ω-3 oil intake during weight loss in obese women results in remodelling of plasma triglyceride and fatty acids

Previous studies have shown that a combination of weight loss and fish oil supplementation reduce cardiovascular disease and diabetes risks by increasing adiponectin and reducing triacylglyceride concentrations, while weight loss alone significantly improves insulin sensitivity and reduces inflammation. Here, a metabolomic approach, using a combination of 1H-Nuclear Magnetic Resonance spectroscopy, and gas and liquid chromatography and mass spectrometry, was employed to elucidate the metabolic changes in blood plasma following weight loss and fish oil supplementation. The intervention study was conducted over 24 weeks, with 93 female subjects randomised to one of three groups. Two groups followed a 12-week weight loss program, followed by a 12-week weight maintenance period and were randomised to fish or placebo oil capsules; a control group did not follow the weight loss program and were given placebo oil capsules. Lipid profiles changed dramatically upon fish oil intake and subtly across the two weight loss groups. While the fish oil supplementation increased the proportion of various phospholipid species, previously reported reductions in total triacylglycerides (TAGs) upon fish oil intake were shown to be driven by a reduction in a specific subset of the measured TAGs. This remodelling of triglycerides may represent further beneficial effects of fish oil supplementation

Quantification of drug metabolising enzymes and transporter proteins in the paediatric duodenum via LC-MS/MS proteomics using a QconCAT technique

Characterising the small intestine absorptive membrane is essential to enable prediction of the systemic exposure of oral formulations. In particular, the ontogeny of key intestinal Drug Metabolising Enzymes and Transporter (DMET) proteins involved in drug disposition needs to be elucidated to allow for accurate prediction of the PK profile of drugs in the paediatric cohort. Using pinch biopsies from the paediatric duodenum (n = 36; aged 11 months to 15 years), the abundance of 21 DMET proteins and two enterocyte markers were quantified via LC-MS/MS. An established LCMS nanoflow method was translated to enable analysis on a microflow LC system, and a new stable-isotope-labelled QconCAT standard developed to enable quantification of these proteins. Villin-1 was used to standardise abundancy values. The observed abundancies and ontogeny profiles, agreed with adult LC-MS/MS-based data, and historic paediatric data obtained via western blotting. A linear trend with age was observed for duodenal CYP3A4 and CES2 only. As this work quantified peptides on a pinch biopsy coupled with a microflow method, future studies using a wider population range are very feasible. Furthermore, this DMET ontogeny data can be used to inform paediatric PBPK modelling and to enhance the understanding of oral drug absorption and gut bioavailability in paediatric populations

Individualised variable-interval risk-based screening for sight-threatening diabetic retinopathy: the Liverpool Risk Calculation Engine

Aims/hypothesis Individualised variable-interval risk-based screening offers better targeting and improved cost-effectiveness in screening for diabetic retinopathy. We developed a generalisable risk calculation engine (RCE) to assign personalised intervals linked to local population characteristics, and explored differences in assignment compared with current practice. Methods Data from 5 years of photographic screening and primary care for people with diabetes, screen negative at the first of > 1 episode, were combined in a purpose-built near-real-time warehouse. Covariates were selected from a dataset created using mixed qualitative/quantitative methods. Markov modelling predicted progression to screen-positive (referable diabetic retinopathy) against the local cohort history. Retinopathy grade informed baseline risk and multiple imputation dealt with missing data. Acceptable intervals (6, 12, 24 months) and risk threshold (2.5%) were established with patients and professional end users. Results Data were from 11,806 people with diabetes (46,525 episodes, 388 screen-positive). Covariates with sufficient predictive value were: duration of known disease, HbA1c, age, systolic BP and total cholesterol. Corrected AUC (95% CIs) were: 6 months 0.88 (0.83, 0.93), 12 months 0.90 (0.87, 0.93) and 24 months 0.91 (0.87, 0.94). Sensitivities/specificities for a 2.5% risk were: 6 months 0.61, 0.93, 12 months 0.67, 0.90 and 24 months 0.82, 0.81. Implementing individualised RCE-based intervals would reduce the proportion of people becoming screen-positive before the allocated screening date by > 50% and the number of episodes by 30%. Conclusions/interpretation The Liverpool RCE shows sufficient performance for a local introduction into practice before wider implementation, subject to external validation. This approach offers potential enhancements of screening in improved local applicability, targeting and cost-effectiveness

Initial Public Offerings and the Firm Location

The firm geographic location matters in IPOs because investors have a strong preference for newly issued local stocks and provide abnormal demand in local offerings. Using equity holdings data for more than 53,000 households, we show the probability to participate to the stock market and the proportion of the equity wealth is abnormally increasing with the volume of the IPOs inside the investor region. Upon nearly the universe of the 167,515 going public and private domestic manufacturing firms, we provide consistent evidence that the isolated private firms have higher probability to go public, larger IPO underpricing cross-sectional average and volatility, and less pronounced long-run under-performance. Similar but opposite evidence holds for the local concentration of the investor wealth. These effects are economically relevant and robust to local delistings, IPO market timing, agglomeration economies, firm location endogeneity, self-selection bias, and information asymmetries, among others. Findings suggest IPO waves have a strong geographic component, highlight that underwriters significantly under-estimate the local demand component thus leaving unexpected money on the table, and support state-contingent but constant investor propensity for risk

A metabolomic and multivariate statistical process to assess the effects of genotoxins in Saccharomyces cerevisiae

There is an increased need to develop robust cellular model systems which could replace or reduce the need for animals in toxicological testing. Current in vitro strategies for genotoxicity testing suffer from a high irrelevant positive rate, requiring the need for the development of new in vitro tools. Saccharomyces cerevisiae is used widely to study DNA damage and repair, and a high-throughput green fluorescent protein based assay has been developed to detect genotoxic-induced DNA damage. In this study a combined high resolution H-1 NMR spectroscopy and gas chromatography mass spectrometry based metabolomic approach has been used to monitor and distinguish different genotoxic compounds from other types of toxic lesion using the multivariate classification tool partial least squares-discriminate analysis (PLS-DA). The metabolic profiles of extracts of yeast (W303 alpha strain) readily distinguished the individual toxins from control cells across 22 different treatments. In addition, these metabolic profiles also demonstrated dose and time responses for selected compounds (methyl methane sulfonate and nocodazole). Finally, predictive models were built for distinguishing the genotoxic carcinogens from the control group according to the metabolic profile of the cell culture media

Multi-residue determination of anticoagulant rodenticides in vertebrate wildlife and domestic animals using Ultra (High) Performance Liquid Chromatography Tandem Mass Spectrometry

Anticoagulant rodenticide (AR) products are used globally to control rodent pests in domestic, urban, agricultural and industrial environments. However, there is a substantial volume of evidence that non-target vertebrate wildlife i.e. predators and scavengers in particular and other animals, are vulnerable to contamination via direct or indirect routes of exposure. The determination of multiple AR residues in liver tissue samples that can range from remnants of a small bird of prey liver to an intact liver from a large mammal is complicated as residue levels encountered can vary considerably too. So, the utilisation of ultra-sensitive systems has to be carefully considered in order to allow routine application of the method to all sample compositions presented for analysis. The UHPLC–MSMS method described now: • permits quantitative analysis of ultra-low levels of multiple-residues (0.0025–1 mg kg−1) in a single experiment. • uses the same U(H)PLC column for the determination of AR and multiple-pesticide residue in similar specimens. • allows higher sample throughput due to shaking rather than tumbling of samples during the extraction procedure. Method name: An improved multi-residue method for the determination of 9 anticoagulant rodenticides in liver tissue from non-target vertebrate wildlife and domestic animals using Ultra (High) Performance Liquid Chromatography Tandem Mass Spectrometry (UHPLC–MSMS), Keywords: Anticoagulant rodenticides, UHPLC–MSMS, multi-residues, GPC clean-up, live

Guilty by Dissociation: Part A: Development of a rapid Ultra-High Performance Liquid Chromatography (UHPLC)-MS/MS methodology for the analysis of regioisomeric diphenidine-derived Novel Psychoactive Substances (NPS)

This study describes the first reported development of a rapid, generic gradient Ultra-High Performance Liquid Chromatography (UHPLC) methodology with targeted triple quadrupole MS/MS using electrospray positive ionisation to detect and unambiguously confirm the identity of 33 substituted 1, 2-diarylethamine (or diphenidine) derivatives in solid drug samples. The in-house synthesised library included a range of derivatives possessing either electron donating/withdrawing substituents, commonly included in combinatorial libraries, of varying size and lipophilicity on the phenyl ring. These test probes were used to investigate if their order of elution and that of their regioisomers were dependent on the position and type of the substituent on the phenyl ring. In addition, investigations into the retention mechanism of the diphenidines under reverse-phase UHPLC conditions were undertaken. Common adulterants found within seized bulk samples were assessed to prove that the methodology was specific, and the developed UHPLC-MS/MS (tG = 10 min) protocol was applied to confirm the identity of the psychoactive components within two seized bulk samples provided by law enforcement