Blogs / 80beats

In a pioneering new treatment, doctors created a tailor-made new windpipe for a woman out of donor tissue and the woman’s own stem cells, and say the new, transplanted trachea has been accepted by the woman’s immune system as a natural part of her body without the use of powerful immune-suppressing drugs. Martin Birchall, one of the surgeons, said the transplant showed “the very real potential for adult stem cells and tissue engineering to radically improve their ability to treat patients with serious diseases. We believe this success has proved that we are on the verge of a new age in surgical care” [The New York Times]. Similar treatments could soon be tried on transplants of other hollow organs, like the bowel, bladder, and reproductive tract, he said.

The 30-year-old patient, Claudia Castillo, had failing airways and severe shortness of breath due to a bout with tuberculosis. By March of this year, Castillo’s condition had deteriorated to the point where she was unable to care for her children. Removing a lung was one treatment option, which would have allowed her to live, but seriously impaired her quality of life [Forbes.com]. She opted instead for this experimental treatment, in which doctors took a piece of trachea from an organ donor and transformed it into a structure that now appears native to her body.

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Thousands of Gulf War veterans who complained of memory and concentration problems, rashes, headaches, and muscle pain following their return from Kuwait and Iraq were suffering from a real illness and weren’t just feeling the aftereffects of combat stress, according to a new congressionally mandated report. The report broke with most earlier studies by concluding that two chemical exposures were direct causes of the disorder: the drug pyridostigmine bromide, given to troops to protect against nerve gas, and pesticides that were used — and often overused — to protect against sand flies and other pests [Los Angeles Times].

One-quarter of the 700,000 U.S. troops who took part in Operation Desert Storm have reported symptoms of Gulf War Syndrome, according to the report, which fails to identify any cure for the malady. It also notes that few veterans afflicted with Gulf War illness have recovered over time [CNN]. The report calls for at least $60 million in new federally funded research on the syndrome and potential treatments.

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A controversial proposal to switch the U.K.’s current system of voluntary organ donation to a system of “presumed consent” was rejected by the UK Organ Donation Taskforce, which said the change would not increase organ donations and could damage patient-doctor as well as donor-recipient relations. Presumed consent would designate everyone as an organ donor unless the individual or the family of the deceased opted out; the current system is just the opposite, harvesting organs only from people who opt in to organ donation.

The task force advised against the switch supported by Prime Minister Gordon Brown, the British Medical Association (BMA), and several physician groups. Nevertheless, Brown continues to support a presumed consent system. “While they are not recommending the introduction of a presumed consent system, as I have done, I am not ruling out a further change in the law,” he said [The Guardian].

The U.K. has one of Europe’s lowest rates of organ donation. Of an estimated 8,000 people on waiting lists for organ transplants, only about 3,000 receive transplants every year, and 1,000 die while waiting for a transplant. Vivienne Nathanson, the BMA’s Head of Science and Ethics, said presumed consent was not a panacea, but was likely to result in a 10 to 15 per cent increase in donated organs, if sufficient surgeons, intensive care beds and transplant coordinators were put in place. She said it would also encourage families to discuss their views, and make their wishes clear before death: “We know that the majority of the population want to be organ donors, but only 25 per cent are on the register” [Times Online].

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The germ-fighting power of bleach lies in its ability to unravel cellular proteins, according to a new study. Researchers at the University of Michigan report that the active ingredient in bleach, hypochlorous acid, irreparably alters the three-dimensional structure of proteins in living cells—to fatal effect. They also found that some bacteria possess a special protein that can somewhat counter the ravages of hypochlorous acid. The findings clear up a hitherto murky understanding of how the common household cleaner does its job. “Everyone knew that bleached worked, and that was enough,” says [researcher Ursula Jacob]. “Few really cared how it worked” [Nature News].

In fact, Jacob’s team didn’t set out to answer that question either. They were studying a bacterial protein known as heat shock protein 33 (Hsp33) that helps other proteins maintain their proper shapes. Hsp33 is activated in times of stress, such as when the bacteria is exposed to high temperatures. “At high temperatures, proteins begin to lose their three-dimensional molecular structure and start to clump together and form large, insoluble aggregates, just like when you boil an egg,” said study lead author Jeannette Winter… Like a boiled egg, those proteins can never revert to their previous state, and the stressed cells eventually die [LiveScience.com].

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The issue of the First Dog came to national attention with Barack Obama’s first press conference as President-elect, when he announced that the lucky puppy would have to be hypoallergenic due to older daughter Malia’s allergies. Since then, nominations for First Dog have come from all sides, even from foreign countries: Peru has offered to send a Peruvian Hairless Dog, prized by Incan kings, to the Obamas. But all the buzz has prompted a reality check from the American Academy of Allergy Asthma & Immunology (AAAAI), which released a statement today reminding people that there is no such thing as a truly hypoallergenic dog.

Avoiding dog allergies completely may not be an option. It’s a misconception that dog allergies are caused by the dog’s hair. Allergies are caused by protein from the animal’s dander, which can be found in dead skin cells, saliva and urine. These microscopic proteins travel through the air and are inhaled, triggering an allergic reaction in, well, quite a few people [Los Angeles Times]. Studies suggest there are about 10 million Americans who suffer from dog allergies, but sensitivity varies and some people may do fine with certain breeds that are more allergy-friendly. These breeds may produce less dander or are groomed more often to keep dander at bay. Breeds often considered allergy-friendly include poodles, Kerry blue terriers, schnauzers, bichons and lhasa apsos.

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In a remarkable announcement, German researchers have declared that they “functionally cured” a patient of AIDS, eradicating all traces of the virus from his body. The feat was accomplished with a bone marrow transplant from a donor who had a genetic resistance to the virus, and researchers say that 20 months later they can find no trace of the virus in the patient’s blood, bone marrow, or organ tissue.

But the accomplishment shouldn’t be taken as a sign that a cure for the 33 million people living with AIDS is around the corner, researchers are hasty to add. Professor Rodolf Tauber from the [German] clinic said: “This is an interesting case for research. But to promise to millions of people infected with HIV that there is hope of a cure would not be right” [BBC News]. Reasons for this caution include the small number of potential donors with the HIV-resistant mutation, and the difficulty and expense of bone marrow transplants.

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A new intelligent pill designed by Philips, the Dutch electronics company, promises to deliver medicine in the right place, at the right time, inside your body. The company, best known for consumer products like webcams and wireless headphones, is packing some of the same technology into the new pill, known as the iPill. Containing a microprocessor, battery, wireless radio, pump and a reservoir for medication, the inch-long capsule is designed to treat digestive tract disorders such as Crohn’s disease and ulcerative colitis [Times Online].

Once swallowed, the iPill allows researchers to keep track of its precise location through a wireless transmitter. It sends dispatches about the temperature and acidity of its surroundings to an outside receiver as it travels through the GI tract over the course of a day or two. The acidity, measured by pH, of the gut decreases as the pill gets further from the stomach, and that allows researchers to pinpoint the place where the drug is needed [San Francisco Chronicle]. Researchers can pre-program drug release when certain conditions are met or cue the drug release using a remote controller.

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In yet another warning signal of the toll that childhood obesity will take on health and health care budgets, a small study has shown that overweight kids as young as 10 years old have the thickened arteries of 45-year-olds. Researchers say the findings raise the possibility that these kids could develop serious heart disease in their 20s or 30s. “There’s a saying that ‘you’re as old as your arteries,’ meaning that the state of your arteries is more important than your actual age in the evolution of heart disease and stroke,” said [lead researcher] Dr Geetha Raghuveer [Telegraph].

The findings, while preliminary, should serve as a serious alarm bell in the United States, where about one-third of children are overweight and almost one-fifth are obese. Many parents think that “baby fat” will melt away as kids get older. But research increasingly shows that fat kids become fat adults, with higher risks for many health problems. “Obesity is not benign in children and adolescents,” said Dr. Robert Eckel, a former heart association president [AP].

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You may not want to think about what goes into your fast food, but a new study may at least put your overactive imagination to rest: It’s mostly corn. The researchers analyzed hamburgers, chicken sandwiches, and fries from McDonald’s, Burger King, and Wendy’s and determined that nearly all of them could be traced to the corn industry– in the form of corn feed or corn-based oil. “If you put any money into fast food, it all goes back to corn, everything. The first step to making hamburgers is making an ear of corn,” said Hope Jahren, lead author of the study [Des Moines Register].

The researchers traveled to Los Angeles, San Francisco, Denver, Detroit, Boston and Baltimore, purchasing feasts of fast food at multiple restaurants in each city. Samples of beef, chicken, and fries were then ground up and analyzed for levels of isotopes. Specifically, they were looking for carbon-13, which is a unique signature of corn, and nitrogen-15, which is found in fertilizers and animal excrement. Based on the high levels of carbon and nitrogen isotopes found in the meat products, the authors claim that the cattle and poultry were predominantly fed corn, which makes them as fat as possible in as short a time as possible, and were raised in extreme confinement [Forbes.com], keeping the animals in close contact with their own excrement. The high nitrogen-15 content also suggests the corn fields were heavily fertilized with nitrogen-based fertilizers.

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Scientists say they have bred super immune cells that are able to recognize and destroy many variants of HIV-infected cells. The news comes after a bleak year for AIDS research that saw the failure of the Merck HIV vaccine trial and the cancellation of another. “I think the field as a whole has been taking a step back and thinking we need some different ideas all together,” [New Scientist] said immunologist Philip Goulder.

The researchers’ novel idea was to create a mutant type of immune cells, called T-cells, that would target SL9, a protein that is part of HIV and also appears on the surface of HIV-infected cells. They started with particularly strong T-cells taken from a patient who had resisted HIV infection. “When we tested the T cells from this patient, it looked as if he was responding to a number of those variants that normally escape the immune system,” [The Guardian] said researcher Brent Jakobsen. Through a process of directed evolution, the researchers selected for T-cell mutants that had receptors enhanced to recognize and latch onto SL9. In Nature Medicine [subscription required], the researchers report that in lab cultures of human cells, the souped-up T-cells easily destroyed HIV-infected cells and even recognized tricky variants of the SLP9 protein.

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Injury to nerve cells in the brain and spinal cord, once considered permanent, may be reversible after all. A pair of new studies demonstrate how to override two biological mechanisms that prevent damaged cells of the central nervous system from regrowing. The first obstacle are genes that prevent nerve growth and the second are chemical signals that repress nerve growth.

In the first study, published in Science [subscription required], Harvard researchers identified a gene, PETN, that inhibits the major growth pathway in nerve cells. They created genetically modified “knock-out” mice that lacked the gene. Normally, axons in the optic nerve of adult mice do not regenerate when crushed—and worse yet, about 80% of the neurons with severed axons die. But in mice lacking PTEN, 50% of neurons survived and about 10% of axons in the optic nerve regrew—as far as 4 millimeters in 28 days. “To have any manipulation that can make these axons grow from where they were severed near the retina all the way down the optic nerve is just amazing,” [ScienceNOW Daily News] commented neurobiologist Ben Barres.

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The standard lab equipment used by scientists to study subtle chemical reactions and examine biological processes may be compromising their results. A new study found that disposable plastic tubes, pipette tips, and culture plates contain compounds that can leach into common solvents. The study is the first to show how thousands of scientists worldwide may be unwittingly contaminating their experiments with plastic lab equipment. “People are clearly aware that plastics can cause problems. Quite remarkably, nobody appears to have done what we were forced to do,” says co-author Andrew Holt [New Scientist].

Holt was studying the effect of drugs on the enzyme monoamine oxidase B (MAO-B) when he noticed strange fluctuations in the results. “We were banging our head against the wall. Finally, we realized that the plastics must be involved in the issue” [Bloomberg]. Holt washed out his equipment with water, methanol or dimethylsulphoxide (DMSO), then analysed what chemicals had leached into the solvents using mass spectrometry. Reporting in Science, Holt and his colleagues show that the plastic tubes they were using were leaching the disinfectant di(2-hydroxyethyl)methyldodecylammonium (DiHEMDA) into water and the lubricant oleamide into methanol and DMSO [Nature News]. Though the amount of leaching varies, some of the plastic equipment produced contaminant concentrations of several hundred parts per million. “The compounds that leached out of the plastic were remarkably potent inhibitors,” [said Holt]. “We were getting variability caused by these leachates that could completely mask the effects of the drugs” [Nature News].

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The European Commission has proposed a ban on medical research performed on our species’ closest relatives, the great apes. The pan-European initiative would extend a ban already in force in Austria, Great Britain, the Netherlands, and Sweden across the entire 27-member bloc. The ban, however, would not greatly affect current research, because no testing has been carried out on great apes in the EU for the past six years [The Scientist]. Nevertheless, the proposal [pdf] has received mixed reviews from both the scientific community, who fear excessive red tape, and animal rights groups, who say the ban does not go far enough.

If approved, the ban would prohibit researchers from using great apes, including chimpanzees, bonobos, gorillas, and orangutans, to test scientific “procedures,” although behavioral studies will still be allowed. There will also be exceptions for research that could save a great ape species threatened with extinction and in the case of a serious pandemic that affects humans. The proposal also affects research on other animals, stressing the “3Rs” of reducing the number of animals used, refining techniques to lessen pain and discomfort, and replacing animal studies with alternatives [ScienceNOW Daily News]. Some 12 million vertebrate animals are used each year in experiments throughout the 27-nation bloc — half for drug development and testing, a third for biology studies and the rest for cosmetics tests, toxicology and disease diagnosis [Reuters].

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Dosing menopausal women with testosterone may be the key to helping those with low libidos get back in the mood, according to a new study. Proctor & Gamble Pharmaceuticals has published the results of a new trial of their testosterone patch, called Intrinsa, and say the results are encouraging for frustrated older women seeking a “Viagra for women.” However, nagging safety concerns are likely to keep the drug off the market in the United States for some time to come (although the drug is already on sale in Europe): During the new study, four of the test subjects using the patch developed breast cancer.

The 52-week study included 814 women with sexual desire disorder, characterized by troublesome low sexual desire or function…. The women were asked to keep sexual encounter diaries, and researchers used other established measures to assess sexual response during the six-month evaluation phase of the study. They found that compared to placebo users, the women who used the 300 microgram patch reported significant improvements in sexual functioning, including desire, arousal, orgasm, and pleasure [WebMD].

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For the first time researchers have sequenced the complete genome of a cancer cell, and they say the process turned up eight previously unknown genetic mutations that played a role in the patient’s terminal leukemia. As it gets cheaper and easier to decode entire genomes, as opposed to just checking “usual suspect” stretches of DNA, doctors hope to decode the genomes of many different types of cancer. Eventually, researchers say cheap techniques may allow doctors to study the cancer genomes of individual patients.

Lead researcher Richard Wilson said he hoped that in 5 to 20 years, decoding a patient’s cancer genome would consist of dropping a spot of blood onto a chip that slides into a desktop computer and getting back a report that suggests which drugs will work best.“That’s personalized genomics, personalized medicine in a box,” he said. “It’s holy grail sort of stuff, but I think it’s not out of the realm of possibility” [The New York Times].

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