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271.
Cooper J. A. Jr; Merrill W. W.; Rankin J. A.; Sibille Y.; Buck M. G. 《Journal of applied physiology》1988,64(4):1615-1623
Airway inflammation is thought to be an important determinant of bronchoconstriction and bronchial hyperreactivity. We have recently demonstrated that bronchoconstriction induced by an aqueous extract of cotton bracts (CBE) is associated with bronchoalveolar complement activation, release of polymorphonuclear neutrophil (PMN) chemoattractants by pulmonary cells, and increased numbers of bronchoalveolar lavage PMN's. In the present study we performed bronchoalveolar lavage (BAL) on subjects after CBE or control (saline) challenge and examined whether BAL cells were activated in vitro to produce other inflammatory agonists. After CBE administration, cultured BAL cells released increased amounts of the reactive O2 species, superoxide (O2-.), and the cyclooxygenase products prostaglandin E2 and thromboxane B2. Although none of these in vitro parameters of BAL cell activation appeared to correlate with the degree of bronchoconstriction induced by CBE, BAL fluid levels of thromboxane B2 were also increased after CBE administration and in vivo amounts of this eicasanoid did correlate with the degree of bronchoconstriction induced by CBE (r = 0.50, P less than 0.04). Finally, although cell culture supernatants were highly chemotactic for PMN's, concentrations of leukotriene B4 were not increased, suggesting other chemotaxins were released by BAL cells in this setting. We conclude that CBE administration activates bronchoalveolar cells to release reactive O2 species and cyclooxygenase products that may be important in the bronchoconstricting response to CBE. 相似文献
272.
273.
Thomas Loyau Sonia Métayer-Coustard Cécile Berri Sabine Crochet Estelle Cailleau-Audouin Mélanie Sannier Pascal Chartrin Christophe Praud Christelle Hennequet-Antier Nicole Rideau Nathalie Couroussé Sandrine Mignon-Grasteau Nadia Everaert Michel Jacques Duclos Shlomo Yahav Sophie Tesseraud Anne Collin 《PloS one》2014,9(9)
274.
Estelle Marion Kevin Carolan Ambroise Adeye Marie Kempf Annick Chauty Laurent Marsollier 《PLoS neglected tropical diseases》2015,9(1)
Nigeria is known to be endemic to Buruli ulcer, but epidemiological data are remarkably rare. Here, we present a large cohort of 127 PCR-confirmed M. ulcerans infection patients coming from Nigeria and treated in a neighbouring country, Benin. Severe lesions and delay of consultation are factors that should encourage establishment of a treatment centre in South Western Nigeria. 相似文献
275.
Allana G. LeBlanc Peter T. Katzmarzyk Tiago V. Barreira Stephanie T. Broyles Jean-Philippe Chaput Timothy S. Church Mikael Fogelholm Deirdre M. Harrington Gang Hu Rebecca Kuriyan Anura Kurpad Estelle V. Lambert Carol Maher José Maia Victor Matsudo Timothy Olds Vincent Onywera Olga L. Sarmiento Martyn Standage Catrine Tudor-Locke Pei Zhao Mark S. Tremblay ISCOLE Research Group 《PloS one》2015,10(6)
Purpose
Previously, studies examining correlates of sedentary behavior have been limited by small sample size, restricted geographic area, and little socio-cultural variability. Further, few studies have examined correlates of total sedentary time (SED) and screen time (ST) in the same population. This study aimed to investigate correlates of SED and ST in children around the world.Methods
The sample included 5,844 children (45.6% boys, mean age = 10.4 years) from study sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Child- and parent-reported behavioral, household, and neighborhood characteristics and directly measured anthropometric and accelerometer data were obtained. Twenty-one potential correlates of SED and ST were examined using multilevel models, adjusting for sex, age, and highest parental education, with school and study site as random effects. Variables that were moderately associated with SED and/or ST in univariate analyses (p<0.10) were included in the final models. Variables that remained significant in the final models (p<0.05) were considered correlates of SED and/or ST.Results
Children averaged 8.6 hours of daily SED, and 54.2% of children failed to meet ST guidelines. In all study sites, boys reported higher ST, were less likely to meet ST guidelines, and had higher BMI z-scores than girls. In 9 of 12 sites, girls engaged in significantly more SED than boys. Common correlates of higher SED and ST included poor weight status, not meeting physical activity guidelines, and having a TV or a computer in the bedroom.Conclusions
In this global sample many common correlates of SED and ST were identified, some of which are easily modifiable (e.g., removing TV from the bedroom), and others that may require more intense behavioral interventions (e.g., increasing physical activity). Future work should incorporate these findings into the development of culturally meaningful public health messages. 相似文献276.
Karine Tréguer Rodolphe Dusaulcy Sandra Grès Estelle Wanecq Philippe Valet Jean Sébastien Saulnier-Blache 《Journal of physiology and biochemistry》2013,69(3):625-632
The objective of the present study was to characterize the nature of the autocrine/paracrine signal within human adipose tissue that may alter glucose metabolism and the inflammatory status in adipocytes. We prepared a conditioned medium from abdominal dermolipectomies in the absence (CM) or the presence (CMBSA) of bovine serum albumin (BSA), and we tested the influence of CM and CMBSA on glucose transport, maximal insulin response, and the expression of inflammation marker genes in differentiated human SGBS adipocytes. We found that CMBSA increased basal and reduced insulin-stimulated glucose incorporation along with a reduced mRNA level of the glucose transport GLUT4, and an increased expression of GLUT1. These effects were associated with a potent upregulation in the mRNA level of the proinflammatory cytokines IL-6 and MCP-1. These regulations were strongly attenuated in the absence of BSA during the preparation of CM, or after BSA depletion of CM, and were attributed to water-soluble molecules rather than lipids. Finally, fractionation of CMBSA by isoelectric focusing showed that part of its bioactivity could be reproduced with proteins with pHi ranging from 6.6 to 7.6. In conclusion, our results demonstrate that the production by human adipose tissue of autocrine/paracrine neutral proteins is able to increase the inflammatory status of the adipocytes and to deteriorate their glucose metabolism and maximal insulin response, and their release is greatly amplified by the presence of albumin. 相似文献
277.
Ale? Pěn?ík Biljana Simonovik Sara V. Petersson Eva Henyková Sibu Simon Kathleen Greenham Yi Zhang Mariusz Kowalczyk Mark Estelle Eva Za?ímalová Ond?ej Novák G?ran Sandberg Karin Ljung 《The Plant cell》2013,25(10):3858-3870
The native auxin, indole-3-acetic acid (IAA), is a major regulator of plant growth and development. Its nonuniform distribution between cells and tissues underlies the spatiotemporal coordination of many developmental events and responses to environmental stimuli. The regulation of auxin gradients and the formation of auxin maxima/minima most likely involve the regulation of both metabolic and transport processes. In this article, we have demonstrated that 2-oxindole-3-acetic acid (oxIAA) is a major primary IAA catabolite formed in Arabidopsis thaliana root tissues. OxIAA had little biological activity and was formed rapidly and irreversibly in response to increases in auxin levels. We further showed that there is cell type–specific regulation of oxIAA levels in the Arabidopsis root apex. We propose that oxIAA is an important element in the regulation of output from auxin gradients and, therefore, in the regulation of auxin homeostasis and response mechanisms. 相似文献
278.
279.
Alban Ziegler Rémi Duclaux-Loras Céline Revenu Fabienne Charbit-Henrion Bernadette Begue Karine Duroure Linda Grimaud Anne Laure Guihot Valérie Desquiret-Dumas Mohammed Zarhrate Nicolas Cagnard Emmanuel Mas Anne Breton Thomas Edouard Clarisse Billon Michael Frank Estelle Colin Guy Lenaers Marianna Parlato 《American journal of human genetics》2021,108(6):1126-1137
280.
Estavillo GM Crisp PA Pornsiriwong W Wirtz M Collinge D Carrie C Giraud E Whelan J David P Javot H Brearley C Hell R Marin E Pogson BJ 《The Plant cell》2011,23(11):3992-4012
Compartmentation of the eukaryotic cell requires a complex set of subcellular messages, including multiple retrograde signals from the chloroplast and mitochondria to the nucleus, to regulate gene expression. Here, we propose that one such signal is a phosphonucleotide (3'-phosphoadenosine 5'-phosphate [PAP]), which accumulates in Arabidopsis thaliana in response to drought and high light (HL) stress and that the enzyme SAL1 regulates its levels by dephosphorylating PAP to AMP. SAL1 accumulates in chloroplasts and mitochondria but not in the cytosol. sal1 mutants accumulate 20-fold more PAP without a marked change in inositol phosphate levels, demonstrating that PAP is a primary in vivo substrate. Significantly, transgenic targeting of SAL1 to either the nucleus or chloroplast of sal1 mutants lowers the total PAP levels and expression of the HL-inducible ASCORBATE PEROXIDASE2 gene. This indicates that PAP must be able to move between cellular compartments. The mode of action for PAP could be inhibition of 5' to 3' exoribonucleases (XRNs), as SAL1 and the nuclear XRNs modulate the expression of a similar subset of HL and drought-inducible genes, sal1 mutants accumulate XRN substrates, and PAP can inhibit yeast (Saccharomyces cerevisiae) XRNs. We propose a SAL1-PAP retrograde pathway that can alter nuclear gene expression during HL and drought stress. 相似文献