Progress in intestinal adaptation after enterectomy / 中华胃肠外科杂志

Intestinal adaptation is a spontaneous compensation of the remanent bowel after extensive enterectomy, which improves the absorption capacity of the remanent bowel to energy, fluid and other nutrients. Intestinal adaptation mainly occurs within 2 years after enterectomy, including morphological changes, hyperfunction and hyperphagia. Intestinal adaptation is the key factor for patients with short bowel syndrome to weaning off parenteral nutrition dependence and mainly influenced by length of remanent bowel, type of surgery and colon continuity. In addition, multiple factors including enteral feeding, glucagon-like peptide 2 (GLP-2), growth hormone, gut microbiota and its metabolites regulate intestinal adaptation via multi-biological pathways, such as proliferation and differentiation of stem cell, apoptosis, angiogenesis, nutrients transport related protein expression, gut endocrine etc. Phase III clinical trials have verified the safety and efficacy of teduglutide (long-acting GLP-2) and somatropin (recombinant human growth hormone) in improving intestinal adaptation, and both have been approved for clinical use. We aim to review the current knowledge about characteristics, mechanism, evaluation methods, key factors, clinical strategies of intestinal adaptation.

Effect of aging on bioavailability of copper on the fluvo aquic soil

The bioavailability of copper in contaminated soils has received more attention due to the safety concern of food chain. The bioavailability of metals is determined by its fractions which are affected by the soil properties and its aging time. This paper focused on the aging effect on the bioavailability of copper added to the soil. The garden soil [fluvo aquic soil] was treated with 100mg/kg and 1000 mg/kg of CuSO4 and incubated for 14, 21, 28, 42, 63, 120, 200, 300 and 400 days in the laboratory respectively. The sequential extraction procedure was used to characterize copper bioavailability in the soil. Meanwhile, the barley was cultured on the same soil incubated and its toxicity was assessed according to the guideline of International Organization for Standardization. The findings show that the exchangeable and carbonate-bound copper decreased with the aging time after addition of CuSO4 in to soil. Meanwhile, the percentages of Fe-Mn oxides and organic bound copper increased. The residual copper was changed little during the aging course. The copper fractions became stable in soils after 60 days. The kinetic equations showed that the Power function and the Elovich equation were fitted well to the experimental data, and the r2 values ranged from 0.840 to 0.982 and 0.741 to 0.975 respectively. The barley test showed that the barley root length was more sensitive to reflect copper toxicity than the shoot biomass. And the exchangeable and carbonate-bound copper were significantly correlated with the barley root length