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411.
The occurrence of the fumonisins B(1) and B(2) in maize-based food products marketed in Italy was examined. A simply and reliable chromatographic method with fluorimetric detection and postcolumn o-phtalaldehyde derivatization was used for a monitoring of 100 samples (8 flours, 21 corn-meal, 16 snacks, 7 maize samples, 13 gluten-free products, and 35 corn-flakes) bought in local supermarkets during the years 2008 and 2009. The presence of both fumonisins B(1) and B(2), at a concentration higher than 15 μg/kg, was observed in all samples of corn-meal and maize-flour, in 75% of snacks, in 57% of maize samples, in 54% of gluten-free products, and in 29% of corn-flakes. A total of 7 samples including 4 corn-meals, 2 maize-flours, and 1 maize showed a value exceeding the maximum level fixed in the Regulation 1126/2007/EC; no positive sample was observed in corn-flakes, snacks, and gluten-free foods. Fumonisins contamination, on the whole range of maize-based food products analyzed, emphasizes the need of improve agricultural practices, and increase official control and monitoring studies. 相似文献
412.
High Saturated Fat Diet Alters the Lipid Composition of Triacylglycerol and Polar Lipids in the Femur of Dam and Offspring Rats
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Paula M. Miotto Laura M. Castelli Foyinsola Amoye Wendy E. Ward Paul J. LeBlanc 《Lipids》2015,50(6):605-610
Previous work has shown that dietary lipids alter femur lipid composition. Specifically, we have shown that exposure to high saturated fatty acid (SFA) diets in utero, during suckling, or post‐weaning alters femur total lipid composition, resulting in higher percent bone mass in males and females and bone mineral density (BMD) in female offspring with no effect on bone mineral outcomes in dams. Comparatively, high n‐3 polyunsaturated fatty acid (PUFA) diets increase femur polar (PL) lipid n‐3 content, which has been associated with increased bone mineral content and strength. However, the extent that PL or triacylglycerol (TAG) lipids change with high SFA diets is unknown. The current investigation examined the influence of a high SFA diet (20 % lard by weight) on femur PL and TAG lipid composition in 5‐month old female Wistar rats (fed high SFA diet from age 28 days onwards; dams) and their 19‐day old offspring (exposed to high SFA in utero and during suckling; pups). High SFA exposure resulted in increased monounsaturates and decreased n‐3 and n‐6 PUFA in the TAG fraction in both dams and pups, and higher SFA and n‐6:n‐3 ratio in dams only. The PL fraction showed decreased n‐6 PUFA in both dams and pups. The magnitude of the diet‐mediated responses, specifically TAG 18:1 and PL n‐6 PUFA, may have contributed to the previously reported altered BMD, which was supported with correlation analysis. Future research should investigate the relationship of diet‐induced changes in bone lipids on bone structure, as quantified through micro‐computed tomography. 相似文献
413.
Elena Azzini Ilaria Peluso Federica Intorre Lorenzo Barnaba Eugenia Venneria Maria Stella Foddai Donatella Ciarapica Francesca Maiani Anna Raguzzini Angela Polito 《International journal of molecular sciences》2022,23(14)
Background: Inflammatory cytokine levels are associated with Non-Communicable Diseases (NCDs) and can be influenced by a person’s macronutrient profile. This work aims to evaluate the relationship between the compliance with the age-specific recommended protein intake and the levels of inflammatory markers related to the risk of NCDs. Methods: The study participants included 347 participants (119 men and 228 women), ages 18 to 86 years. Cardio-metabolic risk evaluations, including an assessment of the prevalence of Metabolic Syndrome, were performed. Leptin, IL-15, IL-6, and TNF-α levels were measured. Results: The adequacy of the total protein (TP) intake was lower in old people compared to individuals aged <60 years, and only few volunteers consumed the suggested 50% plant protein (PP) for a healthy and sustainable diet. A lower risk of NCDs with a PP consumption above at least 40% was observed only in old individuals. A differential effect on TNF-α and IL-6 was observed for both TP and PP intake by gender and age class, whereas for leptin and IL-15 only significant interactions among sex and the class of age were found. Conclusion: Although our data suggest that consuming more than 40% of PP can reduce the risk of NCDs, the effect of gender differences on cytokine levels should be considered in larger studies. 相似文献
414.
Isothermal cyclic deformation tests were conducted on HASTELLOY X with a total strain range of ±0.3 pct at several temperatures
and strain rates. Cyclic hardening exhibited a broad peak between about 200 °C and 700 °C, with a maximum near 500 °C of about
80 pct increase in stress amplitude, Δσ/2, at failure. The present work examines the mechanisms contributing to this marked
cyclic hardening. Cr23C6 precipitation on dislocations contributed to hardening, but only with sufficient time above about 500 °C. The substantial
hardening rate at lower temperatures or shorter times was attributed to solute drag. The contribution of solute drag was evidenced
in tests at both 400 °C and 600 °C by a continually decreasing strain rate sensitivity of the AcrJ2. Solute drag alone produced
very considerable cyclic hardening. The increase in AcrJ2 after 1000 cycles at 427 °C was 75 pct of the maximum observed at
higher temperatures where carbides did precipitate. Additionally, thermomechanical tests were conducted between various temperature
limits, but with the same ±0.3 pct mechanical strain range. Hardening was bounded by isothermal behavior at the temperature
limits of the thermomechanical cycles, except for tests between 400 °C and 600 °C which exhibited extreme hardening. However,
microstructural examination did not suggest a cause. Specimens subjected to thermomechanical cycles appeared similar to those
isothermally cycled at the maximum temperature of the thermomechanical cycle, including those from the 400 °C to 600 °C tests. 相似文献
415.
Donatella Carbonera Alessandro Agostini Marco Bortolus Luca DallOsto Roberto Bassi 《International journal of molecular sciences》2022,23(9)
Carotenoids represent the first line of defence of photosystems against singlet oxygen (1O2) toxicity, because of their capacity to quench the chlorophyll triplet state (3Chl) through a physical mechanism based on the transfer of triplet excitation (triplet–triplet energy transfer, TTET). In previous works, we showed that the antenna LHCII is characterised by a robust photoprotective mechanism, able to adapt to the removal of individual chlorophylls while maintaining a remarkable capacity for 3Chl quenching. In this work, we investigated the effects on this quenching induced in LHCII by the replacement of the lutein bound at the L1 site with violaxanthin and zeaxanthin. We studied LHCII isolated from the Arabidopsis thaliana mutants lut2—in which lutein is replaced by violaxanthin—and lut2 npq2, in which all xanthophylls are replaced constitutively by zeaxanthin. We characterised the photophysics of these systems via optically detected magnetic resonance (ODMR) and time-resolved electron paramagnetic resonance (TR-EPR). We concluded that, in LHCII, lutein-binding sites have conserved characteristics, and ensure efficient TTET regardless of the identity of the carotenoid accommodated. 相似文献
416.
Donatella Sterpi 《Canadian Metallurgical Quarterly》2003,3(1):111-122
The gradual erosion and transport of fine particles are among the possible consequences to the subsoil of a severe seepage flow, such as the seepage induced by the artificial lowering of the water table by means of pumping wells. The erosion, in turn, could induce local effects, in terms of reductions in the soil volume and variations in the soil mechanical characteristics, that could be non-negligible when working in an urban area. In this paper, some laboratory tests are presented aimed at investigating the erosion of fine particles from soil samples subjected to a controlled seepage flow. The phenomenon of erosion and transport is then modeled by combining, in a single governing equation, the conservation of mass of moving particles with a suitable law of erosion, which is calibrated on the basis of the seepage tests. This equation, coupled with the equation governing the seepage problem, permits one to evaluate the quantity of particles eroded and transported from the soil mass. The effects of the loss of fine material on the stress–strain distribution within the soil mass are estimated by a finite-element analysis. The proposed model is then adopted for the evaluation of the surface settlements induced by the water pumping from a drainage trench. 相似文献
417.
Ilaria Bestetti Milena Crippa Alessandra Sironi Francesca Tumiatti Maura Masciadri Marie Falkenberg Smeland Swati Naik Oliver Murch Maria Teresa Bonati Alice Spano Elisa Cattaneo Milena Mariani Fabio Gotta Francesca Crosti Pietro Cavalli Chiara Pantaleoni Federica Natacci Maria Francesca Bedeschi Donatella Milani Silvia Maitz Angelo Selicorni Luigina Spaccini Angela Peron Silvia Russo Lidia Larizza Karen Low Palma Finelli 《International journal of molecular sciences》2022,23(11)
KBG syndrome (KBGS) is a neurodevelopmental disorder caused by the Ankyrin Repeat Domain 11 (ANKRD11) haploinsufficiency. Here, we report the molecular investigations performed on a cohort of 33 individuals with KBGS clinical suspicion. By using a multi-testing genomic approach, including gene sequencing, Chromosome Microarray Analysis (CMA), and RT-qPCR gene expression assay, we searched for pathogenic alterations in ANKRD11. A molecular diagnosis was obtained in 22 out of 33 patients (67%). ANKRD11 sequencing disclosed pathogenic or likely pathogenic variants in 18 out of 33 patients. CMA identified one full and one terminal ANKRD11 pathogenic deletions, and one partial duplication and one intronic microdeletion, with both possibly being pathogenic. The pathogenic effect was established by RT-qPCR, which confirmed ANKRD11 haploinsufficiency only for the three deletions. Moreover, RT-qPCR applied to six molecularly unsolved KBGS patients identified gene downregulation in a clinically typical patient with previous negative tests, and further molecular investigations revealed a cryptic deletion involving the gene promoter. In conclusion, ANKRD11 pathogenic variants could also involve the regulatory regions of the gene. Moreover, the application of a multi-test approach along with the innovative use of RT-qPCR improved the diagnostic yield in KBGS suspected patients. 相似文献
418.
Alice Verdelli Marzia Caproni Alessio Coi Alberto Corr Donatella DeglInnocenti Marzia Vasarri Lavinia Quintarelli Valter Volpi Emanuele Maria Cipollini Emanuela Barletta 《International journal of molecular sciences》2022,23(20)
Background: Studies have demonstrated a higher risk of nonmelanoma skin cancers (NMSC) and a modestly increased melanoma risk in patients with psoriasis. To date, no biomarkers predictive of evolution have been identified yet. Methods: The aim of this prospective case-control study was to investigate the potential role of neutrophil gelatinase-associated lipocalin (NGAL) as a predictive biomarker of skin cancers in psoriatic patients. Patients with a diagnosis of psoriasis were enrolled, as well as healthy subjects and patients with skin cancers as controls. Plasma protein expression of NGAL, metalloproteinases (MMP)-2, and MMP-9 was performed by an enzyme-linked immunosorbent assay (ELISA). In all the patients who developed skin cancer at follow-up, NGAL, MMP-2, and MMP-9 serum levels were dosed again. Results: Plasma NGAL levels were significantly higher in psoriatic patients with NMSC than without (182.3 ± 36.6 ng/mL vs. 139.9 ± 39.3 ng/mL) (p < 0.001). Plasma NGAL levels were significantly higher (p < 0.00001) in patients with psoriasis and NMSC than in patients with skin tumors without psoriasis (182.3 vs. 122.9). Patients with psoriasis who developed NMSC at follow-up showed increased plasma MMP-9 levels. Conclusion: NGAL seems to play a role in the pathogenesis of NMSC but not melanoma in patients with psoriasis. 相似文献
419.
Claudia De Vitis Michela DAscanio Andrea Sacconi Dario Pizzirusso Valentina Salvati Massimiliano Mancini Giorgia Scafetta Roberto Cirombella Francesca Ascenzi Sara Bruschini Antonella Esposito Silvia Castelli Claudia Salvucci Leonardo Teodonio Bruno Sposato Angela Catizone Arianna Di Napoli Andrea Vecchione Gennaro Ciliberto Salvatore Sciacchitano Alberto Ricci Rita Mancini 《International journal of molecular sciences》2022,23(23)
Idiopathic pulmonary fibrosis (IPF) is a disease characterized by progressive scarring of the lung that involves the pulmonary interstitium. The disease may rapidly progress, leading to respiratory failure, and the long-term survival is poor. There are no accurate biomarkers available so far. Our aim was to evaluate the expression of the B4GALT1 in patients with IPF. Analysis of B4GALT1 gene expression was performed in silico on two gene sets, retrieved from the Gene Expression Omnibus database. Expression of B4GALT1 was then evaluated, both at the mRNA and protein levels, on lung specimens obtained from lung biopsies of 4 IPF patients, on one IPF-derived human primary cell and on 11 cases of IPF associated with cancer. In silico re-analysis demonstrated that the B4GALT1 gene was overexpressed in patients and human cell cultures with IPF (p = 0.03). Network analysis demonstrated that B4GALT1 upregulation was correlated with genes belonging to the EMT pathway (p = 0.01). The overexpression of B4GALT1 was observed, both at mRNA and protein levels, in lung biopsies of our four IPF patients and in the IPF-derived human primary cell, in other fibrotic non-lung tissues, and in IPF associated with cancer. In conclusion, our results indicate that B4GALT1 is overexpressed in IPF and could represent a novel marker of this disease. 相似文献
420.
Mathematical modeling of eggplant drying: Shrinkage effect 总被引:1,自引:0,他引:1
Antonio Brasiello Giuseppina Adiletta Paola Russo Silvestro Crescitelli Donatella Albanese Marisa Di Matteo 《Journal of food engineering》2013
In this paper two mathematical models with shrinkage effect describing eggplant drying are developed and discussed. The models are both modified diffusion equations and take differently into account changes of eggplant slice structure during drying. In the first model a diffusion coefficient variable with the water content is considered while in the second model a fictitious convective term is introduced. The two models are both suitable to describe the analyzed drying processes. Moreover, their equivalence is analytically demonstrated. Parameters values are estimated through a nonlinear regression procedure by comparison with the drying experiments carried out at different temperatures. Information about thickness evolution, derived from the models, are found to be in agreement with experimental data. 相似文献