Caracterização molecular da resistência aos carbapenêmicos e disseminação de amostras clínicas e ambientais de Acinetobacter baumannii multirresistentes produtoras de biofilme: caracterização molecular de Acinetobacter baumannii

The emergence of infections associated with new antimicrobial-resistant Acinetobacter baumannii genotypes represents a major challenge. Thus, the detection and knowledge of its epidemiological and molecular characteristics have fundamental importance for the development of treatment, prevention, and control strategies. This study aimed to determinate the diversity of resistance mechanisms, to evaluate the biofilm production through phenotypic techniques and scanning electron microscopy (SEM), and to investigate the clonal dissemination and the predominant Sequence Types (STs) in multiresistant strains of A. baumannii from clinical (tracheal aspirate, n=17) and environmental (surface, n=6) origin, isolated at the Adult Intensive Care Unit (ICU) of the Clinical Hospital of the Federal University of Uberlândia (HC-UFU). Additionally, one clinical (clone A) and one environmental (clone H) strain had their complete genome sequenced with partial analysis of their resistomes. All strains were submitted to polymerase chain reaction (PCR) for the detection of ISAba/ genes and their association or not with oxacillinases (OXA-51 and OXA-23), genes of outer membrane proteins (OMPs) carO and pme33-36, and genes encoding AdeABC (adeB), AdeFGH (adeG) and AdeIJK (adeJ) efflux pumps. Confirmation of tigecycline and carbapenem resistance was done by the Etest®. Most of the strains were characterized as extensively drug-resistant (XDR) with very high minimal inhibitory concentrations (MICs) for tigecycline and carbapenems. The association of ISAba//OXA-51, ISAba//OXA-23 and the presences of carO and pme 33-36 were observed in 91.3%, 52.2%, 82.6% and 100% of the strains, respectively. The genes adeB, adeG and adeJ were observed in all strains analyzed. The consumption of Imipenem, Meropenem, Tigecycline and Polymyxin B/Colistin (DDD/1000 patients-day) was also evaluated in the period from January 2011 to December 2012. Changes in the consumption of these antimicrobials were observed during the period investigated. According to clonal profiles obtained by the Pulsed Field Gel Electrophoresis (PFGE) technique, ten A. baumannii strains were selected for analysis by real-time PCR (qPCR), phenotypic analysis of biofilm production and Multilocus Sequence Typing (MLST). Only adeB gene was considered hyper-expressed. MLST results demonstrated polyclonal dissemination, identifying eight STs and five clonal complexes (CCs), with predominance of CCs 113, 229 and 109. All A. baumannii evaluated strains adhered to the unmodified polystyrene surface and produced biofilm, with no significant difference between clinical and environmental isolates. SEM images confirmed the ability of adhesion and the presence of a visible extracellular matrix. Our study found a wide variety of clonal complexes related to XDR A. baumannii carrying the b/aOXA_23 gene frequently associated with ISAba/ (Tn2008) as the main mechanism of carbapenems resistance, in addition to the over expression of the AdeABC efflux pump. The understanding of the mechanisms of resistance and the pathogenic potential of this microorganism helps to explain its persistence in the hospital environment and can provide tools to improve the treatment of serious infections, as well as, the measures of control and prevention of these infections.Tese (Doutorado)A emergência de infecções associadas a novos genótipos de Acinetobacter baumannii resistente aos antimicrobianos reflete um desafio de grandes proporções. Assim, a detecção e o conhecimento de suas características, tanto epidemiológicas quanto moleculares, é de fundamental importância para o desenvolvimento de estratégias de tratamento, prevenção e controle. Este trabalho teve como objetivos determinar a diversidade de mecanismos de resistência, avaliar a produção de biofilme através de técnicas fenotípicas e microscopia eletrônica de varredura (MEV) e investigar a disseminação clonal e os Sequence Types (STs) predominantes em amostras multirresistentes de A. baumannii de origem clínica (aspirado traqueal, n=17) e ambiental (superfície, n=6), isoladas na Unidade de Terapia Intensiva (UTI) de Adultos do Hospital de Clínicas da Universidade Federal de Uberlândia (HC-UFU). Adicionalmente, uma amostra clínica (clone A) e uma ambiental (clone H) tiveram seu genoma completo sequenciado com análise parcial de seus resistomas. Todas as amostras foram submetidas à reação em cadeia da polimerase (PCR) para detecção dos genes ISAba/ e sua associação ou não com as oxacilinases (OXA-51 e OXA-23), genes das proteínas de membrana externa (PME) carO e pme33-36 e genes que codificam a expressão das bombas de efluxo AdeABC (adeB), AdeFGH (adeG) e AdeIJK (adeJ). A confirmação da resistência à tigeciclina e aos carbapenêmicos foi feita pelo método do Etest®. A maioria das amostras foi caracterizada como extensivamente resistente (XDR) com concentrações inibitórias mínimas (CIMs) muito elevadas para tigeciclina e carbapenêmicos. A associação ISAba//OXA-51, ISAba//OXA-23 e a presença de carO e pme33-36 foram observadas em 91,3%, 52,2%, 82,6% e 100% das amostras, respectivamente. Quanto aos genes adeB, adeG e adeJ, sua presença foi constatada em todas as amostras analisadas. Avaliou-se também o consumo de Imipenem, Meropenem, Tigeciclina e Polimixina B/Colistina (DDD/1000 pacientes-dia), no período de janeiro de 2011 a dezembro de 2012. Observaram-se variações no consumo desses antimicrobianos, durante o período investigado. De acordo com os perfis clonais obtidos através da técnica de Pulsed Field Gel Electrophoresis (PFGE) foram selecionadas dez amostras de A. baumannii para as análises por PCR em tempo real (qPCR), análise fenotípica da produção de biofilme e Multilocus Sequence Typing (MLST). Após avaliação por qPCR, somente o gene adeB foi considerado hiperexpresso. Os resultados do MLST demonstraram disseminação policlonal, identificando oito STs e cinco complexos clonais (CCs), com predominância dos CCs 113, 229 e 109. Todas as amostras de A. baumannii avaliadas aderiram à superfície de poliestireno não modificada e produziram biofilme, sem diferença significativa entre isolados clínicos e ambientais. As imagens de MEV confirmaram a capacidade de adesão e a presença de matriz extracelular visível. Nosso estudo encontrou uma ampla variedade de complexos clonais relacionados com A. baumannii XDR carreando o gene blaOXA-23 frequentemente associado com ISAba/ (Tn2008) como o principal mecanismo de resistência aos carbapenêmicos, além da hiperexpressão da bomba de efluxo AdeABC. A compreensão dos mecanismos de resistência e do potencial patogênico deste microorganismo ajuda a explicar sua persistência no ambiente hospitalar e pode fornecer ferramentas para melhorar o tratamento de infecções graves, assim como para aprimorar as medidas de controle e prevenção dessas infecções

Domesticated Dogs’ (Canis familiaris) Response to Dishonest Human Points

We would like to thank Sherry McClurkin, Robin Reutten, and Chelsea Taglang for their assistance in data collection and participant recruitment for this study. Correspondence concerning this article should be addressed to Shannon M.A. Kundey at Hood College, Department of Psychology, 401 Rosemont Avenue, Room ROS 27, Frederick, MD 21701, U.S.A. ([email protected]).Pointing is a conventional communicative gesture used by humans to direct others’ attention to an environmental feature. Several researchers have argued that pointing becomes so ingrained for humans from a young age that children often have difficulty interpreting the gesture in a novel way. Recent research suggests domestic dogs are also sensitive to human gestures (including points) and proficient in recognizing and acting on humans’ visual attention. We explored the role of pointing in dogs’ choice behavior and whether dogs, like human children, have difficulty interpreting the gesture novelly. In Experiment 1, we explored whether dogs would differentially follow a static human point when it was administered by a familiar or unfamiliar individual and that individual indicated or failed to indicate the correct location of a food reward. The results indicated dogs chose the container specified by the demonstrators’ point in the honest and dishonest condition. Demonstrator familiarity did not alter performance. In Experiment 2, we compared dogs’ propensity to follow a static point versus other cues (momentary point, standing location) when the cue never indicated the correct location of a food reward, which was either visible or hidden during choice. The results suggested dogs did not inhibit their approach to a location indicated by a deceptive static point even when the location of a reward was visibly available during choice. However, dogs used a deceptive momentary point or standing location to locate food in both visible and hidden trials. In Experiment 3, we explored if dogs could overcome their tendency to follow a deceptive static point. These results indicated dogs learned to inhibit their approach to a deceptive static point when the reward was visible during choice. However, when information about the reward’s location was later hidden, dogs reverted to following the demonstrator’s static point

Biofilm formation of Brazilian meticillin-resistant Staphylococcus aureus strains: prevalence of biofilm determinants and clonal profiles

Biofilms plays an important role in medical-device-related infections. This study aimed to determine the factors that influence adherence and biofilm production, as well as the relationship between strong biofilm production and genetic determinants in clinical isolates of meticillin-resistant Staphylococcus aureus (MRSA). Fifteen strains carrying different chromosomal cassettes recovered from hospitalized patients were selected; five SCCmecII, five SCCmecIII and five SCCmecIV. The SCCmec type, agr group and the presence of the virulence genes (bbp, clfA, icaA, icaD, fnbB, bap, sasC and IS256) were assessed by PCR. PFGE and multilocus sequence typing (MLST) techniques were also performed. The initial adhesion and biofilm formation were examined by quantitative assays. The surface tension and hydrophobicity of the strains were measured by the contact angle technique to evaluate the association between these parameters and adhesion ability. SCCmecIII and IV strains were less hydrophilic, with a high value for the electron acceptor parameter and higher adhesion in comparison with SCCmecII strains. Only SCCmecIII strains could be characterized as strong biofilm producers. The PFGE showed five major pulsotypes (AE); however, biofilm production was related to the dissemination of one specific PFGE clone (C) belonging to MLST ST239 (Brazilian epidemic clonal complex). The genes agrI, fnbB and IS256 in SCCmecIII strains were considered as genetic determinants associated with strong biofilm-formation by an ica-independent biofilm pathway. This study contributes to the understanding of biofilm production as an aggravating factor potentially involved in the persistence and severity of infections caused by multidrug-resistant MRSA belonging to this genotype.We thank FAPEMIG (Fundação de Amparo à Pesquisa de Minas Gerais, proceeding APQ 01398-11) and CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, PDSE proceeding 8952/11-6) for the financial support and scholarships. We also thank Dr Teruyo Ito, Juntendo University, Japan, and Dr Elsa Masae Mamizuka, Universidade de São Paulo, Brazil, for kindly providing the control strains used in this study.info:eu-repo/semantics/publishedVersio

The wide-field, multiplexed, spectroscopic facility WEAVE : survey design, overview, and simulated implementation

Funding for the WEAVE facility has been provided by UKRI STFC, the University of Oxford, NOVA, NWO, Instituto de Astrofísica de Canarias (IAC), the Isaac Newton Group partners (STFC, NWO, and Spain, led by the IAC), INAF, CNRS-INSU, the Observatoire de Paris, Région Île-de-France, CONCYT through INAOE, Konkoly Observatory (CSFK), Max-Planck-Institut für Astronomie (MPIA Heidelberg), Lund University, the Leibniz Institute for Astrophysics Potsdam (AIP), the Swedish Research Council, the European Commission, and the University of Pennsylvania.WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366-959 nm at R ∼ 5000, or two shorter ranges at R ∼ 20,000. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for ∼ 3 million stars and detailed abundances for ∼ 1.5 million brighter field and open-cluster stars; (ii) survey ∼ 0.4 million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey  ∼ 400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in z 1 million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at z > 2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator.PostprintPeer reviewe

The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation

WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366$-$959\,nm at $R\sim5000$, or two shorter ranges at $R\sim20\,000$. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for $\sim$3 million stars and detailed abundances for $\sim1.5$ million brighter field and open-cluster stars; (ii) survey $\sim0.4$ million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey $\sim400$ neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in $z<0.5$ cluster galaxies; (vi) survey stellar populations and kinematics in $\sim25\,000$ field galaxies at $0.3\lesssim z \lesssim 0.7$; (vii) study the cosmic evolution of accretion and star formation using $>1$ million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at $z>2$. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator.Comment: 41 pages, 27 figures, accepted for publication by MNRA

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation

WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366−959\,nm at R∼5000, or two shorter ranges at R∼20000. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for ∼3 million stars and detailed abundances for ∼1.5 million brighter field and open-cluster stars; (ii) survey ∼0.4 million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey ∼400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in z1 million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at z>2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator