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Abstract Unfractionated heparin (UFH) is an effective antithrombotic during surgery but has known adverse effects, in particular on platelets. A marked increase in platelet responsiveness has previously been observed in patients within minutes of receiving UFH, despite adequate inhibition by aspirin prior to heparin. We studied this phenomenon in patients undergoing cardiac artery bypass grafting (n = 17) to determine whether the effects of heparin were systemic or platelet-specific. All patients’ platelets were fully inhibited by aspirin prior to surgery, but within 3 min of receiving heparin spontaneous aggregation and responses to arachidonic acid (AA) and ADP increased significantly (p ≥ 0.0002), and activated platelets were found in the circulation. While there was no rise in thromboxane in the plasma following heparin, levels of the major platelet 12-lipoxygenase product, 12-HETE, rose significantly. Mixing experiments demonstrated that the changes caused by heparin resided primarily in the platelets, while addition of AA pathway inhibitors, and analysis of oxylipins provided evidence that, following heparin, aggregating platelets regained their ability to synthesise thromboxane. These findings highlight potentially unrecognised pro-thrombotic and pro-inflammatory changes during CABG surgery, and provide further evidence of adverse effects associated with UFH.

Waste from dairy production is one of the largest sources of contamination from antimicrobial resistant bacteria (ARB) and genes (ARGs) in many parts of the world. However, studies to date do not provide necessary evidence to inform antimicrobial resistance (AMR) countermeasures. We undertook a detailed, interdisciplinary, longitudinal analysis of dairy slurry waste. The slurry contained a population of ARB and ARGs, with resistances to current, historical and never-used on-farm antibiotics; resistances were associated with Gram-negative and Gram-positive bacteria and mobile elements (ISEcp1, Tn916, Tn21-family transposons). Modelling and experimental work suggested that these populations are in dynamic equilibrium, with microbial death balanced by fresh input. Consequently, storing slurry without further waste input for at least 60 days was predicted to reduce ARB spread onto land, with > 99 % reduction in cephalosporin resistant Escherichia coli. The model also indicated that for farms with low antibiotic use, further reductions are unlikely to reduce AMR further. We conclude that the slurry tank is a critical point for measurement and control of AMR, and that actions to limit the spread of AMR from dairy waste should combine responsible antibiotic use, including low total quantity, avoidance of human critical antibiotics, and choosing antibiotics with shorter half-lives, coupled with appropriate slurry storage.

Abstract Purpose Plasma-Lyte is a balanced, crystalloid intravenous fluid which has been shown to avoid the hyperchloremic metabolic acidosis associated with 0.9% sodium chloride. Data on physical, pH and chemical compatibility with other medicines are essential. Methods The compatibility of adrenaline, dobutamine, dopamine, furosemide, midazolam, morphine and milrinone with Plasma-Lyte 148 (PLA) and Plasma-Lyte 148 with 5% glucose (PLA-G) was investigated. Control solutions were 0.9% sodium chloride and 5% glucose. Chemical stability was defined as

Omega-6 FAs are inflammatory mediators that are increased in joints with osteoarthritis (OA), but their association with OA progression is not yet well defined. To investigate the relationship between omega-6 FAs and knee OA, we measured with LC-MS the levels of 22 omega-6 lipids (arachidonic acid, linoleic acid, and 20 oxylipins) in synovial fluid (SF) from 112 knees of 102 individuals (58 with knee OA; 44 controls). We hypothesized that oxylipin metabolites would increase in OA knee SF and with radiographically progressive disease. We validated results by comparing samples from affected and unaffected knees in 10 individuals with unilateral OA. In adjusted analysis, SF levels of three omega-6 oxylipins [prostaglandin D2, 11,12-dihydroxyeicosatrienoic acid (DHET), and 14,15-DHET] were associated with OA. Of these, 11,12-DHET and 14,15-DHET were higher in affected versus unaffected knees of people with unilateral disease (P < 0.014 and P < 0.003, respectively). Levels of these and 8,9-DHET were also associated with radiographic progression over 3.3 years in 87 individuals. Circulating levels of all three were associated with gene variants at the soluble epoxide hydrolase enzyme. Lipidomic profiling in SF identified an additional inflammatory pathway associated with knee OA and radiographic progression.

Oral sesame oil-based formulation facilitates the delivery of poorly water-soluble drug cannabidiol (CBD) to the lymphatic system and blood circulation. However, this natural oil-based formulation also leads to considerable variability in absorption of CBD. In this work, the performance of lipid-based formulations with the addition of medium-chain triglyceride (MCT) or surfactants to the sesame oil vehicle has been tested in vitro and in vivo using CBD as a model drug. The in vitro lipolysis has shown that addition of the MCT leads to a higher distribution of CBD into the micellar phase. Further addition of surfactants to MCT-containing formulations did not improve distribution of the drug into the micellar phase. In vivo, formulations containing MCT led to lower or similar concentrations of CBD in serum, lymph and MLNs, but with reduced variability. MCT improves the emulsification and micellar solubilization of CBD, but surfactants did not facilitate further the rate and extent of lipolysis. Even though addition of MCT reduces the variability, the in vivo performance for the extent of both lymphatic transport and systemic bioavailability remains superior with a pure natural oil vehicle.

Abstract Background Currently available diagnostic techniques of Plasmodium falciparum infection are not optimal for non-invasive, population-based screening for malaria. It was hypothesized that a mass spectrometry-based metabolomics approach could identify urinary biomarkers of falciparum malaria. Methods The study used a case–control design, with cases consisting of 21 adults in central Ethiopia with a diagnosis of P. falciparum infection confirmed with microscopy, and 25 controls of adults with negative blood smears for malaria matched on age and sex. Urinary samples were collected from these individuals during presentation at the clinic, and a second sample was collected from both cases and controls 4 weeks later, after the cases had received anti-malarial medication. The urine samples were screened for small molecule urinary biomarkers, using mass spectrometry-based metabolomics analyses followed by multivariate analysis using principal component analysis and orthogonal partial least square-discriminant analysis. The chemical identity of statistically significant malaria biomarkers was confirmed using tandem mass spectrometry. Results The urinary metabolic profiles of cases with P. falciparum infection were distinct from healthy controls. After treatment with anti-malarial medication, the metabolomic profile of cases resembled that of healthy controls. Significantly altered levels of 29 urinary metabolites were found. Elevated levels of urinary pipecolic acid, taurine, N-acetylspermidine, N-acetylputrescine and 1,3-diacetylpropane were identified as potential biomarkers of falciparum malaria. Conclusion The urinary biomarkers of malaria identified have potential for the development of non-invasive and rapid diagnostic test of P. falciparum infection.

The integration of untargeted metabolomics and transcriptomics from the same population of cells or tissue enhances the confidence in the identified metabolic pathways and understanding of the enzyme–metabolite relationship. Here, we optimised a simultaneous extraction method of metabolites/lipids and RNA from ependymoma cells (BXD-1425). Relative to established RNA (mirVana kit) or metabolite (sequential solvent addition and shaking) single extraction methods, four dual-extraction techniques were evaluated and compared (methanol:water:chloroform ratios): cryomill/mirVana (1:1:2); cryomill-wash/Econospin (5:1:2); rotation/phenol-chloroform (9:10:1); Sequential/mirVana (1:1:3). All methods extracted the same metabolites, yet rotation/phenol-chloroform did not extract lipids. Cryomill/mirVana and sequential/mirVana recovered the highest amounts of RNA, at 70 and 68% of that recovered with mirVana kit alone. sequential/mirVana, involving RNA extraction from the interphase of our established sequential solvent addition and shaking metabolomics-lipidomics extraction method, was the most efficient approach overall. Sequential/mirVana was applied to study a) the biological effect caused by acute serum starvation in BXD-1425 cells and b) primary ependymoma tumour tissue. We found (a) 64 differentially abundant metabolites and 28 differentially expressed metabolic genes, discovering four gene-metabolite interactions, and (b) all metabolites and 62% lipids were above the limit of detection, and RNA yield was sufficient for transcriptomics, in just 10 mg of tissue.

The euphoric feeling described after running is, at least in part, due to increased circulating endocannabinoids (eCBs). eCBs are lipid signaling molecules involved in reward, appetite, mood, memory and neuroprotection. The aim of this study was to investigate whether activities other than running can increase circulating eCBs. Nine healthy female volunteers (mean 61 years) were recruited from a local choir. Circulating eCBs, haemodynamics, mood and hunger ratings were measured before and immediately after 30 min of dance, reading, singing or cycling in a fasted state. Singing increased plasma levels of anandamide (AEA) by 42% (P < 0.05), palmitoylethanolamine (PEA) by 53% (P < 0.01) and oleoylethanolamine (OEA) by 34% (P < 0.05) and improved positive mood and emotions (P < 0.01), without affecting hunger scores. Dancing did not affect eCB levels or hunger ratings, but decreased negative mood and emotions (P < 0.01). Cycling increased OEA levels by 26% (P < 0.05) and tended to decrease how hungry volunteers felt, without affecting mood. Reading increased OEA levels by 28% (P < 0.01) and increased the desire to eat. Plasma AEA levels were positively correlated with how full participants felt (P < 0.05). Plasma OEA levels were positively correlated with positive mood and emotions (P < 0.01). All three ethanolamines were positively correlated with heart rate (HR; P < 0.0001). These data suggest that activities other than running can increase plasma eCBs associated with changes in mood or appetite. Increases in eCBs may underlie the rewarding and pleasurable effects of singing and exercise and ultimately some of the long-term beneficial effects on mental health, cognition and memory.

Dyadic contests for possession of resources occur across a wide range of animal taxa, with contest outcome often being heavily influenced by the energetic reserves of the competitors. The majority of studied parasitoid wasps lack de novo lipogenesis, with adult lipid reserves being limited to those acquired throughout larval development. Carbohydrate- and lipid-rich diets can increase adult parasitoid lifespan and fecundity by potentially acting as a maintenance energy store. However, the effects of such diets on fat reserve compositions and contest outcome have not been examined. This study assesses the effects of a carbohydrate rich diet (honey) on the longevity, metabolic state and contest performance of Goniozus legneri, a bethylid wasp. The longevity of honey-fed adults was typically more than twice that of starved wasps. Compared to similarly-aged starved wasps, honey feeding increased concentrations of common haemolymph sugars and amino acids in 3-day old and 7-day old wasps, and higher concentrations of stored lipid in 7-day old wasps. However, nutritional status did not affect the outcome of dyadic contests over host possession when both contestants were either 3 days or 7 days old. While contest outcome may be unaffected by diet, it remains possible that an enhancing effect of feeding on contest ability is matched by an effect of higher value being placed on winning by starved wasps.

We describe a novel LC method for the simultaneous and quantitative profiling of 43 oxylipins including eicosanoids, endocannabinoids, and structurally related bioactive lipids with modified acyl groups. The LC-MS/MS method uses switching at a defined time between negative and positive electrospray ionization modes to achieve optimal detection sensitivity for all the lipids. The validated method is linear over a range of 0.01–5 nmol/g (0.1–50 nmol/g for 2-arachidonoyl glycerol) with intra- and interday precision and accuracy between 1.38 and 26.76% and 85.22 and 114.3%, respectively. The method successfully quantified bioactive lipids in different tissue types in the rat, including spinal cord, dorsal root ganglia (DRGs), knee joint, brain, and plasma. Distinct regional differences in the pattern of lipid measured between tissue types were observed using principle component analysis. The method was applied to analyze tissue samples from an established preclinical rat model of osteoarthritis (OA) pain and showed that levels of 12-hydroxyeicosatetraenoic acid were significantly increased in the OA rat knee joint compared with controls, and that 15-hydroxyeicosatetraenoic acid was significantly increased in the DRGs in the model of OA compared with controls. The developed LC-MS/MS method has the potential to provide detailed pathway profiling in tissues and biofluids where the disruption of bioactive oxylipins may be involved in disease states.

Aim. We examined endocannabinoids (ECs) in relation to bariatric surgery and the association between plasma ECs and markers of insulin resistance. Methods. A study of 20 participants undergoing bariatric surgery. Fasting and 2-hour plasma glucose, lipids, insulin, and C-peptide were recorded preoperatively and 6 months postoperatively with plasma ECs (AEA, 2-AG) and endocannabinoid-related lipids (PEA, OEA). Results. Gender-specific analysis showed differences in AEA, OEA, and PEA preoperatively with reductions in AEA and PEA in females postoperatively. Preoperatively, AEA was correlated with 2-hour glucose (r=0.55, P=0.01), HOMA-IR (r=0.61, P=0.009), and HOMA %S (r=-0.71, P=0.002). OEA was correlated with weight (r=0.49, P=0.03), waist circumference (r=0.52, P=0.02), fasting insulin (r=0.49, P=0.04), and HOMA-IR (r=0.48, P=0.05). PEA was correlated with fasting insulin (r=0.49, P=0.04). 2-AG had a negative correlation with fasting glucose (r=-0.59, P=0.04). Conclusion. Gender differences exist in circulating ECs in obese subjects. Females show changes in AEA and PEA after bariatric surgery. Specific correlations exist between different ECs and markers of obesity and insulin and glucose homeostasis.