
Grave's disease
168
goiter
Hashimoto's
169
phylloquinone
vitamin K assay
170
Beriberi, Wernicke-Korsakoff syndrome
B1 (thiamine) deficiency
171
Pellagra
B3 (niacin) deficiency
172
Rickets
vitamin D deficiency
173
PTH and vitamin D3 ----- serum iCa and ------ Phos
↑
↓
174
should be measured with iCa
pH; inverse relationship
175
sample for intraoperative PTH
K3-EDTA
176
CEA
GI, pancreatic, lung, breast malignancies
177
CA 15-3
breast, ovarian malignancy
178
CA 549
breast malignancy
179
CA 27.29
breast malignancy
180
CA 125
ovarian malignancy
181
CA 19-9
GI, pancreatic, hepatic malignancies
182
CA 242
GI, pancreatic malignancies
183
protooncogene p53
breast, colorectal, lung, liver malignancies
184
therapeutic drugs run on WB
Cyclosporine & Tacrolimus
185
Structural analog of phenobarbital
primidone
186
major metabolite is NAPA
procainamide
187
Alkaloid obtained from the bark of the cinchona tree
quinidine
188
signs of adulterated urine
* pH <3 or ≥11
* Nitrite concentration ≥ 500 ug/mL
* Presence of chromium (VI)
* The presence of halogens (bleach, iodine, fluoride)
* The presence of glutaraldehyde
* The presence of pyridine (pyridinium chlorochromate)
* The presence of a surfactant
* The presence of any other adulterant not specified in 3-7 is verified using an initial test on the first aliquot and a different confirmatory test on the second aliquot
189
Not useful if the time of ingestion is unknown or unreliable
acetaminophen levels
190
Can cause...
Respiratory alkalosis
Uncompensated respiratory acidosis
Metabolic acidosis
salicylate poisoning
191
Represent the most widely prescribed drugs due to their principal pharmacological effects
benzos
192
Qualitative screening test in urine is designed to detect the metabolite **benzoylecgonine**
cocaine
193
Causes miosis or constriction of the pupils in most patients
methadone
194
Current biomarker for assessment is venous whole blood with or without measured fluorinated ethylene propylene (FEP).
lead
195
Competes with ethanol for alcohol dehydrogenase (ADH)
methanol
196
Calcium oxalate crystals in the urine
Increase in osmol gap
Increase in anion gap
ethylene glycol
197
measure serum **butyrylcholinesterase** (**pseudocholinesterase**) activity to diagnose acute ingestion or monitoring chronic exposure
Organophosphate and Carbamate Compounds
198
% CV =
100(SD)/mean
199
RCF =
(1.118 x 10^-5)(r)(rpm)^2
200
two etched rings at the top
blowout step on pipette
201
1 gallon = --------- liters
3.79
