Near-field enhancement in oxidized close gap aluminum dimers.

Aluminum bowtie nanoantennas represent a possibility to confine and enhance electromagnetic (EM) field at optical frequencies in subwavelength regions by using an abundant and inexpensive metal. The native oxidation process of this metal is often viewed as a limitation for its application in plasmonics. Here, we show that in close gap configurations, the high refractive index of the native aluminum oxide helps in squeezing the plasmonic mode in extremely reduced size volumes, providing a higher EM near-field confinement and enhancement in the bowtie antenna gaps than achieved in the pure aluminum counterpart. Hence, the study provides new perspectives in the use of such a plasmonic antenna geometry within this aluminum system, which can be useful for improving plasmonics-enabled effects such as surface-enhanced Raman scattering- and light-matter interaction in strong coupling regime.

Cardiac Magnetic Resonance in Primary Prevention of Sudden Cardiac Death.

Sudden death accounts for 400,000 deaths annually in the United States. Most sudden deaths are cardiac and are related to arrhythmias secondary to structural heart disease or primary electrical abnormalities of the heart. Implantable cardioverter defibrillator significantly improves survival in patients at increased risk of life-threatening arrhythmias, but better selection of eligible patients is required to avoid unnecessary implantation and identify those patients who may benefit most from this therapy. Left ventricular (LV) ejection fraction (EF) measured by echocardiography has been considered the most reliable parameter for long-term outcome in many cardiac diseases. However, LVEF is an inaccurate parameter for arrhythmic risk assessment as patients with normal or mildly reduced LV systolic function could experience sudden cardiac death (SCD). Among other tools for arrhythmic stratification, magnetic resonance (CMR) provides the most comprehensive cardiac evaluation including in vivo tissue characterization and significantly aids in the identification of patients at higher SCD risk. Most of the evidence are related to late gadolinium enhancement (LGE), which was proven to detect cardiac fibrosis. LGE has been reported to add incremental value for prognostic stratification and SCD prediction across a wide range of cardiac diseases, including both ischemic and nonischemic cardiomyopathies. In addition, T1, T2 mapping and extracellular volume assessment were reported to add incremental value for arrhythmic assessment despite suffering from several technical limitations. CMR should be part of a multiparametric approach for patients' evaluation, and it will play a pivotal role in prognostic stratification according to the current evidence.

Cdk9, a member of the cdc2-like family of kinases, binds to gp130, the receptor of the IL-6 family of cytokines.

Cdk9 is a member of the Cdc2-like family of kinases. It binds to members of the family of cyclin T (T1, T2a and T2b) and to cyclin K. The Cdk9/cyclin T complex appears to be involved in regulating several physiological processes. In fact Cdk9 is the kinase of the P-TEFb complex, involved in basal transcription. Cdk9 has also been described as the kinase of the TAK complex, homologous to P-TEFb and involved in HIV replication. Here we show that Cdk9 interacts with gp130, the receptor of the Interleukin-6 (IL-6) family of cytokines, which includes Leukemia Inhibitory Factor (LIF), Oncostatin M (OSM), Ciliary Neurotrophic Factor (CNTF), Interleukin-11 (IL-11) and Cardiotrophin (CT-1). IL-6 is a key regulator of hematopoiesis, immunological responses and inflammation. In addition, IL-6 plays a major role in the endocrine and nervous systems. Signal transduction by gp130 is mediated by physical interaction of the cytoplasmic region of gp130 with cellular kinases and results in the transcriptional activation of cellular and viral genes. We found that Cdk9 interacts in vitro with the cytoplasmic region of gp130 and we succeded in reproducing this interaction in vivo. Cdk9 expression was found both in the nucleus and in the cytoplasm. The binding occurring between Cdk9 and gp130 increased upon IL-6 stimulation. We also observed that Cdk9 synergized with IL-6 in inducing the activation of an IL-6-responsive reporter plasmid. In summary, these results point to a previously undisclosed role for Cdk9 in signal transduction.