ABSTRACT
BACKGROUND: Intensification of agricultural systems may result in overexploitation of water resources in arid regions because enhanced productivity of crops is often associated with increased actual evapotranspiration (AET). The aim of this study was to quantify the effect of increased regional AET on the groundwater level in a case study of the oasis located within the Shiyang River Basin near the edge of the Gobi Desert. RESULT: The results of the study show that regional AET increased during the period from 1981 to 2010 due to increasing oasis area and air temperature. The water losses due to AET exceeded the water supply from the mountainous discharges of the basin by the end of this period, leading to groundwater overexploitation in the oasis area. CONCLUSIONS: This case study shows the importance of considering the effect of climate change on water losses associated with increasing agricultural production for the sustainable agricultural development of arid regions.
ABSTRACT
BACKGROUND:The Wnt/β-catenin signaling pathway is one of the most important signaling pathways in stem cel regulation, which is involved in regulation of cel proliferation and differentiation. OBJECTIVE:To investigate the expression of Wnt/β-catenin main signaling molecule in inflammatory bowel tissues treated with bone marrow mesenchymal stem cel transplantation. METHODS:2,4,6-Trinitrobenzene sulfonic acid was used for establishing inflammatory bowel diseases rat models. Bone marrow mesenchymal stem cels labeled with green fluorescent protein were transplanted into rat modelsviatail vein. Normal saline was injected as control. The expression of Wnt/β-catenin signaling molecule was detected in the large intestine tissue of inflammatory bowel disease rat models by quantitative RT-PCR at 14 and 28 days after transplantation. RESULTS AND CONCLUSION:Real-time quantitative PCR results showed that the expression of Wnt3a andβ-catenin in the inflammatory bowel tissue increased significantly (P 0.05). The expressions of Wnt3a, β-catenin and c-myc in the transplantation group were significantly lower than those in the control group after transplantation (P <0.05). These findings indicate that the Wnt/β-catenin signaling pathway plays important roles in inflammatory bowel disease and repair after bone marrow mesenchymal stem cel transplantation, while this pathway may promote stem cels differentiating into intestinal epithelium, promote recovery from inflammatory bowel disease, repair inflammatory area, and restore intestinal tissue homeostasis.
