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Introduction: Analysis of blood for the evaluation of clinically relevant biomarkers requires precise collection and sample handling by phlebotomists and laboratory staff. An important consideration for the clinical application of metabolomics are the different anticoagulants utilized for sample collection. Most studies that have characterized differences in metabolite levels in various blood collection tubes have focused on single analytes. We define analyte levels on a global metabolomics platform following blood sampling using five different, but commonly used, clinical laboratory blood collection tubes (i.e., plasma anticoagulated with either EDTA, lithium heparin or sodium citrate, along with no additive (serum), and EDTA anticoagulated whole blood)., Methods: Using an untargeted metabolomics platform we analyzed five sample types after all had been collected and stored at -80°C. The biochemical composition was determined and differences between the samples established using matched-pair t-tests., Results: We identified 1,117 biochemicals across all samples and detected a mean of 1,036 in the sample groups. Compared to the levels of metabolites in EDTA plasma, the number of biochemicals present at statistically significant different levels (p<0.05) ranged from 452 (serum) to 917 (whole blood). Several metabolites linked to screening assays for rare diseases including acylcarnitines, bilirubin and heme metabolites, nucleosides, and redox balance metabolites varied significantly across the sample collection types., Conclusions: Our study highlights the widespread effects and importance of using consistent additives for assessing small molecule levels in clinical metabolomics. The biochemistry that occurs during the blood collection process creates a reproducible signal that can identify specimens collected with different anticoagulants in metabolomic studies., Impact Statement: In this manuscript, normal/healthy donors had peripheral blood collected using multiple anticoagulants as well as serum during a fasted blood draw. Global metabolomics is a new technology being utilized to draw clinical conclusions and we interrogated the effects of different anticoagulants on the levels of biochemicals from each of the donors. Characterizing the effects of the anticoagulants on biochemical levels will help researchers leverage the information using global metabolomics in order to make conclusions regarding important disease biomarkers., Competing Interests: AK, LF, BW, JC, JW, MM, AE, DT are employees of Metabolon, Inc. and, as such, have affiliations with or financial involvement with Metabolon, Inc. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Introduction: The Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD) Prognostic and Natural History Study (PNHS) aims at understanding the role of amyloid imaging in the earliest stages of Alzheimer's disease (AD). AMYPAD PNHS adds (semi-)quantitative amyloid PET imaging to several European parent cohorts (PCs) to predict AD-related progression as well as address methodological challenges in amyloid PET., Methods: AMYPAD PNHS is an open-label, prospective, multi-center, cohort study recruiting from multiple PCs. Around 2000 participants will undergo baseline amyloid positron emission tomography (PET), half of whom will be invited for a follow-up PET 12 at least 12 months later., Results: Primary include several amyloid PET measurements (Centiloid, SUVr, BP ND , R 1 ), and secondary are their changes from baseline, relationship to other amyloid markers (cerebrospinal fluid and visual assessment), and predictive value of AD-related decline., Expected Impact: Determining the role of amyloid PET for the understanding of this complex disease and potentially improving secondary prevention trials., (© 2020 The Authors. Alzheimer's & Dementia published by Wiley Periodicals, Inc. on behalf of Alzheimer's Association.)

Background: The application of whole-exome sequencing for the diagnosis of genetic disease has paved the way for systems-based approaches in the clinical laboratory. Here, we describe a clinical metabolomics method for the screening of metabolic diseases through the analysis of a multi-pronged mass spectrometry platform. By simultaneously measuring hundreds of metabolites in a single sample, clinical metabolomics offers a comprehensive approach to identify metabolic perturbations across multiple biochemical pathways., Methods: We conducted a single- and multi-day precision study on hundreds of metabolites in human plasma on 4, multi-arm, high-throughput metabolomics platforms., Results: The average laboratory coefficient of variation (CV) on the 4 platforms was between 9.3 and 11.5% (median, 6.5-8.4%), average inter-assay CV on the 4 platforms ranged from 9.9 to 12.6% (median, 7.0-8.3%) and average intra-assay CV on the 4 platforms ranged from 5.7 to 6.9% (median, 3.5-4.4%). In relation to patient sample testing, the precision of multiple biomarkers associated with IEM disorders showed CVs that ranged from 0.2 to 11.0% across 4 analytical batches., Conclusions: This evaluation describes single and multi-day precision across 4 identical metabolomics platforms, comprised each of 4 independent method arms, and reproducibility of the method for the measurement of key IEM metabolites in patient samples across multiple analytical batches, providing evidence that the method is robust and reproducible for the screening of patients with inborn errors of metabolism., (© American Association for Clinical Chemistry 2020. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

The purpose of this study is to evaluate functional outcomes and complications between the standard RSA and BIO-RSA. 65 consecutive procedures were performed in 60 patients (40 BIO-RSA and 25 RSA). There was no statistically significant difference in functional outcome, pain and complications. The BIO-RSA can produce comparable, if not better functional results than a standard RSA whilst reducing the rates of scapula notching, prosthesis instability, lost shoulder rotation and poor shoulder contour. It should therefore be considered in all patients presenting with cuff tear arthropathy, massive rotator cuff tear and fracture sequelae., (© 2019 Professor P K Surendran Memorial Education Foundation. Published by Elsevier B.V. All rights reserved.)

Preclinical research shows that compounds acting at α7 nicotinic receptors (nAChRs) can reduce nicotine self-administration, suggesting that a positive allosteric modulator (PAM) of α7 receptors, JNJ-39393406, may aid smoking cessation. Moreover, individuals with schizophrenia, who have very high rates of smoking, have reduced expression of α7 nAChRs and may particularly benefit from this compound. In two parallel studies using a within-subject cross-over design, 36 healthy smokers (Study 1) and 62 smokers with schizophrenia (Study 2), both groups high in quit interest, attempted to initiate quitting temporarily during each of two 3-week phases. Treatments were the α7 nicotinic receptor PAM JNJ-39393406 (100 mg b.i.d.) or placebo (double-blind, counter-balanced). In each phase, all smoked ad lib with no drug on week 1 or during dose run-up on week 2, and then tried to quit every day during week 3. Abstinence (confirmed by CO <5 p.p.m.) and smoking reduction (CO <8), as well as cigarettes/day (in Study 1), were assessed daily (Monday-Friday) each quit week and compared between conditions. Secondary outcomes included abstinence symptoms (withdrawal and craving) and cognitive test responding (N-back; continuous performance task). In both studies, compared with placebo, active JNJ-39393406 did not increase the number of abstinent days nor reduce total smoking exposure. We also found no significant improvements in craving, withdrawal, or cognitive function. With this dose and study duration, our findings do not support further testing of this α7 nAChR PAM compound for possible efficacy in smoking cessation, in smokers with or without schizophrenia.

Study Design: Retrospective review of a prospectively collected database., Objective: To assess the incidence of deep vein thrombosis (DVT) associated with single- versus multistage posterior-only complex spinal surgeries., Summary of Background Data: Dividing the physiologic burden of spinal deformity surgery into multiple stages has been suggested as a potential means of reducing perioperative complications. DVT is a worrisome complication owing to its potential to lead to pulmonary embolism. Whether or not staging affects DVT incidence in this population is unknown., Methods: Consecutive patients undergoing either single- or multistage posterior complex spinal surgeries over a 12-year period at a single institution were eligible. All patients received lower extremity venous duplex ultrasonographic (US) examinations 2 to 4 days postoperatively in the single-stage group and 2 to 4 days postoperatively after each stage in the multistage group. Multivariate logistic regression was used to assess the independent contribution of staging to developing a DVT., Results: A total of 107 consecutive patients were enrolled-26 underwent multistage surgery and 81 underwent single-stage surgery. The single-stage group was older (63 years vs. 45 years; p < .01) and had a higher Charlson comorbidity index (2.25 ± 1.27 vs. 1.23 ± 1.58; p < .01). More multistage patients had positive US tests than single-stage patients (5 of 26 vs. 6 of 81; 19% vs. 7%; p = .13). Adjusting for all the above-mentioned covariates, a multistage surgery was 8.17 (95% CI 0.35-250.6) times more likely to yield a DVT than a single-stage surgery., Conclusions: Patients who undergo multistage posterior complex spine surgery are at a high risk for developing a DVT compared to those who undergo single-stage procedures. The difference in DVT incidence may be understated as the multistage group had a lower pre- and intraoperative risk profile with a younger age, lower medical comorbidities, and less per-stage blood loss., (Copyright © 2017 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.)

Introduction: A major bottleneck in metabolomic studies is metabolite identification from accurate mass spectrometric data. Metabolite x17299 was identified in plasma as an unknown in a metabolomic study using a compound-centric approach where the associated ion features of the compound were used to determine the true molecular mass., Objectives: The aim of this work is to elucidate the chemical structure of x17299, a new compound by de novo interpretation of mass spectrometric data., Methods: An Orbitrap Elite mass spectrometer was used for acquisition of mass spectra up to MS 4 at high resolution. Synthetic standards of N,N,N -trimethyl-l-alanyl-l-proline betaine (l,l-TMAP), a diastereomer, and an enantiomer were chemically prepared., Results: The planar structure of x17299 was successfully proposed by de novo mechanistic interpretation of mass spectrometric data without any laborious purification and nuclear magnetic resonance spectroscopic analysis. The proposed structure was verified by deuterium exchanged mass spectrometric analysis and confirmed by comparison to a synthetic standard. Relative configuration of x17299 was determined by direct chromatographic comparison to a pair of synthetic diastereomers. Absolute configuration was assigned after derivatization of x17299 with a chiral auxiliary group followed by its chromatographic comparison to a pair of synthetic standards., Conclusion: The chemical structure of metabolite x17299 was determined to be l,l-TMAP.

Early detection of insulin resistance (IR) and/or impaired glucose tolerance (IGT) is crucial for delaying and preventing the progression toward type 2 diabetes. We recently developed and validated a straightforward metabolite-based test for the assessment of IR and IGT in a single LC-MS/MS method. Plasma samples were diluted with isotopically-labeled internal standards and extracted by simple protein precipitation. The extracts were analyzed by LC-MS/MS for the quantitation of 2-hydroxybutyric acid (0.500-40.0μg/mL), 3-hydroxybutyric acid (1.00-80.0μg/mL), 4-methyl-2-oxopentanoic acid (0.500-20.0μg/mL), 1-linoleoyl-2-hydroxy-sn-glycero-3-phosphocholine (2.50-100μg/mL), oleic acid (10.0-400μg/mL), pantothenic acid (0.0100-0.800μg/mL), and serine (2.50-100μg/mL). Liquid chromatography was carried out on a reversed phase column with a run time of 3.1min and the mass spectrometer operated in negative MRM mode. Method validation was performed on three identical LC-MS/MS systems with five runs each. Sufficient linearity (R 2 >0.99) was observed for all the analytes over the ranges. The imprecision (CVs) was found to be less than 5.5% for intra-run and less than 5.8% for inter-run for the seven analytes. The analytical recovery was determined to be between 96.3 and 103% for the seven analytes. This fast and robust method has subsequently been used for patient sample analysis for the assessment of IR and IGT., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Importance: Cerebral amyloid-β aggregation is an early pathological event in Alzheimer disease (AD), starting decades before dementia onset. Estimates of the prevalence of amyloid pathology in persons without dementia are needed to understand the development of AD and to design prevention studies., Objective: To use individual participant data meta-analysis to estimate the prevalence of amyloid pathology as measured with biomarkers in participants with normal cognition, subjective cognitive impairment (SCI), or mild cognitive impairment (MCI)., Data Sources: Relevant biomarker studies identified by searching studies published before April 2015 using the MEDLINE and Web of Science databases and through personal communication with investigators., Study Selection: Studies were included if they provided individual participant data for participants without dementia and used an a priori defined cutoff for amyloid positivity., Data Extraction and Synthesis: Individual records were provided for 2914 participants with normal cognition, 697 with SCI, and 3972 with MCI aged 18 to 100 years from 55 studies., Main Outcomes and Measures: Prevalence of amyloid pathology on positron emission tomography or in cerebrospinal fluid according to AD risk factors (age, apolipoprotein E [APOE] genotype, sex, and education) estimated by generalized estimating equations., Results: The prevalence of amyloid pathology increased from age 50 to 90 years from 10% (95% CI, 8%-13%) to 44% (95% CI, 37%-51%) among participants with normal cognition; from 12% (95% CI, 8%-18%) to 43% (95% CI, 32%-55%) among patients with SCI; and from 27% (95% CI, 23%-32%) to 71% (95% CI, 66%-76%) among patients with MCI. APOE-ε4 carriers had 2 to 3 times higher prevalence estimates than noncarriers. The age at which 15% of the participants with normal cognition were amyloid positive was approximately 40 years for APOE ε4ε4 carriers, 50 years for ε2ε4 carriers, 55 years for ε3ε4 carriers, 65 years for ε3ε3 carriers, and 95 years for ε2ε3 carriers. Amyloid positivity was more common in highly educated participants but not associated with sex or biomarker modality., Conclusions and Relevance: Among persons without dementia, the prevalence of cerebral amyloid pathology as determined by positron emission tomography or cerebrospinal fluid findings was associated with age, APOE genotype, and presence of cognitive impairment. These findings suggest a 20- to 30-year interval between first development of amyloid positivity and onset of dementia.

Introduction: There is a critical need to develop clinical laboratory assays that provide risk assessment for men at elevated risk for prostate cancer, and once diagnosed, could further identify those men with clinically significant disease., Methods: Recent advancements in analytical instrumentation have enabled mass spectrometry-based metabolomics methodologies. Further advancements in chromatographic techniques have facilitated high throughput, quantitative assays for a broad spectrum of biochemicals., Results: Screening metabolomics techniques have been applied to biospecimens from large cohorts of men comparing those individuals with prostate cancer to those with no evidence of malignancy. Work beginning in tissues has identified biochemical profiles that correlate with disease and disease severity, including tumor grade and stage. Some of these metabolic abnormalities, such as dramatic elevations in sarcosine, have been found to translate into biological fluids, especially blood and urine, which can be sampled in a minimally invasive manner., Discussion: The differential abundances of these tumor-associated metabolites have been found to improve the performance of clinical prognostic/diagnostic tools., Conclusion: The outlook is bright for metabolomic technology to address clinical diagnostic needs for prostate cancer patient management. Early validation of specific clinical tests provides a preview of further successes in this area. Metabolomics has shown its utility to complement and augment traditional clinical approaches as well as emerging genomic, transcriptomic and proteomic methodologies, and is expected to play a key role in the precision medicine-based management of the prostate cancer patient.

Purpose: To evaluate fetal or neonatal outcomes (with a focus on major congenital anomalies) with use of topiramate monotherapy and to examine whether differences occurred in the reporting and patterns of these outcomes for pregnant women with and without epilepsy., Methods: Spontaneous, postmarketing reports involving women who used topiramate monotherapy during pregnancy from 18 July 1995 (International Birth Date of topiramate) through 30 April 2011 were retrieved from the sponsor's (Janssen Research & Development, LLC) Global Medical Safety database. All formulations for topiramate, used as monotherapy, were selected for the analysis. Monotherapy was defined as any situation where no other AED was listed in the pregnancy case report, either as a suspect or concomitant medication, regardless of indication. Results were summarized descriptively., Results: A total of 1163 cases of women who used topiramate monotherapy during pregnancy (for any indication) were retrieved from the Global Medical Safety database. Since some women used topiramate for more than one indication, there were a total of 1199 reported indications for topiramate monotherapy, which were primarily for treatment of epilepsy (n=599), accounting for half of the indications, and migraine prophylaxis (n=240, 20.0%). Out of 1163 cases, pregnancy outcome was reported in 50.6% (n=589). Live birth was the most frequently reported outcome, regardless of indication (epilepsy, 78.8% [312/396]; prophylaxis of migraine, 59. 3% [48/81]; other indication, 64.4% [85/132]). Cleft lip or palate anomalies (epilepsy, n=15; migraine, n=2; other indication, n=4; and indication not reported, n=2), limb, hand, or other skeletal anomalies (epilepsy, n=13; migraine, n=2; other indication, n=0; and indication not reported, n=1), and respiratory or cardiovascular anomalies (epilepsy, n=12; migraine, n=1; other indication, n=1; and indication not reported, n=2) were the most often reported major fetal or neonatal anomalies. More reported major fetal or neonatal anomalies occurred in patients being treated for epilepsy (53/79 anomaly-indication pairs) compared with patients being treated for migraine prophylaxis (10/79 anomaly-indication pairs)., Conclusion: Although incidence rates cannot be calculated based on spontaneous adverse event reporting, this summary of reported pregnancy and neonatal outcomes with use of topiramate monotherapy suggests that the risk for major fetal or neonatal anomalies may differ based on the indication for topiramate., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: In 2009, 58.6 million UK residents traveled abroad. Of these, 49.5 million (84.5%) visits were to Europe and North America and 9.1 million (15.5%) were to other parts of the world. Rabies is widely distributed and continues to be a major public health issue in many developing countries. The UK is free of rabies in carnivore host species, although cases of rabies in bats have been reported. This study examined the rabies postexposure prophylaxis (PEP) service from 2000 to July 2009 at the Liverpool School of Tropical Medicine., Methods: Medical records of patients who attended the clinic for rabies PEP were reviewed., Results: During the study period, 139 patients were treated for possible rabies exposure. The mean age was 35 years. Thailand and Turkey each accounted for 31 (22.3%) cases. Sixty-nine (49.6%) of those seen were due to dog bites. Most injuries involved a lower limb (n = 67, 48.2%) or hands (n = 26, 18.7%). Eighty-six (61.9%) cases had initiated rabies PEP overseas, but only 3 of the 78 (3.8%) meeting UK criteria for rabies immunoglobulin (RIG) received it while overseas. Only an additional 11 patients received RIG on return to the UK; most were seen more than 7 days after initiation of PEP. The median time from exposure to receiving rabies PEP was 1 day (range: 0-1,720). Only 14 (10.1%) had received preexposure rabies vaccination., Conclusions: The majority of travelers seeking PEP at this clinic initiated treatment overseas. Most had not received RIG abroad, when it would have been appropriate. Initiation of appropriate treatment is often delayed and is a concern to those without preexposure rabies immunization. In view of the scarcity of RIG, travelers need to be aware of the risks, consider preexposure immunization, and present early for PEP., (© 2011 International Society of Travel Medicine.)

Objective: The objective of this multicenter, international study was to evaluate safety and tolerability of paliperidone extended-release (ER) tablets in elderly (age > or =65 years) patients with schizophrenia. The authors conducted a 6-week, double-blind, randomized, placebo-controlled, optional 24-week open-label extension study. Interventions consisted of flexible, once-daily doses of paliperidone ER (3-12 mg/day; 6-mg starting dose, adjusted in 3-mg dose increments) or placebo (2:1) during double-blind treatment and paliperidone ER only during open-label treatment. Measurements included adverse events, laboratory tests, physical examinations, 12-lead electrocardiograms, movement disorder rating scales, Positive and Negative Syndrome Scale, and Clinical Global Impression scale. The study was not powered to show statistical differences., Results: Patients (N = 114) were predominantly female (73%); mean age was 70 years (double-blind phase). Concomitant disease presence was consistent with that of an older population. During the double-blind phase, discontinuation rates resulting from adverse events were similar between groups (paliperidone ER: 7%, placebo: 8%) as were incidences of treatment-emergent adverse events (paliperidone ER: 67%, placebo: 71%). Serious adverse events occurred in 3% of the paliperidone ER- and 8% of the placebo-treated patients. Elevated prolactin levels occurred in approximately one half of patients. No prolactin- or glucose treatment-related adverse events or noteworthy mean changes in body weight (0 kg [standard deviation: 2.1] and 0 kg [standard deviation: 2.3] for paliperidone ER and placebo, respectively) were observed. Safety and tolerability results in the extension were consistent with the shorter-term results. Efficacy measures did not show consistent statistical improvement between treatment groups., Conclusion: Paliperidone ER (3-12 mg/day) treatment over a 30-week period was generally well-tolerated and may improve symptom severity in elderly patients with schizophrenia.