Category Archives: Health Care

MRSA Blows Up Defender Cells

Superbug succeeds by blowing up defender cells, scientists learn

While only 14 percent of serious MRSA infections are the community associated kind, they have drawn attention in recent months with a spate of reports in schools, including the death of a 17-year-old Virginia high school student. Both hospital-associated and community-associated MRSA contained genes for the peptides. But their production was much higher in the CA-MRSA, the researchers said.
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The compounds first cause inflammation, drawing the immune cells to the site of the infection, and then destroy those cells. The research was conducted in mice and with human blood in laboratory tests. Within five minutes of exposure to the peptides from CA-MRSA, human neutrophils showed flattening and signs of damage to their membrane, researchers said. After 60 minutes, many cells had disintegrated completely.

“This elegant work helps reveal the complex strategy that S. aureus has developed to evade our normal immune defenses,” Dr. Anthony S. Fauci, NIAID director, said in a statement. “Understanding what makes the infections caused by these new strains so severe and developing new drugs to treat them are urgent public health priorities.”

New and Old Ways to Make Flu Vaccines

New and Old Ways to Make Flu Vaccines by Nell Greenfieldboyce, NPR:

Standard Practice
Pros: Millions of Americans receive this [standard] vaccine every year. It’s safe and well tolerated. Its production begins in hens’ eggs — a tried and true technology for 50 years.
Cons: Eggs must be ordered many months in advance, and millions of doses require millions of eggs.

Live-Attenuated Vaccine
Pros: This newer method of production results in a vaccine that has a flu virus that is crippled, so it can’t cause disease. But the virus is not killed, as is the case in the standard vaccine. The vaccine also can be given as a nasal spray.
Cons: More expensive than standard vaccine, and also produced in eggs. Not approved for young children or older people.

Cell-Based Vaccine
Pros: This vaccine can be produced in giant vats of living cells. Such a production method means it can be scaled up much faster than egg-based vaccines, making it more useful in a pandemic. Several versions have been tested successfully in people.
Cons: Won’t be widely available for a few years. Clinical trials are under way, but no flu vaccine made this way is currently approved by the Food and Drug Administration.

Plumpynut – Food Savior

A Life Saver Called “Plumpynut”

Every year, malnutrition kills five million children — that’s one child every six seconds. But now, the Nobel Prize-winning relief group “Doctors Without Borders” says it finally has something that can save millions of these children. It’s cheap, easy to make and even easier to use. What is this miraculous cure? As CNN’s Anderson Cooper reports, it’s a ready-to-eat, vitamin-enriched concoction called “Plumpynut,” an unusual name for a food that may just be the most important advance ever to cure and prevent malnutrition.

“It’s a revolution in nutritional affairs,” says Dr. Milton Tectonidis, the chief nutritionist for Doctors Without Borders. “Now we have something. It is like an essential medicine. In three weeks, we can cure a kid that is looked like they’re half dead. We can cure them just like an antibiotic. It’s just, boom! It’s a spectacular response,” Dr. Tectonidis says.
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Plumpynut is a remarkably simple concoction: it is basically made of peanut butter, powdered milk, powdered sugar, and enriched with vitamins and minerals. It tastes like a peanut butter paste. It is very sweet, and because of that kids cannot get enough of it. The formula was developed by a nutritionist. It doesn’t need refrigeration, water, or cooking; mothers simply squeeze out the paste. Many children can even feed themselves. Each serving is the equivalent of a glass of milk and a multivitamin.

Killing Germs May Be Hazardous to Your Health

Caution: Killing Germs May Be Hazardous to Your Health

Relman is a leader in rethinking our relationship to bacteria, which for most of the last century was dominated by the paradigm of Total Warfare. “It’s awful the way we treat our microbes,” he says, not intending a joke; “people still think the only good microbe is a dead one.” We try to kill them off with antibiotics and hand sanitizers. But bacteria never surrender; if there were one salmonella left in the world, doubling every 30 minutes, it would take less than a week to give everyone alive diarrhea. In the early years of antibiotics, doctors dreamed of eliminating infectious disease. Instead, a new paper in The Journal of the American Medical Association reports on the prevalence of Methicillinresistant Staphylococcus aureus (MRSA), which was responsible for almost 19,000 deaths in the United States in 2005—about twice as many as previously thought, and more than AIDS. Elizabeth Bancroft, a leading epidemiologist, called this finding “astounding.”

As antibiotics lose their effectiveness, researchers are returning to an idea that dates back to Pasteur, that the body’s natural microbial flora aren’t just an incidental fact of our biology, but crucial components of our health, intimate companions on an evolutionary journey that began millions of years ago.

Nanoengineers Use Tiny Diamonds for Drug Delivery

Nanoengineers Mine Tiny Diamonds for Drug Delivery

Northwestern University researchers have shown that nanodiamonds — much like the carbon structure as that of a sparkling 14 karat diamond but on a much smaller scale — are very effective at delivering chemotherapy drugs to cells without the negative effects associated with current drug delivery agents.
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To make the material effective, Ho and his colleagues manipulated single nanodiamonds, each only two nanometers in diameter, to form aggregated clusters of nanodiamonds, ranging from 50 to 100 nanometers in diameter. The drug, loaded onto the surface of the individual diamonds, is not active when the nanodiamonds are aggregated; it only becomes active when the cluster reaches its target, breaks apart and slowly releases the drug. (With a diameter of two to eight nanometers, hundreds of thousands of diamonds could fit onto the head of a pin.)

“The nanodiamond cluster provides a powerful release in a localized place — an effective but less toxic delivery method,” said co-author Eric Pierstorff, a molecular biologist and post-doctoral fellow in Ho’s research group. Because of the large amount of available surface area, the clusters can carry a large amount of drug, nearly five times the amount of drug carried by conventional materials.

Untidy Beds May Keep us Healthy

Untidy beds may keep us healthy – I knew I was right not to make my bed, I just didn’t know why 🙂

Research suggests that while an unmade bed may look scruffy it is also unappealing to house dust mites thought to cause asthma and other allergies. A Kingston University study discovered the bugs cannot survive in the warm, dry conditions found in an unmade bed. The average bed could be home to up to 1.5 million house dust mites.

The bugs, which are less than a millimetre long, feed on scales of human skin and produce allergens which are easily inhaled during sleep.

Good news. Some other scientist is not being helpful however 🙁

“However, most homes in the UK are sufficiently humid for the mites to do well and I find it hard to believe that simply not making your bed would have any impact on the overall humidity.”

New Approach Builds Better Proteins Inside a Computer

With the aid of more than 150,000 home computer users throughout the world, Howard Hughes Medical Institute (HHMI) researchers have, for the first time, accurately predicted the three-dimensional structure of a small, naturally occurring globular protein using only its amino acid sequence. The accomplishment was achieved with a newly refined computational method for predicting protein structure, which the researchers say can also improve the detail and accuracy of protein structures generated with experimental techniques.

A detailed understanding of a protein’s structure can offer scientists a wealth of information – revealing intricacies about the protein’s biological function and suggesting new ideas for drug design. Researchers often rely on x-ray crystallography to determine a protein’s structure – bombarding the molecule with x-rays and analyzing the resulting diffraction pattern to piece together its structure. But not all proteins are amenable to this time-consuming technique, and those that are do not always yield the atomic-level data researchers would like to have.
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The complex algorithms the researchers developed to carry out these analyses demand a tremendous amount of computing power. More than 150,000 home computer users around the world were an integral part of the project, volunteering their computers to participate in the quest for protein structures through Rosetta@home, a distributed computing project that is based on the Berkeley Open Infrastructure for Network Computing (BOINC) platform.

You can join in via Rosetta@home. Related: Protein Knots – molecular sieve advances protein research – Protein Science Art – Nobel Laureate Discusses Protein Power

Live Long and Prosper

Live Long and Prosper: A Conversation with Cynthia Kenyon:

Cynthia Kenyon, PhD, director of the UCSF’s Larry L. Hillblom Center for the Biology of Aging, smiles a lot these days. And with good reason. She has aging cornered and she knows it. In less than 20 years, her once-crazy idea – that genes regulate aging – has not only gone mainstream, but spawned a huge field of research with giant conclaves and dozens of journal articles published every year.
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One of Kenyon’s lab rotation students – Ramon Tabtiang – in one of his very first experiments, picked a needle out of the haystack that is the C. elegans genome. In short, he found a mutant gene, dubbed daf-2, that made worms live twice as long. C. elegans was — and is — a favorite model for developmental biologists and geneticists because its simple structure and entire three-week life are easily scrutinized under the microscope.

Watching the mutant worms, says Kenyon, was like “witnessing a miracle.” Not only did these worms live longer, they retained good muscle tone, squirmed, sought food and stayed youthful. In comparison, normal, or wild, worms of the same two-week age were flabby, tattered and sedentary. They looked old. The message was clear. The rate of aging was not “fixed in stone,” after all. It could be slowed.

In the years since, Kenyon and her team have made more eye-popping discoveries, including the role of a companion gene, called daf-16, that controls on or off signals in still other genes. Learning more about the insulin pathway in which these genes operate helped her to understand a cascade of signals and responses as they reverberate through individual tissues.

Better yet, by using this information to tweak here and there in the worm genome, Kenyon and her laboratory colleagues have been able to extend a worm’s life up to six times the normal span, with no significant decline in vitality until late in life.

2007 Nobel Prize in Physiology or Medicine

Nobel Prize in Physiology or Medicine 2007 awarded to Mario R. Capecchi, Martin J. Evans and Oliver Smithies for their discoveries of “principles for introducing specific gene modifications in mice by the use of embryonic stem cells”

This year’s Nobel Laureates have made a series of ground-breaking discoveries concerning embryonic stem cells and DNA recombination in mammals. Their discoveries led to the creation of an immensely powerful technology referred to as gene targeting in mice. It is now being applied to virtually all areas of biomedicine – from basic research to the development of new therapies.

Gene targeting is often used to inactivate single genes. Such gene “knockout” experiments have elucidated the roles of numerous genes in embryonic development, adult physiology, aging and disease. To date, more than ten thousand mouse genes (approximately half of the genes in the mammalian genome) have been knocked out. Ongoing international efforts will make “knockout mice” for all genes available within the near future.

Mario R. Capecchi, born 1937 in Italy, US citizen, PhD in Biophysics 1967, Harvard University, Cambridge, MA, USA. Howard Hughes Medical Institute Investigator and Distinguished Professor of Human Genetics and Biology at the University of Utah, Salt Lake City, UT, USA.

Sir Martin J. Evans, born 1941 in Great Britain, British citizen, PhD in Anatomy and Embryology 1969, University College, London, UK. Director of the School of Biosciences and Professor of Mammalian Genetics, Cardiff University, UK.

Oliver Smithies, born 1925 in Great Britain, US citizen, PhD in Biochemistry 1951, Oxford University, UK. Excellence Professor of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, NC, USA.

The USA gains 2 Nobel Laureates born elsewhere – the incidence of this happening 30 years from now will be less I believe than it has been recently.

Finding Protease Inhibitors

Can’t Cut This by Kathleen M. Wong, ScienceMatters@Berkeley:

When a malaria parasite lands in your blood, one of the first things it does is whip out its scissors. As fast as it can, this protozoan snips the hemoglobin in red blood cells to get the nutrients it needs to survive. Of course, the microbe behind this deadly disease doesn’t actually deploy stainless-steel blades. Instead, it uses an array of biochemical scissors known as proteases.

Proteases are enzymes that snip proteins. They recognize certain strings of amino acids on a substrate protein, bind to this area, then break a nearby chemical bond. Proteases can destroy proteins by snipping them in half, as in malaria. They can also activate proteins by lopping off atoms covering a reactive site.

This versatility has made proteases critical to all manner of organisms, from viruses to plants to humans. Over the past 10 years, protease inhibitor drugs have become indispensable in the fight against AIDS, cardiovascular disease and diabetes. But finding protease inhibitors is no picnic. Humans manufacture tens of thousands of proteins; figuring out which of these a protease targets is extremely challenging and time consuming.
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Instead of mixing liquid chemicals and painstakingly purifying them again at each step, he attaches his precursor molecules to polystyrene beads resembling sand grains.