After several strokes, my uncle's behavior is inappropriate -- what can we do?

My uncle has suffered several strokes in the last six years. Physically, he has recovered and is fairly independent. However, he has gone from a charming intelligent man who was always very respectful of women to constantly leering and making sexually inappropriate conversation. It's bad enough at home, but a family outing with him to a restaurant, bank or grocery store is mortifying for all, especially my poor aunt. He will openly turn to stare at women as they walk by and flirts constantly expressing specifics (without profanity). We are not prudes, but his behavior and commentary is extremely offensive. Young female relatives are starting to avoid him,and no one brings a future in-law around. He would be mortified to know he's behaving this way, but it's getting worse, not better. It's like there are no controls in place, and he seems bewildered when we try to discuss it. Is anyone else dealing with this, and how are you handling it? I am also starting to worry about legal consequences.