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Abstract: Addictive drugs and psychologic stress influence the input strength of ventral tegmental area (VTA) neurons, which implies the involvement of synaptic plasticity in dopaminergic neurons. Properties of excitatory synaptic transmission to the dopaminergic neurons have been analyzed using intracellular and patch-clamp recording methods. In the present study, we attempted to establish the field recording procedure in VTA slice preparations to monitor excitatory synaptic transmission. We evaluated this procedure using slice preparations from 6-hydroxydopamine (6-OHDA)-treated animals. In horizontal slices containing the VTA, electrical stimulation of anterior afferent fibers produced two distinct negative field potentials, presumably a fiber volley component and a transsynaptic component. Pharmacological analysis revealed that the transsynaptic component was composed of bicuculline-sensitive and CNQX-sensitive components. Neonatal 6-OHDA administration reduced approximately 90% of tyrosine hydroxylase expression in the VTA and eliminated more than 50% of the transsynaptic components. This result suggests that at least 50% of the observed transsynaptic component reflected the postsynaptic responses of the dopaminergic neurons. [Copyright &y& Elsevier]

Background: Deficits in speech and emotion perception are intertwined with psychiatric symptoms. How the happy prosody embedded in speech affects target speech-in-noise recognition (TSR) and relates to psychiatric symptoms in patients with schizophrenia (SCHs) remains unclear. This study examined spontaneous brain activity underlying happy TSR and its association with psychiatric symptom dimensions in SCHs., Methods: Fifty-four SCHs and 59 healthy control participants (HCs) underwent the TSR task, Positive and Negative Syndrome Scale (PANSS) assessment, and magnetic resonance imaging scanning. Multivariate analyses of partial least squares (PLS) regression were used to explore the associations between whole-brain fractional amplitude of low-frequency fluctuations (fALFF), happy-neutral TSR (target pseudo-sentences were uttered in happy and neutral prosodies), and five PANSS factor scores (excitement/hostility, depression/anxiety, cognition, positive, and negative)., Results: The happy prosody did not alter TSR or TSR changing rates in either SCHs or HCs. SCHs exhibited lower happy and neutral TSR than HCs. A fALFF PLS component (including precentral/postcentral gyrus, Subcallosal Cortex, several temporal regions, and cerebellum) was associated with happy and neutral TSR. SCHs demonstrated higher PLS fALFF scores and PLS TSR scores than HCs. In SCHs, PLS fALFF scores were correlated with the PANSS positive factor score, and PLS TSR scores were correlated with the PANSS cognition factor score., Conclusions: The positive-psychiatric-symptoms-related spontaneous activity profile was associated with happy and neutral TSR, contributing to the cognition psychiatric symptoms dimension. The findings suggest the potential to improve positive and cognitive symptoms by enhancing happy and neutral TSR in schizophrenia based on neuroplasticity., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: To test the feasibility of a peer-driven behavioral intervention and to evaluate efficacy in reducing HIV-related risk among men who have sex with men (MSM) in China., Methods: Twelve seeds were recruited from traditional MSM venues and a total of 218 MSM were enrolled into 12 intervention groups participating in 4 intervention sessions. The intervention was conducted from May to October 2006 in Anhui Province. Reported condom use and HIV testing were used as outcome indicator to evaluate effectiveness of intervention., Results: Average age was 25.5 years old, 64.2% reported homosexual orientation, and 22.5% bisexual orientation. 77.9% of participants were followed up 3 months after intervention completion. Self-reported condom use measured as use in last 3 episodes of anal intercourse with another man increased from 55.3% at baseline to 65.2% postintervention, whereas HIV testing increased from 10.0% at baseline to 52.4% postintervention. No significant reduction in the number of male sexual partners occurred; however, number of female sexual partners decreased significantly., Conclusions: Interventions are effective in increasing condom use and HIV testing but not in reducing the number of sexual partners. Expansion of such intervention needs to be further explored.

Consistent with the hypothesis that neuroinflammatory processes contribute to the neuropathology of schizophrenia, the protein levels of epidermal growth factor (EGF) and its receptor ErbB1 are abnormal in patients with schizophrenia. To evaluate neuropathological significance of this abnormality, we established an animal model for behavioral deficits by administering EGF into the striatum and evaluated the effects of cyclooxygenase-2 (Cox-2) inhibitor celecoxib. Intracranial infusion of EGF into the striatum of adult male rats activated ErbB1 and induced neurobehavioral impairments observed in several schizophrenia models. Unilateral EGF infusion to the striatum lowered prepulse inhibition (PPI) in a dose-dependent manner and impaired latent learning of active shock avoidance without affecting basal learning ability. Bilateral EGF infusion similarly affected PPI. In contrast, EGF infusion to the nucleus accumbens did not induce a behavioral deficit. Intrastriatal EGF infusion also increased Cox-2 expression, elevated tyrosine hydroxylase activity, and upregulated the levels of dopamine and its metabolites. Subchronic administration of celecoxib (10 mg/kg, p.o.) ameliorated the abnormalities in PPI and latent learning as well as normalized dopamine metabolism. We conclude that this EGF-triggered neuroinflammatory process is mediated in part by Cox-2 activity and perturbs dopamine metabolism to generate neurobehavioral abnormalities.