Tuesday, August 25, 2009

This ad has been showing up on Canadian Airwaves this month. It is too good to not share with my American friends! I find it so inspiring and energizing. It send chills up my spine every time I see it. After watching it twice in a row on youtube, I was teary-eyed. A third time yielded real teardrops. It's amazing, and I love how it shows the power of hope and the human spirit in the face of tremendous adversity and once-bleak prospects. Each person in the ad is telling his or her own story: some are directly affected by illness, some are family members, and others are doctors, nurses, and researchers. Regardless, they have pulled together to help each other through it all, and that is something we can all do.





With an estimated one in three people to be diagnosed with cancer in our lifetime, it is something that all of us will likely have to pull together on at some point, in one role or another. Hope is essential.

The music choice was so appropriate - Verve's Bittersweet Symphony. Illness and loss are two of life's most bitter experiences, but through them, our capacity to understand and appreciate life's sweet moments is increased. One girl's story, "Cancer took my leg, but not my life", emphasizes this. Loss is part of life, and mourning those losses is an important step, but focusing on the good that remains will ultimately further our healing from loss and deepen our capacity for joy and appreciation of life and its sweet moments.

Tuesday, July 21, 2009

Harry Potter and Physcis

First off, let me alert you that if you haven't seen the new Harry Potter movie yet, you might not want to read on. I'm not going to reveal any huge plot twists or anything (and really, they're in the books anyway...), it will actually be quite insignificant, but if you like to be completely, totally, wonderfully surprised when you watch movies, this would be a good time to stop reading. Also, if, upon reading the title, you think that I might be about to discuss the intricate physical phenomena of levitation, apparition, spells, charms, etc., I'm sorry to inform you that you will be disappointed. There is just one small part that caught my eye...

So I saw HP6 this week, and it was great! I went with some friends who are also a little obsessed (in a good way!) with the books and movies, so it was lots of fun.

Right, so, on to the physics.

At one point near the beginning of the film, the Death Eaters are flying around London, causing havoc here and there. Nasty people, those Death Eaters. At one point, they began flying next to a suspension bridge that spans the Thames. The bridge started swaying back and forth and twisting, more and more violently until it snapped and collapsed. As this was happening, it reminded me of the Tacoma Narrows Bridge Disaster:



(there are a great many more videos on youtube about this bridge collapse, but I just chose the shortest one :) )

Basically (according to my physics professor), the wind gusting through the narrows (down the river, hitting the bridge), was not only powerful, but the gusts also occurred at a frequency that happened to be a resonance frequency of the bridge. This is the same principle that makes crystal shatter when a loud, high frequency noise (like a soprano's high note, lol) is sung. Instead of a glass, though, the bridge itself was resonating, and the strain caused it's collapse. Which is pretty cool, despite the destruction that it caused (for those who may be wondering, no person was killed or injured on the Tacoma Narrows collapse).

Anyway, so while watching the HP, and seeing the Death Eaters' flight around the bridge cause it to tremble, twist, bend, and eventually collapse, my thoughts wandered slightly, and I thought:

"Wow, those Death Eaters must be flying at exactly the resonance frequency of the bridge!"

There is no denying it now... I am a physics geek.

Monday, July 20, 2009

Oh, Joy

Well, my somewhat firm resolve to stop posting silly videos in lieu of actual posts has broken. Partly because I don't have too much to say, and partly because I think these next couple flicks are hilarious. And you all deserve a dose of hilarity in your days. Who am I to deny you that joy?

I loved watching the Muppet Show when I was little. I think, of all the members of our family, I loved it the most. I figure this to be true since I have memories of whining to keep the channel on the Muppet Show, and no one supported me.

Actually, it just occurred to me that that may have had nothing to do with their love for the Muppets, but rather with their disdain for my whining.

Hm.

Anyway.

One reason to love the Muppets is that they can take something serious or stuffy, like classical music, and make it accessible to more people. Exhibit A:



I love that the violin caught on fire... that is some intense friction.


Another great aspect of the Muppets is their ability to take cultural pieces and bring them to people of other nations. Exhibit B:




And I think that anyone who has played that song umpteen times in band will find that funny. I also love how Animal only seems to know the first few words: "Oh Danny Boy... oh... boy...". Which, can probably be said of a lot of people. "Oh, Danny boy, the pipes, the pipes are calling.... um... Danny... Boy...something something something." The words to the song really are beautiful, but I never would have known them if hadn't had a CD that happened to have that song on it. Funny how that happens. But we (as band people) can't be blamed - our job is to play notes, not sing words, and adding the words to our music would only cause confusion and missed cues.

Tuesday, July 14, 2009

Oops

As Teagan was kind enough to point out to me today, it's been two weeks since a post! Whoops.

Today has been an ok day, I had a biochemistry midterm this morning that was a little rougher than I'd like, but I think overall it went alright, and one can always hope for a grade curve. :)

This course is a 3-credit class science class, all crammed in to 3 1/2 weeks. The pace is definitely up! But I think it's just like tearing off a bandaid - sometimes it hurts less to get it done quickly, rather than dragging it out (the danger in this analogy is that, when applied to learning, it makes the lecture schedule a nightmare, assignment pace atrocious, and labs... every afternoon). It's going alright, though, so I can't complain about the course. About my lab partner, maybe, but... not about the course.

Speaking of which, I think I might start a writing project: a guide manual for science students on how to best irritate their lab partners. Given the extent of experience I have in this area (many times being the annoyed, and possibly also the annoyee on occasion ;) ), I'm sure I could have enough material for a great book (or at least a pamphlet). But that's only if I get really ambitious, which is not likely to happen, so... this guide will probably stay on the internet.

Here is some rough work so far...

Working Title: How to Annoy, Frustrate, and Drive your Lab Partner to Tears by Your Incompetence (She Didn't Actually Want to Pass This Class Anyway)

1. Be sure to show up to lab without having read the procedure beforehand. Reading is for losers, and you wouldn't want to show that kind of weakness. The *true* mark of a good student is being able to do experiments on the fly (even if this may mean having to repeat them when you add the wrong reagents).

2. In fact, don't even print out the lab procedure before coming to class. Having only one copy to work off of makes it much easier when both people need to be doing different parts of the procedure.

3. Marking glassware with a Sharpie makes clean-up a snap!

4. When holding a slide with neurotoxin on it, be sure to hold it over your lab partner's laptop so that when you space out and drop it, the liquid dribbles on to the keyboard. This is especially effective if you space out so much that you don't notice you have dropped the sample until your lab partner starts cleaning it up (yes, it was neurotoxin, but it was in its polymer form, so it wasn't dangerous. So I've been told... *twitch*).

5. Every so often, leave the lab without explanation for 20 or so minutes. While some lab procedures may leave you with down time while you wait for reactions to be completed, leaving during such times is almost expected. For maximum effect, leave the lab right before a complicated, time-sensitive procedure that can't wait needs to be done. Your lab partner will LOVE doing the work of two people herself. Come back at the next lull time, but don't offer any explanation as to where you might have been. Guessing games are fun!

I'm sure this will evolve as time goes on... and previously-repressed memories come back.

Naturally, any and all input from fellow students from their own experiences will be appreciated. :)

Tuesday, June 30, 2009

Concerned Children's Advertisers Strike Again

Maybe one of these days I'll stop posting videos of commercials I see on tv. Maybe one of these days, commercials will stop making me laugh hard enough to want to post them. Maybe one of these days, I'll just stop watching tv.

But until then, enjoy...





I love the music - it reminds me of Copland's Rodeo.

Study Break

So, I'm writing this, not because I'm taking a study break, but because it's about something that happened during a study break. I had a calculus final last Friday (and I am SO glad it's over! But that's another post... that I may or may not ever get around to writing), and spent all of Thursday in my room cramming. I started around 10:00 in the morning, and paused for some snacks here and there, but around 4:00, I decided that I needed to get outside for some exercise. This, of course, meant that I had to change out of my pyjamas. But I didn't want to put too much effort in to this, so I pulled on my gym shorts (ah, the Hart) and one of my bigger t-shirts (you know, the kind you wear to lounge around your house instead of out to the movies). Anyway, I set out for a walk/run through the neighbourhood, and it was really nice to get outside. It was a pretty warm day, so I was sweating in no time (not to mention my lack of physical fitness, haha). After a while, I realized that the people I was passing on the street were giving me some funny looks. I kept wogging (walk-jogging), and it kept happening. Finally I pieced it all together. The t-shirt I had happened to throw on is from my favourite bakery in Rexburg: The Cocoa Bean (they make the most amazing cupcakes and I miss them much more than is probably healthy). The t-shirt is red and looks like this:

And I realized that, from their perspective they see a pale, sweaty, out-of-breath girl wogging down the street, wearing an "I heart Cupcakes" shirt.

And I'm pretty sure at least one of them thought: "Well, there's your first problem".


Ba ha ha ha....

Anyway, also related to study breaks.... As much as living at home may not be my ideal situation right now, I have to admit that it's really, really, really nice when you're cramming away far into the evening and your mom knocks on your door and asks if you'd like her to make you a snack, coming back minutes later with a bowl full of fresh fruit on which to munch. Thanks, mom!

Sunday, June 21, 2009

So, I'm not trying to turn you all in to couch potatoes - really! I promise! But another funny ad came on today, and since it's Canadian, many of you may have NEVER seen it before. This is a tragedy, and evidently, I need to share it with you. More than one Canadian kid has, at some point or another, wanted a house hippo:



One of the best PSAs ever. :)

Wednesday, June 17, 2009

Re: video

also, I noticed that when I'm using tabs in Firefox, "YouTube" is shortened to "YouTub", which, considering it's being read by people who are spending wayyy too much time watching stupid videos on the internet, is probably a very appropiate statement.

So cute!

Alright, every time this ad comes on, it makes me so happy. I realize that perhaps it's a little strange to get so much joy out of 30 seconds of video designed to get me to buy gum, but... I can't help it. If you haven't seen this ad yet, you need to check it out. Actually, check it out anyway.



They're just so cute! I love the coffee cup at 0:14 - he's just sitting there, swinging his legs like he's so excited to be going for a car ride. Not to mention the fact that they got all buckled in and everything -safety first! And then they helped each other up the stairs. So, so cute.

Friday, June 12, 2009

Taxes (but no death!)

So, I just finished putting together my tax paperwork for last year. Since I was in the US for pretty much all of the year, I only had US taxes to file. Now, before anyone looks at their calendar, realizes that it is several weeks past April 15th, and has a minor heart attack on my behalf - don't worry! Since I'm no longer in the country, I have an extension. Until June 15th. Which is Monday. But I didn't leave it to the last minute - I have a whole 2 days until then!

Anyway, after finding my W-2 and 1042-S forms (I had put them in a "safe place" when I moved; a place so safe, I couldn't find them even when I wanted to), I got to work. Line 17, Box 2, add, deduct, etc. And I eventually found that I did, indeed, owe taxes on part of my income from last year: 9 dollars in taxes.

9 dollars.

What a stupid number!

On one hand, I'm certainly glad it's not any higher. On the other hand, it seems a little silly to have to pay such a small amount (I checked for any way out of it since the total was so small, but only when your total tax owed equals less than one dollar are you exempt from paying). So, Monday morning, I will head to the post office and file my taxes, along with a cheque for $9. The government certainly seems to want it. But I wonder what they'll do with it? What can the government of the United States of America buy with $9?
Some options:
  • nine packages of 10 HB #2 pencils
  • one mousepad
  • one tenth of a office chair
  • one fifteenth of a pothole repair
  • 6 minutes of a defense attorney's time
  • half of one person's business lunch
  • 5 gallons of jet fuel for Air Force One (yes, I checked the price of jet fuel)
In reality, the nine dollars will probably not be enough to pay the poor soul at the IRS who will process the paperwork. But it's still fun to imagine what to do with $9. Any ideas?

Sunday, April 12, 2009

This one's for you, Teags

This is at the Subway by Sonic in Rexburg. We stopped by to grab a bite to eat, and noticed that they charge for water. 27 cents. Not 25, not 30. 27.

Sunday, April 5, 2009

Conference Weekend!

Some of my favourite thoughts from conference this weekend...


Righteousness is measured not by our temptations, but by our resistance to them (Robert D. Hales)


Reverence invites revelation (Margaret S. Lifferth)


The sacrament meeting begins with the prelude music, not the opening prayer (Margaret S. Lifferth)


Don’t underestimate the power and influence that the youth in the church can have (Michael A. Nieder)


This is a great time to be alive (Allan F. Packer)


We can build again (D. Todd Christofferson)


We need to take care of each other (D. Todd Christofferson)


We cannot expect life to always be perfect (Henry B. Eyring)


Life is not meant to be fair or equal (Henry B. Eyring)

Things will work out (Henry B. Eyring)


Tragedy does not have to erode faith – it can strengthen it (Henry B. Eyring)


We need to learn to recognize and help those in need, even when we may need it more than they (Henry B. Eyring)


Our lives are examples to others (Quentin L. Cook)


Our prayers can be enhanced with the use of music, and fasting (Russell M. Nelson)


The road to eternal life is not a sprint, but a path of endurance (Dieter F. Uchtdorf)


Spiritual growth requires participation, not spectatorship (Dieter F. Uchtdorf)

Change is an essential part of life’s experience. (Steven E. Snow)

Be cheerful and optimistic (Steven E. Snow)


Learn to laugh – it will enrich your life, as well as the lives of those around you (Steven E. Snow)


The time is far spent (Barbara Thompson)


We need to take every opportunity to strengthen our families (Barbara Thompson)


Because Jesus walked His path alone, we do not have to walk ours alone (Jeffrey R. Holland)


Part of mortality is to be tried, but another part of it is to have joy
(President Monson)

The future is as bright as your faith (President Monson)


Forget yourself and go to work (Dallin H. Oaks)


We cannot do great things, we can only do small things with great love (Mother Theresa, quoted by Dallin H. Oaks)


Turn your homes toward the temple (Gary E. Stevenson)


Everything that leads us to do good is from God (José A. Teixeira)


May your homes be filled with harmony and love (Thomas S. Monson)

Blackberry Dump Cake

I made a very tasty cake this weekend, and I thought I'd share the recipe... and the story...

I got the recipe from Mrs. Oliver in Nachitoches (NACK-uh-tish), Louisiana, when we were there on tour. Grace and I stayed at the Oliver's home one night for homestay. Mr. and Mrs. Oliver, both in their eighties, were not members of the church, but had been meeting with the missionaries for a little while, and agreed to let us stay in their home. Mr. Oliver reminded me a bit of Dad, because as soon as we were settled in their home, he offered us a drink. Of beer. When we declined, he said (with a bit of a twinkle in his eye), "Oh, coffee, then?". He was hilarious. They were both so wonderful and kind.

Nachitoches! It was so beautiful and green, though it was just mid-April.

The chapel in Nachitoches, where we had a musical fireside.

Mrs. Oliver had made some cake for us, and it was so delicious, I had to ask for the recipe. She seemed surprised that I had never heard of dump cake before, so maybe it's a Southern thing. Many tasty foods are....

Breakfast at the Oliver's - biscuits, butter, molasses, sausage, and whole milk.

It's called "Dump Cake" because you really just dump all the ingredients into the pan - no mixing required! I didn't get a picture of the one I made because we ate it before I thought of my camera... which tells you how good it was! :)

2 1/2 cups of crushed pineapple (not drained)
3 cups fresh of frozen blueberries (I used blackberries because that's what I had in my freezer)
3/4 cup of sugar (we decided that this ingredient is probably not necessary... :) )
1 cake mix (yellow cake)
1/2 cup butter, melted
1 cup pecans (I used a mix of walnuts and almonds because, again, that's what I had)

Preheat oven to 350 F. In a buttered 9x13 pan, layer the pineapple, berries, and sugar. Add the powedered cake mix on top, and drizzle the melted butter on top of that. Sprinkle nuts over the top, and bake for about 45 minutes.

It's so good, and really easy. The only thing that I might change is that some of the cake mix didn't get "wet" with either butter or berry juice, so there were some dry spots. So next time I think I'll try mixing the ingredients a little in the pan, though that might disrupt the awesome cake layer that forms on top. We'll see... :)

Mr. and Mrs. Oliver (yes, I have forgotten their first names... sorry!)

Friday, March 27, 2009

Because I know your weekend won't be complete without it...

Here is the study guide from my most recent medical microbiology exam. And yes, it's 12 pages long. :)

Chapter 19 - Mechanisms of Bacterial Pathogenesis

1. Define each of the following terms: pathology, etiology, etiological agent, pathogenesis, colonization, disease, infection, pathogen, pathogenic, bacteremia, septicemia, toxemia, viremia, and reservoir.
Pathology – study of disease
Etiology – the cause of the disease (eg. The organism)
Colonization – bacteria growing in the body
Disease – change from a state of health
Infection – colonization with a pathogenic bacterium
Pathogen – disease-causing agent
Pathogenic – adj. for pathogen
Bacteremia – bacteria in the blood
Septicemia – bacteria growing in the blood
Toxemia – toxins in the blood
Viremia – viruses in the blood
Reservoir – where the pathogen “hangs out” naturally.

2. What is normal flora? Explain how normal flora could be categorized as: mutualistic, commensal, or opportunistic. What is a parasite?
Normal flora is the colonization of bacteria in out body that is normal and not harmful. They contribute to microbial antagonism, and may synthesize nutrients such as vitamins that help us.
Mutualistic – both benefit
Commensal – one benefits
Opportunistic – NF takes advantage of suppressed immune system to cause infection in an unusual location
Parasite – one benefits, other is harmed

3. What is the germ theory of disease? What are Koch’s Postulates? What are they used for?
Germ theory – germs cause disease. One germ, one disease.
Koch – to prove which microorganism is the causative agent of the disease
Isolate sample from infected individual
Culture
Infect new individual
When signs and symptoms develop that are the same as the first infected individual, the organism is the same, and can be concluded to be the causative agent.

4. Describe how each of the following is used to describe a disease (and explain what the term means): communicable, contagious, noncommunicable, endemic, epidemic, pandemic, acute, chronic, and latent.
Communicable – can spread from person to person (HIV)
Contagious – spreads easily from person to person (rhinovirus)
Non-communicable – cannot be spread from person to person (tetanus)
Endemic – at a consistent rate of infection
Epidemic – spike of infection rate in a given area
Pandemic – disease is worldwide
Acute – rapid onset, severe, then finishes
Chronic – slow onset, prolonged illness
Latent – person is a carrier, but shows no symptoms. Can flare up (varicella)

5. What is the difference between a local infection and a systemic infection?
Local – confined to one area
Systemic – whole body

6. What is the difference between a primary infection and a secondary infection? What is a subclinical infection?
1ary – first infection
2ary – infection after the 1ary, more susceptible to it bc of weakened immune system
Subclinical – no symptoms

7. Describe the following mechanisms of disease transmission: contact transmission (direct, indirect, and droplet), vehicle transmission, and vector transmission.
Contact:
Direct – person-to-person
Indirect – through an inanimate object
Droplet – cough, sneeze
Vehicle – food and water
Vector – insect bite

8. What is a fomite? What is a nosocomial infection?
Fomite – for indirect transmission
Nosocomial – acquired in a healthcare setting

9. What is epidemiology?
Study of frequency and distribution of disease.

10. What is the Center for Disease Control and Prevention (CDC)? What types of things does this agency do?
National Epidemiology Center (USA). Tracks infectious diseases, helps local health agencies during outbreaks. Publishes monthly reports.

11. Describe the sequence of events successful pathogens carry out.
Transmission to host, entry into tissue, adherence to target tissue, invasion/evasion, host damage, exit, transmission.

12. What are portals of entry? What are the possible portals of entry for pathogens?
PofE are where the pathogen gains entry to the host. Usually: mucous membranes (GI, GU, respiratory), parenteral, skin.

13. What are virulence factors? How does each of the following function as a virulence factor: adhesions, fimbriae, biofilms, capsule, cell walls of mycobacteria, toxins, and enzymes?
Adhesins – help bacteria stick to host tissue. Fimbriae and pili.
Fimbrie – “ “
Biofilms – glue to surfaces
Capsule – evade phagocytosis, poorly antigenic
Mycolic acid – evade phagocytosis
Toxins – host damage, direct (exo) and indirect (endo)
Enzymes – kinase, coagulase, hyaluronidase, collagenase, IgA protease.

14. Give the function of each of the following enzymes and explain how they can aid pathogens in causing disease: hemolysins (both α and β hemolysins), leukocidins, streptokinase, staphylokinase, coagulase, collagenase, proteases, hyaluronidase, and phospholipase C.
Hemolysins – lyse RBCs
α – complete lysis
β – partial lysis
Leukocidins – lyse WBCs
Strepto/staphylokinase – break down blood clots, gain entry
Coagulase – formation of blood clots, wall off from WBCs
Collagenase – break collagen, get deeper into tissues
Protease – break down specific proteins, eg. IgA protease.
Hyaluronidase – break down hyaluronic acid, get deeper into tissues
Phospholipase C – hydrolyses lecithin (in tissues)

15. What are exotoxins? List the examples of the following types of exotoxins discussed in class and explain how they affect the host: cytotoxins, enterotoxins, and neurotoxins.
Exotoxins – released by the cell. Usually G(+), but can be G(-).
Cytotoxins – damage cells
Erythrotoxins – damage to capillary cells, cause blood to leak out (S. pyogenes)
Enterotoxins – damage to GI -> diarrhea, vomiting, etc. (Cholera, S. food poisoning, bacterial dystentery)
Neurotoxins – inhibit normal NT flow (Tetanus, Botulinum)

16. What is endotoxin? How does it affect humans?
Made by G(-) cells, is the LPS in the outer membrane. Once ingested by phagocytes, LPS is relased, stimulating cell to release cytokine IL-1, which reaches hypothalamus. Resets the “thermostat”, h-thal. Releases prostaglandins to initiate the fever response (vasodilation, vasopermeability, high temp.). Can lead to shock due to decrease in BP from vasodilation.

17. How do the following help bacteria evade the immune system: antigenic variation and inactivation of antibodies or complement?
AV – evade immune system’s antibodies
Inactivation – cascade/signaling system is disrupted

18. What are cross-reactive antibodies? How are they involved in damage to host cells?
Antibodies produced in response to an antigen, that undergo slight variation in the final differentiation process, that are similar enough to our own proteins to elicit an inflammatory response against our own tissues. Strep throat -> rheumatic fever, glomerulonephritis. Heart valves & strep. Antibiotics are prescribed with Strep. Infections not to help clear up the infection (which will subside in a few days), but to prevent the formation of antibodies that could attack our own cells.

19. What are superantigens? How are they involved in damage to host cells?
Antigens that are repeating polysaccharide units, stimulate non-T-cell-specific activation of the immune system, large cytokine release -> shock. Can get out of hand quickly, lead to death. Toxic shock syndrome (S. aureus).

Chapter 20 - Antibacterial Agents

1. Briefly describe the history of the antibacterial agents Protosil (sulfanilamide) and penicillin.
Protosil (sulfas) – 1935, used first in mice to treat systemic strep. Protosil is cleaved in the body to produce sulfanilamide, the active agent.
Penicillin – Alexander Fleming – Penicillium mold prevented bacterial growth on a plate.

2. Are all antibacterial agents antibiotics? Why or why not?
No – antibiotics are, by definition, made by other microorganisms. Some antibacterial agents, like the sulfa drugs, are made in the lab.

3. Describe the property of selective toxicity. Why is this an important property of antibacterial agents?
Selective toxicity means that the drug is selectively harmful toward the pathogen, and not our own cells. This is important because we want to maximize damage to pathogens while minimizing damage to our cells.

4. What is the difference between broad-spectrum and narrow-spectrum drugs? Under what conditions would each type of drug be used?
Broad – affects all, used when ID in unknown
Narrow – affects some, used when ID known, to protect NF

5. List the various targets of antimicrobial drugs and give which types of drugs have each type of target. (Those listed in Figure 20-1 and those discussed in class).
Cell wall synthesis
Penicillins
Cephalosporins
Beta-lactams
Isoniazid
Ethambutol
Cycloserine
Ethionamide
Bacitracin
Polymixin
Protein Synthesis
30S:
Aminoglycosides
Tetracyclines
50S:
Chloramphenicol
Macrolides
Clindamycin
Linezolid
Quinupristindalfopristin
DNA replication
Quinolones
Metronidazole
Clofazimine
RNA synthesis
Rifampin
Rifabutin
Antimetabolites
Sulfanamides
Dapsone
Trimethoprim
Para-aminosalycylic acid

6. What are Beta-lactams? What do they do to kill bacterial cells?
Î’-lactams are rings in the structure of antibiotics in the penicillin and cephalosporin families. They inactivate bacterial enzymes used in the synthesis of peptidoglycan. Without p-glycan, the cells cannot replicate.

7. What would be a problem with drugs used to fight fungal infections?
How about those used to fight viral infections?
Fungal – harder to crate drugs with selective toxicity as fungi are eukaryotic cells. More in common structurally, so harder to target.
Viruses – spend little time outside of host cells, hard to detect and target. Don’t carry out metabolism, so not “cell” processes to target.

8. List and describe the mechanisms of antibiotic resistance. What are beta-lactamases?
Destroy the drug (lactamases)
Altering drug target site
Increase drug elimination from cell, host
Alter permeability to drug (more impermeable)
β-lactamases are enzymes that break the β-lactam ring of antibiotics in the penicillin and cephalosporin families.

9. How is resistance to a drug acquired?
Begins with spontaneous mutation, and spreads through plasmid transfer (pili, phage conversion).

10. What human practices lead to antibiotic resistance in bacteria?
Overuse of antibiotics
Use by immunosuppressed individuals
Patient noncompliance
Animal feed

Chapter 22 –

Staphylococcus organisms

G(+) coccus. Facultative anaerobes. Tolerate high salt (resistance to osmotic pressure).
S. AUREUS – COAGULASE+

Virulence – capsule, peptidoglycan, teichoic acid, protein A, cytoplasmic membrane, toxins – exfolitoxins, enterotoxins, TSS superantigen, cytotoxins; enzymes: coagulase, catalase, hyalurondiase, fibrinolysin, lipases, nucleases, penicillinase

Epidemiology – NF skin, nares. Survive on dry surfaces, fomite spread.

Diseases
Staph. Scalded Skin Syndrome (Ritter’s) (destroy connective tissue between dermis and epidermis, epidermis falls off. Exfolitoxins).
Bullous Impetigo – blisters on skin
Food Poisoning – heat stable toxin
TSS – high mortality
Folliculitis – hair follicles infected (“ingrown hairs”?)
Furuncle (boil) (site of draining pus, must be drained (will not clear up))
Carbuncle (several sites of draining pus)
Pustular Impetigo
Bacteremia
Endocarditis
Pneumonia
Osteomyelitis – infection in bone, from bacteremia or spread of wound
Septic Arthritis

ID: Gram stain, catalase, coagulase, mannitol fermentation.
Treatment – penicillin resistance is common


Chapter 23 – Streptococcus
G(+), chains, fac. Anaerobes, some are aerotolerants. Produce lactic acid. Catalase (-). Complex nutritional requirements.

Virulence –
Capsule – mimics hyaluronic acid
M proteins
Heart valve protein (rheumatic fever protein)
Blocks C3B
Toxins – erythrogenic
Streptolysin
Type S – aerobic conditions
Type O – anaerobic conditions
Streptokinase
Breaks down blood clots

Epidemiology
Oropharynx and skin – children and Young adults
Transmitted through direct contact (infected mucus, body secretions)
Asymptomatic patients, pts on antibiotics are less contagious
Noninvasive disease is common
Over 10 million cases, underreported
Most common : pharyngitis, pyoderma

Diseases –
Suppurative (development of pus)
Pharyngitis (strep throat)
2-4/365 incubation
cannot diagnose visually
Complication : Scarlet fever
Pyoderma (Impetigo)
S. aureus
Erysipelas
Acute skin infection
Systemis signs (fever, chills…)
Cellulitis
Inflammation of connective tissue
Bacteremia
40% mortality
Necrotizing Fasciitis
Streptococcal gangrene
Destroy muscle, fat, skin
25% mortality
Streptococcal toxic shock syndrome (STSS)
Superantigens
Often accompanies NF
45% mortality

Non-suppurative (no pus)
Rheumatic Fever
Complication of pharyngitis or skin infections, may have had asymptomatic infection
Prevented with antibiotics
Cross-reactive antibodies
Inflammation in heart, joints, blood vessels, skin
Affected individuals are more susceptible to further infection/damage
Actue glomerulonephritis – damage to glomerulus, causes blood in the urine

ID –
S.pyogenes :
Group A
G(+)
blood agar
PYR enzymes (differentiate b/t S. pyogenes, S. anginosus)
Antigen detection – rapid strep test

Treatment –
Penicillin
Macrolides
NF – surgery
Rheumatic Fever – preventative antibiotics
Wash hands, etc.

Ch 23 b

Strep. agalactiae

Group B strep

Characteristics-
G(+) streptococci
Facultative anaerobe
Beta-hemolytic (Small percentage non-hemolytic)
B antigen

Virulence –

Epidemiology –
Site : lower GI tract, GU tract
10-30% of pregnant women are carriers
60% of infants born to infected mothers become infected
In men and non-pregnant women :
Skin and soft tissue
Bacteremia
UTI/urosepsis
Pneumonia
Predisposing factors :
Diabetes mellitus
Cancer
Alcoholism

Diseases –
Puerperal sepsis (childbed fever)
In newborns : Septicemia, Pneumonia, Meningitis
Early-onset neonatal disease (1/52)
Acquired in utero or at birth
Bacteremia, pneumonia, meningitis
Must examine CSF
5% mortality
15-30% of survivors have permanent neurological damage –
blindness, deafness, severe mental retardation
Late Onset Neonatal disease(1-12/52)
Source : mother, other infants
Bacteremia, meningitis
Pregnant Women – UTIs
Men and non-pregnant women
In immunocompromised individuals
Bacteremia
Pneumonia
Bone and joint infections
Skin and soft tissue infection
15-32% mortality

ID –
Culture
Antigen detection
PCR

Treatment –
Penicillin G
Pregnant women – IV of antibiotics before delivery, can cross placenta, offers defense if colonized by bacteria

Viridans Streptococci

Characteristics –
Heterogenous collection of alpha-hemolytic and non-hemolytic strep. Spp.
20 spp. In 6 groups
Req. complex media, blood products, 5-10% CO2

Colonize
Oropharynx (NF)
GI (NF), GU

Diseases
Dental caries
Subacute endocarditis
Not from Ig, but from bacteria. The viridans bind to damaged (congenital, superantigen) heart valves. Transmitted during dental work.
Suppurative intraabdominal infections

Treatment
Penicillin
Some resistant strains

Strep. pnuemoniae

Characteristics -
G(+) coccus, large cells, oval/lancet shape
Also called diplococcus, pneumococcus
Fastidious requirements
Alpha-hemolytic in aerobic
Beta-hemolytic in anaerobic
Catalase (-)
Poor growth in high glucose
Prominent capsule

Virulence factors
CAPSULE

Epidemiology
Enodgenous (NF)
Direct transmission is rare
Often a SECONDARY infection
Young and old at higher risk (meningitis)
More common in cool months

Diseases
Sinusitis & Otitis media
Over 7 million cases/year
Paranasal sinuses and middle ear
2ary to viral infection in upper respiratory tract
Sinus – all ages
Otitis media – young children
Eustacian tube is shorter, bacteria can travel more easily to middle ear. Opening more narrow, closes off more easily. Closes off, fluid accumulates, puts pressure on tympanic memrane, can rupture eardrum (can heal), break malleus/incus/stapes -> hearing loss.
Meningitis
6000 cases/year
Mostly in children
More damage than other types of meningitis

Bacteremia
55000 cases/year
Endocarditis, even with previously undamaged heart valves

Identification

Treatment
Penicillins and others
Immunization


Ch 24 – Enterococcus

Characteristics
Originally group D strep
E. faecalis
E. faecium
Catalase (-)
Fermentation
Tolerates high salt, bile salts
Commensal organism in large intestine
High antibiotic resistance
Infections : endogenous source

Transmission
Person-to-person
Contaminated food

Virulence Factors:
Multi-drug resistance
Colonization
Secreted factors

Diseases
Risk factors:
Catheterization
Long-term hospitalization
UTI (especially w/ catheter)
10% of all nosocomial infections
Vancomycin- Resistant Enterococcus (VRE) 35-50% mortality
Peritonitis (after surgery)
Endocarditis (5-15%)
Bacteremia
Wound infections, abcesses

Treatment
Highly resistant
25% resist aminoglycoside
50% resist ampicillin
25% resist vancomycin

Monday, March 16, 2009

I saw this sign today as I walked up from the Hart toward the MC. There have been quite a few problems recently at crosswalks (both drivers not paying attention and pedestrians wandering all over the place). The school has been working with the city to try to remedy this (including drumroll..... fixing the crosswalk signals on 2nd South!! I thought I would never live to see the day! Especially the way the cars barrel through that intersection).

I guess this sign is one of the other ways they are increasing awareness. I read it as I walked by, thought about it while walking, started to laugh nearly out loud, and turned around to take a picture. "Use crosswalks!" "Share the Road!" But it's the caption at the bottom that gets me "think of the impact you can make". Um... I thought the idea was to NOT make an impact.

Hehe.

Saturday, March 14, 2009

It's Saturday!!

I was so excited to wake up this morning and to not have to be anywhere any time soon. It's nice. I spent the night at Katie's again, and am convinced that she has the Best Couch in the World. Really! Today was the first day since Wednesday that I haven't woken up with a migraine (which is weird, because I really haven't gotten them lately at all - the last one before this week was on tour with the Symphony Band in April). So, I am giving credit to the couch. :) I met Katie at her work last night so we could head over to her apartment together. She works at Hogi Yogi, which is a bit of a Utah-Idaho institution... but is basically a fast-food type place, but a little higher up than McDonald's. Anyway, they had some drama there last night - someone graffitied one of their booths. They have security cameras, though, so they'll be able to figure out who did it (only a few people sat at that bench last night). We were talking about it afterward, and just thought it was a little funny - the graffiti was a gang tag (which in and of itself isn't funny), but... a gang tag in Rexburg? Borderline hilarious. What, are they having drug territory wars? It was probably just some 14-year-old who was trying to be cool. Anyway.

I've been thinking of what to do next year... I know I'll be home for a while, but I'm trying to figure out a more long-term plan. I still think that med school is the way to go for me, but I just may have to take a different route to get there. So I'm starting to think of what I need to do to make myself a stronger applicant for next year, and also thinking about possible master's programs. It's a little hard, because I don't have a strong interest in research (last summer cured me of that, haha... sigh), but many programs focus on that. I really just want something that will help me gain a better understanding and perspective in medicine and prepare me for med school. I started thinking about bioethics, which I think would be really neat. The only catch is that there seems to be only one program in all of Canada, at the U of T. And Toronto is a nice city, but... I guess it would just be nice to have a few more options. There are some online master's programs, but I'm pretty wary of those and how useful they would prove to be in further studies and jobs. Another program is a master's of public health, which would be really cool. BYU (Provo) has a great MPH program, and for part of it you get to work in an underdeveloped area of the country or the world and implement a program that you help design (eg. stop smoking program, patient education programs, etc). Which I think would be an A-M-A-Z-I-N-G opportunity! But let's be honest... I'm not sure I could handle Provo! Haha... I guess I'll have to think about things a bit more.

Sometimes I just want to forget about it all and go to law school instead. Sometimes I want to forget it all and be a bum on the street, but of those two options, I'm pretty sure my parents would disapprove of the latter.

Or maybe the former. ;)

Thursday, March 12, 2009

So things have settled down a little... the two roommates who were kicked finally *moved* out this week. It was pretty tense until they did, but things have been ok since then. And by "ok", what I really mean is "no one is openly hostile". Which is a nice change, but... still a far cry from what would be nice. Anyway, I am glad things are a little better.

I had a good day in the ceramics studio, I was able to get some work done and am really happy with hoe it turned out. We did a Raku firing in class today, which was a lot of fun. With Raku, when the pieces are fired and really hot, you pull them out of the kiln and then set them in bins that are full of sawdust, newspaper, and other combustibles. The pieces are so hot that they ignite the material, and the ash produced gives the piece a cool finish. I'm hoping to Raku fire a piece next week. The ones done today were really beautiful. The only drawback is that the pieces don't get hot enough to vitrify, and they remain porous, so you can't use them to hold food or water. But I think I'll still give it a shot. I'm hoping to find a ceramics studio in Winnipeg so I can keep up with it after graduation.

Wednesday, March 4, 2009

Untitled 4, 2009.

I think sometimes things get worse before they get better.

This appears to be one of those times.

But my religion professor (Brother Ferguson) shared something today that I thought was applicable... "The difficulties proceeding the decision are evidence of the correctness of that decision". It's a cruel fact of life that doing the right things can often times land you in more hot water than doing the wrong things. But, at the end of the day (okay, actually wayyy more long-term than just one day), the frustrations and difficulties of life will seem small compared with the person you have become through them. It's just the going through part that stinks. ;)

I'll be at Katie's tonight.

Tuesday, March 3, 2009

Ta-da!

My first finished piece!

The glaze on the outside is blueish, and the inside glaze is sort of a rusty colour. They're both speckly, which is fun. I'm rather proud of it. It was a little harder than I thought it would be to get the glaze to stay where I put it, so it ran around a bit, but it turned out looking neat anyway. It definitely takes a while to get a piece from start to finish - shaping can a take a while, depending on what you are making and if you are adding any texture details, and then it needs to dry. Once dry, it goes in for bisque firing, and then you can put a glaze on it. It is then fired a second time (and at a much higher temperature), and this actually turns the glaze and some of the minerals in the clay to glass. After the second firing, the bottom of the piece (that didn't get glazed) needs to be smoothed out, since the clay gets really rough. You can't put glaze all the way to the bototm egde of the piece because it would run down off the piece and onto the kiln, and when it cools = HUGE MESS.

So I glazed another piece today, and hopefully it will be out of the kiln soon (firing takes a couple days). I realized that I need to get working on things for this class- our final is to present 6 finished pieces (good ones... haha), and since it takes a little while to get it all done, I really should get moving on it. I haven't glazed my bird's nest yet - it got a crack in it that I need to fix, and it's going to take a large chunk of time to do that. So maybe this Saturday will be a ceramics day... :)

Monday, March 2, 2009

This is a little late...

So, my amazing sister-in-law Jess tagged me in a post of hers in February, and because I am kind of a blog slacker sometimes (ok, most times, excepting random bursts of creative energy like I've had this week), I haven't done it yet. Sorry! I'm supposed to write six random things about myself and then tag others to do the same. So... here goes!

1. I am currently eating a grape popsicle. The popsicle stick has a joke on it - it asks you a riddle question on the "dry" end, and then when you finish the popsicle, you get the answer. They're always really lame, but I like them anyway, and try to guess what the answer will be. Today's joke is "What has wheel and a trunk but no engine?" I'm going with "An elephant on roller skates".

2. I had the biggest group session at work EVER today. I had 7 students at once, and while it was different from what I was used to, and I had to modify my teaching style a bit, it was really good and we got through a lot of material. The students were able to feed off each other and quiz each other a lot, which was great. The best part of work is helping things "click", and that happened a lot today, so it was a good day.

3. Sometimes I get really motivated and excited about cooking and trying new recipes, but I'm gradually coming to admit and accept that invariably, when I get to the store with my beautiful list of necessary ingredients, it all seems too daunting and expensive, and I start thinking of everything adding up and all the chopping and measuring and cooking involved, all for a recipe that may not even be tasty. Eventually I give up and buy bread, peanut butter, and noodles. Or, worse yet, I buy half the ingredients and let them sit in my pantry, unused and unloved. I need to figure out what to do with that curry mix....

4. I rarely read the school newspaper because it makes me too angry. We're in college, people! Grammar should not be a complicated issue! And WHERE was the editor?!?! The writing also tends to be very poor in content. Last week there was an article about vegetarianism (anti-veg), and the writer used the President of the Cattleman's Association as her main source. Um... I'm sure he's a nice guy, but I'm also sure there *may* be some bias. Just sayin. I would have written a letter to the editor, but I was too irritated to be articulate. Haha.

5. I love white boards. I carry dry erase markers in my backpack! I justify it by saying that I use them for work (you know, so the students can draw things out on the boards...), but let's be honest... I use them more than they do. They're just perfect for drawing out cell processes and chemical pathways! And they come in such pretty colours.

6. I actually like all my classes this semester. Even if I don't enjoy every minute of them, or all the work I have to do for them, I am learning about lots of different things (Music, Ceramics, Medical Microbiology, Doctrine and Covenants, and Political Science), and it's all interesting. I think the trick is that I feel like they can each apply to or contribute to my life in some way, even if I have to get a little creative in establishing the connection sometimes... haha.

I guess that's it... and now, I'm going to tag... Teags, Romy, and Theresa. But no worries if you take a month to reply like I did. :)

Oh, and the answer to the riddle... "An elephant on rollerblades"!
I know, I know... I was off on the roller skates/rollerblades thing (kids these days... always having the new toys...) but I'm still counting it. Which means... I'm awesome!!! Either that, or I have eaten far too many of those things and now just know the type of humour they use. That's a scary thought.

Sunday, March 1, 2009

Ok, one more update...

I came home last night after going to the grocery store (thanks, Judy Kay!). I was pretty tired, so I just had a nice warm bath and went to bed. I got up this morning and it was pretty quiet, but I was ok with that. I needed to make a phone call to another girl in our ward, so I went to got our ward directory. I discovered that in the time I was gone, someone had drawn horns and a tail on our Bishop's picture. Seriously. It irks me on so many levels! First, yes, this is the maturity level I'm dealing with. Second - he's the Bishop! Way to sustain church leaders... sigh.
Two of my roommates (the two I wrote about yesterday) came home from meetings this morning (I think, I didn't get the details). They gave the news: kicked out of school, and have to be gone by the end of the week. I feel as though I should feel at least a little sad for them, but I don't. They were given so many chances to fix things and change, but all they could see was someone "telling them how to run their life". I guess that's the sad part.

Anyway, I'm sure I'll sort my feelings out on this sooner or later and then be more articulate about it, but until then...

I'll probably be at Katie's house.

Saturday, February 28, 2009

You don't actually have to read this... I just thought it would be funny to post. I'll bet you wish you were a bio major, too! ;)

Medical Microbiology

Chapter 6 - Viral Classification, Structure, and Replication

5. Describe the steps of viral replication. Be sure to differentiate between the events of naked viruses and enveloped viruses that have DNA or RNA genomes (including positive and negative sense RNA). Also explain the replication of retroviruses.

Enveloped - insert proteins into membranes, assembled at membrane.

Chapter 7 - Fungal Classification, Structure, and Replication

1. Describe the basic structure of a fungal cell. Why is it difficult to develop anti-fungal medications?
Eukaryotic. Cell wall is made of chitin and glucan, has ergosterols. V. similar to our cells (80S ribosomes, ER, Golgi, etc.).

2. Describe or define the following: yeasts, pseudohyphae, molds, hyphae, mycelium, dimorphic fungi, mycosis, dermatophytes, and thermal dimorphism.
Yeasts – single cells.
Pseudohypahe – strips of yeast cells together
Molds – multicellular
Hyphae – long “strings” of cells in the fungal structure
Mycelium – many hyphae woven together to create a “mat”
Dimorphic – can switch from yeast to mold and back
Mycosis – fungal infection
Dermatophytes – fungi that cause disease in the skin (cutaneous fungal infection)
Thermal di – switch from yeast to mold caused by change in temperature

3. Briefly describe each of the following types of fungal infections: superficial mycoses, cutaneous mycoses, subcutaneous mycoses, endemic mycoses, and opportunistic mycoses.
Superficial – not harmful, cosmetic only. Very rare
Cutaneous – v. common, infection of skin, nails, hair.
Subcutaneous – deeper tissues
Endemic – thermal dimorph fungi, seen in healthy people (abcesses, ulcers)
Opportunistic – seen in immunocompromised individuals. Normally non-pathogenic.

4. What specific types of infections do the following fungi cause: Candida spp., Cryptococcus neoformans, and Aspergillus spp.?
Opportunisitc.

5. Disease of the Day - "The Terminator" article
Mucormycosis – in the sinus. Feeds on sugar, so elevated risk for diabetics.

Chapter 9 - Commensal and Pathogenic Microbial Flora

1. What is normal flora?
Does not cause disease, often helps us. Takes up space and nutrients (microbial antagonism).

2. Define the following terms: transient colonization, permanent colonization, disease, strict pathogen, and opportunistic pathogen.
Transient – comes and leaves
Permanent – is always there (eg. Staph on skin)
Disease - change from a state of health
Strict pathogen – always causes illness
Opportunistic – may cause disease, depends on location

3. In what ways do pathogens cause damage to host tissues?
Toxins, resource use, damage cells, secrete enzymes like collagenase and hyaluronidase that damage connective tissues.

4. List the normal flora and pathogens discussed in class for each of the following body sites: mouth, oropharynx, nasopharynx; external ear; lower respiratory tract; esophagus; stomach; small intestine; large intestine; anterior urethra; vagina; and skin.
Oropharynx – anaerobes, strep, neisseria,.
Nasopharynx – straep and staph
Ear – staph and pseudomonas
Resp. – strep aureus, pneumonie, klebsiella
Eso – none
Stomach – lactobacillus, h. pylori
Intestine – salmonella, e coli
GI system – lactobacillus, candida, N gonorrhoeae, chylamidia
Skin - pyogenes

Chapter 10 - Sterilization, Disinfection, and Antisepsis

1. Define the following terms: sterilization, disinfection, disinfectant, antisepsis, antiseptic, sanitizer, germicide, bactericide, and bacteriostatic agent.
S- all dead
Dis- mostly dead
Anti- used on living tissue
Sani- dis. Used on food equipment
Germicide – kills bacteria
B-static - inhibits growth of bact.

2. Describe the rate of microbial death when treated with a physical or chemical agent.
Affected by factors such as exposure length, chemical used, individual susceptibility, environment, etc.

3. How do things like heat and disinfectants kill bacteria?
Damage cell membranes, cell proteins.

4. Describe the following methods of controlling microbial growth (be sure to include the most common uses and benefits or limitations of each method): moist heat, autoclaving, boiling water, pasteurization, Ultra High Temperature (UHT) treatment, dry heat, flaming, low temperature, filtering, ionizing radiation, UV radiation, Ethylene Oxide Gas, aldehydes, hydrogen peroxide, halogens, alcohols, chlorhexidine, and triclosan.
Moist heat – v. good. Common. Kills all.
Autoclave 0 type of moist heat
Pasteurization 0 use moist heat to kill some/many of pathogens in food/liquid
UHT – for food, sterilizes milk – no fridge needed.
Dry heat – kills, but not as fast
Low temp – slows growth
Filter – removes pathogens
Ion – x and gamma rays. Kills. Used on equipment
UV – used in rooms
Ethy gas – instruments
Aldehyde – eg. Formaldehyde
H2O2 – oxidizes
Halogens – proteins
Alcohols – membranes
Chlor and tri – in soaps

Chapter 11 - Elements of Host Protective Responses

1. List and describe the 3 layers/walls of defense against pathogens and toxins. What are the elements of each layer?
1st – barriers such as skin, mucus menbranes and secretions (lysozyme, tears, fatty acids, lactic acid, stomach acid)
2nd – innate – non-specific. Complement pathways, imflammatory response, phagocytosis, NK cells.
3rd – Ig-mediated. Specific. Actions of B and T cells.

2. Describe the activities of each of the following chemicals that allow communication between cells: cytokines, interferons, and chemokines.
Cytokines – for immune response
Interferons – anti-viral, from cell to cell, stimulate immune response.
Chemokines – inflammatory response

3. Give the function(s) for each of the following cells: Natural Killer cells, neutrophils (polymorphonuclear cells or PMN's), eosinophils, macrophages, monocytes, dendritic cells, Langerhans cells, microglial cells, Kupffer cells, B-cells, memory B-cells, T-cells (both CD4/helper cells and CD8/cytotoxic cells), memory T-cells, plasma cells, basophils, and mast cells.
NK cells – kill cells with Ig on them and virus infected cells and tumor cells. No MHC use.
Neutrophils – phagocytosis
Eosiniphils – parasite defense, allergis response – (IgE)
Macrophages – phagocytosis, antigen presentation, imflammatory response
Monocytes – phagocytosis, APC
DC – APC
Langerhans – antigen transport to lymph nodes
Microglial – cytokines production, APC
Kupffer – filter particles from blood
B – Ig production, memory.
T – help activate B and TC, Tc kills infected cells
Memory T – type of CD8
Plasma – produce Ig (types G, E, A)
Basophils and MAST– histamine, allergic response, IgE receptors.

4. What does "CD" stand for (as it applies to cells in the immune system)? What is the MHC? What cells have MHC class I molecules? What cells have MHC class II molecules? What do these proteins do?

Cluster of Differentiation
Major Histocompatability Complex
All cells
Antigen-presenting cells (APCs) - macrophages, dendritic cells, B cells (different case - can't activate CD4 cells)
MHC proteins display the antigens on the outside of the cell. Class I and II are receptors for different reactions.

5. Describe the structure and function of the following lymphoid organs: lymph nodes, spleen, mucosa-associated lymphoid tissue (MALT), Peyer's patches, and tonsils.
Nodes – little “balls” that the lymph travels through as it is transported to be put back into the blood. Helps Macrophages meet up with B and T cells to help the immune response connect. Three parts – cortex, parac- , medulla.
Spleen – large organ, like a node. Filters antigens. Removes old blood cells. Red and white pulp.
MALT – lymphoid cells, not highly structured. PP and tonsils are types of MALT.
Tonsils – accumulations of nodes.

Chapter 12 - The Humoral Immune Response

1. Define the following terms: antibody, antigen, epitope, monoclonal antibody, T-independent antigens, and T-dependent antigens.
Antibody - protein made by B cells that has affinity and specificity for antigens of pathogens.
Antigen – particle that our immune system recognizes as non-self
Epitope – specific part of the antigen that the antibody recognizes
Monoclonal antibody – antibodies produced by the same B cell, and which therefore all have the same specificity.
T-independent antigens – antigens that do not require T cell involvement to fight. They have a large and repetitive structure (eg flagella) that B cells can recognize and have several membrane-bound antibodies bind to. This activates the B cell to produce antibodies, though it is not a full response – they only produce IgM and no memory cells are produced. Class switching requires the TH cell activation.
T-independent antigens – antigens that need the help from TH cells to activate the B cells. Both T and B cells need to be stimulated. Usually proteins, and create memory cells.

2. Describe the structure of an antibody. List and give the principle site of action and principle biologic effect for the 5 different classes of antibody (see Table 12-1).
Antibodies are made of four chains help together by disulfide bonds. There are 2 heavy and 2 light chains. The light chains run parallel to the heavy chains, and the molecule as a whole makes a Y shape. The tip of the Y arms is the location of antigen binding, and the other end, the Fc portion, interacts with immune system cells. The light chain is variable through changes in V and J, and the heavy chain, through V, J and D. The 5 classes are IgM (first to the infection site, a pentamer, can be membrane bound to B cells, and v. good at agglutination), IgD (membrane-bound, B cell activation), IgG (most common, can cross placenta, longest life span, secondary response, opsinization), IgE (anaphylactic response, interacts with MAST cells), and IgA (in secretions, a dimer). M and G are used to activate the complement system.

3. Describe how a B-cell is activated to secrete large amounts of antibody (also called clonal expansion). What is a secondary antibody response? How is it generated?
The B cell is activated by interaction with the antigen and activation by a TH cell. This causes differentiation and proliferation – antibody production via plasma cells. 2ary response is when memory cells are activated and diff and prol. again

4. What is complement? Describe how complement is activated (both the alternate and classical pathways). What does activated complement do?
Complement cascade – starts w/ Ig and C1.in classical pathway. Leads to MAC formation and inflammatory response (vaso perm and vaso dil. By C3a and C5a – activate histamine which causes dilation and perm.), and opsinization. Alternate pathway and lectin pathways can also activate it. Regulated by C1 inhibitor and C4 inhibitor.

Chapter 13 - Cellular Immune Responses

1. Describe how Natural Killer (NK) cells function to destroy virus-infected and tumor cells.
CD8 cells interact with cells expressing antigen on MHC I receptors. The CD8 cell must also be co-activated by a CD4 cell by the CD4 cell binding to an MHCII receptor. The CD4 cell releases cytokines to activate the CD8 cell. The activated CD8 cell proliferates and differentiates into patrol cells and some memory cells. The patrol cells are activated when presented with another MHC I receptor with the same antigen. It releases vesicles of perforin and leaves. The perforin moves to the infected cell and inserts itself into the membrane in rings, causing holes in the membrane, leading to cell lysis.

2. Describe antigen presentation to T-cells and their subsequent activation. Be sure to include the activities of the CD4 or CD8 molecules as well as the MHC (HLA) molecules.
TH (CD4) cells are activated by antigen presentation on MHC class II molecules. MHC II is expressed on antigen-presenting cells such as macrophages, dendritic cells, and B cells (though this is a special case). Once activated, the CD4 cells act as helpers to activate B cells and CD8 cells as a co-activator with the antigen. CD8 cells are activated when they interact with antigen presented on MHC I receptors. This is the primary signal. All nucleated cells have MHC I. The second activator signal for the CD89 cell comes from a CD4 cell that has been activated by MHC II. It releases cytokines that activate the TC cell, leading to it’s proliferation and differentiation (patrol cells and memory cells).

Chapter 14 - Immune Responses to Infectious Agents

1. Describe the organization of our defense systems (the 3 layers/walls of defense against pathogens and toxins). Be sure to include each of the following components and their functions: barriers, innate responses, acute inflammation, complement, interferon, fever, and Ag-specific responses.
1st wall – barriers. This includes the skin, mucous membranes, and secretions (lactic acid, fatty acids, tears, mucus, lysosyme, acid). Barriers keep the pathogens from ever getting in to the tissues they would infect.
2nd wall – innate response. Non-specific defense from immune system cells such as macrophages and natural killer cells. The inflammatory response is part of this, and it can be mediated by the complement system and cytokines. Interferon helps defend against viral-infected cells as it helps neighboring cells prevent infection. The fever response raises the body temperature which helps B and T cell proliferation.
3rd wall – specific response. Takes some time to mount (5-7 days). Based on antibody interactions in B cells and activation of CD 8 cells. IgM is the first to the scene, and helps especially with agglutination of the antigens. Igs also neutralize the pathogen and toxins, opsinize the pathogen for phagocytosis, and activate the complement system (leading to MAC formations, inflammatory and fever responses, further opsinization). IgG is the second main type produced in the first exposure, and the main type produced in a secondary exposure to the antigen.

2. Define/describe the following: diapedesis, chemotactic factors, exogenous pyrogens, and endogenous pyrogens.
Diapedesis – immune cells moving through the capillary, especially once the inflammatory response has been initiated (heat, redness, oedema, pain) via increased vasopermeability and vasodilation.
Chemotactic factors are parts of the complement system and that attract macrophages and neutrophils to the site of the infection.
Exogenous pyrogens are fever-inducers that come from a pathogen that is infected the body (eg.toxins, LPS).
Endogenous pathogens are fever-inducers that come from within your body (cytokines).

3. What do the following terms mean in relation to the Ag-specific responses: specificity and memory?
Specificity means that each antibody will interact with only one antigen (or, more specifically, one epitope on that antigen. It will not interact with other antigens. Memory refers to the differentiation and proliferation of memory cells. These cells remain in the body for years after initial exposure to the antigen and are activated upon a second exposure. They are able to proliferate immediately, decreasing the time for the second immune response.

4. What types of Ag are B-cells effective against? What types of Ag are Cytotoxic T-cells effective against?
B cells are effective against pathogens that remain outside the cells such as bacteria, toxins, and multicellular parasites. CD8 cells are effective against intracellular parasites such a viruses and some bacteria. They are also useful against some non-infectious diseases such as cancer.

5. Describe the activation of B-cells and T-cells (in the depth covered in class). What role do helper T-cells play?
B cells are activated when the membrane-bound IgD or IgM on the B cell comes in contact with the antigen. This is the first activation signal. The B cell takes in the antigen and presents it using MHC II. A CD4 cell comes and binds to the MHC II receptor coupled with the antigen and completes the activation of the B cell. Once activated, the B cell proliferates and differentiates, producing plasma cells (antibody factories, can produce 2-3000 antibodies per second, but live for only 24 hours) and memory cells (stay in the body for years, ready to mount another defense against the pathogen).
TH cells are activated when the bind to MHC II receptors with antigen presented on APC cells. After activation, they help with activation of B and TC cells.
TC cells are activated when they bind to an MHC I complex (first signal). A TH cell then comes and, once activated by MHC II presentation, releases cytokines to activate the TC cell (2nd signal). The TC cell then proliferates and differentiates into patrol cells and memory cells.

6. How do B-cells respond to protein Ag? How does that differ from carbohydrate Ag?
Proteins give a stronger response than carbohydrates.

7. List and describe the functions for Ab.
Agglutination – contains the pathogens. Easier to phagocytose.
Neutralization of pathogens and toxins
Opsinization – phagocytosis
Complement activation- C1 binds to Ig.

8. Describe the differences in the primary and secondary responses to an Ag.
1ary – first exposure. Slower response. Has to activate all cells. IgM high.Makes memory cells.
2ary – subsequent exposures. Fast response. Cells already useful. Much greater level of Ig produces. More IgG than IgM. Uses memory cells.

9. What does an immunization do? What are vaccines made of?
Gives the immune system a 1st exposure w/o causing illness. Several types – attenuated whole (full cell, weakened chemically), inactive (dead), conjugated (w/ adjuvant to increase immune response), toxoid (inactive toxin used to create Igs against toxin – esp. for Clostridium spp.), recombinant – part of the cell)eg. Just the antigens) are made in the lab using yeast w/ the gene inserted. Good for bacts. that do not culture well).

10. What are allergies? How do they occur?
Abnormal immune response to a non-pathogenic antigen. Uses IgE and MAST cells to release histamine in response to the antigen. Response too great. Leads to dilation and perm, which can be systemic (bad – anaphylactic shock – decrease in BP). Histamine also causes runny nose and sneezing. Athsma – hist. released in the lungs. Can be decreased w/ allergy shots – use the antigen to teach the body to respond w. IgG and IgA instead.

11. What is autoimmunity?
Immune cells interpret self cells and non-self cells. Immune response is initiated for self-tissues. Normal proteins are seen as not normal.

12. Describe why transplanted tissues and organs are commonly rejected by the host.
The transplant tissues have proteins on them that are not “self”, so they immune cells attack them.

Untitled 3, 2009.

So, my test went well. It was one of those tests that doesn't tax you mentally so much as physically - I had to take a few breaks just to give my hand a rest before plunging in to another long-answer question. I spent the night at my friend Katie's house, which was great, and my brain woke me up at 6:30. Just the way I like it. I've realized this semester that when I give myself adequate amounts of sleep, I feel better and concentrate better. How weird is that? There may be something to this... but really, I haven't had to have ANY all-nighters this semester. Which for me, is amazing.I'm usually up at all hours of the night working away on things, secretly wanting to cry because I was so tired (my roommates Whitney told me once that she was impressed that I had the discipline to stay up and get things done even when I was exhausted. I told her that I was impressed she never had to :) ). Anyway, so I woke up early and got to reading around 7:00, which was just perfect. It was a quiet morning, I just sat at the kitchen table reading away (and completing a 9-page study guide... maybe I'll post it here for fun... ha.). It was just so nice. And I feel like an expert on T-cell activation now. So that's good.

My friend Romy had a cool idea on her blog - she wanted to do a little tribute to members of her family throughout the year, and decided to do it on their respective birthdays. Genius! So I've decided to follow suit, and also include some great friends who are practically family too. For those who are familiar with my blogging habits, you know that it may turn out to be a sporadic effort, and that you may be lucky to be written about in your birth month, or season, rather than the actual day. Still, I'm going to try. Since I'm a little behind (two months gone already!), I'll have to catch up a bit...

I'll start with my brother Matt (his birthday is in February, so it's a good thing I'm getting this done today!).

So first I have to apologize that I don't have any great pictures of him. His wedding pictures are really nice, but... they're not on my computer. On the other hand, a picture of him eating a ginormous turkey sandwich is a lot more like what you'd see day-to-day of him rather than a picture of him in a tux.

Anyway. Matt is pretty cool. He lives in Calgary and plays with maps all day (at least that's what I think he does. I could be very wrong). We weren't exactly best friends growing up, but I really appreciate him now (I guess that's how life goes). He's really good at doing little things that mean a lot. One day at school I was having a hard time balancing everything, and he called Domino's pizza in Rexburg and had a pizza delivered to me. It was awesome, and completely unexpected. I like being able to talk to him every now and again and hear about his experiences. I can usually get some advice out of him too, which is great. :)

Friday, February 27, 2009

Untitled 2, 2009.

I suppose there are times when one just needs to vent a little. This is one of them. I think my thought might come out a little jumbled, but they have been rolling around in my head for a while, and so they probably got out of order in the process, much like socks losing their partners in the dryer (on a complete side note, I did laundry last night and as I was putting away my socks, I only found ONE of one of my most comfy pairs (yes, mom, it's the moose socks you gave me for Christmas :) ). I got down to the bottom of the hamper, and - still only one moose sock. The thought of having lost the sock was nearly as bad as the thought to go back to the laundry room and look for it (hey, it was cold and I was tired). I picked up my sweatshirt that had been in the laundry and shook it. No sock fell out. I picked up my freshly-cleaned towel and shook it, too. No sock. I shook it again (for good measure), and... SOCK! I was very happy. So were the moose, I imagine). Ok, that was an unusually lengthy side note. Onward.

The situation at the present time is that two of my 5 roommates are likely to be kicked out of school. And while part of me feels sad for their situation (it is a strict punishment), part of me can't even try to feel sorry for them. They have been messing up all semester and have been given warnings, but ignored them. Now they are getting the consequences, and suddenly it's all "unfair". I was at home for a couple hours today and all I (over)heard was conversation about how angry they were with our Bishop (for those unfamiliar, the Bishop at school has the authority to make these types of decisions, after counseling with the Dean of Students), how they are going to "get back" at him, and how stupid the whole thing is. It was sickening.
I'm not quite sure what to do about things, and I realize that there may not be anything I can or even should do. I guess I'm just trying to deal with it and not let it bother me. But it really does. It's hard to describe all that I have been feeling about this (and other things like it) this semester, and in a way it's been a real eye-opener. I have never met people like this before (I have left a lot of things out... partly out of laziness, partly because I think that writing it all down would only make me feel angry again), and have been learning a lot. One thing I have noticed is that parents' attitudes really do rub off on children. And I am even more grateful for my parents! They are people I can be proud of, who try their best to do the right thing and to live their lives based on principles of kindness and respect. They are very selfless and care about others. I am so glad that I have been able to learn from them. I don't think my roommates have very good relationships with their parents, or their parents never bothered to teach them about respect and honesty (or, a third option, their parents did teach them all this and they were just brats about it). It's so sad.

I think one thing that just gets to me is their attitude of deserving everything without having to work for it, and not appreciating the work that others do for them. They don't understand principles of gratitude or humility. A quotation (don't ask me who said it first) comes to mind: Don't expect the world to give you everything. The world owes you nothing; it was here first. I know that I haven't always been the most grateful person, and some of the experiences that I have had over the past year or so have really gotten it into my head that nothing can be taken for granted. Every day that we have good health, we should be glad for that. Every meal we are able to have, we should be glad for that. So many people have much less. I learned an interesting statistic this semester - about 73% of our tuition is paid for by tithing of the church (meaning, the amount that I stress about having to pay every semester is only about 27% of the actual cost of my education). That is a whole lot of money being paid by people I have never even met. And I think that we owe it to the members of the church to treat our educations with respect.

Anyway, I think I have exhausted today's frustrations, and I'm doubtful of my ability to even try to add in another jumbled thought.

Plus, I should really be studying for a test right now.

Tuesday, January 20, 2009

Untitled, 2009.

So, I was recently informed (and by "recently", I mean approximately 2 weeks ago) that my parents have been pretty awesome for a while now. Which is true. But it was meant as a subtle (sort of) hint and reminder that I haven't exactly updated my blog in a long time. So... here goes. I'm all rusty though. Might not have any witty remarks until next time.

I'm taking a ceramics class this semester (just for fun), and I'm enjoying it, though I'm definitely at the shallow end of the artistic talent pool in that class. There are a lot of amazingly creative people there, it's fun to see each other's work and style. We had our first assignment this week - we had to make a piece using coils (which is a fancy artist term for "rolled-out snakes"). Here is mine:



It's about 12 inches across. I suppose it will be good for holding fruit... or socks... or maybe a LOT of jelly beans! :) I took the picture with my phone, so it's not the best quality, but you can see what I made... you can also see a bit of Josh's castle and Maiko's sculpture.