8/23/17

Question 1

Classical conditioning

Answer 1

Neutral stimulus (CS) paired with unconditioned stimulus (UCS)

UCS elicits a natural response (UCR)

Eventually CS will elicit a conditioned response (CR), which is often similar to the UCR

Question 2

Operant Conditioning

Answer 2

Learning due to environmental contingencies of reward and punishment

Positive reinforcement: applying rewards makes behavior more likely to occur

Negative reinforcement: withdrawing aversive consequences makes behavior more likely to occur

Punishment: applying aversive consequences makes behavior less likely to occur

Extinction: withdrawing positive consequences makes behavior less likely to occur

Question 3

Challenges of Operant Conditioning

Answer 3

Shaping: progress, not perfection

Frequency of consequences (at least for positive reinforcement): continuous reinforcement to acquire, intermittent reinforcement to maintain (fading reinforcement)

Timing of consequences: close temporal link between behavior and consequence

Clarity of consequences

Question 4

Clinical Application of Operant Conditioning

Answer 4

Feeding disorder of infancy or early childhood

Question 5

Counts of Disease Frequency

Answer 5

Can’t be compared since can be from pop. of different sizes

Good if single count is useful for public health (Ebola) or for allocating resources

Question 6

Ratio for Disease Frequency

Answer 6

Shows the relative size of two values/groups

Question 7

Proportion of Disease Frequency

Answer 7

Ratio in which the numerator is a subset of the denominator

Question 8

Rate of Disease Frequency

Answer 8

Like proportion but during some period of time

Contain counts of disease frequency, size of pop. at risk, and a time period

Question 9

Incidence
Cumulative incidence
Incidence rate (density)

Answer 9

Frequency of new cases over time period, measures the appearance of diseases

Cumulative: risk of getting a disease, usually used in fixed pop. but most dynamic so bad measure 
# new cases / # originally at risk (over certain time)

Rate: # of new cases / sum of disease free person-time over a certain time period

Question 10

Point prevalence vs. Period prevalence

Answer 10

Point: # of existing cases / total pop. At a specific point in time

Period: (# of existing cases + # of cases that occur during the interval) / pop. at midpoint of interval or the average pop. size

Both are proportions

Question 11

Relationship between prevalence and incidence

Answer 11

Prevalence is similar to incidence * disease duration (P=ID)

I~P if short disease duration

Prevalence higher than incidence if chronic disease

Measure incidence if care about etiology

Question 12

Protein turnover

Answer 12

Total flux through protein synthesis and degradation

Conversion of AA pool into protein and breakdown of protein into the free AA pool

Question 13

AA precursors for N-containing compounds

Answer 13

Cys to taurine to bile salts

Tyr to thyroid hormones, melanin, catecholamines (NE, epi, dopamine)

Gly to heme, purines, creatine, bile salts

Question 14

Nitrogen balance

Answer 14

Nitrogen ingested - nitrogen excreted

At eq.: you intake 100 mg/kg/day of nitrogen or 600 protein

Positive: anabolic state to build mass, plateaus, normal growth, athletes, increased protein translation from free AA pool

Question 15

Cachexia

Answer 15

Negative nitrogen balance that accompanies chronic diseases like cancer, renal diseases, severe burns, and septicemia

Rapid weight loss of 5-20%, high catabolic state that leads to muscle loss

Need nutritional supplementation since normal nitrogen diet is still negative nitrogen balance, also use stimulation of anabolism through steroids

Protein turnover accelerated from inflammatory process

Question 16

Reductive amination

Answer 16

Glutamate-dehydrogenase with any aminotransferase can form any non-essential AA except Tyr/Cys given the proper alpha-keto acid and ammonia source

Question 17

Phenylketonuria

Answer 17

Phe is converted to Tyr by phenylalanine hydroxylase

PKU has mutated Phe hydroxylase or enzymes in tetrahydrobiopterin (it’s cofactor)

Avoid Phe in diet and supplement with Tyr, avoid aspartame

Question 18

Homocystinuria

Answer 18

Recessive, deficiency in gene for cystathionine beta-synthase

Accumulate homocysteine and Met

Free sulfhydrl of of homocysteine disrupts collagen cross linking and leads to premature atherosclerosis, strokes, heart stacks, vascular disease, ectopia lentis, and mental retardation

Avoid Met in diet and supplement with Cys

Cys becomes conditionally essential

Question 19

Cystathioninuria

Answer 19

Recessive, Cys becomes essential AA

Cystathionine accumulates, is more benign since Met and homocysteine levels are more normal

Question 20

Asparagine synthetase

Answer 20

Requires ATP

Adds NH2 to Asp to make Asn, also Gln becomes Glu by losing an NH2

Question 21

Acute lymphonic leukemia

Answer 21

Accumulate immature lymphocytes in blood, they lack aspargine synthetase and Asn becomes an essential AA

L-asparaginase hydrolyzed Asn to Asp in the plasma conc. and deprive lymphoblasts only source of Asn, lymphoblasts do apoptosis

Question 22

Most abundant AA in plasm

Answer 22

Gln which is made by glutamine synthetase from Glu

Question 23

AA absorption

Answer 23

Active transport that requires Na+ in the small intestines

Transporters:

1. Small neutral
2. Large neutral
3. Basic
4. Acidic
5. Proline

AA imbalance even if get min cuz competition at transporters

Go to liver via hepatic portal vein and then transported in the blood

Question 24

Essential AA

Answer 24

PVT TIM HALL

Arg and His are not as essential

Can’t be made in human body and need from diet

Conditional essential AA if have like PKU

Question 25

Protein Quality

Answer 25

Biological Value:
Measures the percentage of absorbed AAs retained for protein synthesis (during growth)

Depends on dietary N, urinary N, and fecal N (with endogenous values for the last two)

Net Protein Utilization:
Like BV but neglects absorption

Protein Efficiency Ratio:
No chemical analysis
Weight gain/weight of protein ingested during period of time

Digestibility:
Percentage of nitrogen absorbed, only fecal and no urinary

Chemical Score:
Mg of essential AA in test / mg in egg

Protein Digestibility Corrected AA Score:
Like chemical Score but use rigorous requirements needed for a 2-5 year old, takes digestion into account

Question 26

Kwashiorkor

Marasmus

Answer 26

Kwashiorkor: Severe protein deficiency, when stop breast feeding first born, occurs within days to weeks

Edema and distended abdomen, mental apathy, pigmentation changes, muscle wasting, high mortality

Marasmus: protein energy malnutrition over the course of months or a year, wasting of fat and muscles but mentally alert

Question 27

Benefits of fiber in diet

Answer 27

1. Reduce incidence of hemorrhoid, cardiovascular disease, hyperlipidemia, and diverticulitis
2. Promote weight loss since feel full
3. Stimulate peristalsis and prevent constipation
4. Remove cholesterol and sterols from feces
5. Help promote glycemic control and reduce hyperlipidemia for diabetics

Question 28

Glycemic index and glycemic load

Answer 28

Index: classifies carbs based on ability to raise blood sugar, use glucose as reference

Load: index * amount of carbs in grams / 100

High index/load associated with type II diabetes

Question 29

Types of Carbs and Fiber

Answer 29

Available: can be digested and absorbed for use calorically or to make other metabolic products

Basic mono and disaccharides plus stack, glycogen, and dextrins

Unavailable: largely indigestible, provide bulk in diet and help wth elimination

Insoluble like cellulose or soluble like pectins, oatmeal, and bananas

Dietary fiber: remains after breakdown in digestive tract

Crude fiber: remains after acid and alkaline digestion of food, smaller than dietary fiber

Added fiber: isolated nondigestible carbs that are added to food for good physiological benefits

Question 30

Essential FA deficiency

Answer 30

Can’t make a double bind at omega-3 or-6 so need from diet

Occurs in children, dermatitis, alopecia, growth retardation

Linoleic (18:2 w6) > linolenic (18:3 w3) > arachidonic (20:4 w6) help treat

Question 31

Characteristics of trans FA

Answer 31

Higher melting point

Increase LDL/HDL ratio

Inhibits desaturase which helps make arachidonic acid (precursor of prostaglandin)

Increase shelf life of foods

Present in fried foods

Question 32

Daily recommended intake of macronutrients

Answer 32

Carbs: 45-65%
Fat: 20-35%
Protein: 10-35%

Proteins have sparing effects where like high Cys spares lower Met since Met makes Cys and lower that conversion, complementary proteins have essential AAs when combined like beans and wheat

Have at least 2 fish per week for omega-3 FA

Question 33

Heart contraction

Answer 33

HR set by sinoatrial node, located in right atrium and discharges without control from the brain

Both atria contract, electrical impulse travels through atria to the atrioventricular node

Question 34

EKG Prep

Answer 34

Position the patient: make supine, head flat or no more than 45°, position can alter EKG so note any changes if not supine

Skin prep: use alcohol pad to de-fat where put electrodes, gently abrade skin with gauze, improve conduction and reduce noise
If oily/soiled skin- wash with soap/water and dry first, briskly rub with alcohol
If diaphoretic (sweaty)- dry with cloth first
If hairy- separate hairs or clip, try not to shave

Lead Electrode Placement: one for each limb, six for chest, make sure attached right and sticky

Question 35

Chest Leads for an EKG

Answer 35

V1: 4th intercostal space, right eternal border

V2: 4th ICS, left sternal border

V3: equidistant between V2 and V4

V4: 5th ICS at the midclavicular line

V5: at the horizontal level to V4 at the anterior axillary line

V6: horizontal level to V4 at the midaxillary line

Find 4th ICS by finding Angle of Louis at 2nd rib, count down to 4th intercostal

Question 36

Limb Electrode Placement

Answer 36

Arms: below elbow and between wrist on lower forearm

Legs: below knee and between ankle, lower leg

Placed on fleshy areas and same position for same type of limb

Question 37

3 Troubleshooting Issues for an EKG

Answer 37

1. Electrical interference: closely jagged lines from too many electronics or improper grounding

Fix: turn off all nonessential electronics and lights, check to ensure wires stent twisted, possibly switch rooms

2. Wandering baseline: bad electrode connection or exaggerated respiratory movements makes the waveform go up/down during tracing

Fix: check that electrodes are in the right spot and the skin isn’t oily/sweaty, have patient breath in and out and hold breath while run EKG

3. Somatic or muscle tremor: lines spiking and running close together, over shorter period of time than electrical interference, skeletal muscle movements like chills or Parkinson’s

Fix: cover patient if chilled, position patient’s hands under hips to quiet movement, try higher limb lead placement if movement not that exaggerated