The Animal Food Supplement Sepiolite Promotes a Direct Horizontal Transfer of Antibiotic Resistance Plasmids between Bacterial Species

Animal fodder is routinely complemented with antibiotics together with other food supplements to improve growth. For instance, sepiolite is currently used as a dietary coadjuvant in animal feed, as it increases animal growth parameters and improves meat and derived final product quality. This type of food additive has so far been considered innocuous for the development and spread of antibiotic resistance. In this study, we demonstrate that sepiolite promotes the direct horizontal transfer of antibiotic resistance plasmids between bacterial species. The conditions needed for plasmid transfer (sepiolite and friction forces) occur in the digestive tracts of farm animals, which routinely receive sepiolite as a food additive. Furthermore, this effect may be aggravated by the use of antibiotics supplied as growth promoters.     

Subversion of innate and adaptive immune activation induced by structurally modified lipopolysaccharide from Salmonella typhimurium

Salmonella are successful pathogens that infect millions of people every year. During infection, Salmonella typhimurium changes the structure of its lipopolysaccharide (LPS) in response to the host environment, rendering bacteria resistant to cationic peptide lysis in vitro. However, the role of these structural changes in LPS as in vivo virulence factors and their effects on immune responses and the generation of immunity are largely unknown. We report that modified LPS are less efficient than wild‐type LPS at inducing pro‐inflammatory responses. The impact of this LPS‐mediated subversion of innate immune responses was demonstrated by increased mortality in mice infected with a non‐lethal dose of an attenuated S. typhimurium strain mixed with the modified LPS moieties. Up‐regulation of co‐stimulatory molecules on antigen‐presenting cells and CD4⁺ T‐cell activation were affected by these modified LPS. Strains of S. typhimurium carrying structurally modified LPS are markedly less efficient at inducing specific antibody responses. Immunization with modified LPS moiety preparations combined with experimental antigens, induced an impaired Toll‐like receptor 4‐mediated adjuvant effect. Strains of S. typhimurium carrying structurally modified LPS are markedly less efficient at inducing immunity against challenge with virulent S. typhimurium. Hence, changes in S. typhimurium LPS structure impact not only on innate immune responses but also on both humoral and cellular adaptive immune responses.     

Mediterranean Diet,Screen-Time-Based Sedentary Behavior and Their Interaction Effect on Adiposity in European Adolescents: The HELENA Study

Childhood obesity is a worldwide epidemic. Mediterranean diet (MD) is inversely associated with childhood obesity, but the interaction with other environmental factors, such screen time, might influence the health benefits of a high MD adherence in adolescents. The aim of the present study was to assess whether an association between MD and screen time exists in European adolescents. Moreover, we also explored whether sedentary time has a modulatory effect on the association between MD and adiposity. Adherence to the MD (24 h recalls), screen time (questionnaire), pubertal development, body mass index (BMI), fat mass index (FMI) and waist circumference (WC) were evaluated in 2053 adolescents (54.7% females), aged 12.5–17.5 years. In females, MD adherence was associated with lower BMI and FMI only when they were exposed to less than 338 min/day of screen time (81.8% of females); MD adherence was also associated with lower WC only when females were exposed to less than 143 min/day of screen time (31.5% of females). No significant MD-screen time interaction was observed in males. In conclusion, screen-time-based sedentary behaviours had a modulatory effect in the association between MD adherence and adiposity in European female adolescents.     

Durability and clinical experience using a bovine pericardial prosthetic aortic valve

ObjectivesTo report the implant experience and long-term outcomes from a large tertiary care referral center on surgical aortic valve replacement (SAVR) with a contemporary stented pericardial bioprosthesis with anticalcification treatment.MethodsPatients underwent SAVR using the Trifecta valve at a single institution. Endpoints included procedural outcomes, adverse events, prosthesis–patient mismatch (PPM), long-term survival, and valve durability. Follow-up included 30-day, 6-month, and annual assessments. Treatment for structural valve deterioration (SVD) included surgical explant and valve-in-valve (V-in-V) transcatheter aortic valve implantation (TAVI).ResultsSAVR was performed in 1241 patients (median age, 73.5 ± 6.4 years; 54% male; median logistic EuroSCORE, 7.8) with concomitant procedures in 713 cases (57.5%). Intraprocedural mortality was 1.4%, and 30-day mortality was 6.0%. At hospital discharge, 68 patients (5.5%) had moderate PPM, and no patients had severe PPM. Adverse events included cardiac arrhythmias (44.7%, mostly atrial fibrillation), respiratory failure (22.9%), acute renal failure requiring temporary renal replacement therapy (12.9%), and low cardiac output syndrome (3.3%). Follow-up data were available over a total of 5469 patient-years (median duration of follow-up, 4.7 years). Freedom at 8 years from all-cause mortality, valve-related mortality, reoperation for SVD (redo SAVR or V-in-V TAVI), and endocarditis were 78.4%, 98.0%, 93.3%, and 96.5%, respectively. Of the 30 patients with SVD, 17 were treated by V-in-V TAVI and 13 underwent surgical explant.ConclusionsOutcomes from this large single-center cohort at increased surgical risk demonstrate excellent long-term durability of the Trifecta valve for SAVR and feasibility of treating SVD by V-in-V TAVI.     

Head actinomycetoma with a double aetiology, caused by Nocardia brasiliensis and N. asteroides

We describe a 64-year-old man with an actinomycetoma of the frontal region of the head caused simultaneously by two aetiological agents, Nocardia brasiliensis and N. asteroides. This case is presented due to the unusual body site affected and, above all, because two aetiological agents were isolated.