Immunochemical analysis of prolamins in gluten-free foods

People with coeliac disease have to maintain a gluten-free diet, which means excluding wheat, barley and rye prolamin proteins from their diet. Immunochemical methods are used to analyse the harmful proteins and to control the purity of gluten-free foods. In this thesis, the behaviour of prolamins in immunological gluten assays and with different prolamin-specific antibodies was examined. The immunoassays were also used to detect residual rye prolamins in sourdough systems after enzymatic hydrolysis and wheat prolamins after deamidation. The aim was to characterize the ability of the gluten analysis assays to quantify different prolamins in varying matrices in order to improve the accuracy of the assays. Prolamin groups of cereals consist of a complex mixture of proteins that vary in their size and amino acid sequences. Two common characteristics distinguish prolamins from other cereal proteins. Firstly, they are soluble in aqueous alcohols, and secondly, most of the prolamins are mainly formed from repetitive amino acid sequences containing high amounts of proline and glutamine. The diversity among prolamin proteins sets high requirements for their quantification. In the present study, prolamin contents were evaluated using enzyme-linked immunosorbent assays based on ω- and R5 antibodies. In addition, assays based on A1 and G12 antibodies were used to examine the effect of deamidation on prolamin proteins. The prolamin compositions and the cross-reactivity of antibodies with prolamin groups were evaluated with electrophoretic separation and Western blotting. The results of this thesis research demonstrate that the currently used gluten analysis methods are not able to accurately quantify barley prolamins, especially when hydrolysed or mixed in oats. However, more precise results can be obtained when the standard more closely matches the sample proteins, as demonstrated with barley prolamin standards. The study also revealed that all of the harmful prolamins, i.e. wheat, barley and rye prolamins, are most efficiently extracted with 40% 1-propanol containing 1% dithiothreitol at 50 °C. The extractability of barley and rye prolamins was considerably higher with 40% 1-propanol than with 60% ethanol, which is typically used for prolamin extraction. The prolamin levels of rye were lowered by 99.5% from the original levels when an enzyme-active rye-malt sourdough system was used for prolamin degradation. Such extensive degradation of rye prolamins suggest the use of sourdough as a part of gluten-free baking. Deamidation increases the diversity of prolamins and improves their solubility and ability to form structures such as emulsions and foams. Deamidation changes the protein structure, which has consequences for antibody recognition in gluten analysis. According to the resuts of the present work, the analysis methods were not able to quantify wheat gluten after deamidation except at very high concentrations. Consequently, deamidated gluten peptides can exist in food products and remain undetected, and thus cause a risk for people with gluten intolerance. The results of this thesis demonstrate that current gluten analysis methods cannot accurately quantify prolamins in all food matrices. New information on the prolamins of rye and barley in addition to wheat prolamins is also provided in this thesis, which is essential for improving gluten analysis methods so that they can more accurately quantify prolamins from harmful cereals.

Novel Mass Spectrometric Analysis Methods for Anabolic Androgenic Steroids in Sports Drug Testing

The feasibility of different modern analytical techniques for the mass spectrometric detection of anabolic androgenic steroids (AAS) in human urine was examined in order to enhance the prevalent analytics and to find reasonable strategies for effective sports drug testing. A comparative study of the sensitivity and specificity between gas chromatography (GC) combined with low (LRMS) and high resolution mass spectrometry (HRMS) in screening of AAS was carried out with four metabolites of methandienone. Measurements were done in selected ion monitoring mode with HRMS using a mass resolution of 5000. With HRMS the detection limits were considerably lower than with LRMS, enabling detection of steroids at low 0.2-0.5 ng/ml levels. However, also with HRMS, the biological background hampered the detection of some steroids. The applicability of liquid-phase microextraction (LPME) was studied with metabolites of fluoxymesterone, 4-chlorodehydromethyltestosterone, stanozolol and danazol. Factors affecting the extraction process were studied and a novel LPME method with in-fiber silylation was developed and validated for GC/MS analysis of the danazol metabolite. The method allowed precise, selective and sensitive analysis of the metabolite and enabled simultaneous filtration, extraction, enrichment and derivatization of the analyte from urine without any other steps in sample preparation. Liquid chromatographic/tandem mass spectrometric (LC/MS/MS) methods utilizing electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) were developed and applied for detection of oxandrolone and metabolites of stanozolol and 4-chlorodehydromethyltestosterone in urine. All methods exhibited high sensitivity and specificity. ESI showed, however, the best applicability, and a LC/ESI-MS/MS method for routine screening of nine 17-alkyl-substituted AAS was thus developed enabling fast and precise measurement of all analytes with detection limits below 2 ng/ml. The potential of chemometrics to resolve complex GC/MS data was demonstrated with samples prepared for AAS screening. Acquired full scan spectral data (m/z 40-700) were processed by the OSCAR algorithm (Optimization by Stepwise Constraints of Alternating Regression). The deconvolution process was able to dig out from a GC/MS run more than the double number of components as compared with the number of visible chromatographic peaks. Severely overlapping components, as well as components hidden in the chromatographic background could be isolated successfully. All studied techniques proved to be useful analytical tools to improve detection of AAS in urine. Superiority of different procedures is, however, compound-dependent and different techniques complement each other.

Imazhinist Mariengof : Dendi. Montazh. Ciniki.

The study is dedicated to the Russian poet and prose writer Anatolii Borisovich Mariengof (1897–1962). Mariengof – “the last dandy of the Republic” – was one of the leaders and main theoreticians in the poetic group of the Russian Imaginists. For his contemporaries, he was an Imaginist par excellence. His Imaginist principles – in theory and practice – are applied to the study of his first fictional novel, Cynics (1928), which served as an epilogue for his Imaginist period (1918–1928). The novel was not published in the Soviet Union until 1988. The method used in the study is a conceptual and literary historical reading, making use of the contemporary semiotic understanding of cultural mechanisms and of intertextual analysis. There are three main concepts used throughout the study: dandy, montage and catachresis. In the first chapter, the history, practice and theory of the Russian Imaginism are analyzed from the point of view of dandyism. The Imaginist theatricalisation of life is juxtaposed with the thematic analysis of their poetry, and Imaginist dandyism appears as a catachrestic category in culture. The second chapter examines the Imaginist poetic theory. It is discussed in the context of the montage principle, defining the post-revolutionary culture in Soviet Russia. The Imaginist montage can be divided into three main theoretical paradigms: S. Yesenin’s “technical montage” (reminiscent of Dadaist collage), V. Shershenevich’s “nominative montage” (catalogues of images) and Anatolii Mariengof’s “catachrestic montage”. The final chapter deals with Mariengof’s first fictional novel, Cynics. The study begins with the complex history of publication of the novel, as well as its relation to the Imaginist poetic principles and to the history of the poetic movement. Cynics is, essentially, an Imaginist montage novel. The fragmentary play of the fictional and the documentary material follows the Imaginist montage principle. The chapter concludes in a thematic analysis of the novel, concentrating on the description of the October Revolution in Cynics.

Everyday beliefs about food and health

The series of studies addresses several everyday beliefs about food and health from the perspective of everyday thinking and paranormal beliefs. They are "you are what you eat" beliefs, attitudes towards genetically modified and organic foods, and belief in alternative medicine. The survey studies included from 239 to 3261 Finnish participants. It was found that food consumption can have far-stretching consequences for the impressions of the eater in a "you are what you eat" manner. The results also demonstrated that belief in alternative medicine was related to belief in the paranormal, as were to a lesser degree attitudes towards genetically modified and organic foods. The study also addressed paranormal beliefs and belief in alternative medicine from the perspective of category observance. Paranormal believers as well as believers in alternative medicine were much more liberal than skeptics in violating categorical boundaries and attributed, for example, intentionality (mental) to body growth (biological) and life (biological) to energy (physical). In addition, the study addressed the relation of these attitudes and beliefs with preferred thinking style. The results demonstrated that belief in alternative medicine was especially appealing to intuitive thinkers, while rational thinking was unrelated to it. The same pattern was demonstrated for negative attitudes towards genetically modified food and positive attitudes towards organic food. In addition, it was demonstrated, however, that such unscientific notions may exist not instead of but parallel with "better knowledge". In sum, the present thesis contributes to the understanding of superstitious elements in various everyday attitudes and beliefs, and investigates their relationship with general inclinations towards belief in the paranormal. It appears that some very common everyday beliefs and attitudes about food and health contain elements of a superstitious nature. Involving conceptual enmeshment they go beyond mere associations, and can coincide with scientifically valid views on the same topic.

Nuorten mielikuvia kouluruokailusta

Knowledge of healthy food does not move alone our food choice. One also needs a piece of tongue evidence that food tastes good. Way to eat is part of our lifestyle. It is important to eat same foods with one`s friend. Aims: The overall aim of this study was to find out how youngsters themselves feel and sense of the school lunch, both food and whole lunch situation. This study has three specific research problems. The research problems are: 1. How the youngsters sense their school lunch events? 2. How the youngsters experience the physical conditions of their school lunch events? 3. How the youngsters think their lunch events could be changed? Methods: The data is collected in spring 2009 from two secondary school at the Kaarina city. The respondents were ninth grader. They were studying optional home economics classes. The number of respondents was 28 pupils. The respondents wrote a story, describing what kind of their school lunch situation should be. The story was based on youngsters own vision of school lunch situations. In this study the material is collected by the narrative method and the stories were analyzed with qualitative content analysis. Results and conclusions: According to the results these youngsters wanted their lunch to be more cosier and also more quiet. School lunches should be the moment when they can eat in peace and at the same talk with their friends in the pleasant surroundings. The food selection should be more varied, including both salad and main food as well as bread.