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951.
Susana Campoy Jesús Aranda Gerard lvarez Jordi Barb Montserrat Llagostera 《Applied microbiology》2006,72(5):3154-3160
A temperate bacteriophage (F108) has been isolated through mitomycin C induction of a Pasteurella multocida serogroup A strain. F108 has a typical morphology of the family Myoviridae, presenting a hexagonal head and a long contractile tail. F108 is able to infect all P. multocida serogroup A strains tested but not those belonging to other serotypes. Bacteriophage F108, the first P. multocida phage sequenced so far, presents a 30,505-bp double-stranded DNA genome with cohesive ends (CTTCCTCCCC cos site). The F108 genome shows the highest homology with those of Haemophilus influenzae HP1 and HP2 phages. Furthermore, an F108 prophage attachment site in the P. multocida chromosome has been established to be inside a gene encoding tRNALeu. By using several chromosomal markers that are spread along the P. multocida chromosome, it has been demonstrated that F108 is able to perform generalized transduction. This fact, together with the absence of pathogenic genes in the F108 genome, makes this bacteriophage a valuable tool for P. multocida genetic manipulation. 相似文献
952.
Carolina Souza Gusatti Cintia Costi Maria Laura Halon Tarciana Grandi Arlete Ferrari Rech Medeiros Cláudia Maria Dornelles Silva Selma Andrade Gomes Marcia Susana Nunes Silva Christian Niel Maria Lucia Rosa Rossetti 《PloS one》2015,10(8)
Hepatitis B virus genotype A1 (HBV/A1), of African origin, is the most prevalent genotype in Brazil, while HBV/F predominates in the other South American countries. However, HBV/D is the most common in the three states of southern Brazil, where ‘islands’ of elevated prevalence, as Chapecó and other cities, have been described. In this study, 202 HBV chronic carriers attending in 2013 the viral hepatitis ambulatory of Chapecó, were investigated. In comparison with previous studies performed in the same ambulatory, a rapid aging of the HBV infected population was observed (mean age of the newly diagnosed patients increasing from 29.9 ± 10.3 years in 1996 to 44.4 ± 13.3 years in 2013), probably due to a singular vaccination schedule at Chapecó that included not only children but also adolescents. Phylogenetic and BLAST analyses (S region) classified 91 HBV isolates into genotypes A (n = 3) and D (n = 88). The majority of HBV/D isolates were closely related to D3 sequences. To understand the reasons for the absence or near absence of genotypes A and F, and how HBV/D was introduced in the south of Brazil, HBV/D infected patients were inquired about their genealogical and geographical origins. Forty-three (52%) patients have their four grandparents of Italian origin, vs. seven (8%) who have their four grandparents of Brazilian origin. At all, 65 out of 83 (78%) patients had at least one grandparent originating from Italy. Taking into consideration the fact that Italy is one of the few countries where subgenotype D3 is predominant, the results strongly suggested that HBV/D was introduced in Brazil through Italian immigration which culminated between 1870 and 1920. 相似文献
953.
Julie K. K. Vishram Anders Borglykke Anne H. Andreasen J?rgen Jeppesen Hans Ibsen Torben J?rgensen Luigi Palmieri Simona Giampaoli Chiara Donfrancesco Frank Kee Giuseppe Mancia Giancarlo Cesana Kari Kuulasmaa Veikko Salomaa Susana Sans Jean Ferrieres Jean Dallongeville Stefan S?derberg Dominique Arveiler Aline Wagner Hugh Tunstall-Pedoe Wojciech Drygas Michael H. Olsen MORGAM Project 《PloS one》2015,10(5)
954.
Cardoso Susana Correia Sónia Carvalho Cristina Candeias Emanuel Plácido Ana I. Duarte Ana I. Seiça Raquel M. Moreira Paula I. 《Journal of bioenergetics and biomembranes》2015,47(1-2):119-131
Journal of Bioenergetics and Biomembranes - The integrity of mitochondrial function is essential to cell life. It follows that disturbances of mitochondrial function will lead to disruption of cell... 相似文献
955.
956.
Ruben Heleno Cristina Garcia Pedro Jordano Anna Traveset José Maria Gómez Nico Blüthgen Jane Memmott Mari Moora Jorge Cerdeira Susana Rodríguez-Echeverría Helena Freitas Jens M. Olesen 《Biology letters》2014,10(1)
In recent years, the analysis of interaction networks has grown popular as a framework to explore ecological processes and the relationships between community structure and its functioning. The field has rapidly grown from its infancy to a vibrant youth, as reflected in the variety and quality of the discussions held at the first international symposium on Ecological Networks in Coimbra—Portugal (23–25 October 2013). The meeting gathered 170 scientists from 22 countries, who presented data from a broad geographical range, and covering all stages of network analyses, from sampling strategies to effective ways of communicating results, presenting new analytical tools, incorporation of temporal and spatial dynamics, new applications and visualization tools.1 During the meeting it became evident that while many of the caveats diagnosed in early network studies are successfully being tackled, new challenges arise, attesting to the health of the discipline. 相似文献
957.
Mabelyn Córdova-Montejo Miguel Sáenz De Rodrigáñez García Emyr Saul Peña-Marín Rafael Martínez-García Susana Camarillo-Coop Lus M. López 《Marine and Freshwater Behaviour and Physiology》2013,45(4):167-180
ABSTRACTThe objective of this study was to characterize the digestive proteases of totoaba (Totoaba macdonaldi). Fish were sacrificed to obtain the multienzymatic extracts from the stomach and intestine, and determine the stability and optimum pH and temperature values. Residual activity and number of isoforms were determined with some inhibitors. Optimal pH of stomach proteases was 2, with stability above 100% at that same pH. Optimum pH of intestinal proteases was between 9 and 11, with stability above 100% between 8-12. Optimum temperature for stomach proteases was 35°C and remained highly stable, while optimum temperature for intestinal proteases was 45°C, with high stability between 35-55°C. Pepstatin A totally inhibited acid protease activity and revealed a single band. SDS-PAGE zymogram revealed 8 bands in the intestine, where phenanthroline inhibited 80% of the total activity. The digestive capacity of T. macdonaldi is characteristic of a strict carnivore, similar to other marine fish species. 相似文献
958.
Florencia Rojas Molina Susana José de Paggi Demetrio Boltovskoy 《Marine and Freshwater Behaviour and Physiology》2013,45(6):329-338
Limnoperna fortunei is an Asian mussel introduced to South America around 1990. One of the most important impacts of this invader is probably its grazing on the plankton. In this study we evaluate the vulnerability of several planktonic microcrustaceans from the Paraná River floodplain to predation by adult L. fortunei. We conducted 2-h laboratory feeding experiments where the bivalves were offered microcrustaceans differing in overall body shape, size, and locomotive abilities. Ingestion and clearance rates for each taxon were estimated. Results suggest that, in addition to detritus and phytoplankton, microcrustaceans may be a very important food item for this invasive mollusc. Limnoperna fortunei can prey on larger organisms (up to 1100?µm) than Dreissena polymorpha, the European and North American invasive mussel. 相似文献
959.
960.
Gregorio Martínez Sánchez Eduardo Candelario-Jalil Attilia Giuliani Olga-Sonia León Susana Sam Rene Delgado 《Free radical research》2013,47(5):465-473
The effect of oral administration of Mangifera indica L. extract (QF808) on ischemia-reperfusion-induced neuronal death in the gerbil hippocampal CA1 sector was examined. Oral administration of QF808 for 7 days dose-dependently protected against neuronal cell death following transient ischaemia and reperfusion as assessed by histopathology. In addition, locomotor activity assessment prior to ischaemia and 7 days after correlated well with the histological results. To evaluate redox alterations by reactive oxygen species, total sulfhydryl, non-protein sulfhydryl groups (NPSH), malondialdehyde+4-hydroxyalkenals and total nitrogen oxide levels were assayed in hippocampus and cortex homogenates. QF808 treatment attenuated NPSH loss, nitrogen oxide levels and lipid peroxidation in the hippocampus. These results suggest that orally administered QF808 is absorbed across the blood-brain barrier and attenuates neuronal death of the hippocampal CA1 area after ischaemia-reperfusion. These protective effects are most likely due to the antioxidant activity of QF808. 相似文献