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951.
Elena Suárez‐Bonnet Magda Carvajal Ignacio Méndez‐Ramírez Pável Castillo‐Urueta Josefina Cortés‐Eslava Sandra Gómez‐Arroyo José María Melero‐Vara 《Journal of food science》2013,78(11):T1822-T1829
Rice is an important cereal but it is often contaminated with aflatoxins (AFs). The purpose of this study was to identify and quantify AF (B1, B2, G1, and G2) in 67 rice samples cultivated in Mexico and Spain, and from imported crops collected in 2008 and 2009. The methodology was validated, the rice samples were concentrated and purified with immunoaffinity columns and were quantified by high‐pressure liquid chromatography (HPLC). The average total AF (AFt) in the Spanish rice was 37.3 μg/kg, the range was from 1.6 to 1383 μg/kg, the most contaminated samples being from San Juan de Aznalfarache, Sevilla (AFt = 138.6 μg/kg), from Tortosa, Tarragona (AFt = 104.6 μg/kg), and Calasparra, Murcia (AFt = 103.9 μg/kg). The rice imported from France to Spain had AFt of 26.6 μg/kg and from Pakistan AFt of 18.4 μg/kg, showing less AF contamination than the local one. The rice which originated from Mexico contained (AFt = 16.9 μg/kg), and those imported from the United States (AFt = 14.4 μg/kg) and Uruguay (AFt = 15.6 μg/kg). The imported rice had better quality in terms of the presence of AFs. 相似文献
952.
In early 2002, the Swedish National Food Administration reported high acrylamide levels in heat-treated carbohydrate-rich foods. Consequently, intensive activity began examining the many different types of food, and thousands of analyses have been undertaken world wide. Measurement data have been published in many different types of media. Within this flood of publications, there are only a limited number of articles concerned with the technical aspects of the measurements. This review focuses on the state-of-the-art in the analysis of acrylamide in foodstuffs. It covers information on methods from peer-reviewed articles and other sources (e.g. a survey carried out among official and private laboratories of the Member States of the European Union). Alternative methods are presented and discussed alongside the more common measurement techniques for acrylamide in foodstuffs. Special attention is given to sample preparation. The greatest differences between the analytical methods was for acrylamide extraction and clean-up. The influence of different extraction techniques or extraction solvents/solvent mixtures on the measurement results has not yet been fully investigated. There is also a lack of understanding about the sample clean-up. Since both might have a large impact on the results of the analysis, this review should also be considered as a basis for further investigations. 相似文献
953.
Francisco Chenlo Ramón Moreira Diego M. Prieto María D. Torres 《Food and Bioprocess Technology》2011,4(8):1497-1504
The desorption isotherms of chestnut flour and chestnut starch were determined at different temperatures (20°C, 35°C, 50°C,
and 65°C) using gravimetric method. Desorption isotherms of potato starch were also determined in order to establish a comparison
against desorption isotherms of chestnut starch. Several saturated salt solutions were selected to generate different water
activities in the range of 0.09 to 0.91. Obtained desorption isotherms were of type II, according to Brunauer’s classification.
Three-parameter Brunauer–Emmett–Teller and Guggenheim–Anderson–de Boer (GAB) models satisfactorily fitted the experimental
data for all systems studies, although the last one can be considered better based on obtained statistical parameters and
because it is applicable in a broader water activity range. The average monolayer moisture content (kilograms per kilogram
d.b.) calculated by GAB model was 0.059 ± 0.007 for chestnut flour, 0.103 ± 0.021 for chestnut starch, and 0.060 ± 0.028 for
potato starch. The net isosteric sorption heat, calculated by means of Clausius–Clapeyron equation, decreased when moisture
content increased. The maximum values of net isosteric sorption heat (kilojoules per mole) were approximately 27.5 for chestnut
flour, 16.0 for chestnut starch, and 33.0 for potato starch in the range of temperature from 20°C to 50°C. 相似文献
954.
Beatriz Cardees Irene Clares Tamara Bezos Víctor Toribio Soraya Lpez-Martín Almudena Rocha Hctor Peinado María Yez-M Carlos Cabaas 《International journal of molecular sciences》2022,23(10)
Colorectal cancer (CRC) and ovarian cancer (OvC) patients frequently develop peritoneal metastasis, a condition associated with a very poor prognosis. In these cancers, tumor-derived extracellular vesicles (EVs) cause immunosuppression, facilitate the direct attachment and invasion of cancer cells through the mesothelium, induce the conversion of peritoneal mesothelial cells (PMCs) into cancer-associated fibroblasts (CAFs) and transfer a more aggressive phenotype amongst cancer cells. Although the promoting role of EVs in CRC and OvC peritoneal metastasis is well established, the specific molecules that mediate the interactions between tumor-derived EVs and immune and non-immune target cells remain elusive. Here, we employed the SKOV-3 (ovarian adenocarcinoma) and Colo-320 (colorectal adenocarcinoma) human cell lines as model systems to study the interactions and uptake of EVs produced by ovarian carcinoma and colorectal carcinoma cells, respectively. We established that the adhesion molecule ALCAM/CD166 is involved in the interaction of cancer-derived EVs with recipient cancer cells (a process termed “EV binding” or “EV docking”) and in their subsequent uptake by these cells. The identification of ALCAM/CD166 as a molecule mediating the docking and uptake of CRC and OvC-derived EVs may be potentially exploited to block the peritoneal metastasis cascade promoted by EVs in CRC and OvC patients. 相似文献
955.
This paper presents a simultaneous equations model of crash frequencies by severity level for freeway sections using five-year crash severity frequency data for 275 multilane freeway segments in the State of Washington. Crash severity is a subject of much interest in the context of freeway safety due to higher speeds of travel on freeways and the desire of transportation professionals to implement measures that could potentially reduce crash severity on such facilities. This paper applies a joint Poisson regression model with multivariate normal heterogeneities using the method of Maximum Simulated Likelihood Estimation (MSLE). MSLE serves as a computationally viable alternative to the Bayesian approach that has been adopted in the literature for estimating multivariate simultaneous equations models of crash frequencies. The empirical results presented in this paper suggest the presence of statistically significant error correlations across crash frequencies by severity level. The significant error correlations point to the presence of common unobserved factors related to driver behavior and roadway, traffic and environmental characteristics that influence crash frequencies of different severity levels. It is found that the joint Poisson regression model can improve the efficiency of most model coefficient estimators by reducing their standard deviations. In addition, the empirical results show that observed factors generally do not have the same impact on crash frequencies at different levels of severity. 相似文献
956.
Patricia Teixeira Santana Siane Lopes Bittencourt Rosas Beatriz Elias Ribeiro Ygor Marinho Heitor S. P. de Souza 《International journal of molecular sciences》2022,23(7)
Microbe–host communication is essential to maintain vital functions of a healthy host, and its disruption has been associated with several diseases, including Crohn’s disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD). Although individual members of the intestinal microbiota have been associated with experimental IBD, identifying microorganisms that affect disease susceptibility and phenotypes in humans remains a considerable challenge. Currently, the lack of a definition between what is healthy and what is a dysbiotic gut microbiome limits research. Nevertheless, although clear proof-of-concept of causality is still lacking, there is an increasingly evident need to understand the microbial basis of IBD at the microbial strain, genomic, epigenomic, and functional levels and in specific clinical contexts. Recent information on the role of diet and novel environmental risk factors affecting the gut microbiome has direct implications for the immune response that impacts the development of IBD. The complexity of IBD pathogenesis, involving multiple distinct elements, suggests the need for an integrative approach, likely utilizing computational modeling of molecular datasets to identify more specific therapeutic targets. 相似文献
957.
Mirta García-Martínez Leonardo M. Cortez Alicia Otero Marina Betancor Beatriz Serrano-Prez Rosa Bolea Juan J. Badiola María Carmen Garza 《International journal of molecular sciences》2022,23(7)
Prion diseases are chronic and fatal neurodegenerative diseases characterized by the accumulation of disease-specific prion protein (PrPSc), spongiform changes, neuronal loss, and gliosis. Growing evidence shows that the neuroinflammatory response is a key component of prion diseases and contributes to neurodegeneration. Toll-like receptors (TLRs) have been proposed as important mediators of innate immune responses triggered in the central nervous system in other human neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis. However, little is known about the role of TLRs in prion diseases, and their involvement in the neuropathology of natural scrapie has not been studied. We assessed the gene expression of ovine TLRs in four anatomically distinct brain regions in natural scrapie-infected sheep and evaluated the possible correlations between gene expression and the pathological hallmarks of prion disease. We observed significant changes in TLR expression in scrapie-infected sheep that correlate with the degree of spongiosis, PrPSc deposition, and gliosis in each of the regions studied. Remarkably, TLR4 was the only gene upregulated in all regions, regardless of the severity of neuropathology. In the hippocampus, we observed milder neuropathology associated with a distinct TLR gene expression profile and the presence of a peculiar microglial morphology, called rod microglia, described here for the first time in the brain of scrapie-infected sheep. The concurrence of these features suggests partial neuroprotection of the hippocampus. Finally, a comparison of the findings in naturallyinfected sheep versus an ovinized mouse model (tg338 mice) revealed distinct patterns of TLRgene expression. 相似文献
958.
Katya Georgieva Gergana Mihailova Beatriz Fernndez-Marín Gianpaolo Bertazza Annalisa Govoni Miren Irati Arzac Jos Manuel Laza Jos Luis Vilas Jos Ignacio García-Plazaola Francesca Rapparini 《International journal of molecular sciences》2022,23(23)
Resurrection plants are able to deal with complete dehydration of their leaves and then recover normal metabolic activity after rehydration. Only a few resurrection species are exposed to freezing temperatures in their natural environments, making them interesting models to study the key metabolic adjustments of freezing tolerances. Here, we investigate the effect of cold and freezing temperatures on physiological and biochemical changes in the leaves of Haberlea rhodopensis under natural and controlled environmental conditions. Our data shows that leaf water content affects its thermodynamical properties during vitrification under low temperatures. The changes in membrane lipid composition, accumulation of sugars, and synthesis of stress-induced proteins were significantly activated during the adaptation of H. rhodopensis to both cold and freezing temperatures. In particular, the freezing tolerance of H. rhodopensis relies on a sucrose/hexoses ratio in favor of hexoses during cold acclimation, while there is a shift in favor of sucrose upon exposure to freezing temperatures, especially evident when leaf desiccation is relevant. This pattern was paralleled by an elevated ratio of unsaturated/saturated fatty acids and significant quantitative and compositional changes in stress-induced proteins, namely dehydrins and early light-induced proteins (ELIPs). Taken together, our data indicate that common responses of H. rhodopensis plants to low temperature and desiccation involve the accumulation of sugars and upregulation of dehydrins/ELIP protein expression. Further studies on the molecular mechanisms underlying freezing tolerance (genes and genetic regulatory mechanisms) may help breeders to improve the resistance of crop plants. 相似文献
959.
Raquel Sanabria-de la Torre Cristina García-Fontana Sheila Gonzlez-Salvatierra Francisco Andújar-Vera Luis Martínez-Heredia Beatriz García-Fontana Manuel Muoz-Torres 《International journal of molecular sciences》2022,23(13)
Vascular complications are the leading cause of morbidity and mortality among patients with type 2 diabetes mellitus (T2DM). These vascular abnormalities result in a chronic hyperglycemic state, which influences many signaling molecular pathways that initially lead to increased oxidative stress, increased inflammation, and endothelial dysfunction, leading to both microvascular and macrovascular complications. Endothelial dysfunction represents the initial stage in both types of vascular complications; it represents “mandatory damage” in the development of microvascular complications and only “introductory damage” in the development of macrovascular complications. Increasing scientific evidence has revealed an important role of the Wnt pathway in the pathophysiology of the vascular wall. It is well known that the Wnt pathway is altered in patients with T2DM. This review aims to be an update of the current literature related to the Wnt pathway molecules that are altered in patients with T2DM, which may also be the cause of damage to the vasculature. Both microvascular complications (retinopathy, nephropathy, and neuropathy) and macrovascular complications (coronary artery disease, cerebrovascular disease, and peripheral arterial disease) are analyzed. This review aims to concisely concentrate all the evidence to facilitate the view on the vascular involvement of the Wnt pathway and its components by highlighting the importance of exploring possible therapeutic strategy for patients with T2DM who develop vascular pathologies. 相似文献
960.
Miguel Angel Roncoroni Pedro Romero Jesús Montes Guido Bascialla Rosario Rodríguez Ramón Rodríguez Pons-Esparver Luis Felipe Mazadiego María Flor García-Mayoral 《石油科学(英文版)》2021,(5):1409-1426
This work presents the design of a robust foam formulation that tolerates harsh reservoir conditions(high salinity,high divalent ion concentration,high temperat... 相似文献