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1.
J Cell Mol Med ; 28(8): e18306, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38613357

ABSTRACT

Topical patch delivery of deferoxamine (DFO) has been studied as a treatment for this fibrotic transformation in irradiated tissue. Efficacy of a novel cream formulation of DFO was studied as a RIF therapeutic in unwounded and excisionally wounded irradiated skin. C57BL/6J mice underwent 30 Gy of radiation to the dorsum followed by 4 weeks of recovery. In a first experiment, mice were separated into six conditions: DFO 50 mg cream (D50), DFO 100 mg cream (D100), soluble DFO injections (DI), DFO 1 mg patch (DP), control cream (Vehicle), and irradiated untreated skin (IR). In a second experiment, excisional wounds were created on the irradiated dorsum of mice and then divided into four treatment groups: DFO 100 mg Cream (W-D100), DFO 1 mg patch (W-DP), control cream (W-Vehicle), and irradiated untreated wounds (W-IR). Laser Doppler perfusion scans, biomechanical testing, and histological analysis were performed. In irradiated skin, D100 improved perfusion compared to D50 or DP. Both D100 and DP enhanced dermal characteristics, including thickness, collagen density and 8-isoprostane staining compared to untreated irradiated skin. D100 outperformed DP in CD31 staining, indicating higher vascular density. Extracellular matrix features of D100 and DP resembled normal skin more closely than DI or control. In radiated excisional wounds, D100 facilitated faster wound healing and increased perfusion compared to DP. The 100 mg DFO cream formulation rescued RIF of unwounded irradiated skin and improved excisional wound healing in murine skin relative to patch delivery of DFO.


Subject(s)
Deferoxamine , Radiation Fibrosis Syndrome , Mice , Animals , Mice, Inbred C57BL , Deferoxamine/pharmacology , Deferoxamine/therapeutic use , Skin , Perfusion
2.
J Reconstr Microsurg ; 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38382637

ABSTRACT

BACKGROUND: With the growing relevance of artificial intelligence (AI)-based patient-facing information, microsurgical-specific online information provided by professional organizations was compared with that of ChatGPT (Chat Generative Pre-Trained Transformer) and assessed for accuracy, comprehensiveness, clarity, and readability. METHODS: Six plastic and reconstructive surgeons blindly assessed responses to 10 microsurgery-related medical questions written either by the American Society of Reconstructive Microsurgery (ASRM) or ChatGPT based on accuracy, comprehensiveness, and clarity. Surgeons were asked to choose which source provided the overall highest-quality microsurgical patient-facing information. Additionally, 30 individuals with no medical background (ages: 18-81, µ = 49.8) were asked to determine a preference when blindly comparing materials. Readability scores were calculated, and all numerical scores were analyzed using the following six reliability formulas: Flesch-Kincaid Grade Level, Flesch-Kincaid Readability Ease, Gunning Fog Index, Simple Measure of Gobbledygook Index, Coleman-Liau Index, Linsear Write Formula, and Automated Readability Index. Statistical analysis of microsurgical-specific online sources was conducted utilizing paired t-tests. RESULTS: Statistically significant differences in comprehensiveness and clarity were seen in favor of ChatGPT. Surgeons, 70.7% of the time, blindly choose ChatGPT as the source that overall provided the highest-quality microsurgical patient-facing information. Nonmedical individuals 55.9% of the time selected AI-generated microsurgical materials as well. Neither ChatGPT nor ASRM-generated materials were found to contain inaccuracies. Readability scores for both ChatGPT and ASRM materials were found to exceed recommended levels for patient proficiency across six readability formulas, with AI-based material scored as more complex. CONCLUSION: AI-generated patient-facing materials were preferred by surgeons in terms of comprehensiveness and clarity when blindly compared with online material provided by ASRM. Studied AI-generated material was not found to contain inaccuracies. Additionally, surgeons and nonmedical individuals consistently indicated an overall preference for AI-generated material. A readability analysis suggested that both materials sourced from ChatGPT and ASRM surpassed recommended reading levels across six readability scores.

3.
Plast Reconstr Surg ; 153(1): 121-128, 2024 01 01.
Article in English | MEDLINE | ID: mdl-36988644

ABSTRACT

BACKGROUND: A significant gap exists in the translatability of small-animal models to human subjects. One important factor is poor laboratory models involving human tissue. Thus, the authors have created a viable postnatal human skin xenograft model using athymic mice. METHODS: Discarded human foreskins were collected following circumcision. All subcutaneous tissue was removed from these samples sterilely. Host CD-1 nude mice were then anesthetized, and dorsal skin was sterilized. A 1.2-cm-diameter, full-thickness section of dorsal skin was excised. The foreskin sample was then placed into the full-thickness defect in the host mice and sutured into place. Xenografts underwent dermal wounding using a 4-mm punch biopsy after engraftment. Xenografts were monitored for 14 days after wounding and then harvested. RESULTS: At 14 days postoperatively, all mice survived the procedure. Grossly, the xenograft wounds showed formation of a human scar at postoperative day 14. Hematoxylin and eosin and Masson trichome staining confirmed scar formation in the wounded human skin. Using a novel artificial intelligence algorithm using picrosirius red staining, scar formation was confirmed in human wounded skin compared with the unwounded skin. Histologically, CD31 + immunostaining confirmed vascularization of the xenograft. The xenograft exclusively showed human collagen type I, CD26 + , and human nuclear antigen in the human scar without any staining of these human markers in the murine skin. CONCLUSION: The proposed model demonstrates wound healing to be a local response from tissue resident human fibroblasts and allows for reproducible evaluation of human skin wound repair in a preclinical model. CLINICAL RELEVANCE STATEMENT: Radiation-induced fibrosis is a widely prevalent clinical phenomenon without a well-defined treatment at this time. This study will help establish a small-animal model to better understand and develop novel therapeutics to treat irradiated human skin.


Subject(s)
Cicatrix , Skin , Wound Healing , Animals , Humans , Male , Mice , Artificial Intelligence , Cicatrix/pathology , Disease Models, Animal , Heterografts , Mice, Nude , Skin/pathology , Wound Healing/physiology
4.
Wound Repair Regen ; 31(1): 77-86, 2023 01.
Article in English | MEDLINE | ID: mdl-36484112

ABSTRACT

Wound dehiscence, oftentimes a result of the poor tensile strength of early healing wounds, is a significant threat to the post-operative patient, potentially causing life-threatening complications. Vanadate, a protein tyrosine phosphatase inhibitor, has been shown to alter the organisation of deposited collagen in healing wounds and significantly improve the tensile strength of incisional wounds in rats. In this study, we sought to explore the effects of locally administered vanadate on tensile strength and collagen organisation in both the early and remodelling phases of excisional wound healing in a murine model. Wild-type mice underwent stented excisional wounding on their dorsal skin and were divided equally into three treatment conditions: vanadate injection, saline injection control and an untreated control. Tensile strength testing, in vivo suction Cutometer analysis, gross wound measurements and histologic analysis were performed during healing, immediately upon wound closure, and after 4 weeks of remodelling. We found that vanadate treatment significantly increased the tensile strength of wounds and their stiffness relative to control wounds, both immediately upon healing and into the remodelling phase. Histologic analysis revealed that these biomechanical changes were likely the result of increased collagen deposition and an altered collagen organisation composed of thicker and distinctly organised collagen bundles. Given the risk that dehiscence poses to all operative patients, vanadate presents an interesting therapeutic avenue to improve the strength of post-operative wounds and unstable chronic wounds to reduce the risk of dehiscence.


Subject(s)
Surgical Wound , Wound Healing , Rats , Mice , Animals , Vanadates/pharmacology , Vanadates/metabolism , Vanadates/therapeutic use , Disease Models, Animal , Tensile Strength , Collagen/metabolism , Skin/injuries , Surgical Wound/metabolism
5.
Article in English | MEDLINE | ID: mdl-36345216

ABSTRACT

Significance: Half of all cancer patients receive radiation therapy as a component of their treatment regimen, and the most common resulting complication is radiation-induced fibrosis (RIF) of the skin and soft tissue. This thickening of the dermis paired with decreased vascularity results in functional limitations and esthetic concerns and poses unique challenges when considering surgical exploration or reconstruction. Existing therapeutic options for RIF of the skin are limited both in scope and efficacy. Cell-based therapies have emerged as a promising means of utilizing regenerative cell populations to improve both functional and esthetic outcomes, and even as prophylaxis for RIF. Recent Advances: As one of the leading areas of cell-based therapy research, adipose-derived stromal cells (ADSCs) demonstrate significant therapeutic potential in the treatment of RIF. The introduction of the ADSC-augmented fat graft has shown clinical utility. Recent research dedicated to characterizing specific ADSC subpopulations points toward further granularity in understanding of the mechanisms driving the well-established clinical outcomes seen with fat grafting therapy. Critical Issues: Various animal models of RIF demonstrated improved clinical outcomes following treatment with cell-based therapies, but the cellular and molecular basis underlying these effects remains poorly understood. Future Directions: Recent literature has focused on improving the efficacy of cell-based therapies, most notably through (1) augmentation of fat grafts with platelet-rich plasma and (2) the modification of expressed RNA through epitranscriptomics. For the latter, new and promising gene targets continue to be identified which have the potential to reverse the effects of fibrosis by increasing angiogenesis, decreasing inflammation, and promoting adipogenesis.

6.
J Transl Med ; 20(1): 274, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35715816

ABSTRACT

BACKGROUND: Radiation-induced skin injury is a well-known risk factor for impaired wound healing. Over time, the deleterious effects of radiation on skin produce a fibrotic, hypovascular dermis poorly suited to wound healing. Despite increasing understanding of the underlying pathophysiology, therapeutic options remain elusive. Deferoxamine (DFO), an iron-chelating drug, has been shown in prior murine studies to ameliorate radiation-induced skin injury as well as improve wound healing outcomes in various pathologic conditions when administered transdermally. In this preclinical study, we evaluated the effects of deferoxamine on wound healing outcomes in chronically irradiated murine skin. METHODS: Wild-type mice received 30 Gy of irradiation to their dorsal skin and were left to develop chronic fibrosis. Stented excisional wounds were created on their dorsal skin. Wound healing outcomes were compared across 4 experimental conditions: DFO patch treatment, vehicle-only patch treatment, untreated irradiated wound, and untreated nonirradiated wounds. Gross closure rate, wound perfusion, scar elasticity, histology, and nitric oxide assays were compared across the conditions. RESULTS: Relative to vehicle and untreated irradiated wounds, DFO accelerated wound closure and reduced the frequency of healing failure in irradiated wounds. DFO augmented wound perfusion throughout healing and upregulated angiogenesis to levels observed in nonirradiated wounds. Histology revealed DFO increased wound thickness, collagen density, and improved collagen fiber organization to more closely resemble nonirradiated wounds, likely contributing to the observed improved scar elasticity. Lastly, DFO upregulated inducible nitric oxide synthase and increased nitric oxide production in early healing wounds. CONCLUSION: Deferoxamine treatment presents a potential therapeutic avenue through which to target impaired wound healing in patients following radiotherapy.


Subject(s)
Deferoxamine , Radiation Injuries , Animals , Cicatrix/pathology , Collagen/pharmacology , Deferoxamine/pharmacology , Deferoxamine/therapeutic use , Humans , Mice , Nitric Oxide , Skin/pathology , Wound Healing
7.
J Surg Case Rep ; 2022(3): rjac066, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35280050

ABSTRACT

Hypertrophic scar formation and non-healing wounds following Achilles tendon repair arise from poor vascularity to the incisional site or from excess mechanical stress/strain to the incision during the healing process. The embrace® scar therapy dressing is a tension offloading device for incisional scars. This study explored the effects of tension offloading during Achilles scar formation. A healthy 30-year-old male without any medical co-morbidities developed an acute rupture of his left Achilles tendon. The patient underwent open repair 1 week after injury. At post-operative day (POD) 14, the patient started daily tension offloading treatment on the inferior portion of the incision through POD 120. By POD 120, the untreated portion of the Achilles incision appeared hypertrophic and hyperpigmented, while the treated portion of the scar appeared flat with minimal pigmentation changes. The 12-week treatment of tension offloading on an Achilles tendon repair incision significantly improved cosmesis compared to untreated incision.

8.
J Geriatr Psychiatry Neurol ; 34(4): 280-288, 2021 07.
Article in English | MEDLINE | ID: mdl-34219518

ABSTRACT

Mood disorders and anxiety significantly impact the prognosis and disease course of Parkinson's disease. Non-motor symptoms of Parkinson's disease such as apathy, anhedonia, and fatigue overlap with diagnostic criteria for anxiety and depression, thus making accurate diagnosis of mood disorders in Parkinson's disease patients difficult. Furthermore, treatment options for mood disorders can produce motor complications leading to poor adherence and impaired quality of life in Parkinson's disease patients. This review aims to clarify the current state of diagnostic and treatment options pertaining to anxiety and mood disorders in Parkinson's disease. It explores both the pharmacologic and non-pharmacologic treatment modalities for various mood disorders in comorbid Parkinson's disease with a brief discussion of the future outlook of the field given the current state of the literature.


Subject(s)
Mood Disorders , Parkinson Disease , Anxiety/epidemiology , Anxiety/therapy , Anxiety Disorders/diagnosis , Anxiety Disorders/epidemiology , Anxiety Disorders/therapy , Humans , Mood Disorders/epidemiology , Mood Disorders/therapy , Parkinson Disease/complications , Parkinson Disease/diagnosis , Parkinson Disease/epidemiology , Quality of Life
9.
Am J Case Rep ; 22: e931647, 2021 Jun 08.
Article in English | MEDLINE | ID: mdl-34101721

ABSTRACT

BACKGROUND Vancomycin is an antibiotic commonly used for management of severe gram-positive infections. It is infrequently associated with hematologic adverse effects, ranging from isolated thrombocytopenia or neutropenia to pancytopenia. Although the mechanism is poorly understood, it is considered an immune-mediated phenomenon. CASE REPORT A 46-year-old woman with a history of intravenous drug use presented having 2 months of lower back pain associated with new acute lower-extremity weakness, numbness, paresthesia, and urinary/fecal incontinence. Magnetic resonance imaging revealed L5-S1 osteomyelitis with an epidural phlegmon, and broad-spectrum antibiotic coverage, including vancomycin, was initiated. On day 33 of treatment, the patient was noted to have developed neutropenia, thrombocytopenia, and eosinophilia. Vancomycin was the suspected cause and was replaced with daptomycin; laboratory tests for alternative causes of the bicytopenia were negative. Resolution of the bicytopenia occurred 5 days after vancomycin was stopped, and the eosinophilia continued to improve. The Naranjo adverse drug reaction probability scale score was 6, deeming vancomycin as the "probable" cause. CONCLUSIONS Routine blood analysis during long-term vancomycin therapy is crucial to identifying hematologic suppression early. Prompt discontinuation of vancomycin is key to the management of the condition, with some case reports advocating for filgrastim adjuvant therapy to accelerate recovery. Cases of recurrence of the cytopenia with reexposure to vancomycin have been documented, and therefore inquiry into prior adverse reactions to vancomycin is recommended. Given the widespread use of vancomycin and the potential risks of bleeding and infection associated with thrombocytopenia and neutropenia, respectively, we caution physicians to be aware of this rare adverse effect in patients on long-term vancomycin therapy.


Subject(s)
Eosinophilia , Neutropenia , Thrombocytopenia , Anti-Bacterial Agents/adverse effects , Eosinophilia/chemically induced , Female , Humans , Middle Aged , Neutropenia/chemically induced , Neutropenia/drug therapy , Thrombocytopenia/chemically induced , Thrombocytopenia/drug therapy , Vancomycin/adverse effects
10.
Genesis ; 55(8)2017 08.
Article in English | MEDLINE | ID: mdl-28653435

ABSTRACT

Application of CRISPR-Cas9 technology in diverse organisms has resulted in an explosion of genome modification efforts. To expand the toolbox of applications, we have created an E. coli Exonuclease I (sbcB)-Cas9 fusion that has altered enzymatic activity in zebrafish embryos. This Cas9 variant has increased mutation efficiency and favors longer deletions relative to wild-type Cas9. We anticipate that this variant will allow for more efficient screening for F0 phenotypes and mutation of a larger spectrum of genomic targets including deletion of regulatory regions and creating loss of function mutations in transcription units with poor sequence conservation such as lncRNAs where larger deletions may be required for loss of function.


Subject(s)
Bacterial Proteins/genetics , CRISPR-Cas Systems , Endonucleases/genetics , Gene Targeting/methods , Zebrafish/genetics , Animals , Bacterial Proteins/metabolism , CRISPR-Associated Protein 9 , Endonucleases/metabolism , Gene Deletion , Gene Targeting/standards , Loss of Function Mutation
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