Sunday, March 8, 2009

Glow, Little E. Coli: Making Luminous Bacteria


A team of Michigan Technological University researchers led by Associate Professor of Chemistry Haiying Liu has discovered how to make a strain of E. coli glow under fluorescent light. The technique could eventually be used to track down all sorts of pathogens and even help in the fight against breast cancer.


E. coli bacteria are naturally found in animal intestines and are usually harmless. But when virulent strains contaminate food, like spinach or peanuts, they can cause serious illness and even death.

The researchers' trick takes advantage of E. coli's affinity for the sugar mannose. Liu's team attached mannose molecules to specially engineered fluorescent polymers and stirred them into a container of water swimming with E. coli. Microscopic hairs on the bacteria, called pili, hooked onto the mannose molecules like Velcro, effectively coating the bacteria with the polymers.

Then the researchers shined white light onto E. coli colonies growing in the solution. The bugs lit up like blue fireflies. "They became very colorful and easy to see under a microscope," said Liu.

The technique could be adapted to identify a wide array of pathogens by mixing and matching from a library of different sugars and polymers that fluoresce different colors under different frequencies of light. If blue means E. coli, fuchsia could one day mean influenza.

With funding from a Small Business Innovation Research grant from the National Institutes of Health, Liu is adapting the technique to combat breast cancer. Instead of mannose, he plans to link the fluorescent polymers to a peptide that homes in on cancer cells.

Once introduced to the vascular system, the polymers would travel through the body and stick to tumor cells. Then, illuminated by a type of infrared light that shines through human tissue, the polymers would glow, providing a beacon to pinpoint the location of the malignant cells.

The technique would allow surgeons to easily identify and remove malignant cells while minimizing damage to healthy tissue.

http://www.sciencedaily.com/releases/2009/03/090305170601.htm

Thursday, March 5, 2009

EARTH HOUR


THIS IS THE WORLD’S FIRST GLOBAL ELECTION, BETWEEN EARTH AND GLOBAL WARMING



On March 28 you can VOTE EARTH by switching off your lights for one hour.Or you can vote global warming by leaving your lights on.

The results of the election are being presented at the Global Climate Change Conference in Copenhagen 2009. We want one billion votes for Earth, to tell world leaders that we have to take action against global warming.
To get involved, all you need to do is: 1. Go to the site - www.voteearth2009.org 2. Register with Friend Connect 3. Send to a friend and get more people to sign up. It would be great if you could help getting more people involved. Thanks for your help.


VOTE EARTH, BECAUSE EVERY VOTE COUNTS


Tuesday, March 3, 2009

FROM STEM CELLS TO NEW ORGANS


A new report brings bioengineered organs a step closer, as scientists from Stanford and New York University Langone Medical Center describe how they were able to use a "scaffolding" material extracted from the groin area of mice on which stem cells from blood, fat, and bone marrow grew. This advance clears two major hurdles to bioengineered replacement organs, namely a matrix on which stem cells can form a three-dimensional organ and transplant rejection.

"The ability to provide stem cells with a scaffold to grow and differentiate into mature cells could revolutionize the field of organ transplantation," said Geoffrey Gurtner, M.D., Associate Professor of Surgery at Stanford University and a senior researcher involved in the work.
To make this advance, Gurtner and colleagues first had to demonstrate that expendable pieces of tissue (called "free flaps") could be sustained in the laboratory. To do this, they harvested a piece of tissue containing blood vessels, fat, and skin from the groin area of rats and used a bioreactor to provide nutrients and oxygen to keep it alive. Then, they seeded the extracted tissue with stem cells before it was implanted back into the animal.

Once the tissue was back in the mice, the stem cells continued to grow on their own and the implant was not rejected. This suggests that if the stem cells had been coaxed into becoming an organ, the organ would have "taken hold" in the animal's body. In addition to engineering the stem cells to form a specific organ around the extracted tissue, they also could be engineered to express specific proteins which allows for even greater potential uses of this technology.

"Myth has its lures, but so does modern science. The notion of using one tissue as the scaffold for another is as old as the Birth of Venus to the Book of Genesis," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "Eve may or may not have been formed from Adam's rib, but these experiments show exactly how stem cell techniques can be used to turn one's own tissue into newly-formed, architecturally-sound organs."