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991.
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Paola Jiménez-Sotelo Maylet Hernández-Martínez Guillermo Osorio-Revilla Ofelia Gabriela Meza-Márquez Felipe García-Ochoa 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(7):1105-1115
Avocado oil is a high-value and nutraceutical oil whose authentication is very important since the addition of low-cost oils could lower its beneficial properties. Mid-FTIR spectroscopy combined with chemometrics was used to detect and quantify adulteration of avocado oil with sunflower and soybean oils in a ternary mixture. Thirty-seven laboratory-prepared adulterated samples and 20 pure avocado oil samples were evaluated. The adulterated oil amount ranged from 2% to 50% (w/w) in avocado oil. A soft independent modelling class analogy (SIMCA) model was developed to discriminate between pure and adulterated samples. The model showed recognition and rejection rate of 100% and proper classification in external validation. A partial least square (PLS) algorithm was used to estimate the percentage of adulteration. The PLS model showed values of R2 > 0.9961, standard errors of calibration (SEC) in the range of 0.3963–0.7881, standard errors of prediction (SEP estimated) between 0.6483 and 0.9707, and good prediction performances in external validation. The results showed that mid-FTIR spectroscopy could be an accurate and reliable technique for qualitative and quantitative analysis of avocado oil in ternary mixtures. 相似文献
994.
Riccardo Milanesi Farida Tripodi Jacopo Vertemara Renata Tisi Paola Coccetti 《International journal of molecular sciences》2021,22(17)
To achieve growth, microbial organisms must cope with stresses and adapt to the environment, exploiting the available nutrients with the highest efficiency. In Saccharomyces cerevisiae, Ras/PKA and Snf1/AMPK pathways regulate cellular metabolism according to the supply of glucose, alternatively supporting fermentation or mitochondrial respiration. Many reports have highlighted crosstalk between these two pathways, even without providing a comprehensive mechanism of regulation. Here, we show that glucose-dependent inactivation of Snf1/AMPK is independent from the Ras/PKA pathway. Decoupling glucose uptake rate from glucose concentration, we highlight a strong coordination between glycolytic metabolism and Snf1/AMPK, with an inverse correlation between Snf1/AMPK phosphorylation state and glucose uptake rate, regardless of glucose concentration in the medium. Despite fructose-1,6-bisphosphate (F1,6BP) being proposed as a glycolytic flux sensor, we demonstrate that glucose-6-phosphate (G6P), and not F1,6BP, is involved in the control of Snf1/AMPK phosphorylation state. Altogether, this study supports a model by which Snf1/AMPK senses glucose flux independently from PKA activity, and thanks to conversion of glucose into G6P. 相似文献
995.
Paola Arboretto Michele Cillo Antonio Leonardi 《International journal of molecular sciences》2021,22(15)
The transforming growth factor beta (TGF-β) signaling is fundamental for correct embryonic development. However, alterations of this pathway have been correlated with oncogenesis, tumor progression and sustaining of cancer stem cells (CSCs). Cripto-1 (CR-1) and Nodal are two embryonic proteins involved in TGF-β signaling. Their expression is almost undetectable in terminally differentiated cells, but they are often re-expressed in tumor cells, especially in CSCs. Moreover, cancer cells that show high levels of CR-1 and/or Nodal display more aggressive phenotypes in vitro, while in vivo their expression correlates with a worse prognosis in several human cancers. The ability to target CSCs still represents an unmet medical need for the complete eradication of certain types of tumors. Given the prognostic role and the selective expression of CR-1 and Nodal on cancer cells, they represent archetypes for targeted therapy. The aim of this review is to clarify the role of CR-1 and Nodal in cancer stem populations and to summarize the current therapeutic strategy to target CSCs using monoclonal antibodies (mAbs) or other molecular tools to interfere with these two proteins. 相似文献
996.
Tiziana Genovese Rosalba Siracusa Roberta Fusco Ramona DAmico Daniela Impellizzeri Alessio Filippo Peritore Rosalia Crupi Enrico Gugliandolo Rossana Morabito Salvatore Cuzzocrea Angela Trovato Salinaro Marika Cordaro Rosanna Di Paola 《International journal of molecular sciences》2021,22(15)
Background: exposure to environmental contaminants has been linked to an increased risk of neurological diseases and poor outcomes. Chemical name of Atrazine (ATR) is 6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4-diamine, and it is the most commonly used broad-spectrum herbicide in agricultural crops. Several studies have demonstrated that ATR has the potential to be harmful to the brain’s neuronal circuits. Until today nobody has explored the effect of ATR inhalation on young and aged mice. Methods: young and aged mice were subject to 25 mg of ATR in a vehicle made with saline and 10% of Dimethyl sulfoxide (DMSO) every day for 28 days. At the end of experiment different behavioral test were made and brain was collected. Results: exposure to ATR induced the same response in terms of behavioral alterations and motor and memory impairment in mice but in aged group was more marked. Additionally, in both young and aged mice ATR inhalations induced oxidative stress with impairment in physiological antioxidant response, lipid peroxidation, nuclear factor kappa-light-chain-enhancer of activated B cells (nf-κb) pathways activation with consequences of pro-inflammatory cytokines release and apoptosis. However, the older group was shown to be more sensitive to ATR inhalation. Conclusions: our results showed that aged mice were more susceptible compared to young mice to air pollutants exposure, put in place a minor physiologically response was seen when exposed to it. 相似文献
997.
A PCR method for differentiation and detection of the two known ochratoxin A producing Penicillium species, Penicillium verrucosum and Penicillium nordicum has been developed. It is based upon two genes of the ochratoxin A biosynthetic pathway, namely the ochratoxin A polyketide synthase gene (otapksPN) and a non-ribosomal peptide syntethase gene (otanpsPN) from P. nordicum. Both ochratoxin A producing Penicillia differ characteristically in the PCR result, making a taxonomic differentiation possible. P. verrucosum gives consistently only a positive reaction with the primers for the otanpsPN gene, whereas P. nordicum is positive for both genes. The PCR reaction is negative with all of other food related fungal species tested. This PCR system has been used to analyse 62 Penicillium strains isolated from cured meat products or ripening rooms, the natural habitat of P. nordicum. Among the 62 analysed strains 11 (18%) were positive with all specific PCR reactions. All 11 strains were able to produce ochratoxin A. In a RAPD analysis performed in parallel all 11 strains showed a pattern characteristic of P. nordicum, indicating the congruence of all data. None of the other strains isolated from cured meat produced ochratoxin A; most of them (30 out of 62) had a RAPD pattern characteristic for Penicillium nalgiovense. Interestingly some of the P. nalgiovense strains showed weak PCR product bands with varying length after electrophoresis. This was true for both primer pairs. None of these P. nalgiovense strains however produced detectable amounts of ochratoxin A. A more detailed analysis revealed that P. nalgiovense carries similar but non-transcribed sequences to the ochratoxin A biosynthetic genes of P. nordicum. 相似文献
998.
Tetta C David S Marcelli D Cogliati P Formica M Inguaggiato P Panichi V 《Hemodialysis international. International Symposium on Home Hemodialysis》2006,10(Z1):S60-S66
Online hemodiafiltration appears to be the most effective technique of renal replacement therapy in many respects. Removal of small and high-molecular weight substances is enhanced. Modern technology ensures a safe, online production of reinfusion fluids. Nonetheless, stringent maintenance rules are required for the production of sterile and nonpyrogenic-dialysate solutions. In this review, we will critically review the state of the art of the clinical effects derived from the use of ultrapure dialysate and the online production of dialysate fluids in high-flux hemodiafiltration. 相似文献
999.
A fully automated method for lung nodule detection from postero-anterior chest radiographs 总被引:1,自引:0,他引:1
In the past decades, a great deal of research work has been devoted to the development of systems that could improve radiologists' accuracy in detecting lung nodules. Despite the great efforts, the problem is still open. In this paper, we present a fully automated system processing digital postero-anterior (PA) chest radiographs, that starts by producing an accurate segmentation of the lung field area. The segmented lung area includes even those parts of the lungs hidden behind the heart, the spine, and the diaphragm, which are usually excluded from the methods presented in the literature. This decision is motivated by the fact that lung nodules may be found also in these areas. The segmented area is processed with a simple multiscale method that enhances the visibility of the nodules, and an extraction scheme is then applied to select potential nodules. To reduce the high number of false positives extracted, cost-sensitive support vector machines (SVMs) are trained to recognize the true nodules. Different learning experiments were performed on two different data sets, created by means of feature selection, and employing Gaussian and polynomial SVMs trained with different parameters; the results are reported and compared. With the best SVM models, we obtain about 1.5 false positives per image (fp/image) when sensitivity is approximately equal to 0.71; this number increases to about 2.5 and 4 fp/image when sensitivity is = 0.78 and = 0.85, respectively. For the highest sensitivity (= 0.92 and 1.0), we get 7 or 8 fp/image. 相似文献
1000.
Antonella Rosa Paola Scano M. Paola Melis Monica Deiana Angela Atzeri M. Assunta Dessì 《Food chemistry》2009
The lipid composition and oxidative stability of mullet (Mugilcephalus) raw roes and cured products (bottarga) from two different fishing areas have been studied and compared to find lipid modifications due to manufacturing procedures. Moreover, n-3 PUFA oxidation in raw roes and cured products was monitored during storage at −20 °C, and in grated sample of bottarga at room temperature. Oxidative degradation of n-3 PUFA was evaluated by conjugated dienes fatty acids hydroperoxides determination. The treatments on mullet roe did not affect the lipid level (fatty alcohols and acids, cholesterol) and the amount of hydroperoxides. No significant difference is observed between n-3 PUFA levels during processing and at different storage conditions. The order of oxidative stability, as calculated by the hydroperoxides determination was: grated bottarga < whole bottarga < raw roe. 相似文献