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Acceso AbiertoArtículo
Antimicrobial susceptibility trends and evolution of isolates with extended spectrum β-lactamases among Gram-negative organisms recovered during the SMART study in Spain (2011-2015)
(Sociedad Española de Quimioterapia, 2018) Cantón, Rafael; Loza, Elena; Aznar Martín, Javier; Barrón Adúriz, Rubén; Calvo, Jorge; Castillo, F. Javier; Pascual Hernández, Álvaro; Universidad de Sevilla. Departamento de Microbiología
Introduction. The SMART (Study for Monitoring Antimicrobial Resistance Trends) surveillance study monitors antimicrobial susceptibility and extended spectrum β-lactamases (ESBLs) in Gram-negative bacilli recovered from intra-abdominal infections (IAI). Material and methods. Antimicrobial susceptibility of 5,343 isolates from IAI recovered in 11 centres during the 2011-2015 SMART-Spain program was analysed by standard microdilution (EUCAST criteria) and compared with that from 2002-2010. ESBLs were phenotypically detected. Results. Escherichia coli, the most common isolate, significantly decreased in community acquired IAI (60.9% 2002-2010 vs. 56.1% 2011-2015, P=0.0003). It was followed in prevalence by Klebsiella pneumoniae that increased both in the community (8.9% vs. 10.8%, P=0.016) and nosocomial (9.2% vs. 10.8%, P=0.029) IAI and P. aeruginosa, which significantly increased in community acquired IAI (5.6% vs. 8.0%, P=0.0003). ESBLs were more prevalent in K. pneumoniae (16.3%) than in E. coli (9.5%) of nosocomial origin and were more frequently isolated from elderly patients (>60 years). Considering all Enterobacteriaceae, ertapenem (92.3-100%) and amikacin (95.5%-100%) were the most active antimicrobials. Ertapenem activity, unlike amoxicillinclavulanate or piperacillin-tazobactam, remained virtually unchanged in ESBL (100%) and non-ESBL (98.8%) E. coli producers. Its activity decreased in ESBL-K. pneumoniae (74.7%) but was higher than that of amoxicillin-clavulanate (14.0%) and piperacillin-tazobactam (24.0%). Interestingly, ertapenem susceptibility was maintained in >60% of ESBL isolates that were resistant to amoxicillin-clavulanate, piperacillin-tazobactam or fluoroquinolones. Conclusions. SMART-Spain results support current guidelines which include ertapenem as empiric treatment in mild-moderate community-acquired IAI, particularly with ESBL producers. These recommendations will need to be updated with the recently introduction of new antimicrobials.
Miniatura
Acceso AbiertoArtículo
Reactivity of aragonite with dicalcium phosphate facilitates removal of dental calculus
(Springer, 2025) Elhadad, Amir A.; Basiri, Tayebeh; Al-Hashedi, Ashwaq; Smith, Sophia; Moussa, Hanan; Veettil, Sadiya; Pérez-Soriano, Eva María; Tamimi, Faleh; Universidad de Sevilla. Departamento de Ingeniería y Ciencia de los Materiales y del Transporte
Dental calculus, a main contributor of periodontal diseases, is mostly composed of inorganic calcium phosphate species such as dicalcium phosphate, whitlockite, octa calcium phosphate, and hydroxyapatite. Under physiological pH 7.4, dicalcium phosphates can gradually interact with calcium carbonate to form hydroxyapatite. Therefore, we hypothesized that aragonite (Arg) could react with dental calculus, facilitating its removal. To assess the reactivity of Arg with dental calculus, we examined the changes in surface morphology, composition, and topography of Arg and dental calculus upon exposure to each other in an aqueous environment. The impact of Arg on the removal of dental calculus was assessed by brushing polished sections of dental calculus, enamel, and dentin with slurries of Arg and measuring the depth of abrasion using a stylus profilometer. Our results demonstrate that Arg can react with dental calculus in aqueous environment. This reaction increases calculus surface roughness which in turn facilitate dental calculus removal by brushing. Aragonite could be a promising abrasive for toothpaste design for management of dental calculus.
Miniatura
Acceso AbiertoArtículo
Patients' perceptions of the impact of ulcerative colitis on social and professional life: results from the UC-LIFE survey of outpatient clinics in Spain
(Dovepress, 2018-09-18) Calvet, Xavier; Argüelles Arias, Federico; López-Sanromán, Antonio; Cea-Calvo, Luis; Berta, Julia; De Santos, Cristina Romero; Carpio, Daniel; Universidad de Sevilla. Departamento de Medicina
Purpose: Ulcerative colitis (UC) may cause many patients to miss out on important personal and professional opportunities. We therefore conducted a survey (UC-LIFE) to assess patients’ perceptions of the impact of UC on social and professional lives. Patients and methods: Consecutive unselected UC patients aged $18 years were recruited from 38 outpatient clinics in Spain. Patients completed the survey at home, returning it by post. The survey comprised 44 multiple-choice questions, including questions about the impact of UC on social, personal, professional, and academic activities. Results: Of 585 patients invited, 436 (75%) returned the survey (mean age 46 years; 47% women). High proportions of patients considered their disease “sometimes”, “frequently” or “mostly/always” influenced leisure activities (65.1%), recreational or professional activities (57.6%), or relationships with relatives or friends (9.9%). Patients also reported that UC influenced their decision to have children (17.2%), or their ability to take care of children (40.7%); these percentages were higher in women and in younger patients. Overall, 47.0% of patients declared that UC influenced the kind of job they performed, 20.3% had rejected a job due to UC, 14.7% had lost a job due to UC, and 19.4% had had academic problems due to UC. Conclusion: Beyond symptoms alone, UC imposes an enormous additional burden on patients’ social, professional, and family lives. This extra burden clearly needs to be addressed so that the ultimate goal of IBD treatment – normalization of patient quality of life – can be attained by as many patients as possible.
Miniatura
Acceso AbiertoArtículo
Evolution of the Quorum network and the mobilome (plasmids and bacteriophages) in clinical strains of Acinetobacter baumannii during a decade
(Nature Research, 2018-02-06) López, M.; Rueda, A.; Florido, J.P.; Blasco, L.; Fernández-García, L.; Trastoy, R.; Pascual Hernández, Álvaro; Tomas, M.; Universidad de Sevilla. Departamento de Microbiología; Instituto de Salud Carlos III; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Gobierno de España; Xunta de Galicia
In this study, we compared eighteen clinical strains of A. baumannii belonging to the ST-2 clone and isolated from patients in the same intensive care unit (ICU) in 2000 (9 strains referred to collectively as Ab_GEIH-2000) and 2010 (9 strains referred to collectively as Ab_GEIH-2010), during the GEIH-REIPI project (Umbrella BioProject PRJNA422585). We observed two main molecular differences between the Ab_GEIH-2010 and the Ab_GEIH-2000 collections, acquired over the course of the decade long sampling interval and involving the mobilome: i) a plasmid harbouring genes for blaOXA 24/40 ß-lactamase and abKA/abkB proteins of a toxin-antitoxin system; and ii) two temperate bacteriophages, Ab105-1ϕ (63 proteins) and Ab105-2ϕ (93 proteins), containing important viral defence proteins. Moreover, all Ab_GEIH-2010 strains contained a Quorum functional network of Quorum Sensing (QS) and Quorum Quenching (QQ) mechanisms, including a new QQ enzyme, AidA, which acts as a bacterial defence mechanism against the exogenous 3-oxo-C12-HSL. Interestingly, the infective capacity of the bacteriophages isolated in this study (Ab105-1ϕ and Ab105-2ϕ) was higher in the Ab_GEIH-2010 strains (carrying a functional Quorum network) than in the Ab_GEIH-2000 strains (carrying a deficient Quorum network), in which the bacteriophages showed little or no infectivity. This is the first study about the evolution of the Quorum network and the mobilome in clinical strains of Acinetobacter baumannii during a decade.
Miniatura
Acceso AbiertoArtículo
A Photovoltaic Dynamic Vision Sensor
(Institute of Electrical and Electronics Engineers Inc., 2025) Fernández Peramo, Pablo; Leñero Bardallo, Juan Antonio; Rodríguez Vázquez, Ángel Benito; Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); European Union (UE)
This article reports a dynamic vision sensor (DVS) proof-of-concept chip employing an unconventional photo-transduction front end. Instead of the conventional logarithmic transducer comprising a photodiode and a nonlinear load, the proposed pixel architecture uses a single diode operating in the photovoltaic regime. This operation regime, the same as employed for solar cells, features a voltage-current characteristic that endows the sensor with remarkable sensitivity to transient illumination variations, particularly in low-light conditions. Also, the lack of resistive loads benefits compactness and decreases static power consumption. Experimental results with the sensor in the article demonstrate advantages over previous art regarding noise and latency.
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