John Langell, MD, PhD, MPH completed his surgical training at Stanford University Medical Center and completed advanced training in Space and Aerospace Medicine with NASA at the Johnson Space Center in Houston, Texas. He has specialized expertise in the treatment of diseases of the upper gastrointestinal tract, biliary tract, and endocrine system (thyroid, parathyroid and adrenal glands). He is board certified in general surgery and board eligible in Space and Aerospace Medicine. His clinical focus is in the application of advanced minimally invasive surgical techniques in laparoscopic surgery with special focus on diseases of the stomach, intestines, liver, gallbladder, pancreas and biliary tree.