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991.
Farzana Islam Rume Alessia Affuso Luigina Serrecchia Valeria Rondinone Viviana Manzulli Emanuele Campese Pietro Di Taranto Paritosh Kumar Biswas Chowdhury Rafiqul Ahsan Mahmuda Yasmin Antonio Fasanella Martin Hugh-Jones 《PloS one》2016,11(4)
In Bangladesh, anthrax, caused by the bacterium Bacillus anthracis, is considered an endemic disease affecting ruminants with sporadic zoonotic occurrences in humans. Due to the lack of knowledge about risks from an incorrect removal of infected carcasses, the disease is not properly monitored, and because of the socio-economic conditions, the situation is under-reported and under-diagnosed. For sensitive species, anthrax represents a fatal outcome with sudden death and sometimes bleeding from natural orifices. The most common source of infection for ruminants is ingestion of spores during grazing in contaminated pastures or through grass and water contaminated with anthrax spores. Domestic cattle, sheep and goats can also become infected through contaminated bone meal (used as feed) originating from anthrax-infected carcasses. The present investigation was conducted to isolate B. anthracis organisms from 169 samples (73 soil, 1 tissue, 4 bone and 91 bone meal samples) collected from 12 different districts of Bangladesh. The sampling was carried out from 2012 to 2015. Twelve samples resulted positive for B. anthracis. Biomolecular analyses were conducted starting from the Canonical Single Nucleotide Polymorphism (CanSNP) to analyze the phylogenetic origin of strains. The analysis of genotype, obtained through the Multiple Locus Variable Number Tandem Repeat Analysis (MLVA) with the analysis of 15 Variable Number Tandem Repeats (VNTR), demonstrated four different genotypes: two of them were previously identified in the district of Sirajganj. The sub-genotyping, conducted with Single Nucleotide Repeats analysis, revealed the presence of eight subgenotypes. The data of the present study concluded that there was no observed correlation between imported cattle feed and anthrax occurrence in Bangladesh and that the remarkable genetic variations of B. anthracis were found in the soil of numerous outbreaks in this country. 相似文献
992.
Zabala F Polidoro P Robie A Branson K Perona P Dickinson MH 《Current biology : CB》2012,22(14):1344-1350
An important role of visual systems is to detect nearby predators, prey, and potential mates, which may be distinguished in part by their motion. When an animal is at rest, an object moving in any direction may easily be detected by motion-sensitive visual circuits. During locomotion, however, this strategy is compromised because the observer must detect a moving object within the pattern of optic flow created by its own motion through the stationary background. However, objects that move creating back-to-front (regressive) motion may be unambiguously distinguished from stationary objects because forward locomotion creates only front-to-back (progressive) optic flow. Thus, moving animals should exhibit an enhanced sensitivity to regressively moving objects. We explicitly tested this hypothesis by constructing a simple fly-sized robot that was programmed to interact with a real fly. Our measurements indicate that whereas walking female flies freeze in response to a regressively moving object, they ignore a progressively moving one. Regressive motion salience also explains observations of behaviors exhibited by pairs of walking flies. Because the assumptions underlying the regressive motion salience hypothesis are general, we suspect that the behavior we have observed in Drosophila may be widespread among eyed, motile organisms. 相似文献
993.
994.
995.
Renato De Pietro 《水生昆虫》2013,35(4):247-259
The male and female of Polycentropus cianficconiae sp. n. (Peloritani Mountains, Northeast Sicily) are described. This new species is related to P. divergens Mosely, 1930, of which the variability of some characters of male genitalia is examined. Female genitalia of the new species are compared to those of P. divergens, P. malickyi Moretti, 1981 and P. mortoni Mosely, 1930. The characters of female genitalia are useful for evaluating the relatedness and differences among the species. They agree with the findings of the study on male genitalia. 相似文献
996.
Renato De Pietro 《水生昆虫》2013,35(4):257-260
Plectrocnemia alicatai sp.n. from Sicily (Nebrodi Mountains) is described and figured from the adult male. 相似文献
997.
998.
Andrea Calderan Paolo Ruzza Biancamaria Ancona Lorenzo Cima Pietro Giusti Gianfranco Borin 《International journal of peptide research and therapeutics》1998,5(2-3):71-73
Summary Dermorphin structure-activity relationships toward μ and δ opioid receptors were investigated using a series of synthetic
peptides, in which the aromatic residues at positions 1 or/and 3 of the N-terminal tetrapeptide analogue H-Tyr-d-Arg-Phe-β-Ala-NH2 were replaced by unnatural or constrained amino acids. 相似文献
999.
The aim of this work has been to analyse the effects of temperature on polystyrene adhesion ofPseudomonas aeruginosa ATCC 27853. The bacterial adhesion (expressed as percentage of hydrophobicity) has been measured during the cultivation of this strain at different temperature of growth (15, 30 and 47°C). Data obtained showed that an increase in temperature is a factor that increasing the virulence of the strain in terms of adhesion to polystyrene surfaces. This kind of experiments surely brings important information concerning the prevention of nosocomial infection. 相似文献
1000.
G. Corea A. Di Pietro C. Dumontet E. Fattorusso V. Lanzotti 《Phytochemistry Reviews》2009,8(2):431-447
A phytochemical investigation of the aerial parts of Euphorbia spp., considered one of the most common elements of Mediterranean landascape, led to the isolation of a large number of bioactive
plant metabolites, belonging to the diterpenes family. Above all, over seventy jatrophane, modified jatrophane, segetane,
pepluane, and paraliane diterpenoids, fifty of them reported for the first time, were extracted, purified and characterized
from Euphorbia dendroides, Euphorbia characias, Euphorbia peplus, Euphorbia paralias and Euphorbia helioscopia. These compounds showed interesting pharmacological activities. In particular, jatrophanes, modified jatrophanes and lathyranes
exhibited a potent inhibitory activity against P-glycoprotein (Pgp), a membrane protein that confers cellular ability to resist
lethal doses of certain cytotoxic drugs by pumping them to the outside, thus resulting in a reduced cytotoxicity. Among the
others, our chemical survey led to isolation of the most powerful inhibitors of daunomycin-efflux activity isolated to date
for this class of inhibitors, named euphodendroidin D and pepluanin A. Their efficiency was found to be at least two-fold
higher than the conventional modulator cyclosporin A, taken as a reference. In addition, the isolation of a high number of
natural structurally-related analogues allowed us to perform Structure Activity Relationship (SAR) studies, without any chemical
modification, which gave information on the key pharmacophoric elements of these new class of promising drugs. A further set
of diterpene analogues, very recently isolated from sun spurge, E. helioscopia, individually investigated for their Pgp- and BCRP-inhibiting properties, appeared to be specific inhibitors of Pgp since
they showed no significant activity against BCRP, thus resembling to the third-generation class of specific MDR inhibitors. 相似文献