国产诱惑福利

鈥淥ur goal is to give patients a head start,鈥� by boosting some new Alzheimer鈥檚 treatments that take a long time to work, said Dr. Ali Rezai of West Virginia University鈥檚 Rockefeller Neuroscience Institute, who led the study.

At issue is what鈥檚 called the blood-brain barrier, a protective lining in blood vessels that prevents germs and other damaging substances from leaching into brain from the bloodstream. But it also can block , tumors and other neurologic diseases, requiring higher doses for longer periods for enough to reach their target inside the brain.

Now scientists are using a technology called focused ultrasound to jiggle temporary openings in that shield. They inject microscopic bubbles into the bloodstream. Next, they beam sound waves through a helmetlike device to a precise brain area. The pulses of energy vibrate the microbubbles, which loosen gaps in the barrier enough for medications to slip in.

Prior small studies have found the technology can safely poke tiny holes that seal up in 48 hours. Now Rezai鈥檚 team has gone a step further 鈥� administering an Alzheimer鈥檚 drug at the same time.

Some new Alzheimer鈥檚 drugs, on the market or in the pipeline, promise to modestly slow worsening of the mind-robbing disease. They're designed to clear away a sticky protein called beta-amyloid that builds up in certain brain regions. But they require IV infusions every few weeks for at least 18 months.

鈥淲hy not try to clear the plaques within a few months?鈥� Rezai said, his rationale for the proof-of-concept study.

His team gave three patients with mild Alzheimer's monthly doses of one such drug, Aduhelm, for six months. Right after each IV, researchers aimed the focused ultrasound on a specific amyloid-clogged part of each patient鈥檚 brain, opening the blood brain-barrier so more of that day鈥檚 dose might enter that spot.

PET scans show patients鈥� amyloid levels before and after the six months of medication. There was about 32% greater plaque reduction in spots where the blood-brain barrier was breached compared to the same region on the brain鈥檚 opposite side, researchers reported in the New England Journal of Medicine.

This pilot study is elegant but too tiny to draw any conclusions, cautioned Dr. Eliezer Masliah of the National Institute on Aging.

Still, "it's very exciting, compelling data,鈥� added Masliah, who wasn鈥檛 involved with the research. 鈥淚t opens the door for more extensive, larger studies definitely.鈥�

Rezai is about to begin another small test of a similar but better proven drug named . Eventually large studies would be needed to tell if combining focused ultrasound with Alzheimer鈥檚 drugs makes a real difference for patients.

Masliah said it's also important to closely check whether speedier plaque reduction might increase the risk of a rare but 鈥� bleeding and swelling in the brain.

Alzheimer鈥檚 isn鈥檛 the only target. Other researchers are testing if breaching the blood-brain barrier could allow more chemotherapy to reach brain tumors, and ways to target other diseases.

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The Associated Press Health and 国产诱惑福利 Department receives support from the Howard Hughes Medical Institute鈥檚 国产诱惑福利 and Educational Media Group. The AP is solely responsible for all content.