Friday, August 18, 2017

Classifying Cells and Cell Types

How do we describe the types of cells that comprise the human body? Pick any textbook of human biology and you'll find that cells are generally described as belonging to one of four types of tissue (nervous, muscle, connective, and epithelial) based on their broad function. At the next level of complexity, cells within a tissue are further described by their location and more specialized function (smooth muscle surrounding blood vessels; skeletal muscle attached to bones; cardiac muscle in the heart). Beyond these rather broad descriptions, many subtleties between cells are probably lost for lack of a way to measure or define them.

Some scientists think there may be a better way to identify and categorize cells. That's because what actually determines the differences between cells, both in terms of form and function, is the different proteins that they express. Those proteins are determined by the molecules of RNA that are present within the cell, which in turn are determined by which of the cell's genes are active. So to get a more refined measure of a cell's type and its true activity, it would make sense to measure not its shape, its location, or its broad function, but instead to determine which RNA molecules are present in the cell.

A group of enterprising scientists is attempting to do just that, according to an article in The New York Times. They've started with an organism (a type of worm) that has fewer than 1,000 cells. If all goes well, some day we may know a lot more about the incredible complexity of our various cells. And we may have to rethink how we classify cells and describe the relationships between them.

Saturday, August 12, 2017

A New Antibiotic to Combat Antibiotic-Resistant Gonorrhea

Scientists have discovered an entirely new antibiotic that may be useful against strains of gonorrhea bacteria that are resistant to most current antibiotics. It's called closthioamide. It was discovered in 2010, but it has taken until now to learn how to produce it in large enough quantities to be useful.

To date, closthioamide has only been tested in the laboratory on samples of gonorrhea bacteria known to be resistant to most antibiotics. It worked on nearly all of the samples. The next steps will be to try it on animals (to demonstrate its safety) and eventually on humans (to reaffirm its safety and prove that it can cure gonorrhea infections in patients). If all goes well, some day closthioamide may be a new weapon in the arsenal against gonorrhea and other bacterial infections - at least until the bacteria develop resistance to it!

Saturday, August 5, 2017

Prevalence of CTE in NFL Football Players

Repetitive blows to the head can lead to a debilitating chronic brain disorder called chronic traumatic encephalopathy (CTE) later in life. CTE is of particular concern to football players, boxers, and even soccer players. How common is CTE among certain athlete groups, and should we be concerned?

Of course we should be concerned. We would be remiss if we didn't try to find out how and why it is happening to our athletes, and how to prevent it in the future. But we should not scare people needlessly with sensationalist headlines. Take, for example, a CNN news headline: "Study: CTE in 99% of dead NFL players". Or this one in the Daily Mail (a British journal): "Biggest Ever NFL brain study diagnoses CTE in 99% of deceased players' brains". Read more closely and you find that the correct statement is that CTE was found in 99% of deceased ex-NFL players whose brains were donated to scientific research by their relatives (my emphasis). It's not a group that is representative of all deceased NFL players, by any means. It is likely that many if not most of these relatives donated their loved-ones' brains because they already suspected the presence of CTE based on their loved ones' behavioral symptoms while still alive. A definitive diagnosis of CTE can only be made at autopsy. CTE generally isn't looked for in a deceased player without symptoms of CTE, so in fact we really don't know how prevalent it is.

Clearly, CTE is present in many ex-NFL players, and its time to do something about it. The numbers may turn out to be higher than initially thought, and that would be sad. But there's no evidence that it's as prevalent as 99%, at least at the moment. Let's approach this problem with level heads and open minds.

Wednesday, August 2, 2017

Some Sunscreens Slow the Progression of MS in Mice

Sometimes it's better to be lucky than good. Quite by accident, researchers have discovered that ingredients found in Coppertone and other sunscreens may be able to slow the progression of multiple sclerosis (MS). The researchers were studying the known protective effect of UV light on the development of multiple sclerosis (MS) in mice prone to the disease. In the course of these experiments they administered various sunscreens to mice without exposing them to UV light, as controls. Surprisingly, several of the sunscreens slowed the development of MS all on their own. Coppertone was particularly effective. Further tests revealed that two ingredients in particular, homosalate and octisalate, were responsible.

These findings sound like a real breakthrough, but realistically they just represent interesting observations that are worthy of being pursued. A lot more work will need to be done before we will know how these compounds exert their protective effect in mice, and whether they ultimately might be useful in treating MS in humans. The findings also highlight the importance of doing proper controls, because in this case the most interesting findings came from a group of animals receiving sunscreen alone, as controls for mice exposed to UV light and receiving sunscreen. No one expected sunscreen to have an effect on its own.

You can read the abstract of the research paper here. Unfortunately, you'll need access to the Proceedings of the National Academy of Sciences journal in your library to read the entire text. Or you can read a news article about the paper in The Economist.

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.