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Objective: To investigate the role and clinical application of microRNA in the malignant progression of colorectal cancer (CRC). Methods: The transcriptome data of human colorectal cancer and adjacent tissues from TCGA database were analyzed to screen out the differentially expressed microRNAs (miRNAs), among which miR-1229-3p with the most significant difference was selected as the target miRNA, and furthermore the expression of miR-1229-3p was verified through GEO and Starbase databases. The biological functional characteristics of miR-1229-3p was analyzed through Bioinformatics. The miR-1229-3p overexpression cell line and miR-1229-3p knockdown cell line were constructed. The effect of miR-1229-3p on the proliferation, metastasis, and apoptosis of CRC cells was explored in vitro by CCK-8 experiment, cloning formation experiment, EdU experiment, transwell, and flow cytometry experiment. The effect of miR-1229-3p on the prolife-rative capacity of CRC in vivo was explored by nude mouse transplantation tumor experiment. The target genes of miR-1229-3p were screened out by DIANA, TargetScan, and miRDB databases. KEGG and GO were used to analyze the biological function of target genes. The expression of miR-1229-3p in plasma exosomes of 60 CRC patients and 60 healthy examiners obtained from Nanjing First Hospital were analyzed, and receiver operating characteristic curve (ROC) was used to distinguish its diagnostic efficacy for CRC patients. Results: The expression of miR-1229-3p was downregulated in CRC cells and tissues. Bioinformatics predicted a significant negative correlation between miR-1229-3p and tumor progression pathways, such as epithelial-mesenchymal transition and angiogenesis (R

As a plant kingdom and a biodiversity hotspot, Yunnan is a key region for our understanding of modern and past global changes in biodiversity and environment. As proxies of vegetation and climate, phytoliths have become increasingly important in ecological and paleoecological studies. In this study, phytolith analysis was carried out on samples of surface sediments from 70 lakes in western Yunnan, southwest China. These lakes are surrounded by modern vegetation types including broadleaved and coniferous forests, scrubs, grasslands, meadows, and alpine vegetation. The results of this study show that modern lacustrine phytoliths in western Yunnan are dominated by herbaceous phytoliths, among which Poaceae types are the most abundant. The 70 phytolith samples used can be divided into 4 groups, reflecting the major vegetation types from which samples were collected. The principal component analysis (PCA) and redundancy analysis (RDA) of the phytolith and climatic data of the 70 lacustrine phytolith samples showed that temperature and precipitation are the climatic parameters controlling the spatial distribution of phytolith assemblages in western Yunnan. Phytolith–MAT (mean annual temperature) and phytolith–MAP (mean annual precipitation) transfer functions were developed using weighted averaging partial least squares (WA-PLS), and both the MAT and MAP functions showed good performances (MAT: R2 = 0.67, RMSEP = 0.96 °C, MAP: R2 = 0.64, RMSEP = 140.4 mm). Our results also reveal that phytolith analysis is a useful technique offering reliable vegetation interpretation and climate reconstruction; thus, this study provides a basis for the vegetational and climatic interpretation of fossil lacustrine phytolith records in western Yunnan. [ABSTRACT FROM AUTHOR]

Vegetation dynamics data since the Last Glacial Maximum (LGM) are essential for our understanding of ecosystem shifts and vegetation responses to climate change. Here, we present a pollen record covering the last 25,000 years from Lake Fuxian in central Yunnan, southwest China. Our study shows seven stages of vegetation dynamics since the LGM: The early LGM (stage 7 of 25,000–21,200 cal. a BP) witnessed less dense regional vegetation dominated by pine forests, evergreen broadleaved forests (EBFs), deciduous broadleaved forests (DBFs), montane hemlock forests, and fir/spruce forests. The late LGM (stage 6 of 21,200–17,500 cal. a BP) saw an expansion of grasslands, wetlands, and montane fir/spruce forests as well as a shrinkage of EBFs and DBFs. During the last deglaciation (stage 5 of 17,500–13,300 cal. a BP), dense regional vegetation was dominated by EBFs as well as deciduous oak and alder forests. The densest regional vegetation occurred in stage 4 of 13,300–11,200 cal. a BP, roughly equal to the Younger Dryas Chron, when pine forests, DBFs, EBFs, grasslands, and wetlands grew in the Lake Fuxian catchment. During the early to mid-Holocene (stage 3 of 11,200–5000 cal. a BP), dense regional vegetation was dominated by sweetgum forests, in addition to some pine forests and EBFs. After 5000 cal. a BP, the regional vegetation density became lower and lower, and forests became thinner and thinner. Pine forests expanded to their maximum of the entire sequence in stage 2 of 5000–2500 cal. a BP. A big deforestation event occurred in stage 1 (the last 2500 years), when grasslands, wetlands, and cultivated vegetation dominated regional vegetation in the catchment of Lake Fuxian. The regional vegetation since the LGM in the catchment of Lake Fuxian also experienced six major transitions, five centennial shift events, and one big large-scale and long-term deforestation event. These resulted from the responses of regional vegetation to climate changes during the LGM, last deglaciation, and early–mid-Holocene, as well as human influence in the late Holocene. The vegetation density since the LGM has changed with the 25° N summer insolation. [ABSTRACT FROM AUTHOR]