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排序方式: 共有278条查询结果,搜索用时 31 毫秒
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Melania Melis Mariano Mastinu Stefano Pintus Tiziana Cabras Roberto Crnjar Iole Tomassini Barbarossa 《Molecules (Basel, Switzerland)》2021,26(8)
Taste plays an important role in processes such as food choices, nutrition status and health. Salivary proteins contribute to taste sensitivity. Taste reduction has been associated with obesity. Gender influences the obesity predisposition and the genetic ability to perceive the bitterness of 6-n-propylthiouracil (PROP), oral marker for food preferences and consumption. We investigated variations in the profile of salivary proteome, analyzed by HPLC-ESI-MS, between sixty-one normal weight subjects (NW) and fifty-seven subjects with obesity (OB), based on gender and PROP sensitivity. Results showed variations of taste-related salivary proteins between NW and OB, which were differently associated with gender and PROP sensitivity. High levels of Ps-1, II-2 and IB-1 proteins belonging to basic proline rich proteins (bPRPs) and PRP-1 protein belonging to acid proline rich proteins (aPRPs) were found in OB males, who showed a lower body mass index (BMI) than OB females. High levels of Ps-1 protein and Cystatin SN (Cyst SN) were found in OB non-tasters, who had lower BMI than OB super-tasters. These new insights on the role of salivary proteins as a factor driving the specific weight gain of OB females and super-tasters, suggest the use of specific proteins as a strategic tool modifying taste responses related to eating behavior. 相似文献
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Anna Szabó Rolando Pasquariello Pedro F. Costa Radmila Pavlovic Indi Geurs Koen Dewettinck Chris Vervaet Tiziana A. L. Brevini Fulvio Gandolfi Sandra Van Vlierberghe 《Macromolecular bioscience》2023,23(10):2300016
To provide prominent accessibility of fishmeal to the European population, the currently available, time- and cost-extensive feeding trials, which evaluate fish feed, should be replaced. The current paper reports on the development of a novel 3D culture platform, mimicking the microenvironment of the intestinal mucosa in vitro. The key requirements of the model include sufficient permeability for nutrients and medium-size marker molecules (equilibrium within 24 h), suitable mechanical properties (G' < 10 kPa), and close morphological similarity to the intestinal architecture. To enable processability with light-based 3D printing, a gelatin-methacryloyl-aminoethyl-methacrylate-based biomaterial ink is developed and combined with Tween 20 as porogen to ensure sufficient permeability. To assess the permeability properties of the hydrogels, a static diffusion setup is utilized, indicating that the hydrogel constructs are permeable for a medium size marker molecule (FITC-dextran 4 kg mol−1). Moreover, the mechanical evaluation through rheology evidence a physiologically relevant scaffold stiffness (G' = 4.83 ± 0.78 kPa). Digital light processing-based 3D printing of porogen-containing hydrogels results in the creation of constructs exhibiting a physiologically relevant microarchitecture as evidenced through cryo-scanning electron microscopy. Finally, the combination of the scaffolds with a novel rainbow trout (Oncorhynchus mykiss) intestinal epithelial cell line (RTdi-MI) evidence scaffold biocompatibility. 相似文献
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Mechanism of Thyroxine Deiodination by Naphthyl‐Based Iodothyronine Deiodinase Mimics and the Halogen Bonding Role: A DFT Investigation 下载免费PDF全文
Mariagrazia Fortino Prof. Dr. Tiziana Marino Prof. Nino Russo Prof. Dr. Emilia Sicilia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(23):8554-8560
This paper deals with a systematic density functional theory (DFT) study aiming to unravel the mechanism of the thyroxine (T4) conversion into 3,3′,5‐triiodothyronine (rT3) by using different bio‐inspired naphthyl‐based models, which are able to reproduce the catalytic functions of the type‐3 deiodinase ID‐3. Such naphthalenes, having two selenols, two thiols, and a selenol–thiol pair in peri positions, which were previously synthesized and tested in their deiodinase activity, are able to remove iodine selectively from the inner ring of T4 to produce rT3. Calculations were performed including also an imidazole ring that, mimicking the role of the His residue, plays an essential role deprotonating the selenol/thiol moiety. For all the used complexes, the calculated potential energy surfaces show that the reaction proceeds via an intermediate, characterized by the presence of a X?I?C (X=Se, S) halogen bond, whose transformation into a subsequent intermediate in which the C?I bond is definitively cleaved and the incipient X?I bond is formed represents the rate‐determining step of the whole process. The calculated trend in the barrier heights of the corresponding transition states allows us to rationalize the experimentally observed superior deiodinase activity of the naphthyl‐based compound with two selenol groups. The role of the peri interactions between chalcogen atoms appears to be less prominent in determining the deiodination activity. 相似文献
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Julian Hofmann Dr. Tiziana Ginex Dr. Alba Espargaró Matthias Scheiner Sandra Gunesch Marc Aragó Prof. Dr. Christian Stigloher Prof. Dr. Raimon Sabaté Prof. Dr. F. Javier Luque Prof. Dr. Michael Decker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(19):6015-6027
Many (poly-)phenolic natural products, for example, curcumin and taxifolin, have been studied for their activity against specific hallmarks of neurodegeneration, such as amyloid-β 42 (Aβ42) aggregation and neuroinflammation. Due to their drawbacks, arising from poor pharmacokinetics, rapid metabolism, and even instability in aqueous medium, the biological activity of azobenzene compounds carrying a pharmacophoric catechol group, which have been designed as bioisoteres of curcumin has been examined. Molecular simulations reveal the ability of these compounds to form a hydrophobic cluster with Aβ42, which adopts different folds, affecting the propensity to populate fibril-like conformations. Furthermore, the curcumin bioisosteres exceeded the parent compound in activity against Aβ42 aggregation inhibition, glutamate-induced intracellular oxidative stress in HT22 cells, and neuroinflammation in microglial BV-2 cells. The most active compound prevented apoptosis of HT22 cells at a concentration of 2.5 μm (83 % cell survival), whereas curcumin only showed very low protection at 10 μm (21 % cell survival). 相似文献
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Luana Malacaria Giuseppina Anna Corrente Amerigo Beneduci Emilia Furia Tiziana Marino Gloria Mazzone 《Molecules (Basel, Switzerland)》2021,26(9)
This review focuses on the ability of some natural antioxidant molecules (i.e., hydroxycinnamic acids, coumarin-3-carboxylic acid, quercetin, luteolin and curcumin) to form Al(III)- and Fe(III)-complexes with the aim of evaluating the coordination properties from a combined experimental and theoretical point of view. Despite the contributions of previous studies on the chemical properties and biological activity of these metal complexes involving such natural antioxidants, further detailed relationships between the structure and properties are still required. In this context, the investigation on the coordination properties of Al(III) and Fe(III) toward these natural antioxidant molecules might deserve high interest to design water soluble molecule-based metal carriers that can improve the metal’s intake and/or its removal in living organisms. 相似文献
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Tiziana Forleo Alessandro Zappi Dora Melucci Martina Ciriaci Francesco Griffoni Simone Bacchiocchi Melania Siracusa Tamara Tavoloni Arianna Piersanti 《Molecules (Basel, Switzerland)》2021,26(9)
The international seafood trade is based on food safety, quality, sustainability, and traceability. Mussels are bio-accumulative sessile organisms that need regular control to guarantee their safe consumption. However, no well-established and validated methods exist to trace mussel origin, even if several attempts have been made over the years. Recently, an inorganic multi-elemental fingerprint coupled to multivariate statistics has increasingly been applied in food quality control. The mussel shell can be an excellent reservoir of foreign inorganic chemical species, allowing recording long-term environmental changes. The present work investigates the multi-elemental composition of mussel shells, including Al, Cu, Cr, Zn, Mn, Cd, Co, U, Ba, Ni, Pb, Mg, Sr, and Ca, determined by inductively-coupled plasma mass-spectrometry in Mytilus galloprovincialis collected along the Central Adriatic Coast (Marche Region, Italy) at 25 different sampling sites (18 farms and 7 natural banks) located in seven areas. The experimental data, coupled with chemometric approaches (principal components analysis and linear discriminant analysis), were used to create a statistical model able to discriminate samples as a function of their production site. The LDA model is suitable for achieving a correct assignment of >90% of individuals sampled to their respective harvesting locations and for being applied to counteract fraud. 相似文献
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Matched asymptotics are used formally in the linearized Navier–Stokes equations, the so-called Oseen approximation, to derive a nonlinear law for the flow of a single-phase, incompressible Newtonian fluid through a rigid porous medium. A suitable choice of the linear term gives, to order a Forchheimer-type law. 相似文献
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