Saturday, December 8, 2007

APES Tropical Infectious Diseases Research - Shope

Tropical Infectious Diseases - Research




A – Trypanosomiasis (sleeping sickness)
o vector: Tsetse fly

o symptoms
• massive stimulation of immune system
• generalized pain, weakness, cramps
• swelling of neck lymph nodes
• apathy, mental dullness
• tremors, convulsions
• sleepiness, coma
• rapid weight loss

o Sub-Saharan Africa
o 20,000 new cases a year



B – Schistosomiasis
o parasitic disease
o leads to chronic ill health
o Central China & Egypt… other developing countries as well
o documented existence since the time of the Egyptian pharaohs
o indicated by blood in urine or serious complications involving the liver and spleen
o infected by contact with water used in normal daily activities (hygiene, swimming, fishing, irrigation, etc.)
o infected individuals may contaminate their water supply with feces or urine due to lack of information or insufficient attention to hygiene



C – Lassa Fever
o acute viral illness
o West Africa
o zoonotic (rodent)

o transferred through…
• direct contact with rodent’s urine or droppings
• touching objects or eating food contaminated with these materials
• open cuts or sores

o endemic (constantly present)
o mild, no symptoms in 80% of infected people

o symptoms present 1 – 3 weeks later
• varied and non-specific
• fever
• sore throat
• back pain, abdominal pain
• cough
• vomiting, diarrhea
• hearing loss, tremors

o 100,000 – 300,000 new cases per year



D – Filariasis
o caused by parasitic worms transmitted by mosquitoes
o extremely rare in Western countries

o biggest symptom: elephantiasis
• thickening of skin and underlying tissues
• caused when parasites lodge in the lymphatic system
• mainly affects lower extremities
• not known to be fatal, though it can cause a fair amount of pain

o other symptoms
• swelling (lymph nodes, arm, leg, etc.)
• fever, aches, pain
• thickened skin
• warty skin appearance

o endemic in tropical regions of Asia, Africa, Central America, South America
o 120 million people infected



E – River Blindness
o world’s second leading infectious cause of blindness
o caused by a parasitic worm that can live in the body for up to 15 years

o symptoms
• skin: intense itching, swelling, inflammation, loss of elasticity
• blindness
• skin cancer

o West and Central Africa
o about 18 million infected… 300,000 irreversibly blind



F – West Nile Virus
o tropical and temperate regions
o mainly infects birds
o main route to human infection: via mosquito

o symptoms
• nausea, vomiting, loss of appetite, diarrhea
• tiredness, decreased level of consciousness (near-coma), coma
• stupor, disorientation
• fever, headache
• skin rash (trunk of body)
• neck stiffness
• tremors, convulsions
• muscle weakness, paralysis

o symptoms generally last for a few days
o deadly if it enters the brain



G – SARS
o Severe Acute Respiratory Syndrome
o has been one near pandemic in 2002/2003
o originated in China

o symptoms
• initially are flu-like
• high fever (above 100.4F)
• lethargy
• muscle pain
• gastrointestinal symptoms
• cough, sore throat

o caused by virus from same family as the common cold
o much more harmful to animals than humans
o airborne



H – Trichinosis
o parasitic disease
o caused by: eating raw or undercooked pork and wild game infected with larvae
o person-person spread doesn’t occur

o symptoms (usually 10 – 14 days after infection)
• fever
• muscle soreness
• pain and swelling around eyes
• thirst
• profuse sweating, chills
• weakness, tiredness
• chest pain

o partial immunity may develop
o fatal if not treated



I – Prions
o infectious agents composed of only protein
o cause a number of diseases in a variety of animals
o cause neurodegenerative disease
o “holes” in normal tissue structure
o very long incubation period
o once symptoms appear, the disease progresses rapidly… leading to brain damage and death

o symptoms include
• convulsions
• dementia
• ataxia (balance and coordination dysfunction)
• behavioral or personality changes

o primary transmission unknown… may be ingestion

Friday, December 7, 2007

APES Environmental Toxins - Shope

ENVIRONMENTAL TOXINS



Mercury (Hg)
o manufacturing, mining, burning coal
o high levels in some fish (large predatory fish) due biomagnification
o neurotoxin… causes brain damage


Lead (Pb)
o paints, manufacturing, some gasoline
o neurotoxin (especially harmful to children)


DDT (DDD, DDE)
o insecticide
o systematic (general) poison – affects all systems in the body
o nervous system, liver, kidney
o now only used when approved… to combat very high risk of malaria


PCB
o electrical manufacturing
o high levels in some fish
o nervous system, thyroid, hormone problems
o still used… just controlled


Dioxin
o a family of 70+ chemicals
o pesticides, manufacturing, burning
o cancer, neurological problems
o “Agent Orange” - used in warfare to immediately kill forests
o kills rodents, insects, weeds


VOC
o volatile organic compounds
o higher levels indoors
o carpets, paints, cosmetics, cleaning fluids
o cancer, respiratory problems, neurological
o some are naturally produced by plants
o plants communicate via chemicals


asbestos
o insulation
o cancer, respiratory problems


heavy metals
o drinking water, pesticides, antiperspirants
o cancer, neurological problems
o can be released from soil/rock by acids

APES Health Toxins General Notes - Shope

HEALTH TOXINS




morbidity
o causing disease


mortality
o causing death (death rates)


toxins
o poisons/chemicals that have adverse health effects


toxicology
o the study of poisons


toxicity
o the measure of how harmful a poison is


• note: all chemicals can be considered toxins at some level



classes of toxins
o A – asphyxiants – toxins that interfere with breathing
o B – allergens – toxins that cause a physical reaction as an immune response
o C – neurotoxins – damage or paralyze nerves
o D – irritants – inflame skin or epithelial tissue
o e – mutagens – toxins causing damage to DNA
o f – teratagens – toxins causing birth defects
o g – carcinogens – cancer causing


LD50
o a measure of toxicity
o the amount of a chemical that will cause death in 50% of the a population
o usually measured in milligrams of toxins per kilogram of body weight
o ex.: give toxin to lab rat… this it the point at which 50% of them die


ED50
o the amount needed to have a certain effect on 50% of the population
o effect can be good (cure) or bad (headaches, nausea)


dose – response
o linear – slope depending on severity
o threshold – tolerance until a certain point… most substances have this

bioaccumulation
o an increase in the concentration of a chemical over time
o it occurs when a chemical is taken in faster than it can be eliminated
o usually occurs with fat soluble chemicals

biomagnification
o chemical becomes more concentrated as it moves up food chain
o ex.: the concentration of DDT in the fatty tissues of organisms in a food chain (studied by Rachel Carson)

Thalidomide
o 1960s
o popular in Europe
o came to US… approved by FDA
o given to pregnant women to fight nausea
o causes birth defects in children: teratagen
o was banned but is now being used (carefully) to treat some adult neurological disorders (?)

APES Infectious Diseases (STDs) - Shope

STDs


• sexually transmitted diseases

• bacterial – Chlamydia, gonorrhea, syphilis

• viral – genital warts, genital herpes, hepatitis B, AIDS

• #1 STD in US = Chlamydia… relatively curable (with antibiotics)

APES Infectious Diseases (fungal/parasitic) - Shope

FUNGAL / PARASITIC



o mycoses
• scientific term for fungal diseases
• can lie dormant for years until touched

o “curse of the pharaohs”
• scientists and tomb raiders opened tombs
• breathed in air full of ancient fungal spores
• got very sick


o worms
• 60% of human population of the world is infected with some type of worm… most: unknowingly
• some help (aid digestion, etc.)
• a parasite
• won’t try to kill host… it would die too

APES Infectious Diseases (protozoan) - Shope

PROTOZOAN



o malaria
• spread via mosquitoes
• living creature
• produces spores
• spores attach to liver
• destroys red blood cells
• not lethal for healthy person
• major killer for little children, babies
• about 110 kids/babies die each hour from malaria

APES Infectious Diseases (bacterial) - Shope

BACTERIAL



o tuberculosis
• TB
• #1 killer, as far as infectious diseases go
• was gone…
• is now coming back


o tetanus
• mostly gone in modern world
• “lockjaw”
• total muscle contraction


o typhus & typhoid fever
• typhus = lungs
• typhoid fever = diarrheal
• “disaster disease”


o bubonic plague
• #1 epidemic killer of all time
• “black death”
• killed 1 in 3 Europeans
• used in combat/war


o anthrax
• zoonotic (mostly cattle disease)
• attacks lungs
• not airborne
• big scare after 9-11


o cholera
• diarrheal
• infection of food, water
• mutates rapidly
• gets milder (or can get milder)


o leprosy / Hansen’s disease
• almost gone
• close to TB


o diphtheria
• “disaster disease”
• airborne
• blisters on lungs


o whooping cough
• fairly common
• respiratory


o lyme
• from tick
• 1st case in Lyme, Connecticut (hence the name)

APES Infectious Diseases (viral) - Shope

Infectious Diseases – major / historically significant / common / communicable (transmissible) disease

VIRAL



o HIV / AIDS
• number 2 epidemic disease
• can lie dormant for (long) time before becoming active


o Hepatitis (A, B, C, D, E)
• A – minor, relatively common… especially in children
• B & C – very serious
• D – very rare (often mutation of B or C)
• E – almost non-existent (has never been a case in the US)
• spread by… physical contact (with the exception of A: spread by ingestion… dirty food, putting dirty hands in mouth, etc.)


o smallpox
• now “extinct” (aside from some in a fridge in Atlanta, Moscow)
• transmitted by airborne virus
• used in combat/war
• officially announced that it was gone – 1980
• first disease for which a vaccine was developed…

o Edward Jenner
• British physician in the late 1700s
• traveled country healing people
• noticed that most girls (milkmaids) didn’t have smallpox
• they had contracted cowpox and developed immunity
• meanwhile… inoculation (smallpox: prick skin = immune?)
• Jenner heard about this
• took scrape of smallpox
• heated (weakened) sample then injected into healthy person
• 1st vaccine – 1790
• even vaccinated his own son
• “credited with saving more people than any other in history” (i)


o herpes
• about 8 strains known… HHV = “human herpes virus”
• is a retrovirus: viral DNA attaches to host DNA and becomes part of the genetic make-up of host
• HHV-1 – cold… cold sores = excess protein produced; permanent
• HHV-2 – genital herpes
• HHV-3 – chicken pox
• HHV-4 – Epstein-Barr (mononucleosis, “mono”, “kissing disease”)
• HHV-5, HHV-6, HHV-7 – cause rashes


o rabies
• one of the oldest known diseases
• no cure
• only preventative treatment soon after bite
• if not pretreated… most likely fatal: only one known survivor after the fact (and he had brain damage)


o polio
• mostly gone… few/none in the US in the last 40-50 years
• making a comeback
• devastating in US in 1940s/1950s
• nerve disease
• kills nerves “instantly” (within hours… go to bed fine, wake up paralyzed)
• ex.: FDR
• mostly children… killing or crippling
• Jonas Salk created plan to fight polio – completely “kill” (destroy all DNA) of virus before injection, not just weakening it
• still must be immunized before entering school


o cold / rhinovirus
• over 300 types
• can’t get the same type more than once
• no cure


o influenza
• zoonotic disease (we get it from animals)
• differs from year to year, depending on animal of origin
• most start in China/Asia
• current: avian flu… not yet airborne


o pneumonia
• can be bacterial or viral
• #1 killer of… people with immunological diseases (ex. AIDS), people with cancer, older people


o measles, rubella, mumps
• vaccine necessary before entering school: “MMR”
• rubella = “German measles”… mostly dangerous for pregnant women


o dengue – hemorrhagic fever
• causes bleeding… sometimes even through eyes
• very deadly
• 2 strains: 1 causes sickness, other immediately causes death


o Ebola
• causes bleeding
• very deadly
• has developed 5th strain
• not yet airborne
• mostly Africa (Zaire)


o yellow fever
• transferred via mosquito
• big problem in Central America
• vaccine was created so workers could build Panama Canal

APES Infectious Disease General Notes - Shope

For ease of formatting, this chapter is broken up into sections and different spacing and numbering has been changed. If you want me to send you a copy of the full notes in one document, just let me know!


5 classes of infectious disease
o A – blood borne – HIV
o B – respiratory – TB
o C – diarrheal – cholera
o D – parasitic – malaria
o E – contact - STDs

disease vectors (vector = a mode of transfer; how a disease is carried)
o insects – mosquito, tick, etc.
o water/food – usually intestinal diseases
o airborne – usually respiratory diseases

4 classes of pathogens (pathogen = anything causing disease)
o bacteria
o virus
o parasites – worms, fungus
o protozoans
o note: some chemicals cause disease but are classified as toxins

epidemiology
o the branch of medicine dealing with the study and control of disease

epidemic
o a widespread disease

pandemic
o an epidemic in a very wide area (a country or the entire world)

endemic
o (of a people); restricted to a local population or group

Lister
o late 1800s
o campaigned for more cleanliness on part of doctors
o (at a time when people didn’t worry about germs, etc.)

Tuberculosis (TB)
o #1 infectious disease
o has killed more people than any other disease
o a.k.a. “consumption”
o (more notes on TB later)

worst epidemic diseases… #1 = bubonic plague, #2 = HIV/AIDS

drug resistance
o MDR = multi-drug resistant
o DR = drug resistant
o MR = multi-resistant
o ex. – MRSA

Sunday, December 2, 2007

Phys Electrostatics Notes - Modine

Electrostatics


1. Electrostatic or Static Charge

2. Law of Charges
• opposites attract
• likes repel

3. Types of Charges
• positive
• negative
• neutral

4. Insulator
• object that electricity will not pass through
• has high resistance
• ex.: wood, rubber, pure water, plastic, fiberglass, glass

5. Conductor
• allows electricity to pass
• ex.: metals, silver (absolute best), silicon (computer chips)

6. Charging
• induction = charging without contact
• conduction = charging with contact
• grounding = electricity wants to find path of least resistance to the ground

7. Coulomb’s Law
• F = ( (k)(q1)(q2) ) / ( (r2) )
• F is F (sub e)
• k = constant = 9.0 x 109
• q = charge
• r = distance between charges

8. Charge of an Electron
• e- = 1.6 x 10-19 c
• c = Coulombs (unit for charge)

9. Total Charge
• Q = (N) (e-)
• Q = total charge
• N = 3 of e-

10. Electrical Field