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81.
Nicoletta P Mangia Marco A Murgia Giovanni Garau Francesco Fancello Pietrino Deiana 《International Journal of Dairy Technology》2013,66(4):543-551
The use of an autochthonous starter culture made up by Streptococcus thermophilus, Lactococcus lactis subsp. lactis, Lactobacillus plantarum and Lactobacillus casei in the production of experimental Pecorino Sardo Dolce PDO resulted in a high presence of presumptive mesophilic lactococci and lactobacilli, ~10 log colony‐forming units (cfu), and in significantly higher amount of total free amino acids and free fatty acids, 195.1 vs 178.9 and 328.6 vs 191.8 mg/100 g of experimental vs control cheese (made using a commercial starter) respectively. The experimental cheese also displayed better sensory properties such as taste and aftertaste. 相似文献
82.
Federica Zaccheria Rinaldo Psaro Nicoletta Ravasio Laura Sordelli Federica Santoro 《Catalysis Letters》2011,141(4):587-591
Abstract
Styrene oxide can be effectively isomerized to phenyl-acetaldehyde (98%) over amorphous silica alumina catalysts under very mild liquid phase conditions. On the other hand, a copper catalyst prepared using a silica zirconia support gave up to 80% yield in the hydrogenation of styrene oxide to 2-phenyl-ethanol. 相似文献83.
84.
85.
Antonio Raffo Irene Baiamonte Nicoletta Nardo Flavio Paoletti 《European Food Research and Technology》2007,225(3-4):395-405
Physical (weight, firmness) and compositional (sugars, organic acids, ascorbic acid, phenolic compounds and carotenoids) changes
of red sweet peppers (Capsicum annuum L.) were monitored during 21 days of cold storage (at 7.5 °C); fruits were stored without packaging, packaged in low density
polyethylene bags, or after hot water dipping (53 °C for 4 min) and packaging. Packaging prevented water loss, and preserved
the firmness of the fresh product. Sugars (fructose and glucose) content was practically constant throughout the whole storage
time, for all treatments. A moderate accumulation of citric acid was observed during storage, but no marked effects of packaging
and hot water dipping on citric and malic acid content. Ascorbic acid content slightly increased in unpackaged and packaged
fruits, but not in treated+packaged peppers. Hydroxycinnamics total content seemed not to be affected by cold storage, packaging
or hot water treatment, whereas glycosylated flavonoids showed somewhat lowered levels during storage, particularly in the
case of unpackaged and packaged+treated fruits. Regarding carotenoids content, the effect of the considered storage conditions
seemed to be much smaller than that due to ripening stage. Provitamin A content showed an increasing trend in unpackaged and
packaged fruits; packaged+treated peppers were characterised by a lower retention of provitamin A and a higher level of capsanthin
and cucurbitaxanthin A with respect to not treated fruits. On the whole, packaging and hot water treatment did not produce
noticeable adverse effects on the majority of the examined compositional quality parameters. 相似文献
86.
Synthesis and Antiplasmodial Activity of Novel Chloroquine Analogues with Bulky Basic Side Chains 下载免费PDF全文
Dr. Bruno Tasso Dr. Federica Novelli Dr. Michele Tonelli Dr. Anna Barteselli Dr. Nicoletta Basilico Dr. Silvia Parapini Prof. Donatella Taramelli Prof. Anna Sparatore Prof. Fabio Sparatore 《ChemMedChem》2015,10(9):1570-1583
Chloroquine is commonly used in the treatment and prevention of malaria, but Plasmodium falciparum, the main species responsible for malaria‐related deaths, has developed resistance against this drug. Twenty‐seven novel chloroquine (CQ) analogues characterized by a side chain terminated with a bulky basic head group, i.e., octahydro‐2H‐quinolizine and 1,2,3,4,5,6‐hexahydro‐1,5‐methano‐8H‐pyrido[1,2‐a][1,5]diazocin‐8‐one, were synthesized and tested for activity against D‐10 (CQ‐susceptible) and W‐2 (CQ‐resistant) strains of P. falciparum. Most compounds were found to be active against both strains with nanomolar or sub‐micromolar IC50 values. Eleven compounds were found to be 2.7‐ to 13.4‐fold more potent than CQ against the W‐2 strain; among them, four cytisine derivatives appear to be of particular interest, as they combine high potency with low cytotoxicity against two human cell lines (HMEC‐1 and HepG2) along with easier synthetic accessibility. Replacement of the 4‐NH group with a sulfur bridge maintained antiplasmodial activity at a lower level, but produced an improvement in the resistance factor. These compounds warrant further investigation as potential drugs for use in the fight against malaria. 相似文献
87.
Rayssa Ferreira Zanatta Maria Ângela Lacerda Rangel Esper Cesar Rogério Pucci Alessandra Bühler Borges Carlos Rocha Gomes Torres 《Journal of Adhesion Science and Technology》2013,27(1):21-30
Purpose: The aim of this study was to evaluate the effects of different zirconia surface treatments on the bond strength of two self-adhesive resinous cements (SARC).Methods: Two hundred and eight cylindrical specimens were obtained from Y-TZP zirconia (half with diameter 3.2 mm and half with 4.8 mm). After sintering and polishing, specimens were divided into four groups (n = 26), according to surface treatment: Control (no treatment); Sandblasting (Al2O3 particles); Rocatec (Al2O3 particles, tribochemical silica coating and silane application); Laser (Nd: YAG laser: 20 Hz, 100 mJ, 0.2 J/cm²). The surface roughness (Ra) was evaluated after the surface treatments, and the groups were divided into two subgroups (n = 13), according to the SARC tested: RelyX U200 and Bifix SE. The 2.2-mm cylinders were bonded to 4.8-mm cylinders and stressed until failure under shear using a universal testing machine. Bond strength and Ra were analyzed using ANOVA, and Tukey’s test (α = 0.05).Results: Surface treatment was significant (p < 0.0001), but cement type (p = 0.73) was not. Related to roughness, significant differences were found for the treatment type (p < 0.0001), with laser being the treatment with higher Ra values.Conclusions: Nd:YAG laser produced a rougher surface and a higher bond strength compared with sandblasting, silicatization, and control groups. 相似文献
88.
Gianni S Calosci N Aelen JM Vuister GW Brunori M Travaglini-Allocatelli C 《Protein engineering, design & selection : PEDS》2005,18(8):389-395
PDZ domains represent a large family of protein-interaction modules associated with a variety of unrelated proteins with different functions. We report a complete characterization of the kinetic folding mechanism of a fluorescent variant of PDZ2 from PTP-BL, investigated under a variety of different experimental conditions. For this purpose, we engineered a fluorescent variant of this protein Y43W (called pseudo-wild-type, pWT43). The results suggest the presence of a high-energy intermediate in the folding of PDZ2, as revealed by a pronounced non-linear dependence of the unfolding rate constant on denaturant concentration. Such an intermediate may or may not be detectable depending on the experimental conditions, giving rise to apparent two-state folding under stabilizing conditions (e.g. in the presence of sodium sulfate). Interestingly, even under these conditions, three-state folding can be restored by selectively destabilizing the native-like rate-limiting barrier by one specific mutation (V44A). Finally, we show that data taken on pWT43 under different experimental conditions (e.g. different pH values from 2.1 to 8.0 or in the presence of a stabilizing salt) and also data on a site-directed conservative mutant can be rationalized in terms of a simple reaction scheme involving a single set of intermediates and transition states. 相似文献
89.
Andrea Pucci 《Israel journal of chemistry》2018,58(8):837-844
A promising path to cost-effective photovoltaic (PV) systems is sunlight concentration. Over classical non-imaging geometrical concentrators, luminescent solar concentrators (LSCs) possess several advantages: low cost and weight, elevated theoretical concentration factors and aptitude to efficiently working with diffuse light without tracking or cooling equipment. Although considerable progress has been made, current LSC-PV systems attain low power conversion efficiencies due to critical processes that hinder their ability to deliver light to PV cells including fluorescence quenching due to dye aggregation. To overcome this issue, fluorophores with aggregation induced emission (AIEgens) have been proposed thanks to their high Stokes shift and quantum yield in the solid state. In this review, the current state of knowledge concerning the preparation of LSCs based on AIEgens is summarized with special reference on the strategy adopted aimed at increasing the absorption bandwidth while maximizing the solar collection. 相似文献
90.
Bianca Papotti Maria Pia Adorni Cinzia Marchi Francesca Zimetti Nicoletta Ronda Giovanni Panighel Maria Giovanna Lupo Antonietta Vilella Daniela Giuliani Nicola Ferri Franco Bernini 《International journal of molecular sciences》2022,23(20)
The Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) involvement in Alzheimer’s disease (AD) is poorly investigated. We evaluated the in vitro PCSK9 modulation of astrocyte cholesterol metabolism and neuronal cholesterol supplying, which is fundamental for neuronal functions. Moreover, we investigated PCSK9 neurotoxic effects. In human astrocytoma cells, PCSK9 reduced cholesterol content (−20%; p < 0.05), with a greater effect in presence of beta amyloid peptide (Aβ) (−37%; p < 0.01). PCSK9 increased cholesterol synthesis and reduced the uptake of apoE-HDL-derived cholesterol (−36%; p < 0.0001), as well as the LDL receptor (LDLR) and the apoE receptor 2 (ApoER2) expression (−66% and −31%, respectively; p < 0.01). PCSK9 did not modulate ABCA1- and ABCG1-cholesterol efflux, ABCA1 levels, or membrane cholesterol. Conversely, ABCA1 expression and activity, as well as membrane cholesterol, were reduced by Aβ (p < 0.05). In human neuronal cells, PCSK9 reduced apoE-HDL-derived cholesterol uptake (−41%; p < 0.001) and LDLR/apoER2 expression (p < 0.05). Reduced cholesterol internalization occurred also in PCSK9-overexpressing neurons exposed to an astrocyte-conditioned medium (−39%; p < 0.001). PCSK9 reduced neuronal cholesterol content overall (−29%; p < 0.05) and increased the Aβ-induced neurotoxicity (p < 0.0001). Our data revealed an interfering effect of PCSK9, in cooperation with Aβ, on brain cholesterol metabolism leading to neuronal cholesterol reduction, a potentially deleterious effect. PCSK9 also exerted a neurotoxic effect, and thus represents a potential pharmacological target in AD. 相似文献