RNA-Seq for Gene Expression Profiling of Human Necrotizing Enterocolitis: a Pilot Study

Necrotizing enterocolitis (NEC) characterized by inflammatory intestinal necrosis is a major cause of mortality and morbidity in newborns. Deep RNA sequencing (RNA-Seq) has recently emerged as a powerful technology enabling better quantification of gene expression than microarrays with a lower background signal. A total of 10 transcriptomes from 5 pairs of NEC lesions and adjacent normal tissues obtained from preterm infants with NEC were analyzed. As a result, a total of 65 genes (57 down-regulated and 8 up-regulated) revealed significantly different expression levels in the NEC lesion compared to the adjacent normal region, based on a significance at fold change ≥ 1.5 and P ≤ 0.05. The most significant gene, DPF3 (P < 0.001), has recently been reported to have differential expressions in colon segments. Our gene ontology analysis between NEC lesion and adjacent normal tissues showed that down-regulated genes were included in nervous system development with the most significance (P = 9.3 × 10⁻⁷; P(corr) = 0.0003). In further pathway analysis using Pathway Express based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, genes involved in thyroid cancer and axon guidance were predicted to be associated with different expression (P(corr) = 0.008 and 0.020, respectively). Although further replications using a larger sample size and functional evaluations are needed, our results suggest that altered gene expression and the genes' involved functional pathways and categories may provide insight into NEC development and aid in future research.

The Evaluation of Preoperative Oral Carbohydrate-Rich Solution Effects on Insulin Resistance in Patients undergoing Colectomy

PURPOSE: Reducing preoperative fasting time showed positive effects in several studies, and current guidelines suggest use of a preoperative oral carbohydrate-rich solution before elective surgeries. For elective colectomy procedures, some surgeons favor two-day bowel preparation with diet restriction and administration of laxatives. Aside from patients experiencing the discomfort of nil per os (NPO), there are reported benefits regarding intake of liquids until at least two hours prior to surgery, including decrease in insulin resistance, without additional postoperative surgical complications. The aim of this study is to show the benefits of administration of oral rehydration solution (ORS) two hours prior to surgery for patients undergoing elective colectomy, particularly postoperative insulin resistance. METHODS: This is a randomized controlled trial. All patients undergoing elective colectomy were included and randomized to the control arm or treatment arm. The control arm consisted of the standard bowel preparation and one day of NPO, while the treatment arm consisted of the standard bowel preparation and allowing intake of carbohydrate-rich ORS until 2 hours before surgery. The insulin, glucose, cortisol, and triglyceride levels were determined immediately after induction, 6 hours, 24 hours, and 48 hours post-op, and compared. The homeostatic model assessment-insulin resistance, insulin, glucose, cortisol, and triglyceride levels were determined and compared between the two groups. Anxiety and postoperative complications were monitored and assessed as well. RESULTS: There was less insulin resistance in patients who received ORS 2 hours prior to surgery. Insulin, glucose, cortisol, and triglyceride levels were lower in the treatment group compared to the control group. Taking ORS 1 day prior and until 2 hours before surgery decreased anxiety and discomfort, and alleviated hunger. CONCLUSION: Regarding complications, there was no difference in the incidence of aspiration and postoperative complications. There were fewer wound complications and incidence of paralytic ileus in the treatment group.