Ch10: Environmental Pathology Flashcards Preview

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Flashcards in Ch10: Environmental Pathology Deck (252):
1

What are three major determinants of our health?

1. Air we breath
2. Food and water we consume
3. Exposure to toxic agents

2

What is an environmental disease?

Condition caused by exposure to chemical or physical agents in a person's environment

3

What is overall fatality rate of occupational injuries?

4.8 per 100,000 workers

4

Who set the standard for reporting health information?

Global Burden of Disease

5

What is the GBD statistic for assessing premature mortality and disease morbidity?

DALY (Disability adjusted life year)

6

What is the DALY statistic?

adds the years of life lost to premature mortality with the years lived with illness and disability.

7

What is said to increase due to human activity in regards to climate change?

1. CO2
2. Methane
3. Ozone

8

Causes of increased CO2? (2)

1. Combustion of hydrocarbons in automobiles and energy plants
2. Deforestation

9

Problems with human health in regard to climate change? (4)

1. CV, Cerebrovascular, Respiratory disease
2. Gastroenteritis and infectious disease
3. Vector-borne infectious diseases
4. Malnutrition

10

What is the definition of poison?

A dose that causes harmful effects instead of helpful

11

How many pounds of carinogenic toxic chemicals are released per year in the US?

4 billion pounds

12

What 4 agencies determine exposure limits?

EPA
FDA
OSHA
CPSC

13

The EPA regulates what?

Exposure to peticides, toxic chemicals, water and air pollutants

14

The FDA regulates what?

drugs, medical devices, food additives, and
cosmetics

15

What does OSHA mandate?

employers provide safe working conditions for
employees

16

What does CPSC regulate?

other products sold for use in homes, schools, or
recreation

17

What are xenobiotics?

Exogenous chemicals in the air, water, food
and soil that may be absorbed into the body
through inhalation, ingestion, and skin contact

18

Where do xenobiotics act? (2)

Site of entry
Transported to distant tissues by BV's

19

What xenobiotics are metabolized to form inactive water-soluble products or activated to form toxic metabolites? 2

Solvents
Lipophilic drugs

20

Most important catalyst of phase I reactions is what?

Cytochrome p450 system

21

Carbon tetrachloride is metabolized to what in the liver?

Toxic trichloromethyl free radical

22

Benzo-alpha-prene is metabolized to what?

DNA-binding metabolite carcinogen

23

Xenobiotics are typically eliminated how?

Phase I reaction
Phase II reaction to soluble metabolite
Eliminated from body

24

What does Radon cause?

Lung disease and cancer

25

EPA has limits for what 6 pollutants?

1. Ozone
2. Nitrogen oxides
3. Sulfur dioxide
4. Particulates
5. CO
6. Lead

26

Smog is what?

Smoke and fog

27

What leads to formation of ozone layer?

Interaction of UV radiation and oxygen in the stratosphere

28

Why is the ozone layer good?

Absorbs the most dangerous UV from sun

29

What causes ozone layer loss?

Halocarbons like CFP's

30

Toxicity of ozone is due to what?

Production of free radicals that injury lung epithelial cells and Type I alveolar cells

31

How does ozone cause release of inflammatory mediators?

Oxidizes lipids to H2O2 which acts as irritant

32

Overall effect of ozone on lungs? (3)

1. Increase epithelial permeability
2. Increased reactivity of airways
3. Decreased ciliary clearance

33

Nitrogen dioxide does what in the airway?

Dissolves in water to form nitric acid which damages airway epithelium

34

Sulfur dioxide is produced by who? 2

Power plants burning coal and oil
Byproduct of mills

35

SO2 is absorbed in airways where it releases what? (3)
Effect of this?

H+, HSO- (bisulfite), SO3 (sulfite)
Local irritation

36

Particulate matter like soot is most hazardous at what size?

Ultrafine (<10 um)

37

What is effect of ultrafine soot in lungs?

Phagocytosed by macrophages which causes release of inflammatory mediators that damage lungs

38

What is anthracosis?

Black pigment in lungs

39

3 main effects of soot in lungs?

1. Cytokine release systemically
2. Increased blood viscosity
3. Autonomic changes affecting the heart

40

Carbon monoxide has what four characteristics?

1. nonirritating
2. colorless
3. tasteless
4. Odorless

41

What produces CO?

Incomplete oxidation of carbon materials

42

Greatest danger of CO toxicity is when?

Working in confined environments with high exposure (in a garage will kill in 5 minutes)

43

Carbon monoxide effects? 2

1. CNS depressant
2. Binds to hemoglobin causing loss of oxygen

44

Severe hypoxia occurs when with CO?

20-30% saturation

45

Death and loss of consciousness occur when with CO?

60-70 percent saturation

46

Indoor air pollution includes? (4)

1. tobacco smoke
2. CO
3. NO2
4. Wood smoke (NO's, soot, hydrocarbons)

47

Formaldehyde is found in what especially?

New carpet

48

Radon is a decay product of what?

Uranium and is found in soil

49

Asbestos fibers are found where?

Houses built before 1970

50

Bioareosols are used for what?

Aerosolization of bacteria

51

What is the famous bioaerosol exposure?

Legionella pneumophilia

52

Lead exposure occurs through what? 3

Air, food and water

53

Most absorbed lead goes where?
What does it compete with?
How is it seen radiographically?

Bone and teeth

Calcium

Lead lines along growth plates

54

Is acute poisoning of lead common?

No.

55

Acute Lead poisoning is seen with what main symptoms? 2

Neurologic symptoms
GI symptoms

56

Why are children affected more than adults by lead?

1. Absorb 50% of ingested lead compared to adults' 15%
2. More permeable blood brain barrier

57

Which nervous system is affected more in children?
More in adults?

Children = CNS
Adults = PNS

58

How does lead present in terms of blood?

Microcytic anemia with coarse basophilic stippling

59

When will you see the microcytic anemia with coarse basophilic stippling in lead toxic patients?

At 40 ug/ml

60

Arsenic intereferes with what?

Cellular longevity by interfering with oxidative phosphorylation

61

Signs and symptoms of acute arsenic poisoning?

1. HA
2. Confusion
3. Convulsion
4. Diarrhea
5. Vomiting
6. Neuropathies

62

Long term exposure to arsenic leads to what?

Night blindness due to Vitamin A deficiency

63

3 cancers caused by long term arsenic exposure?

1. Cutaneous basal cells
2. Squamous cell
3. Lung carcinomas

64

Cadmium is generated where? 2

Mining
Cadmium nickel batteries

65

Toxicities of cadmium include what? 4

1. Obstructive Lung disease
2. End stage renal disease
3. Skeletal problems
4. Lung carcinomas

66

Three main forms of mercurcy?

1. Elemental
2. Inorganic: Mercury chloride
3. Organic: Methyl mercury

67

Modern sources of mercury? (4)

1. Contaminated sea food
2. Dental
3. Gold mining
4. industry

68

Clinical manifestation of mercury? 4

1. Nervous system: CNS malfunction and peripheral neuropathies
2. Kidney injury
3. Tremors/bizarre behavior
4. Gingitivitis

69

What is methyl mercury particularly toxic to?

Developing CNS

70

Chronic exposure of mining and industrial chromium and nickel has what effect?

Increased nasal and lung carcinomas

71

Cause of heart disease? (4)

1. CO
2. Lead
3. Solvents
4. Cadmium

72

Cause of nasal cancer? 2

1. Isopropyl alcohol
2. Wood dust

73

Cause of lung cancer? 7

1. Radon
2. Asbestos
3. Nickel
4. Arsenic
5. Chromium
6. Mustard gas
7. Uranium

74

Cause of COPD? 2

1. Dust
2. Cadmium

75

Cause of respiratory irritation? 3

1. ammonia
2. sulfur oxide
3. formaldehyde

76

Cause of fibrosis in respiratory?

1. Asbestos

77

Organic solvents are readily obsorbed where? 2

Skin
Lungs
GI

78

Organic solvent acute exposure can lead to what?

CNS depression/Coma

79

Huffing involves inhalation of what?

Organic solvents

80

Benzene is metabolized by what?
What do its metabolites cause? (3)

Cytochrome p450

1. Bone marrow toxicity
2. Leukemia
3. Aplastic anemia

81

Polycyclic aromatic hydrocarbons are composed of what?

Aromatic rings in a flat plane

82

PAH's are found in what? 4

Foundries
Tars
Soot
Tobacco smoke

83

What are PAH's considered?

Most potent chemical carcinogens

84

PAH's are so potent why?

Very common and highly carcinogenic

85

Industrial exposure to PAH's is linked to what? 2

1. Bladder carcinoma
2. Lung carcinoma

86

Organochlorines are lipophilic products that can resist what?

Degradation

87

Organochlorines have what type of activity?

Anti-estrogenic and Anti-Androgenic leading to decreased fertility rates

88

What are most organochlorines used for?

Pesticides

89

Non-pesticide organochlorines are known to cause what? 4

1. Chloracne
2. CNS probs
3. Hepatic probs
4. Induce cytochromes

90

What is chloracne?

Hyperpigmentation and hyperkeratosis of face and ear

91

Vinyl chloride is used to produce what?

Polymer polyvinyl chloride (PVC)

92

What will vinylchloride cause?

Anglosarcoma of liver

93

Mineral dust inhalation causes what?
4 Examples?

Chronic, non-neoplastic lung disease "Pneumoconioses"

1. Black lung
2. Silicosis
3. Asbestosis
4. Berylliosis

94

What is the most preventable cause of human death?

Smoking tobacco

95

How many people die due to tobacco smoke in US a year?

440,000

96

What are the causes of death in smokers? (10)

1. Lung cancer
2. Esophageal cancer
3. Bladder cancer
4. Oral cavity/URT cancer
5. Pancreatic cancer
6. Athersclerosis
7. CAD
8. Emphysema
9. COPD
10. Respiratory infections

97

What is the number 1 cancer killer of men and women?

Lung cancer

98

What % of lung cancers is tobacco responsible for?

90%

99

Where does lung cancer rate in terms of cancer incidence in men and women?

#2

100

What are two ways to reduce your cigarette cancer risk?

1. Delay onset of smoking habits
2. Quitting

101

Is nicotine carcinogenic?

No, just a physical addiction

102

What does nicotine do?

Binds to receptors in brain causing release of ACh that increases HR and BP, and contractility and output

103

How are the inhaled agents of cigarette smoke harmful? (3)

1. Act on mucus membranes
2. Swallowed in saliva
3. Absorbed in blood stream to act on distant organs

104

How many components of tobacco are carcinogens?

60

105

Tobacco smoke increases risk of atherosclerosis how?

1. In addition to HT and hypercholesterolemia
2. Increases platelet adhesion and aggregation --> Vascular thromboses --> MI's and CVA's
3. Increase hypoxia --> increase arrhthmias and MI's

106

Effect of tobacco on respiratory? 2

1. Allows for RT infections by destroying cilia
2. Irritation of respiratory epithelium leading to COPD

107

Effect of tobacco on GI?

Peptic ulcer disease

108

Effects of tobacco on fetus?

1. Fetal hypoxia
2. Low birth weight
3. premature
4. increased spontaneous abortion
5. Complications at delivery mainly with placenta

109

Effect of smoking on kids? (3)

1. Infections
2. Asthma
3. SIDS

110

Differences between tobacco chewing and smoking? 4

1. Lungs spared
2. Oral cavity irritation
3. Increased caries, gingivitis, loss of feeth
4. stains tooth enamel

111

What are the numbers used to compare wine, beer, and liquor alcohol contents?

5 ounces of 24 proof wine
12 ounces of 10 proof beer
1.5 ounces of 80 proof liquor

112

Can one die from acute alcohol intake?

Yes

113

How is ethanol absorbed in GI?

Unaltered.

114

Oxidation of ethanol in metabolism produces what?

Toxic agents like acetaldehyde

115

How is ethanol oxidized to acetaldehyde? 3

1. In peroxisome by catalase
2. In cytosol by ADH
3. In microsomes by CYP2E1

116

How is acealdehyde converted to acetic acid?

ALDH in mitochondria

117

What is the genetic polymorphism in alcohol dehydrogenase?

50% of Asians have increased activity due to point mutation so that they convert more than normal ethanol to acealdehyde leading to flushing, nausea, and tachycardia

118

Who has higher levels of gastric alcohol dehydrogenase activity?
What does this mean?

Men

Women develop higher blood alcohol levels than men after same amount of ethanol

119

Acute ethanol toxicity includes? (4)

1. CNS depressant
2. Ulceration
3. Steatosis
4. Acetaldehyde effects --> Esophageal and oral cancers

120

Chronic ethanol toxicity includes?

1. Liver (steatosis, hepatitis, cirrhosis, liver carcinoma)
2. Nervous system: Wernicke-Korsakoff, PN's
3. GI tract: Ulcers, esophageal varices, malnutrition
4. Pancreas: Pancreatitis
5. Cardiac: cardiomyopathy, HT
6. Cancers: Oral, esophageal, liver
7. Pregnancy/Fetus: FAS

121

What is most common cause of preventable congenital retardation in US?
Rate of it?

FAS (1-5 per 1000 births)

122

Ethylene glycol is metabolized by what?
To produce what?

Alcohol dehydrogenase

Glycolic acid and oxalate

123

Glycolic acid is responsible for what? 92)

1. CNS probs
2. Anion gap acidosis

124

Oxalate does what?

Binds calcium to form calcium oxalate that deposits in kidneys.

125

Methanol is metabolized by what?
To form what?

Alcohol dehydrogenase

Formaldehyde and Formic acid

126

Methanol metabolites cause what? (4)

1. Ocular toxicity (blurred vision and blindness)
2. Vomiting
3. Dizziness
4. Elevated anion gap acidosis

127

What do you give to patients with ethylene glycol and methanol overdose? 2

Ethanol or fomepizole to compete for ADH enzyme spots.
Dialysis

128

Elevated anion gap acidosis is do to what? 9

MUDPLIERS
Methanol
Uremia
Diabetic ketoacidosis
Paraldehyde/Phenformin
Isopropyl alcohol/Isoniazid
Lactic acidosis
Ethylene glycol/Ethanol
Rhabdomyolysis
Salicylates

129

How many women use hormonal contraception?
What % of reproductive women use reversible methods?

greater than 100 million

64%

130

What population uses oral birth control pills the most?

Teenagers and Twentys
Never married
College degree

131

Adverse effects of OBC's include?

1. Thromboembolism
2. CV disease
3. Liver tumors

132

OBC's thromboembolism increases DVT risk how much?
What factors increase risk? (5)

3 fold

Factor V mutation
Prothrombin mutation
Older than 35
Smoking
Combined estrogen/progestin OBC's

133

Increased thrombotic risk in OBC's seems due to what?

Acute phase response that increases CRP and coagulation factors (7, 9, 10, 12, 13) and a reduction in anticoagulants (protein S and anti-thrombin III)

134

Explain OBC and CV risk? 2

Being older than 35
Smoker of all ages

135

What type of liver tumors with OBC's?

Benign hepatic adenoma

136

HRT has what risks? 3

1. Endometrial hyperplasia/carcinoma
2. Increased breast carcinoma risk
3. Venous thrombosis and PE (Especially first 2 years of use and if you have other risk factors)

137

Anabolic steroids can have what effects? 7

1. Stunted growth
2. Acne, gynecomastia, and testicular atrophy in males
3. Acne, hirsutism, and menstrual changes in females
4. Rage
5. CAD
6. Hepatic cholestasis
7. Increased prostate carcinoma

138

What is the most commonly used analgesic in the US?

Acetaminophen

139

What percentage of acute liver failure disease is acetaminophen caused?

Half

140

At therapeutic doses what happens in metabolism of acetaminophen?

1. 95% phase II detox in liver and excreted in urine
2. 5% cytochromes convert it to NAPQI which is a reactive metabolite that will harm the liver.

141

What is the therapeutic window?

The window where the therapeutic dose doesn't become toxic

142

Acetaminophen has a small or large therapeutic window?

Large

143

Overdoses of acetaminophen cause what?

GI problems and liver problems

144

What type of therapy is used to reverse acetaminophen toxicity?

Mucomyst (acetylcysteine)

145

What location in the liver has the lowest O2 concentration?

Around central vein

146

Where does acetaminophen cause damage in the liver?

Around central vein

147

Aspirin has what three effects?

1. Irreversibly inhibits COX-1
2. Modifies activity of COX-2
3. Blocks production of thromboxane A2

148

Acute overdose consequences of aspirin are morphologic or metabolic?

Metabolic

149

What happens in an acute aspirin overdose?

1. Respiratory alkalosis
2. Metabolic acidosis
3. Fatal

150

Acidosis in aspirin overdose allows what?

Formation of non-ionized salicylates which go to brain and cause nausea/coma

151

Chronic toxicity of aspirin (salicylism) involves what dose?

3+ grams daily for long periods

152

Symptoms of aspirin chronic toxcitiy?

1. Headaches and tinnitis
2. GI problems
3. Coma
4. Abnormal bleeding.
5. Neuropathy

153

Aspirin and tylenol together is hard on what?

Renal papillae

154

Crystallization of pure cocaine yields what?

Crack cocaine

155

What does cocaine produce?

Euphoria and stimulation

156

Does cocaine have physical dependence?

No, but severe psychological

157

Cocaine blocks reuptake of what? (3)

1. Dopamine
2. Serotonin
3. Catecholamines

158

Cocaine also prolongs what?
And blocks what other reuptake?

Dopaminergic effects in brain pleasure areas

Epinephrine and norepinephrine

159

Clinical clues for possible cocaine abuse?

1. tachycardia/HT
2. CAD
3. Nasal septum problem
4. needle tracts
5. Seizures

160

What is heroin?

Opioid narcotic from opium or synthesized from morphine

161

What is used in treatment of heroine addiction?
Has what problem?

Methadone
Killing people in overdose

162

IV heroin and other opiates cause what?

1. CNS depression: hypoventilation (respiratory acidosis), GI issues, seizures
2. Pulmonary injury: Edema, emboli, granulomas
3. Infections: Skin, heart valves, liver, and lungs

163

What are two main infections due to heroin?

1. Staph aureus on tricuspid valve
2. Viral hepatitis

164

Evidence of heroin addiction? (4)

1. Narcotic abstinence syndrome
2. Infections
3. Renal disease: Focal segmental glomerulosclerosis
4. Cutaneous scars, hyperpigmentation of skin over veins and thrombosed veins.

165

Two types of amphetamines?

Methamphetamines
MDMA

166

Methamphetamine acts how?

Releases dopamine --> Inhibits presynaptic neurotransmission at corticostriatal synapses, slowing glutamate release --> Euphoria with a crash

167

How does MDMA/ecstasy work?

Euphoria and hallucinations due to altered serotonin levels in CNS

168

Marijuana is from what?

Cannabis sativa plant with high levels of THC

169

Marijuana has what effects?

1. Distorts sensory and motor
2. Euphoria, paranoia, bad judgment
3. Increased appetite and dry mouth
4. Irritant and carcinogen

170

Cycad flour contains what?

Toxin cycasin

171

How do you avoid the toxins in cycad flour?

Cut seeds and soak them to get the toxin out.

172

Cycasin poison has what effect?

Degenerative neurologic disorder

173

Aflatoxins are natural toxins produced by what?

Aspergillus?

174

Where is aspergillus found?

In stored grains

175

Aflatoxin effect on humans?

1. Toxic to liver
2. Carcinogenic to liver

176

Unintentional injuries/trauma rank where in deaths of adolescents and adults under 44 y/old?

First

177

What percentage of unintentional injuries involve ethanol?

40%

178

Motor vehicle accidents caused by what?

1. Impact of vehicle on person
2. Ejection from vehicle
3. Trapped in vehicle
4. Alcohol use

179

What is an abrasion?

superficial epidermis is torn off by friction or
force

180

Is there scarring in abrasion healing?

No, but risk of infection

181

What is a laceration?

irregular tear in the skin produced by tissue
stretching due to blunt force

182

Lacerations are typically seen how? 2

1. bridging strands of fibrous tissue or
blood vessels across the wound
2. immediate margins are frequently hemorrhagic
and traumatized

183

Incisions are usually made by what?

Sharp cutting object

184

Describe margins and bridging in incisions?

Margins = clean
No bridging

185

What is a stab wound?

depth of wound greater than length of
wound

186

What is puncture wound?

deep penetrating wounds made by a
long thing object such as a nail or ice pick

187

What is penetration wound?

open wound that enters and
exists the body

188

What is a gun shot wound?

caused by bullets or pellets fired from a gun, can be penetrating if the bullet or pellets exit the body

189

What is a contusion?

blunt force that damages small vessels and causes extravasation of blood into tissues

190

What is a superficial burn?

(1st degree): Confined to
epidermis

191

What is a partial thickness burn?

(2nd degree): Injury to the
dermis (at least the deeper portions of the dermal
appendages are spared to regenerate epithelium)

192

What is a full thickness burn?

Extends to subcutaneous
tissue (3rd degree) and may involve muscle (4th
degree)

193

What is destroyed in full thickness?

the epidermis and dermis
and anesthesia due to nerve ending destruction

194

What will cause a burn to be fatal?

Any burn exceeding 50% of total BSA

195

What happens if burn is above 20% BSA?

Fluid shifts to interstitial compartments --> Hypovolemic shock

196

What causes the hypovolemic shock in a burn? 2

1. Increase in interstitial osmotic pressure
2. Neurogenic and mediator induced vascular permeability

197

Injury to airways and lungs in thermal injury may result from what? 2

1. Direct effect of heat
2. Inhalation of smoke

198

What is teh most common seconday infection in thermal injury?
What other two?

Pseudomonas aeruginosa

Candida and s. aureus

199

What causes heat cramps?
What is the hallmark
What is the mechanism?

Loss of electrolytes through sweating

Cramping of voluntary muscles during exercise is
the hallmark

Heat dissipating mechanisms able to maintain
normal core temp

200

What is the onset of heat exhaustion?
Why does it occur?

Sudden collapse

failure of the cardiovascular system to
compensate for hypovolemia, secondary to water
depletion

201

What is heat stroke associated with? (2)

High ambient temperature
High humidity

202

What fails in heat stroke?

Thermoregulatory mechanisms fail, sweating
ceases, and core body temp rises – multi-organ
dysfunction - death

203

What is the sign of heat stroke?

Rectal temp above 106 F

204

What is the mechanism of heat stroke?

Mechanism is peripheral vasodilation with marked
pooling of blood and a decreased effective
circulating volume

» Necrosis of skeletal and cardiac muscle -
rhabdomyolysis

205

Lowering of body temperature in systemic hypothermia is exacerbated by what? 3

1. high humidity
2. cold wet clothing
3. alcohol

206

When body gets to 90 degrees F, what happens? (3)

1. loss of consciousness
2. bradycardia
3. atrial fib

207

What do hypothermic patients do that seems strange?

Want to take clothes off despite freezing

208

What is frostnip?

cooling, usually of apical structures such as
nose, cheeks and ears, from cold air exposure

209

What is chilblain?

exposure to damp, non-freezing
temperatures that causes a vasculitis with red, raised
lesions

210

What is immersion foot?

prolonged exposure
to wet, cool conditions

211

What is frostbite?

Freezing of tissue

212

Which is the most severe form of peripheral cold injuries?

Frostbite can lead to ischemia, gangrene and amputation

213

Direct effects of hypothermia are mediated by what? 2

1. Physical disruption of organelles within the cells
2. High salt concentrations incident to the crystallization of the intra and extracellular water

214

Indirect effects of hypothermia result from what?
What do they depend on? 2

Circulatory changes
1. Rate of temp drop
2. Duration of temp drop

215

Slow chilling induces what? (2)
Leading to what?

1. vasoconstriction
2. increased permeability

edema

216

Rapid chilling induces what? (2)
What happens upon temperature rising?

1. Vasoconstriction
2. Ischemic injury

Increased permeability with exudation

217

Electrical injury in the house can be serious when?

If there is low resistance like wet skin, can cause serious injury like ventricular fib

218

Current from high voltage sources are more likely to produce what? (2)

1. Paralysis of medullary centers
2. Extensive burns

219

What are two most important variables in electrical injury?

1. Resistance of tissue
2. Intensity of current

220

Tissue resistance to flow varies how with water content?

Inversely.
Dry skin has greater resistance than wet

221

Thermal effects of electrical injury depends on what?

intensity of current

222

What is radiation?

energy that travels in the form of
waves or high-speed particles

223

Two types of radiation?

Nonionizing
Ionizing

224

Non-ionizing radiation is characterized by what? 3

longer wavelengths, lower
frequencies and lower energy

225

Ionizing radiaiton can cause what?

Tissue heating

226

typical sources of non-ionizing radiation? 2

sunlight
UV

227

Ionizing radiation is characterized by what?

Shorter wavelengths
Higher frequency
Higher energy

228

Ionizing radiation will disrupt what?

Metabolism.

229

Examples of ionizing radiation? (5)

1. X rays
2. gamma rays
3. high energy neutrons
4. Alpha particles
5. beta particles

230

Alpha particles induce what type of damage?
What do they do poorly?

Heavy damage in a certain area

Penetrate poorly due to size

231

3 ways to measure ionizing radiation units?

1. Amount emitted by source
2. Amount absorbed
3. Effect of radiation

232

What is a Curie?
It is an expression of what?

Amount of disintegration per second of a radionuclide.

Amount of radiation emitted

233

What is a Gray?

The energy absorbed by the target tissue per unit mass

234

What is a Sievert?

Unit of doses that depends on biologic effects of radiation

235

What areas of the body are most affected by ionizing radiation? 2
Why?

Bone marrow and GI

Rapidly dividing

236

What are the main determinants of biological effect of ionizing radiation?

1. Rate of delivery
2. Field size
3. Cell proliferation
4. Oxygen effects and hypoxia
5. Vascular damage

237

explain how rate of delivery impacts ionizing radiation effect?

Divided doses allow cells to repair some damage during exposures.

238

Which recover faster to radiation, normal cells or tumor cells?

Normal cells

239

Explain how size of field can have effect on ionizing radiation damage?

High doses at small shielded fields = okay
Smaller doses to larger fields = bad

240

Explain how proliferation can have effect on ionizing radiation damage?

Damages DNA so rapidly dividing cells are vulnerable: Gonads, BM, lymph, mucosa of GI

241

Cells in what cell cycle stages are most susceptible to ionizing radiation damage?

G2 and M

242

What is the most important mechanism of radiation damage?

Production of ROS

243

Which is more sensitive to radiation injury, well vascularized or poorly vascularized tissues?

Well Vascularized (more O2)

244

Effect of radiation on BV's?

Sclerosis which impairs function

245

BV change to radiation?

Subintimal fibrosis with narrowing of lumen

246

Skin changes to radiation?

1. Atrophy of epidermis
2. Hyperkeratosis and hyper/hypopigmentation

247

How long can squamous and basal cell carcinomas occur after radiation exposure?

20 years

248

Heart changes due to radiation?

Fibrosis

249

Lung changes due to radiation?

Fibrosis

250

Kidney changes due to radiation? 2

1. Fibrosis
2. Hyalinizatin of glomeruli

251

GI, breast changes due to radiation?

Fibrosis

252

Ovary and testis changes due to radiation?

Suppression of meiosis --> infertility