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Cadmium (Cd) is a common contaminant in aquatic environments. However, little is known about the mechanisms underlying Cd toxicity in the freshwater snail Cipangopaludina cathayensis (Heude, 1890). This study to investigate the toxic effects of Cd on the standard metabolism, antioxidant activities, immune function, and hepatopancreas transcriptome profiles of C. cathayensis. C. cathayensis was exposed to 0.25, 0.5, 1.0, or 1.5 mg/L Cd for 3 h, with results showing that Cd significantly inhibited oxygen consumption and ammonia excretion and disrupted the respiratory metabolism of C. cathayensis. In addition, the O:N ratio dropped below 7, indicating that C. cathayensis may rely exclusively on proteins as an energy source under Cd stress. To understand how Cd impacts the antioxidant activities, immune function, and transcriptional profiles, C. cathayensis were exposed to 0.5 (low exposure, L14) or 1.5 (high exposure, H14) mg/L Cd for 14 days. Our results indicate that Cd exposure leads to oxidative stress and immunosuppression, with the latter effect being larger for exposure to higher Cd concentrations. A total of 2172 differentially expressed genes (DEGs) were identified by transcriptome analysis of the hepatopancreas, of which 885 were upregulated and 1287 were downregulated. Gene ontology and KEGG analyses revealed that the DEGs in the H14 group are enriched for energy generation terms and the "oxidative phosphorylation" pathway, respectively. Therefore, up-regulation of energy metabolism may be an adaptive strategy under Cd stress. Moreover, several genes involved in antioxidant activity were downregulated, whereas genes related to reactive oxygen species generation were upregulated. In addition, many immunity-related genes were identified within the DEGs, indicating that Cd toxicity may affect immune defense. Further, DEGs in the H14 group were enriched for disease-associated pathways. Taken together, our results indicate that Cd exposure leads to metabolic disorders, oxidative stress, and immunosuppression and thus may potentially contribute to disease outbreaks. [Display omitted] • Cadmium exposure inhibited respiration and disturbed the metabolism of C. cathayensis. • Cadmium induced oxidative stress in C. cathayensis hepatopancreas. • Immunosuppression occurred after exposure to cadmium stress, potentially leading to disease outbreaks. • Differentially expressed genes related to metabolism, immune responses, and antioxidant activity were also identified. [ABSTRACT FROM AUTHOR]

It is evidenced that inflammation is involved in the pathogenesis of anxiety disorder, as well as the dysfunction of glutamate neurotransmission in the central nervous system (CNS). Chemokine CXCL12 has been reported taking part in the regulation of neurotransmitter release, however, the roles of CXCL12 in the development of anxiety are still unclear. In this study, we found that intraperitoneal (i.p) injection of lipopolysaccharide (LPS) induced anxiety-like behaviors in adult mice as measured by elevated plus-maze test (EPM) and open field test (OFT). Astrocytes were responsible for CXCL12 induction upon LPS challenge in hippocampus and amygdala, and microinjection of CXCL12 into amygdala induced mice anxiety-like behaviors. AMD3100, which is an antagonist for CXCL12 receptor CXCR4, prevented the anxiety behaviors induced by microinjection of CXCL12 into amygdala as well as injection i.p of LPS. Knockdown of CXCR4 expression in neurons using short hairpin RNAs (shRNAs) significantly blocked anxiety behaviors mediated by CXCL12 i.c injection. Furthermore, AMD3100 or shCXCR4 prevented the impairment of nesting ability induced by CXCL12 in mice. Whole-cell patch-clamp recordings in the neurons of basolateral amygdala (BLA) revealed that CXCL12 enhanced glutamatergic transmission by increasing sEPSC frequency in the amygdala. AMD3100 inhibited the excitatory glutamatergic neural transmission and involved in the development of anxiety through CXCR4. These findings provide direct evidence that alterations of CXCL12 in BLA play critical roles in the development of anxiety induced by systemic inflammation and that CXCR4 may be a potential therapeutic target for inflammation-induced anxiety. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Programmed death of neuronal cells plays a crucial role in acute and chronic neurodegeneration following TBI. The tumor suppressor protein p53, a transcription factor, has been recognized as an important regulator of apoptotic neuronal death. The p53 inactivator pifithrin-α (PFT-α) has been shown to be neuroprotective against stroke. A previous cellular study indicated that PFT-α oxygen analog (PFT-α (O)) is more stable and active than PFT-α. We aimed to investigate whether inhibition of p53 using PFT-α or PFT-α (O) would be a potential neuroprotective strategy for TBI. To evaluate whether these drugs protect against excitotoxicity in vitro, primary rat cortical cultures were challenged with glutamate (50 mM) in the presence or absence of various concentrations of the p53 inhibitors PFT-α or PFT-α (O). Cell viability was estimated by LDH assay. In vivo, adult Sprague Dawley rats were subjected to controlled cortical impact (CCI, with 4 m/s velocity, 2 mm deformation). Five hours after injury, PFT-α or PFT-α (O) (2 mg/kg, i.v.) was administered to animals. Sensory and motor functions were evaluated by behavioral tests at 24 h after TBI. The p53-positive neurons were identified by double staining with cell-specific markers. Levels of mRNA encoding for p53-regulated genes (BAX, PUMA, Bcl-2 and p21) were measured by reverse transcription followed by real time-PCR from TBI animals without or with PFT-α/PFT-α (O) treatment. We found that PFT-α(O) (10 μM) enhanced neuronal survival against glutamate-induced cytotoxicity in vitro more effectively than PFT-α (10 μM). In vivo PFT-α (O) treatment enhanced functional recovery and decreased contusion volume at 24 h post-injury. Neuroprotection by PFT-α (O) treatment also reduced p53-positive neurons in the cortical contusion region. In addition, p53-regulated PUMA mRNA levels at 8 h were significantly reduced by PFT-α (O) administration after TBI. PFT-α (O) treatment also decreased phospho-p53 positive neurons in the cortical contusion region. Our data suggest that PFT-α (O) provided a significant reduction of cortical cell death and protected neurons from glutamate-induced excitotoxicity in vitro, as well as improved neurological functional outcome and reduced brain injury in vivo via anti-apoptotic mechanisms. The inhibition of p53-induced apoptosis by PFT-α (O) provides a useful tool to evaluate reversible apoptotic mechanisms and may develop into a novel therapeutic strategy for TBI. [ABSTRACT FROM AUTHOR]

A proof of concept integrating binary p-n heterojunctions into a semiconductor hybrid photocatalyst is demonstrated by non-covalent doping of graphite-like carbon nitride (g-C3N4) with ultrathin GO and MoS2 nanosheets using a facile sonochemical method. In this unique ternary hybrid, the layered MoS2 and GO nanosheets with a large surface area enhance light absorption to generate more photoelectrons. On account of the coupling between MoS2 and GO with g-C3N4, the ternary hybrid possesses binary p-n heterojunctions at the g-C3N4/MoS2 and g-C3N4/GO interfaces. The space charge layers created by the p-n heterojunctions not only enhance photogeneration, but also promote charge separation and transfer of electron-hole pairs. In addition, the ultrathin MoS2 and GO with high mobility act as electron mediators to facilitate separation of photogenerated electron-hole pairs at each p-n heterojunction. As a result, the ternary hybrid photocatalyst exhibits improved photoelectrochemical and photocatalytic activity under visible light irradiation compared to other reference materials. The results provide new insights into the large-scale production of semiconductor photocatalysts. [ABSTRACT FROM AUTHOR]

In this work, a simple distribution function-based gas-kinetic scheme for simulation of viscous flows is presented. The work applies the finite volume method to discretize the governing differential equations, and inviscid and viscous fluxes at the cell interface are evaluated simultaneously by local reconstruction of solution for the continuous Boltzmann equation. Differently from the conventional gas-kinetic scheme [13-15], in the present work, the Maxwellian distribution function is simplified by a simple distribution function, and integrals in the infinity domain of phase space are reduced to integrals around a circle. As a consequence, the computational efficiency is greatly improved. Since the simple distribution function is defined on the circle, for simplicity, it is termed as circular function hereafter. The present work is the extension of our previous work [20], where the circular function-based gas-kinetic scheme is presented to simulate inviscid flows. Only the equilibrium distribution function is considered in [20]. To solve viscous flows, the non-equilibrium part of density distribution function has to be considered. One of major contributions in this work is to present a simple way to compute the non-equilibrium part of the distribution function. It can be calculated by the difference of equilibrium distribution functions at the cell interface and its surrounding point. As a result, the formulations for computing the conservative flow variables and fluxes at the cell interface can be given explicitly. The present solver can simulate both incompressible and compressible viscous flows. To validate the proposed new gas-kinetic scheme, several incompressible and compressible viscous flows are simulated. Numerical results showed that the circular function-based gas-kinetic scheme can provide accurate numerical results with the same computational cost as that needed by conventional Navier-Stokes solver. [ABSTRACT FROM AUTHOR]

• Domains need to be partitioned when constructing analogs for geophysical models. • Patches make the training of machine learning models more robust. • The use of patches makes in data assimilation can be implemented in parallel. • General autoencoders with an affine transformation in the latent space can be used. • Patched constructed analogs can approximate ensemble members within DA methods. Using generative models from the machine learning literature to create artificial ensemble members for use within data assimilation schemes has been introduced in Grooms (2021) [1] as constructed analog ensemble optimal interpolation (cAnEnOI). Specifically, we study general and variational autoencoders for the machine learning component of this method, and combine the ideas of constructed analogs and ensemble optimal interpolation in the data assimilation piece. To extend the scalability of cAnEnOI for use in data assimilation on complex dynamical models, we propose using patching schemes to divide the global spatial domain into digestible chunks. Using patches makes training the generative models possible and has the added benefit of being able to exploit parallelism during the generative step. Testing this new algorithm on a 1D toy model, we find that larger patch sizes make it harder to train an accurate generative model (i.e. a model whose reconstruction error is small), while conversely the data assimilation performance improves at larger patch sizes. There is thus a sweet spot where the patch size is large enough to enable good data assimilation performance, but not so large that it becomes difficult to train an accurate generative model. In our tests the new patched cAnEnOI method outperforms the original (unpatched) cAnEnOI, as well as the ensemble square root filter results from [1]. [ABSTRACT FROM AUTHOR]

Abstract: The existence of a mega-paleolake centered on Jilantai Salt Lake, Inner Mongolia, China, has long been suspected. In the present study, shorelines around Jilantai were identified from astronaut photographs, analyses of Landsat-7 ETM+ images, field surveys and differential global positioning system (DGPS) surveys. Here we characterize 1070–1080, 1060, 1050, 1044 and 1035m (a.s.l.) shorelines around Jilantai, which probably correspond to rapid climatic oscillations and tectonic movement and call for further study. Field surveys around Jilantai and in the Hetao Plain located widespread lacustrine deposits and shorelines that provide evidence for a mega-paleolake covering much of the Jilantai and Hetao basins. Based on preliminary Optically Stimulated Luminescence (OSL) dating, we speculate that a series of paleolakes probably occupied this region from Marine Isotope Stage 3 (MIS3) to the Holocene. More detailed investigation is needed for understanding the lake evolution, as well as the environmental impact of Quaternary climatic changes in this region. [Copyright &y& Elsevier]

Decomposition of soil organic carbon (SOC) is a critical component of the global carbon cycle, and accurate estimates of SOC decomposition are important for forest carbon modeling and ultimately for decision making relative to carbon sequestration and mitigation of global climate change. We determined the major pools of SOC in four sites representing major forest types in China: temperate forests at Changbai Mountain (CBM) and Qilian Mountain (QLM), and sub-tropical forests at Yujiang (YJ) and Liping (LP) counties. A 90-day laboratory incubation was conducted to measure CO2 evolution from forest soils from each site, and data from the incubation study were fitted to a three-pool first-order model that separated mineralizable soil organic carbon into active (Ca), slow (Cs) and resistant (Cr) carbon pools. Results indicate that: (1) the rate of SOC decomposition in the sub-tropical zone was faster than that in the temperature zone, (2) The Ca pool comprised ∼1–3% of SOC with an average mean residence time (MRT) of 219 days. The Cs pool comprised ∼25–65% with an average MRT of 78yr. The Cr pool accounted for ∼35–80% of SOC, (3) The YJ site in the sub-tropical zone had the greatest Ca pool and the lowest MRT, while the QLM in the temperature zone had the greatest MRT for both the Ca and Cs pools. The results suggest a higher capacity for long-term C sequestration as SOC in temperature forests than in sub-tropical forests. [Copyright &y& Elsevier]

Abstract: Local structure of Cu in a type-I Ba8Cu4Si42 clathrate has been investigated by synchrotron X-ray powder diffraction, Cu K-edge extended X-ray absorption fine spectroscopy, X-ray absorption near edge spectroscopy (XANES) and theoretical calculation. It is found that XANES spectra cannot be explained by the substitution of Cu atoms at Si16i, and Si24k positions. Our calculations show that the binding energies of the Si atom in Si16i, Si24k and Si6c positions are 9.000, 9.495 and 8.911eV, respectively. Both experimental and theoretical results support that Cu atoms in the type-I Ba8Cu4Si42 clathrate, as a doped element, prefer to occupy the least-binding Si, i.e., the Si6c sites. No structural change between 112 and 300K was observed and the (100)-faceted cubic crystal has negligible distortion/ordering according to transmission electron microscopy. [Copyright &y& Elsevier]

Presents information on a study which explored the impacts of water resources redistribution and pollution prevention actions between and within river basins simultaneously in South Taiwan. Predicted situation of water quality in the dry season; Geographical and hydrological features of the site; Water Quality Model QUAL2E descriptions, calibration and validation: Simulation analysis.

• Integrating Factor methods are the better exponential integrator for wave turbulence. • A discrete-asymptotic analysis relates difference equations to asymptotic behavior. • A new near-minimax rational approximation for the matrix exponential is proposed for use in IF methods. • Implicit-Explicit integrators fundamentally treat wave resonances incorrectly. Exponential and IMEX integrators are considered for wave turbulence problems, which are stiff systems that often require long-time simulations. Applying a multi-scale asymptotic analysis to the difference equations for a simple wave turbulence problem reveals that Exponential Runge-Kutta methods incorrectly model interactions between resonant waves unless they are specifically designed otherwise, and IMplicit-EXplicit (IMEX) integrators introduce dispersive and dissipative errors that severely degrade the accuracy of slow energy exchange between resonant waves. The same analysis shows Integrating Factor (IF) methods to be the most suitable. Numerical experiments performed on the resonant triad model and the Majda-McLaughlin-Tabak (MMT) model verify the discrete-asymptotic analysis. In the MMT problem, Exponential Time Differencing methods require a time step more than two orders of magnitude smaller than IF methods to achieve comparable accuracy, and IMEX methods require more than six orders of magnitude smaller time steps. A novel near-minimax rational approximation of the matrix exponential is proposed to be used for integrating factor methods, and is demonstrated to be as accurate as the IF method but without the need to compute a matrix exponential. [ABSTRACT FROM AUTHOR]

Abstract This paper studies the vibration characteristics of a drill string in gas drilling under gas-structure interactions, and affected by the combined effects of several parameters including the spinning motion, the weight on bit, the hydrodynamic force, the damping force of drilling fluid and the stabilizer. Based on the Hamilton's principle, the dynamic equations of the spinning drill string subjected to the weight on bit and gas-structure interaction are established and solved by using the Galerkin's method. The exact solutions of the i -th natural frequencies of the drill string with uniform section are derived considering the gas-structure interaction and the spinning motion, and the characteristic curves of the non-dimensional natural frequencies versus different parameters are obtained respectively. The results show that the spinning angular speed, the weight on bit, the flow velocity, the viscous damping force of drilling fluid, the ratio of the external diameter of drill pipe to that of the drill collar and different installation positions of the stabilizer have significant influences on the dynamic characteristics of the drill string. In addition, the effects of the gas drilling fluid and the mud drilling fluid on the system vibration characteristics are discussed and compared, which reveal that natural frequencies of the drill string in gas drilling are higher than that in mud drilling. [ABSTRACT FROM AUTHOR]

Understanding the source of phenotypic variability is a challenge in the biological sciences. Variation in phenotypes is the result of variation in the genetics and environment the organism experiences, but elucidating the relative contribution of these two parameters can pose problems, especially in the field of systematics. Systematists are challenged to classify biological diversity into groups that share common ancestry. Phenotypic variation can be useful to demonstrate common ancestry, but only when the primary contributor to the variation is under strong genetic control, and thus heritable. Cusick’s milkvetch ( Astragalus cusickii ) is a perennial forb endemic to the northwestern intermountain region of the United States. The species currently comprises four varieties based on subtle morphological dissimilarities, such as leaf size and density, and the size and shape of the seed pods. The taxonomic organization of the varieties of A. cusickii and related species of Astragalus were reexamined through phylogenetic analysis of low copy nuclear, nuclear-ribosomal, and chloroplast gene regions. Maximum parsimony, maximum likelihood, Bayesian inference, the genealogical sorting index, and an approximately unbiased test were used to determine appropriate species boundaries under the phylogenetic species concept. The results support reclassification of A. cusickii var. packardiae and A. cusickii var. sterilis as separate species. Additionally, evidence suggests a chloroplast capture event may have occurred in one population of A. cusickii var. packardiae . [ABSTRACT FROM AUTHOR]

Many factors (e.g. sex, stress) modulate wound healing and thereby alter the risk of developing bacterial infections or chronic, non-healing wounds. Previous research indicates that sex influences dermal wound healing; females heal quicker than males, likely due to differences in testosterone. Stressors (e.g., social isolation) can also impair wound healing. In combination, sex modulates the effects of stressors on other types of immune processes. However, the mechanisms underlying isolation stress-impaired healing, and how sex may modulate these mechanisms, remain unexplored. Here, we hypothesized that social isolation inhibits healing more in female than in male mice. Male and female SKH-1 mice were single- or group-housed (5/cage) for 3 weeks prior to wounding. Two 3.5mm dorsal skin wounds were then placed on each mouse and wound closure was assessed daily for 5 days. Wound tissue samples were collected 1, 3, or 5 days after wounding and used to quantify gene expression of factors associated with wound healing and wound bacterial load. Isolation delayed wound closure in both sexes, but was more pronounced in males. Isolation also reduced wound bacterial burden in both sexes, which persisted in males only and corresponded with decreased wound inflammatory gene expression (IL-1beta, monocyte chemoattractant protein-1). Isolation also decreased alpha-smooth muscle actin (involved in wound contraction) in males, but not females, which may have contributed to their lasting healing delays. [ABSTRACT FROM AUTHOR]

Introduction: Cold is one of several important pathogenic factors in conditions such as livedo reticularis with winter ulceration (LRWU) , cold urticaria . As yet however, the effects resulting from cold stimulation remain poorly understood. Methods: In the present study, using DNA microarray analysis, we investigated gene expression profiles in cultured human normal dermal microvascular endothelial cells (dHMVECs) exposed to different temperatures (10, 20 and 37°C). Quantitative real-time polymerase chain reaction (qPCR) was used to confirm gene expression results obtained from DNA microarray. ELISA assay was used to evaluate protein expression in culture medium of dHMVECs, mice and patients’ sera. Results: By DNA microarray analysis, differential transcriptional expressions of 137 genes were identified compared to 37°C. 21 genes were both regulated at 10 degrees C and 20°C, 19.05% (4 in 21) of which encode proteins which are related to the immune response (cytokines, chemokines, their receptors, cytokine/chemokines-related genes). Under cold stimulation, the production of the neutrophil chemokine interleukin (IL)-8 and CXC chemokine ligand (CXCL)1 was found remarkably up-regulated by both DNA microarray and qPCR analyses. IL-8 and CXCL1 mRNA were present at detectable levels even in the nontreated control dHMVECs and significantly up-regulated (Ratio 10 centigrade C/37 degrees C: IL8, 1.46±0.13-fold, p =0.0122; CXCL1, 2.40±0.35-fold, p =0.0100) within 2h after cold stimulation and remained elevated for up to 12-h. Up-regulated protein expressions of IL8 and CXCL1 were found in culture medium of dHMVECs and mouse serum after cold stimulation, and also in sera from patients, who suffer from LRWU and cold urticaria. Neutrophil migration in the presence of conditional medium from cold-stimulated dHMVECs is currently under investigation. Conclusion: Our results showed that cold induced expression of different genes. This is the first time to show that cold can affect the expression profile of chemokines in dHMVECs, which may contribute to the accumulation of neutrophils and inflammation in dermal vascular. They might be candidate biomarkers of diseases resulting from exposure to cold. [Copyright &y& Elsevier]

Recent data have demonstrated variability in the degree to which voluntary exercise prevents the hyperphagia and obesity in rodent obesity models. OLETF rats lacking CCK1 receptors and melanocortin-4 receptor knockout mice normalize food intake and body weight when given access to a running wheel, whereas exercise seems to have only minimal effects on the obesity of Zucker fatty (fa/fa) or Koletsky (fak/fak, SHROB) rats both congenitally lacking leptin receptors. To further characterize responses to voluntary exercise in the absence of leptin signaling, we determined food intake, body weight and hypothalamic gene expression in SHROB rats in response to running wheel access. We found that sedentary SHROB rats had increased food intake and body weight as compared to lean rats. SHROB rats did use the running wheel but to a less degree than that demonstrated in other models and this degree of activity did not significantly affect food intake or body weight. When we pair fed SHROB rats to the amounts consumed by lean controls, running activity was increased and overall resulted in body weight loss. This combination also resulted in a decrease in blood glucose levels, but did not significantly alter fat mass. Real-time RT PCR determination revealed that the combination of pair feeding and voluntary exercise resulted in further increased NPY and decreased POMC gene expression in the arcuate nucleus compared to sedentary SHROB rats. Together, these data demonstrated that voluntary exercise is not sufficient for preventing the obesity of SHROB rats. (Supported by DK074269). [Copyright &y& Elsevier]

Abstract: Time series often contain unknown trend functions and unobservable error terms. As is known, Yule–Walker estimators are asymptotically efficient for autoregressive time series. The focus of this article is the Yule–Walker estimators for time series with trends. A nonparametric detrending procedure is proposed. It is concluded that the asymptotic properties of the Yule–Walker estimators of autoregressive coefficients are not altered by the detrending procedure. The results of the simulation studies and real data application corroborate the asymptotic theory. [Copyright &y& Elsevier]

The integrated terrestrial ecosystem C-budget model (InTEC) developed by Chen and co-workers has been used successfully to predict carbon dynamics of forests in Canada. It was tested here for forest soil organic carbon (SOC) density of China''s northern temperate zone and southern subtropical zone. The results show that the simulated SOC density is highly correlated and in broad agreement with observations in Liping and in Changbaishan, representing the southern subtropical zone and the northern temperate zone in China, respectively. SOC density ranged from 2.2 to 11.2kg/m2 in Liping and from 3.4 to 14.8kg/m2 in Changbaishan. The correlation coefficients (r 2) are 0.63 (N=16) and 0.76 (N=14) between the simulated and measured data in Liping and Changbaishan, respectively. The SOC densities under different vegetation types in Liping decrease in the order of mixed forest, broadleaf forest, Chinese fir, couch grass, and Chinese redpine, and in Changbaishan in the order of mixed forest, silver fir, larch forest, and birch forest. [Copyright &y& Elsevier]

Our previous research revealed that rifampicin could protect PC12 (pheochromocytoma 12) cells from rotenone-induced cytotoxicity by reversing the aggregation of α-synuclein. Furthermore, increasing evidence indicated that the misfolded α-synuclein with SUMOylation, an important protein posttranslational modification, was easier to solubilize and was less toxic. Here, we investigated whether rifampicin could stabilize α-synuclein and prevent rotenone-induced PC12 cells from undergoing apoptosis by enhancing SUMOylation of α-synuclein. The expression of SUMO1 and SUMO2/3, the two main proteins responsible for the SUMOylation modification in PC12 cells, were detected by western blotting. Co-immunoprecipitation was performed to compare qualitatively the SUMOylation modification of α-synuclein. The cell viability and apoptosis rate were measured by a CCK-8 assay kit and flow cytometry, respectively. We targeted Ubc9 as a key enzyme in the SUMOylation modification pathway and knocked down the UBC9 gene using a short interfering RNA. Treatment with 150 μmol/L rifampicin, increased the expressions of SUMO1 and SUMO2/3 in cells by 1.5 times compared with the control group; meanwhile, the cell viability of rotenone-induced cells increased from 20 to 80% ( P < 0.05). In addition, the increased SUMOylation activity in the cells stimulated by rifampicin was observed 18 h earlier compared with cells treated by rotenone alone. SUMOylation of α-synuclein was more significant in rifampicin-treated cells and Ubc9 upregulated cells. However, the same phenomenon and the protective effect of rifampicin were reversed after UBC9 knockout. In conclusion, rifampicin might reduce the cytotoxicity of rotenone-induced PC12 cells by promoting SUMOylation of α-synuclein. [ABSTRACT FROM AUTHOR]

Based on the density matrix approach, the effects of ternary mixed crystal and size on intersubband optical absorption coefficients in In x Ga 1− x N/GaN core–shell nanowires (CSNWs) are investigated. The results show that the optical absorption can be modulated by In component x and the size of CSNWs, since the variation of electron states in these systems. It is found that photonic frequencies of resonant absorption and the absorption coefficient increase obviously when x increases or the radius of InGaN core reduces, while the half-width of the coefficient decreases as its peak becomes higher and sharper. A saturation phenomenon of optical absorption is also found when the incident light intensity exceeds a certain value. The theoretical results are expected to be helpful to develop CSNW optic devices. [ABSTRACT FROM AUTHOR]

Direct current sputtering was used to growth Al-doped ZnO (AZO) thin films at various substrate temperatures. Structural and optical properties of AZO thin films were investigated by X-ray diffraction (XRD), energy dispersive X-ray (EDX) and Ultraviolet–Visible–Near IR spectroscopy. According to the XRD patterns, all films showed an hexagonal wurtzite structure with a preferred orientation along c -axis. EDX showed that all films are doped with 1% wt of Al. The transmittance and reflectance changed with the substrate temperature T s . AZO has a high transmittance which is a crucial parameter for optical materials and applications. Thus, it is important to determine optical constants of the films. In this order, optical parameters such as the optical band gap, absorption coefficient, extinction coefficient, refractive index, dispersion parameter, dielectric constants and optical conductivity were studied in order to investigate the effects of T s on the optical properties of AZO thin films. The dispersion energy, single-oscillator strength and the long wavelength refractive index of the AZO thin films were found to be affected by substrate temperature T s . [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) can form DNA-binding compounds that show genotoxicity and carcinogenicity. Pyrene, as a PAH, was covalently linked to carrier protein bovine serum albumin and ovalbumin. A monoclonal antibody (McAb) was produced that showed high cross-reactivity values with chrysene (169.73%), benzo[a]pyrene (693.34%), benzo[a]anthracene (16.36%), and indeno[1,2,3-cd]pyrene (40.96%) and showed no significant cross-reactivity values with other homologues (<0.1%). A competitive enzyme-linked immunosorbent assay (ELISA) was developed for detection of pyrene and some homologues in water samples. The detection limit of the assay was 65.08 pg ml −1 . The average recoveries of PAHs from tap water, lake water, and mineral water were 99.13, 99.74, and 99.19%, respectively, indicating that matrices of water samples do not interfere with the assay. The results demonstrated that the developed ELISA seems to be a potential method for monitoring of pyrene and some homologous PAHs in water samples. [ABSTRACT FROM AUTHOR]

Introduction: The New Zealand Black (NZB)×New Zealand White (NZW) F1 hybrid female mice (NZB/WF1) develop a disease closely resembling human systemic lupus erythematosus (SLE), characterized by the production of antinuclear antibodies, severe glomerulonephritis and early mortality. Recently, innate immune responses have been reported to play an important role in the development of autoimmune disease. In this study we investigated the role of Myd88 protein (an important regulator of innate immune signaling pathways) in the pathogenesis of lupus-like disease in Myd88 knockout NZB/W F1 mice. Methods: The Myd88-deficient mice were backcrossed separately in the NZB and NZW backgroud. Heterozygous NZB as well as NZW of F10 backcross generation were intercrossed to achieve Myd88 -/- NZB/W F1 mice (KO) and Myd88 +/+ NZB/W F1 mice (WT). WT and Myd88 KO mice were compared for serum concentrations of anti-dsDNAantibody, biochemical markers of active disease (BUN, Cr, Alb, TP, T-CHO, protein urea), histological analysis of kidney pathology and mortality. Results: Compared with WT mice, Myd88 KO mice featured significantly reduced serum concentrations of anti-dsDNAantibody, reduced levels of biochemical markers of active disease, reduced kidney pathology and reduced mortality. Conclusion: Our result indicates that innate immunity participates in the pathogenesis of lupus prone mice and Myd88 is its important regulator. [ABSTRACT FROM AUTHOR]

Abstract: This study evaluated Sporidiobolus pararoseus (Sp) strain YCXT3 as biocontrol agent of Botrytis cinerea (Bc), the causal agent of strawberry gray mold disease. Efficacy of live yeast cells and volatile organic compounds (VOCs) of Sp in suppression of Bc on strawberry fruits was determined. Results showed that in dual cultures of Sp and Bc on potato dextrose agar at 20°C, Sp did not inhibit mycelial growth of Bc. However, inoculation of the yeast cell suspensions of Sp (1×105 or 1×106 yeast cells ml−1) on strawberry fruits resulted in reducing the disease incidence from 96–100% in the control treatment to 39–50% in the Sp treatment and the disease severity index from 5.1–7.0 in the control treatment to 1.1–1.9 in the Sp treatment. We found that the VOCs from the Sp cultures on yeast extract peptone dextrose agar were highly effective in inhibiting both the conidial germination and the mycelial growth of Bc. A total of 39 VOCs, including 2-ethyl-1-hexanol, were identified in cultures of Sp using GC–MS. Authentic 2-ethyl-1-hexanol was found to have strong anti-fungal activity against Bc with the IC50 values of 1.5 and 5.4μll−1 for conidial germination and mycelial growth, respectively. The VOCs from the Sp cultures were effective in suppression of gray mold disease under the air-tight conditions. This study suggests that the strain YCXT3 of Sp is a promising agent for control of Bc and production of VOCs is a valid biocontrol mechanism for this yeast strain. [Copyright &y& Elsevier]

It is well accepted that stress can negatively affect healing. Restraint-stressed mice exhibit delayed wound closure and have greater bacterial loads than controls, suggesting that bacterial clearance is impaired in this model. Interestingly, wound healing in isolated mice is delayed to a similar magnitude, yet these wounds have low bacterial loads. This finding challenges the notion that stress-impaired healing requires impaired bacterial clearance; here we explore its role (and necessity). Bacteria samples were collected from the skin of group-housed mice and cultured. Three housing conditions were established: group-housed, isolated 3 weeks before wounding, and isolated at wounding. Mice received two 3.5mm dorsal punch biopsies. 25μL of vehicle or bacteria solution was placed topically on each wound. Daily photographs monitored wound closure. Regardless of bacterial burden, group-housed mice exhibited faster wound closure than isolated mice. Artificially increasing bacterial load to that of control animals resulted in higher bacterial counts in isolates. The addition of bacteria did not affect healing rates in isolates, whereas it accelerated healing in group-housed controls. Surprisingly, similar healing delays were seen in mice that were isolated immediately or at 3 weeks prior to wounding. These data indicate that isolation-stress immediately alters tissue repair. In this model, bacterial burden did not appear to affect wound closure rates. These results indicate that social stressors negatively impact tissue repair comparably to other stressors, but through disparate mechanisms. [ABSTRACT FROM AUTHOR]

Introduction: Anti-viral immune responses involve the robust production of type-I interferon (IFN-α/β) in plasmacytoid dendritic cells (pDCs). This occurs through the virus-activated MyD88-independent pathway, or the TLR7, 9/MyD88 pathways, and is completely dependent on the transcription factor IRF7 . How type-I IFN is negatively regulated with respect to IRF7 remains unknown.Here we report that peroxisome proliferator-activated receptor gamma (PPAR-γ) is a negative-feedback regulator of IRF7-dependent TLR signaling for type-I IFN production. Methods: WT and PPAR-γ (+/−) mice were used for in vitro stimulation of pDCs with TLR agonists, or i.v delivery of TLR agonists. Levels of type-I IFN in culture supernatants were assessed by ELISA. Interactions between IRF7 and PPAR-γ were studied by FLAG-IRF7 immunoprecipitation and Western blot analysis for PPAR-γ. Pristane (0.5 ml) was injected into WT and PPAR-γ (+/−) C57BL/6 to develop lupus-like disease, or control PBS. Interferon responses in mice were assessed by RT-PCR and ELISAs for autoantibodies. Results: Through TLR7, 9/MyD88 signaling in pDCs, type-I IFN induces the expression of PPAR-γ, which binds to the DNA-binding domain of IRF7, inhibiting IRF7 activation of type-I IFN genes. A critical role in vivo was confirmed in PPAR-γ (+/−) mice, which displayed enhanced TLR9-type-I IFN induction, compared to WT mice. Using the pristane-induced lupus model (TLR7/MyD88-type-IFN-dependent ), disease in PPAR-γ (+/−) mice correlated with enhanced type-I IFN production/signaling, type-I IFN-dependent anti-nuclear antibody production and poor survival, compared to in WT mice. Pioglitazone (a PPAR-γ agonist) treatment inhibits murine lupus through a potent inhibitory effect on type-I IFN signaling. Conclusion: Thus, the role of PPAR-γ in murine lupus, as a key regulator of type-I IFN production, provides a compelling argument for the therapeutic application of PPAR-γ agonists in human lupus, which is considered to be IFN-α-driven . [Copyright &y& Elsevier]

Introduction: Amyotrophic Lateral Sclerosis (ALS) is an adult-onset, progressive, motor neuron degenerative disease. Recent evidence indicates that inflammation is associated with many neurodegenerative diseases including ALS. Previously, abnormal levels of inflammatory cytokines including IL-1, IL-6 and TNF-alpha were described in ALS patients and/or mouse ALS models. In addition, one study showed that blocking IL-1 beta could slow down progression of ALS-like symptoms in mice. In this study, we examined a role for IL-6 in ALS, using an animal model for ALS. Methods: Mice with mutant SOD1 (G93A), a model for ALS, were crossed with IL-6(−/−) mice to generate SOD1 (G93A)/IL-6(−/−) mice. SOD1 (G93A)/IL-6(−/−) mice (n =18) were compared with SOD1 (G93A) mice (n =29), WT mice (n =15) and IL-6(−/−) mice (n =8) from 12weeks of age, with respect to neurological disease severity score, body weight and the survival. Results: The clinical scores of SOD1 (G93A)/IL-6(−/−) mice was comparable to that of SOD1 G93A mice at pre-symptomatic, early symptomatic and end stage of disease, suggesting that the motor functions of mutant mice deteriorated similarly with or without IL-6. In addition, SOD1 (G93A)/IL-6(−/−) mice and SOD1 G93A and exhibit similar body weight loss after disease onset. The lifespan of SOD1 (G93A)/IL-6(−/−) mice was also similar to that of SOD1(G93A) mice. WT mice or IL-6(−/−) mice showed no disease symptoms. Conclusion: These results suggest that IL-6 does not directly contribute to motor neuron degeneration caused by SOD1 mutations. [ABSTRACT FROM AUTHOR]