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71.
Mauro Vigan Nicola Pugliese Federica Cerini Federica Turati Vincenzo Cimino Sofia Ridolfo Simone Rocchetto Francesca Foglio Maria Terrin Carlo La Vecchia Maria Grazia Rumi Alessio Aghemo 《International journal of molecular sciences》2022,23(20)
The identification of advanced fibrosis by applying noninvasive tests is still a key component of the diagnostic algorithm of NAFLD. The aim of this study is to assess the concordance between the FIB-4 and liver stiffness measurement (LSM) in patients referred to two liver centers for the ultrasound-based diagnosis of NAFLD. Fibrosis 4 Index for Liver Fibrosis (FIB-4) and LSM were assessed in 1338 patients. A total of 428 (32%) had an LSM ≥ 8 kPa, whereas 699 (52%) and 113 (9%) patients had an FIB-4 < 1.3 and >3.25, respectively. Among 699 patients with an FIB-4 < 1.3, 118 (17%) had an LSM ≥ 8 kPa (false-negative FIB-4). This proportion was higher in patients ≥60 years, with diabetes mellitus (DM), arterial hypertension or a body mass index (BMI) ≥ 27 kg/m2. In multiple adjusted models, age ≥ 60 years (odds ratio (OR) = 1.96, 95% confidence interval (CI) 1.19–3.23)), DM (OR = 2.59, 95% CI 1.63–4.13), body mass index (BMI) ≥ 27 kg/m2 (OR = 2.17, 95% CI 1.33–3.56) and gamma-glutamyltransferase ≥ 25 UI/L (OR = 2.68, 95% CI 1.49–4.84) were associated with false-negative FIB-4. The proportion of false-negative FIB-4 was 6% in patients with none or one of these risk factors and increased to 16, 31 and 46% among those with two, three and four concomitant risk factors, respectively. FIB-4 is suboptimal to identify patients to refer to liver centers, because about one-fifth may be false negative at FIB-4, having instead an LSM ≥ 8 KPa. 相似文献
72.
An LC-ESI-MS/MS method was developed for the quantitative detection of postharvest fungicide residues in citrus juices and reported in this paper. The analyses of thiabendazole (TBZ), carbendazim (MBC), thiophanate methyl (TPM), imazalil (IMZ) and prochloraz (PCZ) residues were performed by using a gradient elution in conjunction with positive ionization mode electrospray ionization tandem mass spectrometry. Fungicides were extracted from citrus juices with recoveries ranging from 79.8 to 101.2% and relative standard deviation better than 15%. The quantification limits ranged from 0.01 μg/kg IMZ to 0.06 μg/kg for MBC. The LC-MS-MS method was applied to commercial citrus juices, detecting MBC, TBZ and IMZ residues in the 90% of the samples. Prochloraz residues were detected only in one of the multifruit juice (orange, lemon and carrot) samples. 相似文献
73.
Latorre L Parisi A Fraccalvieri R Normanno G La Porta MC Goffredo E Palazzo L Ciccarese G Addante N Santagada G 《Journal of food protection》2007,70(6):1507-1512
Listeria monocytogenes is an important foodborne pathogen that causes gastrointestinal disorders, and, especially in immunocompromised people, serious extraintestinal diseases, such as septicemia and meningitis, as well as abortion in pregnant women. Many foods, from both plant and animal origin, have been involved in listeriosis outbreaks. This article reports the results of a 12-year survey (1993 through 2004) on the presence of L. monocytogenes in several kinds of food marketed in Italy. Of 5,788 analyzed samples, 121 (2.1%) were contaminated with L. monocytogenes. The highest prevalence was found in smoked salmon (10.6%) and in poultry meat samples (8.5%) and the lowest in red meat (0.3%). L. monocytogenes was not found in 154 samples of fresh seafood products. Fifty-two isolates were also serotyped by the agglutination method. The most common serotypes detected in the 52 strains tested were 1/2a (36.5%), followed by 1/2c (32.8%), 1/2b (13.5%), 4b (11.5%), 3a (3.8%), and 3b (1.9%). The results of the present study showed low levels of L. monocytogenes in the analyzed samples. A total of 61.5% of the 52 L. monocytogenes strains analyzed belonged to serotypes 1/2a, 1/2b, and 4b, namely the serovars that are most commonly involved in extraintestinal human listeriosis outbreaks. In the ready-to-eat samples, these three serotypes were 40.0% (1/2a), 17.1% (1/2b), and 14.3% (4b). This finding highlights the need to implement strict hygienic measures during the production, distribution, and sale of foods to reduce the risk of foodborne listeriosis in humans to an acceptable level. 相似文献
74.
Angel Cobos María I. Cambero Juan A Ordez Lorenzo De La Hoz 《Journal of the science of food and agriculture》1993,62(1):83-88
The effects of beef tallow-, soya and sunflower olein- and soya bean oil-enriched (3%) diets on the chemical and fatty acid composition of total, a polar and polar lipids of rabbit meat have been studied. No significant differences (P > 0.05) in the meat chemical composition were observed between groups. However, a large effect of the diet on the total and apolar lipid fatty acids was found, with C18:1 and C18:2 the most affected fatty acids. The influence of the diets on the fatty acids of the polar fraction was less marked. It is concluded that the enrichment of the rabbit diet with either soya and sunflower oleins or soya bean oil allows the production of rabbit meat with a higher unsaturation degree than is obtained by using conventional diets, which constitutes an important nutritional benefit to the human being. 相似文献
75.
A. Baiano G. Gambacorta C. Terracone M.A. Previtali C. Lamacchia E. La Notte 《Journal of food science》2009,74(2):C177-C183
ABSTRACT: Phenolic composition and antioxidant activity of extra‐virgin olive oils extracted from several Italian varieties were studied at production and during storage. The antioxidant activity was measured according to the following tests: in the aqueous phase, by radical scavenging of the 2,2′‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS) radical cation; and in the lipid phase, using the β‐carotene bleaching method. The phenolic content was not correlated to the oxidation indices (peroxide value and spectrophotometric constants). The phenolic contents and profiles of the various cultivars showed remarkable differences. The phenolic content was strongly correlated with the antioxidant activity measured according to the β‐carotene test and weakly correlated with the radical scavenging ability. 相似文献
76.
77.
In this work we report the properties of nanocomposite based on PET with two different samples of organically modified montmorillonites. In particular, we studied the effect of the filler concentration on morphology, rheology, and mechanical performance, focusing our attention on the effect of the degradation phenomena of the clay modifiers. The results indicate that at low clay level the morphology achieved is mainly intercalated. On increasing the filler level, coalescence and/or bad defragmentation phenomena induce a coarser morphology, as confirmed by XRD, SEM, and TEM observations. When a more polar organic modifier is used to modify the clay, the particle adhesion and distribution is slightly better. Conversely, at the processing temperatures adopted, this organic modifier induces a strong degradation of PET, as confirmed by melt rheology and intrinsic viscosity measurements. DSC indicates, in addition, a slight increase of crystallinity likely due to the decreased molecular weight. As regards the mechanical properties, Young's modulus is not significantly changed unless high amounts of clay (10%) are used while the elongation at break drops even at the lowest clay content. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
78.
Influence of sepiolite nanoclay on the properties of the resulting join between poly(lactic acid) (PLA) and different Polyamide66 (PA66)/nanoclay nanocomposites was studied in this work. Six different polymer nanocomposites based on PA66 were manufactured through a melt compounding process by adding a fixed 1.64 wt % of a commercial IR absorber additive and the respective weight percentages of sepiolite to the polymer matrix. Several nanocomposite/PLA joints were finally performed by means of the transmission laser welding technology and the resulting weldings were characterized in terms of mechanical properties by performing peeling and shearing tests. Furthermore, both welded and mechanically tested samples were also analyzed by scanning electron microscopy in order to study the morphology of the weld seam. The results of the performed tests show that the addition of sepiolite to the PA66 improves the welding performance only in those cases in which the percentage of sepiolite of the nanocomposites is higher than 5 wt %. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46638. 相似文献
79.
本文介绍用有限元方法对盘绕蛇形高压贮气罐(以下简称贮气罐)进行优化设计.计算与测试结果表明,其外径与内径之比K值的设计小于国外同类产品的k值. 相似文献
80.
Synthetic and Biological Studies of Sesquiterpene Polygodial: Activity of 9‐Epipolygodial against Drug‐Resistant Cancer Cells 下载免费PDF全文
Dr. Ramesh Dasari Annelise De Carvalho Derek C. Medellin Kelsey N. Middleton Dr. Frédéric Hague Marie N. M. Volmar Prof. Liliya V. Frolova Dr. Mateus F. Rossato Jorge J. De La Chapa Nicholas F. Dybdal‐Hargreaves Akshita Pillai Prof. Véronique Mathieu Prof. Snezna Rogelj Prof. Cara B. Gonzales Prof. João B. Calixto Prof. Antonio Evidente Dr. Mathieu Gautier Dr. Gnanasekar Munirathinam Prof. Rainer Glass Prof. Patricia Burth Dr. Stephen C. Pelly Prof. Willem A. L. van Otterlo Prof. Robert Kiss Prof. Alexander Kornienko 《ChemMedChem》2015,10(12):2014-2026
Polygodial, a terpenoid dialdehyde isolated from Polygonum hydropiper L., is a known agonist of the transient receptor potential vanilloid 1 (TRPV1). In this investigation a series of polygodial analogues were prepared and investigated for TRPV1‐agonist and anticancer activities. These experiments led to the identification of 9‐epipolygodial, which has antiproliferative potency significantly exceeding that of polygodial. 9‐Epipolygodial was found to maintain potency against apoptosis‐resistant cancer cells as well as those displaying the multidrug‐resistant (MDR) phenotype. In addition, the chemical feasibility for the previously proposed mechanism of action of polygodial, involving the formation of a Paal–Knorr pyrrole with a lysine residue on the target protein, was demonstrated by the synthesis of a stable polygodial pyrrole derivative. These studies reveal rich chemical and biological properties associated with polygodial and its direct derivatives. These compounds should inspire further work in this area aimed at the development of new pharmacological agents, or the exploration of novel mechanisms of covalent modification of biological molecules with natural products. 相似文献