Systems biology dissection of PTSD and MDD across brain regions, cell types, and blood.

The molecular pathology of stress-related disorders remains elusive. Our brain multiregion, multiomic study of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) included the central nucleus of the amygdala, hippocampal dentate gyrus, and medial prefrontal cortex (mPFC). Genes and exons within the mPFC carried most disease signals replicated across two independent cohorts.

The gene expression landscape of the human locus coeruleus revealed by single-nucleus and spatially-resolved transcriptomics.

Norepinephrine (NE) neurons in the locus coeruleus (LC) make long-range projections throughout the central nervous system, playing critical roles in arousal and mood, as well as various components of cognition including attention, learning, and memory. The LC-NE system is also implicated in multiple neurological and neuropsychiatric disorders. Importantly, LC-NE neurons are highly sensitive to degeneration in both Alzheimer's and Parkinson's disease.

Single-Nucleus Transcriptome Profiling of Dorsolateral Prefrontal Cortex: Mechanistic Roles for Neuronal Gene Expression, Including the 17q21.31 Locus, in PTSD Stress Response.

Objective: Multidisciplinary studies of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) implicate the dorsolateral prefrontal cortex (DLPFC) in disease risk and pathophysiology. Postmortem brain studies have relied on bulk-tissue RNA sequencing (RNA-seq), but single-cell RNA-seq is needed to dissect cell-type-specific mechanisms. The authors conducted the first single-nucleus RNA-seq postmortem brain study in PTSD to elucidate disease transcriptomic pathology with cell-type-specific resolution.

A validation of discrete-element model simulations for predicting tablet coating variability.

Achieving an even coating distribution on tablets during the coating process can be challenging, not to mention the challenges of accurately measuring and quantifying inter-tablet coating variability. Computer simulations using the Discrete Element Method (DEM) provide a viable pathway towards model-predictive design of coating processes. The purpose of this study was to assess their predictivity accounting for both experimental and simulation input uncertainties.

Orthogonal approaches required to measure proteasome composition and activity in mammalian brain tissue.

Proteasomes are large macromolecular complexes with multiple distinct catalytic activities that are each vital to human brain health and disease. Despite their importance, standardized approaches to investigate proteasomes have not been universally adapted. Here, we describe pitfalls and define straightforward orthogonal biochemical approaches essential to measure and understand changes in proteasome composition and activity in the mammalian central nervous system.

Consensus molecular environment of schizophrenia risk genes in coexpression networks shifting across age and brain regions.

Schizophrenia is a neurodevelopmental brain disorder whose genetic risk is associated with shifting clinical phenomena across the life span. We investigated the convergence of putative schizophrenia risk genes in brain coexpression networks in postmortem human prefrontal cortex (DLPFC), hippocampus, caudate nucleus, and dentate gyrus granule cells, parsed by specific age periods (total  = 833). The results support an early prefrontal involvement in the biology underlying schizophrenia and reveal a dynamic interplay of regions in which age parsing explains more variance in schizophrenia risk compared to lumping all age periods together.

SUFI: an automated approach to spectral unmixing of fluorescent multiplex images captured in mouse and post-mortem human brain tissues.

Background: Multispectral fluorescence imaging coupled with linear unmixing is a form of image data collection and analysis that allows for measuring multiple molecular signals in a single biological sample. Multiple fluorescent dyes, each measuring a unique molecule, are simultaneously measured and subsequently "unmixed" to provide a read-out for each molecular signal. This strategy allows for measuring highly multiplexed signals in a single data capture session, such as multiple proteins or RNAs in tissue slices or cultured cells, but can often result in mixed signals and bleed-through problems across dyes.

Decoding Shared Versus Divergent Transcriptomic Signatures Across Cortico-Amygdala Circuitry in PTSD and Depressive Disorders.

Objective: Posttraumatic stress disorder (PTSD) is a debilitating neuropsychiatric disease that is highly comorbid with major depressive disorder (MDD) and bipolar disorder. The overlap in symptoms is hypothesized to stem from partially shared genetics and underlying neurobiological mechanisms. To delineate conservation between transcriptional patterns across PTSD and MDD, the authors examined gene expression in the human cortex and amygdala in these disorders.

Capsule-Based dry powder inhaler evaluation using CFD-DEM simulations and next generation impactor data.

Capsule-based, single-dose dry powder inhalers (DPIs) are commonly-used devices to deliver medications to the lungs. This work evaluates the effect of the drug/excipient adhesive bonding and the DPI resistances on the aerosol performance using a combination of empirical multi-stage impactor data and a fully-coupled computational fluid dynamics (CFD) and discrete element method (DEM) model. Model-predicted quantities show that the primary modes of powder dispersion are a function of the device resistance.

Integrated DNA methylation and gene expression profiling across multiple brain regions implicate novel genes in Alzheimer's disease.

Late-onset Alzheimer's disease (AD) is a complex age-related neurodegenerative disorder that likely involves epigenetic factors. To better understand the epigenetic state associated with AD, we surveyed 420,852 DNA methylation (DNAm) sites from neurotypical controls (N = 49) and late-onset AD patients (N = 24) across four brain regions (hippocampus, entorhinal cortex, dorsolateral prefrontal cortex and cerebellum). We identified 858 sites with robust differential methylation collectively annotated to 772 possible genes (FDR < 5%, within 10 kb).

Neuroepigenetics of Schizophrenia.

Schizophrenia is a complex disorder of the brain, where genetic variants explain only a portion of risk. Neuroepigenetic mechanisms may explain the remaining share of risk, as well as the transition from susceptibility to the actual disease. Here, we discuss the most recent findings in the field of brain epigenetics applied to the study of schizophrenia.

Hats Off: A Study of Different Operating Room Headgear Assessed by Environmental Quality Indicators.

Background: The effectiveness of operating room headgear in preventing airborne contamination has been called into question. We hypothesized that bouffant style hats would be as effective in preventing bacterial and particulate contamination in the operating room compared with disposable or cloth skull caps, and bouffant style hats would have similar permeability, particle penetration, and porosity compared with skull caps.

Study Design: Disposable bouffant and skull cap hats and newly laundered cloth skull caps were tested.

Implementation and clinical characteristics of a posttraumatic stress disorder brain collection.

A postmortem human brain collection to study posttraumatic stress disorder (PTSD) is critical for uncovering the molecular mechanisms that contribute to this psychiatric disorder. We describe here the PTSD brain collection at the Lieber Institute for Brain Development in Baltimore, Maryland, consisting of postmortem brain donations acquired between 2012 and 2017. Thus far, 87 brains from individuals meeting DSM-5 criteria for PTSD were collected after consent was obtained from legal next-of-kin, and subsequently clinically characterized for molecular studies.

Genetic risk mechanisms of posttraumatic stress disorder in the human brain.

Posttraumatic stress disorder (PTSD) follows exposure to a traumatic event in susceptible individuals. Recently, genome-wide association studies have identified a number of genetic sequence variants that are associated with the risk of developing PTSD. To follow up on identifying the molecular mechanisms of these risk variants, we performed genotype to RNA sequencing-derived quantitative expression (whole gene, exon, and exon junction levels) analysis in the dorsolateral prefrontal cortex (DLPFC) of normal postmortem human brains.

Impact of drug awareness and treatment camps on attendance at a community outreach de-addiction clinic.

Background: Substance misuse is an increasing problem in urban and rural India. The utility of community-based interventions and preventive strategies are increasingly emphasized in this context. The drug de-addiction and treatment center, Department of Psychiatry, Postgraduate Institute of Medical Education and Research, has been running a drug de-addiction and treatment clinic at Kharar Civil Hospital, Kharar, District Mohali, Punjab, since 1998.

Alzheimer Lesions in the Autopsied Brains of People 30 to 50 Years of Age.

Objective: To test the hypothesis that asymptomatic Alzheimer disease lesions may appear before 50 years of age.

Background: Alzheimer disease has an asymptomatic stage during which people are cognitively intact despite having substantial pathologic changes in the brain. While this asymptomatic stage is common in older people, how early in life it may develop has been unknown.

Conserved higher-order chromatin regulates NMDA receptor gene expression and cognition.

Three-dimensional chromosomal conformations regulate transcription by moving enhancers and regulatory elements into spatial proximity with target genes. Here we describe activity-regulated long-range loopings bypassing up to 0.5 Mb of linear genome to modulate NMDA glutamate receptor GRIN2B expression in human and mouse prefrontal cortex.

The genome in three dimensions: a new frontier in human brain research.

Less than 1.5% of the human genome encodes protein. However, vast portions of the human genome are subject to transcriptional and epigenetic regulation, and many noncoding regulatory DNA elements are thought to regulate the spatial organization of interphase chromosomes.

Conserved chromosome 2q31 conformations are associated with transcriptional regulation of GAD1 GABA synthesis enzyme and altered in prefrontal cortex of subjects with schizophrenia.

Little is known about chromosomal loopings involving proximal promoter and distal enhancer elements regulating GABAergic gene expression, including changes in schizophrenia and other psychiatric conditions linked to altered inhibition. Here, we map in human chromosome 2q31 the 3D configuration of 200 kb of linear sequence encompassing the GAD1 GABA synthesis enzyme gene locus, and we describe a loop formation involving the GAD1 transcription start site and intergenic noncoding DNA elements facilitating reporter gene expression. The GAD1-TSS(-50kbLoop) was enriched with nucleosomes epigenetically decorated with the transcriptional mark, histone H3 trimethylated at lysine 4, and was weak or absent in skin fibroblasts and pluripotent stem cells compared with neuronal cultures differentiated from them.

Prefrontal cortical dysfunction after overexpression of histone deacetylase 1.

Background: Postmortem brain studies have shown that HDAC1-a lysine deacetylase with broad activity against histones and nonhistone proteins-is frequently expressed at increased levels in prefrontal cortex (PFC) of subjects diagnosed with schizophrenia and related disease. However, it remains unclear whether upregulated expression of Hdac1 in the PFC could affect cognition and behavior.

Methods: Using adeno-associated virus, an Hdac1 transgene was expressed in young adult mouse PFC, followed by behavioral assays for working and long-term memory, repetitive activity, and response to novelty.