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Purpose of ReviewHuman T-cell lymphotropic virus type 1 (HTLV-1)–associated myelopathy (HAM) is a well-recognized neurologic complication of HTLV-1. Beyond HAM, several other neurologic manifestations are increasingly recognized, including acute myelopathy, encephalopathy, and myositis. The clinical and imaging features of these presentations are less well understood and potentially underdiagnosed. In this study, we summarize the imaging features of HTLV-1–related neurologic disease, providing both a pictorial review and pooled series of the less well-recognized presentations.Recent Findings35 cases of acute/subacute HAM and 12 cases of HTLV-1–related encephalopathy were found. In subacute HAM, cervical and upper thoracic longitudinally extensive tranverse myelitis was noted, while in HTLV-1–related encephalopathy, confluent lesions in the frontoparietal white matter and along the corticospinal tracts were the most prevalent finding.SummaryThere are varied clinical and imaging presentations of HTLV-1–related neurologic disease. Recognition of these features aids early diagnosis where therapy may have the greatest benefit.

Background: The spring COVID-19 pandemic surge overwhelmed New York City (NYC) hospitals, requiring pediatric providers to care for adults with COVID-19. Health care workers (HCW) experienced high levels of stress and trauma, raising concern for mental health impacts. This study aimed to determine the rate at which HCW reported post-traumatic stress symptoms (PTSS) and if social determinants of health (SDoH), COVID-19-associated stressors at home, and engagement in self-care behaviors were associated with PTSS. Methods: A cross-sectional anonymous survey study was conducted at a large tertiary care pediatric hospital in NYC five months after the initial COVID-19 surge to detect prevalence of PTSS. Secondary outcomes were adverse SDoH, COVID-related stressors, and self-care behaviors. Bivariate analyses and logistic regression were performed to examine whether secondary outcomes and confounders were associated with PTSS. Outcomes: 193 HCW completed the study. The overall prevalence of PTSS was 20·2 %. Rates were higher in non-independent providers (30·6%) than independent providers (physicians, PAs, NPs; 2·7%). PTSS rates were also higher in non-white HCW and in those with dependents, > 2 adverse SDoH, high COVID-19 stressors, and low self-care in bivariate analyses. Odds of PTSS were significantly higher in non-independent providers (aOR=15·4), those who screened positive for > 2 adverse SDoH (aOR=4·0), and those with higher COVID-19 stressors (aOR=12·3). Interpretation: One in five pediatric HCW experienced PTSS five months after the COVID-19 spring surge in NYC. Interventions to connect HCW with mental health and wellness resources are critical as surges continue nationwide. Funding: N/A Declaration of Interests: None to declare. Ethics Approval Statement: The study was approved by the Institutional Review Board.

Adaptation to the ever-changing world is critical for survival, and our brains are particularly tuned to remember events that differ from previous experiences. Novel experiences induce dopamine release in the hippocampus, a process which promotes memory persistence. While axons from the ventral tegmental area (VTA) were generally thought to be the exclusive source of hippocampal dopamine, recent studies have demonstrated that noradrenergic neurons in the locus coeruleus (LC) corelease noradrenaline and dopamine in the hippocampus and that their dopamine release boosts memory retention as well. In this opinion article, we propose that the projections originating from the VTA and the LC belong to two distinct systems that enhance memory of novel events. Novel experiences that share some commonality with past ones (‘common novelty’) activate the VTA and promote semantic memory formation via systems memory consolidation. By contrast, experiences that bear only a minimal relationship to past experiences (‘distinct novelty’) activate the LC to trigger strong initial memory consolidation in the hippocampus, resulting in vivid and long-lasting episodic memories., Highlights Novelty induces dopamine release in the hippocampus, triggering memory consolidation to boost memory persistence. Two dopaminergic systems (the ventral tegmental area- and locus coeruleus-hippocampus systems) can stabilise memory through novelty-induced dopamine release in the hippocampus. Novel experiences can be viewed as a spectrum, from experiences that, while clearly novel, share some commonality with past experiences (‘common novelty’), to more fundamentally distinct experiences that bear minimal relationships to past experiences (‘distinct novelty’). We propose that events characterised by ‘common novelty’ boost memory retention via activation of the ventral tegmental area-hippocampus system, resulting in initial consolidation followed by systems consolidation to create neocortical, semantic, long-term memories. We further propose that events characterised by ‘distinct novelty’ lead to the boost of detailed hippocampal, episodic, long-term memory via activation of the locus coeruleus-hippocampus system through strong upregulation of the synaptic tagging and capture mechanism.

Central to the understanding of memory is a detailed understanding of the processes contributing to how some information is retained as memories, yet other information is not. Relevant to this is the question, does value and saliency information coded by dopaminergic neurons of the ventral tegmental area (VTA) affect hippocampal memory function and how might this arise? In order to address this question, I performed large scale extracellular recordings combined with optogenetic activation of dopaminergic neurons in mice. Tetrodes were located in the VTA and pyramidal cell layer of the CA1 subfield of the dorsal hippocampus. Midbrain dopaminergic neurons were made to express a chimeric protein formed of the light activated ion channel channelrhodopsin-2 and enhanced yellow florescent protein (ChR2-eYFP) through injection of a Cre activated viral construct in the VTA of DAT-IRES-Cre+/- mice. Mice explored familiar and novel open fields in the presence or absence of photostimulation. Periods of sleep and rest were recorded before and after each exploration in order to calculate the reactivation strength of hippocampal waking firing activity during subsequent sleep; a process thought to aid the stabilisation of representations enhancing their retention as memories. ChR2-eYFP expressing axons were present in the dorsal hippocampus demonstrating a direct dopaminergic projection from the midbrain to the hippocampus. Units isolated from midbrain tetrodes showed a sustained increase in mean firing rate during exploration of a novel over a familiar environment, indicating they have the potential to drive sustained dopamine release in target structures in response to such a sustained novelty cue. Hippocampal reactivation strength after exploration of a novel environment was higher than that seen after exploration of a familiar environment and this was further enhanced by burst mode photoactivation of dopaminergic neurons at their cell bodies in the VTA or at the afferent dopaminergic fibres in the dorsal CA1. A second group of mice performed a spatial learning task on a maze dubbed the 'crossword maze'. Photostimulation during learning trials did not increase the rate of learning but it did increase performance in a probe test held one hour after the end of the learning trials. Additionally, there was enhanced reinstatement of the hippocampal spatial representation during the probe test and it was preceded by enhanced reactivation of the newly formed representation in the intervening rest period. These findings reveal that midbrain dopaminergic neurons, encoding salient information about an environment, promote hippocampal network dynamics associated with memory persistence, thus modulating hippocampal memory function according to the value of the information to be remembered.

Neurological complications of haematological malignancies are wide ranging but isolated myopathy as a presenting complaint is rare.Cases: 63 year-old lady with progressive proximal upper then lower limb weakness over 7 years to wheelchair-dependence and hoist-transfers. Muscle biopsy revealed nemalin rods, HIV negative, IgG kappa paraprotein=6 g/L. Late-onset nemalin rod myopathy was diagnosed; function is stable 6/12 post-autologous bone marrow transplant.56 year-old lady with limb-girdle weakness leading to immobility over 2 years and IgG lambda MGUS. Re-examination of muscle biopsy revealed amyloid deposition, SAP scan negative for systemic AL amyloid. Treated with velcade and dexamethasone but died from amyloid cardiomyopathy 6/12 later.73 year-old man with painless deltoid weakness. Muscle biopsy revealed plasma cells infiltrate and lightchain deposition with matched lightchain restriction in bone marrow, IgG kappa paraprotein=8 g/L. Cyclosporin and dexamethasone were recommended for infiltrative multifocal, myopathic plasmacytoma.28 year-old female with pain, fatigue and pelvic-girdle weakness was diagnosed with haemophagocytic lymphohistiocytosis without systemic lymphoma or connective tissue disease. Muscle biopsy demonstrated T-cell and macrophage infiltration. Muscle symptoms are responding to steroids, mycophenolate, cyclosporine and etopiside. An allogenic bone marrow transplant is planned.We describe four cases of progressive myopathic weakness as the primary manifestation of an underlying haematological disorder.