Archive for April, 2009

“Pandemic” Depends on Single Case

April 30, 2009

The H1N1 influenza epidemic is poised to become a pandemic. If Spanish Health Ministry officials and the World Health Organization confirm ‘community spread’ of one of ten cases in Spain, it’s a ‘Phase 6’ pandemic.
This may seem a bit arbitrary, but WHO has a protocol that triggers various actions and it has to set the bar somewhere.
Of ten probable H1N1 cases in Cataluna, nine had traveled to Mexico in recent days. It’s that tenth case that could be ‘community spread,’ that is, acquired in Spain. That would be a second country, Spain (after Mexico) in a second WHO region, Europe (after North America) where this novel virus is efficiently transmitted between people.

Your New PET (Photonically-Enhanced Tetrapod)

April 27, 2009

Fluorescent Fido
Take a beagle, add some genes from a sea anenome, and voila- a glow in the dark dog.
It wasn’t exactly that easy for Byeong-Chun Lee and colleagues of Seoul National University in South Korea, but their work sure made headlines.
This first-ever transgenic dog was a proof-of-concept canine that shows how “easy” it is to inject alien genetic material into an animal.
How They Did It
Researchers reportedly started with beagle fibroblasts, the most common cells of mammalian connective tissue. They inserted a retrovirus which carried a gene from sea anemones that in turn expresses a protein which glows red when struck by ultraviolet light. They put the hybrid fibroblast nucleus into a beagle egg and through in vitro fertilization implanted it in a surrogate mother beagle.
This doesn’t work very well. They tried it with more than 340 embryos and 20 different mothers. Only seven developed into fetuses, one of those died and another puppy died 11-weeks after birth. Five red-glowing beagles survived, however, and they reportedly will be bred to pass on their fiery-skinned character.
Why They Did It
Besides the ‘gee-whiz’ factor, dogs have been studied for years because of some interesting similarities to humans. For instance, dogs can get narcolepsy, a mysterious, apparently genetically related sleep disorder than can sometimes cause sudden, uncontrollable sleepiness or even a startling loss of muscle function known as cataplexy. The weird thing about narcoleptics is that even though they seem unusually sleepy, many are in fact sleep-deprived and have disabling disruptions in their lives. There is some evidence that as least some narcolepsy may be an autoimmune disorder. So understanding dog genes may be an avenue to help the 1 in 2000 people with narcolepsy.
Stanford geneticist Greg Barsh, who studies dog and mice skin and hair coloration as a way to understand stem cell renewal, says the transgenic dog is an important step.
Why They May Not Do It Again
Some scientists point out Lee’s process could not control where the new gene was inserted. The beagle egg/retrovirus process would not allow researchers to create so-called ‘knock-out’ animals, such as has been done with mice. (The mouse technique uses embryonic stem cells, and has resulted in more than ten thousand different varieties of ‘knock-out’ mice with selected genes disabled, providing researchers with amazing insights into genetic disorders.) The flashy beagles may end up being just another quirky side-step in scientists’ quest to understand genetics.
Many people think absent some significant value to human-kind, this kind of research amounts to cruelty.
You be the judge.

Lab on a chip saves lives, snags crooks

April 25, 2009

I watched four day old Andres Heredia sleep in a warmed incubator on the third floor Neonatal Intensive Care Unit of Children’s Hospital Oakland.  His little fingers grasp the air as his eyes move about under lids.  He weighs only about four pounds, has a blue ventilator tube down his tiny throat that helps his premature lungs take in oxygen.

 Not too long ago, babies such as Andres were at high risk for significant life-threatening swings in blood chemistry.  Their premature bodies are just not fully ready for life outside the womb.  But today, remarkable technology sits at his bedside, monitoring blood gases, electrolytes and even sugar levels with a precision and speed undreamed of just a year ago.

It’s a lab-on-a-chip, developed in coordination between the hospital and Canadian device maker Epocal, that can spot trends and spikes in his body chemistry within 30 seconds of a painless blood draw from a catheter.

“This allows me to adjust the critical parameters immediately, giving him the best possible chance,” says Dr. David Durand, Chief of Neonatology.  “He’s moderately sick, but going in the right direction, thanks in part to this technology.”

The device looks like a PalmPilot, with a disposable credit-card shaped micro-fluid sensor that slides in like an ATM card for each reading.  It has a screen that flashed red with an exclamation mark when CO2 levels were out of parameter.  The test results are wirelessly sent direct to Andres’ digital medical record, and are accessible by physicians and nurses staff from their computers.

“This keeps him comfortable and safe,” says Respiratory Specialist Dolio Horton-Butler, who helped improve the device for use in a tertiary care setting.  “Test results used to take 30 minutes or longer, and sometimes were delayed in transit; we wouldn’t know what was wrong or how to adjust the respirator until the lab techs sent us the report.”  She held the new device in her left hand, tapped a few keys with a stylus, then reached down and confirmed settings, less than a minute after arriving at Andres’ bedside.

A few miles away at UC Berkeley’s Lewis Hall, College of Chemistry Dean Richard Mathies opend the door to his lab, to show me the latest advance on lab-on-a-chip: a lunchbox sized DNA analyzer that Mathies says can do in minutes, what conventional laboratories take weeks to accomplish.

Mathies is among the world’s foremost experts and a pioneer in the field of microfluidics.  He says the technology can quickly identify patients who are at risk of adverse drug reactions, or spot people whose genetics put them at risk of diseases such as diabetes or Alzheimer’s.  It can also catch criminals.

“We can do realtime genetic analysis of a very small sample of DNA material, at the scene of a crime, and have a suspect database match within 2 hours of arrival,” says Prof. Mathies.  

He held up a CD-sized four-layer glass ‘lab’ and pointed to a crazily-tiny pattern of etchings of tubes and channels that do the wet chemistry of an entire room full of equipment.  “We plan to send this to Mars in seven years, to look for the telltale ‘left-handed’ amino-acids that signify life.”

Meanwhile, neonatal intensive care nurses prepared little Andres for breathing on his own.  Doctors expect to remove his breathing tube within a few hours: an awesomely huge sign of life for the youngster whose second-grade class could be wowed by the news of life on Mars.

To the Moon, Alice! For Ice!

April 11, 2009

“Bang, zoom! To the Moon, Alice!”- Jackie Gleason as Ralph Cramden, The Honeymooners.

Water on the Moon? If humans are ever to live there, water is important for life, for making things and even for future rocket fuel (think hydrogen and oxygen.) Water is insanely expensive to truck up there, so what if we can harvest any water off the lunar surface?

I spoke with NASA Ames scientist Daniel Andrews the mission manager for a team hoping to crash a spent rocket booster into a lunar crater this Fall. Launching around June 2 or a little later, the LCROSS spacecraft and its booster will orbit the earth out around 250,000 miles, on a polar orbit that coincides with the north or south poles of the Moon.

About a month before impact, the team will decide on a specific crater and point the booster and it’s now separated spacecraft at a spot they hope may harbor water ice. Think a shadowy niche at the foot of a crater wall. Since the lunar poles get almost no sunlight, there could be ancient primordial ice hiding there under the regolith.

The impact (think of a school bus going 5600 mph) should punch a crater six feet deep and 60 feet across, throwing a plume of dust and stuff to about 6 miles above the Moon. Telescopes (including the Hubble Space Telescope) as well as the LCROSS itself will scan the debris for signals of water vapor.

Impact could occur around mid-October. It turns out to be very tricky, balancing sun angle, earth-viewing angle, lunar wobble and the needs of a companion spacecraft, the Lunar Reconnaisance Orbiter. Andrews says he’s glad he has a rocket scientist on his staff.

The mission came together in about two years with a total cost of about $79 million, a shoestring budget for a major science spacecraft. Andrews says his team saved money by using off-the-shelf commercial components wherever possible, fixing them to a central aluminum cylinder that was already designed for holding a satellite during launch.  It’s not ‘faster, better, cheaper’ he says, “it’s faster, good enough, and cheaper.”

Worried about the crash hurting the Moon? Andrews says a similar energy impact (by meteor) occurs every few days. NASA also designed the rocket booster to have minimal contaminants (it does contain some water and other hydrogen compounds that could confound the search for lunar water) and most of the stuff will vaporize on impact.

If you have a good amateur astronomer quality telescope, you might catch a glimpse of the impact and debris cloud.  Stay tuned.