Monday, August 31, 2009
MONDAY, Aug. 31 (HealthCare tips), Scientists have isolated a group of hereditary mutations involved in the growth of melanoma, the deadliest form of skin cancer. Their work may lead to therapy with existing drugs that aim the same mutations.
Led by Yardena Samuels of the National Human Genome Research Institute, the research team from the U.S. National Institutes of Health (NIH) sequenced the protein tyrosine kinase (PTK) gene family in tumor and blood example from people with metastatic melanoma. Their study is published in the September issue of the journal Nature Genetics.
"We have found what appears to be an Achilles' heel of a sizable share of melanomas," Samuels, an examiner in the cancer genetics branch of the institute's Division of Intramural Research, said in a NIH news release.
The PTK family includes many genes that, when mutated, promote many types of cancer, including brain, gastric and lung malignancies, according to background information provided in the news release. In the new NIH study, one PTK gene that appeared mainly suspicious was the ERBB4 gene. Scientists found ERBB4 changes in 19 percent of patients' tumors, making it the most frequently mutated PTK gene in melanoma. Additional lab studies found that melanoma cells with the ERBB4 imperfection were dependent on the mutant gene for their growth.
The researchers also found that two extra PTK genes , FLT1 and PTK2B , were mutated in about 10 percent of the tumor samples.
The discoveries could open up new avenues for therapies. For example, the researchers exposed that melanoma cells grew much more slowly when exposed to lapatinib (Tykerb), a chemotherapy drug that inhibits ERBB4. Lapatinib is already in use by some breast cancer patients. The NIH team is preparing a clinical trial using lapatinib in patients with metastatic melanoma harboring ERBB4 mutations.
"Though additional work is needed to gain a more complete understanding of these genetic mutations and their roles in cancer biology, our findings open the door to pursuing specific therapy that may prove useful for the treatment of melanoma with ERBB4 mutations," Samuels stated.
Led by Yardena Samuels of the National Human Genome Research Institute, the research team from the U.S. National Institutes of Health (NIH) sequenced the protein tyrosine kinase (PTK) gene family in tumor and blood example from people with metastatic melanoma. Their study is published in the September issue of the journal Nature Genetics.
"We have found what appears to be an Achilles' heel of a sizable share of melanomas," Samuels, an examiner in the cancer genetics branch of the institute's Division of Intramural Research, said in a NIH news release.
The PTK family includes many genes that, when mutated, promote many types of cancer, including brain, gastric and lung malignancies, according to background information provided in the news release. In the new NIH study, one PTK gene that appeared mainly suspicious was the ERBB4 gene. Scientists found ERBB4 changes in 19 percent of patients' tumors, making it the most frequently mutated PTK gene in melanoma. Additional lab studies found that melanoma cells with the ERBB4 imperfection were dependent on the mutant gene for their growth.
The researchers also found that two extra PTK genes , FLT1 and PTK2B , were mutated in about 10 percent of the tumor samples.
The discoveries could open up new avenues for therapies. For example, the researchers exposed that melanoma cells grew much more slowly when exposed to lapatinib (Tykerb), a chemotherapy drug that inhibits ERBB4. Lapatinib is already in use by some breast cancer patients. The NIH team is preparing a clinical trial using lapatinib in patients with metastatic melanoma harboring ERBB4 mutations.
"Though additional work is needed to gain a more complete understanding of these genetic mutations and their roles in cancer biology, our findings open the door to pursuing specific therapy that may prove useful for the treatment of melanoma with ERBB4 mutations," Samuels stated.
Labels: Skin cancer
Thursday, August 27, 2009
THURSDAY, Aug. 27 (Health care tips) , kids who are allergic to milk may be able to overcome their allergy by drinking increasingly higher doses of milk, a new study finds.
In 2008, researchers from Johns Hopkins Children's Center in Baltimore statement that children with a severe milk allergy could "retrain" their immune systems to tolerate milk and other dairy products by slowly consuming increasingly higher doses.
In the current study, researchers followed up with 18 children aged 6 to 16 whose indications had eased or gone away during the previous study.
When 13 of the 18 children returned to the clinic up to 17 months later, six continued to have no response after drinking 16 ounces of milk, twice the highest quantity tested in the earlier study. Seven children had gentle reactions, including itchy mouth, hives, sneezing and stomachache after drinking less than 16 ounces. One child needed medicine for a cough, the researchers noted in a news release from Johns Hopkins.
The researchers also followed up with three children who could not drink more than 2.5 ounces at the end of the preceding
study. All three continued to drink milk daily with only mild reactions, and two were able to drink more than 2.5 ounces with few problems, the study writers found.
The study was published in the Aug. 10 online subject of the Journal of Allergy and Clinical Immunology.
One key to keeping the allergy at bay seems to be regular use of milk and dairy products, according to the study.
"We now have proof from other studies that some children once successfully treated remain allergy-free even without daily exposure, while in others the allergies return once they stop usual daily exposure to milk," said senior author Dr. Robert Wood, director of Allergy & Immunology at Johns Hopkins Children's Center. "This may indicate that some patients are truly cured of their allergy, while in others the immune system adapts to regular daily exposure to milk and may, in fact, need the exposure to continue to bear it."
The researchers also experienced for milk allergy using skin-prick testing, a standard food allergy test. Between eight and 15 months post-study, seven children had no reactions. Blood levels of milk IgE antibodies, which point out allergy, slowly decreased, while IgG4, an antibody that indicates immunity to an allergen, rose.
The study authors also found that the occurrence of reactions continued to decline over time.
As part of the study, children and their parents kept daily logs of milk and dairy consumption and recorded symptoms, such as hives, abdominal pain, sneezing and cough. For the first three months, drinking milk trigger reactions nearly half of the time. During the next three months, milk triggered reactions 23 percent of the time, while some children reported no reactions.
Milk allergy is the most familiar food allergy. In those who are allergic, milk proteins cause the immune system to overreact, bringing a cascade of symptoms that can range from hives, itching, swelling and vomiting to anaphylaxis in the most harsh cases.
Three million U.S. children have at least one food allergic reaction, according to the U.S. Centers for Disease Control and Prevention.
In 2008, researchers from Johns Hopkins Children's Center in Baltimore statement that children with a severe milk allergy could "retrain" their immune systems to tolerate milk and other dairy products by slowly consuming increasingly higher doses.
In the current study, researchers followed up with 18 children aged 6 to 16 whose indications had eased or gone away during the previous study.
When 13 of the 18 children returned to the clinic up to 17 months later, six continued to have no response after drinking 16 ounces of milk, twice the highest quantity tested in the earlier study. Seven children had gentle reactions, including itchy mouth, hives, sneezing and stomachache after drinking less than 16 ounces. One child needed medicine for a cough, the researchers noted in a news release from Johns Hopkins.
The researchers also followed up with three children who could not drink more than 2.5 ounces at the end of the preceding
study. All three continued to drink milk daily with only mild reactions, and two were able to drink more than 2.5 ounces with few problems, the study writers found.The study was published in the Aug. 10 online subject of the Journal of Allergy and Clinical Immunology.
One key to keeping the allergy at bay seems to be regular use of milk and dairy products, according to the study.
"We now have proof from other studies that some children once successfully treated remain allergy-free even without daily exposure, while in others the allergies return once they stop usual daily exposure to milk," said senior author Dr. Robert Wood, director of Allergy & Immunology at Johns Hopkins Children's Center. "This may indicate that some patients are truly cured of their allergy, while in others the immune system adapts to regular daily exposure to milk and may, in fact, need the exposure to continue to bear it."
The researchers also experienced for milk allergy using skin-prick testing, a standard food allergy test. Between eight and 15 months post-study, seven children had no reactions. Blood levels of milk IgE antibodies, which point out allergy, slowly decreased, while IgG4, an antibody that indicates immunity to an allergen, rose.
The study authors also found that the occurrence of reactions continued to decline over time.
As part of the study, children and their parents kept daily logs of milk and dairy consumption and recorded symptoms, such as hives, abdominal pain, sneezing and cough. For the first three months, drinking milk trigger reactions nearly half of the time. During the next three months, milk triggered reactions 23 percent of the time, while some children reported no reactions.
Milk allergy is the most familiar food allergy. In those who are allergic, milk proteins cause the immune system to overreact, bringing a cascade of symptoms that can range from hives, itching, swelling and vomiting to anaphylaxis in the most harsh cases.
Three million U.S. children have at least one food allergic reaction, according to the U.S. Centers for Disease Control and Prevention.
Labels: Health care tips, Milk allergic reactions
Monday, August 24, 2009
MONDAY, Aug. 24 .... As more and more instructions is being written for medications to treat attention-deficit hyperactivity confusion (ADHD), more and more children are abusing these medicines.
That's the end of new research in the September issue of Pediatrics that found the rate of ADHD medication abuse was up 76 percent from 1998 to 2005, and at the same time, the rates of prescriptions for these medicines rose about 80 percent.
"We looked at all the poisonous control centers across the nation and found a major increase in the number of calls for ADHD medication abuse that parallels the amount of prescriptions being written," said Dr. Jennifer Setlik, an emergency physician at Cincinnati Children's Hospital Medical Center in Ohio and a study author.
What's more, Setlik said, is that this study is "not an estimation of the total problem" because it looks only at data from toxic control centers, but it gives doctors and parents a snapshot of the trend toward rising mistreatment of these medications with increasing availability.
ADHD affects between 8 percent and 12 percent of kids, and as many as 4 pe
rcent of adultsworldwide, according to background information in the study. The disorder is commonly treated with refreshment medications, which have a seemingly paradoxical effect on people with ADHD, allowing them to focus and function more effectively. The drugs most often arranged are mixed amphetamine salts (Adderall) and methylphenidate (Ritalin, Concerta), according to the study.
The study also reports that next to marijuana, prescription medications are the most frequent drugs that teenagers use to get high. This may be because teens believe these medications are safe because they've been prescribed by a doctor, or simply because of their accessibility.
To assess whether increased availability of ADHD medications would also cause a rise in the number of teens abusing the drugs, Setlik and her colleagues review data from the National Poison Data System, which includes information from poison control centers across the United States.
The researchers looked for cases of deliberate abuse or misuse of ADHD medications in youths 13 to 19 years old from 1998 through 2005.
They found that over the eight-year study period, the number of calls to poison control centers concerning ADHD medication use went up 76 percent, from 330 calls during the first year to 581 calls the last year.
At the same time, overall ADHD prescriptions improved by 80 percent for all children and teens, and about 86 percent for kids between 10 and 19 years old.
The data didn't include information about whether a teen abusing an ADHD medication was the one who had been agreed the drug or whether the abuser was a teen without ADHD who was taking the medications.
Parents "need to be aware of the possible for the abuse of these medications for teens that have and haven't been prescribed them," Setlik said.
If a child is taking ADHD medication, she suggested keeping an eye on the amount the child is using.
Tom Hedrick, one of the beginning members of The Partnership for a Drug-Free America, agreed that parents need to monitor any prescription medications their children use to make sure that they're being used properly. He also advised parents to maintain their own prescriptions.
But what's critical, he said, is letting your kids know that taking drugs that weren't arranged for them, or taking more than what was prescribed is not OK.
"We have to start thinking proactively instead of reactively," said Hedrick. "Fifty percent of kids report never hearing a single word about prescription drug abuse, but these drugs are just as dangerous, just as addictive and just as deadly as illegal drugs."
"Right now, parents may feel a sense of release that their kids are taking medicines and not street drugs," he said. "But what we really have is the perfect storm because there's a lack of consciousness and an ease of availability."
