63 research outputs found

    Simvastatin Enhances Immune Responses to Aβ Vaccination and Attenuates Vaccination-Induced Behavioral Alterations

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    Statins are widely used to lower cholesterol levels by inhibiting cholesterol biosynthesis. Some evidence has indicated that statins might have therapeutic and preventive benefits for Alzheimer\u27s disease (AD). We and others also have shown the beneficial effect of statin treatment in reversing learning and memory deficits in animal models of AD. However, data from clinical trials are inconclusive. We previously documented that the adenovirus vector encoding 11 tandem repeats of Aβ1-6 fused to the receptor-binding domain (Ia) of Pseudomonas exotoxin A, AdPEDI-(Aβ1-6)(11), is effective in inducing an immune response against amyloid-β protein (Aβ) and reducing brain Aβ load in Alzheimer\u27s mouse models. In the present study, we examined whether the administration of simvastatin can modulate immune and behavioral responses of C57BL/6 mice to vaccination. Simvastatin was given to the animals as a diet admixture for four weeks, followed by nasal vaccination with AdPEDI-(Aβ1-6)(11) once per week for four weeks. The cholesterol-lowering action of simvastatin was monitored by measuring the cholesterol levels in plasma. Simvastatin significantly increased the number of the mice responding to vaccination compared with the mice receiving only AdPEDI-(Aβ1-6)(11). Immunoglobulin isotyping revealed that the vaccination predominantly induced Th2 immune responses. Simvastatin treatment prevented Aβ-induced production of IFN-γ in splenocytes. The adenovirus vaccination altered mouse behavior in T- and elevated plus-maze tests and simvastatin counteracted such behavioral changes. Our results indicate that simvastatin clearly enhances the immune responses of C57BL/6 mice to the nasal vaccination with AdPEDI-(Aβ1-6)(11). Simvastatin may be effective in preventing behavioral changes associated with vaccination

    Simultaneous removal of malachite green and hexavalent chromium by Cunninghamella elegans biofilm in a semi-continuous system

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    The present study was conducted to evaluate the potential of the fungus Cunninghamella elegans for simultaneous decolourisation of a triphenylmethane dye malachite green (MG) and hexavalent chromium [Cr(VI)] in the same media. This fungus can degrade MG through its reduction into leucomalachite green and then demethylation followed by oxidative cleavage. Along with MG degradation, C. elegans biofilm could effectively and repeatedly remove Cr(VI) from the liquid cultures even in the presence of high concentrations (40 g L−1) of NaCl and various other metal ions. C. elegans biofilm was also found to adsorb different dyes (reactive black-5, acid orange 7, direct red 81 and brilliant blue G) concurrently with Cr(VI). Based on its potential for simultaneous removal of dyes and Cr(VI) as well as reusability, C. elegans biofilm is envisaged as an efficient bioresource to devise strategies for treatment of wastewaters loaded with multiple pollutants.Environmental Protection AgencyIrish Research Counci

    Classification and biological identity of complex nano shapes

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    Everywhere in our surroundings we increasingly come in contact with nanostructures that have distinctive complex shape features on a scale comparable to the particle itself. Such shape ensembles can be made by modern nano-synthetic methods and many industrial processes. With the ever growing universe of nanoscale shapes, names such as “nanoflowers” and “nanostars” no longer precisely describe or characterise the distinct nature of the particles. Here we capture and digitise particle shape information on the relevant size scale and create a condensed representation in which the essential shape features can be captured, recognized and correlated. We find the natural emergence of intrinsic shape groups as well-defined ensemble distributions and show how these may be analyzed and interpreted to reveal novel aspects of our nanoscale shape environment. We show how these ideas may be applied to the interaction between the nanoscale-shape and the living universe and provide a conceptual framework for the study of nanoscale shape biological recognition and identity

    Chemical Components from the Light Petroleum Soluble Fraction of Uvaria cordata (Dunal) Alston

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    Chromatographic separation of the light petroleum extract from the stem bark of Uvaria cordata (Dunal) Alston led to the isolation of the triterpenoids glutinol and taraxerol in addition to the cyclohexene derivatives, pipoxide and its chlorohydrin. A small amount of benzyl benzoate was also isolated

    Differential Response of Soil Respiration and Total Belowground Carbon Allocation to Simulated Nitrogen and Phosphorus Deposition in Moso Bamboo Forests

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    Elevated nitrogen (N) and phosphorus (P) depositions have greatly affected belowground carbon processes in forest ecosystems. However, open questions still remained on the effects of N and P depositions on belowground carbon processes, including soil respiration (RS), its source components—autotrophic respiration (RA) and heterotrophic respiration (RH), and total belowground carbon allocation (TBCA) in Moso bamboo forests—one of the most important forest types with wide distributions in subtropical China. To fill this knowledge gap, a two-year N, P, and NP experiment was conducted in Moso bamboo forests. Results showed that RS, RA, and RH had a strong seasonal variability and were exponentially correlated with soil temperature. N and P depositions did not change RS and RA. However, P deposition increased RH due to the stimulation of microbial activities, indicating a significant soil carbon loss under P deposition. N and P depositions did not affect TBCA. However, NP deposition significantly increased root carbon-use efficiency. Net ecosystem production (NEP) varied from 198 ± 104 to 529 ± 225 g C m−2 year−1, indicating that Moso bamboo is an important carbon sink. P deposition marginally decreased NEP, while N and NP depositions did not affect NEP, which indicates that N deposition alleviated the suppression of P deposition on NEP. These findings highlight the inconsistent responses of RA, RH, and NEP to N, P, and NP depositions, which should be differently considered to increase the accuracy of predicting belowground carbon dynamics

    Clay Minerals Change the Toxic Effect of Cadmium on the Activities of Leucine Aminopeptidase

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    Soil leucine aminopeptidase (LAP) is a hydrolytic enzyme involved in the acquisition of nitrogen by microorganisms. In contaminated soils, LAP activity is affected not only by the type and concentration of heavy metals but also by the form of enzyme. Here, we investigated the degree and mechanism of cadmium (Cd) inhibition of soil LAP and purified LAP. We also examined the effect of montmorillonite and kaolinite on LAP and LAP contaminated with Cd. The results showed that Cd inhibition of LAP activity increased with increasing Cd concentration and that Cd exerted noncompetitive inhibition of LAP. The addition of clay minerals decreases LAP activity and the maximum reaction rate (Vmax), regardless of the presence of Cd. Montmorillonite decreases the affinity of LAP to the substrate (Km), while kaolinite increases the affinity of LAP to the substrate. The clay mineral-immobilized LAP showed an increase in resistance to Cd contamination compared with the free LAP. The results obtained in this study may aid in understanding the toxic effects of heavy metals on soil enzymes

    Experimental Study on the Characteristics of Fire Smoke Movement in Ultra Thin and Tall Atriums by Hot Smoke Test

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    The characteristics of smoke natural filling in ultra thin and tall atriums were investigated by hot smoke test method. For the fire located on the atrium ground, the smoke touched the side wall first and then extended both upwards and downwards. The smoke plume rising velocity variation can be divided into four stages, different from the normal law in large spaces. In the very early stage of natural filling, the smoke concentration near the height of wall touching point was highest and maintained at a high level in the whole process. The linear trend of temperature increasing in plume center above the height of touching point was broken, far less than the theoretical predictions, which verified the enhancement effect of boundary heat exchange caused by plume restriction. The variation tendencies of smoke density and temperature were similar during the hot smoke test,and there existed a good linear relation between these two parameters. The height-width ratio was calculated as 3.2 averagely by the test results when smoke plume would likely touch atrium walls, and it was very close to the theoretically derived value. This ratio can be used as the definition condition for ultra thin and tall atriums

    Experimental Study on the Characteristics of Fire Smoke Movement in Ultra Thin and Tall Atriums by Hot Smoke Test

    No full text
    The characteristics of smoke natural filling in ultra thin and tall atriums were investigated by hot smoke test method. For the fire located on the atrium ground, the smoke touched the side wall first and then extended both upwards and downwards. The smoke plume rising velocity variation can be divided into four stages, different from the normal law in large spaces. In the very early stage of natural filling, the smoke concentration near the height of wall touching point was highest and maintained at a high level in the whole process. The linear trend of temperature increasing in plume center above the height of touching point was broken, far less than the theoretical predictions, which verified the enhancement effect of boundary heat exchange caused by plume restriction. The variation tendencies of smoke density and temperature were similar during the hot smoke test,and there existed a good linear relation between these two parameters. The height-width ratio was calculated as 3.2 averagely by the test results when smoke plume would likely touch atrium walls, and it was very close to the theoretically derived value. This ratio can be used as the definition condition for ultra thin and tall atriums

    Vibration Test and Control of Factory a Building under Excitation of Multiple Vibrating Screens

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    In order to reduce the excessive vibration responses of a reinforced concrete frame structure induced by several vibrating screens working simultaneously, field vibration monitoring and some vibration reduction measures are carried out. The results of field vibration monitoring show that the maximum vertical vibration of the structure exceeds 106% of the limitation of building vibration. The results of the structural response analysis show that the excessive structural vibration is attributed to the resonance, as the frequency of the vibrating screens coincides with vertical natural frequency of the floors of the factory structure. Based on this fact, three vibration control measures, including damping, active vibration isolation of vibrating screens and structural vibration absorption, are proposed to mitigate the excessive vibration. In order to analyze the vibration control performance of the proposed schemes, the finite element dynamic model of the factory building structure is established, and the model is verified by the results of vibration and mode tests. Then, the damping system, vibration isolation system and vibration absorption system are set up in the models, and the vibration control performance of the three schemes are investigated. The results show that the measures, including vibration isolation and absorption, can reduce the vibration by more than 80%. Combined with the demand for a short construction period, the active vibration isolation of vibrating screens is finally selected. After the implementation of the scheme, the field monitoring data show that the structural vibration response is consistent with the finite element result and obviously weakened to meet the limitation. This study can provide a reference for the vibration control design for similar screening factory buildings
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