biology
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Experimental stem cell treatment causes woman to grow parts of a nose on her spine
Stem cells are seen as one of modern medicine's most promising magic bullets, but that doesn't mean that we understand them. A paralyzed woman from the US has learned this the hard way, after an experimental treatment caused her to grow a nose-like tumor on her back. The unnamed person took part in a trial whereby stem cells from her nose were applied to her spine in the hope that it could repair the nerve damage that led to her paralysis. Unfortunately, the treatment was unsuccessful and, eight years later, the subject found worsening pain in that same area. When surgeons operated, they found a tumor comprised of nasal tissue that was producing a thick substance that was remarkably close to mucus.
$17 million research prize will go towards drug-resistant bacteria studies
Antibiotic resistant bacteria is one of the greatest public health threats of our age, because we're heading for a world where common maladies can overcome any drug that we throw at them. That's why it's been chosen as the goal for this year's Longitude Prize. Like the original, awarded in 1765 to a carpenter who built the first chronometer, a £10 million ($17 million) bounty will be offered to anyone who believes that they can come up with a solution to the problem.
Scientists may have worked out how to defeat antibiotic-resistant superbugs
It's been known for a while that bacteria are rapidly becoming immune to the current range of antibiotics humanity has available. That's why it's harder to get hold of pills now than it was a few years ago, simply because if we don't learn to get by without them, we'll probably all die of some hideous mutated strain of MRSA in a few years' time. Rather than simply developing new antibiotics to throw at the problem, however, a team of researchers from the University of East Anglia and the Diamond Light Source in Oxford claims to have discovered a way to undermine a bacteria's ability to develop drug-resistance in the first place -- causing them to wither and die before it even becomes a problem.
Researchers are using 3D printers to make blood vessels
There has been talk of printing blood vessels for a few years, but it's tricky to make tissue that fits the complex shapes of a human body while remaining effective. However, a research team at Brigham and Women's Hospital may have licked that problem: they've 3D printed vessels using a new technique that allows for intricate yet capable designs. Their process first prints agarose (sugar-based molecule) fibers as templates for the vessels, and then covers that in jelly-like hydrogel to produce a cast. Since the agarose is sturdy, scientists can pull it out to create channels without damaging any cells inside the gel; the resulting vessels are much better at transporting liquid and otherwise behaving like the real deal.
This is what brain synapses look like in 3D
Many know that brains are inherently complex things; there are trillions of synapses converting chemical and electrical signals in a human mind. However, did you know that even those synapses are very complex? If not, it should be perfectly clear now. German scientists have used a mix of extremely high-resolution microscopes (both electron and fluorescent), mass spectrometry and protein detection to create a super-detailed 3D map of a synapse in a rat's brain. It's almost like a miniscule city -- those dots you see represent 300,000 proteins, and only a tiny portion (the glowing red patch at the bottom) is transmitting chemicals.
MIT can map the activity of every neuron in an animal's brain
Scientists have long yearned for a neuron-by-neuron illustration of brain activity; get that and you can see exactly what drives an animal's thoughts and reflexes. MIT may make those wishes come true, as it just revealed a system that produces a complete 3D neural activity map. The discovery revolves around a light field microscope (which refracts light to create a 3D image) that's optimized for looking at the electrical pulses of each neuron, right down to the millisecond time level. So far, researchers have created videos showing what's happening within the entire nervous system of a c. elegans worm, and the brain of a zebrafish larva.
Artist stuffs Wikipedia into apple DNA to create real trees of knowledge
If DNA is code, and code can be art, then DNA can be art... right? Harvard artist in residence Joe Davis certainly thinks so. He's working on a project, Malus Ecclesia, that will insert Wikipedia entries into the non-essential genetic strands of apples. The effort will translate English Wikipedia articles to DNA's four nucleotide letters (A, C, G and T) and use bacteria to insert the resulting text into saplings. When the saplings are grafted on to apple stock and grow up, they'll bear fruit with that genetic data (and therefore the articles) intact, producing very real trees of knowledge.
Scientists create 'semi-synthetic' living cells with extra DNA letters
It turns out that your biology teacher (and a certain 1997 sci-fi flick) got something wrong -- DNA isn't necessarily limited to four letters. Scripps Research Institute scientists tell Wired that they've created living cells which include two artificial letters (that is, nucleotides) in their genetic code in addition to the naturally occurring A, C, G and T. The researchers' primary obstacle was making sure these nucleotides cooperated with the enzymes that copy and transcribe DNA; after that, it was just a matter of getting some E. coli bacteria to accept and propagate the newly augmented sequences.
Scientists can trace your ancestors to within 30 miles using DNA
You might know where your forebears lived a few generations prior, but how about the exact village they came from -- 1,000 years ago? Thanks to DNA sequencing, it's now possible to find that out in many cases according to researchers from the University of Sheffield in the UK. The aptly-named GPS or Geographic Population Structure tool was modeled using more than 100,000 DNA signatures called AIMs (ancestry-informative markers). Since those are often typical to geographic regions, the researchers were able to pinpoint where subjects came from, even if they moved around later (see the video below). During a Sardinian study, for instance, a quarter of the test subject were located to their exact villages and the remainder to within 31 miles. You can even try it for yourself by getting a simple DNA test from 23andme or ancestry.com (for $100-200), then uploading the results to the GPS tool.
Praying mantises get extra-tiny 3D glasses to test their vision
While 3D video may not be very popular these days, someone's still wearing 3D glasses -- or rather, something. Newcastle University scientists are outfitting praying mantises with very small 3D eyewear to test their depth perception, which is unique in the insect world; most species are limited to 2D. The researchers want to see if the bugs are fooled by the effects of a 3D movie like that you'd see in a theater. If they are, we'll know that they evolved 3D vision similar to that of humans and monkeys.
Scientists get much closer to cloning human embryos from adult stem cells
It's relatively easy to clone embryos from the adult stem cells of simpler animals like sheep, but humans have proved challenging. Even an attempt last year only used baby cells. The process just took a gigantic step forward, though, as scientists have finally used an adult human's stem cells to clone a pre-embryonic blastocyst. The process was mostly similar to that for other species: researchers removed the DNA from the nucleus of an unfertilized egg and inserted a skin cell into that egg. From there, the team only needed growth chemicals to develop the stem cells into specific cell types, such as heart tissue.
Researchers create 'programmable' stem cells through stress
Making stem cells in the lab is typically a complicated process, and there isn't much variety in the results without resorting to foreign DNA. However, researchers at both Brigham and Women's Hospital and Japan's RIKEN may have found a way to easily create most any stem cell a doctor would need. Their new technique subjects adult cells to extreme stress, such as oxygen deprivation. The victims that survive the process retreat into a state much like that of an embryonic stem cell; after that, scientists just have to grow the cells in the right environment to get the stem cells they want. It will be a while before the team tests this process with humans, but it could lead to stem cells tailor-made for specific patients -- you'd only have to provide a blood sample to get replacement tissues.
Digitally simulated worm wriggles for the first time (video)
It's relatively easy to simulate life in an abstract sense, but it's tricky to do that cell by cell -- just ask the OpenWorm Project, which has spent months recreating a nematode in software. However, the team recently cleared an important milestone by getting its virtual worm to wiggle for the first time. The project now has an algorithm that triggers the same muscle contractions you'd see in the real organism, getting the 1,000-cell simulation to "swim" in a convincing fashion. There's still a long way to go before OpenWorm has a complete lifeform on its hands, mind you. The group has to introduce code for a nervous system, and performance is a problem -- it takes 72 hours to emulate one-third of a second's worth of activity. If all goes well, though, you'll eventually get to play with the worm through a browser. In the meantime, you can check out the digital critter's motion in a video after the break.
Supreme Court rules that naturally occurring DNA cannot be patented
In a plot twist straight out of Orphan Black, the Supreme Court has ruled that naturally occurring DNA cannot be patented, but synthetic biological material is fair game. The case involved Myriad Genetics, a company specializing in molecular testing, after it tried to patent two genes -- BRCA1 and BRCA2 -- that are often linked to breast and ovarian cancer. The Association for Molecular Pathology filed the suit, arguing that the patent would place undue restrictions on research since only Myriad would be allowed to tinker with those genes. The ruling established that isolating naturally occurring genetic material -- as Myriad did -- wasn't enough to justify legal ownership, but so-called complementary DNA (meaning it's man-made) would be eligible for patenting. Myriad had no comment at the time of this writing, but Sandra Park, an attorney with the ACLU Women's Rights Project said, "Myriad did not invent the BRCA genes and should not control them. Because of this ruling, patients will have greater access to genetic testing and scientists can engage in research on these genes without fear of being sued."
Stanford researchers create genetic transistors, make biologic computing possible
When constructing computer circuits, most folks start with silicon and metal, but not the researchers at Stanford. The boffins in Palo Alto want to build computers out of living tissue, and to that end they've created a biological transistor, called the transcriptor. Transcriptors substitute DNA for semiconductors and RNA for the electrons in traditional transistors -- essentially, the transcriptor controls the flow of a specific RNA protein along a DNA strand using tailored combinations of enzymes. Using these transcriptors, researchers built logic gates to derive true/false answers to biochemical questions posed within living cells. Using these bio-transistors, researchers gain access to data not previously available (like whether an individual cell has been exposed to certain external stimuli), in addition to allowing them to control basic functions like cellular reproduction. This new breakthrough -- when combined with the DNA-based data storage and a method to transmit DNA between cells the school's already working on -- means that Stanford has created all the necessary components of a biologic computer. Such computers would allow man to actually reprogram how living systems operate. Of course, they haven't built a living genetic PC just yet, but to speed up its development, the team has contributed all the transcriptor-based logic gates to the public domain. Looking to build your own biologic computer? A full explanation of the transcriptor awaits below.
Alt-week 1.26.13: quadruple DNA helixes, Byzantine mutants and battling hospital bugs
Alt-week takes a look at the best science and alternative tech stories from the last seven days. In isolation, this week's stories are all pretty notable, but if you put them together, it begins to sound a lot like the plot of a movie. Four-stranded DNA, a database of alien planets, a new super-chemical to kill hospital bugs and a byzantine gamma-radiation blast. You can almost picture the plucky heroine trying to unpick the galactic conspiracy before someone loses an eye -- and if you've already cast weepy Clare Danes in the role, then you've already passed the entry exam to read Alt-week.
Nano-machines built to mimic human muscle could help power cyborgs, keep the OSI budget down
At today's prices, building a Six Million Dollar Man would cost around $31 million. Of course, being a TV show means the Office of Scientific Intelligence doesn't have too many bionic employees, but that might not the case in the future. Nicolas Giuseppone and a team at the Université de Strasbourg and CNRS have created thousands of nano-machines to replicate the movement of human muscle fibers. Weaving them all together, the machines are able to make a coordinated contraction movement that stretches and contracts. For the moment, the supramolecular polymers can only stretch a matter of micrometers, but in the future they could be used to create artificial muscles, small robots or even materials that can move. Hopefully it'll also give us the power to leap tall buildings, so we'll be outside practicing our sound effects.
Alt-week 7.28.12: social mathematics, Pluto's moons and humans-on-a-chip
Alt-week peels back the covers on some of the more curious sci-tech stories from the last seven days. It's a beautiful world we live in. And, while the sweet and romantic part is debatable, strange and fantastic is not. Our universe is one populated by non-planetary celestial bodies with their own non-planetary satellites, high school social hierarchies based on predictable mathematical formulas and military-funded "gut-on-a-chips." It's a weird place filled with weird stories, and we just can't get enough of it. So, what has the last seven days brought us from the fringes of science and tech? Keep reading after the break to find out. This is alt-week.
Robotic legs simulate our neural system, lurch along in the most human-like way so far
We've seen some pretty wonky bipedal robots before, but scientists at the University of Arizona have gone straight to the source -- us -- to make one with a more human-like saunter. It turns out it's not just our skull-borne computer that controls gait: a simple neural network in the lumber area of our spine, called the central pattern generator (CPG), also fires to provide the necessary rhythm. By creating a basic digital version of that and connecting some feedback sensors in the legs, a more natural human stride (without balance) was created -- and on top of that it didn't require the tricky processing used in other striding bots. Apparently this throws light on why babies can make that cute walking motion even before they toddle in earnest, since the necessary CPG system comes pre-installed from birth. That means the study could lead to new ways of stimulating that region to help those with spinal cord injuries re-learn to walk, and produce better, less complex walking robots to boot. Judging by the video, it's a good start, but there's still a ways to go before they can mimic us exactly -- you can watch it after the break.
Researchers create spinal cord connectors from human stem cells, heralding breakthrough
It's taken many years and more than a bit of brainpower, but researchers at the University of Central Florida have finally found a way to create neuromuscular connectors between muscle and spinal cord cells, using only stem cells. Led by bioengineer James Hickman, the team pulled off the feat with help from Brown University Professor Emeritus Herman Vandenburgh, who collected muscle stem cell samples from adult volunteers. After close examination, they then discovered that under the right conditions, these samples could be combined with spinal cord cells to form connectors, or neuromuscular junctions, which the brain uses to control the body's muscles. UCF's engineers say the technique, described in the December issue of the journal Biomaterials, marks a major breakthrough for the development of "human-on-a-chip" models -- systems that simulate organ functions and have the potential to drastically accelerate medical research and drug development. These junctions could also pay dividends for research on Lou Gehrig's disease or spinal cord injuries, though it remains unclear whether we can expect to see these benefits anytime soon.
