WEDNESDAY, May 7 (HealthDay News) -- A new class of weight-loss drugs that suppresses appetite by blocking cannabinoid receptors in the brain should be used with caution in children, U.S. scientists report.

In research with mice, they found this class of drugs also suppresses the adaptive rewiring of the brain necessary for neural development in young animals. The findings are in the May 8 issue of Neuron.

One such drug is rimonabant (Acomplia), which was developed by Sanofi-Aventis and is awaiting approval by the U.S. Food and Drug Administration. Other pharmaceutical companies are developing similar drugs.

In this study, researchers concluded that a cannabinoid receptor-blocking drug called AM 251 affected experience-dependent cortical plasticity in the brains of juvenile mice. This plasticity is the experience-prompted adaptive rewiring of the brain that plays an critical role in the neural development of young animals.

"Our finding of a profound disruption of cortical plasticity in juvenile mice treated with AM 251 suggests caution is advised in the use of such compounds in children," wrote Mark F. Bear and his colleagues, of the Howard Hughes Medical Institute, The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, in Cambridge, Mass.

More information

The Nemours Foundation has more about childhood obesity  .

WEDNESDAY, May 7 (HealthDay News) -- For the first time, a gene linked to the often fatal childhood cancer neuroblastoma has been identified, researchers report.

"This is the first paper that helps us understand what causes this childhood cancer," said lead researcher Dr. John M. Maris, director of the Center for Childhood Cancer Research at The Children's Hospital of Philadelphia. "We expected for decades that this cancer was a genetic disease, but we have had a hard time understanding what abnormalities in our genetic makeup lead to this cancer."

Neuroblastoma, a cancer of the peripheral nervous system that usually appears as a solid tumor in the chest or abdomen, is the most common solid tumor malignancy seen in early childhood. Among infants, it can disappear with minimal treatment, but in older children, it can be an aggressive cancer spreading throughout the body. Neuroblastoma accounts for 7 percent of all childhood cancers but causes 15 percent of all childhood cancer deaths. There are about 700 new cases diagnosed each year in the United States, the researchers said.

Maris' team found a common genetic variation of the gene 6p22 on chromosome 6, which doubles the risk of getting this disease. "This finding supports our assumption that there are a number of minor variations that work together -- in sort of a perfect storm -- to give a child this disease," he said. "This finding is the discovery of the first of these genetic variants."

Maris noted that this is the first time a childhood cancer has been found to be influenced by rather common genetic changes "that can be in you or me or anyone."

In addition, Maris said that having this particular genetic variation not only increases the risk of developing neuroblastoma, but also increases the risk of developing the more aggressive form of the disease. "This leads us to believe that the disease we call high-risk or low-risk neuroblastoma are really different diseases," he said.

The findings were published in the May 7 online edition of the New England Journal of Medicine.

For the study, Maris' team analyzed blood samples from 1,032 children with neuroblastoma and 2,043 children without the disease. The researchers honed in on three single nucleotide polymorphisms (SNPs) -- which are variations in DNA -- that were more common in patients with neuroblastoma than in patients without the disease. The three SNPs were clustered in the 6p22 region of chromosome 6. There are two genes in this region, but exactly what they do is unknown, the researchers said.

To confirm their findings, Maris' group analyzed blood samples from additional neuroblastoma patients and children without the disease. Among these additional patients, the researchers also found that variants in the 6p22 region were associated with increased risk for neuroblastoma.

"This finding gives us the motivation to continue this line of research to discover all of the different genetic variations that work together," Maris said. "We have already discovered additional variations."

Knowing the complete genetic influences on neuroblastoma may eventually lead to new treatments, he said.

Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society, said that the new findings could one day lead to better diagnosis and treatment of the malignancy. "We still need to understand what these genes do, because little is known about these genes," he said.

Lichtenfeld added that, while the new research is important, it's still very preliminary. "Ultimately, what you want to do is to analyze the cancer and gain clues as to what the prognosis may be and what the appropriate treatment may be," he said. "This does not get us there, but it is one step along that pathway."

More information

For more on neuroblastoma, visit the American Cancer Society  .

MONDAY, May 5 (HealthDay News) -- A small proportion of adopted American teens appear to be at heightened risk for different emotional and behavioral problems than their non-adopted counterparts.

But that risk is moderate, emphasized the authors of a study in the May issue of Archives of Pediatrics & Adolescent Medicine.

"Most adoptees are doing fine," said Margaret Keyes, lead author of the study and research psychologist at the Minnesota Center for Twin and Family Research at the University of Minnesota in Minneapolis. Still, new data on the long-term health of adopted children is always useful, she reasoned.

"When you have all the information, you're better prepared to make decisions for your family," Keyes said. "You have information that your adopted child might be at a slightly increased risk, so you can be aware of that and can you use the social services agencies with which you already familiar through the process of adopting."

"There is no revelation here. This is consistent with previous research," added Adam Pertman, executive director of the Evan B. Donaldson Adoption Institute and author of Adoption Nation. "It's a good, solid piece of work. Adoptive parents can be reassured that their kids will be just fine, thank you. We do need to do a better job of learning how to deal with children and be prepared in case we are in that minority whose kids are represented in this study. It's not scary. It's cautionary."

According to background information in the article, some 120,000 children are adopted annually in the United States, and there are about 1.5 million adopted American children under the age of 18.

International adoptions are increasingly replacing domestic adoptions, with about 40,000 children transferred between more than 100 countries each year as a result of adoption.

Although some studies have found an increased risk of social, intellectual and emotional problems among children who were exposed to substances before they were born or who were neglected prior to adoption, the risk among children who don't have this kind of history hasn't been clear.

The researchers assessed 514 internationally adopted adolescents and 178 domestically adopted adolescents (aged 11 to 21) and compared them with 540 non-adopted kids of the same age.

Children who had been adopted scored higher than non-adoptees on continuous measures of behavioral and emotional problems, the team found. Adoptees were about twice as likely to have had contact with a mental health professional and of having a disruptive behavior disorder, according to the study.

Domestic adoptees were more than twice as likely to have an "externalizing disorder" (one that manifests in outward behavior) than international adoptees, the researchers added.

As one example, seven out of every 100 non-adopted kids met the criteria for ADHD (attention deficit hyperactivity disorder), while 14 to 15 of adopted kids met the criteria, Keyes said. Still, the overall rate was not alarming.

To put it into perspective, Keyes pointed out that simply giving birth to a male is risky, since boys have a higher chance of being diagnosed with a disruptive behavior disorder than girls.

"It's important not to stigmatize adoption," Pertman said. "Adoption is not causing these problems."

A second study in the same issue of the journal looked at children who had lost a parent to death suddenly. Researchers at the University of Pittsburgh School of Medicine found that these bereaved youngsters had triple the risk of depression and post-traumatic stress disorder (PTSD) than kids with two parents still alive.

According to the article, 4 percent of children in Western countries have experienced the death of a parent.

More information

There's more on adoption at the Evan B. Donaldson Adoption Institute  .

SATURDAY, May 3 (HealthDay News) -- Approximately one in 10 U.S. children uses one or more cough and cold medications during a given week, according to new research from Boston University.

While cough and cold medications for children are widely marketed in the United States, how frequently they are used had not been scientifically studied. This new finding, from researchers at Boston University's Slone Epidemiology Center, gives increased weight to recent revelations that cough and cold medication use can lead to serious adverse effects, including death.

"Given concerns about potential harmful effects and lack of evidence proving that these medications are effective in young children, the fact that 1-in-10 U.S. children is using one of these medications is striking," study author Dr. Louis Vernacchio, an assistant professor of epidemiology and pediatrics at Boston University School of Medicine, said in a prepared statement.

Yet, the researchers also reported positive news in children's use of cough syrup and other drugs. The overall use of cough and cold medications declined from 12.3 percent in 1999-2000 to 8.4 percent in 2005-2006, they found.

The findings were scheduled to be presented Saturday at the Pediatric Academic Societies meeting in Honolulu.

Researchers analyzed data gathered between 1999 and 2006 through a national telephone survey and considered all oral medicines approved by the U.S. Food and Drug Administration to treat children's coughs and colds.

In any given week, 10.1 percent of U.S. children took at least one cough and cold medication, the researchers found. In terms of active ingredients, most used were decongestants and antihistamines (6.3 percent each), followed by anti-cough medicines (4.1 percent) and expectorants (1.5 percent).

Children aged 2 to 5 used the medications most often, but the rate was also high among those younger than 2.

More information

The American Association of Pediatrics has more about cold remedies for children  .