In the law firmsRopes & Gray LLP advised Cressey and Company LP, a private equity firm with more than $1 billion in health-care investments, in its acquisition of a majority ownership position in StatLab Medical Products in McKinney, Texas, from Prairie Capital LP.StatLab is a developer and manufacturer of diagnostic supplies for the anatomic pathology laboratory business. The transaction was announced on June 8.The Ropes & Gray attorney group included private equity partner Neill P. Jakobe, finance partner …