Search results for "resistance mechanisms"
showing 4 items of 4 documents
Processing of metals and metalloids by actinobacteria: Cell resistance mechanisms and synthesis of metal(loid)-based nanostructures
2020
Metal(loid)s have a dual biological role as micronutrients and stress agents. A few geochemical and natural processes can cause their release in the environment, although most metal-contaminated sites derive from anthropogenic activities. Actinobacteria include high GC bacteria that inhabit a wide range of terrestrial and aquatic ecological niches, where they play essential roles in recycling or transforming organic and inorganic substances. The metal(loid) tolerance and/or resistance of several members of this phylum rely on mechanisms such as biosorption and extracellular sequestration by siderophores and extracellular polymeric substances (EPS), bioaccumulation, biotransformation, and me…
Long-term genomic coevolution of host-parasite interaction in the natural environment
2017
Antagonistic coevolution of parasite infectivity and host resistance may alter the biological functionality of species, yet these dynamics in nature are still poorly understood. Here we show the molecular details of a long-term phage–bacterium arms race in the environment. Bacteria (Flavobacterium columnare) are generally resistant to phages from the past and susceptible to phages isolated in years after bacterial isolation. Bacterial resistance selects for increased phage infectivity and host range, which is also associated with expansion of phage genome size. We identified two CRISPR loci in the bacterial host: a type II-C locus and a type VI-B locus. While maintaining a core set of conse…
Nueva era en el combate contra el cáncer: Evolución y cáncer: progreso y tratamiento de tumores
2013
L’oncohematologia ha assistit en les últimes dècades a importants avenços en el tractament i supervivència. La toxicitat derivada de la quimioteràpia clàssica i la necessitat de millorar l’eficàcia i tolerància als tractaments han fet que es desencadene un allau d’activitat investigadora que constantment proporciona fruits. Gran part d’aquest esforç s’ha enfocat al desenvolupament de «teràpies diana» dirigides contra determinades alteracions funcionals, clau per a la supervivència de la cèl·lula tumoral. Així es pretén aconseguir major eficàcia en el tractament i que el pacient pague un menor cost en toxicitat. Avenços en altres disciplines de l’oncologia com l’epidemiologia, la cirurgia i …
Molecular epidemiology and drug-resistance mechanisms in carbapenem-resistant Klebsiella pneumoniae isolated in patients from a tertiary hospital in …
2020
Abstract Objectives The aim of this study has been to characterize carbapenem-resistant Klebsiella pneumoniae isolates and to determine the resistance mechanisms involved, the clonal relationship between strains and clinical and demographical data of the infected patients. Methods Clinical and demographical data from patients were collected and statistically analysed. Antimicrobial susceptibility testing was performed and resistance genes were detected both phenotypically and genotypically. Conjugation assays were performed to show horizontal transferability of resistance genes. Clonal relationship was also studied. Next-generation sequencing (NGS) was performed to obtain information regard…