Environmental And Nutritional Disease Flashcards
Indoor,, outdoor and occupation setting in which human beings live and work
Environmental
Conditions caused by exposure to chemical or physical agents in th ambient, workplace and personal environment
Environmental disease
Studies the distribution effects and MOA of toxic agents
Toxicology
Exogenous chemicals in the environment that may be absorbed into the body
Xenobiotics
Responsible for the catalyzation of xenobiotics that either detoxify or convert xenobiotics into active compound
P-450 enzyme
Phase 1 reaction os xenobiotics
Hydrolysis
Reduction
Oxidation
Phase 2 reactions of xenobiotics
Glucorinidation
Sulfation
Methylation
Conjugation
Significant cause of morbidity and mortality worldwide
Air pollution
Sulfur dioxide, CO, ozone, nitrogen dioxide, lead and particulate matter
Smog
Produced by the interaction of UV rad and oxygen in the stratosphere
Ozone
What destroys ozone layer
Chlorofluorocarbon
Protects life by absorbing UV rad emitted by the sun
Ozone
Formed by reaction of nitrogen oxides and volatile organic compounds
Ozone
Produces free radicals which injures epithelial cells of the respiratory tract
Ozone
Emitted by burning coal, oil-fired and diesel exhaust
Particulate matter - soot
Systemic asphyxiant that is an important cause of accidental and suicidal death
Carbon monoxide
Produced during any process that results in the incomplete oxidation of hydrocarbons
Carbon monoxide
Chronic carbon monoxide poisoning in individuals usually occurs in workplaces such as?
Tunnels
Underground garages
Highway toll booths
Signs of carbon monoxide poisining
Fatigue
Dizziness
Tightness in chest
Headache
Nausea
Ischemic changes in ___ and ___ are seen in patients who are chronically exposed to CO
Basal ganglia and lenticular nuclei
Most common indoor air pollution
Tobacco smoke
No.1 cause of lung cancer in non-smokers
Radon
Indoor air pollution
Formaldehyde —- ???
Carcinogen
Metals as environmental pollutants
Heavy metals, lead, mercury, cadmium and arsenic
Binds to sulfhydryl groups in proteins and interferes with calcium metabolism
Lead Pb
Absorbed lead is taken into developing teeth and bone where it competes with ___ and binds ___
Calcium
Phosphates
Is lead susceptible to brain damage?
Yes, due to more permeable BBB
Results in microcytosis and anemia
Lead
interferes with delta-aminolevulinic acid dehydratase and ferrochelatase
Lead
Binds to sulfhydryl groups in proteins with high affinity - leads to damage in the CNS and kidneys
Mercury
Main source of exposure to mercury
Contaminated fish
Mercury vapors
Dental amalgams
Three forms of mercury
Elemental mercury
Inorganic mercury
Organic mercury
inorganic mercury is converted to ___ by bacteria
Methyl mercury
Mercury toxicity:
____ - cerebral palsy, deafness, blindness, intellectual disability, major CNS defects in children exposed in utero
Minamata disease
Interferes with mitochondrial oxidative phosphorylation
Arsenic
Most toxic form of arsenic
Trivaleny compounds arsenic trioxide
Sodium arsenite
Arsenic trichloride
Neurologic effects of arsenic
Sensorimotor neuropathies
Cardiovascular effects of arsenic
Prolonged Q-c interval with ventricular arrhythmias
Skin changes in arsenic
Hyperpigmentation and hyperkeratosis
Risk in malignancies in arsenic
Lung, bladder and skin
Preferentially toxic to the kidneys and lungs
Cadmium
The most important source of cadmium exposure in the general population
Food
Cadmium is acquired from?
Mining, electroplating and production of batteries
Cadmium causes _____ by necrosis of alveolar epitherlial cells
Obstructive lung disease
Osteoporosis and osteomalacia associated with renal disease - “___” in cadmium
Itai-itai
Agent
Chloroform and carbon tetrachloride
Disease?
CNS effects, liver and kidney toxicity
Agent
Benzene and 1,3 butadiene
Disease?
Leukemias
Agent
Polycyclic hydrocarbons
Disease
Lung and bladder cancer
Agent
Organochlorines
Disease
Neurologic toxicity, endocrine disruptor
Agent:
Dioxin and PCB
Disease??
Folliculitis and acneiform dermatosis
Agent: vinyl chloride
Disease??
Hepatic angiosarcoma
Agent: bisphenol A
Disease??
Endocrine disruptor
Agent: mineral dusts
Disease??
Pneumoconioses
What is the most readily preventable cause of death in humans
Smoking
Chewing tobacco is associated with __ disease
Oral cancer
Average number of cigarette packs smoked each day multiplied by the number of years of smoking
Pack-years
Stimulates release of catecholamines from sympathetic neurons
Nicotine
The effect of tobacco that has direct irritant effect on the _____ mucosa
Tracheobronchial mucosa
Tobacco is strongly linked to development of ??
Atherosclerosis, MI and stroke
Chronic relapsing brain disease characterized by an impaired ability to stop of control alcohol use despite adverse, social, occupational, or health consequences
Alcohol use disorder (AUD)
Why breath test can determine alcohol consumption
Because amount exhaled is proportional to the blood level
___ is absorbed unaltered in the GI tract and then distributes throughout the body in direct proportion to the blood level
Ethanol
When taking alcohol, drowsiness occurs at ___ mg/dl
200 mg/dl
Individuals with low levels of _____ metabolize alcohol slowly
Acetaldehyde (ALDH)
Acute effects of alcohol
Hepatic steatosis
Acute gastritis and ulceration
CNS depression
Alcohol oxidation by ADH causes reduction of ___ to ____ Decrease ___ results in decrease FA oxidation in the ___ which results in _____ in the liver
NAD to NADH
NAD
Liver
Accumulation of fat
Metabolism of ethanol in the liver by CYP2E1 produces ___ ?
ROS
alcohol promotes release of ___ from intestinal flora
Endotoxin
Chronic effects of alcohol
Alcoholic hepatitis and cirrhosis
Gastric bleeding and ulcer
Thiamine deficiency
Dilated congestive cardiomyopathy
Hypertension
Acute and chronic pancreatitis
Fetal alcohol syndrome
Oral cavity malignancies
Malnutrition
Vitamin K antagonist
Warfarin
Direct inhibitor of thrombin
Dabigatran
Used to counteract menopausal symptoms
Menopausal hormone therapy
Composed of either synthetic estradiol + variable amount of progestin or progestin only
Oral contraceptives
Acts by inhibiting ovulation or preventing implantation
Oral contraceptives
Have a protective effects against endometrial and ovarian cancers
Oral contraceptives
A contraceptIncrease risk of hepatic adenoma
Oral contraceptive
When taken in large dose, NAPQI accumulates which leads to hepatocellular injury
Acetaminophen
Covalently binds to hepatic proteins and deletes GSH
Acetaminophen
Extracted from the leaves of coca plant
Cocaine
Produces intense euphoria and neurologic stimulation
Addictive
Cocaine at the nerve endings blocks the reuptake of?
Epinephrine and norepinephrine
Cocaine in neurotransmission in the CNS blocks reuptake of?
Dopamine
Derived from poppy plant
Heroin
Acts by releasing dopamine in the brain which inhibits presynaptic neurotransmission at corticostriatal synapses, slowing glutamate release
Methamphetamine
Derived from leaves of cannabis sativa
Marijuana
Psychoactive substance o marijuana is called?
Tetrahydrocannabinol
Potential use to treat nausea secondary to cancer chemotheraphy
Marijuana
Mechanical trauma
Abrasion
Contusion
Laceration
Incision
Puncture wound
4 injuries by physical agents
Mechanical trauma
Thermal injury
Electrical injury
Radiation injury
Damage by direct injury to tissue and by inhalation injury
Thermal burns
Thermal burns that is confined to epidermis
Superficial burns
thermal burn that dermis is involved
Partial thickness burns
thermal burn that extends to the subcutaneous tissue
Fulll-thcknes burns
Heat cramps
Hyperthermia
Results from loss of electrolytes via sweating
Hyperthermia - heatcramps
Hallmark of heat cramps
Cramping of muscles during exercise
Most common hyperthermic syndrome
Hyperthermia - heat exhaustion
Results from failure of the CVD system to compensate from hypovolemia caused by dehydration
Hyperthermia - heat exhaustion
Associated with high ambient temperature, high humidity and exertion
Hyperthermia - heat stroke
Failure of thermoregulatory mechanism which results in increased body temperature
Hyperthermia - heat stroke
Receptors that regulates calcium release from sarcoplasm in heat stroke
RYR1
Results in mutations in genes that encode RYR1
Hyperthermia - malignant hyperthermia
Results from prolonged exposure to low ambient temperature
Hypothermia
Direct injury is due to cell injury caused by crystallization of intracellular and extracellular water
Hypothermia
Results in burns, and disruption of nerve impulse conduction
Electrial injury
High voltage are more likely to produce paralysis in medullary centers
Electrical injury
Energy that travels in the form of waves or high-speed particles
Radiation
____ radiation has sufficient energy to remove tightly bound electrons
Ionizing radiation
____ radiation can move atoms in a molecule but is not sufficient to displace electrons from atoms
Nonionizing radiation
Radiation unit:
Expression of amount of radiation emitted by a source
Curie (Ci)
radiation unit:
Unit that expresses the energy absorbed by the target tissue per mass unit
Gray (Gy)
Radiation unit:
Unit of equivalent dose that depends on the biologic rather the physical effects of radiation
Sievert (Sv)
Main determinants of biologic effect of ionizing radiation
Rate of delivery
Field size
Cell proliferation
Oxygen effects and hypoxia
Vascular damage
normal cells repair radiation damage more quickly than neoplasic cells, fractionated doses only damages neoplastic cells in the long term
Rate of delivery
Body can sustain higher radiation dosage when given to a smaller area: smaller doses in larger area may be lethal
Field size
Rapidly dividing cells are more vulnerable to injury than quiescent cells
Cell proliferation
ionizing radiation results in radiolysis of water which produces ROS; hypoxic tissues are more resistant to radiation
Oxygen effects and hypoxia
Endothelial damage by radiation may result in narrowing of blood vessels
Vascular damage
Injury produced by ionizing radiation
DNA damage
Cellular changes
Fibrosis of vessels
A common side effect of radiation
Fibrosis
replacement of dead cells by connective tissue
Fibrosis
leads to scar formation and adhesion
Fibrosis
Double stranded breaks and repaired either via ___ or ____ end joining
Homologous recombination
Non-homologous
DNA repair via ___ often results in mutation - carcinogenesis
NHEJ
One of the components are missing in the diet
Primary malnutrition
Results from malabsorption, impaired utilization, excess loss or increase need for nutrients
Secondary malnutrition
Previously called protein energy malnutrition
Severe acute malnutrition
Severe acute malnutrition can affects the 2 compartments
Somatic and visceral compartment
Develops when the diet is severely lacking in calories
Marasmus
When does a child is considered to have a marasmus?
When weight falls o 60% of normal
Extremities are emaciated due to loss of muscle and subcutaneous fat
Marasmus
Occurs when protein deprivation is relatively greater than the reduction in total calories
Kwashiorkor
Most common form of SAM seen in african children who are exclusively fed on a carbohydrate diet
Kwashiorkor
Weight of children are typically 60 - 80% of normal
Kwashiorkor
Often develops in chronically ill, older and bedridden patients
Malnutrition
Self-induced starvation resulting in marked weight loss
Anorexia nervosa
condition in which the patient binges on food and then induces vomiting
Bulimia
Endocrine effects and symptoms of anorexia
Amenorrhea and hypothyroidism
Maintenance of normal vision, regulation of cell growth and differentiation and regulation of lipid metabolism
Vitamin A
Group of related compounds that include retinol, retinal and retinoic acid
Vitamin A
Conversion of retinol occurs in the ____ ?
Intestine
Maintenance of normal vision - light sensitive pigments
Vitamin A
Cell growth and differentiation - binds to retinoic acid receptors and RXR - maintenance of cell growth and differentiation
Vitamin A
Vitamin A deficiency
Bitot spots
Corneal ulcer
Keratomalacia
What are the fat soluble vitamins
Vitamin A D E K
Maintenance of adequate plasma levels of calcium and phosphorus
Vitamin D
supports metabolic functions, bone mineralization and neuromuscular transmission
Vitamin D
Major source in humans is the endogenous synthesis from 7-dehydrocholesterol
Vitamin D
Reaction requires UV light which results in synthesis of cholecalciferol
Vitamin D
Where does 25-hydroxycholecalciferol is being converted to?
In the liver
Most active form of vitamin D
1,25 dihydroxyvitamin D
Overgrowth of epiphyseal cartilge
Persistence of distorted, irregular masses of cartilage
Inadequate mineralization of osteoid matrix
Rickets
Inadequate mineralization of bone matrix
Weak bones which are prone to fractures
Osteomalacia
Not synthesized endogenously; supply is dependent on diet
Collagen synthesis - hydroxylation of procollagen
Antioxidant function, immune response
Vitamin C (ascorbic acid)
Vitamin C deficiency
Scurvy
defined as accumulation of adipose tisue that s of sufficient magnitude to impair health
Obesity
Obesity, what circuit
= promotes food intake and reduced energy expenditure
Anabolic circuits
obesity, what circuits
=reduces food intake and increases energy expenditure
Catabolic circuits
The three afferent system
Leptin, adiponectin, gut hormone
Secreted by fat cells
Reduces food intake by stimulating POMC/CART and inhibits NPY/AgRP neurons
Abundance of leptin stimulates physical activity, heat production and energy expenditure
Afferent system - leptin
“Fat burning molecules” reduces fatty acid levels
Stimulates FA oxidation in skeletal muscle
Protects against metaboic syndrome in decreasing glucose production, increases insulin sensitivity
Has anti-inflammatory, antiatherogenic, antiproliferative and cardioprotective effects
Afferent system - adiponectin
Increases food intake
Ghrelin
Short term meal initiators and terminators
Ghrelin
PYY and GLP-1
Decreases food intake
PYY and GLP-1
