1,151 research outputs found

    Clearance and persistence of Escherichia coli in the freshwater mussel Unio mancus

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    The excessive use of antibiotics has led to the emergence of resistant bacteria, mainly from the Enterobacterales group, with high pathogenic/zoonotic potentials that can lead to problems in public health. The increasing presence in freshwater ecosystems highlights the need to evaluate potential sentinel species as risk indicators for both ecosystem and human health. The freshwater mussels provide several ecosystem services, may represent potential sentinel species due to their ability to filter water and retain both organic and inorganic particles. We tested the capability of U. mancus to retain Escherichia coli as a model bacterial organism. Under experimental conditions, the mussels could clear suspended E. coli, facilitating its rapid elimination from water within the first 24 h after exposure. The species also presented a maximum retention time of 4 days. We also provide allometric equations correlating the filtering capacity with the length and the weight of mussel body parts often used in biometric studies. We provide a first assessment of the potential of the bivalve Unio mancus to act as a sentinel species for the detection of Enterobacterales and demonstrate the ability to act as a water cleaner.info:eu-repo/semantics/publishedVersio

    Cytotaxonomy and karyotype evolution in Neotropical Meliponini (Hymenoptera: Apidae) inferred by chromosomal mapping of 18S rDNA and five microsatellites.

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    The Neotropical Meliponini bees, commonly known as stingless bees, are phylogenetically subdivided into three clades in which the chromosome numbers vary from n 1⁄4 8 to n 1⁄4 17. The goal of this study was to identify the major chromosomal rearrangements that occurred during the Neotropical Meliponini (Apidae) karyotypic evolution. In this way, we mapped 18S rDNA and five microsatellites in 33 stingless bee species collected from different Brazilian regions. The species belonged to 15 genera and showed six different chromosome numbers: n 1⁄4 8, n 1⁄4 9, n 1⁄4 11, n 1⁄4 14, n 1⁄4 15, and n 1⁄4 17. The 18S rDNA probe showed a variation from 2 to 12 marked chromosomes in different positions (terminal, subterminal, or centromeric), including 2 B chromosomes out of the 7 B found in Tetragonisca fiebrigi. The microsatellite (GA)15, (GAG)10, (CAA)10, and (TCAGG)6 probes formed clusters on the euchromatic regions of the chromosomes and were useful in the identification of putative Robertsonian fusion events that led to the decrease in the chromosome number during the evolution of the Neotropical Meliponini clade. (TTAGG)6 constituted the telomeric sequence of the analyzed species. The ancestral state of the three Neotropical Meliponini clades is difficult to infer, although, the putative ancestral karyotype probably had a single pair of 18S rDNA cistrons, and the decrease in chromosome number and increase in the 18S rDNA sites occurred independently between genera.Online first

    Spontaneous R-Parity violation bounds

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    We investigate bounds from tree-level and one-loop processes in generic supersymmetric models with spontaneous R-parity breaking in the superpotential. We analyse the bounds from a general point of view. The bounds are applicable both for all models with spontaneous R-parity violation and for explicit bilinear R-parity violation based on general lepton-chargino and neutrino-neutralino mixings. We find constraints from semileptonic B, D and K decays, leptonic decays of the mu and tau, electric dipole moments, as well as bounds for the anomalous magnetic moment of the muon.Comment: 22 page

    Characterization of oral enterobacteriaceae prevalence and resistance profile in chronic kidney disease patients undergoing peritoneal dialysis

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    Chronic Kidney Disease (CKD) is a growing public-health concern worldwide. Patients exhibit compromised immunity and are more prone to infection than other populations. Therefore, oral colonization by clinically relevant members of the Enterobacteriaceae family, major agents of both nosocomial and dialysis-associated infections with frequent prevalence of antibiotic resistances, may constitute a serious risk. Thus, this study aimed to assess the occurrence of clinically relevant enterobacteria and their antibiotic resistance profiles in the oral cavity of CKD patients undergoing peritoneal dialysis (CKD-PD) and compare it to healthy controls. Saliva samples from all the participants were cultured on MacConkey Agar and evaluated regarding the levels of urea, ammonia, and pH. Bacterial isolates were identified and characterized for antibiotic resistance phenotype and genotype. The results showed that CKD-PD patients exhibited significantly higher salivary pH, urea, and ammonia levels than controls, that was accompanied by higher prevalence and diversity of oral enterobacteria. Out of all the species isolated, only the prevalence of Raoultella ornithinolytica varied significantly between groups, colonizing the oral cavity of approximately 30% of CKD-PD patients while absent from controls. Antibiotic resistance phenotyping revealed mostly putative intrinsic resistance phenotypes (to amoxicillin, ticarcillin, and cephalothin), and resistance to sulfamethoxazole (~43% of isolates) and streptomycin (~17%). However, all isolates were resistant to at least one of the antibiotics tested and multidrug resistance isolates were only found in CKD-PD group (31,6%). Mobile genetic elements and resistance genes were detected in isolates of the species Raoultella ornithinolytica, Klebsiella pneumoniae, Klebsiella oxytoca, Escherichia coli, and Enterobacter asburiae, mostly originated from CKD-PD patients. PD-related infection history revealed that Enterobacteriaceae were responsible for ~8% of peritonitis and ~ 16% of exit-site infections episodes in CKD-PD patients, although no association was found to oral enterobacteria colonization at the time of sampling. The results suggest that the CKD-induced alterations of the oral milieu might promote a dysbiosis of the commensal oral microbiome, namely the proliferation of clinically relevant Enterobacteriaceae potentially harboring acquired antibiotic resistance genes. This study highlights the importance of the oral cavity as a reservoir for pathobionts and antibiotic resistances in CKD patients undergoing peritoneal dialysis.info:eu-repo/semantics/publishedVersio

    Métodos de utilização de pastagem cultivada de inverno na suplementação do campo natural

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    An improved pasture composed of Italian ryegrass (Lolium multiflorum), birdsfoot trefoil (Lotus corniculatus), and white dover (Trifolium repens var. ladino) was used in a study of schemes of winter-season supplementation of natural pastures in the Rio Grande do Sul state of Brazil. Nine month old weaned heifers of 5:3 Angus-Zebu stock were used in the study which lasted 111 days. The following schemes of alternation at improved and unimproved pasture were used 1) one week improved, one week unimproved; 2) one week improved, two weeks unimproved; 3) one week improved, three weeks unimproved; 4) two weeks improved, one week unimproved ; 5) two weeks improved, two weeks unimproved; 6) two weeks improved, three weeks unimproved 7) continuous improved pasture. A stocking rate of two animals per hectare was used on the improved pasture and 0.7 on the unimproved. Highly significant differences (p > 0.1) in weight gains were observed among the different treatments, The animals which remained continuously on the improved pastures (treatment 7) showed the greatest gains. Among the other treatments, the greatest gains were shown when the animals remained equal or greater periods on the improved than unimproved pastures. There were no significant differences between one and two week schemes of alternation (treatments 1 and  5) when the ratio of improved to unimproved pasture remainded the same. Economic analysis showed the treatments producing the greatest gains also to be the most profitable.A pastagem cultivada de inverno, constituída de azevém (Lolium multiflorum), comichão (Lotus corniculatus) e trevo branco ladino (Trifolium repens var. ladino), foi utilizada num experimento de suplementação do campo natural durante o inverno, num período de 111 dias e fazendo variar o tempo de permanência dos animais nessa pastagem. Usaram-se fêmeas desmamadas, de 9 meses de idade e de grau de sangue 5:3 Angus-Zebu. Como unidade de permanência em pastagem cultivada foi tomada a semana, estabelecendo-se os seguintes tratamentos I) uma semana em pastagem cultivada e uma semana em pastagem natural; II) uma semana em pastagem cultivada e duas semanas em pastagem natural; III) uma semana em pastagem cultivada e três semanas em pastagem natural; IV) duas semanas em pastagem cultivada e uma semana em pastagem natural; V) duas semanas em pastagem cultivada e duas semanas em pastagem natural; VI) duas semanas em pastagem cultivada e três semanas em pastagem natural; VII) todo o período em pastagem cultivada. Todos os tratamentos obedeceram à lotação de 2,0 animais/ha em pastagem cultivada e de 0,7 animal/ha em campo nativo. Houve uma diferença altamente significativa (P <0,01) entre os tratamentos, no que se refere aos ganhos de peso. Os animais que permaneceram todo o período em pastagem cultivada (trat. VII) apresentaram os maiores ganhos. Havendo alternância na utilização dos pastos, os melhores ganhos foram obtidos quando os animais permaneceram em pastagem cultivada um período igual ou maior do que o em campo natural. Não houve diferença estatística (P < 0,01) quando foi utilizado o mesmo percentual de pastagem cultivada (26,0%) em relação à área de campo nativo (tratamentos V e I), quando os períodos de alternância eram de duas e uma semana, respectivamente. Na apreciação dos resultados deste experimento, infere-se que os ganhos são proporcionais ao maior período de utilização de pastagem em relação ao campo nativo. Os tratamentos com maiores ganhos foram, também, os economicamente mais compensadores

    Advances in infrastructures and tools for multiagent systems

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    In the last few years, information system technologies have focused on solving challenges in order to develop distributed applications. Distributed systems can be viewed as collections of service-provider and ser vice-consumer components interlinked by dynamically defined workflows (Luck and McBurney 2008).Alberola Oltra, JM.; Botti Navarro, VJ.; Such Aparicio, JM. (2014). Advances in infrastructures and tools for multiagent systems. Information Systems Frontiers. 16:163-167. doi:10.1007/s10796-014-9493-6S16316716Alberola, J. M., Búrdalo, L., Julián, V., Terrasa, A., & García-Fornes, A. (2014). An adaptive framework for monitoring agent organizations. Information Systems Frontiers, 16(2). doi: 10.1007/s10796-013-9478-x .Alfonso, B., Botti, V., Garrido, A., & Giret, A. (2014). A MAS-based infrastructure for negotiation and its application to a water-right market. Information Systems Frontiers, 16(2). doi: 10.1007/s10796-013-9443-8 .Andrighetto, G., Castelfranchi, C., Mayor, E., McBreen, J., López-Sánchez, M., & Parsons, S. (2013). (Social) norm dynamics. In G. Andrighetto, G. Governatori, P. Noriega, & L. W. van der Torre (Eds.), Normative multi-agent systems (pp. 135–170). Dagstuhl: Schloss Dagstuhl--Leibniz-Zentrum fuer Informatik.Baarslag, T., Fujita, K., Gerding, E. H., Hindriks, K., Ito, T., Jennings, N. R., et al. (2013). Evaluating practical negotiating agents: results and analysis of the 2011 international competition. Artificial Intelligence, 198, 73–103.Boissier, O., Bordini, R. H., Hübner, J. F., Ricci, A., & Santi, A. (2013). Multi-agent oriented programming with JaCaMo. Science of Computer Programming, 78(6), 747–761.Campos, J., Esteva, M., López-Sánchez, M., Morales, J., & Salamó, M. (2011). Organisational adaptation of multi-agent systems in a peer-to-peer scenario. Computing, 91(2), 169–215.Carrera, A., Iglesias, C. A., & Garijo, M. (2014). Beast methodology: an agile testing methodology for multi-agent systems based on behaviour driven development. Information Systems Frontiers, 16(2). doi: 10.1007/s10796-013-9438-5 .Criado, N., Such, J. M., & Botti, V. (2014). Norm reasoning services. Information Systems Frontiers, 16(2). doi: 10.1007/s10796-013-9444-7 .Del Val, E., Rebollo, M., & Botti, V. (2014). Enhancing decentralized service discovery in open service-oriented multi-agent systems. Journal of Autonomous Agents and Multi-Agent Systems, 28(1), 1–30.Denti, E., Omicini, A., & Ricci, A. (2002). Coordination tools for MAS development and deployment. Applied Artificial Intelligence, 16(9–10), 721–752.Dignum, V., & Dignum, F. (2012). A logic of agent organizations. Logic Journal of IGPL, 20(1), 283–316.Ferber, J., & Gutknecht, O. (1998). A meta-model for the analysis and design of organizations in multi-agent systems. In Multi agent systems. Proceedings. International Conference on (pp. 128–135). IEEE.Fogués, R. L., Such, J. M., Espinosa, A., & Garcia-Fornes, A. (2014). BFF: a tool for eliciting tie strength and user communities in social networking services. Information Systems Frontiers, 16(2). doi: 10.1007/s10796-013-9453-6 .Garcia, E., Giret, A., & Botti, V. (2011). Evaluating software engineering techniques for developing complex systems with multiagent approaches. Information and Software Technology, 53(5), 494–506.Garcia-Fornes, A., Hübner, J., Omicini, A., Rodriguez-Aguilar, J., & Botti, V. (2011). Infrastructures and tools for multiagent systems for the new generation of distributed systems. Engineering Applications of Articial Intelligence, 24(7), 1095–1097.Jennings, N., Faratin, P., Lomuscio, A., Parsons, S., Sierra, C., & Wooldridge, M. (2001). Automated negotiation: prospects, methods and challenges. International Journal of Group Decision and Negotiation, 10(2), 199–215.Jung, Y., Kim, M., Masoumzadeh, A., & Joshi, J. B. (2012). A survey of security issue in multi-agent systems. Artificial Intelligence Review, 37(3), 239–260.Kota, R., Gibbins, N., & Jennings, N. R. (2012). Decentralized approaches for self-adaptation in agent organizations. ACM Transactions on Autonomous and Adaptive Systems (TAAS), 7(1), 1.Kraus, S. (1997). Negotiation and cooperation in multi-agent environments. Artificial Intelligence, 94(1), 79–97.Lin, Y. I., Chou, Y. W., Shiau, J. Y., & Chu, C. H. (2013). Multi-agent negotiation based on price schedules algorithm for distributed collaborative design. Journal of Intelligent Manufacturing, 24(3), 545–557.Luck, M., & McBurney, P. (2008). Computing as interaction: agent and agreement technologies.Luck, M., McBurney, P., Shehory, O., & Willmott, S. (2005). Agent technology: Computing as interaction (A roadmap for agent based computing). AgentLink.Ossowski, S., & Menezes, R. (2006). On coordination and its significance to distributed and multiagent systems. 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Distributed norm management for multi-agent systems. Expert Systems with Applications, 39(5), 5990–5999.Wooldridge, M. (2002). An introduction to multiagent systems. New York: Wiley.Wooldridge, M., & Jennings, N. R. (1995). Intelligent agents: theory and practice. Knowledge Engineering Review, 10(2), 115–152

    Acquired tetanus: clinical and epidemiological characteristics of patients in an university hospital

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    INTRODUCTION: Notwithstanding its substantial decline over the last two decades, acquired tetanus is still a serious health problem in most developing countries. Epidemiological transition is often cited as an explanation for this decline, the increase in vaccination coverage of children being the most obvious cause. Few studies have looked carefully at the current epidemiological patterns of acquired tetanus in developing countries. METHODOLOGY: A descriptive, retrospective (series of cases). An acute care 400 - bed university referral hospital situated in a densely populated and highly urbanized area in Southeastern Brazil (Campinas, SP). Patient records the data-base analysed were from the Epidemiological Surveillance Unit of the hospital. RESULTS: In the 57 month period from January 1989 to March 1996 fifty-three patients were admitted with a diagnosis of acquired tetanus. Fifty patients had clinical confirmation, 3 were otherwise diagnosed. Thirty-two (64%) were male and 18 (36%) female. Fourteen (28%) were from rural areas and 36 (72%) from urban. Mean age was 47.6 years, with a median of 49.5. Of the rural patients, 42.85% were under 30 years and 21.42% were over 50, mean age was 36.21 with a median of 34.5. Fewer urban patients were under 30 (13.88%) than over 50 (58.33%), mean age was 52.19 with a median of 54.5. Trismus was the most frequent (92.0%) clinical sign on admittance, followed by abdominal muscular rigidity (84.0%). Treatment measures were uniform and included tetanus immune globulin, antibiotics, surgical debridement of the wound when feasible, diazepan or curare depending on the intensity of spasms. In the second half of the study period, penicillin was replaced by metronidazol. Overall case fatality rate was 20%, in patients that had to receive curare, it was 60%. Hospitalization exceeded 21 days in 56% (28) of the cases, only 10% (5) had a hospital stay of less than 7 days. CONCLUSION: A high proportion of patients were from rural areas, despite an urbanization rate of more than 90%. In the Campinas region there are two different epidemiological patterns of acquired tetanus: a rural pattern, with a higher proportion of younger patients, determined by an inadequate immunization rate and an urban pattern, similar to that found in industrialized countries, with a higher proportion of older patients. RECOMMENDATIONS: There is an obvious need to immunize older individuals in urban areas and young adults in rural areas. The elimination of acquired tetanus will only be achieved with a wider and more intensive adult vaccination program.INTRODUÇÃO: O número de casos notificados de tétano acidental no Estado de São Paulo sofreu redução. O declínio do número de casos de qualquer doença sempre traz transformações no seu perfil epidemiológico, que devem sempre ser analisadas para aprimorar as medidas preventivas. Assim, foi analisado o perfil clínico e epidemiológico dos casos de tétano internados em hospital universitário de Campinas de 1989 a 1996. MATERIAL E MÉTODO: Estudo descritivo e retrospectivo (série de casos). Todos os pacientes com diagnóstico de tétano de janeiro de 1989 a março de 1996, internados no hospital universitário, foram analisados. RESULTADOS: Catorze (28%) eram da zona rural e 36 (72%) da zona urbana. A idade média foi de 47,6 anos e a mediana de 49,5. Dos pacientes da zona rural, 42,8% tinham até 30 anos e 21,42% tinham mais de 50 anos, sendo a média 36,21 e a mediana 34,5; dos pacientes da zona urbana, 13,9% tinham até 30 anos e 58,3% mais de 50 anos, sendo a média de 52,2 e a mediana de 54,5. A letalidade foi de 20%, mais elevada nos pacientes curarizados (60%). CONCLUSÃO: Na região estudada existem dois padrões epidemiológicos: o rural, com maior número de jovens, refletindo uma vacinação inadequada, e o urbano, semelhante ao dos países desenvolvidos, com predomínio das faixas etárias mais altas

    Effects of formulations containing dimethylaminoethanol (DMAE) acetoamidobenzoate and pidolate on the skin

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    The aim of this study was to analyze the effects of formulations containing DMAE pidolate and DMAE acetoamidobenzoate on the skin. Four areas of five swines were submitted to following treatments during 15 days: C (Control), S (Silicone = 80 % DC*LC Blend®), F1 (DMAE acetoamidobenzoate), F2 (DMAE pidolate). Measures of the thickness of epidermis and stratum corneum, and the density population of fibroblasts and leukocytes in papillary dermis were obtained. We also assessed possible variations in birefringence of dermis collagen bundles. Means of the data was compared using ANOVA followed by the Tukey test. The F1 and F2 groups showed a thicker epidermis than the control group (p < 0.01), but did not demonstrate a significant difference in the number of fibroblasts and leukocytes, as well as in the birefringent areas of collagen bundles, in comparison with the control groups. The DMAE-supplemented formulations enhanced viable epidermis thickness, but did not modify structures related with mechanical properties of the skin.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Analysis of Global Sumoylation Changes Occurring during Keratinocyte Differentiation

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    Sumoylation is a highly dynamic process that plays a role in a multitude of processes ranging from cell cycle progression to mRNA processing and cancer. A previous study from our lab demonstrated that SUMO plays an important role in keratinocyte differentiation. Here we present a new method of tracking the sumoylation state of proteins by creating a stably transfected HaCaT keratinocyte cell line expressing an inducible SNAP-SUMO3 protein. The SNAP-tag allows covalent fluorescent labeling that is denaturation resistant. When combined with two-dimensional gel electrophoresis, the SNAP-tag technology provides direct visualization of sumoylated targets and can be used to follow temporal changes in the global cohort of sumoylated proteins during dynamic processes such as differentiation. HaCaT keratinocyte cells expressing SNAP-SUMO3 displayed normal morphological and biochemical features that are consistent with typical keratinocyte differentiation. SNAP-SUMO3 also localized normally in these cells with a predominantly nuclear signal and some minor cytoplasmic staining, consistent with previous reports for untagged SUMO2/3. During keratinocyte differentiation the total number of proteins modified by SNAP-SUMO3 was highest in basal cells, decreased abruptly after induction of differentiation, and slowly rebounded beginning between 48 and 72 hours as differentiation progressed. However, within this overall trend the pattern of change for individual sumoylated proteins was highly variable with both increases and decreases in amount over time. From these results we conclude that sumoylation of proteins during keratinocyte differentiation is a complex process which likely reflects and contributes to the biochemical changes that drive differentiation
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