A membrane computing simulator of trans-hierarchical antibiotic resistance evolution dynamics in nested ecological compartments (ARES)

In this article, we introduce ARES (Antibiotic Resistance Evolution Simulator) a software device that simulates P-system model scenarios with five types of nested computing membranes oriented to emulate a hierarchy of eco-biological compartments, i.e. a) peripheral ecosystem; b) local environment; c) reservoir of supplies; d) animal host; and e) host's associated bacterial organisms (microbiome). Computational objects emulating molecular entities such as plasmids, antibiotic resistance genes, antimicrobials, and/or other substances can be introduced into this framework and may interact and evolve together with the membranes, according to a set of pre-established rules and specifications. ARES has been implemented as an online server and offers additional tools for storage and model editing and downstream analysisThis work has also been supported by grants BFU2012-39816-C02-01 (co-financed by FEDER funds and the Ministry of Economy and Competitiveness, Spain) to AL and Prometeo/2009/092 (Ministry of Education, Government of Valencia, Spain) and Explora Ciencia y Explora Tecnologia/SAF2013-49788-EXP (Spanish Ministry of Economy and Competitiveness) to AM. IRF is recipient of a "Sara Borrell" postdoctoral fellowship (Ref. CD12/00492) from the Ministry of Economy and Competitiveness (Spain). We are also grateful to the Spanish Network for the Study of Plasmids and Extrachromosomal Elements (REDEEX) for encouraging and funding cooperation among Spanish microbiologists working on the biology of mobile genetic elements (Spanish Ministry of Science and Innovation, reference number BFU2011-14145-E).Campos Frances, M.; Llorens, C.; Sempere Luna, JM.; Futami, R.; Rodríguez, I.; Carrasco, P.; Capilla, R.... (2015). A membrane computing simulator of trans-hierarchical antibiotic resistance evolution dynamics in nested ecological compartments (ARES). Biology Direct. 10(41):1-13. https://doi.org/10.1186/s13062-015-0070-9S1131041Baquero F, Coque TM, Canton R. Counteracting antibiotic resistance: breaking barriers among antibacterial strategies. Expert Opin Ther Targets. 2014;18:851–61.Baquero F, Lanza VF, Canton R, Coque TM. Public health evolutionary biology of antimicrobial resistance: priorities for intervention. Evol Appl. 2014;8:223–39.Baquero F, Coque TM, de la Cruz F. Ecology and evolution as targets: the need for novel eco-evo drugs and strategies to fight antibiotic resistance. Antimicrob Agents Chemother. 2011;55:3649–60.Carlet J, Jarlier V, Harbarth S, Voss A, Goossens H, Pittet D, et al. Ready for a world without antibiotics? The pensieres antibiotic resistance call to action. Antimicrob Resist Infect Control. 2012;1:11.Laxminarayan R, Duse A, Wattal C, Zaidi AK, Wertheim HF, Sumpradit N, et al. Antibiotic resistance-the need for global solutions. Lancet Infect Dis. 2013;13:1057–98.G8-Science-Ministers-Statement. 2013. https://www.gov.uk/government/news/g8-science-ministers-statement .Levy SB, Marshall B. Antibacterial resistance worldwide: causes, challenges and responses. Nat Med. 2004;10:S122–9.Wellington EM, Boxall AB, Cross P, Feil EJ, Gaze WH, Hawkey PM, et al. The role of the natural environment in the emergence of antibiotic resistance in gram-negative bacteria. Lancet Infect Dis. 2013;13:155–65.Marshall BM, Levy SB. Food animals and antimicrobials: impacts on human health. Clin Microbiol Rev. 2011;24:718–33.Marshall BM, Ochieng DJ, Levy SB. Commensals: underappreciated reservoir of antibiotic resistance. Microbe. 2009;4:231–8.Forsberg KJ, Reyes A, Wang B, Selleck EM, Sommer MO, Dantas G. The shared antibiotic resistome of soil bacteria and human pathogens. Science. 2012;337:1107–11.Heuer H, Schmitt H, Smalla K. Antibiotic resistance gene spread due to manure application on agricultural fields. Curr Opin Microbiol. 2011;14:236–43.Teillant A, Laxminarayan R. Economics of Antibiotic Use in U.S. Swine and Poultry Production. Choices. 2015;30:1. 1st Quarter 2015.ANTIBIOTIC RESISTANCE THREATS in the United States. http://www.cdc.gov/drugresistance/threat-report-2013/pdf/ar-threats-2013-508.pdf .Gillings MR. Evolutionary consequences of antibiotic use for the resistome, mobilome and microbial pangenome. Front Microbiol. 2013;4:4.Davies J, Davies D. Origins and evolution of antibiotic resistance. Microbiol Mol Biol Rev. 2010;74:417–33.Palmer AC, Kishony R. Understanding, predicting and manipulating the genotypic evolution of antibiotic resistance. Nat Rev Genet. 2013;14:243–8.Baquero F, Tedim AP, Coque TM. Antibiotic resistance shaping multi-level population biology of bacteria. Front Microbiol. 2013;4:15.Partridge SR. Analysis of antibiotic resistance regions in Gram-negative bacteria. FEMS Microbiol Rev. 2011;35:820–55.Baquero F, Coque TM. Multilevel population genetics in antibiotic resistance. FEMS Microbiol Rev. 2011;35:705–6.Martinez JL, Baquero F, Andersson DI. Predicting antibiotic resistance. Nat Rev Microbiol. 2007;5:958–65.Martinez JL, Baquero F. Emergence and spread of antibiotic resistance: setting a parameter space. Upsala Journal of Medical Sciences. Upsala J Med Sci. 2014, Early Online: 1–10, doi: 10.3109/03009734.2014.901444 ).Baquero F, Nombela C. The microbiome as a human organ. Clin Microbiol Infect. 2012;18 Suppl 4:2–4.Kumsa B, Socolovschi C, Parola P, Rolain JM, Raoult D. Molecular detection of Acinetobacter species in lice and keds of domestic animals in Oromia Regional State. Ethiopia PLoS One. 2012;7:e52377.Ahmad A, Ghosh A, Schal C, Zurek L. Insects in confined swine operations carry a large antibiotic resistant and potentially virulent enterococcal community. BMC Microbiol. 2011;11:23.Graczyk TK, Knight R, Gilman RH, Cranfield MR. The role of non-biting flies in the epidemiology of human infectious diseases. Microbes Infect. 2001;3:231–5.Limoee M, Enayati AA, Khassi K, Salimi M, Ladonni H. Insecticide resistance and synergism of three field-collected strains of the German cockroach Blattella germanica (L.) (Dictyoptera: Blattellidae) from hospitals in Kermanshah, Iran. Trop Biomed. 2011;28:111–8.Salehzadeha A, Tavacolb P, Mahjubc H. Bacterial, fungal and parasitic contamination of cockroaches in public hospitals of Hamadan, Iran. J Vect Borne Dis. 2007;44:105–10.Akinjogunla OJ, Odeyemi AT, Udoinyang EP. Cockroaches (periplaneta americana and blattella germanica): reservoirs of multi drug resistant (MDR) bacteria in Uyo, Akwa Ibom State. Scientific J Biol Sci. 2012;1:19–30.Mideo N, Alizon S, Day T. Linking within- and between-host dynamics in the evolutionary epidemiology of infectious diseases. Trends Ecol Evol. 2008;23:511–7.Gillings MR, Stokes HW. Are humans increasing bacterial evolvability? Trends EcolEvol. 2012;27:346–52.Baquero F. Environmental stress and evolvability in microbial systems. Clin Microbiol Infect. 2009;15 Suppl 1:5–10.Paun G, Rozemberg G, Salomaa A. The Oxford Handbook of Membrane Computing. Oxford, London. Oxford University Press. 2010.Paun G. Membrane Computing. An Introduction. Berlin, Heidelberg. Springer-Verlag GmbH. 2002.Paun G. Computing with membranes. J Comput Syst Sci. 2000;61:108–43.Fontana F, Biancom L, Manca V. P systems and the modeling of biochemical oscillations. Lect Notes Comput Sci. 2006;3850:199–208.Cheruku S, Paun A, Romero-Campero FJ, Perez-Jimenez MJ, Ibarra OH. Simulating FAS-induced apoptosis by using P systems. Prog Nat Sci. 2007;4:424–31.Perez-Jimenez MJ, Romero-Campero FJ. P systems, a new computational modelling tool for systems biology. Transactions on computational systems. Lect N Bioinformat. 2006;Biology VI:176–97.Romero-Campero FJ, Perez-Jimenez MJ. Modelling gene expression control using P systems: The Lac Operon, a case study. Biosystems. 2008;91:438–57.Romero-Campero FJ, Perez-Jimenez MJ. A model of the quorum sensing system in Vibrio fischeri using P systems. Artif Life. 2008;14:95–109.Besozzi D, Cazzaniga P, Pescini D, Mauri G. Modelling metapopulations with stochastic membrane systems. Biosystems. 2008;91:499–514.Cardona M, Colomer MA, Perez-Jimenez MJ, Sanuy D, Margalida A. Modelling ecosystems using P Systems: The Bearded Vulture, a case of study. Lect Notes Comput Sci. 2009;5391:137–56.Cardona M, Colomer MA, Margalida A, Perez-Hurtado I, Perez-Jimenez MJ, Sanuy D. A P system based model of an ecosystem of some scavenger birds. Lect Notes Comput Sci. 2010;5957:182–95.Frisco P, Gheorghe M, Perez-Jimenez M. Applications of Membrane Computing in Systems and Synthetic biology. Cham. Springer International Publishing. 2014.Membrane Computing Community. http://ppage.psystems.eu .P-Lingua. http://www.p-lingua.org/wiki/index.php/Main_Page .Llorens C, Futami R, Covelli L, Dominguez-Escriba L, Viu JM, Tamarit D, et al. The Gypsy Database (GyDB) of mobile genetic elements: release 2.0. Nucleic Acids Res. 2011;39:D70–4.Baquero F. From pieces to patterns: evolutionary engineering in bacterial pathogens. Nat Rev Microbiol. 2004;2:510–8.Java. http://www.java.com .Garcia-Quismondo M, Gutierrez-Escudero R, Martinez-del-Amor MA, Orejuela-Pinedo E, Pérez-Hurtado I. P-Lingua 2.0: a software framework for cell-like P systems. Int J Comput Commun. 2009;IV:234.R programming language. http://www.r-project.org .Maciel A, Sankaranarayanan G, Halic T, Arikatla VS, Lu Z, De S. Surgical model-view-controller simulation software framework for local and collaborative applications. Int J Comput Assist Radiol Surg. 2011;6:457–71.Dethlefsen L, McFall-Ngai M, Relman DA. An ecological and evolutionary perspective on human-microbe mutualism and disease. Nature. 2007;449:811–8.Ley RE, Lozupone CA, Hamady M, Knight R, Gordon JI. Worlds within worlds: evolution of the vertebrate gut microbiota. Nat Rev Microbiol. 2008;6:776–88.Pallen MJ, Wren BW. Bacterial pathogenomics. Nature. 2007;449:835–42.Carrasco P, Perez-Cobas AE, Van de Pol C, Baixeras J, Moya A, Latorre A. Succession of the gut microbiota in the cockroach Blattella germanica. Int Microbiol. 2014;17:99–109

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Predictable cycles in populations of herbivorous insects and their causes

O objetivo geral da tese foi responder por que insetos herbívoros apresentam tendências populacionais cíclicas previsíveis. Os três primeiros capítulos tratam dos mecanismos responsáveis por ciclos de colonização/ extinção de pequena escala local, acontecendo em manchas temporárias de recursos, como cultivos agrícolas de plantas efêmeras. O quarto capítulo indica causas de variação populacional cíclica sazonal, ocorrendo na mesma época do ano e provavelmente em escala regional. Performance alimentar e preferência de oviposição são aspectos da história de vida do indivíduo fundamentais para explicar padrões populacionais em insetos herbívoros. Nós testamos, em laboratório, se o desenvolvimento ontogenético da planta efêmera afeta negativamente a performance do inseto folívoro oligófago P lutella xylostella (Lepidoptera). A despeito da planta hospedeira ( B rassica oleraceae var.capitata) produzir folhas novas ao longo de toda a vida, seu amadurecimento aumentou a mortalidade pré-imaginal do herbívoro. Houve ainda redução na velocidade de desenvolvimento das larvas, no peso das pupas e na fecundidade. Portanto, o desenvolvimento da planta foi acompanhado de uma queda na sua qualidade, de modo que o inseto teve sua performance alimentar diminuída (expressa como taxa reprodutiva líquida (R o) ou como potencial de crescimento populacional (r)). Se não houver outras pressões seletivas mais fortes modulando o comportamento das fêmeas adultas, o resultado da seleção natural poderá ser a preferência de oviposição covariando com a performance ali-mentar das larvas durante o desenvolvimento da planta. Nós sugerimos que insetos oligófagos, que utilizam plantas efêmeras, devem atacar com mais intensidade as fases jovens e tenras do vegetal, embora elas possam conter mais compostos que são tóxicos para outras espécies. Em insetos herbívoros, ciclos populacionais de colonização e extinção em manchas temporárias de plantas são dependentes da migração. A migração geralmente requer mais que uma decisão comportamental e envolve também mudanças morfológicas e fisiológicas no indivíduo. No segundo capítulo, nós testamos se insetos usam diretamente o processo de envelhecimento da planta hospedeira para modular sua atividade migratória entre as manchas de recursos. P . xylostella foi criada em laboratório com plantas de repolho de diferentes idades. Adultos que passaram a fase larval nas plantas tenras de menor idade foram inibidos em sua capacidade migratória. Por outro lado, plantas maduras, especialmente suas folhas novas, estimularam o desenvolvimento de características morfológicas e fisiológicas no adulto que geralmente ocorrem em formas migrantes de insetos. Mudanças químicas ontogenéticas e previsíveis na planta poderiam ser usadas como pistas para o herbívoro prever seu futuro ambiente reprodutivo e modular sua atividade migratória ainda durante a fase larval. No terceiro capítulo, nós investigamos se, em pequenas manchas temporárias de recursos: 1) padrões temporais na abundância local de insetos herbívoros são definidos de baixo para cima na cadeia alimentar, por efeito de mudanças ontogenéticas no tamanho e na qualidade nutricional das plantas; 2) folívoros oligófagos apresentam tendências temporais distintas dos polífagos. Durante o desenvolvimento das plantas hospedeiras (manchas cultiva- das de B. oleraceae var. capitata), larvas da oligófaga P . xylostella e da polífaga T richoplusia ni (Lepidoptera) tiveram tendências paralelas de variação na sua abundância local. Os ciclos paralelos de crescimento e declínio nas populações foram explicados, de modo altamente significativo, pelo crescimento das plantas hospedeiras, pela diminuição na sua qualidade nutricional e pela interação das duas variáveis. A preferência de oviposição das mariposas covariou temporalmente com a performance alimentar das larvas e determinou o paralelismo nas flutuações populacionais das duas espécies. Nós discutimos que, durante o desenvolvi- mento das plantas efêmeras, insetos folívoros monófagos, oligófagos e polífagos devem apre- sentar uma tendência de flutuação populacional comum, generalizada entre eles. Na mancha temporária de plantas, populações locais de predadores e parasitóides provavelmente acompanham a mesma tendência observada no nível trófico abaixo. No quarto capítulo, nós perguntamos se ciclos sazonais, e provavelmente regionais, em populações tropicais da cosmopolita P . xylostella têm relação com a variação sazonal na disponibilidade de recursos. Também foi investigado se fluxos imigratórios previsíveis são a causa proximal do início dos ciclos de crescimento populacional. Durante três anos, plantas preferidas do inseto foram cultivadas continuamente e irrigadas de modo a sempre haver recurso em abundância. Mesmo assim, houve uma tendência populacional sazonal e a hipótese da disponibilidade de recursos não explica o padrão observado. No começo dos ciclos sazonais, o aumento na densidade de adultos precedeu significativamente o aumento na densidade de imaturos. Parece que P . xylostella não sofre diapausa, de modo que fluxos imigratórios foram a causa da fase previsível de crescimento da população. A infestação artificial da área com pupas, durante o outono, quando a população encontrava-se extinta, provocou um ciclo populacional precoce. Portanto, nós assumimos que a época do início dos ciclos é explicada por fatores externos e não necessariamente devida a uma melhoria das condições locais durante o inverno. Hipóteses testáveis também foram sugeridas para explicar por que cada população sazonal foi incapaz de persistir até um novo fluxo imigratório do ano seguinte.The aim of this thesis was to answer why do herbivorous insects show predictable cycles in their populations. In the first three chapters, we dealt with mechanisms behind small- scale cycles in oligophagous and poliphagous species occurring in ephemeral patches of resource, such as agricultural crops. These small-scale cycles of colonization and extinction must be inserted in larger-scale ones. Therefore, in the fourth chapter, we also tried to identify causes of seasonal cycles that occur at roughly the same time of the year and probably in regional scale. Performance and preference are fundamental life history traits to explain patterns in populations of herbivorous insects. Firstly, we asked whether the alimentary performance of the oligophagous P lutella xylostella (Lepidoptera) is negatively affected by the ontogenetic development of its ephemeral host plant ( Brassica oleraceae var. capitata ). Although plants produced new leaves along its life, the pre-imaginal survival of the insect was smaller, and its development was slower in mature than younger plants. The aging of the host plant also reduced the pupal weight and the realized fecundity. As the plant aged, individuals had their alimentary performance decreased (measured as net reproductive rate (R o) or intrinsic rate of increase ( r)). If stronger adaptive pressures do not exist, the result of natural selection should be oviposition preference co-varying with alimentary performance during the plant aging. We expect that monophagous and oligophagous insects would attack mainly younger and tender developmental phases of their ephemeral host plants, even though they can have more compounds that are toxic to others species. Regular cycles of colonization and extinction in ephemeral patches of resource cannot be explained independently of migratory processes. In the second chapter, we tested if insects use the host plant aging to modulate their migratory activity between temporary patches of resources. P xylostella was reared with cabbage of different ages, and adults fed in their larval phase with younger and tender plants seem to be inhibited in their migratory ability. On the other hand, mature plants, especially their new leaves, favored the development of phenotypic traits that are correlated with the migratory activity of insects in general. The low quality and the short persistence of ephemeral mature plant, insufficient for one additional insect generation, should act as a selective pressure favoring migratory ability. Insects would track ontogenetic chemical changes of the host plant to predict their future reproductive environment and to modulate their migratory ability during the pre-imaginal development. Individuals reared on mature plants will be prepared to migrate as soon as they have emerged from the pupa, without losing their short reproductive lifetime searching through the deteriorated resource patch. In the third chapter, we investigated whether in small patches of resources: 1) herbivorous insects have temporal population trends defined by bottom-up forces, related to aging of the host plants; 2) oligophagous and poliphagous herbivores have different population trends. Poliphagous larvae of T richoplusia ni (Lepidoptera) and oligophagous larvae of P . xylostella had parallel population cycles during the development of the plants in cabbage patches. Oviposition had the same decreasing temporal trend that larval performance. Moths were able to detect ontogenetic differences in plant traits, and the selective oviposition behavior shared by the species determined the parallelism in population trends. However, because young plants are smaller and support fewer individuals than mature ones, populations showed cyclic trends, not decreasing. Populations peaked at medium age plants. In fact, cycle trends in both species were fully explained by the plant growth (increase in size or biomass), by its decreasing quality (measured as insect performance or intrinsic rate of increase (r)), and by the interaction between explanatory variables. We discussed that abundance of monophagous, oligophagous and poliphagous insects show a generalized temporal trend during the deve-lopment of their ephemeral host plants. In the plant patch, insect parasitoids and predators probably follow the same temporal pattern than their hosts or preys. In the fourth chapter, we asked if seasonal, and probably also regional, cycles in tropical populations of the cosmopolite P . xylostella have causal relationship with seasonal resource availability. We also investigated if a predictable immigration flow is the proximal cause of each cycle of population growth. We cultivated and irrigated their preferred host plants, making resource abundant along the whole year and during three years. Even so, insects had a seasonal population trend. Population always increased rapidly in winter, but it was already extinct again in early summer. Therefore, seasonal resource availability hypothesis could not explain the population pattern. At the beginning of the seasonal cycles, the increase in adult density preceded significantly in time the increase in immature density. P . xylostella does not diapause, therefore immigration flow was the cause of the predictable population growth. Artificial infestation (immigration) of the area, during autumn, when the population was extinct, started a precocious population cycle. We assumed that the time when cycles begin is determined by external factors, not necessarily by improvement of local conditions during the tropical winter. We suggested mechanistic and testable hypotheses to explain why population was unable to persist until the new immigration flow, in the following year.Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Seasonality in neotropical populations of Plutella xylostella (Lepidoptera): resource availability and migration

The present study aimed to verify (1) whether seasonal increases in neotropical populations of Plutella xylostella are directly provoked by regular influxes of migrants, and (2) whether temporal variation in food availability is the ecological process behind such predictable events. Over 3 years, plants that P. xylostella prefers were cultivated and irrigated in order to provide a continuous and abundant supply of food. Nevertheless, seasonal oscillations in the population of the herbivore still occurred. The hypothesis of seasonal availability of host plants could not explain the population pattern. In April, when the insect was practically extinct from the area, an artificial infestation (immigration) with 10,000 pupae established a precocious population. Therefore, the start of the natural cycles of population growth, during July–August, seems to be due to external factors, rather than an improvement in local conditions for resident individuals. In the beginning of the natural cycles, the increase in the density of adults significantly preceded the increase in immatures. Plutella xylostella does not diapause, and therefore immigration is the proximate cause of the seasonal population increases. Hypotheses about local factors are suggested to explain the decreasing phase of the predictable population cycles

Purification and characterization of trypsin produced by gut bacteria from Anticarsia gemmatalis

Purification of active trypsin in the digestive process of insects is essential for the development of potent protease inhibitors (PIs) as an emerging pest control technology and research into insect adaptations to dietary PIs. An important aspect is the presence of proteolytic microorganisms, which contribute to host nutrition. Here, we purified trypsins produced by bacteria Bacillus cereus, Enterococcus mundtii, Enterococcus gallinarum, and Staphylococcus xylosus isolated from the midgut of Anticarsia gemmatalis. The trypsins had a molecular mass of approximately 25 kDa. The enzymes showed increased activity at 40°C, and they were active at pH values 7.5–10. Aprotinin, bis-benzamidine, and soybean Kunitz inhibitor (SKTI) significantly inhibited trypsin activity. The l-1-tosyl-amido-2-phenylethylchloromethyl ketone (TPCK), pepstatin A, E-64, ethylenediamine tetraacetic acid, and calcium ions did not affect the enzyme activity at the concentrations tested. We infer the purified trypsins do not require calcium ions, by which they differ from the trypsins of other microorganisms and the soluble and insoluble trypsins characterized from A. gemmatalis. These data suggest the existence of different isoforms of trypsin in the velvetbean caterpillar midguts

A desnecessidade do trabalho entre pescadores artesanais

As relações socioculturais e econômicas, entre alguns grupos de pescadores artesanais, não colocam como entes antagônicos trabalho e tempo livre. Do contrário, tais relações celebram aproximações entre saber-fazer pesqueiro, lazer e vida, formando e conformando um todo societário. Inseridos nesse quadro, estão os pescadores artesanais do mar-de-fora da praia de Suape, no município do Cabo de Santo Agostinho, litoral sul de Pernambuco, distante 50 km de Recife. Este artigo busca desvelar a mencionada moral do trabalho e do tempo livre no fazer cotidiano de pescadores dessa Praia, com base na pesquisa etnográfica e na história de vida de 13 pescadores. No geral, identificou-se que há uma moral do trabalho que se confunde à moral do tempo livre, pois o cerceamento de uma delas representa limites à outra. Assim, para esses homens, definir o que é um ser liberto ou cativo liga-se ao encontro indissociável, em termos práticos e simbólicos, entre as referidas morais, o que é essencial para classificar o fazer-se pescador artesanal em seu sentido pleno fundamentado na desnecessidade do trabalho

Long-term carriage and rapid transmission of extended spectrum beta-lactamase-producing E. coli within a flock of Mallards in the absence of antibiotic selection

Wild birds have been suggested as transmitters and reservoirs for antibiotic resistant bacteria. We performed an experimental study investigating carriage time and interindividual transmission of extended spectrum beta‐lactamase‐ (ESBL‐)producing Escherichia coli in Mallards (Anas platyrhynchos) to assess if the birds carry the bacteria long enough to transfer them geographically during migration. Mallards were inoculated intraoesophageally with four different strains of ESBL‐producing E. coli and kept together in a flock. The ESBL‐strains belonged to sequence types previously shown to spread between birds and humans. Culturing from faecal samples showed presence of ESBL‐producing E. coli the entire 29 day experimental period. An extensive and rapid transmission of the different ESBL‐strains between individuals (including non‐inoculated controls) was observed. In necropsy samples, we detected ESBL‐strains in the cecum even in faeces‐negative birds, indicating that this part of the intestine could function as a reservoir of resistant bacteria. We demonstrate that birds can carry ESBL‐producing E. coli for long enough times to travel far during migration and the extensive interindividual transmission suggests spread between individuals in a dense bird population as a mechanism that allow persistence of resistant bacteria