382 research outputs found
Examining exercise dependence symptomatology from a self-determination perspective
Background: Based on the theoretical propositions of Self-Determination Theory (SDT; Deci & Ryan, 1985) this study examined whether individuals classified as “nondependent-symptomatic” and “nondependent-asymptomatic” for exercise dependence differed in terms of the level of exercise-related psychological need satisfaction and self-determined versus controlling motivation they reported. Further, we examined if the type of motivational regulations predicting exercise behaviour differed among these groups.
Methods: Participants (N = 339), recruited from fitness, community, and retail settings, completed measures of exercise-specific psychological need satisfaction, motivational regulations, exercise behaviour and exercise dependence.
Results: Individuals who were nondependent-symptomatic for exercise dependence reported higher levels of competence need satisfaction and all forms of motivational regulation, compared to nondependent-asymptomatic individuals. Introjected regulation approached significance as a positive predictor of strenuous exercise behaviour for symptomatic individuals. Identified regulation was a positive predictor of strenuous exercise for asymptomatic individuals.
Conclusions: The findings reinforce the applicability of SDT to understanding engagement in exercise
Part 4: Pediatric basic and advanced life support 2020 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care
International Coercion, Emulation and Policy Diffusion: Market-Oriented Infrastructure Reforms, 1977-1999
Why do some countries adopt market-oriented reforms such as deregulation, privatization and liberalization of competition in their infrastructure industries while others do not? Why did the pace of adoption accelerate in the 1990s? Building on neo-institutional theory in sociology, we argue that the domestic adoption of market-oriented reforms is strongly influenced by international pressures of coercion and emulation. We find robust support for these arguments with an event-history analysis of the determinants of reform in the telecommunications and electricity sectors of as many as 205 countries and territories between 1977 and 1999. Our results also suggest that the coercive effect of multilateral lending from the IMF, the World Bank or Regional Development Banks is increasing over time, a finding that is consistent with anecdotal evidence that multilateral organizations have broadened the scope of the “conditionality” terms specifying market-oriented reforms imposed on borrowing countries. We discuss the possibility that, by pressuring countries into policy reform, cross-national coercion and emulation may not produce ideal outcomes.http://deepblue.lib.umich.edu/bitstream/2027.42/40099/3/wp713.pd
Diversity in Functional Organization of Class I and Class II Biotin Protein Ligase
The cell envelope of Mycobacterium tuberculosis
(M.tuberculosis) is composed of a variety of lipids
including mycolic acids, sulpholipids, lipoarabinomannans, etc., which impart
rigidity crucial for its survival and pathogenesis. Acyl CoA carboxylase (ACC)
provides malonyl-CoA and methylmalonyl-CoA, committed precursors for fatty acid
and essential for mycolic acid synthesis respectively. Biotin Protein Ligase
(BPL/BirA) activates apo-biotin carboxyl carrier protein (BCCP) by biotinylating
it to an active holo-BCCP. A minimal peptide (Schatz), an efficient substrate
for Escherichia coli BirA, failed to serve as substrate for
M. tuberculosis Biotin Protein Ligase
(MtBPL). MtBPL specifically biotinylates
homologous BCCP domain, MtBCCP87, but not
EcBCCP87. This is a unique feature of
MtBPL as EcBirA lacks such a stringent
substrate specificity. This feature is also reflected in the lack of
self/promiscuous biotinylation by MtBPL. The N-terminus/HTH
domain of EcBirA has the self-biotinable lysine residue that is
inhibited in the presence of Schatz peptide, a peptide designed to act as a
universal acceptor for EcBirA. This suggests that when biotin
is limiting, EcBirA preferentially catalyzes, biotinylation of
BCCP over self-biotinylation. R118G mutant of EcBirA showed
enhanced self and promiscuous biotinylation but its homologue, R69A
MtBPL did not exhibit these properties. The catalytic
domain of MtBPL was characterized further by limited
proteolysis. Holo-MtBPL is protected from proteolysis by
biotinyl-5′ AMP, an intermediate of MtBPL catalyzed
reaction. In contrast, apo-MtBPL is completely digested by
trypsin within 20 min of co-incubation. Substrate selectivity and inability to
promote self biotinylation are exquisite features of MtBPL and
are a consequence of the unique molecular mechanism of an enzyme adapted for the
high turnover of fatty acid biosynthesis
RNA-Seq Reveals an Integrated Immune Response in Nucleated Erythrocytes
Background: Throughout the primary literature and within textbooks, the erythrocyte has been tacitly accepted to have maintained a unique physiological role; namely gas transport and exchange. In non-mammalian vertebrates, nucleated erythrocytes are present in circulation throughout the life cycle and a fragmented series of observations in mammals support a potential role in non-respiratory biological processes. We hypothesised that nucleated erythrocytes could actively participate via ligand-induced transcriptional re-programming in the immune response. Methodology/Principal Findings: Nucleated erythrocytes from both fish and birds express and regulate specific pattern recognition receptor (PRR) mRNAs and, thus, are capable of specific pathogen associated molecular pattern (PAMP) detection that is central to the innate immune response. In vitro challenge with diverse PAMPs led to de novo specific mRNA synthesis of both receptors and response factors including interferon-alpha (IFNα) that exhibit a stimulus-specific polysomal shift supporting active translation. RNA-Seq analysis of the PAMP (Poly (I:C), polyinosinic:polycytidylic acid)-erythrocyte response uncovered diverse cohorts of differentially expressed mRNA transcripts related to multiple physiological systems including the endocrine, reproductive and immune. Moreover, erythrocyte-derived conditioned mediums induced a type-1 interferon response in macrophages thus supporting an integrative role for the erythrocytes in the immune response. Conclusions/Significance: We demonstrate that nucleated erythrocytes in non-mammalian vertebrates spanning significant phylogenetic distance participate in the immune response. RNA-Seq studies highlight a mRNA repertoire that suggests a previously unrecognized integrative role for the erythrocytes in other physiological systems
Analysis of Rabies in China: Transmission Dynamics and Control
Human rabies is one of the major public-health problems in China. The number of human rabies cases has increased dramatically in the last 15 years, partially due to the poor understanding of the transmission dynamics of rabies and the lack of effective control measures of the disease. In this article, in order to explore effective control and prevention measures we propose a deterministic model to study the transmission dynamics of rabies in China. The model consists of susceptible, exposed, infectious, and recovered subpopulations of both dogs and humans and describes the spread of rabies among dogs and from infectious dogs to humans. The model simulations agree with the human rabies data reported by the Chinese Ministry of Health. We estimate that the basic reproduction number for the rabies transmission in China and predict that the number of the human rabies is decreasing but may reach another peak around 2030. We also perform some sensitivity analysis of in terms of the model parameters and compare the effects of culling and immunization of dogs. Our study demonstrates that (i) reducing dog birth rate and increasing dog immunization coverage rate are the most effective methods for controlling rabies in China; and (ii) large scale culling of susceptible dogs can be replaced by immunization of them
Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context
Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts
Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas
Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing
molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images
Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images
of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL
maps are derived through computational staining using a convolutional neural network trained to
classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and
correlation with overall survival. TIL map structural patterns were grouped using standard
histopathological parameters. These patterns are enriched in particular T cell subpopulations
derived from molecular measures. TIL densities and spatial structure were differentially enriched
among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial
infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic
patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for
the TCGA image archives with insights into the tumor-immune microenvironment
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