The paraventricular thalamic nucleus (PVT) is a part of epithalamus and sends outputs to emotion-related brain areas such as the medial prefrontal cortex, nucleus accumbens, and amygdala. Various ...functional roles of the PVT in emotion-related behaviors are drawing attention. Here, we investigated the effect of manipulation of PVT neurons on the firing patterns of medial prefrontal cortical (mPFC) neurons and depression-like behavior. Extracellular single-unit recordings revealed that acute activation of PVT neurons by hM3Dq, an activation type of designer receptors exclusively activated by designer drugs (DREADDs), and administration of clozapine N-oxide (CNO) caused firing rate changes in mPFC neurons. Moreover, chronic presynaptic inhibition in PVT neurons by tetanus toxin (TeTX) increased the proportion of interneurons among firing neurons in mPFC and shortened the immobility time in the forced swimming test, whereas long-term activation of PVT neurons by hM3Dq caused recurrent hypoactivity episodes. These findings suggest that PVT neurons regulate the excitation/inhibition balance in the mPFC and mood stability.
The Japanese Society of Mood Disorders established a committee for treatment guidelines of mood disorders, which created the first edition of a treatment guideline for bipolar disorders on 10 March ...2011. The committee has now created a second edition, which we report here. In creating this treatment guideline, the first step was to have several bipolar disorder specialists review well‐conducted studies and meta‐analyses. Based on this evidence, and with a consensus among the specialists, treatment procedures that were considered optimal were compiled and the strength of recommendation for each treatment method was determined. The first draft, prepared in this manner, was further revised through a process of critical investigation by all committee members to produce the final edition.
Substantial evidence suggests that chromosomal abnormalities contribute to the risk of autism. The duplication of human chromosome 15q11-13 is known to be the most frequent cytogenetic abnormality in ...autism. We have modeled this genetic change in mice by using chromosome engineering to generate a 6.3 Mb duplication of the conserved linkage group on mouse chromosome 7. Mice with a paternal duplication display poor social interaction, behavioral inflexibility, abnormal ultrasonic vocalizations, and correlates of anxiety. An increased MBII52 snoRNA within the duplicated region, affecting the serotonin 2c receptor (5-HT2cR), correlates with altered intracellular Ca2+ responses elicited by a 5-HT2cR agonist in neurons of mice with a paternal duplication. This chromosome-engineered mouse model for autism seems to replicate various aspects of human autistic phenotypes and validates the relevance of the human chromosome abnormality. This model will facilitate forward genetics of developmental brain disorders and serve as an invaluable tool for therapeutic development.
Abstract
A report of a family of Darier’s disease with mood disorders drew attention when the causative gene was identified as ATP2A2 (or SERCA2), which encodes a Ca2+ pump on the endoplasmic ...reticulum (ER) membrane and is important for intracellular Ca2+ signaling. Recently, it was found that loss-of-function mutations of ATP2A2 confer a risk of neuropsychiatric disorders including depression, bipolar disorder and schizophrenia. In addition, a genome-wide association study found an association between ATP2A2 and schizophrenia. However, the mechanism of how ATP2A2 contributes to vulnerability to these mental disorders is unknown. Here, we analyzed Atp2a2 heterozygous brain-specific conditional knockout (hetero cKO) mice. The ER membranes prepared from the hetero cKO mouse brain showed decreased Ca2+ uptake activity. In Atp2a2 heterozygous neurons, decays of cytosolic Ca2+ level were slower than control neurons after depolarization. The hetero cKO mice showed altered behavioral responses to novel environments and impairments in fear memory, suggestive of enhanced dopamine signaling. In vivo dialysis demonstrated that extracellular dopamine levels in the NAc were indeed higher in the hetero cKO mice. These results altogether indicate that the haploinsufficiency of Atp2a2 in the brain causes prolonged cytosolic Ca2+ transients, which possibly results in enhanced dopamine signaling, a common feature of mood disorders and schizophrenia. These findings elucidate how ATP2A2 mutations causing a dermatological disease may exert their pleiotropic effects on the brain and confer a risk for mental disorders.
COVID-19 has a range of complications, from no symptoms to severe pneumonia. It can also affect multiple organs including the nervous system. COVID-19 affects the brain, leading to neurological ...symptoms such as delirium. Delirium, a sudden change in consciousness, can increase the risk of death and prolong the hospital stay. However, research on delirium prediction in patients with COVID-19 is insufficient. This study aimed to identify new risk factors that could predict the onset of delirium in patients with COVID-19 using machine learning (ML) applied to nursing records. This retrospective cohort study used natural language processing and ML to develop a model for classifying the nursing records of patients with delirium. We extracted the features of each word from the model and grouped similar words. To evaluate the usefulness of word groups in predicting the occurrence of delirium in patients with COVID-19, we analyzed the temporal changes in the frequency of occurrence of these word groups before and after the onset of delirium. Moreover, the sensitivity, specificity, and odds ratios were calculated. We identified (1) elimination-related behaviors and conditions and (2) abnormal patient behavior and conditions as risk factors for delirium. Group 1 had the highest sensitivity (0.603), whereas group 2 had the highest specificity and odds ratio (0.938 and 6.903, respectively). These results suggest that these parameters may be useful in predicting delirium in these patients. The risk factors for COVID-19-associated delirium identified in this study were more specific but less sensitive than the ICDSC (Intensive Care Delirium Screening Checklist) and CAM-ICU (Confusion Assessment Method for the Intensive Care Unit). However, they are superior to the ICDSC and CAM-ICU because they can predict delirium without medical staff and at no cost.
Introduction
Kato et al. reported results of a 6‐week, double‐blind, randomized, placebo‐controlled trial of lurasidone in adults with bipolar depression (BDep).
Aim
We performed a post hoc analysis ...using data from the lurasidone trial to predict later responses from early improvements.
Methods
An early improvement was defined as a ≥20% reduction in Montgomery–Åsberg Depression Rating Scale (MADRS) total score at Week 2; response was defined as a ≥50% reduction in MADRS total score at Week 6; symptomatic remission were defined as a score of ≤8 on MADRS total score at Week 6.
Results
Both sensitivity and negative predictive value (NPV) were higher for the remission outcome than for the response outcome. The interpretation of sensitivity and NPV in the lurasidone group when remission is an outcome is as follows. It means (1) that, from all remitters at Week 6, 80.6% was identified as such at Week 2 on the basis of their early improvement and (2) that a patient showing non‐improvement at 2 weeks had 93.5% probability of being a non‐remitters at Week 6. However, the values of specificity for both response and remission in the lurasidone group were not high.
Conclusion
Patients who did not show an early response at Week 2 cannot be predicted with a high probability to also show poor improvement at Week 6. In fact, some patients who did not show early response at 2 weeks might have marked improvement at 6 weeks.
We performed a post‐hoc analysis using data from the lurasidone trial to predict later responses from early improvements. Both sensitivity and negative predictive value values were higher for the remission outcome than for the response outcome.
Previously, we reported a family in which bipolar disorder (BD) co-segregates with a Mendelian kidney disorder linked to 1q22. The causative renal gene was later identified as MUC1. Genome-wide ...linkage analysis of BD in the family yielded a peak at 1q22 that encompassed the NTRK1 and MUC1 genes. NTRK1 codes for TrkA (Tropomyosin-related kinase A) which is essential for development of the cholinergic nervous system. Whole genome sequencing of the proband identified a damaging missense mutation, E492K, in NTRK1. Induced pluripotent stem cells were generated from family members, and then differentiated to neural stem cells (NSCs). E492K NSCs had reduced neurite outgrowth. A conditional knock-in mouse line, harboring the point mutation in the brain, showed depression-like behavior in the tail suspension test following challenge by physostigmine, a cholinesterase inhibitor. These results are consistent with the cholinergic hypothesis of depression. They imply that the NTRK1 E492K mutation, impairs cholinergic neurotransmission, and may convey susceptibility to bipolar disorder.
PDF
