Dr. Aung received his undergraduate degree (BSc) majoring in chemistry and physiology from the University of Alberta, Canada. He then completed his studies in medicine at UNIBE in the Dominican Republic where he graduated as Doctor of Medicine with magna cum laude. He went on to train for his post-graduate studies at Good Samaritan Internal Medicine residency program in Cincinnati, Ohio from 2006 to 2009. Both during his undergraduate and in his post-graduate years, he was actively involved in community services such as the Ecology group in UNIBE and serving as a medical volunteer in a medical mission to Honduras as part of the Holy Savior group. He achieved board certification in Internal medicine upon graduation from Internal Medicine residency in 2009.
After his formal training, Dr. Aung went on to join a large multi-specialty group in an under-served area of central New Hampshire from 2009 to 2013 practicing traditional Internal medicine/Primary care in both inpatient and outpatient settings. He moved to Texas in 2013 with his family to pursue a career in the care of the elderly in Medicare Advantage population for a year before being admitted to a fellowship training in Geriatrics Medicine at UT Health Science Center in 2014. He became board certified in Geriatrics Medicine in 2015. He then spent the next six years of his career in Wellmed from 2015 until 2022 also in the care of the elderly Medicare population.
In his spare time, he loves to travel the world with his family visiting historic sites and picking up new languages. He also likes the outdoors including hiking and camping. His favorite sports and hobbies include Swimming, Tennis, Aikido, Jujitsu and firearms training amongst others.
He is an avid student of medical economics and innovative healthcare delivery models exploring alternate ways of making healthcare more cost effective while optimizing quality and improving provider satisfaction at the same time. He also precepts for Nurse practitioner students, medical students and Internal medicine residents with UT medical school. He is fluent in English, Spanish and Burmese.
Dr. Ranjani Amin obtained her medical degree from Touro University in Nevada before completing her family medicine residency at Broward Health Medical Center in Ft. Lauderdale, Florida. She then moved back to her home state of Texas as an attending at Baylor College of Medicine followed by a short stint at Village MD prior to joining MacGregor in 2022.
Dr. Amin grew up in San Antonio and was a patient at MacGregor starting in high school before gaining her Bachelor of Science in Biology at the University of Texas at Austin. It was that patient experience that inspired her to pursue medicine. She was moved by the care she received and wanted to pay it forward as a provider and has since focused on preventative medicine and women’s health.
In her free time, she loves spending time with her family, traveling and baking sweet treats. She is fluent in Telugu and can understand Kannada.
Dr. Ana Rodriguez is a graduate from the College of Human Medicine, Michigan State University in 1991. She completed her Internal Medicine Residency at the University of Texas Health Science Center San Antonio(UTHSC-SA) in 1994. After finishing residency she decided to join the Faculty of the UTHSC-SA as Instructor of Medicine. In 1996 she moved on to MacGregor Medical Association (MMA) as Senior Physician Leader. She kept her title of Clinical Assistant Professor by mentoring and teaching medical students over the last 30 yrs. After 4 years of being at MMA she became the only female that help found current MacGregor Medical Center of San Antonio. Her area of expertise as Internist is Women's and Geriatric Health care. Her pride and joy are her children and grandchildren. She loves to travel and remains physically fit by training several days per week as well as doing Reformer Pilates.
Dr. Rodriguez graduated in 1994 from Ponce School of Medicine where he was inducted into the Alpha Omega Alpha Honor Medical Society. He completed a residency in Internal Medicine at Washington University Medical Center in St. Louis, Missouri, and later became Board Certified in Internal Medicine. He moved to San Antonio in 1994 and became part of the MacGregor Medical family. He and his wife, a dentist, have three lovely children. Dr. Rodriguez has special interests managing diabetic, obese and hypertensive patients as well as patients with allergic rhinitis. He has been featured yearly as one of San Antonio’s best internists in San Antonio Magazine’s “Best Doctors”. Dr. Rodriguez is fluent in Spanish and speaks some French and Italian.
Born in the US and raised in Colombia, Dr. Roldan earned his medical degree from The University of Antioquia School of medicine in Medellin in 1991. He holds a full medical license in this country. He spent a year in an Infectious Disease research fellowship at The University of Texas in San Antonio, then completed a residency at Baylor College of Medicine in Houston, including his last year as a Chief Resident. He followed with a fellowship in Palliative Care at the University of Texas Health Science Center – San Antonio being one the first fellows in this field in the US. He is Board certified by the American Board of Family Medicine, practices family medicine as well as palliative care. He is one of the founding partners at Macgregor medical center, he is fully bilingual in English and Spanish, has been practicing primary care at our clinic since July 1999 seeing patients 17 and older. He has multiple interest but his strong focus is on preventive medicine and fostering health with emphasis on age appropriate immunizations, weight loss, dietary counseling and exercise. Outside medicine Dr. Roldan enjoys spending time with his wife, an endocrinologist and on his free time loves to ride his motorcycle through the Texas hill country.
Dr. Jose Sanchez has been providing internal medicine care with MacGregor Medical for over 30 years. He is board-certified and serves as a Clinical Assistant Professor at UT Health. Dr. Sanchez completed his internal medicine residency at UT Health Science Center in San Antonio and pursued his medical studies in Puerto Rico. He is fluent in both English and Spanish.
Dr. Idalys Santos grew up in Puerto Rico and moved to North Carolina in 2010 to pursue her undergraduate studies in biology at the University of North Carolina at Greensboro. She went on to earn her medical degree from the University of North Carolina at Chapel Hill in 2018 and completed her residency training in Internal Medicine at Moses Cone Hospital in Greensboro, North Carolina. After her training, Dr. Santos relocated to San Antonio, where she has been practicing as a primary care physician since 2021.
Dr. Santos’ clinical interests include preventive medicine and the management of chronic medical conditions such as diabetes and cardiovascular diseases. She is passionate about partnering with her patients to create individualized care plans that promote long-term health and overall well-being through education, prevention, and evidence-based treatment.
Fluent in both Spanish and English, Dr. Santos is dedicated to providing compassionate, culturally sensitive care to a diverse patient population.
Outside of medicine, Dr. Santos enjoys spending time with her loved ones and her dogs. She also loves traveling, reading, and challenging herself with jigsaw puzzles.
Dr. Vizcarra joined MacGregor in 2019 and we are so glad to have her! Originally from Mexico, she attended medical school at the Universidad Autonoma of Coahuila in Torreon, Coahuila, Mexico, then completed her medical training in Philadelphia, Pennsylvania. A residency in Family Medicine at Drexel University was followed by a fellowship in Geriatrics at Thomas Jefferson University.Dr. Vizcarra’s interest in education landed her a position with Texas Tech University Health Science Center Permian Basin Campus in Odessa, Texas. She started as an Assistant Professor, and directed a Family Medicine Residency program as well as a Geriatrics program, leading to an Associate Professor status before moving to San Antonio. In San Antonio, she began a solo practice and later joined a Palliative Medicine Program.Dr. Vizcarra loves primary and preventative care, with a passion for Geriatrics and addressing health disparities. She is an active member of the Texas Association of Family Medicine, The Texas Medical Association, and the American Geriatrics Society, and is a Fellow of the American Association of Family Medicine.Her favorite hobbies are reading, traveling, and running. She loves family gatherings and spending time with family and friends.
PA Jeremy Diaz joined MacGregor in 2020 after practicing Primary Care Medicine from San Antonio to the southernmost Rio Grande Valley, Texas regions. Since 2006 Jeremy has worked to empower patients in understanding treatment and preventative care options for healthful living from his years as a Nursing Aid, Medical scribe, and Medical research. His patient philosophy is building trust for long-term relationships, bringing multicultural competence with moderate Spanish language fluency having been raised on the Texas-Mexico border among under-served, indigent, and undocumented populations. PA Diaz completed his Master of Science in Physician Assistant Studies from UT Rio Grande Valley 2017 with a thesis on Acute Anxiety and Bachelor of Science from UTSA Honors College in Biology. Jeremy is board certified by the National Commission on the Certification of Physician Assistants (NCCPA) Board and has earned certifications in Advanced Cardiac Life Support (ACLS) and Basic Life Support (BLS). PA Diaz loves exploring the Hill Country with his wife and supporting local San Antonio coffee shops where you’ll see him doting on his Boston terrier while sipping Cold Brew Coffee. In his spare time, he can also be found making and delivering home-made Mexican meals for Veteran and Homeless residents in South Texas.
PA Sabrina Sanchez was born and raised here in San Antonio, Texas. She has always had a passion for expanding access to healthcare, and she is very thrilled to be a part of the MacGregor team to help serve her home community.
PA Sanchez received her Master of Physician Assistant Studies from Hardin Simmons University in Abilene, where she was awarded Best Overall PA Student. She has also received her Doctorate of Medical Science (DMSc) degree at Hardin-Simmons University, where she advanced her knowledge and training in advancing clinical practice, healthcare leadership, and patient education. She earned her Bachelor of Biomedical Sciences from Texas A&M University in College Station. Sabrina is board-certified by the National Commission on Certification of Physician Assistants (NCCPA).
In her free time, she loves to travel, watch Aggie football, attend Spurs games, do puzzles, and spend time with friends and family.
Juana M. Gaona is a graduate from the University of Texas Health Science Center at San Antonio with her Doctorate in Nursing Practice. She also earned her Master of Science in Nursing (MSN) in Nurse Practitioner and specialized in Family Practice. Upon graduation with her Family Nurse Practitioner (FNP), she was inducted in Sigma Theta Tau International Honor Society and Golden Key Honor Society. She is nationally certified by the American Academy of Nurse Practitioners (AANP) and holds a certification from the Texas Board of Nursing as a Advanced Practice Registered Nurse (APRN).
NP Gaona has practiced in various health care settings and has had the pleasure to have served rural and underserved patient populations of South Texas which included the entire age spectrum. She brings a wealth of experience and training to MacGregor Medical Center. She has worked at long term care facilities, nursing homes, surgical and medical intensive care units as a charge nurse, post anesthesia care units, and pediatrics.
NP Gaona developed her love to assist in the healing of others at a very young age thus commencing her medical profession early in life. Her practice philosophy is based on culturally competent patient-centered care through a holistic approach.
In her free time, NP Gaona enjoys spending time with her family, she enjoys cycling, running and hiking.
9969 Fredricksburg Road
San Antonio, TX 78240
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