Category Archives: Research

A single spot in the Sahara that provides huge amounts of nutrients to the Amazon

The BodÃ©lÃ© depression: a single spot in the Sahara that provides most of the mineral dust to the Amazon forest

About 40 million tons of dust are transported annually from the Sahara to the Amazon basin. Saharan dust has been proposed to be the main mineral source that fertilizes the Amazon basin, generating a dependence of the health and productivity of the rain forest on dust supply from the Sahara. Here we show that about half of the annual dust supply to the Amazon basin is emitted from a single source: the BodÃ©lÃ© depression located northeast of Lake Chad, approximately 0.5% of the size of the Amazon or 0.2% of the Sahara. Placed in a narrow path between two mountain chains that direct and accelerate the surface winds over the depression, the BodÃ©lÃ© emits dust on 40% of the winter days, averaging more than 0.7 million tons of dust per day.

Even understanding how connected the global ecosystem is, research like this provides amazing reminders of those connections.

Domestic Cats Remain Successful Predators

House cats kill more critters than thought by Elizabeth Weise

While only 30% of roaming house cats kill prey — two animals a week on average — they are still slaying more wildlife than previously believed, according to research from the University of Georgia.
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The cats brought home just under a quarter of what they killed, ate 30% and left 49% to rot where they died.

The carnage cuts across species. Lizards, snakes and frogs made up 41% of the animals killed, Loyd and fellow researcher Sonia Hernandez found. Mammals such as chipmunks and voles were 25%, insects and worms 20% and birds 12%.
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Seeking a window into the hidden lives of cats, the researchers recruited 60 owners in the Athens, Ga., area. Each owner put a small video camera mounted on a break-away collar on the cat in the morning and let the cat out, then removed the camera and downloaded the footage each night.

Interesting data. As I wrote about before you can get your very own cat cam and see what your cat is up to. I posted an interview I did with the engineer that designs and sells the cat cams.

Virus Kills Breast Cancer Cells in Laboratory

Some very exciting and good news from Penn State. Researchers have found a virus that kills breast cancer cells. It is great to read about research breakthroughs like this. Of course, most of these announcements never become practical solutions, unfortunately. And if they do it is many many years later and almost always in much less exciting ways than the headlines. Still, the percentage that do make it through the process into workable solutions provide us great benefits.

Virus kills breast cancer cells in laboratory

Adeno-associated virus type 2 (AAV2) is a virus that regularly infects humans but causes no disease. Past studies by the same researchers show that it promotes tumor cell death in cervical cancer cells infected with human papillomavirus. Researchers used an unaltered, naturally occurring version of AAV2 on human breast cancer cells.

“Breast cancer is the most prevalent cancer in the world and is the leading cause of cancer-related death in women,” said Samina Alam, research associate in microbiology and immunology. “It is also complex to treat.”
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“We can see the virus is killing the cancer cells, but how is it doing it?” Alam said. “If we can determine which viral genes are being used, we may be able to introduce those genes into a therapeutic. If we can determine which pathways the virus is triggering, we can then screen new drugs that target those pathways. Or we may simply be able to use the virus itself.”
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AAV2 does not affect healthy cells. However, if AAV2 were used in humans, the potential exists that the body’s immune system would fight to remove it from the body. Therefore, by learning how AAV2 targets the death pathways, researchers potentially can find ways to treat the cancer without using the actual virus.

In ongoing studies, the Penn State researchers also have shown AAV2 can kill cells derived from prostate cancer, mesothelioma, squamous cell carcinoma, and melanoma. A fourth line of breast cancer cells — representing the most aggressive form of the disease — also was studied in a mouse breast tumor model, followed by treatment with AAV2. Preliminary results show the destruction of the tumors in the mice, and researchers will report the findings of those mouse studies soon.

The fight against cancer has many promising breakthroughs. We have made some great progress. Still the fight is extremely difficult and we have many more frustrations than successes.

Physical Activity for Adults: Inactivity Leads to 5.3 Million Early Deaths a Year

Obviously health care doesn’t only mean sickness treatment. Avoiding sickness is much better than treating it. Sadly we spend far too little energy on creating health and far too much on treating sickness.

Physical activity guidelines for adults (follow link for more details and guidelines for others) from the UK National Health Service

To stay healthy, adults aged 19-64 should try to be active daily and should do:

At least 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity such as cycling or fast walking every week, or
75 minutes (1 hour and 15 minutes) of vigorous-intensity aerobic activity such as running or a game of singles tennis every week
and muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders and arms).

Sedentary lifestyle can kill

one in three adults worldwide fails to do the recommended 150 minutes of moderate aerobic physical activity per week. In the UK two out of three adults don’t manage it.

So rather than stressing the health benefits of exercise, the Lancet researchers have opted to show the harm caused by inactivity. They estimate lack of exercise is responsible for about 5.3m deaths a year – about the same number as smoking.

This is based on estimates of the impact on inactivity on coronary heart disease, Type 2 diabetes, and two specfic cancers – breast and bowel – where lack of exercise is a major risk factor.

Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancy

Worldwide, we estimate that physical inactivity causes 6% (ranging from 3Â·2% in southeast Asia to 7Â·8% in the eastern Mediterranean region) of the burden of disease from coronary heart disease, 7% (3Â·9—9Â·6) of type 2 diabetes, 10% (5Â·6—14Â·1) of breast cancer, and 10% (5Â·7—13Â·8) of colon cancer. Inactivity causes 9% (range 5Â·1—12Â·5) of premature mortality, or more than 5Â·3 million of the 57 million deaths that occurred worldwide in 2008. If inactivity were not eliminated, but decreased instead by 10% or 25%, more than 533 000 and more than 1Â·3 million deaths, respectively, could be averted every year. We estimated that elimination of physical inactivity would increase the life expectancy of the world’s population by 0Â·68 (range 0Â·41—0Â·95) years.

An Apple a Day is Good Advice

Apples really are healthy food. They provide fiber and nutrients without a large amount of calories. Including them in your diet can contribute to a healthy lifestyle.

How apples can make you skinnier & 4 more health benefits of apples

Packing in quite a bit of soluble fiber (4 grams per medium apple) for a modest amount of calories (95) makes apples a filling, sweet snack. Plus, a medium apple counts as 1 cup of fruit, so after eating one you’re well on your way to meeting your daily fruit quota (around 2 cups for adults on a 2,000-calorie diet). They also are a good source of immune-boosting vitamin C (providing 14% of the Daily Value).
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a survey of eating and health habits, found that people who had eaten apples in any form over the past day were 27 percent less likely to have symptoms of metabolic syndrome than those who didn’t. The apple eaters also had lower levels of C-reactive protein, a marker of inflammation whose presence in the blood suggests an increased risk for heart disease and diabetes.

“Our study suggests that ursolic acid increases skeletal muscle and brown fat leading to increased calorie burning, which in turn protects against diet-induced obesity, pre-diabetes and fatty liver disease,” Christopher Adams, M.D., Ph.D., UI associate professor of internal medicine at the University of Iowa.

Until quite recently, researchers believed that only infants had brown fat, which then disappeared during childhood. However, improved imaging techniques have shown that adults do retain a very small amount of the substance mostly in the neck and between the shoulder blades. Some studies have linked increased levels of brown fat with lower levels of obesity and healthier levels of blood sugar and blood lipid, leading to the suggestion that brown fat may be helpful in preventing obesity and diabetes.

Using Robots to Collect Data on our Oceans

Interesting idea to use self propelled robots to provide data on the oceans. They use no fuel to move, they use wave energy. They also have solar panels on the top. The wave gliders can travel to a distant area, collect data, and return to base. One of the big problems with convention methods of collecting data on the oceans is the large costs of placing the buoys (and the cost of servicing them).

One Scientists 20 Year Effort to Defeat Dengue Fever

As I have said many times scientific breakthroughs often follow many years of effort. Here is a great example of a scientist putting in great work for years and it looks like it is about to payoff for hundreds of millions of people.

A Scientist’s 20-Year Quest To Defeat Dengue Fever

Now as I said, Scott’s been pushing this idea of using Wolbachia to control dengue for decades, for a most of that time without any success. I asked Scott what it takes to stick with something for that long.

“I think being obsessive,” he replied. “Being maybe a little ill in that regard. And it’s just that I seem to have focused my obsession onto Wolbachia instead of on to postage stamps or model trains.”

And even though his obsession has brought him to the point where he’s shown he can get his Wolbachia-infected mosquitoes to spread in the wild, that’s not the success he’s ultimately after. “Success for me is having a significant impact on dengue disease in communities,” he says.

To do that, he’ll have to release his mosquitoes in a place where there’s a lot of dengue, and then see if that brings down the number of cases of the disease in humans. Those studies are being planned now.

The stakes are high. By some estimates, more than a billion people around the world are at risk for getting dengue. Even if it doesn’t kill you, I’m told a case of dengue can make you feel so bad, wish you were dead.
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But Scott says it’s not yet time to celebrate.

“We’ve got some good preliminary data, and we’re on the path. And it’s looking good. But you know I am a realist. It could fall over at any day,” says Scott.

Prostate Cancer Drug so Effective Trial Stopped to Give Drug to All Participants

Prostate cancer drug so effective trial stopped by Victoria Colliver

The hormone treatment, Johnson & Johnson’s Zytiga, when added to a standard steroid therapy doubled the time it takes for the disease to progress in patients treated with the standard therapy alone, said the lead researcher, Dr. Charles Ryan, associate professor of clinical medicine at the UCSF Helen Diller Family Comprehensive Cancer Center.

The U.S. Food and Drug Administration last year approved Zytiga, also known as abiraterone, for use in men whose prostate cancer had spread to other parts of their body and had already been treated with chemotherapy.
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This trial focused on patients whose cancer had metastasized, may have been treated with other hormone therapies but had not yet gone through chemotherapy.
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Prostate cancer, the second most common form of cancer in males after only lung cancer, is diagnosed in about 200,000 men in the United States each year. And while it is generally treatable, the disease kills nearly 30,000 men a year.

Because their disease is often slow-growing, about a third of patients diagnosed with prostate cancer won’t be treated. Another third will undergo successful treatment, which could include surgery, various hormone therapies or chemotherapy.

Still, a third of patients will have recurrent or aggressive disease that may have been caught too late. Ryan said men tend to die when the cancer spreads outside the prostate, mostly to bone, and the patient becomes resistant to hormonal therapy. The cancer cells rely on testosterone to exist, so typically doctors treat patients with testosterone-blocking hormone therapy.

But patients become resistant when the cancer cells develop the ability to make their own hormone and learn to survive even in the face of the testosterone-blocking drugs, giving the disease the ability to progress, Ryan said.

Zytiga is the first FDA-approved drug that can go inside the cancer cell and block it from making its own testosterone.

The trial involved 1,088 men who were being treated by 151 cancer centers in 12 countries. Each was given a low dose of the steroid prednisone, which works to combat the cancer

This is very good news. There is lots of positive news over the years. Often it seems to come to nothing years later. Promising drugs in the lab turn out to be far less promising in clinical trail. But very successful clinical trials are very good news. Even this kind of news though really should be confirmed by larger scale success, but this is a very good start.

Scientific Inquiry Process Finds More Evidence Supporting Einstein’s Theory

As scientists have been able to see farther and deeper into the universe, the laws that govern its expansion have been revealed to be under the influence of an unexplained force.

In a paper on the arXiv, Astrophysical Tests of Modified Gravity: Constraints from Distance Indicators in the Nearby Universe, are a vindication of Einstein’s theory of gravity. Having survived several decades of tests in the solar system, it has passed this new test in galaxies beyond our own as well.

In 1998, astrophysicists made an observation that turned gravity on its ear: the universe’s rate of expansion is speeding up. If gravity acts the same everywhere, stars and galaxies propelled outward by the Big Bang should continuously slow down, like objects thrown from an explosion do here on Earth.

This observation used distant supernovae to show that the expansion of the universe was speeding up rather than slowing down. This indicated that something was missing from physicists’ understanding of how the universe responds to gravity, which is described by Einstein’s theory of general relativity. Two branches of theories have sprung up, each trying to fill its gaps in a different way.

One branch — dark energy — suggests that the vacuum of space has an energy associated with it and that energy causes the observed acceleration. The other falls under the umbrella of “scalar-tensor” gravity theories, which effectively posits a fifth force (beyond gravity, electromagnetism and the strong and weak nuclear forces) that alters gravity on cosmologically large scales.

“These two possibilities are both radical in their own way,” University of Pennsylvania astrophysicist Bhuvnesh Jain said. “One is saying that general relativity is correct, but we have this strange new form of energy. The other is saying we don’t have a new form of energy, but gravity is not described by general relativity everywhere.”

Jain’s research is focused on the latter possibility; he is attempting to characterize the properties of this fifth force that disrupts the predictions general relativity makes outside our own galaxy, on cosmic length scales. Jain’s recent breakthrough came about when he and his colleagues realized they could use the troves of data on a special property of a common type of star as an exquisite test of gravity.

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Using Nanocomposites to Improve Dental Filling Performance

After a dentist drills out a decayed tooth, the cavity still contains residual bacteria. Professor Huakun (Hockin) Xu says it is not possible for a dentist to remove all the damaged tissue, so it’s important to neutralize the harmful effects of the bacteria, which is just what the new nanocomposites are able to do.

Rather than just limiting decay with conventional fillings, the new composite he has developed is a revolutionary dental weapon to control harmful bacteria, which co-exist in the natural colony of microorganisms in the mouth.

“Tooth decay means that the mineral content in the tooth has been dissolved by the organic acids secreted by bacteria residing in biofilms or plaques on the tooth surface. These organisms convert carbohydrates to acids that decrease the minerals in the tooth structure,” says Xu, director of the Division of Biomaterials and Tissue Engineering in the School’s Department of Endodontics, Prosthodontics and Operative Dentistry.

The researchers also have built antibacterial agents into primer used first by dentists to prepare a drilled-out cavity and into adhesives that dentists spread into the cavity to make a filling stick tight to the tissue of the tooth. “The reason we want to get the antibacterial agents also into primers and adhesives is that these are the first things that cover the internal surfaces of the tooth cavity and flow into tiny dental tubules inside the tooth,” says Xu.

The main reason for failures in tooth restorations, says Xu, is secondary caries or decay at the restoration margins. Applying the new primer and adhesive will kill the residual bacteria, he says.

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