Université de Sherbrooke

About: Université de Sherbrooke is a education organization based out in Sherbrooke, Quebec, Canada. It is known for research contribution in the topics: Population & Receptor. The organization has 14922 authors who have published 28783 publications receiving 792511 citations. The organization is also known as: Universite de Sherbrooke & Sherbrooke University.

From "truly naïve" to "exhausted senescent" T cells: when markers predict functionality.

Abstract: The study of T cell biology has been accelerated by substantial progress at the technological level, particularly through the continuing advancement of flow cytometry. The conventional approach of observing T cells as either T helper or T cytotoxic is overly simplistic and does not allow investigators to clearly identify immune mechanisms or alterations in physiological processes that impact on clinical outcomes. The complexity of T cell sub-populations, as we understand them today, combined with the immunological and functional diversity of these subsets represent significant complications for the study of T cell biology. In this article, we review the use of classical markers in delineating T cell sub-populations, from "truly naive" T cells (recent thymic emigrants with no proliferative history) to "exhausted senescent" T cells (poorly proliferative cells that display severe functional abnormalities) wherein the different phenotypes of these populations reflect their disparate functionalities. In addition, since persistent infections and chronological aging have been shown to be associated with significant alterations in human T cell distribution and function, we also discuss age-associated and cytomegalovirus-driven alterations in the expression of key subset markers.

Mechanisms of the free fatty acid-induced increase in hepatic glucose production

Abstract: The associations between obesity, insulin resistance, and type 2 diabetes mellitus are well documented. Free fatty acids (FFA), which are often elevated in obesity, have been implicated as an important link in these associations. Contrary to muscle glucose metabolism, the effects of FFA on hepatic glucose metabolism and the associated mechanisms have not been extensively investigated. It is still controversial whether FFA have substantial effects on hepatic glucose production, and the mechanisms responsible for these putative effects remain unknown. We review recent progress in this area and try to clarify controversial issues regarding the mechanisms responsible for the FFA-induced increase in hepatic glucose production in the postabsorptive state and during hyperinsulinemia.

A Neural Autoregressive Topic Model

Abstract: We describe a new model for learning meaningful representations of text documents from an unlabeled collection of documents. This model is inspired by the recently proposed Replicated Softmax, an undirected graphical model of word counts that was shown to learn a better generative model and more meaningful document representations. Specifically, we take inspiration from the conditional mean-field recursive equations of the Replicated Softmax in order to define a neural network architecture that estimates the probability of observing a new word in a given document given the previously observed words. This paradigm also allows us to replace the expensive softmax distribution over words with a hierarchical distribution over paths in a binary tree of words. The end result is a model whose training complexity scales logarithmically with the vocabulary size instead of linearly as in the Replicated Softmax. Our experiments show that our model is competitive both as a generative model of documents and as a document representation learning algorithm.