13 research outputs found

    High-resolution microwave frequency dissemination on an 86-km urban optical link

    Full text link
    We report the first demonstration of a long-distance ultra stable frequency dissemination in the microwave range. A 9.15 GHz signal is transferred through a 86-km urban optical link with a fractional frequency stability of 1.3x10-15 at 1 s integration time and below 10-18 at one day. The optical link phase noise compensation is performed with a round-trip method. To achieve such a result we implement light polarisation scrambling and dispersion compensation. This link outperforms all the previous radiofrequency links and compares well with recently demonstrated full optical links.Comment: 11 pages, 5 figure

    The genetic architecture of the human cerebral cortex

    Get PDF
    INTRODUCTION The cerebral cortex underlies our complex cognitive capabilities. Variations in human cortical surface area and thickness are associated with neurological, psychological, and behavioral traits and can be measured in vivo by magnetic resonance imaging (MRI). Studies in model organisms have identified genes that influence cortical structure, but little is known about common genetic variants that affect human cortical structure. RATIONALE To identify genetic variants associated with human cortical structure at both global and regional levels, we conducted a genome-wide association meta-analysis of brain MRI data from 51,665 individuals across 60 cohorts. We analyzed the surface area and average thickness of the whole cortex and 34 cortical regions with known functional specializations. RESULTS We identified 306 nominally genome-wide significant loci (P < 5 × 10−8) associated with cortical structure in a discovery sample of 33,992 participants of European ancestry. Of the 299 loci for which replication data were available, 241 loci influencing surface area and 14 influencing thickness remained significant after replication, with 199 loci passing multiple testing correction (P < 8.3 × 10−10; 187 influencing surface area and 12 influencing thickness). Common genetic variants explained 34% (SE = 3%) of the variation in total surface area and 26% (SE = 2%) in average thickness; surface area and thickness showed a negative genetic correlation (rG = −0.32, SE = 0.05, P = 6.5 × 10−12), which suggests that genetic influences have opposing effects on surface area and thickness. Bioinformatic analyses showed that total surface area is influenced by genetic variants that alter gene regulatory activity in neural progenitor cells during fetal development. By contrast, average thickness is influenced by active regulatory elements in adult brain samples, which may reflect processes that occur after mid-fetal development, such as myelination, branching, or pruning. When considered together, these results support the radial unit hypothesis that different developmental mechanisms promote surface area expansion and increases in thickness. To identify specific genetic influences on individual cortical regions, we controlled for global measures (total surface area or average thickness) in the regional analyses. After multiple testing correction, we identified 175 loci that influence regional surface area and 10 that influence regional thickness. Loci that affect regional surface area cluster near genes involved in the Wnt signaling pathway, which is known to influence areal identity. We observed significant positive genetic correlations and evidence of bidirectional causation of total surface area with both general cognitive functioning and educational attainment. We found additional positive genetic correlations between total surface area and Parkinson’s disease but did not find evidence of causation. Negative genetic correlations were evident between total surface area and insomnia, attention deficit hyperactivity disorder, depressive symptoms, major depressive disorder, and neuroticism. CONCLUSION This large-scale collaborative work enhances our understanding of the genetic architecture of the human cerebral cortex and its regional patterning. The highly polygenic architecture of the cortex suggests that distinct genes are involved in the development of specific cortical areas. Moreover, we find evidence that brain structure is a key phenotype along the causal pathway that leads from genetic variation to differences in general cognitive function

    Tadalafil-induced Improvement In Left Ventricular Diastolic Function In Resistant Hypertension

    No full text
    Purpose: Left ventricular hypertrophy and diastolic dysfunction (LVDD) remain highly frequent markers of cardiac damage and risk of progression to symptomatic heart failure, especially in resistant hypertension (RHTN). We have previously demonstrated that administration of sildenafil in hypertensive rats improves LVDD, restoring phosphodiesterase type 5 (PDE-5) inhibition in cardiac myocytes. Methods: We hypothesized that the long-acting PDE-5 inhibitor tadalafil may be clinically useful in improving LVDD in RHTN independently of blood pressure (BP) reduction. A single blinded, placebo-controlled, crossover study enrolled 19 patients with both RHTN and LVDD. Firstly, subjects received tadalafil (20 mg) for 14 days and after a 2-week washout period, they received placebo orally for 14 days. Patients were evaluated by office BP and ambulatory BP monitoring (ABPM), endothelial function (FMD), echocardiography, plasma brain natriuretic peptide (BNP-32), cyclic guanosine monophosphate (cGMP) and nitrite levels. Results: No significant differences were detected in BP measurements. Remarkably, at least four echocardiographic parameters related with diastolic function improved accompanied by decrease in BNP-32 in tadalafil use. Although increasing cGMP, tadalafil did not change endothelial function or nitrites. There were no changes in those parameters after placebo. Conclusion: The current findings suggest that tadalafil improves LV relaxation through direct effects PDE-5-mediated in the cardiomyocytes with potential benefit as an adjunct to treat symptomatic subjects with LVDD such as RHTN patients. © 2013 Springer-Verlag Berlin Heidelberg.702147154Calhoun, D.A., Jones, D., Textor, S., Goff, D.C., Murphy, T.P., Toto, R.D., White, A., Carey, R.M., Resistant hypertension: Diagnosis, evaluation, and treatment: A scientific statement from the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research (2008) Circulation, 117, pp. 510-e526. , 18574054 10.1161/CIRCULATIONAHA.108.189141Salles, G.F., Cardoso, C.R., Fiszman, R., Muxfeldt, E.S., Prognostic impact of baseline and serial changes in electrocardiographic left ventricular hypertrophy in resistant hypertension (2010) Am Heart J, 159, pp. 833-840. , 20435193 10.1016/j.ahj.2010.02.012Redfield, M.M., Jacobsen, S.J., Burnett, Jr.J.C., Mahoney, D.W., Bailey, K.R., Rodeheffer, R.J., Burden of systolic and diastolic ventricular dysfunction in the community: Appreciating the scope of the heart failure epidemic (2003) JAMA, 289, pp. 194-202. , 12517230 10.1001/jama.289.2.194Kohno, M., Horio, T., Yokokawa, K., Murakawa, K., Yasunari, K., Akioka, K., Tahara, A., Kurihara, N., Brain natriuretic peptide as a cardiac hormone in essential hypertension (1992) Am J Med, 92, pp. 29-34. , 1:STN:280:DyaK387hslSmtw%3D%3D 1530996 10.1016/0002-9343(92)90011-YUbaid-Girioli, S., Adriana De Souza, L., Yugar-Toledo, J.C., Martins, L.C., Ferreira-Melo, S., Coelho, O.R., Sierra, C., Moreno, H., Aldosterone excess or escape: Treating resistant hypertension (2009) J Clin Hypertens (Greenwich), 11, pp. 245-252. , 1:CAS:528:DC%2BD1MXosVaksrg%3D 10.1111/j.1751-7176.2009.00110.xSchwartz, B.G., Levine, L.A., Comstock, G., Stecher, V.J., Kloner, R.A., Cardiac uses of phosphodiesterase-5 inhibitors (2012) J Am Coll Cardiol, 59, pp. 9-15. , 1:CAS:528:DC%2BC38Xit1Wjsb8%3D 22192662 10.1016/j.jacc.2011.07.051Oliver, J.J., Melville, V.P., Webb, D.J., Effect of regular phosphodiesterase type 5 inhibition in hypertension (2006) Hypertension, 48, pp. 622-627. , 1:CAS:528:DC%2BD28XpsFOrsL8%3D 16940217 10.1161/01.HYP.0000239816.13007. c9Wolk, R., Smith, W.B., Neutel, J.M., Rubino, J., Xuan, D., Mancuso, J., Gilbert, J., Pressler, M.L., Blood pressure lowering effects of a new long-acting inhibitor of phosphodiesterase 5 in patients with mild to moderate hypertension (2009) Hypertension, 53, pp. 1091-1097. , 1:CAS:528:DC%2BD1MXlslCitbk%3D 19398651 10.1161/HYPERTENSIONAHA.109. 132225Oliver, J.J., Hughes, V.E., Dear, J.W., Webb, D.J., Clinical potential of combined organic nitrate and phosphodiesterase type 5 inhibitor in treatment-resistant hypertension (2010) Hypertension, 56, pp. 62-67. , 1:CAS:528:DC%2BC3cXnsFGktbo%3D 20479335 10.1161/HYPERTENSIONAHA.109. 147686Pokreisz, P., Vandenwijngaert, S., Bito, V., Van Den Bergh, A., Lenaerts, I., Busch, C., Marsboom, G., Janssens, S.P., Ventricular phosphodiesterase-5 expression is increased in patients with advanced heart failure and contributes to adverse ventricular remodeling after myocardial infarction in mice (2009) Circulation, 119, pp. 408-416. , 1:CAS:528:DC%2BD1MXpt1Cmsw%3D%3D 3791110 19139381 10.1161/CIRCULATIONAHA. 108.822072Zhang, M., Koitabashi, N., Nagayama, T., Rambaran, R., Feng, N., Takimoto, E., Koenke, T., Kass, D.A., Expression, activity, and pro-hypertrophic effects of PDE5A in cardiac myocytes (2008) Cell Signal, 20, pp. 2231-2236. , 1:CAS:528:DC%2BD1cXhtlCru7vL 2601628 18790048 10.1016/j.cellsig.2008.08. 012Ferreira-Melo, S.E., Demacq, C., Lacchini, S., Krieger, J.E., Irigoyen, M.C., Moreno, H., Sildenafil preserves diastolic relaxation after reduction by L-NAME and increases phosphodiesterase-5 in the intercalated discs of cardiac myocytes and arterioles (2011) Clinics (Sao Paulo), 66, pp. 1253-1258. , 10.1590/S1807-59322011000700022Quinaglia, T., De Faria, A.P., Fontana, V., Barbaro, N.R., Sabbatini, A.R., Sertorio, J.T., Demacq, C., Moreno, H., Acute cardiac and hemodynamic effects of sildenafil on resistant hypertension (2013) Eur J Clin Pharmacol., , In pressDrager, L.F., Genta, P.R., Pedrosa, R.P., Nerbass, F.B., Gonzaga, C.C., Krieger, E.M., Lorenzi-Filho, G., Characteristics and predictors of obstructive sleep apnea in patients with systemic hypertension (2010) Am J Cardiol, 105, pp. 1135-1139. , 20381666 10.1016/j.amjcard.2009.12.017Alessi, A., Brandao, A.A., Coca, A., Cordeiro, A.C., Nogueira, A.R., Diogenes De Magalhaes, F., Amodeo, C., Barroso, W.K., First Brazilian position on resistant hypertension (2012) Arq Bras Cardiol, 99, pp. 576-585. , 22948302 10.1590/S0066-782X2012000700002Corretti, M.C., Anderson, T.J., Benjamin, E.J., Celermajer, D., Charbonneau, F., Creager, M.A., Deanfield, J., Vogel, R., Guidelines for the ultrasound assessment of endothelial-dependent flow-mediated vasodilation of the brachial artery: A report of the International Brachial Artery Reactivity Task Force (2002) J Am Coll Cardiol, 39, pp. 257-265. , 11788217 10.1016/S0735-1097(01)01746-6Lang, R.M., Bierig, M., Devereux, R.B., Flachskampf, F.A., Foster, E., Pellikka, P.A., Picard, M.H., Stewart, W.J., Recommendations for chamber quantification: A report from the American Society of Echocardiography's Guidelines and Standards Committee and the Chamber Quantification Writing Group, developed in conjunction with the European Association of Echocardiography, a branch of the European Society of Cardiology (2005) J Am Soc Echocardiogr, 18, pp. 1440-1463. , 16376782 10.1016/j.echo.2005.10.005Rivas-Gotz, C., Manolios, M., Thohan, V., Nagueh, S.F., Impact of left ventricular ejection fraction on estimation of left ventricular filling pressures using tissue Doppler and flow propagation velocity (2003) Am J Cardiol, 91, pp. 780-784. , 12633827 10.1016/S0002-9149(02)03433-1Guazzi, M., Vicenzi, M., Arena, R., Guazzi, M.D., PDE5 inhibition with sildenafil improves left ventricular diastolic function, cardiac geometry, and clinical status in patients with stable systolic heart failure: Results of a 1-year, prospective, randomized, placebo-controlled study (2011) Circ Heart Fail, 4, pp. 8-17. , 1:CAS:528:DC%2BC3MXislKqt7Y%3D 21036891 10.1161/CIRCHEARTFAILURE.110. 944694Kukreja, R.C., Salloum, F., Das, A., Ockaili, R., Yin, C., Bremer, Y.A., Fisher, P.W., Xi, L., Pharmacological preconditioning with sildenafil: Basic mechanisms and clinical implications (2005) Vascul Pharmacol, 42, pp. 219-232. , 1:CAS:528:DC%2BD2MXks1ajtL0%3D 15922255 10.1016/j.vph.2005.02.010Borlaug, B.A., Melenovsky, V., Marhin, T., Fitzgerald, P., Kass, D.A., Sildenafil inhibits beta-adrenergic-stimulated cardiac contractility in humans (2005) Circulation, 112, pp. 2642-2649. , 1:CAS:528:DC%2BD2MXhtFajtLrL 16246964 10.1161/CIRCULATIONAHA.105.540500Francis, S.H., Busch, J.L., Corbin, J.D., Sibley, D., CGMP-dependent protein kinases and cGMP phosphodiesterases in nitric oxide and cGMP action (2010) Pharmacol Rev, 62, pp. 525-563. , 1:CAS:528:DC%2BC3cXhsVSltbbL 20716671 10.1124/pr.110.002907Reffelmann, T., Kloner, R.A., Cardiovascular effects of phosphodiesterase 5 inhibitors (2006) Curr Pharm des, 12, pp. 3485-3494. , 1:CAS:528:DC%2BD28XhtVGlt7%2FE 17017941 10.2174/138161206778343073Takimoto, E., Champion, H.C., Li, M., Belardi, D., Ren, S., Rodriguez, E.R., Bedja, D., Kass, D.A., Chronic inhibition of cyclic GMP phosphodiesterase 5A prevents and reverses cardiac hypertrophy (2005) Nat Med, 11, pp. 214-222. , 1:CAS:528:DC%2BD2MXpvF2nug%3D%3D 15665834 10.1038/nm1175Jiang, H., Colbran, J.L., Francis, S.H., Corbin, J.D., Direct evidence for cross-activation of cGMP-dependent protein kinase by cAMP in pig coronary arteries (1992) J Biol Chem, 267, pp. 1015-1019. , 1:CAS:528:DyaK38XotFWkuw%3D%3D 1309758Wang, H., Kohr, M.J., Traynham, C.J., Ziolo, M.T., Phosphodiesterase 5 restricts NOS3/Soluble guanylate cyclase signaling to L-type Ca2+ current in cardiac myocytes (2009) J Mol Cell Cardiol, 47, pp. 304-314. , 1:CAS:528:DC%2BD1MXnsl2it7g%3D 2703689 19345227 10.1016/j.yjmcc.2009.03. 021Calderone, A., Thaik, C.M., Takahashi, N., Chang, D.L., Colucci, W.S., Nitric oxide, atrial natriuretic peptide, and cyclic GMP inhibit the growth-promoting effects of norepinephrine in cardiac myocytes and fibroblasts (1998) J Clin Invest, 101, pp. 812-818. , 1:CAS:528:DyaK1cXht1Wrtrs%3D 508629 9466976 10.1172/JCI119883Kass, D.A., Champion, H.C., Beavo, J.A., Phosphodiesterase type 5: Expanding roles in cardiovascular regulation (2007) Circ Res, 101, pp. 1084-1095. , 1:CAS:528:DC%2BD2sXhtlahurjJ 18040025 10.1161/CIRCRESAHA.107.162511Ceyhan, C., Unal, S., Yenisey, C., Tekten, T., Ceyhan, F.B., The role of N terminal pro-brain natriuretic peptide in the evaluation of left ventricular diastolic dysfunction: Correlation with echocardiographic indexes in hypertensive patients (2008) Int J Cardiovasc Imaging, 24, pp. 253-259. , 17687631 10.1007/s10554-007-9256-2Maeda, K., Tsutamoto, T., Wada, A., Hisanaga, T., Kinoshita, M., Plasma brain natriuretic peptide as a biochemical marker of high left ventricular end-diastolic pressure in patients with symptomatic left ventricular dysfunction (1998) Am Heart J, 135, pp. 825-832. , 1:STN:280:DyaK1c3kslyhtA%3D%3D 9588412 10.1016/S0002-8703(98)70041-9Katz, D.H., Beussink, L., Sauer, A.J., Freed, B.H., Burke, M.A., Shah, S.J., Prevalence, clinical characteristics, and outcomes associated with eccentric versus concentric left ventricular hypertrophy in heart failure with preserved ejection fraction (2013) Am J Cardiol, 112, pp. 1158-1164. , 23810323 10.1016/j.amjcard.2013.05.061Paulus, W.J., Tschope, C., Sanderson, J.E., Rusconi, C., Flachskampf, F.A., Rademakers, F.E., Marino, P., Brutsaert, D.L., How to diagnose diastolic heart failure: A consensus statement on the diagnosis of heart failure with normal left ventricular ejection fraction by the Heart Failure and Echocardiography Associations of the European Society of Cardiology (2007) Eur Heart J, 28, pp. 2539-2550. , 17428822 10.1093/eurheartj/ehm037Dejam, A., Hunter, C.J., Pelletier, M.M., Hsu, L.L., Machado, R.F., Shiva, S., Power, G.G., Schechter, A.N., Erythrocytes are the major intravascular storage sites of nitrite in human blood (2005) Blood, 106, pp. 734-739. , 1:CAS:528:DC%2BD2MXmtleqtLs%3D 15774613 10.1182/blood-2005-02-0567Pelletier, M.M., Kleinbongard, P., Ringwood, L., Hito, R., Hunter, C.J., Schechter, A.N., Gladwin, M.T., Dejam, A., The measurement of blood and plasma nitrite by chemiluminescence: Pitfalls and solutions (2006) Free Radic Biol Med, 41, pp. 541-548. , 1:CAS:528:DC%2BD28XntlCqtrY%3D 16863986 10.1016/j.freeradbiomed.2006.05. 001Figueiredo, V.N., Yugar-Toledo, J.C., Martins, L.C., Martins, L.B., De Faria, A.P., De Haro, M.C., Sierra, C., Moreno, H., Vascular stiffness and endothelial dysfunction: Correlations at different levels of blood pressure (2012) Blood Press, 21, pp. 31-38. , 1:CAS:528:DC%2BC38XhtlKnsrg%3D 22029740 10.3109/08037051.2011.61704
    corecore