foxtongue: (26th birthday)
Sally Adee, a science writer lucky enough to try a DARPA experiment that uses targeted electrical stimulation of the brain during training exercises to induce flow state for a New Scientist article, has some really fascinating things to say about what it was like:
The experience wasn't simply about the easy pleasure of undeserved expertise. When the nice neuroscientists put the electrodes on me, the thing that made the earth drop out from under my feet was that for the first time in my life, everything in my head finally shut the fuck up.

The experiment I underwent was accelerated marksmanship training on a simulation the military uses. I spent a few hours learning how to shoot a modified M4 close-range assault rifle, first without tDCS and then with. Without it I was terrible, and when you're terrible at something, all you can do is obsess about how terrible you are. And how much you want to stop doing the thing you are terrible at.

Then this happened:

The 20 minutes I spent hitting targets while electricity coursed through my brain were far from transcendent. I only remember feeling like I had just had an excellent cup of coffee, but without the caffeine jitters. I felt clear-headed and like myself, just sharper. Calmer. Without fear and without doubt. From there on, I just spent the time waiting for a problem to appear so that I could solve it.

It was only when they turned off the current that I grasped what had just happened. Relieved of the minefield of self-doubt that constitutes my basic personality, I was a hell of a shot. And I can't tell you how stunning it was to suddenly understand just how much of a drag that inner cacophony is on my ability to navigate life and basic tasks. [...]

Me without self-doubt was a revelation. There was suddenly this incredible silence in my head; I've experienced something close to it during 2-hour Iyengar yoga classes, but the fragile peace in my head would be shattered almost the second I set foot outside the calm of the studio. I had certainly never experienced instant zen in the frustrating middle of something I was terrible at. There were no unpleasant side effects. The bewitching silence of the tDCS lasted, gradually diminishing over a period of about three days. The inevitable reintroduction of self-doubt and inattention to my mind bore heartbreaking similarities to the plot of Flowers for Algernon.

I hope you can sympathize with me when I tell you that the thing I wanted most acutely for the weeks following my experience was to go back and strap on those electrodes. I also started to have a lot of questions. Who was I apart from the angry little bitter gnomes that populate my mind and drive me to failure because I'm too scared to try? And where did those voices come from? Some of them are personal history, like the caustically dismissive 7th grade science teacher who advised me to become a waitress. Some of them are societal, like the hateful ladymag voices that bully me every time I look in a mirror. Invisible narrative informs all my waking decisions in ways I can't even keep track of.

What would a world look like in which we all wore little tDCS headbands that would keep us in a primed, confident state free of all doubts and fears? Wouldn't you wear the shit out of that cap? I certainly would. I'd wear one at all times and have two in my backpack ready in case something happened to the first one.
foxtongue: (geigerteller)
Novel technology could potentially seek out cancer cells and cause them to self-destruct:

Using the DNA origami method, in which complex three-dimensional shapes and objects are constructed by folding strands of DNA, Douglas and Bachelet created a nanosized robot in the form of an open barrel whose two halves are connected by a hinge. The DNA barrel, which acts as a container, is held shut by special DNA latches that can recognize and seek out combinations of cell-surface proteins, including disease markers. When the latches find their targets, they reconfigure, causing the two halves of the barrel to swing open and expose its contents, or payload. The container can hold various types of payloads, including specific molecules with encoded instructions that can interact with specific cell surface signaling receptors.

Douglas and Bachelet used this system to deliver instructions, which were encoded in antibody fragments, to two different types of cancer cells -- leukemia and lymphoma. In each case, the message to the cell was to activate its "suicide switch" -- a standard feature that allows aging or abnormal cells to be eliminated. And since leukemia and lymphoma cells speak different languages, the messages were written in different antibody combinations.

"We can finally integrate sensing and logical computing functions via complex, yet predictable, nanostructures -- some of the first hybrids of structural DNA, antibodies, aptamers and metal atomic clusters -- aimed at useful, very specific targeting of human cancers and T-cells," said George Church, Ph.D., a Wyss core faculty member and Professor of Genetics at Harvard Medical School, who is Principal Investigator on the project.
foxtongue: (Default)
Schizophrenia has long been blamed on bad genes or even bad parents. The real culprit, they claim, is a virus that lives entwined in every person's DNA.

Sixty million years ago, a lemurlike animal—an early ancestor of humans and monkeys—contracted an infection. It may not have made the lemur ill, but the retrovirus spread into the animal’s testes (or perhaps its ovaries), and once there, it struck the jackpot: It slipped inside one of the rare germ line cells that produce sperm and eggs. When the lemur reproduced, that retrovirus rode into the next generation aboard the lucky sperm and then moved on from generation to generation, nestled in the DNA. “It’s a rare, random event,” says Robert Belshaw, an evolutionary biologist at the University of Oxford in England. “Over the last 100 million years, there have been only maybe 50 times when a retrovirus has gotten into our genome and proliferated.” [...]

Through this research, a rough account is emerging of how HERV-W could trigger diseases like schizophrenia, bipolar disorder, and MS. Although the body works hard to keep its endogenous retroviruses under tight control, infections around the time of birth destabilize this tense standoff. [...]

The first, pivotal infection by toxoplasmosis or influenza (and subsequent flaring up of HERV-W) might happen shortly before or after birth. That would explain the birth-month effect: Flu infections happen more often in winter. The initial infection could then set off a lifelong pattern in which later infections reawaken HERV-W, causing more inflammation and eventually symptoms. This process explains why schizophrenics gradually lose brain tissue. It explains why the disease waxes and wanes like a chronic infection. And it could explain why some schizophrenics suffer their first psychosis after a mysterious, monolike illness.
foxtongue: (wires)
Scott and Scurvy:
I had been taught in school that scurvy had been conquered in 1747, when the Scottish physician James Lind proved in one of the first controlled medical experiments that citrus fruits were an effective cure for the disease. From that point on, we were told, the Royal Navy had required a daily dose of lime juice to be mixed in with sailors' grog, and scurvy ceased to be a problem on long ocean voyages.

But here was a Royal Navy surgeon in 1911 apparently ignorant of what caused the disease, or how to cure it. Somehow a highly-trained group of scientists at the start of the 20th century knew less about scurvy than the average sea captain in Napoleonic times. Scott left a base abundantly stocked with fresh meat, fruits, apples, and lime juice, and headed out on the ice for five months with no protection against scurvy, all the while confident he was not at risk. What happened? [...]

In the second half of the nineteenth century, the cure for scurvy was lost. The story of how this happened is a striking demonstration of the problem of induction, and how progress in one field of study can lead to unintended steps backward in another.

An unfortunate series of accidents conspired with advances in technology to discredit the cure for scurvy. What had been a simple dietary deficiency became a subtle and unpredictable disease that could strike without warning. Over the course of fifty years, scurvy would return to torment not just Polar explorers, but thousands of infants born into wealthy European and American homes. And it would only be through blind luck that the actual cause of scurvy would be rediscovered, and vitamin C finally isolated, in 1932.

Also: Vitamin D crucial to activating immune defenses. Copenhagen scientists have proven that without sufficient intake of the vitamin, the killer cells of the immune system – T cells – will not be able to react to and fight off serious infections in the body.
foxtongue: (snow)
via jwz:

Hybrid hearts could solve transplant shortage
"It's amazing, absolutely beautiful," says Doris Taylor, describing the latest addition to an array of tiny thumping hearts that sit in her lab, hooked up to an artificial blood supply. The rat hearts beat just as if there were inside a live animal, but even more remarkable is how each one has been made: by coating the stripped-down "scaffolding" of one rat's heart with tissue grown from another rat's stem cells.

The idea is fairly simple: take an organ from a human donor or animal, and use a mild detergent to strip away flesh, cells and DNA so that all is left is the inner "scaffold" of collagen, an "immunologically inert" protein. Add stem cells from the relevant patient to this naked shell of an organ and they will differentiate into all the cells the organ needs to function without inducing an immune response after transplant, or any new infections.

Although Taylor only added stem cells to the hearts, these cells differentiated into many different cells, in all the correct places, which is the best part of using decellularised scaffolds. The stem cells transformed into endothelial cells in the ventricles and atria, for example, and into vascular and smooth-muscle cells in the spaces for blood vessels, just as in a natural heart. Taylor thinks this happened because she pumped blood and nutrients through the organ, producing pressure in each zone which helps to determine how cells differentiate there.

But chemical, as well as mechanical, cues seem to have guided differentiation. Taylor has evidence that growth factors and peptides remained anchored to the scaffold even after the flesh was washed off. These chemicals likely signalled to the stem cells, indicating how many should migrate to which areas and what to change into in each zone. "Our mantra is to give nature the tools and get out of the way," she says.
Also: Stem cells used to restore sight
The idea to team stem cells with contact lenses came from an observation that stem cells from the cornea stick to contact lenses. To obtain the stem cells, Dr Watson took less than a millimeter of tissue from the side of each patients' cornea. Working with colleagues at POWH and UNSW, he cultured stem cells from the tissue in extended wear contact lenses.

Within 10 to 14 days the stem cells began to attach to the cornea, replenishing damaged cells. Satisfied that the stem cells were doing their job, Dr Watson removed the lenses and the patients have been seeing with new eyes for the last 18 months.

SCIENCE!!

Mar. 2nd, 2009 11:24 am
foxtongue: (dream machine)
Scientists have found a way to make an almost limitless supply of stem cells that could safely be used in patients while avoiding the "ethical" dilemma of destroying embryos:
In a breakthrough that could have huge implications, British and Canadian scientists have found a way of reprogramming skin cells taken from adults, effectively winding the clock back on the cells until they were in an embryonic form.

...

Because the cells can be made from a patient's own skin, they carry the same DNA and so could be used without a risk of being rejected by the immune system.

Scientists showed they could make stem cells from adult cells more than a year ago, but the cells could never be used in patients because the procedure involved injecting viruses that could cause cancer. Overcoming the problem has been a major stumbling block in efforts to make stem cells fulfil their promise of transforming the future of medicine.

Now, scientists at the universities of Edinburgh and Toronto have found a way to achieve the same feat without using viruses, making so-called induced pluripotent stem (iPS) cell therapies a realistic prospect for the first time.

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