Category Archives: Health Care

Arteriovenous Malformation Explanation

What is arteriovenous malformation (AVM)?

An AVM is a cluster of abnormally formed blood vessels. In medical images, it looks like a tangle of arteries and veins. About 300,000 people in the U.S. have these malformations, but most AVMs never cause any symptoms. The malformations can occur in various places around the body, however, those in the brain or spinal cord can cause the most widespread damage, because they affect the central nervous system.

AVMs disrupt the normal system used to provide oxygen to the brain. Ordinarily, arteries deliver oxygenated blood to the brain and veins return it to the heart and lungs. But in an AVM, blood that should be in an artery can flow through a vein. When that happens, part of the brain may not get enough oxygen. Also, veins are not meant to handle the high pressures and fast blood flow of arteries. So they may expand or even rupture, causing bleeding in the brain.

Diabetes Breakthrough

Diabetes breakthrough by Tom Blackwell:

In a discovery that has stunned even those behind it, scientists at a Toronto hospital say they have proof the body’s nervous system helps trigger diabetes, opening the door to a potential near-cure of the disease
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The researchers caution they have yet to confirm their findings in people, but say they expect results from human studies within a year or so. Any treatment that may emerge to help at least some patients would likely be years away from hitting the market.

More: Canadian scientists reverse diabetes in mice – Type 1 Diabetes May Be Caused By Disruption of Link Between Nerve Cells and Beta Cells

Scientists Building a Safer Mosquito

Scientists building a better mosquito by Catherine Clabby:

Eliminating the pests appears impossible. But scientists are attempting to re-engineer them so they cannot carry disease. If they manage that, they must create enough mutants to mate with wild insects and one day to outnumber them.

Researchers chasing this dream, including an N.C. State University entomologist, know they may court controversy. Genetically modified crop plants such as soybeans, corn and cotton have become common in the United States, but an altered organism on wings would be a first.
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Gould is working on the project with scientists on four continents. They landed $19.7 million under a Grand Challenges in Global Health grant offered by the Gates philanthropy and a National Institutes of Health foundation. The funders selected researchers ready to collaborate rather than compete on risky research aimed at solving massive health threats in poor places.

The genetic tinkering is focused at first on dengue, a tropical virus re-emerging in Asia, Latin America and Africa. While dengue claims a fraction of the million or more victims that malaria kills annually, it strikes 50 to 100 million people each year with severe flu symptoms. Outbreaks disrupt families and communities and overburden health systems.

Ageless Turtles

All but Ageless, Turtles Face Their Biggest Threat: Humans by Natalie Angier:

Dr. Christopher J. Raxworthy, the associate curator of herpetology at the American Museum of Natural History, says the liver, lungs and kidneys of a centenarian turtle are virtually indistinguishable from those of its teenage counterpart, a Ponce de Leonic quality that has inspired investigators to begin examining the turtle genome for novel longevity genes.

“Turtles don’t really die of old age,” Dr. Raxworthy said. In fact, if turtles didn’t get eaten, crushed by an automobile or fall prey to a disease, he said, they might just live indefinitely.

Turtles have the power to almost stop the ticking of their personal clock. “Their heart isn’t necessarily stimulated by nerves, and it doesn’t need to beat constantly,” said Dr. George Zug, curator of herpetology at the Smithsonian Institution. “They can turn it on and off essentially at will.”

How Does the Immune System Remember

Scientists find key to immune system’s ability to remember

The protein, which scientists call Lck, is essential for immune system T cells – white blood cells that attack virus-infected cells, foreign cells and cancer cells… Lck is important in helping “naive” T cells – those cells that have never been exposed to a particular pathogen – capture the receptor template of the invading agent and store it for future reference… Following infection or vaccination, Lck initiates a biochemical chain of events that vastly increases the number of T cells that march off to combat the invader.

After the infection subsides, the number of T cells marshaled to fight that agent decreases dramatically. But a smaller subset, known as “memory” cells, retains the imprint of its previous encounter should the pathogen make a return appearance. According to the study, while Lck primes naive cells to fight a pathogen, it is not required by memory cells, which initiate the fast and furious response when that same pathogen comes calling again years later. Unlike naive T cells, which are confined to the lymphatic system, memory T cells are found everywhere in the body, enabling them to sense and react more quickly when an infectious agent is reencountered.

Flushed Drugs Pollute Water

Flushed drugs pollute water by Ron Seely (site broke the link so I removed it):

An extensive nationwide study by the U.S. Geologic Survey has found evidence of pharmaceuticals including antibiotics and hormonal drugs, such as birth control pills, in surface waters throughout the nation.
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Whether the presence of drugs in water translates into human health impacts is still being studied. But research has shown that drugs containing hormones such as estrogen are causing changes and deformities in fish and other aquatic creatures.

The World Health Organization indicates that human risk assessments have shown low concentrations of pharmaceuticals in drinking water have a negligible health risk. But WHO points out that long-term exposures have not been evaluated, especially in populations with other illnesses or with compromised immune systems. Also, according to the WHO, antibiotics in water supplies are a potential concern because the most frequently used antibiotics are becoming less effective as the infections they are designed to combat become resistant.

Human Sonar – Echolocation

The Mystery of Sonar Boy:

Ben Underwood’s echolocation isn’t a hoax, but it’s not an unexplained mystery, either. Ben really can sense nearby objects with reflected sound waves. But so can you.
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Go ahead and try out the skill you never knew you had. First, close your eyes and put on a blindfold, and then ask a friend to move a frying pan forward and backward in front of your face. Now start making noises—any noises you want. You can click your tongue like Sonar Boy, or you can whistle, or you can sing a scale. With a little bit of practice, you’ll be able to tell when the pan is close to you and when it’s not.

Also see, two interesting videos, CBS story and an Ellen show appearance. And read a 2003 BBC article on how the Blind ‘see with sound’.

Anti-microbial ‘paint’

anti-microbial ‘paint’ kills flu, bacteria

A new “antimicrobial paint” developed at MIT can kill influenza viruses that land on surfaces coated with it, potentially offering a new weapon in the battle against a disease that kills nearly 40,000 Americans per year. If applied to doorknobs or other surfaces where germs tend to accumulate, the new substance could help fight the spread of the flu, says Jianzhu Chen, MIT professor of biology.
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The “antimicrobial paint,” which can be sprayed or brushed onto surfaces, consists of spiky polymers that poke holes in the membranes that surround influenza viruses. Influenza viruses exposed to the polymer coating were essentially wiped out. The researchers observed a more than 10,000-fold drop in the number of viruses on surfaces coated with the substance.
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One of the benefits of the new polymer coating is that it is highly unlikely that bacteria will develop resistance to it, Klibanov said. Bacteria can become resistant to traditional antibiotics by adjusting the biochemical pathways targeted by antibiotics, but it would be difficult for bacteria to evolve a way to stop the polymer spikes from tearing holes in their membranes.

More Nutritious Wheat

A wheat gene, now present but inactive, could boost nutrition if it were active. Wheat’s lost gene helps nutrition

The gene occurs naturally in wheat, but has largely been silenced during the evolution of domestic varieties. Researchers found evidence that turning it back on could raise levels of the nutrients in wheat grains.

Writing in the journal Science, they suggest that new varieties with a fully functioning gene can be created through cross-breeding with wild wheat. “Wheat is one of the world’s major crops, providing approximately one-fifth of all calories consumed by humans,”
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“This experiment confirmed that this single gene was responsible for all these changes.”

The researchers deduced that the reverse process – enhancing GPC-B1 activity – ought to produce plants which have higher levels of these nutrients in their grains and mature faster. The UC Davis team is already making such varieties, not by genetic engineering but through crossing domesticated wheat plants with wild relatives.

H5N1 Influenza Evolution and Spread

H5N1 Influenza – Continuing Evolution and Spread from the New England Journal of Medicine:

The current H5N1 virus is apparently not well “fitted” to replication in humans, although the genetic makeup of a small proportion of humans supports attachment and replication of the virus, if not its transmission. The specific receptor for the current avian influenza virus ({alpha}2-3 sialic acid) is found deep in the respiratory tract of humans
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Clearly, we must prepare for the possibility of an influenza pandemic. If H5N1 influenza achieves pandemic status in humans – and we have no way to know whether it will – the results could be catastrophic.