349 research outputs found
The Human Microbiome and Recurrent Abdominal Pain in Children
This project explores the nature of the human intestinal microbiome in healthy children and children with recurrent abdominal pain. The overall goal is to obtain a robust knowledge base of the intestinal microbiome in children without evidence of pain or gastrointestinal disease and in those with recurrent abdominal pain (functional abdominal pain (FAP) and FAP associated with changes in bowel habits, i.e., irritable bowel syndrome or IBS). Specific aims include: 1. Characterize the composition of the gut microbiome in healthy children by DNA sequencing. 2. Determine the presence of disease-specific organism signatures of variable gut microbiomes in children with recurrent abdominal pain. 3. Perform functional gut metagenomics by evaluation of whole community gene expression profiles and discovery of disease-specific pathway signatures. Multiple strategies have been deployed to navigate and understand the nature of the intestinal microbiome in childhood. These strategies included 454 pyrosequencing-based strategies to sequence 16S rRNA genes and understand the detailed composition of microbes in healthy and disease groups. Microarray-based hybridization with the PhyloChip and quantitative real-time PCR (qPCR) probes were applied as complementary strategies to gain an understanding of the intestinal microbiome from various perspectives. Data collected and analyzed during the HMP UH2 Demo project, from a set of healthy and IBS children (7-12 yo) may enable the identification of core microbiomes in children, in addition to variable components that may distinguish healthy from diseased pediatric states. Twenty-two children with IBS and twenty-two healthy children were enrolled and analyzed in the UH2 phase of this study. The planned enrollment targets for the UH2/3 phases include 50 healthy children, 50 children with FAP and 50 children with IBS (minimum of 3 time points per child). We are currently analyzing the dataset for the presence of disease-specific signatures in the human microbiome, and correlating these microbial signatures with pediatric health or IBS disease status in addition to IBS subtype (e.g., diarrhea-vs constipation-predominant). In the next phase, whole genome shotgun sequencing and metatranscriptomics will be performed with a subset of children in each group. This study explores the nature of core and variable human microbiome in pre-adolescent healthy children and children with IBS. 

Clinical components and associated behavioural aspects of a complex healthcare intervention : Multi-methods study of selective decontamination of the digestive tract in critical care
Copyright © 2013 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.Peer reviewedPostprin
O ensino de didática e a atuação do professor formador na visão de licenciandos de educação artística
Resumo Este artigo decorre de um estudo com 52 estudantes de um curso de licenciatura em educação artística, que teve por objetivo analisar a aprendizagem da docência construída no contexto das disciplinas de didática, considerando o que se ensina, como se ensina e a influência do professor formador a partir do que ele próprio faz para ensinar. A opção por investigar esse curso se justifica porque a sua estrutura curricular, na instituição de ensino superior (IES) pesquisada, ainda se ancora na didática de cunho tecnicista, desafiando os formadores de professores que trabalham com a formação em didática na perspectiva crítica. Para a obtenção dos dados, foi utilizado um questionário, aplicado aos estudantes, conjugado com a realização de grupo de discussão. Teoricamente, a pesquisa se desenvolveu a partir da compreensão de que o ato de ensinar envolve a ação especializada do professor para promover a aprendizagem de seus alunos. Porque a ação é especializada, aquele que a realiza necessita mobilizar saberes específicos, reconhecidos academicamente como base de conhecimento profissional docente. As análises evidenciam que o objeto da didática é nuclear no ensino, mas a abordagem de metodologias sem resvalar para a perspectiva tecnicista ainda é o principal desafio do formador; o estágio é reconhecido como potente espaço/tempo de formação em didática; e a influência do formador no processo de constituição profissional docente é relevada
Guided portfolio writing as a scaffold for reflective learning in in-service contexts: A case study
Language is widely recognized as an inescapable mediating tool for professional learning, and with this text we want to contribute to a better understanding of the particular role that guided writing can play in in-service professional reflective learning. We analysed one pre-school teacher’s written portfolio, the construction of which was guided to scaffold deep thinking about (and the transference of theory into) practice during participation in an in-service program about language education. Our case study shows that the writing process sustained robust learning about professional knowing, doing and learning itself: The teacher elaborated an integrative ethical understanding of the discussed theory, fully experienced newly informed practices and assessed her own learning by using theory to confront her previous knowledge and practices. Throughout the portfolio, the learning stance revealed by her voice varied accordingly. The study illustrates the potential of guided writing to scaffold reflective learning in in-service contexts.Fundação para a Ciência e a Tecnologia (FCT), Portugal. PEst-OE/CED/UI1661/2011] through CIEd (Centro de Estudos em Educação). PEst-OE/CED/UI0317/2014] through CIEC.info:eu-repo/semantics/publishedVersio
Selective decontamination of the digestive tract in critically ill patients treated in intensive care units: a mixed-methods feasibility study (the SuDDICU study)
Background: Hospital-acquired infections (HAIs) are a major cause of morbidity and mortality. Critically ill patients in intensive care units (ICUs) are particularly susceptible to these infections. One intervention that has gained much attention in reducing HAIs is selective decontamination of the digestive tract (SDD). SDD involves the application of topical non-absorbable antibiotics to the oropharynx and stomach and a short course of intravenous (i.v.) antibiotics. SDD may reduce infections and improve mortality, but has not been widely adopted in the UK or internationally. Hence, there is a need to identify the reasons for low uptake and whether or not further clinical research is needed before wider implementation would be considered appropriate. Objectives: The project objectives were to (1) identify and describe the SDD intervention, (2) identify views about the evidence base, (3) identify acceptability of further research and (4) identify feasibility of further randomised controlled trials (RCTs). Design : A four-stage approach involving (1) case studies of two ICUs in which SDD is delivered including observations, interviews and documentary analysis, (2) a three-round Delphi study for in-depth investigation of clinicians' views, including semi-structured interviews and two iterations of questionnaires with structured feedback, (3) a nationwide online survey of consultants in intensive care medicine and clinical microbiology and (4) semistructured interviews with international clinical triallists to identify the feasibility of further research. Setting : Case studies were set in two UK ICUs. Other stages of this research were conducted by telephone and online with NHS staff working in ICUs. Participants : (1) Staff involved in SDD adoption or delivery in two UK ICUs, (2) ICU experts (intensive care consultants, clinical microbiologists, hospital pharmacists and ICU clinical leads), (3) all intensive care consultants and clinical microbiologists in the UK with responsibility for patients in ICUs were invited and (4) international triallists, selected from their research profiles in intensive care, clinical trials and/or implementation trials. Interventions : SDD involves the application of topical non-absorbable antibiotics to the oropharynx and stomach and a short course of i.v. antibiotics. Main outcome measures: Levels of support for, or opposition to, SDD in UK ICUs; views about the SDD evidence base and about barriers to implementation; and feasibility of further SDD research (e.g. likely participation rates). Results : (1) The two case studies identified complexity in the interplay of clinical and behavioural components of SDD, involving multiple staff. However, from the perspective of individual staff, delivery of SDD was regarded as simple and straightforward. (2) The Delphi study (n = 42) identified (a) specific barriers to SDD implementation, (b) uncertainty about the evidence base and (c) bimodal distributions for key variables, e.g. support for, or opposition to, SDD. (3) The national survey (n = 468) identified uncertainty about the effect of SDD on antimicrobial resistance, infection rates, mortality and cost-effectiveness. Most participants would participate in further SDD research. (4) The triallist interviews (n = 10) focused largely on the substantial challenges of conducting a large, multinational clinical effectiveness trial. Conclusions : There was considerable uncertainty about possible benefits and harms of SDD. Further large-scale clinical effectiveness trials of SDD in ICUs may be required to address these uncertainties, especially relating to antimicrobial resistance. There was a general willingness to participate in a future effectiveness RCT of SDD. However, support was not unanimous. Future research should address the barriers to acceptance and participation in any trial. There was some, but a low level of, interest in adoption of SDD, or studies to encourage implementation of SDD into practice
Priming by Chemokines Restricts Lateral Mobility of the Adhesion Receptor LFA-1 and Restores Adhesion to ICAM-1 Nano-Aggregates on Human Mature Dendritic Cells
LFA-1 is a leukocyte specific β2 integrin that plays a major role in regulating adhesion and migration of different immune cells. Recent data suggest that LFA-1 on mature dendritic cells (mDCs) may function as a chemokine-inducible anchor during homing of DCs through the afferent lymphatics into the lymph nodes, by transiently switching its molecular conformational state. However, the role of LFA-1 mobility in this process is not yet known, despite that the importance of lateral organization and dynamics for LFA-1-mediated adhesion regulation is broadly recognized. Using single particle tracking approaches we here show that LFA-1 exhibits higher mobility on resting mDCs compared to monocytes. Lymphoid chemokine CCL21 stimulation of the LFA-1 high affinity state on mDCs, led to a significant reduction of mobility and an increase on the fraction of stationary receptors, consistent with re-activation of the receptor. Addition of soluble monomeric ICAM-1 in the presence of CCL21 did not alter the diffusion profile of LFA-1 while soluble ICAM-1 nano-aggregates in the presence of CCL21 further reduced LFA-1 mobility and readily bound to the receptor. Overall, our results emphasize the importance of LFA-1 lateral mobility across the membrane on the regulation of integrin activation and its function as adhesion receptor. Importantly, our data show that chemokines alone are not sufficient to trigger the high affinity state of the integrin based on the strict definition that affinity refers to the adhesion capacity of a single receptor to its ligand in solution. Instead our data indicate that nanoclustering of the receptor, induced by multi-ligand binding, is required to maintain stable cell adhesion once LFA-1 high affinity state is transiently triggered by inside-out signals.Peer ReviewedPostprint (published version
Adipocyte-specific protein tyrosine phosphatase 1B deletion increases lipogenesis, adipocyte cell size and is a minor regulator of glucose homeostasis
Peer reviewedPublisher PD
The first report of Gyrodactylus salaris Malmberg, 1957 (Platyhelminthes, Monogenea) on Italian cultured stocks of rainbow trout (Oncorhynchus mykiss Walbaum)
The monogenean Gyrodactylus salons Malmberg, 1957 is considered one of the most important parasites of wild salmonids in the European Community due to the heavy ecological and economical damage it has inflicted on Atlantic salmon (Salmo salar) part populations. Rainbow trout (Oncorhynchus mykiss) is susceptible to G. salaris and can act as a suitable carrier host and, consequently, its trade in EU territory is restricted in relation to the status of "recognized free" zones. Despite the economic importance of rainbow trout farming in Italy, information on the Italian gyrodactylid fauna is lacking and prior to this salons had not been officially reported. During a routine health examination of study farmed rainbow trout stock throughout Central and Northern Italy in 2004-2005, five fish farms were found to be infected with G. salons alongside three other gyrodactylids Morphological and molecular characterisation confirmed the presence of G. salons, Gyrodactylus teuchis Lautraite, Blanc, Thiery, Daniel et Vigneulle, 1999 and Gyrodactylus derjavinoides Malmberg, Collins, Cunningham et Jalah, 2007, while Gyrodactylus truttae Glaser, 1974 was identified by morphological analysis only. The findings from this study extend the distribution of G. salons within Europe and highlight the importance of the rainbow trout trade in its dissemination
Puberty Predicts Approach But Not Avoidance on the Iowa Gambling Task in a Multinational Sample
According to the dual systems model of adolescent risk taking, sensation seeking and impulse control follow different developmental trajectories across adolescence and are governed by two different brain systems. The authors tested whether different underlying processes also drive age differences in reward approach and cost avoidance. Using a modified Iowa Gambling Task in a multinational, cross‐sectional sample of 3,234 adolescents (ages 9–17; M = 12.87, SD = 2.36), pubertal maturation, but not age, predicted reward approach, mediated through higher sensation seeking. In contrast, age, but not pubertal maturation, predicted increased cost avoidance, mediated through greater impulse control. These findings add to evidence that adolescent behavior is best understood as the product of two interacting, but independently developing, brain systems
Enhancement of Naringenin Bioavailability by Complexation with Hydroxypropoyl-β-Cyclodextrin
The abundant flavonoid aglycone, naringenin, which is responsible for the bitter taste in grapefruits, has been shown to possess hypolipidemic and anti-inflammatory effects both in vitro and in vivo. Recently, our group demonstrated that naringenin inhibits hepatitis C virus (HCV) production, while others demonstrated its potential in the treatment of hyperlipidemia and diabetes. However, naringenin suffers from low oral bioavailability critically limiting its clinical potential. In this study, we demonstrate that the solubility of naringenin is enhanced by complexation with β-cyclodextrin, an FDA approved excipient. Hydroxypropoyl-β-cyclodextrin (HPβCD), specifically, increased the solubility of naringenin by over 400-fold, and its transport across a Caco-2 model of the gut epithelium by 11-fold. Complexation of naringenin with HPβCD increased its plasma concentrations when fed to rats, with AUC values increasing by 7.4-fold and Cmax increasing 14.6-fold. Moreover, when the complex was administered just prior to a meal it decreased VLDL levels by 42% and increased the rate of glucose clearance by 64% compared to naringenin alone. These effects correlated with increased expression of the PPAR co-activator, PGC1α in both liver and skeletal muscle. Histology and blood chemistry analysis indicated this route of administration was not associated with damage to the intestine, kidney, or liver. These results suggest that the complexation of naringenin with HPβCD is a viable option for the oral delivery of naringenin as a therapeutic entity with applications in the treatment of dyslipidemia, diabetes, and HCV infection.National Institute of Diabetes and Digestive and Kidney Diseases (U.S.) (K01DK080241)Harvard Clinical Nutrition Research Center (P30-DK040561)European Research Council (Starting Grant (TMIHCV 242699))Massachusetts General Hospital (BioMEMS Resource Center (P41 EB-002503))Alexander Silberman Institute of Life Science
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