Battle of the bugs blamed for bad breath

11:34 19 February 03

NewScientist.com news service

People who suffer from bad breath could lack a set of "good" bacteria that bind preferentially to their tongues and keep foul-smelling micro-organisms at bay. The new research suggests mouths could be kept fresh with the use of pro- rather than anti-bacterial mouthwash.

Bruce Paster and colleagues from the Forsyth Institute in Boston, Massachusetts used a gene-sequencing technique to identify the bacteria living on people's tongues.

They found that those suffering from halitosis tend to lack the three bacterial strains most common in sweet-smelling mouths and instead harbour a host of previously unknown bugs.

"This is the first application of the concept of good and bad bacteria to halitosis," says Jeffrey Hillman at the University of Florida. Hillman recently created a strain of genetically modified, "good" bacteria to help combat tooth decay by killing off acid-producing strains.

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Fresh secret of penguin dads revealed : Antibiotic produced in Stomach?

19:00 19 February 03

Exclusive from New Scientist Print Edition

Male king penguins store undigested food in their stomachs for up to three weeks. The talent is unique among higher vertebrates and ensures a constant supply of food for their chicks. But how they do it was a mystery.

Now an analysis of the birds' stomach contents shows the penguins keep food fresh by destroying bacteria in their stomachs, suggesting that they produce an antibacterial agent in their digestive tracts.

The penguins could be suppressing the bacteria with acrylic acid, an antibacterial compound from phytoplankton, which is in turn found in the stomachs of the penguins' prey. But the birds appear to be able to switch on the preservation process, suggesting that they actively release one or more bactericidal agents.

Journal reference: Polar Biology (vol 26, p 115)

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X-ray trick picks out tiny tumours

19:00 19 February 03

Exclusive from New Scientist Print Edition

An ingenious advance in mammography may make it possible to detect cancer at a much earlier stage. A research team has discovered that tumour cells give away their presence by scattering X-rays in a unique way, making them much easier to pinpoint among healthy cells.

In Britain, breast cancer affects one woman in 10, and is the biggest cause of cancer deaths among them. And like all cancers, early detection is crucial for reducing the chances of the tumour shedding cells and spawning secondary tumours elsewhere in the body.

But with today's cancer-screening systems, it is very hard to spot growths that are less than 10 millimetres wide, particularly in women younger than 45. That is because healthy breast tissue and tumours look very similar on a conventional mammogram. At that size, doctors are trying to find slightly less grey areas in fields of grey.

But physicist Robert Speller and a team at University College London are developing a new form of mammogram that can detect tumours only four millimetres wide, when they are too small to spawn secondaries and are easier to excise by surgery.

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Oil and water do mix after all

19:00 19 February 03

Exclusive from New Scientist Print Edition


Oil and water do not mix - the mantra is familiar to every schoolchild. You have to shake them to overcome the forces that hold the oil together.

Now teachers may want to rewrite their lessons. If you first remove any gas that is dissolved in the water, it will mix spontaneously and even stay that way indefinitely, according to chemist Ric Pashley of the Australian National University in Canberra.

"Many scientists are going to find this very hard to believe," says colloid scientist Len Fisher of the University of Bristol in England, "but Pashley has provided very strong proof that oil and water will mix." Pashley's observation is bound to cause controversy as the reason it happens is still unclear. Chemists are waiting to see whether the experiment can be repeated.

If spontaneous emulsions can be made at will, they could have important applications in medicine and the chemical industry. Many injectable medicines are currently only soluble in oil.

An alternative might be to disperse the medicine in degassed water, which is already produced on a large scale by the oil industry. Emulsion paints, which currently use chemical stabilisers to stop them separating, could also be made more cheaply if degassed water would do the trick.

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Two children of AIDS victms "fast" their way to school
- -Kollam: At an age when they should be frolicking around, two orphaned siblings have had to brave odds to get themselves admitted to a schoool -- Not for monetary reasons but because both their parents died of the dreaded Acquired Immuno Deficiency Syndrome, called AIDS.

Seven year old Bency and five year old Benson, who are also infected with HIV will attend school from Monday, after a government school in their Kollam district admitted them following the chief minister's intervention. The children were denied their basic right to education as school after school refused them admission as word about their HIV condition and parents' past spread faster than they took to reach the insitutions, said Lalan C Jacob, Project Officer of a National AIDS Control Organisation (NACO) aided NGO at Punaloor under the Kerala State AIDS Control.

On Friday, the children staged a day-long fast in front of State Secretariat at Thiruvananthapuram, hoping to move some hearts. The Chief Minister A K Antony moved and directed the concerned authorities to ensure that Bency and Benson were admitted to a school. According to an official release in Thiruvanthapuram, the children have been admitted to Kayathakuezhi at Chathamoor in Kollam district, where they hail from. While their father died in December 1997, their mother passed away in September 2000. The children are now with their old grandparents and would start going to school from Monday, Jacob said when contacted from Kochi.

Prostate cancer most common among U.S. men

WASHINGTON (Reuters) - Prostate cancer, recently diagnosed in both Massachusetts Sen. John Kerry and television evangelist Pat Robertson, is the single most common form of cancer in U.S. men.

It will affect an estimated 220,900 men this year, according to the American Cancer Society, and will kill nearly 29,000.

Lung cancer is much more deadly. It will affect 171,000 Americans in 2003, according to the ACS, and will kill 157,000, including 88,000 men. Breast cancer will affect an estimated 212,000 U.S. women and will kill 40,000.

An American man has a 16 percent chance of developing prostate cancer in his lifetime, but the disease has a relatively low mortality rate because it is a slow-growing cancer, easily cured if caught early.

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AIDS experts call for rethink of testing policy

LONDON (Reuters) - AIDS experts in the United States have called for a rethink of public HIV testing policy, saying new technology to diagnose the AIDS virus could streamline the procedure and reduce the spread of the disease.

In a letter to The Lancet medical journal on Friday, Mary Jane Rotheram-Borus of the UCLA AIDS Institute and Mark Etzel of the UCLA Center for Community Health in California said a flexible approach to counselling is needed because a new, rapid HIV test can produce a result within an hour.

Instead of counselling people before and after testing, counselling should only be given if the test is positive or if the person reports high-risk behaviour, they said.

"Local clinics are forced to spend their money on counselling staff instead of needed drugs and treatment. Freeing these resources will open up new services for HIV-infected persons," said Rotheram-Borus.

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