Chapter 4 Extra

Question 1

define syndrome

Answer 1

• is used to show the relationship of the signs and symptoms to a specific type of trauma or disease process.

Question 2

What radiation exposures must happen I order for total body radiation syndrome to be applicable?

Answer 2

1. an organ must be exposed acutely (in seconds or minutes)
2. there must be exposure of the total body area
3. external penetrating sources, for example, X-rays, gamma-rays, and neutrons, produce the radiation syndromes.

Question 3

define total body radiation syndrome

Answer 3

• the response of an organism to whole body radiation results in specific findings

Question 4

what are consequences of acute radiation exposure?

Answer 4

• short-ending life span
• dose dependent
• can be very fatal

Question 5

define LD 50/30

Answer 5

• lethal dose to kill 50% of a population in 30 days

Question 6

define LD 50/60

Answer 6

• lethal dose to kill 50% of a population in 60 days

Question 7

what happens when dose increase?

Answer 7

• survival time and number of survivors decrease

Question 8

what are the 3 different types of Acute Radiation Syndrome?

Answer 8

1. Bone Marrow
2. Gastrointestinal (GI)
3. Central Nervous System (CNS)

Question 9

define bone marrow syndrome

Answer 9

• hemopoietic (development of blood cells)
  damage
• occurs within 100-1,000 R range
• death occurs between 6-8 weeks
• no one survives 1,000 R
• destruction of bone marrow -> decline production of RBC’s, WBC’s, and platelets
• death results from anemia and infection
  ^ body becomes very vulnerable from lack of protection

Question 10

define gastrointestinal (GI) syndrome

Answer 10

• damage in the gastrointestinal tract, especially the small intestine
• occurs with 600-10,00 R range
• not dose-dependent
• death happens at the same time regardless of dose
• death occurs 3-10 days w/o help, 2 weeks w/ help
• damage to villi cells creates a decline of absorption in the GI tract
• dehydration
• systemic infections
• decline of WBC’s

Death:
- infection
- dehydration
- electrolyte balance

Question 11

define the Central Nervous System (CNS) syndrome

Answer 11

• occurs in doses greater than 10.000 R
• death is within hours
• damage to blood vessels
• edema (swelling)
• vasculitis (inflammation of blood cells)
• meningitis (inflammation of spinal cord and brain membranes)
• person does not live long enough to show symptoms

Question 12

what are the 4 different types of response stages?

Answer 12

1. Prodromal
2. Latent
3. Manifest
4. Death or Recovery

Question 13

define prodromal stage

Answer 13

• NVD (nausea, vomiting, and diarrhea)
• occurs with low doses of 50 rads
• lasts a few minutes to days
• dose dependent (the higher the dose, the shorter the stage)

Question 14

define dose dependent

Answer 14

• the higher the dose, the lower the stage

Question 15

define the latent stage

Answer 15

• asymptomatic
• changes that can lead to recovery or death
• dose dependent
• weeks below 500 R -> hours/less than 10,00 R

Question 16

define the manifest stage

Answer 16

• lasts minutes to weeks
• the animal is noticeably ill and shows signs and symptoms

Question 17

What are the response stages in bone marrow syndrome?

Answer 17

Prodromal
- involves NVD
- few hours after exposure

Latent
- bone marrow stem cells are dying
- reduction of cells circulating the blood

Manifest
- reduction of cell count
- depression of blood cell count (cytopenia)
- causes anemia and infection

• leads to decline of blood cells and can lead to hemorrhage

Question 18

what are the response stages in the gastrointestinal (GI) syndrome?

Answer 18

prodromal
- happens within hours
- NVD
- cramps

Latent
- occurs on the 5th day
- NVD occurs again
fever

Manifest
- 5th to 10th day
- GI tract, especially the small intestine is damages by doses in radiation

• death occurs from dehydration, infection, and electrolyte imbalance

Question 19

define Crypts of Lieberkuhn

Answer 19

• radiosensitive cells that are precursor to the population of villi cells
• in the GI tract

Question 20

what are the response stages in the Central Nervous System (CNS) syndrome?

Answer 20

prodromal
- NVD
- confusion
- loss of consciousness
- burning sensation of the skin

Latent
- lasts several hours

Manifest
- 5-6 hours
- results in diarrhea, convulsions, coma and death

• person dies due to the damage of blood vessels

Question 21

define atrophy

Answer 21

• shrinking of the tissue or organ

Question 22

define local tissue damage

Answer 22

• atrophy may occur
• leads to an organ or tissue to not function properly
• tissue response depends on radiosensitivity, reproduction, and maturation rates
• Ex.) skin, eyes, gonads

Question 23

define skin tissue damage

Answer 23

• inflammation
• erythema (100-10,000 rads)
• desquamation
• basal layer cells are radiosensitive
• with moderate doses, skin can regenerate
• with high doses, it can lead to atrophy, fibrosis, pigment changes, etc.

Question 24

define SED

Answer 24

• skin erythema dose
• the necessary amount of SED to affect 50% of the people is approx. 600 rads (6 Gy)*

Question 25

what dose -response relationship does skin erythema have?

Answer 25

- nonlinear; threshold

Question 26

are hair follicles radiosensitive or radioresistant?

Answer 26

- radiosensitive - since they're growing tissues, they're radiosensitive - moderate dose = temporary alopecia/epilation - high dose = permanent epilation

Question 27

define radiation cataractogenesis

Answer 27

- formation of cataracts by radiation

Question 28

whats the dose-response relationship for eyes?

Answer 28

- threshold; nonlinear

Question 29

what are some precautions with gonads?

Answer 29

- they are highly radiosensitive - doses as low as 10 rad can cause observable responses

Question 30

define mature depletion

Answer 30

- damage and reduction in the number of spermatogonia, leading to the depletion of mature sperm