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The Division of General and Gastrointestinal Surgery has a long and distinguished history of scientific advancement. Dr. Francis D. Moore, the third Surgeon-in-Chief and Moseley Professor of Surgery at Harvard Medical School, was a pioneer in studying the impact of surgery on metabolism and founded the Laboratory for Surgical and Metabolic Research. This laboratory continues to be home to much of the division’s basic science researchers, who have made lasting contributions to the advancement of gastrointestinal and metabolic surgery. The division is also engaged in NIH-funded health services and education research, and we are active participants in multi-modality, disease-specific clinical trials through our role in the Dana-Farber/Harvard Cancer Center (DF/HCC). The overarching goal of our division is to improve the lives of our patients through innovation and advancements in clinical care, scientific discovery, and surgical education and training. The division promotes surgical innovation through the development of new pathways, procedures, devices and drugs. Our faculty hold several patents and are involved with startups focused on advancing the art and science of surgery.

Our faculty include presidents for many international societies including the Society for Surgery of the Alimentary Tract (SSAT), the American Society for Metabolic and Bariatric Surgeons ASMBS, the Association for Program Directors in Surgery (APDS), and the International Federation for the Surgery of Obesity and Metabolic disorders (IFSO). Our surgeons have research and scientific program leadership roles in many national organizations including the American College of Surgeons (ACS), the Society for Surgery of the Alimentary Tract (SSAT), the American Society for Metabolic and Bariatric Surgeons (ASMBS), the Association for Academic Surgery (AAS), and the American Society of Colon and Rectal Surgeons (ASCRS). Our faculty also include editors of Obesity Surgery and the Journal of Surgical Education as well as associate editors of the Journal of Surgical Research, and Digestive Disease and Sciences, with editorial board roles in many other journals.


Major areas of investigation include:

Health Services

  • Pancreatic cancer and pancreatitis (Stan Ashley)
  • Appendiceal and colorectal cancer outcomes (Ronald Bleday, Joel Goldberg, Nelya Melnitchouk)
  • Enhanced recovery protocols, Access, Utilization, Costs, Quality and Safety in Surgery (Ronald Bleday, Thomas Tsai, Edward Whang)
  • Global cancer care delivery (Nelya Melnitchouk)
  • Work-life balance, fertility and pregnancy challenges, and gender parity in surgical residents and early career practicing physicians (Erika Rangel)
  • Impact of sarcopenia on outcomes following geriatric emergency surgery (Erika Rangel)
  • Impact of bariatric surgery on cancer and inflammatory diseases (Eric Sheu)
  • Clinical outcomes of bariatric surgery and the impact on patient health (Ali Tavakkoli, Ashley Haralson Vernon)
  • Effectiveness of federal and state social distancing policies on the COVID-19 pandemic (Thomas Tsai)



  • Surgical education and training, patient safety, non-technical skills, coaching, and development of low-cost teaching models (Pardon Kenney, Brent T. Shoji, Douglas S. Smink, Edward Whang)


Basic Science

  • Role of host immunity and microbial metabolites in mechanisms of sleeve gastrectomy (Eric Sheu)
  • Mechanisms of diabetes resolution after gastric bypass surgery, focusing on the role of intestinal metabolism and portal signaling (Ali Tavakkoli)
  • Colitis-associated cancer, tumor microenvironment signaling (James Yoo)

In addition, the division hosts a collaborative NIH-funded site in multicenter studies aimed at investigating the following:

  • The association between oral health and infectious endocarditis and
  • The dental outcomes of head and neck cancer patients receiving radiation therapy


Erika Rangel, MD, MS

  • Brigham Education Institute grant – Evaluate the learning environment for medical students in surgery


Eric Sheu, MD, PhD

  • Blavatnik Foundation Accelerator & Q-FASTR Development Grants — Development of synthetic analogs of a sleeve gastrectomy-induced metabolite as a novel therapy for type 2 diabetes and obesity
  • American Surgical Association Fellowship — Characterization of a novel, gut-restricted metabolite that links the microbiome and the anti-diabetic effects of bariatric surgery


Douglas S. Smink, MD, MPH

  • CRICO grant – Creation of a pilot program investigating peer coaching by surgeons to optimize surgical performance and safety in the operating room
  • National Institute on Minority Health and Health Disparities (NIMHD) R01 – Evaluation of Cultural Dexterity Training Program for Surgeons: The PACTS Trial
  • NASA Human Research Program 80NSSC19K0745 – An experimental study in a space analogue simulation to understand variability in crew behavior during management of medical emergencies in space


Ali Tavakkoli, MD

  • NIH grant 5R01HL140574 – Role of Meal Timing in Efficacy of Bariatric Surgery in Obese Individuals
  • PCORI grant – Shared Decision Making for Bariatric Surgery in Patients with Severe Obesity


Thomas Tsai, MD, MPH

  • Ariadne Labs Spark Grant
  • Massachusetts Consortium on Pathogen Readiness (MassCPR) and Massachusetts Life Sciences Center (MLSC) – Update to the HGHI COVID-19 US Hospital Capacity Model: ICU Surge, Post-Acute Care Beds, and Survey of Mechanical Ventilator Supply


James Yoo, MD/ James Yoo, MD

  • The Bruce A. Beal and Robert L. Beal Fellowship, Brigham and Women’s Hospital Department of Surgery – Role of Bariatric Surgery in Colorectal Carcinogenesis

Faculty and Research Mentees Awards and News (2017 – current)

Mannick Research Award (Tammy Lo, David Harris)
MA-ACS Resident Research Award: Best Clinical Presentation (David Harris)
MA-ACS Resident Research Award: Best Clinical Presentation (Tammy Lo)
ACS Excellence in Research Award (David Harris)
ACS Resident Research Scholarship (David Harris)
NESS Oral Presentation Award (Tammy Lo)
American Surgical Association Foundation Fellowship (Sheu)
Society of Asian Academic Surgeons Junior Faculty Award (Sheu)
“Bariatric Surgery in a Pill” – National Media Coverage  (Tavakkoli)
Boston Globe Op-Ed on COVID-19 (Tsai)
The 2019 Leonard Tow Humanism in Medicine Award (Shoji)
Commission on Cancer Poster Recognition Award: Massachusetts Chapter of the ACS (Melnitchouk)
Best Clinical Poster Award: Massachusetts Chapter of the American College of Surgeons (Melnitchouk)
MGB Medical Education Research Award 2018 (Rangel)
NESS New Member Best Oral Presentation Awards, Years 2017 and 2019 (Rangel)

Research Staff

Tiegang Liu, PhD
Tammy Lo, MD (post-doctoral fellow)
James Luo, MD (post-doctoral fellow)
Renuka Subramaniam BVSc, PhD
Vanessa Welton, MD (health services research fellow)

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