The bulk of what remains in Rochester R&D is not pharma, so I find it hard to see how buying a GI pharma company would affect vision care.
But that is just my opinion.
Honestly, with how small Salix's (employee) footprint is, I would be surprised if there is anyone left in North Carolina at the end of 2015. Any Salix employees who work at headquarters (non-sales) will likely be Let go (the majority) or sent to NJ or Rochester.