Lasker Awards go to biologists for work on obesity, blindness

This morning, the Lasker Foundation announced its awards for biomedical research, prizes considered to be some of the most significant in the field. This year's prizes go to researchers who made significant strides in understanding the biology of obesity, and another who turned our knowledge of blood vessel development into a therapy for a degenerative eye disease. It's an interesting choice for the awards; the initial discoveries were indeed seminal, but they raised hopes for rapid medical progress that haven't quite panned out.

The Lasker Award for Clinical Research is going to Napoleone Ferrara who works at the biotech company Genentech (now a part of Roche). Ferrara could easily receive awards for his role in the discovery of VEGF (Vascular Endothelial Growth Factor), a protein that signals to the cells that line blood vessel walls. In response, these cells begin to divide and migrate, enabling the formation of new blood vessels.

Ferrara recognized that this process played a key role in age-related macular degeneration, where blood vessels in the retina grow in an uncontrolled manner, ultimately leading to severe reductions in vision. Ferrara helped develop a treatment for this by generating an antibody that neutralized VEGF by preventing it from interacting with its receptors. By eliminating a key signal for blood vessel growth, the vision of many patients facing macular degeneration can be preserved.

Two aspects of this approach are pretty notable. The use of an antibody for targeted therapeutic work has been considered for decades prior to Ferrera's work, but very few treatments of this sort had ever reached the market. In recent years, a number of other similar treatments have arrived, many of them targeting cancer-promoting proteins. They're effective to a degree, but none of them have been outright cures, and most come with far more side effects than the specificity of antibodies might have led many to suspect.

In fact, VEGF antibodies were originally developed as a therapy for solid tumors, which require the growth of new blood vessels to keep the cancerous cells supplied with nutrients—Genentech sells one of these, and Ferrara played a central role in its creation. But, again, this approach hasn't quite been everything it was hoped it would be, as the treatment is only partially effective in combination with other therapies, and its high costs have caused a number of national and private healthcare providers to drop it as a treatment option. This may explain why the prize citation primarily focuses on the more clearly effective macular degeneration treatment.

Obesity and genetics

The Medical Research award went to Douglas Coleman and Jeffrey Friedman for their work, which led to the discovery of one of the first hormones linked to obesity, leptin. Coleman is based at the world's foremost mouse-breeding site, Jackson Labs, and benefitted from the fact that its staff is trained to identify unusual looking mice that sometimes arise spontaneously within the breeding stocks. Over the years, two different lines of mice were discovered that had an inherited form of obesity.

The award citation notes that Coleman demonstrated that one of the two genes involved was a circulating hormone through an amazing experiment: he linked the two circulatory systems of the mice together, and showed that one of them produced a soluble factor that could rescue the phenotype in the other, but remained obese itself. Friedman eventually isolated the gene for this factor, called ob for the obese phenotype; the protein that it produces has since been termed leptin.

Leptin is now known to be produced by fat cells, and signal to areas of the brain that influence food intake. Animals lacking either leptin or its receptors never experience satiation, and continue eating long after filling their dietary needs. A few humans with mutations in the leptin gene have since been identified; they are also obese.

Again, this was an area that seemed very promising. Other hormones that influence appetite were identified later, raising the hope that obesity might be controlled by a careful suppression of appetite that used the body's own natural mechanisms for doing so. But that hasn't quite worked out either; even using leptin to block the obesity of the people with mutant forms of it hasn't turned out to be easy. Ultimately, a better understanding of how the body decides when and how much to eat may help cut into the high obesity levels, but that still seems to be a few years off.

The Laskers act as recognition that, even though these discoveries may not have worked out as many people had hoped, they have fundamentally changed how we view two very significant problems (obesity and cancer) and, in one case, led to an effective treatment for an unrelated disease.

Via : arstechnica.com

Pregnant Women Should Gain Less Weight (Easy For You To Say, New York Times)

In her Personal Health column in the New York Times, Jane Brody, took on the increasingly pressing issue of pregnancy weight gain. Recent studies have revealed that the more a woman gains in pregnancy, the more likely she is to have a big baby. And big babies are more likely to have health problems, including complications at birth, and weight problems later in life.

There are more big babies being born now than ever before. And per this and other studies, women are both gaining more weight during pregnancy and starting out heavier when they get pregnant. Brody says this study may show we’ve got the wrong idea about what’s causing our obesity epidemic. What if it isn’t the result of poor eating habits and low activity levels? What if it isn’t about behavioral choices at all, but the result of excessive weight gain in pregnancy?

This study has been out for a bit (I wrote about it a few weeks ago). But Brody’s piece drove it home in a big way. If birth weight is truly a predictor of future body mass index (a connection I was unaware of before reading this piece) and pregnancy weight gain is a predictor of birth weight, well, it seems like the case for keeping moms’ weight down might be even stronger than we’d previously thought.

And the numbers are indeed concerning: “fewer than 40 percent of pregnant women gain only the recommended amount of weight during their pregnancy,” according to Dr. Sylvia R. Karasu and Dr. T. Byram Karasu, authors of “The Gravity of Weight.”

So what does this mean for pregnant women, now and in the future? I think it’s pretty clear that we are going to start seeing stricter guidelines about pregnancy diet and weight gain. While I see that there is good reason for this from a public health perspective, I worry about how this translates to the individual woman. Pregnancy is already so rife with restrictions and recommendations. A certain looseness about the quantity of food one eats can sort of help compensate for the fact that so many foods and drinks are off limits. If pregnancy became a time of tight diets and morbid fear of excessive weight gain…it would be sort of like the rest of most women’s lives.

Pregnancy weight gain is not always so easy to control. Food cravings can rule the appetite, and exercise can be more of a challenge than usual. In fact, pregnancy weight and diet control may just be part of the puzzle. The take-home from these findings, according to study leader Janet Currie, is not just about pregnancy weight. It’s about womens’ weight in general: “The next frontier has to be the prepregnancy period. If we really want to improve the health of children, we have to get to mothers before they get pregnant.” So if you’re thinking of having children sometime in the future, expect to have your diet and exercise plan be part of the discussion.

Via : blogs.babble.com

Sunless tanning: Teens learn benefits

Sunless tanning lotions are growing in popularity among teens and could encourage sun safety, according to a new study.

Researchers at the American Cancer Society in Atlanta say about one in every ten teens use sunless tanning products. However, these adolescents were also more likely to frequent tanning beds, not wear sunscreen and get more sunburns.

When researchers at the University of Massachusetts educated a group of sunbathers on the dangers of UV exposure, as well as the benefits of sunless tanning products, their habits changed. Two months later, participants said they sunbathed less often and had fewer sunburns. They also used sunless tanning products more often.

Researchers say promoting these products as a part of a health message, rather than just for cosmetic purposes, could have an important impact on skin cancer.

Sunless tanners up skin cancer risk

Despite the increase reported in the use of sunless tanning products, teenagers still get sunburns and engage in other skin-damaging behaviors such as indoor tanning.


"Many people find a tanned appearance to be physically attractive and combating that with a health message is difficult," said study co-author Sherry Pagoto of the University of Massachusetts Medical School in Worchester.

Previous studies, however, have linked too much sun ultraviolet radiation with melanoma, the deadliest type of skin cancer and the second leading cause of malignancy among young women.

According to the study published in the Archives of Dermatology, the higher use of sunless tanning products does not necessarily mean using more sunscreen or limiting the UV exposure.

"Our findings are that in adolescents, use of sunless tanning products appears independently correlated with risky UVR exposure behaviors [indoor tanning and having sunburns in the previous summer] but not with routine use of sunscreen," said lead researcher Vilma E. Cokkinides of the American Cancer Society.

"People who really want to be tan should strongly consider using sunless tanning instead of tanning booths or sunbathing," said Pagoto, stressing that having a fake tan instead of sunbathing can lower the women's risk of developing skin malignancies.

Scientists believe offering sunbathing women with free samples of tanning lotion and sunscreen can not only improve their awareness about the harms of sun exposure but also can protect them against the related malignancies.

"Instead of trying to talk people out of wanting to be tan, we decided to encourage them to use sunless tanning as a healthier alternative," Pagoto added.

Most sunless tanning lotions and sprays contain a chemical called dihydroxyacetone, a compound approved by the US Food and Drug Administration which combines with amino acids in the skin to produce a tanned color.

Via : presstv.ir

IV Aspirin Found to Be Safe, Effective in Severe Headache

Intravenous (IV) aspirin appears to be effective and safe in the treatment of patients hospitalized for the management of severe headache, according to research published in the Sept. 21 issue of Neurology.

Mark W. Weatherall, Ph.D., of the National Hospital for Neurology and Neurosurgery in London, and colleagues reviewed the records of 168 severe headache patients who received IV aspirin (lysine acetylsalicylic acid), most of whom had overused and were withdrawing from other pain medications.

The researchers found that, on more than a quarter of the occasions on which IV aspirin was administered, there was at least a three-point decrease on a 10-point visual analog pain scale. There was an overall adverse effect rate of 5.9 percent, with no serious adverse events reported. Two patients discontinued aspirin treatment: one asthma patient who had a decrease in vital capacity and a second patient who became needle phobic. The most common adverse events were nausea and cannula pain, experienced by four and three patients, respectively.

"In summary, IV lysine acetylsalicylic acid (aspirin) is effective and well-tolerated in the management of severe rebound headache in patients undergoing medication withdrawal," the authors write.

Several authors disclosed financial ties to pharmaceutical and/or medical device companies. One author estimates that 5 percent of his practice involves administering IV aspirin to headache patients.

Via : modernmedicine.com

A New Campaign to Fight Lung Cancer Gets £100,000

With aim of combating lung cancer, as much as £100,000 amount has been granted to South Lakeland.

NHS Cumbria is ready to come up with a new campaign, aiming to alert people about the early signs of lung cancer and convincing them to go for check up with their doctors.

The Department of Health has awarded the money to this noteworthy campaign, which will come into action in January. The NHS North East Cancer Network has also given £25,000 to support the campaign.

The last recorded figures of cancer deaths were revealed in 2007, according to the data, lung cancer killed 321 people in Cumbria.

Lung cancer falls into the category of most serious and common form of cancer. Coughing persistently for several weeks, chest pain, sudden weight loss and shortness of breath are some of the common symptoms of lung cancer.

Most of the people have lung cancer because of smoking as this habit is the biggest reason of developing this serious type of cancer. It has been estimated that smoking 20 cigarettes in a day results in increasing the chances of developing lung cancer by 20 times, as compared to the ones who do not smoke.

Via : topnews.co.uk

New Method Helps Separation of DNA Fragments in Hydrogels

A Texas A&M University chemical engineer has provided an important advancement to DNA analysis by revealing a new method of separating DNA fragments more effectively, which has the potential to benefit the fields of genetic engineering, biomedical research and forensics.

Victor M. Ugaz, an associate professor in the university's Artie McFerrin Department of Chemical Engineering, along with Nan Shi, a graduate student, have been working with a gelatin called hydrogel in order to develop and observe the certain types of conditions that "result in the optimum gel pore structure for separation of a wide range of DNA fragment sizes." The way DNA fragments moved through the hydrogel was key to their findings.

Ugaz and Shi's research consisted of using a process called electrophoresis, where negatively charged DNA is inserted into a porous hydrogel. Then, an electric field is applied in order to make DNA fragments move though the hydrogel's pores. Smaller chains are able to move through pores easier and faster, where longer chains have to "unthread" and separate in order to pass through pores that are either the same size or smaller than the coiled DNA fragment. This separation process is called entropic trapping. Longer DNA chains separate and squeeze quickly through smaller pores and return to its coiled shape in larger pores.

"It changes the way you think about the entire process because these findings demonstrate a rational way to connect the pore structure of the gel quantitatively to the mechanism by which the DNA moves through the gel," said Ugaz. "Researchers can now actually design gels to specifically harness certain effects, and they will need this information we have found to do that."

What makes Ugaz and Shi's work an important advancement is the use of entropic trapping for separation within a hydrogel because up until this point, scientists were unsure as to how the DNA fragment's transport system was linked to the hydrogel's structure of pores. Choosing the correct hydrogel for these types of processes was difficult because hydrogels have specific properties, and there was no way of knowing which hydrogel possessed the right properties for this type of research. But entropic trapping within the gel has proved to be an efficient way for DNA fragments to travel through the pores.

"You want to be able to detect the smallest possible difference in size between DNA fragments," said Ugaz. "The size of the fragments may be very close, and you may need to detect a difference of one unit in size. To do this, you would want to be able to specifically construct a hydrogel with the necessary pore structure to achieve this.

"We have a better picture of how to do this than what has existed. We know what the gel needs to look like and how it needs to be prepared. We're able to understand how to construct a gel that would allow DNA to move via an entropic trapping method that enhances separation performance and in turn leads to more effective analysis. This finding could have enormous implications by helping remove current barriers to separation efficiency."

Via : dailytech.com