Lung ultrasound-guided therapy reduces acute decompensation events in chronic heart failure.

OBJECTIVE: Pulmonary congestion is the main cause of hospital admission in patients with heart failure (HF). Lung ultrasound (LUS) is a useful tool to identify subclinical pulmonary congestion. We evaluated the usefulness of LUS in addition to physical examination (PE) in the management of outpatients with HF. METHODS: In this randomised multicentre unblinded study, patients with chronic HF and optimised medical therapy were randomised in two groups: 'PE+LUS' group undergoing PE and LUS and 'PE only' group. Diuretic therapy was modified according to LUS findings and PE, respectively. The primary endpoint was the reduction in hospitalisation rate for acute decompensated heart failure (ADHF) at 90-day follow-up. Secondary endpoints were reduction in NT-proBNP, quality-of-life test (QLT) and cardiac mortality at 90-day follow-up. RESULTS: A total of 244 patients with chronic HF and optimised medical therapy were enrolled and randomised in 'PE+LUS' group undergoing PE and LUS, and in 'PE only' group. Thirty-seven primary outcome events occurred. The hospitalisation for ADHF at 90 day was significantly reduced in 'PE+LUS' group (9.4% vs 21.4% in 'PE only' group; relative risk=0.44; 95% CI 0.23 to 0.84; p=0.01), with a reduction of risk for hospitalisation for ADHF by 56% (p=0.01) and a number needed to treat of 8.4 patients (95% CI 4.8 to 34.3). At day 90, NT-proBNP and QLT score were significantly reduced in 'PE+LUS' group, whereas in 'PE only' group both were increased. There were no differences in mortality between the two groups. CONCLUSIONS: LUS-guided management reduces hospitalisation for ADHF at mid-term follow-up in outpatients with chronic HF.

Activity-dependent rapid local RhoA synthesis is required for hippocampal synaptic plasticity.

Dendritic protein synthesis and actin cytoskeleton reorganization are important events required for the consolidation of hippocampal LTP and memory. However, the temporal and spatial relationships between these two processes remain unclear. Here, we report that treatment of adult rat hippocampal slices with BDNF or with tetraethylammonium (TEA), which induces a chemical form of LTP, produces a rapid and transient increase in RhoA protein levels. Changes in RhoA were restricted to dendritic spines of CA3 and CA1 and require de novo protein synthesis regulated by mammalian target of rapamycin (mTOR). BDNF-mediated stimulation of RhoA activity, cofilin phosphorylation, and actin polymerization were completely suppressed by protein synthesis inhibitors. Furthermore, intrahippocampal injections of RhoA antisense oligodeoxynucleotides inhibited theta burst stimulation (TBS)-induced RhoA upregulation in dendritic spines and prevented LTP consolidation. Addition of calpain inhibitors after BDNF or TEA treatment maintained RhoA levels elevated and prolonged the effects of BDNF and TEA on actin polymerization. Finally, the use of isoform-selective calpain inhibitors revealed that calpain-2 was involved in RhoA synthesis, whereas calpain-1 mediated RhoA degradation. Overall, this mechanism provides a novel link between dendritic protein synthesis and reorganization of the actin cytoskeleton in hippocampal dendritic spines during LTP consolidation.

SAP97 blocks the RXR ER retention signal of NMDA receptor subunit GluN1-3 through its SH3 domain.

SAP97 is directly involved in exporting NMDA receptors with a specific subunit composition from the endoplasmic reticulum (ER). Characterization of the interactions between SAP97 and an NMDA receptor splice variant, GluN1-3, and of the effects on forward trafficking revealed that an ER-level interaction blocked the RXR ER-retention motif in the GluN1-3 cytoplasmic C-terminus in the context of both reporter molecules and full-length receptors. Binding of SAP97 to the PDZ-binding domain of GluN1-3 was required, but the blockade of ER-retention was mediated by the SH3-GuK domains coupled with the action of the N-terminus of SAP97. While other domains of SAP97 were involved in forward trafficking of GluN1-3 out of the ER, the SH3 domain was necessary and sufficient to block the ER retention. This is the first direct evidence for the masking of ER-retention signals by PDZ domain-containing proteins, and provides detailed underlying mechanistic requirements. Such a mechanism could be central to modulating the ER exit of receptors into local, non-conventional or conventional, secretory pathways in neurons.