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501.
Volatiles in leaf extracts of Lycopersicon hirsutum f. glabratum disrupted settled Macrosiphum euphorbiae and caused 100% mortality over 24 hr. There was a single peak of activity among fractions separated by silica gel column chromatography. 2-Tridecanone was the major component of all active fractions, and responses to 2-tridecanone alone were similar to the initial extract. Another major component, 2-undecanone had no effect on M. euphorbiae either alone or as a synergist of 2-tridecanone. Trichome exudates and 2-tridecanone applied to artificial membranes inhibited feeding and caused mortality over 24 hr. Topical LD50 for 2-tridecanone was 1.0 μg/individual. The lab colony displayed little variation in susceptibility to 2-tridecanone. The effectiveness of 2-tridecanone in reducing infestation by M. euphorbiae and evidence of behavioral resistance in M. euphorbiae to 2-tridecanone are discussed. 相似文献
502.
Antonella Calabretti Francesca Cateni Giuseppe Procida Luciana Gabrielli Favretto 《Journal of the science of food and agriculture》2003,83(14):1493-1498
The adaptative changes in the fatty acid composition of the main lipid classes in rainbow trout (Oncorhynchus mykiss) edible flesh in response to environmental variation in water temperature were investigated. The research was carried out on intensively farmed trout sampled at different times of the year. Neutral lipids (NL), phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were separated using flash chromatography. Compared with summer acclimatisation, a decrease in neutral lipids of about 19% was observed in winter, accompanied by increases in phosphatidylethanolamine and phosphatidylcholine of about 41 and 29%, respectively. The metabolic adjustment in cold adaptation caused an increase in the levels of unsaturated fatty acids and monoenes of the oleic acid ω9 family and an increase in the levels of unsaturated fatty acids of the linoleic acid ω3 family. At the same time a reduction in the levels of saturated and monounsaturated fatty acids of the oleic acid ω9 family was observed. This pattern turned out to be particularly evident in phosphatidylcholine. The net result of these changes in composition was a significant increase in the polyunsaturated/saturated and polyunsaturated/monoenic fatty acid ratios in the edible flesh. Copyright © 2003 Society of Chemical Industry 相似文献
503.
504.
Roberta Piovesana Michael Sebastian Salazar Intriago Luciana Dini Ada Maria Tata 《International journal of molecular sciences》2021,22(9)
All nervous system pathologies (e.g., neurodegenerative/demyelinating diseases and brain tumours) develop neuroinflammation, a beneficial process during pathological events, aimed at removing damaged cells, toxic agents, and/or pathogens. Unfortunately, excessive inflammation frequently occurs during nervous system disorders, becoming a detrimental event capable of enhancing neurons and myelinating glial cell impairment, rather than improving their survival and activity. Consequently, targeting the neuroinflammation could be relevant for reducing brain injury and rescuing neuronal and glial cell functions. Several studies have highlighted the role of acetylcholine and its receptors in the regulation of central and peripheral inflammation. In particular, α7 nicotinic receptor has been described as one of the main regulators of the “brain cholinergic anti-inflammatory pathway”. Its expression in astrocytes and microglial cells and the ability to modulate anti-inflammatory cytokines make this receptor a new interesting therapeutic target for neuroinflammation regulation. In this review, we summarize the distribution and physiological functions of the α7 nicotinic receptor in glial cells (astrocytes and microglia) and its role in the modulation of neuroinflammation. Moreover, we explore how its altered expression and function contribute to the development of different neurological pathologies and exacerbate neuroinflammatory processes. 相似文献
505.
Aurealice Rosa Maria Martins Isaias Donizeti Silva Luciana Machado-Santos Rafael Pino Vitti Mário Alexandre Coelho Sinhoreti William Cunha Brandt 《应用聚合物科学杂志》2021,138(21):50498
The aim of this study was to evaluate the effects of isobornyl methacrylate (IBOMA) as a diluent co-monomer on the physical properties of experimental resins. Blends of bisphenol glycidyl methacrylate (Bis-GMA) were formulated with triethylene glycol dimethacrylate (TEGDMA) and IBOMA in different wt%. The degree of conversion, flexural strength, elastic modulus, and ultimate tensile strength were determined. Immediate and 24 h volumetric shrinkage were calculated. Data were submitted to ANOVA and Tukey's tests (α = 0.05). Blends of Bis-GMA and IBOMA showed the lowest ultimate tensile strength, flexural strength, elastic modulus, degree of conversion, and immediate and 24 h volumetric shrinkage results. However, when IBOMA was used together with TEGDMA in blends of Bis-GMA, the resin composites showed best curing performance and high physical-mechanical properties. Thus, the IBOMA is as diluent co-monomer that can be used in dental resin composites to reduce the volumetric shrinkage. 相似文献
506.
Marta Razum Luka Pavić Luciana Ghussn Andrea Moguš-Milanković Ana Šantić 《Journal of the American Ceramic Society》2021,104(9):4669-4678
The influence of Nb2O5 on the structure and ionic conductivity of potassium phosphate glasses was investigated in glasses with composition xNb2O5–(100-x)[0.45K2O–0.55P2O5], x = 10–47 mol%. The Raman spectra of glasses reveal a transition from predominantly orthophosphate to predominantly niobate glass network with increasing Nb2O5 content. In the glass structure, niobium forms NbO6 octahedra which are interlinked with phosphate units for the glass containing 10 mol% Nb2O5, but for higher Nb2O5 content they become mutually interconnected via Nb-O-Nb bonds. The transport of potassium ions was found to be strongly dependent on the structural characteristics of the glass network. While the mixed niobate-phosphate glass network hinders the diffusion of potassium ions by providing traps that immobilize them and/or by blocking the conduction pathways, predominantly niobate glass network exhibits a rather facilitating effect which is evidenced in the trend of DC conductivity as well as in the features of the frequency-dependent conductivity and typical hopping lengths of potassium ions. 相似文献
507.
Luciana Lordêlo Nascimento Jéssica Magalhães Neves Nunes Plínio Ribeiro Rodrigues Janice Izabel Druzian 《应用聚合物科学杂志》2018,135(19)
The aim of this study is to evaluate the bioconversion of residual soybean oil (RSO) into polyhydroxyalkanoates (PHAs) by selecting microorganism and fermentation condition in order to increase PHAs production. PHAs production by Cupriavidus necator IPT 026 using glucose (PHA 1) and RSO (PHA 2) as substrate is 1.15 ± 0.21 and 2.84 ± 0.04 g L?1, respectively. FTIR spectra of PHAs were similar to data reported in literature. PHAs presented low crystallinity (PHA 1: 42.69%; PHA 2: 46.44%), high thermal stability (PHA 1: 271.78 °C; PHA 2: 272.52 °C), and low MW (PHA 1: 140.69 kDa; PHA 2: 254.54 kDa). PHAs produced by RSO are potential candidates for industrial applications, especially ones that demand higher temperatures. This is the first study on the production and characterization of PHAs obtained by C. necator IPT 026 in culture with RSO. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46255. 相似文献
508.
Paraquat-loaded alginate/chitosan nanoparticles: preparation, characterization and soil sorption studies 总被引:1,自引:0,他引:1
Silva Mdos S Cocenza DS Grillo R de Melo NF Tonello PS de Oliveira LC Cassimiro DL Rosa AH Fraceto LF 《Journal of hazardous materials》2011,190(1-3):366-374
Agrochemicals are amongst the contaminants most widely encountered in surface and subterranean hydrological systems. They comprise a variety of molecules, with properties that confer differing degrees of persistence and mobility in the environment, as well as different toxic, carcinogenic, mutagenic and teratogenic potentials, which can affect non-target organisms including man. In this work, alginate/chitosan nanoparticles were prepared as a carrier system for the herbicide paraquat. The preparation and physico-chemical characterization of the nanoparticles was followed by evaluation of zeta potential, pH, size and polydispersion. The techniques employed included transmission electron microscopy, differential scanning calorimetry and Fourier transform infrared spectroscopy. The formulation presented a size distribution of 635 ± 12 nm, polydispersion of 0.518, zeta potential of -22.8 ± 2.3 mV and association efficiency of 74.2%. There were significant differences between the release profiles of free paraquat and the herbicide associated with the alginate/chitosan nanoparticles. Tests showed that soil sorption of paraquat, either free or associated with the nanoparticles, was dependent on the quantity of organic matter present. The results presented in this work show that association of paraquat with alginate/chitosan nanoparticles alters the release profile of the herbicide, as well as its interaction with the soil, indicating that this system could be an effective means of reducing negative impacts caused by paraquat. 相似文献
509.
Luciana A.R.S. Lima Susana JohannPatrícia S. Cisalpino Lúcia P.S. PimentaMaria Amélia D. Boaventura 《Food research international (Ottawa, Ont.)》2011,44(7):2283-2288
In this study, 9-hydroxy-folianin and sucrose octaacetate were isolated from the seed ethanol extract of Annona cornifolia A. St. -Hil. (Annonaceae). We found that 9-hydroxy-folianin was able to inhibit several clinical strains of the pathogenic fungus Paracoccidioides brasiliensis. The minimal inhibitory concentrations of 9-hydroxy-folianin against twelve clinical strains of P. brasiliensis were found to be in the range between 3.4 and 27.7 ??g mL−1 and were much more potent than the commercial antifungal trimethropin-sulfamethoxazole. P. brasiliensis isolates (Pb-18, Pb-11, Pb-01, Pb-B339, Pb-8 and Pb-18 virulent) were also susceptible to sucrose octaacetate. The growth of Candida albicans, C. tropicalis, C. parapsilosis and Cryptococcus gattii were not affected by these compounds. Sucrose octaacetate and 9-hydroxy-folianin showed no effects with amphotericin B and trimethropin-sulfamethoxazole, but they displayed a synergetic effect with itraconazole. 相似文献
510.
Luciana Sartore Fabio Bignotti Stefano Pandini Alberto D'Amore Luca Di Landro 《Polymer Composites》2016,37(12):3416-3422
Blends based on protein hydrolysate (PH), derived from waste products of the leather industry, and poly(ethylene‐co‐vinyl acetate) (EVA), were obtained by reactive blending and their physico‐chemical properties as well as their mechanical and rheological behavior were evaluated. The effect of vinyl acetate content and of a transesterification agent added to increase interaction between polymer and bio‐based components were investigated. Novel biodegradable polymeric materials for spray mulching coatings were also obtained from hydrolyzed proteins and end‐functionalized poly(ethylene glycol) (PEG), which was used as crosslinking agent. These products, almost entirely obtained from renewable sources, represent a new type of biodegradable material which looks promising for several applications, for instance in packaging or in agriculture as transplanting or mulching films with additional fertilizing action of PH. POLYM. COMPOS., 37:3416–3422, 2016. © 2015 Society of Plastics Engineers 相似文献