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61.
Sabrina Sicolo Maurizio Bruschi Luca Bertini Giuseppe Zampella Giulia Filippi Federica Arrigoni Luca De Gioia Claudio Greco 《International Journal of Hydrogen Energy》2014
[FeFe]-hydrogenases are the most efficient biological catalysts available for the H2 evolution reaction. Their active site – the H-cluster – features a diiron subsite which has the peculiar characteristic of bearing cyanide groups hydrogen-bonded to the apoprotein as well as carbonyl ligands. Notably, one of the CO ligands is disposed in bridging position between the metal centers. This allows one of the Fe ions to retain a square pyramidal coordination – which determines the assumption of the so-called “rotated structure” – with a vacant coordination site in trans to the μ-CO group, ready to bind protons when the active site is in the FeIFeI state. Many FeIFeI biomimetic models have been synthesized and characterized so far, but most of them fail to reproduce the orientation of the diatomic ligands that is observed in the enzyme active site. 相似文献
62.
Graziamaria Corbi Andrea Bianco Viviana Turchiarelli Michele Cellurale Federica Fatica Aurora Daniele Gennaro Mazzarella Nicola Ferrara 《International journal of molecular sciences》2013,14(6):12696-12713
The development of atherosclerosis is a multi-step process, at least in part controlled by the vascular endothelium function. Observations in humans and experimental models of atherosclerosis have identified monocyte recruitment as an early event in atherogenesis. Chronic inflammation is associated with ageing and its related diseases (e.g., atherosclerosis and chronic obstructive pulmonary disease). Recently it has been discovered that Sirtuins (NAD+-dependent deacetylases) represent a pivotal regulator of longevity and health. They appear to have a prominent role in vascular biology and regulate aspects of age-dependent atherosclerosis. Many studies demonstrate that SIRT1 exhibits anti-inflammatory properties in vitro (e.g., fatty acid-induced inflammation), in vivo (e.g., atherosclerosis, sustainment of normal immune function in knock-out mice) and in clinical studies (e.g., patients with chronic obstructive pulmonary disease). Because of a significant reduction of SIRT1 in rodent lungs exposed to cigarette smoke and in lungs of patients with chronic obstructive pulmonary disease (COPD), activation of SIRT1 may be a potential target for chronic obstructive pulmonary disease therapy. We review the inflammatory mechanisms involved in COPD-CVD coexistence and the potential role of SIRT1 in the regulation of these systems. 相似文献
63.
Mina Martini Iolanda Altomonte Rossana Pesi Maria Grazia Tozzi Federica Salari 《International Dairy Journal》2013,28(1):36-39
A trial was carried out on seven Massese ewes, from which individual milk samples were taken during lactation. All the enzyme activities investigated (oxidase activity of xanthine oxidoreductase, gamma-glutamyltranspeptidase, alkaline phosphatase and 5′-nucleotidase) were affected by the lactation phase, with the exception of the dehydrogenase activity of xanthine oxidoreductase (XOR). A higher oxidase activity (XO) of XOR was found when the diameter of milk fat globules was smaller. In addition, the absence of XO in colostrum led to the hypothesis that its antibacterial role is independent of its activity. The increase in alkaline phosphatase activity during lactation requires further research to better define the criteria for pasteurised sheep milk. 相似文献
64.
Fabrizio Quadrini Loredana Santo Vincenzo Tagliaferri Federica Trovalusci 《Polymer Engineering and Science》2010,50(11):2079-2084
A new molding technique is proposed to directly mold small parts from thermoplastic pellets. A small molding machine was designed and fabricated: the mold consisted of a transparent glass and a metallic frame; an infrared (IR) lamp provided the heat for the pellet melting. Molding tests were carried out by using three commercial thermoplastics and two metallic molds. Molding time and IR lamp power were changed to extract a moldability window for each combination of material and metallic mold. In the best process conditions, a high quality of the samples was obtained in terms of mold filling and surface aesthetics. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers 相似文献
65.
Federica Benvenuti Carlo Carlini Mario Marchionna Renata Patrini Anna Maria Raspolli Galletti Glauco Sbrana 《Journal of Inorganic and Organometallic Polymers》1997,7(3):183-201
The synthesis and structural characterization of a novel bidentate ligand such as bis(diphenylphosphino) methane bound to a cross-linked styrene/divinylbenzene resin and to linear poly(styrene) are reported. Moreover, the anchoring of palladium acetate to the above polymeric ligands is described and the structure of the heterogenized palladium(II) complexes obtained is proposed. 相似文献
66.
Toward the Development of Dual‐Targeted Glyceraldehyde‐3‐phosphate Dehydrogenase/Trypanothione Reductase Inhibitors against Trypanosoma brucei and Trypanosoma cruzi
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Prof. Dr. Federica Belluti Elisa Uliassi Giacomo Veronesi Dr. Christian Bergamini Dr. Marcel Kaiser Prof. Dr. Reto Brun Angelo Viola Prof. Dr. Romana Fato Prof. Dr. Paul A. M. Michels Prof. Dr. R. Luise Krauth‐Siegel Prof. Dr. Andrea Cavalli Prof. Dr. Maria Laura Bolognesi 《ChemMedChem》2014,9(2):371-382
A significant improvement in the treatment of trypanosomiases has been achieved with the recent development of nifurtimox–eflornithine combination therapy (NECT). As an alternative to drug combinations and as a means to overcome most of the antitrypanosomatid drug discovery challenges, a multitarget drug design strategy has been envisaged. To begin testing this hypothesis, we designed and developed a series of quinone–coumarin hybrids against glyceraldehyde‐3‐phosphate dehydrogenase/trypanothione reductase (GAPDH/TR). These enzymes belong to metabolic pathways that are vital to Trypanosoma brucei and Trypanosoma cruzi, and have thus been considered promising drug targets. The synthesized molecules were characterized for their dual‐target antitrypanosomal profile, both in enzyme assays and in in vitro parasite cultures. The merged derivative 2‐{[3‐(3‐dimethylaminopropoxy)‐2‐oxo‐2H‐chromen‐7‐yl]oxy}anthracene‐1,4‐dione ( 10 ) showed an IC50 value of 5.4 μM against TbGAPDH and a concomitant Ki value of 2.32 μM against TcTR. Notably, 2‐{4‐[6‐(2‐dimethylaminoethoxy)‐2‐oxo‐2H‐chromen‐3‐yl]phenoxy}anthracene‐1,4‐dione (compound 6 ) displayed a remarkable EC50 value for T. brucei parasites (0.026 μM ) combined with a very low cytotoxicity toward mammalian L6 cells (7.95 μM ). This promising low toxicity of compound 6 might be at least partially due to the fact that it does not interfere with human glutathione reductase. 相似文献
67.
68.
Elizaveta Kon Giuseppe Filardo Francesco Perdisa Alessandro Di Martino Maurizio Busacca Federica Balboni Andrea Sessa Maurilio Marcacci 《Journal of materials science. Materials in medicine》2014,25(10):2437-2444
The increasing interest in the role of subchondral bone with regard to articular surface disease led to the development of new bioengineered strategies. Aim of this study is to evaluate the clinical and MRI outcome after the implantation of a nanostructured biomimetic three-phasic collagen–hydroxyapatite construct for the treatment of chondral and osteochondral defects of the knee in a large cohort of patients. Seventy-nine patients (63 M, 16 W), affected by grade III–IV femoral condyle or trochlea chondral lesions or osteochondritis dissecans (OCD) were consecutively treated. Mean age was 31.0 ± 11.3 years, mean lesion size was 3.2 ± 2.0 cm2. Fifty patients underwent previous surgeries, concurrent procedures were necessary in 39 cases. The clinical outcome was evaluated using the IKDC and Tegner scores at 12 and 24 months of follow-up. At follow-up times an MRI was performed and evaluated with the MOCART score. All the scores improved significantly from the baseline. IKDC subjective score showed a further increase between 12 and 24 months of follow-up, and 82.2 % of the patients improved their symptoms at the final evaluation. Patients affected by OCDs had better results than those with degenerative lesions. Some abnormal MRI findings were present, even though no correlation was found with the clinical outcome. This one-step biomimetic approach developed to favor osteochondral tissue regeneration is effective in treating knees affected by damages of the articular surface, leading to a significant clinical improvement. However, abnormal MRI findings were present, even if not correlated with the clinical outcome. 相似文献
69.
Giorgina Barbara Piccoli Gabriella Guzzo Federica Neve Vigotti Irene Capizzi Roberta Clari Stefania Scognamiglio Valentina Consiglio Emiliano Aroasio Silvana Gonella Andrea Veltri Paolo Avagnina 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(3):590-595
Renal function recovery (RFR), defined as the discontinuation of dialysis after 3 months of replacement therapy, is reported in about 1% of chronic dialysis patients. The role of personalized, intensive dialysis schedules and of resuming low‐protein diets has not been studied to date. This report describes three patients with RFR who were recently treated at a new dialysis unit set up to offer intensive hemodialysis. All three patients were females, aged 73, 75, and 78 years. Kidney disease included vascular‐cholesterol emboli, diabetic nephropathy and vascular and dysmetabolic disease. At time of RFR, the patients had been dialysis‐dependent from 3 months to 1 year. Dialysis was started with different schedules and was progressively discontinued with a “decremental” policy, progressively decreasing number and duration of the sessions. A moderately restricted low‐protein diet (proteins 0.6 g/kg/day) was started immediately after dialysis discontinuation. The most recent update showed that two patients are well off dialysis for 5 and 6 months; the diabetic patient died (sudden death) 3 months after dialysis discontinuation. Within the limits of small numbers, our case series may suggest a role for personalized dialysis treatments and for including low‐protein diets in the therapy, in enhancing long‐term RFR in elderly dialysis patients. 相似文献
70.
Pasini F Verardo V Cerretani L Caboni MF D'Antuono LF 《Journal of the science of food and agriculture》2011,91(15):2858-2864
BACKGROUND: Salad crops of the Brassicaceae family, such as Diplotaxis tenuifolia and Eruca vesicaria, commonly referred to as ‘rocket salads’, have attracted considerable interest as culinary vegetables because of their strong flavour and their content of putative health‐promoting compounds. Among such compounds, glucosinolates and phenolics are well‐known phytochemicals with an important role also in determining the characteristic flavour of these species. In this study, to identify potentially high‐value rocket salads, 37 cultivated types were examined for sensory characters and their relations with glucosinolate and phenolic contents, which ranged from 0.76 to 3.03 g kg?1 dry weight (DW) and from 4.68 to 31.39 g kg?1 DW, respectively. RESULTS: The perception of bitter taste was significantly affected by specific glucosinolates, namely progoitrin/epiprogoitrin and dimeric glucosativin. Aroma intensity was negatively related to glucoalyssin content, whereas pungency was significantly related to total glucosinolate content. Kaempferol‐3‐(2‐sinapoyl‐glucoside)‐4′‐glucoside was positively and significantly related to all flavour trait perceptions. Aroma intensity, pungency, crunchiness and juiciness were positively related to typical rocket salad flavour perception through a prominent direct effect. CONCLUSION: Aroma intensity, pungency, crunchiness and juiciness were strong determinants of overall rocket salad flavour perception. Visual traits also characterised sensory components. Bitterness, usually considered a negative flavour trait, was moderately perceived in the examined material, without negatively affecting typical flavour perception. In the range of the examined material, glucosinolate content did not contrast with typical flavour, demonstrating that good taste and putative health‐promoting properties may coexist. Copyright © 2011 Society of Chemical Industry 相似文献