Dr. Barnes is a board-certified dermatologist who provides care at Stanford Health Care Dermatology Clinics in Redwood City and Emeryville. She is also an Instructor of Dermatology within the Department of Dermatology at Stanford School of Medicine.

Dr. Barnes specializes in diagnosing and treating a broad range of skin conditions, including hidradenitis suppurativa, skin cancer, and conditions that disproportionally impact people of color. As Co-Director of the Stanford Medicine Hidradenitis Suppurativa Specialty Clinic, her clinical focus includes maximizing awareness of and care options for this condition. Dr. Barnes is also the Founding Director of the Stanford Medicine Skin of Color Program and Director of Advocacy, Equity, and Inclusion in the Department of Dermatology at Stanford Medicine.

Dr. Barnes’ clinical research focuses on identifying the underlying mechanisms associated with the onset and progression of hidradenitis suppurativa. These efforts include research on access to care among different patient populations and studies identifying immune-mediated characteristics of the condition. She is also engaged in efforts to promote broader and more effective outreach initiatives to drive melanoma awareness among minority populations and young children.

Dr. Barnes has published her work in numerous peer-reviewed journals, including the Journal of Investigative Dermatology, JAMA Dermatology, and the Journal of the American Academy of Dermatology. She has also been an invited guest speaker at national and international meetings, including those for the Society of Investigative Dermatology and the World Congress of Dermatology.

Clinical Focus

  • Dermatology

Academic Appointments

Honors & Awards

  • Magna Cum Laude, Harvard University

Professional Education

  • Residency: Stanford University Dermatology Residency (2023) CA
  • Internship: Santa Clara Valley Medical Center Internal Medicine Residency (2020) CA
  • Medical Education: Stanford University School of Medicine (2019) CA
  • MD, Stanford University, Medicine, Bioengineering Scholarly Concentration (2019)
  • Bachelor of Arts, Harvard University, Molecular and Cellular Biology, Japanese Language Citation (2013)

All Publications

  • Longitudinal remote monitoring of hidradenitis suppurativa: a pilot study. The British journal of dermatology Fonjungo, F. E., Barnes, L. A., Cai, Z. R., Naik, H. B., Eid, E. S., Aleshin, M. A., Nava, V., Johnson, T., Chren, M., Linos, E. 2023

    View details for DOI 10.1093/bjd/ljad385

    View details for PubMedID 37823362

  • Patient Perspectives of Health System Barriers to Accessing Care for Hidradenitis Suppurativa: A Qualitative Study. JAMA dermatology Barnes, L. A., Shukla, N., Paul, M., de Vere Hunt, I., Halley, M. C., Linos, E., Naik, H. B. 2023


    Patient-perceived barriers to hidradenitis suppurativa (HS) care are poorly understood. Understanding health care barriers is a critical first step toward improving care for this population.To characterize the health care experiences of people living with HS, including perceived barriers and facilitators to health care access, and to elucidate potential associations among these barriers and facilitators, health care access, and disease activity.In this qualitative study, an inductive thematic analysis was conducted on 45 in-depth, 60- to 90-minute semistructured interviews of 45 people with HS from diverse sociodemographic backgrounds that took place between March and April 2020. Individuals were eligible if they could speak English, were 18 years or older, and were diagnosed with HS. A diagnosis of HS was confirmed through physician diagnosis or through self-reported, affirmative response to the validated screening question, "Do you experience boils in your armpits or groin that recur at least every six months?"Interviews were audio recorded and transcribed verbatim. A modified grounded theory approach was used to develop the codebook, which investigators used for inductive thematic analysis.Among the 45 participants included, the median (IQR) age was 37 (16) years, 33 (73%) were female, and 22 (49%) were White. There were 6 interrelated themes associated with participant-perceived barriers to accessing HS care: (1) bidirectional associations of disease activity and employment, (2) association of employment with health care coverage, (3) association of health care coverage with costs and perceived access to care, (4) association of costs with access to patient-centered care, (5) health care professional attitudes and knowledge influence patient-centered care and perceived access to care and disease activity, and (6) health system characteristics influence patient-centered care and associated costs, perceived access to care, and disease activity.This qualitative study highlights themes that generate a conceptual model for understanding barriers that may act synergistically to limit health care access and influence disease activity. The disease activity of HS may be reduced when cycle elements are optimized. This study also highlights areas for future investigations and potential systems-level changes to improve access to patient-centered HS care.

    View details for DOI 10.1001/jamadermatol.2023.0486

    View details for PubMedID 37017984

  • Qualitative exploration of melanoma awareness in black people in the USA. BMJ open de Vere Hunt, I., Owen, S., Amuzie, A., Nava, V., Tomz, A., Barnes, L., Robinson, J. K., Lester, J., Swetter, S., Linos, E. 2023; 13 (1): e066967


    Although black patients are more likely to have advanced melanomas at diagnosis, with a 5-year survival rate among black patients of 70% compared with 92% for white patients, black people are generally not the focus of melanoma public health campaigns. We sought to explore awareness and perspectives of melanoma among black people to inform the development of relevant and valued public health messages to promote early detection of melanoma.Inductive thematic analysis of in-depth semistructured interviews.Interviews were conducted with participants via video software or telephone in the USA.Participants were adults from the USA who self-identified as African American or black. Recruitment flyers were posted around the San Francisco Bay Area and shared on our team Facebook page, with further participants identified through snowball sampling.We interviewed 26 participants from 10 different states. Overall, 12 were men and 14 were women, with a mean age of 43 years (range 18-85). We identified five key themes regarding melanoma awareness in black people: (1) lack of understanding of term 'melanoma' and features of skin cancer; (2) do not feel at risk of melanoma skin cancer; (3) surprise that melanoma can occur on palms, soles and nails; (4) skin cancer awareness messages do not apply to or include black people; and (5) Importance of relationship with healthcare and habits of utilisation.Analysis of these in-depth semistructured interviews illuminate the pressing need for health information on melanoma designed specifically for black people. We highlight two key points for focused public health messaging: (1) melanoma skin cancer does occur in black people and (2) high-risk sites for melanoma in black people include the palms, soles and nail beds. Therefore, public health messages for black people and their healthcare providers may involve productively checking these body surface areas.

    View details for DOI 10.1136/bmjopen-2022-066967

    View details for PubMedID 36631232

    View details for PubMedCentralID PMC9835941

  • Hidradenitis Suppurativa in Sexual and Gender Minorities: A Review and Considerations for Providers. Journal of the American Academy of Dermatology Gomez, J., Barnes, L. A., Yost, J. M., Gordon, J., Ginsberg, B. A., Aleshin, M. 2022


    The literature on hidradenitis suppurativa (HS) in sexual and gender minorities (SGM) remains sparse. This review article aims to discuss critical factors for providers to consider in LGBTQIA patients with HS, including associated comorbidities, gender-affirming hormonal therapy, squamous cell carcinoma, infections in HIV-positive patients, and creating a welcoming clinic for SGM patients.

    View details for DOI 10.1016/j.jaad.2022.03.008

    View details for PubMedID 35283243

  • Autoantibodies present in Hidradenitis suppurativa correlate with disease severity and promote release of proinflammatory cytokines in macrophages. The Journal of investigative dermatology Carmona-Rivera, C., O'Neil, L. J., Patino-Martinez, E., Shipman, W. D., Zhu, C., Li, Q., Kerns, M. L., Barnes, L. A., Caffrey, J. A., Kang, S., Kaplan, M. J., Okoye, G. A., Byrd, A. S. 2021


    Hidradenitis suppurativa (HS), also known as acne inversa, is a debilitating inflammatory skin disorder that is characterized by nodules that lead to the development of connected tunnels and scars as it progresses from Hurley stage I to III. HS has been associated with several autoimmune diseases, including inflammatory bowel disease (IBD) and spondyloarthritis. We previously reported dysregulation of humoral immune responses in HS, characterized by elevated serum total IgG, B cell activation and antibodies recognizing citrullinated proteins. Here, we characterized IgG autoreactivity in HS sera and lesional skin compared to normal healthy controls using an array-based high-throughput autoantibody screening. The Cy3-labeled anti-human assay showed the presence of autoantibodies against nuclear antigens, cytokines, cytosolic proteins, extracellular matrix proteins, neutrophil proteins, and citrullinated antigens. Most of these autoantibodies were significantly elevated in stage II-III in HS sera and stage III in HS skin lesions compared to healthy controls. Furthermore, immune-complexes containing both native and citrullinated versions of antigens can activate M1 and M2 macrophages to release pro-inflammatory cytokines such as TNF-alpha, IL-8, IL-6 and IL-12. Taken together, the identification of specific IgG autoantibodies that recognize circulating and tissue antigens in HS suggests an autoimmune mechanism and uncovers putative therapeutic targets.

    View details for DOI 10.1016/j.jid.2021.07.187

    View details for PubMedID 34606886

  • The sunscreen for kindergarteners (SKIN) study trial protocol. Contemporary clinical trials Lee, G. H., Bae, G. H., Barnes, L. A., Pol-Rodriguez, M. M., Ransohoff, K. J., Nord, K. M., Lu, Y., Cannell, B., Weitlauf, J. C. 2021: 106480


    BACKGROUND: Exposure to ultraviolet radiation (UVR) is the major modifiable risk factor for skin cancers. The majority of lifetime UVR exposure occurs before age 20, underscoring an important window for risk reduction. Incorporation of skills-based sunscreen education into school health curricula may foster the development of consistent and effective use of sunscreen among children and youth. We describe the study protocol for a first-of-its-kind study that examined the feasibility of bringing skills-based sunscreen education into kindergarten classrooms.METHODS: Participants were 96 kindergarten students across four classrooms in a single elementary school. A single-blind open-label trial design was used to evaluate the feasibility of incorporating a song-based, video-guided intervention for independent application of sunscreen into the kindergarten curriculum. Students first completed a 10-day no-intervention baseline period, followed by a 10-day intervention period, and then a 10-day randomized follow-up period where students were randomly assigned to continue with the intervention or to revert to the no-intervention condition.OUTCOMES: Feasibility metrics associated with study process, resources, management, scientific outcomes and safety were gathered. The primary outcome was pre-to-post intervention changes in student engagement in the sunscreen task. The secondary outcome was pre-to-post intervention changes in the proportion of exposed skin to which a student applies sunscreen. Teacher and student perceptions of intervention value and utility were also evaluated.DISCUSSION: This is the study protocol for a clinical trial designed to determine the feasibility of implementing a skills-based sunscreen curriculum in kindergarten classrooms. Next steps include evaluation of the intervention for efficacy and effectiveness.CLINICAL TRIAL REGISTRATION: NCT03752736.

    View details for DOI 10.1016/j.cct.2021.106480

    View details for PubMedID 34126263

  • Prrx1 Fibroblasts Represent a Pro-fibrotic Lineage in the Mouse Ventral Dermis. Cell reports Leavitt, T., Hu, M. S., Borrelli, M. R., Januszyk, M., Garcia, J. T., Ransom, R. C., Mascharak, S., desJardins-Park, H. E., Litzenburger, U. M., Walmsley, G. G., Marshall, C. D., Moore, A. L., Duoto, B., Adem, S., Foster, D. S., Salhotra, A., Shen, A. H., Griffin, M., Shen, E. Z., Barnes, L. A., Zielins, E. R., Maan, Z. N., Wei, Y., Chan, C. K., Wan, D. C., Lorenz, H. P., Chang, H. Y., Gurtner, G. C., Longaker, M. T. 2020; 33 (6): 108356


    Fibroblast heterogeneity has been shown within the unwounded mouse dorsal dermis, with fibroblast subpopulations being identified according to anatomical location and embryonic lineage. Using lineage tracing, we demonstrate that paired related homeobox 1 (Prrx1)-expressing fibroblasts are responsible for acute and chronic fibroses in the ventral dermis. Single-cell transcriptomics further corroborated the inherent fibrotic characteristics of Prrx1 fibroblasts during wound repair. In summary, we identify and characterize a fibroblast subpopulation in the mouse ventral dermis with intrinsic scar-forming potential.

    View details for DOI 10.1016/j.celrep.2020.108356

    View details for PubMedID 33176144

  • Doxycycline Reduces Scar Thickness and Improves Collagen Architecture ANNALS OF SURGERY Moore, A. L., desJardins-Park, H. E., Duoto, B. A., Mascharak, S., Murphy, M. P., Irizarry, D. M., Foster, D. S., Jones, R. E., Barnes, L. A., Marshall, C. D., Ransom, R. C., Wernig, G., Longaker, M. T. 2020; 272 (1): 183–93
  • Sex and Racial/Ethnic Diversity of US Medical Students and Their Exposure to Dermatology Programs JAMA DERMATOLOGY Barnes, L. A., Bae, G. H., Nambudiri, V. E. 2019; 155 (4): 490–91
  • Lessons learned from the development of a hidradenitis suppurativa xenograft mouse model. Clinical and experimental dermatology Quartey, Q. Q., Miller, R. J., Pinsker, B. L., Okoh, U. J., Shipman, W. D., George, B. A., Nwizu, C. C., Barnes, L. A., Kerns, M. L., Caffrey, J. A., Aliu, O. n., Brown, I. D., Succaria, F. n., Maynard, J. P., Herbert, A. S., Kang, S. n., Miller, L. S., Okoye, G. A., Byrd, A. S. 2019


    Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease originating from the pilosebaceous unit in which patients develop painful abscesses, sinus tracts, nodules, and scarring typically in intertriginous areas. Major gaps in our understanding of HS exist and may be partially due to the lack of an animal model for experimental studies. Here, we developed an HS xenograft mouse model using human HS lesions grafted onto immunocompromised mice. Although the model had its limitations, several informative lessons were learned that may contribute to future attempts at an HS animal model. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/ced.14054

    View details for PubMedID 31322280

  • Mechanical Forces in Cutaneous Wound Healing: Emerging Therapies to Minimize Scar Formation ADVANCES IN WOUND CARE Barnes, L. A., Marshall, C. D., Leavitt, T., Hu, M. S., Moore, A. L., Gonzalez, J. G., Longaker, M. T., Gurtner, G. C. 2018; 7 (2): 47–56


    Significance: Excessive scarring is major clinical and financial burden in the United States. Improved therapies are necessary to reduce scarring, especially in patients affected by hypertrophic and keloid scars. Recent Advances: Advances in our understanding of mechanical forces in the wound environment enable us to target mechanical forces to minimize scar formation. Fetal wounds experience much lower resting stress when compared with adult wounds, and they heal without scars. Therapies that modulate mechanical forces in the wound environment are able to reduce scar size. Critical Issues: Increased mechanical stresses in the wound environment induce hypertrophic scarring via activation of mechanotransduction pathways. Mechanical stimulation modulates integrin, Wingless-type, protein kinase B, and focal adhesion kinase, resulting in cell proliferation and, ultimately, fibrosis. Therefore, the development of therapies that reduce mechanical forces in the wound environment would decrease the risk of developing excessive scars. Future Directions: The development of novel mechanotherapies is necessary to minimize scar formation and advance adult wound healing toward the scarless ideal. Mechanotransduction pathways are potential targets to reduce excessive scar formation, and thus, continued studies on therapies that utilize mechanical offloading and mechanomodulation are needed.

    View details for PubMedID 29392093

    View details for PubMedCentralID PMC5792236

  • Delivery of monocyte lineage cells in a biomimetic scaffold enhances tissue repair. JCI insight Hu, M. S., Walmsley, G. G., Barnes, L. A., Weiskopf, K. n., Rennert, R. C., Duscher, D. n., Januszyk, M. n., Maan, Z. N., Hong, W. X., Cheung, A. T., Leavitt, T. n., Marshall, C. D., Ransom, R. C., Malhotra, S. n., Moore, A. L., Rajadas, J. n., Lorenz, H. P., Weissman, I. L., Gurtner, G. C., Longaker, M. T. 2017; 2 (19)


    The monocyte lineage is essential to normal wound healing. Macrophage inhibition or knockout in mice results in impaired wound healing through reduced neovascularization, granulation tissue formation, and reepithelialization. Numerous studies have either depleted macrophages or reduced their activity in the context of wound healing. Here, we demonstrate that by increasing the number of macrophages or monocytes in the wound site above physiologic levels via pullulan-collagen composite dermal hydrogel scaffold delivery, the rate of wound healing can be significantly accelerated in both wild-type and diabetic mice, with no adverse effect on the quality of repair. Macrophages transplanted onto wounds differentiate into M1 and M2 phenotypes of different proportions at various time points, ultimately increasing angiogenesis. Given that monocytes can be readily isolated from peripheral blood without in vitro manipulation, these findings hold promise for translational medicine aimed at accelerating wound healing across a broad spectrum of diseases.

    View details for PubMedID 28978794

  • Assessment of correctness, content omission, and risk of harm in large language model responses to dermatology continuing medical education questions. The Journal of investigative dermatology Cai, Z. R., Chen, M. L., Kim, J., Novoa, R. A., Barnes, L. A., Beam, A., Linos, E. 2024

    View details for DOI 10.1016/j.jid.2024.01.015

    View details for PubMedID 38310972

  • Disease Complications Hidradenitis Suppurativa Patient Guide Gomez, J., Barnes, L., Aleshin, M. 2023
  • Friend or foe: Elevated sera levels of IgM autoantibodies targeting hair follicle components detected in patients with Hidradenitis Suppurativa Kerns, M. L., Carmona-Rivera, C., Zhu, C., Li, Q., Shipman, W. D., Barnes, L. A., Kaplan, M. J., Okoye, G. A., Byrd, A. S. ELSEVIER SCIENCE INC. 2020: S99
  • Specimen Collection for Translational Studies in Hidradenitis Suppurativa. Scientific reports Byrd, A. S., Dina, Y., Okoh, U. J., Quartey, Q. Q., Carmona-Rivera, C., Williams, D. W., Kerns, M. L., Miller, R. J., Petukhova, L., Naik, H. B., Barnes, L. A., Shipman, W. D., Caffrey, J. A., Sacks, J. M., Milner, S. M., Aliu, O., Broderick, K. P., Kim, D., Liu, H., Dillen, C. A., Ahn, R., Frew, J. W., Kaplan, M. J., Kang, S., Garza, L. A., Miller, L. S., Alavi, A., Lowes, M. A., Okoye, G. A. 2019; 9 (1): 12207


    Hidradenitis suppurativa (HS) is a chronic inflammatory disorder characterized by painful nodules, sinus tracts, and scars occurring predominantly in intertriginous regions. The prevalence of HS is currently 0.053-4%, with a predominance in African-American women and has been linked to low socioeconomic status. The majority of the reported literature is  retrospective, population based, epidemiologic studies. In this regard, there is a need to establish a repository of biospecimens, which represent appropriate gender and racial demographics amongst HS patients. These efforts will diminish knowledge gaps in understanding the disease pathophysiology. Hence, we sought to outline a step-by-step protocol detailing how we established our HS biobank to facilitate the formation of other HS tissue banks. Equipping researchers with carefully detailed processes for collection of HS specimens would accelerate the accumulation of well-organized human biological material. Over time, the scientific community will have access to a broad range of HS tissue biospecimens, ultimately leading to more rigorous basic and translational research. Moreover, an improved understanding of the pathophysiology is necessary for the discovery of novel therapies for this debilitating disease. We aim to provide high impact translational research methodology for cutaneous biology research and foster multidisciplinary collaboration and advancement of our understanding of cutaneous diseases.

    View details for DOI 10.1038/s41598-019-48226-w

    View details for PubMedID 31434914

    View details for PubMedCentralID PMC6704132

  • Sarcopenia Is a Risk Factor for Infection for Patients Undergoing Abdominoperineal Resection and Flap-based Reconstruction. Plastic and reconstructive surgery. Global open Miller, T. J., Sheckter, C. C., Barnes, L. A., Li, A. Y., Momeni, A. 2019; 7 (7): e2343


    Abdominoperineal resection (APR) carries a high risk of morbidity. Preoperative risk assessment can help with patient counseling, minimize adverse outcomes, and guide surgeons in their choice of reconstruction. This study examined the impact of sarcopenia (low lean muscle mass) on postoperative complications after APR.One hundred seventy-eight patients who underwent APR between May 2000 and July 2017 were retrospectively analyzed. Sarcopenia was identified on preoperative computed tomography scans using the Hounsfield Unit Average Calculation. Two cohorts were compared (group 1: primary perineal closure; group 2: flap-based perineal reconstruction). Multivariable analysis evaluated predictors of complications.Sarcopenia was an independent risk factor for postoperative surgical site infection in patients undergoing APR (odds ratio [OR] = 2.9, P = 0.04). The risk for sarcopenic patients who underwent flap-based perineal reconstruction was even higher (OR = 8.9, P < 0.01). Male sex was also found to be a risk factor for infection (OR = 3.5, P < 0.01). Perineal flap-based reconstruction was a risk factor for delayed wound healing (OR = 3.2, P < 0.01).Sarcopenia was an independent risk factor for infection in patients undergoing APR. This risk was even greater in patients undergoing flap-based perineal reconstruction. Sarcopenia can be identified on preoperative imaging and inform surgeons on risk stratification and surgical plan.

    View details for DOI 10.1097/GOX.0000000000002343

    View details for PubMedID 31942365

    View details for PubMedCentralID PMC6952152

  • Doxycycline Reduces Scar Thickness and Improves Collagen Architecture. Annals of surgery Moore, A. L., desJardins-Park, H. E., Duoto, B. A., Mascharak, S., Murphy, M. P., Irizarry, D. M., Foster, D. S., Jones, R. E., Barnes, L. A., Marshall, C. D., Ransom, R. C., Wernig, G., Longaker, M. T. 2018


    OBJECTIVE: To investigate the effects of local doxycycline administration on skin scarring.BACKGROUND: Skin scarring represents a major source of morbidity for surgical patients. Doxycycline, a tetracycline antibiotic with off-target effects on the extracellular matrix, has demonstrated antifibrotic effects in multiple organs. However, doxycycline's potential effects on skin scarring have not been explored in vivo.METHODS: Female C57BL/6J mice underwent dorsal wounding following an established splinted excisional skin wounding model. Doxycycline was administered by local injection into the wound base following injury. Wounds were harvested upon complete wound closure (postoperative day 15) for histological examination and biomechanical testing of scar tissue.RESULTS: A one-time dose of 3.90 mM doxycycline (2 mg/mL) within 12 hours of injury was found to significantly reduce scar thickness by 24.8% (P < 0.0001) without compromising tensile strength. The same effect could not be achieved by oral dosing. In doxycycline-treated scar matrices, collagen I content was significantly reduced (P = 0.0317) and fibers were favorably arranged with significantly increased fiber randomness (P = 0.0115). Common culprits of altered wound healing mechanics, including angiogenesis and inflammation, were not impacted by doxycycline treatment. However, engrailed1 profibrotic fibroblasts, responsible for scar extracellular matrix deposition, were significantly reduced with doxycycline treatment (P = 0.0005).CONCLUSIONS: Due to the substantial improvement in skin scarring and well-established clinical safety profile, locally administered doxycycline represents a promising vulnerary agent. As such, we favor rapid translation to human patients as an antiscarring therapy.

    View details for PubMedID 30585822

  • Pachydermodactyly: Case report including clinical and histopathologic diagnostic pitfalls JOURNAL OF CUTANEOUS PATHOLOGY Barnes, L. A., Bae, G. H., Lewis, M. A., Rieger, K. E. 2018; 45 (12): 949–53

    View details for DOI 10.1111/cup.13359

    View details for Web of Science ID 000450005800014

  • Engrailed1-Positive Fibroblasts May Modulate Transcription of the TGF-beta Pathway in the Transition from Scarless Healing to Scarring Phenotype Moore, A. L., Marshall, C. D., Des Jardins-Park, H. E., Duoto, B. A., Mascharak, S., Barnes, A., Ransom, R. C., Hu, M. S., Lorenz, H., Longaker, M. T. ELSEVIER SCIENCE INC. 2018: E221–E222
  • Acta2, Tnc, and Col24a1 Expression Are Associated with Abdominal Adhesion Formation Marshall, C. D., Foster, D. S., Ransom, R. C., Manjunath, A., Gulati, G., Hu, M. S., Moore, A. L., Barnes, L. A., Longaker, M. T. ELSEVIER SCIENCE INC. 2018: E128
  • Pachydermodactyly: case report including clinical and histopathologic diagnostic pitfalls. Journal of cutaneous pathology Barnes, L. A., Bae, G. H., Lewis, M. A., Rieger, K. E. 2018


    Pachydermodactyly is a rare, benign condition characterized by swelling and thickening of the periarticular skin, most commonly at the proximal interphalangeal joints. Diagnosis is routinely made through correlation of clinical, histopathologic, and radiographic findings. Here we report a case of pachydermodactyly in a 25 year-old male, with emphasis on the clinical and histopathologic differential diagnosis and potential diagnostic pitfalls. This article is protected by copyright. All rights reserved.

    View details for PubMedID 30221379

  • Determining the impact of sarcopenia on postoperative complications after ventral hernia repair. Journal of plastic, reconstructive & aesthetic surgery : JPRAS Barnes, L. A., Li, A. Y., Wan, D. C., Momeni, A. 2018; 71 (9): 1260–68


    BACKGROUND: Postoperative complication following ventral hernia repair (VHR) is a major clinical and financial burden. Preoperative risk assessment is necessary to minimize adverse outcomes following VHR. This study examines the ability of an independent parameter to predict postoperative morbidity following VHR.METHODS: A retrospective analysis of 58 patients who underwent VHR by component separation between January 2009 and December 2013 was performed. Preoperative abdominal CT scans were analyzed to assess sarcopenia. Sarcopenia was determined using the Hounsfield unit average calculation (HUAC), a measure of psoas muscle size and density. Sarcopenia was defined as an HUAC score of less than 19.6HU calculated using receiver operating characteristic (ROC) analysis and the Youden index. Multivariate analysis was performed to analyze the association of sarcopenia and postoperative complications.RESULTS: Preoperative sarcopenia was associated with an increased risk for postoperative complications (odds ratio [OR] = 5.3; p = 0.04). Preexisting gastrointestinal conditions such as ulcerative colitis or colon cancer were associated with an increased risk for postoperative complications (OR = 5.7; p = 0.05). A significantly higher rate of hernia recurrence (33.3% vs. 10.8% [p = 0.04]) and renal failure (19% vs. 2.7% [p = 0.03]) was noted in patients with sarcopenia when compared to patients without sarcopenia.CONCLUSIONS: Sarcopenia is an independent risk factor for postoperative complications in patients who underwent VHR. Assessment of sarcopenia using the HUAC score provides an opportunity for the adjustment of perioperative care plans to minimize postoperative complication rates.

    View details for PubMedID 30173713

  • Determining the impact of sarcopenia on postoperative complications after ventral hernia repair JOURNAL OF PLASTIC RECONSTRUCTIVE AND AESTHETIC SURGERY Barnes, L. A., Li, A. Y., Wan, D. C., Momeni, A. 2018; 71 (9): 1260–68
  • Cutaneous Scarring: Basic Science, Current Treatments, and Future Directions ADVANCES IN WOUND CARE Marshall, C. D., Hu, M. S., Leavitt, T., Barnes, L. A., Lorenz, H., Longaker, M. T. 2018; 7 (2): 29–45


    Significance: Scarring of the skin from burns, surgery, and injury constitutes a major burden on the healthcare system. Patients affected by major scars, particularly children, suffer from long-term functional and psychological problems. Recent Advances: Scarring in humans is the end result of the wound healing process, which has evolved to rapidly repair injuries. Wound healing and scar formation are well described on the cellular and molecular levels, but truly effective molecular or cell-based antiscarring treatments still do not exist. Recent discoveries have clarified the role of skin stem cells and fibroblasts in the regeneration of injuries and formation of scar. Critical Issues: It will be important to show that new advances in the stem cell and fibroblast biology of scarring can be translated into therapies that prevent and reduce scarring in humans without major side effects. Future Directions: Novel therapies involving the use of purified human cells as well as agents that target specific cells and modulate the immune response to injury are currently undergoing testing. In the basic science realm, researchers continue to refine our understanding of the role that particular cell types play in the development of scar.

    View details for PubMedID 29392092

    View details for PubMedCentralID PMC5792238

  • Scarless wound healing: Transitioning from fetal research to regenerative healing. Wiley interdisciplinary reviews. Developmental biology Moore, A. L., Marshall, C. D., Barnes, L. A., Murphy, M. P., Ransom, R. C., Longaker, M. T. 2018; 7 (2)


    Since the discovery of scarless fetal skin wound healing, research in the field has expanded significantly with the hopes of advancing the finding to adult human patients. There are several differences between fetal and adult skin that have been exploited to facilitate scarless healing in adults including growth factors, cytokines, and extracellular matrix substitutes. However, no one therapy, pathway, or cell subtype is sufficient to support scarless wound healing in adult skin. More recently, products that contain or mimic fetal and adult uninjured dermis were introduced to the wound healing market with promising clinical outcomes. Through our review of the major experimental targets of fetal wound healing, we hope to encourage research in areas that may have a significant clinical impact. Additionally, we will investigate therapies currently in clinical use and evaluate whether they represent a legitimate advance in regenerative medicine or a vulnerary agent. WIREs Dev Biol 2018, 7:e309. doi: 10.1002/wdev.309 This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Regeneration Plant Development > Cell Growth and Differentiation Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells.

    View details for PubMedID 29316315

  • Analysis of Scar Forming Fibroblasts Reveals Distinct Changes in Epigenetic Accessibility During Times of Phenotypic Transition Plast Reconstr Surg Glob Open Moore, A., Litzenburger, U., Marshall, C., et al 2018
  • Beyond Antibiotics: Local Doxycycline Administration Reduces Scarring and Improves Wound Healing by Modulating Scarring Fibroblast Behavior Plast Reconstr Surg Glob Open Des Jardins-Park, H. E., Moore, A. L., Murphy, M. P., et al 2018
  • Cellular Mechanisms Underlying Regeneration in Mandibular Distraction Osteogenesis Ransom, R. C., Leavitt, T., Murphy, M. P., Marecic, O., Lopez, M., Marshall, C. D., Barnes, L. A., Wan, D. C., Chan, C. K., Longaker, M. T. ELSEVIER SCIENCE INC. 2017: E143–E144
  • Sanativo Wound Healing Product Does Not Accelerate Reepithelialization in a Mouse Cutaneous Wound Healing Model. Plastic and reconstructive surgery Marshall, C. D., Hu, M. S., Leavitt, T., Barnes, L. A., Cheung, A. T., Malhotra, S., Lorenz, H. P., Delp, S. L., Quake, S. R., Longaker, M. T. 2017; 139 (2): 343-352


    Sanativo is an over-the-counter Brazilian product derived from Amazon rainforest plant extract that is purported to improve the healing of skin wounds. Two experimental studies have shown accelerated closure of nonsplinted excisional wounds in rat models. However, these models allow for significant contraction of the wound and do not approximate healing in the tight skin of humans.Full-thickness excisional wounds were created on the dorsal skin of mice and were splinted with silicone rings, a model that forces the wound to heal by granulation and reepithelialization. Sanativo or a control solution was applied either daily or every other day to the wounds. Photographs were taken every other day, and the degree of reepithelialization of the wounds was determined.With both daily and every-other-day applications, Sanativo delayed reepithelialization of the wounds. Average time to complete healing was faster with control solution versus Sanativo in the daily application group (9.4 versus 15.2 days; p < 0.0001) and the every-other-day application group (11 versus 13 days; p = 0.017). The size of visible scar at the last time point of the study was not significantly different between the groups, and no differences were found on histologic examination.Sanativo wound healing compound delayed wound reepithelialization in a mouse splinted excisional wound model that approximates human wound healing. The size of visible scar after complete healing was not improved with the application of Sanativo. These results should cast doubt on claims that this product can improve wound healing in humans.

    View details for DOI 10.1097/PRS.0000000000003013

    View details for PubMedID 28121865

  • Rapid Isolation of BMPR-IB plus Adipose-Derived Stromal Cells for Use in a Calvarial Defect Healing Model JOVE-JOURNAL OF VISUALIZED EXPERIMENTS Marshall, C. D., Zielins, E. R., Brett, E. A., Blackshear, C. P., Hu, M. S., Leavitt, T., Barnes, L. A., Lorenz, H. P., Longaker, M. T., Wan, D. C. 2017


    Invasive cancers, major injuries, and infection can cause bone defects that are too large to be reconstructed with preexisting bone from the patient's own body. The ability to grow bone de novo using a patient's own cells would allow bony defects to be filled with adequate tissue without the morbidity of harvesting native bone. There is interest in the use of adipose-derived stromal cells (ASCs) as a source for tissue engineering because these are obtained from an abundant source: the patient's own adipose tissue. However, ASCs are a heterogeneous population and some subpopulations may be more effective in this application than others. Isolation of the most osteogenic population of ASCs could improve the efficiency and effectiveness of a bone engineering process. In this protocol, ASCs are obtained from subcutaneous fat tissue from a human donor. The subpopulation of ASCs expressing the marker BMPR-IB is isolated using FACS. These cells are then applied to an in vivo calvarial defect healing assay and are found to have improved osteogenic regenerative potential compared with unsorted cells.

    View details for DOI 10.3791/55120

    View details for Web of Science ID 000397847700048

    View details for PubMedID 28287559

  • Excess Dermal Tissue Remodeling In Vivo: Does It Settle? Plastic and reconstructive surgery Leavitt, T., Hu, M. S., Zielins, E. R., Barnes, L. A., Marshall, C. D., Wan, D. C., Lorenz, H. P., Gurtner, G. C., Longaker, M. T. 2017; 139 (2): 415e-424e


    Surgical manipulation of skin may result in undesired puckering of excess tissue, which is generally assumed to settle over time. In this article, the authors address the novel question of how this excess tissue remodels.Purse-string sutures (6-0 nylon) were placed at the midline dorsum of 22 wild-type BALB/c mice in a circular pattern marked with tattoo ink. Sutures were cinched and tied under tension in the treatment group, creating an excess tissue deformity, whereas control group sutures were tied without tension. After 2 or 4 weeks, sutures were removed. The area of tattooed skin was measured up to 56 days after suture removal. Histologic analysis was performed on samples harvested 14 days after suture removal.The majority of excess tissue deformities flattened within 2 days after suture removal. However, the sutured skin in the treatment group decreased in area by an average of 18 percent from baseline (n = 9), compared to a 1 percent increase in the control group (n = 10) at 14 days after suture removal (p < 0.05). This was similarly observed at 28 days (treatment, -11.7 percent; control, 4.5 percent; n = 5; p = 0.0243). Despite flattening, deformation with purse-string suture correlated with increased collagen content of skin, in addition to increased numbers of myofibroblasts. Change in area did not correlate with duration of suture placement.Excess dermal tissue deformities demonstrate the ability to remodel with gross flattening of the skin, increased collagen deposition, and incomplete reexpansion to baseline area. Further studies will reveal whether our findings in this mouse model translate to humans.

    View details for DOI 10.1097/PRS.0000000000003026

    View details for PubMedID 28121870

  • A Mouse Model of Mandibular Distraction Osteogenesis Plastic and Reconstructive Surgery Ransom, R. C., Leavitt, T., Barnes, L. A., et al 2017
  • Intestinal Smooth Muscle Cell Migration May Contribute to Abdominal Adhesion Formation Marshall, C. D., Hu, M. S., Leavitt, T., Ransom, R. C., Barnes, L. A., Lorenz, H., Longaker, M. T. ELSEVIER SCIENCE INC. 2016: E106–E107
  • Scarless wound healing: finding the right cells and signals. Cell and tissue research Leavitt, T., Hu, M. S., Marshall, C. D., Barnes, L. A., Lorenz, H. P., Longaker, M. T. 2016; 365 (3): 483-493


    From the moment we are born, every injury to the skin has the potential to form a scar, many of which can impair form and/or function. As such, scar management constitutes a billion-dollar industry. However, effectively promoting scarless wound healing remains an elusive goal. The complex interactions of wound healing contribute to our inability to recapitulate scarless wound repair as it occurs in nature, such as in fetal skin and the oral mucosa. However, many new advances have occurred in recent years, some of which have translated scientific findings from bench to bedside. In vivo lineage tracing has helped establish a variety of novel cellular culprits that may act as key drivers of the fibrotic response. These newly characterized cell populations present further targets for therapeutic intervention, some of which have previously demonstrated promising results in animal models. Here, we discuss several recent studies that identify exciting approaches for diminishing scar formation. Particular attention will also be paid to the canonical Wnt/β-catenin signaling pathway, which plays an important role in both embryogenesis and tissue repair. New insights into the differential effects of Wnt signaling on heterogeneous fibroblast and keratinocyte populations within the skin further demonstrate methods by which wound healing can be re-directed to a more fetal scarless phenotype. Graphical abstract Recent approaches to reducing scar formation. Representation showing novel scientific approaches for decreasing scar formation, including the targeting of pro-fibrotic cell populations based on surface molecule expression (e.g. DPP4(+) fibroblasts, ADAM12(+) pericytes). Modulation of cellular mechanotransduction pathways are another means to reduce scar formation, both at the molecular level or, macroscopically with dressings designed to offload tension, at cutaneous wound sites (ADAM12 a disintegrin and metalloprotease 12, DPP4 dipeptidyl peptidase-4, FAK focal adhesion kinase).

    View details for DOI 10.1007/s00441-016-2424-8

    View details for PubMedID 27256396

    View details for PubMedCentralID PMC5010960

  • Creation of Abdominal Adhesions in Mice JOVE-JOURNAL OF VISUALIZED EXPERIMENTS Marshall, C. D., Hu, M. S., Leavitt, T., Barnes, L. A., Cheung, A. T., Malhotra, S., Lorenz, H. P., Longaker, M. T. 2016


    Abdominal adhesions consist of fibrotic tissue that forms in the peritoneal space in response to an inflammatory insult, typically surgery or intraabdominal infection. The precise mechanisms underlying adhesion formation are poorly understood. Many compounds and physical barriers have been tested for their ability to prevent adhesions after surgery with varying levels of success. The mouse and rat are important models for the study of abdominal adhesions. Several different techniques for the creation of adhesions in the mouse and rat exist in the literature. Here we describe a protocol utilizing abrasion of the cecum with sandpaper and sutures placed in the right abdominal sidewall. The mouse is anesthetized and the abdomen is prepped. A midline laparotomy is created and the cecum is identified. Sandpaper is used to gently abrade the surface of the cecum. Next, several figure-of-eight sutures are placed into the peritoneum of the right abdominal sidewall. The abdominal cavity is irrigated, a small amount of starch is applied, and the incision is closed. We have found that this technique produces the most consistent adhesions with the lowest mortality rate.

    View details for DOI 10.3791/54450

    View details for Web of Science ID 000391742700091

    View details for PubMedID 27685681

  • SANATIVO WORSENS MURINE SKIN WOUND HEALING Marshall, C. D., Hu, M. S., Leavitt, T., Barnes, L. A., Longaker, M. T. WILEY-BLACKWELL. 2016: A17
  • ACTIVATION OF HIF BY SMALL MOLECULE INHIBITORS OF PHD2 IMPROVES HEALING OF CUTANEOUS WOUNDS AND CALVARIAL DEFECTS Hu, M. S., Barnes, L. A., Hong, W., Xie, M., Tang, S., Rennert, R. C., Gurtner, G. C., Giaccia, A. J., Lorenz, H. P., Ding, S., Longaker, M. T. WILEY-BLACKWELL. 2016: A11
  • IN VIVO REMODELING OF EXCESS TISSUE DEFORMITIES FOLLOWING PROLONGED MECHANICAL DEFORMATION Leavitt, T., Hu, M. S., Barnes, L. A., Zielins, E. R., Marshall, C. D., Wan, D. C., Gurtner, G. C., Lorenz, H., Longaker, M. T. WILEY-BLACKWELL. 2016: A15
  • Stem cells and chronic wound healing: state of the art CHRONIC WOUND CARE MANAGEMENT AND RESEARCH Leavitt, T., Hu, M. S., Marshall, C. D., Barnes, L. A., Longaker, M. T., Lorenz, H. 2016; 3: 7–27
  • Activation of HIF by Small Molecule Inhibitors ofPhd2 Improves Healing of Cutaneous Wounds and Calvarial Defects Plastic and Reconstructive Surgery Hu, M. S., Barnes, L. A., Hong, W., et al 2016
  • Generation of a Novel Scaffold for In Vivo Polarization of Therapeutic Macrophages and Delivery of IL-10 to Improve Cutaneous Wound Healing Plast Reconstr Surg Barnes, L. A., Hu, M. S., Cheung, A. T., et al 2016
  • Effects of multidisciplinary prenatal care and delivery mode on gastroschisis outcomes JOURNAL OF PEDIATRIC SURGERY Synder, C. W., Biggio, J. R., Brinson, P., Barnes, L. A., Bartle, D. T., Georgeson, K. E., Muensterer, O. J. 2011; 46 (1): 86-89


    This study examined the effects of multidisciplinary prenatal care and delivery mode on gastroschisis outcomes, with adjustment for key confounding variables.This retrospective cohort study included all gastroschisis patients treated at a single tertiary children's hospital between 1999 and 2009. Prenatal care, delivery mode (vaginal vs cesarean section before labor vs after labor), patient characteristics, and clinical outcomes were determined by chart review. Time to discontinuation of parenteral nutrition (PN) was the primary outcome of interest. Effects of multidisciplinary prenatal care and delivery mode were evaluated using Cox proportional hazards regression models that included gestational age, birth weight, sex, concomitant intestinal complications, and year of admission.Of 167 patients included, 46% were delivered vaginally, 69% received multidisciplinary prenatal care, and median time to PN discontinuation was 38 days. On multivariable modeling, gestational age, uncomplicated gastroschisis, and year of admission were significant predictors of early PN independence. Delivery mode and prenatal care had no independent effect on outcomes, although patients receiving multidisciplinary prenatal care were more likely to be born at term (49% vs 27%, P = .01).Gestational age and intestinal complications are the major determinants of outcome in gastroschisis. Multidisciplinary prenatal care may facilitate term delivery.

    View details for DOI 10.1016/j.jpedsurg.2010.09.067

    View details for Web of Science ID 000286194200024

    View details for PubMedID 21238646