Category Archives: Life Science

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.

Deer Rescued 1.5 miles Offshore

Bambi Caught 1.5 miles OFFSHORE

They saw what appeared to be a seal with its snout out of the water, but they didn’t think any seals were around their fishing grounds and they kept watching. Soon they realized it was a deer trying desperately to keep afloat – and obviously losing the battle. Fearing the whitetail would get snagged in their lines they cranked in their rigs. Then the deer headed straight for the boat possibly thinking it was a spit of land.

But as it got closer and saw the two fishermen aboard, it had second thoughts. With its nose barely out of the water, it appeared to have been swimming all night, said Campbell. “Since the fish weren’t biting, we thought we’d give it a hand. Bo grew up around cows, was really handy with a bow line and lasooed the deer on the first attempt.”
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to the closest beach, Kent Point, where I beached the boat and we carefully unloaded our catch on the sand. We untied him and jumped back.

“Too weak to stand, he just sat there quivering. We picked him up again and put his feet underneath him, but he still couldn’t walk or stand. We left him sitting there looking at us. Before we left, I looked him in the eye and said ‘See you on opening day; payback time.’

See link for photos. Related:The Cat and a Black Bear – Polar Bear Playing with Wolves – Water Buffaloes, Lions and Crocodiles Oh My – The Engineer That Made Your Cat a Photographer

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.

Real-Time Evolution

Real-Time Evolution, Researchers find evidence that a variety of African electric fish may be approaching speciation:

Researchers from Cornell University found that genetically identical fish are sending out two different electric signals, and certain male members of the species ignore some signals emitted by females, responding only to pulses similar to their own. The strict selectivity for specific signals observed in these electric fish may eventually result in different mating groups, leading researchers to surmise that the fish could be on the verge of speciation.

“Evolution is a historical, inferential science—you can’t really see it happening before your eyes,” said Matt Arnegard, a neurobiology and behavior postdoc at Cornell and lead author of the study, which appears in the June issue of The Journal of Experimental Biology. “We think maybe this is an example where we’re really close to seeing it happen before our eyes.”

Monarch Butterfly Migration

Monarch Butterfly

Helping track the monarch butterfly migration is a very cool interactive learning projects for students. The Monarch Butterfly Journey North site includes a great wealth of resource with real time reports and answers to science questions.:

A massive migration across Oklahoma, Arkansas, and Kansas this week resulted in the most spectacular sightings of the season. Most miraculous was the mile of clustering monarchs discovered on Sunday in a sunflower field in Kansas. Just think…It’s the first week of October and migrating monarchs are still being spotted across the north.

From the Monarchs in the Classroom website:

Unlike most other insects in temperate climates, monarch butterflies cannot survive a long cold winter. Every fall, North American monarchs fly south to spend the winter at roosting sites. Monarchs are the only butterflies to make such a long, two-way migration, flying up to 3000 miles in the fall to reach their winter destination. Amazingly, they fly in masses to the same winter roosts, often to the exact same trees. Their migration is more the type we expect from birds or whales than insects. However, unlike birds and whales, individuals only make the round-trip once. It is their children’s grandchildren that return south the following fall.

Monarch Travels (2006 post)

To test their ability to reorient themselves, Dr. Taylor has moved butterflies from Kansas to Washington, D.C. If he releases them right away, he said, they take off due south, as they would have where they were. But if he keeps them for a few days in mesh cages so they can see the sun rise and set, “they reset their compass heading,” he said. “The question is: How?”

New Hearing Mechanism

MIT finds new hearing mechanism

MIT researchers have discovered a hearing mechanism that fundamentally changes the current understanding of inner ear function. This new mechanism could help explain the ear’s remarkable ability to sense and discriminate sounds. Its discovery could eventually lead to improved systems for restoring hearing.
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t has been known for over half a century that inside the cochlea sound waves are translated into up-and-down waves that travel along a structure called the basilar membrane. But the team has now found that a different kind of wave, a traveling wave that moves from side to side, can also carry sound energy. This wave moves along the tectorial membrane, which is situated directly above the sensory hair cells that transmit sounds to the brain. This second wave mechanism is poised to play a crucial role in delivering sound signals to these hair cells.

Related: Solar Powered Hearing Aid

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.

Mammoth DNA Extracted from Hair

Mammoth DNA extracted from hair reveals ancient secrets

The woolly mammoth hair had been so well preserved that it provided the most accurate DNA sequencing of the extinct animals yet achieved. One of the animals used in the study dated back 50,000 years and its hairs allowed scientists to obtain the oldest complete sequence of mitochondrial DNA.

Three mammoths had been subjected previously to DNA sequencing, two with bone fragments and the third with a sample of muscle tissue.

Results from hair assessed using the sequencing-by-synthesis (SBS) technique were more detailed than bone and muscle samples. Importantly, said researchers, the SBS extraction technique required smaller quantities of ancient material and caused less damage to the preserved specimens.

Mammoths roamed the landscape for about six million years and their disappearance about 10,000 years ago – with a handful of dwarf mammoths surviving on remote Siberian islands until little more than 2,000 years ago – has remained a mystery.