19 research outputs found

    High-throughput assay for determining enantiomeric excess of chiral diols, amino alcohols, and amines and for direct asymmetric reaction screening

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    Determining enantiomeric excess (e.e.) in chiral compounds is key to development of chiral catalyst auxiliaries and chiral drugs. Here we describe a sensitive and robust fluorescence-based assay for determining e.e. in mixtures of enantiomers of 1,2- and 1,3-diols, chiral amines, amino alcohols, and amino-acid esters. The method is based on dynamic self-assembly of commercially available chiral amines, 2-formylphenylboronic acid, and chiral diols in acetonitrile to form fluorescent diastereomeric complexes. Each analyte enantiomer engenders a diastereomer with distinct fluorescence wavelength/intensity originating from enantiopure fluorescent ligands. In this assay, enantiomers of amines and amine derivatives assemble with diol-type ligands containing a binaphthol moiety (BINOL and VANOL), whereas diol enantiomers form complexes with the enantiopure amine-type fluorescent ligand tryptophanol. The differential fluorescence is utilized to determine the amount of each enantiomer in the mixture with an error of &lt;1% e.e. This method enables high-throughput real-time evaluation of enantiomeric/diastereomeric excess (e.e./d.e.) and product yield of crude asymmetric reaction products. The procedure comprises high-throughput liquid dispensing of three components into 384-well plates and recording of fluorescence using an automated plate reader. The approach enables scaling up the screening of combinatorial libraries and, together with parallel synthesis, creates a robust platform for discovering chiral catalysts or auxiliaries for asymmetric transformations and chiral drug development. The procedure takes ~4–6 h and requires 10–20 ng of substrate per well. Our fluorescence-based assay offers distinct advantages over existing methods because it is not sensitive to the presence of common additives/impurities or unreacted/incompletely utilized reagents or catalysts.</p

    Reproductive constraints influence habitat accessibility, segregation, and preference of sympatric albatross species

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    Transdiagnostic neurocognitive subgroups and functional course in young people with emerging mental disorders: a cohort study.

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    BACKGROUND: Neurocognitive impairments robustly predict functional outcome. However, heterogeneity in neurocognition is common within diagnostic groups, and data-driven analyses reveal homogeneous neurocognitive subgroups cutting across diagnostic boundaries. AIMS: To determine whether data-driven neurocognitive subgroups of young people with emerging mental disorders are associated with 3-year functional course. METHOD: Model-based cluster analysis was applied to neurocognitive test scores across nine domains from 629 young people accessing mental health clinics. Cluster groups were compared on demographic, clinical and substance-use measures. Mixed-effects models explored associations between cluster-group membership and socio-occupational functioning (using the Social and Occupational Functioning Assessment Scale) over 3 years, adjusted for gender, premorbid IQ, level of education, depressive, positive, negative and manic symptoms, and diagnosis of a primary psychotic disorder. RESULTS: Cluster analysis of neurocognitive test scores derived three subgroups described as 'normal range' (n = 243, 38.6%), 'intermediate impairment' (n = 252, 40.1%), and 'global impairment' (n = 134, 21.3%). The major mental disorder categories (depressive, anxiety, bipolar, psychotic and other) were represented in each neurocognitive subgroup. The global impairment subgroup had lower functioning for 3 years of follow-up; however, neither the global impairment (B = 0.26, 95% CI -0.67 to 1.20; P = 0.581) or intermediate impairment (B = 0.46, 95% CI -0.26 to 1.19; P = 0.211) subgroups differed from the normal range subgroup in their rate of change in functioning over time. CONCLUSIONS: Neurocognitive impairment may follow a continuum of severity across the major syndrome-based mental disorders, with data-driven neurocognitive subgroups predictive of functional course. Of note, the global impairment subgroup had longstanding functional impairment despite continuing engagement with clinical services

    The genetic relationship between educational attainment and cognitive performance in major psychiatric disorders

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    Cognitive deficits are a core feature of psychiatric disorders like schizophrenia and bipolar disorder. Evidence supports a genome-wide polygenic score (GPS) for educational attainment (GPSEDU) can be used to explain variability in cognitive performance. We aimed to identify different cognitive domains associated with GPSEDU in a transdiagnostic clinical cohort of chronic psychiatric patients with known cognitive deficits. Bipolar and schizophrenia patients from the PsyCourse cohort (N = 730; 43% female) were used. Likewise, we tested whether GPSs for schizophrenia (GPSSZ) and bipolar disorder (GPSBD) were associated with cognitive outcomes. GPSEDU explained 1.5% of variance in the backward verbal digit span, 1.9% in the number of correctly recalled words of the Verbal Learning and Memory Test, and 1.1% in crystallized intelligence. These effects were robust to the influences of treatment and diagnosis. No significant associations between GPSSZ or GPSBD with cognitive outcomes were found. Furthermore, these risk scores did not confound the effect of GPSEDU on cognitive outcomes. GPSEDU explains a small fraction of cognitive performance in adults with psychiatric disorders, specifically for domains related to linguistic learning and working memory. Investigating such a proxy-phenotype longitudinally, could give intriguing insight into the disease course, highlighting at what time genes play a more influential role on cognitive performance. Better understanding the origin of these deficits might help identify those patients at risk for lower levels of functioning and poor social outcomes. Polygenic estimates may in the future be part of predictive models for more personalized interventions.peerReviewe
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