The effects of fire on communities,guilds and species of breeding birds in burnt and control pinewoods in central Italy

Breeding bird communities in burnt and unburnt residual pinewoods were studied over 3 years by line-transect method, following a catastrophic fire event in Castelfusano (Rome, Central Italy; July 2000). We applied bootstrap procedures to evaluate whether the observed data were true or just produced by chance, and then examined the emerging patterns at three levels: community, guild and species levels. At the community level, fire acted on breeding bird communities by altering especially the total abundance patterns: the species abundance decreased in the burnt pinewood compared to the residual one, but other parameters were not significantly affected by fire. As a consequence of fire, the destruction and structural simplification of the canopy and shrubby component, as well as the increase of edge habitat and patchiness at landscape scale, induced a turnover in species between pinewoods. Species turnover was higher at the burnt than at the residual pinewoods, during all the 3 years of study. At the guild level, the forest species decreased strongly in terms of richness and abundance in the burnt pinewoods, contrary to the edge and open habitat species which increased in terms of richness, abundance and evenness. Edge species showed the highest turnover in burnt pinewood during the whole period of study. At species level, after an a priori subdivision (based on bibliographic search) of the various species in two ecological guilds (forest versus edge species), it was found that an a posteriori statistical analysis confirmed the expected trend, i.e. that the species which decreased significantly in burnt pinewood were essentially the forest species, whereas the species which increased were essentially the edge/open habitat ones. Overall, in order to investigate the effects of fire catastrophes on birds, the guild approach seems more exhaustive than the taxonomic community approach, where intrinsic confounding trends are present.     

Compost-based growing media: influence on growth and nutrient use of bedding plants

The agronomic performance and the mineral composition and trace element content in Begonia semperflorens "Bellavista F1", Mimulus "Magic x hybridus", Salvia splendens "maestro", and Tagete patula xerecta "Zenith Lemon Yellow", were tested by growing the plants on substrates of white peat and 25-50-75-100% green waste and sewage sludge (80%+20%v/v) compost (CP). A commercial peat medium of black and white peat (2:1v/v) was used as control. At flowering, the agronomic parameters were compared by ANOVA and plant nutritional status was compared by vector analysis. Substrate-species interactions (P<0.001) were evident for all measured parameters. In the 25% CP medium all the species showed an increase or preservation of the studied agronomic parameters. Begonia grown in 25% CP, showed the highest dry weight (DW) and number of flowers. Other treatments were comparable to the control. Mimulus and Salvia showed the highest DW in the 25-50% CP. Mimulus, after a DW increase up to 50% CP, showed the steepest reduction as the CP increased further. Tagete showed no differences in DW up to 50% CP, or in flower number up to 25% CP, compared to the control. The additional increases of CP in the medium showed a DW decrease similar to that of Salvia. Vector analysis showed the use of compost mainly induced a decrease of P concentration in tissues, except for Begonia which remained unchanged. Plant tissues showed a general P reduction due to a dilution effect in the low compost mixtures (25-50%) and a deficiency in the higher CP mixtures. In contrast, an increase of Mg in the aboveground tissues of all species was detectable as compost usage increased, with the exception of Salvia which suffered a Mg deficiency. Vector analysis also highlighted a Ni and partial Fe deficiency in Tagete and Salvia.     

Priming by airborne signals boosts direct and indirect resistance in maize

Plants counteract attack by herbivorous insects using a variety of inducible defence mechanisms. The production of toxic proteins and metabolites that instantly affect the herbivore's development are examples of direct induced defence. In addition, plants may release mixtures of volatile organic compounds (VOCs) that indirectly protect the plant by attracting natural enemies of the herbivore. Recent studies suggest that these VOCs can also prime nearby plants for enhanced induction of defence upon future insect attack. However, evidence that this defence priming causes reduced vulnerability to insects is sparse. Here we present molecular, chemical and behavioural evidence that VOC-induced priming leads to improved direct and indirect resistance in maize. A differential hybridization screen for inducible genes upon attack by Spodoptera littoralis caterpillars identified 10 defence-related genes that are responsive to wounding, jasmonic acid (JA), or caterpillar regurgitant. Exposure to VOCs from caterpillar-infested plants did not activate these genes directly, but primed a subset of them for earlier and/or stronger induction upon subsequent defence elicitation. This priming for defence-related gene expression correlated with reduced caterpillar feeding and development. Furthermore, exposure to caterpillar-induced VOCs primed for enhanced emissions of aromatic and terpenoid compounds. At the peak of this VOC emission, primed plants were significantly more attractive to parasitic Cotesia marginiventris waSPS. This study shows that VOC-induced priming targets a specific subset of JA-inducible genes, and links these responses at the molecular level to enhanced levels of direct and indirect resistance against insect attack.     

New 1,8-naphthyridine and quinoline derivatives as CB2 selective agonists

A series of new 1,8-naphthyridine and quinoline derivatives were synthesized and evaluated for their cannabinoid receptor affinity. In particular, compounds 2, 5, 11, and 13 showed a high CB(2) affinity and CB(2) versus CB(1) selectivity, in agreement with molecular modeling studies. Furthermore, compound 2 also exhibited in vivo antinociceptive effects.     

Bradykinin B1 antagonists: biphenyl SAR studies in the cyclopropanecarboxamide series

SAR study of the biphenyl region of cyclopropanecarboxamide derived bradykinin B(1) antagonists was examined. Incorporation of a pyridine in place of the proximal phenyl ring and chlorination of the distal phenyl ring proved to be well tolerated and provided compounds with improved pharmacokinetic profiles, CNS penetration, and enhanced receptor occupancy.     

Specific interactions with intra- and intermolecular G-quadruplex DNA structures by hydrosoluble coronene derivatives: a new class of telomerase inhibitors

In developing G-quadruplex interactive telomerase inhibitors two main features have to be taken into account: the hydrophobic interactions with the G-quartet plane and the electrostatic interactions with the negatively charged phosphates of the four grooves. In this paper, we report the synthesis of four hydrosoluble coronene derivatives, which are characterized by a large hydrophobic aromatic core and four orthogonal hydrophilic side chains. We have studied their ability to induce both inter- and intramolecular G-quadruplex structures and found a significant selectivity of all the coronene derivatives for the intramolecular G-quadruplex. The efficiency in inhibiting human telomerase has been evaluated in a cell-free system and the experimental results correlate with the relative affinities of these compounds for the G-quadruplex monomeric structure, as derived by molecular modelling simulations. Thus, the coronene derivatives can be considered as a new class of telomerase inhibitors, although further investigations are surely necessary to fully exploit their features.     

Structure of a 14-3-3 coordinated hexamer of the plant plasma membrane H+ -ATPase by combining X-ray crystallography and electron cryomicroscopy

Regulatory 14-3-3 proteins activate the plant plasma membrane H(+)-ATPase by binding to its C-terminal autoinhibitory domain. This interaction requires phosphorylation of a C-terminal, mode III, recognition motif as well as an adjacent span of approximately 50 amino acids. Here we report the X-ray crystal structure of 14-3-3 in complex with the entire binding motif, revealing a previously unidentified mode of interaction. A 14-3-3 dimer simultaneously binds two H(+)-ATPase peptides, each of which forms a loop within the typical 14-3-3 binding groove and therefore exits from the center of the dimer. Several H(+)-ATPase mutants support this structure determination. Accordingly, 14-3-3 binding could result in H(+)-ATPase oligomerization. Indeed, by using single-particle electron cryomicroscopy, the 3D reconstruction of the purified H(+)-ATPase/14-3-3 complex demonstrates a hexameric arrangement. Fitting of 14-3-3 and H(+)-ATPase atomic structures into the 3D reconstruction map suggests the spatial arrangement of the holocomplex.     

Relaxing effects of 5-oxo-ETE on human bronchi involve BK Ca channel activation

The present study investigated the ability of 5-oxo-EicosaTetraEnoic acid (5-oxo-ETE) for modulating airway smooth muscle (ASM) tone in human bronchi. 5-Oxo-ETE induced a concentration-dependent relaxing effect on human bronchi pre-contracted with methacholine (MCh) and arachidonic acid (AA). This relaxing response was highly sensitive to Iberiotoxin (IbTx), a large conducting Ca(2+)-activated K(+) channel (BK(Ca)) inhibitor. Furthermore, microelectrode measurements revealed that 5-oxo-ETE (0.1-10 microM) hyperpolarizes the membrane potential of human bronchial ASM cells. These hyperpolarizing effects were also inhibited in the presence of 10nM IbTx. Lastly, 5-oxo-ETE was shown to directly activate reconstituted BK(Ca) channels derived from human airway smooth muscles. In summary, the 5-oxo-ETE eicosanoid activates a specific K(+) conductance, involved in membrane hyperpolarization, which in turn reduces Ca(2+) entry and facilitates relaxation of smooth muscle cells.     

Development and clinical validation of a real-time PCR using a uni-molecular Scorpion-based probe for the detection of Mycoplasma pneumoniae in clinical isolates

Mycoplasma pneumoniae (Mp) is a frequent cause of Community Acquired Pneumoniae (CAP). The etiological role of Mp is usually suspected using serological assays, but the detection of specific anti-Mp antibodies becomes possible only 1-2 weeks after the primary infection. On the contrary, direct diagnosis using real-time PCR allows an efficient detection of Mp DNA in all the phases of the infection and particularly during early serum negative periods. In this study, we developed a novel Scorpion-probe real-time PCR-based assay. The probe's uni-molecular structure offers thermodynamic advantages owing to its kinetic reaction, providing faster performances compared to a TaqMan-based assay, but maintaining the same sensitivity and specificity. The Scorpion-based assay was employed on 388 clinical samples and compared with conventional qualitative PCR and serological tests. It was found more sensitive because it also allowed the detection of Mp in specimens found negative using classic qualitative PCR, but displaying seropositivity or a later seroconversion.     

Antibiotic resistance in long-term care facilities

Long-term-care facilities (LTCFs) comprise a heterogeneous group of institutions that provide a wide variety of services to diverse groups of patients, most of whom are elderly. Infections are common in LTCFs and these are complicated by antimicrobial-resistant pathogens. The residents in LTCFs have a high frequency of colonization with antimicrobial-resistant organisms, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, penicillin-resistant pneumococci, extended spectrum P-lactamase-producing gram-negative organisms, and fluoroquinolone-resistant gram-negative organisms. Although several control programs have been published, up to now there still is a long way to go in this area of health care. This review will briefly touch upon the clinical relevance of antimicrobial resistance in LTCFs.