RESUMO
Investigating eco-hydrology in desert grasslands is pivotal to comprehend the dynamic evolution patterns of vegetation. Nonetheless, a research void persists in understanding the eco-hydrological mutual feedback mechanisms associated with hydrological connectivity and the corresponding health index evaluation of a small watershed. This study is centered on the Shangdong River watershed in Inner Mongolia and uses SWAT (Soil and Water Assessment Tool) to simulate hydrological processes. The hydrological connectivity index (IC) was employed as a link to conduct Pearson correlation analysis and Granger causality tests on ecological and meteorological-hydrological factors. Additionally, the PSR model was utilized to assess the ecological health status of the watershed. Key findings reveal the following: (1) The NDVI in the Shangdong River watershed showed an overall upward trend from 2007 to 2018, while IC exhibited an overall downward trend. Temporally and spatially, there was a significant negative correlation between IC and NDVI. (2) During the vegetation growth season, IC serves as a pivotal link in the feedback loop of eco-hydrological processes. Temperature drives vegetation growth, which in turn affects IC. IC regulates soil moisture content and evaporation, further influencing vegetation growth, thus forming a feedback mechanism. (3) Over the study period, the Grassland Health Composite Index (GHI) demonstrated a consistent rise, averaging 0.44, signaling a suboptimal state for the grassland ecosystem. Furthermore, a negative correlation was observed between GHI and IC. Consequently, regulating IC could play a crucial role in safeguarding and rejuvenating the grassland ecosystem. This study offers theoretical and data support for understanding eco-hydrological processes and effective pasture management of the desert grassland watershed.
RESUMO
Objective To investigate the effect of antisense oligonucleotides of miRNA-34a on non-small cell lung cancer (NSCLC) and its molecular mechanism.Methods The expression of miRNA34a in human non-small cell lung cancer cell line HCC827 and human normal lung cell MRC-5 was detected by real time fluorescence quantitative polymerase chain reaction (qRT-PCR).HCC827 cells were divided into three groups:blank control group,negative control group,anti-sense oligonucleotide group (liposome 2000 transfected anti-sense oligonucleotide miRNA-34a);cell counting kit-8 (CCK-8) method was used to detect cell proliferation,Jimsa staining was used to detect cell cloning ability,Transwell test was used to detect cell migration and invasion ability;RT-PCR and Western blot were used to detect phosphatase and tensin homolog (PTEN),phosphorylation-protein kinase B (p-Akt),phosphatidylinositol-3-kinase (PI3K)mRNA and protein expression.Results The relative expression of miRNA34a in HCC827 cells was significantly higher than that in human normal lung cells (P ＜ 0.01).The relative expression of miRNA34a in antisense oligonucleotide miRNA-34a group was significantly lower than that of negative control group and blank control group (P ＜ 0.05),and there was no significant difference between negative control group and blank control group (P ＞ 0.05).At 48 h,72 h and 96 h,the proliferation level of HCC827 cells in antisense oligonucleotide miRNA-34a group was significantly lower than that in negative control group and blank control group (P ＜ 0.05).The cell cloning rate of antisense oligonucleotide miRNA-34a group was significantly lower than that of negative control group and blank control group (P ＜ 0.01).The number of migration and invasion of HCC827 cells in antisense oligonucleotide RNA-34a group was significantly lower than that in negative control group and blank control group (P ＜0.01).The relative expression of PTEN mRNA and protein in antisense oligonucleotide miRNA-34a group was significantly higher than that in negative control group and blank control group (P ＜ 0.05);the relative expression of p-Akt,PI3K mRNA and protein in antisense oligonucleotide miRNA-34a group were significantly lower than that in negative control group and blank control group (P ＜ 0.05).Conclusions The expression level of miRNA-34a in human nonsmall cell lung cancer cells is significantly higher than that in human normal lung cells.Antisense oligonucleotides of miRNA-34a can inhibit the proliferation,cloning,migration and invasion of human non-small cell lung cancer cells.The mechanism may be related to the negative regulation of PTEN/p-Akt/PI3K signaling pathway.