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421.
Federica Del Chierico Daniela Gnani Pamela Vernocchi Andrea Petrucca Anna Alisi Bruno Dallapiccola Valerio Nobili Putignani Lorenza 《International journal of molecular sciences》2014,15(1):684-711
Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide as a result of the increasing prevalence of obesity, starting from early life stages. It is characterized by a spectrum of liver diseases ranging from simple fatty liver (NAFL) to steatohepatitis (NASH), with a possible progression to fibrosis, thus increasing liver-related morbidity and mortality. NAFLD development is driven by the co-action of several risk factors, including obesity and metabolic syndrome, which may be both genetically induced and diet-related. Recently, particular attention has been paid to the gut-liver axis, which may play a physio-pathological role in the onset and progression of the disease. The gut microbiota is intended to act as a bioreactor that can guarantee autonomous metabolic and immunological functions and that can drive functional strategies within the environment of the body in response to external stimuli. The complexity of the gut microbiota suggests that it behaves as an organ. Therefore, the concept of the gut-liver axis must be complemented with the gut-microbiota-liver network due to the high intricacy of the microbiota components and metabolic activities; these activities form the active diet-driven power plant of the host. Such complexity can only be revealed using systems biology, which can integrate clinical phenomics and gut microbiota data. 相似文献
422.
Rameshwar Adhikari Netra Lal Bhandari Valerio Causin Hai H. Le Hans‐Joachim Radusch Goerg H. Michler Jean Marc Saiter 《Polymer Engineering and Science》2012,52(11):2296-2303
Aiming at development of completely biodegradable composite materials based on locally available low‐cost bamboo flour (BF) as filler, structure properties correlations in aliphatic–aromatic copolyester/BF composites fabricated by melt mixing have been studied by means of different techniques such as electron microscopy, X‐ray diffraction, tensile testing, and thermogravimetric analysis (TGA). It has been demonstrated that the BF can be successfully incorporated homogeneously into the biodegradable polymeric matrix up to high content. The filler weakly adheres to the matrix as demonstrated by the pulling up of bamboo fibers on the electron micrographs and further attested by TGA. At high filler concentration, the polymer acts merely as binding material. The semicrystalline framework of the matrix polymer is hindered by the presence of the fibers, the structural changes being more pronounced at the surfaces than in the bulk, which indicates preferential segregation of the fibers toward the specimen surface. This opens new possibilities for a more detailed engineering of materials surfaces. The mechanical properties of the composites are suited for low‐load‐bearing applications. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers 相似文献
423.
The structure and aggregation state of amyloid beta-peptide (Abeta) in membrane-like environments are important determinants of pathological events in Alzheimer's disease. In fact, the neurotoxic nature of amyloid-forming peptides and proteins is associated with specific conformational transitions proximal to the membrane. Under certain conditions, the Abeta peptide undergoes a conformational change that brings the peptide in solution to a "competent state" for aggregation. Conversion can be obtained at medium pH (5.0-6.0), and in vivo this appears to take place in the endocytic pathway. The combined use of (1)H NMR spectroscopy and molecular dynamics-simulated annealing calculations in aqueous hexafluoroisopropanol simulating the membrane environment, at different pH conditions, enabled us to get some insights into the aggregation process of Abeta, confirming our previous hypotheses of a relationship between conformational flexibility and aggregation propensity. The conformational space of the peptide was explored by means of an innovative use of principal component analysis as applied to residue-by-residue root-mean-square deviations values from a reference structure. This procedure allowed us to identify the aggregation-prone regions of the peptide. 相似文献
424.
The effect of murta (Ugni molinae Turcz) leaves extract on water vapor permeability (WVP) and gas permeability (GP) of carboxymethylcellulose (CMC)-based films was studied. Two ecotypes of murta leaves “Soloyo Grande” (SG) and “Soloyo Chico” (SC), were analyzed for their composition (HPLC-MS) and SC extract revealed a higher concentration of flavonols than the SG extract. The film forming solution was prepared with 2 g of CMC, 0.4 ml of glycerol and 0.5 ml of sunflower oil in 100 ml of water (Control), 50 ml of water and 50 ml of each exctract (SC50 or SG50) and 100 ml of each extract (SC 100 or SG 100). The addition of murta leaves extract modified the WVP and GP of the films. The WVP decreased significantly (P?0.05) with the incorporation of SG extract in the film but not with the SC extract (P>0.05). The CO2 and O2 permeability of the films were influenced by the kind and concentration of murta leaves extract used. The CO2 permeability, with SG extract was higher than without extract (P?0.05) and with SC extract was not modified. The O2 permeability with murta leaves extract were lower than without extract. Therefore, it is possible to consider that films with SC acts only as barrier to the oxygen, but with SG the water vapor and gas barrier properties were modified, being more permeable to the CO2 and acting as barrier to O2 and water vapor. 相似文献
425.
Functional verification techniques based on fault injection and simulation at register-transfer level (RTL) have been largely investigated in the past years. Although they have various advantages such as scalability and simplicity, they commonly suffer from the low speed of the cycle-accurate RTL simulation. On the other hand, Transaction-level modeling (TLM) allows a simulation speed sensibly faster than RTL. This article presents FAST, a framework to accelerate RTL fault simulation through automatic RTL-to-TLM abstraction. FAST abstracts RTL models injected with any RTL fault model into equivalent injected TLM models thus allowing a very fast fault simulation at TLM level. The article also presents FAST-DT, a new bit-accurate data type library integrated in the framework that allows a further improvement of the simulation speed-up. Finally, the article shows how the generated TLM test patterns can be automatically synthesized into RTL test patterns by exploiting the structural information of the RTL model extracted during the abstraction process. Experimental results have been performed on several designs of different size and complexity to show the methodology effectiveness. 相似文献
426.
The metabolic syndrome develops in an individual with any three of the following risk factors: obesity, diabetes, inflammation, hypertension, dyslipidemia, and thrombosis. Recent evidence suggests that vitamin D may play a role in the development of some of these risk factors. The metabolic syndrome is more common in western societies than the underdeveloped countries. Individuals in western societies usually consume a high calorie diet that lacks essential nutrients and, by virtue of being located in the northern hemisphere, they have limited sun exposures which restrict their vitamin D synthesis. Moreover, the lifestyle of these societies is considered sedentary. These dietary and environmental factors coupled with the sedentary lifestyle predispose them to metabolic syndrome risk factors. Active research revealed the role of vitamin D in the development of obesity, diabetes, inflammation, and hypertension. On the other hand, limited research has been done on the role of vitamin D in other risk factors such as dyslipidemia and thrombosis. The scientific community proposes to increase the current vitamin D fortification level in foods to reduce the risk factors of the metabolic syndrome. 相似文献
427.
Marco Pilotti Giulia Valerio Claudia Giardino Mariano Bresciani Steven C. Chapra 《Journal of Great Lakes research》2018,44(1):14-25
During an initial field survey in 2012, we observed an unexpected asymmetry of dissolved oxygen distribution between the western and eastern side in northern Lake Iseo. Motivated by this apparent anomaly, we conducted a detailed field investigation, and we used a physical model of the northern part of the lake to understand the influences that might affect the distribution of material in the northern section of the lake. These investigations suggested that the Earth's rotation has significant influence on the inflow of the lake's two main tributaries. In order to further crosscheck the validity of these results, we conducted a careful analysis at a synoptic scale using images acquired during thermally unstratified periods by Landsat-8 and Sentinel-2 satellites. We retrieved and post-processed a large set of images, providing conclusive evidence of the role exerted by the Earth's rotation on pollutant transport in Lake Iseo and of the greater environmental vulnerability of the north-west shore of this lake, where important settlements are located. Our study confirms the necessity for three-dimensional hydrodynamic models including Coriolis effect in order to effectively predict local impacts of inflows on nearshore water quality of medium-sized elongated lakes of similar scale to Lake Iseo. 相似文献
428.
Serena Federico Francesca Glaviano Roberta Esposito Bruno Pinto Maissa Gharbi Anna Di Cosmo Maria Costantini Valerio Zupo 《International journal of molecular sciences》2022,23(21)
The increase in the demand for Paracentrotus lividus roe, a food delicacy, causes increased pressure on its wild stocks. In this scenario, aquaculture facilities will mitigate the effects of anthropogenic pressures on the wild stocks of P. lividus. Consequently, experimental studies should be conducted to enhance techniques to improve efficient aquaculture practices for these animals. Here, we for the first time performed molecular investigations on cultured sea urchins. We aimed at understanding if maternal influences may significantly impact the life of future offspring, and how the culture conditions may impact the development and growth of cultured specimens. Our findings demonstrate that the outcomes of in vitro fertilization of P. lividus are influenced by maternal influences, but these effects are largely determined by culture conditions. In fact, twenty-three genes involved in the response to stress and skeletogenesis, whose expressions were measured by Real Time qPCR, were differently expressed in sea urchins cultured in two experimental conditions, and the results were largely modified in offspring deriving from two groups of females. The findings herein reported will be critical to develop protocols for the larval culture of the most common sea urchin, both for research and industrial production purposes for mass production. 相似文献
429.
Denise Drongitis Lucia Verrillo Pasqualino De Marinis Pasquale Orabona Agnese Caiola Giacinto Turitto Alessandra Alfieri Sara Bruscella Marisa Gentile Vania Moriello Ettore Sannino Ines Di Muccio Valerio Costa Maria Giuseppina Miano Alberto de Bellis 《International journal of molecular sciences》2022,23(18)
430.
Federica Del Chierico Giorgia Conta Maria Cristina Matteoli Alessandra Fierabracci Sofia Reddel Gabriele Macari Simone Gardini Valerio Guarrasi Stefano Levi Mortera Valeria Marzano Pamela Vernocchi Fabio Sciubba Federico Marini Annalisa Deodati Novella Rapini Stefano Cianfarani Alfredo Miccheli Lorenza Putignani 《International journal of molecular sciences》2022,23(18)
Alterations of gut microbiota have been identified before clinical manifestation of type 1 diabetes (T1D). To identify the associations amongst gut microbiome profile, metabolism and disease markers, the 16S rRNA-based microbiota profiling and 1H-NMR metabolomic analysis were performed on stool samples of 52 T1D patients at onset, 17 T1D siblings and 57 healthy subjects (CTRL). Univariate, multivariate analyses and classification models were applied to clinical and -omic integrated datasets. In T1D patients and their siblings, Clostridiales and Dorea were increased and Dialister and Akkermansia were decreased compared to CTRL, while in T1D, Lachnospiraceae were higher and Collinsella was lower, compared to siblings and CTRL. Higher levels of isobutyrate, malonate, Clostridium, Enterobacteriaceae, Clostridiales, Bacteroidales, were associated to T1D compared to CTRL. Patients with higher anti-GAD levels showed low abundances of Roseburia, Faecalibacterium and Alistipes and those with normal blood pH and low serum HbA1c levels showed high levels of purine and pyrimidine intermediates. We detected specific gut microbiota profiles linked to both T1D at the onset and to diabetes familiarity. The presence of specific microbial and metabolic profiles in gut linked to anti-GAD levels and to blood acidosis can be considered as predictive biomarker associated progression and severity of T1D. 相似文献