The transcriptomic and spatial organization of telencephalic GABAergic neuronal types.

The telencephalon of the mammalian brain comprises multiple regions and circuit pathways that play adaptive and integrative roles in a variety of brain functions. There is a wide array of GABAergic neurons in the telencephalon; they play a multitude of circuit functions, and dysfunction of these neurons has been implicated in diverse brain disorders. In this study, we conducted a systematic and in-depth analysis of the transcriptomic and spatial organization of GABAergic neuronal types in all regions of the mouse telencephalon and their developmental origins. This was accomplished by utilizing 611,423 single-cell transcriptomes from the comprehensive and high-resolution transcriptomic and spatial cell type atlas for the adult whole mouse brain we have generated, supplemented with an additional single-cell RNA-sequencing dataset containing 99,438 high-quality single-cell transcriptomes collected from the pre- and postnatal developing mouse brain. We present a hierarchically organized adult telencephalic GABAergic neuronal cell type taxonomy of 7 classes, 52 subclasses, 284 supertypes, and 1,051 clusters, as well as a corresponding developmental taxonomy of 450 clusters across different ages. Detailed charting efforts reveal extraordinary complexity where relationships among cell types reflect both spatial locations and developmental origins. Transcriptomically and developmentally related cell types can often be found in distant and diverse brain regions indicating that long-distance migration and dispersion is a common characteristic of nearly all classes of telencephalic GABAergic neurons. Additionally, we find various spatial dimensions of both discrete and continuous variations among related cell types that are correlated with gene expression gradients. Lastly, we find that cortical, striatal and some pallidal GABAergic neurons undergo extensive postnatal diversification, whereas septal and most pallidal GABAergic neuronal types emerge simultaneously during the embryonic stage with limited postnatal diversification. Overall, the telencephalic GABAergic cell type taxonomy can serve as a foundational reference for molecular, structural and functional studies of cell types and circuits by the entire community.

Trends in HIV preexposure prophylaxis utilization and spending among individuals with commercial insurance.

In a cross-sectional analysis of HIV preexposure prophylaxis (PrEP) utilization by commercially insured patients from 2019 to 2021, most prescriptions were for branded formulations of PrEP despite the availability of a generic version. Accounting for the modest relative clinical benefit of branded TAF/FTC (tenofovir alafenamide fumarate/emtricitabine) PrEP over generic TDF/FTC (tenofovir disoproxil fumarate/emtricitabine) PrEP, use of generic TDF/FTC PrEP would have reduced commercial insurers' spending by 33%.

Medicare Part B Spending on Macular Degeneration Treatments Associated With Manufacturer Payments to Ophthalmologists.

Importance: Age-related macular degeneration (ARMD) therapies aflibercept and ranibizumab are among the highest-cost Medicare Part B drugs, even though off-label use of lower-cost bevacizumab is clinically noninferior. Payments from manufacturers of these ARMD therapies to ophthalmologists are hypothesized to be factors in ophthalmologists' therapeutic choice, controlling for ophthalmologist and patient characteristics. Objective: To assess the association between manufacturer payments to ophthalmologists and choice of ARMD treatment as well as to identify ophthalmologist-level characteristics associated with prescribing lower-cost ARMD therapies. Design, Setting, and Participants: This retrospective cross-sectional study of longitudinal (2013-2019) Medicare Part B data was conducted from December 2021 to December 2022. Ophthalmologists prescribing aflibercept (manufactured by Regeneron Pharmaceuticals Inc), rabinizumab, or bevacizumab (both manufactured by Genentech Inc) for ARMD treatment of Medicare Part B beneficiaries were included. Data on manufacturer payments to ophthalmologists were obtained from the Open Payments database. Main Outcomes and Measures: The primary outcome was the percentage of bevacizumab prescribed by ophthalmologists among all ARMD therapies. Regression analysis assessed variation in bevacizumab prescribing by acceptance of manufacturer payments as well as by ophthalmologist and patient characteristics. Ophthalmologist characteristics were duration of practice and Medicare Administrative Contractor region, and patient characteristics were aggregated at the ophthalmologist level and included mean beneficiary age, percentage of dual-eligible beneficiaries, mean beneficiary risk score, and percentage of White beneficiaries. Savings were estimated by projecting the change in bevacizumab use had ophthalmologists not accepted manufacturer payments, controlling for all ophthalmologist and patient characteristics and comparing with observed use and costs. Results: A total of 21 584 ophthalmologists (18 489 males [85.7%]) were included. Ophthalmologists who accepted manufacturer payments were significantly less likely to prescribe bevacizumab (28.0% [95% CI, 24.6%-42.5%] of patients) compared with those who did not accept manufacturer payments (45.8% [95% CI, 44.5%-47.1%]). Ophthalmologists who saw dual-eligible beneficiaries had greater bevacizumab prescribing (50.0% [95% CI, 40.6%-68.3%] in the highest quartile vs 36.1% [95% CI, 33.5%-38.8%] in the lowest quartile; ß coefficient, 0.139; P < .001), while those who saw patients with higher mean beneficiary risk scores had lower bevacizumab use (38.0% [95% CI, 23.7%-44.1%] in the highest quartile vs 48.2% [95% CI, 45.5%-50.8%] in the lowest quartile; ß coefficient, -0.102, P < .001). Had ophthalmologists who accepted manufacturer payments prescribed ARMD drugs as those who did not accept payments, Medicare spending on these treatments would have been $642 779 703.08 lower from 2013 to 2019, a 2.0% savings. Conclusions and Relevance: Results of this cross-sectional study suggest that drug manufacturer payments to ophthalmologists were associated with selection of higher-cost therapies for ARMD, which is a factor in increased Medicare and patient spending. Development of manufacturer payment models that encourage ophthalmologists to choose lower-cost therapies are needed.

Comparison of Generic Prescribing Patterns Among 340B-Eligible and Non-340B Prescribers in the Medicare Part D Program.

This cross-sectional study examines generic prescribing patterns for 2020 among 340B-eligible and non-340B clinicians in the Medicare Part D program to assess whether 340B revenue incentives may influence prescribing.

Environmental heterogeneity mediates scale-dependent declines in kelp diversity on intertidal rocky shores.

Biodiversity loss is driven by interacting factors operating at different spatial scales. Yet, there remains uncertainty as to how fine-scale environmental conditions mediate biological responses to broad-scale stressors. We surveyed intertidal rocky shore kelp beds situated across a local gradient of wave action and evaluated changes in kelp diversity and abundance after more than two decades of broad scale stressors, most notably the 2013-2016 heat wave. Across all sites, species were less abundant on average in 2017 and 2018 than during 1993-1995 but changes in kelp diversity were dependent on wave exposure, with wave exposed habitats remaining stable and wave sheltered habitats experiencing near complete losses of kelp diversity. In this way, wave exposed sites have acted as refugia, maintaining regional kelp diversity despite widespread local declines. Fucoids, seagrasses and two stress-tolerant kelp species (Saccharina sessilis, Egregia menziesii) did not decline as observed in other kelps, and the invasive species Sargassum muticum increased significantly at wave sheltered sites. Long-term monitoring data from a centrally-located moderate site suggest that kelp communities were negatively impacted by the recent heatwave which may have driven observed losses throughout the region. Wave-sheltered shores, which saw the largest declines, are a very common habitat type in the Northeast Pacific and may be especially sensitive to losses in kelp diversity and abundance, with potential consequences for coastal productivity. Our findings highlight the importance of fine-scale environmental heterogeneity in mediating biological responses and demonstrate how incorporating differences between habitat patches can be essential to capturing scale-dependent biodiversity loss across the landscape.