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L-3,4-dihydroxyphenylalanine (L-DOPA) remains the main treatment for motor symptoms of Parkinson's disease (PD). However, chronic use is associated with the development of complications such as L-DOPA-induced dyskinesia. We previously demonstrated that LY-487,379, a highly selective metabotropic glutamate receptor 2 (mGluR2) positive allosteric modulator (PAM), reduces the severity of L-DOPA-induced abnormal involuntary movements (AIMs) in the 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD, without interfering with the anti-parkinsonian action of L-DOPA. Here, we seek to determine the effect of AZD8529, another highly selective mGluR2 PAM, on L-DOPA-induced AIMs in the 6-OHDA-lesioned rat. Unlike LY-487,379, AZD8529 has previously undergone clinical trials and could therefore be repurposed if proven efficacious in pre-clinical studies. We first determined the pharmacokinetic (PK) profile of AZD8529 to administer doses leading to clinically relevant plasma levels in the behavioural studies. Then, dyskinetic 6-OHDAlesioned rats were administered AZD8529 (0.1, 0.3, and 1 mg/kg) or vehicle in combination with L-DOPA followed by assessment of AIMs severity. The cylinder test was then used to evaluate the effect of AZD8529 on the anti-parkinsonian action of L-DOPA. We found that AZD8529 (0.1, 0.3 and 1 mg/kg) in combination with L-DOPA significantly reduced the severity of AIMs duration (P < 0.05), but not amplitude, when compared to L-DOPA/vehicle. AZD8529 administration did not interfere with L-DOPA anti-parkinsonian action. Our results provide evidence that mGluR2 positive allosteric modulation with AZD8529 may be a viable, yet relatively modest, treatment strategy to alleviate L-DOPA-induced., Competing Interests: Declarations. Ethics approval: This study was approved by the ethics committee of McGill University and the Montreal Neurological Institute-Hospital (The Neuro, Animal Use Protocol 2017–7922) in accordance with the regulations defined by the Canadian Council on Animal Care. Consent to participate: Not applicable. Consent to publish: Not applicable. Competing interest: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Context: Area-level predictive models are commonly used to screen children for blood lead levels (BLLs) greater than the Center for Disease Control and Prevention (CDC) blood lead reference value (BLRV) of 3.5 µg/dL., Objectives: To increase screening accuracy and precision by creating a parcel-level model incorporating housing characteristics to predict parcels where children are at high risk., Design: Residential addresses associated with child blood lead tests were linked to neighborhood- and parcel-level characteristics and proximity to lead sources. Regression forests were fit using different predictor combinations and compared using cross-validated accuracy and decile-based agreement across all residential parcels., Setting: Hamilton County, Ohio, United States., Participants: Children less than 6 years of age with blood lead tests between January 2020 and April 2023., Main Outcome Measure: Cross-validated model accuracy and decile-based agreement across residential parcels., Results: 27,782 tests were matched to a residential parcel. Regression forests using Parcel + Source (70.8% AUC) and Neighborhood + Parcel + Source predictors (70.3% AUC) had the highest cross-validated accuracy for predicting BLLs >3.5 µg/dL. Parcel-level predictions revealed heterogeneity of risk across parcels within the same tract., Conclusions: Parcel characteristics improved the accuracy of predicting locations of children with BLLs >3.5 µg/dL and can help identify children at high risk living in low-risk areas. A parcel-level identification of housing-based lead hazards could guide and support action to prevent pediatric lead exposure., (Copyright © 2025 Wolters Kluwer Health, Inc. All rights reserved.)