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51.
Rosane Lopes Crizel Jessica Fernanda Hoffmann Giovana Paula Zandon Paula Mendona Shild Lobo Rogerio Oliveira Jorge Fabio Clasen Chaves 《European Journal of Lipid Science and Technology》2020,122(4)
Six olive oils extracted from the cultivars Arbequina, Arbosana, Coratina, Frantoio, Koroneiki, and Picual from 2017 and 2018 harvests, cultivated in Pinheiro Machado, Rio Grande do Sul, Brazil, are evaluated for standard oil composition parameters and bioactive constituents (pigments, tocopherols, and phenolic compounds). Multivariate principal component analysis (PCA) and univariate ANOVA and Fisher's LSD test are used to verify the effect of cultivar and harvest year on oil composition. Olive oil composition met extra virgin olive oil (EVOO) standard parameters and is influenced by both cultivar and harvest year. EVOO produced in 2018 has greater chlorophyll, caffeic acid, ligstroside aglycone, hydroxyoleuropein aglycone, syringic acid, and hydroxytyrosol acetate contents than the EVOOs from 2017. Linoleic acid, ferulic acid, ligstroside aglycone, and hydroxytyrosol acetate are the variables whose contents most contributed to the differentiation of oils by cultivar in both harvest years. Chemical characterization analyses allow for the differentiation of oil composition based on harvest year and cultivar. Metabolic quality data obtained here support the establishment of a local EVOO profile and the compounds that most contributed to treatment differentiation may serve as markers that can be utilized in determining origin, cultivar, and harvest year. Practical Applications: Olive production in Brazil is recent and is based on European cultivars which have not been bred for the local environmental conditions. Therefore, the measurement of olive oil metabolic quality will determine cultivar adaptability to local edaphoclimatic conditions as well as assist in the establishment of a standard of identity for the product and promote the development of its market. Olive oil produced in Southern Brazil shows high quality, and is especially rich in phenolic compounds. Although harvest year influences oil composition, oil from both harvests meet EVOO standards and cultivar specific metabolic markers are observed. This study provides the foundation for olive producers in Southern Brazil to seek authentication of the geographical origin of olive oil. 相似文献
52.
Reiner JL O'Connell SG Moors AJ Kucklick JR Becker PR Keller JM 《Environmental science & technology》2011,45(19):8129-8136
Wildlife from remote locations have been shown to bioaccumulate perfluorinated compounds (PFCs) in their tissues. Twelve PFCs, consisting of perfluorinated carboxylic (PFCA) and sulfonic (PFSA) acids as well as the perfluorooctane sulfonate (PFOS) precursor perfluorooctane sulfonamide (PFOSA), were measured in livers of 68 beluga whales (Delphinapterus leucas) collected from two subpopulations, Cook Inlet and eastern Chukchi Sea, in Alaska between 1989 and 2006. PFOS and PFOSA were the dominant compounds measured in both beluga stock populations, with overall median concentrations of 10.8 ng/g and 22.8 ng/g, respectively. Long-chain perfluorocarboxylates, PFCAs (9 to 14 carbons), were detected in more than 80% of the samples. Perfluoroundecanoic acid (PFUnA) and perfluorotridecanoic acid (PFTriA) made up a large percentage of the PFCAs measured with median concentrations of 8.49 ng/g and 4.38 ng/g, respectively. To compare differences in location, year, sex, and length, backward stepwise multiple regression models of the individual and total PFC concentrations were used. Spatially, the Cook Inlet belugas had higher concentrations of most PFCAs and PFOS (p < 0.05); however, these belugas had a lower median concentration of PFOSA when compared to belugas from the eastern Chukchi Sea (p < 0.05). Temporal trends indicated most PFCAs, PFHxS, PFOS, and PFOSA concentrations increased from 1989 to 2006 (p < 0.05). Males had significantly higher concentrations of PFTriA, ΣPFCA, and PFOS (p < 0.05). Perfluorononanic acid (PFNA) and PFOS showed a significant decrease in concentration with increasing animal length (p < 0.05). These observations suggest the accumulation of PFCs in belugas is influenced by year, location, sex, and length. 相似文献
53.
54.
Lieffers JR Hanning RM 《Revue canadienne de la pratique et de la recherche en diététique》2012,73(3):142
Nutrition applications for mobile devices (e.g., personal digital assistants, smartphones) are becoming increasingly accessible and can assist with the difficult task of intake recording for dietary assessment and self-monitoring. This review is a compilation and discussion of research on this tool for dietary intake documentation in healthy populations and those trying to lose weight. The purpose is to compare this tool with conventional methods (e.g., 24-hour recall interviews, paper-based food records). Research databases were searched from January 2000 to April 2011, with the following criteria: healthy or weight loss populations, use of a mobile device nutrition application, and inclusion of at least one of three measures, which were the ability to capture dietary intake in comparison with conventional methods, dietary self-monitoring adherence, and changes in anthropometrics and/or dietary intake. Eighteen studies are discussed. Two application categories were identified: those with which users select food and portion size from databases and those with which users photograph their food. Overall, positive feedback was reported with applications. Both application types had moderate to good correlations for assessing energy and nutrient intakes in comparison with conventional methods. For self-monitoring, applications versus conventional techniques (often paper records) frequently resulted in better self-monitoring adherence, and changes in dietary intake and/or anthropometrics. Nutrition applications for mobile devices have an exciting potential for use in dietetic practice. 相似文献
55.
56.
Nordstrom JL Rangdale R Vickery MC Phillips AM Murray SL Wagley S DePaola A 《Journal of food protection》2006,69(11):2770-2772
Reliable methods are needed to detect total and pathogenic Vibrio parahaemolyticus. One marker of V. parahaemolyticus virulence is the thermostable-related hemolysin. We developed an alkaline phosphatase-labeled DNA probe method for the specific detection and enumeration of trh-positive V. parahaemolyticus by colony hybridization. The probe was tested against a panel of 200 bacterial strains and determined to be specific for trh-positive V. parahaemolyticus. Additionally, the trh alkaline phosphatase probe colony hybridization was successfully used to detect and enumerate trh-positive V. parahaemolyticus in seafood and water samples collected from the United States and the United Kingdom. 相似文献
57.
Quantification of histamine-producing bacteria (HPB) is necessary in order to elucidate the role that HPB play in scombrotoxin (histamine) fish poisoning. We report here the evaluation of a real-time PCR method for the quantification of total and specific Gram-negative HPB species in fish using a most probable number (MPN) format. The species-specific real-time PCR assay was 100% inclusive for independently detecting Morganella morganii, Enterobacter aerogenes, Raoultella planticola/ornithinolytica and Photobacterium damselae and did not cross react with other histamine- or non- histamine-producing bacteria. The efficiency of the reactions in the absence and presence of Spanish mackerel enrichment containing 1 × 106 CFU/ml of background microflora were 93-104 and 92-99%, respectively. The MPN-real-time PCR assay accurately quantified total and specific HPB in spiked mahi-mahi (Coryphaena hippurus) and Spanish mackerel (Scomberomorus maculates) samples. These methods were used to quantify total and specific HPB in naturally contaminated, decomposing mahi-mahi, Spanish mackerel and tuna (Thunnus albacares) samples. The results of this study indicate that MPN-real-time PCR assays can be used to accurately enumerate total and specific HPB in fish samples. These assays can be applied to assess the effectiveness of mitigation strategies and understand the relationship between HPB and histamine production in decomposing fish. 相似文献
58.
Dr. Jessica S. Kelsey Dr. Tamas Geczy Nancy E. Lewin Dr. Noemi Kedei Colin S. Hill Julia S. Selezneva Christopher J. Valle Wonhee Woo Dr. Inna Gorshkova Dr. Peter M. Blumberg 《Chembiochem : a European journal of chemical biology》2014,15(8):1131-1144
The C1 domain, which represents the recognition motif on protein kinase C for the lipophilic second messenger diacylglycerol and its ultrapotent analogues, the phorbol esters, has emerged as a promising therapeutic target for cancer and other indications. Potential target selectivity is markedly enhanced both because binding reflects ternary complex formation between the ligand, C1 domain, and phospholipid, and because binding drives membrane insertion of the C1 domain, permitting aspects of the C1 domain surface outside the binding site, per se, to influence binding energetics. Here, focusing on charged residues identified in atypical C1 domains which contribute to their loss of ligand binding activity, we showed that increasing charge along the rim of the binding cleft of the protein kinase C δ C1 b domain raises the requirement for anionic phospholipids. Correspondingly, it shifts the selectivity of C1 domain translocation to the plasma membrane, which is more negatively charged than internal membranes. This change in localization is most pronounced in the case of more hydrophilic ligands, which provide weaker membrane stabilization than do the more hydrophobic ligands and thus contributes an element to the structure–activity relations for C1 domain ligands. Coexpressing pairs of C1‐containing constructs with differing charges each expressing a distinct fluorescent tag provided a powerful tool to demonstrate the effect of increasing charge in the C1 domain. 相似文献
59.
Polymer-derived ceramic composites are being investigated as environmental barrier coatings to protect stainless steel from oxidation and carburization. Coatings have been produced using poly(hydridomethylsiloxane) as a preceramic polymer and titanium disilicide as an expansion agent. Processing parameters have been optimized and a relationship has been derived to predict the final coating thickness based on slurry viscosity and dip coating withdrawal speed. Microstructural analysis reveals a composite coating of oxidized filler particles in a silica matrix. A diffusion layer is visible at the coating–steel interface, indicating good bonding. The optimized coatings are ∼18 μm thick, and have some residual porosity and a density of 2.56 g/cm3 . 相似文献
60.
Natalia Cullell Cristina Gallego-Fbrega Jara Crcel-Mrquez Elena Muio Laia Lluci-Carol Miquel Lleds Jesús M. Martín-Campos Jessica Molina Laura Casas Marta Almeria Israel Fernndez-Cadenas Jerzy Krupinski 《International journal of molecular sciences》2022,23(6)
Small vessel strokes (SVS) and intracerebral haemorrhages (ICH) are acute outcomes of cerebral small vessel disease (SVD). Genetic studies combining both phenotypes have identified three loci associated with both traits. However, the genetic cis-regulation at the protein level associated with SVD has not been studied before. We performed a proteome-wide association study (PWAS) using FUSION to integrate a genome-wide association study (GWAS) and brain proteomic data to discover the common mechanisms regulating both SVS and ICH. Dorsolateral prefrontal cortex (dPFC) brain proteomes from the ROS/MAP study (N = 376 subjects and 1443 proteins) and the summary statistics for the SVS GWAS from the MEGASTROKE study (N = 237,511) and multi-trait analysis of GWAS (MTAG)-ICH–SVS from Chung et al. (N = 240,269) were selected. We performed PWAS and then a co-localization analysis with COLOC. The significant and nominal results were validated using a replication dPFC proteome (N = 152). The replicated results (q-value < 0.05) were further investigated for the causality relationship using summary data-based Mendelian randomization (SMR). One protein (ICA1L) was significantly associated with SVS (z-score = −4.42 and p-value = 9.6 × 10−6) and non-lobar ICH (z-score = −4.8 and p-value = 1.58 × 10−6) in the discovery PWAS, with a high co-localization posterior probability of 4. In the validation PWAS, ICA1L remained significantly associated with both traits. The SMR results for ICA1L indicated a causal association of protein expression levels in the brain with SVS (p-value = 3.66 × 10−5) and non-lobar ICH (p-value = 1.81 × 10−5). Our results show that the association of ICA1L with SVS and non-lobar ICH is conditioned by the cis-regulation of its protein levels in the brain. 相似文献