Sunday, February 18, 2018

Keeping Human Organs Alive Longer Before Transplantation

One of the practical limitations to transplantation of organs from a recently-deceased donor to a recipient is the length of time that human organs remain viable outside a human body. Even if the organ is immediately cooled on ice, it's only a matter of hours before it is no longer considered healthy enough for transplantation. Sometimes it would take too long to transport the organ from where it is harvested to where it is needed, even if pilots and planes were standing by to transport it.

That may be about to change. Several companies (OrganOx and Transmedics) are working to extend the time during which human organs can be kept alive outside the body for up to a full day. This is being accomplished not by cooling the organ, but by keeping it warm and perfused with blood throughout storage and transport so that the organ's metabolic requirements are met and it can continue to function. The techniques require some expensive equipment (much more expensive than just a cooler of ice!), but if lives can be saved the extra cost may just be worth it.

And if we are allowed to dream, if the time of organ storage outside a human body could be extended to weeks or even months, it might be possible to establish human organ banks in some distant future!

Thursday, February 8, 2018

New Treatment for a Penile Dysfunction Condition

Peyronie's disease - the disease we never knew existed until there was a cure for it. TV commercials about the condition ask cryptically "Are you curved below the belt?". It took me a minute to figure that one out! In fact, Peyronie's disease is a relatively rare condition in which scar tissue in the penis causes marked curvature of the penis during an erection, leading to painful erections and problems having sex. What causes the scar tissue to develop is generally unknown, although prior physical injury is suspected in many cases.

In December the FDA approved the first non-surgical treatment for Peyronies's disease after reviewing the results of two studies. Shortly thereafter the company producing the treatment, Endo Pharmaceuticals, launched an aggressive disease awareness and product marketing campaign. And why not? There's a lot of money to be made. Treatment will cost $26,000 in addition to the doctor's fees. Treatment involves 8 injections into the penis six weeks apart of Xiaflex, a collagenase derived from the bacterium that causes gangrene.

Endo Pharmaceuticals says that "3-9% of adult males worldwide are estimated to have Peyronie's disease", but no evidence is presented to back that up. Estimated by whom? Sigh. For now we'll just have to put up with those annoying ads.

Monday, February 5, 2018

IQOS Smokeless Cigarettes

Is it possible to produce a "smokeless" cigarette that will do less harm than regular cigarettes? The tobacco company Phillip Morris has created a device called IQOS that gently heats tobacco, rather than burning it. The company says that IQOS reduces the level of toxic chemicals produced, compared to regular cigarettes, by over 90%, and therefore it is a healthier alternative than regular cigarettes.

Phillip Morris has spent billions developing IQOS, but is it a good idea? Some health officials are skeptical. For one, the device still delivers nicotine. Health officials are concerned that IQOS may produce a whole new generation of smokers addicted to nicotine. And while nicotine may cause less harm than the toxic chemicals in cigarettes, is also has no known health benefits, so why encourage its use?

Then there's the FDA. Last month an advisory panel to the FDA recommended against approving IQOS for sale in the U.S., saying that while it may be true that IQOS generates fewer of the harmful chemicals found in cigarettes, that does not prove that IQOS would cause less harm to human health. It may seem like a fine point and it may be unlikely that IQOS would harm human health (much), but the FDA advisory panel is technically right.

In the meantime IQOS has gone on sale in Japan, so perhaps in time we'll know more about how it affects human health. I just hope for the sake of Japanese smokers that Phillip Morris is right. that IQOS at least proves to be less unhealthy than regular cigarettes.

Friday, February 2, 2018

Raw Water

What's in the water you drink? Pure water is just H2O - it contains just hydrogen and oxygen. But water from almost any natural source may contain a lot of other things, depending on where the water came from and how it was treated before it gets to you.

The latest craze is drinking raw water, loosely defined as water from a natural source, untreated and unfiltered. Proponents argue that it is better for you than filtered or treated water because it still contains certain useful minerals such as sodium, calcium, and magnesium, and that it is free of certain chemicals that may be added during water treatment, such as chlorine and fluoride. One seller of raw water even suggests that their water may be "naturally probiotic", meaning that it contains probiotic bacteria.

Naturally probiotic - really? If raw water contains bacteria, isn't it just as likely that some of them could be bad for you? And what about parasites and toxic chemicals that may be found in the environment? Do you want to take that risk? It's up to you.

Monday, January 22, 2018

Global Temperatures Continue to Rise

The last two years have been the hottest two years ever recorded, according to scientists at the National Aeronautic and Space Administration (NASA). The hottest year was 2016, followed closely by 2017. In fact, the five hottest years ever recorded going all the way back to 1880 (when it first became possible to measure global temperatures with any accuracy) have all been since 2010.

Climate deniers are beginning to look a bit foolish, don't you think? But they can still argue that we don't really know what is causing global temperatures to rise (translation; there's insufficient evidence that global warming is being caused by human activities), and to use that argument as an excuse for not doing anything about it.

They win that argument at their own peril, in my view. By the time we all agree on what is causing global warming and what should be done to mitigate it, it may be too late - the climate will be changed for perhaps hundreds of years, if not permanently. Humans will have to adapt to very different climate conditions than exist today. Lucky me, I won't live long enough to see it.

Saturday, January 20, 2018

Development of Antibiotic Resistance in the Natural Environment

A report from the United Nations Environmental Program offers a useful summary of how the presence of low concentrations of antibiotics in the environment can lead to bacterial antibiotic resistance.

According to the report, antibiotics make it into the natural ecosystem in three ways; 1) via improper disposal of unused prescriptions of antibiotics, 2) through the inadequate treatment of wastewater, and 3) in agricultural waste as a result of the heavy use of antibiotics in farm animals. The report suggests that these low concentrations of antibiotics contribute to antibiotic resistance. In other words, it's not just the over-prescribing of antibiotics for humans that leads to antibiotic resistance; it's also a slow, ongoing process as a result of current environmental contamination. In addition, we know very little about how certain other substances in the environment, such as heavy metals, further contribute to antibiotic resistance.

If the report is correct, we may need to pay more attention to sewage and wastewater treatment, as well as working toward curbing the over-prescribing of antibiotics for farm animals, as well as for humans.

The report contains a handy visual flow chart (p. 15) that teachers might use to explain this subject to students.

Monday, January 15, 2018

You and Your Microbiome

Two recent findings on different subjects highlight the importance of the community of bacteria in our gut, called our microbiome.

First up is an article detailing the effects of exercise on our microbiomes. Researchers at the University of Illinois Urbana-Champaign showed that a few weeks of moderate exercise by people who were not exercising previously alters the number and types of bacteria found in their guts. And although the types of bacteria were not the same in everyone, in general there were increases in the types of bacteria that reduce inflammation, fight insulin resistance, and enhance metabolism. The changes were not permanent, however; the bacterial community reverted back to the original state when the subjects quit exercising. The authors speculate that some of the benefits of exercise may be due to the effects of exercise on our biomes. A New York Times article discusses this topic in some depth.

On an entirely different subject, scientists may have discovered at least part of the explanation for why dietary fiber is good for you. It turns out that although we humans can't digest dietary fiber, some of the bacteria in our gut can. It's their major food supply! More dietary fiber means more bacteria, some of which reward us by supplying us with certain nutrients that we can use. In addition, bacteria signal the cells lining the gut to produce more mucus. A thick mucus coat on the inner surface of the gut is important; it protects the gut cells from damage and prevents the immune system from overreacting to the presence of so many bacteria. A more detailed explanation of this subject can be found here, for those who are interested.