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51.
Alessandro Chiarucci Marco Calderisi Francesca Casini Ilaria Bonini 《Folia Geobotanica》2008,43(1):19-33
The effects of the chemical and physical factors associated with geothermal activity on plant community structure and composition were investigated in one of the largest geothermal fields of central Italy. The study site was located in the geothermal area of Sasso Pisano – Monte Rotondo Marittimo, Southern Tuscany. The percentage cover of all vascular plant, bryophyte and lichen species was estimated within 119 circular plots of 0.25 m2. For each plot the soil pH, soil temperature, slope, aspect, incident radiation, soil nitrogen and carbon contents were also quantified. Two vascular plants, Calluna vulgaris and Agrostis castellana, were found to be the most widespread species tolerating the harshest conditions in terms of low soil pH and high soil temperature. The most widespread cryptogam species was Hypnum cupressiforme. Spatially autoregressive models showed that a proportion of about 41–51% of the variance in species richness of one group of plants (vascular or cryptogamic plants) could be modelled by using three or four uncorrelated environmental factors respectively (soil temperature, soil nitrogen and soil C/N ratio and these three plus incident radiation). For the total number of species (vascular and cryptogamic plants), the variance explained by the same three uncorrelated variables was about 57%. This study evidenced a strong environmental control of community composition and species richness, in a site subjected to extreme soil values of soil pH and temperature. The dominance of vascular over cryptogamic vegetation in this geothermal site can be explained by the combined effects of geothermal stress (low soil pH and high soil temperature) with the summer drought typical of the Mediterranean climate. 相似文献
52.
Antonella Del Corso Pier Giuseppe Vilardo Mario Cappiello Ilaria Cecconi Massimo Dal Monte Daniela Barsacchi Umberto Mura 《Archives of biochemistry and biophysics》2002,397(2):392-398
Glutathione is one of the most relevant antioxidants present in cells. It exerts its scavenging action through the involvement of efficient and ubiquitous enzymes. GSH on the other hand, because of its chemical features, can scavenge reactive oxygen species without the involvement of enzymatic systems. The study deals with the mobilization of GSH pool in a nonenzymatic antioxidant system by other physiological thiols (i.e., cysteine and cysteinyl-glycine), which are far more sensitive than GSH to oxidative conditions. These thiol compounds, in the presence of iron/EDTA, can promote oxygen activation through their oxidation to disulfides. GSH, through trans-thiolation reactions, can regenerate Cys and CysGly, which can then recycle, thus inducing a massive GSH oxidation. In these conditions, making use of bovine lens aldose reductase as a protein model, evidence is given that Cys and CysGly promote specific protein S-thiolation reactions. The possibility that GSH may be recruited in controlling cellular oxygen tension is considered. 相似文献
53.
Francesco Cerritelli Gianfranco Pizzolorusso Cinzia Renzetti Vincenzo Cozzolino Marianna D’Orazio Mariacristina Lupacchini Benedetta Marinelli Alessandro Accorsi Chiara Lucci Jenny Lancellotti Silvia Ballabio Carola Castelli Daniela Molteni Roberto Besana Lucia Tubaldi Francesco Paolo Perri Paola Fusilli Carmine D’Incecco Gina Barlafante 《PloS one》2015,10(5)
BackgroundDespite some preliminary evidence, it is still largely unknown whether osteopathic manipulative treatment improves preterm clinical outcomes.ResultsA total of 695 newborns were randomly assigned to either the study group (n= 352) or the control group (n=343). A statistical significant difference was observed between the two groups for the primary outcome (13.8 and 17.5 days for the study and control group respectively, p<0.001, effect size: 0.31). Multivariate analysis showed a reduction of the length of stay of 3.9 days (95% CI -5.5 to -2.3, p<0.001). Furthermore, there were significant reductions with treatment as compared to usual care in cost (difference between study and control group: 1,586.01€; 95% CI 1,087.18 to 6,277.28; p<0.001) but not in daily weight gain. There were no complications associated to the intervention.ConclusionsOsteopathic treatment reduced significantly the number of days of hospitalization and is cost-effective on a large cohort of preterm infants. 相似文献
54.
Daniele Balducci Ilaria Lazzari Magda Monari Fabio Piccinelli Gianni Porzi 《Amino acids》2010,38(3):829-837
A new and convenient stereocontrolled synthesis of the optically pure (S)-α-methyl,α-amino acids 6(a–d) that exploits the chiral synthon 1,4-N,N-[(S)-1-phenylethyl]-piperazine-2,5-dione (1) is described. The (S)-1-phenylethyl group, bonded to each of the N-atoms of the 2,5-diketopiperazine, acts as a chiral inductor in the first alkylation, while the steric hindrance appears
to be the determining factor of stereocontrol in third and forth alkylation. 相似文献
55.
Federica Ferrigno Ilaria Biancofiore Savina Malancona Simona Ponzi Giacomo Paonessa Rita Graziani Alberto Bresciani Nadia Gennari Annalise Di Marco Marcel Kaiser Vincenzo Summa Steven Harper Jesus M. Ontoria 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3689-3692
The identification of a new series of growth inhibitors of Trypanosoma brucei rhodesiense, causative agent of Human African Trypanosomiasis (HAT), is described. A selection of compounds from our in-house compound collection was screened in vitro against the parasite leading to the identification of compounds with nanomolar inhibition of T. brucei growth. Preliminary SAR on the hit compound led to the identification of compound 34 that shows low nanomolar parasite growth inhibition (T. brucei EC50 5?nM), is not cytotoxic (HeLa CC50?>?25,000?nM) and is selective over other parasites, such as Trypanosoma cruzi and Plasmodium falciparum (T. cruzi EC50 8120?nM, P. falciparum EC50 3624?nM). 相似文献
56.
57.
Roberta?Addis Ilaria?CampesiEmail author Marco?Fois Giampiero?Capobianco Salvatore?Dessole Grazia?Fenu Andrea?Montella Maria?Grazia?Cattaneo Lucia?M?Vicentini Flavia?Franconi 《Biology of sex differences》2014,5(1):18
Background
Human umbilical endothelial cells (HUVECs) are widely used to study the endothelial physiology and pathology that might be involved in sex and gender differences detected at the cardiovascular level. This study evaluated whether HUVECs are sexually dimorphic in their morphological, proliferative and migratory properties and in the gene and protein expression of oestrogen and androgen receptors and nitric oxide synthase 3 (NOS3). Moreover, because autophagy is influenced by sex, its degree was analysed in male and female HUVECs (MHUVECs and FHUVECs).Methods
Umbilical cords from healthy, normal weight male and female neonates born to healthy non-obese and non-smoking women were studied. HUVEC morphology was analysed by electron microscopy, and their function was investigated by proliferation, viability, wound healing and chemotaxis assays. Gene and protein expression for oestrogen and androgen receptors and for NOS3 were evaluated by real-time PCR and Western blotting, respectively, and the expression of the primary molecules involved in autophagy regulation [protein kinase B (Akt), mammalian target of rapamycin (mTOR), beclin-1 and microtubule-associated protein 1 light chain 3 (LC3)] were detected by Western blotting.Results
Cell proliferation, migration NOS3 mRNA and protein expression were significantly higher in FHUVECs than in MHUVECs. Conversely, beclin-1 and the LC3-II/LC3-I ratio were higher in MHUVECs than in FHUVECs, indicating that male cells are more autophagic than female cells. The expression of oestrogen and androgen receptor genes and proteins, the protein expression of Akt and mTOR and cellular size and shape were not influenced by sex. Body weights of male and female neonates were not significantly different, but the weight of male babies positively correlated with the weight of the mother, suggesting that the mother’s weight may exert a different influence on male and female babies.Conclusions
The results indicate that sex differences exist in prenatal life and are parameter-specific, suggesting that HUVECs of both sexes should be used as an in vitro model to increase the quality and the translational value of research. The sex differences observed in HUVECs could be relevant in explaining the diseases of adulthood because endothelial dysfunction has a crucial role in the pathogenesis of cardiovascular diseases, diabetes mellitus, neurodegeneration and immune disease.58.
Ilaria Papi Giuseppina Pardi Silvia Lenzini Lisandro Benedetti Cecchi Francesco Cinelli 《Plant biosystems》2013,147(3-4):549-593
Abstract Benthic marine flora of Tuscan Archipelago has been studied. Several samples were collected along five islands and some rocks. This paper is a compendium of new and already published data, in which 267 species, varieties, forms and stadia of algae and seagrasses are listed: 5 Bangiophyceae, 182 Florideophyceae, 45 Phaeophyceae, 6 Chlorophyceae, 28 Bryopsidophyceae, 1 Angiospermae. 相似文献
59.
Vanessa Castelli Francesco Melani Claudio Ferri Michele d'Angelo Mariano Catanesi Davide Grassi Elisabetta Benedetti Antonio Giordano Annamaria Cimini Giovambattista Desideri 《Journal of cellular biochemistry》2020,121(12):4862-4869
Oxidative stress is considered the common effector of the cascade of degenerative events in many neurological conditions. Thus, in this paper we tested different nutraceuticals in H2O2 in vitro model to understand if could represent an adjuvant treatment for neurological diseases. In this study, nutraceuticals bacopa, lycopene, astaxanthin, and vitamin B12 were used alone or in combination in human neuronal differentiated SH-SY5Y cells upon hydrogen peroxide-induced injury and neuroprotective, neuronal death pathways were analyzed. The nutraceuticals analyzed were able to protect H2O2 cytotoxic effects, through increasing cell viability and proteins involved in neuroprotection pathways and restoring proteins involved in cell death pathways. On this basis, it is possible to propose the use of these compounds as dietary supplement for the prevention or as adjuvant to the only symptomatic treatments so far available for neurodegenerative diseases. 相似文献
60.