Proper layering is important for precisely timed activation of hippocampal mossy cells.

The mammalian cortex exhibits a laminated structure that may underlie optimal synaptic connectivity and support temporally precise activation of neurons. In 'reeler' mice, the lack of the extracellular matrix protein Reelin leads to abnormal positioning of cortical neurons and disrupted layering. To address how these structural changes impact neuronal function, we combined electrophysiological and neuroanatomical techniques to investigate the synaptic activation of hippocampal mossy cells (MCs), the cell type that integrates the output of dentate gyrus granule cells (GCs). While somatodendritic domains of wild-type (WT) MCs were confined to the hilus, the somata and dendrites of reeler MCs were often found in the molecular layer, where the perforant path (PP) terminates. Most reeler MCs received aberrant monosynaptic excitatory input from the PP, whereas the disynaptic input to MCs via GCs was decreased and inhibition was increased. In contrast to the uniform disynaptic discharge of WT MCs, many reeler cells discharged with short, monosynaptic latencies, while others fired with long latencies over a broad temporal window in response to PP activation. Thus, disturbed lamination results in aberrant synaptic connectivity and altered timing of action potential generation. These results highlight the importance of a layered cortical structure for information processing.

[German recommendations on lung and thoracic ultrasonography in patients with COVID-19]. / Empfehlungen zur Lungen- und Thoraxsonographie bei Patienten mit COVID-19-Erkrankung.

Lung and chest ultrasound are further examination modalities in addition to computed tomography and laboratory diagnostics in patients with COVID-19. It extends the clinical-physical examination because it can examine lung surface sensitively. Lung surface pattern changes have been found in sonograms of patients with COVID-19 pneumonia and during the course of the disease. German specialist societies of clinical acute, emergency and intensive care medicine as well as imaging, which are concerned with the care of patients with SARS-CoV­2 infection and COVID-19, have coordinated recommendations for lung and thorax sonography. This document has been created within a transparent process, led by the German Society of Interdisciplinary Emergency and Acute Medicine e. V. (DGINA), and worked out by an expert panel and delegates from the societies. Sources of the first 200 cases were summarized. Typical thorax sonographic findings are presented. International sources or standards that were available in PubMed until May 24, 2020 were included. Using case studies and multimedia content, the document is intended to not only support users but also demonstrate quality features and the potential of chest and lung sonography. The German Society for Ultrasound in Medicine (DEGUM) is carrying out a multicenter study (study coordination at the TU Munich).