In an important step towards creating synthetic life forms, genetics pioneer George Church has produced a man-made version of the part of the cell that turns out proteins, which carry out the business of life. “If you going to make synthetic life that is anything like current life … you have got to have this … biological machine,” Church told reporters in a telephone briefing. And it can have important industrial uses, especially for manufacturing drugs and proteins not found in nature [Reuters].
Church’s team built a functional ribosome from scratch, molecule by molecule. Ribosomes are molecular machines that read strands of RNA and translate the genetic code into proteins. They are exquisitely complex, and previous attempts to reconstitute a ribosome from its constituent parts – dozens of proteins along with several molecules of RNA – yielded poorly functional ribosomes, and even then succeeded only when researchers resorted to “strange conditions” that did not recapitulate the environment of a living cell, Church said [Nature blog]. Next, the researchers want to produce man-made ribosomes that can replicate themselves.
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Researchers have tweaked HIV virus to create a strain that can infect monkeys, and say the development will allow better testing of vaccines and AIDS drugs. Until now, AIDS researchers used monkeys infected with simian immunodeficiency virus, or SIV. The virus is similar to ours, but it’s far from a perfect research tool…. Though SIV and HIV wreak similar havoc on their hosts’ immune systems, drugs affect them differently. While that makes SIV useful for studying how the disease progresses, it’s less useful for studying potential treatments [Wired News].
The new strain of HIV was developed by altering a single gene in the human version to allow it to infect a type of monkey called a pig-tailed macaque [Reuters]. The researchers replaced one HIV gene with the SIV version of the gene, which blocks virus-killing proteins made by the monkey and allows the infection to take hold. Even this altered virus doesn’t make the monkeys very sick, but while animal lovers may see that as a benefit, researchers see it as the final hurdle to overcome.
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Researchers have engineered antibodies that could potentially lead to a cure-all for multiple strains of influenza, including the dangerous H5N1 strain of bird flu, according to a study published in Nature Structural and Molecular Biology. Mice that were infected with bird flu and three days later were injected with the treatment exhibited no symptoms of illness. Whereas existing flu vaccines are able to target only one strain of virus at a time and need to be redeveloped every year, the new research suggests that a single treatment may work against many strains.
For the study, the scientists scoured a library of 27 billion human antibodies to influenza, eventually finding an antibody which inactivated bird flu in cell cultures and when injected into mice. The group then decided to see how the antibody fared against an entirely different subtype of flu—the influenza that killed millions across the globe in World War I. “To our amazement, the antibodies inactivated the 1918 pandemic,” [study author Wayne] Marasco said. Subsequent studies showed the virus could disarm multiple strains of flu [The Scientist]. The treatment is made from a laboratory-produced version of human immune system defenses called monoclonal antibodies. It targets a different part of the flu virus than the body’s naturally produced antibodies [Bloomberg].
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Although the vast majority of the scientific establishment has loudly declared for years that there is no link between autism and childhood vaccinations, some parents with autistic children have persisted in making the claim, and even brought the matter to a special federal court. Now, the judges appointed to rule on the first cases have added their voices to those of the scientists, stating that there is no such link. One of the officials, George Hastings, said the parents had “been misled by physicians who are guilty, in my view, of gross medical misjudgment.” Hastings said that he was deeply moved by the suffering autism imposed on families … but that “the evidence advanced by the petitioners has fallen far short of demonstrating . . . a link” [Washington Post].
The parents had brought their cases to the National Vaccine Injury Compensation Program, which was set up to compensate the very few people who suffer serious side effects from vaccines. Rather than have these victims sue vaccine makers in regular court — potentially putting the manufacturers out of business and jeopardizing a major component of the country’s public health infrastructure — the court set up a “no-fault” system that required victims to prove to a special master only that vaccines harmed them, and not that anyone intentionally caused the harm [Washington Post]. In 2001, parents of children with autism began filing petitions with the program asking for compensation. Of the 12,850 cases ever filed through the program, about 5,535 represented autism cases [AP].
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In an effort to make polio the second infectious disease wiped off the face of the planet, a group of charities and governments has pledged $630 million over five years to bolster vaccination efforts. The new cash infusion is spearheaded by the Bill and Melinda Gates Foundation, which committed $255 million, with Rotary International and the governments of Germany and the United Kingdom promising the rest of the money.
Public health officials point hopefully to the example of smallpox, which was eradicated in 1980 after an unprecedented global campaign, but the recent statistics on polio show how tricky and expensive the endgame can be to eliminate a disease…. The polio vaccine was first created in the 1950s and the disease was quickly killed off in the U.S. and many parts of the world. Strong gains against polio continued through the 1990s but an uptick last year in the number of reported cases has health officials and donors concerned that it could re-infect parts of the world [The Wall Street Journal].
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Flu season is taking a toll on chicken farms across Asia, where new bird flu outbreaks are cropping up from China to India, leading to massive poultry slaughters. Health officials say the chickens are infected with the deadly bird flu strain known as H5N1, but thus far there have been only a few cases of human infection. Two human cases have been reported in Indonesia, one in Cambodia, and in Egypt a 16-year-old girl died of the virus. Yi Guan, a Hong Kong microbiology professor, says the recent spate of cases across the region may not be completely isolated and would likely get worse as winter sets in, when the risks of influenza tend to peak [The Wall Street Journal].
In China, more than 370,000 chickens were culled after an outbreak was announced in the eastern province of Jiangsu. The usual precautions have been imposed: birds have been slaughtered in the surrounding area, farms quarantined and disinfected, and the transport of fowl banned. But no information has been released about the scale of the outbreak – how many birds were found to be carrying the H5N1 strain of the virus and how many of them died [BBC News]. Chinese authorities say migrating birds probably brought the virus to local farms.
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Cancer will be the world’s leading killer by 2010, edging out heart disease for the top spot, according to the latest report by the World Health Organization (WHO). Though cancer rates in the United States have just recently begun to decrease, elsewhere in the world cancer is on a steady rise. Experts cite tobacco, increasingly Western lifestyles, and inadequate medical care as the factors contributing to the cancer epidemic in developing countries. “In the U.S., we pay a lot of attention to cancer trends, and the trend has been encouraging,” says Dr. Richard Schilsky… “But we have forgotten that there is a big wide world out there. Cancer is a global problem” [TIME].
According to the WHO report, 12 million new cases of cancer will be diagnosed this year and 7 million will die from the disease. The group forecast a 1 percent increase globally each year, with emerging economies such as China, Russia and India being hit the hardest [CNN]. The report also projects a 38 percent population increase in less developed countries by 2030. Taken together, that means by 2030 an estimated 20 to 26 million new cases of cancer will be diagnosed annually and 13 to 17 million deaths will be cancer-related.
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Firing new shots in the malaria war, a vaccine still in the testing stage is now a step closer to becoming a public health reality [Science News]. Two field trials in Kenya and Tanzania showed that the experimental drug reduced malaria infections by more than 50 percent in infants and young children; if a final set of trials proves that the vaccine is indeed safe and effective, the vaccine could be ready for use by 2011.
If the phase three trials are successful, it would be “an extraordinary scientific triumph,” said Dr. W. Ripley Ballou, deputy director for vaccines and infectious diseases for the Bill and Melinda Gates Foundation, which helped fund the research. But more importantly,” Ballou added, “it could save millions of children’s lives” [Los Angeles Times]. Malaria kills about 1 million people around the world each year, and most of the victims are children under the age of five.
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This week, South African health minister Barbara Hogan got her country up to speed with the rest of the world with one statement: “We know that HIV causes AIDS” [Time]. The country’s new health minister has been in office for less than a month, but she has already broken with the health policies of the previous government, which questioned the scientific consensus on HIV and AIDS, and discouraged the use of life-saving AIDS drugs.
Her pronouncement at an international AIDS vaccine conference marked the official end to 10 years of denial about the link between HIV and AIDS by former President Thabo Mbeki and his health minister Manto Tshabalala-Msimang. Activists also accused Tshabalala-Msimang of spreading confusion about AIDS through her public mistrust of antiretroviral medicines and promotion of nutritional remedies such as garlic, beetroot, lemon, olive oil and the African potato [AP]. Tshabalala-Msimang earned the nickname “Dr. Beetroot” from frustrated activists for her recommendations.
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Researchers have decoded the genomes of two different malaria parasites that plague people in Southeast Asia and South America, and say the new information will boost efforts to find a vaccine for the mosquito-borne disease. The work builds on the sequencing of the first malaria genome six years ago, when scientists tackled the most deadly malaria parasite, Plasmodium falciparum, which is endemic in Africa. By comparing the genetics of Plasmodium falciparum to that of the newly sequenced species, P. knowlesi and P. vivax, the two teams have begun to identify the different mechanisms by which each species maximizes its chances of evading the host immune system [The Scientist].
P. vivax is the main cause of malaria in Latin America and Southeast Asia, and although it’s rarely deadly researchers say it still causes plenty of misery. It’s also challenging to eradicate because it can lie dormant in the liver for months. “It makes people very sick,” says lead researcher Jane Carlton…. “It can come out of the liver weeks or months after the initial mosquito bite. That makes it a very serious risk to human health.” Vivax malaria is so debilitating that sufferers, most of whom are poor, can’t support themselves or their families. “Vivax is one of the stealth reasons that poor people can’t escape poverty,” says [tropical disease expert] Peter Hotez [USA Today].
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Researchers say they have turned a tobacco plant into a living factory that can produce individualized vaccines to fight a type of cancer known as follicular lymphoma. While similar vaccines have been grown inside animal cells, researchers say this new process is quicker and less expensive, and could carry less risk to the patient, as animal cells might hold unknown viruses [BBC News].
In the new technique, researchers took biopsies from each lymphoma patient and isolated the gene that produces tumor-fighting antibodies, which is slightly different in each person. In each case, they then used a genetically engineered tobacco virus to bring the gene into a tobacco plant, where the plant responded by turning out antibodies. One week later the tobacco leaves were picked and ground into pulp, and the antibodies were extracted. These antibodies are put into a patient newly-diagnosed with the disease, to “prime” the body’s immune system to attack any cell carrying them. If successful, this would mean the body would then recognise and destroy the lymphoma cells [BBC News].
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In a day of mixed results for Alzheimer’s research, researchers found that an experimental vaccine failed to prevent the disease’s crippling dementia, but also noted that a drug once used to treat hayfever “significantly” improves the symptoms of memory loss. The two separate studies were both published in the Lancet [subscription required], and offer a telling reminder that in medical research progress against a disease is rarely straightforward.
The first study treated patients who had already been diagnosed with Alzheimer’s with a vaccine that targeted the protein plaques that clump around brain cells in increasing numbers as Alzheimer’s progresses. The theory was that dementia could be slowed or reversed once the plaques were cleared [HealthDay News]. However, the vaccine had no effect on the patients’ slide into dementia, despite the fact that autopsies of patients who died during the study showed that the plaques had largely vanished.
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In a sign of the slow progress in the medical fight against the HIV virus and AIDS, a federal health agency has canceled plans for an ambitious clinical trial of an experimental HIV vaccine. Although this candidate vaccine was once thought very promising, researchers lost confidence in it after the failure last September of a similar candidate from drugmaker Merck & Co. that may have left some volunteers more vulnerable to HIV infection [San Francisco Chronicle].
Researchers at the National Institute of Allergy and Infectious Diseases had hoped to begin enrolling 8,500 volunteers in the vaccine trial last fall, but the trial was postponed after the Merck vaccine was shown to be failing in its two main objectives: to prevent infection and to lower the amount of H.I.V. in the blood among those who became infected…. After a safety monitoring committee detected the problems with the Merck vaccine in September, the company quickly halted its study [The New York Times].
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