Detection Technologies. Ambient mass spectrometry

A recent innovation in mass spectrometry is the ability to record mass spectra on ordinary samples, in their native environment, without sample preparation or preseparation by creating ions outside the instrument. In desorption electrospray ionization (DESI), the principal method described here, electrically charged droplets are directed at the ambient object of interest; they release ions from the surface, which are then vacuumed through the air into a conventional mass spectrometer. Extremely rapid analysis is coupled with high sensitivity and high chemical specificity. These characteristics are advantageously applied to high-throughput metabolomics, explosives detection, natural products discovery, and biological tissue imaging, among other applications. Future possible uses of DESI for in vivo clinical analysis and its adaptation to portable mass spectrometers are described.     

Chondrosarcoma in a simmental cow: Clinical, ultrasonographic, radiographic and pathological findings

Clinical, ultrasonographic, radiographic and pathological findings of a chondrosarcoma diagnosed in an 8-year-old Simmental cow are reported. The primary site was located in the cartilage of the right scapula at the angulus cranialis. The tumour had already spread to the lungs at the time of diagnosis. This is the first report of a bovine scapula chondrosarcoma.     

Spectroscopic analysis of diversity of Arabinoxylan structures in endosperm cell walls of wheat cultivars (Triticum aestivum) in the HEALTHGRAIN diversity collection

Fifty bread wheat (Triticum aestivum L.) cultivars were selected from the HEALTHGRAIN germplasm collection based on variation in their contents of total and water-extractable arabinoxylan. FT-IR spectroscopic mapping of thin transverse sections of grain showed variation in cell wall arabinoxylan composition between the cultivars, from consisting almost entirely of low-substituted arabinoxylan (e.g., T.aestivum 'Claire') to almost entirely of highly substituted arabinoxylan (e.g., T.aestivum 'Manital') and a mixture of the two forms (e.g., T.aestivum 'Hereward'). Complementary data were obtained using endoxylanase digestion of flour followed by HP-AEC analysis of the arabinoxylan oligosaccharides. This allowed the selection of six cultivars for more detailed analysis using FT-IR and (1)H NMR spectroscopy to determine the proportions of mono-, di-, and unsubstituted xylose residues. The results of the two analyses were consistent, showing that variation in the composition and structure of the endosperm cell wall arabinoxylan is present between bread wheat cultivars. The heterogeneity and spatial distribution of the arabinoxylan in endosperm cell walls may be exploited in wheat processing as it may allow the production of mill streams enriched in various arabinoxylan fractions which have beneficial effects on health.     

Effect of broth from meat of linseed‐fed cattle on glucose‐stimulated insulin release in healthy male volunteers

Polyunsaturated fatty acid consumption has been shown to improve insulin sensitivity. We studied if administration of broth with beef meat enriched with polyunsaturated fatty acids influenced glucose‐stimulated insulin release in healthy male volunteers. Broth was made either from cattles undergone dietary supplementation with lightly bruised whole linseed in addition to feeding ad libitum on grass silage (test meal) or from those fed grass silage alone (control meal). Oral glucose tolerance tests (OGTT) were performed in patients after a 6‐day period of eating 300 ml broth containing 100 g meat once a day in addition to their otherwise normal mixed nourishment. During OGTT, blood samples were taken for blood glucose level and plasma insulin immunoreactivity before and 15, 30, 60, 90, 120, and 180 min after the glucose load. Glucose‐stimulated maximum increase in plasma insulin immunoreactivity was 42 ± 6.6 and 81 ± 7.4 mU/ml (p < 0.05) after the test and the control meals, respectively. However, both fasting and postload blood glucose levels were the same after either meal period. The results suggest an insulin‐sensitizing effect of food produced from beef cattle maintained on linseed diet in healthy human volunteers.     

Temperature-sensitive wheat stem rust resistance gene Sr15 is effective against Puccinia graminis f. sp. tritici race TTKSK

The wheat stem rust fungus, Puccinia graminis f. sp. tritici (Pgt), race TTKSK and related races pose a serious threat to world wheat production. Knowing the effectiveness of wheat stem rust resistance (Sr) genes against Pgt race TTKSK is fundamental in mitigating this threat through resistance breeding. Sr15 was previously identified as being ineffective against Pgt race TTKSK. Here, multirace disease phenotyping data, linkage analyses, allelism testing and haplotype analyses are presented to support the conclusion that Sr15 is effective against Pgt race TTKSK. Resistance to race TTKSK was mapped to Sr15 in a biparental population. Thirty-two accessions with Sr15 displayed seedling resistance phenotypes against race TTKSK. However, these accessions were susceptible as seedlings at high temperatures (22–25 °C), consistent with previous reports that the interaction between avirulent Pgt isolates and Sr15 is temperature-sensitive. Markers STS638, wri4 and KASP_IWB30995 were found to predict the presence of Sr15, suggesting the utility of these assays for marker-assisted selection in breeding programmes. The effectiveness of Sr15 to specific Pgt races and temperatures makes it a less-desirable TTKSK-effective gene. Wheat lines assayed as resistant to race TTKSK at the seedling stage may possess Sr15 and breeders should be aware of the limitations of Sr15 for conferring stem rust resistance.     

Relationship between the contents of bioactive components in grain and the release dates of wheat lines in the HEALTHGRAIN diversity screen

The EU FP6 HEALTHGRAIN has generated an extensive database on the contents of phytochemicals (alkylresorcinols, tocols, sterols, phenolic acids, folates) and dietary fiber components in the grain of wheat, including analyses of 150 lines grown on a single site in Hungary in 2005 and a smaller set of lines grown under five (three lines) or six (23 lines) different environments (in Hungary in 2005, 2006, and 2007 and in France, Poland, and the United Kingdom in 2007). The lines analyzed included land races and varieties bred between the mid-19th and early 21st centuries. These results have been analyzed to determine whether the contents of these groups of bioactive components in the grain have decreased with the development of intensive plant breeding in the second part of the 20th century. No decreases in the contents of any groups of bioactive components were observed in relation to release date, showing that selection for increased yield and protein quality has been effectively neutral for other grain components.     

Potential Dissipation of Atrazine in the Soil Unsaturated Zone: a Comparative Study in Four European Countries

A European-wide project has been undertaken to establish the potential for dissipation of atrazine in the soil subsurface environment. Samples were obtained, avoiding contamination, in four countries (Belgium, Greece, Hungary and UK) and laboratory studies carried out. In order to make comparisons between results from each laboratory, a ring experiment was carried out using common methodology for sampling, extraction and analytical techniques. Subsurface materials from each country were distributed to the other countries. Atrazine dissipation was determined in each country for all materials under the same laboratory conditions. The results of this comparative study showed generally good agreement between all laboratories. Significant potential microbiological dissipation was detected in certain samples. Where differences occurred between laboratories this was attributed to small, spatially heterogeneous microbial populations in the subsurface materials. © 1997 SCI.     

Variation in mineral micronutrient concentrations in grain of wheat lines of diverse origin

150 lines of bread wheat representing diverse origin and 25 lines of durum, spelt, einkorn and emmer wheat species were analysed for variation in micronutrient concentrations in grain. A subset of 26 bread wheat lines was grown at six sites or seasons to identify genetically determined differences in micronutrient concentrations. Substantial variation among the 175 lines existed in grain Fe, Zn and Se concentrations. Spelt, einkorn and emmer wheats appeared to contain higher Se concentration in grain than bread and durum wheats. Significant differences between bread wheat genotypes were found for grain Fe and Zn, but not Se concentration; the latter was influenced more by the soil supply. Grain Zn, but not Fe, concentration correlated negatively with grain yield, and there was a significant decreasing trend in grain Zn concentration with the date of variety release, suggesting that genetic improvement in yield has resulted in a dilution of Zn concentration in grain. Both grain Zn and Fe concentrations also correlated positively and significantly with grain protein content and P concentration, but the correlations with kernel size, kernel weight or bran yield were weak. The results from this study are useful for developing micronutrient biofortification strategies.     

Strength properties of black spruce wood under different treatment

Summary The effect of various forms of treatment — chemical, thermal and pressure — on the tensile properties of wood was investigated. Spruce was impregnated in water, sodium sulfite and/or sodium bicarbonate, and heated at temperatures ranging from 20 to 190 °C. At the end of cooking (190 °C), decompression was applied both slowly and suddenly.A rise in temperature, an increase in heating time, from 4 to 10 min. at 190 °C, as well as fast pressure release influenced the tensile strength. The chemical treatment resulted in lignin sulfonation while carboxylation produced fiber swelling and, consequently, tensile strength decreased.The authors wish to thank the FCAR (Québec), NSERC (Canada) and Stake Tech. Co. for their financial support