Standardization of an isolated pig heart preparation with parabiotic circulation: methodological considerations

In the present study we standardized an experimental model of parabiotic circulation of isolated pig heart. The isolated heart was perfused with arterial blood from a second animal as support and submitted to regional ischemia for 30 min, followed by total ischemia for 90 min and reperfusion for 90 min. Parameters for measurement of ventricular performance using different indices measured directly or indirectly from intraventricular pressure were defined as: maximum peak pressure, final diastolic pressure, pressure developed, first derivative of maximum pressure (dP/dt max), first derivative of minimum pressure (dP/dt min), systolic stress of the left ventricle (sigmas), and maximum elastance of the left ventricle. Isolated hearts subjected to regional and global ischemia presented significant worsening of all measured parameters. Less discriminative parameters were dP/dt max and dP/dt min. Elastance was the most sensitive parameter during the reperfusion period, demonstrating an early loss of ventricular function during reperfusion. The model proved to be stable and reproducible and permitted the study of several variables in the isolated heart, such as ischemia and reperfusion phenomena, the effects of different drugs, surgical interventions, etc. The model introduces an advantage over the classical models which use crystalloid solutions as perfusate, because parabiotic circulation mimics heart surgery with extracorporeal circulation.64965

Toxicidade de filtrados de cultura de Alternaria euphorbiicola em folhas de Euphorbia heterophylla

A espécie fúngica Alternaria euphorbiicola é agente causal de severas necroses de inflorescência, queimas de folhas e cancros da haste em Euphorbia heterophylla (leiteiro ou amendoim-bravo), importante planta daninha responsável por grandes prejuízos à agricultura brasileira. A aplicação de suspensões de esporos do fungo sobre populações da planta hospedeira resulta em rápida produção de necrose dos tecidos das plantas (24 a 48 horas após aplicação). Essas observações levaram à conjectura de que o fungo possa produzir fitotoxinas in vitro capazes de causar lesão às plantas. O objetivo deste trabalho foi investigar preliminarmente a produção in vitro de fitotoxinas por A. euphorbiicola sob diferentes condições de cultivo. Os resultados mostraram que a composição do meio de cultura e as condições de cultivo influenciaram a fitotoxicidade de filtrados de cultura, tendo o cultivo sob agitação e na ausência de luz favorecido a produção de metabólitos fitotóxicos pelo fungo. O filtrado da cultura em meio de Jenkins-Prior modificado, crescida sob agitação, no escuro e a 28 oC, apresentou a maior atividade fitotóxica, tendo produzido extensas necroses foliares e desfolha em plantas de E. heterophylla. Esse filtrado de cultura foi submetido a extração seguida por fracionamento guiado por bioensaios. Uma fração cromatográfica constituída majoritariamente por ácidos graxos de cadeia longa produziu halos cloróticos e necrose de folhas, assim como observado após a inoculação de E. heterophylla com o fungo. Esses resultados sugerem a participação de ácidos graxos no processo infeccioso na associação A. euphorbiicola x E. heterophylla.The fungal species Alternaria euphorbiicola was identified as causal agent of inflorescence necrosis, leaf blight, and stem cancer in Euphorbia heterophylla (wild poinsettia), a major weed responsible for great agricultural losses in Brazil. The application of spore suspensions of the fungus on specimens of the host plant resulted in production of disseminated necrosis at short time intervals (24 to 48 hours) after application. These observations led to the hypothesis that the fungus could produce phytotoxins capable of causing damage to the plant. The objective of this study was to investigate the in vitro production of phytotoxins by A. euphorbiicola under different growth conditions. The results showed that the culture medium and growth conditions influenced the phytotoxicity of the culture filtrates. Growing the fungus under agitation in the dark resulted in higher production of phytotoxic metabolites. The filtrate from the culture formed in modified Jenkins-Prior medium, under agitation, at 28 oC in the dark showed the highest phytotoxic activity. This filtrate produced foliar necrosis and defoliation in E. heterophylla and was subjected to extraction followed by bioassay-guided fractionation. A chromatographic fraction consisting mainly of long-chain fatty acids produced bleached lesions and necrosis of the leaves, the same symptoms observed after inoculation of the fungus in the host plant. These results suggest the involvement of these phytotoxic fatty acids in the process of tissue invasion of E. heterophylla by A. euphorbiicola

Role Of Echocardiography In The Ventricular Assessment Of The Transplanted Heart Versus Heart Rejection

Background: Heart transplantation is an alternative for individuals with end-stage heart disease. However, episodes of heart rejection (HR) are frequent and increase morbidity and mortality, requiring the use of an accurate non-invasive exam for their diagnosis, since endomyocardial biopsy (EMB) is not a complication-free procedure. Objective: To compare the parameters obtained by use of Doppler echocardiography in a group of transplanted patients with HR (TX1) and another group of transplanted patients without rejection (TX0), having as reference a control group (CG) and observing the behavior of the left ventricular systo-diastolic function expressed as the myocardial performance index (MPI) Methods: Transthoracic echocardiographies were performed from January 2006 to January 2008 to prospectively assess 47 patients divided into three groups: CG (36.2%); TX0 (38.3%); and TX1 (25.5%). The MPI was compared between the groups, and data were analyzed by use of Fisher exact test and nonparametric Kruskal-Wallis test, both with significance level of 5%. Results: The groups did not differ regarding age, weight, height, and body surface. When compared to GC, TX0 and TX1 showed a change in the left ventricular systo-diastolic function, expressed as an increase in MPI, which was greater in TX1 [0.38 (0.29 - 0.44); 0.47 (0.43 - 0.56); 0.58 (0.52 - 0.74), respectively; p < 0.001]. Conclusion: Echocardiography was a very accurate test to detect changes in the systo-diastolic function of the transplanted heart; however, it did not prove to be reliable to replace BEM in the safe diagnosis of HR.99510311039McAlister, F.A., Ezekowitz, J.H., Hooton, N., Vandermeer, B., Spooner, C., Dryden, D.M., Cardiac resynchronization therapy for patients with left ventricular systolic dysfunction: A systematic review (2007) JAMA., 297 (22), pp. 2502-2514Sistema de Informações hospitalares do SUS. Datasus, , http://www.datasus.gov.br, Ministério da Saúde [acesso em 2009 fev 1]. Disponível emMiniati, D.N., Robbins, R.C., Reitz, B.A., Heart and heart-lung transplantation (2001) Heart disease: A textbook of cardiovascular medicine, pp. 615-634. , In: Braunwald E, Zipes DP, Libby P. 6th ed. Philadelphia: W B Saunders CompanyKostakis, A.J., White, D.J.G., Calne, R.Y., Prolongation of the rat heart allograft survival by cyclosporine A (1977) IRCS Med Sci., 5, p. 280Taylor, D.O., Edwards, L.B., Boucek, M.M., Trulock, E.P., Keck, B.M., Hertz, M.I., The registry of International Society for Heart and Lung Transplantation: Twenty-first. Official adult heart transplant report-2004 (2004) J Heart Lung Transplant., 23 (7), pp. 796-803Bocchi, E.A., Fiorelli, A.I., The Brazilian experience with heart transplantation: A multicenter report (2001) J Heart Lung Transplant., 20 (6), pp. 637-645. , The first guidelines group for heart transplantation of the Brazilian Society of CardiologyResende, M.V., Vieira, M.L., Bacal, F., Andrade, J.L., Stolf, N.A., Bocchi, E.A., Tissue doppler echocardiography in the diagnosis of heart transplantation rejection (2011) Arq Bras Cardiol., 97 (1), pp. 8-16Bacal, F., Souza-Neto, J.D., Fiorelli, A.I., Mejia, J., Marcondes-Braga, F.G., Mangini, S., II Diretriz brasileira de transplante cardíaco (2009) Arq Bras Cardiol., 94 (1 SUPL.1), pp. e16-e73. , Sociedade Brasileira de CardiologiaValantine, H.A., Schnittger, I., The role of echocardiography in the evaluation of patients after heart transplantation (2002) The practice of clinical echocardiography, pp. 658-678. , In: Otto CM. (editor). Philadelphia: W.B. Saunders CompanyLindenfeld, J., Miller, G., Shakar, S.F., Zolty, R., Lowes, B.D., Wolfel, E.E., Drug therapy in the heart transplant recipient. Part I: Cardiac rejection and immunosuppressive drugs (2004) Circulation, 110 (24), pp. 3734-3740Billingham, M.E., Cary, N.R., Hammond, M.E., Kemnitz, J., Marboe, C., McCallister, H.A., A working formulation for the standardization of nomenclature in the diagnosis of heart and lung rejection: Heart Rejection Study Group (1990) J Heart Transplant, 9 (6), pp. 587-593. , The International Society for Heart TransplantationSahn, D.J., de Maria, A., Kisslo, J., Weyman, A., Recommendations regarding quantitation in M-mode echocardiography: Results of a survey of echocardiographic measurements (1978) Circulation., 58 (6), pp. 1072-1083Schiller, N.B., Shah, P.K., Crawford, M., de Maria, A., Devereux, R., Feingenbaum, H., Recommendations for quantitation of the left ventricle by two-dimensional echocardiography (1989) J Am Soc Echocardiogr., 2 (5), pp. 358-367. , American Society of Echocardiography Committee on Standars, Subcommittee on quantitation of two-dimensional echocardiogramsLang, R.M., Bierig, M., Devereux, R.B., Flachskampf, F.A., Foster, E., Pellikkav, P.A., Recommendations for chamber quantification (2005) J Am Soc Echocardiogr., 18 (12), pp. 1440-1463. , 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 CardiologyDiretriz de angina estável (2004) Arq Bras Cardiol., 83 (SUPL. 2), pp. 6-44. , Sociedade Brasileira de CardiologiaTei, C., Ling, L.H., Hodge, D.O., Bailey, K.R., Oh, J.K., Rodeheffer, R.J., New index of combined systolic and diastolic myocardial performance: A simple and reproductible measure of cardiac function-a study in normal and dilated cardiomyopathy (1995) J Cardiol., 26 (6), pp. 357-366Gulati, V.K., Katz, W.E., Follansbee, W.P., Gorcsan III, J., Mitral annular decent velocity by tissue Doppler echocardiography as an index of global left ventricular function (1996) Am J Cardiol., 77 (11), pp. 979-984Oki, T., Tabata, T., Yamada, H., Clinical application of pulsed Doppler tissue imaging for assessing abnormal left ventricular relaxation (1997) Am J Cardiol., 79 (7), pp. 921-928Srivastava, P.M., Burell, L.M., Calafiore, P., Lateral vs medial mitral annular tissue Doppler in the echocardiographic assessment of diastolic function and filling pressures: Which should we use? 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Measurement of the Bs0→J/ψKS0B_s^0\to J/\psi K_S^0 branching fraction

The $B_s^0\to J/\psi K_S^0$ branching fraction is measured in a data sample corresponding to 0.41$fb^{-1}$ of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to the penguin contributions affecting the sin2$\beta$ measurement from $B^0\to J/\psi K_S^0$ The time-integrated branching fraction is measured to be $BF(B_s^0\to J/\psi K_S^0)=(1.83\pm0.28)\times10^{-5}$. This is the most precise measurement to date

Model-independent search for CP violation in D0→K−K+π−π+ and D0→π−π+π+π− decays

A search for CP violation in the phase-space structures of D0 and View the MathML source decays to the final states K−K+π−π+ and π−π+π+π− is presented. The search is carried out with a data set corresponding to an integrated luminosity of 1.0 fb−1 collected in 2011 by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. For the K−K+π−π+ final state, the four-body phase space is divided into 32 bins, each bin with approximately 1800 decays. The p-value under the hypothesis of no CP violation is 9.1%, and in no bin is a CP asymmetry greater than 6.5% observed. The phase space of the π−π+π+π− final state is partitioned into 128 bins, each bin with approximately 2500 decays. The p-value under the hypothesis of no CP violation is 41%, and in no bin is a CP asymmetry greater than 5.5% observed. All results are consistent with the hypothesis of no CP violation at the current sensitivity

Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays

Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found.Comment: 15 pages, 10 figures; minor revisions on May 23, 201