679 research outputs found

    Foreword

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    Myristic acid potentiates palmitic acid-induced lipotoxicity and steatohepatitis associated with lipodystrophy by sustaning de novo ceramide synthesis.

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    Palmitic acid (PA) induces hepatocyte apoptosis and fuels de novo ceramide synthesis in the endoplasmic reticulum (ER). Myristic acid (MA), a free fatty acid highly abundant in copra/palmist oils, is a predictor of nonalcoholic steatohepatitis (NASH) and stimulates ceramide synthesis. Here we investigated the synergism between MA and PA in ceramide synthesis, ER stress, lipotoxicity and NASH. Unlike PA, MA is not lipotoxic but potentiated PA-mediated lipoapoptosis, ER stress, caspase-3 activation and cytochrome c release in primary mouse hepatocytes (PMH). Moreover, MA kinetically sustained PA-induced total ceramide content by stimulating dehydroceramide desaturase and switched the ceramide profile from decreased to increased ceramide 14:0/ceramide16:0, without changing medium and long-chain ceramide species. PMH were more sensitive to equimolar ceramide14:0/ceramide16:0 exposure, which mimics the outcome of PA plus MA treatment on ceramide homeostasis, than to either ceramide alone. Treatment with myriocin to inhibit ceramide synthesis and tauroursodeoxycholic acid to prevent ER stress ameliorated PA plus MA induced apoptosis, similar to the protection afforded by the antioxidant BHA, the pan-caspase inhibitor z-VAD-Fmk and JNK inhibition. Moreover, ruthenium red protected PMH against PA and MA-induced cell death. Recapitulating in vitro findings, mice fed a diet enriched in PA plus MA exhibited lipodystrophy, hepatosplenomegaly, increased liver ceramide content and cholesterol levels, ER stress, liver damage, inflammation and fibrosis compared to mice fed diets enriched in PA or MA alone. The deleterious effects of PA plus MA-enriched diet were largely prevented by in vivo myriocin treatment. These findings indicate a causal link between ceramide synthesis and ER stress in lipotoxicity, and imply that the consumption of diets enriched in MA and PA can cause NASH associated with lipodystrophy

    Hidromedusas profundas del Mediterráneo: Un estudio que incluye la descripción de dos nuevas especies recolectadas en cañones submarinos del Mediterráneo Occidental

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    Two new species of hydromedusae (Foersteria antoniae and Cunina simplex) are described from plankton collected in sediment traps placed in the Lacaze-Duthiers Submarine Canyon and along Banyuls-sur-Mer coast (northwestern Mediterranean). The Mediterranean hydromedusan deep-water fauna contains 41 species which represent 45.5 % of the world-wide deep-sea hydromedusae fauna (90) and 20% of the total number of Mediterranean hydromedusae (204). The Mediterranean deep-water hydromedusan fauna is characterised by a large percentage of holoplanktonic species (61%), mainly Trachymedusae. Nevertheless, contrary to the general opinion, the percentage of meroplanktonic species is equally high. The most original features of this fauna lies however in the importance of the number of endemic species (22%) and in the fact that the majority of them are meroplanktonic Leptomedusae with a supposed bathybenthic stage. Some of the endemic species could still represent relics of the primitive Tethys fauna having survived to the Messinian crisis. The origin of the Mediterranean deep-water hydromedusan fauna is discussed and a general hypothesis is proposed.Se describen dos especies nuevas a partir de ejemplares recolectados mediante trampas de sedimento del cañón submarino de Lacaze-Duthiers situado en frente de la costa de Banyuls-sur-Mer (Mediterráneo noroccidental). La fauna profunda de hydromedusas en el Mediterráneo contiene 41 especies que representan 45.5 % de la fauna mundial del grupo y el 20% de la fauna de hydromedusas del Mediterráneo. La fauna Mediterránea de hydromedusas profundas se caracteriza por un gran porcentaje de especies holoplanctónicas (61%), fundamentalmente Trachymedusas, sin embargo, contrario a la opinión generalizada, el porcentaje de especies meroplanctónicas es igualmente importante (39%). La característica más interesante de esta fauna es el número de especies endémicas (22%) y el hecho de que la mayoría de estas especies son meroplanctónicas (Leptomedusas) con una supuesta fase bentónica. Algunas de estas especies endémicas, podrían ser especies relictas (endémica insular) de la fauna primitiva del Tetis que sobrevivieron a la crisis Mesiniana. Se discute el origen de la fauna de hydromedusas profundas en el Mediterráneo y se presenta una nueva hipótesis

    Validation of the Spanish version of the Multidimensional State Boredom Scale (MSBS)

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    Background: Boredom, which is a common problem in the general population, has been associated with several psychiatric disorders. The Multidimensional State Boredom Scale (MSBS) was developed, based on a theoretically and empirically grounded definition of boredom, to assess this construct. The aim of the present study was to assess the psychometric properties of the Spanish validated version of the MSBS in a multi-age sample recruited from the general population. Methods: The patients (N = 303) were recruited from primary care settings. In addition to the sociodemographic variables and the MSBS, the General Health Questionnaire 28 items (GHQ-28), Positive and Negative Affect Scale (PANAS), Negative subscale and the Mindful Attention Awareness Scale (MAAS) were administered. We used confirmatory factor analysis (CFA) to analyse the dimensionality of the MSBS. Cronbach’s a coefficient was used to analyse the internal consistency of the scale. The consistency of the MSBS over time (test-retest reliability) was assessed using the intra-class correlation coefficient. The construct validity was examined by calculating Pearson’s r correlations between the MSBS with theoretically related and unrelated constructs. Cronbach’s a for MSBS was 0.89 (95 % CI, 0.87–0.92), ranging from 0.75 to 0.83 for the 5 subscales. Results: The characteristics of the final sample (N = 303) were that the participants were primarily female (66.77 %) with a mean age of 49.32 years (SD, 11.46) and primarily European (94.71 %). The CFA of the MSBS confirmed that the original five-factor model showed good fit indices: CFI = .96; GFI = .94; SRMR = .05; and RMSEA = .06 [.05–.08]. Cronbach’s a for MSBS was 0.89 (95 % CI, 0.87–0.92), ranging from 0.75 to 0.83 for the 5 subscales. The MSBS showed a test-retest coefficient measured with an ICC of 0.90 (95 % CI, 0.88–0.92). The ICC for the 5 subscales ranged from 0.81 to 0.89. The MSBS showed a significant negative correlation with MAAS and a significant positive correlation with the GHQ (total score and subscales) and PANAS-Negative Affect. Conclusions: The Spanish version of the MSBS has been validated as a reliable instrument for measuring boredom in the general population. This study will facilitate the assessment of boredom for clinical and research purposes in Spanish-speaking populations
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