Xavier Úcar Martínez

A microbial signature for Crohn's disease

Objective A decade of microbiome studies has linked IBD to an alteration in the gut microbial community of genetically predisposed subjects. However, existing profiles of gut microbiome dysbiosis in adult IBD patients are inconsistent among published studies, and did not allow the identification of microbial signatures for CD and UC. Here, we aimed to compare the faecal microbiome of CD with patients having UC and with non-IBD subjects in a longitudinal study. Design We analysed a cohort of 2045 non-IBD and IBD faecal samples from four countries (Spain, Belgium, the UK and Germany), applied a 16S rRNA sequencing approach and analysed a total dataset of 115 million sequences. Results In the Spanish cohort, dysbiosis was found significantly greater in patients with CD than with UC, as shown by a more reduced diversity, a less stable microbial community and eight microbial groups were proposed as a specific microbial signature for CD. Tested against the whole cohort, the signature achieved an overall sensitivity of 80% and a specificity of 94%, 94%, 89% and 91% for the detection of CD versus healthy controls, patients with anorexia, IBS and UC, respectively. Conclusions Although UC and CD share many epidemiologic, immunologic, therapeutic and clinical features, our results showed that they are two distinct subtypes of IBD at the microbiome level. For the first time, we are proposing microbiomarkers to discriminate between CD and non-CD independently of geographical regions.

Processing faecal samples: a step forward for standards in microbial community analysis

BackgroundThe microbial community analysis of stools requires optimised and standardised protocols for their collection, homogenisation, microbial disruption and nucleic acid extraction. Here we examined whether different layers of the stool are equally representative of the microbiome. We also studied the effect of stool water content, which typically increases in diarrhoeic samples, and of a microbial disruption method on DNA integrity and, therefore, on providing an unbiased microbial composition analysis.ResultsWe collected faecal samples from healthy subjects and performed microbial composition analysis by pyrosequencing the V4 region of the 16S rRNA gene. To examine the effect of stool structure, we compared the inner and outer layers of the samples (N = 8). Both layers presented minor differences in microbial composition and abundance at the species level. These differences did not significantly bias the microbial community specific to an individual. To evaluate the effect of stool water content and bead-beating, we used various volumes of a water-based salt solution and beads of distinct weights before nucleic acid extraction (N = 4). The different proportions of water did not affect the UniFrac-based clustering of samples from the same subject However, the use or omission of a bead-beating step produced different proportions of Gram-positive and Gram-negative bacteria and significant changes in the UniFrac-based clustering of the samples.ConclusionThe degree of hydration and homogenisation of faecal samples do not significantly alter their microbial community composition. However, the use of bead-beating is critical for the proper detection of Gram-positive bacteria such as Blautia and Bifidobacterium.

Effectiveness of the WC/rBS oral cholera vaccine in the prevention of traveler's diarrhea: a prospective cohort study.

Objective: Traveler’s diarrhea (TD) is the most frequent disease among people from industrialized countries who travel to less developed ones, especially sub-Saharan Africa, Southern Asia and South America. The most common bacteria causing TD is enterotoxigenic Escherichia coli (ETEC). The WC/rBS cholera vaccine (Dukoral®) has been shown to induce cross-protection against ETEC by means of the B subunit of the cholera toxin. The aim of the study was to evaluate the effectiveness of the WC/rBS cholera vaccine in preventing TD. Methods: Between May 1 and September 30 (2007), people seeking pre-travel advice in ten Spanish international vaccination centers were included in a prospective cohort study of travelers to cholera risk countries. The incidence rates of TD were adjusted for variables whose frequencies were statistically different (entry point 0.10) between the vaccinated and non-vaccinated cohorts. Findings: The vaccinated cohort (n = 544 travelers) included people vaccinated with the WC/rBS cholera vaccine, and the non-vaccinated cohort (n = 530 travelers) by people not vaccinated. The cumulative incidence rate of TD was 1.69 in vaccinated and 2.14 in non-vaccinated subjects. The adjusted relative risk of TD in vaccinated travelers was 0.72 (95% CI: 0.58–0.88) and the adjusted vaccination effectiveness was 28% (95% CI: 12–42). Conclusions: The WC/rBS cholera vaccine prevents TD in 2 out of 7 travelers (preventive fraction: 28%). The number needed to vaccinate (NNV) to prevent 1 case of TD is 10.

Vaccination of patients with inflammatory bowel disease: Practical recommendations

Patients with inflammatory bowel disease (IBD) have a greater risk of infection associated with the endogenous immunosuppression brought about by their underlying disease as well as the exogenous immunosuppression resulting from their therapies. In the last few years guidelines and consensus papers have been issued on the indication of vaccines for these patients as primary prevention of infection. However, vaccine coverage is low, likely because the risk for infection and both safety and efficacy concerns regarding vaccines are scarcely perceived in such cases. The available scientific evidence shows that immunization is safe for most preparations, and bears no association with an increased risk for disease activity. This paper reviews the available scientific literature, and provides recommendations on the vaccination of adults with IBD.

OriginalCobertura de vacunación antineumocócica en niños con condiciones de riesgo en CataluñaPneumococcal vaccination coverage in at-risk children in Catalonia☆

INTRODUCTION The public health system in Catalonia only funds pneumococcal vaccination in paediatrics for children at-risk. The aim of this study was to determine pneumococcal vaccination coverage and its association with age, sociodemographic factors and other variables. MATERIAL AND METHOD Descriptive cross-sectional study of children aged between 2 months and 15 years old assigned to primary care centres in Catalonia and with diseases that are included for pneumococcal vaccine in the official vaccination program. The information on vaccination status and study variables were obtained from data registered in the electronic medical records in the primary care centres. An analysis was made of the association between pneumococcal vaccination and demographic and medical variables using bivariate analysis and a multiple logistic regression model. The adjusted odds ratio (aOR), with a confidence interval of 95%, was used to measure the relationships. RESULTS Pneumococcal vaccination coverage was 47.7%. Variables which predicted pneumococcal vaccination were: age (aOR: 9.2 [7.9-10.7] in children 2 months-2 years old; aOR 8.1 [7.0-9.3] in children 3-5 years; aOR: 4.6 [4.0-5.2] in children 6-10 years), Spanish nationality (aOR: 3.9 [3.5-4.3]), correct immunisation according to systematic immunisation schedule (aOR: 2.5 [2.1-3.0]), and number of risk conditions (aOR: 3.2 [2.5-4.1] in children with 2 or more conditions). CONCLUSIONS Pneumococcal vaccination coverage in children with risk conditions is low in Catalonia. Strategies need to be implemented to increase coverage.

Cobertura de vacunación antineumocócica en niños con condiciones de riesgo en Cataluña

INTRODUCTION The public health system in Catalonia only funds pneumococcal vaccination in paediatrics for children at-risk. The aim of this study was to determine pneumococcal vaccination coverage and its association with age, sociodemographic factors and other variables. MATERIAL AND METHOD Descriptive cross-sectional study of children aged between 2 months and 15 years old assigned to primary care centres in Catalonia and with diseases that are included for pneumococcal vaccine in the official vaccination program. The information on vaccination status and study variables were obtained from data registered in the electronic medical records in the primary care centres. An analysis was made of the association between pneumococcal vaccination and demographic and medical variables using bivariate analysis and a multiple logistic regression model. The adjusted odds ratio (aOR), with a confidence interval of 95%, was used to measure the relationships. RESULTS Pneumococcal vaccination coverage was 47.7%. Variables which predicted pneumococcal vaccination were: age (aOR: 9.2 [7.9-10.7] in children 2 months-2 years old; aOR 8.1 [7.0-9.3] in children 3-5 years; aOR: 4.6 [4.0-5.2] in children 6-10 years), Spanish nationality (aOR: 3.9 [3.5-4.3]), correct immunisation according to systematic immunisation schedule (aOR: 2.5 [2.1-3.0]), and number of risk conditions (aOR: 3.2 [2.5-4.1] in children with 2 or more conditions). CONCLUSIONS Pneumococcal vaccination coverage in children with risk conditions is low in Catalonia. Strategies need to be implemented to increase coverage.

Emergence of Bordetella holmesii as a Causative Agent of Whooping Cough, Barcelona, Spain.

We describe the detection of Bordetella holmesii as a cause of whooping cough in Spain. Prevalence was 3.9% in 2015, doubling to 8.8% in 2016. This emergence raises concern regarding the contribution of B. holmesii to the reemergence of whooping cough and the effectiveness of the pertussis vaccine.

Fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 reduces bacterial translocation in rats treated with carbon tetrachloride

Probiotics can prevent pathological bacterial translocation by modulating intestinal microbiota and improving the gut barrier. The aim was to evaluate the effect of a fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 on bacterial translocation in rats with carbon tetrachloride (CCl4)-induced cirrhosis. Sprague-Dawley rats treated with CCl4 were randomized into a probiotic group that received fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 in drinking water or a water group that received water only. Laparotomy was performed one week after ascites development. We evaluated bacterial translocation, intestinal microbiota, the intestinal barrier and cytokines in mesenteric lymph nodes and serum. Bacterial translocation decreased and gut dysbiosis improved in the probiotic group compared to the water group. The ileal β-defensin-1 concentration was higher and ileal malondialdehyde levels were lower in the probiotic group than in water group. There were no differences between groups in serum cytokines but TNF-α levels in mesenteric lymph nodes were lower in the probiotic group than in the water group. Fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 decreases bacterial translocation, gut dysbiosis and ileal oxidative damage and increases ileal β-defensin-1 expression in rats treated with CCl4, suggesting an improvement in the intestinal barrier integrity.

La construcción de un modelo pedagógico del empoderamiento juvenil: espacios, momentos y procesos

The present paper is the result of a research project (EDU2013-42979-R) which investigated youth empowerment from different perspectives. The initial question was where, when and how youth empowerment takes place. The aim was to build an educational model that could serve as guidance for the organization and study of these spaces, moments and processes. The starting point was a previous extensive documentary analysis that formulated an initial conceptualization of youth empowerment. It was based on the review of 297 biblio¬graphical references from the year 2000 onwards that addressed youth empowerment from a socio-educational perspective. The methodology consisted in the reflective analysis of the abovementioned documentary sources and the subsequent systematization of the data ob¬tained, in order to build a reasoned and well-argued theoretical proposal. This paper provides its own definition of youth empowerment by focusing on previous studies carried out by the research team and on M. Nussbaum’s capabilities approach. A general pattern was constructed in the form of an educational model intended to offer a benchmark to describe, explain and interpret youth empowerment, as well as to plan and guide interventions intended to optimize it. We conclude with some final reflections on some possible—but undesirable—ways to understand and exploit these empowerment processes.espanolEl presente articulo es fruto de un proyecto de investigacion (EDU2013-42979-R) en el que se profundiza desde diferentes perspectivas en el empoderamiento juvenil. En la aportacion que aqui presentamos partimos de la pregunta inicial de donde, cuando y como tiene lugar el empoderamiento juvenil. Se pretende construir un modelo educativo que pue¬da servir de orientacion para ordenar y estudiar estos espacios, momentos y procesos. Se parte de un extenso trabajo previo de analisis documental en el que se formulaba una pri¬mera conceptualizacion del empoderamiento juvenil a partir del analisis de 297 referencias bibliograficas posteriores al ano 2000 que abordaban desde una perspectiva socioeducativa el empoderamiento juvenil. En la presente aportacion partimos de este trabajo realizado y en esta ocasion la metodologia utilizada ha consistido en el analisis reflexivo de dichas fuentes documentales y la posterior sistematizacion de los datos obtenidos con el proposito de cons¬truir una propuesta teorica razonada y convenientemente argumentada. El articulo fundamenta una definicion propia de empoderamiento juvenil centrada en trabajos anteriores del equipo de investigacion y en el enfoque de capacidades de M. Nuss¬baum. Se articula un patron general, en forma de modelo pedagogico, con el proposito de presentar un referente con el que poder describir, explicar e interpretar el empoderamiento de los jovenes, asi como proyectar y orientar intervenciones para optimizarlo. Se concluye con unas reflexiones finales sobre ciertas formas posibles pero indeseables de entender o instrumentalizar los procesos de empoderamiento EnglishThe present paper is the result of a research project (EDU2013-42979-R) which investigated youth empowerment from different perspectives. The initial question was where, when and how youth empowerment takes place. The aim was to build an educational model that could serve as guidance for the organization and study of these spaces, moments and processes. The starting point was a previous extensive documentary analysis that formulated an initial conceptualization of youth empowerment. It was based on the review of 297 bibliographical references from the year 2000 onwards that addressed youth empowerment from a socio-educational perspective. The methodology consisted in the reflective analysis of the abovementioned documentary sources and the subsequent systematization of the data obtained, in order to build a reasoned and well-argued theoretical proposal. This paper provides its own definition of youth empowerment by focusing on previous studies carried out by the research team and on M. Nussbaum’s capabilities approach. A general pattern was constructed in the form of an pedagogical model intended to offer a benchmark to describe, explain and interpret youth empowerment, as well as to plan and guide interventions intended to optimize it. We conclude with some final reflections on some possible—but undesirable—ways to understand and exploit these empowerment processes portugues: O presente artigo e fruto de um projeto de investigacao (EDU2013-42979-R) no qual se aprofunda a capacitacao juvenil de varias perspetivas. No contributo que aqui apresentamos, partimos da pergunta inicial de onde, quando e como acontece a capacitacao juvenil. Pretende-se criar um modelo educativo que possa servir de orientacao para ordenar e estudar estes espacos, momentos e processos. Parte-se de um extenso trabalho previo de analise documental no qual se formulou uma primeira conceptualizacao da capacitacao juvenil a partir da analise de 297 referencias bibliograficas posteriores ao ano 2000 que abordavam a capacitacao juvenil de uma perspetiva socioeducativa. No presente contributo, partimos deste trabalho realizado e, nesta ocasiao, a metodologia utilizada consistiu na ana- lise reflexiva das ditas fontes documentais e na posterior sistematizacao dos dados obtidos com o proposito de elaborar uma proposta teorica bem fundamentada e convenientemente argumentada. O artigo fundamenta uma definicao propria de capacitacao juvenil centrada em trabalhos anteriores da equipa de investigacao e na abordagem de competencias de M. Nussbaum. Articula-se um padrao geral, em forma de modelo pedagogico, com o proposito de apresentar um referente com o poder de descrever, explicar e interpretar a capacitacao dos jovens, assim como projetar e orientar intervencoes para o otimizar. Conclui-se com umas reflexoes finais sobre certas formas possiveis, mas indesejaveis, de entender ou instrumentalizar os processos de capacitacao.

Evaluación participativa y empoderamiento

Presentacion del numero monografico sobre evaluacion participativa y empoderamiento que coordina el Catedratico Xavier Ucar.