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International audience; The paper examines how space is usually included into models dedicated to simulate interactions between anthroposystems and environment. The role of space in modelling depends on the aim of the model. Today, most of the simulation models are focused on understanding the behaviour of complex socioeconomic and biophysical systems, with multiple interlinked components. These models are intended for specialists and quite difficult to use. At the same time, spatial models are needed to provide municipalities with a tool that they can use easily to manage their territory and to assist decision-makers in local planning. These models are relevant to geoprospective purposes. An example of spatio-morphological modelling used to predict urban sprawl is presented.; Ce texte examine la manière dont l'espace est habituellement intégré à la modélisation des interactions nature-société. Le rôle accordé à l'espace dépend de la finalité du modèle. Aujourd'hui, la plupart des modèles sont dédiés à la compréhension du fonctionnement d'anthroposystèmes et d'écosystèmes complexes, aux multiples composantes interreliées et restent du ressort de spécialistes. Parallèlement, il existe, dans le domaine de l'aménagement local, une forte demande en modélisation spatiale, accessible à des non spécialistes, et qui permette d'assister les décideurs dans leurs orientations d'aménagement. Ces modèles relèvent de la géoprospective territoriale. Un exemple de modélisation spatio-morphologique appliquée à la prévision de l'étalement urbain est présenté.

Cet article relève tout d’abord quelques faiblesses et dysfonctionnements dans les actions menées en faveur du développement durable et en analyse les causes. L’une des raisons majeures tient au fait que la durabilité urbaine est encore trop souvent traitée de manière sectorielle sans se soucier des interdépendances spatiales des systèmes urbains et des systèmes territoriaux avoisinants. La deuxième partie analyse la durabilité sous l’angle opérationnel. Elle propose des méthodes, de modélisation notamment, qui permettent de comprendre le fonctionnement d’un système urbain durable.First this paper presents some weakness and dysfunction in taking action for urban sustainability and gives the reasons. The fact that urban sustainability researchs do not take into account the systemic links between urban spaces and surrounding spaces, is one of the most important reasons. In the second stage the urban sustainability is analysed with an operational point of view. We present modelling methods which allow to understand how sustainable urban systems work and how to plan the city of the future according to sustainability.

Prenent com a exemple la síntesi química de l'amoníac, es defensa la contribució positiva de la ciència química en la millora de la salut de la humanitat a través de l'alimentació, més enllà dels perills de la contaminació ambiental, que generalment es veu magnificada pels mitjans de comunicació amb poc fonament científic. També es descriu en profunditat el cas recent de la presència de dioxines en els salmons de viver del nord d'Europa, se n'analitzen les causes i s'aporten dades quantitatives per a la interpretació dels avantatges i riscos que comporta el seu consum, la qual cosa demostra la complexitat de les interrelacions entre química, aliments i salut.

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Nuclear factor kappaB (NF-kappaB)-inducing kinase (NIK), IkappaB kinase (IKK)-alpha and -beta, and IkappaBalpha are common elements that signal NF-kappaB activation in response to diverse stimuli. In this study, we analyzed the role of this pathway during insulin-like growth factor II (IGF-II)-induced myoblast differentiation. L6E9 myoblasts differentiated with IGF-II showed an induction of NF-kappaB DNA-binding activity that correlated in time with the activation of IKKalpha, IKKbeta, and NIK. Moreover, the activation of IKKalpha, IKKbeta, and NIK by IGF-II was dependent on phosphatidylinositol 3-kinase, a key regulator of myogenesis. Adenoviral transduction with the IkappaBalpha(S32A/S36A) mutant severely impaired both IGF-II-dependent NF-kappaB activation and myoblast differentiation, indicating that phosphorylation of IkappaBalpha at Ser-32 and Ser-36 is an essential myogenic step. Adenoviral transfer of wild-type or kinase-deficient forms of IKKalpha or IKKbeta revealed that IKKalpha is required for IGF-II-dependent myoblast differentiation, whereas IKKbeta is not essential for this process. Finally, overexpression of kinase-proficient wild-type NIK showed that the activation of NIK is sufficient to generate signals that trigger myogenin expression and multinucleated myotube formation in the absence of IGF-II.

GLUT1 glucose transporters are highly expressed in proliferating and transformed cells as well as in tissues during fetal life. However, the mechanisms that regulate GLUT1 gene expression remain largely unknown. Here, we demonstrate that Sp3 proteins bind to the GLUT1 proximal promoter gene and inhibit transcriptional activity in muscle and non-muscle cells. Two different Sp3 translational products (110 and 74 kDa) derived from differential translational initiation were detected in nuclear extracts from myoblast cells, and both Sp3 protein species inhibited GLUT1 gene transcriptional activity. The inhibitory effect of Sp3 was dominant over the stimulatory effect of Sp1 on transcriptional activity of GLUT1 gene. Furthermore, abolition of Sp3 binding to the proximal promoter of GLUT1 gene completely blocked the response to Sp3. We provide evidence that the expression of Sp3 protein is subject to regulation in muscle cells and that this is likely to control GLUT1. Thus, Sp3 protein was up-regulated in the absence of changes in Sp1 early after the induction of IGF-II-dependent myogenesis. Furthermore, forced over-expression of MyoD caused an enhancement in the cellular Sp3/Sp1 ratio which was concomitant to a reduced GLUT1 expression. Later during myogenesis, Sp3 expression was substantial whereas Sp1 was markedly down-regulated. In summary, we provide direct evidence that the transcription factor Sp3 represses gene expression in non-muscle and muscle cells and this is likely to operate in fetal heart by binding to the GLUT1 gene promoter. This is the first description of a repressor of GLUT1 gene transcription. Furthermore, we propose that variations in the ratio of Sp3 versus Sp1 regulate GLUT1 promoter activity and this is crucial in the down-regulation of GLUT1 associated to myogenesis.

Insulin-like growth factors (IGFs) are potent inducers of skeletal muscle differentiation and phosphatidylinositol (PI) 3-kinase activity is essential for this process. Here we show that IGF-II induces nuclear factor-kappaB (NF-kappaB) and nitric-oxide synthase (NOS) activities downstream from PI 3-kinase and that these events are critical for myogenesis. Differentiation of rat L6E9 myoblasts with IGF-II transiently induced NF-kappaB DNA binding activity, inducible nitric-oxide synthase (iNOS) expression, and nitric oxide (NO) production. IGF-II-induced iNOS expression and NO production were blocked by NF-kappaB inhibition. Both NF-kappaB and NOS activities were essential for IGF-II-induced terminal differentiation (myotube formation and expression of skeletal muscle proteins: myosin heavy chain, GLUT 4, and caveolin 3), which was totally blocked by NF-kappaB or NOS inhibitors in rat and human myoblasts. Moreover, the NOS substrate L-Arg induced myogenesis in the absence of IGFs in both rat and human myoblasts, and this effect was blocked by NOS inhibition. Regarding the mechanisms involved in IGF-II activation of NF-kappaB, PI 3-kinase inhibition prevented NF-kappaB activation, iNOS expression, and NO production. Moreover, IGF-II induced, through a PI 3-kinase-dependent pathway, a decrease in IkappaB-alpha protein content that correlated with a decrease in the amount of IkappaB-alpha associated with p65 NF-kappaB.

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L’echelle DEGR est le seul outil francophone actuellement valide pour evaluer la douleur prolongee chez l’enfant de 2 a 6 ans. Neanmoins, sa complexite limite son utilisation au quotidien. Forts de ce constat, nous proposons une echelle simplifiee elaboree selon une methodologie de simplification des echelles composites et presentons l’etude de validation de cette echelle. Methode L’echelle HEDEN a ete elaboree par consensus d’experts, en choisissant parmi les items de DEGR 2 items traduisant les signes directs de douleurs (SDD) (position antalgique et controle exerce par l’enfant quand on le mobilise), 2 items traduisant l’atonie psychomotrice (APM) (interet pour le monde exterieur et lenteur et rarete des mouvements) et 1 item d’expression volontaire de douleur (EVD) (plaintes somatiques). L’etude de validation comporte une evaluation de la faisabilite, une etude de validite afin de montrer une correlation avec une echelle validee (DEGR), une etude de concordance interobservateur et une etude de fiabilite afin d’estimer la variabilite due a la mesure (coef α de Cronbach). Resultats l’etude de faisabilite (59 enfants) montre une correlation admissible entre HEDEN et DEGR (r = 0,5). La fiabilite de l’echelle HEDEN est bonne (α= 0,61) ainsi que la concordance inter observateur (r = 0,62). Dans l’etude de validation (48 enfants), l’analyse en composantes principales confirme les 3 domaines de representation des phenomenes douloureux que sont les SDD, l’APM et l’EVD. Les correlations entre les scores des 5 items HEDEN et le score DEGR sont toutes significatives entre 0,31 et 0,64. La correlation entre les scores globaux DEGR et HEDEN est bonne (=0,60, p La duree moyenne de remplissage de la grille HEDEN est de 4,42 mn (1 a 32) versus 23,09 mn (5 a 50) pour la grille DEGR. Conclusion HEDEN permet de quantifier de maniere rapide et objective la douleur prolongee de l’enfant. Elle semble adaptee a une pratique quotidienne au lit du malade par l’ensemble des soignants et son apprentissage est aise.

Insulin-like growth factors (IGFs) are potent stimulators of muscle differentiation, and phosphatidylinositol 3-kinase (PI 3-kinase) is an essential second messenger in this process. Little is known about the downstream effectors of the IGF/PI 3-kinase myogenic cascade, and contradictory observations have been reported concerning the involvement of p70 S6 kinase. In an attempt to clarify the role of p70 S6 kinase in myogenesis, here we have studied the effect of rapamycin on rat, mouse, and human skeletal muscle cell differentiation. Both insulin and IGF-II activated p70 S6 kinase in rat L6E9 and mouse Sol8 myoblasts, which was markedly inhibited at 1 ng/ml rapamycin concentrations. Consistent with previous observations in a variety of cell lines, rapamycin exerted a potent inhibitory effect on L6E9 and Sol8 serum-induced myoblast proliferation. In contrast, even at high concentrations (20 ng/ml), rapamycin had no effect on IGF-II-induced proliferation or differentiation. Indeed, neither the morphological differentiation, as assessed by myotube formation, nor the expression of muscle-specific markers such as myogenin, myosin heavy chain, or GLUT4 (glucose transporter-4) glucose carriers was altered by rapamycin. Moreover, here we extended our studies on IGF-II-induced myogenesis to human myoblasts derived from skeletal muscle biopsies. We show that, as observed for rat and mouse muscle cells, human myoblasts can be induced to form multinucleated myotubes in the presence of exogenous IGF-II. Moreover, IGF-II-induced human myotube formation was totally blocked by LY294002, a specific PI 3-kinase inhibitor, but remained unaffected in the presence of rapamycin.

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Um isolado do fungo entomógeno Nomuraea rileyi (Farlow) Samson, oriundo de Londrina (PR), foi estudado com referência a alguns aspectos de sua nutrição e de seu comportamento na presença de 16 fungicidas, 16 inseticidas e 8 herbicidas indicados para a cultura da soja. Foram levados em consideração fatores como regime luminoso dosagem de extrato de levedura, concentração do inóculo e dias de incubação na esporulação do fungo. Também tentou-se verificar a deficiência nutricional de N. rileyi. Os defensivos agrícolas foram testados "in vitro" em três concentrações (10, 100 e 1000 ppm) e os cálculos destas dosagens foram feitos considerando-se apenas o ingrediente ativo presente no produto comercial. Além dos aspectos nutricionais estudados, observou-se que o hábito de crescimento de N. rileyi não se apresenta, inicialmente, com aspecto leveduriforme quando é cultivado sobre meio mínimo enriquecido com extrato de levedura. Foi verificado que a presença de luz e a quantidade de extrato de levedura influenciam positivamente a esporulação do fungo. As duas concentrações de inóculo usadas (104 e 106 esporos/ml) não tiveram efeito sobre a quantidade de esporos produzidos pelo fungo. Observou-se também que a caseína mais vitaminas pode substituir parcialmente o extrato de levedura, porém, o crescimento e a esporulação do fungo são retardadas. Os fungicidas, de maneira geral, inibiram tanto o crescimento como a esporulação do fungo, entretanto, o Dodine e o Chloroneb mostraram-se completamente inócuos nas três concentrações usadas. Dos 16 inseticidas testados, o CGA 15. 324, Lindane, Parathion e Fenitrothion inibiram o desenvolvimento micelial e esporulação de N. rileyi e Phosalone, Toxafeno + Phosalone, Endossulfan e Camphechlor inibiram apenas a esporulação do fungo. De 8 herbicidas testados sobre o fungo, apenas o inibiu o desenvolvimento do micélio e a esporulação do fungo. Pode ser concluído, através do estudo com defensivos, que o Dinoseb processo de esporulação de N. rileyi é mais sensível aos produtos químicos testados do que o desenvolvimento micelial. Anisolate of the entomogenous fungus Nomuraea rileyi (Farlow) Samson from Londrina - State of Paraná (Brasil) was studied with reference to some of its nutritional and behavioural aspects in the presence of forty pesticides used today and those that could be used in soybeans, in future. The effects on the fungus sporulation by the presence or absence of light, amount of yeast extract, inoculum concentration and periods of incubation were studied. Also the effects of some agricultural pesticides at three concentrations, (10, 100 and 1000 ppm), of the active ingredient, were tested for their effect on this fungus. It was found that N. rileyi does not show the cultural appearence of bacteria or yeasts as described by KISH et alii (1974), when grown on a minimum medium enriched with yeast extract. The presence of light and the amount of yeast extract positively influenced the process of sporulation of the fungus. Two concentrations of inoculum (104 and 106 spores/ml) showed no difference in sporulation of the fungus. The amount of yeast extract in the medium was found to enhance the process of sporulation of N. rileyi the microrganism sporulated more slowly in the presence of casein hydrolisate plus vitamins in the minimum medium than it did in the presence of yeast extract. The fungicides generally inhibited growth and sporulation of the fungus, except Dodine and Chloroneb which had no visible effect in all the tests. Of the fourteen insecticides tested, only CGA 15.324, Lindane, Parathion and Fenitrothion inhibited the mycelial growth and sporulation, whereas Toxafeno + Phosalone, Phosalone, Endossulfan and Camphechlor inhibited only sporulation. Of the eight herbicides tested, seven did not inhibit the fungus; only Dinoseb reduced both the amounts of mycelia and sporulation. It can be concluded that the sporulation process of N. rileyi more sensitive to pesticides than its mycelial growth is.