166 resultados para Major Event

em Université de Lausanne, Switzerland


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(résumé de l'ouvrage) Studies on Origen at the beginning of the 21st century continue to dig old and new grounds of research. After the epoch-making rediscovery of the great Alexandrian doctor throughout the past century, contemporary research increasingly deals with the close context of his writings and thought: the cultural tradition of Alexandria in all its components - Hellenistic, Jewish, Egyptian, Gnostic and Christian. This topic was the theme chosen for the «Colloquium Origenianum Octavum» (Pisa, 27-31 August 2001), a major event of patristic scholarship. The proceedings now contain more than 100 papers of contributors from about 30 countries. They not only provide the best overview on a lively field of studies but also demonstrate how Origen's heritage in Christian history and theology carried with it the imprint of one of the most vital traditions of Western civilization.

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The therapeutic activity of selective serotonin (5-HT) reuptake inhibitors (SSRIs) relies on long-term adaptation at pre- and post-synaptic levels. The sustained administration of SSRIs increases the serotonergic neurotransmission in response to a functional desensitization of the inhibitory 5-HT1A autoreceptor in the dorsal raphe. At nerve terminal such as the hippocampus, the enhancement of 5-HT availability increases brain-derived neurotrophic factor (BDNF) synthesis and signaling, a major event in the stimulation of adult neurogenesis. In physiological conditions, BDNF would be expressed at functionally relevant levels in neurons. However, the recent observation that SSRIs upregulate BDNF mRNA in primary cultures of astrocytes strongly suggest that the therapeutic activity of antidepressant drugs might result from an increase in BDNF synthesis in this cell type. In this study, by overexpressing BDNF in astrocytes, we balanced the ratio between astrocytic and neuronal BDNF raising the possibility that such manipulation could positively reverberate on anxiolytic-/antidepressant-like activities in transfected mice. Our results indicate that BDNF overexpression in hippocampal astrocytes produced anxiolytic-/antidepressant-like activity in the novelty suppressed feeding in relation with the stimulation of hippocampal neurogenesis whereas it did not potentiate the effects of the SSRI fluoxetine on these parameters. Moreover, overexpressing BDNF revealed the anxiolytic-like activity of fluoxetine in the elevated plus maze while attenuating 5-HT neurotransmission in response to a blunted downregulation of the 5-HT1A autoreceptor. These results emphasize an original role of hippocampal astrocytes in the synthesis of BDNF, which can act through neurogenesis-dependent and -independent mechanisms to regulate different facets of anxiolytic-like responses.

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A major event during the growth period of oocytes in nonmammalian animals is the accumulation of yolk. The genes coding for the yolk protein precursor, known as vitallogenin, are well characterized in a few vertebrate and invertebrate species. Studies on the evolution of these genes and on the regulatory mechanisms involved in their time, tissue- and hormone-specific expression are presented and discussed in this review.

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Cancer-related inflammation has emerged in recent years as a major event contributing to tumor angiogenesis, tumor progression and metastasis formation. Bone marrow-derived and inflammatory cells promote tumor angiogenesis by providing endothelial progenitor cells that differentiate into mature endothelial cells, and by secreting pro-angiogenic factors and remodeling the extracellular matrix to stimulate angiogenesis though paracrine mechanisms. Several bone marrow-derived myelonomocytic cells, including monocytes and macrophages, have been identified and characterized by several laboratories in recent years. While the central role of these cells in promoting tumor angiogenesis, tumor progression and metastasis is nowadays well established, many questions remain open and new ones are emerging. These include the relationship between their phenotype and function, the mechanisms of pro-angiogenic programming, their contribution to resistance to anti-angiogenic treatments and to metastasis and their potential clinical use as biomarkers of angiogenesis and anti-angiogenic therapies. Here, we will review phenotypical and functional aspects of bone marrow-derived myelonomocytic cells and discuss some of the current outstanding questions.

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BACKGROUND: Clinical scores may help physicians to better assess the individual risk/benefit of oral anticoagulant therapy. We aimed to externally validate and compare the prognostic performance of 7 clinical prediction scores for major bleeding events during oral anticoagulation therapy. METHODS: We followed 515 adult patients taking oral anticoagulants to measure the first major bleeding event over a 12-month follow-up period. The performance of each score to predict the risk of major bleeding and the physician's subjective assessment of bleeding risk were compared with the C statistic. RESULTS: The cumulative incidence of a first major bleeding event during follow-up was 6.8% (35/515). According to the 7 scoring systems, the proportions of major bleeding ranged from 3.0% to 5.7% for low-risk, 6.7% to 9.9% for intermediate-risk, and 7.4% to 15.4% for high-risk patients. The overall predictive accuracy of the scores was poor, with the C statistic ranging from 0.54 to 0.61 and not significantly different from each other (P=.84). Only the Anticoagulation and Risk Factors in Atrial Fibrillation score performed slightly better than would be expected by chance (C statistic, 0.61; 95% confidence interval, 0.52-0.70). The performance of the scores was not statistically better than physicians' subjective risk assessments (C statistic, 0.55; P=.94). CONCLUSION: The performance of 7 clinical scoring systems in predicting major bleeding events in patients receiving oral anticoagulation therapy was poor and not better than physicians' subjective assessments.

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During the Early Toarcian, major paleoenvironnemental and paleoceanographical changes occurred, leading to an oceanic anoxic event (OAE) and to a perturbation of the carbon isotope cycle. Although the standard biochronology of the Lower Jurassic is essentially based upon ammonites, in recent years biostratigraphy based on calcareous nannofossils and dinoflagellate cysts is increasingly used to date Jurassic rocks. However, the precise dating and correlation of the Early Toarcian OAE, and of the associated delta C-13 anomaly in different settings of the western Tethys, are still partly problematic, and it is still unclear whether these events are synchronous or not. In order to allow more accurate correlations of the organic rich levels recorded in the Lower Toarcian OAE, this account proposes a new biozonation based on a quantitative biochronology approach, the Unitary Associations (UA), applied to calcareous nannofossils. This study represents the first attempt to apply the UA method to Jurassic nannofossils. The study incorporates eighteen sections distributed across western Tethys and ranging from the Pliensbachian to Aalenian, comprising 1220 samples and 72 calcareous nannofossil taxa. The BioGraph [Savary, J., Guex, J., 1999. Discrete biochronological scales and unitary associations: description of the Biograph Computer program. Memoires de Geologie de Lausanne 34, 282 pp] and UA-Graph (Copyright Hammer O., Guex and Savary, 2002) softwares provide a discrete biochronological framework based upon multi-taxa concurrent range zones in the different sections. The optimized dataset generates nine UAs using the co-occurrences of 56 taxa. These UAs are grouped into six Unitary Association Zones (UA-Z), which constitute a robust biostratigraphic synthesis of all the observed or deduced biostratigraphic relationships between the analysed taxa. The UA zonation proposed here is compared to ``classic'' calcareous nannofossil biozonations, which are commonly used for the southern and the northern sides of Tethys. The biostratigraphic resolution of the UA-Zones varies from one nannofossil subzone or part of it to several subzones, and can be related to the pattern of calcareous nannoplankton originations and extinctions during the studied time interval. The Late Pliensbachian - Early Toarcian interval (corresponding to the UA-Z II) represents a major step in the Jurassic nannoplankton radiation. The recognized UA-Zones are also compared to the carbon isotopic negative excursion and TOC maximum in five sections of central Italy, Germany and England, with the aim of providing a more reliable correlation tool for the Early Toarcian OAE, and of the associated isotopic anomaly, between the southern and northern part of western Tethys. The results of this work show that the TOC maximum and delta C-13 negative excursion correspond to the upper part of the UA-Z II (i.e., UA 3) in the sections analysed. This suggests that the Early Toarcian OAE was a synchronous event within the western Tethys. (c) 2006 Elsevier B.V. All rights reserved.

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1.1 SUMMARY The role of the non-specific innate immune system is as important as the elaboration of the adaptive immune system in the initiation of an immune response to pathogens. The role of the Toll-like receptors (TLRs) in the innate immune response to virus and bacterial pathogens is widely recognised, however, little is known about the role of TLRs in host defence against eukaryotic pathogens. Immunologic investigations on the marine model of infection with Leishmania major (L. major) have correlated the outcome of the disease with expansion of different subsets of CD4+ cells, designated Th1 and Th2. The resistance of C57BL/6, CBA and C3H/He mice is linked with an IL-12 driven Th1 response. In BALB/c mice the susceptibility correlates with an IL-4 driven Th2 response. The initial event promoting the development of a Th1 or Th2 response still remains elusive. Recently, the contribution of the TLR signalling pathway in the innate and acquired immune response to infection with the intracellular protozoan parasite L. major has been demonstrated. Thus, the purpose of this study is to determine whether TLRs may play a role in influencing the outcome of the infection by directing the development of a Th1 or a Th2 response during infection with L, major parasites, in resistant C57BL/6 and susceptible BALB/c mice, respectively. We demonstrated that MyD88, the major TLR adaptor molecule is necessary for C57BL/6 to develop a resistant Th1 response following L. major infection. Our data show the essential role of MyD88 in the establishment of a protective Th1 response. We subsequently aimed to determine which TLRs may be involved in the protective response. Since TLR2 and TLR4 have shown to have a potential role for Leishmania recognition, we analysed the course of infection in TLR2 and TLR4 deficient mice on a C57BL/6 resistant background following L. major infection. Our results clearly demonstrate that TLR2 or TLR4 aze dispensable to control the outcome of the disease as the TLR2 and TLR4 knockout mice developed a protective Th1 response. With the aim of determining a potential TLR candidate important in the initiation of the Thl response, we assessed the mRNA expression of different TLRs (TLR1 to TLR9) using quantitative real-time RT-PCR at different time points during the first week of infection. The results clearly showed an upregulation of TLR7 and TLR9 mRNA expression during the early phase of infection in resistant C57BL/6 mice but not in susceptible BALB/c mice. To provide in vivo evidence for the role for, these TLRs in the outcome of cutaneous leishmaniasis, studies using TLR7 and TLR9 deficient mice on a resistant C57BL/6 background were performed. The TLR7 deficient mice developed a resistance phenotype that was comparable with C57BL/6 wild type mice. Thus, the presence of TLR7 is not indispensable for the development of a Th1 response and resistance to infection. On the contrary, TLR9 deficient mice on the C57BL/6 resistant background showed high variability in the outcome of the disease. Although some mice behave as resistant C57BL/6 mice, half of them developed high lesion following infection and showed a decrease in IFN-γ production and an increase in IL-4 as compared to wild type mice. These results suggest that TLR9 may be involved in the control of infection. To test the hypothesis that regulatory T cells (Treg) are playing a role in the high variability in the disease outcome in TLR9 deficient mice, depletion of CD4+CD25+ T cells with a specific antibody three days before infection with L. major were performed Interestingly, these treated mice developed large lesions, low IL-4 and decreased IFN-γ producion when compared to untreated mice. A better understanding of the mechanism by which Treg cells influence the outcome of the disease in TLR9 deficient mice following L. major infection is currently under investigation. Altogether, this study demonstrates the importance of TLR9 in the induction of a protective T'h1 response, a process that is involved in the resolution of the lesion induced by L. major infection. 1.2 RÉSUMÉ Le rôle de la réponse immunitaire innée a longtemps été négligé quant à l'impact qu'elle pourrait avoir dans l'initiation d'une réponse immune adaptative efficace dirigée contre un pathogène. Si l'importance des récepteurs Toll-like (TLR) du système inné dans la reconnaissance des virus et bactéries a été démontrée, son rôle dans la défense contre les pathogènes eucaryotes reste encore très élusif. Récemment, il a été montré que les voies de signalisation provenant de l'activation des TLRs pouvaient initier la réponse immunitaire innée et adaptative après une infection avec le parasite protozoaire Leishmania major (L. major). Dans un modèle marin d'infection avec L. major alors que la plupart des souches de souris telles que C57BL/6 sont résistantes à l'infection et développent une réponse immunitaire de type T helper 1 (Th1) induite par IL-12, peu de souches dont les BALB/c sont sensibles et développent une réponse Th2 induite par IL-4. La différentiation Th1/Th2 est un événement qui prend place de manière définitive lors de la première semaine après infection. Les événements précoces promouvant le développement d'une réponse Th1 ou Th2 n'étant pas connus, l'objectif de ce travail a été de démontrer un rôle des TLRs dans l'initiation d'une réponse immune innée et adaptative suite à l'infection par L. major. Nous avons démontré que MyD88, une molécule importante dans le processus de signalisation des TLRs, est nécessaire pour que les souris résistantes C57BL/6 développent une réponse Th1 protectrice. L'importance du rôle de TLR2 et TLR4 dans la reconnaissance du parasite Leishmania ayant été démontrée, nous avons privilégié l'analyse de la réponse immunitaire suite à une infection in vivo de souris déficiente en TLR2 ou TLR4 sur un fond génétique résistant. Les résultats obtenus montrent que la présence de ces récepteurs n'est pas indispensable pour le contrôle de l'infection et la polarisation d'une réponse Th1 caractéristique de la résistance à L. major. Cependant d'autres TLRs peuvent aussi activer la voie de signalisation MyD88 dépendante. L'expression de l'ARNm des différents TLRs dans les ganglions drainant de souris sensibles et résistantes pendant la première semaine d'infection a été déterminée par PCR quantitative en temps réel. Les résultats obtenus montrent que l'ARNm de TLR7 et TLR9 était régulé positivement suite à l'infection par L. major chez les souris résistantes C57BL/6 alors qu'aucune modulation n'était détectable chez les souris sensibles BALB/c. Le rôle des récepteurs TLR7 et TLR9 a donc été évalué par l'infection par L. major des souris déficientes en TLR7 et TLR9 sur fond génétique C57BL/6. Nos résultats ont clairement démontré que les souris déficientes en TLR7 montrent une réponse immunitaire identique à celle des souris résistantes C57BL/6, signifiant que TLR7 n'est pas indispensable au développement d'une Th1 ainsi qu'au contrôle de la parasitémie. Paz contre, les souris déficientes en TLR9 sur un fond génétique résistant ont montré une grande variabilité dans la réponse à l'infection. En effet, la moitié des souris deviennent sensibles à l'infection, ceci étant associé à une diminution dans la production d'IFN-γ et à une augmentation de la production d'IL-4. Ces résultats suggèrent que TLR9 est impliqué dans le contrôle de la lésion et de la réponse immunitaire suite à l'infection avec L. major. Cependant les résultats avec les souris déficientes en TLR9 montrant une grande hétérogénéité et une balance Th1/Th2 instable, nous avons émis l'hypothèse que les cellules T régulatrices pouvaient être impliquées dans ce phénomène. Nous avons effectivement constaté qu'après déplétion des cellules CD4+CD25+, les souris déficientes en TLR9 développent des lésions aussi grandes que les souris BALB/c après infection par L. major. Cependant le nombre de parasites reste le même que chez les souris C57BL/6. De plus la production d'IL-4 ainsi que celle d'IFN-γ reste extrêment bas. Les mécanismes régulateurs impliqués dans ce processus sont en cours d'analyse. Ce travail met en évidence l'importance du TLR9 dans le développement d'une réponse Th1 lors d'une infection avec L. major, un processus nécessaire pour la résistance à l'infection. 1.3 RESUME POUR UN LARGE PUBLIC La leishmaniose est une maladie parasitaire répandue dans le monde entier et touchant plus de 88 pays. L'incidence mondiale de la leishmaniose cutanée et de 1 à 1,5 million de nouveaux cas par année. Plus de 12 millions de personnes sont affectées par la maladie et 350 millions de personnes sont une population à risque. Un modèle marin d'infection avec Leishmania major (L. major) a été établi qui reproduit plusieurs tableaux cliniques observés dans le cas de la leishmaniose cutanée chez l'homme. L'analyse de la réponse immunitaire dans les souris infectées par L. major a permis de distinguer deux groupes : les souris de la plupart des souches telles que C57BL/6 sont résistantes à l'infection et développent une réponse immunitaire de type T helper 1 (Th1), alors que quelques souches dont les BALB/c sont sensibles et développent une réponse de type Th2. La réponse immune adaptative dans le modèle d'infection avec L. major à été largement étudiée. Cependant, les événements précoces déterminants pour le développement d'une réponse Th1 ou Th2 restent encore très flous. Récemment, plusieurs publications ont montré que les récepteurs Toll-like (TLR) peuvent contribuer à l'initiation de la réponse immunitaire lors d'une infection avec le parasite intracellulaire L. major. Dans ce travail de thèse, nous avons étudié le rôle de MyD88, une molécule importante dans le processus de signalisation des TLRs, dans la réponse immune suite à une infection avec L. major. En l'absence de MyD88, les souris normalement résistantes à l'infection avec L. major deviennent sensibles et développent des lésions importantes. Ces souris ne sont plus capables de développer une réponse Thl, normalement caractéristique de leur phénotype résistant. Nous avons ensuite tenté de comprendre quels TLRs, plus précisément, pouvait être impliqué dans ce processus. Malgré quelques évidences démontrant que TLR2 et TLR4 pouvaient avoir un rôle important dans l'initiation d'une réponse immunitaire adaptative à Leishmania, nous avons montré que, in vivo après infection avec L. major, la déficience d'un de ces récepteurs n'était pas suffisante à faire basculer la réponse immunitaire. Les souris C57BL/6 déficient en TLR2 ou TLR4 peuvent parfaitement contrôler l'évolution de la maladie. De plus, ces souris, malgré l'absence de TLR2 ou TLR4, sont capables de monter une parfaite réponse Thl. Etant donné que TLR2 et TLR4 n'étaient pas essentiels pour la résistance à la maladie, nous avons analysé les TLRs, parmi les 12 décrits qui pouvaient être indispensables au développement d'une réponse de type Th1 associée à la résistance à l'infection par Leishmania. Nos expériences ont montré que l'expression de l'ARN messager (ARNm) de TLR7 et TLR9 était modulée suite à l'infection par L. major chez la souris résistante C57BL/6 alors qu'aucune modulation n'était visible chez les souris sensible BALB/c. Pensant que ces TLRs pourraient jouer un rôle dans la réponse immunitaire au parasite, nous avons étudié l'évolution de l'infection dans les souris déficientes en TLR7 et TLR9. Nos résultats ont clairement démontré que TLR7 n'était pas indispensable à la résistance au parasite alors que l'absence de TLR9 avait des conséquences radicales sur le contrôle de la lésion et de la réponse immunitaire suite à l'infection avec L. major. Ce travail révèle ainsi l'importance du TLR9 dans le développement d'une réponse Th1 lors d'une infection avec L. major, un processus nécessaire pour la résistance à l'infection. Il est a noté que nos résultats sont en accord avec le fait que les motifs CpG, qui sont des immunostimulateurs interagissant avec le TLR9, ont une activité adjuvante importante dans la préparation de vaccins contre la leishmaniose. Une meilleure compréhension des mécanismes immunologiques impliquant le TLR9 dans la reconnaissance du parasite est alors indispensable pour le développement de vaccins thérapeutiques efficaces.

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OBJECTIVES: This study was designed to assess the prevalence of major cardiovascular risk factors in familial premature coronary artery disease (P-CAD), affecting two or more siblings within one sibship. BACKGROUND: Premature CAD has a genetic component. It remains to be established whether familial P-CAD is due to genes acting independently from major cardiovascular risk factors. METHODS: We recruited 213 P-CAD survivors from 103 sibships diagnosed before age <or=50 (men) or <or=55 (women) years old. Hypertension, hypercholesterolemia, obesity, and smoking were documented at the time of the event in 163 patients (145 men and 18 women). Each patient was compared with two individuals of the same age and gender, diagnosed with sporadic (nonfamilial) P-CAD, and three individuals randomly sampled from the general population. RESULTS: Compared with the general population, patients with sporadic P-CAD had a higher prevalence of hypertension (29% vs. 14%, p < 0.001), hypercholesterolemia (54% vs. 33%, p < 0.001), obesity (20% vs. 13%, p < 0.01), and smoking (76% vs. 39%, p < 0.001). These risk factors were equally or even more prevalent in patients with familial P-CAD (43% [p < 0.05 vs. sporadic P-CAD], 58% [p = 0.07], 21% and 72%, respectively). Overall, only 7 (4%) of 163 of patients with familial P-CAD and 22 (7%) of 326 of patients with sporadic P-CAD had none of these conditions, as compared with 167 (34%) of 489 patients in the general population. CONCLUSIONS: Classic, remediable risk factors are highly prevalent in patients with familial P-CAD. Accordingly, a major contribution of genes acting in the absence of these risk factors is unlikely.

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In the last decades, the globalized competition among cities and regions made them develop new strategies for branding and promoting their territory to attract tourists, investors, companies and residents. Major sports events - such as the Olympic Games, the FIFA World Cup or World and Continental Championships - have played an integral part in these strategies. Believing, with or without evidence, in the capacity of those events to improve the visibility and the economy of the host destination, many cities, regions and even countries have engaged in establishing sports events hosting strategies. The problem of the globalized competition in the sports events "market" is that many cities and regions do not have the resources - either financial, human or in terms of infrastructure - to compete in hosting major sports events. Consequently, many cities or regions have to turn to second-tier sports events. To organise those smaller events means less media coverage and more difficulty in finding sponsors, while the costs - both financial and in terms of services - stay high for the community. This paper analyses how Heritage Sporting Events (HSE) might be an opportunity for cities and regions engaged in sports events hosting strategies. HSE is an emerging concept that to date has been under-researched in the academic literature. Therefore, this paper aims to define the concept of HSE through an exploratory research study. A multidisciplinary literature review reveals two major characteristics of HSEs: the sustainability in the territory and the authenticity of the event constructed through a differentiation process. These characteristics, defined through multiple variables, give us the opportunity to observe the construction process of a sports event into a heritage object. This paper argues that HSEs can be seen as territorial resources that can represent a competitive advantage for host destinations. In conclusion, academics are invited to further research HSEs to better understand their construction process and their impacts on the territory, while local authorities are invited to consider HSEs for the branding and the promotion of their territory.

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Résumé Objectifs: Cette étude relève la prévalence des principaux facteurs de risque cardiovasculaire dans les coronaropathies précoces (P-CAD) familiales, survenant chez au moins deux frères et/ou soeurs d'une même fratrie. Méthodes: Nous avons recruté 213 survivants atteints de P-CAD, issus de 103 fratries, diagnostiqués avant l'âge de 50 ans chez les hommes et 55 ans chez les femmes. La présence ou non d'hypertension, d'hypercholestérolémie, d'obésité et de tabagisme a été documentée au moment de l'événement chez 163 de ces patients (145 hommes et 18 femmes). Chaque patient a été comparé à deux individus de même âge et sexe, chez qui un diagnostic de P-CAD «sporadique» (non familiale) était posé, et à trois individus choisis au hasard parmi la population générale. Résultats: En comparaison de la population générale, les patients atteints de P-CAD sporadique avaient une prévalence supérieure pour l 'hypertension (29% vs. 14%, p<0.001), le cholestérol (54% vs. 33%, p<0.001), l'obésité (20% vs. 13%, p<0.001) et le tabagisme (76% vs. 39%, p<0.001). Ces facteurs de risque étaient de prévalences similaires, voire supérieures chez les patients atteints de P-CAD familiale (43% [p0.05 vs. P-CAD sporadiques], 58% [p=0.07], 21% et 72% respectivement). Seulement 7 (4%) des 163 patients atteints de P-CAD familiale et 22 (7%) des 326 patients atteints de P-CAD sporadique, ne présentaient aucun facteur de risque cardiovasculaire, comparés à 167 (34%) des 489 patients issus de la population générale. Conclusions: Les facteurs de risque cardiovasculaire classiques et réversibles ont une haute prévalence chez les patients atteints de P-CAD familiale. Ce fait rend improbable une contribution génétique prédominante, agissant en l'absence de facteurs de risque. Summary Objectives: This study was designed to assess the prevalence of major cardiovascular risk factors in familial premature coronary artery disease (P-CAD), affecting two or more siblings within one sibship. Background: Premature CAD has a genetic component. It remains to be established whether familial P-CAD is due to genes acting independently from major cardiovascular risk factors. Methods: We recruited 213 P-CAD survivors from 103 sibships diagnosed before age ?50 (men) or ?55 (women) years old. Hypertension, hypercholesterolemia, obesity, and smoking were documented at the time of the event in 163 patients (145 men and 18 women). Each patient was compared with two individuals of the same age and gender, diagnosed with sporadic (nonfamilial) P-CAD, and three individuals randomly sampled from the general population. Result: Compared with the general population, patients with sporadic P-CAD had a higher prevalence of hypertension (29% vs. 14%, p < 0.001), hypercholesterolemia (54% vs. 33%, p < 0.001), obesity (20% vs. 13%, p < 0.01), and smoking (76% vs. 39%, p < 0.001). These risk factors were equally or even more prevalent in patients with familial P-CAD (43% [p < 0.05 vs. sporadic P-CAD], 58% [p = 0.07], 21% and 72%, respectively). Overall, only 7 (4%) of 163 of patients with familial P-CAD and 22 (7%) of 326 of patients with sporadic P-CAD had none of these conditions, as compared with 167 (34%) of 489 patients in the general population. Conclusions: Classic, remediable risk factors are highly prevalent in patients with familial P-CAD. Accordingly, a major contribution of genes acting in the absence of these risk factors is unlikely.

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Diversity patterns of ammonoids are analyzed and compared with the timing of anoxic deposits around the Cenomanian/Turonian (C/T) boundary in the Vocontian, Anglo-Paris, and Monster basins of Western Europe. Differing from most previous studies, which concentrate on a narrow time span bracketing the C/T boundary, the present analysis covers the latest Albian to Early Turonian interval for which a high resolution, ammonoid-based biochronology, including 34 Unitary Associations zones, is now available. During the latest Albian-Middle Cenomanian interval, species richness of ammonoids reveals a dynamical equilibrium oscillating around an average of 20 species, whereas the Late Cenomanian-Early Turonian interval displays an equilibrium centered on an average value of 6 species. The abrupt transition between these two successive equilibria lasted no longer than two Unitary Associations. The onset of the decline of species richness thus largely predates the spread of oxygen-poor water masses onto the shelves, while minimal values of species richness coincide with the Cenomanian-Turonian boundary only. The decline of species richness during the entire Late Cenomanian seems to result from lower origination percentages rather than from higher extinction percentages. This result is also supported by the absence of statistically significant changes in the extinction probabilities of the poly-cohorts. Separate analyses of species richness for acanthoceratids and heteromorphs, the two essential components of the Cenomanian ammonoid community, reveal that heteromorphs declined sooner than acanthoceratids. Moreover, acanthoceratids showed a later decline at the genus level than at the species level. Such a decoupling is accompanied by a significant increase in morphological disparity of acanthoceratids, which is expressed by the appearance of new genera. Last, during the Late Cenomanian, paedomorphic processes, juvenile innovations and reductions of adult size dominated the evolutionary radiation of acanthoceratids. Hence, the decrease in ammonoid species richness and their major evolutionary changes significantly predates the spread of anoxic deposits. Other environmental constraints such as global flooding of platforms, warmer and more equable climate, as well as productivity changes better correlate with the timing of diversity changes and evolutionary patterns of ammonoids and therefore, provide more likely causative mechanisms than anoxia alone.

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Elevated low-density lipoprotein (LDL) levels induce activation of the p38 mitogen-activated protein kinase (MAPK), a stress-activated protein kinase potentially participating in the development of atherosclerosis. The nature of the lipoprotein components inducing p38 MAPK activation has remained unclear however. We show here that both LDLs and high-density lipoproteins (HDLs) have the ability to stimulate the p38 MAPKs with potencies that correlate with their cholesterol content. Cholesterol solubilized in methyl-beta-cyclodextrin was sufficient to activate the p38 MAPK pathway. Liposomes made of phosphatidylcholine (PC) or sphingomyelin, the two main phospholipids found in lipoproteins, were unable to stimulate the p38 MAPKs. In contrast, PC liposomes loaded with cholesterol potently activated this pathway. Reducing the cholesterol content of LDL particles lowered their ability to activate the p38 MAPKs. Cell lines representative of the three main cell types found in blood vessels (endothelial cells, smooth muscle cells and fibroblasts) all activated their p38 MAPK pathway in response to LDLs or cholesterol-loaded PC liposomes. These results indicate that elevated cholesterol content in lipoproteins, as seen in hypercholesterolemia, favors the activation of the stress-activated p38 MAPK pathway in cells from the vessel wall, an event that might contribute to the development of atherosclerosis.

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High-resolution seismic and sediment core data from the 'Grand Lac' basin of Lake Geneva reveal traces of repeated slope instabilities with one main slide-evolved mass-flow (minimum volume 0.13 km3) that originated from the northern lateral slope of the lake near the city of Lausanne. Radiocarbon dating of organic remains sampled from the top of the main deposit gives an age interval of 1865-1608 BC. This date coincides with the age interval for a mass movement event described in the 'Petit Lac' basin of Lake Geneva (1872-1622 BC). Because multiple mass movements took place at the same time in different parts of the lake, we consider the most likely trigger mechanism to be a strong earthquake (Mw 6) that occurred in the period between 1872 and 1608 BC. Based on numerical simulations, we show the major deposit near Lausanne would have generated a tsunami with local wave heights of up to 6 m. The combined effects of the earthquake and the following tsunami provide a possible explanation for a gap in lake dwellers occupation along the shores of Lake Geneva revealed by dendrochronological dating of two palafitte archaeological sites.

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Résumé: Objectifs: Cette étude relève la prévalence des principaux facteurs de risque cardiovasculaire dans les coronaropathies précoces (P-CAD) familiales, survenant chez au moins deux frères et/ou soeurs d'une même fratrie. Méthodes: Nous avons recruté 213 survivants atteints de P-CAD, issus de 103 fratries, diagnostiqués avant l'âge de 50 ans chez les hommes et 55 ans chez les femmes. La présence ou non d'hypertension, d'hypercholestérolémie, d'obésité et de tabagisme a été documentée au moment de l'événement chez 163 de ces patients (145 hommes et 18 femmes). Chaque patient a été comparé à deux individus de même âge et sexe, chez qui un diagnostic de P-CAD «sporadique» (non familiale) était posé, et à trois individus choisis au hasard parmi la population générale. Résultats: En comparaison de la population générale, les patients atteints de P-CAD sporadique avaient une prévalence supérieure pour 1 'hypertension (29% vs. 14%, p<0.001), le cholestérol (54% vs. 33%, p<0.001), l'obésité (20% vs. 13%, p<0.001) et le tabagisme (76% vs. 39%, p<0.001). Ces facteurs de risque étaient de prévalences similaires, voire supérieures chez les patients atteints de P-CAD familiale (43% [p<0.05 vs. P-CAD sporadiques], 58% [p=0.07], 21% et 72%) respectivement). Seulement 7 (4%) des 163 patients atteints de P-CAD familiale et 22 (7%) des 326 patients atteints de P-CAD sporadique, ne présentaient aucun facteur de risque cardiovasculaire, comparés à 167 (34%) des 489 patients issus de la population générale. Conclusions: Les facteurs de risque cardiovasculaire classiques et réversibles ont une haute prévalence chez les patients atteints de P-CAD familiale. Ce fait rend improbable une contribution génétique prédominante, agissant en l'absence de facteurs de risque. Abstract: Objectives: This study was designed to assess the prevalence of major cardiovascular risk factors in familial premature coronary artery disease (P-CAD), affecting two or more siblings within one sibship. Background: Premature CAD has a genetic component. It remains to be established whether familial P-CAD is due to genes acting independently from major cardiovascular risk factors. Methods: We recruited 213 P-CAD survivors from 103 sibships diagnosed before age ?50 (men) or ?55 (women) years old. Hypertension, hypercholesterolemia, obesity, and smoking were documented at the time of the event in 163 patients (145 men and 18 women). Each patient was compared with two individuals of the same age and gender, diagnosed with sporadic (nonfamilial) P-CAD, and three individuals randomly sampled from the general population. Results: Compared with the general population, patients with sporadic P-CAD had a higher prevalence of hypertension (29% vs. 14%, p < 0.001), hypercholesterolemia (54% vs. 33%, p < 0.001), obesity (20% vs. 13%, p < 0.001), and smoking (76% vs. 39%, p < 0.001). These risk factors were equally or even more prevalent in patients with familial P-CAD (43% [p < 0.05 vs. sporadic P-CAD], 58% [p = 0.07], 21% and 72%, respectively). Overall, only 7 (4%) of 163 of patients with familial P-CAD and 22 (7%) of 326 of patients with sporadic P-CAD had none of these conditions, as compared with 167 (34%) of 489 patients in the general population. Conclusions: Classic, remediable risk factors are highly prevalent in patients with familial P-CAD. Accordingly, a major contribution of genes acting in the absence of these risk factors is unlikely

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The interfaces between the intrapsychic, interactional, and intergenerational domains are a new frontier. As a pilot, we exposed ourselves to a complex but controllable situation as viewed by people whose main interest is in one of the three interfaces; we also fully integrated the subjects in the team, to learn about their subjective perspectives and to provide them with an enriching experience. We started with a brief "triadification" sequence (i.e., moving from a "two plus one" to a "three together" family organization). Considering this sequence as representing at a micro level many larger family transitions, we proceeded with a microanalytic interview, a psychodynamic investigation, and a family interview. As expected, larger patterns of correspondences are emerging. Central questions under debate are: What are the most appropriate units at each level of description and what are their articulations between these levels? What is the status of "triadification"? Les interfaces entre les domaines intrapsychiques, interactionnels et intergénérationnels représentent une nouvelle frontiére. A titre exploratoire, nous nous sommes exposés à une situation complexe mais contrǒlable ainsi que le voient ceux dont I'intérět principal se porte sur l'une de ces trois interfaces. Nous avons aussi entièrement intégré les sujets dans l'équipe, de facon à comprendre leur perspective subjective et à leur offrir une expérience enrichissante. Nous avons commencé avec une brève séquence de "triadification," c'est-à-dire passer d'une organisation familiale "deux plus un" à Ltne organisation familiale "trois (add sentenc)ensemble." Considérant cette séquence comme representative à un niveau microscopique de transitions familiales bien plus larges, nous avons procedé à l'entretien microanalytique, à une enquěte psychodynamique et à un entretien familial. Comme prévu, de grands patterns de correspondances émergent. Les questions essentielles sur lesquelles portent le débat sont: quelles les unités les plus appropiées à chaque niveau de description et quelles sont les articulations entre ces niveaux? Quel est le statut de la "triadification"?