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Delia Cavallo Alessandro Marinaccio Barbara Perniconi Paola Tomao Vittorio Pecoriello Roberto Moccaldi Sergio Iavicoli 《Mutation research》2002,513(1-2):11-15
The increasing use of air travel suggests the need for risk assessment and cytogenetic analysis of flight personnel, to check for the risk of developing cancer. Taking into consideration occupational risk and possible confounding factors, we used traditional cytogenetics, the micronucleus test and fluorescent in situ hybridization (FISH) analysis to study 48 male crew members working on long-haul flights and a control group of 48 ground staff. Compared to controls, we detected a significant increase in the relative risk of gaps and breaks (adjusted odds ratio (OR(adj))--7.8; 95% confidence interval (CI) - 2.4-24.9) and of translocations (OR(adj)--5.1; 95% CI 1.5-17.3) in crew members, with a non-significant difference in the other chromosomal aberrations. The possibility of a correlation between translocations and cancer risk highlights the need for preventive measures for aircraft personnel. 相似文献
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The Coxiella burnetii icd gene encoding an immunogenic dimeric NADP(+)-dependent isocitrate dehydrogenase (IDH) was cloned by screening a C. burnetii genomic library with a human positive serum and sequenced. The predicted gene product consists of 427 amino acids (M(r) = 46,600) and showed high identity to the IDHs of Escherichia coli (74%), Salmonella enterica (73%) and IDH-I of Vibrio sp. (71%). The cloned gene complemented an icd-defective E. coli mutant producing a recombinant IDH that had the same biochemical properties as the enzyme from purified C. burnetii. Unlike the homologs from other bacteria, the cloned enzyme was expressed to the highest level in low pH conditions. This distinct property of the cloned IDH suggests that C. burnetii icd gene may have a role in the adaptation of the organism to the harsh acidic environment of the eucaryotic phagolysosomes. 相似文献
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Loredana Salerno Luca Vanella Valeria Sorrenti Valeria Consoli Valeria Ciaffaglione Antonino N. Fallica Vittorio Canale Pawe Zajdel Rosario Pignatello Sebastiano Intagliata 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):1378
In this work, the first mutual prodrug of 5-fluorouracil and heme oxygenase1 inhibitor (5-FU/HO-1 hybrid) has been designed, synthesised, and evaluated for its in vitro chemical and enzymatic hydrolysis stability. Predicted in silico physicochemical properties of the newly synthesised hybrid (3) demonstrated a drug-like profile with suitable Absorption, Distribution, Metabolism, and Excretion (ADME) properties and low toxic liabilities. Preliminary cytotoxicity evaluation towards human prostate (DU145) and lung (A549) cancer cell lines demonstrated that 3 exerted a similar effect on cell viability to that produced by the reference drug 5-FU. Among the two tested cancer cell lines, the A549 cells were more susceptible for 3. Of note, hybrid 3 also had a significantly lower cytotoxic effect on healthy human lung epithelial cells (BEAS-2B) than 5-FU. Altogether our results served as an initial proof-of-concept to develop 5-FU/HO-1 mutual prodrugs as potential novel anticancer agents. 相似文献
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Contact languages are born out of the non-trivial interaction of two (or more) parent languages. Nowadays, the enhanced possibility of mobility and communication allows for a strong mixing of languages and cultures, thus raising the issue of whether there are any pure languages or cultures that are unaffected by contact with others. As with bacteria or viruses in biological evolution, the evolution of languages is marked by horizontal transmission; but to date no reliable quantitative tools to investigate these phenomena have been available. An interesting and well documented example of contact language is the emergence of creole languages, which originated in the contacts of European colonists and slaves during the 17th and 18th centuries in exogenous plantation colonies of especially the Atlantic and Indian Ocean. Here, we focus on the emergence of creole languages to demonstrate a dynamical process that mimics the process of creole formation in American and Caribbean plantation ecologies. Inspired by the Naming Game (NG), our modeling scheme incorporates demographic information about the colonial population in the framework of a non-trivial interaction network including three populations: Europeans, Mulattos/Creoles, and Bozal slaves. We show how this sole information makes it possible to discriminate territories that produced modern creoles from those that did not, with a surprising accuracy. The generality of our approach provides valuable insights for further studies on the emergence of languages in contact ecologies as well as to test specific hypotheses about the peopling and the population structures of the relevant territories. We submit that these tools could be relevant to addressing problems related to contact phenomena in many cultural domains: e.g., emergence of dialects, language competition and hybridization, globalization phenomena. 相似文献