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Aims: Heterogeneity in the rate of β‐cell loss in newly diagnosed type 1 diabetes patients is poorly understood and creates a barrier to designing and interpreting disease‐modifying clinical trials. Integrative analyses of baseline multi‐omics data obtained after the diagnosis of type 1 diabetes may provide mechanistic insight into the diverse rates of disease progression after type 1 diabetes diagnosis. Methods: We collected samples in a pan‐European consortium that enabled the concerted analysis of five different omics modalities in data from 97 newly diagnosed patients. In this study, we used Multi‐Omics Factor Analysis to identify molecular signatures correlating with post‐diagnosis decline in β‐cell mass measured as fasting C‐peptide. Results: Two molecular signatures were significantly correlated with fasting C‐peptide levels. One signature showed a correlation to neutrophil degranulation, cytokine signalling, lymphoid and non‐lymphoid cell interactions and G‐protein coupled receptor signalling events that were inversely associated with a rapid decline in β‐cell function. The second signature was related to translation and viral infection was inversely associated with change in β‐cell function. In addition, the immunomics data revealed a Natural Killer cell signature associated with rapid β‐cell decline. Conclusions: Features that differ between individuals with slow and rapid decline in β‐cell mass could be valuable in staging and prediction of the rate of disease progression and thus enable smarter (shorter and smaller) trial designs for disease modifying therapies as well as offering biomarkers of therapeutic effect. [ABSTRACT FROM AUTHOR]

Insulin resistance is a forerunner state of ischaemic cardiovascular disease and type 2 diabetes. Here we show how the human gut microbiome impacts the serum metabolome and associates with insulin resistance in 277 non-diabetic Danish individuals. The serum metabolome of insulin-resistant individuals is characterized by increased levels of branched- chain amino acids (BCAAs), which correlate with a gut microbiome that has an enriched biosynthetic potential for BCAAs and is deprived of genes encoding bacterial inward transporters for these amino acids. Prevotella copri and Bacteroides vulgatus are identified as the main species driving the association between biosynthesis of BCAAs and insulin resistance, and in mice we demonstrate that P. copri can induce insulin resistance, aggravate glucose intolerance and augment circulating levels of BCAAs. Our findings suggest that microbial targets may have the potential to diminish insulin resistance and reduce the incidence of common metabolic and cardiovascular disorders., Insulin resistance (IR) and metabolic syndrome are risk factors for both type 2 diabetes and ischaemic cardiovascular diseases, pathologies that are in epidemic growth worldwide. Mounting evidence suggests a link [...]

A new method, purge-and-membrane mass spectrometry (PAM MS), is introduced for the analysis of volatile organic compounds (VOCs) in water and soil samples. In this method, VOCs are purged from water or soil samples with an inert gas and the stream is directed through a sheet membrane module. The VOCs pervaporate through the membrane directly into the ion source of a mass spectrometer. The limits of detection for nonpolar VOCs such as halogenated hydrocarbons, benzene, toluene, and xylenes were below micrograms per liter in water samples and at low micrograms per kilogram levels in soil samples. The correlation coefficients measured for the compounds studied were typically better than 0.9999 and 0.9975 in water and sod samples, respectively. The relative standard deviations were between 0.5 and 2.0% with water samples and between 4.8 and 14.0% with soil samples. These results demonstrate excellent linearity and repeatability. PAM MS thus provides a highly sensitive, selective, accurate, solvent-free, and rapid analytical method. Tens of samples can be analyzed reliably within 1 h.

Abstract Background The mechanism behind the lowered postprandial insulin demand observed after rye bread intake compared to wheat bread is unknown. The aim of this study was to use the metabolomics approach to identify potential metabolites related to amino acid metabolism involved in this mechanism. Methods A sourdough fermented endosperm rye bread (RB) and a standard white wheat bread (WB) as a reference were served in random order to 16 healthy subjects. Test bread portions contained 50 g available carbohydrate. In vitro hydrolysis of starch and protein were performed for both test breads. Blood samples for measuring glucose and insulin concentrations were drawn over 4 h and gastric emptying rate (GER) was measured. Changes in the plasma metabolome were investigated by applying a comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry metabolomics platform (GC×GC-TOF-MS). Results Plasma insulin response to RB was lower than to WB at 30 min (P = 0.004), 45 min (P = 0.002) and 60 min (P < 0.001) after bread intake, and plasma glucose response was significantly higher at time point 90 min after RB than WB intake (P = 0.045). The starch hydrolysis rate was higher for RB than WB, contrary to the in vitro protein digestibility. There were no differences in GER between breads. From 255 metabolites identified by the metabolomics platform, 26 showed significant postprandial relative changes after 30 minutes of bread intake (p and q values < 0.05). Among them, there were changes in essential amino acids (phenylalanine, methionine, tyrosine and glutamic acid), metabolites involved in the tricarboxylic acid cycle (alpha-ketoglutaric, pyruvic acid and citric acid) and several organic acids. Interestingly, the levels of two compounds involved in the tryptophan metabolism (picolinic acid, ribitol) significantly changed depending on the different bread intake. Conclusions A single meal of a low fibre sourdough rye bread producing low postprandial insulin response brings in several changes in plasma amino acids and their metabolites and some of these might have properties beneficial for health.

Three genes were cloned and expressed in Trichoderma reesei to identify novel cutinolytic polyesterases that could be exploited in treating agricultural, food, and forest raw materials as well as their processing by-products. The results from the microscopic analyses and determination of released hydrolysis products showed that the enzyme cutinolytic polyesterases was able to depolymerize apple cutin and birch outer bark suberin.

Purge-and-membrane mass spectrometry (PAM-MS) is a combination of dynamic headspace sampling and membrane extraction. A new and simple purge-and-membrane sampler is introduced and its basic testing results for the analysis of VOCs in soil samples are reported. Soil moisture had no effect on desorption times in the case of sand, but the desorption times increased when the content of organic matter in the soil sample (garden soil) increased. The longest desorption times were measured with dry garden soil samples. For both types of samples, minor differences in desorption peak areas were observed between 10 and 20% moisture. Detection limits of the VOCs varied in the range 2-150 [micro]g/kg, depending on the soil type. Good linearity (correlation coefficient [is greater than] 0.990) was observed in the range 0.5-50 mg/kg. Aging of the spiked soil samples had only a slight effect on desorption peak areas for samples stored at 5 [degrees] C up to two weeks, but after six months of storing, differences were observed between dry sand and moistened garden soil. In both cases, peak areas were diminished. On average, 46% of compounds could be desorbed from the aged sand and 86% from the aged garden soil. The modified vapor fortification method was used in preparing standard soil samples, which were analyzed by static headspace gas chromatography (HSGC) and PAM-MS. Some authentic soil samples were also analyzed using both of these techniques. Many of the vapor fortification samples and the authentic samples were also analyzed in another laboratory by HSGC. The agreement between the methods and the laboratories was generally good.