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This study aimed to investigate the interaction of A-kinase-interacting protein 1 (AKIP1) with C-X-C motif chemokine ligand (CXCL)1, CXCL2, CXCL8, and their effects on regulating glioblastoma multiforme (GBM) malignant behaviors. AKIP1 expression was modified by pcDNA and pGPH1 vectors in U-87 MG and U-251 MG cells. Subsequently, multiple compensative experiments were conducted via adding CXCL1, CXCL2 and CXCL8 in the pGPH1-AKIP1 (AKIP1 knockdown) transfected U-87 MG and U-251 MG cells, respectively. Furthermore, AKIP1, CXCL1/2/8 expressions in 10 GBM and 10 low-grade glioma (LGG) tumor samples were detected. AKIP1 was elevated in various GBM cell lines compared to normal human astrocytes. AKIP1 overexpression promoted U-87 MG and U-251 MG cell proliferation and invasion while inhibited apoptosis; and it enhanced chemoresistance to temozolomide (but not cisplatin) and radiation resistance; then AKIP1 knockdown showed the opposite effects. Meanwhile, AKIP1 positively regulated CXCL1/2/8, NF-κB pathway, AKT pathway and PD-L1 expression. Further multiple compensative experiments uncovered that CXCL1 and CXCL8 promoted proliferation, invasion, chemoradiation resistance, NF-κB pathway, AKT pathway and PD-L1 expression in U-87 MG and U-251 MG cells, also in pGPH1-AKIP1 (AKIP1 knockdown) transfected U-87 MG and U-251 MG cells; although CXCL2 exhibited similar treads, but its effect was much weaker. Besides, NF-κB pathway inhibitor and AKT pathway inhibitor attenuated the effect of CXCL1&CXCL8 on promoting GBM cell malignant behaviors. Clinically AKIP1 and CXCL1/8 were elevated in GBM compared to LGG tumor samples, and they were inter-correlated. AKIP1 promotes GBM viability, mobility and chemoradiation resistance via regulating CXCL1 and CXCL8 mediated NF-κB and AKT pathways.

Additional file 4 : Supplementary Table S4. The Egger’s test of different subgroup.

Additional file 6 : Supplementary Figure 1. Sensitivity analysis of the effect of the individual subgroup on the pooled ORs.

Additional file 5 : Supplementary Table S5. The Egger’s test of different subgroup.

The baker’s yeast Saccharomyces cerevisiae has become a powerful model in ecology and evolutionary biology. A global effort on field survey and population genetics and genomics of S. cerevisiae in past decades has shown that the yeast distributes ubiquitously in nature with clearly structured populations. The global genetic diversity of S. cerevisiae is mainly contributed by strains from Far East Asia, and the ancient basal lineages of the species have been found only in China, supporting an ‘out-of-China’ origin hypothesis. The wild and domesticated populations are clearly separated in phylogeny and exhibit hallmark differences in sexuality, heterozygosity, gene copy number variation (CNV), horizontal gene transfer (HGT) and introgression events, and maltose utilization ability. The domesticated strains from different niches generally form distinct lineages and harbor lineage-specific CNVs, HGTs and introgressions, which contribute to their adaptations to specific fermentation environments. However, whether the domesticated lineages originated from a single, or multiple domestication events is still hotly debated and the mechanism causing the diversification of the wild lineages remains to be illuminated. Further worldwide investigations on both wild and domesticated S. cerevisiae, especially in Africa and West Asia, will be helpful for a better understanding of the natural and domestication histories and evolution of S. cerevisiae.

The plateau of northwestern Yunnan is the most typical distribution region of plateau swamp developed on Karst landform in China.The Lake Bita coastal swamp listed as Wetlands of International Importance under the Ramsar Agreement is a typical representative in the region.Vegetation succession and its driving forces of coastal swamp are the key scientific issues related to theoretical research on swamp in the distinctive region.In the present study,two transects across coastal swamp were set up and sampled in narrow valley and broad valley in the coastal zone of Lake Bita respectively.The environment characteristics and species composition of swamp vegetation were surveyed.Pearson correlation test and Detrended Correspondence Analysis(DCA) were applied to analyze the relationship between species composition and surface water level,the distribution and succession and associated driving forces of swamp vegetation.Some important findings were revealed.Twenty-one families,35 genera,and 43 plant species were recorded along the two sampling transects.The highest number of species in family was observed in Cyperaceae and Ranunculaceae,each family contained six species and occupied 3.95% in total species of the vegetation community respectively,followed by Gentianaceae,which contained five species and hold sum total 11.63%.The highest number of species in genera were observed in Carex,Gentiana and Potamogeon,each genera contained three species,the second was Polygonum,it contained two species.At the transect scale,16 families,25 genera,and 28 species were recorded in the narrow valley transect,and 20 families,31 genera,and 37 species were recorded in the broad valley transect.L-shaped and U-shaped patterns of frequency distribution based on plant species were presented in the narrow valley transect and broad valley transect respectively.The swamp community also comprised some rare species(only occurred in one or two quadrats) in the two transects.Among them,11 and 10 rare species were observed in the narrow valley transect and broad valley transect separately,which accounted for 39.29% and 27.07%,respectively.The number of species occurred in two,three,five and fourteen quadrats in the broad valley transect was higher than that in the narrow valley transect.Species richness per quadrate and the total number of species showed similar patterns along the two transects and both showed significant correlation with surface water level,but Whittaker′s index did not.Along the two sampling transects the distribution of plant community mainly presented in the following ecological series of emerged hydrophytic communit→ swamp community→ swampy meadow community under the impact of surface water level and supplemented with community complexity under the impact of local microtopography.The distribution patterns of plant community in two transects depended on the lakeshore types and valley topography.In the narrow valley with steep shore,the plant community presented discontinuous distribution,whereas in the broad valley with gradual shore,the plant community showed continuous distribution.The distribution patterns and species composition represented by Lake Bita swamp community were dominated by multiple environmental factors characterized by surface water level and microtopography in the plateau region of Northwestern Yunnan.Correspondingly,there existed continuous succession mode and saltatory succession mode in the process of plant community succession,but the two modes were identical in succession direction.

Napahai wetland is a unique and seasonal marsh wetland located in the middle of Hengduan Mountains,northwestern Yunnan Plateau.In the recent decades,it has been seriously degraded under human disturbances,mainly including drainage and overgrazing.In the present paper,two kinds of typical degradation transects were established to evaluate the synergistic impacts of overgrazing stress and water regime and the single impacts of overgrazing stress in the lakeside of Napahai.The two transects were further classified into four degradation gradients,including primary wetland(PW),lightly degraded wetland(LW),moderately degraded wetland(MW) and severely degraded wetland(SW).Cluster analysis and principal component analysis(PCA) were conducted to explore the process and mechanism of wetland degradation as well as to evaluate the degree of wetland degradation quantitatively at system level of "vegetation-water-soil".The results were as follows: the numbers of plant families,genera and species as well as species diversity and richness all increased gradually from PW to SW,whereas species evenness remained stable.The plant community succession is in the direction of aquatic plant community →swamp plant community →swamp meadow plant community →meadow plant community.Correspondingly,the community changed towards more complicated structure characterized by the decreasing of helophyte and increasing of hygrophyte and mesophyte.Overgrazing stress changed the inherent mode of plant community succession and accelerated the degraded stage of "swamp meadow community" to some extent,although the direction of succession had not changed.The degradation characteristics of water properties varied in different disturbance type,the water indices of salinity,total alkalinity,total hardness,total nitrogen,ammonia nitrogen,nitrate nitrogen and total phosphorus all increased along the GD gradients,whereas decreased along the GAD gradients,depending on the water regime.Therefore,hydrologic alteration had a significant effect on wetland water properties.The changes of wetland soil properties were similar in the two disturbances.Among them,the contents of organic matter,total nitrogen and available nitrogen decreased,total phosphorous and total potassium(K) increased,whereas the available phosphorous and available potassium(K) showed no obvious changes.The vertical distribution for each nutrient content in the soil profiles of degraded wetlands varied greatly.Soil total phosphorous,available phosphorous and available potassium(K) decreased along the soil depth gradients.It showed that soil nitrogen content was the most obvious characteristics of wetlands degradation.In order to identify the driven factors of wetlands degradation under the multi-factorial stresses,PCA was employed to synthesize the degradation information from multiple aspects as discussed in this paper.Thirty indices based on vegetation,water and soil were simplified into three principal components by PCA,explained 54.8%,29.1% and 15.9% of the total variance,respectively.PCA results indicated that plant community was the most representative of wetlands degradation,and the soil structures and nutrient contents changed significantly along the degradation gradients of lakeside wetlands,Napahai.By contrast,the contributions made by water nutritional contents were lowest compared with vegetation and soil for wetlands degradation.Based on the three principle components derived from PCA,a multiple linear regression model,PC = 0.548 × PC1 + 0.291 × PC2 + 0.159 × PC3,was conducted to calculate the scores for each degradation stage,which could be taken to evaluate the wetlands degradation.

During the 21st century,economic development,urbanization and global climate change have caused the degradation of wetlands.This global problem has become a major research focus of present wetland science.Wetland degradation was also the main topic of the international wetlands conference held nearly 10 years.Research on wetland degradation has rapidly developed to form a large body of work;however,a unified theoretical framework has yet to emerge.There are still many questions that should be investigated,even if there is no uniform concept of wetland degradation.In China,study of wetland degradation has developed relatively slowly,and there has been a lack of quantitative,in-depth research.In this paper,we discuss the concept of wetland degradation and review the recent advances that have been made in wetlands degradation research in nine areas: wetland degradation standards,degradation characteristics,classification of degradation,degradation process and mechanism,index system for degradation monitoring,index system for degradation assessment,new technology for degradation monitoring,ecological restoration theory and technology of degraded wetlands.We also analyze current problems of wetland degradation in China and propose areas for future research.The findings from research show that the process and mechanism of wetland degradation arise from synergistic impacts of multiple stress factors.This includes climate change impacts on biogeochemical wetland processes,especially the nutrient cycling process,and on hydrological wetland processes at the catchment scale,particularly from rising sea levels.Theory and practice of wetland management for restoration and reconstruction,wetland degradation assessment and monitoring technology,wetland degradation assessment indexes and identification of stress factor intensity thresholds during wetland degradation have all been active areas of current research.Limitations of the present research on wetland degradation research in China include lack of deep understanding of the wetland degradation process and mechanism,imbalance in research intensity among geographic regions,failure to use modern research methods,lack of communication among researchers,lack of advanced theory and practice of degraded wetlands restoration.Accordingly,we suggest wetland degradation research should have the following aims: 1) to strengthen long-term,systematic study of wetland degradation;2) to investigate the processes and mechanisms of wetland degradation,specifically using quantitative methods;3) to encourage sharing of information and academic resources;4) to strengthen basic research of degraded coasts,estuaries,lakes and plain wetlands and develop detailed theories and methods so as to play their exemplary role to the outlying geographic regions;5) to apply the latest technologies;6) to enhance communication with other disciplines;7) to investigate the mechanisms of changes in biogeochemical processes of degraded wetland arising from the impacts of climate change and human disturbance;8) to strengthen research on the sustainable use of wetland ecosystems;9) to strengthen research on hydrological processes of degraded wetlands at the watershed scale;10) to strengthen research on wetland degradation assessment;11) to research important technologies for wetland restoration.We aim to promote wetland conservation,and stimulate research on wetland degradation and restoration as well as scientific management of degraded wetlands in China.