Our Clinic Staff
Jennifer Yance, Co-Founder ~ Executive Director
Jennifer Yance's work at the threshold of the organization has been a key element to its growth and accomplishments. With her impassioned determination and an aura of inspiration, she oversees and directs the fundraising, clinical, research, and education programs and gracefully guides the organization in serving its mission.
Jennifer’s business acumen, effective leadership, and deep commitment to healthy living contribute to her ability to help the organization reach its highest potential for serving humanity.
Tia Adachi ~ Practice Relations Manager
As our Practice Relations Manager Tia oversees daily clinic operations, ensuring alignment with the organization’s core values and business strategies. She collaborates closely with practitioners and staff to provide patients with exceptional support and care.
Tia has a robust background in healthcare management, with expertise in clinic operations and patient care. She is skilled in fostering meaningful connections among staff, practitioners, and patients, and is dedicated to building an inclusive, empowered, and collaborative environment. Her experience spans primary care, internal medicine, hospice, and naturopathic medicine, and she is passionate about multi-disciplinary, patient-centered care.
In her role, Tia brings significant experience in practice relations and a deep understanding of the Mederi Care model. Having worked closely for many years with Mederi Center’s founder, Donnie Yance, she offers a unique perspective and strong foundation in the clinic’s mission of walking alongside patients on their healing journey toward lifelong wellness. Her work is grounded in a commitment to compassionate care, team collaboration, and a unified vision for integrative medicine.
Jennelle Mason ~ Executive Clinical Assistant to Donnie Yance and Practice Fulfillment Manager
Jennelle Mason serves two integral roles at Mederi Center. As Executive Clinical Assistant to Founder Donnie Yance, she provides high-level, compassionate support to Donnie's clientele. This role requires a thoughtful, attentive, and experienced professional—qualities Jennelle brings in abundance. With a strong background in management, clinical operations, and supporting naturopathic practices, she excels at creating positive, supportive environments that reflect the heart of Mederi’s mission. Her passion for natural healing and patient-centered care makes her uniquely suited to support our founder directly.
As Practice Fulfillment Manager, Jennelle oversees the clinic’s apothecary and order fulfillment departments with clarity, care, and a focus on quality. She brings strength in organization and team leadership and provides a solutions-oriented approach to ensure the smooth and accurate delivery of personalized formulations and protocols. Her work is essential to maintaining the integrity of each patient’s care plan, supporting both compliance and continuity. By cultivating a collaborative and responsive environment within the fulfillment team, Jennelle plays a key role in upholding the high standards of service that patients rely on throughout their healing journey.
Laura Macaluso ~ Client Liaison
Laura is the Client Liaison for Susan Saccomanno, ND, LAc, and has been a valued member of the Mederi Center team since 2022. She brings a strong background in health and wellness, including roles as a yoga instructor and as the Wellness Lead at a local natural foods and healthcare products store. Laura’s holistic perspective and commitment to patient care align seamlessly with Mederi’s integrative approach.
In her role, Laura serves as the bridge between Dr. Susan and her patients, managing the many administrative details that support an evolving and collaborative care relationship. Her work ensures continuity of care and helps facilitate the best possible clinical outcomes. With warmth, attentiveness, and professionalism, Laura provides the kind of thoughtful support that contributes to a positive and empowering healing experience.
Amanda Slaton ~ Client Liaison
Amanda is the Client Liaison for Dr. Kristin Roos, Dr. Rachel Stricker, and Dr. Jason Miller. She brings extensive experience in the healthcare field, where she has consistently demonstrated a strong commitment to patient-centered service. With a background in clinical management, Amanda excels in supporting daily operations, fostering positive staff relationships, and ensuring clear, compassionate communication between patients and practitioners.
Her expertise includes working with NDs, DCs, and LAcs, as well as medical billing specialization., along with specialized knowledge in medical billing. As a trusted liaison, Amanda skillfully manages the many details that support the connection between our physicians and their patients. She oversees administrative responsibilities that promote continuity of care and enhance clinical outcomes. With Amanda’s professionalism and dedication, patients receive attentive, personalized support—contributing to a smooth, positive healing experience.
Dana Aronson ~ Apothecary Manager, Client Liaison
With 15 years of experience in management and customer service, a Clinical Herbalism Certificate, and extensive experience working in multiple capacities in herbal medicine centers and apothecaries, Dana brings a wealth of talent to our team. Dana's prior experience includes teaching medicine-making at Berkeley Herbal Center, as well as working with healthcare practitioners to fill client formulas and overseeing orders and stocking of herbal medicines at Five Flavors Herbs in Oakland.
Dana is also an active volunteer in the community, including helping to set up herbal clinics through Mashh (Medicine for All Seeking Health and Healing) and other community service through Curbside Care Clinic and Klamath Siskiyou Herbal Alliance. As the manager for Mederi’s compounding apothecary, Dana is responsible for all aspects of Mederi’s apothecary operations such as having knowledge of all apothecary products and procedures, custom compounding for patients and practitioners, ordering/receiving inventory, quality control and procurement, and accurate record-keeping, ensuring AHPA Good Compounding practices are followed. In her role as Client Liaison, Dana is the bridge between Oscar Sierra and his clients, helping to support a positive practitioner-client relationship and successful clinical results. With her positive demeanor and passion for herbal medicine, Dana is a valued member of our clinic team.
Jeraldine Graham ~ Apothecary Herbalist
As a Certified Herbalist for our Apothecary, Geraldine is responsible for supporting all aspects of apothecary operations. This includes custom compounding of teas, tonics and topicals as stated on patient/client protocols, as well as compounding stock formulas formulated by our Founder and Lead Clinician Donnie Yance. Geraldine is also tasked with maintaining knowledge of apothecary products, inventory restocking and tracking, accurate record keeping, and upholding the highest standard of industry compliance.
Geraldine is an avid and passionate student of herbal medicine. She has a strong foundation in Western Herbalism through her studies with the Acorn School of Herbal Medicine and the North American Institute of Medical Herbalism. Geraldine is currently certified as a Vitalist Herbalist and is engaging in further studies, including a clinical residency.
Gretchen Roberts ~ Order Management Specialist
Gretchen has been with Mederi Center since 2004 and is intimately aware of the need for timely, accurate, rapid, actionable, and documented communication between practitioners and their clients/patients. This is especially so when it comes to knowledgeably answering order fulfillment questions about products, following Apothecary Policies & Procedures, overseeing quality assurance checks on all product orders, and archiving and maintaining accurate and up-to-date practitioner/client account information.
Diane Chasmar ~ Clinic Coordinator
Diane joined the Mederi Center team in 2019. She is an integral part in ensuring that our clinic operations run smoothly and successfully, performing a variety of administrative support and client/patient service tasks. Diane is also the hub of our client/patient reception. With her friendly, gracious demeanor and efficient work ethic, Diane handles phone and email communications, schedules appointments for multiple practitioners, and also serves as a product shipping coordinator.
Diane plays a supportive role for many aspects of our organization, and strives to create a streamlined customer service experience. As the first contact for people inquiring about our patient services, we greatly appreciate Diane's kind and compassionate personality. Diane's previous professional experience includes business management, and 25 years in the publishing industry including graphic design, and photography.
In Loving Memory of Zeny Yance
Zeny Yance passed away January 26, 2016 at Rogue Regional Medical Center in Medford, OR at the age of 60. Zeny worked at the Mederi Centre for Natural Healing for more than 20 years, and was devoted to a life of service helping others. She was a great friend to many and always worked with a sense of pride and purpose. Zeny embodies the spirit that the Centre was founded on and her memory will live on with us forever.
