2009 Vodcast Show Notes

Episode #0019 — April 06, 2009
Time: 00:21:25 | Size: 117 MB

Welcome to i on NIH!

Featured in this month's episode are segments about The Physical Activity Guidelines for Americans, how brain cells repair themselves, and a childhood eye disorder called convergence insufficiency.

From the national institutes of health in Bethesda, Maryland – America’s premiere medical research agency – this is "i on NIH"!

Covering health-research topics important to you and the nation, this public service vodcast is your information source from inside all 27 institutes and centers at NIH.

Half an hour, once a month, we’ll show you the excitement of advances and the important information that comes from medical research. And now, here’s your host, Joe Balintfy.

Host: Welcome to the 19th episode of I on NIH, thanks for joining us. We’re mixing things up a little in this show, by starting with our Eye to Eye interview—it’s with Acting Surgeon General Dr. Steven Galson. He’ll share the importance of the new Physical Activity Guidelines for Americans. Also in this episode we have a report on nervous tissue including remarkable footage showing brain cells dividing. Plus we’ll a feature on a childhood eye problem called convergence insufficiency. But as usual, first we turn to Harrison Wein at the NIH news-desk. Harrison, what do you have for us in this month’s NIH Research Update?

Harrison: A study links a higher vitamin C intake with a lower risk of gout. And two new drug combinations fight difficult infections.

Joe: Before we get into vitamin C helping prevent gout, what exactly is gout?

Harrison: Gout occurs when crystals of uric acid accumulate in your joints to cause swelling and pain. Usually, gout affects the joints of the big toe first, but other joints can be affected, too. Left untreated over time, it can cause permanent damage to your joints.

Joe: Ouch. So tell us a little about this study.

Harrison: The study involved almost 47,000 men over a period of 20 years. The men filled out a dietary questionnaire every 4 years, and every 2 years they reported whether their doctor had diagnosed them with gout.

It turned out that men who had the highest vitamin C intake—that’s 1,500 milligrams or higher per day—had a 45% lower risk of gout than those with the lowest daily intake—less than 250 milligrams per day.

Joe: Is 15-hundred milligrams of vitamin C a lot and is there really a connection?

Harrison: Well, to put this in perspective, the recommended daily intake for vitamin C in men is 90 milligrams per day. But the men at lowest risk for gout were taking in at least 1,500 milligrams, and high doses of vitamin C can cause side effects.

We also can’t be sure it really is the vitamin C that helped the men. This was an observational study, which I’ve talked about before on this show. This study is a good example of how you might think you see an effect in an observational study that isn’t really there.

Joe: Yes, we talked about that last episode—supplements and prostate cancer. But can you explain again what you mean here regarding this observational study and gout?

Harrison: Sure Joe. Here’s an example of how a study like this can make it appear like there’s a connection that’s not really there. The men with an intake of over 1,500 milligrams accounted for only about 5% of the men in the study. Those taking less than 250 milligrams accounted for over half. By looking at vitamin use, the researchers may have selected for men who tend to take better care of their bodies. Men who live a healthier lifestyle might clear uric acid out of their bodies more efficiently for a variety of reasons, accounting for why they have less gout.

The researchers tried to account for these factors, but the bottom line is, we have to wait for a rigorous clinical trial—where researchers divide men into groups and give them different amounts of vitamin C—to see if it really has a significant effect on gout.

Joe: Great. We’ll keep an eye out for that, Harrison. Now, the next story is about combination drug therapies.

Harrison: I’m going to talk about two unrelated studies, Joe. Together, they show how far along research has come in the past few years.

The first study concerns tuberculosis. The β-lactam class of antibiotics, which includes penicillin, isn’t effective against tuberculosis, even though it can fight many other types of bacteria. The genome sequence of the bacteria that cause tuberculosis, published about 10 years ago, revealed a reason for this: the bacteria make a protein that neutralizes β-lactams.

Researchers at the Albert Einstein College of Medicine have been studying this neutralizing protein. They found a drug already approved by the FDA that blocks its activity. In this new study, they tested a combination of that drug with a β-lactam antibiotic.

Together, the drug combination inhibited the growth of 13 of the most deadly tuberculosis strains in the lab. Since these are both FDA–approved drugs, they could potentially be used to treat patients with currently untreatable tuberculosis. The researchers are now planning two different clinical trials to test the drug combination.

That’s one study.

Joe: OK, what’s the other?

Harrison: The other study concerns fungal infections, a leading cause of death for people with weakened immune systems. Fungal infections can be extremely difficult to treat. Few drugs are available, and fungi often become resistant to them.

An NIH-funded team led by scientists at MIT and the University of Toronto previously found that fungi use a protein called Hsp90 to become resistant to antifungal drugs. In a separate line of research, several Hsp90 inhibitors are now being tested for their anti-cancer activity. So the researchers combined these with an antifungal drug and found that the combination defeated fungi in the lab.

This is still far from prime time. The scientists need to work out a lot of details before they can try it in people.

Joe: Now what’s the connection?

Harrison: The reason I bring up both of these studies is that they show how a better understanding of how microbes work can lead to new approaches for fighting them. Just a few years ago, scientists were really shooting in the dark to find drugs that combat these diseases. Now, they’re using molecular and structural biology to devise very specific strategies.

Joe: Sounds encouraging, Harrison. And where can people find out more about these studies?

Harrison: Read about these and other research studies in "NIH Research Matters." Go to the NIH home page and click the link on the right-hand side, under "In the News" that says, "eColumn: NIH Research Matters"

Joe: And what’s in this month’s health newsletter?

Harrison: Our cover story for "NIH News in Health" in April is about the new physical activity guidelines for Americans you’ll be talking about on this show. We also have a story about remembering to take your medicine and more.

Joe: And where can people find that?

Harrison: That’s at news-in-health-dot-nih-dot-gov.

Host: Thanks Harrison. Now for our first feature. We’re scooping Harrison and the News in Health newsletter a little bit by bringing you this interview. We’ll hear that adults gain substantial health benefits from two and a half hours a week of moderate aerobic physical activity, and children benefit from an hour or more of physical activity each day. This is according to the new Physical Activity Guidelines for Americans. I on NIH talked to the Acting Surgeon General, Dr. Steven Galson about the guidelines. The first question:

Q: What exactly are the physical activity guidelines?

Dr. Galson: They’re publications that were put together for scientists who were really interested in understanding what is the data that’s been developed over the last few years that helped the Advisory Committee figure out what to recommend. Then there’s a document that’s meant for the general public.

Q: Why is the government publishing the physical activity guidelines?

Dr. Galson: Well, this is the first Federal Physical Activity Guidelines that’s ever been produced, so this is the federal government wanting to make sure that we communicate to the public the importance of physical activity in keeping every American healthy. The best way to reduce your risk of many chronic diseases, to control your weight, to help keep you healthy and energetic is to get regular physical activity. But there has never been a clear statement from the federal government about how much, who can do it, whether there are risks associated with it? So this is trying to really communicate clearly to the public in one voice about physical activity and the benefits of it.

Q: Why are physical activity guidelines important, especially now?

Dr. Galson: I think it’s important because people are asking all around the country how much physical activity should I do? Is it important? You know, can I hook myself up to some machine that I saw advertised on late night TV, and I don’t really need to do exercise? So, it is important now.

I do think it will help the country as a whole. We have a crisis in health care funding in this country. We don’t have enough resources over the next few decades to pay for all of the health care at the current rate that we’re going and so we need to make sure that we’re doing everything possible as a nation to keep our population healthy, not just because it’ll help them fulfill their goals for themselves, but also because of the financial crunch facing the country in health care. So for many, many different reasons, it will help.

Q: What are the physical activity goals recommended in the guidelines?

Dr. Galson: For adults, we should be aiming for a weekly goal and the weekly goal is getting two and a half hours of physical activity every single week. What’s different about this and some previous guidelines that have been produced, they used to say you have to do a certain number minutes every day. This is, in some cases, easier for Americans to follow because you can say, you know, if you’ve missed a few days, you can still catch up on the weekends. So it’s a weekly goal. That’s one very, very important thing. The second is that young people need more physical activity so the recommendation for people up to about age 18 is that they get an hour of moderate or vigorous physical activity every single day. So, for kids, an hour a day, for adults, two and a half hours a week, and it should include, for both kids and adults, not just aerobic activity, but also activity that strengthens your bones and your joints.

Q: How do you fit physical activity into your busy schedule?

Dr. Galson: It takes some effort to get physical activity. I do it really by making sure that if I don’t have time during my busy work week, I make time on the weekends. It’s really a matter of getting it into my schedule, and that’s, you know, I get up on a Saturday morning and if I’ve been traveling during the week and I haven’t been able to get good physical activity, I make sure to get that’s number one on my priority list for the weekend.

Dr. Galson: It’s important for everyone, even people who have disabilities, kids who are young. Everyone can get physical activity in their own way, and it will help their health.

Joe: For more about the Physical Activity Guidelines for Americans, visit the website www.health.gov/PAguidelines.

Joe: Also, for more interviews and details about the Physical Activity Guidelines, tune into the NIH Research Radio podcast. Episode 77 from February 6 kicked off a three part series on the guidelines.

Host: And look for the April NIH News in Health newsletter for it’s cover feature on the Physical Activity Guidelines for Americans.

Now for our next feature, over the last decade, scientists have made an astonishing discovery: Nervous tissue can, to some degree, repair itself. Belle Waring brings us the story along with some remarkable video.

Belle: Disorders of the brain and nervous tissue affect all age groups and range from the normal aging process, to genetic disorders, to trauma, such as stroke and spinal cord injury. Dr. Dragan Maric of the National Institute of Neurological Disorders and Stroke explains that it’s difficult to study neurological disorders.

Maric: Well, it's true that the brain itself is a very complicated organ. Studying all the cells at the same time is very difficult, if not impossible, with our current technology. But if we can simplify this complexity into dissociating brain tissue into single cells, we can then get a much better resolution of these cells, and also use that information to isolate specific types of cells.

Belle: To understand how research could one day lead to new treatments, we’ll introduce you to a special kind of nerve cell that can produce other cells needed for normal functioning.

It’s called the immature progenitor cell and it has the unique ability to build brain tissue from a single cell. But getting access to these cells has been challenging because there are very few of them in the brain or elsewhere in nervous tissue.

Belle: Now Dr. Maric and his team have discovered how get these cells in a line, light them up and, using a computer-driven system, split them out.

Maric: Until recently there were really no good, viable strategies to isolate these cells; identify them, isolate them as pure populations so we can study them in an in vitro environment. This Fluorescent Activated Cell Sorting technology has provided an elegant and state-of-the-art solution to this problem. Fluorescent Activated Cell Sorting, or FACS, F-A-C-S, as we know it in short, is a sophisticated technique for analysis of different types of cells; not only analysis, but also isolating different types of cells based on their fluorescent properties and light-scattering properties.

Belle: Dr. Maric explains more about what can be seen with FACS technology.

Maric: Here you can actually see a cell is actually dividing, and over a period of five days you can see it generates many progeny, which were then identified by fluorescent microscopy.

And you can actually look at that one more time to see the beginning, which is at day one.

This is about day two, and over the period of five days you can see that one cell has actually generated almost like 20 cells here, and this is the end result where you can see we’ve generated some neurons which are color coded in red. Neurons are responsible for networking of the nervous tissue.

Belle: While the images are remarkable, Dr. Maric is focused on basic research.

Maric: Translating that to a clinical application for human patients obviously has to be done very carefully, very methodically, and we have to really be sure on a single cell level how to control these cells and not create bigger problems than we intend to.

I think the technology is advancing exponentially. We may be looking at another five, 10 or even 20 years, but we're making huge strides in trying to mitigate the problems that are associated with these neurological diseases. Eventually we will definitely strive for using these in routine clinical applications, in order to improve the quality of life of patients. These debilitative diseases can be very severe and the patients can suffer a lot. We want to help them out and alleviate these problems as soon as possible.

Belle: For more information, visit the website of the National Institute of Neurological Disorders and Stroke at www.ninds.nih.gov. Host: Thanks Belle. Now for our final report. NIH-funded scientists have found a more effective treatment for a common childhood eye problem, called convergence insufficiency, or CI. Dorie Hightower explains the muscle coordination problem and the new findings.

Dorie: For words on a page to appear in focus, a child’s eyes must turn inward, or converge.

In convergence insufficiency, or CI, the eyes do not converge easily, and as a result, additional muscular effort must be used to make the eyes turn in.

The National Eye Institute’s Dr. Brian Brooks explains that symptoms of CI include: loss of place, loss of concentration, reading slowly, eyestrain, headaches, blurry vision and double vision.

Dr. Brooks: Convergence insufficiency is relatively common and it can be quite frustrating for families to deal with, because very often they don’t understand and have been to multiple doctors before they come up with the correct diagnosis.

Dorie: Stephanie Bocek is a child diagnosed with CI disorder. Her mother explains the frustration they’ve faced.

Ms. Bocek: It took us a while to figure out what it was that was going on with her. We went to education specialists and you know we finally did go to ophthalmologist to find out that you know it was her vision that she was having trouble with.

Stephanie: I would feel like everyone in my class could read better than me and that every time that my teacher would call me to read like I would always get like scared like I was going to mess up or something and so I’d be scared every time we had to read out loud.

Dorie: While the majority of eye care professionals treat children diagnosed with CI using some form of home-based therapy, a new study concludes that office-based treatment by a trained therapist along with at-home reinforcement is more effective.

Dr. Scheiman: The important message from this study is that this common condition which affects about 5% of the school age population has an effective treatment. We now know that office based vision therapy can effectively treat about 75% of children with this eye muscle coordination problem.

Stephanie: About halfway through the vision therapy I, as I read, was already knowing that I was reading faster and I like wasn’t getting headaches and wasn’t having double vision and it was a little bit blurry but not as bad as it was and then I realized that it was really helping me.

Ms. Bocek: This time last year I would spend maybe six hours with Stephanie studying for a test. In the spring after she finished her vision therapy I would spend an hour with her. It made a very big difference in her ability to understand what was going on in the classroom, her ability to study, read, and her confidence.

Stephanie: I actually just recently finished a book in three days that was 247 pages and usually every night I would only read ten pages so that would take me a lot longer but I’m really proud of myself that I finished it in three days.

Dr. Brooks: This study showed that there are effective treatments for convergence insufficiency and that aggressive treatment is better than less aggressive treatment. The National Eye Institute is committed to continuing to study this disorder to understand whether the treatment effects are lasting and what are the best ways of handling this common condition.

If you think your child may have convergence insufficiency because he or she is seeing double when they’re working up close, or is having headaches frequently when they’re reading, I would suggest that they have a comprehensive eye examination by their local eye care professional, preferably a person who has a lot of experience working with children.

Dorie: To learn more about this study and CI, visit: www.nei.nih.gov. For I on NIH, this is Dorie Hightower.

Host: Thank you Dorie. And that’s it for another episode on I on NIH. If you’d like to see or forward individual segments from this program, they’re available on YouTube. Check out the NIHOD channel. There’s also many more NIH videos on the NIH4Health YouTube channel. For now, thanks for tuning in and please watch again next time. We’re working on stories about neural tube defects, teen drinking and much more. For I on NIH, I’m Joe Balintfy.

Narrator: "I on NIH" is a public service vodcast from the Department of Health and Human Servives. Produced by NIH News Media Branch, of the Office of the Director, Office of Communications and Public Liaison. Thanks for tuning in. We’ll be back again next month with another episode of "I on NIH."