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Background and objective Previous studies have found the lincRNAs play important roles in the occurrence and development of lung adenocarcinoma, but their regulated mechanims are still unclear. The aim of this study is to evaluate the relationship between DNA methylation and lincRNA expression, and the effect of prognosis in lung adenocarcinoma. Methods The whole genome Illumina Methylation 450 DNA methylatiuon data and RNAseq for lung adenocarcinoma were download from TCGA. DNA methylation around lincRNA and their relationship to gene expression were analyzed. Their contribution to lung adenocarcinoma were further analyzed by comparing DNA methylation and lincRNA expression in tumor and adjacent tissues. Results The methylation level in promoter region was lower than other positions in lincRNA, and was negatively correlated with gene expression. There were 427 lincRNA genes showed differential DNA methylation in their promoter regions in tumor and adjacent tissues. Among these, 15 lincRNA genes showed differential gene expression and negatively correlated with DNA methylation, including FENDRR (a tumor progression and metastasis gene) whose high methylation in its promoter showed poor survival in lung adenocarcinoma. Conclusion The expression of lincRNA can be regulated by DNA methylation in their promoter regions, and the level of DNA methylation is related to patient prognosis in lung adenocarcinoma.

Background and objective To detect the expression of neutrophil gelatinase-assoeiated lipocalin (NGAL) in the different differentiations of lung cancer tissues and to study the mechanism of invasion of A549 cells affected by NGAL. Methods The expression of NGAL was detected by immunochemistry in lung cancer tissue and the tissue around edge of the cancer. The effect of NGAL expression on A549 cells was observed by using qRT-PCR and Western blot. The abilities of invasion and metastasis were evaluated by transwell invasion and migration assay, and cell scratch assay in vitro. The protein expression of E-cadherin, Vimentin was measured by immunofluoresence and Western blot. Results The positive expression rate of NGAL was 76.32% (58/76) in the lung cancer, 13.3% (4/30) in adjacent tissue by immunochemistry. NGAL expression levels in the lung cancer tissues were significantly higher than that in adjacent tissues. The rate of migration and invasion in NGAL-siRNA group was 60.4%±6.4% compared to 50.5%±4.4% in the control group, there was a significant difference (P

The Lower Silurian Longmaxi Formation on the southwestern margin of the Sichuan Basin holds significant shale gas reserves. The characteristics and formation stages of fractures play a crucial role in shale gas accumulation and productivity. Focusing on the Longmaxi Formation in the Tiangongtang area, this study employed core analysis, FMI (Formation Micro-Imager) logging, rock acoustic emission experiments, carbon-oxygen isotope analysis of fracture fillings, fluid inclusion homogenization temperature testing, and burial-thermal evolution history analysis to investigate the development characteristics and formation periods of natural fractures in the shale. The results indicate that the natural fractures in the Longmaxi Formation in the study area are characterized by the coexistence of tectonic vertical and low-angle fractures. The core fractures exhibit high development density, short extension, and high filling degree. Comparison of imaging log fracture dip angles, core fracture cross-cutting relationships, fracture filling fluid inclusion tests, and rock acoustic emission experiments suggested that the fractures in the Longmaxi Formation in the Tiangongtang area were associated with three tectonic events. Combined with burial-thermal evolution history analysis, the formation periods were confirmed as follows: the first stage involved NW-oriented and NNE-oriented planar shear fractures, and NEE-oriented cross-sectional shear fractures formed during the mid-late Yanshanian period (130-62 Ma) with tectonic stress orientation near SN (345°±5°) and inclusion homogenization temperatures of 185-206 ℃; the second stage involved NE-oriented and NW-oriented planar shear fractures, and NNW-trending cross-sectional shear fractures formed during the late Yanshanian to mid-Himalayan period (62-34 Ma) with tectonic stress orientation near EW (80°±5°) and inclusion homogenization temperatures of 165-184 ℃; the third stage involved near SN-oriented and NEE-oriented planar shear fractures, and NE-oriented cross-sectional shear fractures formed from the mid-Himalayan period to present (34 Ma to present) with tectonic stress orientation near NW (315°±5°) and inclusion homogenization temperatures of 125-162 ℃. Based on the geomechanical background, a three-stage tectonic fracture evolution model for the Longmaxi Formation in the Tiangongtang area was established.

Gyrocheilos is a small genus of Gesneriaceae endemic to hight altitude mountains in Southwest China and Guangdong Province, with only five species. This genus is characterized by laterally bending style, which curves 90° at the top of the style and the stigma right at the mouth of floral tube. This unusual floral trait may have special evolutionary and adaptive mechanisms. In this paper, three Gyrocheilos species, i.e. G. chorisepalus, G. retrotrichus, G. microtrichus were examined to figure out the developmental patterns of floral lateral bending. Breeding systems, floral syndrome and pollination processes were also studied in G. retrotrichus at Dawuling Mountain, Guangdong Province, to explore its pollination adaptations. The results were as follows: (1) G. microtrichus had only left-bending style, while right-bending style were observed in several flowers (2%-3% of the total flowers) of G. chorisepalus and G. retrotrichus, although the individuals and populations were dominated by left-bending style. (2) Pollination observation found that style lateral bending occurred at the early stage of floral bud in G. retrotrichus, with two fertile stamens were anther-united and hidden at the middle of the floral throat, and there was no left and right mirror symmetry relationship with the lateral style. (3) The pollen-ovule ratio（P/O）was (456.98±15.55), belonging to facultative outcross breeding system. G. retrotrichus had a certain pollen limitation and self-pollination, but the germination rate of outcross seeds was higher, and there might be inbreeding decline. (4) There were few floral visitors and the frequency was low of G. retrotrichus. The main floral visitors were Halictidae, Bombus and Syrphidae. Bombus were large, and they landed on the bent style and the lower lip of the petals when visiting flowers. The side and lower part of the chest could effectively contact the stigma. (5) The detected reflected lights of flowers were composed of purple and blue-purple lights and the lower lips and outer floral tube with the highest reflection intensity, more likely to attract bees to land on the corolla's lower lip. Molecular phylogeny indicated that the closest genus of Gyrocheilos was Didymorcarpus, which was characterized by style downward bending and mirror-image flowers, suggesting the style lateral bending in Gyrocheilos probably evolved from either of these conditions. In conclusion, the lateral bending style might provide landing platform for pollinators and the stigma above the lower lips increase contact probability the floral visitors, which is an adaptation to the very low insect visitation due to fragmented and foggy habitats in high altitude areas.