Syndromes
Name the four types of syndromes that can arise from single doses of whole body irradiation
prodomal
hematological
GI
neurovascular
Where do late tissue responses occur?
in organs whose parenchymal cells normally divide infrequently and do not express mitosis-linked death until later when called upon to divide
When do acute tissue responses start in relation to RT.
within 3 months of starting treatment
occurs at doses greater than 2Gy (Radbio book); 50cGy (Rad. Prot. Phy PP) humans will
develop early nausea and vomiting within hours of irradiation
4-7Gy
Which syndrome occurs after large doses of radiation (greater than 20 Gy) and results in rapid death?
neurovascular syndrome
True or false: Predictive assays are not useful in identifying patients who are at greater risk of experiencing RT side effects.
false: they are useful to identify patients at greater risks of RT side effects
At what dose does erythema begin?
Define acute tissue responses
occur mainly in tissues that renew themselves and have been related to death of critical cell populations
How can death be prevented from hematopoietic syndrome?
BMT (bone marrow transplant) and cytokine therapy.
At what doses does hemtopoietic syndrome occur?
2-8 Gy (Radbio book)
1Gy-10Gy(Rad. Prot. Phy. PP)
True or false: The volume of tissue/organ irradiated plays an important role in its response to radiation
True
At what dose does moist desquamation/ulceration start?
At doses of 20-25Gy
Define late tissue responses
occur in organs whose parenchymal cells normally divide infrequently and do not express mitosis-linked death until later when called upon to divide
Name 3 cells/tissues radiation-induced apoptosis has also been detected in
lymphoid, thymic, hematopoietic cells, sperm, and intestinal crypts
How is prodomal syndrome controlled?
with 5-hydroxytryptamine antagonists
Late responses are regarded as those that occur more than how many months after treatment?
more than 3 months
True or false: Acute radiation responses do not occur in tissues that renew themselves.
false: They mainly occur in tissues that renew themselves
Define hematopoietic syndrome
it is caused by severe depletion of blood elements due to killing of bone marrow cells
Neurovascular syndrome death is a result of ______ and _____ _____
cardiovascular and neurological dysfunction
about one week after irradiation due to severe damage to the mucosal liningof the GI tract
the tissue involved (and can be
expressed as diminished organ function)
Radiation-induced cell death in normal tissues occurs when cells attempt _____
mitosis
Define GI syndrome
Two examples of acute tissue responses are
1. Stem cells in the crypts of the small intestine
2. Bone Marrow