Doctors already use concentrated sound waves to see through solid tissue and take a look inside the body, as with ultrasound scans. But in this week’s Proceedings of the National Academy of Sciences, Caltech scientists say they’ve developed a metamaterial that focuses sound to such a high concentration that it could go on the offensive, targeting cancers or kidney stones while leaving the surrounding tissues alone. Oh, and one other thing: The military could use it to make weapons.

“The beauty of this system is that it’s just a bunch of ball bearings that we control with weights,” said Chiara Daraio [Discovery News], a member of the research team. Caltech’s acoustic lens relies on the same principle as Newton’s cradle—that toy your high school science teacher probably kept on his or her desk with metal balls on strings that demonstrated the conservation of energy. In this design, 21 parallel chains each contain 21 bearings. When the team strikes one end, it starts a compression wave that carries through the system. But instead of having the last ball swing out like a pendulum and bring the momentum back into the system, like the toy does, the acoustic lens focuses all the energy at the end of the system onto one spot, just a few inches away from the metamaterial.

(more…)

Canada has approved for limited production a genetically engineered, environmentally friendly pig.

The “Enviropig” has been genetically modified in such a manner that its urine and feces contain almost 65 percent less phosphorus than usual. That could be good news for lakes, rivers, and ocean deltas, where phosphorous from animal waste can play a role in causing algal blooms. These outbursts of algae rapidly deplete the water’s oxygen, creating vast dead zones for fish and other aquatic life [National Geographic].

All living creatures need phosphorus, as the element plays an important role in many cellular and organ functions. Domesticated pigs get their daily dose from corn or cereal grains, but not without a struggle. These foods contain a type of phosphorus that is indigestible to the pigs, so farmers also feed their pigs an enzyme called phytase to allow the animals to break down and digest the phosphorus. But ingested phytase isn’t as effective at breaking down phosphorus as phytase created inside the pig would be, so a fair amount of the element gets flushed out in pig waste. That waste, in turn, can make its way into the water supply [National Geographic].

(more…)

In a far-reaching judgment that could have major implications for the biotech industry, a federal judge in Manhattan has struck down patents related to two human genes linked to hereditary breast and ovarian cancers, BRCA1 and BRCA2.

Myriad Genetics held the patents, and women who want to find out if they have a high genetic risk for these cancers have to get a test sold by Myriad, which costs more than $3,000. Plaintiffs in the case had said Myriad’s monopoly on the test, conferred by the gene patents, kept prices high and prevented women from getting a confirmatory test from another laboratory [The New York Times]. In his decision, United States District Court Judge Robert W. Sweet found that the company’s patents were invalid because the genes are “found in nature,” and products of nature can’t be patented. In essence, he agreed with the plaintiffs’ argument that the genetic code contained in each human being’s cells shouldn’t be private property.

Tuesday’s decision, if upheld, could have wide repercussions for the multi-billion dollar biotech industry, which is built on more than 40,000 gene patents. Already, about 20 percent of the human genes have been patented. The decision, however, is not binding on other federal courts and other judges may or may not abide by it. But it does the set the stage for years of litigation over other gene patents. Myriad Genetics plans to appeal the judgment.

(more…)

When a person has a heart attack, the heart repairs its damaged muscle by forming scar tissue. As a result, the heart never truly goes back to the way it was. But when a zebrafish has a heart injury, like having a large chunk of it chopped off, it grows a brand new piece to replace it.

Two independent reports published in the journal Nature show that within days of an injury to its heart, the zebrafish has the remarkable ability to regenerate most of the missing cardiac tissue using mature heart cells–not stem cells, as some researchers had suspected.

The findings help explain why human beings can’t regenerate a heart or missing limbs. The reports contradict a previous study (pdf) done by one of the research teams in 2006 that suggested that stem cells, the general all-purpose cells that develop into all the mature and functional cells of the body, were responsible for self-repair.

The finding suggest that doctors have been on the wrong track with recent stem cell-based therapies for heart attack patients. Many heart patients have received injections of stem cells, often ones taken from their own bone marrow. But the beneficial effects have generally been unremarkable [The New York Times].

(more…)

We’re only a week away from the 2010 Winter Olympics opening in Vancouver, and the return of the games brings with it the return of crazy stories about how far world-class athletes will go to get even the tiniest edge, legal or illegal. In the journal Science this week, researchers led by geneticist Theodore Friedmann take the opportunity to warn about gene doping, the next looming crisis in cheating at high-stakes athletics.

Genetic doping isn’t new to the headlines—the International Olympic Committee banned it in 2003. But its prevalence is growing, especially since improving testing is starting to weed out more standard forms of cheating like steroids and EPO, a hormone that boosts red blood cell production. Three years ago, German track coach Thomas Springstein was busted after unsuccessfully trying to score Repoxygen, an experimental gene therapy drug that boosts red blood cell production, for his runners. At the Olympics in Beijing, an unidentified Chinese doctor offered stem cell injections to a German journalist posing as a swim coach [Wired.com].

(more…)

Now that many U.S. farmers have grown used to genetically modified (GM) soy and corn, the controversy surrounding GM crops may shift over to GM eucalyptus–a fast-growing Australian tree that, in its unmodified strains, dominates the tropical timber industry.

Two industry giants, International Paper Co. and MeadWestvaco Corp. have formed a biotech venture called ArborGen LLC that is looking to introduce this tree to the southeastern forests of the United States. The company is seeking greater governmental deregulation so it can roll out its plans of replacing native pines in southeastern plantation forests with the genetically engineered eucalyptus, which can survive freezing winter temperatures.

Unlike the pine trees used in Southern plantations — which have quietly helped displace tobacco in the region’s economy — eucalyptus can deploy a full canopy of leaves within a few years. It is greedy for carbon, and within 27 months can grow to 55 feet in height [The New York Times].  ArborGen points out that the high growth rate will allow the company to grow more wood on less land, which could provide a boost to the region’s timber exports. What’s more, the wood could potentially serve as a biofuel feedstock.

(more…)

Cells just keep surprising us. Researchers have now found that, with a little genetic tweaking, they can transform skin cells into brain cells without having to first reprogram them to act like multipurpose stem cells. This finding, the first of its kind, is in this week’s edition of the journal Nature.

The researchers did their study on mice. They induced the change by inserting only three genes into cultured skin cells. Once those three genes activated, the skin cells converted into fully functioning nerve cells that even formed synapse connections with the other converted nerve cells [Popular Science]. That change took less than a week, a surprisingly rapid rate. Said team member Marius Wernig: “These are fully functional neurons. They can do all the principal things that neurons in the brain do” [AFP].

(more…)

One small step for flashing bacteria, one giant leap for synthetic biology. In a new Nature study, molecular biologist Jeff Hasty and his team say they have created a line of E. coli bacteria that flash in fluorescent light and keep time like a clock.

Previously, scientists had engineered only single cells to become oscillators — devices that could count time by performing a particular activity on a cyclical schedule [Nature News]. Back in 2008, Hasty and his team created an oscillator for single cells that could be set to temperature or chemical triggers. But now the researchers have induced a whole host of bacteria to work together to keep time by taking advantage of the way they collaborate naturally: quorom sensing.

(more…)

We’ve brought you stories of lab-created blood cells able to simulate red blood cells in humans, or to act like platelets in rodents and stop bleeding. Now, in a study soon to be published in the Proceedings of the National Academy of Sciences, comes a new, even smaller creation for our bloodstreams: A nanoparticle that could target and latch onto only the damaged cells in arteries around the heart to deliver drugs there.

The MIT researchers, led by Robert Langer, have developed other nanoparticles to target cancer; this new particle they call a “nanoburr,” named for those seeds covered in bristles or hooks that latch onto animals passing by. Its nanoburrs are coated with proteins which can only stick to a structure in the blood vessel wall called the “basement membrane.” This is only exposed when the wall is damaged, so only damaged sections of blood vessel are targeted [BBC News]. Then the particle can slowly release the drug stored inside.

(more…)

UPDATE: On Tuesday, Gilles-Eric Séralini responded by email to the criticisms in this post. Mostly, he says, the answers can be found in the study itself. But where he has addressed these criticisms in particular, we have included that below in italics. Séralini stresses that while the data he had available was limited, his findings show that you can’t say these GM corn varieties are safe enough to put on the market and authorize for human consumption right now.

On Wednesday, we covered the overreaction by a few important online sources to an International Journal of Biological Sciences article claiming to find “signs of toxicity” in three varieties of genetically modified (GM) corn produced by Monsanto. We posted some caveats that made us uneasy about the study, such as the funding sources, the unknown quality of the journal, and the fact that the toxicity claims rely on reinterpreting statistical data that Gilles-Eric Séralini and his coauthors themselves note is not as robust as it needs to be.

Karl Haro von Mogel, a University of Wisconsin Ph.D. student who works with Pamela Ronald (the GM expert we quoted in our last post), responded with some other problems he has on this study. He has a blog post of his own (in which he gets hopping mad at coverage that attributed organ damage, organ failure, or even cancer to the rats in the study). But here are the major issues he points out to DISCOVER:

1. Cherry-picking. “They were picking out about 20–30 significant measurements out of about 500 for one of the sets of data they analyzed,” Haro von Mogel tells DISCOVER. “At the 95% significance level, you would expect that 5% of the observations would show a significant difference due to chance alone, which is what happened.” In other words, one would expect to get some alarming results in approximately 25 out of the 500 of the measurements, which is indeed what they found. “Picking apart what seems to be normal background variability seems to me to be data dredging.”

Séralini: We have not  chosen the significant measurements, we have listed all the parameters  disturbed, all indicated by stars (see Tables joines), there are 20 on 60 for  NK603, 15/60 for MON 810 and 23/60 for MON 863 (other paper published in  2007). This is a lot, concentrating mostly on liver and kidneys, the major  organ reacting in case of chemical intoxication by food.

One must understand that there are the only  blood mammalian analyses allowing the commercialization of these GMOs in the  world, these tests lasting only three months and kept secret for the crude  data before our study.

(more…)

Few things bring out the hyperbole like genetically modified organisms (GMOs), and that was true again with a study making the rounds yesterday and today.

In the International Journal of Biological Studies, a team examined three genetically modified corn varieties created by Monsanto. The study’s authors say they see evidence of possible toxicity to the kidney and liver, “possibly due to the new pesticides specific to each GM corn.” However, the findings became over-hyped headlines like the Huffington Post’s “Monsanto GMO Corn Linked to Organ Failure, Study Reveals.”

That’s a pretty big leap from the not entirely convincing finding of a potentially questionable study. What actually happened is that the research team, led by Gilles-Eric Séralini, re-analyzed data from tests that Monsanto scientists themselves conducted on rats eating these three varieties of corn—data that, to be fair, the team had to scratch and claw and sue to get their hands on. In their statistical analysis, Séralini’s team says that Monsanto interpreted its own data incorrectly, and that its new analysis shows potential for toxicity.

(more…)

Hot on the heels of the story of lab-built red blood cells that DISCOVER covered on Tuesday, a different team of scientists have announced another step forward. Bioengineer Erin Lavik announced that her team built synthetic platelets that, when given intravenously to rodents, could slow their bleeding after a cut. The study appears in Science Translational Medicine.

Your normal platelets exist in the bloodstream and use proteins to bind together and close off the bleeding when you get a cut. Lavik’s synthetic version is a nanoparticle that her team injected into the rodents intravenously. The synthetic platelets augment this process, bonding with natural blood platelets and acting as a nanostructure boosting the natural platelets’ ability to form a solid barrier that stops bleeding [Popular Science]. The rodents with synthetic platelets stopped bleeding 23 percent faster than those without.

(more…)

They may look simple, but our red blood cells are the sophisticated result of evolution. So to create new ways to study our bodies and perhaps even disperse drugs to different organs and body parts, scientists played copycat. A team of researchers announced this week that they have developed synthetic red blood cells that mimic our natural ones in both form and function. They describe their findings in the Proceedings of the National Academy of Sciences.

To make red blood cells in the lab, study leader Samir Mitragotri and colleagues started with spheres of biodegradable polymer. They then exposed the spheres to isopropanol, which collapsed them into the discoid shape characteristic of red blood cells. The researchers then layered proteins — either albumin or hemoglobin — onto the doughnut-shaped disks, cross-linked the proteins to give them extra strength and stability, and finally dissolved away the PLGA template to leave only a strong but flexible shell [The Scientist].

(more…)

In the not too distant future, testing for certain cancers may be completed in less time than it takes to watch an episode of Scrubs.  A new portable device, expected to be about the size of a paperback book, works by detecting biomarkers in the blood, substances that suggest that a patient is diseased. The sensor, which uses nanotechnology, is so accurate that it could pick up a grain of salt in a swimming pool, claim the researchers [Telegraph]. With just a small amount of blood and 20 minutes, doctors can have an electronic read out of biomarker concentrations at their fingertips. The research, led by Mark Reed at Yale University,  may lead to quick, easy, and low-cost cancer tests.

Reed says the technology would be ideal for measuring lung cancer biomarkers in a phlegm sample, or colon or ovarian cancer biomarkers in a blood sample, making their technology the first to measure biomarkers from normal samples of bodily fluids. Previous technologies work in much the same way, but can only detect biomarkers in purified solutions, not the real thing — meaning fluid samples from patients [U.S. News and World Report]. The applications aren’t limited to cancer biomarker measurements; the researchers say they could also measure cardiovascular disease biomarkers in small blood samples. The scientists have published their research in the journal Nature Nanotechnology.

Related Content:
80beats: Nanoparticles + Stem Cells = Faster Healing Wounds
80beats: Golden Nanocages Could Deliver Cancer Drugs to Tumors
DISCOVER: The Era of Nanoparticle Drugs Begins With Erection Cream

Image: Mark Reed / Yale University

DeCode Genetics, a genome sequencing and drug development company, found out the hard way that predicting disease risk simply by reading someone’s genes isn’t so straightforward. On Tuesday, deCode filed for chapter 11 bankruptcy protection in Delaware. The company’s financial problems have also raised some troubling questions about genetic privacy.

DeCode’s mission was to uncover genetic risk factors for common diseases and to develop personal genome scans so individuals could learn their risk. DeCode quickly became the leader in the worldwide race to identify the causes of common disease. The company’s researchers discovered mutations linked to schizophrenia, heart disease, diabetes, prostate cancer and many other illnesses. Its approach was to identify the mutations first in Icelanders and then to confirm them in other populations [The New York Times]. Iceland was seen as an ideal spot for genetic studies, because the population was fairly isolated and the country has excellent medical and genealogical records. However, the company’s early successes did not translate into dollars, in part because the mutations they found only account for a small percentage of the overall incidence of a given disease.

(more…)