1define early effects of radiation
effects of ionizing radiation that occurs within minutes hours days weeks or months of time of exposure
2what is acute radiation lethality
sequence of events following high dose radiation exposure leading to death within days or weeks
3what kind of graph does acute radiation lethality follow
non-linear, threshold dose response relationship
4what is a symptom
a collection of syndromes
5hematologic death occurs at how many rad
200-1000 rad (2-10 Gy)
6gastrointestinal death occurs at how many rad
1000-5000 rad (10-50 Gy)
7Central Nervous System death occurs at how many rad
5000 (50 Gy)
8what is minimal amount of rad lethal to humans
200 rad (2 Gy)
9How many stages are associated with radiation lethality and what are they?
4
Prodromal Period
Latent Period
Manifest Illness
Recovery/death
10At how many Rad does Prodromal Period begin and what are symptoms
100 rad (1 Gy)
Nausea, Vomiting, Diarrrhea, Leukopenia
11What is the Latent Period
Period where no effects are seen following the initial radiation sickness
12what is the manifest illness stage
Stage of acute radiation syndrome during which signs and symptoms are apparent
13what are the 3 syndromes of the manifest illness stage
Hematologic, Gastrointestinal, Central Nervous System syndrome
14what is the dose required for the hematologic syndrome?
200-1000 rads (2-10 Gy)
15How long is the latent period for Hematologic syndrome
4 weeks
16which syndrome of manifest illness is a person able to recover completely from?
hematologic
17When does death occur for hematologic or if not death how long is recovery
death @ 6-8 weeks after irradtiation, if its not lethal takes 6 mo to recover
18what happens during hematologic syndrome
reduction of WBC RBC platelets
19what happens during gastrointestinal syndrome
Sever dmg to Stem cells in lining of instestines
20how much rad is req to get gastrointestinal syndrome
1000-5000 rad (10-50 Gy)
21how long is latent period of gastrointestinal sydrome and when does death occur
3-5 days
death within 4-10 days from sever diarrhea and electrolyte imbalance
22what happens during CNS syndrome
Elevated fluid content of brain
23What is Dose rq for CNS syndrome
over 5000 rad (50 Gy)
24how long is the latent phase for CNS syndrome
latent period can last 12 hours
25upon how many rad will a victim experience latent period
immediately following 1000 rad
26how does death occur during CNS syndrome
from increased intracranial pressure, inflammatory changes in the blood vessels of the brain and meningitis in 0-3 days.
27What is LD 50/60
The whole body dose of radiation that causes 50% of the irradiated subjects to die within 60 days.
28what is the amount of rad for LD 50/60
350 rad (3.5 Gy) for humans
29what is the most radiosensitive animal
pig at 250 rad 2.5gy
30what is the most radioresistant animal
cockroach at 10,000 rad
31what is mean survival time
as radiation dose increases, the time between exposure and death decreases (inverse relationship)
32what is MST of hematologic syndrome and what is its dependecy
10-60 days
dose dependant
33what is MST of GI syndrome and its dependecy
constant at 4 days
independant of dose
34what is MST of CNS syndrome and dependency
0-3 days
dose dependent
35what is tissue damage due to radiation
an lead to atrophy and total non-function of tissues and organs in that area
36Tissue damage depends on what
Radiosensitivity
Cell Proliferation
Cell Maturity
37what response relationship does skin-effects follow
non-linear, threshold dose response relationship
38What dose until erythema
200 rad (2Gy)
39what are basal cells
stem cells
40what is SED
Skin erythema Dose
41what is SED 50
dose required to cause erythema in 50% of irradiated
42What is dose of SED 50
500 rad (5Gy) can start at 200 rad (2Gy)
43what dose can cause gonadal dysfunction
10 rad (1dGy)
44when are ovaries most radiosensitive
during fetal life and early childhood
45how many rad can supress or delay menstruation
10 rad (1dGy)
46how many rads can cause temp sterility
200 rad (2Gy)
47how many rad can cause permanent sterility
500 rad (5 Gy)
48what are oogonia
stem cells which multiply during fetal growth
49what is the most radiosensitive cell in development cycle for women
oocyte in mature follicle
50how many rads can reduce number of sperm
10 rad (1dGy)
51what is spermatogonia
stem cell and most radiosensitive cell in development process for boys
52in 1920-1930s what caused time off for techs
leukocyte reduction of 25%
53what dose does hematologic depression begin
250 mGy
54what are the lymphoid tissues
lymph node, spleen, thymas
55what does the hemopoietic system consist of
bone marrow, circulating blood and lymphoid tissues
56what do all cells of hemopoietic system develop from
pluripotential stem cell
57what does the pluripotential develop into
lymphocytes
granulocytes
thrombocytes
erythrocytes
58where and how long does granulocytes and erythrocytes develop
bone marrow for 8-10 days
59where and how long does thrombocytes develop
bone marrow 5 days
60what is lymphopenia
reduction of lmyphocites
61what is most radiosensitive cell in hemopoietic system
lymphocytes
62what is cytogenetics
study of cell genetics and cell chromosomes
63what dose is it difficult to observe aberrations
less than 5 rad
64how many chromosomes does each cell have
23
65what does chromosome aberration represent
severe damage to DNA
66what is chromatid deletion
breakage of chromatid
67what is isochromatid
fragmented piece of chromatid
68what is ring chromosome
when chromatids stick together to form a ring
69what is dicentnric chromosome
when chromatids hit more than once and recombine
70what is reciprocal translocation
when 2 chromosomes or chromatids break and exchange fragments
71what can happen to daughter cells after mitosis
one or both can miss genetic material
72what dose response relationship are single hit aberrations produced
linear non threshold
73what dose response relationship are multi hit aberrations produced
non-linear threshold
74what are the single hit chromosome abberations
chromatid deletion
75what are the multihit chromosome abberations
ring chromosomes, dicentric chromosomes and reciprocal translocations