[Do smokers and potential smokers have to be offended in order to be dissuaded from smoking? The effectiveness of anti-smoking pictograms]. / Faut-il choquer les fumeurs et les fumeurs potentiels pour dissuader les comportements tabagiques ? Efficacité des pictogrammes contre le tabagisme.

BACKGROUND: As recommended by WHO in the fight against smoking, the French authorities have decided to implement the display of 14 "shock pictures" on cigarette packages in 2011. This study examines the effectiveness of this policy. METHODS: The present study is based on a self-reported questionnaire administered to a sample of 418 first-year medical students from a private faculty in January 2010. We consider a set of 12 European visual warnings that address different smoking problems. Econometric modeling is used to study the determinants of answers. RESULTS: Our results were twofold. Firstly, the most effective symbols concern the smoker himself/herself, they are explicit and related to an advanced stage of disease. Secondly, the warnings seem to be more effective to confirm the non-smokers in their choice than to deter smokers to smoke. CONCLUSION: This tobacco control policy seems to be effective. Therefore, visual warnings have to be carefully chosen before implementation.

Origin differences in self-reported health among older migrants living in France.

OBJECTIVES: Little is known about the health status of older migrants living in Europe. Using detailed data collected in 2003, this study investigated differences in health status by country of origin within the older immigrant population living in France using a self-rated health measure. STUDY DESIGN: The database used in this research was the Passage à la Retraite des Immigrés survey, conducted from November 2002 to February 2003 on a sample of 6211 migrants aged 45-70 years and living in France at the time of the survey. METHODS: A difficulty with a self-rated outcome is that it may not be comparable between different origin groups, particularly because of cultural and linguistic differences. Therefore, generalized ordered Probit models were estimated, and an indicator of health, net of cross-cultural effects was constructed for each respondent. RESULTS: This study found that male immigrants from southern Africa and Asia, and female immigrants from northern Europe, southern Africa and Asia are more likely to be in good health, while the health status is lower among immigrants from Eastern Europe living in France. CONCLUSION: The diversity in health status within the immigrant population is large in France. These results are helpful in order to target the more disadvantaged origin groups and to adjust the provision of health care.

Alteration of photosynthesis in grapevines affected by esca.

ABSTRACT To further understand the development of esca disease in grapevine, its physiological impact on plants grown in the vineyard was characterized, focusing mainly on photosynthesis. For this purpose, the state of the photosynthetic apparatus was evaluated in symptomatic and asymptomatic leaves in esca-infected grape plants, and wood carbohydrates stored in annual canes were assayed. In symptomatic leaves, esca greatly affected grapevine physiology. Foliar symptoms were associated with both stomatal closure and alteration of the photosynthetic apparatus as revealed by (i) a decrease in CO(2) assimilation, transpiration, and a significant increase in intercellular CO(2) concentration; (ii) a strong drop in both the maximum fluorescence yield and the effective Photosystem II quantum yield; and (iii) a reduction of total chlorophyll but a stable carotenoid content. On symptomatic canes, all these variables were affected more on leaves with symptoms than without symptoms, suggesting a gradation in photosynthesis disruptions in the plant according to the degree of symptom severity. In addition, canes of symptomatic plants had reduced carbohydrate reserves during the winter rest, whether they exhibit symptoms or not. The following year, the lower pool of reserves may contribute to a significant decrease in plant development, as well as a global loss in plant vigor.

Comparative study of responses in four Datura species to a zinc stress.

The effects of zinc toxicity on the growth and the photosynthetic activities of four Datura species (Datura metel, Datura innoxia, Datura sanguinea, Datura tatula) were studied using various ZnSO4 concentrations (0, 1, 2.5 and 5 mM) added in the Coic Lessaint solution. Growth, photosynthesis, chlorophyll fluorescence and chlorophyll concentration were measured after 20 days of zinc stress. These parameters were severely reduced by this heavy metal. The zinc excess involves the stomate closing, the increase of CO2 concentration in the leaves, the inhibition of certain enzyme of the Calvin cycle, a degradation of photosystem and the chlorophyll decomposition. These phenomena allow the decrease of the net photosynthesis to be partially explained. These key parameters to assess photosynthetic performance allow the plants to be classified according to their resistance to zinc. Compared with the three other species, D. innoxia showed a very strong capacity to protect itself against toxic zinc concentrations; a large amount of ZnSO4 (5 mM) was required to inhibit 43% of the photosynthesis.

Modulation of RhoA-Rho kinase-mediated Ca2+ sensitization of rabbit myometrium during pregnancy - role of Rnd3.

During pregnancy, the uterus undergoes major functional and structural remodelling. It is well known that during the major part of pregnancy, the myometrium normally remains relatively quiescent but is able to generate powerful contractions at the time of parturition. However, the intracellular molecular events regulating myometrial contractility during pregnancy still remain poorly understood. We applied differential gene expression screening using cDNA array technology to probe myometrium samples from non-pregnant and mid-pregnant (15 days) rabbits. Among the differentially expressed genes, the farnesylated small G-protein of the Rho family, Rnd3, was found to be upregulated (3.6-fold) at mid-pregnancy. Upregulation of Rnd3 was confirmed at the protein level by a 3.4-fold increase in Rnd3 expression in mid-pregnant myometrium. Measurements of contractile properties of beta-escin permeabilized smooth muscle strips revealed that the upregulation of Rnd3 correlated with an inhibition of RhoA-Rho kinase-mediated Ca2+ sensitization at mid-pregnancy. Treatment of muscle strips from mid-pregnant myometrium with the farnesyl-transferase inhibitor manumycin A (10 muM) led to the recovery of RhoA-Rho kinase-dependent Ca2+ sensitization. At late pregnancy (31 days), upregulation of RhoA and Rho kinase expression was associated with an increase in Ca2+ sensitivity of contractile proteins that was inhibited by the Rho kinase inhibitor Y-27632 (10 muM). These data thus demonstrate the time-dependent regulation of the RhoA-Rho kinase-mediated Ca2+ sensitization during the course of pregnancy. The depression of this mechanism at mid-pregnancy followed by its constitutive activation near term is associated with a co-ordinated modulation of Rnd3, RhoA and Rho kinase expression. The RhoA-Rho kinase signalling pathway and its regulators might thus represent potential targets for the development of new treatments for pre-term labour.

P2Y(1), P2Y(2), P2Y(4), and P2Y(6) receptors are coupled to Rho and Rho kinase activation in vascular myocytes.

In the cardiovascular system, activation of ionotropic (P2X receptors) and metabotropic (P2Y receptors) P2 nucleotide receptors exerts potent and various responses including vasodilation, vasoconstriction, and vascular smooth muscle cell proliferation. Here we examined the involvement of the small GTPase RhoA in P2Y receptor-mediated effects in vascular myocytes. Stimulation of cultured aortic myocytes with P2Y receptor agonists induced an increase in the amount of membrane-bound RhoA and stimulated actin cytoskeleton organization. P2Y receptor agonist-induced actin stress fiber formation was inhibited by C3 exoenzyme and the Rho kinase inhibitor Y-27632. Stimulation of actin cytoskeleton organization by extracellular nucleotides was also abolished in aortic myocytes expressing a dominant negative form of RhoA. Extracellular nucleotides induced contraction and Y-27632-sensitive Ca(2+) sensitization in aortic rings. Transfection of Swiss 3T3 cells with P2Y receptors showed that Rho kinase-dependent actin stress fiber organization was induced in cells expressing P2Y(1), P2Y(2), P2Y(4), or P2Y(6) receptor subtypes. Our data demonstrate that P2Y(1), P2Y(2), P2Y(4), and P2Y(6) receptor subtypes are coupled to activation of RhoA and subsequently to Rho-dependent signaling pathways.

Riluzole prevents ischemic spinal cord injury caused by aortic crossclamping.

BACKGROUND: Recent studies support the involvement of glutamate neurotoxicity in the pathophysiology of spinal cord injury induced by aortic crossclamping. We investigated the effects of riluzole, a neuroprotective drug that blocks glutamatergic neurotransmission, in a rabbit model of spinal cord ischemia. METHODS: The infrarenal aortas of New Zealand White albino rabbits (n = 40) were occluded for 40 minutes. Experimental groups were as follows: sham operation group (n = 5), control group undergoing occlusion but receiving no pharmacologic intervention (n = 10), experimental group A (n = 10) receiving 8 mg/kg riluzole intravenously 30 minutes before ischemia, experimental group B (n = 10) receiving 4 mg/kg riluzole intravenously 30 minutes before ischemia and at the onset of reperfusion, and experimental group C (n = 10) receiving 8 mg/kg riluzole intravenously at the onset of reperfusion. Neurologic status was assessed at 6, 24, and 48 hours after the operation and then daily until the fifth day. All animals were killed at 24, 48, or 120 hours after the operation. Spinal cords were harvested for histopathologic studies, immunohistochemical studies for microtubule-associated protein 2, and search for morphologic features of apoptosis by the terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate-biotin nick-end labeling staining method. RESULTS: All animals in the control group became paraplegic. Except for 1 rabbit in group C, all riluzole-treated animals had better neurologic function. Luxol fast blue and terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate-biotin nick-end labeling staining methods demonstrated typical morphologic changes characteristic of necrosis and apoptosis in control animals. Riluzole prevented or attenuated ischemia-induced necrosis, apoptosis, and cytoskeletal proteolysis, depending on the dose and the timing of administration. CONCLUSION: Riluzole may have therapeutic utility during high-risk operations on the thoracoabdominal aorta.