Natural killer (NK) cells are white blood cells which home in on infected or cancerous cells, releasing agents that induce apoptosis, or "cell suicide". NK cells are especially active against viruses.

The research emerged from findings that stress and depression impair NK cell function and can accelerate the progress of HIV/ Aids. Scientists recruited depressed and non-depressed HIV-positive women and treated them with three drugs to treat stress and depression. Two, Citalopram and the "substance P antagonist" CP-96345 increased NK cell activity, while RU486 had no effect.

A vast array of pharmaceuticals - including antibiotics, anti-convulsants, mood stabilizers and sex hormones - have been found in the drinking water supplies of at least 41 million Americans, an Associated Press investigation shows.

To be sure, the concentrations of these pharmaceuticals are tiny, measured in quantities of parts per billion or trillion, far below the levels of a medical dose. Also, utilities insist their water is safe.

But the presence of so many prescription drugs - and over-the-counter medicines like acetaminophen and ibuprofen - in so much of our drinking water is heightening worries among scientists of long-term consequences to human health.

People take pills. Their bodies absorb some of the medication, but the rest of it passes through and is flushed down the toilet. The wastewater is treated before it is discharged into reservoirs, rivers or lakes. Then, some of the water is cleansed again at drinking water treatment plants and piped to consumers. But most treatments do not remove all drug residue.

Even users of bottled water and home filtration systems don't necessarily avoid exposure. Bottlers, some of which simply repackage tap water, do not typically treat or test for pharmaceuticals, according to the industry's main trade group. The same goes for the makers of home filtration systems.

A nasal spray containing a naturally occurring brain hormone called orexin A reversed the effects of sleep deprivation in monkeys, allowing them to perform like well-rested monkeys on cognitive tests. The discovery's first application will probably be in treatment of the severe sleep disorder narcolepsy.

The treatment is "a totally new route for increasing arousal, and the new study shows it to be relatively benign," said Jerome Siegel, a professor of psychiatry at UCLA and a co-author of the paper. "It reduces sleepiness without causing edginess."

Orexin A is a promising candidate to become a "sleep replacement" drug. For decades, stimulants have been used to combat sleepiness, but they can be addictive and often have side effects, including raising blood pressure or causing mood swings. The military, for example, administers amphetamines to pilots flying long distances, and has funded research into new drugs like the stimulant modafinil (.pdf) and orexin A in an effort to help troops stay awake with the fewest side effects.

While the panel overwhelmingly said the products haven't been proven to work in children 11 and younger, the panel, by a vote of 15 to 7, stopped short of recommending the products not be used at all in older children.

Amy Celento-Stamateris, the patient representative on the panel, said if there were no children's cold and cough products on the market, "there are many people who will administer (adult) products to their children because they work for them and I'd be very concerned."

The advice has left many parents wondering what to do when their kids are suffering from stuffy noses, sniffles or hacking coughs.

"You've got to take it seriously. I want to be cautious," says Alison Schwartz, a 36-year-old mom who lives in Sacramento, Calif. "But on the other hand, it's really hard with a child - especially a kid under 6 - to watch him up all night coughing, with a cold or the flu, and not be able to give him something to give him a little relief, just so he can get some sleep."

Like many parents, Schwartz argues that the over-the-counter cold medicines have always seemed to work for her son, 3-year-old Owen.

The FDA meeting came just a week after several manufacturers pulled sales of nonprescription cold drugs targeted at children under 2. The move followed questions by the FDA and other health groups over a number of reported deaths linked to the remedies in recent years. The deaths occurred when parents gave their children accidental overdoses.

It's troubling news for many parents who now aren't sure how to best care for a child with a cold.

The oral antibiotics, representing the most commonly filled at the chain's pharmacies, will be available at no cost to anyone with a prescription as often as they need them, Publix CEO Charlie Jenkins Jr. said. Fourteen-day supplies of the seven drugs will be available at all 684 of the chain's pharmacies in five Southern states.

The prescription antibiotics available under the program are amoxicillin, cephalexin, penicillin VK, erythromycin, ampicillin, sulfamethoxazole/trimethoprim, and ciprofoxacin.

Gov. Charlie Crist went to a suburban Fort Myers store to help the company make the announcement and to praise the Lakeland-based employee-owned company, one of the dominant retailers in the region.

"It can't be any more affordable than free," Crist said.

As part of a pilot program, the Food and Drug Administration will issue drug “report cards” that would detail unexpected side effects that emerge only after a drug has been approved. The reports also would include follow-up studies and details about how the drugs are being used.

The proposal is one of roughly a dozen initiatives, new and ongoing, that the FDA unveiled Tuesday in response to a recent report by a committee of experts at the Institute of Medicine that criticized the agency's handling of drug safety in the wake of the Vioxx case.

It comes just days before Sens. Edward Kennedy, D-Mass., and Mike Enzi, R-Wyo., introduce legislation to overhaul how the FDA handles drug safety.

"Today's report is thoughtful and provides important recommendations for administrative action, but only legislation can give FDA the tools it needs to ensure that FDA is the gold standard for safety," Kennedy said in a statement.

Early tests of skin-patch vaccines are beginning in hundreds of volunteers, one version designed to protect against the flu and another to prevent travelers' diarrhea.

The idea isn't just pain-free vaccination. The National Institutes of Health is helping fund patch research in hopes of strengthening today's imperfect flu shots, and gaining extra help if bird flu or some other super-flu ever triggers a pandemic.

Indeed, patch developer Iomai Corp. proposes that the mailman, not a doctor, deliver flu vaccine during a pandemic. Once a vaccine is brewed, simply ship patches to people's homes with instructions to slap one on.

Doctors might not like the go-it-alone method. But the technology's main promise may be in developing countries. Unlike syringe-based vaccines, patches wouldn't need refrigeration — nor pose the infection risk of reused needles, a continuing problem.

Report authors David Henry and Ray Moynihan criticised attempts to convince the public in the US that 43% of women live with sexual dysfunction.

They also said that risk factors like high cholesterol and osteoporosis were being presented as diseases -- and rare conditions such as restless leg condition and mild problems of irritable bowel syndrome were exaggerated.

The report said: "Disease-mongering is the selling of sickness that widens the boundaries of illness and grows the markets for those who sell and deliver treatments."

They suggest adults should use older non-prescription antihistamines and decongestants to stop the flow of mucus that causes the cough.

Children can be harmed by cough medicines, they warn, and they will usually get better without help.

It is possible children could be over-sedated with the medication, they said.

A productive cough produces phlegm or mucus (sputum). The mucus may have drained down the back of the throat from the nose or sinuses (postnasal drainage) or may have come up from the lungs. A productive cough generally should not be suppressed; it clears mucus from the lungs.

A nonproductive cough is dry and does not produce sputum. A dry, hacking cough may develop toward the end of a cold or after exposure to an irritant, such as dust or smoke.

Initial studies of the crocodile immune system in 1998 found that several proteins (antibodies) in the reptile's blood killed bacteria that were resistant to penicillin, such as Staphylococcus aureus or golden staph, Australian scientist Adam Britton told Reuters on Tuesday. It was also a more powerful killer of the HIV virus than the human immune system.

"If you take a test tube of HIV and add crocodile serum it will have a greater effect than human serum. It can kill a much greater number of HIV viral organisms," Britton said from Darwin's Crocodylus Park, a tourism park and research center.

Ritalin, now prescribed to children with attention deficit hyperactivity disorder (ADHD), has already been used by some students to improve their performance in exams.

Modafinil, used now to treat sleep disorders, has been shown to help people remember numbers more effectively.

It can also make people think more carefully before making decisions.

There is also a type of molecule called ampakins, which enhance the way some chemical receptors in the brain work, suggesting drugs could be developed to improve people's memory when they are tired.

The ATM-like machines are raising questions among pharmacists and state regulators who oversee prescription-drug dispensing. One worry is that patients might end up with the wrong drug. Some pharmacists also don't like the machines because they cut out traditional face-to-face consultations with patients. The concern is that patients might be discouraged from asking pharmacists about such things as whether alcohol should be avoided with a medicine, or possible drug interactions.

"There's lots of leeriness on the part of regulators and the fear that something like this could replace the pharmacist," says Mary Ann Wagner, vice president of pharmacy regulatory affairs for the National Association of Chain Drug Stores, a trade group in Alexandria, Va.

Most surprising, he said, was the widespread belief that the medical industry is hiding a cure. "It's just the reverse," DuBois said, noting that companies are trying to fast-track new drugs and treatments to get them to people as soon as possible.

The survey results, said DuBois, probably mean that cancer centers should "beef up their public education efforts." He noted, "There are more misconceptions out there than some people realize."