THURSDAY, Feb. 7 (HealthDay News) -- Tattooing is a more effective method for delivering DNA vaccines than intramuscular injection, a new German study finds.

Publishing in the online journal Genetic Vaccines and Therapy, researchers at the German Cancer Research Center in Heidelberg used a coat protein from the human papillomavirus (HPV), which causes cervical cancer, as a model DNA vaccine antigen. DNA vaccines are created using a modified form of an infectious organism's DNA.

In tests on mice, the researchers compared tattooing and intramuscular injection, with and without the adjuvants that are often given to boost immune response.

The tattoo method produced stronger antibody and cellular response than intramuscular injection, even when adjuvants were included in the injections. Three doses of DNA vaccine given by tattoo produced at least 16 times higher antibody levels than three intramuscular injections with adjuvant, the study found.

While adjuvants boosted the effect of intramuscular injection, it did not enhance the effect of tattooing.

The researchers explained that tattooing, which is done with a solid vibrating needle, causes a wound and sufficient inflammation to "prime" the immune system. It also covers a larger area of the skin than an injection, which means the DNA vaccine can enter more cells. This may be why tattooing produces a stronger immune response.

Because tattooing is painful, it may not be suitable for everyone. But it could prove useful in a number of areas, including cattle vaccination or therapeutic (rather than preventive) vaccination of humans, the researchers said.

"Vaccination with naked DNA has been hampered by its low efficiency. Delivery of DNA via tattooing could be a way for a more widespread commercial application of DNA vaccines," researcher Martin Muller said in a prepared statement.

More information

The U.S. National Institute of Allergy and Infectious Diseases has more about vaccines.

MONDAY, Feb. 4 (HealthDay News) -- Yet another study has found no evidence of a link between the measles, mumps and rubella (MMR) vaccine and autism.

The British authors of this latest research said theirs was the third and largest study that has looked for a connection between the MMR vaccine and autism, and has failed to find one.

"I think it's fabulous that they have scientifically, God willing, put this issue to rest, although parents will not agree with it and those people who are proponents of measles as the cause [of autism] will find a problem with the paper," said Dr. Pauline A. Filipek, an associate professor of pediatrics and neurology at the University of California, Irvine.

The British researchers based their finding on a sample of 240 children -- 98 who had been diagnosed with autism, and two comparison groups: 52 children with special educational needs who were not autistic; and 90 children who had no developmental problems.

All the children had received the MMR vaccine, but not all had had both doses. The researchers checked blood samples from all the children to look for the presence of persistent measles infection or an abnormal immune response. An abnormal response would have been indicated by circulating measles virus or increased antibody levels.

The researchers found the blood analysis showed no difference in circulating measles virus or antibody levels among the children. The finding was the same whether the children had one or two doses of the MMR vaccine.

In addition, autistic children and those with special educational needs were less likely to have had the second dose of the MMR vaccine, which may mean that parents were concerned about their children receiving the second dose because of their developmental problems.

The findings are reported in the February issue of the Archives of Disease in Childhood.

The controversy about the potential connection between autism and the MMR vaccine began in 1998 when British researcher Dr. Andrew Wakefield published a study in The Lancet that claimed the vaccine caused brain damage, resulting in autism.

Since that time, numerous studies have failed to confirm Wakefield's hypothesis.

"This study refutes the data Wakefield presented 10 years ago," Filipek said.

Filipek thinks parents hold onto the MMR vaccine-autism theory because "it gives them something to grasp onto that could be altered to prevent future cases of autism."

Dr. Paul A. Offit, director of the Vaccine Education Center and chief of infectious diseases at Children's Hospital of Philadelphia, also thinks the new study provides more conclusive evidence that there is no connection between autism and the MMR vaccine.

"The whole premise by Wakefield, that the measles component of [the] MMR vaccine caused a chronic intestinal inflammation that allowed harmful proteins to enter the bloodstream and ultimately the brain, causing autism, has not one shred of scientific evidence in its support," Offit said.

This new study follows the release last week of a study that showed the mercury preservative thimerosal, used in childhood vaccines until the turn of this century and thought by some to be associated with autism, doesn't remain in an infant's body long enough to build to dangerous levels.

And it follows a series of other studies, including a large-scale U.S. Institute of Medicine review in 2004, that failed to uncover a link between childhood vaccines and autism.

Current estimates by the U.S. National Institutes of Health say that one American child in 150 has been diagnosed with autism, although experts wonder if that increase is due in part to better diagnoses and a broader definition of the disorder.

More information

For more on autism, visit the U.S. National Institutes of Health.

TUESDAY, Feb. 5 (HealthDay News) -- Smokers are four times more likely to feel tired when they wake up and they spend less time in deep sleep than nonsmokers do, a new study finds.

This may be because smokers experience nicotine withdrawal each night, which may contribute to sleep disturbances, suggest the study authors, whose report appears in the February issue of Chest.

"It is possible that smoking has time-dependent effects across the sleep period. Smokers commonly experience difficulty falling asleep due to the stimulating effects of nicotine. As night evolves, withdrawal from nicotine may further contribute to sleep disturbance," study author Dr. Naresh M. Punjabi, of Johns Hopkins University School of Medicine in Baltimore, said in a prepared statement.

Punjabi and colleagues studied the sleep patterns of 40 smokers and 40 nonsmokers. They found that 22.5 percent of smokers reported a lack of restful sleep, compared with only 5 percent of nonsmokers. Smokers also experienced a lower percentage of deep sleep and a higher percentage of light sleep.

The largest differences in sleep between the two groups occurred at the onset of sleep, which suggests the effects of nicotine are strongest in the early stages of sleep and decrease as the sleep cycle progresses, the researchers said.

These findings may help develop more effective ways to help people stop smoking.

"Many smokers have difficulty with smoking cessation partly because of the sleep disturbances as a result of nicotine withdrawal," Punjabi said. "By understanding the temporal effects of nicotine on sleep, we may be able to better tailor nicotine replacement to minimize the withdrawal effects that smokers experience, particularly during sleep."

More information

The American Academy of Family Physicians explains insomnia  .

MONDAY, Feb. 4 (HealthDay News) -- While a spoonful of sugar helps the medicine go down, a new study shows it may also ease the pain of vaccinations.

And experts are hoping that a simple sugar-and-water solution will also ease parents' fears and boost immunization rates for infants.

"We're hoping this will encourage parents to get their children vaccinated," said study author Linda Hatfield, an assistant professor of public health services at the Pennsylvania State University School of Nursing in University Park. "It's very simple, not very expensive, babies leave the clinic just as they came in."

The strategy becomes one in an armamentarium of safer pain relievers for children.

"What's shaking out is a combination of things that can be used safely in pediatricians' offices that are useful to the child," said Dr. Kenneth R. Goldschneider, director of the division of pain management at Cincinnati Children's Hospital Medical Center in Ohio. "Sucrose, swaddling, kangaroo care [direct, skin-to-skin contact with a parent], non-nutritive sucking [a pacifier with nothing on it], topical analgesics, use of thinner needles and proper injection site selection [are all] means to keep painful interventions from being overly stressful. None of them are perfect, but they are safe, and work at least reasonably well."

According to Hatfield, this paper is one of the first to study infants who have already left the hospital; most previous studies were done on preterm newborns who, by circumstance, receive more shots. Her study is in the February issue of Pediatrics.

The annual immunization schedule for healthy new arrivals in this world is daunting; infants and toddlers receive as many as 24 injections in the first two years of life. As many as five injections can be given in a single visit.

But many parents are petrified at the prospect of seeing their child in pain.

"Some mothers say they've never heard their baby cry like that," Hatfield said. "They're reluctant to bring their sweet little children in."

There's also some indication that exposure to pain early in life might have long-term neurological effects.

American and Canadian pediatric groups already recommend the use of sucrose for minor painful procedures in neonates.

Hatfield and her colleagues randomized 100 2- and 4-month-old infants to receive either oral sucrose or a placebo (sterile water) 2 minutes before routine immunizations.

Pain was assessed with a score which took into account crying, facial expression, body movement, behavioral indications and sleep.

The sucrose group showed lower pain scores at 5, 7 and 9 minutes after being given the solution and, by 9 minutes, had a mean pain score 78.5 percent lower than that of the placebo group.

Parents were asked not to swaddle or cuddle their child during the immunization as this could have had an effect on the experience of pain.

Is it a good idea to give sugar to young babies? Hatfield says the solution is so weak (only one-quarter sugar) that it's unlikely to have any effect on later weight problems and doesn't even raise blood sugar in the short-term.

As for how sugar works, Goldschneider pointed to previous research proposing a link between exposure to sucrose and release of the body's natural pain-relieving chemicals.

More information

See the childhood immunization schedule at the U.S. Centers for Disease Control and Prevention.