N-acetylcysteine for the prevention of stricture after circumferential endoscopic submucosal dissection of the esophagus: a randomized trial in a porcine model
© Barret et al.; licensee BioMed Central Ltd. 2012
Received: 14 February 2012
Accepted: 11 April 2012
Published: 28 May 2012
Circumferential endoscopic submucosal dissection (CESD) of the esophagus would allow for both the eradication of Barrett’s esophagus and its related complications, such as advanced neoplasia. However, such procedures generally induce inflammatory repair resulting in a fibrotic stricture. N-acetylcysteine (NAC) is an antioxidant that has shown some efficacy against pulmonary and hepatic fibrosis. The aim of our study was to evaluate the benefit of NAC in the prevention of esophageal cicatricial stricture after CESD in a swine model.
Animals and methods
Two groups of six pigs each were subjected to general anesthesia and CESD: after randomization, a first group received an oral NAC treatment regimen of 100 mg/kg/day, initiated one week before the procedure, whereas a second group was followed without any prophylactic treatment. Follow-up endoscopies took place seven, fourteen, twenty-one, and twenty-eight days after CESD. Necropsy, histological assessment of esophageal inflammation, and fibrosis were performed on day 28.
The median esophageal lumen diameter on day 21 (main judgment criterion) was 4 mm (range 2 to 5) in group 1 and 3 mm (range 1 to 7) in group 2 (P = 0.95). No significant difference was observed between the two groups regarding clinical evaluation (time before onset of clinically significant esophageal obstruction), number of dilations, esophageal inflammation and fibrosis, or oxidative stress damage on immunohistochemistry.
Despite its antioxidant effect, systemic administration of NAC did not show significant benefit on esophageal fibrosis in our animal model of esophageal wound healing within the experimental conditions of this study. Since the administered doses were relatively high, it seems unlikely that NAC might be a valuable option for the prevention of post-endoscopic esophageal stricture.
KeywordsEndoscopic submucosal dissection (ESD) Esophageal stricture Esophageal fibrosis Barrett’s esophagus Early esophageal adenocarcinoma
Endoscopic resection of Barrett’s esophagus with a high-grade dysplasia or early esophageal cancer has become an acceptable therapeutic option [1–3], alongside surgical esophagectomy. Endoscopic mucosal resection is easily feasible but leads to a piecemeal, non-carcinologic resection of neoplastic tissue, whereas endoscopic submucosal dissection (ESD) is more carcinologically efficient, although more technically challenging. Nonetheless, both techniques result in cicatricial fibroinflammatory esophageal strictures when 75% or more of the mucosal circumference is removed [4, 5]. These strictures may require numerous endoscopic dilations, jeopardizing the patients’ quality of life and risking esophageal perforation. This is believed to result from local inflammatory reactions, as well as subsequent cicatricial fibrosis [4, 6–8]. Furthermore, pathological wound healing and fibrogenesis in the esophagus has been linked to the production of reactive oxygen species .
We developed an endoscopic submucosal dissection technique in a swine model, allowing for quick and safe en bloc circumferential resection of the esophageal mucosa . A similar technique has been described since . This method consists of a classical endoscopic submucosal dissection and blunt mechanical dissection using an endoscopic mucosectomy cap. It allows for en bloc resection of mucosal and submucosal cylinders up to 15 centimeters, without taking longer or causing more immediate complications than endoscopic mucosal resection alone. However, tight oesophageal strictures always develop in this model between the eighth and the fifteenth postoperative day.
N-acetylcysteine (NAC) is an antioxidant molecule with antifibrotic properties [12, 13], mainly related to the inhibition of transforming growth factor-beta (TGF-β) signaling . It has an anti-inflammatory effect caused by downregulating TNF-α, IL-6, and IL-8 synthesis . Furthermore, it is a cheap, readily available, and a safe molecule. NAC has shown efficiency in pulmonary fibrosis  and is of possible interest in cirrhotic , nonalcoholic steatohepatitis  liver fibrosis, and improved wound healing of tympanic membranes . In the esophagus, anastomotic wound healing improved with NAC administration .
Therefore, we conducted a controlled trial to assess the interest of NAC in the prevention of esophageal strictures, following circumferential ESD in our swine model.
In group 1, none of the six animals exhibited abnormal behavior, but five out of six (83%) were unable to ingest a regular diet after fourteen days because of regurgitations. In group 2, one pig out of five (20%) was found to be asthenic, and four out of five (80%) were unable to eat because of their esophageal stricture. Overall number of dilation was 13 (2.2 per pig) in group 1 and 12 (2 per pig) in group 2 on day 21 (P = NS).
Number of esophageal dilations and occurrence of complications
Number of dilations
Post-endoscopic esophageal perforation, requiring euthanasia
Mediastinitis on day 22, following the third dilation
Post-endoscopic esophageal perforation, successfully treated
Mediastinal inflammation+ at necropsy
Mediastinal inflammation+ at necropsy
This study is the first one to evaluate, on a swine model, the systemic administration of an antioxidant molecule in the prevention of esophageal strictures.
Nonetheless, this work did not demonstrate any clinical, endoscopical, or histological benefit of NAC to prevent oesophageal stenosis after circumferential ESD. A first hypothesis is an insufficient oral intake of NAC in regurgitating animals, despite repeated esophageal dilations. However, if solid food intake is impaired by esophageal stricture, liquid intake is almost always possible. Moreover, food intake remained normal during the first 10 days, the period during which NAC was expected to exert its maximal beneficial effect, if any. An intravenous route for NAC would have required daily invasive treatment administration, and sedation of the animals, which did not seem acceptable; furthermore, oral and intravenous administrations have been reported to be equivalent . Doses of NAC vary from 20 mg/kg to 400 mg/kg of body weight per day. Given that the bioavailability of orally administrated NAC is low (<10%), we decided to use high doses, closer to those used in acetaminophen poisoning than in chronic fibrotic diseases . The pigs were put on a 60 mg/kg/day dose of NAC as part of a preliminary experiment and results showed improvement of the esophageal diameter at day 15 with no side effects. This propelled us to increase the NAC dose to 100 mg/kg/day. The use of higher doses, up to 400 mg/kg/day, has been reported, but is commonly associated with frequent side effects . Such anaphylactoïd reactions, including vomiting, could have biased the evaluation of food intake, esophageal mucosa, and symptoms related to esophageal stricture. We did not record such anaphylactoïd reactions in the animals we treated. However, insufficient local concentration could also explain these results and could warrant another attempt of NAC administration, directly into esophageal wounds.
The second issue is the timing of the clinical and histological assessment. We chose the 21st postoperative day as the day of endpoint assessment because it was consistent with the timing of stricture development in this model, generally observable between days 10 and 15 after ESD. Animals were kept in good condition after day 15, using iterative endoscopic dilations. Of note is the fact that these dilations might have played a role in the delayed reepithelialisation observed in some animals. It can be hypothesized that an earlier assessment of clinical and histological endpoints might have shown a more significantly different data, but the absence of any observable benefit at 21 days suggests such findings would not have been highly relevant to further clinical use of NAC.
A third hypothesis for NAC inefficiency is the severe and systematic nature of oesophageal strictures in pigs (possibly due to continuous acid aggression in conditions of stress). This makes our swine model particularly heuristic for the study of stricture development and prevention: if a treatment provides positive clinical results in this model, it should be all the more efficient in humans, but one would expect that NAC should at least exhibit some histological effect.
NAC has been found to have a direct antioxidant effect as well as to stimulate glutathione synthesis, a major endogenous intracellular antioxidant. It also plays a role in modulating the proinflammatory cytokine response , notably by inhibiting TGF-β1  and abrogating the fibrogenic properties of pathological fibroblasts . Post-endoscopic esophageal strictures are characterized by an intense local inflammatory reaction, which prevents reepithelialisation taking place and quickly makes way for cicatricial fibrosis. An increased level of reactive oxygen species (ROS) has been reported in esophageal ulcers, with the benefit of an antioxidant molecule (vitamin E) administration on esophageal wound healing ; along with these results, many stricture-preventing drugs, either antioxidant , antifibrotic [26–30], or anti-inflammatory [4, 7, 31], have been tested on esophageal wounds. The only treatment reported to be beneficial against esophageal strictures in human studies is local corticosteroid injection , although these results are contradictory, with previous animal studies reporting severe complications related to triamcinolone injection . These data have led us to consider NAC for post-endoscopic esophageal stricture prevention. Despite an antioxidant effect suggested by the results of immunohistochemistry (although the difference between both signals on quantitative measurements did not reach statistical significance), NAC did not, in our work, prevent esophageal stricture.
Considering our results, it seems that several mechanisms could be at stake in cicatricial esophageal fibrosis. In particular, mucosal defect and resulting acid, and bacterial aggressions of the submucosa could play a role; therefore, stricture prevention strategies focusing on covering and protecting the injured esophagus should be developed, even if recent studies, including ones done on humans, either report insufficient efficacy , or show an improvement of esophageal wound healing only in partial mucosal defects [7, 8, 33–35], where strictures are uncommon. However, the use of growth factors, extracellular membranes, or bio-scaffolds or cellular therapy, makes their translation into daily practice unlikely for the present moment. This data confirm that preventive treatment should prevail against curative ones regarding post-endoscopic esophageal strictures.
Our study failed to prove that an antioxidant such as NAC can improve the outcome of tissue repair in a model of severe post-ESD esophageal stricture, when used as a single agent. Its antioxidant activity did not prevent fibroinflammatory cicatricial esophageal stricture formation at the 21st postoperative day. Extensive esophageal endoscopic submucosal dissection might become an alternative choice to esophagectomy for Barrett’s esophagus with high-grade dysplasia or early adenocarcinoma; hence, further analysis of esophageal wound healing will be needed, in order to develop new stricture-preventing treatments.
The experimental protocol received approval from the scientific committee of the Surgical School of Paris (Ecole de Chirurgie de l’ Assistance Publique des Hôpitaux de Paris, 7 rue du Fer à Moulin, 75005 Paris, France), and experiments were performed according to the standard guidelines of the French Ministry of Agriculture that regulates animal research in France.
Twelve 30 to 35 kg pigs, originating from the same farm, were used in the study. The pigs were accommodated at our facility 48 hours before the procedure took place. Endoscopies were performed under general anesthesia. All animals were prepared for anesthesia with a 12-hour diet and were administered an intramuscular injection of 10 mg/kg ketamine and 2 mg/kg azaperone, 30 minutes before induction. Following induction with 8 mg/kg intravenous 1% propofol and endotracheal intubation, anesthesia was maintained through inhalation of 1% to 2% isoflurane. All animals received an intravenous infusion of 10 mg/kg/h crystalloid solution.
Endoscopic submucosal dissection procedure
Upper gastrointestinal endoscopies were performed using a standard gastroscope (Fujinon EG450D; Fujinon, Sataima, Japan), through an overtube. A senior endoscopist carried out and/or directly supervised the procedure at all times. Circumferential submucosal endoscopic dissection of the distal third of the esophagus was performed according to the previously reported technique . Briefly, two circumferential incisions reaching the superficial submucosal layer were made following a submucosal injection of indigo carmine-stained saline; these two incisions defined a mucosal cylinder of 5 cm in the lower third of the esophagus, 5 cm above the gastroesophageal junction. The cylinder was removed by blunt submucosal dissection, using a mucosectomy cap (ST hood DH-19 GR; Fujinon, Sataima, Japan), which allowed for cleaving of the mucosa and superficial submucosa from the underlying submucosa by gently scraping the esophageal wall in a back and forth motion, from the proximal to the distal incision. The resected mucosal cylinder was then retrieved using the endoscope’s suction channel.
Twelve pigs were randomly allocated to a treatment and a control group. The first group of six pigs was given 100 mg/kg/day of NAC (Mucomyst; Bristol-Myers Squibb, Princeton, NJ, USA) in drinking water for seven days before the procedure. After circumferential endoscopic submucosal dissection (CESD), the pigs received NAC treatment, at the same dose, until the 21st postoperative day. A seven-day course of omeprazole 40 mg/day and broad-spectrum antibiotics was also given: 10 mg/kg extended-release benzathine benzylpenicillin G + penicillin procaine (Duphapen; Pfizer, NewYork, NY, USA) for the first four days; then 1 g/day amoxicillin (Clamoxyl®, GlaxoSmithKline, Brentford, UK) for three days. The control group (group 2) received proton-pump inhibitors and broad-spectrum antibiotics at the same doses.
The animals were given a liquid diet following each procedure, and were gradually introduced to a solid food diet. The pigs were kept in the Surgical School of Paris with daily examination and weekly veterinary follow-up and endoscopic examination. An endoscopic balloon dilation was performed if clinical symptoms suggested that an esophageal stricture had occurred. Investigators prospectively collected clinical data on a weekly basis, such as global clinical status, which included general behavior, food intake, and occurrence of regurgitations or vomiting. Investigators also recorded any endoscopic findings, width of esophageal lumen (evaluated with a biopsy forceps), and number of balloon dilations.
Twenty-eight days after the procedure, or earlier in case of major complication (esophageal perforation, death), animals were euthanized with 100 mg/kg intravenous injection of 7 mg pentobarbital (Dolethal; Vétoquinol, Paris, France), and underwent a necropsy with esophagectomy afterward.
Specimens were fixed in 10% buffered formalin, embedded in paraffin, and processed into 5 μm-thick sections, after gross morphological examination of the size, weight, and thickness of the esophageal wall. The specimens were then stained with hematoxylin-eosin-safran (HES), and Masson’s trichrome. Histological slides were digitized with the NDPI Nanozoomer (Hamamatsu Photonics, Hamamatsu City, Japan), and submitted to quantitative analysis of fibrosis, granulation tissue, and inflammatory cell infiltrate by a senior pathologist expert in digestive pathology. The following measurements were made on each digitized image of trichrome-stained slides: maximal thickness of fibrosis, from the muscularis propria to the epithelium, and maximal thickness of the granulation tissue, from the esophageal lumen to the submucosal fibrosis. Furthermore, the inflammatory cell infiltrate was characterized as being acute (predominance of polynuclear cells, high cell density) or chronic (predominance of lymphocytes or plasmocytes, low cell density).
Immunohistochemistry on paraffin sections was performed with monoclonal antibodies to 8-hydroxy-2’ deoxyguanosine (8-OH DG) (ab26842; Abcam, Cambridge, UK) and goat polyclonal secondary antibodies to mouse IgG1 (ab 97240; Abcam, Cambridge, UK), in order to assess the intensity of oxidative stress in the esophageal wall. The intensity of the signal was analyzed using the ImageJ software, the highest numbers corresponding to the lowest signal.
Statistical analysis was performed using GraphPad Prism (GraphPad Software, La Jolla, CA, USA). Continuous data is expressed as median values and range, and compared with a nonparametric Mann–Whitney test. Categorical data is expressed in percentages and compared with a Fisher’s exact test.
The primary end point was the diameter of the esophagus measured via endoscopy on day 21 following the operation.
The secondary end points were: global clinical evaluation of the pigs on day 21, number of endoscopic dilations required, thickness of the granulation tissue and the fibrotic layer in the esophageal wall, and antioxidant effect of NAC, as measured by 8-OH DG staining.
Circumferential endoscopic submucosal dissection
Reactive oxygen species
- 8-OH DG:
Transforming growth factor
Tumor necrosis factor-alpha.
The authors thank Mrs Michelle Reichard and Mr Antoine Dechezleprêtre for their help in the preparation of the manuscript.
- Chennat J, Konda VJ, Ross AS, de Tejada AH, Noffsinger A, Hart J, Lin S, Ferguson MK, Posner MC, Waxman I: Complete Barrett's eradication endoscopic mucosal resection: an effective treatment modality for high-grade dysplasia and intramucosal carcinoma–an American single-center experience. Am J Gastroenterol. 2009, 104: 2684-2692. 10.1038/ajg.2009.465.View ArticlePubMedGoogle Scholar
- Ell C, May A, Pech O, Gossner L, Guenter E, Behrens A, Nachbar L, Huijsmans J, Vieth M, Stolte M: Curative endoscopic resection of early esophageal adenocarcinomas (Barrett's cancer). Gastrointest Endosc. 2007, 65: 3-10. 10.1016/j.gie.2006.04.033.View ArticlePubMedGoogle Scholar
- Pech O, May A, Gossner L, Rabenstein T, Manner H, Huijsmans J, Vieth M, Stolte M, Berres M, Ell C: Curative endoscopic therapy in patients with early esophageal squamous-cell carcinoma or high-grade intraepithelial neoplasia. Endoscopy. 2007, 39: 30-35. 10.1055/s-2006-945040.View ArticlePubMedGoogle Scholar
- Hashimoto S, Kobayashi M, Takeuchi M, Sato Y, Narisawa R, Aoyagi Y: The efficacy of endoscopic triamcinolone injection for the prevention of esophageal stricture after endoscopic submucosal dissection. Gastrointest Endosc. 2011, 74: 1389-1393. 10.1016/j.gie.2011.07.070.View ArticlePubMedGoogle Scholar
- Katada C, Muto M, Manabe T, Boku N, Ohtsu A, Yoshida S: Esophageal stenosis after endoscopic mucosal resection of superficial esophageal lesions. Gastrointest Endosc. 2003, 57: 165-169. 10.1067/mge.2003.73.View ArticlePubMedGoogle Scholar
- Nieponice A, McGrath K, Qureshi I, Beckman EJ, Luketich JD, Gilbert TW, Badylak SF: An extracellular matrix scaffold for esophageal stricture prevention after circumferential EMR. Gastrointest Endosc. 2009, 69: 289-296. 10.1016/j.gie.2008.04.022.View ArticlePubMedGoogle Scholar
- Rajan E, Gostout C, Feitoza A, Herman L, Knipschield M, Burgart L, Chung S, Cotton P, Hawes R, Kalloo A, Kantsevoy S, Pasricha P: Widespread endoscopic mucosal resection of the esophagus with strategies for stricture prevention: a preclinical study. Endoscopy. 2005, 37: 1111-1115. 10.1055/s-2005-870531.View ArticlePubMedGoogle Scholar
- Sakurai T, Miyazaki S, Miyata G, Satomi S, Hori Y: Autologous buccal keratinocyte implantation for the prevention of stenosis after EMR of the esophagus. Gastrointest Endosc. 2007, 66: 167-173. 10.1016/j.gie.2006.12.062.View ArticlePubMedGoogle Scholar
- Gunel E, Caglayan F, Caglayan O, Canbilen A, Tosun M: Effect of antioxidant therapy on collagen synthesis in corrosive esophageal burns. Pediatr Surg Int. 2002, 18: 24-27. 10.1007/s003830200005.View ArticlePubMedGoogle Scholar
- Prat F, Chryssostalis A, Chaussade S: Esophageal Circumferential En-Bloc Submucosal Dissection in a Porcine Model. Digestive Disease Week. 2006, Los Angeles:Gastrointest Endosc, AB133.Google Scholar
- Willingham FF, Gee DW, Sylla P, Lauwers GY, Rattner DW, Brugge WR: En bloc esophageal mucosectomy for concentric circumferential mucosal resection (with video). Gastrointest Endosc. 2009, 69: 147-151. 10.1016/j.gie.2008.09.010.View ArticlePubMedGoogle Scholar
- Knobloch K, Redeker J, Vogt PM: Antifibrotic medication using a combination of N-acetyl-L-cystein (NAC) and ACE inhibitors can prevent the recurrence of Dupuytren's disease. Med Hypotheses. 2009, 73: 659-661. 10.1016/j.mehy.2009.08.011.View ArticlePubMedGoogle Scholar
- Servettaz A, Goulvestre C, Kavian N, Nicco C, Guilpain P, Chereau C, Vuiblet V, Guillevin L, Mouthon L, Weill B, Batteux F: Selective oxidation of DNA topoisomerase 1 induces systemic sclerosis in the mouse. J Immunol. 2009, 182: 5855-5864. 10.4049/jimmunol.0803705.View ArticlePubMedGoogle Scholar
- Kopp J, Seyhan H, Muller B, Lanczak J, Pausch E, Gressner AM, Dooley S, Horch RE: N-acetyl-L-cysteine abrogates fibrogenic properties of fibroblasts isolated from Dupuytren's disease by blunting TGF-beta signalling. J Cell Mol Med. 2006, 10: 157-165. 10.1111/j.1582-4934.2006.tb00297.x.PubMed CentralView ArticlePubMedGoogle Scholar
- Del Sorbo L, Zhang H: Is there a place for N-acetylcysteine in the treatment of septic shock?. Crit Care. 2004, 8: 93-95. 10.1186/cc2450.PubMed CentralView ArticlePubMedGoogle Scholar
- Demedts M, Behr J, Buhl R, Costabel U, Dekhuijzen R, Jansen HM, MacNee W, Thomeer M, Wallaert B, Laurent F, Nicholson AG, Verbeken EK, Verschakelen J, Flower CD, Capron F, Petruzzelli S, De Vuyst P, van den Bosch JM, Rodriguez-Becerra E, Corvasce G, Lankhorst I, Sardina M, Montanari M, IFIGENIA Study Group: High-dose acetylcysteine in idiopathic pulmonary fibrosis. N Engl J Med. 2005, 353: 2229-2242. 10.1056/NEJMoa042976.View ArticlePubMedGoogle Scholar
- Vercelino R, Crespo I, de Souza GF, Cuevas MJ, de Oliveira MG, Marroni NP, Gonzalez-Gallego J, Tunon MJ: S-nitroso-N-acetylcysteine attenuates liver fibrosis in cirrhotic rats. J Mol Med (Berl). 2010, 88: 401-411. 10.1007/s00109-009-0577-6.View ArticleGoogle Scholar
- Baumgardner JN, Shankar K, Hennings L, Albano E, Badger TM, Ronis MJ: N-acetylcysteine attenuates progression of liver pathology in a rat model of nonalcoholic steatohepatitis. J Nutr. 2008, 138: 1872-1879.PubMed CentralPubMedGoogle Scholar
- Ozcan C, Gorur K, Cinel L, Talas DU, Unal M, Cinel I: The inhibitory effect of topical N-acetylcysteine application on myringosclerosis in perforated rat tympanic membrane. Int J Pediatr Otorhinolaryngol. 2002, 63: 179-184. 10.1016/S0165-5876(01)00640-1.View ArticlePubMedGoogle Scholar
- Demir EO, Cakmak GK, Bakkal H, Turkcu UO, Kandemir N, Demir AS, Tascilar O: N-acetyl-cysteine improves anastomotic wound healing after radiotherapy in rats. J Investig Surg. 2011, 24: 151-158. 10.3109/08941939.2011.560237.View ArticleGoogle Scholar
- Buckley NA, Whyte IM, O'Connell DL, Dawson AH: Oral or intravenous N-acetylcysteine: which is the treatment of choice for acetaminophen (paracetamol) poisoning?. J Toxicol Clin Toxicol. 1999, 37: 759-767. 10.1081/CLT-100102453.View ArticlePubMedGoogle Scholar
- Heard KJ: Acetylcysteine for acetaminophen poisoning. N Engl J Med. 2008, 359: 285-292. 10.1056/NEJMct0708278.PubMed CentralView ArticlePubMedGoogle Scholar
- Knudsen TT, Thorsen S, Jensen SA, Dalhoff K, Schmidt LE, Becker U, Bendtsen F: Effect of intravenous N-acetylcysteine infusion on haemostatic parameters in healthy subjects. Gut. 2005, 54: 515-521. 10.1136/gut.2004.043505.PubMed CentralView ArticlePubMedGoogle Scholar
- Moldeus P: Cotgreave IA: N-acetylcysteine. Methods Enzymol. 1994, 234: 482-492.View ArticlePubMedGoogle Scholar
- Koltuksuz U, Mutus HM, Kutlu R, Ozyurt H, Cetin S, Karaman A, Gurbuz N, Akyol O, Aydin NE: Effects of caffeic acid phenethyl ester and epidermal growth factor on the development of caustic esophageal stricture in rats. J Pediatr Surg. 2001, 36: 1504-1509. 10.1053/jpsu.2001.27032.View ArticlePubMedGoogle Scholar
- Apaydin BB, Paksoy M, Artis T, Sahin DA, Aki H, Uslu E: Influence of pentoxifylline and interferon-alpha on prevention of stricture due to corrosive esophagitis. An experimental study in the rat. Eur Surg Res. 2001, 33: 225-231. 10.1159/000049710.View ArticlePubMedGoogle Scholar
- Cakmak M, Nayci A, Renda N, Erekul S, Gokcora H, Yucesan S: The effect of corticosteroids and pentoxifylline in caustic esophageal burns. A prospective trial in rats. Int Surg. 1997, 82: 371-375.PubMedGoogle Scholar
- Mizutani T, Tadauchi A, Arinobe M, Narita Y, Kato R, Niwa Y, Ohmiya N, Itoh A, Hirooka Y, Honda H, Ueda M, Goto H: Novel strategy for prevention of esophageal stricture after endoscopic surgery. Hepatogastroenterology. 2010, 57: 1150-1156.PubMedGoogle Scholar
- Ozcelik MF, Pekmezci S, Saribeyoglu K, Unal E, Gumustas K, Dogusoy G: The effect of halofuginone, a specific inhibitor of collagen type 1 synthesis, in the prevention of esophageal strictures related to caustic injury. Am J Surg. 2004, 187: 257-260. 10.1016/j.amjsurg.2003.11.008.View ArticlePubMedGoogle Scholar
- Turkyilmaz Z, Sonmez K, Demirtola A, Karabulut R, Poyraz A, Gulen S, Dincer S, Basaklar AC, Kale N: Mitomycin C prevents strictures in caustic esophageal burns in rats. J Surg Res. 2005, 123: 182-187. 10.1016/j.jss.2004.08.009.View ArticlePubMedGoogle Scholar
- Honda M, Nakamura T, Hori Y, Shionoya Y, Nakada A, Sato T, Yamamoto K, Kobayashi T, Shimada H, Kida N, Hashimoto A, Hashimoto Y: Process of healing of mucosal defects in the esophagus after endoscopic mucosal resection: histological evaluation in a dog model. Endoscopy. 2010, 42: 1092-1095. 10.1055/s-0030-1255741.View ArticlePubMedGoogle Scholar
- Badylak SF, Hoppo T, Nieponice A, Gilbert TW, Davison JM, Jobe BA: Esophageal preservation in five male patients after endoscopic inner-layer circumferential resection in the setting of superficial cancer: a regenerative medicine approach with a biologic scaffold. Tissue Eng Part A. 2011, 17: 1643-1650. 10.1089/ten.tea.2010.0739.PubMed CentralView ArticlePubMedGoogle Scholar
- Baatar D, Kawanaka H, Szabo IL, Pai R, Jones MK, Kitano S, Tarnawski AS: Esophageal ulceration activates keratinocyte growth factor and its receptor in rats: implications for ulcer healing. Gastroenterology. 2002, 122: 458-468. 10.1053/gast.2002.31004.View ArticlePubMedGoogle Scholar
- Nieponice A, Gilbert TW, Badylak SF: Reinforcement of esophageal anastomoses with an extracellular matrix scaffold in a canine model. Ann Thorac Surg. 2006, 82: 2050-2058. 10.1016/j.athoracsur.2006.06.036.View ArticlePubMedGoogle Scholar
- Ohki T, Yamato M, Murakami D, Takagi R, Yang J, Namiki H, Okano T, Takasaki K: Treatment of oesophageal ulcerations using endoscopic transplantation of tissue-engineered autologous oral mucosal epithelial cell sheets in a canine model. Gut. 2006, 55: 1704-1710. 10.1136/gut.2005.088518.PubMed CentralView ArticlePubMedGoogle Scholar
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