Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:

Obama Touts Health Care Exchanges

A targeted, localized strategy to convince young people to enroll in the new health care exchanges was highlighted by President Barack Obama on Friday during a visit to California.

"Competition and choice are pushing down costs in the individual market, just like the law is designed to do," Obama said at a stop in San Jose, USA Todayreported.

The exchanges are online marketplaces where people can buy health insurance. Enrollment lasts from Oct. 1 2013 through March 2014. Coverage through the exchanges begins in January 2014.

California, Texas and Florida are the focus of Department of Health and Human Service efforts to encourage people -- especially young adults -- to sign up when enrollment in the health exchanges begins. About one-third of expected enrollees live in those three states, USA Todayreported.

About 6 million people in California are eligible, and 2.6 million are entitled to receive help paying for their plans. In that state, the federal government is promoting the health exchanges through partnerships with Spanish-language media and The California Endowment, and by providing grants to Community Health Centers.

"Quality, affordable care is not some earned privilege. It's a right," Obama said in his San Jose remarks. He made a similar pitch last month in Texas, USA Todayreported.

The government is looking to enroll a total of 30 million people in the exchanges, but is aiming for 7 million in the first year.

In an op-ed article in the San Jose Mercury Newspublished to coincide with Obama's visit, Republicans said the new health care plan will wind up hurting most Americans by increasing their health costs, USA Todayreported.


New, More Accurate Test for Down Syndrome

A new test is more accurate than current methods of determining whether a fetus has Down syndrome, according to U.K. researchers.

Their study of 1,000 pregnancies showed that the test of fetal DNA in a mother's blood reveals if there is either a more than 99 percent chance, or a less than one in 10,000 likelihood, that a baby has Down syndrome, BBC Newsreported.

The test can also be given earlier in pregnancy than other tests and could help women decide if they require further, invasive tests, the King's College London team said.

The research appears in the journal Ultrasound in Obstetrics and Gynecology.


Judge Suspends Age Rule for Another Child Needing Lung Transplant

The judge who ordered that a dying 10-year-old girl be placed on the adult waiting list for a lung transplant has made a similar ruling for an 11-year-old boy.

On Wednesday, U.S. District Judge Michael Baylson ordered that a 12-and-over age requirement be suspended for Sarah Murnaghan, who has end-stage cystic fibrosis. He then made a similar ruling Thursday for Javier Acosta, who also has cystic fibrosis, the Associated Pressreported.

Acosta's mother filed a lawsuit Thursday after Baylson made his ruling in Murnaghan's case. An expert questioned the court rulings, which apply only to these two children, on medical and ethical grounds.

"When a judge steps in and says, 'I don't like these rules, I think they're arbitrary,' they better be very arbitrary or he's undermining the authority of the whole system," Dr. Arthur Caplan, a bioethicist at New York University Langone Medical Center, told the AP.


New Rules Would Require Labeling of Mechanically Tenderized Beef

Labels on beef would have to disclose whether the meat was mechanically tenderized, under proposed new rules announced Thursday by the U.S. Department of Agriculture.

About a quarter of the beef sold in the U.S. is mechanically tenderized, an unlabelled process which uses needles or blades and regulators say contributes to contamination with E. coli and other pathogens, Bloomberg Newsreported.

Consumer groups have campaigned for labeling of mechanically tenderized meat, pointing to studies that show the needles can push E. coli from the surface deep inside the meat where it is harder to kill through cooking. Mechanically tenderized beef looks no different than non-tenderized beef.

The labels disclosing the use of mechanical tenderizing will also have to include cooking instructions to help protect consumers. The new rules could take effect as soon as next year, Bloombergreported.