Wednesday, May 30, 2007

My Brain is Full

I'm more behind than I usually am for the upcoming test. As a result, I'm going to take a short break from blogging until Monday. The midterm covers a pretty diverse range of topics: neurology (MS, epilepsy, stroke), fuzzy stuff (behavior, memory, language), and psychiatry (depression, bipolar disease, suicide).

Interestingly, today I went to a talk by Robert Sapolsky. I had several classes with Sapolsky at Stanford, and he's a fascinating guy. His lecture style is a storytelling manner where he can really bring out the scientific debates and controversies underlying neuroscience, behavior, and psychology. He has a remarkable familiarity with different studies and papers and can make cogent arguments defending his positions. His primary research is on stress hormones; he also collaborates with baboons in Africa so much that a TA suggested he started looking like one. His talk today was on the biology of depression and covered neurochemistry, anatomy, endocrine, and psychological factors.

Tuesday, May 29, 2007

Preceptors and Apprentices

We recently had our last preceptorship for this year. Despite the clinic being in Oakland, I really enjoyed my preceptorship. I learned a whole lot about working with patients, especially older patients. I've gotten better not only at gathering information in an interview and doing exams, but also at how to act like a doctor: how to observe things, to pursue important details, to control the flow of the conversation. I'm a bit sad to leave the patients, many of whom I've seen multiple times. My preceptor was also pretty good at teaching me about outpatient medicine and giving me lots of independence to learn.

Today, we had a psychiatry apprenticeship. In small groups under guidance of a psychologist, we interview patients with a wide range of disorders from bipolar disease to depression to suicide ideation. I've learned to gather a lot of data from just talking to patients and watching them as part of the mental status exam. I have a lot of sympathy for these patients, but sometimes I wonder how important it is to "be nice." In some cases such as low self-esteem or severe depression, encouragement and sympathy is important for the patient's well-being. But do we lose objectivity if we become emotional? I'm not sure. I know that building rapport, trust, and understanding is key to any patient-provider encounter, but I don't want to lose objectivity by getting too affected.

Monday, May 28, 2007

Catching Up

This upcoming exam has a random smattering of subjects. Some of the interesting ones are sensory organs; though in the past, I never really liked studying vision, hearing, and balance, it's actually quite amazing to think about how perfectly "designed" these structures are. It's also amusing to me that in the eye lectures, the professor showed a number of optic illusions and we were all amazed. The less interesting subjects for me are pharmacology and histology-pathology. We're starting to get bombarded with a lot of drugs whose names have no rhyme or reason (now I start to miss the -lol beta blockers and -pril ACE inhibitors). Some drugs are interesting because they've made it into pop culture (Prozac, Valium), but it's still a lot of memorization. Histology-pathology for BMB is a little different than in the past. Everything is taught in small groups with projected slides rather than specimens and microscopes. I miss seeing the actual pathology specimens; those are kind of cool. And though it's nice to have labeled slides, I also miss the independence of working the microscopes.

Sunday, May 27, 2007


Today's post is completely unrelated to medicine and UCSF. On the first day of a poetry creative writing class I took as an undergrad, the instructor asked if anyone could recite a poem. And although I have always found good poetry magically powerful, I never really committed a poem to heart. But one girl in the class was able to recite "Questions of Travel" by Elizabeth Bishop. That was breathtakingly impressive; it's a considerably long, complex, and beautiful poem. At that moment, I decided that I wanted to find and memorize a poem I really liked.

But what poem? I could take the traditional route and try a Shakespeare ("Sonnet 116" or "Sonnet 130"). There are parts of Alexander Pope's Essay on Criticism that are absolutely fantastic ("True ease in writing comes from art, not chance..."). But lately, I've become enamored with more modern and contemporary poets.

Ever since I heard Billy Collins, a previous U.S. poet laureate, speak at Stanford, I have become obsessed with his poetry. One of my friends describes him as "conversational whimsical" (or something like that) in that he is incredibly accessible yet surprisingly complex, humorous, and magical. I recommend the poems "Flock" and "The Lanyard" and "Thesaurus" among many. But I think when I get around to it, I might try memorizing one of my other favorite poems, Yeats' "No Second Troy."

All poems mentioned here should be google-able. If you're looking for more poems, I really like the Poetry 180 series sponsored by the Library of Congress.

Saturday, May 26, 2007


Both this weekend and last weekend, I went down to Stanford to see some of my friends' senior recitals, performances organized by Stanford's music department for graduating seniors. Last week, Tracy played a number of beautiful waltzes on the piano. Next year, Tracy will be in the UCSF dental class of 2011. With selections from older composers like Chopin and Debussy to contemporary pieces from The Waltz Project, it was a fantastic selection of music. This week, Doris (piano) and her friend Claire (violin) had a joint performance. In particular, I loved the Beethoven Sonata in A-flat Major, Op. 110 (Doris) - it has this amazingly dynamic range of sounds, moods, and themes. She also played an absolutely wonderful Transcendental Etude No. 9 ("Ricordanza") by Liszt. I really love the airy, graceful feel of that piece; the word transcendental really fits. My favorite violin pieces were a Tchaikovsky Concerto in D and a Sarasate ("Navarra"). The Tchaikovsky has a gorgeous theme, and the Sarasate is really fun since it's a violin duet. In any case, it was good to support friends who have spent so much time preparing. I miss classical music and wish I had more time to practice.

In other news, I spent a few hours in the neurosurgery operating rooms yesterday. During BMB, they have an awesome shadowing program for us to see different neurosurgeries. Yesterday, we saw a temporal lobectomy because of intractable seizures. It's amazing to see the precision and poise of the surgeons as they expose part of the brain, identify by EEG abnormal areas, and carefully cut it out before sewing the tissue and plating the bone back together. The surgeons, anesthesiologists, and residents were all very good at answering our questions and showing us interesting things.

I'm going to have to concede to studying for the rest of the weekend. Every time a test comes up, it feels like I'm playing chicken with the exam. How far dare I go before picking up the syllabus? Except in this kind of game of chicken, I'm always going to lose. So I tell myself soon, I'll start reading soon.

Friday, May 25, 2007

MedTeach Revisit

The first picture is the MedTeach team: Me, Sarah, Stephanie, and our two teachers at Alamo Elementary School. The second is me showing some 5th graders small intestine. We recently taught our last lesson on the brain. I had the usual anatomy specimens of a rat brain and a human brain; we also had really exciting stations on spinal cord signaling (how does your brain get information from your foot and then tell your foot what to do?), reflexes (with reflex hammers for all the students to practice with), and "drunk goggles" that impair coordination. It was a lot of fun; one of the classes made a really sweet "Thank You" book with pictures and descriptions of their favorite lessons. I'll miss working with the students and teachers, and I wish I could do it next year, but it doesn't work well with the second year schedule.

We also had a MedTeach banquet which was great. Everyone participating in the umbrella organization "Science and Education Partnership" was there. We spent the first bit writing up some feedback for the program and discussing our experiences. Then, they had quite a nice reception with waiters and waitresses carrying around platters of fancy-looking appetizers. That's always a good sign! Dinner was a sit-down three-course affair, quite different than our usual fare. I had an excellent time talking to the other first years who did MedTeach.

Thursday, May 24, 2007


Amyotrophic lateral sclerosis or Lou Gehrig's disease is a progressive, fatal neurodegenerative disease caused by loss of motor neurons. Eventually, motor weakness leads to atrophy, complete paralysis, and respiratory failure. There is little decline in mental function. There are no cures and few effective treatments. Most cases are sporadic.

Last Monday, BMB screened the documentary "So Much So Fast." It follows 5 years in the life of a 29-year-old who discovers he has ALS. It's a particularly poignant movie as you see how this plays into his life goals such as whether to have kids and how to keep building houses (which he loved to do). You can really see the impact of the disease on his life; at the beginning of the movie, he appears to be pretty normal, but within months, he has to use a walker, and then a wheelchair, and finally a computer-aided communication system as even the muscles for his vocal cords have failed. The documentary also describes the difficulty in convincing drug companies to conduct research in ALS because of a perceived lack of market. The brother of the victim in this movie creates a foundation of "renegade scientists" who take an interesting "shotgun screening" approach to find something to help ALS. It's quite a good documentary, educational and moving.

After that, we actually saw someone with ALS. In respect to the patient and his family - even though I'm fairly certain they would not mind - I won't go into much detail about this. However, it really struck me how debilitating and scary this disease is. The person was actually a neurologist who specialized in and did research on ALS. It's a sad irony that he found himself inflicted by the same disease his patients have. It really devastated me to see how terrible ALS is and the profound impact it has on family.

Tuesday, May 22, 2007

Mental Illness II

There were a few other things about mental illness that I learned. While it is not a significant contributor of mortality per se, it exerts a huge impact on disability adjusted life years - how many years of healthy life are lost. In fact, depression, alcohol dependence, and schizophrenia are responsible for 11% of disease burden worldwide. These problems are prevalent in third world countries. We also spent some time in small group discussing the stigma attached to mental illness. Like those with obesity, AIDS, and even cancer, there is a huge bias, distrust, fear, and stereotyping of patients with mental illness. This makes resources, job opportunities, etc. a lot harder to find. Indeed, a lot of people think that such diseases are a result of personal weakness: obesity is a lack of control over eating, and schizophrenia is a weak mind. This is just not the case. We should not characterize these people by their disease; we need to help them seek and get the care they need. Lastly, I was interested in the concept of a "5150." In the California Welfare and Institutions Code, any qualified officer or clinician can involuntarily confine a person who is a danger to himself, herself, or others for up to 72 hours in a mental health institution. This is fairly interesting; the state takes responsibility for an individual's well-being and can supersede that individual's autonomy, raising some ethical questions.

Monday, May 21, 2007


Things have been tumultuous lately. I'm trying to sort out my life. I have been somewhat neglecting this blog in the past few days, but I'm reminded of a poignant quote by Norman Mailer in The Spooky Art.

"Writing is wonderful when you talk about it. It's fun to contemplate. But writing as a daily physical activity is not agreeable. You put on weight, you strain your gut, you get gout and chiblains. You're alone, and every day you have to face a blank piece of paper."

Soon I'll get back on my feet and have my pen back on the paper.

Sunday, May 20, 2007


One Art
Elizabeth Bishop

The art of losing isn't hard to master;
so many things seem filled with the intent
to be lost that their loss is no disaster.

Lose something every day. Accept the fluster
of lost door keys, the hour badly spent.
The art of losing isn't hard to master.

Then practice losing farther, losing faster:
places, and names, and where it was you meant
to travel. None of these will bring disaster.

I lost my mother's watch. And look! my last, or
next-to-last, of three loved houses went.
The art of losing isn't hard to master.

I lost two cities, lovely ones. And, vaster,
some realms I owned, two rivers, a continent.
I miss them, but it wasn't a disaster.

--Even losing you (the joking voice, a gesture
I love) I shan't have lied. It's evident
the art of losing's not hard to master
though it may look like (Write it) like disaster.

He wishes for the Cloths of Heaven
W.B. Yeats

Had I the heavens' embroidered cloths,
Enwrought with golden and silver light,
The blue and the dim and the dark cloths
Of night and light and the half light,
I would spread the cloths under your feet:
But I, being poor, have only my dreams;
I have spread my dreams under your feet;
Tread softly because you tread on my dreams.

Friday, May 18, 2007

Mental Illness I

As we start talking about some psychiatric issues, the question of mental illness comes up. What exactly is mental illness? Unlike most other diseases, there are no certain diagnostic criteria for mental illness. To diagnose clinical depression, someone has to meet 5 of 9 criteria; this is very different than diagnosing anemia for instance. And what's normal? What's abnormal? Indeed, is a disease like Attention Deficit Hyperactivity Disorder (ADD/ADHD) abnormal? Evolutionarily, humans weren't built to sit in front of computers for hours at a time or to learn at desks in a classroom. As societal norms change, what was once normal may become abnormal. Indeed, different societies have different mental illnesses. We learned that psychiatric abnormality should be focused on questions of the individual's satisfaction and distress as well as ability or inability to engage in satisfactory relationships and function in society.

Thursday, May 17, 2007

Animal Rights

Today, I saw a few animal rights activists protesting against research on animals. Their argument is understandable. Animals are bred for the sole purpose of experimentation, which often requires them dead. It may seem cruel to bring something into this world only to kill them a number of weeks later. Some animals are genetically engineered. Animals might have the right not to be used for experimentation.

However, I do support animal research. Like many med students, I did research on animal models as an undergraduate. It wasn't easy, and there is indeed a process of desensitization. But in understanding the nature of scientific research, I have come to terms that the use of animal models in research can be justified by the medical advances and knowledge that results from such work. Indeed, penicillin, organ transplant, and vaccines for polio represent Nobel Prize winning work that took place in mammals. There are key experiments and experimental questions that simply cannot be answered without animal work.

Yet I do acknowledge that only such questions should be addressed with animal research; if there are other methods for elucidating a problem, those should be explored. Animal lives should not be taken needlessly. And regulation is important, no matter how much scientists dislike it. Animals should receive a certain standard of care and experiments should be reviewed by independent bodies.

Wednesday, May 16, 2007

Drug Reps

Today, I heard a pretty fascinating talk by an ex-pharmaceutical sales representative about his perceived interaction between drug companies and physicians. The problem is that each group is motivated by completely separate things. Physicians are (ideally) oriented towards the patient's best interests; the ethical duty of a doctor is to serve his patients. On the other hand, pharmaceutical companies want to make money; for them, the bottom line is their shareholders. This dichotomy creates a great tension between the two groups. Pharmaceutical companies will go to an incredible extent to affect a physician's prescribing habits.

Sales reps are chosen because they charismatic, good-looking, friendly, and well-dressed. They are the only ones at your clinic without complaints, not trying to get you to sign forms, willing to bring you lunch, distributing free pens and pads of paper. At the end of the day, they sympathize with you for your long hours; they say something like, "Let's grab a bite to eat; it's on me. We won't talk drugs, I promise." And they don't. Yet, your prescribing habits change to favor them. They employ psychological tactics like good cop/bad cop. They have learned to speak the lingo and cite the studies that support their drug, even if they haven't taken a single biology class past high school. They know how to downplay the downsides of their drugs but remind you of the weaknesses of their competitor's. They can infiltrate your clinical care team by learning which flowers your secretary likes and when her birthday is or convince your nurse that their drug is ideal. So when your nurse proposes it, your defenses are down, but they still get at you, all the same. These drug reps build up entire databases of your information; they know how old your kids are, where you went to medical school, what books you read. They also know your prescribing habits (by buying compiled information from pharmacies) and can direct their 5 minute talk to reinforce some of your habits and change others.

Whether this is ethical or not probably depends on your ethical schema. It might make perfect sense to a utilitarian (you have to maximize the good of your shareholders) or an objectivist (you want to maximize your own effectiveness and happiness). But it seems ethically reprehensible to a Kantian (which I happen to be - a topic for another post). But regardless, companies do this. It's a cutthroat world in marketing out there.

So everyone should be aware of the marketing tactics used by pharmaceutical companies to change a physician's prescribing habits. One should also know that most of the influence of a drug rep is not from the information they give, but rather from the relationship they develop with the physician. A physician can limit the influence of the drug companies by opting out on giving away their prescribing habits. A physician should always keep in mind that his duty is to his patient and to eliminate those with undue influence on the care of his patients.

Tuesday, May 15, 2007

Saturday Night Palsy

A palsy often refers to nerve damage leading to paralysis of a body part sometimes associated with loss of feeling or uncontrollable movements. I was amused to learn about Saturday Night Palsy, radial neuropathy that occurs when a drunk person falls asleep with the backs of his arms compressed against a bench or bar edge or other hard object. It can cause transient paresthesias (tingling), numbness, or loss of hand motor function.

Monday, May 14, 2007


Last week, we had a session at the clinical skills center to learn how to use otoscopes and ophthalmoscopes. I'm not sure which is harder, using the scopes or spelling them. The otoscope is pretty straightforward; it's used to look into the ear and infer whether there is an infection, mass, etc. The ophthalmoscope is used to visualize the retina, vessels of the eye, and optic disc (where the optic nerve emerges). This can help a physician diagnose or assess the severity of hypertension, diabetes, glaucoma, cataracts, retinal detachment, and other eye disorders.

Using the regular ophthalmoscope is really difficult. I can manage to get a vessel, but when I try to trace it to the optic disc, I always end up losing it. However, at the beginning of the year, the bookstore people convinced me to buy a "Pan-Optic" ophthalmoscope. This thing is super cool! It makes visualizing the retina a whole lot easier; I managed to see the optic disc and everything. It also allows you to use either eye and takes away a lot of the difficulty of maneuvering the scope around. I recommend it to anyone thinking of going into ophthalmology or neurology.

Sunday, May 13, 2007

Mother's Day

Kate just reminded me that I should wish my UTEACH mom a Happy Mother's Day as it's her first. Isn't that super sweet?

The Family That Couldn't Sleep

I recently read The Family That Couldn't Sleep by D.T. Max. It's a very narrative book about Fatal Familial Insomnia (FFI) and other prion diseases. FFI is a scary yet fascinating rare disease where plaques develop in the thalamus, leading to hallucinations, panic attacks, complete inability to sleep, dementia, and death. It really highlights how central sleep is in our lives. The author describes the history of this and related diseases: kuru, scrapie in sheep, bovine spongiform encephalopathy ("mad cow disease"), chronic wasting disease in deer, and Creutzfeldt-Jakob disease. Prions are quite fascinating entities, and one of the Nobel prize winners for prion discovery, Stanley Prusiner, is at UCSF. The book, however, takes a heavy historic and narrative approach, and I wish there was more science. The author is quite opinionated about certain people and doesn't seem to be objective, but it makes the reading interesting. For those who like history of medicine, it's a suggested read.

Saturday, May 12, 2007

Neurological Exam

We recently learned to perform the neurological exam. The key is to keep it logical. There are so many different parts and tests that you have to maintain a set way of conducting the exam so that you don't omit any key components. The other issue with the neuro exam is that a lot of it is very subjective. We have to assess muscle bulk, tone, and reflexes, and I find that difficult. Only through examining many, many patients do you get an idea of the range of "normal." Everyone has a different baseline for these things.

We spent a few hours practicing on classmates, learning to get the patellar reflex and do the finger-nose-finger test for coordination. It's fun playing around with reflex hammers and tuning forks. Then that very afternoon, I had my neurology apprenticeship. I was assigned to a neurology resident at San Francisco General Hospital with a few other classmates. We each got individual patients to see. After spending some time taking a history and doing an examination, we presented our patients in a sort of "Morning Conference" fashion. Then we rounded on the patients and discussed pertinent findings. It was interesting! Doing the neuro exam was very difficult because I did things out of order, forgot important maneuvers, and didn't know how to evaluate my findings. But it's something to keep working on.

Thursday, May 10, 2007

Stroop Test

The Stroop test is a cognitive neuroscience test to demonstrate interference in the reaction time of a task. It's pretty cool and influential in experimental psychology.

Say the color of the font/ink of the words as fast as you can:
1. Red Green Orange Purple Green Blue Red Blue Purple Orange

Green Red Red Purple Blue Orange Blue Green Purple Orange

You'll notice the second line is significantly more difficult than the first line.

Wednesday, May 09, 2007

Figuring Out the Eyes

"And when I see you / I really see you upside down / But my brain knows better / It picks you up and turns you around." - Death Cab for Cutie, "A Lack of Color"

Tuesday, May 08, 2007

Brief Sojourn

After the exam, I attended the Hamilton Research Symposium at Mission Bay on "Life in Extreme Environments." The talks were bizarre, but interesting. They focused on microbes living in unusual places: H. pylori in the acidic stomach, bacteria in termite hindguts, and thermoacidophiles in deep sea vents. Weird stuff. People do research on this? Actually, it didn't sound too bad; researchers are forced to go to places like Costa Rica, Australia, and Japan to find termites or deep sea vents. I can't say I learned an incredible amount that's applicable to what I want to do, but at least it widened my perspective on...stuff (I guess).

The next day, I made up a preceptorship I missed when I was sick. Because of the nature of my preceptorship, I don't do too much physical exam, but I've learned that even without an exam, I can make many useful observations. "In general, the patient is an elderly woman in no apparent distress who appears her stated age and is confined to a wheelchair." And even some remarks about her appearance, speech, movements, extremities, and mental status.

I then flew home where I had a really relaxing time with family and absolutely no brain, mind, or behavior.

Monday, May 07, 2007

BMB Quiz

Last week we had a "quiz" in BMB (as Dr. Lowenstein calls it). It wasn't too bad. I like a lot of the material covered in the first two weeks. While anatomy is anatomy, it's very cool to be able to localize lesions from neurological findings. If you know where all the cranial nerves exit and how they travel, by knowing which deficits a patient has, you predict what part of their brainstem or brain was injured. We also went into some depth on spinal cord pathways, and I actually find that very interesting; light touch and vibration travel in different pathways than temperature and pain, so you can lose ability to feel light touch, but retain the ability to feel pain. I finally managed to learn about reflex arcs. The cell biology and developmental biology stuff wasn't bad. The anatomy practical in the afternoon was fairly tough; there were 70 identifications to make, and it took an hour. But it was a great relief to be done.

Sunday, May 06, 2007

Home Visit

One of our assignments was to do a home visit for a patient, a very "FPC" thing to do. This would allow us to build a stronger relationship with the patient, see them in a comfortable environment, and assess their living situation for any alarming health problems. This assignment was unreasonably easy for me; my preceptorship takes place at a nursing facility, and all the patients live there. So at the end of a preceptorship, I asked a patient if she would mind me coming up to visit her apartment, and the home visit was arranged.

I did the usual things, asking her about her life, how her age and chronic illnesses affect her daily living, and her general health. I checked her medications and made sure she wasn't having any problems with them. I assessed the home for hazards like extension cords, poor lighting, lack of handlebars in the bathrooms. But obviously, as she lived in a nursing care facility, there really weren't any problems. But she enjoyed the company, the conversation, and the chance to discuss her everyday health and how it affected her.

Saturday, May 05, 2007

Neuroscience Nights

This block they introduced something called neuroscience nights, which happens about once a week. It's mainly geared to those who want to learn about basic neuroscience research. We read several papers and have a discussion with an expert in the field. Last week, the neuroscience night was on channelopathies (specifically hypokalemic periodic paralysis). Channelopathies are a family of diseases caused by mutations in ion channel genes, such as myotonia, seizures, headaches, dyskinesia, episodic ataxia. This correlated well with my journal club presentation, since that, too, was a channelopathy. I think it's great that they encourage more learning about techniques of investigation, critical thinking, and basic science stuff.

(Image: Voltage gated sodium 1.4 channel, marked with mutation locations leading to channelopathies)

Friday, May 04, 2007

Journal Club II

Pain is an interesting concept for philosophers because it is an incredibly subjective experience. We all know what pain is, but it's very hard for us to describe what it feels like to someone else. We ask patients to use words like sharp, dull, burning, aching, crushing, but pain is often indescribable. Indeed, 20th century philosopher David (Kellogg) Lewis wrote a seminal philosophy of mind paper entitled "Mad Pain, Martian Pain" trying to elucidate this topic.

What interested me about the article I presented at Journal Club is that this makes some sort of objective connection to the subjective experience of pain. When someone comes in with a fever, we can test it with a thermometer. When someone comes in complaining of excruciating pain, what do we have? a lie detector test? But this paper is evidence that measurable biologic phenomena relate to the experience of pain (in fact, this concept is called nociception).

Anyway, I found presenting at Basic Sciences Journal Club to be a great experience. I learned a whole lot doing a brief literature review and studying voltage clamping. The BMB (Brain, Mind, Behavior) faculty were really supportive in helping me understand the tougher aspects of the paper. Putting together a presentation is always a learning experience, and I opted for fewer slides (only twenty-some for 45 minutes) but mostly because I had to study for an exam. I did manage one really bad pun ("at the exact moment in which you see a flow of charges down a voltage gradient, you are observing a current event"), but no one walked out so that was good. I also showed a clip of a House episode with a patient who couldn't feel pain. All in all, it was both fun and educational.

(Image: Picasso - Guernica)

Thursday, May 03, 2007

Journal Club I

Last week, I presented a Nature 2006 paper at Basic Sciences Journal Club on a gene mutation which confers an inability to experience pain. It's a pretty fascinating paper, demonstrating a remarkable journey from a very rare phenotype to identifying the gene and confirming that the mutated protein is likely to cause the presentation of the disease. The paper spends some time describing these patients: they have never felt any pain on any part of their body at any time. It's pretty crazy. They have normal sense of light touch, vibration, temperature, proprioception (where their limbs are), and tickle. But the lack of pain sensation means they never learn what things are harmful to them; one of the people studied was a boy who did street theater where he stuck knives into his arms and walked on burning coals. So lack of pain is really not a gift, but a danger to these people.

They identified several families with this phenotype and mapped the disease gene through positional cloning with microsatellite markers. They finally identified SCN9A as the mutated gene in these patients. SCN9A encodes an alpha subunit of a voltage-gated sodium channel found at the ends of nociceptive (pain-sensing) neurons. Sodium channels often start action potentials, signals which communicate to the brain. It makes sense that if you had nonfunctional sodium channels at the ends of pain-sensing neurons, you wouldn't feel any pain.

The authors then confirmed this by doing in vitro studies with voltage-clamping to show that indeed, these mutations led to nonfunctional sodium channels. Although this was expected, I spent some time going over the technique and interpretation of patch-clamping and voltage-clamping. In the end, the authors had demonstrated that mutations in this sodium channel leading to nonfunctional proteins causes this very strange phenotype of insensitivity (or indifference) to pain.

(Cox, JJ et al. "An SCN9A channelopathy causes congenital inability to experience pain." Nature Vol 444, 14 December 2006, p.894-898)

Wednesday, May 02, 2007

MedTeach II

Our second lesson was on the respiratory system. I did a station on mechanics of breathing for one class and smoking for the second class. For these stations, we had models of lungs and a box of things found in cigarettes: nail polish remover, PVC pipe, bug spray; hopefully, this will reinforce anti-smoking messages for the students. We also had a station on lung anatomy and lung diseases like asthma. At the asthma station, we had everyone breathe out of straws and licorice to see how difficult it is to move air with increased anatomic dead space.

Our most recent lesson was on the digestive system. I ran the station on anatomy with specimens of small intestine and liver. Those were pretty good specimens, as their texture is completely different and I could have the kids try to determine whether the intestine was small or large. We also had a station on nutrition, upper GI stuff (saliva, peristalsis), and a model of the GI tract.

In any case, I really enjoyed doing this and learned a lot. I could really see some of the students trying hard to learn, fascinated by the human body. I became a better teacher as time went on, from organizational things like time management to presentation of material suitable for their level. MedTeach is a great experience.

Tuesday, May 01, 2007

MedTeach I

I've gotten involved in a program called MedTeach where groups of medical students teach a few lessons at local elementary schools. I really like working with Stephanie and Sarah as well as two fantastic teachers at Alamo Elementary in the Richmond district. We teach 4th and 5th graders, and they are absolutely wonderful and cute. They're enthusiastic, excited, and smart! This whole program is funded by a grant which allows us to get resources like organ specimens, posters, models, and kits.

We have taught 3 of 4 lessons so far. We structure our lessons with 4 stations for small groups of students to rotate through. Our first lesson was on the cardiovascular system with stations on anatomy, heart disease, blood cells, and pulse. It was really fun! I ran the anatomy station, and I had an actual heart for all the students to see and touch. In the pulse station, we taught the kids where to feel major pulses and to see how exercise changes pulse. We were able to get fake microscopes ("microslides") to show pictures of red blood cells and white blood cells. And we had a good station on atherosclerosis.

The kids are super receptive to the program. They really like the interactive nature. They ask good questions and some of them have a lot of background knowledge. It's really fun to work with them, and I think the teachers appreciate it too. Hopefully we can get them interested in science.