Follow the metaplasia: Characteristics and oncogenic implications of metaplasia\u27s pattern of spread throughout the stomach

The human stomach functions as both a digestive and innate immune organ. Its main product, acid, rapidly breaks down ingested products and equally serves as a highly effective microbial filter. The gastric epithelium has evolved mechanisms to appropriately handle the myriad of injurious substances, both exogenous and endogenous, to maintain the epithelial barrier and restore homeostasis. The most significant chronic insult that the stomach must face i

KAT2A and KAT2B prevent double-stranded RNA accumulation and interferon signaling to maintain intestinal stem cell renewal

Histone acetyltransferase

Colour Evolution of Rosé Wines after Bottling

This research reports on the colour evolution of six rosé wines during sixteen months of storage in the bottle.Colour changes were determined in terms of CIELAB colour parameters and in terms of the common colourcategories used in visual assessment. The colour measurement method reproduces the visual assessmentconditions during wine tasting with respect to wine sampler, illuminating source, observing background andsample-observer geometry. CIELAB L*, a*, b*, C* and hab colour coordinates were determined at seven differenttimes (t = 0, 20, 80, 153, 217, 300 and 473 days). The time evolution of colour coordinate values was studied usingmodels related to linear, quadratic and exponential rise to a maximum. Adjusted R2, average standard error andCIELAB ΔE* colour difference were used to compare models and evaluate their performance. For each colourcoordinate, the accuracy of model predictions was similar to the standard deviation associated with a singlemeasurement. An average ΔE* = 0.92 with a 90 percentile value ΔE*90% = 1.50 was obtained between measuredand predicted colour. These values are smaller than human colour discrimination thresholds. The classificationinto colour categories at different times depends on the wine sample. It was found that all wines take three tofour months to change from raspberry to strawberry colour and seven to eight months to reach the redcurrantcategory. Only two wines had developed salmon colour by the end of the experiment

Analysis of polymeric phenolics in red wines using different techniques combined with gel permeation chromatography fractionation

A multiple-step analytical method was developed to improve the analysis of polymeric phenolics in red wines. With a common initial step based on the fractionation of wine phenolics by gel permeation chromatography (GPC), different analytical techniques were used: high-performance liquid chromatography-diode array detection (HPLC-DAD), HPLC-mass spectrometry (MS), capillary zone electrophoresis (CZE) and spectrophotometry. This method proved to be valid for analyzing different families of phenolic compounds, such as monomeric phenolics and their derivatives, polymeric pigments and proanthocyanidins. The analytical characteristics of fractionation by GPC were studied and the method was fully validated, yielding satisfactory statistical results. GPC fractionation substantially improved the analysis of polymeric pigments by CZE, in terms of response, repeatability and reproducibility. It also represented an improvement in the traditional vanillin assay used for proanthocyanidin (PA) quantification. Astringent proanthocyanidins were also analyzed using a simple combined method that allowed these compounds, for which only general indexes were available, to be quantified. © 2005 Elsevier B.V. All rights reserved

Regulation of the double-stranded RNA response through ADAR1 licenses metaplastic reprogramming in gastric epithelium

Cells recognize both foreign and host-derived double-stranded RNA (dsRNA) via a signaling pathway that is usually studied in the context of viral infection. It has become increasingly clear that the sensing and handling of endogenous dsRNA is also critical for cellular differentiation and development. The adenosine RNA deaminase, ADAR1, has been implicated as a central regulator of the dsRNA response, but how regulation of the dsRNA response might mediate cell fate during injury and whether such signaling is cell intrinsic remain unclear. Here, we show that the ADAR1-mediated response to dsRNA was dramatically induced in 2 distinct injury models of gastric metaplasia. Mouse organoid and in vivo genetic models showed that ADAR1 coordinated a cell-intrinsic, epithelium-autonomous, and interferon signaling-independent dsRNA response. In addition, dsRNA accumulated within a differentiated epithelial population (chief cells) in mouse and human stomachs as these cells reprogrammed to a proliferative, reparative (metaplastic) state. Finally, chief cells required ADAR1 to reenter the cell cycle during metaplasia. Thus, cell-intrinsic ADAR1 signaling is critical for the induction of metaplasia. Because metaplasia increases cancer risk, these findings support roles for ADAR1 and the response to dsRNA in oncogenesis

Expression of the small T antigen of Lymphotropic Papovavirus is sufficient to transform primary mouse embryo fibroblasts

AbstractPolyomaviruses induce cell proliferation and transformation through different oncoproteins encoded within the early region (ER): large T antigen (LT), small T antigen (sT) and, in some cases, additional components. Each virus utilizes different mechanisms to achieve transformation. For instance, the LTs of Simian virus 40 (SV40), BK and/or JC virus can induce transformation; but Merkel Cell Polyomavirus (MCPyV) requires expression of sT. Lymphotropic Papovavirus (LPV) is closely related to Human Polyomavirus 9 (HuPyV9) and, under similar conditions, mice expressing LPV.ER exhibit higher rates of tumor formation than mice expressing SV40.ER. We have investigated the contributions of individual LPV.ER components to cell transformation. In contrast to SV40, LPV.ER transforms mouse embryonic fibroblasts (MEFs), but expression of LPV LT is insufficient to transform MEFs. Furthermore, LPV sT induces immortalization and transformation of MEFs. Thus, in the case of LPV, sT is the main mediator of oncogenesis

Nontangential limits and Fatou-type theorems on post-critically finite self-similar sets

In this paper we study the boundary limit properties of harmonic functions on $\mathbb R_+\times K$, the solutions $u(t,x)$ to the Poisson equation $$\frac{\partial^2 u}{\partial t^2} + \Delta u = 0,$$ where $K$ is a p.c.f. set and $\Delta$ its Laplacian given by a regular harmonic structure. In particular, we prove the existence of nontangential limits of the corresponding Poisson integrals, and the analogous results of the classical Fatou theorems for bounded and nontangentially bounded harmonic functions.Comment: 22 page

Motivational analysis comparing three contexts of physical activity

El estudio analizó las diferencias motivacionales entre estudiantes de educación física, deportistas y practicantes de ejercicio físico no competitivo. Además, examinó el poder de predicción del clima motivacional percibido y de los tipos de motivación sobre la propensión a la experiencia autotélica en los tres contextos. Se utilizaron tres muestras diferentes: 895 estudiantes de educación física, 413 deportistas y 727 practicantes de ejercicio físico no competitivo. El análisis de regresión mostró que el clima tarea y la motivación intrínseca predijeron positivamente y de forma significativa la experiencia autotélica en los tres contextos, de ahí la importancia de fomentar este tipo de clima motivacional. No obstante, los resultados han mostrado diferencias motivacionales entre los contextos de educación física, deporte competitivo y ejercicio físico no competitivo. Los resultados son discutidos en relación al diferente carácter competitivo/lúdico y voluntariedad/obligatoriedad que rodea a la práctica física en cada uno de los contextos comparados en este estudioThe study analyzed the motivational differences between physical education students, athletes and non-competitive exercisers. Furthermore, the predictive power of perceived motivational climate and types of motivation on the autotelic experience propensity in the three contexts was examined. Three different samples were used: 895 physical education students, 413 athletes and 727 non-competitive exercisers. Regression analysis showed that task-involving climate and intrinsic motivation positively and significantly predicted the autotelic experience in the three contexts, hence the importance of promoting this type of motivational climate. However, the results revealed that there were motivational differences between the contexts of physical education, competitive sports and non-competitive exercise. The results are discussed in relation to the different features (e.g. competitive, recreational, voluntary or obligatory) surrounding the physical activity in each of the contexts compared in this studyLa realización de este trabajo fue posible gracias al proyecto de investigación "Evaluación y análisis comparativo de factores motivacionales relacionados con la adherencia a la práctica en diferentes contextos físico-deportivos: Educación física, deporte de competición y actividad física no competitiva" (Ref. DEP2007-73201-C03/ACTI), financiado por el Ministerio de Ciencia e Innovación de Españ

Community College Student Engagement Patterns: A Typology Revealed Through Exploratory Cluster Analysis

This study employs survey data from the Center for Community College Student Engagement to examine the similarities and differences that exist across student-level domains in terms of student engagement in community colleges. In total, the sample used in the analysis pools data from 663 community colleges and includes more than 320,000 students. Using data-mining techniques to discover a parsimonious number of natural clusters and, in turn, a k-means cluster analysis as a means of revealing a naturally occurring typology of engagement patterns, our findings reveal that support service utilization is the most distinguishing feature of the similarities and dissimilarities across student groups, suggesting areas for further theory development and testing

Community College Student Engagement Patterns: A Typology Revealed Through Exploratory Cluster Analysis

This study employs survey data from the Center for Community College Student Engagement to examine the similarities and differences that exist across student-level domains in terms of student engagement in community colleges. In total, the sample used in the analysis pools data from 663 community colleges and includes more than 320,000 students. Using data-mining techniques to discover a parsimonious number of natural clusters and, in turn, a k-means cluster analysis as a means of revealing a naturally occurring typology of engagement patterns, our findings reveal that support service utilization is the most distinguishing feature of the similarities and dissimilarities across student groups, suggesting areas for further theory development and testing