Archive for the 'Science/Medicine' category

 | August 11, 2010 5:34 pm

Yesterday, while I was looking through Twitter, I came across an extremely interesting blog post by Krystal D’Costa, the author of the Urban Ethnographer.  (Though perhaps not for the reasons she intended.)

In her post, D’Costa asks the following question:

Are we losing our sense of social appropriateness? Or are transgressions more exaggerated now that we interact more frequently in the digital space where important social cues tend to be missing?

As tentative evidence toward her claim, D’Costa talks about an experience she recently had while riding a train home from work.  On that particular commute, she ended up sitting next to a gentleman who wished to talk.  D’Costa, however, did not.  To get her point across, D’Costa gave all of the non-verbal cues of indifference.  But the other passenger just ignored them.

Here’s how she describes her experience:

Within a few minutes, an older Jewish man shambled up the aisle, hoisted his very heavy briefcase up on the overhead rack, and muttered loudly: “I missed this train by ten seconds last night.” I looked up in surprise because my commutes on the LIRR (Long Island Rail Road) are fairly quiet affairs. Most people are either sleeping or trying to finish some work or reading.

Having noticed my attention, he seemed to be waiting for a response. So I said, “Wow, that’s awful.” I should have kept reading—and honestly, I knew that was the case the instant that I saw his face: he was looking for someone to talk to. Anyone would have done. I just happened to draw the straw that night.

He plopped down in the seat and continued: “Oh, yeah. Isn’t that terrible? Ten seconds! Now, five minutes is a different story, but ten seconds makes you feel bad. Well, I don’t have a wife to keep track of these things, so what can you do?”

Trying to head him off, I gave him a sympathetic nod and went back to my laptop but the invitation had already been offered and he continued on—loudly. “I can’t find a nice girl to marry me. All they want is money. That’s how they’re being raised. Once they hear I’m a lawyer who makes less than $100,000.00 a year, they’re done with me. It starts when they’re young; their mothers teach them to look for men with money. They would rather be single and childless than married to me.”

Wincing at his words, I thought in my head, I think I can understand why, and I’m sure a few passengers around us probably had a similar thought as well. He continued in this way for most of the trip, talking endlessly despite the fact that I made a great show of working diligently on my laptop.

Finally, I cut him off explaining that I needed to transfer trains, and got up to wait by the door.

Show me more… »

 | July 26, 2010 3:34 am

Isolating ideas through reduction and simplification is one of the cornerstones of modern science. It’s the system that has allowed us to put men on the moon, understand the inner workings of the heart and split the atom. By reducing a system to it’s most essential components, and then analyzing how the components interact, we have greatly increased our understanding of complex physical, chemical and biological phenomenon.

But even though reduction is essential in the testing and presentation of scientific thought, I’m starting to realize that it is often far-removed from the processes that generates, incubates and prepares it. It is simply too neat and tidy.  And discovery and innovation is anything but tidy.

Robin Sloan of Snarkmarket provides a rather neat summary of my thinking (I wish I’d have written it myself):

[Ideas] come from weird combinations, of unexpected collisions that reveal new and interesting relationships. [To produce something innovative] you need to pile it all into your brain and wait for interesting things to happen, not necessarily on the conscious level! [You throw] it all in the brain pot and allow mysterious reactions to occur.

To anyone who is engaged in research, design or science (or training those who will be), it seems like we should be encouraging mysterious reactions. When conducting an experiment, a scientist or thinker may draw inspiration from many sources. She may seek out statistical advice to determine the size of a trial, related fields to see if a more efficient technique exists, or unrelated fields to seek new thrills. Casting a large net in the interest of filling the pot is a spectacularly good thing. It increases the probability that something new and interesting might emerge.

(I think it also requires more than the lip service that we pay to “cross disciplinary collaboration”. The experience of others is simply no substitute for personal familiarity, even if it is relatively superficial. After all, subject experts are most useful when you know the right sort of question to ask, and formulating the right sorts of questions requires knowledge.)

To see why esoteric knowledge can be valuable, consider how high quality typography made its way to the the personal computer. During his time at Reed College, Steve Jobs took a course in caligraphy. This one course sparked an interest in handwriting and typesetting and years later, while working on the Macintosh Project, he hired a team of typesetting experts to create a high quality type and font engine for his new operating system. This group took many of design conventions inherent to high quality typesetting and strove to bring them to desktop computing.

There are countless other stories of designers, writers, scientistis and engineers deriving inspiration from information that was (at best) peripherally related to the question that they were pondering. In some cases, the connection might have only existed in the mind of the individual that made it. When Philo T. Farnsworth, for example, was working on the technology for television broadcast, he solved an important technical problem by understanding how a continuous signal could be broken into uniform sets of information. Where did the inspiration for this technical advance come from?

From his childhood on a farm.

It turns out that there is a great deal in common between the way that a tractor plows a field without ever needing to raise its blade and techniques used to break an image into a single signal of information [1, p. 17-19]. Of course, after the relationship is explained, it becomes obvious. But isn’t that the way of most brilliant insights?

Now what happens if the right ingredients don’t get added to the mix? Or worse, if you deliberately limit your exposure out of the interest of specialization? (Increased depth of knowledge versus breadth of knowledge, better use of constrained time, etc.) Might it be that casting a narrow net actually has a negative effect? Could it stunt the types of questions that can be asked or the variety of ideas that can be pondered?

Whenever I confront the increased emphasis on specialization and the need to seek “selective exposure”, I find myself raising these sorts of questions. Reducation and specialization certainly have their places, but they aren’t at the beginning of the scientific process. When you’re still trying to figure out what questions you’d like to ask, that’s hardly the time to start throwing options away.

I’m willing to bet that the father of reduction himself might even be willing to agree.

References

  1. Paul Schatzkin, The Boy Who Invented Television: A Story Of Inspiration, Persistence, And Quiet Passion (Tanglewood Books, 2004).
 | July 22, 2010 4:39 pm

imageIt is fascinating how history influences the way we do things. For example, did you know that it is a stringent rule that you only mount a horse from the left hand side?

Getting on the left side of a horse is a rule so deeply ingrained in the culture of horsemanship that it approaches the level of law.  Riding instructors drill it into their pupils.  It is the expected form of mounting/dismounting in a group.  You can even be disqualified from some competitive events if you mount from the right side.

There’s all kinds of explanations for how such a trivial behavior became such an ingrained component of horseback riding.  Some of these even suppose a behavioral foundation, claiming that horses best respond to conditioning and training when it is done on the left side.

Of course, such complicated explanations are wrong.

The real reason stems from the middle ages. Back in the day, people wore swords on their left hips. This was done so that they could draw them with their right hands (seeing as most people are right-handed).  Because of the long slashy thing hanging from your left side, it was all but impossible to mount a horse from the right, which would require you kick your left leg (and said cutting object) over the back of the animal.  It was much easier to mount from the left side and avoid problems entirely.

Yet, even though the rationale for mounting on the left side stems from an obsolete practice (carrying swords), we still do it.  Getting on the left side of a horse has become a part of horsemanship culture.  And because you always approach a horse from the left side, and mount a horse from the left side, and condition a horse from the left side, it’s gotten reinforced and some people think that it’s the only way to get on a horse.  That’s what they tell their students, children, or friends; and those people then propagate the behavior even further, even though there isn’t a compelling reason to continue doing so. The right side works just as well.

“Well, that’s nice,” I can hear you saying, “But so what?  Who cares about which side you get on a horse?  In case you hadn’t noticed, most people will never ride a horse.  It’s a hobby!”

Show me more… »

 | July 21, 2010 3:51 pm

Galileo Moon Sketches - Half Full 2For much of human history, Science and Religion have had a very tumultuous relationship.  Both are systems of beliefs that attempt to answer important questions like: “Where did we come from?” and “How did we get here?”  But because they use different methods to arrive at those answers, it is to be expected that they will not always agree.  Nor is there a guarantee that both sides will remain civil.

Yet, even though Religion and Science don’t always get along, this does not mean that their relationship is one of simple antagonism.  Unlike what modern commentators such as Sam Harris or Christopher Hitchens would have you believe, Science and Religion are not enemies.  Far from it, in fact.

If anything, Science and Religion are siblings.  After all, they share a common ancestry and purpose, and it’s only very recently (within the past 150 years or so) that any society – Western, Islamic or Eastern – has attempted to separate them.

Which is perhaps why it is so disturbing to see attempts by philosophers and believers to set them at each other’s throats.  Within the past few years, there has been a virtual renaissance of pro-Science (read, pro-atheist) books that have come out on the market.  These titles have advocated for a fact based morality, declared war on God, and argued that rational/scientific thought is incompatible with religious belief.  In one Slate.com piece, the author actually seemed to believe that Dr. Francis Collins shouldn’t hold a scientific leadership position because he happens to be an evangelical Christian.  (Never mind his hundreds of peer-reviewed publications and significant contributions to the field of genetics.  After all, it’s not like he sequenced the human genome or anything … )

Show me more… »

 | February 22, 2010 5:49 pm

Charles Minard - Railroad Routes

No study of the history of scientific communication can be complete without mention of Joseph Charles Minard, a 19th Century French civil engineer and cartographer.

At the end of his life, Minard created two very famous examples of statistical charts, called flow maps, that every scientist, engineer and student should be familair with.  The first showed Hannibal’s crossing of the Alps (218 BC, Second Punic War), and the second describes Napoleon’s disastrous invasion of Russia (1812-1813).

Both examples are beautiful works of art and masterful examples of evidence.  But they are also more than that, they tell cohesive and interesting stories.  In this post, I thought it might be interesting to take a closer look at the history of Hannibal and Napoleon, and highlight the ways which Minard’s charts help us to explain their eventual outcome.

(Note: High resolution, PDF versions of the two maps are available for download.  These versions have been translated from the original French.  To download, either click on the images, or here for the Hannibal invasion of Northern Italy, and here for the French Invasion of Russia.)

Show me more… »

 | March 24, 2009 1:41 pm

image After nearly 18 months of work, my research group finally published our big study!  It should appear in the journal of the American Heart Association, “Circulation” on April 7, 2009.  This also means that I can finally talk about what I’ve been doing for the last long while.

Atrial fibrillation (AF) is the most common – and perhaps most insidious – form of heart arrhythmia (a change in the normal electrical patterns of the heart) in existence.  It affects millions of people and while it isn’t life-threatening in its early stages, it eventually leads to stroke or heart attack in many of those people who are afflicted with it.

Unfortunately, the current ways of treating AF are completely inadequate.  The class of medication used for treatment (anti-arrhythmics) often cause more problems than they prevent, and interventional treatment is still highly experimental.  It is, therefore, all but a guarantee that the AF will become more serious over time.  Patients cannot be as physically active as they used to be and eventually must adjust to the symptoms of the disease.

A great part of the reason why AF is so difficult to treat is that we lack a good understanding of what causes it.  About fifteen years ago, some researchers in France recognized that the random spots of electrical activity within the pulmonary veins (which return blood to the heart from the lungs) were a likely source of the arrhythmia.  As a result, there is an entire arm of interventional treatment designed to destroy these spots and isolate the pulmonary veins so that bad electrical signals are unable to influence the heart as a whole.  While this is effective in some people, it doesn’t work for everyone.

More recently, other researchers found that AF actually changes the underlying tissue of the heart (a process known as remodeling), which results in other electrical and mechanical adaptations.  These changes make the arrhythmia more serious as well as difficult to treat.  Even though the changes are a sign that the person has a more advanced form the arrhythmia, the only way to ascertain the degree of change is to invasively measure electrical changes from the inside surface of the heart.

That is, until about a year ago.  In the Circulation paper, we describe a method to determine how much the heart has remodeled by using MRI.  We also showed that the degree of change is the single best indicator of how the patient will respond to treatment.  While this may seem obvious, it isn’t something that could be measured easily or safely before.  Now, we have a tool which allows us to see how the heart changes over time in response to AF.  This will lead to a better understanding of the disease, and provide insight in how to treat it.

The image below shows an example of just how good this detection can be.  The first column of images (A) shows a three dimensional model of the human left atrium.  In the top row, we are looking at the back (or posterior) view of the left atrium.  The pointy bits projecting to the left and right are the pulmonary veins.  In the bottom row, we are looking at the atrial septum – part of the wall that divides the heart into left and right sides.  The really interesting information is in the second column (B) which shows a 3D model where two different types of tissue have been identified.  Healthy tissue (shown in blue) and diseased tissue (shown in green).

This particular patient has some diseased tissue, though overall the heart looks fairly healthy.  What is striking, however, is how well this diseased tissue compares to the measurements made by invasive mapping (taken during a catheter intervention).  On the back side (top) we can see a donut of unhealthy tissue, and on the right side (in the septum), we can see a hook of unhealthy tissue.  The location and shapes of these tissue are mirrored on the invasive maps (C).  And all of this can be determined without exposing a patient to radiation or needing to cut them open!

Bioen02 - Circulation Revision - Figure 1 - High Quality

These types of MRI techniques open a whole new branch of research that can be done on the heart that has important implications for more than AF research.  The remodeling and changes observed in AF can be seen in atrial tachycardia and even some types of ventricular arrhythmias.  Moreover, it appears to be related to other conditions, like coronary artery disease or ischemia (from smoking, for example).  More on that later, though.  If interested, you can find the complete text of the Circulation article here.

 | October 20, 2008 12:32 pm

I am happy to note that the first of my papers with the Atrial Fibrillation Group at the University of Utah was published!  The full text can be found here.  While I know that I have an obvious bias, the paper is still very important.  It describes the University of Utah’s methodology for visualizing tissue damage following the ablation.  Further, it lays the groundwork for the next studies: the detection of low voltage tissue prior to ablation, and the determination of what ablation parameters will result in the induction of scar.  All in all, a nice little paper.

As an add on interest, we found that the degree of enhancement (or damage) seemed to relate to how well people did following the procedure.  There are a lot of theories flying around as to why this might be the case.  My own personal theory is that targeted ablation induces a change in diseased tissue.  I was also happy to notice that we aren’t the only people who see it as such.  Our study was of sufficient interest that it was accompanied by editorial comment, as a highlighted article.  Not bad, if I might be allowed a smug moment.

For those that care about such things, here is the citation:

McGann CJ, Kholmovski EG, Oakes, RS, Blauer JJ, Daccarett M, Segerson N, Airey KJ, Akoum N, Fish E, Badger TJ, DiBella EV, Parker D, MacLeod RS, Marrouche NF.  New magnetic resonance imaging-based method for defining the extent of left atrial wall injury after ablation of atrial fibrillation. J Am Coll Cardiol.  2008 Oct 7; 52(15): 1263-71.  PMID: 18926331.

If you’d like to take a look at the full article, you can get the accepted draft from the Science and Technology page.

 | August 17, 2008 11:14 am

Several weeks ago, while working on the revisions for a larger study, I noticed an important trend. Patients who suffer a recurrence of atrial fibrillation following catheter ablation quite often have a history of smoking. “That’s interesting,” I thought at the time. I then successfully stopped thinking about it, so that I could think about other important things. The ability of men to focus only on the task at hand being what it is. While spending time at Dr. Marrouche’s party last night, I ran into Brent Hill. Brent is the research coordinator for the Division of Cardiology. While talking, I mentioned the finding. He got quite excited about it. So excited, in fact, that he thought about co-opting the idea for his thesis. Some additional ideas that he shared:

  1. By what mechanism does smoking cause a recurrence of AF following the procedure? Might it be due to smoking induced ischemia?
  2. Is the effect mitigated by the number of cigarettes which the person smokes per day?
  3. Would offering smoking cessation materials help to increase the effectiveness of the ablation procedure?

Interesting things to think about! I think the next step is to formulate a number of specific hypotheses and draw up a formal proposal. At that point, it would be interesting to approach Marrouche and get his take on it.

Update

Though it may have been interesting to further think about and develop a map of how AF and smoking relate, I do not think that will ever be a possibility; unfortunately. Due to a number of personal reasons, I have decided that it is time for me to leave the AF group. I have greatly enjoyed the time that I have been able to work with the people in the group, but it is possible that my future lies somewhere outside of medicine. I will be posting a “Swan Song” shortly which describes my thoughts of how the various projects interconnect, but that will be my last thoughts on atrial fibrillation and its treatment.