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排序方式: 共有3427条查询结果,搜索用时 18 毫秒
171.
Alessandro Mantovani Paolo Gisondi Amedeo Lonardo Giovanni Targher 《International journal of molecular sciences》2016,17(2)
Over the past 10 years, it has become increasingly evident that nonalcoholic fatty liver disease (NAFLD) is a multisystem disease that affects multiple extra-hepatic organ systems and interacts with the regulation of several metabolic and immunological pathways. In this review we discuss the rapidly expanding body of clinical and epidemiological evidence supporting a strong association between NAFLD and chronic plaque psoriasis. We also briefly discuss the possible biological mechanisms underlying this association, and discuss treatment options for psoriasis that may influence NAFLD development and progression. Recent observational studies have shown that the prevalence of NAFLD (as diagnosed either by imaging or by histology) is remarkably higher in psoriatic patients (occurring in up to 50% of these patients) than in matched control subjects. Notably, psoriasis is associated with NAFLD even after adjusting for metabolic syndrome traits and other potential confounding factors. Some studies have also suggested that psoriatic patients are more likely to have the more advanced forms of NAFLD than non-psoriatic controls, and that psoriatic patients with NAFLD have more severe psoriasis than those without NAFLD. In conclusion, the published evidence argues for more careful evaluation and surveillance of NAFLD among patients with psoriasis. 相似文献
172.
Francesca Bugli Federica Massaro Francesco Buonocore Paolo Roberto Saraceni Stefano Borocci Francesca Ceccacci Cecilia Bombelli Maura Di Vito Rosalba Marchitiello Melinda Mariotti Riccardo Torelli Maurizio Sanguinetti Fernando Porcelli 《International journal of molecular sciences》2022,23(4)
The increasing resistance of fungi to antibiotics is a severe challenge in public health, and newly effective drugs are required. Promising potential medications are lipopeptides, linear antimicrobial peptides (AMPs) conjugated to a lipid tail, usually at the N-terminus. In this paper, we investigated the in vitro and in vivo antifungal activity of three short myristoylated and non-myristoylated peptides derived from a mutant of the AMP Chionodracine. We determined their interaction with anionic and zwitterionic membrane-mimicking vesicles and their structure during this interaction. We then investigated their cytotoxic and hemolytic activity against mammalian cells. Lipidated peptides showed a broad spectrum of activity against a relevant panel of pathogen fungi belonging to Candida spp., including the multidrug-resistant C. auris. The antifungal activity was also observed vs. biofilms of C. albicans, C. tropicalis, and C. auris. Finally, a pilot efficacy study was conducted on the in vivo model consisting of Galleria mellonella larvae. Treatment with the most-promising myristoylated peptide was effective in counteracting the infection from C. auris and C. albicans and the death of the larvae. Therefore, this myristoylated peptide is a potential candidate to develop antifungal agents against human fungal pathogens. 相似文献
173.
Martina Fabris Fabio Del Ben Emanuela Sozio Antonio Paolo Beltrami Adriana Cif Giacomo Bertolino Federica Caponnetto Marco Cotrufo Carlo Tascini Francesco Curcio 《International journal of molecular sciences》2022,23(9)
The main aim of this study was to identify the most relevant cytokines which, when assessed in the earliest stages from hospital admission, may help to select COVID-19 patients with worse prognosis. A retrospective observational study was conducted in 415 COVID-19 patients (272 males; mean age 68 ± 14 years) hospitalized between May 2020 and March 2021. Within the first 72 h from hospital admission, patients were tested for a large panel of biomarkers, including C-reactive protein (CRP), Mid-regional proadrenomedullin (MR-proADM), Interferon-γ, interleukin 6 (IL-6), IL-1β, IL-8, IL-10, soluble IL2-receptor-α (sIL2Rα), IP10 and TNFα. Extensive statistical analyses were performed (correlations, t-tests, ranking tests and tree modeling). The mortality rate was 65/415 (15.7%) and a negative outcome (death and/or orotracheal intubation) affected 98/415 (23.6%) of cases. Univariate tests showed the majority of biomarkers increased in severe patients, but ranking tests helped to select the best variables to put on decisional tree modeling which identified IL-6 as the first dichotomic marker with a cut-off of 114 pg/mL. Then, a good synergy was found between IL-10, MR-proADM, sIL2Rα, IP10 and CRP in increasing the predictive value in classifying patients at risk or not for a negative outcome. In conclusion, beside IL-6, a panel of other cytokines representing the degree of immunoparalysis and the anti-inflammatory response (IP10, sIL2Rα and IL-10) showed synergic role when combined to biomarkers of systemic inflammation and endothelial dysfunction (CRP, MR-proADM) and may also better explain disease pathogenesis and suggests targeted intervention. 相似文献
174.
Roberta Di Monte Paolo Fornasiero Jan Ka
par Paolo Rumori Giuseppe Gubitosa Mauro Graziani 《Applied catalysis. B, Environmental》2000,24(3-4):157-167
Pd-loaded Ce0.6Zr0.4O2 solid solutions supported on Al2O3 are investigated as catalysts for the reduction of NO by CO. The attention is focused on the role of the Ce0.6Zr0.4O2 and of the Pd dispersion on the catalytic activity. The system shows a very high activity below 500 K, which is almost independent on the Pd dispersion. The high activity is attributed to a promoting effect of the Ce0.6Zr0.4O2 on the NO conversion. Investigation of the influence of high temperature treatments disclosed a thermal stabilisation of both Ce0.6Zr0.4O2 and Al2O3 in the Ce0.6Zr0.4O2/Al2O3 system. 相似文献
175.
Maria Chiara Dalconi Giuseppe Cruciani Alberto Alberti Paolo Ciambelli 《Catalysis Today》2005,110(3-4):345-350
High-silica zeolites exchanged with transition metal ions (TMIs) are the subject of great interest for their unusual catalytic activity and selectivity. Structural information like coordination and accessibility of TMIs in zeolites are important factors for understanding their catalytic activity. Siting of TMIs in zeolites is typically obtained by spectroscopic (EXAFS, EPR, UV–vis and IR) and computational methods, as in the case of Co-ferrierite. However, some controversy exists in the literature concerning the model for incorporation of bare Co ions in ferrierite. We show here that the results of our synchrotron X-ray powder diffraction studies on Co- and Ni-exchanged ferrierite (Si/Al = 8.5) are in a good agreement with the model of Co siting based on an indirect spectroscopic approach and help to validate this model. By direct structural evidences, a possible explanation for the larger catalytic activity of Co sites in the main channels of ferrierite can be inferred. A combination of data from in situ XRD continuous monitoring of the Co ion migration during calcination and crystal-chemical considerations allows to device a strategy for the design of optimised co-cations containing Co-ferrierite catalysts. 相似文献
176.
Roberto Rosa Paolo Veronesi Marco Michelazzi Cristina Leonelli Aldo R. Boccaccini 《Surface & coatings technology》2012
Electrophoretic deposition (EPD) was used to deposit sub-micrometric ZrO2 particles on metallic powder compacts belonging to the systems Ni + Al and Ti + Al, which were used as deposition electrodes in the EPD cell. After EPD, combustion synthesis (CS) of such reactive electrodes was ignited in a microwave single-mode applicator, operating at a frequency of 2.45 GHz, in order to obtain in a single step the synthesis of the desired intermetallic phase (substrate) and the sintering of the previously deposited ceramic particles (or coating). Experimental results demonstrate that the excess heat released during the formation of nickel and titanium aluminides by CS can be exploited not only to self-sustain and self-propagate the reaction front along the substrate, but also to rapidly sinter the coating obtained by EPD. The innovative procedure here proposed is a promising strategy in order to obtain, in a single step, high temperature intermetallic-based materials, protected by well adhered ceramic coatings. 相似文献
177.
Effects of cutting angle,edge preparation,and nano-structured coating on milling performance of a gamma titanium aluminide 总被引:1,自引:0,他引:1
Paolo Claudio Priarone Stefania Rizzuti Luca Settineri Guido Vergnano 《Journal of Materials Processing Technology》2012,212(12):2619-2628
Gamma titanium aluminides are intermetallic alloys. Recently, they have been evaluated as important contenders for structural applications in the automotive and aerospace sectors. This is due to their excellent high-temperature performances and their significantly lower density compared to nickel-based superalloys. In this paper, an analysis of machinability of a gamma TiAl obtained via an electron beam melting (EBM) process is presented. The effects of tool geometry modifications, in terms of cutting tool angles and cutting edge preparation, were investigated. The reduction of radial rake angle and the drag finishing process for cutting edge preparation resulted in an increase of the tool life of the carbide end mills. Nanogradient tool coatings were also observed to affect tool wear during milling tests, and the results highlight that AlSiTiN coating performs better compared to CrAlSiN coating. A post-coating polishing treatment was also taken into account, and it allowed a further reduction of tool wear. The overall results indicate that the machinability of this difficult-to-cut material can be significantly improved by an adjustment of the cutting edge geometry, and by using an AlSiTiN coating system. 相似文献
178.
Carletti P Masi A Spolaore B Polverino De Laureto P De Zorzi M Turetta L Ferretti M Nardi S 《Journal of chemical ecology》2008,34(6):804-818
Humic substances are known to affect plant metabolism at different levels. We characterized humic substances extracted from earthworm feces by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and used them to treat corn, Zea mays L., seedlings to investigate changes in patterns of root protein expression. After root plasma membrane extraction and purification, proteins were separated by two-dimensional gel electrophoresis, and differential spot intensities were evaluated by image analysis. Finally, 42 differentially expressed proteins were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The majority of them were downregulated by the treatment with humic substances. The proteins identified included malate dehydrogenase, ATPases, cytoskeleton proteins, and different enzymes belonging to the glycolytic/gluconeogenic pathways and sucrose metabolism. The identification of factors involved in plant responses to humic substances may improve our understanding of plant-soil cross-talk, and enable a better management of soil resources. 相似文献
179.
180.
Francesco Paolo La Mantia Nadka Tzankova Dintcheva Roberto Scaffaro Rosamaria Marino 《大分子材料与工程》2008,293(1):83-91
The influence of an elongational flow on the morphology of PE/clay nanocomposite drawn fibers was studied. An increase of the elastic modulus and the tensile strength as well as a decrease of the elongation at break are observed with increasing draw ratio. The applied elongational gradient orients the polymer chains and the clay particles along the spinning direction. When the applied flow results in the formation and the orientation of exfoliated nanoparticles, a pronounced increase of the mechanical properties is observed. The dispersed clay particles can be broken and oriented by the extensional flow, which might indicate a flow‐induced intercalated/exfoliated morphology transition.