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Purpose The enteric microbiome is known to play a major role in healthy gut homeostasis and several disease states. It may also contribute to both the intestinal recovery and complications that occur in patients with short bowel syndrome. The extent and nature of alterations to the gut microbiota following intestinal resection, however, are not well studied in a controlled setting. The purpose of this investigation is to characterize the effects of massive small bowel resection on the murine enteric microflora. Methods Wild-type C57BL6 mice, following a week of acclamation to a liquid rodent diet, underwent either 50 % proximal small bowel resection (SBR) or a sham operation. Mice were sacrificed, and enteric contents from the small bowel, cecum, and stool were harvested at 7 and 90 days post-operatively. DNA was isolated, and the V3–V5 regions of the 16s rRNA gene amplified and pyrosequenced on a Roche 454 platform. Sequences were clustered into operation taxonomic units and classified. Communities were then analyzed for diversity and phylogenic composition. Results In the long-term group, the microbes inhabiting the ileum of mice undergoing SBR and sham operation differed significantly at the genus level (p<0.001). Small bowel contents collected before and after SBR also differed significantly (p= 0.006). This was driven by an increase in Lactobacillus and decrease in Enterobacteriaceae species in mice undergoing SBR. No difference was seen in the long-term stool or in stool, cecal, or ileal contents in the short-term. No difference in microbial community diversity was found in any group. Conclusion Bowel resection induces long-term changes in the microbial community of the murine ileum, but not at more distal sites of the gastrointestinal tract. The increase in Lactobacillus encountered small bowel of resected mice correlates with limited previous studies. These changes may reflect an adaptive response of the microbiota to maximize energy extraction, but further studies are needed to establish the role played by this altered community.

Necrotizing enterocolitis (NEC) is a devastating condition of premature infants that results from the gut microbiome invading immature intestinal tissues. This results in a life-threatening disease that is frequently treated with the surgical removal of diseased and dead tissues. Epidermal growth factor (EGF), typically found in bodily fluids, such as amniotic fluid, salvia and mother’s breast milk, is an intestinotrophic growth factor and may reduce the onset of NEC in premature infants. We have produced human EGF in soybean seeds to levels biologically relevant and demonstrated its comparable activity to commercially available EGF. Transgenic soybean seeds expressing a seed-specific codon optimized gene encoding of the human EGF protein with an added ER signal tag at the N’ terminal were produced. Seven independent lines were grown to homozygous and found to accumulate a range of 6.7 +/- 3.1 to 129.0 +/- 36.7 μg EGF/g of dry soybean seed. Proteomic and immunoblot analysis indicates that the inserted EGF is the same as the human EGF protein. Phosphorylation and immunohistochemical assays on the EGF receptor in HeLa cells indicate the EGF protein produced in soybean seed is bioactive and comparable to commercially available human EGF. This work demonstrates the feasibility of using soybean seeds as a biofactory to produce therapeutic agents in a soymilk delivery platform.

Previous studies have shown that high-fat diet (HFD) enhances adaptation if provided immediately following small bowel resection (SBR). The purpose of this study was to determine if HFD could further enhance villus growth after resection-induced adaptation had already taken place. C57/Bl6 mice underwent a 50 % proximal SBR or sham operation and were then provided a standard rodent liquid diet (LD) ad lib. After a typical period of adaptation (7 days), SBR and sham-operated mice were randomized to receive either LD or HFD (42 % kcal fat) for an additional 7 days. Mice were then harvested, and small intestine was collected for analysis. Adaptation occurred in both SBR groups; however, the SBR/HFD had significantly increased villus height compared to SBR/LD. Reverse transcription–polymerase chain reaction of villus enterocytes showed a marked increase in CD36 expression in the SBR/HFD group compared with SBR/LD mice. While exposure to increased enteral fat alone did not affect villus morphology in sham-operated mice, HFD significantly increased villus growth in the setting of resection-induced adaptation, supporting the clinical utility of enteral fat in augmenting adaptation. Increased expression of CD36 suggests a possible mechanistic role in dietary fat metabolism and villus growth in the setting of short gut syndrome.

Background & AimsIntestinal adaptation is a compensatory response to the massive loss of small intestine after surgical resection. We investigated the role of intestinal epithelial cell–specific mammalian target of rapamycin complex 1 (i-mTORC1) in intestinal adaptation after massive small bowel resection (SBR).MethodsWe performed 50% proximal SBR on mice to study adaptation. To manipulate i-mTORC1 activity, Villin-CreER transgenic mice were crossed with tuberous sclerosis complex (TSC)1flox/flox or Raptorflox/flox mice to inducibly activate or inactivate i-mTORC1 activity with tamoxifen. Western blot was used to confirm the activity of mTORC1. Crypt depth and villus height were measured to score adaptation. Immunohistochemistry was used to investigate differentiation and rates of crypt proliferation.ResultsAfter SBR, mice treated with systemic rapamycin showed diminished structural adaptation, blunted crypt cell proliferation, and significant body weight loss. Activating i-mTORC1 via TSC1 deletion induced larger hyperproliferative crypts and disorganized Paneth cells without a significant change in villus height. After SBR, ablating TSC1 in intestinal epithelium induced a robust villus growth with much stronger crypt cell proliferation, but similar body weight recovery. Acute inactivation of i-mTORC1 through deletion of Raptor did not change crypt cell proliferation or mucosa structure, but significantly reduced lysozyme/matrix metalloproteinase-7–positive Paneth cell and goblet cell numbers, with increased enteroendocrine cells. Surprisingly, ablation of intestinal epithelial cell–specific Raptor after SBR did not affect adaptation or crypt proliferation, but dramatically reduced body weight recovery after surgery.ConclusionsSystemic, but not intestinal-specific, mTORC1 is important for normal adaptation responses to SBR. Although not required, forced enterocyte mTORC1 signaling after resection causes an enhanced adaptive response.

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Background Specific data are needed regarding the impact of transfusion on operative complications in pancreatectomy. The objectives of this study were to determine risk factors for transfusion and to evaluate the potential association between transfusion and operative complications in elective pancreatectomy procedures. Study Design We reviewed our institution’s pancreatectomy and ACS-NSQIP databases. Multivariate analysis was used to determine clinicopathologic risk factors predictive of transfusion, and then a transfusion propensity score was developed to evaluate the impact of transfusion on post-pancreatectomy complications. Results Of the 173 patients who were treated from September 2007 to September 2011, 78 patients (45 %) were transfused≥1 unit of blood (median, 3.0 units; range, 1–55). Risk factors for transfusion included increasing Body Mass Index (BMI), smoking, increasing mortality risk score, preoperative anemia, intraoperative blood loss, and benign pathology. After controlling for these risk factors using a transfusion propensity score, transfusion was an independent predictor of increased complications, infectious complications, and hospital costs. Conclusions Multiple factors are predictive of transfusion in pancreatectomy, including increasing BMI and smoking. When controlling for transfusion propensity based on these risk factors, RBC transfusion is associated with worse operative outcomes including infectious complications. Development of protocols and strategies to minimize unnecessary transfusion in pancreatectomy are justified.

What are the novel findings of this work? Among fetuses with twin-twin transfusion syndrome (TTTS) treated with fetoscopic laser photocoagulation, those with later gestational age (GA) at the time of laser surgery, earlier GA at delivery and lower birth weight were found to be at increased risk of developing neurodevelopmental impairment (NDI) in early childhood. However, no significant association was found between Quintero stage of TTTS and risk of NDI. What are the clinical implications of this work?Clarification of the perinatal risk factors of NDI can be useful in clinical practice for parental counseling and identification of TTTS survivors at risk of developing NDI in future life.