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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.
91

Identificação, expressão, purificação e caracterização de novos alérgenos do veneno da vespa  Polybia paulista / Identification, expression, purification and characterization of new allergens from the Polybia paulista wasp venom

Karine De Amicis Lima 14 September 2017 (has links)
As hipersensibilidades do tipo I são caracterizadas por um grupo heterogêneo de manifestações clínicas que atingem mais de 30% da população mundial. Novas reatividades a alérgenos regionais brasileiros têm sido descritas e muitas fontes ainda não são totalmente conhecidas. Dentre os alérgenos mais prevalentes estão os venenos de insetos. A vespa regional Polybia paulista (Hymenoptera vespidae) é endêmica no sudeste do Brasil e é responsável por acidentes graves, causando reações alérgicas que podem levar ao choque anafilático. Alguns componentes dos venenos de vespas de diferentes espécies apresentam mimetismo molecular ou biológico, podendo gerar reação imunológica cruzada, mas muitas vezes não são os responsáveis pelo desencadeamento da resposta alérgica. Isto ocasiona falha no diagnóstico e consequentemente no tratamento indicado, a imunoterapia alérgeno-específica. Diante desses fatos e do grande número de pacientes que procuram o Serviço de Imunologia Clínica e Alergia do Hospital das Clínicas de São Paulo (HCFMUSP) com manifestações clínicas de alergias a ferroadas de insetos, foi desenvolvida uma sistemática de investigação clínica e laboratorial, com ênfase na abordagem proteômica, para identificar e caracterizar físico-química e imunologicamente novos alérgenos do veneno da vespa Polybia paulista e estudar potenciais reatividades cruzadas com alérgenos já conhecidos. Vinte e um pacientes com história de anafilaxia a venenos de vespa foram selecionados para participar do estudo. Foram realizados testes cutâneos e in vitro com veneno de Polistes spp. disponível comercialmente e com o veneno da Polybia paulista, produzido seguindo o protocolo padronizado anteriormente. Os resultados mostraram que a maioria dos pacientes apresentam IgE específica para os dois venenos com maior reatividade ao veneno de Polybia e que o padrão de proteínas reconhecidas entre os dois venenos é diferente, evidenciando a necessidade de veneno de Polybia paulista na prática clínica nas regiões cuja vespa está presente. Foram identificadas mais de 2000 proteínas no extrato total do veneno de Polybia paulista e algumas proteínas alergênicas ainda não descritas. Dentre elas foi identificada uma nova isoforma ao antígeno 5 da vespa Polybia scutellaris relatada como hipoalergênica. A molécula foi produzida na forma recombinante com conformação adequada, pela primeira vez em E. coli. O alérgeno, registrado na IUIS como Poly p 5, foi reconhecido por IgEs no soro dos pacientes testados e apresenta reatividade cruzada com outros antígenos 5 homólogos. Testes de desgranulação de basófilos em linhagem celular de ratos mostraram que o Poly p 5 induziu pouca desgranulação, indicando seu potencial hipoalergênico / Type I hypersensitivity is characterized by heterogeneous clinical manifestations and specialists estimate that today around 30% of the general population suffers from an allergic disease. New allergens are being reported and some sources are not yet identified. Insect venoms are amongst the most prevalent allergen sources. The social wasp Polybia paulista (Hymenoptera vespidae) is endemic in the southeastern of Brazil and is responsible for serious accidents due to their venomous stings, causing allergic reactions that can lead to anaphylactic shock. Several components presenting molecular or biological mimicry can be found in different species of wasps and lead to a cross-immunological reaction but they are not always responsible for the allergic manifestations. Therefore, diagnostic and consequently immunotherapy is unsuccessful, since specific allergen identification is crucial. Considering the high number of patients attended at the \"Serviço de Imunologia Clínica e Alergia do Hospital das Clínicas de São Paulo\" with clinical manifestations of allergies not yet determined or barely studied, an approach involving a systematic clinical, laboratorial and investigative practice through a proteomic analysis was created to identify and characterize new allergens of Polybia paulista venom. Twenty-one patients with clinical history of anaphylaxis to Hymenoptera venoms were selected for this work. Cutaneous and in vitro tests were performed using Polistes venom commercially available as well as Polybia paulista venom, produced following a published protocol. The results shows that the majority of the patients has specific IgE for both venoms with biggest reactivity to Polybia paulista venom and the protein profile recognized in these venoms is different. More than 2000 proteins were identified in the whole venom extract of Polybia paulista and some of the allergenic proteins are not yet described in this venom. Among them, a new isoform that is similar to antigen 5 from Polybia scutellaris, already known as hypoallergenic. The molecule was produced as a recombinant properly folded for the first time in E. coli. The allergen, registered at IUIS as Poly p 5, was recognized by IgEs in the sera of 50% of the patients tested and has cross-reactivity with other homologs of antigen 5. Basophil degranulation tests in rat lineage cells showed that Poly p 5 induced little degranulation, indicating the hypoallergenic potential of this molecule
92

Mecanismos regulatórios mediados pelos anticorpos maternos na modulação da resposta de hipersensibilidade do tipo I ao alérgeno ovalbumina em camundongos neonatos. / Regulatory mechanisms involved on the offspring type I hypersensitivity response inhibition mediated by maternal immunixation with OVA.

Jefferson Russo Victor 05 December 2008 (has links)
Avaliamos os mecanismos regulatórios desencadeados pela imunização materna na resposta alérgica da prole OVA. A imunização materna com OVA promoveu alterações como o aumento da expressão dos receptores FcgRIIb nos linfócitos B esplênicos dos neonatos aos 3 dias de idade (d.i.), o que se manteve até os 20 d.i. Com a imunização das proles no período neonatal a imunização materna inibiu a produção de anticorpos IgE anti-OVA. Além disso, foi observado na população de linfócitos B da prole o aumento da expressão dos receptores FcgRIIb e CD44. A transferência passiva de IgG de mães imunes no pós-natal mostrou uma inibição da produção de IgE, e no período pré-natal foi capaz de reduzir a expressão das moléculas CD40 e CD23 nos linfócitos B e a secreção de IL-10 em linfócitos T CD4 na prole no período neonatal. As evidências mostram que a imunização pré-concepcional com OVA induz mecanismos que regulam a resposta IgE da prole imunizada no período neonatal, o que foi parcialmente observado com a transferência passiva de anticorpos IgG durante o período pré e pós-natal. / To evaluate the regulatory mechanisms triggered by maternal immunization in the immune response of the offspring, the effect of preconceptional immunization with OVA was evaluated. Maternal immunization with OVA led to early alteration with increased expression of FcgRIIb in B lymphocytes from 3 days old pups. Offspring from immune mother showed diminished percentage of CD4 T cells IL-4+. The immunization of offspring during neonatal period showed that maternal immunization inhibits the production of anti-OVA IgE antibodies. The evaluation of CD4 T cell population revealed diminished IL-4+ cells. Passive IgG transfer from immune mother during neonatal period showed inhibition in the IgE synthesis, during pregnancy showed capacity to reduce the expression of CD40 molecules in B cells from neonatal pups. These evidences show that maternal OVA immunization down regulates the IgE response of offspring including phenotypic and functional alteration in B and CD4 T cells. These alterations were partially observed with IgG transfer during pregnancy or after birth.
93

Padronização de modelo de inflamação alérgica pela exposição a picadas de mosquitos Aedes aegypti. / Standardization of a model of allergic inflammation by exposure to Aedes aegypti mosquito bites.

Michele Silva de Barros 18 September 2012 (has links)
Durante o repasto sanguíneo, fêmeas do mosquito Aedes aegypti inoculam saliva na pele de seu hospedeiro vertebrado, modulando suas funções imunológicas e facilitando a transmissão de doenças. Alguns componentes presentes na saliva de Ae. aegypti já foram descritos e caracterizados como alérgenos. No presente estudo, desenvolvemos um modelo de inflamação alérgica em camundongos expostos naturalmente às picadas de mosquitos Ae. aegypti. Nossos dados revelam que a sensibilização e posterior desafio com componentes salivares desse mosquito induz inflamação pulmonar com aumento no número de eosinófilos, células T CD4+, CD19+ e citocinas IL-4 e IL5 no lavado broncoalveolar, produção de muco e colágeno no pulmão, anticorpos IgE total e IgG1 e IgG2a específicos no soro, porém, sem alterações no padrão respiratório e reatividade das vias aéreas. Em conjunto, os resultados gerados neste trabalho confirmam o desenvolvimento de uma resposta alérgica diferente dos modelos clássicos dessa área com a presença de elementos que sugerem tanto um perfil Th1 quanto Th2 de resposta. / During blood feeding, Aedes aegypti female mosquitoes inoculate saliva into the skin of their vertebrate hosts, modulating their immune functions and facilitating disease transmission. Some components presents in the saliva of Ae. aegypti have been described and characterized as allergens. In this study, we developed a model of allergic inflammation in mice naturally exposed to Ae. aegypti mosquito bites. Our data show that the sensitization and subsequent challenged with this mosquito salivary components induces lung inflammation with increased numbers of eosinophils, T CD4+ and CD19+ cells and IL-4 and IL-5 in bronchoalveolar lavage, mucus and collagen production in lung, total IgE and specific IgG1 and IgG2a antibodies in serum, but no changes in breathing pattern and in the airways reactivity. Together, the results generated in the present study confirm the development of an allergic response that is different from classic models of this area with the presence of components which suggest both Th1 and Th2 responses.
94

Immunochemical Studies On The Major Cross-Reacting Allergens From The Pollen Of Parthenium Hysterophorous

Gupta, Neetu January 1995 (has links) (PDF)
No description available.
95

Fenomén non-compliance u pacientů s diagnózou alergie / The Non-Compliance Phenomenon by patients with allergy diagnosis

Hronková, Eva January 2008 (has links)
Diploma thesis deal with the non-compliance questions by allergic patients. The thesis describe in detail the alergic disease with focusing on the forms, levels, risk factors and impact of non-compliance phenomenon. The practical part use the obtained informations from the quantitative research. These data were processed and used for reach the goals of the thesis. The data analysis evaluates and confirms eventually deny the theoretical supposition.
96

Occupational exposure and ill-health among workers during latex glove manufacturing in Thailand

Sanguanchaiyakrit, Nuthchyawach January 2013 (has links)
Exposure to dust and latex allergens has been well established as a cause of health problems but there have been few studies that have examined the extent of problems in latex glove manufactures, especially in Thailand. Therefore, the overall aim of the study was to determine whether exposure to dust and latex allergens was associated with health problems in Thai latex glove manufacturing workers.The study was conducted in 3 latex glove factories in southern Thailand that employed 1,481 workers (931 Thai and 550 foreign workers). Full shift personal air sampling of workers in 10 different departments was carried out using the IOM Multidust™ sampling Head equipped with 25 mm 1.0 mm Polytetrafluoroethyene filters at a flow rate of 2 L/min. A commercial ELISA kit was employed to quantify levels of the Hev b 6.02 latex allergen in air sample extracts. Information on demographics and, occupational history, exposures and health related problems attributed to work was collected by questionnaires completed by Thai workers. Lung function testing using a spirometer was also conducted among Thai workers. Univariate linear mixed-model analysis was used to determine differences in the dust and specific latex allergen concentrations between factories, departments, shifts and days. Multivariate linear mixed model analysis was used to determine exposure determinants to estimate exposure concentrations of inhalable dust and specific latex allergen. Logistic regression analysis was used to determine association between exposure to inhalable dust and specific latex allergens.292 air samples were collected. The geometric mean (GM) and a range of inhalable dust was 0.88 (0.01 – 12.34) mg/m3. The highest dust levels were found in the Stripping 3.01, (0.73 – 12.34) mg/m3 and lowest in the Office 0.11, (0.06 – 0.92 mg/m3) departments. Hev b 6.02 levels were 9.35 (4.08 – 345.53) ng/m3 and the highest and lowest levels were also found in the Stripping [19.76, (4.72 – 192.90) ng/m3] and Office [5.60, (4.37 – 14.64) ng/m3] departments. Factory and Department were important determinants of both inhalable dust and Hev b 6.02levels. 660 (157 men, 503 women) out of 931 workers completed a self-reported questionnaire. The prevalence of health problems attributed to work was highest for skin problems (25.0%) followed by Rhinitis (23.9%), conjunctivitis (22.5%) and cough (16.2%). Cumulative exposure to dust was associated with conjunctivitis attributed to work (OR and 95%CI = 1.02, [1.00 - 1.03]) after adjusted for confounders. A negative association was found between rhinitis and exposure to average dust level (OR and 95%CI =0.69 [0.48 - 0.99]). No other associations were found between either exposure to dust and self-reported ill-health. There were also no association between exposure to Hev b 6.02 and ill-health although skin problems were associated with the highest Hev b 6.02 level (OR and 95% CI = 1.72 [1.02 - 2.91]). Lung function testing was conducted in 474 Thai workers; 41 had airway restriction, 3 airway obstruction and 1 with a combined problem. Cumulative exposure to dust was associated with airway restriction after adjustment for confounders (OR and 95% CI = 1.02 (1.00 - 1.04).
97

Analýza vybraných alergenů ve vonných kompozicích / Analysis of selected allergens in fragrances

Koláčková, Adéla January 2010 (has links)
This thesis is focused on potentially allergenic substances (PASs) in cosmetics. Their specific features, methods of control and observation are described. There are also mentioned dermatology problems connected with usage of perfumed cosmetic products in which the allergenic ingredients can be found and possibilities of their regulation. Fragrances are mixtures of natural or synthetic character which give the aroma. In nature, fragrances are produced mainly by plants. More than one hundred fragrances have been identified as allergens. Twenty six of them were declared as PASs. Allergenic components of perfume compositions are the main cause of allergic contact dermatitis. Experimental part of the thesis is focused on the procedure of analysis of specific allergenic fragrances (?-Amylcinnamaldehyde, Anisealcohol, Benzylsalicylate, Cinnamaldehyde, ?-Hexylcinnamaldehyde, 7-Hydroxycitronellal and Methyl-2-octynoate). Headspace-Solid Phase Microextraction connected with Gas Chromatography-Flame Ionisation Detector (HS-SPME-GC-FID) was used for extraction, analysis and identification of these substances. The method was validated and applied on the spectrum of real samples of cosmetic products.
98

Identifikace DNA rostlinných a živočišných druhů v potravinách použitím polymerázové řetězové reakce / Identification DNA of Plant and Animal Species in Food by Polymerase Chain Reaction

Šmíd, Jiří January 2015 (has links)
We were developing detection methods for three food allergens of plant origin. We used real-time PCR for soy detection in food oriented on gene lec, that is coding lektine specific for soy. On this target sequence were oriented PCR system with primers Le2F and Le2R and TaqMan probe Le2P. Detection limit (2,75 pg), practical detection limit (0,02 %), inclusivity and exclusivity were determined. Whole system were quantified. Real-time PCR for pistachio detection were based on primers and probe for gene COR. Detection limit (3,5 pg), practical detection limit (0,002 %), inclusivity and exclusivity were determined. For almond detection we were not succeed system, that fulfil all qualitative parametres.
99

Predictors of occupational sensitisation to grain dust allergens and changes in lung function among grain mill workers in Cape Town

Jeebhay, Mohamed Fareed 31 March 2017 (has links)
Occupationally-related airway diseases, including asthma and chronic obstructive lung disease, have emerged as having substantial public health importance. The aim of this study was to identify the predictors of occupational sensitisation to grain dust allergens and changes in lung function among grain mill workers in Cape Town. There were two major objectives of the study. Firstly, to determine which of the following factors determine the distribution of serum ECP (eosinophilic cationic protein): age, gender, grain dust exposure, smoking status, atopy and sensitisation to workplace allergens. Secondly, to investigate the risk factors associated with the following outcomes: i) sensitisation to occupational allergens; ii) diagnosis of occupational asthma; iii) diagnosis of chronic obstructive airways disease; and iv) longitudinal changes in lung function. The risk factors studied included age, gender, smoking habits, occupational exposure, lung function status on baseline survey (1989), and allergic sensitisation assessed at follow up (1996). The methods employed involved a repeat measures cross-sectional design including a cohort followed up at different points over a seven year period. Survey instruments included a questionnaire, spirometry and allergy tests (phadiotop, RAST for wheat, rye, Lepidoglyphus destructor, Tyrophagus putrescentiae and Sitophilus granarius). The results indicated an association of grain dust with pulmonary function and allergic sensitisation to grain dust constituents. After adjusting for known confounders such as age, gender and smoking, significant associations were found between employment duration and both decrements in lung function and sensitisation to wheat grain. A decrement of 278 ml in FEY 1 and 328 ml in FYC was associated with occupational sensitisation to wheat (and rye). Increasing employment duration resulted in annual decrements of 18.3 ml in FEY1 and 23 ml in FYC for every year employed. The odds for developing occupational asthma was only mildly elevated (OR=l.35) with increasing employment duration. Age, however, was found to be protective (OR=0.85). Although we were unable to demonstrate a relationship between across-week changes in lung function, at inception, and rapid longitudinal lung function decline, our findings suggested that longitudinal change was related to the degree of airway obstruction at inception. Sensitisation to grain dust allergens was also found to be an independent predictor for FEY 1 and FYC. The prevalence of sensitisation was the highest for wheat (26.4%), followed by Tyrophagus putrescentiae (22.6%), rye (21.7%), Lepidoglyphus destructor (15.1 %) and Sitophilus granarius (15.1 %). Sensitisation to wheat was highly correlated with sensitisation to rye (r = 0.92) and so were Lepidoglyphus destructor and Tyrophagus putrescentiae (r = 0.85). Although a large proportion of the workforce ( 41.5 % ) were sensitised to occupational allergens, the prevalence of respiratory symptoms was between 15.6% and 23.9%. There were 16.7% of workers with health outcomes which fulfilled our criteria for occupational asthma. Atopic workers in our study had at least a nine-fold increased odds of becoming sensitised to grain dust allergens (OR: 8.9-74.7) and a two-fold increased odds of developing occupational asthma (OR= 1.9-84.9). Furthermore, the study found that smokers had a twofold increased odds of becoming atopic, thereby placing them at greater risk of developing respiratory health problems. The mean ECP in this population was 15.4 ug/1 (SD:2.5). Although 45.3% of the workers were atopic, it was not found to be predictor of elevated ECP levels. We were however able to demonstrate a significant association between ECP and sensitisation to grain allergens. Workers sensitised to wheat (positive RAST) had, on average, 1. 78 ug/1 higher ECP levels. The odds of having an elevated ECP (> 15 ug/1) increased by 2.9 for workers sensitised to wheat grain. In conclusion, the results of the study indicate that selection effects are in operation, demonstrating the health worker effect. The findings also suggest that across week reactions may be less sensitive than the across shift changes in predicting rapid longitudinal decline in lung function. While we were able to characterise the distribution of ECP according to exposure, we were however unable to define the temporal relationship between elevated between exposures, ECP and lung function outcomes due to limitations of the study design.
100

Indoor Environmental Quality within an Elementary School Classroom: Measurements of <em>Felis domesticus</em> I, <em>Dermatophagoides pteronyssinus</em> I, <em>Dermatophagoides farinae</em> I, and <em>Blatella germanica</em> in Carpeting

Fowler, Jennifer 03 April 2009 (has links)
The United States Environmental Protection Agency acknowledges that indoor environments can impact the health of students and can affect concentration, attendance, and student performance (USEPA 2008). In a school year, children are required by the Florida Department of Education to be in school for a total of 180 days, which is 795 hours spent in a classroom (FLDOE 2008). In the elementary school setting, kindergarten classes typically spend a portion of the school day with floor-based activities. The American Lung Association (ALA) states that over 6.8 million children under the age of 18 are affected by asthma (ALA 2008). Allergic reactions and/or sensitization to allergens such as dust, animal dander, and cockroaches are among triggers associated with asthma cases. Literature suggests looking at the areas where individuals spend a considerable amount of time to identify potential exposure sources. Currently, many of these studies have been done regarding the home indoor environment; however, few specifically document the concentrations in carpeting in elementary schools and the exposure time associated with floor-based activities. The objective of this research was to quantify the concentrations of cat (Felis domesticus I), dust mite (Dermatophagoides pteronyssinus I, Dermatophagoides farinae I), and cockroach (Blatella germanica) allergens in carpeting in an elementary school kindergarten class and to document and quantify student group activities that are floor-based. One Florida elementary school classroom was identified as the study site. A total of eight reservoir dust samples were collected during the school year to be analyzed for Felis domesticus I, Dermatophagoides pteronyssinus I, Dermatophagoides farinae I, and Blatella germanica allergens. The sampling reservoir was the carpeting used for group floor-based activities by the school children. Dust samples from the carpet were analyzed by The Johns Hopkins University Reference Laboratory for Dermatology, Allergy, and Clinical Immunology (DACI). The sample collection methodology followed the "Dust Analysis Instructions for Use" provided by the DACI laboratory, along with the "nozzle sock" sampling media. Following discussions with the kindergarten teacher regarding curriculum and scheduled classroom activities, group floor activities were identified. The kindergarten class was observed periodically throughout a school year to document and quantify classroom activities that were floor-based. The information documented includes: occupancy of classroom, occupied floor area, occupant density, and time spent on carpeting. Felis domesticus I (Fel d I) measurements ranged from 2,206 - 10,558 ng of allergen/g of settled dust, Dermatophagoides pteronyssinus I (Der p I) measurements ranged from 3,408 - 86,704 ng/g and Dermatophagoides farinae I (Der f I) measurements ranged from 704 - 6,720 ng/g, and Blatella germanica (Bla g I) measurements were below detection limits. Based upon the DACI criteria, dust mite concentrations were moderate to high and cat concentrations were low to moderate. Kindergarten children spent approximately 38% of classroom time in floor-based activities.

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