Drug delivery to tumours using a novel 5-FU derivative encapsulated into lipid nanocapsules

In this work, a novel lipophilic 5-fluorouracil (5-FU) derivative was synthesised and encapsulated into lipid nanocapsules (LNC). 5-FU was modified with lauric acid to give a lipophilic mono-lauroyl-derivative (5-FU-C12, MW of about 342 g/mol, yield of reaction 70%). 5-FU-C12 obtained was efficiently encapsulated into LNC (encapsulation efficiency above 90%) without altering the physico-chemical characteristics of LNC. The encapsulation of 5-FU-C12 led to an increased stability of the drug when in contact with plasma being the drug detectable until 3 h following incubation. Cytotoxicity assay carried out using MTS on 2D cell culture showed that 5-FU-C12-loaded LNC had an enhanced cytotoxic effect on glioma (9L) and human colorectal (HTC-116) cancer cell line in comparison with 5-FU or 5-FU-C12. Then, HCT-116 tumour spheroids were cultivated and the reduction of spheroid volume was measured following treatment with drug-loaded LNC and drugs alone. Similar reduction on spheroids volume was observed following the treatment with drug-loaded LNC, 5-FU-C12 and 5-FU alone, while blank LNC displayed a reduction in cell viability only at high concentration. Globally, our data suggest that the encapsulation increased the activity of the 5-FU-C12. However, in-depth evaluations of LNC permeability into spheroids are needed to disclose the potential of these nanosystems for cancer treatment

Prévision de la demande en eau pour l'irrigation

In the context of economic pre-feasibility study for the design of an irrigation system, Cemagref has developed a methodology and implemented it in the Plaine du Forez region (Loire-Center of France). Its main claim is to evaluate the medium term agricultural water demand in order to fit water requirements to water resources. The methodology is based on the analysis of farm management, focusing on an agricultural supply model using linear programming. Simulations are implemented with different scenarios of changes in the economic and irrigation context. The methodology can be considered as a decision support tool for the technical ans financial design of irrigation systems. Its use should be restricted to pre-feasibility on small areas (around 200 farms). / Dans le cadre des études préalables à un projet d'irrigation, l'objectif de la méthodologie présentée est d'assurer une bonne adéquation, à court et moyen terme, entre les besoins en eau de l'ensemble des usages et les ressources en eau mobilisées. La démarche repose sur l'analyse du système de production agricole et la construction d'un modèle d'offre agrégé à l'échelle du périmètre irrigué, à partir d'une modélisation du comportement des différents types d'exploitants agricoles. Sa spécificité réside dans la prise en compte de la diversité de comportement des exploitants agricoles face à l'irrigation et dans la localisation des résultats. Les principaux résultats concernent l'évaluation et la localisation de la demande en eau agricole à court et moyen terme. Ils constituent des éléments d'aide à la décision particulièrement destinés aux acteurs concernés par l'aménagement (Etat, collectivités locales, gestionnaires, agriculteurs,...

Plasticity of skeletal myosin in endurance trained rats, a qualitative study

Dissertação de mestrado em Ecologia, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de CoimbraAs emissões de mercúrio aumentaram nas últimas décadas, afetando áreas remotas, como a Antártida. A localização das colónias de pinguim-gentoo (Pygoscelis papua) na região da Antártida faz desta espécie um bom bio-monitor das concentrações de mercúrio nesta região. Este trabalho avalia as concentrações de mercúrio nas penas de pinguim-gentoo em Bird Island, Geórgia do Sul nos anos de 2009 e 2010. A localização desta ilha mais próximo da ação humana pode significar um maior nível de contaminação, numa das maiores colónias desta espécie. Além disso, o conhecimento prévio das interações tróficas neste local permite a compreensão da transferência de mercúrio ao longo da cadeia trófica. Não houve diferenças significativas nos níveis de mercúrio entre 2009 e 2010 (0.97±0.67 mg kg-1; 1.13±0.62 mg kg-1, respetivamente). Verificou-se um aumento dos níveis de mercúrio com o aumento do peso e da proporção de peixe na dieta dos pinguins. No entanto, o género não teve influência nestes níveis. Os coeficientes de variação foram altos em 25% da população, a qual apresentou diferenças significativas entre os valores máximos e mínimos de concentração de mercúrio nas penas. Esta variação pode ser causada por diferenças nos padrões de muda entre indivíduos da mesma população, o que pode levar a diferentes interpretações quando toda a população é analisada. Não foram verificadas variações temporais nos níveis de mercúrio nas penas destes pinguins, mas, em comparação com estudos anteriores, as diferenças espaciais na região Antártida são evidentes. Estes resultados demonstram que os animais de nível trófico superior, cuja alimentação se baseie nesta espécie, estão sujeitos a potenciais efeitos no seu desenvolvimento e reprodução.Mercury emissions have increased over the last decades and are affecting even remote areas such as Antarctica. As Gentoo penguins (Pygoscelis papua) breed around Antarctica and forage nearby their colonies, they may characterize the mercury concentrations in the region. We evaluated here the mercury concentrations in Gentoo penguin feathers at Bird Island, South Georgia at 2009 and 2010. Its location close to anthropogenic sources may indicate a higher level of contamination in one of the largest colonies of this species. Besides, trophic interactions here are well-studied, allowing the understanding of mercury transference through food-webs. There were no significant differences in mercury levels between 2009 and 2010 (0.97±0.67 mg kg-1; 1.13±0.62 mg kg-1, respectively). There was an increase of mercury levels with increasing weight and proportion of fish on penguins’ diet, but sex had no influence on it. The coefficients of variation were high in 25% of the population which presented significant differences between the minimum and maximum value of mercury concentrations in the feathers. This may be caused by differences in moult patterns within the population leading to different interpretations if included in the overall population. No temporal variations in levels of mercury in Gentoo penguin feathers were observed, but spatial differences are clear in the Antarctic region when comparing with previous studies elsewhere around Antarctica. These results highlight possible implications for other animals up in the food web that feed considerably on gentoo penguins, namely on reproduction and developmen

An Application of ARDL Approach

The paper examines the relationship between financial development and income inequality; and also explores if the Greenwood and Jovianvich (GJ) hypothesis applies to Pakistan. Using data from 1971 to 2005, the paper implements the Auto Regressive Distributed Lag (ARDL) bounds testing approach to cointegration to examine the existence of long run; and the error correction model (ECM) for the short run relationships. Stationarity properties of the series are checked by the ADF method. The findings indicate that financial development reduces income inequality while financial instability aggravates it. Contrary to the conventional wisdom, we find economic growth worsens income distribution and that the latter is deteriorated further by trade openness. The paper does not find support for the GJ relation. Appropriate reforms aimed at developing a well-organized financial sector in Pakistan can help reduce income inequality

Henri Tardieu (1946-2010)

National audienceHenri Tardieu nous a quittés le 2 avril 2010. Passionné par l'eau et l'environnement, il était devenu Ingénieur du génie rural, des eaux et des forêts après avoir été l'un des plus jeunes diplômés de l'École polytechnique

Melting of 1-Alcohol Mololayers at the Air-Water Interface. I. X-Ray Reflectivity Investigations

The melting of 1-alcohol monolayers adsorbed at the air-water interface has been studied using X-ray reflectivity. This technique allows for an accurate determination of the thickness and the density of the monolayer. The reflectivity, both in specular and non-specular directions, over a large temperature range of different chain lengths (from C$_{10}$ to C$_{16}$) have been interpreted using a model taking into account the scattering from thermally induced capillary-wave fluctuations and the instrumental resolution. The density and the thickness of the aliphatic layer exhibit a clear discontinuity at the solid-liquid transition. Large changes with temperature in the packing of the monolayer are observed in both the solid and the liquid phase. In the crystal phase, the fitted thicknesses are lower than all-trans molecular chain lengths. In the liquid phase, the density remains 10% larger than in bulk liquid phases.La fusion de monocouches de 1-alcool adsorbées à l'interface air-eau est étudiée par réflectivité des rayons X. Cette technique permet une détermination précise de l'épaisseur et de la densité de la monocouche. Les mesures de réflectivité effectuées dans chacune des directions spéculaire et non spéculaire, ont été interprétées à l'aide d'un modèle tenant compte de la résolution expérimentale et de la diffusion par les fluctuations capillaires thermiques. La densité et l'épaisseur de la couche aliphatique présentent une claire discontinuité à la transition solide-liquide. D'importants changements de la compacité de la monocouche sont observés dans chacune des phases solide et liquide sous l'effet de la température. Dans la phase cristalline, les épaisseurs de la monocouche obtenues sont plus petites que celles de molécules dans une conformation “trans-trans”. Dans la phase liquide, la valeur de la densité reste 10% plus élevée que celle de la phase liquide volumique 3D

Electrochemical removal of nox on pt-ba impregnated lscf/gdc electrode

SSCI-VIDE+CARE+AWS:PVEInternational audienceNon

Electrochemical removal of nox on pt-ba impregnated lscf/gdc electrode

SSCI-VIDE+CARE+AWS:PVEInternational audienceNon