Imaging distinct neuronal populations with a dual channel miniscope.

Miniature fluorescence microscopes (miniscopes) are one of the most powerful and versatile tools for recording large scale neural activity in freely moving rodents with single cell resolution. Recent advances in the design of genetically encoded calcium indicators (GECIs) allow to target distinct neuronal populations with non-overlapping emission spectral profiles. However, conventional miniscopes are limited to a single excitation, single focal plane imaging, which does not allow to compensate for chromatic aberration and image from two spectrally distinct calcium indicators.

Single-extracellular vesicle (EV) analyses validate the use of L1 Cell Adhesion Molecule (L1CAM) as a reliable biomarker of neuron-derived EVs.

Isolation of neuron-derived extracellular vesicles (NDEVs) with L1 Cell Adhesion Molecule (L1CAM)-specific antibodies has been widely used to identify blood biomarkers of CNS disorders. However, full methodological validation requires demonstration of L1CAM in individual NDEVs and lower levels or absence of L1CAM in individual EVs from other cells. Here, we used multiple single-EV techniques to establish the neuronal origin and determine the abundance of L1CAM-positive EVs in human blood.

Approaches and considerations of studying neuronal ensembles: a brief review.

First theorized by Hebb, neuronal ensembles have provided a framework for understanding how the mammalian brain operates, especially regarding learning and memory. Neuronal ensembles are discrete, sparsely distributed groups of neurons that become activated in response to a specific stimulus and are thought to provide an internal representation of the world. Beyond the study of region-wide or projection-wide activation, the study of ensembles offers increased specificity and resolution to identify and target specific memories or associations.

Flow Cytometry of Synaptoneurosomes (FCS) Reveals Increased Ribosomal S6 and Calcineurin Proteins in Activated Medial Prefrontal Cortex to Nucleus Accumbens Synapses.

Learning and behavior activate cue-specific patterns of sparsely distributed cells and synapses called ensembles that undergo memory-encoding engram alterations. While Fos is often used to label selectively activated cell bodies and identify neuronal ensembles, there is no comparable endogenous marker to label activated synapses and identify synaptic ensembles. For the purpose of identifying candidate synaptic activity markers, we optimized a flow cytometry of synaptoneurosome (FCS) procedure for assessing protein alterations in activated synapses from male and female rats.

Chronic conditions in women: the development of a National Institutes of health framework.

Rising rates of chronic conditions were cited as one of the key public health concerns in the Fiscal Year (FY) 2021 U.S. Senate and House of Representatives appropriations bills, where a review of current National Institutes of Health (NIH) portfolios relevant to research on women's health was requested.

Astrocytes mediate cerebral blood flow and neuronal response to cocaine in prefrontal cortex.

Cocaine affects both cerebral blood vessels and neuronal activity in brain. Cocaine can also disrupt astrocytes, which are involved in neurovascular coupling process that modulates cerebral hemodynamics in response to neuronal activity. However, separating neuronal and astrocytic effects from cocaine's direct vasoactive effects is challenging, partially due to limitations of neuroimaging techniques to differentiate vascular from neuronal and glial effects at high temporal and spatial resolutions.

Effect of Selective Lesions of Nucleus Accumbens µ-Opioid Receptor-Expressing Cells on Heroin Self-Administration in Male and Female Rats: A Study with Novel Knock-in Rats.

The brain µ-opioid receptor (MOR) is critical for the analgesic, rewarding, and addictive effects of opioid drugs. However, in rat models of opioid-related behaviors, the circuit mechanisms of MOR-expressing cells are less known because of a lack of genetic tools to selectively manipulate them. We introduce a CRISPR-based knock-in transgenic rat that provides cell type-specific genetic access to MOR-expressing cells.

Rates of Incidental Findings in Brain Magnetic Resonance Imaging in Children.

Importance: Incidental findings (IFs) are unexpected abnormalities discovered during imaging and can range from normal anatomic variants to findings requiring urgent medical intervention. In the case of brain magnetic resonance imaging (MRI), reliable data about the prevalence and significance of IFs in the general population are limited, making it difficult to anticipate, communicate, and manage these findings.

Objectives: To determine the overall prevalence of IFs in brain MRI in the nonclinical pediatric population as well as the rates of specific findings and findings for which clinical referral is recommended.

Food-Seeking Behavior Is Mediated by Fos-Expressing Neuronal Ensembles Formed at First Learning in Rats.

Neuronal ensembles in the infralimbic cortex (IL) develop after prolonged food self-administration training. However, rats demonstrate evidence of learning the food self-administration response as early as day 1, with responding quickly increasing to asymptotic levels. Since the contribution of individual brain regions to task performance shifts over the course of training, it remains unclear whether IL ensembles are gradually formed and refined over the course of extensive operant training, or whether functionally-relevant ensembles might be recruited and formed as early as the initial acquisition of food self-administration behavior.

Separate vmPFC Ensembles Control Cocaine Self-Administration Versus Extinction in Rats.

Recent studies suggest that the ventral medial prefrontal cortex (vmPFC) encodes both operant drug self-administration and extinction memories. Here, we examined whether these opposing memories are encoded by distinct neuronal ensembles within the vmPFC with different outputs to the nucleus accumbens (NAc) in male and female rats. Using cocaine self-administration (3 h/d for 14 d) and extinction procedures, we demonstrated that vmPFC was similarly activated (indexed by Fos) during cocaine-seeking tests after 0 (no-extinction) or 7 extinction sessions.

Nucleus Accumbens Drd1-Expressing Neurons Control Aggression Self-Administration and Aggression Seeking in Mice.

We recently developed a mouse model of appetitive operant aggression and reported that adult male outbred CD-1 mice lever-press for the opportunity to attack subordinate male mice and relapse to aggression seeking during abstinence. Here we studied the role of nucleus accumbens (NAc) dopamine receptor (Drd)1- and Drd2-expressing neurons in aggression self-administration and aggression seeking. We trained CD-1 mice to self-administer intruders (9 d, 12 trials/d) and tested them for aggression self-administration and aggression seeking on abstinence Day 1.

Approaches for creating comparable measures of alcohol use symptoms: Harmonization with eight studies of criminal justice populations.

Background: With increasing data archives comprised of studies with similar measurement, optimal methods for data harmonization and measurement scoring are a pressing need. We compare three methods for harmonizing and scoring the AUDIT as administered with minimal variation across 11 samples from eight study sites within the STTR (Seek-Test-Treat-Retain) Research Harmonization Initiative. Descriptive statistics and predictive validity results for cut-scores, sum scores, and Moderated Nonlinear Factor Analysis scores (MNLFA; a psychometric harmonization method) are presented.

Cell-Type-Specific Role of ΔFosB in Nucleus Accumbens In Modulating Intermale Aggression.

A growing number of studies implicate the brain's reward circuitry in aggressive behavior. However, the cellular and molecular mechanisms within brain reward regions that modulate the intensity of aggression as well as motivation for it have been underexplored. Here, we investigate the cell-type-specific influence of ΔFosB, a transcription factor known to regulate a range of reward and motivated behaviors, acting in the nucleus accumbens (NAc), a key reward region, in male aggression in mice.

Subjective and physiological effects, and expired carbon monoxide concentrations in frequent and occasional cannabis smokers following smoked, vaporized, and oral cannabis administration.

Background: Although smoking is the most common cannabis administration route, vaporization and consumption of cannabis edibles are common. Few studies directly compare cannabis' subjective and physiological effects following multiple administration routes.

Methods: Subjective and physiological effects, and expired carbon monoxide (CO) were evaluated in frequent and occasional cannabis users following placebo (0.

Distinct memory engrams in the infralimbic cortex of rats control opposing environmental actions on a learned behavior.

Conflicting evidence exists regarding the role of infralimbic cortex (IL) in the environmental control of appetitive behavior. Inhibition of IL, irrespective of its intrinsic neural activity, attenuates not only the ability of environmental cues predictive of reward availability to promote reward seeking, but also the ability of environmental cues predictive of reward omission to suppress this behavior. Here we report that such bidirectional behavioral modulation in rats is mediated by functionally distinct units of neurons (neural ensembles) that are concurrently localized within the same IL brain area but selectively reactive to different environmental cues.

Naloxone and Metabolites Quantification in Cord Blood of Prenatally Exposed Newborns and Correlations with Maternal Concentrations.

 To quantify naloxone and metabolite concentrations in newborns prenatally exposed to sublingual buprenorphine/naloxone and to correlate neonatal and maternal metabolite concentrations.  This is a prospective observational cohort study. Eleven pregnant women treated for opioid use disorder with sublingual buprenorphine/naloxone were enrolled.

Role of Central Amygdala Neuronal Ensembles in Incubation of Nicotine Craving.

Unlabelled: The craving response to smoking-associated cues in humans or to intravenous nicotine-associated cues in adult rats progressively increases or incubates after withdrawal. Here, we further characterized incubation of nicotine craving in the rat model by determining whether this incubation is observed after adolescent-onset nicotine self-administration. We also used the neuronal activity marker Fos and the Daun02 chemogenetic inactivation procedure to identify cue-activated neuronal ensembles that mediate incubation of nicotine craving.

Distinct Fos-Expressing Neuronal Ensembles in the Ventromedial Prefrontal Cortex Mediate Food Reward and Extinction Memories.

Unlabelled: In operant learning, initial reward-associated memories are thought to be distinct from subsequent extinction-associated memories. Memories formed during operant learning are thought to be stored in "neuronal ensembles." Thus, we hypothesize that different neuronal ensembles encode reward- and extinction-associated memories.

Structural Determinants of Antiretroviral Therapy Use, HIV Care Attendance, and Viral Suppression among Adolescents and Young Adults Living with HIV.

Background: The authors examined associations between structural characteristics and HIV disease management among a geographically diverse sample of behaviorally and perinatally HIV-infected adolescents and young adults in the United States.

Methods: The sample included 1891 adolescents and young adults living with HIV (27.8% perinatally infected; 72.

The nutrient sensor OGT in PVN neurons regulates feeding.

Maintaining energy homeostasis is crucial for the survival and health of organisms. The brain regulates feeding by responding to dietary factors and metabolic signals from peripheral organs. It is unclear how the brain interprets these signals.

11β-hydroxysteroid dehydrogenase inhibition as a new potential therapeutic target for alcohol abuse.

The identification of new and more effective treatments for alcohol abuse remains a priority. Alcohol intake activates glucocorticoids, which have a key role in alcohol's reinforcing properties. Glucocorticoid effects are modulated in part by the activity of 11β-hydroxysteroid dehydrogenases (11β-HSD) acting as pre-receptors.

Regulation of hypothalamic neuropeptides gene expression in diet induced obesity resistant rats: possible targets for obesity prediction?

Several factors play a role in obesity (i.e., behavior, environment, and genetics) and epigenetic regulation of gene expression has emerged as a potential contributor in the susceptibility and development of obesity.