Local scientists may have found way to outsmart brain’s built-in defense

By Marshall Allen

Tuesday, July 28, 2009 | 2 a.m.

Brain cancer has been difficult to treat, in part, because the mind has an incredible defense system.

The “blood brain barrier” is made up of blood vessels with cell walls so tightly packed they filter out disease while allowing into the brain glucose and oxygen — fuels we need to survive.

The problem arises when a cancer tumor lies behind the firewall. Chemotherapy agents are unable to penetrate the defense, which makes it difficult to kill the cancer.

UNLV and Nevada Cancer Institute scientists published an article about a possible solution to the challenge in the June issue of the Journal of Neuro-Oncology.

Steen Madsen, associate professor and chair of health physics at UNLV, said scientists had discovered ways to disable the blood brain barrier, but they essentially took out the entire defense system at once. That allowed disease and fluids to flood the brain, causing sickness and dangerous swelling.

Madsen and the team had to find a way to open the blood brain barrier in selective areas so they could attack the cancer cells. They injected a small amount of a particular toxin into the targeted area of the brains of rats, combined with a drug that became active when it was hit with a laser light. When they zapped it with a laser light the blood brain barrier would open up in that region for about 10 days.

The discovery is many years away from clinical trials on humans, Madsen said.

UNLV is better known for its hospitality program and basketball team, Madsen said, but it is also focused on research.

The University of California, Irvine, was also a partner in the project. Nevada Cancer Institute provided a $50,000 grant for the project and performed the imaging necessary for the research.

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The truth is sometimes a casualty of battles between unions and employers.

The campaign by the California Nurses Association to win the hearts of nurses at MountainView Hospital has been no exception.

In a complaint to the National Labor Relations Board, the union accused the hospital of using religion to manipulate nurses. The union claims that hospital managers said the union was pro-choice when the union had never taken any stand on the abortion issue, union representatives told the Las Vegas Sun.

That’s not true.

The union opposed — with other medical associations — a 2005 California proposition that mandated a waiting period and parental notification before terminating a minor’s pregnancy, and a proposal in 2000 to ban partial-birth abortions.

Charles Idelson, the union’s communication director, became defensive when the Sun asked him about the union’s past stances on abortion. Idelson chastised the Sun for raising an irrelevant topic.

It’s relevant because the union brought it up as part of its federal labor complaint, and because Idelson and another union representative, when asked, said the union had never taken a position on abortion.

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Rats learned to “play the odds” in a gambling study published recently in the journal Neuropsychopharmacology.

Researchers from the University of British Columbia created a gambling task in which the rats had a limited time to maximize the number of food pellets by choosing one of four options, with varying amounts of sugar pellets and risk. Larger rewards were associated with a higher chance of longer timeouts, resulting in less overall reward in the time period.

The rats were able to consistently choose options that maximized their payoff, and researchers were able to use various drugs to impair or improve their performance, the study said.

The findings suggest that drugs can be used to address problem gambling in humans, and that the rat test will be a useful tool to study the biology of gambling, the study said.