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Summary: Background: Perivascular spaces (PVS) on brain MRI are surrogates for small parenchymal blood vessels and their perivascular compartment, and may relate to brain health. However, it is unknown whether PVS can predict dementia risk and brain atrophy trajectories in participants without dementia, as longitudinal studies on PVS are scarce and current methods for PVS assessment lack robustness and inter-scanner reproducibility. Methods: We developed a robust algorithm to automatically assess PVS count and size on clinical MRI, and investigated 1) their relationship with dementia risk and brain atrophy in participants without dementia, 2) their longitudinal evolution, and 3) their potential use as a screening tool in simulated clinical trials. We analysed 46,478 clinical measurements of cognitive functioning and 20,845 brain MRI scans from 10,004 participants (71.1 ± 9.7 years-old, 56.6% women) from three publicly available observational studies on ageing and dementia (the Alzheimer’s Disease Neuroimaging Initiative, the National Alzheimer’s Coordinating Centre database, and the Open Access Series of Imaging Studies). Clinical and MRI data collected between 2004 and 2022 were analysed with consistent methods, controlling for confounding factors, and combined using mixed-effects models. Findings: Our fully-automated method for PVS assessment showed excellent inter-scanner reproducibility (intraclass correlation coefficients >0.8). Fewer PVS and larger PVS diameter at baseline predicted higher dementia risk and accelerated brain atrophy. Longitudinal trajectories of PVS markers differed significantly in participants without dementia who converted to dementia compared with non-converters. In simulated placebo-controlled trials for treatments targeting cognitive decline, screening out participants at low risk of dementia based on our PVS markers enhanced the power of the trial independently of Alzheimer’s disease biomarkers. Interpretation: These robust cerebrovascular markers predict dementia risk and brain atrophy and may improve risk-stratification of patients, potentially reducing cost and increasing throughput of clinical trials to combat dementia. Funding: US National Institutes of Health.

Greenhouse vegetable production in Canadian Prairies is important for creating a sustainable regional food economy, especially in northern communities. This study included the estimation of heating demand for year-round production and evaluation of the economic feasibility of greenhouse vegetable production (tomato, cucumber, and pepper) in a conceptually designed greenhouse (0.6 ha) located in remote northern communities in Saskatchewan, Canada. The heating simulation was based on a greenhouse heating simulation model (GREENHEAT) developed by the authors recently. The simulation results showed that the annual heating requirement for the production of tomato, cucumber, and pepper are 1486 MJ m−2, 1657 MJ m−2, and 1754 MJ m−2, respectively. The economic analysis indicates the net return (NR) from the production of tomato, cucumber, and pepper, are C$69.2/m2 (in Canadian dollar, CAD), C$41.5/m2, and C$43.8/m2, respectively, based on the market price C$3.5/kg, C$2.7/kg, and C$8.0/kg, and yields of 55.0 kg m−2, 65.0 kg m−2, and 23.0 kg m−2. The net present value (NPV) for the tomato, cucumber, and pepper production are C$1.9 M, C$1.2 M, and C$1.1 M, respectively, and the benefit-cost ratio (BCR) are 1.38, 1.21, and 1.21. The economic feasibility analysis indicates the year-round production of vegetables in a greenhouse at remote northern Saskatchewan would be economically profitable. Keywords: Northern latitudes, Heating requirement, Economic analysis, Sensitivity analysis, Year-round production

Purpose: In parent-child trios with genome sequencing data, we investigated inherited biallelic deletions to identify known and novel genetic disorders. Methods: We developed a copy-number variations analysis pipeline based on autosomal genome sequencing read depth of Genomics England 100,000 Genomes Project data from 11,754 parent-child trios and additional 18,875 non-trios. A control cohort of 15,440 cancer patients provided independent deletion frequencies. Results: Autosomal recessive (AR) modeling detected 34 distinct rare deletions that were homozygous in the proband and heterozygous in both parents. These inherited biallelic deletions were only detected in 52 trios. These “knockout” regions included 37 genes, having among them 8 with an Online Mendelian Inheritance in Man AR annotation. Deletions of NPHP1, followed by OTOA, both within segmental duplications, were the only recurrent findings explaining phenotypes in a total of 10 and 3 patients, respectively. Recurrent heterozygous NPHP1 deletions were detected in 0.3%-0.5% of controls. We reviewed “knockout” patients for the remaining 29 genes without disease associations and identified SLC66A1 as a likely novel cause for AR rod-cone dystrophy in 4 families. Conclusion: A tailored copy-number variations analysis of genome sequencing trio data shows that biallelic inherited gene deletions are rare, with NPHP1 biallelic deletions causing nephronophthisis the leading finding. We propose SLC66A1 as a novel cause for AR retinopathy.

Purpose: Genome sequencing (GS) for diagnosis of rare genetic disease is being introduced into the clinic, but the complexity of the data poses challenges for developing pipelines with high diagnostic sensitivity. We evaluated the performance of the Genomics England 100,000 Genomes Project (100kGP) panel-based pipelines, using craniosynostosis as a test disease., Methods: GS data from 114 probands with craniosynostosis and their relatives (314 samples), negative on routine genetic testing, were scrutinized by a specialized research team, and diagnoses compared with those made by 100kGP., Results: Sixteen likely pathogenic/pathogenic variants were identified by 100kGP. Eighteen additional likely pathogenic/pathogenic variants were identified by the research team, indicating that for craniosynostosis, 100kGP panels had a diagnostic sensitivity of only 47%. Measures that could have augmented diagnoses were improved calling of existing panel genes (+18% sensitivity), review of updated panels (+12%), comprehensive analysis of de novo small variants (+29%), and copy-number/structural variants (+9%). Recent NHS England recommendations that partially incorporate these measures should achieve 85% overall sensitivity (+38%)., Conclusion: GS identified likely pathogenic/pathogenic variants in 29.8% of previously undiagnosed patients with craniosynostosis. This demonstrates the value of research analysis and the importance of continually improving algorithms to maximize the potential of clinical GS., (© 2021. The Author(s).)