Recently, quantitative metabolomics identified a panel of 10-plasma lipids that were highly predictive of conversion to Alzheimer’s disease (AD) in cognitively normal older individuals (N=28, area-under-the-curve; AUC=0.92, sensitivity/specificity of 90%/90%). We failed to replicate these findings in a substantially larger study from two independent cohorts - the Baltimore Longitudinal Study of Aging (BLSA, N=93, AUC=0.642, sensitivity/specificity of 51.6%/65.7%) and the Age, Gene/Environment Susceptibility-Reykjavik Study (AGES-RS, N=100, AUC=0.395, sensitivity/specificity of 47.0%/36.0%). In analyses applying machine learning methods to all 187 metabolite concentrations assayed, we find a modest signal in the BLSA with distinct metabolites associated with the preclinical and symptomatic stages of AD, whereas the same methods gave poor classification accuracies in the AGES-RS samples. We believe that ours is the largest blood biomarker study of preclinical AD to date. These findings underscore the importance of large-scale independent validation of index findings from biomarker studies with relatively small sample sizes.

Background Hypertensive pregnancy disorders have been associated with subjective cognitive complaints or brain white matter lesions five to ten years after the hypertensive pregnancy. The long-term effects of hypertensive pregnancies on brain structure and cognitive function remain unknown. Methods and Results This study included 1279 women who participated in the Family Blood Pressure Project Genetic Epidemiology Network of Arteriopathy (GENOA) study. As part of the ancillary Genetics of Microangiopathic Brain Injury study, a neurocognitive battery was administered; 1075 also had a brain MRI. A history of a hypertensive pregnancy disorder was obtained by self-report using a validated questionnaire. Linear models fit with generalized estimating equations were used to assess the association between hypertensive pregnancy disorders and cognition, adjusting for age, race, education, body mass index, smoking, current hypertension, hypertension duration, and family history of hypertension. Regression models for the brain MRI outcomes also were adjusted for total intracranial volume. Women with histories of hypertensive pregnancy disorders performed worse on all measures of processing speed: Digital Symbol Substitution Test (mean score 41.2 vs 43.4, P=0.005), Trail Making Test Part A (mean seconds 45.1 vs 42.2, P=0.035), and Stroop (mean score 173.9 vs 181.0, P=0.002) and had smaller brain volumes compared to women with histories of normotensive pregnancies (286 vs 297, P=0.023). Conclusions Hypertensive pregnancy disorders are associated with worse performance on tests of processing speed and smaller brain volumes decades later. Population-based studies are needed to provide critical insight as to the contribution of hypertensive pregnancies to risk of cognitive decline and dementia.

OBJECTIVES Elucidating associations of specific inflammatory biomarkers with cognitive function in African Americans (AA) and European Americans (EA) with prevalent vascular risk factors could identify vascular-mediated effects on cognitive impairment. DESIGN Cross-sectional analysis using Generalized Estimating Equations to account for familial clustering; standardized β-coefficients, adjusted for age, sex, and education are reported. SETTING A community cohort study in Jackson, MS and Rochester, MN. PARTICIPANTS Genetic Epidemiology Network of Arteriopathy (GENOA)-Genetics of Microangiopathic Brain Injury (GMBI) Study. MEASUREMENTS We examined associations between inflammation [high-sensitivity C-reactive protein (CRP), interleukin (IL)-6, soluble tumor necrosis factor receptors 1 and 2 (sTNFR1, sTNFR2)] and cognitive function measures [global (G), processing speed (PS), language (L), memory (M), and executive function (EF)] in AA and EA (N=1965; age 26–95y, 64% women, 52% AA, 75% hypertensive). RESULTS In AA, higher sTNFR2 was associated with poorer cognition across all domains (G: −0.11, p=.009; PS: −0.11, p<.001; L: −0.08, p=.002; M: −0.09, p=.008; EF: −0.07, p=.032); sTNFR1 was associated with poorer PS (−0.08, p<.001) and with EF (−0.08, p=.008); higher CRP was associated with lower PS (−0.04, p=.024), and higher IL6 was associated with poorer EF (−0.07, p=.019). In EA, only higher sTNFR1 was associated with poorer PS (−0.05, p=.007). We did not find support for associations between cognition and sTNFR2, CRP or IL6 in EA. CONCLUSION In a population with heightened vascular risk, adverse associations between inflammation and cognitive function were especially apparent in AA, primarily involving markers of TNFα activity.

We recently showed that Alzheimer's disease patients have lower plasma concentrations of the phosphatidylcholines (PC16:0/20:5; PC16:0/22:6; and PC18:0/22:6) relative to healthy controls. We now extend these findings by examining associations between plasma concentrations of these PCs with cognition and brain function (measured by regional resting state cerebral blood flow; rCBF) in non-demented older individuals. Within the Baltimore Longitudinal Study of Aging neuroimaging substudy, participants underwent cognitive assessments and brain (15)O-water positron emission tomography. Plasma phosphatidylcholines concentrations (PC16:0/20:5, PC16:0/22:6, and PC18:0/22:6), cognition (California Verbal Learning Test (CVLT), Trail Making Test A&B, the Mini-Mental State Examination, Benton Visual Retention, Card Rotation, and Fluencies-Category and Letter), and rCBF were assessed. Lower plasma phosphatidylcholine concentrations were associated with lower baseline memory performance (CVLT long delay recall task-PC16:0/20:5: -2.17-1.39-0.60 p = 0.001 (β with 95% confidence interval subscripts)) and lower rCBF in several brain regions including those associated with memory performance and higher order cognitive processes. Our findings suggest that lower plasma concentrations of PC16:0/20:5, PC16:0/22:6, and PC18:0/22:6 are associated with poorer memory performance as well as widespread decreases in brain function during aging. Dysregulation of peripheral phosphatidylcholine metabolism may therefore be a common feature of both Alzheimer's disease and age-associated differences in cognition.

Background Disease severity is important when considering genes for inclusion on reproductive expanded carrier screening (ECS) panels. We applied a validated and previously published algorithm that classifies diseases into four severity categories (mild, moderate, severe, and profound) to 176 genes screened by ECS. Disease traits defining severity categories in the algorithm were then mapped to four severity‐related ECS panel design criteria cited by the American College of Obstetricians and Gynecologists (ACOG). Methods Eight genetic counselors (GCs) and four medical geneticists (MDs) applied the severity algorithm to subsets of 176 genes. MDs and GCs then determined by group consensus how each of these disease traits mapped to ACOG severity criteria, enabling determination of the number of ACOG severity criteria met by each gene. Results Upon consensus GC and MD application of the severity algorithm, 68 (39%) genes were classified as profound, 71 (40%) as severe, 36 (20%) as moderate, and one (1%) as mild. After mapping of disease traits to ACOG severity criteria, 170 out of 176 genes (96.6%) were found to meet at least one of the four criteria, 129 genes (73.3%) met at least two, 73 genes (41.5%) met at least three, and 17 genes (9.7%) met all four. Conclusion This study classified the severity of a large set of Mendelian genes by collaborative clinical expert application of a trait‐based algorithm. Further, it operationalized difficult to interpret ACOG severity criteria via mapping of disease traits, thereby promoting consistency of ACOG criteria interpretation.

Cadherins constitute a family of transmembrane proteins that mediate calcium-dependent cell-cell adhesion. The extracellular domain of cadherins consists of extracellular cadherin (EC) domains, separated by calcium binding sites. The EC interacts with other cadherin molecules in cis and in trans to mechanically hold apposing cell surfaces together. CDH2 encodes N-cadherin, whose essential roles in neural development include neuronal migration and axon pathfinding. However, CDH2 has not yet been linked to a Mendelian neurodevelopmental disorder. Here, we report de novo heterozygous pathogenic variants (seven missense, two frameshift) in CDH2 in nine individuals with a syndromic neurodevelopmental disorder characterized by global developmental delay and/or intellectual disability, variable axon pathfinding defects (corpus callosum agenesis or hypoplasia, mirror movements, Duane anomaly), and ocular, cardiac, and genital anomalies. All seven missense variants (c.1057G>A [p.Asp353Asn]; c.1789G>A [p.Asp597Asn]; c.1789G>T [p.Asp597Tyr]; c.1802A>C [p.Asn601Thr]; c.1839C>G [p.Cys613Trp]; c.1880A>G [p.Asp627Gly]; c.2027A>G [p.Tyr676Cys]) result in substitution of highly conserved residues, and six of seven cluster within EC domains 4 and 5. Four of the substitutions affect the calcium-binding site in the EC4-EC5 interdomain. We show that cells expressing these variants in the EC4-EC5 domains have a defect in cell-cell adhesion; this defect includes impaired binding in trans with N-cadherin-WT expressed on apposing cells. The two frameshift variants (c.2563_2564delCT [p.Leu855Valfs*4]; c.2564_2567dupTGTT [p.Leu856Phefs*5]) are predicted to lead to a truncated cytoplasmic domain. Our study demonstrates that de novo heterozygous variants in CDH2 impair the adhesive activity of N-cadherin, resulting in a multisystemic developmental disorder, that could be named ACOG syndrome (agenesis of corpus callosum, axon pathfinding, cardiac, ocular, and genital defects).

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Summary A patient with secondary syphilis presenting with jaundice is reported. Hepatic histology showed evidence of non-specific granuloma and active hepatitis but no cholestasis. This has been treated successfully with antisyphilitic therapy. The possibility of syphilitic pancreatitis and diabetes mellitus is discussed. The importance of serological tests for syphilis in jaundice of obscure origin is emphasized.