The Application Process

Hey all! Im new to this forum but from what i can see it seems as though many of the users here are really helpful and informative regarding MBA programs and GMAT scores, so id figure i would post my info here and see if anyone has any guidance for me as to whether i will get into some of the programs i plan on applying to.

I am a hispanic student who attended UCSB and graduated with a 2.7 in Pharmacology (basically a major similiar to biochemistry). Im currently a Lab Manager for a cancer diagnostic lab (worked up from being a scientist for 2 years, have been a manger for over a year) where i coordinate the R&D for the staff (~3 scientists). I have a scientific paper about to be published in "modern Pathology" with my name on it regarding the diagnosis of a disease. My extracarricular's are softball and i also volunteer at a child abuse center. Im planning on having 3 letters of recommendation, 2 from PhD's in Pharmacology/Vetenarian Medicine and 1 from a Manager in retail where i used too work (Banana Republic, where i got promoted from Sales to stock supervisor because of my strong sales).ive been practicing with Kaplan 2008 edition CD's and my scores have been 540 and 620 on my 1st and second practice exams, respectivly. Im aiming for a 600 but secretly hope i get a higher score. My question is, what are the top tier schools i should be looking at with this type of background? Im looking at Northeastern, American University, and pretty much other schools with ~580 GMAT, but my question is, do you think im selling myself short? My GMAT is in 2 more weeks, so i really dont expect to skyrocket in the next 2 weeks (but you never know!) Any advice would be appreciated!