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The extraintestinal pathogenic Escherichia coli group is characterized by the presence of uropathogenic E. coli (UPEC), sepsis-associated E. coli (SEPEC), and neonatal meningitis E. coli (NMEC). All of these members exhibit many virulence factors, such as lipopolysaccharides, toxins, iron acquisition factors, invasins, fimbriae, and capsules.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) emerge for their capability to better adapt to the human host aimed and enhance human-to-human transmission. Mutations in spike largely contributed to adaptation. Viral persistence is a prerequisite for intra-host virus evolution, and this likely occurred in immunocompromised patients who allow intra-host long-term viral replication. The underlying mechanism leading to the emergence of variants during viral persistence in the immunocompromised host is still unknown. Here, we show the existence of an ensemble of minor mutants in the early biological samples obtained from an immunocompromised patient and their dynamic interplay with the master mutant during a persistent and productive long-term infection. In particular, after 222 days of active viral replication, the original master mutant, named MB610, was replaced by a minor quasispecies (MB61222) expressing two critical mutations in spike, namely Q493K and N501T. Isolation of the two viruses allowed us to show that MB61222 entry into target cells occurred mainly by the fusion at the plasma membrane (PM), whereas endocytosis characterized the entry mechanism used by MB610. Interestingly, coinfection of two human cell lines of different origin with the SARS-CoV-2 isolates highlighted the early and dramatic predominance of MB61222 over MB610 replication. This finding may be explained by a faster replicative activity of MB61222 as compared to MB610 as well as by the capability of MB61222 to induce peculiar viral RNA-sensing mechanisms leading to an increased production of interferons (IFNs) and, in particular, of IFN-induced transmembrane protein 1 (IFITM1) and IFITM2. Indeed, it has been recently shown that IFITM2 is able to restrict SARS-CoV-2 entry occurring by endocytosis. In this regard, MB61222 may escape the antiviral activity of IFITMs by using the PM fusion pathway for entry into the target cell, whereas MB610 cannot escape this host antiviral response during MB61222 coinfection, since it has endocytosis as the main pathway of entry. Altogether, our data support the evidence of quasispecies fighting for host dominance by taking benefit from the cell machinery to restrict the productive infection of competitors in the viral ensemble. This finding may explain, at least in part, the extraordinary rapid worldwide turnover of VOCs that use the PM fusion pathway to enter into target cells over the original pandemic strain.

espanolA pesar de la potencialidad intercultural de la metodologia, la investigacion y la experimentacion en intercomprension se concentran, normalmente, en el desarrollo de la sola competencia linguistica. Este estudio quiere presentar los resultados de una integracion sistematica de objetivos interculturales dentro de un curso experimental de IC escrita de lenguas neolatinas para aprendientes hispanofonos. Con base en el metodo EuRom, se han desarrollado integraciones de materiales didacticos online y de herramientas de observacion del proceso de aprendizaje (cuestionarios) que han permitido evidenciar la pertinencia de una reflexion intercultural basad en el analisis comparativo del discurso. Los resultados de las integraciones propuestas proceden de las evaluaciones y reflexiones de los aprendientes, elaboradas a traves de cuestionarios, que nos permiten una lectura de la ‘percepcion’ del sujeto involucrado en el proceso de aprendizaje no solo desde un punto de vista de factibilidad metodologica y de coherencia pedagogica, sino de apreciacion de la propuesta en terminos cognitivos, afectivos y de evaluacion de procesos y resultados. EnglishDespite the intercultural potential of the methodology, research and experimentation in intercomprehension are usually concentrated in the development of linguistic competence alone. This study aims to present the results of a systematic integration of intercultural objectives within an experimental written IC course in Neo-Latin languages for Spanish-speaking learners. Based on the EuRom method, integrations of on-line didactic materials and observation tools for the learning process (questionnaires) have been developed, which allowed us to demonstrate the relevance of an intercultural reflection based on the comparative analysis of discourse. The results of the integrations come from the evaluations and reflections of the learners, elaborated through questionnaires aiming to read the 'perception' of the subject involved in the learning process not only from a methodological feasibility point of view and of pedagogical coherence, but of appreciation of the proposal in cognitive, affective terms and of evaluation of processes and results.

This paper describes a teacher-training experience delivered in the year 2015-16 by the Dipartimento Formazione e Istruzione Italiana of the Province of Bolzano and addressed to teachers of every school’s level is presented. The purpose of the described training was to share intercomprehension’s theory and practical suggestions in order to increase the intercultural sensitivity and metalinguistic awareness of the participants. The proposal was also meant to reflect about how far an interlinguistic dimension is naturally suited to promote consciousness in comprehension techniques, a necessary competence for teachers working in international contexts, and intercultural ‘contamination’. The paper synthesises the theoretical background of the proposal, based on the strict interdependence between the international character of learners, teachers and institutions and the development of intercultural openness through metacognitive reflections and receptive language skills. At the end, the teacher training proposal is briefly described, together with the participants feedback of the proposal.