scholarly journals Development of a porcine model for assessment of mucosal repair following endoscopic resection of the lower gastrointestinal tract

2017 ◽  
Vol 05 (10) ◽  
pp. E1014-E1019 ◽  
Author(s):  
Nicolas Etchepare ◽  
Jérémy Bregeon ◽  
Lucille Quénéhervé ◽  
Sami Haddara ◽  
Yann Touchefeu ◽  
...  

Abstract Background and aims Endoscopic mucosal resection (EMR) is widely performed for the treatment of colorectal polyps. However, the pathophysiological mechanisms of mucosal repair, including in situations at high risk of post-polypectomy bleeding, remain largely unknown. The objective of our study was to develop a porcine model of EMR in the lower gastrointestinal tract to monitor mucosal wound healing over time. Methods Under general anesthesia, five large wounds were created in the lower gastrointestinal tract at different times, i. e. at day 0, 3, 7, 10, and 14, by multiband EMR, in each of the six pigs in the study. A colorectal resection was performed at day 14 and the animal euthanized. Repeated endoscopic and endomicroscopic examination, and histological analysis were performed. Results No complications occurred and all animals reached the study end point. The endoscopic aspect of wound healing evolved into different phases with first a fibrin deposit covering the wounds which then gave way to granulomatous tissue. The size of the wound regressed significantly as early as day 3. Re-epithelialization of the wound started from day 7, and neo-mucosal crypts appeared from day 10. The endomicroscopic analysis described a ‘ground glass appearance’ from day 3 and irregular crypts from day 10, which was consistent with histological data. Good agreement between macroscopic, endomicroscopic, and histological parameters of mucosal wound healing was observed in vivo. Conclusion This study demonstrates for the first time the feasibility of an experimental in vivo porcine model of lower gastrointestinal endoscopic resections to monitor tissue repair. This model might be helpful to document pharmacological approaches for preventing complications of endoscopic procedures performed in humans.

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 708
Author(s):  
Radek Sleha ◽  
Vera Radochova ◽  
Jiri Malis ◽  
Alexander Mikyska ◽  
Milan Houska ◽  
...  

Staphylococcus (S.) aureus is an important causative agent of wound infections with increasing incidence in the past decades. Specifically, the emergence of methicillin-resistant S. aureus (MRSA) causes serious problems, especially in nosocomial infections. Therefore, there is an urgent need to develop of alternative or supportive antimicrobial therapeutic modalities to meet these challenges. Purified compounds from hops have previously shown promising antimicrobial effects against MRSA isolates in vitro. In this study, purified beta-acids from hops were tested for their potential antimicrobial and healing properties using a porcine model of wounds infected by MRSA. The results show highly significant antimicrobial effects of the active substance in both the powder and Ambiderman-based application forms compared to both no-treatment control and treatment with Framycoin. Moreover, the macroscopic evaluation of the wounds during the treatment using the standardized Wound Healing Continuum indicated positive effects of the beta-acids on the overall wound healing. This is further supported by the microscopic data, which showed a clear improvement of the inflammatory parameters in the wounds treated by beta-acids. Thus, using the porcine model, we demonstrate significant therapeutic effects of hops compounds in the management of wounds infected by MRSA. Beta-acids from hops, therefore, represent a suitable candidate for the treatment of non-responsive nosocomial tissue infections by MRSA.


2019 ◽  
Author(s):  
Tiffany Chien ◽  
Tetsuhiro Harimoto ◽  
Benjamin Kepecs ◽  
Kelsey Gray ◽  
Courtney Coker ◽  
...  

AbstractThe engineering of microbes spurs biotechnological innovations, but requires control mechanisms to confine growth within defined environments for translation. Here we engineer bacterial growth tropism to sense and grow in response to specified oxygen, pH, and lactate signatures. Coupling biosensors to drive essential gene expression reveals engineered bacterial localization within upper or lower gastrointestinal tract. Multiplexing biosensors in an AND logic-gate architecture reduced bacterial off-target colonization in vivo.


2012 ◽  
Vol 17 (02) ◽  
pp. 1 ◽  
Author(s):  
Wibool Piyawattanametha ◽  
Hyejun Ra ◽  
Kevin E. Loewke ◽  
Michael J. Mandella ◽  
Christopher H. Contag ◽  
...  

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Michelle Reed ◽  
Anny-Claude Luissint ◽  
Veronica Azcutia ◽  
Shuling Fan ◽  
Monique N. O’Leary ◽  
...  

Abstract CD47 is a ubiquitously expressed transmembrane glycoprotein that regulates inflammatory responses and tissue repair. Here, we show that normal mice treated with anti-CD47 antibodies, and Cd47-null mice have impaired intestinal mucosal wound healing. Furthermore, intestinal epithelial cell (IEC)-specific loss of CD47 does not induce spontaneous immune-mediated intestinal barrier disruption but results in defective mucosal repair after biopsy-induced colonic wounding or Dextran Sulfate Sodium (DSS)-induced mucosal damage. In vitro analyses using primary cultures of CD47-deficient murine colonic IEC or human colonoid-derived IEC treated with CD47-blocking antibodies demonstrate impaired epithelial cell migration in wound healing assays. Defective wound repair after CD47 loss is linked to decreased epithelial β1 integrin and focal adhesion signaling, as well as reduced thrombospondin-1 and TGF-β1. These results demonstrate a critical role for IEC-expressed CD47 in regulating mucosal repair and raise important considerations for possible alterations in wound healing secondary to therapeutic targeting of CD47.


Author(s):  
Ray Hachem ◽  
Umang M. Parikh ◽  
Ruth Reitzel ◽  
Joel Rosenblatt ◽  
Aditya Kaul ◽  
...  

Author(s):  
Igor Snast ◽  
Moshe Lapidoth ◽  
Assi Levi

Abstract The sequential application of fractional ablative/10,600 nm/CO2 followed by 1570 nm non-ablative laser treatment might produce better results than applying either laser treatment alone. However, histological data regarding the safety of this combination is lacking. This study aimed to assess and compare clinical effects, histological tissue damage, and wound healing after monochromatic and sequential fractional laser treatments. In this prospective porcine model study, three adult female pigs were each irradiated using three different wavelengths: (a) monochromatic fractional ablative CO2 laser; (b) monochromatic fractional non-ablative 1570 nm laser; (c) sequential fractional 10,600 nm/CO2 followed by 1570 nm laser treatment. There were six power levels in the monochromatic 1570 nm laser, five in the 10,600 nm/CO2, and five in the sequential treatment. The immediate skin reaction (ISR), crusting and adverse effects, was evaluated across different time points throughout the healing process. Wound biopsies were taken at immediately after (0) and at 3, 7, and 14 days after irradiation. Depth and width of craters, and width of coagulation zone were measured and compared. Similar ISR and crusting score values were obtained following the monochromatic and sequential irradiation in a similar dose–response manner. During 14 days of follow-up, the skin looked intact and non-infected with no signs of necrosis. The mean depth and width of craters were comparable only at the maximal energy level (240 mJ) of CO2 laser, with the coagulation size greater after the sequential treatment. In histology, a similar wound healing was evident. On day 3, crusts were observed above all lesions as was epithelial regeneration. The sequential irradiation with 10,600 nm/CO2 and 1570 nm lasers did not pose any additional risk compared to the risk of each laser alone.


Author(s):  
Nicole Dmochowska ◽  
Hannah R. Wardill ◽  
Patrick A. Hughes

Inflammatory Bowel Disease (IBD) is characterized by chronic remitting and relapsing inflammation of the lower gastrointestinal tract. The etiology underlying IBD remains unknown but is thought to involve a hypersensitive immune response to environmental antigen, including the microbiota. Diagnosis and monitoring of disease is heavily reliant on endoscopy, which is invasive and does not provide information regarding specific mediators. This review describes recent developments in imaging of IBD with a focus on PET and SPECT imaging of inflammatory mediators, and how this may be applied to the microbiota.


2020 ◽  
Vol 31 (6) ◽  
pp. 407-418 ◽  
Author(s):  
Sven Flemming ◽  
Anny-Claude Luissint ◽  
Dennis H. M. Kusters ◽  
Arturo Raya-Sandino ◽  
Shuling Fan ◽  
...  

We report a key role for Dsc2 in simple epithelial cell migration and mucosal wound healing in vivo using newly generated mice with inducible conditional knockdown of Dsc2 in intestinal epithelial cells ( Villin-CreERT2; Dsc2fl/fl).


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