The present invention provides a method of treating ocular hypertension or glaucoma which comprises administering to an animal having ocular hypertension or glaucoma therapeutically effective amount of a compound represented by the general formula I; . The invention provides methods and compositions for stimulating an immune response against the bacteria. The magnetic circuit further includes a diaphragm and a coil having electrically conducting paths secured to the diaphragm. Gas seals are formed by the plastic to prevent gas in the mold cavity from reaching the exterior surface of the molded part during shrinkage of the plastic. Additionally, one or more locking mechanisms may be incorporated to prevent inadvertent needle sticks.