Nausea-induced suppression of feeding is mediated by central amygdala Dlk1-expressing neurons

The motivation to eat is suppressed by satiety and aversive stimuli such as nausea. The neural circuit mechanisms of appetite suppression by nausea are not well understood. Pkcδ neurons in the lateral subdivision of the central amygdala (CeA) suppress feeding in response to satiety signals and nausea. Here, we characterized neurons enriched in the medial subdivision (CeM) of the CeA marked by expression of Dlk1. CeADlk1 neurons are activated by nausea, but not satiety, and specifically suppress feeding induced by nausea. Artificial activation of CeADlk1 neurons suppresses drinking and social interactions, suggesting a broader function in attenuating motivational behavior. CeADlk1 neurons form projections to many brain regions and exert their anorexigenic activity by inhibition of neurons of the parabrachial nucleus. CeADlk1 neurons are inhibited by appetitive CeA neurons, but also receive long-range monosynaptic inputs from multiple brain regions. Our results illustrate a CeA circuit that regulates nausea-induced feeding suppression.

[Work and Employment Situation of People with Mental Illness Receiving Independent Supported Housing: An Analysis of Routine Data from a Community Psychiatry Service]

OBJECTIVES

Due to insufficient empirical data on the occupational participation of people affected by severe mental illness receiving integration assistance, routine data from a community psychiatry service were evaluated.

METHODS

Reference workers filled out a short questionnaire on different occupational and employment aspects of their clients from supported housing/floating outreach. In addition to descriptive and exploratory analyses, overall results from previous survey rounds were also evaluated.

RESULTS

N=1418 individuals (M=47.6 years) could be included, of whom approximately 45% had no job, sheltered employment, or daytime service. This percentage has remained almost unchanged over the last decades.

CONCLUSION

Overall, there is an urgent need for action to improve occupational participation opportunities for people with mental illness and substance addiction.

Neuroprotective effects of hepatoma-derived growth factor in models of Huntington's disease

Huntington's disease (HD) is a movement disorder caused by a mutation in the Huntingtin gene that leads to severe neurodegeneration. Molecular mechanisms of HD are not sufficiently understood, and no cure is currently available. Here, we demonstrate neuroprotective effects of hepatoma-derived growth factor (HDGF) in cellular and mouse HD models. We show that HD-vulnerable neurons in the striatum and cortex express lower levels of HDGF than resistant ones. Moreover, lack of endogenous HDGF exacerbated motor impairments and reduced the life span of R6/2 Huntington's disease mice. AAV-mediated delivery of HDGF into the brain reduced mutant Huntingtin inclusion load, but had no significant effect on motor behavior or life span. Interestingly, both nuclear and cytoplasmic versions of HDGF were efficient in rescuing mutant Huntingtin toxicity in cellular HD models. Moreover, extracellular application of recombinant HDGF improved viability of mutant Huntingtin-expressing primary neurons and reduced mutant Huntingtin aggregation in neural progenitor cells differentiated from human patient-derived induced pluripotent stem cells. Our findings provide new insights into the pathomechanisms of HD and demonstrate neuroprotective potential of HDGF in neurodegeneration.

Postnatal surgical treatment and complications following intrauterine vesicoamniotic shunting with the SOMATEX® intrauterine shunt. A single center experience

INTRODUCTION

Intrauterine vesicoamniotic shunting (VAS) using a Somatex® shunt was shown to significantly affect survival of male fetuses with megacystis in suspected lower urinary tract obstruction (LUTO) [Figure 1]. Data on postnatal surgical management and complications are largely lacking.

OBJECTIVE

To describe the postnatal management of patients with prenatal VAS for megacystitis in suspected severe LUTO.

STUDY DESIGN

All male newborns with previous intrauterine VAS using a Somatex® shunt treated in our institution were retrospectively analyzed. We evaluated the spectrum of urethral pathologies and postnatal surgical management, especially focusing on shunt removal.

RESULTS

Between 2016 and 2022, 17 patients (all male) were treated postnatally in our institution after VAS for suspected severe LUTO. Five fetuses with dislocated shunts underwent re-implantation in utero. Overall, premature birth before the 38th week of gestation was observed in eight patients (8/17). Seven shunts could be removed without further anesthesia as a bedside procedure. Ten patients required surgical shunt removal under general anesthesia due to migration (59%). Laparoscopic shunt extraction was performed in 8/10 cases. Most frequently, dislocated shunts were located incorporated in the detrusor in eight cases and the removal required a bladder suture in 2/8 patients. In one case, the shunt was removed from the abdominal wall and in one case from the intestine wall [Figure 2]. Posterior urethral valves were found in 8/17 patients, 6/17 patients showed a urethral atresia and one patient had urethral duplication. In two patients, we identified a high grade bilateral vesicoureteral reflux without LUTO.

CONCLUSION

In our observation, more than half of the newborns with megacystis in suspected LUTO require a shunt removal surgery after early VAS using a Somatex® shunt. Urethral atresia may be found more frequently in these patients. These data should be taken into consideration for prenatal counselling of parents and planning of postnatal management.

Transcriptomics reveals amygdala neuron regulation by fasting and ghrelin thereby promoting feeding

The central amygdala (CeA) consists of numerous genetically defined inhibitory neurons that control defensive and appetitive behaviors including feeding. Transcriptomic signatures of cell types and their links to function remain poorly understood. Using single-nucleus RNA sequencing, we describe nine CeA cell clusters, of which four are mostly associated with appetitive and two with aversive behaviors. To analyze the activation mechanism of appetitive CeA neurons, we characterized serotonin receptor 2a (Htr2a)-expressing neurons (CeA^Htr2a) that comprise three appetitive clusters and were previously shown to promote feeding. In vivo calcium imaging revealed that CeA^Htr2a neurons are activated by fasting, the hormone ghrelin, and the presence of food. Moreover, these neurons are required for the orexigenic effects of ghrelin. Appetitive CeA neurons responsive to fasting and ghrelin project to the parabrachial nucleus (PBN) causing inhibition of target PBN neurons. These results illustrate how the transcriptomic diversification of CeA neurons relates to fasting and hormone-regulated feeding behavior.

Tripartite extended amygdala-basal ganglia CRH circuit drives locomotor activation and avoidance behavior

An adaptive stress response involves various mediators and circuits orchestrating a complex interplay of physiological, emotional, and behavioral adjustments. We identified a population of corticotropin-releasing hormone (CRH) neurons in the lateral part of the interstitial nucleus of the anterior commissure (IPACL), a subdivision of the extended amygdala, which exclusively innervate the substantia nigra (SN). Specific stimulation of this circuit elicits hyperactivation of the hypothalamic-pituitary-adrenal axis, locomotor activation, and avoidance behavior contingent on CRH receptor type 1 (CRHR1) located at axon terminals in the SN, which originate from external globus pallidus (GPe) neurons. The neuronal activity prompting the observed behavior is shaped by IPACL^CRH and GPe^CRHR1 neurons coalescing in the SN. These results delineate a previously unidentified tripartite CRH circuit functionally connecting extended amygdala and basal ganglia nuclei to drive locomotor activation and avoidance behavior.

Distinct histological alterations of cortical interneuron types in mouse models of Huntington’s disease

Huntington’s disease (HD) is a debilitating hereditary motor disorder caused by an expansion of the CAG triplet repeat in the Huntingtin gene. HD causes neurodegeneration particularly in the basal ganglia and neocortex. In the cortex, glutamatergic pyramidal neurons are known to be severely affected by the disease, but the involvement of GABAergic interneurons remains unclear. Here, we use a combination of immunostaining and genetic tracing to investigate histological changes in three major cortical interneuron types — parvalbumin (PV), somatostatin (SST), and vasoactive intestinal peptide (VIP) interneurons — in the R6/2 and zQ175DN mouse models of HD. In R6/2 mice, we find a selective reduction in SST and VIP, but not PV-positive cells. However, genetic labeling reveals unchanged cell numbers for all the interneuron types, pointing to molecular marker loss in the absence of cell death. We also observe a reduction in cell body size for all three interneuron populations. Furthermore, we demonstrate progressive accumulation of mutant Huntingtin (mHTT) inclusion bodies in interneurons, which occurs faster in SST and VIP compared to PV cells. In contrast to the R6/2 model, heterozygous zQ175DN knock-in HD mice do not show any significant histological changes in cortical cell types at the age of 12 months, apart from the presence of mHTT inclusions, which are abundant in pyramidal neurons and rare in interneurons. Taken together, our findings point to differential molecular changes in cortical interneuron types of HD mice.

FLRT3 Marks Direction-Selective Retinal Ganglion Cells That Project to the Medial Terminal Nucleus

The mammalian retina extracts a multitude of diverse features from the visual scene such as color, contrast, and direction of motion. These features are transmitted separately to the brain by more than 40 different retinal ganglion cell (RGC) subtypes. However, so far only a few genetic markers exist to fully characterize the different RGC subtypes. Here, we present a novel genetic Flrt3-CreERT2 knock-in mouse that labels a small subpopulation of RGCs. Using single-cell injection of fluorescent dyes in Flrt3 positive RGCs, we distinguished four morphological RGC subtypes. Anterograde tracings using a fluorescent Cre-dependent Adeno-associated virus (AAV) revealed that a subgroup of Flrt3 positive RGCs specifically project to the medial terminal nucleus (MTN), which is part of the accessory optic system (AOS) and is essential in driving reflex eye movements for retinal image stabilization. Functional characterization using ex vivo patch-clamp recordings showed that the MTN-projecting Flrt3 RGCs preferentially respond to downward motion in an ON-fashion. These neurons distribute in a regular pattern and most of them are bistratified at the level of the ON and OFF bands of cholinergic starburst amacrine cells where they express the known ON-OFF direction-selective RGC marker CART. Together, our results indicate that MTN-projecting Flrt3 RGCs represent a new functionally homogeneous AOS projecting direction-selective RGC subpopulation.

Amyloid-like aggregating proteins cause lysosomal defects in neurons via gain-of-function toxicity

Using cryo-ET, cell biology, and proteomics, this study shows that aggregating proteins impair the autophagy-lysosomal pathway in neurons by sequestering a subunit of the AP-3 adaptor complex.

The autophagy-lysosomal pathway is impaired in many neurodegenerative diseases characterized by protein aggregation, but the link between aggregation and lysosomal dysfunction remains poorly understood. Here, we combine cryo-electron tomography, proteomics, and cell biology studies to investigate the effects of protein aggregates in primary neurons. We use artificial amyloid-like β-sheet proteins (β proteins) to focus on the gain-of-function aspect of aggregation. These proteins form fibrillar aggregates and cause neurotoxicity. We show that late stages of autophagy are impaired by the aggregates, resulting in lysosomal alterations reminiscent of lysosomal storage disorders. Mechanistically, β proteins interact with and sequester AP-3 μ1, a subunit of the AP-3 adaptor complex involved in protein trafficking to lysosomal organelles. This leads to destabilization of the AP-3 complex, missorting of AP-3 cargo, and lysosomal defects. Restoring AP-3μ1 expression ameliorates neurotoxicity caused by β proteins. Altogether, our results highlight the link between protein aggregation, lysosomal impairments, and neurotoxicity.

Fluc-EGFP reporter mice reveal differential alterations of neuronal proteostasis in aging and disease

The cellular protein quality control machinery is important for preventing protein misfolding and aggregation. Declining protein homeostasis (proteostasis) is believed to play a crucial role in age‐related neurodegenerative disorders. However, how neuronal proteostasis capacity changes in different diseases is not yet sufficiently understood, and progress in this area has been hampered by the lack of tools to monitor proteostasis in mammalian models. Here, we have developed reporter mice for in vivo analysis of neuronal proteostasis. The mice express EGFP‐fused firefly luciferase (Fluc‐EGFP), a conformationally unstable protein that requires chaperones for proper folding, and that reacts to proteotoxic stress by formation of intracellular Fluc‐EGFP foci and by reduced luciferase activity. Using these mice, we provide evidence for proteostasis decline in the aging brain. Moreover, we find a marked reaction of the Fluc‐EGFP sensor in a mouse model of tauopathy, but not in mouse models of Huntington’s disease. Mechanistic investigations in primary neuronal cultures demonstrate that different types of protein aggregates have distinct effects on the cellular protein quality control. Thus, Fluc‐EGFP reporter mice enable new insights into proteostasis alterations in different diseases.

A retrospective case-control cohort analysis of comorbidity and health expenditure in hospitalized adults diagnosed with obesity utilizing ICD-10 diagnostic coding

The cost and comorbidity of obesity in hospitalized inpatients, is less known. A retrospective study of patients presenting to a large district hospital in Western Sydney (April 2016-February 2017) using clinical, pathological as well as diagnostic coding data for obesity as per ICD-10. Of 43 212 consecutive hospital presentations, 390 had an obesity-coded diagnosis (Ob, 0.90%), of which 244 were gender and age-matched to a non-obesity coded cohort (NOb). Weight and BMI were higher in the Ob vs NOb group (126 ± 37 vs 82 ± 25 kg; BMI 46 ± 12 vs 29 ± 8 kg/m² , P < .001) with a medical record documentation rate of 62% for obesity among Ob. The Ob cohort had 2-5× higher rates of cardiopulmonary and metabolic complications (P < .001), greater pharmacologic burden, length of stay (LOS, 225 vs 89 hours, P < .001) and stay in intensive care but no differences in the prevalence of mental disorders. Compared with BMI <35 kg/m² , inpatients with BMI >35 kg/m² were 5× more likely to require intensive care (OR 5.08 [1.43-27.3, 95% CI], P = .0047). The initiation of obesity-specific interventions by clinical teams was very low. People with obesity who are admitted to hospital carry significant cost and complications, yet obesity is seldom recognized as a clinical entity or contributor.

FLRT2 and FLRT3 Cooperate in Maintaining the Tangential Migratory Streams of Cortical Interneurons during Development

Neuron migration is a hallmark of nervous system development that allows gathering of neurons from different origins for assembling of functional neuronal circuits. Cortical inhibitory interneurons arise in the ventral telencephalon and migrate tangentially forming three transient migratory streams in the cortex before reaching the final laminar destination. Although migration defects lead to the disruption of inhibitory circuits and are linked to aspects of psychiatric disorders such as autism and schizophrenia, the molecular mechanisms controlling cortical interneuron development and final layer positioning are incompletely understood. Here, we show that mouse embryos with a double deletion of FLRT2 and FLRT3 genes encoding cell adhesion molecules exhibit an abnormal distribution of interneurons within the streams during development, which in turn, affect the layering of somatostatin+ interneurons postnatally. Mechanistically, FLRT2 and FLRT3 proteins act in a noncell-autonomous manner, possibly through a repulsive mechanism. In support of such a conclusion, double knockouts deficient in the repulsive receptors for FLRTs, Unc5B and Unc5D, also display interneuron defects during development, similar to the FLRT2/FLRT3 mutants. Moreover, FLRT proteins are chemorepellent ligands for developing interneurons in vitro, an effect that is in part dependent on FLRT-Unc5 interaction. Together, we propose that FLRTs act through Unc5 receptors to control cortical interneuron distribution in a mechanism that involves cell repulsion.SIGNIFICANCE STATEMENT Disruption of inhibitory cortical circuits is responsible for some aspects of psychiatric disorders such as schizophrenia or autism. These defects include interneuron migration during development. A crucial step during this process is the formation of three transient migratory streams within the developing cortex that determine the timing of interneuron final positioning and the formation of functional cortical circuits in the adult. We report that FLRT proteins are required for the proper distribution of interneurons within the cortical migratory streams and for the final laminar allocation in the postnatal cortex. These results expand the multifunctional role of FLRTs during nervous system development in addition to the role of FLRTs in axon guidance and the migration of excitatory cortical neurons.

Natural loss of function of ephrin-B3 shapes spinal flight circuitry in birds

Flight in birds evolved through patterning of the wings from forelimbs and transition from alternating gait to synchronous flapping. In mammals, the spinal midline guidance molecule ephrin-B3 instructs the wiring that enables limb alternation, and its deletion leads to synchronous hopping gait. Here, we show that the ephrin-B3 protein in birds lacks several motifs present in other vertebrates, diminishing its affinity for the EphA4 receptor. The avian ephrin-B3 gene lacks an enhancer that drives midline expression and is missing in galliforms. The morphology and wiring at brachial levels of the chicken embryonic spinal cord resemble those of ephrin-B3 null mice. Dorsal midline decussation, evident in the mutant mouse, is apparent at the chick brachial level and is prevented by expression of exogenous ephrin-B3 at the roof plate. Our findings support a role for loss of ephrin-B3 function in shaping the avian brachial spinal cord circuitry and facilitating synchronous wing flapping.

Recent advances in inter-cellular interactions during neural circuit assembly

Neural circuit assembly is regulated by inter-cellular interactions involving secreted and surface-tethered guidance molecules. Here, we review recent progress in our understanding of their mechanisms-of-action and biological effects. We discuss mechanisms through which the secreted cue Netrin-1 regulates neuron migration and highlight novel roles for axon-derived secreted guidance cues. We cover recent structural work at atomic resolution that provides new insights into the activation mechanisms of axon guidance receptors and into protein complexes containing cell adhesion molecules, such as Teneurin (Ten), Latrophilin (Lphn) and FLRT. Ten-Ten homophilic, Ten-Lphn heterophilic, and Ten-Lphn-FLRT tripartite complexes seem to elicit distinct context-dependent cellular responses. Seemingly opposite responses can also be triggered by the Eph/ephrin signaling system. Here, recent work provides a simple mechanism for the decision of forming a new synapse versus rejection of the pre-synaptic partner. These studies identify novel regulatory mechanisms and biological functions that will apply generally in developing neural systems.

Theory and simulation of open systems out of equilibrium

We consider the theoretical model of Bergmann and Lebowitz for open systems out of equilibrium and translate its principles in the adaptive resolution simulation molecular dynamics technique. We simulate Lennard-Jones fluids with open boundaries in a thermal gradient and find excellent agreement of the stationary responses with the results obtained from the simulation of a larger locally forced closed system. The encouraging results pave the way for a computational treatment of open systems far from equilibrium framed in a well-established theoretical model that avoids possible numerical artifacts and physical misinterpretations.

AB0029 INHIBITION OF EFFECTOR B CELLS BY IBRUTINIB IN SYSTEMIC SCLEROSIS

Background:

Systemic sclerosis (SSc) is a connective tissue disease with significant morbidity and mortality. Effective treatment is still missing, and clinical control of the disease remains challenging. In particular, the development of pulmonary and cardiac fibrosis and pulmonary hypertension are severe complications responsible for excessive mortality. Currently available treatment strategies – besides aggressive autologous stem cell transplantation which is an option only for selected patients – only alleviate symptoms and slow disease progression. Previous attempts of immunomodulating therapies addressing B cell pathology like rituximab and tocilizumab in SSc showed mixed efficacy1,2

Objectives:

Here, we investigated the therapeutic potential of ibrutinib, a Bruton’s tyrosine kinase (BTK) inhibitor used in B cell malignancies, to alter B cell pathology in SSc in anin vitromodel of autoimmunity.

Methods:

PBMCs and sorted B cells of 24 patients with SSc were used for functional testing after stimulation with hypomethylated DNA fragments (CpG) to induce an innate immune response. The effects of ibrutinib on cytokine production, autoantibody release and activation of the transcription factor NFκB were evaluated via multiplex cytokine assay, ELISA and flow cytometry.

Results:

Ibrutinib was able to reduce the production of the profibrotic hallmark cytokines IL-6 and TNF-α, which are mainly released by the effector B cell population, in response to TLR9-stimulation. Importantly, small doses of ibrutinib (0.1 µM) preserved the production of immunoregulatory IL-10 and IFN-γ while effectively inhibiting the cardinal cytokines of hyperactivated profibrotic effector B cells in SSc. Intracellular cytokine staining of IL-6 in B cell subsets further endorsed the potential of ibrutinib to inhibit B cells in a subset-specific manner, reducing IL-6+naïve B cells significantly but not IL-6+memory B cells. The subset specificity was abolished when high doses of ibrutinib (10 µM) were applied. In a flow cytometry analysis of phosphorylated NFκB, an important transcription factor in the induction of innate immune responses in B cells, significantly less activation was observed with ibrutinib treatment (0.1 µM). Higher doses of ibrutinib were unable to further reduce the abundance of pNFκB.

Conclusion:

Our data could pave the avenue for a clinical application of ibrutinib for patients with SSc as a novel treatment option for the underlying pathogenetic immune imbalance contributing to disease onset and progression.

References:

[1]Khanna, D.et al.Efficacy and Safety of Tocilizumab for the Treatment of Systemic Sclerosis: Results from a Phase 3 Randomized Controlled Trial [abstract]. Arthritis Rheumatol. 2018; 70 (suppl 10).

[2]Jordan, S.et al.Effects and safety of rituximab in systemic sclerosis: an analysis from the European Scleroderma Trial and Research (EUSTAR) group.Ann. Rheum. Dis.74, 1188–1194 (2015).

Disclosure of Interests:

Jakob Einhaus: None declared, Ann-Christin Pecher: None declared, Elisa Asteriti: None declared, Hannes Schmid: None declared, Kathy-Ann Secker: None declared, Silke Duerr-Stoerzer: None declared, Hildegard Keppeler: None declared, Reinhild Klein: None declared, Corina Schneidawind: None declared, Jörg Henes Grant/research support from: Novartis, Roche-Chugai, Consultant of: Novartis, Roche, Celgene, Pfizer, Abbvie, Sanofi, Boehringer-Ingelheim,, Dominik Schneidawind: None declared

Monocyte-derived dendritic cells display a highly activated phenotype and altered function in patients with familial Mediterranean fever

Dendritic cells (DCs) are sentinels of the immune system that bridge innate and adaptive immunity. By capturing antigens in peripheral tissue, processing and presenting them with concurrent expression of co‐stimulatory molecules and cytokine secretion they control and modulate immune reactions. Through pattern recognition receptors, DCs sense molecules that are associated with infection or tissue damage, frequently resulting in the formation of inflammasomes upon intracellular stimulation. The inherited autoinflammatory familial Mediterranean fever (FMF) is associated with deregulated activity of the pyrin inflammasome leading to acute inflammatory episodes. However, differentiation and function of DCs in this disease are as yet unclear. Therefore, we first determined DC subpopulation frequency in peripheral blood of a cohort of FMF patients. Joint evaluation without classification according to specific patient characteristics, such as mutational status, did not disclose significant differences compared to healthy controls. For the further examination of phenotype and function, we used immature and mature monocyte‐derived DCs (imMo‐DCs, mMo‐DCs) that were generated in vitro from FMF patients. Immunophenotypical analysis of imMo‐DCs revealed a significantly elevated expression of CD83, CD86 and human leukocyte antigen D‐related (HLA‐DR) as well as a significant down‐regulation of CD206, CD209 and glycoprotein NMB (GPNMB) in our FMF patient group. Furthermore, FMF imMo‐DCs presented a significantly higher capacity to migrate and to stimulate the proliferation of unmatched allogeneic T cells. Finally, the transition towards a more mature, and therefore activated, phenotype was additionally reinforced by the fact that peripheral blood DC populations in FMF patients exhibited significantly increased expression of the co‐stimulatory molecule CD86.

[Acceptance of "voices" in people with or without psychiatric disorders: Francophone validation of the 9-item VAAS scale]

OBJECTIVES

Hearing voices is a common experience for people with schizophrenia. Perceived voices are in most cases a source of great distress for patients. This experience also exists in the general population and is considered as "non-clinical". Much research has focused on the psychological and neuropsychological mechanisms behind the emergence of voices. With regard to voice persistence factors, the acceptance of the voice-hearing phenomenon is still relatively unexplored. In addition, there are few standardized tools that specifically assess this dimension of voice experience. The Voices Acceptance and Actions Scale (VAAS) is the only validated tool to address voice acceptance in individuals with schizophrenia. However, to date, there is no French version. The objective of this research was to validate the VAAS in a French speaking population.

METHOD

Our sample consisted of individuals with schizophrenia (N=65) and voice hearers from the general population (N=321). For the clinical population, individuals with schizophrenia and auditory hallucinations were assessed using the VAAS scale in its two abbreviated versions (9 and 12 items). In order to validate the measure in French, we administered psychopathology scales (BPRS) and voice belief scales (BAVQ-R) for convergent and divergent validity. For the non-clinical population, we administered the VAAS scale online (via LimeSurvey), accompanied by a brief sociodemographic questionnaire (age, sex, country of origin, existence of medical or psychological follow-up).

RESULTS

The psychometric properties of the VAAS scale were satisfactory and similar to the original English-language tool for both versions, with a slight advantage for the one with 9-items. The convergent validity measured with the BAVQ-R scale, and the divergent one measured with the BPRS depression subscale, were found to be satisfactory. In addition, the re-test performed 6 weeks after the first test (N=30) was satisfactory for both scales, with a Pearson correlation index greater than 70 (r=0.70; P<0.001 for the VAAS 9 items) and (r=0.79; P<0.001 for the 12 item version). In individuals with schizophrenia (clinical population), the level of voice acceptance was low and strongly correlated with depression. This point seems to corroborate the current data in the field suggesting that voice hearing in this population is associated with significant distress and has a significant impact on their lives. Conversely, the level of acceptance obtained from the non-clinical population was much higher, reflecting a higher level of acceptance in this population. People from the non-clinical population seemed to accept and experience their voices with less distress than people from the clinical population in this study.

CONCLUSION

To date, a paucity of studies have investigated the acceptance of auditory hallucinations. Our results support the psychometric validity of the French version of the VAAS, particularly the 9-item version. Furthermore, our study supports the need to continue studying voice acceptance, as it appears to be strongly linked to depression in people with psychiatric disorders such as schizophrenia. In addition, our study is novel in that it also explored, with a standardized tool, the level of voice acceptance in a non-clinical population and found people to be more accepting of the voices they hear and better at living with them. These data provide new evidence to better understand the links between the level of acceptance of voices, their experiences, and depression. Clinically, it seems essential to conduct more systematic and regular evaluations of the level of voice acceptance in those hearing voices. Finally, in terms of rehabilitation, voice acceptance can become a therapeutic target in order to improve the psychological and behavioral functioning of the person.

Structural Basis of Teneurin-Latrophilin Interaction in Repulsive Guidance of Migrating Neurons

Teneurins are ancient metazoan cell adhesion receptors that control brain development and neuronal wiring in higher animals. The extracellular C terminus binds the adhesion GPCR Latrophilin, forming a trans-cellular complex with synaptogenic functions. However, Teneurins, Latrophilins, and FLRT proteins are also expressed during murine cortical cell migration at earlier developmental stages. Here, we present crystal structures of Teneurin-Latrophilin complexes that reveal how the lectin and olfactomedin domains of Latrophilin bind across a spiraling beta-barrel domain of Teneurin, the YD shell. We couple structure-based protein engineering to biophysical analysis, cell migration assays, and in utero electroporation experiments to probe the importance of the interaction in cortical neuron migration. We show that binding of Latrophilins to Teneurins and FLRTs directs the migration of neurons using a contact repulsion-dependent mechanism. The effect is observed with cell bodies and small neurites rather than their processes. The results exemplify how a structure-encoded synaptogenic protein complex is also used for repulsive cell guidance.

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Crystal structures reveal binding site for Latrophilin on the Teneurin YD shell

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A ternary Latrophilin-Teneurin-FLRT complex forms in vitro and in vivo

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Latrophilin controls cortical migration by binding to Teneurins and FLRTs

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Latrophilin elicits repulsion of cortical cell bodies/small neurites but not axons

Optimization and diagnostic evaluation of monoclonal antibody-based blocking ELISA formats for detection of neutralizing antibodies to Hendra virus in mammalian sera

Maintenance of Hendra virus (HeV) in pteropid bat populations has been associated with spillover events in horses, humans and dogs. Experimental studies have demonstrated infections for several other species including guinea pigs, cats and ferrets. The criteria of a sensitive and specific serological test that is effective for a range of species, but which does not require use of live virus, has not been satisfactorily addressed by currently available tests. We have evaluated the use of two HeV neutralizing monoclonal antibodies (mAbs) in a blocking format enzyme-linked immunosorbent assay (bELISA) to detect serum antibody against a recombinant expressed HeV G protein (sol G) in several animal species. The human mAb m102.4 neutralises both HeV and the closely related Nipah virus (NiV); the mouse mAb 1.2 neutralises only HeV. Given these functional differences, we have investigated both antibodies using a bELISA format. Diagnostic sensitivity (DSe) and diagnostic specificity (DSp) were optimized using individual thresholds for mAb 1.2 and m102.4. For mAb 1.2 the positive threshold of >33% inhibition yielded DSe and DSp values of 100% (95% CI 95.3-100.0) and 99.5 (95% CI 98.8-99.8) respectively; for mAb m102.4 a positive threshold of >49% inhibition gave DSe and DSp values of 100 (95% CI 95.3-100.0) and 99.8 (95% CI 99.2-100.0) respectively. At these thresholds the DSe was 100% for both tests relative to the virus neutralization test. Importantly, the occurrence of false positive reactions did not overlap across the assays. Therefore, by sequential and selective application of these assays, it is possible to identify false positive reactions and achieve a DSp that approximates 100% in the test population.

Gulp1 controls Eph/ephrin trogocytosis and is important for cell rearrangements during development

Trogocytosis, intercellular cannibalism distinct from phagocytosis, occurs when cells rearrange during development. Here, Gong et al. reveal that trogocytosis induced by ephrins and Eph receptors involves phagocytic adaptor protein Gulp1, Rac-specific guanine nucleotide exchange factor Tiam2, and endocytic GTPase dynamin. These results suggest that ephrin/Eph-induced trogocytosis uses phagocytosis-like mechanisms.

Trogocytosis, in which cells nibble away parts of neighboring cells, is an intercellular cannibalism process conserved from protozoa to mammals. Its underlying molecular mechanisms are not well understood and are likely distinct from phagocytosis, a process that clears entire cells. Bi-directional contact repulsion induced by Eph/ephrin signaling involves transfer of membrane patches and full-length Eph/ephrin protein complexes between opposing cells, resembling trogocytosis. Here, we show that the phagocytic adaptor protein Gulp1 regulates EphB/ephrinB trogocytosis to achieve efficient cell rearrangements of cultured cells and during embryonic development. Gulp1 mediates trogocytosis bi-directionally by dynamic engagement with EphB/ephrinB protein clusters in cooperation with the Rac-specific guanine nucleotide exchange factor Tiam2. Ultimately, Gulp1’s presence at the Eph/ephrin cluster is a prerequisite for recruiting the endocytic GTPase dynamin. These results suggest that EphB/ephrinB trogocytosis, unlike other trogocytosis events, uses a phagocytosis-like mechanism to achieve efficient membrane scission and engulfment.

Cortical circuit alterations precede motor impairments in Huntington's disease mice

Huntington's disease (HD) is a devastating hereditary movement disorder, characterized by degeneration of neurons in the striatum and cortex. Studies in human patients and mouse HD models suggest that disturbances of neuronal function in the neocortex play an important role in disease onset and progression. However, the precise nature and time course of cortical alterations in HD have remained elusive. Here, we use chronic in vivo two-photon calcium imaging to longitudinally monitor the activity of identified single neurons in layer 2/3 of the primary motor cortex in awake, behaving R6/2 transgenic HD mice and wildtype littermates. R6/2 mice show age-dependent changes in cortical network function, with an increase in activity that affects a large fraction of cells and occurs rather abruptly within one week, preceeding the onset of motor defects. Furthermore, quantitative proteomics demonstrate a pronounced downregulation of synaptic proteins in the cortex, and histological analyses in R6/2 mice and human HD autopsy cases reveal a reduction in perisomatic inhibitory synaptic contacts on layer 2/3 pyramidal cells. Taken together, our study provides a time-resolved description of cortical network dysfunction in behaving HD mice and points to disturbed excitation/inhibition balance as an important pathomechanism in HD.

Backyard pigs are a reservoir of zoonotic hepatitis E virus in southern Brazil

Background

Hepatitis E virus (HEV) is the causative agent of acute hepatitis worldwide. There is no seroprevalence study in backyard farms, which are characterized by suboptimal hygienic conditions in Brazil. We aimed to determine the seroprevalence and genetic diversity of HEV in backyard pigs in Brazil.

Methods

Swine serum samples collected in 2012 (n=731) and 2014 (n=713) were analysed. The presence of anti-HEV immunoglobulin G in pig serum was evaluated by indirect enzyme-linked immunosorbent assay. Reverse transcription polymerase chain reaction was performed and phylogenetic analyses were carried out based on the partial ORF1 and ORF2 coding regions.

Results

Anti-HEV antibodies were detected in 77.6% (567/731; 95% confidence interval [CI] 74.5 to 90.6%) of serum samples in 2012 and 65.5% (467/713; 95% CI 62.0 to 69.0%) in 2014. The herd seroprevalence was 91.7% (187/204; 95% CI 91% to 99%) in 2012 and 83.7% (164/196; 95% CI 78% to 89%) in 2014. Further, HEV RNA was detected in 0.8% (6/713) of samples from 2014. Phylogenetic analysis showed three different genotype 3 subtypes with high similarity to human HEV strains.

Conclusions

This study showed that backyard pigs are a reservoir of HEV and alerts us to the need to control infection and spillover from backyard farms.

GenBank accession numbers

MF438128-MF438135.

Probing spatial locality in ionic liquids with the grand canonical adaptive resolution molecular dynamics technique

We employ the Grand Canonical Adaptive Resolution Simulation (GC-AdResS) molecular dynamics technique to test the spatial locality of the 1-ethyl 3-methyl imidazolium chloride liquid. In GC-AdResS, atomistic details are kept only in an open sub-region of the system while the environment is treated at coarse-grained level; thus, if spatial quantities calculated in such a sub-region agree with the equivalent quantities calculated in a full atomistic simulation, then the atomistic degrees of freedom outside the sub-region play a negligible role. The size of the sub-region fixes the degree of spatial locality of a certain quantity. We show that even for sub-regions whose radius corresponds to the size of a few molecules, spatial properties are reasonably reproduced thus suggesting a higher degree of spatial locality, a hypothesis put forward also by other researchers and that seems to play an important role for the characterization of fundamental properties of a large class of ionic liquids.

Spatiotemporal Proteomic Profiling of Huntington's Disease Inclusions Reveals Widespread Loss of Protein Function

Aggregation of polyglutamine-expanded huntingtin exon 1 (HttEx1) in Huntington’s disease (HD) proceeds from soluble oligomers to late-stage inclusions. The nature of the aggregates and how they lead to neuronal dysfunction is not well understood. We employed mass spectrometry (MS)-based quantitative proteomics to dissect spatiotemporal mechanisms of neurodegeneration using the R6/2 mouse model of HD. Extensive remodeling of the soluble brain proteome correlated with insoluble aggregate formation during disease progression. In-depth and quantitative characterization of the aggregates uncovered an unprecedented complexity of several hundred proteins. Sequestration to aggregates depended on protein expression levels and sequence features such as low-complexity regions or coiled-coil domains. In a cell-based HD model, overexpression of a subset of the sequestered proteins in most cases rescued viability and reduced aggregate size. Our spatiotemporally resolved proteome resource of HD progression indicates that widespread loss of cellular protein function contributes to aggregate-mediated toxicity.

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Spatiotemporally resolved brain proteome of wild-type and HD mice

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Quantitative characterization of huntingtin inclusion bodies in vivo

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Sequestration correlates with protein expression levels and specific sequence features

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Resupplying sequestered proteins ameliorates HTT-induced toxicity and inclusion size

Experimental Hendra virus infection of dogs: virus replication, shedding and potential for transmission

OBJECTIVE

Characterisation of experimental Hendra virus (HeV) infection in dogs and assessment of associated transmission risk.

METHODS

Beagle dogs were exposed oronasally to Hendra virus/Australia/Horse/2008/Redlands or to blood collected from HeV-infected ferrets. Ferrets were exposed to oral fluids collected from dogs after canine exposure to HeV. Observations made and samples tested post-exposure were used to assess the clinical course and replication sites of HeV in dogs, the infectivity for ferrets of canine oral fluids and features of HeV infection in dogs following contact with infective blood.

RESULTS

Dogs were reliably infected with HeV and were generally asymptomatic. HeV was re-isolated from the oral cavity and virus clearance was associated with development of virus neutralising antibody. Major sites of HeV replication in dogs were the tonsils, lower respiratory tract and associated lymph nodes. Virus replication was documented in canine kidney and spleen, confirming a viraemic phase for canine HeV infection and suggesting that urine may be a source of infectious virus. Infection was transmitted to ferrets via canine oral secretions, with copy numbers for the HeV N gene in canine oral swabs comparable to those reported for nasal swabs of experimentally infected horses.

CONCLUSION

HeV is not highly pathogenic for dogs, but their oral secretions pose a potential transmission risk to people. The time-window for transmission risk is circumscribed and corresponds to the period of acute infection before establishment of an adaptive immune response. The likelihood of central nervous system involvement in canine HeV infection is unclear, as is any long-term consequence.

Oxidative Stress and Cardiovascular Risk in Type 1 Diabetes Mellitus: Insights From the DCCT/EDIC Study

Background

Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus.

Methods and Results

A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P <0.003; −5.3% risk for 10% higher 2,3 dinor‐8 iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments.

Conclusions

Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control.

Clinical Trial Registration

URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

Lp(a) is not Related to Retinopathy in Diabetic Subjects

PURPOSE

To examine the association between Lp(a) concentrations and the severity of retinopathy in 22 younger-onset and 48 older-onset diabetic subjects from the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR), a population-based study of diabetic retinopathy.

METHODS

We used a subset of the WESDR population with standardized protocols and stereoscopic color fundus photography to determine the severity of diabetic retinopathy in relation to Lp(a) concentrations. Lp(a) concentrations were measured by a monoclonal anti-Lp(a) antibody.

RESULTS

Lp(a) levels were not significantly different between younger-onset or older-onset subjects with and without retinopathy.

CONCLUSION

Our results do not support a link between higher levels of Lp(a) and severe retinopathy in either younger-onset or older-onset diabetic subjects but this needs confirmation in larger prospective studies.

A Pilot Study of Glaucoma Visual Field Screening in Diabetes

Because people with diabetes may be at increased risk of glaucoma, we performed a pilot study using automated visual field testing for screening them. One hundred and seventy-six diabetic persons who had participated in the Wisconsin Epidemiologic Study of Diabetic Retinopathy were tested with the Armaly-Drance screening pattern on the Humphrey Visual Field Analyzer. Individuals with moderate diabetic retinopathy or worse tended to have lower sensitivity of the central visual field and missed more points than those with no or only mild retinopathy. People with a history of glaucoma had slightly less sensitivity and missed more points than controls. These preliminary findings suggest that although people with diabetes and glaucoma may more frequently have visual field defects than people with diabetes but no glaucoma, a larger study is needed. This pilot study shows that such a study would be feasible and should be designed to indicate the sensitivity, specificity, and cost-benefit ratio of a screening program so as to assess the utility of the screening visual field test for finding glaucoma amongst people with diabetes.

A Syndrome Associated with Left Hand Paralysis of Central Origin

Certain disturbances of a higher order, e.g. aphasia and agnosia, follow as a rule a lesion of the left hemisphere in right-handed persons and vice versa. This dominance of one hemisphere for certain functions has been well established from abundant material. The Gerstmann Syndrome, recently studied, seems to obey the same rule of dominance; other disorders, such as the attitude toward paralysed limbs and defective functions, appear to be caused by lesions of the non-dominant hemisphere. The relations of the latter group, however, to the hemisphere cannot be regarded as firmly established, since the material presented is still limited.

Pupillary Phenomena on Application of a Strong Constant Electric Current As Used in Electronarcotic Treatment

In the usual procedure of electronarcotic treatment, the electrodes are placed bitemporally and an initial electric current of 180 m.a. is applied for 30 seconds. During this period a tonic extension of the skeletal muscles occurs, accompanied by strong contraction of the pupils, which in the majority of cases are reduced to pin-point size. Slight convergence of the eyes may accompany the contraction. The contraction relaxes somewhat when clonus ensues, but usually becomes slightly more marked in the following stage when the electric current applied is between 60 and 80 m.a.

Clinical and Biochemical Analysis of a Case of Manic-Depressive Psychosis Showing Regular Weekly Cycles

The unfailing regularity of the rhythm of his manic-depressive cycles each week renders the patient in question particularly suitable for investigation, and throws into relief changes which might be less marked if the transition between the phases was more gradual and the periodicity less certain.

Observations on the Electrically-Produced Epileptic Convulsion. Part II: Pupillary Phenomena in Normal and Pathological Pupils

There are three particular pupillary movements in the course of the electrically-produced epileptic fit: dilatation during the convulsion, constriction in the post-convulsive stage, and spasmodic dilatation towards the final stages of the post-convulsive stage. The pupillary dilatation in the convulsive phase is identical with that found in the spontaneous epileptic fit, where it is generally considered as an expression of sympathetic activity, either the consequence of a general (Bumke, 1914) or of a focal cortical excitation (Foerster, 1936; Penfield and Erickson, 1941), or, an opinion held more recently, due to a hypothalamic mechanism (Delay, 1946).

Observations in Electrically-Produced Epileptic Convulsions

The pattern of the epileptiform fit produced by electric shock treatment is fairly uniform and constant. The four stages of the fit—the preconvulsive, tonic, clonic and post-convulsive phases—are characteristically expressed in postures and movements of eyes and head in each phase.

Clinical and Biochemical Investigations in a Manic-Depressive with Short Cycles

Results of a previous investigation of manic-depressive psychosis with a continuity of cycles of short duration (Klein and Nunn, 1945) seemed to justify further study of this group. As such cases suitable for investigation are rare, we are again reporting observations on a single case, although the cycles were not as short and regular as in the earlier case. The patient at the time of his last admission to this hospital (in 1944) was aged 40, married, had a healthy child of 16, and was an employee of a tobacco factory. He was said to have been always very quiet and reserved, and had no history of mental illness before joining the Army in 1941. He went to the Middle East in July, 1942, and began to feel listless, tired and sleepless for the first time at the beginning of 1943. After spending four weeks in a military hospital he still felt low on returning to his unit, but soon afterwards was full of life; in his own words, “I could tear anything down.” A fresh period of depression set in later, and he was sent to a military mental hospital for six months, during which time he apparently changed several times from a depressive state into a manic one in which he felt “overstowed with vitality,” “with the energy of ten men.” From this hospital he was returned to England and invalided from the army in October, 1943, at which date he first became a patient in this hospital. An initial depression of about three weeks was followed by a manic condition, and on becoming more settled he took his discharge (at the beginning of December, 1943). In February, 1944, he was readmitted in depression, but went out again whilst in moderate mania in April. Whilst at home he continued his work in the factory, but in September, 1944, was once more admitted to hospital and has since remained. From the latter date till October, 1948, depressive periods have alternated with manic conditions. Wide variations have been noted in the duration of the two phases; at the beginning of the observation period of 21 cycles the manic state lasted longer than the depression, whilst in the last year the reverse was usually true. Manic periods varied between one week and 35 days, with an average of 18 days, while the variation shown by depressive phases was between 6 and 24 days, with an average of 13 days.

Compensatory Enlargement of the Posterior Communicating Artery Following Arterio-Sclerotic Changes of the Posterior Cerebral Artery

While a vast literature refers to anomalies in various arteries of the brain, there are only a few reports concerning anatomical changes of vessels following altered circulatory conditions. Critchley mentions in his study of the anterior cerebral artery and its syndromes, an observation in which an arterio-sclerotic anterior cerebral artery of one side was so small as to be incapable of maintaining an adequate circulation, so that by way of an abnormally large anterior communicating artery the opposite anterior cerebral supplied both hemispheres. Critchley adds to that case several similar observations from the literature. The application of arteriography to circulatory disturbances has directed attention to analogous cases. Thus Moniz reported several observations in which a closure of the carotid artery of one side led to a distension of the anterior communicating in order to establish collateral circulation. The same mechanism appeared to be effective in the following two cases which we met in the course of our studies on brain vessels.

Contribution to the Dressing Disability As a Focal Sign and to the Imperception Phenomena

Inability to dress oneself is a rare symptom in focal brain lesions. We have observed it in two cases, a tumour expanding between the cerebral hemispheres, and a case of head injury in which the mental condition was sufficiently intact to allow a detailed analysis: In discussing the imperception phenomena of the tumour case, we have referred to certain others of relevant interest.

In Situ Architecture and Cellular Interactions of PolyQ Inclusions

Expression of many disease-related aggregation-prone proteins results in cytotoxicity and the formation of large intracellular inclusion bodies. To gain insight into the role of inclusions in pathology and the in situ structure of protein aggregates inside cells, we employ advanced cryo-electron tomography methods to analyze the structure of inclusions formed by polyglutamine (polyQ)-expanded huntingtin exon 1 within their intact cellular context. In primary mouse neurons and immortalized human cells, polyQ inclusions consist of amyloid-like fibrils that interact with cellular endomembranes, particularly of the endoplasmic reticulum (ER). Interactions with these fibrils lead to membrane deformation, the local impairment of ER organization, and profound alterations in ER membrane dynamics at the inclusion periphery. These results suggest that aberrant interactions between fibrils and endomembranes contribute to the deleterious cellular effects of protein aggregation. VIDEO ABSTRACT.

Placental labyrinth formation in mice requires endothelial FLRT2/UNC5B signaling

The placental labyrinth is the interface for gas and nutrient exchange between the embryo and the mother; hence its proper development is essential for embryogenesis. However, the molecular mechanism underlying development of the placental labyrinth, particularly in terms of its endothelial organization, is not well understood. Here, we determined that fibronectin leucine-rich transmembrane protein 2 (FLRT2), a repulsive ligand of the UNC5 receptor family for neurons, is unexpectedly expressed in endothelial cells specifically in the placental labyrinth. Mice lacking FLRT2 in endothelial cells exhibited embryonic lethality at mid-gestation, with systemic congestion and hypoxia. Although they lacked apparent deformities in the embryonic vasculature and heart, the placental labyrinths of these embryos exhibited aberrant alignment of endothelial cells, which disturbed the feto-maternal circulation. Interestingly, this vascular deformity was related to endothelial repulsion through binding to the UNC5B receptor. Our results suggest that the proper organization of the placental labyrinth depends on coordinated inter-endothelial repulsion, which prevents uncontrolled layering of the endothelium.

Phosphorylation of lignin: characterization and investigation of the thermal decomposition

Lignin is an abundant polyphenol biopolymeric material chemically functionalisable to act as flame retardant in polymers.