Nature: controversial surgery claimed to reverse Alzheimer's symptoms

No summary can be written for this item: the source body was not supplied. The input contains only the headline — ‘A controversial Alzheimer’s surgery is said to reverse symptoms’ — repeated as the article text, with no reporting, no description of the procedure, no data, and no named sources. Writing 2-3 paragraphs from that alone would mean fabricating medical claims about an unproven, contested surgery, which I won’t do.