He worked at University of Texas Southwestern Medical Center and served as chair of the department of medicine for 36 years.
[5] He graduated from high school at age 16, and studied literature at New York University, receiving his bachelors of arts in 1940.
[5] While there, he was called to Dachau to testify at the trial of a Nazi physician accused of human experimentation resulting in the deaths of 40 prisoners.
[4] When Seldin joined UT Southwestern, it was the newest medical center in the country, and was housed in a dilapidated army barracks.
[6] Within 6 months, the physician who recruited him left, leaving him as the only full-time faculty member of the medical center, and earning him the position of chair by default.
[2] Many of the students and faculty he recruited have become leaders in medicine, including Dan Foster, Manuel Martinez-Maldonado, Jean Wilson, Kern Wildenthal, Roland Blantz, Floyd Rector, Helen Hobbs, John Fordtran, John Dietschy, and Michael Brown and Joseph Goldstein, who together won the 1985 Nobel Prize in Physiology or Medicine.
[9] During his leadership, the once-decaying school was transformed into a world-class medical center with five Nobel laureates and an endowment of more than $1 billion.
"[9] He and Robert Tarail first described how glucose behaves as a solute causing water to exit cells due to the change in concentration gradient in uncontrolled diabetes.
In collaboration with others, he has published research on a variety of topics in the field of nephrology, including the factors affecting acid-base homeostasis, the role of the kidney in determining osmolarity and volume of blood, and the basic functions of renal tubules.