Michael Hudson was named CFO and EVP of HealthPlan Holdings. He was previously head of care management operations for Aetna. HealthPlan is a Water Street Healthcare Partners‘ portfolio company.

HealthPlan Holdings Inc., a provider of services to insurers, has acquired Zenith Administrators Inc. Financial terms of the deal were not released. HealthPlan is backed by private equity firm Water Street Healthcare Partners. The firm is based in Chicago.

Chicago-based Water Street Healthcare Partners has added three new vice presidents to support its portfolio of healthcare companies: Hilary Dexter, Greg Robitaille and Mike Brennan. Dexter will lead executive recruiting; Robitaille will spearhead corporate development for Water Street’s companies. Brennan will identify and execute new investments, the company said in a release.

Bound Tree Medical, a supplier of emergency medical supplies and equipment to the pre-hospital market, has acquired Missouri-based Alliance Medical. Terms of the deal were not released. Alliance Medical is a distributor of emergency medical services products, supplies, equipment and clothing. Bound Tree Medical is backed by private equity firm Water Street Healthcare Partners.

Chicago-based Water Street Healthcare Partners has acquired MarketLab Inc., a distributor products to the clinical laboratory, hospital nursing and magnetic resonance imaging markets. The company is headquartered in Caledonia, Mich. Water Street said that it is committing up to $70 million of equity financing to both acquire, and grow, MarketLab.

PLUS Diagnostics, which is backed by Water Street Healthcare Partners, has appointed David Pauluzzi as its CEO. Pauluzzi has been PLUS Diagnostics’s president and COO since 2008. Tim Brodnik, who has been serving as PLUS’s executive chairman, will continue in this role.

Precision Dynamics Corp., which is backed by Water Street Healthcare Partners, has acquired the St. John Cos. Financial terms were not announced. Santa Clarita, Calif.-based St. Johns Cos. makes and distributes labels, patient identifications, medical imaging and medical record products to U.S. hospitals. Precision Dynamics, of Burr Ridge, Ill., provides healthcare wristband and labeling systems. Water Street is a Chicago PE firm.Harris Williams, an investment bank, advised St. John.

Chicago-based private equity firm Water Street Healthcare Partners will buy OraPharma from personal care conglomerate Johnson & Johnson. Specifics on the transactions were not disclosed and the PE firm will install former Janssen Pharmaceutica President Janet Vergis to serve as CEO of its latest acquisition.

Chicago-based firm Water Street Healthcare Partners has acquired a majority stake in benefit management company New Century Health. Financial terms of the deal were not released. Water Street said that it will work to expand the company’s services to a broader base of payers and patients across the U.S.