[Collaborative monitoring network of ecologically fragile areas in China and its application in carrying capacity research]. / ä¸­å›½ç”Ÿæ€è„†å¼±åŒºè”ç½‘ååŒè§‚æµ‹åŠå ¶åœ¨æ‰¿è½½åŠ›ç ”ç©¶ä¸­çš„åº”ç”¨.

Ecologically fragile areas account for more than 60% of land area in China. Global change and human activities are aggravating ecosystem degradation and reducing the carrying capacity of resources and environment. It is important to accurately quantify the carrying capacity of resources and environment in ecologically fragile areas to deal with the risk and challenge of global change and to speed up the construction of ecological civilization. How-ever, existing methods evaluating carrying capacity of resources and environment are difficult to reflect the transmission effect of ecosystem structures, processes and functions changes among resource, environment and carrying capacity. Therefore, it is essential to establish a field observation network and obtain the comprehensive data set of resource and environment elements-ecosystem structure, function and process-ecosystem carrying capacity for develo-ping the theory and evaluation method. We introduced the collaborative monitoring networks of flux and UAV photographing, including the thoughts, practice, and preliminary results in the study of ecosystem structure, process and function in the fragile ecosystems of China. Based on the achievements and progress, we proposed the application of collaborative monitoring networks in capacity evaluation.

Short-chain fatty acids inhibit growth hormone and prolactin gene transcription via cAMP/PKA/CREB signaling pathway in dairy cow anterior pituitary cells.

Short-chain fatty acids (SCFAs) play a key role in altering carbohydrate and lipid metabolism, influence endocrine pancreas activity, and as a precursor of ruminant milk fat. However, the effect and detailed mechanisms by which SCFAs mediate bovine growth hormone (GH) and prolactin (PRL) gene transcription remain unclear. In this study, we detected the effects of SCFAs (acetate, propionate, and butyrate) on the activity of the cAMP/PKA/CREB signaling pathway, GH, PRL, and Pit-1 gene transcription in dairy cow anterior pituitary cells (DCAPCs). The results showed that SCFAs decreased intracellular cAMP levels and a subsequent reduction in PKA activity. Inhibition of PKA activity decreased CREB phosphorylation, thereby inhibiting GH and PRL gene transcription. Furthermore, PTX blocked SCFAs- inhibited cAMP/PKA/CREB signaling pathway. These data showed that the inhibition of GH and PRL gene transcription induced by SCFAs is mediated by Gi activation and that propionate is more potent than acetate and butyrate in inhibiting GH and PRL gene transcription. In conclusion, this study identifies a biochemical mechanism for the regulation of SCFAs on bovine GH and PRL gene transcription in DCAPCs, which may serve as one of the factors that regulate pituitary function in accordance with dietary intake.

Expression of interleukin 6 in brain and colon of rats with TNBS-induced colitis.

AIM: To characterise expression of interleukin 6 (IL-6), a potent proinflammatory cytokine, in the occurrence and development of inflammatory bowel disease (IBD) and investigate its effect on neuroimmunomodulation and immune homeostasis regulation. METHODS: In this study, rats with colitis induced by trinitrobenzene sulfonic acid (TNBS) were sacrificed on days 3, 7, 14, 21 and 28 after induction. In the controls, the TNBS was just replaced by equivalent amount of phosphate buffered solution (PBS, 0.01 mol/L). IL-6 mRNA expression in brain and colon tissues in each phase was evaluated by real-time reverse transcription-polymerase chain reaction, and cellular localisation and protein level of IL-6 was determined by immunohistochemistry. RESULTS: At day 7, mRNA expression of IL-6 was significantly higher in the colon and brain of IBD rats than that of the controls. The protein level was also significantly higher in colon, hypothalamus and cerebral cortex of IBD rats compared with the controls. So there are similar temporal trends in IL-6 mRNA expression and protein levels in all positions with a persistent increase to a peak at day 7, followed by a decline and gradual return to normal levels. CONCLUSION: These results revealed that changes in IL-6 expression in brain and colon tissues occur in different phases of IBD. Therefore, we propose that the nerve centre regulates and controls the occurrence and development of IBD via IL-6.

[Study on screening differentially expressed genes in mice livers by silver staining DD-PCR].

AIM: To screen swimming-fatigue related genes in mice and lay theoretic basis for researching the molecular mechanism of fatigue. METHODS: 30 male BALB/c mice (20 +/- 2g) were divided into control group, dipping in water group and swimming-fatigue group respectively. After fatigue for swimming in swimming-fatigue group, with control group and dipping in water group, liver tissues in mice were collected. With improved silver staining mRNA differential display method, the differentially expressed genes in mice livers were screened and evaluated by reversed Northern blot. The positive segments were analyzed homology by BLAST. RESULTS: 7 of DD-ESTs were gained. Two of them only expressed in swimming-fatigue group, two down-regulated expressed, and three up-regulated. One of them was a novel gene and was accepted by GenBank, AY615302. CONCLUSION: Seven DD-ESTs in swimming-fatigue mice were gained by silver staining mRNA differential display method.