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991.
Jessica Lebenberg Alain Lalande Patrick Clarysse Irene Buvat Christopher Casta Alexandre Cochet Constantin Constantinidès Jean Cousty Alain de Cesare Stephanie Jehan-Besson Muriel Lefort Laurent Najman Elodie Roullot Laurent Sarry Christophe Tilmant Frederique Frouin Mireille Garreau 《PloS one》2015,10(8)
This work aimed at combining different segmentation approaches to produce a robust and accurate segmentation result. Three to five segmentation results of the left ventricle were combined using the STAPLE algorithm and the reliability of the resulting segmentation was evaluated in comparison with the result of each individual segmentation method. This comparison was performed using a supervised approach based on a reference method. Then, we used an unsupervised statistical evaluation, the extended Regression Without Truth (eRWT) that ranks different methods according to their accuracy in estimating a specific biomarker in a population. The segmentation accuracy was evaluated by estimating six cardiac function parameters resulting from the left ventricle contour delineation using a public cardiac cine MRI database. Eight different segmentation methods, including three expert delineations and five automated methods, were considered, and sixteen combinations of the automated methods using STAPLE were investigated. The supervised and unsupervised evaluations demonstrated that in most cases, STAPLE results provided better estimates than individual automated segmentation methods. Overall, combining different automated segmentation methods improved the reliability of the segmentation result compared to that obtained using an individual method and could achieve the accuracy of an expert. 相似文献
992.
Peter von Dassow Uwe John Hiroyuki Ogata Ian Probert El Mahdi Bendif Jessica U Kegel Stéphane Audic Patrick Wincker Corinne Da Silva Jean-Michel Claverie Scott Doney David M Glover Daniella Mella Flores Yeritza Herrera Magali Lescot Marie-José Garet-Delmas Colomban de Vargas 《The ISME journal》2015,9(6):1365-1377
Emiliania huxleyi is the most abundant calcifying plankton in modern oceans with substantial intraspecific genome variability and a biphasic life cycle involving sexual alternation between calcified 2N and flagellated 1N cells. We show that high genome content variability in Emiliania relates to erosion of 1N-specific genes and loss of the ability to form flagellated cells. Analysis of 185 E. huxleyi strains isolated from world oceans suggests that loss of flagella occurred independently in lineages inhabiting oligotrophic open oceans over short evolutionary timescales. This environmentally linked physiogenomic change suggests life cycling is not advantageous in very large/diluted populations experiencing low biotic pressure and low ecological variability. Gene loss did not appear to reflect pressure for genome streamlining in oligotrophic oceans as previously observed in picoplankton. Life-cycle modifications might be common in plankton and cause major functional variability to be hidden from traditional taxonomic or molecular markers. 相似文献
993.
Etiological overlap between obsessive‐compulsive disorder and anorexia nervosa: a longitudinal cohort,multigenerational family and twin study
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Martin Cederlöf Laura M. Thornton Jessica Baker Paul Lichtenstein Henrik Larsson Christian Rück Cynthia M. Bulik David Mataix‐Cols 《World psychiatry》2015,14(3):333-338
Obsessive‐compulsive disorder (OCD) often co‐occurs with anorexia nervosa (AN), a comorbid profile that complicates the clinical management of both conditions. This population‐based study aimed to examine patterns of comorbidity, longitudinal risks, shared familial risks and shared genetic factors between OCD and AN at the population level. Participants were individuals with a diagnosis of OCD (N=19,814) or AN (N=8,462) in the Swedish National Patient Register between January 1992 and December 2009; their first‐, second‐ and third‐degree relatives; and population‐matched (1:10 ratio) unaffected comparison individuals and their relatives. Female twins from the population‐based Swedish Twin Register (N=8,550) were also included. Females with OCD had a 16‐fold increased risk of having a comorbid diagnosis of AN, whereas males with OCD had a 37‐fold increased risk. Longitudinal analyses showed that individuals first diagnosed with OCD had an increased risk for a later diagnosis of AN (risk ratio, RR=3.6), whereas individuals first diagnosed with AN had an even greater risk for a later diagnosis of OCD (RR=9.6). These longitudinal risks were about twice as high for males than for females. First‐ and second‐degree relatives of probands with OCD had an increased risk for AN, and the magnitude of this risk tended to increase with the degree of genetic relatedness. Bivariate twin models revealed a moderate but significant degree of genetic overlap between self‐reported OCD and AN diagnoses (ra=0.52, 95% CI: 0.26‐0.81), but most of the genetic variance was disorder‐specific. The moderately high genetic correlation supports the idea that this frequently observed comorbid pattern is at least in part due to shared genetic factors, though disorder‐specific factors are more important. These results have implications for current gene‐searching efforts and for clinical practice. 相似文献
994.
995.
Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution
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Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage, and mate choice and have played important roles in speciation. Here, we review studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post‐embryonic, peripheral nerve‐associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow‐orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns. 相似文献
996.
Juliane Dinter Jessica Mühlhaus Carolin Leonie Wienchol Chun-Xia Yi Daniela Nürnberg Silke Morin Annette Grüters Josef K?hrle Torsten Sch?neberg Matthias Tsch?p Heiko Krude Gunnar Kleinau Heike Biebermann 《PloS one》2015,10(2)
ObjectiveApplication of 3-iodothyronamine (3-T1AM) results in decreased body temperature and body weight in rodents. The trace amine-associated receptor (TAAR) 1, a family A G protein-coupled receptor, is a target of 3-T1AM. However, 3-T1AM effects still persist in mTaar1 knockout mice, which suggest so far unknown further receptor targets that are of physiological relevance. TAAR5 is a highly conserved TAAR subtype among mammals and we here tested TAAR5 as a potential 3-T1AM target. First, we investigated mouse Taar5 (mTaar5) expression in several brain regions of the mouse in comparison to mTaar1. Secondly, to unravel the full spectrum of signaling capacities, we examined the distinct Gs-, Gi/o-, G12/13-, Gq/11- and MAP kinase-mediated signaling pathways of mouse and human TAAR5 under ligand-independent conditions and after application of 3-T1AM. We found overlapping localization of mTaar1 and mTaar5 in the amygdala and ventromedial hypothalamus of the mouse brain. Second, the murine and human TAAR5 (hTAAR5) display significant basal activity in the Gq/11 pathway but show differences in the basal activity in Gs and MAP kinase signaling. In contrast to mTaar5, 3-T1AM application at hTAAR5 resulted in significant reduction in basal IP3 formation and MAP kinase signaling. In conclusion, our data suggest that the human TAAR5 is a target for 3-T1AM, exhibiting inhibitory effects on IP3 formation and MAP kinase signaling pathways, but does not mediate Gs signaling effects as observed for TAAR1. This study also indicates differences between TAAR5 orthologs with respect to their signaling profile. In consequence, 3-T1AM-mediated effects may differ between rodents and humans. 相似文献
997.
998.
Weight change in the first 2 months of a lifestyle intervention predicts weight changes 8 years later
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999.
Blunted suppression of acyl‐ghrelin in response to fructose ingestion in obese adolescents: The role of insulin resistance
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