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Anxiety and trauma related disorders are highly prevalent, causing suffering and high costs for society. Current treatment strategies, although effective, only show moderate effect-sizes when compared to adequate control groups demonstrating a need to develop new forms of treatment or optimize existing ones. In order to achieve this, an increased understanding of what mechanisms are involved is needed. An emerging literature indicates that mindfulness training (MFT) can be used to treat fear and anxiety related disorders, but the treatment mechanisms are unclear. One hypothesis, largely based on findings from neuroimaging studies, states that MFT may improve extinction retention, but this has not been demonstrated empirically. To investigate this question healthy subjects either completed a 4-week MFT- intervention delivered through a smart-phone app (n = 14) or were assigned to a waitlist (n = 15). Subsequently, subjects participated in a two-day experimental protocol using pavlovian aversive conditioning, evaluating acquisition and extinction of threat-related responses on day 1, and extinction retention on day 2. Results showed that the MFT group displayed reduced spontaneous recovery of threat related arousal responses, as compared to the waitlist control group, on day 2. MFT did not however, have an effect on either the acquisition or extinction of conditioned responses day 1. This clarifies the positive effect of MFT on emotional functioning and could have implications for the treatment of anxiety and trauma related disorders.

Virtual reality lets the user be immersed in a 3-dimensional environment, which can enhance certain emotional responses to stimuli relative to experiencing them on a flat computer screen. We here tested whether displaying two different types of threats in immersive virtual reality enhanced threat related autonomic responses measured by skin conductance responses (SCRs). We studied innate and learned threat responses because these types of threats have been shown to depend on different neural circuits in animals. Therefore, it is possible that immersive virtual reality may modulate one of these threats but not the other. Innate threat responses were provoked by the sudden appearance of characters at proximal egocentric distance, which were compared to the sudden appearance of distant characters (proximal threat). Learned threat responses were studied by conditioning two of the characters to an electric shock (conditioned threat) and contrasting SCRs to these characters with SCRs to two other characters that were never paired with shock. We found that displaying stimuli in immersive virtual reality enhanced proximal threat responses but not conditioned threat responses. Findings show that immersive virtual reality can enhance an innate type of threat responses without affecting a learned threat response, suggesting that separate neural pathways serve these threat responses.

Background: There is a need to educate a range of professionals in caring for individuals with long-term mental disability who reside within our communities. Empathy alone is insufficient. The Kognus 4-Step Education Program was developed to achieve this goal., Method: The program consisted of independent courses, including an 18-session basic course on psychiatric disability (on-site or online), advanced courses, and highly specialized training programs (Nidotherapy/Peer Consultation). Experts lectured together with clients with psychiatric disabilities. We first report Swedish reforms in which institutionalized patients were relocated to semi-independent individual households. We then describe the design and implementation of the education program. Approximately 50% of participants who were younger than 36 years old lacked any healthcare education. The participants' backgrounds, perceptions, participation in the education program, and costs are presented., Results: Between 2009 and 2014, 8959 participants attended the Kognus psychiatry courses online or on-site in Stockholm (basic on-site course, n = 2111; online course, n = 4480; advanced courses, n = 2322; highly specialized programs, n = 46). A total of 73% of the participants satisfactorily attended the basic sessions on-site compared with 11% of the online participants. The developers conducted the education program for the first 3 years. Thereafter, another course provider continued the program with other types of participants. The program was perceived to be equally interesting and meaningful to participants with low and high levels of education, demonstrating the generalizability of the program. The quality of the basic and advanced courses was rated as 4.4 and 4.3, respectively, on a 5-point Likert scale., Conclusions: Personnel without appropriate education who work with people with psychiatric/intellectual disabilities can be educated in large numbers. The Kognus program represents a novel and successful way of training people who have no formal education about some essentials of good mental healthcare. Moreover, the model can be easily implemented elsewhere.

Motivation: Validation of variable selection and predictive performance is crucial in construction of robust multivariate models that generalize well, minimize overfitting and facilitate interpretation of results. Inappropriate variable selection leads instead to selection bias, thereby increasing the risk of model overfitting and false positive discoveries. Although several algorithms exist to identify a minimal set of most informative variables (i.e. the minimal-optimal problem), few can select all variables related to the research question (i.e. the all-relevant problem). Robust algorithms combining identification of both minimal-optimal and all-relevant variables with proper cross-validation are urgently needed., Results: We developed the MUVR algorithm to improve predictive performance and minimize overfitting and false positives in multivariate analysis. In the MUVR algorithm, minimal variable selection is achieved by performing recursive variable elimination in a repeated double cross-validation (rdCV) procedure. The algorithm supports partial least squares and random forest modelling, and simultaneously identifies minimal-optimal and all-relevant variable sets for regression, classification and multilevel analyses. Using three authentic omics datasets, MUVR yielded parsimonious models with minimal overfitting and improved model performance compared with state-of-the-art rdCV. Moreover, MUVR showed advantages over other variable selection algorithms, i.e. Boruta and VSURF, including simultaneous variable selection and validation scheme and wider applicability., Availability and Implementation: Algorithms, data, scripts and tutorial are open source and available as an R package ('MUVR') at https://gitlab.com/CarlBrunius/MUVR.git., Supplementary Information: Supplementary data are available at Bioinformatics online., (© The Author(s) 2018. Published by Oxford University Press.)

Preparedness theory is one of the most influential ideas in explaining the origin of specific phobias. The theory proposes that fear conditioning is selective to animals that have posed a threat to survival throughout human evolution, and that acquired fear memories to such threats are resistant to extinction. We reviewed fear conditioning studies testing whether autonomic responses conditioned to pictures of snakes and spiders show greater resistance to extinction than neutral cues. We identified 32 fear conditioning experiments published in 23 studies including 1887 participants. Increased resistance to extinction of conditioned responses to snake and spider pictures was found in 10 (31%) of the experiments, whereas 22 (69%) experiments did not support the hypothesis. Thus, the body of evidence suggests that preparedness theory does not explain the origin of specific phobias., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A non-target analysis method for unexpected contaminants in food is described. Many current methods referred to as "non-target" are capable of detecting hundreds or even thousands of contaminants. However, they will typically still miss all other possible contaminants. Instead, a metabolomics approach might be used to obtain "true non-target" analysis. In the present work, such a method was optimized for improved detection capability at low concentrations. The method was evaluated using 19 chemically diverse model compounds spiked into milk samples to mimic unknown contamination. Other milk samples were used as reference samples. All samples were analyzed with UHPLC-TOF-MS (ultra-high-performance liquid chromatography time-of-flight mass spectrometry), using reversed-phase chromatography and electrospray ionization in positive mode. Data evaluation was performed by the software TracMass 2. No target lists of specific compounds were used to search for the contaminants. Instead, the software was used to sort out all features only occurring in the spiked sample data, i.e., the workflow resembled a metabolomics approach. Procedures for chemical identification of peaks were outside the scope of the study. Method, study design, and settings in the software were optimized to minimize manual evaluation and faulty or irrelevant hits and to maximize hit rate of the spiked compounds. A practical detection limit was established at 25 μg/kg. At this concentration, most compounds (17 out of 19) were detected as intact precursor ions, as fragments or as adducts. Only 2 irrelevant hits, probably natural compounds, were obtained. Limitations and possible practical use of the approach are discussed.

There is a need for large-scale remote data collection in a controlled environment, and the in-home availability of virtual reality (VR) and the commercial availability of eye tracking for VR present unique and exciting opportunities for researchers. We propose and provide a proof-of-concept assessment of a robust system for large-scale in-home testing using consumer products that combines psychophysiological measures and VR, here referred to as a Virtual Lab. For the first time, this method is validated by correlating autonomic responses, skin conductance response (SCR), and pupillary dilation, in response to a spider, a beetle, and a ball using commercially available VR. Participants demonstrated greater SCR and pupillary responses to the spider, and the effect was dependent on the proximity of the stimuli to the participant, with a stronger response when the spider was close to the virtual self. We replicated these effects across two experiments and in separate physical room contexts to mimic variability in home environment. Together, these findings demonstrate the utility of pupil dilation as a marker of autonomic arousal and the feasibility to assess this in commercially available VR hardware and support a robust Virtual Lab tool for massive remote testing.

Surfactants may cause dysfunction of intestinal tight junctions (TJs), which is a common feature of intestinal autoimmune diseases. Effects of dietary surfactants on TJ integrity, measured as trans-epithelial resistance (TEER), were studied in Caco-2 cell monolayers. Cytotoxicity was assessed as apical LDH leakage. Monolayers were apically exposed for 60 min to the dietary surfactants solanine and chaconine (SC, potato glycoalkaloids, 0-0.25 mM), perfluorooctane sulfonic acid (PFOS, industrial contaminant, 0-0.8 mM), and sucrose monolaurate (SML, food emulsifier E 473, 0-2.0 mM) separately and as a mixture. Dose-response modelling of TEER EC 50 showed that SC were 2.7- and 12-fold more potent than PFOS and SML, respectively. The mixture was composed of 1 molar unit SC, 2.7 units PFOS and 12 units SML ("SC TEER equivalent" proportions 1:1:1). Mixture exposure (0-0.05 mM SC equivalents) dose-response modelling suggested additive action on TJ integrity. Increasing SC and SML concentrations caused increased LDH leakage, but PFOS decreased LDH leakage at intermediate exposure concentrations. In the mixture PFOS appeared to protect from extensive SC- and SML-induced LDH leakage. Complex mixtures of surfactants in food may act additively on intestinal TJ integrity, which should be considered in risk assessment of emulsifier authorisation for use in food production., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Responding to threats in the environment is crucial for survival. Certain types of threat produce defensive responses without necessitating previous experience and are considered innate, whereas other threats are learned by experiencing aversive consequences. Two important innate threats are whether an encountered stimulus is a member of the same species (social threat) and whether a stimulus suddenly appears proximal to the body (proximal threat). These threats are manifested early in human development and robustly elicit defensive responses. Learned threat, on the other hand, enables adaptation to threats in the environment throughout the life span. A well-studied form of learned threat is fear conditioning, during which a neutral stimulus acquires the ability to eliciting defensive responses through pairings with an aversive stimulus. If innate threats can facilitate fear conditioning, and whether different types of innate threats can enhance each other, is largely unknown. We developed an immersive virtual reality paradigm to test how innate social and proximal threats are related to each other and how they influence conditioned fear. Skin conductance responses were used to index the autonomic component of the defensive response. We found that social threat modulates proximal threat, but that neither proximal nor social threat modulates conditioned fear. Our results suggest that distinct processes regulate autonomic activity in response to proximal and social threat on the one hand, and conditioned fear on the other., (Copyright © 2017 Elsevier Inc. All rights reserved.)

A new method was developed for analysis of free β-Methylamino-alanine (BMAA) in biological matrices. The method is based on direct analysis of the underivatized molecule, using an amide column for separation by Hydrophilic Interaction Liquid Chromatography (HILIC) and detection by tandem mass spectrometry (MS/MS) using a deuterium labeled internal standard. The use of Ultra-High Performance Liquid Chromatography (UHPLC) combined with MS/MS detection allowed for high chromatographic resolution and a low limit of detection (0.025 μg/g wet weight (ww) in mussels). The method was validated by analyzing spiked blank mussels from the Baltic Sea (0.15-4.4 μg/g (ww), trueness 99%-105%, RSD 2%-8%). An inter-laboratory comparative analysis of extracts of mussel was performed. The mussels were extracted according to an established protocol for analysis of free BMAA, and the extracts were then analyzed in parallel by the new method and a validated procedure based on detection of BMAA derivatized with dansyl chloride. Both methods detected BMAA in similar concentrations. Thus, derivatization with dansyl chloride did not influence the results compared to direct detection. The new method presents an alternative to the commonly applied derivatization step, and is proved through validation and method comparison to reliably identify and quantify free BMAA at low concentration levels., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In this case report we illustrate how incorrectly prepared and cooked seeds from white lupin - a common snack among people from parts of the Mediterranean and Middle East - caused an anticholinergic syndrome in a previously healthy man. The symptoms subsided without treatment and the patient was discharged from the hospital in good health. Anticholinergic syndrome results from inhibition of the parasympatic nervous system. The symptoms commonly include dry mouth, confusion, hallucinations, fever, tachycardia, and urine retention. The syndrome may most frequently be provoked by overdose of drugs such as prometazin, hyoscyamin, and biperidin or by ingestion of plants such as belladonna, datura and henbane. The aim of this report is to increase clinicians' awareness of white lupin's anticholinergic effects.

The results of this study imply that β-methylamino-alanine (BMAA) obtained from extracts of blue mussels from the Swedish west coast is neither free nor protein bound. The results were obtained by separation (precipitation and ultrafiltration) of low and high molecular weight compounds from neutral extracts of blue mussels, and treatment of these extracts with low and high concentrations of acids, varying time and temperature. The main portion of BMAA was obtained from the low molecular weight fraction, released or formed at 95 °C in dilute acids. The measured amount of BMAA did not increase by strong acid treatment. Lysine was used as reference and was only released at significant amounts when treating the high molecular weight fraction with concentrated acid. The results also indicated that breakage of peptide bonds was not involved in the formation/release of BMAA in these extracts unless any BMAA peptide bond would be significantly more susceptible to dilute acid than e.g. the monitored lysine peptide bond. BMAA was measured using isotope dilution and detection of the underivatized compound by HILIC-UHPLC-MS/MS (Hydrophilic Interaction Liquid Chromatography, Ultra-High Performance Liquid Chromatography, tandem Mass Spectrometry). The findings might add to the understanding of conflicting data in the literature regarding the occurrence of BMAA, and have implications for studies on possible biomagnification of BMAA in the food chain and bioavailability from food., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A method that uses mass spectrometry (MS) for identification and quantification of protein toxins, staphylococcal enterotoxins A and B (SEA and SEB), in milk and shrimp is described. The analysis was performed using a tryptic peptide, from each of the toxins, as the target analyte together with the corresponding (13)C-labeled synthetic internal standard peptide. The performance of the method was evaluated by analyzing spiked samples in the quantification range 2.5-30 ng/g (R² = 0.92-0.99). The limit of quantification (LOQ) in milk and the limit of detection (LOD) in shrimp was 2.5 ng/g, for both SEA and SEB toxins. The in-house reproducibility (RSD) was 8%-30% and 5%-41% at different concentrations for milk and shrimp, respectively. The method was compared to the ELISA method, used at the EU-RL (France), for milk samples spiked with SEA at low levels, in the quantification range of 2.5 to 5 ng/g. The comparison showed good coherence for the two methods: 2.9 (MS)/1.8 (ELISA) and 3.6 (MS)/3.8 (ELISA) ng/g. The major advantage of the developed method is that it allows direct confirmation of the molecular identity and quantitative analysis of SEA and SEB at low nanogram levels using a label and antibody free approach. Therefore, this method is an important step in the development of alternatives to the immune-assay tests currently used for staphylococcal enterotoxin analysis.

The neurotoxin β-N-methylamino-L-alanine (BMAA) produced naturally by cyanobacteria, diatoms and dinoflagellates can be transferred and accumulated up the food chain, and may be a risk factor for neurodegenerative diseases. This study provides the first systematic screening of BMAA exposure of a large population through the consumption of seafood sold in metropolitan markets. BMAA was distinguished from known isomers by liquid chromatography tandem mass spectrometry after acidic hydrolysis and derivatization. Using deuterium-labeled internal standard, BMAA was quantified as 0.01-0.90 μg/g wet weight of tissues in blue mussel, oyster, shrimp, plaice, char and herring, but was undetectable (<0.01 μg/g) in other samples (salmon, cod, perch and crayfish). Provided that the content of BMAA detected is relevant for intake calculations, the data presented may be used for a first estimation of BMAA exposure through seafood from Swedish markets, and to refine the design of future toxicological experiments and assessments.

In this study serum levels of bisphenol A (BPA) were investigated in primiparous women from Uppsala County, Sweden, sampled 3weeks after delivery 1996-2011, in both yearly pools of serum (n=39, temporal trend study) and in 208 individual samples also present in the pools. Possible contamination risks of BPA from blood sampling equipment and sample tubes, as well as from handling of the samples were evaluated. The unconjugated form of BPA was analyzed using a UPLC-MS/MS method with a limit of quantification (LOQ) of 0.2ng/ml. The results show that the levels of unconjugated BPA generally were <0.2ng/ml. The sampling equipment used when taking blood samples from the women and the tubes used for storage and processing of samples did not show any detectable BPA leakage. In the first analysis of the serum samples, unconjugated BPA levels ≥0.2ng/ml were found in 12% of the individual samples and in 21% of the trend samples. However, in reanalyses of individual serum samples from the same aliquot or from new aliquots, samples with BPA levels ≥0.2ng/ml in the first analysis did not have quantifiable BPA levels. Moreover, 11% of BPA spiked calibration samples (over 200) had higher levels than could be explained by the random error of the method. Thus BPA contamination of the biobanked samples probably occurred randomly during sample handling, pooling and processing. Equipment used for sampling of children and repeated blood sampling were leaking BPA. The results show the difficulties in analyzing compounds where samples are easily contaminated from exogenous sources. It also points out that it is questionable to use biobanked samples unless absence of BPA contamination from the sampling and storage materials, and during handling of the samples, can be proven., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A generic method to screen for new or unexpected contaminants at ppm levels in food has been developed. The method comprises an acidic acetonitrile extraction, detection with ultra-high-pressure liquid chromatography coupled to electrospray ionisation time-of-flight mass spectrometry and statistical evaluation using a metabolomics approach comparing suspected contaminated food with uncontaminated foods. The method was tested for 26 model contaminants from 100 μg/g down to 0.4 μg/g in three brands of fresh orange juice. Blinded statistical evaluation revealed signals from all added contaminants detectable by liquid chromatography-electrospray ionisation using positive ionisation mode, while only two false-positive signals were reported. The method is primarily intended to be used for investigation of food samples suspected to be contaminated with unknown substances. Additionally it could be used to continuously monitor for appearance of new food contaminants as a complement to the specific targeted analysis that is today's foundation of food safety analysis.

Orellanine is a nephrotoxin found in various Cortinaceae mushroom species. Unintentional consumption after these species were confused with edible mushrooms such as Cantharellus tubaeformis has caused several casualties. In this work, a quantitative HPLC-ESI-MS/MS method for total orellanine in Cortinarius rubellus, spiked blood plasma, and a mushroom stew prepared from C. tubaeformis with the addition of a single specimen of C. rubellus is presented. The existence of mono- and diglucosylated orellanine in C. rubellus was also proven, although quantitative analysis could not be obtained for the glucosides due to rapid hydrolyzation to orellanine in the extract. Extraction with 3 M HCl or water mainly yielded orellanine, while MeOH or acidified MeOH mainly extracted mono- and diglucosylated orellanine. The highest recovery of total orellanine was obtained with 3 M HCl, which was subsequently used for quantitative analysis. A C₁₈ HPLC column and low pH in the eluents retained all these toxins. Orellanine could be detected at a 4.9 ng/mL level in all extracts, which is well below the threshold for acute toxic effects. Additionally, the fragmentation pattern of orellanine upon electrospray MS/MS was probed. The method described is useful for two important applications. First, it allows quantitative analysis of processed food products that may be contaminated by orellanine from Cortinaceae mushrooms. Second, orellanine is currently being evaluated as a potential cure of metastatic renal cancer, and this work provides a method for monitoring orellanine at low concentrations within the therapeutic interval in blood serum.

Since the advent of theoretical materials science some 60 years ago, there has been a drive to predict and design new materials in silicio. Mathematical optimization procedures to determine phase stability can be generally applicable to complex ternary or higher-order materials systems where the phase diagrams of the binary constituents are sufficiently known. Here, we employ a simplex-optimization procedure to predict new compounds in the ternary Nb-Ge-C system. Our theoretical results show that the hypothetical Nb2GeC is stable, and excludes all reasonably conceivable competing hypothetical phases. We verify the existence of the Nb2GeC phase by thin film synthesis using magnetron sputtering. This hexagonal nanolaminated phase has a and c lattice parameters of ∼3.24  Å and 12.82 Å.

Partial least squares (PLS) regression is a flexible data analytical approach, which can be made even more versatile and useful by various modifications. In this article we describe the extension into orthogonal PLS modeling, in terms of two new methods, called OPLS and O2PLS, with similar prediction capacity but improved model interpretation., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A generic extraction procedure combined with triple quadrupole mass spectrometric detection was evaluated for multi-residue analysis in 19 different foods. Measurable peaks could be obtained at relevant concentrations for 108 out of a total of 127 targeted compounds representing a wide range of physicochemical properties and compound classes related to emergency situations. Recoveries were determined for all 19 foods spiked with the 108 compounds. Seventy-five percent of the compounds had extraction recoveries of 70% or higher, with no compound below 46%. Suppression or enhancement effects on the MS response of the compounds dissolved in the extracts were low, as more than 80% of them had matrix effects between -35% and +20% and no compound was below -44% compared to matrix-free standard. In a validation, all compounds could be quantified at 200 μg/kg and 400 μg/kg food sample and 81% of the compounds at 40 μg/kg. It is concluded that the method is useful for the detection of various types of organic chemical toxicants at levels generally well below concentration thresholds for severe acute intoxication., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Purpose: To evaluate the usefulness of a miniaturized rotating disk equipment for the determination of factors influencing the in vitro dissolution rate, G, of a model basic drug substance (terfenadine) in different aqueous media, using experimental design and multivariate data analysis. The apparent solubility, S, was included in the chemometric study., Methods: The dissolution rate was determined with a miniaturized rotating disk apparatus and the solubility by shake-flask methodology. Media were based on acetate, phosphate or maleate buffers-the latter used in fasted state simulated intestinal fluid (FaSSIF-V2). The chemometric analyses included fractional factorial design, principal component analysis (PCA) and orthogonal partial least squares (OPLS). Quantifications were made with a RP-HPLC-DAD system., Results: The most influential factor for both G and S of terfenadine in the different media was pH. Apart from the ionic strength and sodium chloride concentration in the acetate medium, the effects of the other variables were insignificant, implying no wetting effect of the surfactants., Conclusions: The miniaturized rotating disk equipment was suitable to use, in conjunction with the chemometric analyses, in the evaluation of the factors affecting the in vitro dissolution rate. The apparent solubility was found to be influenced by the same factors as G.

Cardiac glycosides have been reported to exhibit cytotoxic activity against several different cancer types, but studies against colorectal cancer are lacking. In a screening procedure aimed at identifying natural products with activity against colon cancer, several cardiac glycosides were shown to be of interest, and five of these were further evaluated in different colorectal cancer cell lines and primary cells from patients. Convallatoxin (1), oleandrin (4), and proscillaridin A (5) were identified as the most potent compounds (submicromolar IC50 values), and digitoxin (2) and digoxin (3), which are used in cardiac disease, exhibited somewhat lower activity (IC50 values 0.27-4.1 microM). Selected cardiac glycosides were tested in combination with four clinically relevant cytotoxic drugs (5-fluorouracil, oxaliplatin, cisplatin, irinotecan). The combination of 2 and oxaliplatin exhibited synergism including the otherwise highly drug-resistant HT29 cell line. A ChemGPS-NP application comparing modes of action of anticancer drugs identified cardiac glycosides as a separate cluster. These findings demonstrate that such substances may exhibit significant activity against colorectal cancer cell lines, by mechanisms disparate from currently used anticancer drugs, but at concentrations generally considered not achievable in patient plasma.

Natural products (NPs) are a rich source of novel compound classes and new drugs. In the present study we have used the chemical space navigation tool ChemGPS-NP to evaluate the chemical space occupancy by NPs and bioactive medicinal chemistry compounds from the database WOMBAT. The two sets differ notably in coverage of chemical space, and tangible leadlike NPs were found to cover regions of chemical space that lack representation in WOMBAT. Property based similarity calculations were performed to identify NP neighbors of approved drugs. Several of the NPs revealed by this method were confirmed to exhibit the same activity as their drug neighbors. The identification of leads from a NP starting point may prove a useful strategy for drug discovery in the search for novel leads with unique properties.

Internet has become a central source for information, tools, and services facilitating the work for medicinal chemists and drug discoverers worldwide. In this paper we introduce a web-based public tool, ChemGPS-NP(Web) (http://chemgps.bmc.uu.se), for comprehensive chemical space navigation and exploration in terms of global mapping onto a consistent, eight dimensional map over structure derived physico-chemical characteristics. ChemGPS-NP(Web) can assist in compound selection and prioritization; property description and interpretation; cluster analysis and neighbourhood mapping; as well as comparison and characterization of large compound datasets. By using ChemGPS-NP(Web), researchers can analyze and compare chemical libraries in a consistent manner. In this study it is demonstrated how ChemGPS-NP(Web) can assist in interpreting results from two large datasets tested for activity in biological assays for pyruvate kinase and Bcl-2 family related protein interactions, respectively. Furthermore, a more than 30-year-old suggestion of "chemical similarity" between the natural pigments betalains and muscaflavins is tested.

Objective: Acrylamide, a probable human carcinogen, is formed during high-heat cooking of many common foods. The validity of food frequency questionnaire (FFQ) measures of acrylamide intake has not been established. We assessed the validity of acrylamide intake calculated from an FFQ using a biomarker of acrylamide exposure., Methods: We calculated acrylamide intake from an FFQ in the Nurses' Health Study II. We measured hemoglobin adducts of acrylamide and its metabolite, glycidamide, in a random sample of 342 women. Correlation and regression analyses were used to assess the relationship between acrylamide intakes and adducts., Results: The correlation between acrylamide intake and the sum of acrylamide and glycidamide adducts was 0.31 (95% CI: 0.20-0.41), adjusted for laboratory batch, energy intake, and age. Further adjustment for BMI, alcohol intake, and correction for random within-person measurement error in adducts gave a correlation of 0.34 (CI: 0.23-0.45). The intraclass correlation coefficient for the sum of adducts was 0.77 in blood samples collected 1-3 years apart in a subset of 45 women. Intake of several foods significantly predicted adducts in multiple regression., Conclusions: Acrylamide intake and hemoglobin adducts of acrylamide and glycidamide were moderately correlated. Within-person consistency in adducts was high over time.

To investigate possible congruencies between DNA sequence data and secondary chemistry, we compared nuclear ribosomal DNA (nrDNA) sequence data, sesquiterpene lactone (STL) contents, and cytometric data from 35 accessions of 16 Arnica (Asteraceae) species and two outgroup taxa (Layia hieracioides and Madia sativa), using phylogenetic inference and principal component analysis (PCA). Several groups supporting multiple accessions of the same species (of A. montana, A. longifolia, A. gracilis, and A. chamissonis) are congruent between the phylogenetic trees based on nrDNA and STL data. Sesquiterpene lactone profiles were found to be highly consistent within multiple samples of A. montana and A. longifolia respectively. Moreover, sesquiterpene lactone data support subspecies classifications of A. chamissonis and A. parryi, with additional support from DNA sequence data and cytometric data. Morphology, STL data (PCA), cytometric data and DNA sequence data suggest a hybrid origin of one accession (A. gracilis × longifolia). In A. gracilis, A. latifolia, and Layia hieracioides, previously not investigated for STLs, we found large amounts of xanthalongin derivatives. This is the first time STLs have been reported from subtribe Madiinae. © The Willi Hennig Society 2009., (© The Willi Hennig Society 2009.)

A highly specific method for the analysis of beta-N-methylamino-L-alanine (BMAA) by LC-MS/MS (liquid chromatography tandem mass spectrometry) has been developed and applied for cycad seeds and cyanobacteria. BMAA was analysed as a free fraction or as total BMAA after acidic hydrolysis to release any protein-bound BMAA. Deuterium labelled BMAA was synthesised and used as internal standard. The method comprises HILIC (hydrophilic interaction chromatography) and positive electrospray ionisation of the native compound, i.e. no derivatisation was used. For safe identification five specific product ions (m/z 102, 88, 76, 73 and 44), all derived from a precursor ion of m/z 119 and originating from different parts of the molecule, were detected (typical relative abundance 100%, 16%, 14%, 12% and 22% respectively). Cyanobacteria or muscle tissue was spiked with BMAA (10 to 1000 microg g(-1)) to validate the method (accuracy 95% to 109%, relative standard deviation 1% to 6%). The detection limit for free and total BMAA in tissue was <1 microg g(-1) and <4 microg g(-1) respectively. BMAA was successfully identified and quantified in cycad seeds, whereas previously reported findings of BMAA in samples of cyanobacteria could not be confirmed. Instead, the presence of alpha-,gamma-diamino butyric acid (DAB), an isomer of BMAA, was confirmed in one sample. The possible implications of this finding are discussed.

A wide range of solid phases for SPE (solid-phase extraction) (n=14) and HPLC (n=9) were compared regarding the chromatographic retention of acrylamide. For SPE, a hydroxylated polystyrene-divinylbenzene copolymer phase (ENV+) gave the strongest retention. Twenty millilitre of water per gram solid phase could be passed with less than 5% loss of acrylamide from the column, thus enabling significant enrichment of food extracts. Other polymer phases gave varying degrees of retention, while silica bonded phases gave low retention. For HPLC, columns were evaluated both in reversed-phase and aqueous normal-phase (hydrophilic interaction chromatography) modes. The best retention was obtained with a phase comprising porous graphitic carbon (Hypercarb), giving a k-value of 4 with water as the mobile phase. Based on these investigations, a method for analysis of acrylamide in food using liquid chromatography-tandem mass spectrometry was designed to meet the demands of a collaborative validation trial. A comparative investigation of solid phases has not been published earlier. Thus, the paper should provide a base for new method developments regarding clean-up, enrichment and chromatography of acrylamide. In addition, the detailed standard operating procedure (SOP) method, as used in a collaborative validation trial, is provided as an electronic supplement (www.elsevier.com).

An industrial baking procedure for yeast-leavened whole-grain rye crisp bread was adapted to local laboratory conditions to study the effect of time and temperature of baking and the addition of fructose, asparagine, and oat-bran concentrate on the acrylamide content and color of the bread. Baking time and temperature affected acrylamide content that increased from 10 to 30 mug/kg of bread at the combination of a long time and high temperature, with a significant interaction between the two factors (p < 0.008). Added asparagine had a significant effect (p < 0.001) on the formation of acrylamide, but fructose did not. There was a correlation between acrylamide content and color of the milled bread in the time-temperature experiment, but this correlation was not observed in the experiment with added precursors. Added oat-bran concentrate with high content of mixed-linkage beta-glucan did not influence the acrylamide content in the breads.

A repeatable procedure for studying the effects of internal and external factors on acrylamide content in yeast-leavened wheat bread has been developed. The dough contained wheat endosperm flour with a low content of precursors for acrylamide formation (asparagine and reducing sugars), dry yeast, salt, and water. The effects of asparagine and fructose, added to the dough, were studied in an experiment with a full factorial design. More than 99% of the acrylamide was found in the crust. Added asparagine dramatically increased the content of acrylamide in crusts dry matter (from about 80 microg/kg to between 600 and 6000 microg/kg) while added fructose did not influence the content. The effects of temperature and time of baking were studied in another experiment using a circumscribed central composite design. Mainly temperature (above 200 degrees C) but also time increased the acrylamide content in crust dry matter (from below 10 to 1900 microg/kg), and a significant interaction was found between these two factors. When baked at different conditions with the same ingredients, a highly significant relationship (P < 0.001) between color and acrylamide content in crust was found. Added asparagine, however, did not increase color, showing that mainly other amino compounds are involved in the browning reactions.

A method using liquid chromatography tandem mass spectrometry (LC-MS-MS) with electrospray for the analysis of acrylamide in foods is reported. The method comprises the addition of deuterium-labelled acrylamide-d3, extraction with water, mixed mode solid phase extraction, ultrafiltration and a graphitised carbon column for chromatography. The transitions m/z 72 > 55, 72 > 54, 72 > 44, 72 > 27, 72 > 72 and 75 > 58 were recorded in multiple reaction monitoring mode for identification and quantification. In-house validation data for products from potatoes and cereals (30 to 10,000 microg kg(-1)) are presented (accuracy 91 to 102%, relative standard deviation 3 to 21%). Interlaboratory validation data (comparison with gas chromatography mass spectrometry, 25 to 2000 microg kg(-1)) showed excellent results (r2 = 0.998).

A method using liquid chromatography tandem mass spectrometry (LC-MS-MS) with electrospray (ES) for the determination of traces of narasin, monensin and salinomycin in chicken liver and eggs was developed, validated and used for routine surveillance. The essence of this paper is to demonstrate that one single method can serve very well for two entirely different purposes, i.e., screening and confirmation. Highly reliable confirmation of the identity at low concentrations was demonstrated when residues of narasin were detected and quantified (0.2 to 11 ng g(-1)) in 50% of the Swedish eggs analysed in 1999. Four daughter ions were detected with ion ratios meeting suggested confirmation criteria for the European Union, even at 0.2 ng g(-1). The method was found to be highly cost-effective since both screening and confirmation of 98 liver samples were performed in only two analytical runs (the Swedish national surveillance scheme of 1999, report level 5 ng g(-1)). The high performance of the method for the different applications was possible due to a combination of the power of ES-LC-MS-MS, a procedure involving screening of pooled samples, and method optimisation of the work-up (automated solid phase extraction), LC and MS parameters. Validation data for narasin (0.5 to 20 ng g(-1)) in eggs are presented (accuracy 94 to 108%, relative standard deviation 4 to 10%, limit of detection 0.026 ng g(-1)). The time for an LC-MS-MS run was 4 min, corresponding to 48 s per sample in a pool.

A new extraction method for the acetylgestagens medroxyprogesterone acetate (MPA), chloromadinone acetate and megestrol acetate, from kidney fat, has been developed. The method is a combination of matrix solid phase dispersion and solid phase extraction and is simpler and safer than previous methods, especially as it can be automated. The recovery was estimated as 59 +/- 5% (mean +/- standard deviation) for MPA. For screening purposes detection can be achieved using a commercially available enzyme immunoassay kit giving detection limits in the range of 1.0-2.0 ng g-1.

Five mouse monoclonal antibodies were raised against a recombinant protein comprising the complete sequence of gag24 protein from HTLV-IIIB. All monoclonal antibodies recognized the native protein in enzyme-linked immunosorbant assay (ELISA) and Western blots. All monoclonal antibodies also cross-reacted with an human immunodeficiency virus type 2 (HIV-2) strain in western blots, whereas only one antibody detected HIV-2 p25 in ELISA. By using synthetic peptides, cross-reacting epitopes were mapped and three regions were defined. The conserved immunogenic sites were located in the carboxyterminal region of the protein. Inhibition experiments with human sera showed that this region is also immunogenic in humans.