Simultaneous determination of food allergens by multiple analysis strips

Motivation: Some substances in food, even in small traces, are responsible of severe allergic reactions becoming harmful to human health of sensitized individuals. Therefore, the food sector is forced to produce innocuous food for consumers by implementing safety management systems and using labeled to alert of the presence of allergens. Consequently, the monitoring of cross-contamination of materials during production lines and proper labeling of ingredients is crucial in quality control in the food industry. Currently, the presence of food allergens is determined by analytical techniques such as ELISA or PCR in real time [1]. However, there is not a technique that can simultaneously analyze a variety of allergens in order to avoid expensive and difficult individual analysis. The aim of this work is the construction of a new analysis system based on a serie of test strips, which allow the simultaneous detection of more than one type of allergen in the same food and in a short time.Methods: The basis of this system is the use of different antibodies bound to an enzyme and immobilized in, that bind to specific areas of each allergen (specific proteins) test strips [2][3]. This antigen-antibody complex mobilizes and be joined to other immobilized antibody, producing a positive colorimetric signal. In the absence of allergen in the sample, the first antibody is mobilized but not joined to second antibody and then there isn’t positive signal indicating the presence of allergens. All the construction has a control system where the primary antibody will bind to a third immobilized antibody, generating a signal indicating that the scanning process has been carried out properly [4].Results: The validation of the system through different assays with positive controls at different concentrations of allergens is carried out. Consecuently, the obtained results verify that the analytical system is working properly and the detection limit is calculated

Epidemiologic and clinical impact of acinetobacter baumannii colonization and infection: A reappraisal

Abstract: Acinetobacter baumannii is one of the most important antibiotic-resistant nosocomial bacteria. We investigated changes in the clinical and molecular epidemiology of A. baumannii over a 10-year period. We compared the data from 2 prospective multicenter cohort studies in Spain, one performed in 2000 (183 patients) and one in 2010 (246 patients), which included consecutive patients infected or colonized by A. baumannii. Molecular typing was performed by repetitive extragenic palindromic polymerase chain reaction (REP-PCR), pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST). The incidence density of A. baumannii colonization or infection increased significantly from 0.14 in 2000 to 0.52 in 2010 in medical services (p<0.001). The number of non-nosocomial health careassociated cases increased from 1.2% to 14.2%, respectively (p<0.001). Previous exposure to carbapenems increased in 2010(16.9% in 2000 vs 27.3% in 2010, p¼0.03). The drugs most frequently used for definitive treatment of patients with infections were carbapenems in 2000 (45%) and colistin in 2010 (50.3%). There was molecular-typing evidence of an increase in the frequency of A. baumannii acquisition in non-intensive care unit wards in 2010 (7.6% in 2000 vs 19.2% in 2010, p¼0.01). By MSLT, the ST2 clonal group predominated and increased in 2010. This epidemic clonal group was more frequently resistant to imipenem and was associated with an increased risk of sepsis, although not with severe sepsis or mortality. Some significant changes were noted in the epidemiology of A. baumannii, which is increasingly affecting patients admitted to conventional wards and is also the cause of non-nosocomial health care-associated infections. Epidemic clones seem to combine antimicrobial resistance and the ability to spread, while maintaining their clinical virulence.ACKNOWLEDGMENTS: The authors thank the Platform for Genotyping of Pathogens and Public Health (Institut Pasteur, Paris, France) for coding MLST alleles and profiles as available at www. pasteur.fr/mlst. The authors are grateful for the support of the Spanish Group for Nosocomial Infections (GEIH) and the Spanish Group for Antimicrobial Mechanisms of Action and Resistance (GEMARA) from the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) for their support in the development of the project

Acinetobacter baumannii in critically ill patients: Molecular epidemiology, clinical features and predictors of mortality

[Introduction] The main aim of this study was to assess changes in the epidemiology and clinical presentation of Acinetobacter baumannii over a 10-year period, as well as risk factors of mortality in infected patients.[Method] Prospective, multicentre, hospital-based cohort studies including critically ill patients with A. baumannii isolated from any clinical sample were included. These were divided into a first period (“2000 study”) (one month), and a second period (“2010 study”) (two months). Molecular typing was performed by REP-PCR, PFGE and MSLT. The primary endpoint was 30-day mortality.[Results] In 2000 and 2010, 103 and 108 patients were included, and the incidence of A. baumannii colonization/infection in the ICU decreased in 2010 (1.23 vs. 4.35 cases/1000 patient-days; p < 0.0001). No differences were found in the colonization rates (44.3 vs. 38.6%) or infected patients (55.7 vs. 61.4%) in both periods. Overall, 30-day mortality was similar in both periods (29.1 vs. 27.8%). The rate of pneumonia increased from 46.2 in 2000 to 64.8% in 2010 (p < 0.001). Performing MSLT, 18 different sequence types (ST) were identified (18 in 2000, 8 in 2010), but ST2 and ST79 were the predominant clones. ST2 isolates in the ICU increased from 53.4% in the year 2000 to 73.8% in 2010 (p = 0.002). In patients with A. baumannii infection, the multivariate analysis identified appropriate antimicrobial therapy and ST79 clonal group as protective factors for mortality.[Conclusions] At 10 years of the first analysis, some variations have been observed in the epidemiology of A. baumannii in the ICU, with no changes in mortality. Epidemic ST79 clone seems to be associated with a better prognosis and adequate treatment is crucial in terms of survival.[Introducción] El principal objetivo fue evaluar los cambios en la epidemiología a lo largo de un periodo de 10 años, así como la presentación clínica y los factores predictores de mortalidad en los pacientes críticos infectados por Acinetobacter baumannii.[Método] Estudio de cohortes prospectivo y multicéntrico en el que se incluyeron pacientes críticos con A. baumannii aislado de cualquier muestra clínica. Se consideró un primer período («estudio de 2000») (un mes) y un segundo («estudio de 2010») (2 meses). La tipificación molecular se realizó mediante REP-PCR, PFGE y MSLT. La variable resultado primaria fue la mortalidad a los 30 días.[Resultados] En 2000 y 2010 se incluyeron 103 y 108 pacientes, respectivamente, y la incidencia de colonización/infección por A. baumannii en la UCI disminuyó en 2010 respecto al 2000 (1,23 vs. 4,35 casos/1.000 pacientes-días; p < 0,0001). No se encontraron diferencias en la tasa de colonización (44,3 vs. 38,6%) o infección (55,7 vs. 61,4%) en ambos periodos. En general, la mortalidad a los 30 días fue similar en ambos periodos (29,1 vs. 27,8%). La tasa de neumonía aumentó desde el 46,2% en 2000 al 64,8% en 2010 (p < 0,001). Mediante MSLT, se identificaron 18 tipos de secuencias diferentes (ST) (18 en 2000, 8 en 2010), pero ST2 y ST79 fueron los clones predominantes. La identificación de ST2 aumentó en la UCI desde el 53,4% en 2000 al 73,8% en 2010 (p = 0,002). En los pacientes infectados, el tratamiento antimicrobiano apropiado y el grupo clonal ST79 fueron factores protectores de mortalidad en el análisis multivariante.[Conclusiones] A los 10 años del primer análisis se han observado algunos cambios en la epidemiología de A. baumannii en la UCI, sin cambios en la mortalidad. El clon ST79 epidémico parece estar asociado con un mejor pronóstico, y el tratamiento adecuado es crucial en términos de supervivencia.Peer reviewe