Report of the Lancet Commission on the Value of Death: bringing death back into life

The story of dying in the 21st century is a story of paradox. While many people are overtreated in hospitals with families and communities relegated to the margins, still more remain undertreated, dying of preventable conditions and without access to basic pain relief. The unbalanced and contradictory picture of death and dying is the basis for this Commission

Genomic investigations of unexplained acute hepatitis in children

Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children

Neuronal correlates of ketamine and walking induced gamma oscillations in the medial prefrontal cortex and mediodorsal thalamus

<div><p>Alterations in the function of the medial prefrontal cortex (mPFC) and its major thalamic source of innervation, the mediodorsal (MD) thalamus, have been hypothesized to contribute to the symptoms of schizophrenia. The NMDAR antagonist ketamine, used to model schizophrenia, elicits a brain state resembling early stage schizophrenia characterized by cognitive deficits and increases in cortical low gamma (40–70 Hz) power. Here we sought to determine how ketamine differentially affects spiking and gamma local field potential (LFP) activity in the rat mPFC and MD thalamus. Additionally, we investigated the ability of drugs targeting the dopamine D4 receptor (D4R) to modify the effects of ketamine on gamma activity as a measure of potential cognitive therapeutic efficacy. Rats were trained to walk on a treadmill to reduce confounds related to hyperactivity after ketamine administration (10 mg/kg s.c.) while recordings were obtained from electrodes chronically implanted in the mPFC and MD thalamus. Ketamine increased gamma LFP power in mPFC and MD thalamus in a similar frequency range, yet did not increase thalamocortical synchronization. Ketamine also increased firing rates and spike synchronization to gamma oscillations in the mPFC but decreased both measures in MD thalamus. Conversely, walking alone increased both firing rates and spike-gamma LFP correlations in both mPFC and MD thalamus. The D4R antagonist alone (L-745,870) had no effect on gamma LFP power during treadmill walking, although it reversed increases induced by the D4R agonist (A-412997) in both mPFC and MD thalamus. Neither drug altered ketamine-induced changes in gamma power or firing rates in the mPFC. However, in MD thalamus, the D4R agonist increased ketamine-induced gamma power and prevented ketamine’s inhibitory effect on firing rates. Results provide new evidence that ketamine differentially modulates spiking and gamma power in MD thalamus and mPFC, supporting a potential role for both areas in contributing to ketamine-induced schizophrenia-like symptoms.</p></div

Effects of dopamine D4R agonist and antagonist on ketamine-induced changes in spiking activity.

<p><b>A-B,</b> Average firing rates of putative mPFC pyramidal neurons (<b>A</b>) and MD thalamus neurons (<b>B</b>) at baseline (black), 15 minutes after the pretreatment injection (solid color), and 15 minutes after the subsequent additional administration of 10 mg/kg ketamine (striped). Bars in white, in red or in blue correspond to pretreatments with either saline, antagonist 5 mg/kg L-745,870 s.c., or agonist 3 mg/kg A-412997 s.c., respectively (saline: mPFC: n = 45 neurons, MD thalamus: n = 37 neurons; L-745,870: mPFC: n = 30 neurons, MD thalamus: n = 31 neurons; A-412997: mPFC: n = 38 neurons, MD thalamus: n = 31 neurons). <b>C-D,</b> Bar graphs show spike-gamma LFP correlations (filtered from 40–70 Hz) for mPFC pyramidal neurons (<b>C</b>) and MD thalamus neurons (<b>D</b>). There were no significant differences between pretreatment groups in the effect of ketamine on firing rates or spike-LFP correlations (<i>p</i> > 0.05, one-way ANOVAs). All data collected from treadmill walking epochs. Values are reported as mean ± SEM; neurons from 6 rats. *:<i>p</i> < 0.05, **:<i>p</i> < 0.01, ***:<i>p</i> < 0.001, paired bootstrap tests compare baseline walk and the drug treatments.</p

Walking-induced increases in gamma power, firing rates and spike-gamma LFP correlations.

<p><b>A,</b> Histological reconstruction showing locations (red dots) of the recording electrodes in the prelimbic mPFC and MD thalamus. <b>B,</b> Photograph shows the rotating circular treadmill. The paddle in the back ensured that the rat continued walking. <b>C,</b> Representative wavelet-based scalograms show time-frequency plots of normalized LFP spectral power during epochs with the treadmill turned ON or OFF (white bar). Warmer colors indicate higher power. <b>D,</b> Representative FFT-based spectrogram shows time-frequency coherence between the mPFC and MD thalamus. <b>E,</b> Average LFP power spectra ± SEM for epochs with treadmill ON (black) or OFF (grey) on day 1 of recording (n = 12 rats). Insets show representative traces for each structure. <b>F,</b> Bar graphs shows mean total gamma LFP power with the treadmill ON and OFF from day 1 of recording (n = 12 rats). The gamma frequency range was determined using the 15 Hz surrounding the significant gamma peak (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0186732#sec002" target="_blank">Methods</a>) between 40 and 70 Hz in each treadmill walking epoch. <b>G,</b> Representative pyramidal neuron (PYR, black) and interneuron (IN, grey) waveforms, raw signals and spike trains from the mPFC and MD thalamus during treadmill walking. <b>H</b>, Firing rates in the mPFC of PYR neurons (n = 118 neurons from 12 rats), and from MD thalamus neurons (n = 62 neurons from 12 rats). <b>I,</b> Mean ratios between peak-to-trough amplitudes of the original spike-triggered waveform average (STWA) and the mean of 20 shuffled STWAs for LFPs filtered from 40–70 Hz recorded from a neighboring wire (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0186732#sec002" target="_blank">Methods</a>). A ratio of 1 (dashed horizontal line) indicates no difference between shuffled and unshuffled values. Values are reported as mean ± SEM. *: <i>p</i> < 0.05, **: <i>p</i> < 0.01, ***: <i>p</i> < 0.001, bootstrap tests.</p

Ketamine-induced increases in gamma LFP power and spiking activity during treadmill walking.

<p><b>A,</b> Representative wavelet-based scalograms show the time-frequency plots of LFP spectral power before ketamine (<b>baseline</b>) and 13–17 minutes after 10 mg/kg ketamine s.c. (<b>Ket 15 min</b>). <b>B,</b> Representative FFT-based spectrogram shows time-frequency coherence between the mPFC and MD thalamus before ketamine and after ketamine. <b>C,</b> Averaged LFP power spectra for epochs before ketamine (black), and after ketamine (green). Insets show representative traces for each structure. <b>D,</b> Bar graph shows mean total gamma LFP power (peak ± 7 Hz) from the mPFC (n = 10 rats) and the MD thalamus (n = 6 rats) during treadmill walking at baseline (black), 15 minutes after saline injection (white), and 15 minutes (green) or 75 minutes (green with diagonal stripes) after 10 mg/kg ketamine injection. <b>E,</b> Representative examples of gamma band-pass filtered LFP (40–70 Hz) in the mPFC and MD thalamus. <b>F,</b> Representative STWAs of a mPFC pyramidal neuron (<b>D</b>) and MD thalamus neuron (<b>E</b>) with LFPs filtered from 40–70 Hz 15 minutes before and after ketamine administration. <b>G, I</b>, Mean firing rates of pyramidal neurons in the mPFC (<b>G</b>, n = 45 neurons from 6 rats) and the MD thalamus (<b>I</b>, n = 37 neurons from 6 rats). <b>H, J,</b> Bar graphs show spike-gamma LFP correlations (filtered from 40–70 Hz) for putative mPFC pyramidal neurons (<b>H</b>) and MD thalamus neurons (<b>J</b>). Values are reported as mean ± SEM. Stars over a single bar indicate this value differs significantly from the three other conditions. *: <i>p</i> < 0.05, **: <i>p</i> < 0.01, ***: <i>p</i> < 0.001, paired bootstrap tests with Bonferroni correction.</p

Time course of treatments.

<p>Time course of treatments.</p