Postmitotic Hoxa5 Expression Specifies Pontine Neuron Positional Identity and Input Connectivity of Cortical Afferent Subsets

The mammalian precerebellar pontine nucleus (PN) has a main role in relaying cortical information to the cerebellum. The molecular determinants establishing ordered connectivity patterns between cortical afferents and precerebellar neurons are largely unknown. We show that expression of Hox5 transcription factors is induced in specific subsets of postmitotic PN neurons at migration onset. Hox5 induction is achieved by response to retinoic acid signaling, resulting in Jmjd3-dependent derepression of Polycomb chromatin and 3D conformational changes. Hoxa5 drives neurons to settle posteriorly in the PN, where they are monosynaptically targeted by cortical neuron subsets mainly carrying limb somatosensation. Furthermore, Hoxa5 postmigratory ectopic expression in PN neurons is sufficient to attract cortical somatosensory inputs regardless of position and avoid visual afferents. Transcriptome analysis further suggests that Hoxa5 is involved in circuit formation. Thus, Hoxa5 coordinates postmitotic specification, migration, settling position, and subcircuit assembly of PN neuron subsets in the cortico-cerebellar pathway.Peer reviewe

Hoxa2 Selects Barrelette Neuron Identity and Connectivity in the Mouse Somatosensory Brainstem

Mouse whiskers are somatotopically mapped in brainstem trigeminal nuclei as neuronal modules known as barrelettes. Whisker-related afferents form barrelettes in ventral principal sensory (vPrV) nucleus, whereas mandibular input targets dorsal PrV (dPrV). How barrelette neuron identity and circuitry is established is poorly understood. We found that ectopic Hoxa2 expression in dPrV neurons is sufficient to attract whisker-related afferents, induce asymmetrical dendrite arbors, and allow ectopic barrelette map formation. Moreover, the thalamic area forming whisker-related barreloids is prenatally targeted by both vPrV and dPrV axons followed by perinatal large-scale pruning of dPrV axons and refinement of vPrV barrelette input. Ectopic Hoxa2 expression allows topographically directed targeting and refinement of dPrV axons with vPrV axons into a single whisker-related barreloid map. Thus, a single HOX transcription factor is sufficient to switch dPrV into a vPrV barrelette neuron program and coordinate input-output topographic connectivity of a dermatome-specific circuit module.publishe

Postmitotic Hoxa5 Expression Specifies Pontine Neuron Positional Identity and Input Connectivity of Cortical Afferent Subsets

The mammalian precerebellar pontine nucleus (PN) has a main role in relaying cortical information to the cerebellum. The molecular determinants establishing ordered connectivity patterns between cortical afferents and precerebellar neurons are largely unknown. We show that expression of Hox5 transcription factors is induced in specific subsets of postmitotic PN neurons at migration onset. Hox5 induction is achieved by response to retinoic acid signaling, resulting in Jmjd3-dependent derepression of Polycomb chromatin and 3D conformational changes. Hoxa5 drives neurons to settle posteriorly in the PN, where they are monosynaptically targeted by cortical neuron subsets mainly carrying limb somatosensation. Furthermore, Hoxa5 postmigratory ectopic expression in PN neurons is sufficient to attract cortical somatosensory inputs regardless of position and avoid visual afferents. Transcriptome analysis further suggests that Hoxa5 is involved in circuit formation. Thus, Hoxa5 coordinates postmitotic specification, migration, settling position, and sub-circuit assembly of PN neuron subsets in the cortico-cerebellar pathway.publishe

Are hospitalized or ambulatory patients with heart failure treated in accordance with European Society of Cardiology guidelines? Evidence from 12 440 patients of the ESC Heart Failure Long-Term Registry.

AIMS: To evaluate how recommendations of European guidelines regarding pharmacological and non-pharmacological treatments for heart failure (HF) are adopted in clinical practice. METHODS AND RESULTS: The ESC-HF Long-Term Registry is a prospective, observational study conducted in 211 Cardiology Centres of 21 European and Mediterranean countries, members of the European Society of Cardiology (ESC). From May 2011 to April 2013, a total of 12 440 patients were enrolled, 40.5% with acute HF and 59.5% with chronic HF. Intravenous treatments for acute HF were heterogeneously administered, irrespective of guideline recommendations. In chronic HF, with reduced EF, renin-angiotensin system (RAS) blockers, beta-blockers, and mineralocorticoid antagonists (MRAs) were used in 92.2, 92.7, and 67.0% of patients, respectively. When reasons for non-adherence were considered, the real rate of undertreatment accounted for 3.2, 2.3, and 5.4% of the cases, respectively. About 30% of patients received the target dosage of these drugs, but a documented reason for not achieving the target dosage was reported in almost two-thirds of them. The more relevant reasons for non-implantation of a device, when clinically indicated, were related to doctor uncertainties on the indication, patient refusal, or logistical/cost issues. CONCLUSION: This pan-European registry shows that, while in patients with acute HF, a large heterogeneity of treatments exists, drug treatment of chronic HF can be considered largely adherent to recommendations of current guidelines, when the reasons for non-adherence are taken into account. Observations regarding the real possibility to adhere fully to current guidelines in daily clinical practice should be seriously considered when clinical practice guidelines have to be written