Thursday, July 27, 2017

Usain Bolt's Unusual Running Stride

There's something unusual about Usain Bolt, other than he's the fastest sprinter, ever. He's also unusual in that his running stride is asymmetric. According to researchers at Southern Methodist University, his right foot strikes the ground with 13% more force than his left, and his left foot stays on the ground 14% longer than his right.

Most runners have close to symmetrical strides, with left-right differences of less than 3%. Running coaches generally assume that symmetry is desirable for speed optimization. But is it? It's possible that Usain Bolt has subconsciously stumbled onto something (no pun intended) that improves humans' running speed. On the other hand, it is just as likely that his body has adapted to the fact that apparently he has slight scoliosis; his spine curves slightly to the right, causing his right leg to be a little shorter than his left. If that's true and if asymmetry is generally not desirable, then his rise to the title of fastest human is all the more remarkable.

Sunday, July 23, 2017

Washington State's New "E-DUI" Distracted Driving Law

The State of Washington has had enough of distracted driving.

Under a new law that takes effect today, using a hand-held electronic device of any kind while operating a motor vehicle is a primary driving offense, meaning that the police may stop you for that offense alone. The law goes beyond prohibiting texting or talking on a handheld phone; it prohibits checking Facebook, reading texts and e-mails, and even just holding an electronic device while operating a motor vehicle, even while stopped at a stoplight. Violators will be issued a distracted-driving citation and fined $136 for the first offense. The violation will go on the driver's record and their insurance company will be notified, which might cause their insurance rates to go up. A second offense will lead to a larger fine.

Drivers can still talk on their hands-free phone, and they can use a hand-held phone to contact emergency services. And they are still allowed to employ the "minimal use of a finger" to change an electronic device's function (preferably to turn it OFF).

The new law makes all forms of distracted driving secondary offenses, meaning that motorists who are stopped for a primary offense (such as running a red light) can be fined another $99 for "any activity not related to the actual operation of a motor vehicle". That might include reading a book or newspaper, eating, drinking, applying makeup, or reaching for something on the floor while driving.

So what are you supposed to do while driving? Concentrate. On driving.

Saturday, July 15, 2017

FDA Set to Approve the First Gene Therapy Procedure

An FDA advisory panel voted unanimously this week to recommend that the FDA approve the first gene therapy procedure.  The procedure is for the treatment of B-cell acute lymphoblast leukemia in children that have resisted treatment by other methods.  Final FDA approval is expected by October.

The procedure involves removing millions of a type of white blood cells called T cells from the patient, genetically modifying them to enhance their ability to attack abnormal B cells (the type of cell that becomes abnormal in this type of leukemia), and then returning them to the patient.  So far the technique has been tried on 63 patients.  Fifty-two of them are still in remission (for an 82% remission rate); the other eleven died.  The very first patient to receive the treatment was 12-year-old Emily Whitehead.  She was treated 6 years ago and is currently cancer-free.

It would seem to be a no-brainer that this procedure should be approved.  However, although the FDA panel did recommend approval at this time, a word of caution is in order.  We still don't know how permanent alteration of a patient's T cells might affect the their health in the long-term.  To try to answer that question, patients who undergo the procedure will be entered into a registry and followed for at least 15 years.  But so far, at least, everything looks good.

Now for the bad news.  The procedure is likely to cost at least $300,000.

Monday, July 10, 2017

Baby Sickened Because Mother Eats Placenta

The Centers for Disease Control and Prevention (CDC) reports that a baby in Oregon was treated for Group B streptococcus infections - twice in a week! - apparently because its mother was ingesting improperly prepared placental pills.

Although the CDC does not recommend placenta consumption, it's a fad in some circles that just won't go away. According to CNN News, devotees include Kim Kardashian and Alicia Silverstone. There is even a group called the Association of Placenta Preparation Arts that claims to have "placenta preparation specialists" who know how to prepare the placenta properly for ingestion. As if there actually is a "proper" method for preparing the placenta for ingestion. Members of the group believe that placenta consumption has benefits including preventing postpartum depression and increasing milk production.

Pardon me, but there is no evidence that these people know what they are doing (see this blog July 19, 2007 and June 13, 2015). Feel free to check out their website, compare it to the CDC report and any available scientific evidence, and make up your own mind if you wish.

Wednesday, July 5, 2017

Experience Matters When It Comes to Driving

According to a study by the AAA Foundation for Traffic Safety, people become better drivers with age and experience, at least until old age sets in. For the same number of miles driven, rates of both crashes and deaths are relatively high among 16-17-yr-olds, decline steadily with age until 70, and then rise again.

None of this should be a surprise; new drivers lack the experience that comes with a long history of driving, and older drivers are beginning to lose their sensory acuity and reaction times. But the numbers are startling. For the same number of miles driven, 16-17-yr-old drivers are about 6 times as likely to crash (and to die in a crash) as the safest group of drivers, 60-69-yr-olds. So, too, are drivers over the age of 80.

Traffic safety experts have been aware of these facts for some time. That is why some states now limit the conditions under which younger drivers can drive (forbidding driving with other teenagers or driving at night, for example). Most states require older drivers to have a vision test to renew their licenses, and a few states require older drivers to take a written test or a road test as well. All this seems to be working, as the number of people killed in automobile crashes declined more than 25% between 1995 and 2010.

Incidentally, teen crashes and deaths go up about 15% in the summer, when teens are out of school and may be driving more than during the school year.

Saturday, July 1, 2017

A Skin Patch to Deliver the Flu Vaccine - An Update

Remember the skin patch (this blog, Mar 13, 2014) that was being developed to deliver vaccines without an injection? Back then, the patch had only been tested to see how well the dissolvable microneedles of the patch would be tolerated by patients. Last week the same researchers reported that it has now been tested with the flu vaccine.

In the latest study, healthy volunteers received the flu vaccine either by skin patch or by the usual syringe and needle, both administered by a health care worker. An additional group of volunteers were instructed to administer the skin patches themselves, to determine if self-administration was as effective as administration by a health care worker. The results were encouraging. Increases in antibody titers (a sign of immune system activation) were the same in both of the groups that used skin patches and the group that received an injection. Furthermore, the number of adverse reactions was similar in all groups. In other words, the skin patches seemed to deliver the vaccine safely and effectively, even when the patches were self-administered.

So are we done? Not quite. This was a Phase 1 study; a small number of volunteers was recruited to test the method's safety and potential effectiveness (in this case, potential effectiveness was assessed as an increase in antibody titer). A much larger study will be needed to see if the skin patch vaccine delivery method actually reduces the incidence of the flu. A much larger group of patients will be needed, since not everyone in a population gets the flu. This part of the study will probably take at least several more years.

Perhaps some day you'll be able to order a flu vaccine skin patch on the internet, have it delivered through the mail (or by a drone!), and administer it yourself. Today we're one step closer to that goal.