Just about everyone knows someone — or is that someone — who has aches or pains, some forgetfulness or other age-related issue or disease. As the human body ages, it deteriorates: Bones grow brittle, muscles don’t recover as quickly, brains even begin to shrink. Johns Hopkins University has assembled a group of experts based at its Bayview Medical Center in Baltimore to accelerate work underway to better understand what’s causing these age-related problems, slow them or even fix them. It’s an ambitious collaboration among several Hopkins hospital and university departments called the Human Aging Project.