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Several explanations have been proposed for the rapid spread of Solidago canadensis in various environments. Yet, the specific role of soil prokaryotes in this process remains unclear. To understand the prokaryotic role, we conducted a field study in eastern China, where S. canadensis invaded the native plant Humulus scandens. Prokaryotic communities in the soil were studied across three levels of invasion intensity: low, medium, and high (S. canadensis less than 10, about 50, and above 90%, respectively). We found that the S. canadensis invasion decreased the total prokaryotic abundance in the bulk soil (1.61 ± 0.57 × 108 to 5.78 ± 3.65 × 107 copies g−1 DW), but increased the total prokaryotic abundance in S. canadensis (7.72 ± 5.11 × 107 to 1.27 ± 0.71 × 108 copies g−1 DW) and H. scandens rhizosphere (1.11 ± 0.28 × 108 to 1.79 ± 0.68 × 108 copies g−1 DW). S. canadensis invasion enhanced nutrient-releasing microorganisms (Actinobacteria) (p < 0.05) and disease-resistant microorganisms (Nocardioides) (p < 0.05), while decreasing N-cycling microorganisms (Thaumarchaeota and Nitrospirae) (p < 0.05). This study suggests that S. canadensis may enhance its invasion by modulating the species and relative abundance of functional microorganisms in the bulk soil. [Display omitted] • S. canadensis invasion decreased prokaryotic abundance in bulk soil but increased prokaryotic abundance in plant rhizospheres. • S. canadensis promoted plant growth promoting and disease-resistant microorganisms. • S. canadensis invasion decreased nitrifying microorganisms in soil. [ABSTRACT FROM AUTHOR]

Environmental contamination caused by various pollutants due to automobile emissions is an alarming issue. One important type of the pollutants are heavy metals, including chromium (Cr) added by the exhaust of toxic smoke of vehicles. These pollutants are added to forage crops cultivated near roadsides, soil and irrigation water. However, rare studies have been conducted to infer Cr accumulation near heavy automobile emission areas. This study was conducted to determine Cr concentration in irrigation water, soil and forage. Water, forage and soil samples were collected from area impacted by heavy traffic. Atomic absorption spectrophotometer was used to appraise Cr values in the collected samples. Chromium values ranged from 0.50 to 1.14 mg/kg in water samples and from 0.04 to 2.23 mg/kg in soil samples. It was highest in Zea mays grown soil, whereas minimum in Brassica campestris soil. The Cr values in forages ranged from 0.09 to 1.06 mg/kg. Z. mays observed the highest Cr accumulation, whereas the lowest Cr accrual was noted for B. campestris. The pollution load index (PLI) was the highest for Trifolium alexandrinum , while the lowest for Z. mays. Bio-concentration factor (BCF) ranged from 0.14 to 8.63. The highest BCF was noted for T. alexandrinum , while the lowest for Z. mays. The highest and the lowest daily intake of metal (DIM) was noted for Z. mays at different sites. Health risk index (HRI) was highest for Z. mays and lowest for B. campestris. The results add valuable information on heavy metal accumulation in water, soil and forage samples near to automobile emission area. [ABSTRACT FROM AUTHOR]

Cadmium contamination in croplands is recognized one of the major threat, seriously affecting soil health and sustainable agriculture around the globe. Cd mobility in wastewater irrigated soils can be curtailed through eco-friendly and cost effective organic soil amendments (biochars) that eventually minimizes its translocation from soil to plant. This study explored the possible effects of various types of plants straw biochar as soil amendments on cadmium (Cd) phytoavailability in wastewater degraded soil and its subsequent accumulation in sunflower tissues. The studied biochars including rice straw (RS), wheat straw (WS), acacia (AC) and sugarcane bagasse (SB) to wastewater irrigated soil containing Cd. Sunflower plant was grown as a test plant and Cd accumulation was recorded in its tissues, antioxidant enzymatic activity chlorophyll contents, plant biomass, yield and soil properties (pH, NPK, OM and Soluble Cd) were also examined. Results revealed that addition of biochar significantly minimized Cd mobility in soil by 53.4%, 44%, 41% and 36% when RS, WS, AC and SB were added at 2% over control. Comparing the control soil, biochar amended soil effectively reduced Cd uptake via plants shoots by 71.7%, 60.6%, 59% and 36.6%, when RS, WS, AC and SB. Among all the biochar, rice husk induced biochar significantly reduced oxidative stress and reduced SOD, POD and CAT activity by 49%, 40.5% and 46.5% respectively over control. In addition, NPK were significantly increased among all the added biochars in soil–plant system as well as improved chlorophyll contents relative to non-bioachar amended soil. Thus, among all the amendments, rice husk and wheat straw biochar performed well and might be considered the suitable approach for sunflower growth in polluted soil. [ABSTRACT FROM AUTHOR]

• Widespread metasomatism following partial melting events in the studied peridotites. • Pervasive hydrogen diffusional loss in both olivine and pyroxene. • Orthopyroxene more likely preserves its in-situ water contents than clinopyroxene. • H partitioning between pyroxene of ∼2 doesn't indicate equilibrium partitioning. Water is key to many geodynamical processes in the Earth's upper mantle, yet its preservation in mantle minerals is still debated. To throw some light on this problem, we here carried out an integrated study of whole-rock and mineral chemistry, and hydrogen concentrations in olivine, orthopyroxene, and clinopyroxene within 18 spinel lherzolite samples from three localities (Lianshan, Panshishan, and Tashan) in the Nanjing area, eastern China. Whole-rock and mineral compositions suggest that the studied peridotite samples interacted with melt at different melt/rock ratios following various degrees of partial melting (up to 11%). Fourier transform infrared (FTIR) measurements show that olivine is almost dry (<1 wt ppm H 2 O) while the cores of orthopyroxene and clinopyroxene contain 14–151 wt ppm H 2 O and 41–218 wt ppm H 2 O, respectively. Profile analyses of >70 orthopyroxene grains, which are homogeneous in major-element compositions, covering all the studied samples show hydrogen-depleted rims, indicative of hydrogen diffusional loss. This hydrogen zonation is probably caused by hydrogen chemical diffusion controlled by the mobility of trivalent cations (most likely Al3+) in response to magma degassing or partial melting of peridotite during ascent, or interactions of peridotite with melt, or a combination of these processes. By contrast, no hydrogen zonation is observed in clinopyroxene. Based upon the comparison of chemical compositions (especially Fe and AlIV contents) of clinopyroxene within our samples with those in diffusion experiments, it is inferred that the hydrogen diffusivity in clinopyroxene should be larger than that in orthopyroxene from our samples. This inference points to that clinopyroxene within the studied samples must have experienced diffusional loss of hydrogen as well, suggesting that water concentrations in the lithospheric mantle beneath the study area are probably underestimated. Furthermore, it also implies that orthopyroxene instead of clinopyroxene most likely preserves the in-situ water concentrations at depth, at least at its core. The absence of hydrogen zonation in clinopyroxene can be attributed to its fine-grained nature and fast hydrogen diffusivity. Our FTIR data also show that Lianshan and Tashan samples have water concentration ratio between clinopyroxene and orthopyroxene (RCpx/Opx) of ∼2, similar to mantle xenoliths from eastern China and other localities worldwide, yet Panshishan samples have higher RCpx/Opx values (2.3–5.9). Since hydrogen loss is suggested for both pyroxenes, RCpx/Opx of ∼2 thus cannot be taken as a reliable indicator of preservation of original water concentration of mantle source and equilibrium partitioning of hydrogen between pyroxene, as opposed to previous suggestions. [ABSTRACT FROM AUTHOR]

Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants in the world but it is also a pollutant of global concern. In the present study, we studied the transformation of 14 C-labeled TBBPA by a polychlorinated-biphenyl-degrading bacterium, Rhodococcus jostii RHA1 (RHA1), under oxic conditions. During the 5-day incubation, TBBPA was biotransformed rapidly first to its monomethyl ether MeO-TBBPA and then to its more hydrophobic but less toxic dimethyl ether diMeO-TBBPA. The biotransformation followed pseudo-first-order decay kinetics, with a half-life of TBBPA of 0.32 days and only 0.6% of the initially added amount being mineralized. Considering the frequent co-occurrence of TBBPA with heavy metals in the natural environment, we also investigated the effects of three heavy metals (Cd, Cu, and Fe) on the transformation of TBBPA by strain RHA1. While TBBPA transformation was not significantly altered by Cd, it was accelerated by Cu and Fe, presumably due to the effects of these two essential metals on O -methyltransferase activity. Overall, the present study showed that RHA1 is an effective transformer of TBBPA and that certain essential metals, including Cu and Fe, promote the transformation. [ABSTRACT FROM AUTHOR]

Hybrid Broussonetia papyrifera (BP) has been widely planted and commonly used as ruminant forage source after fermentation in China. Very less information is available to know the impact of fermented BP on laying hens, thus, we have investigated effects of dietary supplementation of Lactobacillus plantarum -fermented B. papyrifera (LfBP) on laying performance, egg quality, serum biochemical parameters, lipid metabolism, and follicular development of laying hens. A total of 288 HY-Line Brown hens (age, 23 wk) were randomly assigned into 3 treatment groups: control group (Con, a basal diet), LfBP1 and LfBP5 group (a basal diet supplemented with 1% or 5% LfBP). Each group has 8 replicates of twelve birds each. The results demonstrated that dietary supplementation of LfBP increased average daily feed intake (linear, P < 0.05), feed conversion ratio (linear, P < 0.05), and average egg weight (linear, P < 0.05) during the entire experimental period. In addition, dietary inclusion of LfBP enhanced the egg yolk color (linear, P < 0.01) but decreased the eggshell weight (quadratic, P < 0.05) and eggshell thickness (linear, P < 0.01). In serum, the LfBP supplementation linearly decreased the content of total triglyceride (linear, P < 0.01) but increased the content of high density lipoprotein-cholesterol (linear, P < 0.05). The gene expression related to hepatic lipid metabolism including acetyl-CoA carboxylase, fatty acid synthase, and peroxisome proliferator-activated receptor (PPARα) was down-regulated whereas liver X receptor was up-regulated in LfBP1 group. Moreover, LfBP1 supplementation remarkably reduced the F1 follicle number and ovarian gene expression of reproductive hormone receptors including estrogen receptor, follicle stimulating hormone receptor, luteinizing hormone receptor, progesterone receptor, prolactin receptor, and B cell lymphoma-2. In conclusion, dietary inclusion of LfBP could improve feed intake, egg yolk color, and lipid metabolism, but may cause a decline in eggshell quality with higher inclusion level, herein, 1% is suggested. [ABSTRACT FROM AUTHOR]

Microorganisms in subtropical forest soils are responsible for various ecological functions such as decomposing organic matter and driving carbon and nitrogen cycles. It is essential to understand how environmental factors affect microbial community composition and diversity. Prokaryotic communities (including bacteria and archaea) were investigated according to soil layer (0–2 cm and 18–20 cm), forest type (mountain dwarf forest, Guangdong pine forest, and monsoon evergreen broadleaf forest) and season (summer and winter) in Guangdong Nanling National Natural Reserve in China by Miseq sequencing of 16S rRNA genes. This study reveals key factors that shaped prokaryotic community structure and diversity in subtropical forest soils in China. Results show that Acidobacteria and Proteobacteria were the dominant phyla, with a relative abundance of 54.2% and 20.7% respectively. Soil pH, organic matter, total N, hydrolysable N, available P, NO 3 −, and NH 4 + were significantly correlated with prokaryotic community structure and diversity. Soil layer significantly affected prokaryotic community structure and diversity. Forest type significantly influenced prokaryotic community structure but not diversity. Season did not significantly correlate with prokaryotic community structure or diversity. • Acidobacteria and Proteobacteria dominate subtropical forest soils. • Soil pH, SOM, TN, hydrolysable N, available P, NO 3 − and NH 4 + affect prokaryotes. • Soil layer affects prokaryotic community structure and diversity. • Forest type influences prokaryotic community structure but not diversity. • Season does not correlate with prokaryotic community structure or diversity. [ABSTRACT FROM AUTHOR]

Anaerobic methane oxidizing organisms, including sulfate dependent archaea (SAMO), nitrite dependent bacteria (n-damo), and nitrate archaea (n-damo), may collaborate with anaerobic ammonia oxidizers (anammox) bacteria in wetlands to remove inorganic nitrogen. The objective was to examine the structure and abundance of these organisms and their response to substrate inputs (sulfate, nitrate, or nitrite) in two wetlands of contrasting properties: a natural wetland and a constructed wetland to treat swine manure. No SAMO archaea were detected in either wetland. For n-damo bacteria, Ca. Methylomirabilis oxyfera dominated the natural wetland, while Clade 2 dominated the constructed wetland. For n-damo archaea, Clade 1 dominated the constructed wetland, while Clade 3 dominated the natural wetland. For anammox bacteria, Ca. Brocadia dominated both the natural wetland and the constructed wetland. Generally, the natural wetland contained higher gene abundance and more diversity of these three microorganisms than the constructed wetland, which could be due to high ammonium concentrations in the constructed wetland, forcing selections of genotypes to a narrow range of microorganisms. A slurry incubation experiment showed that both n-damo archaea and anammox bacteria increased over time in the constructed wetland sediment, indicating these two microorganisms might cooperate to complete the denitrification process from nitrate to dinitrogen gas. • n-damo bacteria, n-damo archaea, and anammox bacteria coexist in natural and constructed wetlands. • Natural wetland contained higher gene abundance and diversity of the microorganisms. • n-damo archaea and anammox bacteria cooperated to complete the denitrification in constructed wetland. [ABSTRACT FROM AUTHOR]

Abstract: A group of novel taxoids, with modifications at C-7, C-10, C-3′ and C-14 positions of paclitaxel, was synthesized in order to improve their biological profile by decreasing their affinity with P-glycoprotein (P-gp) and increasing cellular permeability. Most of the new taxoids demonstrated the similar potent cytotoxic activities in MCF-7 human tumor cell line as paclitaxel in vitro. In the permeability assay with monolayers of Caco-2 cells, most of the compounds demonstrated an increased trans-cellular transport in A-to-B direction in comparison with paclitaxel. Among them the compounds T-13, T-15 and T-26 showed the highest permeability, and with efflux ratios better than that of ortataxel. The interaction of the compounds T-13 and T-26 with P-gp was evaluated using Madin-Darby canine kidney (MDCK)-multidrug resistance-1(MDR1) and MDCK-wild-type (WT). The results indicated that T-13 and T-26 were poor substrates for P-gp and possessed inhibiting effects of P-gp mediated efflux. It was thus clear that simultaneous modifications at the C-7, C-10 and C-3′ positions of paclitaxel significantly impaired its interactions with P-gp and interfered with P-gp mediated efflux. [Copyright &y& Elsevier]

Abstract: Objective: To discuss the correlation between diffusion tensor imaging (DTI) measurements, diffusion tensor tractography and the clinical symptoms of cervical spondylotic myelopathy. Methods: Based on the Japanese Orthopedics Association (JOA) score, 104 cervical spondylotic myelopathy cases were first divided into four groups: mild, moderate, severe and serious groups. According to lesion signal characteristics, all cases were again divided into three groups: A(N/N): normal signal in both T1WI and T2WI; B (N/H): normal signal in T1WI but high signal in T2WI; and C (L/H): low signal in T1WI and high signal in T2WI. The apparent diffusion coefficient (ADC), fractional anisotropy (FA), λ1, λ2, and λ3 were measured and diffusion tensor tractography was performed in the seriously compressed section of the spinal cord. Results: The FA values were positively correlated with JOA scores (r =0.883, P <0.05), and significantly different among four JOA groups (P <0.05). The ADC, λ2, and λ3 were significantly different among the moderate, severe and serious groups as well as among the A, B, and C groups (P <0.05). Declining FA values were found associated with increasing fiber bundle damage. Conclusions: The FA values and the change patterns of fiber bundle were more sensitive than T2WI for spinal cord lesion, and were positively correlated with clinical symptoms. [Copyright &y& Elsevier]

Abstract: Canopy scale fluxes of isoprene and monoterpenes were investigated in both wet and dry seasons above a rubber tree (Hevea brasiliensis)/secondary tropical forest in the Yunnan province of southwestern China. Drought conditions were unusually high during the dry season experiment. The eddy covariance measurement technique was used to measure isoprene fluxes, while monoterpene fluxes were modeled based on leaf level emission measurements. Maximum observed isoprene fluxes occurred during the wet season and daytime average fluxes were about 1mg Cm-2h-1. Dry season fluxes were much lower with a daytime average of 0.15mg Cm-2h-1. Wet season isoprene fluxes compare quite well with isoprene fluxes observed from other tropical forests. Monoterpene fluxes came, almost entirely, from Hevea brasiliensis, which is a light-dependent monoterpene emitter. Modeled wet season total monoterpene fluxes were about 2mg Cm-2h-1 (average for the daytime), and in the dry season were undetectable. Extreme drought conditions, and the drought deciduous nature of Hevea brasiliensis may be the cause of the low dry season fluxes. [Copyright &y& Elsevier]

• Yonkenafil improved cognitive deficits in sporadic Alzheimer's disease rat model. • Yonkenafil inhibits the activation of microglia and astrocytes. • Yonkenafil reduced tau hyperphosphorylation via regulating JNK and GSK3β activation. Intracerebroventricular (icv) streptozotocin (STZ) injection decreases cerebral insulin signal pathway function and produces multiple effects that resemble the molecular, pathological, and behavioural features of Sporadic Alzheimer's disease (SAD). We previously reported that yonkenafil (yonk), the analogue of sildenafil and a novel PDE5 inhibitor exerts an anti-amyloidogenesis effect by regulating the Aβ level and inhibiting the expression of β-amyloid precursor protein in the APP/PS1 transgenic mice model. In this study, the effects of yonk on cognitive behaviors as well as the pathological features in streptozotocin-induced SAD rat model were investigated. The results demonstrated that administration of yonk at doses of 3 and 10 mg/kg for three weeks significantly improved cognitive deficits, attenuated STZ-induced neuronal death, inhibited the over-activation of microglia and astrocytes and the levels of pro-inflammatory markers, as well as decreased PDE5 protein expression in the hippocampus. Furthermore, yonk (3 mg/kg) notably prevented changes in tau hyperphosphorylation, decreased IRS-1and JNK phosphorylation and increased the GSK3β (ser9) phosphorylation induced by STZ. In summary, these data suggested that yonk significantly reversed STZ-induced memory deficits by inhibiting the over-activation of microglia and astrocytes, as well as ameliorated the levels of pro-inflammatory makers and tau hyperphosphorylation through regulating GSK3β signalling pathway. [ABSTRACT FROM AUTHOR]

Background The effects and safety of transradial access for stenting of carotid artery stenosis in patients with bovine-type and type III aortic arch are currently unknown and are the purpose of this study. Methods Patients who were treated with stenting via transradial (n = 28) compared with transfemoral (n = 30) access of carotid artery stenosis complicated with bovine-type and type III aortic arch were enrolled. The clinical data were studied for comparison. Results The success rate of transradial access for carotid artery stenting was 100%. During the transradial access procedure, 3 patients experienced a temporary blood pressure drop and bradycardia that was resolved with atropine injection. No radial artery occlusion or severe cardiac or cerebral events occurred. The success rate of transfemoral access for carotid artery stenting was 90% with failure in 3 patients. No complications occurred during or after the stenting procedure. The irradiation duration was significantly ( P = 0.001) smaller in transradial than in transfemoral access stenting (8.6 ± 0.87 vs. 11.4 ± 1.25 minutes). The arterial stenosis ranged 71.25%–96.50% (mean, 86.50% ± 10.15%) for transradial and 78%–97.75% (85.1% ± 10.42%) for transfemoral access groups before treatment, and the residual stenosis following treatment was significantly smaller in either the transradial (2.4%–17.75%; mean, 11.2% ± 6.03%) or transfemoral (4%–18.6%; mean, 12.4% ± 6.3%) groups compared with before treatment, respectively. Conclusions The transradial access for stenting of patients with type III aortic arch plus left carotid artery stenosis or in the bovine-type aortic arch combined with right carotid artery stenosis can decrease the stenting difficulty, risks of embolization, and radiation time and increase the success rate. [ABSTRACT FROM AUTHOR]