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41.
Vincenzo Penteriani Anna Kuparinen Maria del Mar Delgado Francisco Palomares José Vicente López-Bao José María Fedriani Javier Calzada Sacramento Moreno Rafael Villafuerte Letizia Campioni Rui Lourenço 《Oecologia》2013,173(3):753-766
We compared movement patterns and rhythms of activity of a top predator, the Iberian lynx Lynx pardinus, a mesopredator, the red fox Vulpes vulpes, and their shared principal prey, the rabbit Oryctolagus cuniculus, in relation to moon phases. Because the three species are mostly nocturnal and crepuscular, we hypothesized that the shared prey would reduce its activity at most risky moon phases (i.e. during the brightest nights), but that fox, an intraguild prey of lynx, would avoid lynx activity peaks at the same time. Rabbits generally moved further from their core areas on darkest nights (i.e. new moon), using direct movements which minimize predation risk. Though rabbits responded to the increased predation risk by reducing their activity during the full moon, this response may require several days, and the moon effect we observed on the rabbits had, therefore, a temporal gap. Lynx activity patterns may be at least partially mirroring rabbit activity: around new moons, when rabbits moved furthest and were more active, lynxes reduced their travelling distances and their movements were concentrated in the core areas of their home ranges, which generally correspond to areas of high density of rabbits. Red foxes were more active during the darkest nights, when both the conditions for rabbit hunting were the best and lynxes moved less. On the one hand, foxes increased their activity when rabbits were further from their core areas and moved with more discrete displacements; on the other hand, fox activity in relation to the moon seemed to reduce dangerous encounters with its intraguild predator. 相似文献
42.
Stanley C. Lorbach Jessup M. Shively Vincenzo Buonfiglio 《Geomicrobiology journal》2013,30(3-4):219-226
Abstract Thiobacillus ferrooxidans ATCC 23270 was grown with elemental sulfur as the energy source. Substrate oxidation was measured using a Clark‐type oxygen electrode. Whole cells demonstrated a broad pH optimum for sulfur oxidation between pH 2.0 and 8.0. The V max and Ksfor sulfur oxidation varied depending on pH. Sulfite was oxidized at 227 nmol O2/min/mg protein. Thiosulfate oxidation was slow, and tetrathionate oxidation was not detected. At a concentration of 2 mM, sodium azide completely inhibited sulfur, sulfite, and thiosulfate oxidation. Inhibition by N‐ethylmaleimide, antimycin A, and 2‐heptyl‐4‐hydroxyquinoline N‐oxide varied with substrate. 相似文献
43.
44.
Atilla Akdemir Daniela Vullo Viviana De Luca Andrea Scozzafava Vincenzo Carginale Mosè Rossi Claudiu T. Supuran Clemente Capasso 《Bioorganic & medicinal chemistry letters》2013,23(4):1087-1090
The α-carbonic anhydrase (CA, EC 4.2.1.1) from the extremophilic bacterium Sulfurihydrogenibium azorense (SazCA) was recently shown to be the fastest CA known. Here we investigated this enzyme for its activation with a series of amino acids and amines. The best SazCA activators were d-Phe, l-DOPA, l- and d-Trp, dopamine and serotonin, which showed activation constants in the range of 3–23 nM. l- and d-His, l-Phe, l-Tyr, 2-pyridyl-methylamine and L-adrenaline were also effective activators (KAs in the range of 62–90 nM), whereas d-Dopa, d-Tyr and several heterocyclic amines showed activity in the micromolar range. The good thermal stability, robustness, very high catalytic activity and propensity to be activated by simple amino acids and amines, make SazCA a very interesting candidate for biomimetic CO2 capture processes. 相似文献
45.
Sonia Del Prete Daniela Vullo Viviana De Luca Vincenzo Carginale Andrea Scozzafava Claudiu T. Supuran Clemente Capasso 《Bioorganic & medicinal chemistry letters》2013,23(14):4067-4071
Carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the γ-class are present in archaea, bacteria and plants but, except the Methanosarcina thermophila enzymes CAM and CAMH, they were poorly characterized so far. Here we report a new such enzyme (PgiCA), the γ-CA from the oral cavity pathogenic bacterium Porphyromonas gingivalis, the main causative agent of periodontitis. PgiCA showed a good catalytic activity for the CO2 hydration reaction, comparable to that of the human (h) isoform hCA I. Inorganic anions such as thiocyanate, cyanide, azide, hydrogen sulfide, sulfamate and trithiocarbonate were effective PgiCA inhibitors with inhibition constants in the range of 41–97 μM. Other effective inhibitors were diethyldithiocarbamate, sulfamide, and phenylboronic acid, with KIs of 4.0–9.8 μM. The role of this enzyme as a possible virulence factor of P. gingivalis is poorly understood at the moment but its good catalytic activity and the possibility to be inhibited by a large number of compounds may lead to interesting developments in the field. 相似文献
46.
Aytül Hamzalıoğlu Burçe A. Mogol Roberta Barone Lumaga Vincenzo Fogliano Vural Gökmen 《Amino acids》2013,44(6):1419-1426
This study aimed to investigate the ability of curcumin to convert asparagine into acrylamide during heating at different temperatures. Binary and ternary model systems of asparagine–curcumin and asparagine–curcumin–fructose were used to determine the role of curcumin on acrylamide formation in competitive and uncompetitive reaction conditions. The results indicated that curcumin could potentially contribute to acrylamide formation under long-term heating conditions as long as asparagine was present in the medium. The amount of acrylamide formed in the ternary system was slightly higher than in the binary system during heating (p < 0.05), because of the higher concentrations of carbonyl compounds initially available. The kinetic trends were similar in both model systems evidencing that fructose reacted with asparagine more rapidly than curcumin. The data reveal that acrylamide formation in the temperature range of 150–200°C obeys Arrhenius law with activation energy of 79.1 kJ/mole. Data of this work showed the possibility that antioxidants having a carbonyl compound can react directly with ASN leading to acrylamide. The addition of antioxidants to foods may increase the formation of acrylamide upon long-term heating if free sugar concentration is low and ASN concentration is relatively high. 相似文献
47.
Vincenzo Verdoliva Cinzia Senatore Maria Letizia Polci Stefania Rossi Martina Cordella Giuseppe Carlucci Paolo Marchetti Giancarlo Antonini-Cappellini Antonio Facchiano Daniela D'Arcangelo Francesco Facchiano 《PloS one》2013,8(3)
Recently developed proteomic technologies allow to profile thousands of proteins within a high-throughput approach towards biomarker discovery, although results are not as satisfactory as expected. In the present study we demonstrate that serum proteome denaturation is a key underestimated feature; in fact, a new differential denaturation protocol better discriminates serum proteins according to their electrophoretic mobility as compared to single-denaturation protocols. Sixty nine different denaturation treatments were tested and the 3 most discriminating ones were selected (TRIDENT analysis) and applied to human sera, showing a significant improvement of serum protein discrimination as confirmed by MALDI-TOF/MS and LC-MS/MS identification, depending on the type of denaturation applied. Thereafter sera from mice and patients carrying cutaneous melanoma were analyzed through TRIDENT. Nine and 8 protein bands were found differentially expressed in mice and human melanoma sera, compared to healthy controls (p<0.05); three of them were found, for the first time, significantly modulated: α2macroglobulin (down-regulated in melanoma, p<0.001), Apolipoprotein-E and Apolipoprotein-A1 (both up-regulated in melanoma, p<0.04), both in mice and humans. The modulation was confirmed by immunological methods. Other less abundant proteins (e.g. gelsolin) were found significantly modulated (p<0.05).Conclusions: i) serum proteome contains a large amount of information, still neglected, related to proteins folding; ii) a careful serum denaturation may significantly improve analytical procedures involving complex protein mixtures; iii) serum differential denaturation protocol highlights interesting proteomic differences between cancer and healthy sera. 相似文献
48.
Ilya G. Kichigin Massimo Giovannotti Alex I. Makunin Bee L. Ng Marsel R. Kabilov Alexey E. Tupikin Vincenzo Caputo Barucchi Andrea Splendiani Paolo Ruggeri Willem Rens Patricia C. M. O’Brien Malcolm A. Ferguson-Smith Alexander S. Graphodatsky Vladimir A. Trifonov 《Molecular genetics and genomics : MGG》2016,291(5):1955-1966
49.
Vincenzo De Cicco Massimo Barresi Maria Paola Tramonti Fantozzi Enrico Cataldo Vincenzo Parisi Diego Manzoni 《PloS one》2016,11(2)
Several studies have demonstrated that chewing can be regarded as a preventive measure for cognitive impairment, whereas masticatory deficiency, associated with soft-diet feeding, is a risk factor for the development of dementia. At present the link between orofacial sensorimotor activity and cognitive functions is unknown. In subjects with unilateral molar loss we have shown asymmetries in both pupil size and masticatory muscles electromyographic (EMG) activity during clenching: the molar less side was characterized by a lower EMG activity and a smaller pupil. Since implant-prostheses, greatly reduced both the asymmetry in EMG activity and in pupil’s size, trigeminal unbalance, leading to unbalance in the activity of the Locus Coeruleus (LC), may be responsible for the pupil’s asymmetry. According to the findings obtained in animal models, we propose that the different activity of the right and left LC may induce an asymmetry in brain activity, thus leading to cognitive impairment. According to this hypothesis, prostheses improved the performance in a complex sensorimotor task and increased the mydriasis associated with haptic tasks. In conclusion, the present study indicates that the implant-prosthesis therapy, which reduces the unbalance of trigeminal proprioceptive afferents and the asymmetry in pupil’s size, may improve arousal, boosting performance in a complex sensorimotor task. 相似文献