Medical Student Research Fellowship for Summer 2003

Mentor: Rod J. Rohrich, M.D./ Jeffrey Kenkel, M.D./Spencer A. Brown, Ph.D./James Chao, MD
Department: Plastic Surgery
Room number: G7.254
Mail Code: 9132
Phone number: 648-2482
E-mail: spencer.brown@utsouthwestern.edu
Project title: Novel suture material for accelerated wound healing

Human subjects IRB approved project number (where applicable):

Animal subjects IRB approved project number (where applicable):

Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects) BASIC

Brief Description of Project:

Project 1

Surgical sutures continue to be the most frequently used biomaterial for wound closure and tissue approximation. Suture is foreign material and can initiate an inflammatory response. Suture material may be made of 'cat gut', newer synthetic polyglycolic acid derivatives, nylon, silk, or stainless steel. The first two examples are absorbable and the others must be removed. Fine suture material and minimal tightening limit any additional tissue damage, inflammation and scarring. In addition, the sutures require tied secured knots, which often entail challenging techniques and can be time-consuming. The knot further impedes wound healing, constricts blood flow, distorts tissue, and can cause scar formation.

We will determine if antibodies to inflammatory agents can be used as a coating on sutures to decrease the inflammatory reactions known to occur during wound healing. We will use absorbable suture materials and utilize several, established mechanisms to bind proteins to biomaterials. If we are successful, we will submit a IACUC protocol and try these modified sutures in our rat skin wound healing model.

Project 2

Wound healing is a natural restorative response to tissue injury. Healing is the interaction of a complex cascade of cellular events that generate resurfacing, reconstitution, and restoration of the tensile strength of injured skin. Under the most ideal circumstances, healing is a systematic process, traditionally explained in terms of 3 classical phases: inflammation, proliferation, and maturation. Clot forms and cells of inflammation debride injured tissue during the inflammatory phase.

We have a laser-induced wound using surgical tissue form the IRB-approved study that allows us to detrmine keratinocyte migration rates. Bacteria is known to interfere with wound healing times. We would like to investigate at what dose range (CFU/mg of tissue) Staph. Aureus and other skin-associated bacteria decrease epithelization in our wound healing model.

Project 3

Laser resurfacing is definitely a surgical process and requires a significant post-operative healing course. It may take 10-14 days for skin to completely heal, and there is always redness for several weeks afterwards. Because different areas of the face have thicker or thinner skin, they require different intensities of treatment. Non-facial skin heals less predictably than the face. Pigmentary alterations (change in skin color) may occur after laser resurfacing and may be unpredictable, but the incidence is much lower than with dermabrasion or chemical peel. When done properly, laser resurfacing is very effective at removing wrinkles and certain types of acne scars.
The extent of cellular damage to necrosed cells is easily identifiable by histological analyses. However, it is not well characterized to the skin zone or depth of damage from the heat -associated laser treatment. We plan to perform immunohistochemical analyses for HSP-74, the heat-inducible protein, on human skin tissues treated with various clinical laser protocols.

Project 4 title: PDGF-C expression in human wounds

Human subjects IRB approved project number (where applicable): USE VA IRB #01-088

Animal subjects IRB approved project number (where applicable):

Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects): Patient based

Brief Description of Project:

This patient -based project will examine the expression of PDGF-C in human wound margins. As a putative stop signal, PDGF-C expression was decreased in a preliminary study. The focus of this study will be to assist a medical research fellow in the collection of specimens from VA spinal cord injury patients. The RT-PCR analyses of these samples will provide an insight in to PDGF-C expression in control, non-wounded and wounded sites. IN addition, we will determine the expression of gas (growth arrest genes) genes and determine if wound repair is correlated to the relative expression of PDGF-C and gas genes.

Project 5 title: Evaluation of the Ideal Hand

Human subjects IRB approved project number (where applicable): to be submitted

Animal subjects IRB approved project number (where applicable):

Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects)

Brief Description of Project:

Subjects often inquire to rejuvenate the second most viewed part of the body - the hands. The implication of such a request is that a subject's hands may be altered to approach an image or impression of the "ideal, youthful hand" There are physical characteristics that are associated with youthful hands. To date, no study has examined systematically the anatomical dimensions and relationships of the ideal hand - a model that will be derived from the responses of a number of medical and lay persons viewing 100+ photographs of hands.

Collection of photographic and xray data will be performed as well as compiling survey results and statistics.

Project 6 title: Cytokine levels in wound fluid

Human subjects IRB approved project number (where applicable): USE VA IRB #

Animal subjects IRB approved project number (where applicable):

Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects)

Brief Description of Project:

This patient - based project will examine cytokine levels in human wound margins. Using microdialysis as a technique for collecting wound fluid, cytokine levels (TNF alpha, IL-8) will be determined by ELISA techniques currently operational in the laboratory. Spinal cord injury patients from the Veterans Administration will be consented and wound fluid and biopsies will be collected from pressure ulcers.

Previous Research Activities or Publications with Medical Students:

We have mentored over ten medical students and two high school teachers as well a SMU undergraduate and have 6 full time research fellows at the current time.

Return to UT Southwestern Homepage

Return to Student Research Projects Index