Saturday, January 29, 2011

Action Potentials!

Hooray for a post with actual substance!

So here is a great picture of a typical neuron cell. This is taken from, a fantastic website with very clear diagrams.

So let's talk a bit about the morphology of this cell a bit. What we have is a normal cell that has a bit of an unusual shape and some specific changes that allow it to have a bit of a different function.

The cell body in this picture is the main portion of the cell, with the nucleus and all of the typical cellular machinery: mitochondria, rough endoplasmic reticulum, ribosomes, smooth endoplasmic reticulum, golgi apparati, and so forth according to the function of the cell.

It also has little processes that come off of the cell body called dendrites. These processes allow for signals that come in from other cells. Dendrites are how a cell receives information. Depending on the type of cell, these processes can either be concurrent with other cells, i.e. their cytoplasm is continuous from cell to cell, or there is a gap between cells called a synapse. Both are means by which signals are sent from cell to cell. We will come back to this concept.

See that long big process coming off of the cell body? That's an axon. Signals that are received from the dendrites travel down these axons and hit the axon terminals, which connect to dendrites or cell bodies of other cells depending on whether they are an electrical synapse (or continuous) or a chemical synapse (gap between cells).

Imagine you have a balloon filled with and submerged in water. The water inside the balloon has a different mix of stuff than the water outside the balloon. The stuff that we are talking about here are ions, or atoms with charge. If you aren't sure what an ion is, here is a clear article on the topic by Wikipedia.

Since the mixture of ions is different inside than outside, it is called a gradient. There are two different types of gradients: electrical, based on the overall charge of the mixture, and chemical, based on the overall concentration of the mixture.

Imagine that the balloon has little holes that allow the ions to move. The little holes can just stay open to let the ions move freely, or they can be regulated to only allow the ions to move at certain times. These holes are called channels. The ones that stay open all the time are called leak channels. They allow for small amounts of movement in and out of the cell. There are many types of channels that are regulated, but the ones we will concern ourselves with are channels that mainly allow only one type of ion through at different times, and pumps. Pumps allow for exchange of ions between the inside and the outside and depend on actual energy to operate. The best known is the sodium/potassium/ATPase pump, which burns the currency of metabolic energy, ATP, in order to exchange sodium (hereafter referred to by its atomic ion symbol, Na+) and potassium (K+) between the inside and the outside.

Our balloon analogy can only go so far here, so let's replace in our minds the balloon with a cell. The walls of the balloon are the walls of the cell, called a membrane. The channels are proteins that are embedded in the membrane and allow for passage of ions. The pump is a channel but it has a very specific purpose. The fluid inside of the cell is called the intracellular fluid (ICF) and the fluid outside is the extracellular fluid (ECF). This will become important later.

So bear in mind that leak channels allow ions through freely, but that there are many of these pumps that maintain concentration gradients. The question, of course, is what effect these pumps have on maintaining the electrical gradient.

Stay tuned for the next installment, where I will talk about setting up electrical gradients and how the membrane has a resting potential. I anticipate there being a part three that discusses what an action potential is and why they are important.


Friday, January 28, 2011

Return Of The Applications

Hello dear readers! I know I've been quiet lately, but what with hurting my ribs and grad school applications, I've been swamped. Couple that with a job hunt and school starting, and I do hope you can forgive me my silence.

BUT! I'm coming back with a vengeance, after I rant slightly about the application process.

So this is my own damned fault, frankly, but I forgot about deadlines for a program that I REALLY want to get into. It's close to home, I already know a ton of the faculty, and I'm already attending school there, albeit informally. So I scrambled and scrambled, and I'm getting everything together.

Here is what I hate about applications: they make you list your classes and grades ad nauseum for each program that you apply to. I don't think I realized how lucky I was with the AMCAS, because I had one application, one set of credentials to list, and one essay to write. Instead I have to write a statement that conforms to each programs' specifications, fill out two applications per program, and list my classes and grades according to each program's idiosyncratic application criteria. Exceptionally time consuming.

It was pointed out to me that they make students spend the time so that people who process applications don't have to; otherwise app fees would be astronomical and it would take forever to reach a decision because they'd have to pay people to do all of the busy work that I'm currently doing. It made me a little less bitchy, but only just. ;)

So grad school. I'm applying for master's programs or alternatively a series of classes that will hopefully make my med school applications look more competitive. I only have 4 of 16 med school applications still outstanding; the rest have declined to interview me. It is looking a bit grim, so I need backup plans. I have been told that I shouldn't take it personally, and I don't. I realize it is part of the process and that while I have lots of qualifications and experiences, my grades could be better and my MCAT scores stronger. Because of the economy, cutbacks in faculty hours and facilities, a lot of med schools are tightening their criteria. Makes a process that is really tough that much more difficult to get through successfully.

Plus my cellular neurophysiology class last semester was taught by two post docs, and both actively do research. One is a neurochemist who studies neurotransmitters, and the other looks into how the brain changes with drug dependency and did her thesis on how alcohol addiction changes the brain. Her model organism? Rats. Yes, she got rats drunk and looked to see how their brains changed over time. It's pretty frickin' awesome.

And they really got me excited and enthused about doing some research. I've been doing my research internship at SFGH, and I really have been enjoying that. I have read anecdotes about a couple of students who were accepted to medical school and decided not to because research was much more appealing to them. I realized that I don't know much about research, and that given where I am in my life, perhaps I should give it a fair try. Who knows, I may end up as a PhD and studying plasticity in drunk rats. It sounds like a great career to me.

So I'm applying to two MS programs and an MA program. I also applied to two programs that are not degree programs but would give me a stronger med school application next time around. I'm not sure how much I want to actually spend two years and not get a degree of some sort, but we'll see how this goes. One program is in New York, which is slightly scary. I don't know if I want to leave my husband for a year while I go do this program and then possibly go to another state that is not home to get my medical degree.

Perhaps you are getting a sense of what I'm up against. There are a number of variables in my life. Nothing is certain and everything seems convoluted. It is a bit scary because I don't know where my life is going, but it is also exciting. I have a number of opportunities available to me.

So I have all of my letters of recommendation lined up (easy! my advisors are the best and are so nice, even though I didn't give them as much time as I wanted to) the transcripts and exam scores are all ordered and sent, and my goal these next two days are to finish ALL of the applications and statements.

I also have a tentative offer to join a neurodevelopment lab at one school. I'm holding out for my first choice, but nothing will be decided or agreed upon until after applications are in anyway. Thankfully MS applications are NOT on a rolling basis like med school apps, so no movement is done on processing until after the deadline is passed. This is more of a benefit than it seems, because it gives me time to sort out things like which lab I can work in and thoughts about a project.

I am taking a pharmacology class and a systemic neurophysiology class this semester, so I will have lots of fun material to talk about. I really wanted to post a bit about action potentials and graded potentials, because they are the basis for everything that our brains do.

Till then, ciao!

Friday, January 21, 2011

Science =/= Religion

I will say this again, for anyone who is listening: SCIENCE IS NOT A RELIGION.

I HATE having this conversation over and over and over. Argh.

Tuesday, January 18, 2011

I Asked, And You Answered!

Because I was curious about how other people view the debate, I went around to a bunch of fantastic blogs that I follow and I asked the same question:

What is your opinion on the use of ridicule in a debate between a theist and an atheist? I know some people that say it's divisive and that it serves no purpose other than to drive a deeper wedge between groups. Can you talk about how you think it might be an effective tool when trying to change someone's mind about their belief?

In Reason,
-Reading Frame

And boy, did you guys come up with some great answers

Hateful Atheist just posted the response, and as always the explanation was well worded and thought out.

Bible Belt Atheist had a response so good that other folks reposted his response.

And in a slight detraction from the rest, Underground Skeptic thinks that ridicule is divisive and serves no purpose.

My personal opinion is that it is important to differentiate between an idea and the person having that idea. Certain ideas are incredibly asinine and deserve ridicule. The difficulty lies with the fact that many, if not all, religious people perceive themselves as being indistinguishable from their belief, and so attacking their ideas sounds like a personal affront.

Satire seems like a great way to shock people into thinking harder about their belief, and we know that the Flying Spaghetti Monster is a magnificent piece of satire designed to show that intelligent design is really creationism dressed up in flowery pseudoscientific language.

It is also important to know your audience. Are you debating a theist because you really think you will change their mind, or are you doing it to defend your own beliefs, or are you doing it for someone else's benefit? It is a tactical considration that you must make, and it can go horribly wrong if you misjudge your audience.

Their responses have given me a lot of food for thought. Much obliged, gentlemen, for your time.

Stay Reasonable,

Sunday, January 9, 2011

Death For Blasphemy

A governor in Punjab, Salmaan Taseer, was murdered by his bodyguard, an unstable man by the name of Malik Mumtaz Qadir, after working to reform blasphemy laws.

Blasphemy laws. A law that says that blasphemy is punishable by death.

From Wikipedia, a concise definition of what, specifically, is blasphemy: defiling a Quran, defaming Muhammed, or generally saying just about anything that mocks or questions someone's faith.

This is beyond absurd, beyond monstrous, beyond barbaric. People are being thrown into prison for criticizing a violent religion that seeks to quiet dissent, by threats, murder, and intimidation, and some poor governor has now paid the ultimate price.

The person who murdered him, and openly confessed the crime, has been offered all kinds of legal support, and was awash in kisses and rose petals when he appeared in court.

Do these people have the most incredibly fucked up list of priorities ever, or is it just me? He KILLED SOMEONE, for working toward making the law a bit less harsh to people who criticized their violent  religion or ripped up a book full of outmoded, antiquated, evil ideas. Not only do the people of Pakistan think that someone should die for that, but they are practically venerating the man who performed the deed.

Where are you, moderates? Why are there no loud voices saying that this is not Islam, violence isn't the way of our religion, we really aren't like that? Where are the people stubbornly insisting that Islam is a religion of peace? Why am I only hearing crickets?

If Islam is a religion of peace, then why does it open the door for things like this to happen? Why is it as a collective body actively trying to squash dissent and criticism to the point where people must fear for their lives?

What happened to Pakistan? It is seriously devolving into something that Muhammed, were he alive today, would be very proud of. And that is terrifying.

Let me break it down for you, in case the point has yet to be made clear: 900 years ago this behavior by your savior wasn't exactly appropriate, and it certainly isn't today. There is no excuse for this barbarism. I would have thought that most people would have grown past this, and now here you are, proving my optimism for the human race wrong yet again. This is a plague of mental illness that is sweeping the Middle East, and unfortunately a lot more people will have to die for this lunacy before people realize that killing someone over a book probably isn't the best way to treat your neighbor.

People who openly criticize the religion and the things done in the religion's name are having to go into hiding or are being killed. Atheist Oasis has a brief list, but unfortunately these are just the high-profile cases.

What can be done before this is brought to a halt? It seems like it would take a major social revolution to make that happen, if the thousands upon thousands of people that hit the streets after the governor was murdered are any indication. It was obviously a popular move. Butterflies and Wheels has a a statement made by the deceased man's son, expressing with clarity his sorrow over a Pakistan slipping away into theocracy.

In Reason,

Thursday, January 6, 2011

IRS vs. Medical Residents

In November, the Supreme Court essentially said that the IRS can categorize medical residents similarly to apprentice tradespeople or law clerks, due to an overall reluctance to overturn an arbitrary rule that medical residents must pay Social Security taxes.

But medical residents are students. They get paid a pittance so that they can survive while going to school. That pittance is essentially compensation for the egregious number of hours that the teaching hospital requires them to put in while receiving training for their job. states that in exchange for a list of required tasks to complete at the hospital (remember, 80 hours a week in 16 hour shifts) most residents make approximately $35,000 a year with increases of about $1500 a year until completion or fellowship.

A side note: where did Justice Sotamayor get the $50,000 a year figure? Most sources I have checked say anywhere from $35-40 K a year for most residents at most teaching hospitals.

In most areas of the country, that is barely enough to survive. Throw in the fact that the laws regarding loan repayments have recently changed, and thus the number of students that qualify for deferments/forbearance/grace from their creditors has gone down, and you have some desperately poor medical residents.

You want to tax doctors? Fine, do just that. I think that the rich should have to pay more in taxes anyway, because they can afford to. But while residents may have their MD, they are not full-fledged doctors yet, and thus aren't making that six figure salary. We are facing a critical shortage of doctors in this country, and the federal government certainly isn't making life any easier for the people that are trying to get out there and help the sick and the ailing.

I do sympathize with the idea that Social Security taxes are a big source of revenue. I get that. But right now the rules are exceptionally arbitrary. We need to ease up on residents and clearly define the difference between people who work to get to school and educate themselves and people who work to support themselves.

Wednesday, January 5, 2011

Mock Indignation Post

This was going to be my next post of substance: a bit of irritation aimed at the American Medical Student Association for buying into the Complementary and Alternative Medicine (CAM) crap....

But then I found this. *shakes fist angrily* Damn you Orac for stealing my thunder. ;)

He pretty much covers everything that I wanted to talk about, as well as links to previous articles that he has written.

My problem with this whole snafu is that students that don't know a whole lot about quackery might well get sucked into this stuff because of the verbiage involved. "Holistic, huh? That sounds good..." "Everyone knows you have to take your vitamins!"

They don't realize that such things are essentially scams, and that they are being suckered into a modality that has no scientific basis whatsoever. Even more disturbing is the idea that these people graduate from medical school thinking they are helping their patients when they are simply peddling woo.

I was disgusted to find that California Pacific Medical Center, right around the corner from where I live in San Francisco, has an "Integrative Health Center".

Codename for bullshit.

Sunday, January 2, 2011


I promised you content... and here is the first of many, I hope.

Recently there was a kerfuffle over allowing medical residents to work shorter hours. In the end, the law remained the same such that residents are only permitted to work 80 hours a week; the major change was that the shifts went from 30+ hours to about 16, though senior residents can do 28 hour shifts with "strategic napping".

This would seem to be painfully obvious to anyone halfway paying attention: tired doctors don't necessarily make the best calls for a patient that needs and deserves excellent care. Especially if the tired doctor in question is, in fact, in training.

With good reason, there has been public outrage about the number of hospital-associated mistakes. Unfortunately, the bandwagon has been made available to sensationalist media coverage of the number of times that people at hospitals screw up. It seems as if the culture that loves to find fault with an educated elite absolutely adored punching holes in the godlike facade of doctors. People like Faux news seemed to take childlike glee in exposing the idea that yes, doctors are people too. Yes, doctors are not infallible. Mistakes are made, and it is a shame, but the best that humans can do is to try an minimize the potential for such mistakes.

Now mind you, there are all kinds of systems in place to minimize mistakes. Nurses ask for I.D. and papers before drawing blood or doing any kind of procedure, due to a mishap at Mt. Sinai in New York with a woman going in for the wrong surgery. It is awful and deeply regrettable, and so we learn from these mistakes. We ask for I.D., discuss the patient's understanding of the upcoming procedure, answer questions, and try to have redundancy programs where if one nurse or doctor misses something, then someone else might be able to catch it. Much of the wait and drag of a hospital can involve running these types of checks. Yes it can get bogged down in bureaucracy, but I would rather have accuracy than speed when it comes to my health. 

Which is why I simply did not understand the hue and cry raised about lowering the number of hours that residents can work. Exhausted students that work 30+ hour shifts, go home to study more, and then must return to the hospital for more work simply makes no sense to me whatsoever if a patient's life is on the line.

Put simply, safety is put into jeopardy. I don't really see that as being an option, really.

Arguments against cutting back hours and shifts are kind of ridiculous, in my opinion. The one good argument against cutting hours was made by Orac a few weeks back, and it is somewhat compelling. We'll visit it by and by.

A residency is a paid apprenticeship. A resident gets paid very low wages for a lot of work, but it is expected because the resident is learning their profession and their craft. An attending doctor oversees their work and makes sure that they are learning what they need to learn, but in a lot of ways they are basically practicing medicine.

Because the resident is working for very low pay, certainly less than she can command as a full doctor, she pumps a lot of free work into the hospital. More patients can be seen quicker because there is a larger staff of doctors that can cover the demand, and thus the hospital brings in more revenue. The hospital benefits from this, much like when you volunteer somewhere. You are performing a service for free because it helps the organization you are working for, and you personally are possibly learning or devoted to a cause. The teaching hospitals objected to the proposed changes because it would cost them revenue.

My question to them is this: if it meant fewer mistakes, fewer lawsuits, and lower malpractice insurance, wouldn't you do it? I'd love to see numbers where the cost/benefit analysis was done, with an estimation of how much the hospital can save in lawsuits and/or eating the costs associated with mistakes, vs. how much revenue is lost from either requiring more residents to cover the lost shifts or not having that many residents.

The next objection was safety. I worked veterinary emergency for years, and I know what happens when shifts change. You hand patients off to the next oncoming shift. In many cases, to promote safety and make sure that things go well, you have the shifts overlap significantly (by perhaps 2 hours) to make sure that nothing comes up. The oncoming shift reads the chart thoroughly to make sure that they understand the case and ask questions to make sure that they get it.

The process takes perhaps 20 minutes TOPS. WHY is this so difficult for human doctors to do? What, precisely, is wrong with handing patients off to another doctor?

There was all of this noise made about "continuity of care" nonsense that really irked me. I've sen it done. It isn't that hard. Why is this kind of continuity so flippin' important that it was raised as a major safety objection? If there is something here that I've missed, please let me know, because I frankly don't get it.

Dr. Wachter's article above made some good points, which kind of coincide with Orac's argument. One is the idea that even though a shift is technically over and the resident is free to go, that the resident might need to stay for whatever reason. I do get this. I've done it myself, because I had a project or issue in the back of my mind that I had to handle before I left, and explaining it might be too complicated or take too long. This I do understand.

The other is the "swinging door" mentality, that the resident might be too eager to leave or know that the shift is over and that things might get dropped just because the resident knows they have to go. Appropriate care to detail and discussions with the attending or oncoming attending physician, in conjunction with staying to make certain that cases are being handled adequately or to handle the case yourself, can probably settle this issue. Knowing the kind of sacrifice, hard work, and discipline involved in getting into and graduating from medical school, I think that this concern really doesn't give residents enough credit for being mature adults. Communication is the key when it comes to patient care, and not being communicative enough with your team will raise all kinds of problems, not just this one.

And we come, finally, to Orac's objection, the one that I think carries the most water. There is a massive amount of information necessary to becoming a doctor, and a good one at that. Book learning can only take you so far, which is why there are residencies and internships. Residencies can be anywhere from 2-5 years long, because there is so much to learn. Orac's problem with decreasing shifts is that there is less actual time to learn what you must in order to pass the boards and be a fully accredited and independent doctor.

I understand and agree with this point of view: there is a huge amount of material to learn, and less and less time in which to learn it. There will be a critical point, with short shifts and a very long residency, past which students will be unwilling to devote their education to a particular discipline simply because of the time involved.  I also think, however, that there are ways to increase the efficiency of a program so that you can indeed learn more effectively. Due to the shift restrictions, this conversation about restructuring the residency programs offered at teaching hospitals is already happening. I think that that is a great idea, because learning medicine is like trying to hit a moving target: it is constantly changing and updating itself.

There are good objections to changing the shift requirements and allowances for residents, but I honestly think that the most important ones are being lost in the shuffle. In addition, creative solutions to solving the aforementioned objections are also being lost because of a seemingly stubborn adherence to a fixed curriculum.

Saturday, January 1, 2011

A Post Worth Keeping

I saw this on I H8 Religion, and it made me so happy. I want to keep this.

A Happy New Year Wish

Happy New Year, all,