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Publications (4)3.37 Total impact

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    ABSTRACT: The limited application of small bowel transplantation for short bowel syndrome, mainly on the account of the morbidity and long-term implications of the procedure, has led to a search for alternative therapies. The purpose of this study was to evaluate whether basic fibroblast growth factor (bFGF) could facilitate regeneration of fetal small intestinal mucosa in vivo. Intestinal epithelial organoid units harvested from fetal Lewis rats were injected into adult male Lewis rats whose colon was denuded of mucosa, as syngeneic recipients. One experimental group transplanted with the addition of 50 ng/ml bFGF, was compared with a control group that were transplanted without bFGF. The grafts were harvested and analyzed using histology and immunohistochemistry 3 weeks after operation. There were 4 anesthetic deaths, two in each group, and 11 deaths due to adhesive ileus. In no rat did neomucosa fully cover the denuded colonic muscle throughout the whole length of lumen. Histologically, the structure of the neomucosa, when present, was normal small intestinal mucosa. The small intestinal mucosa was partially restored in 100% (6 of 6) of bFGF, and in 28.6% (2 of 7) of those not given bFGF (P = 0.0021). These data demonstrate that bFGF can facilitate the restoration of intestinal epithelial cells, at least to some degree. Potentially, refinements of this technique could be used to facilitate the physiologic tissue engineering of small intestine in a way that allows it to move peristaltically, and have an application in the management of patients with short bowel syndrome.
    Pediatric Surgery International 07/2009; 25(8):691-5. · 1.22 Impact Factor
  • Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) 01/2007; 68(5):1070-1076.
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    ABSTRACT: The mechanisms whereby grafts in the recipients can be primed for regeneration following living donor liver transplantation (LDLT) are poorly understood. The present study was designed to understand the mechanism for posttransplant regeneration in small-for-size liver graft. Out of LDLT cases, we examined patients with end-stage liver cirrhosis and subsequent transplantation. A total of 16 patients were divided into 2 groups, group L (large graft) and group S (small graft). We examined the serum biochemical markers and cytokines preoperatively and postoperatively. We also carried out hemodynamic analysis by measuring the portal and arterial peak velocity. The differences in ages, preoperative biochemical markers and MELD score between the two groups were not statistically significant. Though differences in the preoperative levels of IL-6, sIL-6R and HGF were not significant between the two groups, IL-6 and HGF levels in group S significantly increased postoperatively. Immediate and significant increase of Vp max was also observed in group S. Two weeks after LDLT, the regeneration rate in group S was significantly higher than that in group L. These findings may allow us to speculate that immediate increase of portal pressure, reflecting sinusoidal tensile/shear stress, accelerates liver regeneration through immediate induction of IL-6 and HGF.
    Hepato-gastroenterology 01/2007; 54(79):2078-83. · 0.77 Impact Factor
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    ABSTRACT: Previous studies have shown small intestinal submucosa (SIS) can be used as biodegradable scaffolds in tissue engineering small intestine. The purpose of this study is to evaluate the regeneration of neointestine and its morphology using SIS. A 2-cm tubular SIS graft from Sprague Dawley rat donors was interposed in the middle of a 6-cm ileal Thiry-Vella loop of Lewis rats, which was used to construct an ileostomy. The grafts were harvested at each of the time points ranging from 2 weeks to half a year after implantation, and native small intestine and grafts were investigated for morphology using histology and immunohistochemistry. At the early postoperative period, SIS grafts were colonized by numerous inflammatory cells. A mucosal epithelial layer began to line the luminal surface of the graft by 4 weeks, and by 12 weeks, the luminal surface was covered completely by a layer of neomucosa. Neomucosa with typical small bowel morphology was characterized by a columnar epithelial cell layer with goblet cells, Paneth cells, absorptive enterocytes, and enteroendocrine cells. Significant differences between neomucosa by 12 weeks and 24 weeks in the measurements of mucosal thickness, villus height, and crypt depth were found. The outer walls of SIS grafts were composed of distinct bundles of well-formed smooth muscle-like cells with some fibrovascular tissue. This initial study suggests that tissue engineering neointestine using SIS can develop structural features of the normal intestine. Small intestinal submucosa might be a viable material in the creation of neointestine for patients suffering short bowel syndrome.
    Journal of Pediatric Surgery 01/2006; 40(12):1898-902. · 1.38 Impact Factor