24 research outputs found

    Quantitative modeling of the physiology of ascites in portal hypertension

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    Although the factors involved in cirrhotic ascites have been studied for a century, a number of observations are not understood, including the action of diuretics in the treatment of ascites and the ability of the plasma-ascitic albumin gradient to diagnose portal hypertension. This communication presents an explanation of ascites based solely on pathophysiological alterations within the peritoneal cavity. A quantitative model is described based on experimental vascular and intraperitoneal pressures, lymph flow, and peritoneal space compliance. The model's predictions accurately mimic clinical observations in ascites, including the magnitude and time course of changes observed following paracentesis or diuretic therapy

    Wellbeing indicators affecting female entrepreneurship in OECD countries

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    [EN] The objective of this research is to know which wellbeing indicators, such as work-life balance, educational level, income or job security, are related to the rate of female entrepreneurship in 29 OECD countries. In addition, these countries have been classified according to the motivation of the entrepreneur either by necessity or by opportunity. The empiric study is focused on 29 OECD countries covering the different geographic areas (Western Europe, Central and Eastern Europe, Middle East, etc.) Due to the fact that the sample is relatively small, it is essential to use a selective approach when selecting the causal conditions. To this end, fsQCA is the most appropriate methodology for such a small data set. A total of 5 variables have been used: an independent variable (female TEA ratio), and four dependent variables (work life balance, educational level, sustainable household income and job security). Data measuring female TEA ratio have been obtained from Global Entrepreneur Monitor (GEM in Global report, 2015) data base, while data measuring wellbeing dimensions were taken from the Better Life Index (OECD in How¿s life? Measuring wellbeing, 2015. http://www.oecdbetterlifeindex.org). The results of this piece of research show that countries with high sustainable household income together with high level of education achieves high female entrepreneurship ratio with both, a good work-life balance (despite of a high unemployment probability), or a high labour-personal imbalance (in this latter, with a low probability of unemployment).This work has been funded by the R + D project for emerging research groups with reference (GVA) GV/2016/078.Ribes-Giner, G.; Moya Clemente, I.; Cervelló Royo, RE.; Perelló Marín, MR. (2019). Wellbeing indicators affecting female entrepreneurship in OECD countries. 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Springer, Cham (2015)Cervelló-Royo, R., Guijarro, F., Martinez-Gomez, V.: Social performance considered within the global performance of Microfinance Institutions: a new approach. Oper. Res. (2017). https://doi.org/10.1007/s12351-017-0360-3Chaaban, J., Irani, A., Khoury, A.: The composite global wellbeing index (CGWBI): a new multi-dimensional measure of human development. Soc. Indic. Res. 129(1), 465–487 (2016). https://doi.org/10.1007/s11205-015-1112-5Chapple, S.: Child wellbeing and sole-parent family structure in the OECD: an analysis. OECD. Social, employment, and migration working papers (82), 0_1 (2009)Christofides, L.N., Polycarpou, A., Vrachimis, K.: Gender wage gaps, “sticky floors” and “glass ceilings” in Europe. Labour Econ. 21, 86–102 (2013). https://doi.org/10.1016/j.labeco.2013.01.003Cumming, D., Hou, W., Lee, E.: Sustainable and ethical entrepreneurship, corporate finance and governance, and institutional reform in China. J. Bus. 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Change 43(3), 719–750 (2012). https://doi.org/10.1111/j.1467-7660.2012.01780.xGEM (Global Entrepreneurship Monitor): Global report (2015)Harter, J.K., Schmidt, F.L., Keyes, C.L.M.: Wellbeing in the workplace and its relationship to business outcomes. A review of the Gallup studies. In: Keyes, C.L.M., Haidt, J. (eds.) Flourishing: The Positive Person and the Good Life, pp. 205–224. American Psychologi cal Association, Washington (2003)Henry, C., Foss, L., Ahl, H.: Gender and entrepreneurship research: a review of methodological approaches. Int. Small Bus. J. 34(3), 217–241 (2015). https://doi.org/10.1177/0266242614549779Hessels, J., Van Gelderen, M., Thurik, R.: Entrepreneurial aspirations, motivations, and their drivers”. Small Bus. Econ. 31(3), 323–339 (2008). https://doi.org/10.1007/s11187-008-9134-xIezzi, D.F., Deriu, F.: Women active citizenship and wellbeing: the Italian case. Qual. Quant. 48(2), 845–862 (2014)Jansson, T.: Housing choices and labor income risk. J. Urban Econ. 99, 107–119 (2017). https://doi.org/10.1016/j.jue.2016.12.006Johansen, V., Foss, L.: The effects of entrepreneurship education—does gender matter? Int. J. Entrep. Small Bus. 20(3), 255–271 (2013). https://doi.org/10.1504/IJESB.2013.056889Judge, W.Q., Hu, H.W., Gabrielsson, J., Talaulicar, T., Witt, M.A., Zattoni, A., Kibler, B.: Configurations of capacity for change in entrepreneurial threshold firms: imprinting and strategic choice perspectives. J. Manag. Stud. 52(4), 506–530 (2015). https://doi.org/10.1111/joms.12121Kautonen, T., Kibler, E., Minniti, M.: Late-career entrepreneurship, income and quality of life. J. Bus. Ventur. 32(3), 318–333 (2017). https://doi.org/10.1016/j.jbusvent.2017.02.005Kephart, P., Schumacher, L.: Has the “glass ceiling” cracked? An exploration of women entrepreneurship. J. Leadersh. Organ. Stud. 12(1), 2–15 (2005). https://doi.org/10.1177/107179190501200102Kirkwood, J.: Motivational factors in a push–pull theory of entrepreneurship. Gend. 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Theory Pract. 31(3), 341–364 (2007). https://doi.org/10.1111/j.1540-6520.2007.00177.xLee, S.S.Y.: Examining policy configurations as conditions for long-term unemployment and non-standard employment in OECD countries using fuzzy-set analysis. Qual. Quant. 47(6), 3521–3536 (2013)Leffler, E., Svedberg, G.: Enterprise learning: a challenge to education? Eur. Educ. Res. J. 4(3), 219–227 (2005)Levie, J., Autio, E.: A theoretical grounding and test of the GEM model. Small Bus. Econ. 31(3), 235–263 (2008). https://doi.org/10.1007/s11187-008-9136-8Maccagnan, A., Wren-Lewis, S., Brown, H., Taylor, T.: Wellbeing and society: towards quantification of the co-benefits of wellbeing. Soc. Indic. Res. 1–27 (2018)Mandl, C., Berger, E.S.C., Kuckertz, A.: Do you plead guilty? Exploring entrepreneurs’ sensemaking-behavior link after business failure. J. Bus. Ventur. 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    Hedonic and incentive signals for body weight control

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    Here we review the emerging neurobiological understanding of the role of the brain’s reward system in the regulation of body weight in health and in disease. Common obesity is characterized by the over-consumption of palatable/rewarding foods, reflecting an imbalance in the relative importance of hedonic versus homeostatic signals. The popular ‘incentive salience theory’ of food reward recognises not only a hedonic/pleasure component (‘liking’) but also an incentive motivation component (‘wanting’ or ‘reward-seeking’). Central to the neurobiology of the reward mechanism is the mesoaccumbal dopamine system that confers incentive motivation not only for natural rewards such as food but also by artificial rewards (eg. addictive drugs). Indeed, this mesoaccumbal dopamine system receives and integrates information about the incentive (rewarding) value of foods with information about metabolic status. Problematic over-eating likely reflects a changing balance in the control exerted by hypothalamic versus reward circuits and/or it could reflect an allostatic shift in the hedonic set point for food reward. Certainly, for obesity to prevail, metabolic satiety signals such as leptin and insulin fail to regain control of appetitive brain networks, including those involved in food reward. On the other hand, metabolic control could reflect increased signalling by the stomach-derived orexigenic hormone, ghrelin. We have shown that ghrelin activates the mesoaccumbal dopamine system and that central ghrelin signalling is required for reward from both chemical drugs (eg alcohol) and also from palatable food. Future therapies for problematic over-eating and obesity may include drugs that interfere with incentive motivation, such as ghrelin antagonists

    Milk: an epigenetic amplifier of FTO-mediated transcription? Implications for Western diseases

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    Variation in virulence of Septoria tritici Rob ex Desm isolates on wheat

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    To identify physiologic races, the variation in virulence of 10 local Septoria tritici Rob ex Desm isolates was evaluated on 10 wheat differentials selected in Israel and 7 previously tested Argentine cultivars (cvs). Pycnidial leaf coverage percentage (PC) and necrotic lesion percentage (NL) were used to determine cvs reaction in order to compare their efficiency in isolate differentiation. Isolates behaved differently on the different wheat cvs. The 2 variables showed which isolates behaved similarly, and which behaved differently; PC was more sensitive in detecting these differences. The ranking of varieties for PC and NL was different for every isolate x cv combination, and few ordering patterns coincided (Bobwhite "S", lassul 20 and Bordenave Puán). In general, local isolates induced more PC than NL on national cvs. Two isolates (I11, I19) behaved in the most virulent manner; 2 others (I21, I25) provoked the highest resistant reaction percentage on the cvs tested. Isolate x cv interaction varied according to the parameter evaluated. The analysis of variance for PC indicated significant interaction between the 2 main factors (P = 0.01) which may be considered as an index of pathogen physiologic specialization. However, a non-significant interaction (P = 0.01) for NL indicated only differences between isolates degree of aggressiveness. Low degree of specificity of the interactions and similar order in the ranking of disease severity on some cvs showed no "true physiologic races". The international set did not supply any major variation range in lesion type and percentage or more consistent cv reactions in differentiating biotypes. Thus, the standardization of research methodologies is necessary to study S tritici-Triticum sp interactions. This would contribute to the reproducibility of results obtained by different authors throughout the world and thus avoid different interpretations of varietal reaction.Variation de la virulence d'isolats de Septoria tritici Rob ex Desm sur blé. La variation de virulence de 10 isolats de Septoria tritici a été évaluée sur 17 variétés de blé sélectionnées : 10 en Israël et en Argentine, pour identifier des races physiologiques (tableau I). La réaction des variétés est déterminée afin d'estimer l'effet de la méthode d'évaluation de la différenciation des souches et montrer les différences de comportement des variétés de blé par l'emploi de 2 variables : - le pourcentage de lésions nécrotiques avec pycnides (NL), - le pourcentage de couverture de la surface foliaire totale par des pycnides (PC). Les 2 variables, PC et PN, permettent de séparer les isolats en fonction de leur comportement, mais avec un net avantage pour PC. La magnitude de la surface nécrosée et la couverture pycnidiale donnent des résultats différents pour chaque combinaison : souche/variété (tableau III). II existe peu de concordance entre les classements (variétés Bobwhite "S", lassul 20 et Bordenave Puán). Les isolats locaux ont, en général, révélé plus de PC que de NL dans les variétés nationales (tableaux IV et V). Deux d'entre eux (I11 et I19) se sont montrés plus virulents alors que 2 autres (I 21 et I25) ont le pourcentage le plus élevé de réactions de résistance sur les 17 variétés testées. L'interaction souche/variété varie selon le paramètre d'évaluation considéré : une valeur significative (P = 0,01) pour PC peut être considérée comme un indice de spécialisation physiologique de l'agent pathogène mais, une interaction non significative (P = 0,01) pour NL n'a montré que des différences dans le degré d'agressivité des isolats. En outre, le faible degré de spécificité des interactions, et l'ordre similaire de l'évaluation de la gravité de la maladie sur certaines variétés montrent qu'ils n'ont pas mis en évidence de «vraies races physiologiques». L'emploi de la gamme internationale d'hôtes différentiels n'a pas fourni plus de variation pour le type et le pourcentage de lésion, ni de réactions des variétés, plus solides et plus claires, dans le but de différencier des biotypes. Enfin, il faut insister sur le besoin de standardiser les conditions d'inoculation et d'évaluation des études d'interactions S tritici/Triticum sp, afin d'assurer la reproductibilité des résultats au niveau mondial et d'éviter les différences d'interprétation de réaction des variétés qui surgissent par l'emploi de méthodologies variables

    Impact of transient correction of increased adrenocortical activity in hypothalamo-damaged, hyperadipose female rats.

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    OBJECTIVE: To explore the effects of transient correction of enhanced corticoadrenal activity in monosodium L-glutamate (MSG)-damaged female rats on peripheral insulin sensitivity and in vitro retroperitoneal (RP) adipocyte function. DESIGNS: A dose of 4 mg/g body weight (BW) of MSG or vehicle (CTR) was i.p. injected, once every 2 days, between days 2 and 10 of age, in female rats. Intact and 21 day-operated (sham or adrenal enucleation (AE)) rats from both (CTR and MSG) groups were used for experimentation on day 120 of age. Circulating levels of several hormones, in basal and after i.v. high-glucose load conditions, and RP adiposity morphology and function were then evaluated. RESULTS: MSG rats developed increased adrenocortical function, hyperadiposity, hyperleptinemia, hyperinsulinemia and decreased peripheral insulin sensitivity. These characteristics were fully reversed after transient correction of corticoadrenal hyperactivity induced by AE. In addition, in vitro experimentation with isolated RP adipocytes indicated that cells from intact MSG animals displayed decreased sensitivity to insulin and dexamethasone stimulation of leptin secretion. Interestingly, adipocyte dysfunction in MSG rats was fully abrogated after AE-induced transient correction of insulinemia, leptinemia and adrenocortical activity. Importantly, the reversion of these metabolic abnormalities, induced by AE for 21 days, in MSG animals did occur, despite no significant changes in BW values. CONCLUSION: Our results support that the changes in adipocyte characteristics and peripheral insulin resistance, developed in this pseudo-obese female rat model, are mainly due to increased glucocorticoid production. Importantly, appropriate correction of the enhanced adrenocortical activity fully reversed these abnormal functions

    Label-free measuring and mapping of binding kinetics of membrane proteins in single living cells

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    Membrane proteins (MPs) mediate a variety of cellular responses to extracellular signals. While MPs are intensely studied for their values as disease biomarkers and therapeutic targets, in situ investigation of binding kinetics of MPs with their ligands has been a challenge. Traditional approaches isolate MPs and then study them ex situ, which does not accurately reflect their native structures and functions. We present here a label-free plasmonic microscopy method to map the local binding kinetics of MPs in their native environment. This new analytical method can perform simultaneous plasmonic and fluorescence imaging, thus making it possible to combine the strengths of both label-based and label-free techniques in one system. Using this method, we have determined the distribution of MPs on the surface of single cells, and the local binding kinetic constants of different MPs. Furthermore, we have studied the polarization of the MPs on the cell surface during chemotaxis
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