Valerie A. Clark has been named vice...

Valerie A. Clark has been named vice president of marketing and sales for National Health Care Systems Inc. She had been department director since 1989. Previously she was a senior sales manager with Johnson & Johnson in the McNeil consumer products division, and before that she was a manager with the Westwood pharmaceuticals division of Bristol Myers. National Health Systems, based in Irvine, owns DentiCare, which offers prepaid dental plans.