Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
Scientists Use Urine to Create New 'Teeth'
Scientists who grew tooth-like structures in mice using cells collected from human urine say their research could lead to a new way of replacing teeth lost due to age or poor dental hygiene.
The Chinese team gathered cells -- such as those that line the urinary tract -- found in urine and coaxed the cells into becoming stem cells, which are cells that can grow into any type of tissue. A mixture of the cells and other material were implanted in mice, BBC News reported.
Within three weeks, there were tooth-like structures. However, they were not as hard as natural teeth, according to the study in Cell Regeneration Journal.
This research won't immediately lead to the regeneration of teeth for patients, but could be a step in that direction, said the scientists at the Guangzhou Institutes of Biomedicine and Health.
One expert wasn't impressed with the study, saying that urine was a poor starting point for creating new teeth.
"It is probably one of the worst sources, there are very few cells in the first place and the efficiency of turning them into stem cells is very low," Professor Chris Mason, a stem cell scientist at University College London in the U.K., told BBC News. "You just wouldn't do it in this way."
NYC Ban on Large Sodas Struck Down by Appeals Court
New York City's ban on large sodas has been struck down by an appeals court.
In a unanimous decision, the four-judge panel of the state Supreme Court Appellate Division said that the city's Board of Health exceeded its legal authority and acted unconstitutionally when it moved to limit the size of sodas and other sugary beverages served in restaurants and other food outlets, CBS News/Associated Press reported.
While the health board has the power to ban "inherently harmful" food and beverage products from being served to the public, sugary drinks don't fall into that category, the judges said.
The city plans a quick appeal.
"Today's decision is a temporary setback, and we plan to appeal this decision as we continue the fight against the obesity epidemic," Mayor Michael Bloomberg said in a statement, CBS News/AP reported.
Arkansas Girl Infected With Deadly Brain Parasite
A 12-year-old Arkansas girl infected with a rare but deadly brain-eating parasite is in critical condition eight days after being admitted to Arkansas Children's Hospital.
Kali Hardig's infection was caused by an amoeba called Naegleria fowleri, which enters the body through the nose and travels to the brain. The infection typically occurs in people who have been swimming in warm freshwater, CNN reported.
"This infection is one of the most severe infections that we know of. Ninety-nine percent of people who get it die," Dr. Dirk Haselow, of the Arkansas Department of Health, told CNN affiliate WMCTC.
The most likely source of Hardig's infection is Willow Springs Water Park in Little Rock, according to the department of health. Another case involving the same parasite reported in 2010 was also linked to Willow Springs, CNN reported.
"Based on the occurrence of two cases of this rare infection in association with the same body of water and the unique features of the park, the ADH has asked the owner of Willow Springs to voluntarily close the water park to ensure the health and safety of the public," a department of health news release said.
Cases of N. fowleri infection are extremely rare, CNN reported. Between 2001 and 2010, there were 32 reported cases in the U.S., according to the Centers for Disease Control and Prevention. Most of the cases occurred in the Southeast.
Malaria Drug Gets Stronger Warning Label
Strengthened and updated warnings about the serious psychiatric and neurologic side effects that can be caused by the malaria drug mefloquine hydrochloride have been added to the drug's label, the U.S. Food and Drug Administration says.
The neurologic side effects can include dizziness, loss of balance or ringing in the ears. Psychiatric side effects can include feeling anxious, mistrustful, depressed or having hallucinations.
The neurologic side effects can occur at any time while taking the drug and can last for months to years after patients have stopped taking the drug, or can even be permanent, the FDA said.
The drug now carries a boxed warning, the most serious kind of caution. In addition, the medication guide and wallet card for the drug have been updated to include the new information.
Mefloquine hydrochloride is prescribed for mild to moderate acute malaria transmitted by certain types of mosquitoes and for the prevention of malaria infections caused by those mosquitoes. The drug was previously marketed under the brand name Lariam, but it is no longer marketed in the United States. However generic versions are available in the U.S.
Patients, caregivers and health care providers should watch for these side effects, the FDA said. If a patient develops neurologic or psychiatric symptoms, treatment with mefloquine hydrochloride should be stopped and another medicine should be used. Patients should not stop using the drug before consulting with a health care provider.