The data didn’t make sense. Five years ago, University of Maryland researcher Alisa Morss Clyne was studying pulmonary hypertension — a type of high blood pressure that affects the arteries in the lungs — in human cells she had cultured in her lab. But the results she was seeing just didn’t stack up. “We had these huge error bars. It didn’t make any sense,” she said. “And we said, OK, let’s just graph it by male versus female, and what we found was really interesting.” The blood vessels in the lungs of people with pulmonary hypertension take up more glucose, and she found the female cells metabolized the glucose in way that changed a protein that was critical to blood vessel function.