Category Archives: Health Care

2009 Nobel Prize in Physiology or Medicine

This year’s Nobel Prize in Physiology or Medicine is awarded to three scientists who have solved a major problem in biology: how the chromosomes can be copied in a complete way during cell divisions and how they are protected against degradation. The Nobel Laureates have shown that the solution is to be found in the ends of the chromosomes – the telomeres – and in an enzyme that forms them – telomerase.

The long, thread-like DNA molecules that carry our genes are packed into chromosomes, the telomeres being the caps on their ends. Elizabeth Blackburn and Jack Szostak discovered that a unique DNA sequence in the telomeres protects the chromosomes from degradation. Carol Greider and Elizabeth Blackburn identified telomerase, the enzyme that makes telomere DNA. These discoveries explained how the ends of the chromosomes are protected by the telomeres and that they are built by telomerase.

If the telomeres are shortened, cells age. Conversely, if telomerase activity is high, telomere length is maintained, and cellular senescence is delayed. This is the case in cancer cells, which can be considered to have eternal life. Certain inherited diseases, in contrast, are characterized by a defective telomerase, resulting in damaged cells. The award of the Nobel Prize recognizes the discovery of a fundamental mechanism in the cell, a discovery that has stimulated the development of new therapeutic strategies.

Scientists began to investigate what roles the telomere might play in the cell. Szostak’s group identified yeast cells with mutations that led to a gradual shortening of the telomeres. Such cells grew poorly and eventually stopped dividing. Blackburn and her co-workers made mutations in the RNA of the telomerase and observed similar effects in Tetrahymena. In both cases, this led to premature cellular ageing – senescence. In contrast, functional telomeres instead prevent chromosomal damage and delay cellular senescence. Later on, Greider’s group showed that the senescence of human cells is also delayed by telomerase. Research in this area has been intense and it is now known that the DNA sequence in the telomere attracts proteins that form a protective cap around the fragile ends of the DNA strands.

Many scientists speculated that telomere shortening could be the reason for ageing, not only in the individual cells but also in the organism as a whole. But the ageing process has turned out to be complex and it is now thought to depend on several different factors, the telomere being one of them. Research in this area remains intense.

The 3 awardees are citizens of the USA; two were born elsewhere.
Read more about their research at the Nobel Prize web site.

Molecular biologist Elizabeth Blackburn–one of Time magazine’s 100 “Most Influential People in the World” in 2007–made headlines in 2004 when she was dismissed from the President’s Council on Bioethics after objecting to the council’s call for a moratorium on stem cell research and protesting the suppression of relevant scientific evidence in its final report.

Webcast of Dr. Elizabeth Blackburn speaking at Google:
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Bacteria Use Nitric Oxide to Resist Antibiotics

Scientists Discover Mechanism to Make Existing Antibiotics More Effective at Lower Doses

Eliminating this NO[nitric oxide]-mediated bacterial defense renders existing antibiotics more potent at lower, less toxic, doses. With infectious diseases the major cause of death worldwide, the study paves the way for new ways of combating bacteria that have become antibiotic resistant.

NO is a small molecule composed of one atom of oxygen and one of nitrogen. It was known as a toxic gas and air pollutant until 1987, when it was first shown to play a physiological role in mammals, for which a Nobel Prize was later awarded. NO has since been found to take part in an extraordinary range of activities including learning and memory, blood pressure regulation, penile erection, digestion and the fighting of infection and cancer. A few years ago, the Nudler’s group from NYU demonstrated that bacteria mobilize NO to defend against the oxidative stress. The new study from the same group supports the radical idea that many antibiotics cause the oxidative stress in bacteria, often resulting in their death, whereas NO counters this effect. This work suggests scientists could use commercially available inhibitors of NO-synthase, an enzyme producing NO in bacteria and humans, to make antibiotic resistant bacteria like MRSA and ANTHRAX more sensitive to available drugs during acute infection.
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The study by Nudler and his colleagues was funded by a 2006 Pioneer Award from the National Institutes of Health in Bethesda, Maryland. The Pioneer Award, a $2.5 million grant over five years, is designed to support individual scientists of exceptional creativity who propose pioneering and possibly transforming approaches to major challenges in biomedical and behavioral research.

Smokers with High Blood Pressure and High Cholesterol Lose 10 Years

By examining data from the Whitehall Study researchers have found smokers with high blood pressure and high cholesterol in middle age died 10 years earlier than the others after reaching age 50. This is independent of changes after later in life (quiting smoking, etc.). Life expectancy in relation to cardiovascular risk factors: 38 year follow-up of 19,000 men in the Whitehall study

At entry, 42% of the men were current smokers, 39% had high blood pressure, and 51% had high cholesterol. At the re-examination, about two thirds of the previously “current” smokers had quit smoking shortly after entry and the mean differences in levels of those with high and low levels of blood pressure and cholesterol were attenuated by two thirds. Compared with men without any baseline risk factors, the presence of all three risk factors at entry was associated with a 10 year shorter life expectancy from age 50 (23.7 v 33.3 years). Compared with men in the lowest 5% of a risk score based on smoking, diabetes, employment grade, and continuous levels of blood pressure, cholesterol concentration, and body mass index (BMI), men in the highest 5% had a 15 year shorter life expectancy from age 50 (20.2 v 35.4 years).

Conclusion Despite substantial changes in these risk factors over time, baseline differences in risk factors were associated with 10 to 15 year shorter life expectancy from age 50.

Another conclusion: if you don’t want to live a shorter life, don’t smoke. Not a new idea but given how many people continue to smoke it seems some don’t understand this conclusion.

How to Stay Healthy: Avoiding the Flu

It is no secret that washing your hands is a great strategy to stay healthy. Still few people take care to wash their hands thoroughly frequently during each day. The H1N1 Flu is just the latest sickness that washing your hands protects you from.

The CDC recommends you take these everyday steps to protect your health to protect yourself from the flu:

Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hand cleaners are also effective. Though the scientific evidence is not as extensive as that on hand washing and alcohol-based sanitizers, other hand sanitizers that do not contain alcohol may be useful for killing flu germs on hands.
Avoid touching your eyes, nose or mouth. Germs spread this way.
Try to avoid close contact with sick people.

And to keep others healthy you should

Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it. [others also suggest coughing into you elbow instead of your hands, again to reduce the spread of germs.]
If you are sick with flu-like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.) Keep away from others as much as possible to keep from making others sick.

The spread of this 2009 H1N1 flu is thought to be happening in the same way that seasonal flu spreads. Flu viruses are spread mainly from person to person through coughing or sneezing of people with influenza. Sometimes people may become infected by touching something with flu viruses on it and then touching their mouth or nose.

The incidence of H1N1flu is likely to be high this flu season based on results in the Southern Hemishpere. Symptoms are those of the flu: fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue; can include diarrhea and vomiting.

The CDC includes weekly flu statistics on their web site. Since mid-April to August 30, 2009, a total of 9,079 hospitalizations and 593 deaths associated with 2009 influenza A (H1N1) viruses have been reported to CDC an increase from 8,843 hospitalizations and 556 deaths from the prior week.

Engineer Tried to Save His Sister and Invented a Breakthrough Medical Device

Here is another remarkable example of the great benefit engineers provide society.

How a software engineer tried to save his sister and invented a breakthrough medical device

I wanted to help my sister as much as I could. I went to Medline, where there are hundreds of thousands of documents describing clinical studies, to see what I could find.

There are billions of dollars spent every year on clinical studies. I was surprised to discover that there were sometimes clinical studies of treatments for which there were no clinical applications. The trials would show successful results but no clinical applications.

I found a 1987 Italian funded set of clinical studies that showed successful treatment of tumors by the application of chemotherapy directly into the tumors. But I could find nothing since then.
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It took us two years to do the engineering. And it has taken the FDA seven years and two months to approve the product for sale. We were able to shorten the FDA process a little by saying that it was similar to other devices that had already been approved.

Great stuff.

Scientific Illiteracy Leaves Many at Risk in Making Health Care Judgements

Scientific literacy is important for many reasons and that importance has increased greatly over the last century. Medical research is often difficult to interpret. Often various studies seem to contradict each other. Often the conclusions that are drawn are far too broad (especially as the research conclusions are passed on and people hear of them overly simplified ways).

Many health care options are not obviously all good, or all bad, but instead a mix of benefits and risks, both of which include interactions with the individuals makeup. So we often see contradictory (and seemingly contradictory) advice. Without a level of scientific literacy it is very difficult for people to know how to react to medical advice.

We have numerous posts on the scientific inquiry process showing that acquiring scientific knowledge is complex and can be quite confusing in many instances. While understanding things are often less clear cut than they are presented it is still true that most often strategies for healthy living have far better practices that will provide far better results than alternatives.

The scientific illiteracy that has some think because their are risks no matter what is done that means there is no evidence some alternatives are far superior is very dangerous. As you can see in action now with those that risk their and others lives and health by doing things like not vaccinating their children, or driving when drunk, or driving when talking on a cell phone.

Without a scientifically literate society even completely obvious measures like not using antibiotics on viral infections are ignored.

The Calorie Delusion

The calorie delusion: Why food labels are wrong

Nutritionists are well aware that our bodies don’t incinerate food, they digest it. And digestion – from chewing food to moving it through the gut and chemically breaking it down along the way – takes a different amount of energy for different foods. According to Geoffrey Livesey, an independent nutritionist based in Norfolk, UK, this can lower the number of calories your body extracts from a meal by anywhere between 5 and 25 per cent depending on the food eaten.
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Dietary fibre is one example. As well as being more resistant to mechanical and chemical digestion than other forms of carbohydrate, dietary fibre provides energy for gut microbes, and they take their cut before we get our share. Livesey has calculated that all these factors reduce the energy derived from dietary fibre by 25 per cent
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“Cooking gives food energy,” says Wrangham. It alters the structure of the food at the molecular level, making it easier for our body to break it up and extract the nutrients.

In plants, for example, much of the energy from starch is stored as amylopectin, which is semi-crystalline, does not dissolve in water, and cannot be easily digested. Heat starchy foods with water, though, and the crystalline forms begin to melt. The starch granules absorb water, swell, and eventually burst. The amylopectin is shattered into short starch molecules called amylose, which are easily digested by the enzyme amylase.

It seems pretty obvious, just looking around, as you walk around in any city that people are much fatter, on average, than we were 20 years ago. And the data shows people were much larger (taller, but also fatter) 20 years ago than they were 100 years ago. And we know obesity causes many human health issues. The failure to address the obesity problem in the USA is another example of the failed “health care” system. Instead of a working health care system we just manage diseases that result for unhealthy living. We should be do better at providing information to people on healthy eating (including more accurate calorie counts as it concerns food we eat) and healthy lifestyle choices.

Teen diagnoses her own disease in science class

Her doctors, no matter how hard they tried, couldn’t figure out the cause of Jessica’s abdominal distress. Then one day in January, Terry, 18, figured it out on her own.

In her Advanced Placement high school science class, she was looking under the microscope at slides of her own intestinal tissue — slides her pathologist had said were completely normal — and spotted an area of inflamed tissue called a granuloma, a clear indication that she had Crohn’s disease.

“It’s weird I had to solve my own medical problem,” Terry told CNN affiliate KOMO in Seattle, Washington. “There were just no answers anywhere. … I was always sick.”
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Crohn’s disease is often misdiagnosed or diagnosed very late, says Dr. Corey Siegel, director of the Inflammatory Bowel Disease Center at Dartmouth-Hitchcock Medical Center in Lebanon, New Hampshire. “Granulomas are oftentimes very hard to find and not always even present at all,” Siegel said. “I commend Jessica for her meticulous work.”

Waste Treatment Plants Result in Super Bacteria

Multiple antibiotic-resistant bacteria has emerged as one of the top public health issues worldwide in the last few decades as the overuse of antibiotics and other factors have caused bacteria to become resistant to common drugs. Chuanwu Xi‘s group chose to study Acinetobacter because it is a growing cause of hospital-acquired infections and because of its ability to acquire antibiotic resistance.

Xi said the problem isn’t that treatment plants don’t do a good job of cleaning the water—it’s that they simply aren’t equipped to remove all antibiotics and other pharmaceuticals entering the treatment plants.

The treatment process is fertile ground for the creation of superbugs because it encourages bacteria to grow and break down the organic matter. However, the good bacteria grow and replicate along with the bad. In the confined space, bacteria share resistant genetic materials, and remaining antibiotics and other stressors may select multi-drug resistant bacteria.

While scientists learn more about so-called superbugs, patients can do their part by not insisting on antibiotics for ailments that antibiotics don’t treat, such as a common cold or the flu, Xi said. Also, instead of flushing unused drugs, they should be saved and disposed of at designated collection sites so they don’t enter the sewer system.

The next step, said Xi, is to see how far downstream the superbugs survive and try to understand the link between aquatic and human superbugs. This study did not look past 100 yards.

Xi’s colleagues include visiting scholar Yongli Zhang; Carl Marrs, associate professor of public health; and Carl Simon, professor of mathematics.

Xi and colleagues found that while the total number of bacteria left in the final discharge effluent declined dramatically after treatment, the remaining bacteria was significantly more likely to resist multiple antibiotics than bacteria in water samples upstream. Some strains resisted as many as seven of eight antibiotics tested. The bacteria in samples taken 100 yards downstream also were more likely to resist multiple drugs than bacteria upstream.

Full press release

Antigen Shift in Influenza Viruses

Antigenic shift is the process by which at least two different strains of a virus, (or different viruses), especially influenza, combine to form a new subtype having a mixture of the surface antigens of the two original strains.

Pigs can be infected with human, avian and swine influenza viruses. Because pigs are susceptible to all three they can be a breeding ground for antigenic shift (as in the recent case of H1N1 Flu – Swine Flu) allowing viruses to mix and create a new virus.

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