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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

The molecular and antigenic structure of the major house dust mite allergen Der p 2 /

Mueller, Geoffrey Andrew. January 1998 (has links)
Thesis (Ph. D.)--University of Virginia, 1998. / Spine title: Molecular structure of Der p 2. Includes bibliographical references (p. 147-167). Also available online through Digital Dissertations.
32

Cloning, disruption and characterisation of Aspergillus fumigatus allergen proteases and their effect on airway epithelial cells

Farnell, Edward John January 2011 (has links)
Allergen proteases from a number sources including the filamentous fungus A. fumigatus, are thought to be important in the development of severe asthma through protease dependent interactions with the respiratory epithelium. The first aim of the thesis was to determine the effect of a variety of growth substrates on the secretion of proteases from different strains of A. fumigatus. The second aim was to investigate the effects of recombinant allergen proteases Asp f 5 and Asp f 13 expressed in the P. pastoris protein expression system and crude A. fumigatus culture supernatants on airway epithelial cells and determine whether protease induced interleukin 8 (IL-8) release from airway epithelial cells was dependent on the activation of protease activated receptor 2 (PAR-2).Results demonstrated that the AF293 strain of A. fumigatus secreted serine proteases during growth on pig lung homogenate medium and metalloproteases during growth on a casein based medium but suppressed protease secretion in Vogel's minimal medium. Analysis of the secretion and RNA levels of proteases in A. fumigatus showed that the matrix metalloprotease, Asp f 5 and the serine protease, Asp f 13 were up-regulated and secreted during growth in pig lung medium and that the matrix metalloprotease, Lap1 was up-regulated and secreted along with Asp f 5 and Asp f 13 in casein medium. This finding was confirmed using protease inhibitors and by using strains of A. fumigatus in which Asp f 5 and Asp f 13 genes were disrupted. These results suggest that A. fumigatus was able to detect different complex proteins available as substrates in its environment and regulate protease secretion accordingly. Furthermore, in several strains of A. fumigatus, protease activity was not suppressed by growth in Vogel's medium, suggesting differences in the regulation of protease secretion between strains. Both A. fumigatus culture supernatants and recombinant Asp f 5 and Asp f 13 produced in P. pastoris caused epithelial airway cell desquamination, and IL-8 release in a protease and dose-dependent manner. In addition, both recombinant Asp f 5 and Asp f 13 were both shown to cleave PAR-2 at a site that resulted in receptor activation.In conclusion, differences in the secretion of proteases between A. fumigatus strains and during growth of A. fumigatus on different media suggests a requirement for the standardisation of the preparation of A. fumigatus allergen extracts used both in clinical diagnosis of A. fumigatus allergy and in vitro and in vivo research studies. Furthermore, it is proposed that allergen proteases secreted by A. fumigatus may interact with a variety of host proteins including, matrix molecules, enzymes and receptors which may exacerbate allergic airway diseases.
33

Isolation and Characterization of the Crossreactive Antigenic and Allergenic Components in Callistemon Citrinis and Melaleuca Quinquenervia Pollen by Immunochemical Methods

Stanaland, Brett E. 01 January 1985 (has links) (PDF)
No description available.
34

Longitudinal Analysis of the effect of meteorological factors, allergens, and air pollution on respiratory condition in children

Song, Yunna 09 1900 (has links)
<p> In this report we explore how the effect of meteorological factors, allergens, and air pollution on respiratory conditions in children using longitudinal data. Our analysis makes use of a dataset from the DAVIS study in southern Ontario. The response variables are children's lower respiratory tract (URT) and upper respiratory tract (URT) scores. The explanatory variables are readings of various meteorological, allergen, and air pollution factors. First we make use of generalized estimating equations to find the main factors that are associated with certain respiratory conditions in children as measured by LRT and URT scores. Then we determine whether there are any interactions between the significant factors associated with LRT /URT scores. Comparisons between case and control groups are made to determine whether children with asthma are more sensitive to any of the changes in meteorological, allergen, and air pollution factors. The analysis results show that the significant factor that is associated with LRT scores for children with asthma is the two-day lag daily average changes in air pressure. On average an increase in air pressure will result in an increase in children's LRT scores. The interaction terms that remained in the final model show some degree of significance but without strong evidence to support it. Children in the case groups are more sensitive to meteorological factors, allergens, and air pollution than the children in control groups. </p> / Thesis / Master of Science (MSc)
35

Effect of diesel exhaust particles on allergic reactions and airway responsiveness in ovalbumin-sensitized brown Norway rats

Dong, Caroline. January 2007 (has links)
Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains xi, 118 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 98-118).
36

Identificação de novos alérgenos de pólen do cajueiro (Anacardium occidentale L.) para auxílio no diagnóstico e futura otimização do tratamento / Identification of novel allergens of cashew pollen

Figo, Daniele Danella 28 June 2017 (has links)
A polinose é uma rinite alérgica sazonal que acontece pela sensibilização por pólens. Possui periodicidade anual, repetindo-se os sintomas sempre na mesma época do ano. Clinicamente, é caracterizada por rinoconjuntivite e/ou asma brônquica. A imunoterapia alérgeno-específica é o único tratamento capaz de modificar a evolução natural da doença, porém, depende fundamentalmente da correta identificação do alérgeno responsável. Diante disso e do número de pacientes que procuram o Ambulatório de Alergia da Universidade de Fortaleza com manifestações alérgicas exacerbadas na época de floração do cajueiro, o objetivo deste estudo foi produzir um extrato protéico a partir do pólen do cajueiro e identificar os alérgenos ainda não estudados presentes neste pólen. Doze pacientes residentes em Fortaleza, Nordeste do país, foram selecionados com base na história de rinite alérgica persistente e agravamento dos sintomas no momento da floração do cajueiro. Foi selecionado outro grupo com rinite alérgica que vive na mesma região, entretanto não apresenta relação clínica com a época de floração. Além disso, foram incluídos 5 indivíduos não-atópicos e expostos ao cajueiro como grupo controle. O soro desses pacientes foi testado em Western Blot 1D e 2D (WB) e as proteínas selecionadas foram submetidas à espectrometria de massas para identificação. Os epitopos foram preditos in silico pesquisando sequências detectadas por massa contra bases de dados de epítopos já conhecidos. Foi possível identificar alguns homólogos de alérgenos de outros pólens, como isoflavona redutase (Bet v 6), beta-1,3-glucanase (Ole e 9), proteína de choque térmico 70kDa (Cor a 10), além de outras proteínas que podem representar novos alergénios, tais como aminociclase, glutamina sintetase, fosfoglucomutase, ?-1,4-glucano-proteína-sintase, factor de alongamento 2 e biotina carboxilase, entre outros. A predição de epítopos revelou a possibilidade de reatividade cruzada com outros alérgenos de pólen conhecidos, tais como Phl p 4, Mal d 1, além de outros aeroalérgenos que também apareceram. Esta é a primeira descrição da alergia ao pólen do caju mostrando a reatividade específica de IgE no soros dos pacientes. A caracterização imunológica e estrutural de novos alérgenos, além de auxiliar no diagnóstico e tratamento de alergias não descritas, oferece ferramentas para prever epítopos e produzir moléculas hipoalergênicas nesta era da medicina de precisão / Pollinosis is a seasonal allergic rhinitis that develops due to pollens sensitization. Symptoms are manifested always in the same period of the year. Clinically, it is characterized by rhinoconjunctivitis and/or asthma. Allergen-specific immunotherapy is the only available treatment that can modify the natural course of the disease, however, it relies on the correct identification of the triggering allergen. Considering this and the number of patients attending the Allergy Clinic at University of Fortaleza with exacerbation of allergic symptoms during cashew flowering period, the aim of this study was to produce a protein extract from cashew tree pollen and identify the allergens not yet studied. Twelve patients living in Fortaleza, Northeast of country, were selected based on history of persistent allergic rhinitis and aggravation of symptoms at the time of cashew tree flowering. Another group living in the same region with allergic rhinitis without clinical relation with the flowering season was selected. Also 5 non-atopic subjects exposed to cashew tree were selected as a control group. The serum of these patients was tested for 1D and 2D Western Blotting (WB) and selected proteins were submitted to mass spectrometry for identification. Epitopes were predicted by in silico search comparing detected sequences against epitope databases. It was possible to identify some homologs of allergens from other pollens such as isoflavone reductase (Bet v 6), beta-1,3-glucanase (Ole e 9), heat shock protein 70kDa (Cor a 10), besides other proteins that might represent novel allergens, such aminociclase, glutamina sintetase, phosphoglucomutase, alpha-1,4-glucan-protein-synthase, elongation factor 2 and biotin carboxylase among others. The epitope prediction revealed the possibility of cross-reactivity with other known pollen allergens such as Phl p 4, Mal d 1 and other aeroallergens also appeared. This is the first description of cashew pollen allergy showing specific IgE reactivity of patients\' sera. The immunological and structural characterization of new allergens, besides aiding the diagnosis and treatment of non-described allergies, offers tools for predicting epitopes and producing hypoallergenic molecules in this era of precision medicine
37

Eosinophils and eosinophilic chemokines in asthma and the effect of inhaled corticosteroids

Feltis, Bryce Nathan, 1975- January 2003 (has links)
Abstract not available
38

Modulation of the allergen-specific Tcell response

Gardner, Leanne M. (Leanne Margaret), 1977- January 2003 (has links)
Abstract not available
39

Evaluation of cleaning procedures for allergen control in a food industry environment

Wang, Xin (Annie) January 2007 (has links)
Tegel Foods Limited produces an extensive range of poultry products which may contain various potential allergens. These include wheat, soy, milk, and egg, sometimes in combination. This research has two purposes. One was to examine three cleaning stages of processing equipments – Rinse only, Foam and rinse and Sanitise and rinse to validate the efficacy of cleaning required between production runs where the first but not the second product contains the allergen. The allergen chosen to model the cleaning efficacy was gliadin, a protein in wheat. The second aim was to quantify allergenic risk to consumers from inadequately cleaned conveyer surfaces. The commercial motives driving this research were as follows. Cleaning represents a loss in productivity and an increase in consumables costs, and if it can be minimised, this would be advantageous. The requirement to declare the possibility of cross-contamination on retail packaging can potentially adversely affect consumer response, and if these declarations can be avoided then this too would be a commercial advantage. Three approaches were adopted or developed, an ATP bioluminescence test, an ELISA test kit for gliadin, and a Coomassie Blue test to quantify protein given that most allergens are proteins. Fifteen trials were done in the High Care Zone and the Old Further Processing line of the Tegel Henderson Plant production area over a period of nine months. In a typical trial, gliadin values normalised to Uncleaned values fell from 1000 (Uncleaned) arbitrary units, to 60 (Rinse only), to 0.3 (Foam and rinse), to zero (Sanitise and rinse). Parallel ATP tests similarly showed a progressive decrease in values. Compared with Uncleaned, the relative gliadin value was less than the relative ATP value after Foam and rinse in 14 of 14 trials. After Sanitise and rinse the same result was obtained. In the equivalent trials with ATP and Coomassie Blue, after cleaning of Foam and rinse and Sanitise and rinse, the relative ATP values exceeded the relative Coomassie Blue values in four of the five trials. Therefore the considerably cheaper and simpler ATP test is not only an indicator of hygiene but also a good guide to gliadin concentration (gliadin test), and to allergen contamination in general on the basis that allergens are mostly proteins (Coomassie Blue). Modelling of second-product contamination has been done, and was based on knowledge of the absolute gliadin concentration on a typical Uncleaned conveyer surface, as established in the first part of this project. The concept of the worst-case scenario examined the highest possible risk that a sensitive consumer would be exposed to an allergenic dose of gliadin. A pickup efficiency fraction of 0.3 was assumed as an upper limit of contamination from conveyer to the surface of a previously uncontaminated chicken piece. The model showed that the highest concentration of gliadin on the second product would be 6.3 ppm which is below the legislated limit of low-gluten. Information of direct commercial interest to Tegel has been extracted from all these results, and suggestions for future research have been made.
40

Evaluation of cleaning procedures for allergen control in a food industry environment

Wang, Xin (Annie) January 2007 (has links)
Tegel Foods Limited produces an extensive range of poultry products which may contain various potential allergens. These include wheat, soy, milk, and egg, sometimes in combination. This research has two purposes. One was to examine three cleaning stages of processing equipments – Rinse only, Foam and rinse and Sanitise and rinse to validate the efficacy of cleaning required between production runs where the first but not the second product contains the allergen. The allergen chosen to model the cleaning efficacy was gliadin, a protein in wheat. The second aim was to quantify allergenic risk to consumers from inadequately cleaned conveyer surfaces. The commercial motives driving this research were as follows. Cleaning represents a loss in productivity and an increase in consumables costs, and if it can be minimised, this would be advantageous. The requirement to declare the possibility of cross-contamination on retail packaging can potentially adversely affect consumer response, and if these declarations can be avoided then this too would be a commercial advantage. Three approaches were adopted or developed, an ATP bioluminescence test, an ELISA test kit for gliadin, and a Coomassie Blue test to quantify protein given that most allergens are proteins. Fifteen trials were done in the High Care Zone and the Old Further Processing line of the Tegel Henderson Plant production area over a period of nine months. In a typical trial, gliadin values normalised to Uncleaned values fell from 1000 (Uncleaned) arbitrary units, to 60 (Rinse only), to 0.3 (Foam and rinse), to zero (Sanitise and rinse). Parallel ATP tests similarly showed a progressive decrease in values. Compared with Uncleaned, the relative gliadin value was less than the relative ATP value after Foam and rinse in 14 of 14 trials. After Sanitise and rinse the same result was obtained. In the equivalent trials with ATP and Coomassie Blue, after cleaning of Foam and rinse and Sanitise and rinse, the relative ATP values exceeded the relative Coomassie Blue values in four of the five trials. Therefore the considerably cheaper and simpler ATP test is not only an indicator of hygiene but also a good guide to gliadin concentration (gliadin test), and to allergen contamination in general on the basis that allergens are mostly proteins (Coomassie Blue). Modelling of second-product contamination has been done, and was based on knowledge of the absolute gliadin concentration on a typical Uncleaned conveyer surface, as established in the first part of this project. The concept of the worst-case scenario examined the highest possible risk that a sensitive consumer would be exposed to an allergenic dose of gliadin. A pickup efficiency fraction of 0.3 was assumed as an upper limit of contamination from conveyer to the surface of a previously uncontaminated chicken piece. The model showed that the highest concentration of gliadin on the second product would be 6.3 ppm which is below the legislated limit of low-gluten. Information of direct commercial interest to Tegel has been extracted from all these results, and suggestions for future research have been made.

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