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排序方式: 共有3216条查询结果,搜索用时 15 毫秒
41.
Chaima Ragoubi Laura Quintieri Donato Greco Amel Mehrez Imed Maatouk Vito DAscanio Ahmed Landoulsi Giuseppina Avantaggiato 《Toxins》2021,13(3)
The removal of mycotoxins from contaminated feed using lactic acid bacteria (LAB) has been proposed as an inexpensive, safe, and promising mycotoxin decontamination strategy. In this study, viable and heat-inactivated L. acidophilus CIP 76.13T and L. delbrueckii subsp. bulgaricus CIP 101027T cells were investigated for their ability to remove aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEA), and deoxynivalenol (DON) from MRS medium and PBS buffer over a 24 h period at 37 °C. LAB decontamination activity was also assessed in a ZEA-contaminated liquid feed (LF). Residual mycotoxin concentrations were determined by UHPLC-FLD/DAD analysis. In PBS, viable L. acidophilus CIP 76.13T and L. delbrueckii subsp. bulgaricus CIP 101027T cells removed up to 57% and 30% of ZEA and DON, respectively, while AFB1 and OTA reductions were lower than 15%. In MRS, 28% and 33% of ZEA and AFB1 were removed, respectively; OTA and DON reductions were small (≤15%). Regardless of the medium, heat-inactivated cells produced significantly lower mycotoxin reductions than those obtained with viable cells. An adsorption mechanism was suggested to explain the reductions in AFB1 and OTA, while biodegradation could be responsible for the removal of ZEA and DON. Both viable LAB strains reduced ZEA by 23% in contaminated LF after 48 h of incubation. These findings suggest that LAB strains of L. acidophilus CIP 76.13T and L. delbrueckii subsp. bulgaricus CIP 101027T may be applied in the feed industry to reduce mycotoxin contamination. 相似文献
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Lo Casto Antonio Cannella Roberto Taravella Rossana Cordova Adriana Matta Daniele Campisi Giuseppina Attanasio Massimo Rinaldi Gaetana Rodolico Vito 《La Radiologia medica》2022,127(12):1364-1372
La radiologia medica - To evaluate the accuracy of preoperative contrast-enhanced magnetic resonance imaging (MRI) in the assessment of radiological depth of invasion (rDOI) and bone invasion in... 相似文献
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Cancer cells undergo genetic changes allowing their adaptation to environmental changes, thereby obtaining an advantage during the long metastatic route, disseminated of several changes in the surrounding environment. In particular, plasticity in cell motility, mainly due to epigenetic regulation of cancer cells by environmental insults, engage adaptive strategies aimed essentially to survive in hostile milieu, thereby escaping adverse sites. This review is focused on tumor microenvironment as a collection of structural and cellular elements promoting plasticity and adaptive programs. We analyze the role of extracellular matrix stiffness, hypoxia, nutrient deprivation, acidity, as well as different cell populations of tumor microenvironment. 相似文献
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Advanced glycation end products and vascular inflammation: implications for accelerated atherosclerosis in diabetes 总被引:31,自引:0,他引:31
The formation of advanced glycation end products (AGEs) is an important biochemical abnormality that accompanies diabetes mellitus and, likely, inflammation in general. Here we summarize and discuss recent studies indicating that the effects of AGEs on vessel wall homeostasis may account for the rapidly progressive atherosclerosis associated with diabetes mellitus. Driven by hyperglycemia and oxidant stress, AGEs form to a greatly accelerated degree in diabetes. Within the vessel wall, collagen-linked AGEs may "trap" plasma proteins, quench nitric oxide (NO) activity and interact with specific receptors to modulate a large number of cellular properties. On plasma low density lipoproteins (LDL), AGEs initiate oxidative reactions that promote the formation of oxidized LDL. Interaction of AGEs with endothelial cells as well as with other cells accumulating within the atherosclerotic plaque, such as mononuclear phagocytes and smooth muscle cells (SMCs), provides a mechanism to augment vascular dysfunction. Specifically, the interaction of AGEs with vessel wall components increases vascular permeability, the expression of procoagulant activity and the generation of reactive oxygen species (ROS), resulting in increased endothelial expression of endothelial leukocyte adhesion molecules. AGEs potently modulate initiating steps in atherogenesis involving blood-vessel wall interactions, triggering an inflammatory-proliferative process and, furthermore, critically contribute to propagation of inflammation and vascular perturbation in established disease. Thus, a better understanding of the biochemical mechanisms by which AGEs contribute to such processes in the vessel wall could be relevant to devise preventive and therapeutic strategies for diabetic atherosclerosis. 相似文献
48.
Predictors of cognitive improvement after reality orientation in Alzheimer's disease 总被引:1,自引:0,他引:1
Zanetti O Oriani M Geroldi C Binetti G Frisoni GB Di Giovanni G De Vreese LP 《Age and ageing》2002,31(3):193-196
BACKGROUND: there is increasing evidence to support the efficacy of reality orientation in cognitive deficits in patients with Alzheimer's disease. The clinical characteristics of patients who respond to reality orientation are poorly understood; this knowledge could be important, given that the provision of reality orientation therapy is labour-intensive and may provoke emotional distress. AIM: to evaluate retrospectively which demographic and clinical characteristics of Alzheimer's patients predict cognitive outcomes. METHOD: we analysed 38 mild-to-moderately demented outpatients who regularly attended a one-month formal reality orientation programme. The mini mental state examination score changes from baseline-and immediately after-reality orientation were correlated with demographic and pre-treatment clinical characteristics by a linear regression analysis. RESULTS: short-term responsiveness to reality orientation was significantly predicted by a lower level of cognitive functioning (as measured by the mini mental state examination) at baseline and by the absence of euphoria, accounting together for 57.6% of variance. CONCLUSION: a lower mini mental state examination and the absence of euphoric behaviour in patients with mild-to-moderate Alzheimer's disease may predict a good cognitive outcome of reality orientation therapy. 相似文献
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Fazio G Mongiovi' M Sutera L Novo G Novo S Pipitone S 《International journal of cardiology》2008,123(2):e31-e34
Wolff-Parkinson-White (WPW) is a syndrome characterized by the presence of an accessory pathway that skipping A-V node may lead the electrical stimulus from the atrium directly to the ventricle. Some studies reported the finding of myocardial dyskinesia in the segments precociously activated by the accessory pathway, at echocardiogram and at nuclear cardiac study. Soria et al. reported, in 1985, an increased incidence of dilative cardiomyopathy in patients with WPW. The pathophysiological pathway that leads to ventricular dilation may be due to the increase of end-diastolic pressure secondary to a tachycardia-induced cardiomyopathy. Tachycardia-induced cardiomyopathy is usually secondary to frequent and prolonged tachycardia episodes. In this paper we report the cases of three patients affected by WPW who developed dilative cardiomyopathy during the follow-up. Particularly dyskinetic segments, working such as a functional aneurysm, could induce deep modifications of intraventricular haemodynamics, leading to remodelling and progressive ventricular dilation. This hypothesis could have important empirical consequences because it could imply the necessity of a precocious ablative therapy in this kind of patients. 相似文献