Amentoflavone impairs the reconsolidated fear memories through inhibition of ERK pathway.

Post-traumatic stress disorder (PTSD) is a pathological fear memory-related disease. The persistence of pathological fearful memories is one of the most characteristic symptoms of PTSD. However, this can be eliminated by intervening in reconsolidation. Inflammation is intimately involved in the pathophysiologic progression of PTSD. Amentoflavone (AF) has anti-inflammatory effects. However, the effect of AF on fear memory reconsolidation remains unclear. In the present series of experiments, the CFC paradigm of rats were constructed. This was followed by AF administration immediately after exposure to the conditioning chamber to observe the maintenance of fear memory. Finally, a Western blot for the amygdala was used to explore the possible molecular biological mechanisms of AF affecting animal behavior. The findings suggest that re-exposure to the conditioning chamber for retrieval of CFC memory followed by immediate intragastric AF administration in rats attenuated the fear response for at least 14 days. In addition, the Western blot results show that the CFC memory intervention effect of AF administration during the reconsolidation phase may be related to the ERK signaling pathway inhibition. In general, the administration of AF in the reconsolidation phase to inhibit neuroinflammation can block the reconsolidation process and disrupt fear memory retention in the long term, at least in part through ERK pathway.

Quantification, morphology and source of humic acid, kerogen and black carbon in offshore marine sediments from Xiamen Gulf, China.

Three types of macromolecular organic matters (MOMs), i.e. humic acid (HA), kerogen+black carbon (KB), and black carbon (BC) were extracted from marine sediments of Xiamen Gulf, southeast of China. The chemical composition, morphological property and source of the three extractions were characterized by elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) and scanning electron microscope (SEM). The results showed that KB was the predominant fraction in MOMs, which accounted for 61.79%-89.15% of the total organic content (TOC), while HA consisted less than 5%. The relative high contents of kerogen and BC, and low contents of HA in the samples indicated that anthropogenic input might be the major source of organic matter in marine sediments near the industrial regions. The characterization of SEM, not only revealed morphological properties of the three fractions, but also allowed a better understanding of the source of MOMs. The delta13C values of the three fractions suggested that materials from terrestrial C3 plants were predominant. Furthermore, the anthropogenic activities, such as the discharge of sewage, coal and biomass combustion from industry nearby and agricultural practices within drainage basin of the Jiulong River, were remarkably contributed to the variations in delta13C values of MOMs in the offshore marine sediments.

Identification of Serum miR-501-3p and miR-338-3p as Novel Diagnostic Biomarkers for Breast Cancer and Their Target Genes Associated with Immune Infiltration.

Background: MicroRNAs influence the growth and metastasis of breast cancer (BC) by regulating their target genes. Our study aims to screen and identify miRNAs that are closely related to the development of breast cancer, and explore the role of these miRNAs and their target genes in breast cancer. Methods: Bioinformatics tools were applied to screen breast cancer-associated miRNAs and predict their potential target genes. Serum miRNAs were measured using RT-PCR. The correlation between miRNA expression and different clinicopathological features of BC patients was analyzed. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value. GEPIA, Kaplan-Meier Plotter, TIMER, and TISIDB databases were used to validate the expression levels and their prognostic value, as well as their target gene associated with immune infiltrating cells and immune checkpoints. Results: Breast cancer-associated serum miR-338-3p and miR-501-3p were screened and verified for the first time. Serum miR-501-3p was elevated in BC and was closely linked to the ki-67 index and histological grade. CDKN2C, as a potential target gene of miR-501-3p, was enriched in the cGMP-PKG signaling pathway. Serum miR-338-3p was reduced in BC and was strongly linked to lymph node metastasis and histological grading. ACTR2, CDH1, COL1A1, RBBP5, RRM1, and TPM3, as potential target genes of miR-338-3p, were enriched in MAPK, PI3K-Akt, and RAS signaling pathways. These target genes were found to be linked to breast cancer prognosis, immune infiltrating cells, and immune checkpoint inhibitors. Analysis of ROC curve showed that serum miR-501-3p combined with serum miR-338-3p had a high diagnostic value in breast cancer (AUC: 0.89, 95% CI: 0.821-0.958). Conclusion: Serum miR-501-3p combined with serum miR-338-3p show obvious clinical significance in the diagnosis and prognosis of breast cancer, which suggests that they may act as novel diagnostic biomarkers for breast cancer.

One-year measurement of organic and elemental carbon in size-segregated atmospheric aerosol at a coastal and suburban site in Southeast China.

To understand the influence of the urbanization process on the air quality in the urban neighbourhood area, the size distribution and seasonal variations of elemental and organic carbon in aerosols were studied at a coastal and suburban site in Xiamen City, China. A total of 87 samples were obtained during the one-year measurement campaign from June 2009 to May 2010. The results indicated that 79.3 ± 3.2% of the organic carbon (OC) and 88.3 ± 1.7% of the elemental carbon (EC) were associated with fine particles (PM(2.5)), which consist of 32.0 ± 8.3% of the total carbonaceous aerosol (TCA). The concentrations of the OC and EC in PM(2.5) were 17.8 ± 11.2 and 3.8 ± 1.9 µg m(-3), respectively, and high concentrations were usually observed when the wind direction was northeast (NE). High OC/EC ratios (average 5.1) in PM(2.5) indicated the formation of secondary organic carbon (SOC), which contributed 60.0% to the OC and 11.0% to the particulate matter. At this site, SOC had a significant negative correlation with the temperature (R(2) = 0.42), and a favorable meteorological condition for SOC formation was found in the wintertime. The OC/EC ratios increased with particle size, while the fractions of the carbonaceous aerosols to particulate matter decreased. OC, EC and SOC concentrations and OC/EC ratios followed the same seasonal pattern of winter > spring > autumn > summer, which mainly resulted from the various origins of the air masses in different seasons. This study indicates the requirement for mitigating the pollution of carbonaceous aerosol at this coastal and suburban area in Xiamen City.

Chemical compositions of PM2.5 aerosol during haze periods in the mountainous city of Yong'an, China.

Haze phenomena were found to have an increasing tendency in recent years in Yong'an, a mountainous industrial city located in the center part of Fujian Province, China. Atmospheric fine particles (PM2.5) in the urban area during haze periods in three seasons (spring, autumn and winter) from 2007 to 2008 were collected, and the mass concentrations and chemical compositions (seventeen elements, water soluble inorganic ions (WSIIs) and carbonaceous species) of PM2.5 were determined. PM2.5 mass concentrations did not show a distinct difference among the three seasons. The carbonaceous species organic carbon (OC) and elemental carbon (EC) constituted up to 19.2%-30.4% of the PM2.5 mass during sampling periods, while WSIIs made up 25.3%-52.5% of the PM2.5 mass. The major ions in PM2.5 were SO4(2-), NO3(-) and NH4(+), while the major elements were Si, K, Pb, Zn, Ca and Al. The experimental results (from data based on three haze periods with a 10-day sampling length for each period) showed that the crustal element species was the most abundant component of PM2.5 in spring, and the secondary ions species (5O4(2-), NO3(-), NH4(+), etc.) was the most abundant component in PM2.5 in autumn and winter. This indicated that dust was the primary pollution source for PM2.5 in spring and combustion and traffic emissions could be the main pollution sources for PM2.5 in autumn and winter. Generally, coal combustion and traffic emissions were considered to be the most prominent pollution sources for this city on haze days.

Deactivation mechanism and feasible regeneration approaches for the used commercial NH3-SCR catalysts.

The deactivation and regeneration of selective catalytic reduction catalysts which have been used for about 37,000 h in a coal power plant are studied. The formation of Al2(SO4)3, surface deposition of K, Mg and Ca are primary reasons for the deactivation of the studied Selective catalytic reduction catalysts. Other factors such as activated V valence alteration also contribute to the deactivation. Reactivation of used catalysts via environment-friendly and finance-feasibly approaches, that is, dilute acid or alkali solution washing, would be of great interest. Three regeneration pathways were studied in the present work, and dilute nitric acid or sodium hydroxide solution could remove most of the contaminants over the catalyst surface and partly recover the catalytic performance. Notably, the acid-alkali combination washing, namely, catalysts treated by dilute sodium hydroxide and nitric acid solutions orderly, was much more effective than single washing approach in recovering the activity, and NO conversion increased from 23.6% to 89.5% at 380°C. The higher removal efficiency of contaminants, the lower dissolution of activated V, and promoting the formation of polymeric vanadate should be the main reason for recovery of the activity.

Pattern of atmospheric mercury speciation during episodes of elevated PM2.5 levels in a coastal city in the Yangtze River Delta, China.

Measurement of atmospheric mercury speciation was conducted in a coastal city of the Yangtze River Delta, China from July 2013 to January 2014, in conjunction with air pollutants and meteorological parameters. The mean concentrations of gaseous elemental mercury (GEM), particulate bound mercury (HgP) and reactive gaseous mercury (RGM) were 3.26 ± 1.63 ng m-3, 659 ± 931 pg m-3, and 197 ± 246 pg m-3, respectively. High percentages of HgP during haze days were found, due to the increase in direct emissions and gas-particle partitioning of RGM. The average gas-particle partitioning coefficients (Kp) during moderate or severe haze days (PM2.5 > 150 µg m-3) were obviously decreased. GEM and HgP were positively correlated with PM2.5, SO2, NO2 and CO, suggesting a significant contribution of anthropogenic sources. Elevated HgP concentrations in cold seasons and in the morning were observed while RGM exhibited different seasonal and diurnal pattern. The ratio of HgP/SO2 and Pearson correlation analysis suggested that coal combustion was the main cause of increasing atmospheric Hg concentrations. The monitoring site was affected by local, regional and interregional sources. The back trajectory analysis suggested that air mass from northwest China and Huabei Plain contributed to elevated atmospheric Hg in winter and autumn, while southeast China with clean air masses were the major contributor in summer.

Characteristics and sources of atmospheric mercury speciation in a coastal city, Xiamen, China.

Semi-continental monitoring of gaseous elemental mercury (GEM), particulate mercury (Hgp), and reactive gaseous mercury (RGM) was conducted in the Institute of Urban Environment, CAS in Xiamen, China from March 2012 to February 2013. The average concentrations and relative standard deviations (RSD) were 3.50 (34.6%) ng m(-3), 174.41 (160.9%) pg m(-3), and 61.05 (113.7%) pg m(-3) for GEM, Hgp, and RGM, respectively. The higher concentrations of GEM and Hgp were observed in spring and winter months, indicating the combustion source, while RGM showed the different seasonal variation with highest concentration in spring and the minimum value in winter. The concentrations of Hg species were generally elevated in nighttime and low in daytime to reflect the diurnal changes in meteorology, especially the mixing condition of the air masses. The high Hg concentrations were observed in SWW-NW sectors due to calm wind while the low levels in NE-SE due to high speed wind, and the amplitude was much larger for Hgp and RGM. Backward trajectories calculation indicated that summer air masses were much more from ocean with lower Hg while the air masses were mainly from inland area in other seasons. Principal component analysis suggested that combustion and road traffic emissions were the dominant anthropogenic mercury sources for the study area, and the temporal distribution of atmospheric mercury was mainly the result of climatological change.

Effects of urbanization on gaseous and particulate polycyclic aromatic hydrocarbons and polychlorinated biphenyls in a coastal city, China: levels, sources, and health risks.

Gas/particle distributions of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were measured in Xiamen from May 2009 to March 2010 to evaluate the impacts of urbanization on the fate of persistent organic pollutants (POPs) in the atmospheric environment. In a newly developing area (NDA), the concentrations of 16 PAHs (gas + particle) were significantly higher than that a historically urbanized area (HUA) (p value <0.05), while the trend of 28 PCBs was reversed. Diagnostic ratios and principle component analysis (PCA) implied that atmospheric PAHs in the NDA were mainly derived from petrogenic combustion, including mixed sources of vehicle emissions, biomass burning and oil combustion, while pyrogenic combustion (e.g., traffic and coal combustion) was considered the major source of PAHs in the HUA. Atmospheric PCBs in both HUA and NDA were dominated by TriCBs and PeCBs related to the use of commercial mixtures (Aroclors 1242 and 1254). Based on the toxicological equivalent factor (TEF) approach, total benzo[a]pyrene equivalent values in the HUA and NDA were 1.12 and 2.02 ng m(-3), respectively, exceeding the standard threshold values (1.0 ng m(-3)) of China and WHO. Average daily intake of dioxin-like compounds was 0.2 pg kg(-1) day(-1) in the HUA, which are below the WHO tolerable daily intake level. The results showed that the contribution to the toxic equivalency (TEQ) was dominated by PCB169, PCB105, and PCB81.

[Pollution characteristics of platinum group elements in road rust in Xiamen].

With the potential risks for the environment and human health, the concentration and distribution characteristics of platinum group element(PGEs) in road dust in Xiamen city were investigated. Road dust samples were collected from the traffic trunk road, tunnel, tourism area, and industrial area of Xiamen on October 2012. The samples were digested with aqua regia in a microwave assisted digestion system under high pressure condition, separated and purified with cation exchange resin( Dowex AG50W-X8), and the resulting solutions were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the average concentrations(range) of Pd, Pt and Rh in road dust were 246.82 (58.68-765.52) ng x g(-1), 95.45 (42.14-371.36) ng x g(-1) and 51.76 (21.04-119.72) ng x g(-1), respectively, which were two orders of magnitude higher than the background values. Compared with other cities worldwide, the concentrations of Pd, Pt and Rh in road dust in Xiamen were at higher levels. Theconcentrations of PGEs for different functional areas were listed in the following order: tunnel > urban district > industrial area > tourism area, which indicated that their spatial distributions were mainly affected by the traffic intensity. Correlation analysis results showed that concentration of Pd in the urban traffic artery was significantly correlated with Rh, while Pt was not so correlated with Pd and Rh, suggesting that other sources contributed to PGEs in road dust in addition to the vehicle emission. Although motor vehicle traveling was banned in tourist area, the concentration of PGEs was still at a high level. Some of them might originate from the road dust in surrounding area by atmosphere diffusion.

Quantitative analysis of influencing factors to aerosol pH and its responses to PM2.5 and O3 pollution in a coastal city.

Aerosol acidity (pH) plays an important role in the multiphase chemical processes of atmospheric particles. In this study, we demonstrated the seasonal trends of aerosol pH calculated with the ISORROPIA-II model in a coastal city of southeast China. We performed quantitative analysis on the various influencing factors on aerosol pH, and explored the responses of aerosol pH to different PM2.5 and O3 pollution levels. The results showed that the average aerosol pH was 2.92 ± 0.61, following the order of winter > spring > summer > autumn. Sensitivity tests revealed that SO42-, NHx, T and RH triggered the variations of aerosol pH. Quantitative analysis results showed that T (37.9%-51.2%) was the main factors affecting pH variations in four seasons, followed by SO42- (6.1%-23.7%), NHx (7.2%-22.2%) and RH (0-14.2%). Totally, annual mean meteorological factors (52.9%) and chemical compositions (41.3%) commonly contributed the aerosol ΔpH in the coastal city. The concentrations of PM2.5 was positively correlated with aerosol liquid water content (R2 = 0.53) and aerosol pH (R2 = 0.26), indicating that the increase in pH was related with the elevated NH4NO3 and decreased SO42-, and also the changes of T and RH. The Ox (O3 + NO2) was moderately correlated with aerosol pH (R2 = -0.48), attributable to the fact that the proportion of SO42- increased under high T and low RH conditions. The study strengthened our understanding of the contributions of influencing factors to aerosol pH, and also provided scientific evidences for chemical processes of atmospheric particles in coastal areas.

Characteristics of water-soluble inorganic ions in PM2.5 and PM 2.5-10 in the coastal urban agglomeration along the Western Taiwan Strait Region, China.

PM2.5 and PM2.5-10 aerosol samples were collected in four seasons during November 2010, January, April, and August 2011 at 13 urban/suburban sites and one background site in Western Taiwan Straits Region (WTSR), which is the coastal area with rapid urbanization, high population density, and deteriorating air quality. The 10 days average PM2.5 concentrations were 92.92, 51.96, 74.48, and 89.69 µg/m(3) in spring, summer, autumn, and winter, respectively, exceeding the Chinese ambient air quality standard for annual average value of PM2.5 (grade II, 35 µg/m(3)). Temporal distribution of water-soluble inorganic ions (WSIIs) in PM2.5 was coincident with PM2.5 mass concentrations, showing highest in spring, lowest in summer, and middle in autumn and winter. WSIIs took considerable proportion (42.2 ∼ 50.1 %) in PM2.5 and PM2.5-10. Generally, urban/suburban sites had obviously suffered severer pollution of fine particles compared with the background site. The WSIIs concentrations and characteristics were closely related to the local anthropogenic activities and natural environment, urban sites in cities with higher urbanization level, or sites with weaker diffuse condition suffered severer WSIIs pollution. Fossil fuel combustion, traffic emissions, crustal/soil dust, municipal constructions, and sea salt and biomass burnings were the major potential sources of WSIIs in PM2.5 in WTSR according to the result of principal component analysis.

[Characterization of organic carbon (OC) and elemental carbon (EC) in PM2.5 during the winter in three major cities in Fujian province, China].

PM2.5 samples were collected in three cities (Fuzhou, Xiamen and Quanzhou) in Fujian Province, China, during the winter, and were analyzed for organic carbon (OC) and elemental carbon (EC) by thermal optical transmission (TOT). The characteristics such as pollution levels and spatial distributions of PM2.5, OC and EC, correlations between OC and EC, OC/EC ratios and secondary organic carbon (SOC) were discussed in details. Average concentrations of PM2.5 were ranged from (79.94 +/- 18.08) microg(-3) to (114.78 +/- 26.10) microg x m(-3), which were in excess of the Ambient Air Quality Standards (GB 3095-2012) 24-hr mass-based standards of 75 microg x m(-3). Averages concentrations of OC and EC were fluctuated from (14.77 +/- 2.65) microg x m(-3) to (19.27 +/- 1.96) microg x m(-3) and (1.99 +/- 0.50) microg x m(-3) to (3.36 +/- 0.41) microg x m(-3), respectively, which were 1.2 to 1.6 times and 1.2 to 2.0 times more than that in the background site, Pingtan in Fuzhou. Correlations between OC and EC in PM2.5 were found to be strong in Pingtan (R2 = 0.70) and Jin'an (R2 = 0.66) (Fuzhou) , suggesting that there were similar primary pollutants of OC and EC. Average OC/EC ratios were 5.64-7.71 and all higher than 2, which indicated that the secondary organic carbon (SOC) was formed. The estimated concentrations of SOC were from 2.47 microg x m3 to 7.17 microg x m(-3), which contributed 13.08%-45.67% to the OC and 2.20%-7.78% to PM2.5.

Spatial distribution and sources identification of elements in PM2.5 among the coastal city group in the Western Taiwan Strait region, China.

The main purpose of this study was to investigate the spatial variations of 20 elements (Al, Si, Ti, Ca, Fe, Mg, Cr, Mn, Ni, P, S, K, Cu, Cl, V, Se, Br, As, Zn, and Pb) in PM(2.5) (particle matters ≤ 2.5 µm in aerodynamic diameter) in the coastal city group in the Western Taiwan Strait (WTS) region, China during spring 2011. The average PM(2.5) mass concentration at 13 sites was 77.0 µg/m(3) and the elemental fraction accounted for about 10-20%. Multivariate analyses (principal component analysis and cluster analysis) and a correlation matrix were used to identify the sources of elements in PM(2.5). The results revealed that the elements originated mainly from traffic emissions, coal combustion, pyrometallurgical processes, and crustal sources. Spatially, the concentrations of elements were generally higher in several rapidly growing locations, and the enrichment factors (EFs) for most elements were much higher at the northern sites than those at the southern sites, suggesting that the air quality in the northern part of the study area was strongly affected by anthropogenic activity. Backward wind trajectory analysis during the sampling period indicated that the concentrations of elements in PM(2.5) in the WTS region were greatly impacted by dust particles transported from Northern China in spring.

Source contributions to carbonaceous species in PM2.5 and their uncertainty analysis at typical urban, peri-urban and background sites in southeast China.

Determination of (14)C and levoglucosan can provide insights into the quantification of source contributions to carbonaceous aerosols, yet there is still uncertainty on the partitioning of organic carbon (OC) into biomass burning OC (OCbb) and biogenic emission OC (OCbio). Carbonaceous species, levoglucosan and (14)C in PM2.5 were measured at three types of site in southeast China combined with Latin hypercube sampling, with the objectives to study source contributions to total carbon (TC) and their uncertainties, and to evaluate the influence of levoglucosan/OCbb ratios on OCbb and OCbio partitioning. It was found reliably that fossil fuel combustion is the main contributor (62.90-72.23%) to TC at urban and peri-urban sites. Biogenic emissions have important contribution (winter, 52.98%; summer, 45.71%) to TC at background site. With the increase in levoglucosan/OCbb ratios, the contribution of OCbio is increased while OCbb is decreased in a pattern of approximate natural logarithm at a given range.

Mercury distribution in seawater discharged from a coal-fired power plant equipped with a seawater flue gas desulfurization system.

BACKGROUND AND PURPOSE: More and more coal-fired power plants equipped with seawater flue gas desulfurization systems have been built in coastal areas. They release large amount of mercury (Hg)-containing waste seawater into the adjacent seas. However, very limited impact studies have been carried out. Our research targeted the distribution of Hg in the seawater, sediment, biota, and atmosphere, and its environmental transportation. METHODS: Seawater samples were collected from five sites: 1, sea areas adjacent to the power plant; 2, near discharge outlets; 3, the aeration pool of the power plant; and 4 and 5, two reference sites. The total gaseous Hg was determined in situ with a Tekran 2537B. Analyses of total Hg (TM) followed the USEPA methods. RESULTS: In most part of the study area, TM concentrations were close to the reference values and Hg transfer from the seawater into the sediment and biota was not obvious. However, in the aeration pool and near the waste discharge outlets, atmospheric and surface seawater concentrations of TM were much higher, compared with those at a reference site. The concentration ranges of total gaseous Hg and TM in seawater were 3.83-8.60 ng/m(3) and 79.0-198 ng/L near the discharge outlets, 7.23-13.5 ng/m(3) and 186-616 ng/L in the aeration pool, and 2.98-4.06 ng/m(3) and 0.47-1.87 ng/L at a reference point. CONCLUSIONS: This study suggested that the Hg in the flue gas desulfurization waste seawater was not only transported and diluted with sea currents, but also could possibly be transferred into the atmosphere from the aeration pool and from the discharge outlets.

[Determination of sulfite in flue gas desulfurization with seawater by ion chromatography].

The technology for flue gas desulfurization (FGD) with seawater is widely adopted by coal-fired power plants in coastal areas. SO2 in the flue gas is absorbed by alkaline seawater and transfered in aqueous phase as sulfite (SO3(2-)), and most SO3(2-) is transformed to sulfate (SO4(2-)) after an aeration process. The remaining SO3(2-) in the seawater discharged to sea area may be harmful to marine organism because of its biological toxicity, thus it is necessary to determine the concentration of SO3(2-) in the seawater for desulfurization. In this study, the method of determination of SO3(2-) in the seawater by ion chromatography was investigated. The separation was achieved on an IonPac AS14A column with 14 mmol/L NaOH-12 mmol/L Na2 CO3 solution as the mobile phase at a flow rate of 1.2 mL/min, and the detection was performed by a pulsed amperometric detector. Formaldehyde was added as a protective agent when sampling because the SO3(2-) is easy to be oxidized. To avoid the formation of Mg (OH)2 in the mobile phase with high pH value which might block the column, the Mg(2+) in seawater was precipitated by NaOH solution (pH 12.0) before sample determination. The method showed good linearity within the range of 0-100 mg/L with an average recovery of 116.8%. The method detection limit (MDL) reached as low as 0.05 mg/L. The relative standard deviations (RSD) for seawater matrix samples spiked at levels of 7.5, 25.0 and 75.0 mg/L were 2.1% 3.1% and 4.0% (n = 9) , respectively. The method has been applied for the determination of SO3(2-) in flue gas desulfurization seawater with the advantages of being fast, sensitive and selective.