973 resultados para Biochemical effects of ethanol


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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)

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Plant extracts represent a great source of molecules, with insecticidal activity, which are used for pest control in several crop production systems. This work aimed to evaluate the toxicity of an aqueous extract of leaves of castor bean against larvae of Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) in search for different classes of molecules with insecticidal activities by using in vitro assays. The effects of the castor bean leaf extract on the food utilization, development, and survival of S. frugiperda larvae was evaluated by feeding the larvae an artificial diet supplemented with different concentrations of the extract (0%, 1%, 2.5%, 5%, and 10% w/v). The effects observed were dose-dependent, and the highest concentration evaluated (10% w/v) was the one the most affected food utilization by altering the nutritional indices, as well as larval weight gain, development time, and survivorship. In vitro assays to detect saponins, lectins, and trypsin inhibitors in the castor bean leaf extract were performed, but only trypsin inhibitors were detected. No preference for the diet source was detected in S. frugiperda by feeding the larvae in choice experiments with diets containing different concentrations of the castor bean extract tested. The data obtained indicate the existence of a potential molecule in the tested extract of castor bean to be used as an alternative insecticide to be integrated in the management of S. frugiperda.

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Rice bran oil was obtained from rice bran by solvent extraction using ethanol. The influence of process variables, solvent hydration (0-24% of water, on mass basis), temperature (60-90 degrees C), solvent-to-rice bran mass ratio (2.5:1 to 4.5:1) and stirrer speed (100-250 rpm) were analysed using the response surface methodology. The extraction yield was highly affected by the solvent water content, and it varied from 8.56 to 20.05 g of oil/100 g of fresh rice bran (or 42.7-99.9% of the total oil available) depending on the experimental conditions. It was observed that oryzanol and tocols behave in different ways during the extraction process. A larger amount of tocols is extracted from the solid matrix in relation to gamma-oryzanol. It was possible to obtain values from 123 to 271 mg of tocols/kg of fresh rice bran and 1527 to 4164 mg of oryzanol/kg of fresh rice bran, indicating that it is feasible to obtain enriched oil when this renewable solvent is used. No differences in the chemical composition of the extracted oils were observed when compared to the data cited in the literature. (C) 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

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EFFECTS OF ADDING LANTHANUM TO Ni/ZrO2 CATALYSTS ON ETHANOL STEAM REFORMING. The catalytic performance of Ni/ZrO2 catalysts loaded with different lanthanum content for steam reforming of ethanol was investigated. Catalysts were characterized by BET surface area, X-ray diffraction, UV-vis spectroscopy, temperature programmed reduction, and X-ray absorption fine structure techniques. Results showed that lanthanum addition led to an increase in the degree of reduction of both NiO and nickel surface species interacting; with the support, due to the higher dispersion effect. The best catalytic performance at 450 degrees C was found for the Ni/2LZ catalyst, which exhibited an effluent gaseous mixture with the highest H-2 yield.

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In Brazil, the species Tityus serrulatus is responsible for the most severe cases of scorpion envenomation. There is currently a need for new scorpion anti-venoms that are more effective and less harmful. This study attempted to produce human monoclonal antibodies capable of inhibiting the activity of T. serrulatus venom (TsV), using the Griffin.1 library of human single-chain fragment-variable (scFv) phage antibodies. Four rounds of phage antibody selection were performed, and the round with the highest phage antibody titer was chosen for the production of monoclonal phage antibodies and for further analysis. The scFv 2A, designated serrumab, was selected for the production and purification of soluble antibody fragments. In a murine peritoneal macrophage cell line (J774.1), in vitro assays of the cytokines interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, and IL-10 were performed. In male BALB/c mice, in vivo assays of plasma urea, creatinine, aspartate transaminase, and glucose were performed, as well as of neutrophil recruitment and leukocyte counts. It was found that serrumab inhibited the TsV-induced increases in the production of IL-6, TNF alpha, and IL-10 in J774.1 cells. The in vivo inhibition assay showed that serrumab also prevented TsV-induced increases in the plasma levels of urea, creatinine, aspartate transaminase, and glucose, as well as preventing the TsV-induced increase in neutrophil recruitment. The results indicate that the human monoclonal antibody serrumab is a candidate for inclusion in a mixture of specific antibodies to the various toxins present in TsV. Therefore, serrumab shows promise for use in the production of new anti-venom.

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Wine grape must deal with serious problems due to the unfavorable climatic conditions resulted from global warming. High temperatures result in oxidative damages to grape vines. The excessive elevated temperatures are critical for grapevine productivity and survival and contribute to degradation of grape and wine quality and yield. Elevated temperature can negatively affect anthocyanin accumulation in red grape. Particularly, cv. Sangiovese was identified to be very sensitive to such condition. The quantitative real-time PCR analysis showed that flavonoid biosynthetic genes were slightly repressed by high temperature. Also, the heat stress repressed the expression of the transcription factor VvMYBA1 that activates the expression of UFGT. Moreover, high temperatures had repressing effects on the activity of the flavonoids biosynthetic enzymes PAL and UFGT.Anthocyanin accumulation in berry skin is due to the balance between its synthesis and oxidation. In grape cv. Sangiovese, the gene transcription and activity of peroxidases enzyme was elevated by heat stress as a defensive mechanism of ROS-scavenging. Among many isoforms of peroxidases genes, one gene (POD 1) was induced in Sangiovese under thermal stress condition. This gene was isolated and evaluated via the technique of genes transformation from grape to Petunia. Reduction in anthocyanins concentration and higher enzymatic activity of peroxidase was observed in POD 1 transformed Petunia after heat shock compared to untrasformed control. Moreover, in wine producing regions, it is inevitable for the grape growers to adopt some adaptive strategies to alleviate grape damages to abiotic stresses. Therefore, in this thesis, the technique of post veraison trimming was done to improve the coupling of phenolic and sugar ripening in Vitis vinifera L. cultivar Sangiovese. Trimming after veraison showed to be executable to slow down the rate of sugar accumulation in grape (to decrease the alcohol potential in wines) without evolution of the main berry flavonoids compounds.

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In this study, some important aspects of the relationship between honey bees (Apis mellifera L.) and pesticides have been investigated. In the first part of the research, the effects of the exposure of honey bees to neonicotinoids and fipronil contaminated dusts were analyzed. In fact, considerable amounts of these pesticides, employed for maize seed dressing treatments, may be dispersed during the sowing operations, thus representing a way of intoxication for honey bees. In particular, a specific way of exposure to this pesticides formulation, the indirect contact, was taken into account. To this aim, we conducted different experimentations, in laboratory, in semi-field and in open field conditions in order to assess the effects on mortality, foraging behaviour, colony development and capacity of orientation. The real dispersal of contaminated dusts was previously assessed in specific filed trials. In the second part, the impact of various pesticides (chemical and biological) on honey bee biochemical-physiological changes, was evaluated. Different ways and durations of exposure to the tested products were also employed. Three experimentations were performed, combining Bt spores and deltamethrin, Bt spores and fipronil, difenoconazole and deltamethrin. Several important enzymes (GST, ALP, SOD, CAT, G6PDH, GAPDH) were selected in order to test the pesticides induced variations in their activity. In particular, these enzymes are involved in different pathways of detoxification, oxidative stress defence and energetic metabolism. The results showed a significant effect on mortality of neonicotinoids and fipronil contaminated dusts, both in laboratory and in semi-field trials. However, no effects were evidenced in honey bees orientation capacity. The analysis of different biochemical indicators highlighted some interesting physiological variations that can be linked to the pesticide exposure. We therefore stress the attention on the possibility of using such a methodology as a novel toxicity endpoint in environmental risk assessment.

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Since the advent of automobiles, alcohol has been considered a possible engine fuel1,2. With the recent increased concern about the high price of crude oil due to fluctuating supply and demand and environmental issues, interest in alcohol based fuels has increased2,3. However, using pure alcohols or blends with conventional fuels in high percentages requires changes to the engine and fuel system design2. This leads to the need for a simple and accurate conventional fuels-alcohol blends combustion models that can be used in developing parametric burn rate and knock combustion models for designing more efficient Spark Ignited (SI) engines. To contribute to this understanding, numerical simulations were performed to obtain detailed characteristics of Gasoline-Ethanol blends with respect to Laminar Flame Speed (LFS), autoignition and Flame-Wall interactions. The one-dimensional premixed flame code CHEMKIN was applied to simulate the burning velocity and autoignition characteristics using the freely propagating model and closed homogeneous reactor model respectively. Computational Fluid Dynamics (CFD) was used to obtain detailed flow, temperature, and species fields for Flame-wall interactions. A semi-detailed validated chemical kinetic model for a gasoline surrogate fuel developed by Andrae and Head4 was used for the study of LFS and Autoignition. For the quenching study, a skeletal chemical kinetic mechanism of gasoline surrogate, having 50 species and 174 reactions was used. The surrogate fuel was defined as a mixture of pure n-heptane, isooctane, and toluene. For LFS study, the ethanol volume fraction was varied from 0 to 85%, initial pressure from 4 to 8 bar, initial temperature from 300 to 900K, and dilution from 0 to 32%. Whereas for Autoignition study, the ethanol volume fraction was varied between 0 to 85%, initial pressure was varied between 20 to 60 bar, initial temperature was varied between 800 to 1200K, and the dilution was varied between 0 to 32% at equivalence ratios of 0.5, 1.0 and 1.5 to represent the in-cylinder conditions of a SI engine. For quenching study three Ethanol blends, namely E0, E25 and E85 are described in detail at an initial pressure of 8 atm and 17 atm. Initial wall temperature was taken to be 400 K. Quenching thicknesses and heat fluxes to the wall were computed. The laminar flame speed was found to increase with ethanol concentration and temperature but decrease with pressure and dilution. The autoignition time was found to increase with ethanol concentration at lower temperatures but was found to decrease marginally at higher temperatures. The autoignition time was also found to decrease with pressure and equivalence ratio but increase with dilution. The average quenching thickness was found to decrease with an increase in Ethanol concentration in the blend. Heat flux to the wall increased with increase in ethanol percentage in the blend and at higher initial pressures. Whereas the wall heat flux decreased with an increase in dilution. Unburned Hydrocarbon (UHC) and CO % was also found to decrease with ethanol concentration in the blend.

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ight standard inbred mouse strains were evaluated for ethanol effects on a refined battery of behavioral tests in a study that was originally designed to assess the influence of rat odors in the colony on mouse behaviors. As part of the design of the study, two experimenters conducted the tests, and the study was carefully balanced so that equal numbers of mice in all groups and times of day were tested by each experimenter. A defect in airflow in the facility compromised the odor manipulation, and in fact the different odor exposure groups did not differ in their behaviors. The two experimenters, however, obtained markedly different results for three of the tests. Certain of the experimenter effects arose from the way they judged behaviors that were not automated and had to be rated by the experimenter, such as slips on the balance beam. Others were not evident prior to ethanol injection but had a major influence after the injection. For several measures, the experimenter effects were notably different for different inbred strains. Methods to evaluate and reduce the impact of experimenter effects in future research are discussed.

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Ocean acidification, recognized as a major threat to marine ecosystems, has developed into one of the fastest growing fields of research in marine sciences. Several studies on fish larval stages point to abnormal behaviours, malformations and increased mortality rates as a result of exposure to increased levels of CO2. However, other studies fail to recognize any consequence, suggesting species-specific sensitivity to increased levels of CO2, highlighting the need of further research. In this study we investigated the effects of exposure to elevated pCO2 on behaviour, development, oxidative stress and energy metabolism of sand smelt larvae, Atherina presbyter. Larvae were caught at Arrbida Marine Park (Portugal) and exposed to different pCO2 levels (control: 600 atm, pH = 8.03; medium: 1000 atm, pH = 7.85; high: 1800 atm, pH = 7.64) up to 15 days, after which critical swimming speed (Ucrit), morphometric traits and biochemical biomarkers were determined. Measured biomarkers were related with: 1) oxidative stress-superoxide dismutase and catalase enzyme activities, levels of lipid peroxidation and DNA damage, and levels of superoxide anion production; 2) energy metabolism - total carbohydrate levels, electron transport system activity, lactate dehydrogenase and isocitrate dehydrogenase enzyme activities. Swimming speed was not affected by treatment, but exposure to increasing levels of pCO2 leads to higher energetic costs and morphometric changes, with larger larvae in high pCO2 treatment and smaller larvae in medium pCO2 treatment. The efficient antioxidant response capacity and increase in energetic metabolism only registered at the medium pCO2 treatment may indicate that at higher pCO2 levels the capacity of larvae to restore their internal balance can be impaired. Our findings illustrate the need of using multiple approaches to explore the consequences of future pCO2 levels on organisms.

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A major problem in treating alcohol use disorders (AUDs) is the high rate of relapse due to stress and re-exposure to cues or an environment previously associated with alcohol use. Stressors can induce relapse to alcohol-seeking in humans or reinstatement in rodents. Delta opioid peptide receptors (DOP-Rs) play a role in cue-induced reinstatement of ethanol-seeking; however, their role in stress-induced reinstatement of ethanol-seeking is not known. The objective of this study was to determine the role of DOP-Rs in yohimbine-stress-induced reinstatement of ethanol-seeking. Male, Long-Evans rats were trained to self-administer 10% ethanol in daily 30-minute operant self-administration sessions using a FR3 schedule of reinforcement, followed by extinction training. Once extinction criteria were met, we examined the effects of the DOP-R antagonist, SoRI-9409 (05 mg/kg, i.p.) on yohimbine (2 mg/kg, i.p.) stress-induced reinstatement. Additionally, DOP-R-stimulated [35S]GTPS binding was measured in brain membranes and plasma levels of corticosterone (CORT) were determined. Pre-treatment with SoRI-9409 decreased yohimbine stress-induced reinstatement of ethanol-seeking but did not affect yohimbine-induced increases in plasma CORT levels. Additionally, yohimbine increased DOP-R-stimulated 35[S]GTPS binding in brain membranes of ethanol-trained rats, an effect that was inhibited by SoRI-9409. This suggests that the DOP-R plays an important role in yohimbine-stress-induced reinstatement of ethanol-seeking behavior, and DOP-R antagonists may be promising candidates for further development as a treatment for AUDs.

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This investigation examined physiological and performance effects of cooling on recovery of medium-fast bowlers in the heat. Eight, medium-fast bowlers completed two randomised trials, involving two sessions completed on consecutive days (Session 1: 10-overs and Session 2: 4-overs) in 31 3C and 55 17% relative humidity. Recovery interventions were administered for 20 min (mixed-method cooling vs. control) after Session 1. Measures included bowling performance (ball speed, accuracy, run-up speeds), physical demands (global positioning system, counter-movement jump), physiological (heart rate, core temperature, skin temperature, sweat loss), biochemical (creatine kinase, C-reactive protein) and perceptual variables (perceived exertion, thermal sensation, muscle soreness). Mean ball speed was higher after cooling in Session 2 (118.9 8.1 vs. 115.5 8.6 km h1; P = 0.001; d = 0.67), reducing declines in ball speed between sessions (0.24 vs. 3.18 km h1; P = 0.03; d = 1.80). Large effects indicated higher accuracy in Session 2 after cooling (46.0 11.2 vs. 39.4 8.6 arbitrary units [AU]; P = 0.13; d = 0.93) without affecting total run-up speed (19.0 3.1 vs. 19.0 2.5 km h1; P = 0.97; d = 0.01). Cooling reduced core temperature, skin temperature and thermal sensation throughout the intervention (P = 0.0010.05; d = 1.315.78) and attenuated creatine kinase (P = 0.04; d = 0.56) and muscle soreness at 24-h (P = 0.03; d = 2.05). Accordingly, mixed-method cooling can reduce thermal strain after a 10-over spell and improve markers of muscular damage and discomfort alongside maintained medium-fast bowling performance on consecutive days in hot conditions.