Public Opinion on Peace as a Reflection of Social Differentiation and Politicisation of Identity in Sri Lanka

This article provides a critical analysis of the public opinion on peace in Sri Lanka, with consideration to two determinants: social differentiation and politicisation of identities. Specifically, it aims at developing arguments about the correlations between public opinion, social position, and political mobilisation. Inspired by Bourdieu\u27s concepts of habitus, social space, and political field, this article develops an empirical analysis of the links between ethnic identity and public opinion on peace, and between social differentiation and opinions within the Sinhalese majority community in Sri Lanka. This article argues that ethnic polarisation and politicisation were the foremost determinants of public opinion during the peace process in 2002-2009

Secretoneurin Is an Endogenous Calcium/Calmodulin-Dependent Protein Kinase II Inhibitor That Attenuates Ca2+-Dependent Arrhythmia

BACKGROUND: Circulating SN (secretoneurin) concentrations are increased in patients with myocardial dysfunction and predict poor outcome. Because SN inhibits CaMKII delta (Ca2+/calmodulin-dependent protein kinase II delta) activity, we hypothesized that upregulation of SN in patients protects against cardiomyocyte mechanisms of arrhythmia. METHODS: Circulating levels of SN and other biomarkers were assessed in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT; n=8) and in resuscitated patients after ventricular arrhythmia-induced cardiac arrest (n=155). In vivo effects of SN were investigated in CPVT mice (RyR2 [ryanodine receptor 2]-R2474S) using adeno-associated virus-9-induced overexpression. Interactions between SN and CaMKII delta were mapped using pull-down experiments, mutagenesis, ELISA, and structural homology modeling. Ex vivo actions were tested in Langendorff hearts and effects on Ca2+ homeostasis examined by fluorescence (fluo-4) and patchclamp recordings in isolated cardiomyocytes. RESULTS: SN levels were elevated in patients with CPVT and following ventricular arrhythmia-induced cardiac arrest. In contrast to NT-proBNP (N-terminal proB- type natriuretic peptide) and hs-TnT (high-sensitivity troponin T), circulating SN levels declined after resuscitation, as the risk of a new arrhythmia waned. Myocardial pro-SN expression was also increased in CPVT mice, and further adeno-associated virus-9-induced overexpression of SN attenuated arrhythmic induction during stress testing with isoproterenol. Mechanistic studies mapped SN binding to the substrate binding site in the catalytic region of CaMKII delta. Accordingly, SN attenuated isoproterenol induced autophosphorylation of Thr287-CaMKII delta in Langendorff hearts and inhibited CaMKII delta-dependent RyR phosphorylation. In line with CaMKII delta and RyR inhibition, SN treatment decreased Ca2+ spark frequency and dimensions in cardiomyocytes during isoproterenol challenge, and reduced the incidence of Ca2+ waves, delayed afterdepolarizations, and spontaneous action potentials. SN treatment also lowered the incidence of early afterdepolarizations during isoproterenol; an effect paralleled by reduced magnitude of L-type Ca2+ current. CONCLUSIONS: SN production is upregulated in conditions with cardiomyocyte Ca2+ dysregulation and offers compensatory protection against cardiomyocyte mechanisms of arrhythmia, which may underlie its putative use as a biomarker in at-risk patients.Peer reviewe