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River water quality has been increasingly deteriorated because of the influence of natural process and anthropogenic activities. Quantifying the influence of landscape metrics, namely topography and land use pattern, which encompass land use composition and landscape configuration, across different spatial and seasonal scales that reflect natural process and anthropogenic activities, is highly beneficial for water quality protection. In this study, we focused on investigating the effects of topography, landscape configuration and land use composition on water quality at different spatial scales, including 1-km buffer and sub-watershed, and seasonal scales, including wet and dry season, based on the monthly water quality data in 2016 of Dongting Lake in China. Multivariate statistical analysis of redundancy analysis and partial redundancy analysis was used to quantify the contributions of these factors under different scales. Our results showed that among the three environmental groups, topography made the greatest pure contribution to water quality, accounting for 11.4 to 30.9% of the variation. This was followed by landscape configuration, which accounted for 9.4 to 23.0%, and land use composition, which accounted for 5.9 to 15.7%. More specifically, water body made the greatest contribution to the water quality variation during dry season at both spatial scales, contributing 16.6 to 17.2% of the variation. In contrast, edge density was the primary interpreter of the variability in water quality during wet season at both spatial scales, accounting for 9.9 to 11.1% of the variation. The spatial variability in the influence of landscape metrics on water quality was not markedly distinct. However, these metrics have a minimal impact difference on water quality at the buffer scale and the sub-watershed scale. Moreover, the contribution of landscape configuration varied the most from the buffer to sub-watershed scales, indicating its importance for the spatial scale difference in water quality. The findings of this study offer useful insights into enhancing water quality through improved handling of landscape metrics. [ABSTRACT FROM AUTHOR]

Traditional pyrolysis biochar has been widely employed to treat dye wastewater. However, there are some problems in the pyrolysis process, such as the generation of harmful gases and the low content of silico-oxygen functional groups to promote adsorption. Straw biochar (Ac-BCbm) was prepared by sulfuric acid co-ball milling method. The adsorption performance and adsorption mechanism of rhodamine B (RhB) under different preparation conditions and factors were investigated. The results showed that the adsorption rate of Ac-BCbm on RhB was up to 94.9%, which was 60.5% and 55.8% higher than that of ball-milling straw (STbm) and biochar prepared by pyrolysis (STBC600), respectively. The Ac-BCbm had better adaptability under different pH and common interfering ions for remove RhB. Characterization and DFT simulation analysis revealed that the sulfuric acid co-ball milling process promoted the formation of Si–OH and Si–O-CH3 oxygen-containing functional groups of Si component in straw, which enhanced the hydrogen bonding interactions and effectively improved the adsorption efficiency. This study investigated a new strategy for biochar preparation by sulfuric acid co-ball milling, which provides an additional development direction for the efficient resource utilization of straw. [ABSTRACT FROM AUTHOR]

Purpose: Conducting research about the metal accumulation process of wetland plants and relevant rhizosphere mechanism can help better understand the biogeochemical behavior of metals in riparian wetland. However, little relative information is available for riparian wetland. Methods: In this study, we explored the copper accumulation process of dominant plant of Artemisia and rhizosphere mechanism under different water conditions (flooding condition [FC], dry condition [DC] and alternate dry and flooding condition [DFC]) in riparian wetland of Poyang Lake. Results: The results indicated that continuous or intermittent flooding may impede the accumulation and transformation of Cu by Artemisia. The correlation and multivariate analysis indicated that rhizosphere pH, Cu fraction and iron plaque on root surface can significantly influence Cu accumulation process. The transformation of exchangeable fraction to carbonate bound fraction and organic fraction under DFC and FC treatments of Cu may impede its accumulation in Artemisia. Formation of iron plaque under DFC and DC treatments can enhance the Cu accumulation in roots, but impede the translocation of Cu to aboveground tissues. Higher rhizosphere pH under DFC and FC treatments may impede the translocation of Cu by enhancing formation of iron plaque. Additionally, the translocation factor and root/aerial Cu content indicated that Artemisia has the potential for phytoextracting Cu, but the significant decrease of its biomass with Cu addition indicated that Artemisia is not suitable for phytoextracting Cu polluted soil, especially under DFC and FC treatment. Conclusion: DFC and FC treatments can significantly impede the Cu accumulation processes and ability by changing rhizosphere characteristics and decreasing plant growth. [ABSTRACT FROM AUTHOR]

Central nervous system injuries and diseases, such as ischemic stroke, spinal cord injury, neurodegenerative diseases, glioblastoma, multiple sclerosis, and the resulting neuroinflammation often lead to death or long-term disability. MicroRNAs are small, non-coding, single-stranded RNAs that regulate posttranscriptional gene expression in both physiological and pathological cellular processes, including central nervous system injuries and disorders. Studies on miR-124, one of the most abundant microRNAs in the central nervous system, have shown that its dysregulation is related to the occurrence and development of pathology within the central nervous system. Herein, we review the molecular regulatory functions, underlying mechanisms, and effective delivery methods of miR-124 in the central nervous system, where it is involved in pathological conditions. The review also provides novel insights into the therapeutic target potential of miR-124 in the treatment of human central nervous system injuries or diseases. [ABSTRACT FROM AUTHOR]

Irreversible neuron loss caused by central nervous system injuries usually leads to persistent neurological dysfunction. Reactive astrocytes, because of their high proliferative capacity, proximity to neuronal lineage, and significant involvement in glial scarring, are ideal starting cells for neuronal regeneration. Having previously identified several small molecules as important regulators of astrocyte-to-neuron reprogramming, we established herein that miR-124, ruxolitinib, SB203580, and forskolin could co-regulate rat cortical reactive astrocyte-to-neuron conversion. The induced cells had reduced astroglial properties, displayed typical neuronal morphologies, and expressed neuronal markers, reflecting 25.9% of cholinergic neurons and 22.3% of glutamatergic neurons. Gene analysis revealed that induced neuron gene expression patterns were more similar to that of primary neurons than of initial reactive astrocytes. On the molecular level, miR-124-driven neuronal differentiation of reactive astrocytes was via targeting of the SOX9-NFIA-HES1 axis to inhibit HES1 expression. In conclusion, we present a novel approach to inducing endogenous rat cortical reactive astrocytes into neurons through co-regulation involving miR-124 and three small molecules. Thus, our research has potential implications for inhibiting glial scar formation and promoting neuronal regeneration after central nervous system injury or disease. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNA), endogenous non-coding RNAs approximately 22 nucleotides long, regulate gene expression by mediating translational inhibition or mRNA degradation. Exosomes are a tool for intercellular transmission of information in which miRNA exchange plays an important role. Under pathophysiological conditions in the central nervous system (CNS), cellular transmission of exosomal miRNAs can regulate signaling pathways. Exosomal miRNAs are involved in the occurrence and development of diverse CNS diseases, such as traumatic brain injury, spinal cord injury, stroke, neurodegenerative diseases, epilepsy, and glioma. The use of exosomes as transport vehicles for certain miRNAs provides a novel therapeutic strategy for CNS diseases. Furthermore, the exosomes in body fluids change with the occurrence of diseases, indicating that subtle changes in physiological and pathological processes in vivo could be recognized by analyzing exosomes. Exosomal analysis is expected to act as a novel tool for diagnosis and prediction of neurological diseases. In this review, we present the current understanding of the implications of miRNAs in CNS diseases and summarize the role and mechanism of action of exosomal miRNA in nervous system disease models. [ABSTRACT FROM AUTHOR]

Atorvastatin therapy in chronic subdural hematoma patients has attracted more and more clinical attention. To evaluate the efficacy of atorvastatin in the treatment of chronic subdural hematoma. A systematic literature search was performed in the PubMed, Embase, and Cochrane Library databases; related controlled trials comparing the efficacy of atorvastatin in the treatment of chronic subdural hematoma published from inception to December 2018 were collected. We used Cochrane risk of bias method to evaluate the quality of the included studies. Meta-analysis was used to analyze the included data by RevMan 5.3 software. Of the 53 retrieved studies, 6 trials were included. Results of meta-analysis showed that compared with chronic subdural hematoma patients without atorvastatin treatment, both in patients who have had surgery and those who have not, atorvastatin were effective in reducing the incidence of recurrence requires surgery (OR = 0.30, 95% CI 0.19–0.48, P < 0.00001). And improve the recovery rate of neurological function of patients (OR = 1.75, 95% CI 1.08–2.83, P = 0.02). This meta-analysis suggests that patients with chronic subdural hematoma can improve their prognosis after receiving atorvastatin. Additionally, the neurological function recovery appears to be improving by atorvastatin. [ABSTRACT FROM AUTHOR]

Metal pollution has been a serious problem facing river systems worldwide, which can adversely affect human health through food chain. The goal of this study was to determine the distribution, sources, and health risk of dissolved metals (Cr, Mn, Ni, Cu, Zn, As, Cd, Pb, Al, Sb, V, Co, Mo) in major rivers located in the hilly area of southeastern China (namely, Jiulongjiang River (JL), Minjiang River (MJ), Oujiang River (OJ), Qiantangjiang River (QT), Raohe River (RR), Fuhe River (FR), Xinjiang River (XR), Ganjiang River (GR), Xiushui River (XS), Xiangjiang River (XJ), Zishui River (ZR), Yuanjiang River (YR), Lishui River (LR)) during dry and wet seasons. Results indicated that metal concentrations were spatially and temporally distinct. Metals of Mn, Ni, Cu, Cd, Sb were significantly higher in specific rivers than other metals. And metals of Cr, Ni, As, and Al concentrations were obviously higher in dry season than in wet season. The comparison with drinking water guidelines of China and other countries indicated that waterbodies were polluted higher by Al than other metals at most sites. Metals in JL and XJ may have health risk to local adults with hazard index (HI) > 1. While special attention should be paid to As, which had a potential carcinogenic risk to adults in study area with CR higher than the critical value. Source analysis with statistical method indicated that point and non-point pollutants from anthropogenic activities are the main sources of metals, with the exception of Al, Ni, V, Cr, and Mo that were mainly from natural processes. This study could be useful for the management and protection of the China's Southern hilly area river systems. [ABSTRACT FROM AUTHOR]

Purpose: River sediment, the important sink and source of heavy metals, can provide critical information for aquatic ecosystem health. Heavy metal pollution has been a serious problem facing river systems worldwide and can adversely affect human beings via the food chain. However, no comprehensive study has been conducted on heavy metal pollution in sediments of river systems in the hilly area of southern China, which plays a key role in water supply and ecosystem balance. This study is aimed at comprehensively studying the pollution status of heavy metals in river sediments in the hilly area of southern China and apportioning sources. Materials and methods: A total of 39 superficial sediment samples were collected from the upstream, midstream, and downstream of 13 rivers (Xiangjiang River, Zishui River, Yuanjiang River, and Lishui River located in Hunan Province; Ganjiang River, Xinjiang River, Fuhe River, Raohe River), and Xiushui River located in Jiangxi Province; Qiantangjiang River and Oujiang River located in Zhejiang Province; Minjiang River and Jiulongjiang River located in Fujian Province) in the hilly area of southern China. The total concentrations of metals of Mn, Zn, Cr, Co, Ni, Cu, As, Cd, Sb, Pb, and V were analyzed using the inductively coupled plasma-mass spectrometry method. The pollution status and potential ecological risk were assessed with the geoaccumulation index (Igeo), sediment quality guidelines (SQGs), and potential ecological risk index (RI). The source apportionment of heavy metals was performed by correlation analysis and principle component analysis (PCA). Results and discussion: Results indicated that Mn, Zn, and Pb concentrations were significantly higher than other metals, especially in the upstream of the Jiulong River and midstream and downstream of the Xiangjiang River. Pollution assessment indicated that Cd pollution of sediments was most serious and that more than 50% of sampling sites were significantly polluted, with a very high potential ecological risk. The rivers in Hunan provinces (HN) were identified as the priority controlled rivers because of the high Igeo and RI index values. Correlation and PCA analysis indicated that Mn, Pb, and Zn originated from natural and mineral exploitation activities; As, V, Ni, and Sb originated from industrial wastewater and mineral-smelting activities; Cu and Co originated from agricultural activities; Cr and Ni originated from natural sources. While the most polluted Cd came from a combination of multiple sources described above. Conclusions: Results indicated that Cd was the most common heavy metal pollutant, especially in river sediments of Hunan Province. Anthropogenic activities have become the main source of heavy metals in the river sediments of the hilly area of southern China. Special attention should be paid to Cd, and measures must be taken to prevent from further anthropogenic influence on heavy metal pollution. [ABSTRACT FROM AUTHOR]

The interactions between soil organic matter (SOM) and micro-topography and vegetation drive the ecology of wetland ecosystems. We investigated the distribution pattern of SOM and its relationships with elevation, slope, aspect, topographic wetness index (TWI), and normalized difference vegetation index (NDVI) in Poyang Lake, the largest freshwater lake of China. The local parameters were obtained by applying a geographically weighted regression model. Local parameter differences were analyzed between two dominant wetland types (dish-shaped pit wetland and delta wetland) and among nine land-cover types (deep water, shallow water, very shallow water, mudflat, meadow, sparse grassland, Carex-Phalaris community, Phragmites-Triarrhena community, and Artemisia-Cynodon community). The SOM response to elevation was most sensitive in the dish-shaped pit wetland and mudflat, whereas the effects of slope on SOM were more significant in the delta wetland and vegetated land-cover types. Relatively weaker correlations were observed between SOM and aspect in all study zones. Positive correlations were found between SOM and TWI, which was strongest in dish-shaped pit wetland and deep water. NDVI was positively related to SOM in most areas, but the relationships were not significant in the southern area and in the mudflat. This study helps to better understand the spatial heterogeneity of Poyang Lake. [ABSTRACT FROM AUTHOR]

As an important wetland with international significance in biodiversity conservation, Poyang Lake is under severe pressure from increasing human activities, such as prescribed fire. In this study, a fire-prone plant community (Triarrhena lutarioriparia L. Liou) was selected in Poyang lake, and a 5-year study on annual prescribed fire and corresponding monitoring were conducted in this representative plant community. Results showed that sprout density, plant height and biomass of burn samples were significantly higher than those of the control. However, burn samples presented significantly lower values of species richness and community biodiversity in the later period. Furthermore, periodical fire significantly promoted the availability of nitrogen and phosphorous in surface soil, which were closely and positively related to height, dominance and biomass of T. lutarioriparia.. Considering the positive influences on the plant traits and species composition, prescribed fire could potentially be used as an effective means to maintain the ecological health of Poyang Lake. [ABSTRACT FROM AUTHOR]