The Effects of Prosthesis Inertial Parameters on Inverse Dynamics: A Probabilistic Analysis
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ABSTRACT:
SUBMITTER: Gaffney B
PROVIDER: S-EPMC8597549 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Inhibition of cannabinoid receptor 1 (CB1) has shown efficacy in reducing body weight and improving metabolic parameters, with the effects correlating with target engagement in the brain. Recently, the peripheral effects of inhibiting the CB1 receptor has been appreciated through studies in diet-induced obese and liver-specific CB1 KO mice. In this report, we systematically investigated gene expression changes in peripheral tissues of DIO mice treated with the CB1 inverse agonist AM251. CB1 receptor inhibition led to down-regulation of genes within the de novo fatty acid and cholesterol synthetic pathways, including SREBP-1 and -2, and their downstream targets in both liver and adipose tissue. In addition, genes involved in fatty acid Beta-oxidation were up-regulated with AM251 treatment, probably through the activation of PPARalpha. In adipose tissue, CB1 receptor inhibition led to the down-regulation of genes in the TNFalpha signal transduction pathway and possibly to the activation of PPARgamma, both of which would result in improved insulin sensitivity. CB1-/- mice were obtained from A. Zimmer (University of Bonn) (Zimmer et al., 1999) and back-crossed onto C57BL/6J genetic background for ten generations by A. Zimmer before homozygous CB1-/- mice were re-derived at Taconic Farms (German Town, NY) onto the C57BL/6N genetic background. Male CB1-/- mice and control littermates (n=5-7 in each group) at 2 months of age were fed with regular chow (Teklad 7012, 13 % kcal from fat, 3.41 kcal/g, Harlan Laboratories, Indianapolis, IN, USA) or high fat diet (S3282, 59.4% kcal from fat; 24.5% kcal from carbohydrate; 16.2% kcal from protein; 5.29 kcal/g, Bio-Serv, Frenchtown, NJ, USA) for 14 weeks, and were individually caged 1 week before drug treatment. Vehicle (0.5% methylcellulose) or AM251 (10 mg/kg, Sigma, St Louis, MO, USA) were dosed by oral gavage at 5:00 PM daily for 2 days. Body weight was measured at 5:00 PM on day 1 and 2, and at 10:00 AM on day 3 before tissue collection. Food was measured at 5:00 PM on day 1 and at 10:00 AM on day 3 before tissue collection. Food intake is calculated as the difference in food weight at the start minus at the end of the study. Mice were euthanized by CO2 asphyxiation at 10:00 AM following the second dose.
2010-06-21 | E-GEOD-21069 | biostudies-arrayexpress
Project description:Inhibition of cannabinoid receptor 1 (CB1) has shown efficacy in reducing body weight and improving metabolic parameters, with the effects correlating with target engagement in the brain. Recently, the peripheral effects of inhibiting the CB1 receptor has been appreciated through studies in diet-induced obese and liver-specific CB1 KO mice. In this report, we systematically investigated gene expression changes in peripheral tissues of DIO mice treated with the CB1 inverse agonist AM251. CB1 receptor inhibition led to down-regulation of genes within the de novo fatty acid and cholesterol synthetic pathways, including SREBP-1 and -2, and their downstream targets in both liver and adipose tissue. In addition, genes involved in fatty acid Beta-oxidation were up-regulated with AM251 treatment, probably through the activation of PPARalpha. In adipose tissue, CB1 receptor inhibition led to the down-regulation of genes in the TNFalpha signal transduction pathway and possibly to the activation of PPARgamma, both of which would result in improved insulin sensitivity.
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Project description:BackgroundRecent advances and automation in DNA sequencing technology has created a vast amount of DNA sequence data. This increasing growth of sequence data demands better and efficient analysis methods. Identifying genes in this newly accumulated data is an important issue in bioinformatics, and it requires the prediction of the complete gene structure. Accurate identification of splice sites in DNA sequences plays one of the central roles of gene structural prediction in eukaryotes. Effective detection of splice sites requires the knowledge of characteristics, dependencies, and relationship of nucleotides in the splice site surrounding region. A higher-order Markov model is generally regarded as a useful technique for modeling higher-order dependencies. However, their implementation requires estimating a large number of parameters, which is computationally expensive.ResultsThe proposed method for splice site detection consists of two stages: a first order Markov model (MM1) is used in the first stage and a support vector machine (SVM) with polynomial kernel is used in the second stage. The MM1 serves as a pre-processing step for the SVM and takes DNA sequences as its input. It models the compositional features and dependencies of nucleotides in terms of probabilistic parameters around splice site regions. The probabilistic parameters are then fed into the SVM, which combines them nonlinearly to predict splice sites. When the proposed MM1-SVM model is compared with other existing standard splice site detection methods, it shows a superior performance in all the cases.ConclusionWe proposed an effective pre-processing scheme for the SVM and applied it for the identification of splice sites. This is a simple yet effective splice site detection method, which shows a better classification accuracy and computational speed than some other more complex methods.
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