[Monitoring and driving force analysis of net primary productivity in native grassland: A case study in Xilingol steppe, China]. / 天然草原净初级生产力变化监测与驱动力分析­­ä»¥é”¡æž—郭勒草原为例.

Grassland is an important type of terrestrial ecosystem. Using remote sensing technology to study the change and driving force of native grassland productivity at large scale is an important way to understand the ecological status of grassland. In this study, potential and actual net primary productivity (NPP) of Xilingol steppe from 2000 to 2018 were examined based on climatic model and light-use efficiency model, respectively. NPP damage value driven by human activities was calculated from the difference between potential and actual NPP. The least square method was used to analyze the temporal and spatial variation of NPP in Xilingol and the driving role of climate and human activities on NPP. The results showed that NPP in Xilingol increased from west to east, with mean annual NPP being 271.54 g C·m-2·a-1, the area with increased NPP (grassland restoration) being 36500 km2, and the area with decreased NPP (grassland degradation) being 59900 km2. The potential NPP tended to rise under the driving force of temperature and precipitation, with an average annual increase of 6.5 g C·m-2·a-1, which indicated that regional climate played a positive role in the improvement of NPP in Xilingol steppe, and that human activities were the main driving force for grassland degradation. The value of NPP damage driven by human activities decreased from east to west and from south to north, with the highest value in Wuzhumuqin meadow and southern steppe. Human activities, such as mining and reclamation, had the most obvious negative impact on grassland NPP.

The mechanism of kaempferol induced apoptosis and inhibited proliferation in human cervical cancer SiHa cell: From macro to nano.

Kaempferol has been identified as a potential cancer therapeutic agent by an increasing amount of evidences. However, the changes in the topography of cell membrane induced by kaempferol at subcellular- or nanometer-level were still unclear. In this work, the topographical changes of cytomembrane in human cervical cancer cell (SiHa) induced by kaempferol, as well as the role of kaempferol in apoptosis induction and its possible mechanisms, were investigated. At the macro level, MTT assays showed that kaempferol inhibited the proliferation of SiHa cells in a time- and dose-dependent manner. Flow cytometry analysis demonstrated that kaempferol could induce SiHa cell apoptosis, mitochondrial membrane potential disruption, and intracellular free calcium elevation. At the micro level, fluorescence imaging by laser scanning confocal microscopy (LSCM) indicated that kaempferol could also destroy the networks of microtubules. Using high resolution atomic force microscopy (AFM), we determined the precise changes of cellular membrane induced by kaempferol at subcellular or nanometer level. The spindle-shaped SiHa cells shrank after kaempferol treatment, with significantly increased cell surface roughness. These data showed structural characterizations of cellular topography in kaempferol-induced SiHa cell apoptosis and might provide novel integrated information from macro to nano level to assess the impact of kaempferol on cancer cells, which might be important for the understanding of the anti-cancer mechanisms of drugs. SCANNING 38:644-653, 2016. © 2016 Wiley Periodicals, Inc.

[Identification of mutation in PAX9 gene in a Mongolian family with non-syndromic oligodontia].

OBJECTIVE: To investigate the mutation in transcription factor paired box gene PAX9 in a mongolian family with non-syndromic oligodontia. METHODS: Peripheral blood was collected from 17 core family members (9 unaffected, 8 affected) in this Mongolian family with non-syndromic oligodontia. Mutation in exons of PAX9 gene was identified by PCR amplification and DNA sequencing. RESULTS: A point mutation c.87G > C at position 87 in exon 4 of PAX9 was identified from 8 affected members in the family, which were G/C heterozygous.While the 9 healthy members in the family were homozygous for C which was consistent with normal reference sequence in the GenBank(accession number: NC_000014). CONCLUSIONS: The mutation of c.87G > C (p. Ala240Pro) in exon 4 of PAX9 was likely to cause the non-syndromic oligodontia in this Mongolian family.

Anti-tumor activity evaluation of novel chrysin-organogermanium(IV) complex in MCF-7 cells.

Chrysin (5,7-dihydroxylflavone, Chry) is a natural product extracted from plants, honey, and propolis. In this work, a novel chrysin-organogermanium(IV) complex (Chry-Ge) with enhanced anticancer activities was synthesized, and its potential anticancer effects against cancer cells were measured using various methods. MTT results showed that Chry-Ge had significant inhibition effects on the proliferation of MCF-7, HepG2 and Colo205 human cancer cell lines in a dose-dependent manner while had little cytotoxic effects on MCF-10A human normal cells (MCF-10A cells) with the same treatment of Chry-Ge. These results suggested that Chry-Ge possessed enhanced anticancer effects and high selectivity between cancer cells and normal cells. The immuno-staining results showed that the nuclei of MCF-7 cells represented a total fragmented morphology and a disorganized cytoskeletal network in MCF-7 cells after Chry-Ge treatment. Besides, atomic force microscopy (AFM) was applied to detect the changes of ultrastructural and biomechanical properties of MCF-7 cellular membrane induced by Chry-Ge. The AFM data indicated that Chry-Ge treatment directly caused the decrease of cell rigidity and adhesion force of MCF-7 cells, suggesting that membrane toxicity might be one of the targets for Chry-Ge in MCF-7 cells. Moreover, the fluorescence-based flow cytometric analysis demonstrated that Chry-Ge could induce apoptosis in MCF-7 cells in ROS-dependent mitochondrial pathway. All results collectively showed that Chry-Ge could be as a promising anticancer drug for cancer therapy.