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Ventilator-associated pneumonia (VAP) is an unresolved problem in nosocomial settings, remaining consistently associated with a lack of treatment, high mortality, and prolonged hospital stay in mechanically ventilated patients. The endotracheal tube (ETT) is the major culprit for VAP development owing to its early surface microbial colonization and biofilm formation by multiple pathogens, both critical events for VAP pathogenesis and relapses. To combat this matter, gradual research on antimicrobial ETT surface coating/modification approaches has been made. This review provides an overview of the relevance and implications of the ETT bioburden for VAP pathogenesis and how technological research on antimicrobial materials for ETTs has evolved. Firstly, certain main VAP attributes (definition/categorization; outcomes; economic impact) were outlined, highlighting the issues in defining/diagnosing VAP that often difficult VAP early- and late-onset differentiation, and that generate misinterpretations in VAP surveillance and discrepant outcomes. The central role of the ETT microbial colonization and subsequent biofilm formation as fundamental contributors to VAP pathogenesis was then underscored, in parallel with the uncovering of the polymicrobial ecosystem of VAP-related infections. Secondly, the latest technological developments (reported since 2002) on materials able to endow the ETT surface with active antimicrobial and/or passive antifouling properties were annotated, being further subject to critical scrutiny concerning their potentialities and/or constraints in reducing ETT bioburden and the risk of VAP while retaining/improving the safety of use. Taking those gaps/challenges into consideration, we discussed potential avenues that may assist upcoming advances in the field to tackle VAP rampant rates and improve patient care. Statement of significance : The use of the endotracheal tube (ETT) in patients requiring mechanical ventilation is associated with the development of ventilator-associated pneumonia (VAP). Its rapid surface colonization and biofilm formation are critical events for VAP pathogenesis and relapses. This review provides a comprehensive overview on the relevance/implications of the ETT biofilm in VAP, and on how research on antimicrobial ETT surface coating/modification technology has evolved over the last two decades. Despite significant technological advances, the limited number of gathered reports (46), highlights difficulty in overcoming certain hurdles associated with VAP (e.g., persistent colonization/biofilm formation; mechanical ventilation duration; hospital length of stay; VAP occurrence), which makes this an evolving, complex, and challenging matter. Challenges and opportunities in the field are discussed., This research was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020–Programa Operacional Regional do Norte. The authors also acknowledge the support, through the Programa Operacional Competitividade e Internacionalização (COMPETE2020) and by national funds, through FCT for the POLY-PrevEnTT project (PTDC/BTMSAL/29841/2017- POCI-01-0145-FEDER029841) and the Ph.D. Grant of Tânia Grainha (SFRH/BD/136544/2018)., info:eu-repo/semantics/publishedVersion

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fgene.2022.883199/ full#supplementary-material, Cystic fibrosis (CF) is a common heritable genetic disorder caused by a defect in the cystic fibrosis conductance regulator gene, resulting in several complications in the human body (Kreda et al., 2012). So far, the pathological changes in the lungs are best studied due to the high mortality rates linked to poor lung function and the recurrent development of severe biofilm-related infections (Flume et al., 2009; Ciofu et al., 2015). Staphylococcus aureus and Pseudomonas aeruginosa are the most prevalent pathogens that colonize structurally abnormal airways such as those diagnosed with CF and other chronic obstructive lung diseases (Lyczak et al., 2002; Hubert et al., 2013). Although these bacteria seem to succeed with one another, CF patients acquire coinciding P. aeruginosa and S. aureus pulmonary infections, being co-infection usually associated with decreased lung function and increased frequency of pulmonary exacerbations (Limoli et al., 2016). Furthermore, P. aeruginosa and S. aureus pathogens adopt a biofilm mode of growth, which contributes to high tolerance to antibiotic treatment (Schobert and Jahn, 2010) and the recalcitrant nature of these chronic co-infections (Burmølle et al., 2006; Lopes et al., 2012), leading to significant patient morbidity and mortality (Cox et al., 2010). Interactions between P. aeruginosa and S. aureus have been widely studied, and it is commonly admitted that P. aeruginosa outcompetes S. aureus, perhaps outcompeting S. aureus for limited nutrients (Mashburn et al., 2005) or producing antistaphylococcal compounds (DeLeon et al., 2014; Fugère et al., 2014), having S. aureus a minimal contribution to the overall course of the CF-associated biofilm infections (Bragonzi et al., 2012; Filkins et al., 2015). However, P. aeruginosa and S. aureus have been identified in the same lobe of CF lungs (Hogan et al., 2016; Wakeman et al., 2016) and are frequently diagnosed (Limoli et al., 2016; Zolin et al., 2019) as co-infecting species in CF patients. Moreover, P. aeruginosa strains isolated from early infection outcompete S. aureus, while strains isolated from chronic infection are less aggressive and can be co-cultivated with S. aureus (Frydenlund Michelsen et al., 2016; Limoli et al., 2017), suggesting that these pathogens can interact in vivo. In a previous study, we showed that S. aureus can grow and coexist with P. aeruginosa under dualspecies biofilm conditions (Magalhães et al., 2021). Following up on these findings, and acknowledging that the molecular mechanisms behind these interactions are largely unknown, the purpose of the present study was, therefore, to identify the major transcriptomic features of P. aeruginosaS. aureus dual-species biofilms, using high-throughput RNA-sequencing (RNA-seq). Herein, we described the full transcriptome of P. aeruginosa and S. aureus single- and dual-species biofilms and used a data analysis approach based on direct and functional gene interactions, namely gene set enrichment. These results will be invaluable for future functional studies involving P. aeruginosaS. aureus interactions., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit and the BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020–Programa Operacional Regional do Norte. The authors also acknowledge the support, through the Programa Operacional Competitividade e Internacionalização (COMPETE 2020) and by national funds, through FCT, of the PhD Grant of APM (SFRH/BD/132165/2017)., info:eu-repo/semantics/publishedVersion

This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The authors also acknowledge the support, through the Programa Operacional Competitividade e Internacionalização (COMPETE2020) and by national funds, through the Portuguese Foundation for Science and Technology (FCT), of the POLY-PrevEnTT project (PTDC/BTM-SAL/29841/2017-POCI-01-0145-FEDER-029841)., Ventilator-associated pneumonia (VAP) is currently one of the top five most common nosocomial infections and it has been associated with prolonged hospitalization and high morbidity and mortality rates [1]. The use of an endotracheal tube (EET) constitutes the major risk factor for the development of this condition, since it is the airway access point for microorganisms. Indeed, microorganisms migration along and within the inside of the EET results in a so-called biofilm which, combined with a network of secretions, will be ultimately leaked down to lungs [2]. Biofilm formation is a crucial step in the pathogenesis of VAP, as microbial cells within a biofilm encase themselves in a self-produced matrix of extracellular polymeric substances, conferring them protection against both antimicrobial treatments and the host immune system. Furthermore, the polymicrobial nature of biofilms formed on the surfaces of ETT has been increasingly addressed [3]. This study aimed to design a wide-spectrum antimicrobial coating to impart endotracheal tubes with the ability to prevent the adhesion and subsequent biofilm formation of several microorganisms commonly associated to VAP, without compromising the viability of lung cells. For that, ciprofloxacin (CIP) and chlorhexidine (CHX), two compounds with different action spectra, were co-immobilized on polyvinyl chloride (PVC) surfaces to obtain a dual-drug release antimicrobial coating. Immobilization was performed using a one-step polydopamine (pDA)-based approach, in which PVC substrata were simply immersed on a solution of dopamine dissolved together with CHX and/or CIP, allowing their incorporation throughout the full thickness of the pDA film. The antimicrobial performance of modified surfaces was evaluated against 5 bacterial species (Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus and Staphylococcus epidermidis) and 1 yeast species (Candida albicans) as individual, dual and triple consortia. Regarding the single-species colonisation of PVC surfaces, results showed that after 24 h of exposure, co-immobilization of CHX and CIP caused a significant reduction (more than 4 Log) in the number of bacterial cells adhered to the surfaces, while being less efficient against the adhesion of C. albicans (0.5 Log). It is worth mentioning that the combination of CIP and CHX in the proposed coating resulted both in a synergic effect against P. aeruginosa, A. baumannii and C. albicans and in a facilitative effect against all tested species. Coatings were also tested against the dual adhesion of P. aeruginosa in consortium with all tested species. In general, results showed that the antimicrobial effect observed for each species was not compromised by the presence of any other species. Inhibition of C. albicans was actually more effective (approximately 2 Log reduction) when combined with P. aeruginosa. When the antimicrobial coating was exposed to a triple consortium comprised by P. aeruginosa, S. aureus and C. albicans, its antimicrobial effect against bacterial species was not compromised and it was able to inhibit the adhesion of yeast by about 1 Log. In terms of biocompatibility, the amount of CHX and CIP released from the surfaces did not compromise the growth of lung epithelial cells. Surfaces functionalization with CIP and/or CHX was confirmed by SEM, AFM and contact angle measurements. In conclusion, the combination of CIP and CHX, using dopamine chemistry, results in a coating with antimicrobial activity towards a wide spectrum of microorganisms commonly associated to VAP. Therefore, this approach holds great potential to be applied in EET, proving to be important in the fight against VAP. References [1] D. Nora, P. Póvoa, Antibiotic consumption and ventilator-associated pneumonia rates, some parallelism but some discrepancies, Ann. Transl. Med. (2017). doi:10.21037/atm.2017.09.16. [2] A. Rouzé, I. Martin-Loeches, S. Nseir, Airway Devices in Ventilator-Associated Pneumonia Pathogenesis and Prevention, Clin. Chest Med. (2018). doi:10.1016/j.ccm.2018.08.001. [3] M.E. Rodrigues, S.P. Lopes, C.R. Pereira, N.F. Azevedo, A. Lourenço, M. Henriques, M.O. Pereira, Polymicrobial ventilator-associated pneumonia: Fighting in vitro Candida albicans-pseudomonas aeruginosa biofilms with antifungal-antibacterial combination therapy, PLoS One. 12 (2017). doi:10.1371/journal.pone.0170433., info:eu-repo/semantics/publishedVersion

Aim: To investigate the role of pre-established Staphylococcus aureus on Pseudomonas aeruginosa adaptation and antibiotic tolerance. Materials & methods: Bacteria were cultured mimicking the sequential pattern of lung colonization and exposure to ciprofloxacin. Results: In the absence of ciprofloxacin exposure, S. aureus and P. aeruginosa coexisted supported by the physicochemical characteristics of the artificial sputum medium. S. aureus had no role in P. aeruginosa tolerance against ciprofloxacin and did not select P. aeruginosa small-colony variants during antibiotic treatment. rhlR and psqE were downregulated after the contact with S. aureus indicating that P. aeruginosa attenuated its virulence potential. Conclusion: P. aeruginosa and S. aureus can cohabit in cystic fibrosis airway environment for long-term without significant impact on P. aeruginosa adaptation and antibiotic tolerance., This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit. The authors also acknowledge COMPETE2020 and FCT for the project POCI-01-0145-FEDER-029841, FCT for the PhD grants of R Monteiro (grant number 2020.04988.BD) and AP Magalhaes (grant number SFRH/BD/132165/2017) and for Scientific Employment Stimulus 2017 (CEECIND/01507/2017) provided to AM Sousa. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed, info:eu-repo/semantics/publishedVersion

In a society increasingly dependent on science and technology, the need to equip our students with the most varied digital and communication skills is crucial. Active and collaborative learning among peers is essential for the acquisition of transversal skills. Communication is one of the main tools that the Engineer uses to reach his target audience. Science Communication in Bioengineering and Biotechnology (CCBioTec) is a project on Innovation and Development of Teaching and Learning supported by Center IDEA-UMinho, a structure that emerges to promote and value Innovation and Development of Teaching and Learning at the University of Minho. CCBioTec is transversal to a set of Learning Units (LU) under the responsibility of the Department of Biological Engineering (DEB), including one LU of each year of the Integrated Masters in Biological Engineering and in Biomedical Engineering. The main goals of CCBioTEc are: to foster the awareness of the DEB educational community on the importance of science communication, as well as to develop science communication skills, through the production of short videos (pitches) displaying the explanation, in a simple and dynamic way, of complex concepts of Bioengineering and Biotechnology related with the curricula of each LU. CCBioTec started in the second semester of 2020/21, and it will go on in the 1st semester of 2021/22. The project was designed to be implemented according to the following steps: 1 - Technical and pedagogical training of teachers; 2 - Technical training of students involved in the project - Week CCBioTEC-2021; 3 - Development of materials for Science Communication in Bioengineering and Biotechnology; 4 - CCBioTec-2021 competition. In CCBioTec, teachers presenting himself as a mediator/facilitator of learning, boosting students development of transversal skills, collaborative work, decision making and the expression of ideas, together with the acquisition of knowledge foreseen in the curricular contents of the LU., (undefined), info:eu-repo/semantics/publishedVersion

To boost students engagement on learning outcomes, promote active peer learning, and adopt more dynamic teaching practices, a module of a laboratory course unit (TPL) in engineering was reformulated exploring blended learning. This reformulation was even more challenging than initially anticipated as it was implemented during the Covid-19 pandemic. As TPL learning practises are based on the operation of laboratory modules mimicking heat and mass transfer phenomena, asynchronous and on-line synchronous learning classes and face-to-face laboratory classes were outlined. To promote the asynchronous learning, a full script of TPL and pitch and longer videos presenting, respectively, each work and its practical operation process were formerly prepared and available online. Students were required to work in group to define the variables and conditions to be evaluated in each laboratory module, organize and plan the experimental activities, create data recording documents, and later present and argue their options in virtual synchronous classes. In the face-to-face classes, different activities were performed in a rotating system, scheduled and tuned in the online classes. It was also aimed in-situ promoting peer discussion of the data and reports elaboration, goals not attained due to the pandemic restrictions, as only two students of each group were present in each hands-on class and in sequential times. TPL reformulation was a tough and time-consuming task since 73 students were enrolled, divided into 3 shifts, each one with 5 groups of five students. Students individual learning evolution was inferred through online quizzes that were periodically made available. A final inquiry, launched to obtain students` opinion about this transformation endeavour highlighted the script, videos, and the prompt teachers feedback on the reports as the most fruitful and important aspects for students engagement and guide their learning pathway. The rationale behind this paper was to disclose this transformation experience and share information and strategies that can be used in the teaching/learning of laboratory classes. © 2021 University of Minho. All rights reserved., (undefined), info:eu-repo/semantics/publishedVersion

[Excerpt] Infected Diabetic Foot Ulcers (DFU’s) Infected diabetic foot ulcers (DFUs) are a frequent and costly complication of diabetes, with limb amputation being highly prevalent worldwide. Persistent pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa are the main pathogens of infected DFUs, often gaining antimicrobial-resistance to treatment., Authors acknowledge FCT for supporting the projects with references PTDC/CTM-TEX/28074/2017(POCI-01-0145-FEDER-028074) and UID/CTM/00264/2021. Joana Domingues is also grateful for the FCT PhD grant 2020.07387.BD.

Nesta edição da 4ª Feira da Biotecnologia e Bioengenharia, que tem por tema Engenharia em Mudança, pretende-se fomentar a simbiose entre a academia e o mundo empresarial e industrial, reunindo um leque de oradores de associações empresariais, indústrias e empresas chave na área da biotecnologia e bioengenharia. O objetivo é criar uma interface de divulgação e apresentação das atividades de cada empresa/indústria/organização e de promoção do diálogo e discussão com os alunos do Departamento de Engenharia Biológica e do Centro de Engenharia Biológica., info:eu-repo/semantics/publishedVersion