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Woody plants have showed great potential in remediating severely contaminated soils by heavy metals (HMs) due to their cost-efficient and ecologically friendly trait. It is believed the root-associated microbiota plays a vital role in phytoremediation for HMs. However, the ecological process controlling the assembly and composition of tree root-associated microbial communities under HMs stress remains poorly understood. Herein, we profiled the bulk soil, rhizosphere and endosphere microbial communities of trees growing in heavily Cd and Zn polluted soil. The microbiota was gradually filtered from bulk soil to the tree roots and was selectively enriched in roots with specific taxa, such as Proteobacteria and Ascomycota. The microbial community assembly along the soil-root continuum was mainly controlled by deterministic processes from bulk soil to the endosphere, with the normalized stochasticity ratio (NST) indices of 67.16-31.05 % and 30.37-15.02 % for bacteria and fungi, respectively. Plant selection pressure sequentially increased from bulk soil to rhizosphere to endosphere, with the reduced bacterial alpha diversity accompanying the consequently reduced complexity of the co-occurrence network. Together, the findings provide new evidence for horizontal transmission of endophytic microbiome from soil to the host, which can shed light on the future screening and application of microbial-assisted phytoremediation.

It is important to understand the variations in intraspecific growth performance for forest management. We evaluated the relationships among fine root traits, rhizobacterial community structure, and growth variables in different oak (Quercus acutissima) provenances. Four oak provenances with different growth performances were studied. In each provenance, growth variables, fine root traits, rhizosphere soil chemical properties, and rhizobacterial abundance were measured. The structure of rhizobacterial communities was assessed by 16S rRNA gene sequencing. The co-occurrence patterns of bacterial taxa were analyzed by network analysis. The relative contribution of fine root traits and rhizobacterial communities to variations in growth performance was evaluated by hierarchical partitioning analysis. Growth performance of the four oak provenances was positively correlated with the specific root length. The β-diversity of rhizobacterial communities, but not α-diversity, was positively correlated with the growth variables. The relative abundance of Actinobacteria (e.g., Actinospica and Conexibacter genera) increased with aboveground biomass. The co-occurrence network analysis showed more clusters with highly interconnected taxa in the high-yielding provenances. Variation in growth performance of oak in different provenances was significantly affected by the rhizobacterial community structure and fine root traits, with the former being a more prominent factor.

Provenance and stand management regimes greatly affect individual tree growth and stand productivity. The effects of provenance and initial planting density on growth and wood properties of 11-year-old sawtooth oak (Quercus acutissima Carruth.) plantations in eastern China were investigated. The average tree height growth, calorific values, and ash content of stem wood were greatly affected by provenance but not by initial planting density. The average tree diameter varied significantly among the three planting densities (5000, 2500, and 1667 trees ha−1) from tree age 6–11 years, and density-associated competition between trees mainly occurred at tree ages 6, 7, and 11 years for different provenances. The initial planting density and provenance had significant effects on the stand basal area (BA) and aboveground biomass (AGB). The annual growth in BA and AGB decreased in the eighth year after planting, especially in plots with an initial planting density of 5000 trees ha−1. The variances explained by the provenance exceeded the variance explained by the planting density for AGB at age 11 years. No significant interaction effect between initial planting density and provenance was observed for growth traits, but there was a significant effect on survival rate. Therefore, the suitable combination between provenance and planting density is crucial to increase productivity of sawtooth oak plantations. Additionally, our study confirms that, when the stands were young, initial planting density had a greater effect on productivity than provenance did, but this pattern reversed as stands aged.

Four bisnaphthalimides derivatives 3a, 3b, 5a and 5b with polyamine linkage have been synthesized and characterized. Different spectroscopic techniques, including UV–Vis spectroscopy, fluorescence spectroscopy, circular dichroism and fluorescence resonance energy transfer (FRET), have been used to explore the interaction of these compounds with G-quadruplex structures (Htelo, c-myc, c-kit). The compounds 3a, 3b and 5b show high affinity toward Htelo, c-myc and c-kit G-quadruplexes (Ka > 4.42 × 106 M−1), and exhibit more than 40-fold selectivity for the quadruplex versus CT DNA. Binding of 3a, 3b to telomeric and oncogenic G-quadruplexes induce strong enhancement of the fluorescence intensity (18–27-fold), whereas the duplex CT DNA induces much weaker fluorescence enhancement (around 2-fold). Being fluorescent, the cellular localization of 3a, 3b can be conveniently tracked by fluorescence imaging. The results indicate that 3a, 3b can readily be taken up by A549 lung cancer cells. Molecular docking studies indicate that 3a, 3b, 5a and 5b mainly bind in the groove and/or loop region of the G-quadruplexes, and hydrogen bonding plays an important role in the interaction of bisnaphthalimide derivatives with G-quadruplexes. CD spectroscopy and FRET melting assay indicate that 3a, 3b and 5b can promote the formation and the stabilization of human telomeric and c-myc G-quadruplex DNA. The compound 3b can inhibit the growth of A549 cells (IC50 = 0.15 μM), with a much higher antitumor activity than amonafide.

A model wetland with Salix was established to investigate the effects of CuO nanoparticles (NPs; the equivalent amount of Cu at 0, 100 and 500 mg/kg) on plant, soil enzyme activity and microbial community. Ionic Cu (100, 500 mg/kg) and bulk-sized CuO particles (BPs, 500 mg/kg) were included as controls. The results suggested the CuO NPs at 500 mg/kg and ionic Cu treatments inhibited the plant growth, while CuO NPs at 100 mg/kg and CuO BPs at 500 mg/kg played a facilitating role. CuO NPs significantly decreased the activities of peroxidase and polyphenol oxidase, while ionic Cu treatments increased peroxidase activity, BPs and ionic Cu (500 mg/kg) increased the polyphenol oxidase activity. Bacterial community richness and diversity were reduced in all Cu treatments; however, CuO NPs and BPs at 500 mg/kg significantly increased the richness and diversity of fungal community.Soil microbial community was significantly altered by Cu types and dose. In comparison with ionic Cu and CuO BPs, CuO NPs uniquely enriched the microbial community and the fungal families.Overall, it demonstrate that both particle size and dose regulate the impact of CuO on wetland ecology, which deepens our understanding on the ecological risks of CuO NPs in freshwater forested wetland.

A novel fluorescence probe PISOH comprising phenanthroimidazole as a fluorophore and thioacetal as recognition unit is designed and synthesized. PISOH displays high selective turn-on fluorescence response toward Hg2+ with no interference from other metal cations, such as Cu2+, Ag+, Fe3+, Pb2+, etc. PISOH can be converted to the corresponding aldehyde PICHO in the presence of Hg2+, based on the Hg2+ promoted deprotection of thioacetal. Moreover, the fluorescence emission and sensing properties of PISOH can be modulated by surfactants in aqueous solution. PISOH exhibits a detection limit (LOD) of 1.16 nM for Hg2+ in aqueous Triton X-100 solution, much lower than that in DMF (LOD = 6.83 nM). The response time of PISOH for Hg2+ is around 1 min, suitable for rapid detection of Hg2+. Furthermore, the probe can be used to monitor Hg2+ effectively in living cells by fluorescence imaging. This work represents a novel and simple strategy for sensing of Hg2+ in pure water by using commercially available surfactants to solubilize fluorescent probe.

Early brain injury (EBI) is a major cause of mortality from subarachnoid hemorrhage (SAH). We aimed to study the pathophysiology of EBI and explore the role of hepcidin, a protein involved in iron homeostatic regulation, and its downstream proteins. One hundred and thirty-two male Sprague–Dawley rats were assigned into groups (n = 24/group): sham, SAH, SAH + hepcidin, SAH + hepcidin-targeting small interfering ribonucleic acid (siRNA), and SAH + scramble siRNA. Three hepcidin-targeting siRNAs and one scramble siRNA for hepcidin were injected 24 h before hemorrhage induction, and hepcidin protein was injected 30 min before induction. The rats were neurologically evaluated at 24 h and euthanized at 72 h. Hepcidin, ferroportin-1, and ceruloplasmin protein expression were measured by immunohistochemistry and Western blotting. Brain water content, blood–brain barrier (BBB) leakage, non-heme tissue iron and Garcia scale were evaluated. Hepcidin expression increased in the cerebral cortex and hippocampus after experimental SAH (P

Mudflat reclamation has changed the ecological environment and soil properties in coastal areas. However, the variations in soil biological properties in areas with a history of coastal reclamation are still poorly understood. We studied the variations in chemical properties, soil microbial biomass carbon (SMBC), nitrogen (SMBN), and phosphorus (SMBP), soil microbial enzyme activity, and soil bacterial diversity in one tideland (native land) and four reclamation stages (reclaimed for 7, 22, 42, and 62 years). With the increase in reclamation time, soil salinity and pH decreased significantly, and the concentrations of soil organic carbon (SOC), total nitrogen, and total phosphorus increased. The concentrations of SMBC, SMBN, and SMBP and the activities of soil β-glucosidase, invertase, urease, and alkaline phosphatase continuously increased with the increase in reclamation time. The diversity and composition of soil bacteria exhibited less variation in natural grasslands (reclaimed for 7 years) compared with tidelands, and the diversity of soil bacteria was significantly higher in poplar plantations (reclaimed for 22, 42, and 62 years) compared with tidelands. The composition of soil bacteria in poplar plantations significantly differed among 22, 42 and 62-year reclaimed land, but no significant difference was observed between 42 and 62-year reclaimed lands. Compared with tideland, in the poplar plantations, the relative abundance of Proteobacteria and Actinobacteria decreased significantly, and the relative abundance of Acidobacteria increased by 391% - 468%. Bacterial communities showed nonrandom co-occurrence and modular patterns in the reclaimed land. Geodermatophilaceae, Bradyrhizobiaceae, Acidimicrobineae_incertae_sedis, and Reyranella were identified as the keystone taxa in the bacterial co-occurrence network. Multivariate regression tree analysis showed that variations in soil salinity and SOC were the key driving factors affecting soil bacterial diversity and community composition along the reclamation stages. Our study showed that the microbial properties of the topsoil layer in poplar plantations continuously improved in reclaimed coastal land.

Soil structure and microbial communities are sensitive to forest disturbance. However, little is known about the long-term effects of forest thinning on water-stable aggregates (WSA), and the community composition and diversity of soil microorganisms. In this study, we investigated soil chemical properties, WSA, and communities of bacteria and fungi in conventionally managed Chinese fir plantation stands and repeatedly thinned plantation stands with medium and high tree densities 18 years after the thinning treatments. The distribution patterns of WSA fractions were similar in the three thinning treatments. The mass proportion was the highest in the macro-aggregates fraction, followed by the clay + silt fraction, and it was the lowest in the micro-aggregates fraction. The soil organic carbon (SOC) concentrations in different WSA fractions decreased with decreasing aggregate size. The WSA fractions, stability, and aggregate-associated carbon were not significantly different among the three treatments 18 years after the thinning treatments. The total nitrogen concentration of the macro-aggregates fraction was significantly higher in the stands thinned intensively than in the conventionally managed stands. The abundance of minor bacteria and fungi species was different, although no significant differences were observed in the overall bacterial and fungal composition and diversity between the three treatments. Our results indicate that, compared with the conventionally managed stands, soil WSA stability and soil microbial communities in repeatedly thinned Chinese fir stands may recover over one rotation of Chinese fir plantation and that this is accompanied by the recovery of stand growth and soil nutrition.

Glioblastoma (GBM) is one of the most common highly malignant primary brain tumor with poor prognosis. This study aimed to explore the possible mechanism by bioinformatics method and detect potential function of UGP2 of GBM. Gene expression microarray data of GSE4412 and messenger RNA-sequencing data of GBM with samples clinical information were downloaded from the Gene Expression Omnibus database and The Cancer Genome Atlas database, respectively. Differentially expressed genes (DEGs) analysis using the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology based on R language. A total of 1000 common DEGs were identified in GBM samples, including 353 upregulated and 647 downregulated genes. Based on the random survival forest model, we identified UDP-glucose pyrophosphorylase 2 (UGP2) (upregulated gene) had a significant effect on GBM prognosis. Functional enrichment showed that UGP2 was enriched in the biological progresses of cell proliferation, migration, and invasion. Furthermore, UGP2 expression is aberrantly overexpressed in human glioma and positively correlated with pathologic grade. A loss-of-function study showed that knockdown of UGP2 decreases U251 cell growth, migration, and invasion in vivo and vitro. We proposed the development and progression of human glioma were associated with survival based on bioinformatics analysis. We also found that UGP2 might function as prognostic markers in the pathogenesis of GBM.

Malignant glioma is one of the most common primary brain tumors and is among the deadliest of human cancers. The molecular mechanism for human glioma is poorly understood. Early prognosis of this disease and early treatment are vital. Thus, it is crucial to target the key genes controlling pathogenesis in the early stage of glioma. In this study, differentially expressed genes in human glioma and paired peritumoral tissues were detected by transcriptome microarray analysis. Following gene microarray analysis, the gene expression profile in the differential grade glioma was further validated by bioinformatic analyses, co-expression network construction. Microarray analysis revealed that 1725 genes were differentially expressed and classified into different glioma stage. The analysis revealed 14 genes that were significantly associated with survival with a false discovery rate. Among these genes, macrophage capping protein (CAPG), a member of the actin-regulatory protein, was the key gene in a 20-gene network that modulates cell motility by interacting with the cytoskeleton. Furthermore, the prognostic impact of CAPG was validated by use of quantitative real-time polymerase chain reaction (qPCR) and immunohistochemistry on human glioma tissue. CAPG protein was significantly upregulated in clinical high-grade glioblastoma as compared with normal brain tissues. Overexpression of CAPG levels also predict shorter overall survival of glioma patients. These data demonstrated CAPG protein expression in human glioma was associated with tumorigenesis and may be a biomarker for identification of the pathological grade of glioma.

To observe the dynamic expression and significance of Toll-like receptor 3 (TLR3) in subarachnoid hemorrhage (SAH) model.SAH model was established using blood injection into the prechiasmatic cistern. Sixty SD rats were randomly divided into sham group and SAH groups (including SAH 1-, 3-, 7-day groups), each with 15 rats. The operation steps were the same in groups except the sham group that was injected with normal saline instead. At different time points after modeling, the basilar arteries and brain were obtained. The mRNA and protein expression of TLR3 was detected using reverse transcription PCR, Western blotting and immunohistochemistry, respectively. Meanwhile, the distribution of TLR3 was analyzed using the immunofluorescence double labeling technique.The mRNA and protein expression of TLR3 was weak in sham group and highly expressed in SAH groups, and the highest expression were found in SAH 3-day group. Immunohistochemistry showed that TLR3 was highly expressed in vascular endothelial and hippocampal neurons. The sham group showed a weak TLR3 expression in the cytoplasm, while the SHA group showed the strongly expressed TLR3 mainly in the nucleus and cytoplasm. The result of immunofluorescence double labeling also suggested TLR3 was co-localization with CD34 in the endothelial cells.The TLR3 expression was enhanced in the basilar arteries and hippocampus when the rats suffered from SAH, which suggested TLR3 might play a certain role in the pathogenesis of SAH.

Medical complications occur frequently after aneurismal subarachnoid hemorrhage (aSAH), such as cerebral vasospasm (CVS), anemia, etc. The relationship between hemoglobin (Hgb) concentration and the occurrence of CVS after aSAH remains largely elusive. A total of 218 patients with postoperative aSAH were recruited. Symptomatic cerebral vasospasm (SCVS) was initially diagnosed on the basis of their clinical signs and symptoms, and confirmed by imaging tests. The patients were then divided into four groups on the basis of the postoperative mean Hgb concentration (11, 11-12, 12-13, and13 g/dl). The possible influential factors that were statistically significant in the initial univariate analysis were subjected to a multivariable logistic regression analysis. Univariate analysis showed that Hunt and Hess neurological grade on admission, intraoperative aneurysm rupture, CT Fisher grade, and postoperative mean Hgb were associated significantly with SCVS in aSAH patients after surgical treatment (P0.05). Subsequent multivariable analysis showed that postoperative mean Hgb remained significant after adjustment for Hunt and Hess neurological grade on admission and CT fisher grade. The incidence of SCVS in the group with an Hgb concentration 11-12 g/dl was found to be the lowest among all groups [odds ratio (OR), 3.29, 95% confidence interval (CI), 1.43-7.58, P=0.005; OR, 3.63, 95% CI, 1.41-9.34, P=0.007; OR, 5.34, 95% CI, 1.85-15.43, P=0.002]. Postoperative Hgb concentration is an independent risk factor for SCVS in aSAH patients following surgery, and maintaining the concentration at 11-12 g/dl may reduce the incidence of SCVS.

Malignant glioma is one of the most common primary brain tumors that develop via multiple pathways and gene deregulation. MicroRNAs are involved in human cancer development and progression, and their serum expression profiles of glioma patients may be useful for classifying cancers. However, the profile and molecular mechanism of serum microRNAs for human glioma are poorly understood. Thus, it is crucial to analyze microRNA expression in human glioma serum to identify molecular subclasses and early stage of glioma. In this study, we performed microRNA alteration that contributes to glioma profile via analysis of The Cancer Genome Atlas RNA sequencing data and other independent Gene Expression Omnibus microarray data. We identified the glioma-associated novel microRNA as a key regulator of human glioma development and progression. The putative novel miR-1825 was validated by real-time polymerase chain reaction and its expression was significantly decreased in the serum of glioma patients compared with healthy controls. Patients with high miR-1825 expression had a longer survival rate. Interestingly, we found that miR-1825 expression levels were dependent on tumor size and pathological grading in glioma patients, but not associated with other factors including age and T classification. MicroRNA–Gene Ontology network indicated that miR-1825 may play an important role in the development of human glioma including apoptosis, cell proliferation, and invasion. In vitro assays of miR-1825 inhibit U87 cell proliferation and invasion and induce apoptosis. Furthermore, we provide evidence that the tumor-suppressive microRNA miR-1825 controls KLF2 expression. Reporter gene analyses revealed that both microRNAs directly targeted the 3′-untranslated region of KLF2 messenger RNA. These data demonstrated that miR-1825 expression in serum of human glioma was associated with tumorigenesis and miR-1825 may be used as a biomarker for identification of the pathological grade of glioma.