Advocates are calling for increased safety measures after a man allegedly attacked a Lowell nurse with a fire extinguisher over the weekend. Officers responding to Lowell General Hospital were told the nurse was sitting at her station when a patient used a fire extinguisher to hit her twice in the back of the head, and chased a second nurse before security tackled him, police said. Jean Paul Durand, 65, of Lowell, was arraigned in Lowell District Court on two counts of assault and battery with a dangerous weapon.