Hydroxide ion is a common electrolyte when electrode reactions take place in alkaline media. In the case of oxygen reduction reaction on Pt(111), we demonstrate by ab initio molecular dynamics ...calculations that the desorption of hydroxyl (OH*) from the electrode surface to form a solvated OH– is a cross-sphere process, with the OH* reactant in the inner sphere and the OH– product directly generated in the aqueous outer sphere. Such a mechanism is distinct from the typical inner sphere and outer sphere reactions. It is dictated by the strong hydrogen bonding interactions between a hydroxide ion and water molecules and is facilitated by proton transfer through solvation layers. It should play a significant role whenever OH* desorption, or its reverse, OH– adsorption, is involved in an electrochemical reaction.
•Elevated concentrations of heavy metals were observed in the soil, crop, well water, and freshwater fish.•Health risk of heavy metal contamination was significant for local inhabitants.•Consumption ...of rice was the major contribution to risk.•Most of the risks were due to Cd and As contamination.
Heavy metal contamination due to mining activity is a global major concern because of its potential health risks to local inhabitants. In the present study, we investigated the levels of Cd, Cu, Pb and As in soil, crop, well water and fish samples collected from the vicinity of the Tonglushan mine in Hubei, China, and evaluated potential health risks among local residents. Results indicate that soils near the mine were heavily contaminated with Cd (2.59mgkg−1), Cu (386mgkg−1), Pb (120mgkg−1) and As (35.4mgkg−1), and exceeded the soil quality standard values of Cd and Cu contamination. The concentrations of Cd, Cu, Pb and As in crop samples grown in mine-affected soils were significantly higher than those of the reference soils. The concentrations of Cd and As in most vegetables grown in mine-affected soils exceeded the maximum allowable level (MAL). The Cd, Pb and As concentration in rice grain collected from mine-affected soils were 2.95, 1.85 and 2.07-fold higher than the MAL, respectively. The concentrations of Cd and As in fish muscle from the mine-affected area were above national MAL in 61% and 34% of analyzed samples, respectively. All measured heavy metals except Pb were significantly greater in well water in the mine-affected area than those in the reference areas. The average estimated daily intakes of Cd and As were beyond the provisional tolerable daily intake, respectively. The intake of rice was identified as a major contributor (⩾72%) to the estimated daily intake among the residents.
Neurotransmitters are biologically active molecules that are crucial for the regulation of normal physiological functions in the central and peripheral nervous systems. Therefore, accurate detection ...of neurotransmitters is significant in many applications, such as clinical diagnosis, biological analysis, and pathological research. However, quantitative analysis of neurotransmitters is difficult as they are released dynamically and at very low concentrations (e.g., dopamine is released at concentrations of 0.065–0.326 nM) 64. In this regard, microelectrodes have attracted considerable attention as electrochemical biosensors owing to their excellent sensitivity, high response rate, and high stability. Among the various electrode materials, carbon has shown high potential owing to its high electrical conductivity and low cost. Moreover, carbon-based microelectrodes can be used in real time in vivo to detect neurotransmitters. This review summarizes the various carbon-based microelectrodes developed as biosensors and discusses their sensitivity and limit of detection with regard to neurotransmitters. The review provides insight into the development of carbon-based microelectrodes as biosensors to detect neurotransmitters and the future prospects and commercialization capabilities of such devices.
•C-based microelectrodes as electrochemical biosensors can detect neurotransmitters.•Main monoamines, amino acids, and other neurotransmitters were reviewed in detail.•Neurotransmitter analysis and detection technologies were reviewed.•Development prospects of C-based microelectrodes for in vivo monitoring were proposed.
Fungi are key components of microbial communities in mangrove wetlands, with important roles in the transformation of nutrients and energy. However, existing studies typically focus on cultivable ...fungi and seldom on the structure and driving factors of entire fungal communities. The compositions, community assembly, and interaction patterns of mangrove fungal communities on a large scale remain elusive. Here, biogeography, assembly, and co-occurrence patterns of fungal communities in mangroves across eastern to southern China were systematically analyzed by targeting the entire internal transcribed spacer (ITS) region with high-throughput Pacific Biosciences single-molecule real-time sequencing. The analysis revealed a high level of fungal diversity, including a number of basal fungal lineages not previously reported in mangroves, such as
and
. Beta nearest-taxon index analyses suggested a determinant role of dispersal limitation on fungal community in overall and most individual mangroves, with support from the strong distance-decay patterns of community similarity. Further, nonmetric multidimensional scaling analyses revealed similar biogeographies of dominant and rare fungal communities. A minor role of environmental selection on the fungal community was noted, with geographical location and sediment depth as crucial factors driving the distribution of both, the dominant and rare taxa. Finally, network analysis revealed high modularized co-occurrence patterns of fungal community in mangrove sediments, and the keystone taxa might play important roles in microbial interactions and ecological functions. The investigation expands our understanding of biogeography, assembly patterns, driving factors, and co-occurrence relationships of mangrove fungi and will spur the further functional exploration and protection of fungal resources in mangroves.
As key components of microbial community in mangroves, fungi have important ecological functions. However, the fungal community in mangroves on a large scale is generally elusive, and mangroves are declining rapidly due to climate change and anthropogenic activities. This work provides an overview of fungal community structure and biogeography in mangrove wetlands along a >9,000-km coastline across eastern to southern China. Our study observed a high number of basal fungal lineages, such as
and
, in mangrove sediments. In addition, our results highlight a crucial role of dispersal limitation and a minor role of environmental selections on fungal communities in mangrove sediments. These novel findings add important knowledge about the structure, assembly processes, and driving factors of fungal communities in mangrove sediments.
•Antiviral drugs were frequently detected in 7 WWTPs in Guangdong.•Most of antiviral drugs cannot be efficiently removed in these WWTPs.•The estimated usage and emissions of antiviral drugs were 77.8 ...t/y and 13.2 t/y in Guangdong.•Zidovudine, ritonavir, lopinavir, and telbivudine could pose high ecological risks for aquatic environment.
Antiviral drugs are among the most common and important classes of pharmaceuticals to treat viral infections, however their continuous emission and persistence in the receiving environment has attracted increasing attention about their potential ecological risks. Here we investigated the occurrence, fate and mass load of 9 antiviral drugs for acquired immunodeficiency syndrome and hepatitis B, in 7 wastewater treatment plants (WWTPs) with different treatment processes in Guangdong, China. Totally, 8 target antiviral drugs were detected in the WWTPs influent wastewater, effluent wastewater and sludge, with maximal concentrations up to 7624 ng/L (telbivudine), 568 ng/L (telbivudine), and 2013 ng/g wet weight (telbivudine), respectively. The removal efficiency varied widely between different antiviral drugs, with the mean aqueous removal efficiency and total removal efficiency ranging from -6.2% (nevirapine) to 100% (lamivudine) and -1.2% (nevirapine) to 100% (lamivudine), respectively. Mass balance analysis showed that their elimination was mostly attributed to the biodegradation/biotransformation. The total back-estimated usage and emission of 9 target antiviral drugs were 77.8 t/y and 13.2 t/y in Guangdong province, China, respectively. Based on the sewage epidemiology approach, the consumption and emission of antiviral drugs in seven studied WWTPs were ranged at 2.31 mg/d/1000 people (nevirapine) to 4970 mg/d/1000 people (telbivudine), and 0 (lamivudine) to 900 mg/d/1000 people (telbivudine), respectively. Preliminary risk assessment showed that the antiviral drugs of zidovudine, ritonavir, lopinavir, and telbivudine in the receiving rivers could pose high ecological risks for aquatic environment. The findings from the present study illustrate the persistence of nevirapine in WWTPs, and provide essential evidence for further study into the development of wastewater treatment technologies.
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•The effects of multiple factors in green space on airborne microbes were detected.•Airborne bacterial and fungal pathogens differed in four functional zones.•Greenness and plant species shaped AM ...community and control airborne pathogens.•Masson pine with >30% significantly reduced the relative abundance of pathogens.
Urban green space has been implicated in shaping airborne microbes, but there is an only rudimentary understanding of the key factors of urban green space affecting the composition and structures of airborne microbes. Here, we selected 40 urban sites based on stratified random sampling design and investigated the effects of multiple factors including landscapes, plant, soil, and anthropogenic factors on airborne microbial communities, especially bacterial and fungal pathogens. Bacterial and fungal communities in the control area with lower greenness were significantly (P < 0.05) different from those in other areas with a gradient of green space. The relative abundance of bacterial and fungal pathogens significantly (P < 0.05) decreased with increasing greenness. Other than soil thickness, soil type, slope position, and population density, plant species considerably contributed to the shift in the composition and abundance of potential bacterial and fungal pathogens. A significantly (P < 0.05) reduced abundance of bacterial and fungal pathogens was observed in areas with >30% masson pine. Together, these results provide insights into the importance of green space for providing health benefits for city dwellers by reducing pathogens in air, as well as providing support for the inclusion of plant species in the management of urban green space to reduce exposure risk of airborne pathogens.
SIN supressed angiogenesis in RA via HIF-1α–VEGF–ANG-1 axis. To treat with SIN could depress the arthritis index, histopathologic scores and microvessel density, downregulated the level of HIF-1α, ...VEGF and ANG-1 in peripheral serum and CIA synovium. CFA, complete Freund’s adjuvant; CII, type II collagen; HIF-1α, hypoxia-inducible factor-1α; VEGF, vascular endothelial growth factor; ANG-1 angiopoietin 1.
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•Erythema and mild swelling were induced in collage-induced arthritis mice model and could ameliorated by SIN treated.•The changes of histopathological scores on inflammation, cartilage damage and bone erosion were observed.•Angiogenesis were observed at the chronic inflammatory state and could be inhibited by SIN treated.•The HIF-1α–VEGF–ANG-1 axis played important role in angiogenesis, and their expresses could suppress by SIN treated.
The objective of the present study is to investigate the inhibitory effects of sinomenine (SIN) on angiogenesis in a collagen-induced arthritis (CIA) mouse model.
Arthritis assessments for all mice were recorded. The histopathological assessments were performed following haematoxylin and eosin (HE) staining. Immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) analyses were used to detect the expression of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and angiopoietin 1 (ANG-1) in the serum and in the membrane. Immunohistochemistry was employed to detect the synovium microvessel density (MVD).
Compared with the CIA model group, SIN significantly ameliorated swelling and erythema extension, decreased the arthritis index, reduced inflammation, cartilage damage and bone erosion, and lessened the number of CD31 positive cells on the synovium. Moreover, the levels of HIF-1α, VEGF and ANG-1 in the synovium and in the peripheral serum were increased in the untreated CIA model group but were significantly reduced in the 30 mg/kg, 100 mg/kg and 300 mg/kg SIN treatment groups.
SIN could mitigate CIA by inhibiting angiogenesis, and the mechanism may associate with the HIF-1α–VEGF–ANG-1 axis. Additionally, our study provides a referable experimental basis for the use of SIN for the treatment of rheumatoid arthritis.
•High-intensity ultrasound caused oxidation and aggregation of shrimp MP.•High-intensity ultrasound improved functional properties of shrimp MP.•High-intensity ultrasound improved gelling properties ...of shrimp MP.•High-intensity ultrasound enhanced viscoelasticity of shrimp-based surimi.
The effects of high-intensity ultrasound on the physicochemical and gelling properties of Litopenaeus vannamei (L. vannamei) myofibrillar protein (MP) were investigated. MP solutions were subjected to ultrasound treatment (power 100 W, 300 W, and 500 W). It was found that the carbonyl and free amino contents of MP increased significantly with increasing ultrasound power, accompanied by enhanced emulsification properties. The increase of free radical and carbonyl content indicated that ultrasound induced the oxidation of MP. With the increase of ultrasound power, it was found that the total sulfhydryl content of the shrimp MP decreased, but the surface hydrophobicity increased significantly, which might be closely related to the conformational changes of MP. Meanwhile, a significant increase of β-sheet but a decrease of α-helix in the secondary structure of MP was observed with increasing ultrasound power, indicating that ultrasound treatment induced the stretching and flexibility of MP molecules. SDS-PAGE showed that L. vannamei MP consisted of myosin heavy chain, actin, myosin light chain, paramyosin and tropomyosin. Ultrasound treatment could lead to some degree of oxidative aggregation of MP. The results of rheological properties indicated that ultrasound treatment enhanced the viscoelasticity of MP and further improved the gel strength of MP gel. This study can provide a theoretical basis for the functional modification of shrimp MP and the processing of its surimi products.
Previous studies implied that dietary isoflavone intake may reduce the risk of developing breast cancer, but some have shown ambiguous results. This study aimed to systematically evaluate and ...summarize available evidence on the effect dietary isoflavone intake has on the risk of developing breast cancer.
PubMed, Embase, and the Cochrane Library were searched for prospective cohort studies published through April 2017 that evaluated the effect of dietary isoflavone intake on the development of breast cancer.
Sixteen prospective cohort studies, involving 11,169 breast cancer cases and 648,913 participants, were identified and included in our data analysis. The pooled relative risk (RR) of breast cancer was 0.99 for high versus low intake of isoflavones (95% confidence interval CI, 0.91–1.09; P = 0.876) and 0.99 for moderate versus low intake of isoflavones (95%CI, 0.92–1.05; P = 0.653), with insignificant heterogeneity (P = 0.187 for high versus low, and P = 0.192 for moderate versus low). While a moderate consumption of soy-based foods did not significantly affect breast cancer risk, a high intake of soy-based foods associated with a lower risk of developing breast cancer. Considering specific foods, an increased the risk of developing breast cancer was seen with a moderate intake of formononetin, but no significant associations were found between breast cancer risk and other isoflavone-rich diets.
The present meta-analysis indicates that women with a high dietary intake of soy foods may experience a statistically significant reduction in breast cancer risk. However, moderate formononetin consumption may increase the risk of developing breast cancer.
Leaf-color is an effective marker to identify the hybridization of rice. Leaf-color related genes function in chloroplast development and the photosynthetic pigment biosynthesis of higher plants. The ...ygl7 (yellow-green leaf 7) is a mutant with spontaneous yellow-green leaf phenotype across the whole lifespan but with no change to its yield traits. We cloned gene Ygl7 (Os03g59640) which encodes a magnesium-chelatase ChlD protein. Expression of ygl7 turns green-leaves to yellow, whereas RNAi-mediated silence of Ygl7 causes a lethal phenotype of the transgenic plants. This indicates the importance of the gene for rice plant. On the other hand, it corroborates that ygl7 is a non-null mutants. The content of photosynthetic pigment is lower in Ygl7 than the wild type, but its light efficiency was comparatively high. All these results indicated that the mutational YGL7 protein does not cause a complete loss of original function but instead acts as a new protein performing a new function. This new function partially includes its preceding function and possesses an additional feature to promote photosynthesis. Chl1, Ygl98, and Ygl3 are three alleles of the OsChlD gene that have been documented previously. However, mutational sites of OsChlD mutant gene and their encoded protein products were different in the three mutants. The three mutants have suppressed grain output. In our experiment, plant materials of three mutants (ygl7, chl1, and ygl98) all exhibited mutational leaf-color during the whole growth period. This result was somewhat different from previous studies. We used ygl7 as female crossed with chl1 and ygl98, respectively. Both the F1 and F2 generation display yellow-green leaf phenotype with their chlorophyll and carotenoid content falling between the values of their parents. Moreover, we noted an important phenomenon: ygl7-NIL's leaf-color is yellow, not yellowy-green, and this is also true of all back-crossed offspring with ygl7.
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