Hertz: Environmental

Question 1

how to measure environmental effects on global disease burden

Answer 1

DALY (disability-adjusted life year)

Question 2

slim man’s disease

Answer 2

losing weight
can’t breathe well
diarrhea

= HIV/ AIDS

Question 3

Health effects of climate change

Answer 3

Cardiovascular, cerebrovascular, and respiratory diseases, all of which will be worsened by heat waves and air pollution

Gastroenteritis, cholera, and other foodborne and waterborne infectious diseases, caused by contamination as a consequence of floods and disruption of clean water supplies and sewage treatment, after heavy rains and other environmental disasters

Vector-borne infectious diseases, such as malaria and dengue fever, due to changes in vector number and geographic distribution related to increased temperatures, crop failures, and more extreme weather variation (e.g., more frequent and severe El Niño events)

Malnutrition, caused by changes in local climate that disrupt crop production. Such changes are anticipated to be most severe in tropical locations, in which average temperatures may already be near or above crop tolerance levels; it is estimated that by 2080, agricultural productivity may decline by 10% to 25% in some developing countries as a consequence of climate change.

Question 4

poison dosage

Answer 4

when 50% of the population dies, it’s the LD50 toxicity

Question 5

The P-450 system

Answer 5

catalyzes reactions that either detoxify xenobiotics or, less commonly, convert xenobiotics into active compounds that cause cellular injury

Question 6

particulate matter

Answer 6

(known as “soot) is a particularly important cause of morbidity and mortality related to pulmonary inflammation and secondary cardiovascular effects.

Question 7

Wood smoke

Answer 7

containing various oxides of nitrogen and carbon particulates, is an irritant that may predispose to lung infections and may contain polycyclic hydrocarbons, important carcinogens.

can contribute to indoor air pollution

Question 8

Bioaerosols

Answer 8

range from microbiologic agents capable of causing infectious diseases such as Legionnaires disease, viral pneumonia, and the common cold, to less threatening but nonetheless distressing allergens derived from pet dander, dust mites, and fungi and molds responsible for rhinitis, eye irritation, and asthma.

Question 9

Radon

Answer 9

a radioactive gas derived from uranium widely present in soil and in homes, can cause lung cancer in uranium miners. However, it does not seem that low-level chronic exposures in the home increase lung cancer risk, at least for nonsmokers

Question 10

Exposure to formaldehyde

Answer 10

, used in the manufacture of building materials (e.g., cabinetry, furniture, adhesives) may be a health problem in refugees from environ­mental disasters living in poorly ventilated trailers. At concentrations of 0.1 ppm or higher, it causes breathing difficulties and a burning sensation in the eyes and throat, and can trigger asthma attacks. Formaldehyde is classified as a carcinogen for humans and animals.

Question 11

sick building syndrome

Answer 11

remains an elusive problem; it may be a consequence of exposure to one or more indoor pollutants, possibly due to poor ventilation

Question 12

big 4 heavy metals

Answer 12

lead
mercury
Arsenic
Cadmium

Question 13

Lead

Answer 13

competes with calcium

interferes with the normal remodeling of cartilage and primary bone trabeculae in the epiphyses in children. This causes increased bone density detected as radiodense “lead lines”; another type of lead line appears in the gums as a result of hyperpigmentation.

Question 14

lead poisoning in kids vs adults

Answer 14

kids present with… encephalopathy, then motor neuropathies

adults present with … neuropathies

will show with basophilic stippling on peripheral blood smear

Question 15

arsenic looks like

Answer 15

brown spots on the hands

Question 16

chronic arsenic poisoning

Answer 16

Neurologic effects usually occur 2 to 8 weeks after exposure and consist of a sensorimotor neuropathy that causes paresthesias, numbness, and pain.

causes skin changes: hyperpigmentation and hyperkeratosis

The most serious consequence of chronic exposure is the increased risk for the development of cancers, particularly of the lungs, bladder and skin. Arsenic-induced skin tumors differ from those induced by sunlight; they are often multiple and usually appear on the palms and soles. The mechanisms of arsenic carcinogenesis in skin and lung have not been elucidated but may involve defects in nucleotide excision repair mechanisms that protect against DNA damage.

Evidence that chronic exposure to arsenic in drinking water can cause non-malignant respiratory disease

Question 17

Cadmium

Answer 17

increased ROS and –> obstructive lung disease and kidney damage

Question 18

acute alcoholism

Answer 18

exerts its effects mainly on the CNS, but it may induce hepatic and gastric changes that are reversible if alcohol consumption is discontinued.

Question 19

hepatic change w/ alcohol

Answer 19

Even with moderate intake of alcohol, multiple fat droplets accumulate in the cytoplasm of hepatocytes (fatty change or hepatic steatosis). The gastric changes are acute gastritis and ulceration.

Question 20

alcohol and the CNS

Answer 20

In the CNS, alcohol is a depressant, first affecting subcortical structures (probably the high brain stem reticular formation) that modulate cerebral cortical activity. Consequently, there is stimulation and disordered cortical, motor, and intellectual behavior. At progressively higher blood levels, cortical neurons and then lower medullary centers are depressed, including those that regulate respiration. Respiratory arrest may follow.

Question 21

chronic alcoholism

Answer 21

affects not only the liver and stomach, but virtually all other organs and tissues as well. Chronic alcoholics suffer significant morbidity and have a shortened life span, related principally to damage to the liver, gastrointestinal tract, CNS, cardiovascular system, and pancreas.

Question 22

u world stuff with alcohol

Answer 22

cirrhosis, hemorrhagic pancreatitis, squamous cell carcinoma in the mouth, esophageal varices, cardio myopathy…

Question 23

menopausal hormone therapy

Answer 23

Combination estrogen-progestin increases the risk of breast cancer after a median time of 5 to 6 years. In contrast, estrogen alone in women with hysterectomy is associated with a borderline reduction in risk of breast cancer.

MHT may have a protective effect on the development of atherosclerosis and coronary disease in women younger than age 60 years, but there is no protection in women who started MHT at an older age.

MHT increases the risk of stroke and venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism. The increase in VTE is more pronounced during the first 2 years of treatment and in women who have other risk factors such as immobilization and hypercoagulable states caused by prothrombin or factor V Leiden mutations.

Question 24

Oral Contraceptives (OCs)

Answer 24

Breast carcinoma: The prevailing opinion is that OCs do not increase breast cancer risk.

Endometrial cancer and ovarian cancers: OCs have a protective effect against these tumors.

Cervical cancer: OCs may increase risk of cervical carcinomas in women infected with human papillomavirus, although it is unclear whether the increased risk merely reflects greater sexual activity in women on OCs.

Question 25

oral contraceptives and thromboembolism

Answer 25

Most studies indicate that OCs, including the newer low-dose (less than 50 µg of estrogen) preparations, are associated with a threefold to sixfold increased risk of venous thrombosis and pulmonary thromboembolism due to a hypercoagulable state induced by elevated hepatic synthesis of coagulation factors. This risk may be even higher with newer “third-generation” OCs that contain synthetic progestins, particularly in women who are carriers of the factor V Leiden mutation. To put this complication into context, however, the risk of thromboembolism associated with OC use is two to six times lower than the risk of thromboembolism associated with pregnancy.

Question 26

oral contraceptives and cardiovascular disease

Answer 26

It seems that OCs do not increase the risk of coronary artery disease in women younger than 30 years or in older women who are nonsmokers, but the risk does approximately double in women older than 35 years who smoke

Question 27

oral contraceptives and hepatic adenoma

Answer 27

There is a well-defined association between the use of OCs and this rare benign hepatic tumor, especially in older women who have used OCs for prolonged periods. The tumor appears as a large, solitary, and well-encapsulated mass.

Question 28

overdose of acetaminophen

Answer 28

–> hepatocyt necrosis

liver failure

Question 29

overdose of aspirin –>

Answer 29

tinnitis

also initially respiratory acidosis, then alkalosis

Question 30

cocaine

Answer 30

Cardiovascular effects.
Tachycardia, hypertension, and peripheral vasoconstriction.
Myocardial ischemia by causing coronary artery vasoconstriction
Lethal arrhythmias

CNS. The most common acute effects on the CNS are hyperpy­rexia (thought to be caused by aberrations of the dopaminergic pathways that control body temperature) and seizures.

Effects on pregnancy. In pregnant women, cocaine may cause acute decreases in blood flow to the placenta, resulting in fetal hypoxia and spontaneous abortion. Neurologic development may be impaired in the fetus of pregnant women who are chronic drug users.

Question 31

cocaine and neurotransmission

Answer 31

inhibits reuptake of the neurotransmitters dopamine and norepinephrine –>

CNS: euphoria, paranoia, hyperthermia,

Sympathetic neuron: hypertension, cardiac arrhythmia, myocardial infarct, cerebral hemorrhage and infarct

Question 32

Opiates

Answer 32

talc in the heroin –> granuloma in the lung

lymphangitis from needle tracks

infections

Question 33

heat exhaustion

Answer 33

hot, sweaty, pupils dilated

normal or subnormal temp

Question 34

heat stroke

Answer 34

dry hot skin, pupils constricted, very high body temperature

Question 35

Hypothermia: direct and indirect effects

Answer 35

Direct effects are probably mediated by physical disruptions within cells by high salt concentrations caused by the crystallization of intra- and extracellular water.
Indirect effects result from circulatory changes, which vary depending on the rate and duration of the temperature drop. Slow chilling may induce vasoconstriction and increase vascular permeability, leading to edema and hypoxia. Such changes are typical of “trench foot.” This condition developed in soldiers who spent long periods of time in waterlogged trenches during the First World War (1914-1918), frequently causing gangrene that necessitated amputation. With sudden, persistent chilling, the vasoconstriction and increased viscosity of the blood in the local area may cause ischemic injury and degenerative changes in peripheral nerves. In this situation, vascular injury and edema become evident only after the temperature begins to return to normal. However, during the period of ischemia, hypoxic changes and infarction of the affected tissues (e.g., gangrene of toes or feet) may develop.

Question 36

radiation –>

Answer 36

may injur cells directly or indirectly by generating free radicals from water or molecular oxygen

damages DNA; therefore, rapidly dividing cells such as germ cells, and those in the bone marrow and gastrointestinal tract are very sensitive to radiation injury

DNA damage that is not adequately repaired may result in mutations that predispose affected cells to neoplastic transformation

Ionizing radiation may cause vascular damage and sclerosis, resulting in ischemic necrosis of parenchymal cells and their replacement by fibrous tissue

Question 37

Dietary insufficiency: 2 concepts

Answer 37

protein loss or calorie loss

Question 38

marasmus means

Answer 38

no muscles

Question 39

kwashiorkor

Answer 39

edematous. calories but no protein (albumin)

Question 40

in cachexia

Answer 40

TNF triggers autophagy

Question 41

vitamin A

Answer 41

from meat and veggies
made and stored in liver, cells of Ito
RETINOL ester important for eyes, lungs, kidneys (squamous or cuboidal epithelium)

Question 42

vitamin D

Answer 42

sun
need liver to convert
need kidney to convert again

Question 43

vitamin C deficiency

Answer 43

–> impaired collagen formation

need for wound healing
deficiency can cause bleeding of gums

Question 44

obesity

Answer 44

Excess adiposity (obesity) and excess body weight are associated with increased incidence of several of the most important diseases of humans, including type 2 diabetes, dyslipidemias, cardiovascular disease, hypertension, and cancer

seems to cause metabolic syndrome

insulin resistance–> hyperinsulinemia–> IGF–> cancer

increases steroid hormones as well

also chronic inflammation (–> cancer)