CAIRO (AP) — In a remote pocket of northern Yemen, many families with starving children have nothing to eat but the leaves of a local vine, boiled into a sour, acidic green paste. International aid agencies have been caught off guard by the extent of the suffering there as parents and children waste away. The main health center in Aslam district was flooded with dozens of emaciated children during a recent visit by the Associated Press. Excruciatingly thin toddlers, eyes bulging, sat in a plastic washtub used in a make-shift scale as nurses weighed each one. Their papery skin was stretched tight over pencil-like limbs and knobby knees. Nurses measured their forearms, just a few centimeters in diameter, marking the worst stages of malnutrition.