Characteristics of some Phytophthora species isolated from oak forest soils in central and northern Italy.

Four Phytophthora species, P. citricola, P. megasperma, P. quercina and P. syringae, were isolated during a systematic survey of oak forests (Quercus cerris and Q. robur) in Tuscany (central Italy), and in the Po Valley and the Venetian Plain (northern Italy) from 22 out of 54 soil samples. The main morphological characteristics of the isolates and their growth rates on different substrates and at different temperatures are reported

Evaluation of indigenous entomopathogenic nematodes as potential biocontrol agents against popillia japonica (Coleoptera: Scarabaeidae) in Northern Italy

The natural presence of entomopathogenic nematodes (EPNs) has been investigated in the Piedmont region (Northern Italy) in areas infested by the Japanese beetle Popillia japonica. Thirty-nine out of 155 soil samples (25.2%) were positive for EPNs. Most of the samples contained only steinermatids (92.3%), 5.1% contained heterorhabditids, and one sample (2.6%) contained both genera. All the recovered isolates were identified at species level both morphologically and molecularly. Steinernema carpocapsae was the most abundant and it was mainly distributed in open habitats, such as perennial meadows, uncultivated soils, and cropland, characterized by sandy loam soil texture and acidic pH. Steinernema feltiae has been found associated mainly with closed habitats such as coniferous and deciduous woodland, characterized by sandy loam-texture and extremely acidic soil. The three isolates of Heterorhabditis bacteriophora were collected only in open habitats (perennial meadows and uncultivated fields) characterized by strongly acidic soils with sandy loam texture. The virulence of all EPN natural strains was evaluated by laboratory assays against P. japonica third-instar larvae collected during two different periods of the year (spring, autumn). The results showed that larval mortality was higher for pre-wintering larvae than post-wintering ones. The five more promising EPN isolates were tested in the semi-field assay in which H. bacteriophora natural strains have been shown to be more efficient in controlling P. japonica grubs. All of these results are finally discussed considering the use of these natural EPNs as biological control agents against P. japonica, within an eco-friendly perspective of management

Antimicrobial activity of the red palm weevil Rhynchophorus ferrugineus

The red palm weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera Dryophthoridae), is an important pest of palms. Knowl- edge of both its natural enemies and its defensive mechanisms against predators and microorganisms is important to develop methods for an integrated pest control. Antimicrobial activity of the cuticular surface of adults and larvae, as well as of eggs, of this invasive species was investigated. This activity was tested against the Gram-positive bacteria Bacillus subtilis (Ehrenberg) Cohn and Bacillus thuringiensis Berliner, the Gram-negative bacterium Escherichia coli Escherich, and the entomopathogenic fungi Beauveria bassiana (Balsamo) Vuillemin and Metarhizium anisopliae (Metchnikoff) Sorokin. A similar analysis was con- ducted with the hemolymph of R. ferrugineus\u2019 larvae infected by Pseudomonas aeruginosa (Schroter) Migula, E. coli and Staphy- lococcus aureus Rosenbach. Polar surface fraction of extracts from adults and large larvae inhibits Gram-positive bacteria and the B. bassiana\u2019s growth, but not the growth of E. coli and M. anisopliae. Similarly, the hemolymph of larvae and the surface extracts of both small larvae and eggs seemed not to show any inhibition. Chemical analyses of the fraction exhibiting antimicrobial activ- ity show the presence of some polar compounds ranging between 1000 and 1500 Dalton. This study improves our knowledge on the biology of R. ferrugineus and helps to suggest strategies for the biocontrol of this pest

Complex I-Associated Hydrogen Peroxide Production Is Decreased and Electron Transport Chain Enzyme Activities Are Altered in n-3 Enriched fat-1 Mice

The polyunsaturated nature of n-3 fatty acids makes them prone to oxidative damage. However, it is not clear if n-3 fatty acids are simply a passive site for oxidative attack or if they also modulate mitochondrial reactive oxygen species (ROS) production. The present study used fat-1 transgenic mice, that are capable of synthesizing n-3 fatty acids, to investigate the influence of increases in n-3 fatty acids and resultant decreases in the n-6∶n-3 ratio on liver mitochondrial H2O2 production and electron transport chain (ETC) activity. There was an increase in n-3 fatty acids and a decrease in the n-6∶n-3 ratio in liver mitochondria from the fat-1 compared to control mice. This change was largely due to alterations in the fatty acid composition of phosphatidylcholine and phosphatidylethanolamine, with only a small percentage of fatty acids in cardiolipin being altered in the fat-1 animals. The lipid changes in the fat-1 mice were associated with a decrease (p<0.05) in the activity of ETC complex I and increases (p<0.05) in the activities of complexes III and IV. Mitochondrial H2O2 production with either succinate or succinate/glutamate/malate substrates was also decreased (p<0.05) in the fat-1 mice. This change in H2O2 production was due to a decrease in ROS production from ETC complex I in the fat-1 animals. These results indicate that the fatty acid changes in fat-1 liver mitochondria may at least partially oppose oxidative stress by limiting ROS production from ETC complex I

Docetaxel and gemcitabine activity in NSCLC cell lines and in primary cultures from human lung cancer

The activity of the following drugs was investigated in two established NSCLC cell lines: docetaxel, gemcitabine, vinorelbine, paclitaxel, doxorubicin (0.01, 0.1, 1 μg ml−1), cisplatin, ifosfamide (1, 2, 3 μg ml−1) and carboplatin (2, 4, 6 μg ml−1). The cytotoxic activity was evaluated by the sulphorhodamine B assay. The two most active drugs, docetaxel and gemcitabine, used singly and in association, were investigated as a function of treatment schedule. The sequence docetaxel→gemcitabine produced only a weak synergistic interaction in RAL but a strong synergism in CAEP cells. The synergistic interaction increased in both cell lines after a 48-h washout between the drug administrations. Flow cytometric analysis showed that in docetaxel→gemcitabine sequence, docetaxel produced a block in G2/M phase and, after 48 h, provided gemcitabine with a large fraction of recovered synchronized cells in the G1/S boundary, which is the specific target phase for gemcitabine. Conversely, simultaneous treatment induced an antagonistic effect in both cell lines, and the sequential scheme gemcitabine→docetaxel produced a weak synergistic effect only in RAL cells. Moreover, the synergistic interaction disappeared when washout periods of 24 or 48 h between two drug administrations were adopted. The synergistic activity of docetaxel→ 48-h washout→gemcitabine was confirmed in 11 of 14 primary cultures, which represents an important means of validating experimental results before translating them into clinical practice. © 1999 Cancer Research Campaig

(HFEPR)-E-2 spectroscopy of Fe(III) impurities in a blue hercynite-based pigment

The nature and the behavior of a paramagnetic Fe(III) impurity, occurring in anew charge-transfer hercynite-based blue pigment and determined through conventional electron paramagnetic resonance (EPR) and Mossbauer spectroscopy, was investigated and ascertained through high-field high-frequency EPR ((HFEPR)-E-2) spectroscopy. The blue hercynite-based pigment is biphasic, containing both hercynite and corundum. The (HFEPR)-E-2 spectral features. together with their temperature dependence allowed to assess the intensity and the symmetry of the Fe(III) crystal field interactions. Numerical simulations were used to determine the relevant hamiltonian parameters. The final attribution of Fe(III) to the octahedral sites in corundum was achieved. The presence of corundum was found to remove ferric iron, eventually formed during the synthesis, from hercynite. The dilution of Fe(III) in the Al2O3 phase results in a quenching of its coloring effects. As a consequence, corundum acts as a buffer during the synthesis, stabilizing the pigment chromatic yield. (c) 2005 Elsevier Ltd. All rights reserved