Ashwin Vasan, MD, PhD, is an Internal Medicine physician who works as an Attending Physician at our East New York Health Hub and East New York / Dr. Betty Shabazz Health Center. He treats adults 18 and older.

Dr. Vasan earned his undergraduate degree in Economics and Pre-Medicine from the University of California, Los Angeles in 2001. He received his Medical Degree in Internal Medicine from the University of Michigan in 2011. He completed his residency in Internal Medicine/Primary Care at NewYork-Presbyterian Hospital in 2014.

Dr. Vasan is fluent in English and Spanish, and conversational in Tamil and French.

Nadine Osorio, RD, CDN, is a board-certified Registered Dietitian who works as a Nutritionist at our Williamsburg Center. She speaks English and some Spanish. Nadine completed her Master’s in Nutrition at Hunter College, CUNY, in 2024.

Nutritionist

Nicole is a board-certified Registered Dietitian-Nutritionist. She sees patients at our Washington Heights Health Center in Manhattan. Nicole completed her graduate degree at NYU and her dietetic internship at the James J. Peters Bronx VA Medical Center. She received her BA in Sociology from the University of Washington.

Family Nurse Practitioner Fellow

Isadora Kagan, FNP-BC is a Family Nurse Practitioner who works as a FNP Fellow. She treats patients at CHN Washington Heights. Isadora completed an undergraduate degree in Studio Art at Smith College in 2011, her Masters Degree in Nursing at Columbia University in 2021, and her Doctorate in Nursing Practice as a Nurse Practitioner at Columbia University in 2025.

Family Nurse Practitioner, Medical Director

Stephanie Chambers, FNP, DNP-BC is a Medical Director and clinician at CHN Washington Heights. Dr. Chambers completed an undergraduate degree in Nursing at The College of New and completed her Masters and Doctor of Nursing Practice at Pace University. Dr. Chambers is fluent in English.

Jacinth Ramsay-Green is a board-certified Family Nurse Practitioner. She holds a graduate degree in nursing from George Mason University and a graduate degree in public health from New York University.

Forensic Psychiatrist, Clinical Director of Psychiatry

Amilcar Arnaldo Tirado, MD, MBA, FAPA is a Forensic Psychiatrist who works as the Clinical Director of Psychiatry. He treats patients at our Harlem and Lower East Side locations. Dr. Tirado completed an undergraduate degree in International Relations at Union College in 2002, completed a master’s degree, an MBA in Healthcare Administration at Union Graduate College in 2005, and completed his Medical Degree at Ross University School of Medicine in 2010. Dr. Tirado completed his residency in Psychiatry at Lincoln Medical Center in 2017. He completed his fellowship in Forensic Psychiatry at SUNY Upstate in 2018. In 2019 he became a Fellow of the American Psychiatric Association, an honor which recognizes psychiatrists for their dedication to the profession. Dr. Tirado is fluent in English and Spanish.

Dr. Tirado believes in creating a safe, supportive space where patients feel heard, understood, and empowered in their mental health journey. He values collaboration, cultural sensitivity, and insight-oriented care to help individuals better understand their thoughts, emotions, and behaviors.

With experience across outpatient clinics, psychiatric emergency rooms, inpatient units, and partial hospitalization programs, Dr. Tirado has worked extensively with diverse populations. He has served as an Assistant Clinical Professor of Psychiatry at Weill Cornell Medicine, served on various hospital and professional society committees, published several articles, and delivered numerous presentations on a range of psychiatric issues,

Ann Grogan, PMHNP-BC is a licensed Psychiatric Nurse Practitioner who works as the Deputy Director of the Psychiatry Nurse Practitioner Fellowship Program at CHN. She also treats patients at several of the CHN health centers. Ann completed an undergraduate degree (BS) in Nursing at Columbia University in 2005 and completed her Nurse Practitioner Degree in Psychiatry (MSN) at CUNY-Hunter College in 2011. She is primarily fluent in English.

Ann has 20+ years of experience in the field of inpatient and outpatient psychiatry, including therapy and medicine prescribing/medication management. Ann has a wealth of experience therapeutically utilizing a person-centered approach including elements of psychodynamic, CBT, and Cognitive Behavioral Therapy.

She has treated clients to achieve overall well-being in regard to mental healthcare specifically with regard to depressive, anxiety, mood and psychotic disorders.

Ann has worked with many communities in NYC including, LGBTQ+ communities, victims of domestic violence, those with substance use disorders, and communities experiencing severe and chronic traumatic disorders.

Ann strives to understand the person as a whole and treat the root causes of mental health issues – while managing symptoms effectively.

Jay K. Varma is a medical doctor who works as a physician. He treats anyone over 18 years old at our Williamsburg and Crown Heights locations. Dr. Varma completed an undergraduate degree in history at Harvard College in 1993 and completed his medical degree at University of California, San Diego School of Medicine in 1997. He completed his internal medicine residency and chief residency at UCSD Medical Center in 2001. Dr. Varma is fluent in English. Dr. Varma is an expert in public health and the prevention and control of diseases, having published over 150 manuscripts in peer-reviewed journals.