Thursday, February 27, 2014
See y'all in Behavioral and Neuroscience!
Of particular interest was the use of insulin shock therapy to treat a patient with schizophrenia. This was a positively medieval treatment used from around 1935 to 1960, to little proven effect. In the words of one of the panelists, "the reason insulin shock therapy was perceived as working on schizophrenic patients was that, for the first time, someone was actually trying to kill the patient."
The bizarre idea was to put the patient into a hypoglycemic coma and see if she or he is better when you wake them back up (if you can wake them back up). This only seems humane compared to the alternative treatments of electroshock therapy and lobotomy. Amusingly, electroshock is still in use as a last line intervention, although using much more compassionate methods.
I think my favorite quote from the movie was from the chief nurse: "Nurses are just like husbands. You can abuse them, insult them, work 'em to death, jump all over 'em. They'll take it. But give 'em a bad cup of coffee and you got a revolution on your hands."
TIL: Adenosine deaminase deficiency is the cause of ~15% of severe combined immunodeficiency (SCID), the disease made famous by the "bubble boy."
Wednesday, February 26, 2014
For some humor on the topic of maturity and breasts, enjoy this song by Tim Minchin (contains some explicit and inappropriate language):
Tuesday, February 25, 2014
Saturday, February 22, 2014
When the lecture finally started, no one actually cared about the topic of presentation because we all just wanted to see if the lecturer was the Pharma stooge we had painted him to be that morning. Turns out the presentation was 90% super dry background slides about the physiological basis for the disease process and then a couple case studies of patients that had successfully been treated with the drug. He did a pretty good job of pointing out that the drug in question isn't always right for every patient, though since this topic was his primary area of research, he was solidly in favor of treatment when indicated.
The presenter did seem arrogant and kinda sleazy, but we all agreed it wasn't because of the presentation - that was just him. And like every other presenter we've had, he thought very highly of his own research. Am I glad he had to disclose his conflict of interest? Of course. But am upset that he used a slideshow put together by a drug company that was paying him? Meh. It just showed that he was too lazy to make one himself. I am proud that my classmates and I are involved enough in our own education to have this discussion.
TIL: Artificial growth hormone replacement works really well, sometimes. World renowned endocrinologists can be unpleasant people. All the money in the world still can't buy an interesting presentation.
Friday, February 21, 2014
Thursday, February 20, 2014
|T4 - Note the 4 iodine atoms|
This related tidbit was something I learned while volunteering at a cancer screening clinic last year. The iodine used in the synthesis of thyroid hormone is actually the reason we make and consume iodized salt. The thyroid is the only organ that uses this trace but essential nutrient. This provides a surprisingly easy target for treating thyroid cancers. By injecting radioactive iodine, you can use the body's own natural pathways to target the radiation directly to the thyroid.
Wednesday, February 19, 2014
|Willis' Cerebri anatome from 1664|
|John Snow memorial|
at the former site of
the Broad Street Pump
Friday, February 14, 2014
TIL: Vincent's curtsey is the actual medical term for the clinical sign of urinary incompetence, especially in kids on the playground. I'd include a picture but I think you know what this looks like - crossed legs, partially bent, probably bouncing up and down. This is normal if you've been in a confined space for eight hours and really need to go, but if a kid is at recess and always seems to stand like this, they likely have a medical condition and should see a urologist.
Spinal cord trauma can cause kidney failure in a round about way. The injury paralyzes the urinary sphincter muscles, which are the only muscles around the bladder over which we have direct conscious control. The muscles that compress the bladder work independently and use secondary signals to determine when to contract. Things are wired this way because the sphincters that block the ureters (inlets to the bladder from the kidneys) are weaker than the sphincter to the urethra (outlet used for micturation (peeing)). If you could compress the bladder without opening the urethral sphincter, urine would go the wrong way.
With the spinal cord injury, this is exactly what happens, albeit without the person's control. The urethral sphincter is tonically closed due to the injury. Urine and pressure build up in the bladder until the sphincters that block the ureters are overcome and urine flows back to the kidneys, raising the pressure there. The kidneys cannot function under this pressure and will fail. The take home message is to always check that a patient with a spinal cord injury is either urinarily competent or with a catheter.
Thursday, February 13, 2014
I pride myself in having a wide, diverse network of people that I know, but I don't purposefully meet people just to have connections to exploit. That just seems disingenuous. I understand that it's usually mutual - that when you attend an event explicitly designed around networking, you will only find people there that are hoping to create a similar connection with you. This doesn't make me any more likely to attend, in fact quite the opposite. I also understand that networking is necessary in areas like business and entrepreneurship, but I think it can and should be more organic in medicine.
Imagine you are opening a new medical school and you wanted to recruit the very first class of students. What would you look for in an applicant? They'd need to be smart, studious, caring, and committed. You'd want someone who did well in school because they're smart and studious, someone who voluntarily volunteers (not as redundant as you'd think) because they want to give back to their community, someone who has some experience in medicine to see if they really like it, and someone who sticks with their commitments because the 7+ years of added school they are signing up for will test their resolve.
For premeds classes aren't about fulfilling a curiosity, volunteering is a burden on their schedules, and research is another talking point on their applications. Everything is a means to an end. I'm not saying that they are all in it for less-than-noble motives like job security, financial stability and prestige (though those people exist), but that they have such tunnel vision toward that goal of helping people as an orthopaedic surgeon that they lose sight of all the people they could help along the way.
So back to networking. Doctors are great at it. When you treat thousands of people from every walk of life, you naturally build a strong, diverse network of connections. The medical field is also all about collaboration. Everything the body is connected, so when something goes wrong, doctors often have to consult with other specialists to get the best care for their patients. In this way doctors build a professional network quite organically as well. So why do we need to network outside of our normal interactions with the people around us?
I guess my point is that I'm fine with people going to events like the one that set off this tirade, but I refuse to feel guilty for not attending. </rant>
Say you have a membrane just filled to the brim with receptors. If you have another membrane with fewer receptors it will take more hormone for the second membrane to induce the same response. For either membrane, if you add infinite amounts of hormone you will still produce a maximal response, the second membrane just takes more hormone before it reaches that level (see graph 1 below). In other words, membrane #2 is less sensitive to the hormone.
If you instead have two membranes with the same number of receptors but one has a slightly defective version of the receptor*, that second membrane will not be able to reach the same maximum response as the first regardless of how much hormone you throw at it (graph #2 above). Membrane #2 is still equally sensitive to the hormone, it just can't do as much with the same signal. The new maximum rate will be reached just as fast and with the same amount of hormone, it will simply be lower. Thus the sensitivity has not changed, as represented by ED50 above. ED50 is shorthand for the effective dose to bind 50% of the membrane hormone receptors.
Still confused? Me too. If I find a better way to explain this, I'll come back to it... but don't hold your breath!
*This scenario also works if, instead of damaging the receptors, the number of receptors is reduced to a level so low that it cannot properly trigger the maximal cellular response.
Wednesday, February 12, 2014
TIL: One of my professors casually dropped the word "flocculation" into a discussion today and I half-thought he just made it up. Alas, apparently it was incredibly apt. Flocculation is the process of colloids (suspended microscopic particles (in this case clotting factors on the blood)) precipitate out of solution.
Tuesday, February 11, 2014
Dr. Taussig approached Dr. Blalock with a theory of the cause of and a potential surgical intervention for the very common blue baby syndrome, a condition where the lungs can't get enough blood flow from the pulmonary artery. Blalock and Thomas devise a way to divert blood from the aorta back to the lungs. Thomas masters the surgery on over 200 dogs and guides Blalock though the first surgery on a child. The story is told very well in the 2004 HBO film Something the Lord Made; watch the trailer below:
The University of Padua, founded in 1222, was the major university for Venice. It was located inland from Venice which provided both literal and figurative distance from the Church. This fostered free thought which produced great scientists such as Galileo and Copernicus, and the pioneers of modern anatomy, Vesalius and Harvey.
Saturday, February 8, 2014
Dandy–Walker syndrome is a congenital brain malformation involving the area of the brain around and within the cerebellum. It is named for Walter Dandy and Arthur Earl Walker, two consecutive chiefs of neurosurgery at Johns Hopkins.
Friday, February 7, 2014
In physiology we zoomed in on the nephron of the kidney and looked at the filtering and resorption of various solutes and disease processes that can impede this. This was pretty much entirely review for those of us that have taken physiology before, but it was nice to have a manageable amount of information presented after the barrage we received from biochem.
I also was a patient again today for one of my perpetual follow-up appointments from my bout with cancer two years ago. All clear once again! These visits always put the troubles of med school back into perspective for me. Life's pretty good, all things considered.
TIL: Though there are only 9 essential amino acids (that cannot be made by humans and thus must be consumed in the diet), most of the remaining dozen are still conditionally essential. This means that although the body can synthesis more of the molecule, certain life events (such as childhood growth or pregnancy) or disease processes (like phenylketonuria) reduce or eliminate the synthesis process, requiring supplement through the person's diet.
Wednesday, February 5, 2014
After classes had ended I attended a guest talk by an ethicist and physician, Dr. Barron Lerner, on the changes in medical ethics from the times of his father, who was also a physician, to his own contemporary views. The takeaway was that medicine used to be far more paternalistic, with doctors making decisions on behalf of patients without ever necessarily consulting the patients themselves.
One dramatic example made my classmates and me question whether our current legal and moral framework is truly the best. An ailing woman who was terminally ill and had expressed a desire to discontinue treatment suddenly coded (cardiac arrest). She had not signed a DNR (do not resuscitate) form so the hospital staff went to call the code team, as they are required to do by policy and law. The speaker's father yelled for them to stop, saying that this was wrong and that the moral thing to do was to let the woman die with dignity. The staff called the code anyway and when the team arrived, the speaker's father literally laid his body across her chest to prevent them from doing CPR, and the woman died. Today, such an action would likely result in a lawsuit and/or sanctioning by the hospital. But was it truly wrong? I don't know.
A less serious anecdote was told of an old woman who needed an invasive surgery but wouldn't consent to being operated upon. The speaker's father explained thoroughly explained the need and brought in several other preeminent physicians to do the same. Finally he asked if another doctor from another institution could come take a look. The woman assented but still adamantly refuse surgery. The other doctor was devoutly Catholic. After he recommended the surgery and the woman refused again, the doctor accepted this and then asked the woman if he could pray for her. She was taken aback but said yes. The doctor proceeded to take out his rosary and make a show of his elaborate desperate prayer. The woman had surgery the
TIL: Hippocratic medicine was founded on the principles of the four humors, which though not correct, was the first time disease was attributed to natural causes rather than deities and treatment to physical action by physicians as opposed to intervention by said deities. The Hippocratic age was also the origin of the technique of taking a history and physical, as well as keeping a medical record for empirical research about the efficacy of treatments.