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Although selective serotonin reuptake inhibitors are commonly prescribed for prenatal depression, there exists controversy over adverse effects of SSRI use on fetal development. Few studies have adequately isolated outcomes due to SSRI exposure and those due to maternal psychiatric conditions. Here, we directly investigated outcomes of exposure to widely-used SSRIs Fluoxetine and Citalopram on the developing nervous system of Xenopus laevis tadpoles, using an integrative experimental approach. We exposed tadpoles to low doses of Citalopram and Fluoxetine during a critical developmental period and found that different experimental groups displayed opposing behavioral effects. While both groups showed reduced schooling behavior, the Fluoxetine group showed increased seizure susceptibility and reduced startle habituation. In contrast, Citalopram treated tadpoles had decreased seizure susceptibility and increased habituation. Both groups had abnormal dendritic morphology in the optic tectum, a brain area important for behaviors tested. Whole-cell electrophysiological recordings of tectal neurons showed no differences in synaptic function; however, tectal cells from Fluoxetine-treated tadpoles had decreased voltage gated K+ currents while cells in the Citalopram group had increased K+ currents. Both behavioral and electrophysiological findings indicate that cells and circuits in the Fluoxetine treated optic tecta are hyperexcitable, while the Citalopram group exhibits decreased excitability. Taken together, these results show that early developmental exposure to SSRIs is sufficient to induce neurodevelopmental effects, however these effects can be complex and vary depending on the SSRI. This may explain some discrepancies across human studies, and further underscores the importance of serotonergic signaling for the developing nervous system. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinase-9 (MMP-9) is a secreted endopeptidase targeting extracellular matrix proteins, creating permissive environments for neuronal development and plasticity. Developmental dysregulation of MMP-9 may also lead to neurodevelopmental disorders (ND). Here, we test the hypothesis that chronically elevated MMP-9 activity during early neurodevelopment is responsible for neural circuit hyperconnectivity observed in Xenopus tadpoles after early exposure to valproic acid (VPA), a known teratogen associated with ND in humans. In Xenopus tadpoles, VPA exposure results in excess local synaptic connectivity, disrupted social behavior and increased seizure susceptibility. We found that overexpressing MMP-9 in the brain copies effects of VPA on synaptic connectivity, and blocking MMP-9 activity pharmacologically or genetically reverses effects of VPA on physiology and behavior. We further show that during normal neurodevelopment MMP-9 levels are tightly regulated by neuronal activity and required for structural plasticity. These studies show a critical role for MMP-9 in both normal and abnormal development. [ABSTRACT FROM AUTHOR]

Objective: To assess the effects of delirium on the institutionalization rate, taking into account geriatric syndromes and nutritional status.Methods: This population-based study took place in an acute care unit and included participants older than 75 years, arriving from home and later discharged. Confusion Assessment Method (CAM) symptoms were recorded by the nurses within 24 hours after admission and every 3 days. Delirium was defined using the CAM algorithm, and subsyndromal delirium responded to symptoms not fulfilling the CAM algorithm. These delirium categories were either present at admission (prevalent) or occurred during the hospital stay (incident). Participants were classified as having a low dietary intake when energy intake was at any time lower than 600 kcal/d. Age, sex, known cognitive impairment, weight, functional dependency, and laboratory testing as well as diagnoses were also recorded. Step-by-step backward logistic regression was used to identify predictors of institutionalization.Results: Among 427 patients, 310 (72.6%) were discharged and were compared with 117 (27.4%) participants admitted to an institution. Female sex (odds ratio [OR]: OR 2.15, 95% confidence interval [CI]: CI 1.22-3.78), prevalent delirium (OR 3.19, 95% CI 1.33-7.64), subsyndromal delirium (OR 2.72, 95% CI 1.48-5.01), incident subsyndromal delirium (OR 4.27, 95% CI 2.17-8.39), low dietary intake (OR 2.50, 95% CI 1.35-4.63), and a fall (OR 2.16, 95% CI 1.22-3.84) or a diagnosis of stroke (OR 2.03, 95% CI 1.04-3.94) were independent predictors of institutionalization.Conclusions: Symptoms of delirium and severe nutritional impairment led patients to geriatric institutions. Therefore, these institutions need to implement policies that address both of these issues. [ABSTRACT FROM AUTHOR]