Impact of polymicrobial biofilms in catheter-associated urinary tract infections

Recent reports have demonstrated that most biofilms involved in catheter-associated urinary tract infections are polymicrobial communities, with pathogenic microorganisms (e.g. Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and uncommon microorganisms (e.g. Delftia tsuruhatensis, Achromobacter xylosoxidans) frequently co-inhabiting the same urinary catheter. However, little is known about the interactions that occur between different microorganisms and how they impact biofilm formation and infection outcome. This lack of knowledge affects CAUTIs management as uncommon bacteria action can, for instance, influence the rate at which pathogens adhere and grow, as well as affect the overall biofilm resistance to antibiotics. Another relevant aspect is the understanding of factors that drive a single pathogenic bacterium to become prevalent in a polymicrobial community and subsequently cause infection. In this review, a general overview about the IMDs-associated biofilm infections is provided, with an emphasis on the pathophysiology and the microbiome composition of CAUTIs. Based on the available literature, it is clear that more research about the microbiome interaction, mechanisms of biofilm formation and of antimicrobial tolerance of the polymicrobial consortium are required to better understand and treat these infections.This work was financially supported by: Project POCI-010145-FEDER-006939 – Laboratory for Process Engineering, Environment, Biotechnology and Energy – LEPABE funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) – and by national funds through FCT – Fundacao para a Ci^encia e a Tecnologia; Project “DNAmimics” [PIC/IC/82815/2007]; PhD fellowships [SFRH/BD/82663/2011].info:eu-repo/semantics/publishedVersio

Influence of the fixation/permeabilization step on peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) for the detection of bacteria

Fluorescence in situ Hybridization (FISH) is a versatile, widespread and widely- used technique in microbiology. The first step of FISHfixation/permeabilizationis crucial to the outcome of the method. This work aimed to systematically evaluate fixation/permeabilization protocols employing ethanol, triton X-100 and lysozyme in conjugation with paraformaldehyde for Peptide Nucleic Acid (PNA)-FISH. Response surface methodology was used to optimize these protocols for Gram-negative (Escherichia coli and Pseudomonas fluorescens) and Gram-positive species (Listeria innocua, Staphylococcus epidermidis and Bacillus cereus). In general, the optimal PNA-FISH fluorescent outcome in Gram-positive bacteria was obtained employing harsher permeabilization conditions when compared to Gram-negative optimal protocols. The observed differences arise from the intrinsic cell envelope properties of each species and the ability of the fixation/permeabilization compounds to effectively increase the permeability of these structures while maintaining structural integrity. Ultimately, the combination of paraformaldehyde and ethanol proved to have significantly superior performance for all tested bacteria, especially for Gram-positive species (p<0.05).This work was the result of the projects: POCI-01-0145-FEDER-006939 (Laboratory for Process Engineering, Environment, Biotechnology and Energy - UID/EQU/00511/2013) and POCI-010145-FEDER-006684 (Centerof Biological Engineering - UID/EQU/00511/2013)funded by the European Regional Development Fund (ERDF), through COMPETE2020- Programa Operacional Competitividade e Internacionalização (POCI) and by national funds, throughFCT - Fundação para a Ciênciae a Tecnologia. NORTE-01-0145-FEDER000005 - LEPABE-2-ECO-INNOVATIONand NORTE-01-0145-FEDER-000004- BioTecNorte operation,supported by North Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 PartnershipAgreement, throughthe EuropeanRegional Development Fund (ERDF). PhD Fellowship SFRH/BDE/51910/2012 supported by national funds through FCT - Fundação para a Ciênciae a Tecnologia. ENMed/0003/2014 NanoDiaBac and PTDC/DTP-PIC/4562/2014 Coded-FISHfunded by national funds throughFCT - Fundac ¸ão para a Ciênciae a Tecnologia. Rui Rocha works for and receives salary from Biomode S.A, a companythat developsand commercializes in vitro diagnostickits for microorganism detection, using PNA-FISHtechnology. Also, Carina Almeida and Nuno F. Azevedo are foundersand shareholders of Biomode SA. The specific roles of these authors are articulated in the ‘author contributions’ section. The funders had no role in study design, data collectionand analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

New insights on biofilm antimicrobial strategies

Over the last few decades, the study of microbial biofilms has been gaining interest among the scientific community [...]info:eu-repo/semantics/publishedVersio

Raça Sorraia: primeiro nascimento mundial por transferência embrionária

info:eu-repo/semantics/publishedVersio

In-situ co-amorphization of olanzapine in pellets

Poster presented at the 13th PBP World Meeting on Pharmaceutics, Biopharmaceutics and Pharmaceutical Technology. Rotterdam, The Netherlands, 28-31 March 2022N/

Argamassas fotocatalíticas: influência da composição na resistência mecânica e na capacidade de auto-limpeza

O presente artigo apresentam-se resultados relativos ao estudo conjunto de diversos parâmetros na resistência mecânica e na capacidade de auto-limpeza de argamassas fotocatalíticas. Os resultados obtidos mostram que a fim de manter a mesma consistência em todas as argamassas se torna necessário aumentar a razão w/b com a percentagem de TiO2 o que se traduz numa redução acentuada da resistência mecânica das argamassas. Os resultados mostram ainda que que as composições com 2% de TiO2 são as que apresentam uma maior capacidade de auto-limpeza

Interaction between atypical microorganisms and E. coli in catheter-associated urinary tract biofilms

Most biofilms involved in catheter-associated urinary tract infections (CAUTIs) are polymicrobial, with disease causing (eg Escherichia coli) and atypical microorganisms (eg Delftia tsuruhatensis) frequently inhabiting the same catheter. Nevertheless, there is a lack of knowledge about the role of atypical microorganisms. Here, single and dual-species biofilms consisting of E. coli and atypical bacteria (D. tsuruhatensis and Achromobacter xylosoxidans), were evaluated. All species were good biofilm producers (Log 5.84–7.25 CFU cm−2 at 192 h) in artificial urine. The ability of atypical species to form a biofilm appeared to be hampered by the presence of E. coli. Additionally, when E. coli was added to a pre-formed biofilm of the atypical species, it seemed to take advantage of the first colonizers to accelerate adhesion, even when added at lower concentrations. The results suggest a greater ability of E. coli to form biofilms in conditions mimicking the CAUTIs, whatever the pre-existing microbiota and the inoculum concentration.This work was supported by the Portuguese Science Foundation (FCT), DNA mimics Research Project [Ref. PIC/IC/82815/2007] from the FCT and MCTES; PhD Fellowship [SFRH/BD/82663/2011]; and Postdoctoral Fellowship [SFRH/BPD/74480/2010]. The authors would like to thank to M. Fenice M and A. Steinbuchel for kindly providing the Delftia tsuruhatensis BM90 and Achromobacter xylosoxidans B3 species, respectively

Impact of Delftia tsuruhatensis and Achromobacter xylosoxidans on Escherichia coli dual-species biofilms treated with antibiotic agents

Recently it was demonstrated that for urinary tract infections species with a lower or unproven pathogenic potential, such as Delftia tsuruhatensis and Achromobacter xylosoxidans, might interact with conventional pathogenic agents such as Escherichia coli. Here, single- and dual-species biofilms of these microorganisms were characterized in terms of microbial composition over time, the average fitness of E. coli, the spatial organization and the biofilm antimicrobial profile. The results revealed a positive impact of these species on the fitness of E. coli and a greater tolerance to the antibiotic agents. In dual-species biofilms exposed to antibiotics, E. coli was able to dominate the microbial consortia in spite of being the most sensitive strain. This is the first study demonstrating the protective effect of less common species over E. coli under adverse conditions imposed by the use of antibiotic agents.This work was financially supported by the FCT/MEC with national funds and when applicable co-funded by FEDER in the scope of the P2020 Partnership Agreement [Project UID/ EQU/00511/2013-LEPABE]; FEDER funds through the Operational Programme for Competitiveness Factors – COMPETE, O Novo Norte–North Portugal Regional Operational Programme – ON2 and National Funds through Foundation for Science and Technology – FCT [Project NORTE-07-0124- FEDER-000025–RL2_ Environment&Health and Project ‘DNAmimics’ PIC/IC/82815/2007]; PhD fellowship [SFRH/ BD/82663/2011]; and postdoctoral fellowship [SFRH/ BPD/74480/2010]

A Elipse da Incerteza : do sentido do (ba)bélico em Gravity's Rainbow, de Thomas Pynchon

Num cenário de guerra, o bélico gera o babélico, a falta de sentido. Aqui reside a lógica de Gravity's Rainbow, pois o seu núcleo é uma ausência centrípeta. Esta angústia epistemológica implica a fragmentação ontológica dos mundos de Gravity's Rainbow. Tyrone Slothrop e a Zona, respectivamente os micro e macrocosmos de Gravity's Rainbow, são as representações por excelência desta disseminação da unidade. A incerteza dos seus contornos revela-os como espaços coerentes: a sua integridade reside na sua verosímil desintegração. Expoente máximo do Pós-Modernismo, a obra-prima de Thomas Pynchon anula-se como texto maior de sentido, como qualquer metanarrativa. Em Gravity's Rainbow, quer a ciência quer a história serão refundidas, e o leitor, epistemologicamente abalado, reformular-se-á ontologicamente. Condicionado a descondicionar-se, o leitor terá de conviver com a sua "Capacidade Negativa", admitindo a incerteza - talvez não ache elíptico