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981.
Giulia Benassi Corrado Battisti Luca Luiselli Luigi Boitani 《Wetlands Ecology and Management》2009,17(5):555-564
Density and species-specific thresholds for three strictly reed bed (Phragmites australis)—related bird species (Ixobrychus minutus, Acrocephalus scirpaceus, Acrocephalus arundinaceus), known as area-sensitive and breeding in an archipelago of 16 Mediterranean marshland fragments (Central Italy), were studied with mapping method techniques. No individuals of these species occurred in fragments smaller than 1 ha. Marshland fragments larger than 10 ha hosted all the three study species. We observed a significant increase in mean density between 0–1 and 1–10 ha for Acrocephalus scirpaceus and between 1–10 and >10 ha for Acrocephalus arundinaceus. Habitat heterogeneity of the marshland fragments was directly correlated to their size area. Therefore, area-sensitivity for the reed bed species can be interpreted also as a heterogeneity-sensitivity effect at fragment scale. In Mediterranean landscapes, a suitable marshland for the entire selected set of reed bed area-sensitive species should have a size greater than 10 ha with a patchy mosaic of reed beds, open waters, and other edge features. 相似文献
982.
Angela Casini Gerhard Kelter Chiara Gabbiani Maria Agostina Cinellu Giovanni Minghetti Dolores Fregona Heinz-Herbert Fiebig Luigi Messori 《Journal of biological inorganic chemistry》2009,14(7):1139-1149
Abstract
The antiproliferative properties of a group of 13 structurally diverse gold(III) compounds, including six mononuclear gold(III) complexes, five dinuclear oxo-bridged gold(III) complexes, and two organogold(III) compounds, toward several human tumor cell lines were evaluated in vitro using a systematic screening strategy. Initially all compounds were tested against a panel of 12 human tumor cell lines, and the best performers were tested against a larger 36-cell-line panel. Very pronounced antiproliferative properties were highlighted in most cases, with cytotoxic potencies commonly falling in the low micromolar—and even nanomolar—range. Overall, good-to-excellent tumor selectivity was established for at least seven compounds, making them particularly attractive for further pharmacological evaluation. Compare analysis suggested that the observed antiproliferative effects are caused by a variety of molecular mechanisms, in most cases “DNA-independent,” and completely different from those of platinum drugs. Remarkably, some new biomolecular systems such as histone deacetylase, protein kinase C/staurosporine, mammalian target of rapamycin/rapamycin, and cyclin-dependent kinases were proposed for the first time as likely biochemical targets for the gold(III) species investigated. The results conclusively qualify gold(III) compounds as a promising class of cytotoxic agents, of outstanding interest for cancer treatment, while providing initial insight into their modes of action. 相似文献983.
The treatment effect of two pilot-scale vertical flow constructed wetlands (VFCWs) on municipal wastewaters and their suitability for irrigation reuse were evaluated in a 2-year (2002–2003) experiment. One VFCW was planted with Typha latifolia and the other with Phragmites australis. VFCW efficiency was evaluated in terms of both mass removal and water quality improvement, considering the following parameters: pH, electrical conductivity (ECw), total suspended solids (TSS), chemical oxygen demand (COD) and biochemical oxygen demand (BOD), total nitrogen (TN) and nitrate (NO3?), total phosphorus (TP) and orthophosphate (PO43?), sodium (Na), potassium (K), magnesium (Mg) and calcium (Ca). The accumulation of the elements in the plant organs and VFCW sandy surface layer and their offtake with the macrophyte harvest were also measured.In quantitative terms the established VFCWs showed higher removal efficiencies (>86%) for COD, BOD, N and K, while lower efficiencies (<47%) were observed for Na and Mg. The direct contribution (offtake) of the macrophytes in N, P and K removal processes was particularly high (>65%) due to the massive growth. The results were less favourable in terms of water quality, because the high evapotranspiration losses counteracted the depuration process by concentrating the elements in the outflow water. Higher concentrations were found in outflow than inflow, especially of Na (relative increase of 89%) and Mg (relative increase of 74%). Only parameters with high removal efficiencies fulfilled the Italian guidelines for irrigation reuse whereas parameters with lower efficiencies (e.g., TSS, TP) limited the potential water reuse. Efficient pre-cleaning systems or innovative integrated systems are thus necessary to obtain high removal efficiencies that reduce the effect of ET on water quality. 相似文献
984.
Toshiko Tanaka Paul Scheet Betti Giusti Stefania Bandinelli Maria Grazia Piras Gianluca Usala Sandra Lai Antonella Mulas Anna Maria Corsi Anna Vestrini Francesco Sofi Anna Maria Gori Rosanna Abbate Jack Guralnik Andrew Singleton Goncalo R. Abecasis David Schlessinger Manuela Uda Luigi Ferrucci 《American journal of human genetics》2009,84(5):712
985.
F. Quaglino Y. Zhao P.A. Bianco W. Wei P. Casati G. Durante & R.E. Davis 《The Annals of applied biology》2009,154(2):279-289
Bois noir (BN) is an insect-transmitted grapevine yellows disease caused by phytoplasmas belonging to the stolbur subgroup 16SrXII-A. In Italy, increasing prevalence of stolbur phytoplasma strains in vineyards suggests progressive spread of the disease and potential for heavy impacts on the wine industry. In this study, we investigated the genetic diversity of stolbur phytoplasma strains in BN phytoplasma populations. Nucleotide sequences of 16S rRNA genes from stolbur phytoplasma strains affecting vineyards in the Lombardy region of Italy and stolbur phytoplasma 16S rDNA sequences retrieved from GenBank were subjected to virtual restriction fragment length polymorphism analysis. Calculation of virtual restriction similarity coefficients revealed the presence of new subgroups in group 16SrXII (stolbur phytoplasma group). Representative strains of confirmed new subgroups 16SrXII-F (XII-F) and XII-G and tentative new subgroups XII-A1 through XII-A19, XII-H, XII-I, and XII-J as well as known subgroup XII-A were from grapevines; strains representing three additional tentative new subgroups (XII-K, XII-L and XII-M) were from other plant hosts. Nucleotide sequence alignments identified no less than nine genetically distinct 16S rDNA single nucleotide polymorphism lineages from grapevine, indicating a high degree of genetic heterogeneity within BN phytoplasma populations. The findings open new opportunities for in-depth studies of the distribution of grapevine-associated 16SrXII phytoplasma strains in weeds, insect vector populations and grapevines from vineyards located in different geographic areas. 相似文献
986.
987.
Seung uk Ko Shari M Ling Joshua Winters Luigi Ferrucci 《Journal of biomechanics》2009,42(12):1834-1839
The aim of this cross-sectional study was to delineate age-associated kinematic and kinetic gait patterns of normal walking, and to test the hypothesis that older adults exhibit gait patterns that reduce generative mechanical work expenditures (MWEs). We studied 52 adult Baltimore Longitudinal Study of Aging participants (means age 72±9, from 60 to 92 years) who could walk 4 m unaided. Three-dimensional kinematic and kinetic parameters assessed during rotation-defined gait periods were used to estimate MWEs for the rotation of lower extremities about the medial–lateral (ML) and anterior–posterior (AP) axes of proximal joints, which represent MWEs in the AP and ML sides, respectively. Relationships between gait parameters and age were examined using regression analysis with adjustments for walking speed, sex, height, and weight. Older age was associated with slower self-selected walking speed (p<0.001), shorter stride length (p<0.001), and greater propensity of landing flat-footed (p=0.003). With older age, hip generative MWE for thigh rotation was lower about the AP axis (hip abduction and adduction) during stance (p=0.010) and higher about the ML axis (hip extension and flexion) during late stance (p<0.001). Knee absorptive MWE for shank rotation about the AP axis (knee abduction and adduction) during early stance was also lower with older age (p<0.003). These age-related gait patterns may represent a compensatory effort to maintain balance and may also reflect mobility limitations. 相似文献
988.
Luigi Sanità di Toppi Antonella Castagna Emanuele Andreozzi Maria Careri Giovanni Predieri Emanuela Vurro Annamaria Ranieri 《Environmental and Experimental Botany》2009,66(2):220-229
Two bread wheat (Triticum aestivum L.) cultivars (Albimonte, traditional cultivar very important in Italy since long time; and Manital, more recent, evincing better productive performances) were grown for 10 d in presence of 0.7 (control), 70 or 350 μM ZnSO4, to verify whether Zn excess was differently managed at inter-varietal and at inter-organ level. Roots were found to be the main site of Zn accumulation, although a moderate metal translocation to leaves occurred in both cultivars. Despite only slight differences in internal Zn concentrations between cultivars, Albimonte seemed to be more sensitive to Zn excess in terms of growth reduction and H2O2 accumulation, suggesting that the diversities in responses to Zn stress should be ascribed here to inter-varietal metabolic differences. In both cultivars, increased NAD(P)H oxidation rate by pH-dependent peroxidases, and reduced detoxification activity by catalase and peroxidases, were responsible for Zn-induced H2O2 accumulation, while total superoxide dismutase content and activity seemed in general to not change or even depress. Moreover, differences in the content of thiol-peptide compounds (glutathione and phytochelatins) were detected, suggesting indeed the setting up of differential response mechanisms to Zn excess at an inter-varietal and inter-organ level. 相似文献
989.
990.
Agnieszka Matera-Witkiewicz Jolanta ?wi?tek-Koz?owska Alessandro Pratesi Luigi Messori 《Journal of inorganic biochemistry》2009,103(5):678-688
A series of linear tetrapeptides containing two histidyl residues in position 2 and 4, namely DHGH, DHGdH, KHGH, KHGdH, Ac-DHGH-NH2, Ac-DHGdH-NH2, Ac-KHGH-NH2, and Ac-KHGdH-NH2, were synthesized and characterised. Their copper(II) binding properties were investigated in depth through a variety of physicochemical methods. Potentiometric titrations were first carried out to establish the stoichiometry and the stability of the resulting copper(II)-peptide complexes. The copper(II) chromophores that are formed in the various cases in dependence of pH were subsequently characterised by extensive spectroscopic analysis (UV-Vis, EPR, CD) in strict correlation with potentiometric data. The effects of the nature of the first amino acid (Lys versus Asp) and of N-terminal amino group protection on copper(II) binding were specifically addressed. On turn, the careful comparison of the copper(II) coordination abilities of the linear peptides with those of their cyclic analogs provided insight into the effects of cyclization on the overall metal binding properties. 相似文献