Progress and research direction of normal-pressure shale gas exploration and development in southeastern Chongqing

There are high-pressure shale gas reservoirs and normal-pressure shale gas reservoirs in the Sichuan Basin and its periphery. In recent years, SINOPEC East China Oil & Gas Company takes technical research for normal-pressure shale gas in the complex tectonic regions of basin margin and the fold belt outside Sichuan Basin in southeastern Chongqing, makes significant progress in exploration and development of normal-pressure shale gas, and forms relatively perfect geological theory and technology series of normal-pressure shale gas after more than ten years of research. The normal-pressure shale gas has the characteristics of complex structure, very different preservation condition, and complex in-situ stress compared with high-pressure shale gas. The exploration and development progress and cognition of normal-pressure shale gas in southeastern Chongqing are systematically summarized from geological characteristics, enrichment laws and exploration and development efficiency: (1)The continental shelf facies in deep-water shelf controls the high-quality shale distribution of normal-pressure shale gas, the multistage tectonism controls the differential distribution of tectonic types, fractures and in-situ stress, and the preservation condition becomes better from east to west and from south to north; (2)Four accumulation-dispersion modes of normal-pressure shale gas were established to guide exploration deployment. In the basin margin area, three 100 billion cubic meters increasing reserves zones of Pingqiao, Dongsheng and Yangchungou were completed in the basin margin, and Nanchuan normal-pressure shale gas field was found. In the basin outside area, some favorable exploration targets were confirmed, such as Wulong Syncline, Daozhen Syncline, and Laochangping Anticline; (3)The development technology policy of normal-pressure shale gas was formulated, controlling factors of productivity were defined, and benefit development was realized.Through systematic summary of previous achievement understanding, exploration and development experience, the challenge was analyzed, and the research direction was cleared, to provide reference for normal-pressure shale gas benefit development in similar areas of South China

Didymin Alleviates Hepatic Fibrosis Through Inhibiting ERK and PI3K/Akt Pathways via Regulation of Raf Kinase Inhibitor Protein

Background: Didymin has been reported to have anti-cancer potential. However, the effect of didymin on liver fibrosis remains illdefined. Methods: Hepatic fibrosis was induced by CCl4 in rats. The effects of didymin on liver pathology and collagen accumulation were observed by hematoxylin-eosin and Masson's trichrome staining, respectively. Serum transaminases activities and collagen-related indicators levels were determined by commercially available kits. Moreover, the effects of didymin on hepatic stellate cell apoptosis and cell cycle were analyzed by flow cytometry. Mitochondrial membrane potential was detected by using rhodamine-123 dye. The expression of Raf kinase inhibitor protein (RKIP) and the phosphorylation of the ERK/MAPK and PI3K/Akt pathways were assessed by Western blot. Results: Didymin significantly ameliorated chronic liver injury and collagen deposition. It strongly inhibited hepatic stellate cells proliferation, induced apoptosis and caused cell cycle arrest in G2/M phase. Moreover, didymin notably attenuated mitochondrial membrane potential, accompanied by release of cytochrome C. Didymin significantly inhibited the ERK/MAPK and PI3K/Akt pathways. The effects of didymin on the collagen accumulation in rats and on the biological behaviors of hepatic stellate cells were largely abolished by the specific RKIP inhibitor locostatin. Conclusion: Didymin alleviates hepatic fibrosis by inhibiting ERK/MAPK and PI3K/Akt pathways via regulation of RKIP expression

Raf Kinase Inhibitory Protein Down-Expression Exacerbates Hepatic Fibrosis In Vivo and In Vitro

Background/Aims: Raf kinase inhibitory protein (RKIP) is closely associated with numerous tumors and participates in their development through regulating the growth, apoptosis, invasion and metastasis of tumor cells. However, the role of RKIP in chronic liver injury and particularly in liver fibrosis is still unclear. Methods: In the present study, hepatic fibrosis was induced by porcine serum (PS) in rats and primary hepatic stellate cells (HSCs) were isolated from rat livers. Moreover, locostatin was used to interfere with RKIP expression. Results: RKIP expression was significantly inhibited by locostatin in both liver tissues of rats and primary HSCs. Down-regulating RKIP expression resulted in serious liver injury, extensive accumulation of collagen, and significant increase in the levels of ALT, AST and TNF-α during liver fibrosis in rats. Moreover, down-regulating RKIP significantly promoted HSCs proliferation and colony formation in vitro. Reduced RKIP significantly increased the production of collagen and the level of α-SMA as well as the expression of MMP-1 and MMP-2 in both liver tissues and primary HSCs. Furthermore, down-regulating RKIP promoted the activation of the ERK and TLR4 signaling pathways. Conclusion: Our findings clearly indicate an inverse correlation between RKIP level and the degree of the liver injury and fibrosis. The decrease in RKIP expression may exacerbate chronic liver injury and liver fibrosis

Trolline Ameliorates Liver Fibrosis by Inhibiting the NF-κB Pathway, Promoting HSC Apoptosis and Suppressing Autophagy

Background/Aims: Previous studies have shown that trolline possesses various forms of pharmacological activity, including antibacterial and antiviral potency. The present paper addressed the putative hepatoprotective effects of trolline. Methods: Rats received 2 ml/kg CCl4 (mixed 1: 1 in peanut oil) intragastrically twice a week for 8 weeks to induce hepatic fibrosis. The animals were then treated with trolline for additional 4 weeks. Liver pathology and collagen accumulation were observed by hematoxylin-eosin and Masson’s trichrome staining, respectively. Serum transaminase activity and collagen-related indicator level were determined by commercially available kits. NF-κB pathway activation was also examined. Moreover, the effects of trolline on hepatic stellate cell (HSC-T6) apoptosis, mitochondrial membrane potential (MMP), and autophagy were assessed. Results: Trolline significantly alleviated CCl4-induced liver injury and notably reduced the accumulation of collagen in liver tissues. Trolline treatment also markedly decreased inflammatory cytokines levels by inhibiting the NF-κB pathway. Trolline strongly inhibited HSC-T6 activation and notably induced cell apoptosis by modulating the Bax/Bcl-2 ratio, caspase activity, and MMP. Moreover, trolline significantly inhibited HSC-T6 autophagy, as evidenced by the decrease in the formation of autophagic vacuoles and the number of autophagosomes, by regulating the expression levles of LC3, Beclin-1, P62, Atg 5 and 7. Conclusion: Our study demonstrates that trolline ameliorates liver fibrosis, possibly by inhibiting the NF-κB pathway, promoting HSCs apoptosis and suppressing autophagy

High-Sensitivity Determination of K, Ca, Na, and Mg in Salt Mines Samples by Atomic Emission Spectrometry with a Miniaturized Liquid Cathode Glow Discharge

An atomic emission spectrometer (AES) based on a novel atmospheric pressure liquid cathode glow discharge (LCGD) as one of the most promising miniaturized excitation sources has been developed, in which the glow discharge is produced between a needle-like Pt anode and the electrolyte (as cathode) overflowing from a quartz capillary. Lower energy consumption (<50 W) and higher excitation efficiency can be realized by point discharge of the needle-like Pt. The miniaturized LCGD seems particularly well suited to rapid and high-sensitivity determination of K, Ca, Na, and Mg in salt mines samples. The optimized analytical conditions of LCGD-AES were pH = 1 with HNO3 as electrolyte, 650 V discharge voltage, and 3 mL min−1 solution flow rate. The limits of detections (LODs) of K, Ca, Na, and Mg were 0.390, 0.054, 0.048, and 0.032 mg L−1, respectively. Measurement results of the LCGD-AES are in good agreement with the comparison value obtained by inductively coupled plasma (ICP) and ion chromatography (IC). All results suggested that the developed portable analytical instrument can be used for on-site and real-time monitoring of metal elements in field with further improvement