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Objective To investigate the effect of miR-17-5p expression on the injury of human lung adenocarcinoma alveolar basal epithelial cell line A549 induced by Streptococcus pneumonia and its mechanism. Methods A549 cells was divided into control group,infected group(1×108 CFU/mL S.pneumoniae),anti-miR-17-5p intervention group (transfected with anti-miR-17-5p before S.pneumoniae infection),anti-miR-NC intervention group (transfected with anti-miR-NC before S.pneumoniae infection), and pcDNA-ALDH2 intervention group(trans- fected with pcDNA-ALDH2 before S.pneumoniae infection),and pcDNA intervention group (transfected with pcDNA before S.pneumoniae infection).The level of miR-17-5p and ALDH2 mRNA was detected by RT-qPCR. IL-6 and IL-10 in cell culture supernatant were detected by enzyme-linked immunosorbent assay. Apoptosis was detected by flow cytometry. ALDH2, Bcl-2 and Bax protein were detected by Western blot. Dual luciferase assay verified the targeting relationship between miR-17-5p and ALDH2. Results Compared with the control group, the level of miR-17-5p in the infected group was significantly increased (P＜0.05), while mRNA and the protein concentration of ALDH2, IL-10 and Bcl-2 were significantly decreased (P＜0.05). However, apoptotic rate and the levels of IL-6 and Bax were significantly increased (P＜0.05). Compared with the infected+anti-miR-NC group, IL-10 and Bcl-2 in the infected+anti-miR-17-5p group were significantly increased(P＜0.05), the apoptotic rate, IL-6 and Bax were significantly decreased (P＜0.05). Compared with the infected+pcDNA group, the levels of IL-10 and Bcl-2 in the infected+pcDNA-ALDH2 group were significantly increased (P＜0.05), and the apoptotic rate and the levels of IL-6 and Bax were significantly decreased (P＜0.05).miR-17-5p negatively regulated ALDH2 expression.Inhibition of ALDH2 expression reversed the effect of inhibiting miR-17-5p expression on S.pneumoniae-induced A549 cells damage. Conclusions Inhibition of miR-17-5p expression reduces S.pneumoniae-induced the damage of the cell line A549 by regulating ALDH2.

Dark microbial CO2 fixation plays a crucial role in soil organic carbon (SOC) sequestration, but the fungus contributions to this process in varying agroecosystems remain unclear. This study investigated fungal CO2 fixation in 29 soil samples collected from the major agricultural regions across China. Phospholipid fatty analysis-stable isotope probing revealed variations in fungal fixation by 2.2 to 65.5% of the total microbial CO2 fixation. CO2 assimilation of ten fungal strains belonging to the phyla Ascomycota and Basidiomycota was determined in three different media using an isotope labeling experiment. Trichocladium uniseriatum had the highest CO2 fixation capacity. T. uniseriatum had the reductive tricarboxylic acid cycle (rTCA) for CO2 assimilation associated with sulfite metabolism. T. uniseriatum was thus selected for use in soil inoculation experiments, aimed to trace the fractionation of its fixed carbon in SOC. The CO2 fixation rate of T. uniseriatum was 0.07–0.09 μg C per g of soil per day. Notably, 77–82% of the fixed C was partitioned into the mineral-associated soil organic carbon. This study highlights the significance of fungal CO2 fixation in soil carbon sequestration. [ABSTRACT FROM AUTHOR]

The Yangtze Platform preserves relatively thick carbonate successions and excellent fossil records across the Ediacaran-Cambrian boundary interval. The intensely studied Meishucun section in East Yunnan was one of the Global Stratotype Section candidates for the Precambrian-Cambrian boundary. However, depositional breaks were suspected in the section and the first appearance of small shelly fossils could not be verified. The Laolin section located in NE Yunnan is more continuous and shows great potential for global correlation of carbon isotope features across the Precambrian-Cambrian boundary. However, the stratigraphic framework and correlations were controversial. We studied and systematically sampled the Laolin section and present here new carbon isotope data for this section. The Laolin section consists of, in ascending order, the Baiyanshao dolostone of the Dengying Formation, the Daibu siliceous dolostone, Zhongyicun dolomitic phosphorite, lower Dahai dolostone and upper Dahai limestone of the Zhujiaqing Formation, and the black siltstone of the Shiyantou Formation. Our data reveal a large negative [delta][sup.13]C excursion (-7.2 [per thousand], L1') in the Daibu Member, which matches the previously published data for the Laolin section, and a large positive excursion (+3.5 [per thousand], L4) in the Dahai Member, which was not shown in the published data. The excursion Ll' correlates well with the similarly large negative excursion near the first appearance of small shelly fossils in Siberia and Mongolia. Similar magnitude excursions are also known from Morocco and Oman, for which there are no robust fossil constraints but from where volcanic ash beds have been dated precisely at 542 Ma, thus confirming a global biogeochemical event near the Ediacaran-Cambrian boundary. Our data also indicate that deposition was more continuous at the Laolin section compared with the Meishucun section, where there are no records of a comparable negative excursion near the Ediacaran-Cambrian boundary, nor any comparable positive excursion in the Dahai Member. Therefore, the Laolin section has proven potential to be a supplementary Global Stratotype Section for the Ediacaran-Cambrian boundary on the Yangtze Platform. Keywords: C-isotope stratigraphy, Ediacaran-Cambrian boundary, Laolin section, Yangtze Platform.

The Shimian Neoproterozoic plutons are located on the western margin of the Yangtze Block and are important for reconstructing the tectonic environment of this region. We present in situ zircon LA–ICP–MS U–Pb geochronological and Hf isotopic analyses for the plutons, as well as whole‐rock major‐ and trace‐element compositions. The monzogranite and syenogranite yield concordant ages of 773.6 ± 5.6 Ma and 812.2 ± 1.8 Ma, respectively, which indicates that they formed during the Tonian of the Neoproterozoic. The samples have very similar geochemistry, with high SiO2 (71.45–75.46 wt%) and Al2O3 (12.38–14.36 wt%) contents. The samples have a geochemical characteristics typical of peraluminous A‐type granites, including high Ga/Al and Rb/Sr ratios and elevated contents of high‐field‐strength elements. The samples also display high Rb/Sr (13.9–23.0) and Rb/Nb (12.5–19.2) ratios. The monzogranite and syenogranite yield positive εHf(t) values (+1.6 to +9.4 and + 5.2 to +9.8, respectively) and T2DM ages of 1.54–1.22 Ga and 1.51–1.21 Ga, respectively, which indicates that they were derived from partial melting of Mesoproterozoic crust or contamination with upper mantle. We propose that the syenogranite and monzogranite formed in a syn‐orogenic extensional setting during the Tonian period and that continuous subduction was responsible for the Neoproterozoic magmatic activities. [ABSTRACT FROM AUTHOR]

Objective: To study the effect of gamma linolenic acid (GLA) on atherogenesis in rats., Method: Sixty healthy male rats were randomly divided into 6 groups: normal contro 1, fed by normal feed; atherogenesis mode 1, fed by high lipid diet; positive control group 0.9 mg x kg(-1) x d(-1) of lovastatin and group IV 250 mg x kg(-1) x d(-1) duoxikang; high dose of 375 mg x kg(-1) x d(-1) GLA; low dose of 187.5 mg x kg(-1) x d(-1) GLA. After the model group received atherogenic diet for six weeks, serum triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) were detected by enzyme method to confirm the formation of atherogenic. After fed for another five weeks, morphologic atherosclerosis of aorta in rats was observed by HE staining methods. The blood samples were collected and serum TC, TG, HDL-C, LDL-C, T-AOC, HL, LPL, NO, NOS, MDA and GSH were determined., Result: GLA attenuated the formation of atherosclerotic plaques, inhibited the level of serum TC, TG, MDA, OX-LDL, NO, NOS, HL, LPL and LDL-C and increased the level of T-AOC., Conclusion: GLA might significantly attenuate the development of atherosclerosis in rats fed with high lipid diet through improving the antioxidation capacity of the body.