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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.
11

Kontaktna senzibilizacija kod obolelih od hronične venske insuficijencije / Contact Sensitization in Patients with Chronic Venous Insufficiency

Vujanović Ljuba 07 November 2014 (has links)
<p>Pojava alergijskog kontatnog dermatitisa koji nastaje kao komplikacija tokom lečenja hronične venske insuficijencije je dobro poznata. Cilj istraživanja je bio da se kod obolelih od hronične venske insuficijencije utvrdi učestalost kontaktne senzibilizacije ekcemskog tipa, potom da li postoji rizik za nastanak kontaktne senzibilizacije kao i postojanje korelacije između dužine trajanja bolesti i kontaktne senzibilizacije. Hipoteza rada je da osobe sa hroničnom venskom insuficijencijom značajno če&scaron;će razvijaju kontaktnu senzibilizaciju nego osobe bez hronične venske insuficijencije, da imaju veći rizik za nastanak kontaktne senzibilizacije kao i da je učestalost kontaktne senzibilizacije u pozitivnoj korelaciji sa dužinom trajanja bolesti. Istraživanje je sprovedeno nad 266 ispitanika. Formirane su dve grupe. Eksperimentalnu grupu su činili oboleli od hronične venske insuficijencije upućeni na alergolo&scaron;ko testiranje pod sumnjom na postojanje kontaktnog dermatitisa, a kontrolnu grupu su činili bolesnici bez hronične venske insuficijencije epikutano testirani pod sumnjom na postojanje kontaktnog dermatitisa. Obolelima od hronične venske insuficijencije je procenjena težina bolesti na osnovu CEAP klasifikacije. Potom je svaki ispitanik podvrgnut alergolo&scaron;kom epikutanom testiranju pač testom. Istraživanje je pokazalo da je učestalost kontaktne senzibilizacije među obolelima od hronične venske insuficijencije iznosila 49,3%. Učestalost kontaktne senzibilizacije kod osoba sa hroničnom venskom insuficijencijom na alergene: iz sastava Evropske standardne baterije je iznosila 31,55%; baterije specifične za hroničnu vensku insuficijenciju je iznosila 28,45%; komercijalno dostupne baterije alergena ubikvitarnih korovskih biljaka iz porodice Compositae je iznosila 6,69%; originalno spravljene ekstrakte ubikvitarnih korovskih biljaka Vojvodine je iznosila 6,11%. Ne postoji statistički značajna razlika u odnosu na pol. Prevalencija kontaktne senzibilizacije kod osoba sa hroničnom venskom insuficijencijom se nije statistički značajno razlikovala od osoba koje nisu imale hroničnu vensku insuficijenciju. Pozitivnost epikutanog alergolo&scaron;kog testa kojim se potvrđuje postojanje kontaktne senzibilizacije je bila statistički značajno vi&scaron;a kod osoba sa hroničnom venskom insuficijencijom. Osobe sa hroničnom venskom insuficijencijom su imale 2,45 puta vi&scaron;i rizik za nastajanje kontaktne senzibilizacije na dva i vi&scaron;e alergena, a 3,69 puta vi&scaron;i rizik za nastajanje kontaktne senzibilizacije na pet i vi&scaron;e alergena u odnosu na one bez hronične venske insuficijencije. Učestalost kontaktne senzibilizacije je u pozitivnoj korelaciji sa dužinom trajanja bolesti.</p> / <p>Development of allergic contact dermatitis as a complication of treatment of chronic venous insufficiency is well known. The aim of this study was to determine the incidence of eczematous contact sensitization in patients with chronic venous insufficiency, possible risks for the development of contact sensitization, and the correlation between disease duration and contact sensitization. The working hypothesis was that the incidence of contact sensitivity is significantly higher in individuals with chronic venous insufficiency than in those without chronic venous insufficiency, that they are at greater risk of developing contact sensitization, and that there is a positive correlation between the incidence of contact sensitization and the disease duration. The study included 266 patients. They were divided into two groups: the study group included patients with chronic venous insufficiency referred for allergy testing due to suspected contact dermatitis, and the control group included patients without chronic venous insufficiency patch tested for suspected contact dermatitis. The severity of chronic venous insufficiency was assessed by CEAP classification. Thereafter, each patient underwent patch testing. The research has shown that the incidence of contact sensitization among patients with chronic venous insufficiency was 49.3%. In these patients, the incidence of contact sensitization to the European standard battery of allergens was 31.55%; to the battery specific for chronic venous insufficiency it was 28.45%; to commercially available batteries of allergens of ubiquitous plants from the Compositae family it was 6.69%; and to originally prepared extracts of ubiquitous plants found in Vojvodina it was 6.11%. There was no statistically significant difference in relation to sex. The prevalence of contact sensitization in patients with chronic venous insufficiency was not significantly different from those without chronic venous insufficiency. Positive patch test reaction rates, confirming the existence of contact sensitization, were significantly higher in patients with chronic venous insufficiency. Patients with chronic venous insufficiency had a 2.45-fold higher risk for developing contact sensitization to two or more allergens, and a 3.69-fold higher risk for developing contact sensitization to five or more allergens compared to those without chronic venous insufficiency. There was a positive correlation between the incidence of contact sensitization and the duration of the disease.</p>
12

Dermal cell trafficking : from microscopy to microdialysis /

Sjögren, Florence, January 2005 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2005. / Härtill 6 uppsatser.
13

Biophysical aspects of contact dermatitis and its prevention /

Kuzmina, Natalia, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol inst., 2004. / Härtill 5 uppsatser.
14

Effets des sensibilisants sur la synthèse de la prostaglandine E2 : Mécanismes et intérêt dans la prédiction de l’allergie de contact / Sensitizers'effects on prostaglandin E2 synthsis : mecanisms of action and potential to predict allergic contact dermatitis

Del Bufalo, Aurelia 20 January 2012 (has links)
Les sensibilisants de contact sont des molécules réactives électrophiles qui ont la capacité de modifier des protéines de la peau pour former un antigène. Au delà de ce mécanisme d'hapténisation, le signal de danger induit par les sensibilisants conduisant à l'activation des cellules dendritiques (DC) est un élément déterminant dans l'induction de cellules T spécifiques de l'haptène. Dans le contexte du 7ième amendement à la directive cosmétique européenne, la mise en place d'une batterie de tests in vitro permettant de prédire le potentiel sensibilisant de molécules est indispensable pour l'industrie cosmétique. Tandis que la plupart des études in vitro étudient les signaux de danger induits par les sensibilisants dans des modèles homéostasiques, nous nous sommes intéressés à l'effet des sensibilisants sur la mise en place d'une réponse inflammatoire. Lorsque la lignée U937 est différenciée avec du PMA et stimulée avec du LPS, les facteurs de transcription NF-κB et Nrf2 sont activés et l'acide arachidonique (AA) est métabolisé au travers de la cascade cPLA2 / COX-2. L'ensemble de ces voies activées conduit à la production par les U937 d'un grand nombre de médiateurs inflammatoires (IL-1β, TNF-α, IL-6, IL-10, IL-8, PGE2, PGD2, TxB2). Dans ce modèle, nous avons analysé l'effet de 6 sensibilisants de potentiels variés (DNCB, PPD, HQ, PG, CIN, EUG) et montré que de façon inattendue, tous les sensibilisants étudiés diminuent significativement et de façon spécifique la production de tous les prostanoïdes et en particulier de PGE2 induite par PMA/LPS. Nous avons de plus démontré que selon les sensibilisants, les cibles de cette inhibition au sein de la cascade métabolique de l'AA diffèrent, même si elles se focalisent la plupart du temps (sauf pour le DNCB) sur l'enzyme COX-2 (inhibition de son expression et/ou de son activité). Pour le DNCB, le mécanisme d'inhibition semble plutôt impliquer sa capacité à réagir fortement avec les groupements résidus thiols, ce qui se traduit en particulier par la déplétion du GSH intracellulaire et engendrerait l'inhibition des synthases dépendantes du GSH pour leurs activités. En parallèle de cette étude mécanistique, nous avons appréhendé la problématique du point de vue statistique et vérifié sur un set plus important et diversifié de molécules (160 molécules) que le paramètre « inhibition de PGE2 » pouvait être un bon test de prédiction de l'HSRC. L'étude statistique a permis de déterminer le modèle prédictif du test PGE2 et de mettre en évidence de bonnes performances (78%) par rapport aux prédictions du LLNA. Au-delà, une certaine complémentarité du test PGE2 avec d'autres tests in vitro (MUSST, Nrf2-HTS) a pu être mise en évidence. En conclusion, au travers de cette étude, nous avons pu mettre en évidence de nouvelles propriétés biochimiques des sensibilisants. Même si la signification biologique de la diminution de PGE2 par les sensibilisants de contact demeure complexe d'interprétation, ce paramètre a permis le développement d'un test qui prédit avec de bonnes performances le caractère sensibilisant de molécules et dont la position au sein d'une batterie prédictive d'évaluation de l'allergie de contact reste à être précisée. / Contact sensitizers are defined as reactive molecules (electrophilic) which have the ability to modify skin proteins to form an antigen (hapten). In addition to the haptenation mechanism, danger signals, leading to the activation of dendritic cells, are described to be crucial for the effective induction of an hapten-specific T cell immune response. In the context of the 7th amendment to the Cosmetic Directive, the cosmetic industry is concerned by the challenge of finding non-animal approaches to assess the sensitizing potential of chemicals. While danger signals induced by sensitizers in steady-state conditions have already been analyzed, we chose to investigate the impact of sensitizers on the course of an inflammatory response. For this purpose we used the U937 cell line differentiated with PMA and activated with LPS. In these conditions, cells produce a large amount of inflammatory mediators (IL-β, TNF-α, IL-6, IL-10, IL-8, PGE2, PGD2, TxB2) through the activation of pathways leading to the activation of the transcription factors NF-κB and Nrf2 and through AA metabolism by the cPLA2/COX-2 cascade. Interestingly, we showed that 6 contact sensitizers with various potential (DNCB, PPD, HQ, PG, CIN, EUG) significally and specifically decrease the production of prostanoïds and in particular of PGE2 induced by PMA/LPS. We further demonstrated that there is no unique inhibition profile of the sensitizers even if the majority (except for DNCB) of the effects applies on COX-2 (i.e. inhibition of the expression and/or activity). For DNCB, inhibition mechanism appears to be dependant of its capacity to react with thiols residues and in particular to deplete intracellular glutathione possibly leading to the inactivation of the PG-synthases. In parallel, we assess a statistical analysis on 160 molecules that allow us to define the test parameters (a molecule is a sensitizer if the PGE2 inhibition at 24h is more than 60%) and to calculate the test performance toward LLNA (78%). Moreover we demonstrated that the PGE2 test could be complementary to other already existing in vitro tests like MUSST or Nrf2-HTS. In summary, we add here a new insight into the multiple biochemical effects described so far for sensitizers. Even if the underlying biological relevance remains unclear, the parameter “PGE2 inhibition” is good test for skin sensitization evaluation. Further studies will precise how this parameter could be implemented into an alternative testing strategy for the evaluation of skin sensitization.
15

Stanovení alergenních a potenciálně alergenních kovů v kosmetických přípravcích / Determination of alergenic and potential alergenic metals in cosmetics

Krakovková, Lenka January 2010 (has links)
The aim of the diploma thesis was to provide an overview of the prevalence of allergenic and potentially allergenic metals in eye shadows. The diploma thesis gives an overview of the legislation on cosmetics and description of the types of allergenic reactions caused by allergenic and potential allergenic metals in eye shadows. Listed below are the preparation methods of the samples for analysis and the list of the methods by which can the selected metals be analyzed. The experimental part of the diploma thesis deals with an analysis of selected allergenic and potentially allergenic metals in eye shadows. In the experimental part of diploma thesis method of sample preparation for analysis of eye shadows and a method of analysis of sample of eye shadows by ICP-MS have been optimized. Monitored analytes were selected metals. Altogether 6 samples of eye shadows from different manufacturers were chosen. Measured results have been statistically processed, confronted with the applicable legislation and assessed in terms of possible allergic reactions.
16

In-vivo-konfokale Laserscanmikroskopie: Diagnostische Kriterien für die Differenzierung vesikulöser/ bullöser Dermatosen / Morphologic criteria of vesiculobullous skin disorders by in vivo reflectance confocal microscopy

Samhaber, Kinga 16 November 2016 (has links)
No description available.
17

Avaliação da dermatite de contato alérgica ao níquel através da técnica de  imuno-histoquímica / Evaluation of nickel allergic contact dermatitis using the immunohistochemical technique

Silvestre, Marilene Chaves 22 May 2017 (has links)
A dermatite de contato alérgica (DCA) ao íon níquel (Ni2+) é uma dermatose inflamatória frequente nos países industrializados. Envolve a ativação de células T específicas ao Ni2+, seguida da proliferação e indução de um perfil misto de citocinas, tanto pró-inflamatórias quanto reguladoras, sugerindo que vários subtipos de células T (helper - Th e citotóxica - Tc) estão envolvidos na resposta imune. Este estudo teve como objetivo a análise das citocinas TNF-alfa, INF-y, IL-2, IL-4, IL-10, IL-13, IL-17 e IL-23 pela técnica de imuno-histoquímica, para tentar identificar a prevalência de um ou mais subtipos de células T (Th/Tc), nos eczemas crônico e agudo de pacientes com DCA ao Ni2+. Avaliamos 20 pacientes (17 mulheres e 3 homens, com idade mediana de 46 anos) apresentando eczema crônico, pelo contato cotidiano do paciente com o Ni2+. Foram coletadas duas biópsias de pele em cada um dos 20 pacientes, a primeira no local do eczema crônico ao Ni2+, antes da aplicação do teste de contato (TC); e a segunda no local do eczema agudo, provocado pelo TC com o sulfato de níquel, 48 horas após sua fixação, nas leituras positivo forte (++) ou positivo muito forte (+++). Foram 160 amostras de eczema agudo e 160 de eczema crônico, perfazendo um total de 320 amostras. Apenas três amostras foram excluídas devido a algum tipo de falha técnica, como, por exemplo, o descolamento dos cortes de pele da lâmina. Para a análise dos dados utilizou-se o software estatístico STATA versão 13. As amostras coradas revelaram resultados positivos para as oito citocinas estudadas, e estas apresentaram valores heterogêneos. Esta heterogeneidade foi medida pelo coeficiente de variação, indicando a variabilidade do conjunto dos dados obtidos. O TNF-alfa, IFN-y, IL-4, IL-13 e IL-17 tiveram prevalência maior no eczema crônico do que no eczema agudo, a IL-2 e IL-23 apresentaram maior prevalência no eczema agudo, em comparação com o eczema crônico e a IL-10 apresentou prevalência similar tanto no eczema agudo quanto no crônico, porém, estas prevalências foram muito baixas, em ambos os eczemas. O TNF-alfa foi a citocina que mais prevaleceu no eczema crônico e a IL-2 foi a mais prevalente no eczema agudo. Porém, estas prevalências foram estatisticamente significantes apenas para a IL-4 e IL-13. Verificamos, nos eczemas crônico e agudo, a presença de um perfil misto de citocinas dos subtipos de células T (Th/Tc), sugerindo que as respostas imunes são expressas ao mesmo tempo. Entretanto, são necessários mais estudos para uma compreensão mais ampla sobre o perfil das citocinas na DCA ao Ni2+, o que poderia levar a novas abordagens terapêuticas / Allergic contact dermatitis (ACD) to nickel (Ni+2) is a inflammatory dermatosis, common in industrialized countries. It involves the activation of nickel-specific T cells, followed by the proliferation and induction of a mixed profile of both proinflammatory and regulatory cytokines, suggesting that several T cell subtypes (helper - Th and cytotoxic - Tc) are involved in the immune response. This study aimed to analyze the cytokines TNF-alfa, INF-y, IL-2, IL-4, IL-10, IL-13, IL-17 and IL-23 using the immunohistochemistry technique in order to try to identify the prevalence of one or more T cell subtypes (Th/Tc) in the chronic and acute eczema of patients with ACD to Ni+2. We evaluated 20 patients (17 women and 3 men, median age of 46 years) with chronic eczema, by the patient\'s daily contact with Ni+2. Two skin biopsies were collected in each of the 20 patients, the first at the site of the chronic eczema to Ni+2, prior to the application of the contact test (CT); and the second at the site of acute eczema caused by CT with nickel sulphate, 48 hours after its fixation in the strong positive (++) or very strong positive (+++) readings. There were 160 samples of acute eczema and 160 of chronic eczema, a total of 320 samples. Only three samples were excluded due to some kind of technical failure, such as detachment of the skin cuts from the microscope slide. Statistical software STATA version 13 was used to analyze the data. The stained samples showed positive results for the eight cytokines studied, and these presented heterogeneous values. This heterogeneity was measured by the coefficient of variation, indicating the variability of the data set obtained. TNF-alfa, IFN-y, IL-4, IL-13 and IL-17 had a higher prevalence in chronic eczema than in acute eczema, IL-2 and IL-23 were more prevalent in acute eczema compared to chronic eczema and IL-10 presented similar prevalence in both acute and chronic eczema, however, a very low prevalence in both eczema. TNF-alfa was the most prevalent cytokine in chronic eczema and IL-2 was the most prevalent in acute eczema. However, these prevalences were statistically significant only for IL-4 and IL-13. In chronic and acute eczema, we observed the presence of a mixed cytokine profile of the T cell subtypes (Th/Tc), suggesting that immune responses are expressed at the same time. However, further studies are needed for a broader understanding of the cytokine profile in ACD to Ni+2, which could lead to new therapeutic approaches
18

Avaliação da dermatite de contato alérgica ao níquel através da técnica de  imuno-histoquímica / Evaluation of nickel allergic contact dermatitis using the immunohistochemical technique

Marilene Chaves Silvestre 22 May 2017 (has links)
A dermatite de contato alérgica (DCA) ao íon níquel (Ni2+) é uma dermatose inflamatória frequente nos países industrializados. Envolve a ativação de células T específicas ao Ni2+, seguida da proliferação e indução de um perfil misto de citocinas, tanto pró-inflamatórias quanto reguladoras, sugerindo que vários subtipos de células T (helper - Th e citotóxica - Tc) estão envolvidos na resposta imune. Este estudo teve como objetivo a análise das citocinas TNF-alfa, INF-y, IL-2, IL-4, IL-10, IL-13, IL-17 e IL-23 pela técnica de imuno-histoquímica, para tentar identificar a prevalência de um ou mais subtipos de células T (Th/Tc), nos eczemas crônico e agudo de pacientes com DCA ao Ni2+. Avaliamos 20 pacientes (17 mulheres e 3 homens, com idade mediana de 46 anos) apresentando eczema crônico, pelo contato cotidiano do paciente com o Ni2+. Foram coletadas duas biópsias de pele em cada um dos 20 pacientes, a primeira no local do eczema crônico ao Ni2+, antes da aplicação do teste de contato (TC); e a segunda no local do eczema agudo, provocado pelo TC com o sulfato de níquel, 48 horas após sua fixação, nas leituras positivo forte (++) ou positivo muito forte (+++). Foram 160 amostras de eczema agudo e 160 de eczema crônico, perfazendo um total de 320 amostras. Apenas três amostras foram excluídas devido a algum tipo de falha técnica, como, por exemplo, o descolamento dos cortes de pele da lâmina. Para a análise dos dados utilizou-se o software estatístico STATA versão 13. As amostras coradas revelaram resultados positivos para as oito citocinas estudadas, e estas apresentaram valores heterogêneos. Esta heterogeneidade foi medida pelo coeficiente de variação, indicando a variabilidade do conjunto dos dados obtidos. O TNF-alfa, IFN-y, IL-4, IL-13 e IL-17 tiveram prevalência maior no eczema crônico do que no eczema agudo, a IL-2 e IL-23 apresentaram maior prevalência no eczema agudo, em comparação com o eczema crônico e a IL-10 apresentou prevalência similar tanto no eczema agudo quanto no crônico, porém, estas prevalências foram muito baixas, em ambos os eczemas. O TNF-alfa foi a citocina que mais prevaleceu no eczema crônico e a IL-2 foi a mais prevalente no eczema agudo. Porém, estas prevalências foram estatisticamente significantes apenas para a IL-4 e IL-13. Verificamos, nos eczemas crônico e agudo, a presença de um perfil misto de citocinas dos subtipos de células T (Th/Tc), sugerindo que as respostas imunes são expressas ao mesmo tempo. Entretanto, são necessários mais estudos para uma compreensão mais ampla sobre o perfil das citocinas na DCA ao Ni2+, o que poderia levar a novas abordagens terapêuticas / Allergic contact dermatitis (ACD) to nickel (Ni+2) is a inflammatory dermatosis, common in industrialized countries. It involves the activation of nickel-specific T cells, followed by the proliferation and induction of a mixed profile of both proinflammatory and regulatory cytokines, suggesting that several T cell subtypes (helper - Th and cytotoxic - Tc) are involved in the immune response. This study aimed to analyze the cytokines TNF-alfa, INF-y, IL-2, IL-4, IL-10, IL-13, IL-17 and IL-23 using the immunohistochemistry technique in order to try to identify the prevalence of one or more T cell subtypes (Th/Tc) in the chronic and acute eczema of patients with ACD to Ni+2. We evaluated 20 patients (17 women and 3 men, median age of 46 years) with chronic eczema, by the patient\'s daily contact with Ni+2. Two skin biopsies were collected in each of the 20 patients, the first at the site of the chronic eczema to Ni+2, prior to the application of the contact test (CT); and the second at the site of acute eczema caused by CT with nickel sulphate, 48 hours after its fixation in the strong positive (++) or very strong positive (+++) readings. There were 160 samples of acute eczema and 160 of chronic eczema, a total of 320 samples. Only three samples were excluded due to some kind of technical failure, such as detachment of the skin cuts from the microscope slide. Statistical software STATA version 13 was used to analyze the data. The stained samples showed positive results for the eight cytokines studied, and these presented heterogeneous values. This heterogeneity was measured by the coefficient of variation, indicating the variability of the data set obtained. TNF-alfa, IFN-y, IL-4, IL-13 and IL-17 had a higher prevalence in chronic eczema than in acute eczema, IL-2 and IL-23 were more prevalent in acute eczema compared to chronic eczema and IL-10 presented similar prevalence in both acute and chronic eczema, however, a very low prevalence in both eczema. TNF-alfa was the most prevalent cytokine in chronic eczema and IL-2 was the most prevalent in acute eczema. However, these prevalences were statistically significant only for IL-4 and IL-13. In chronic and acute eczema, we observed the presence of a mixed cytokine profile of the T cell subtypes (Th/Tc), suggesting that immune responses are expressed at the same time. However, further studies are needed for a broader understanding of the cytokine profile in ACD to Ni+2, which could lead to new therapeutic approaches
19

Alternative mechanisms in skin allergy processes : contribution of radical reactions from the molecule to the tissue / Implication des mécanismes de type radicalaire dans les processus de sensibilisation cutanée : compréhension en allant de la molécule au tissu

Kuresepi, Salen 11 May 2018 (has links)
L’allergie de contact est une pathologie touchant de 15 à 20 % de la population occidentale. A l’heure actuelle il n’existe aucun traitement, la seule façon efficace de prévention étant l’éviction totale des allergènes. Les tests de sensibilisation de nouvelles molécules avant leur mise sur le marché ont été réalisés sur l’animal jusqu’à l’interdiction dans le 7ème amendement à la directive Européenne concernant l’industrie cosmétique. Dans ce contexte il est primordial de développer des méthodes alternatives. Ce travail de thèse propose d’analyser la problématique de l’allergie de contact en allant de la molécule au tissu pour les allergènes réagissant par voie radicalaire :In chemico : étude de la réactivité des hydroperoxydes allyliques vis-à-vis des acides aminés par la RMNIn situ : études de radicaux issus de ces composés sur des épidermes humains reconstitués par RPEIn cellulo : étude du stress oxydant sur les cellules dendritiques et la voie de signalisation Keap1/Nrf2/ARE. / Allergic contact dermatitis is a pathology affecting 15 to 20% of the Western population. Until now no treatment exists, the prevention is the eviction of allergens. In the past, tests concerning new molecules for the market were tested on animals until the prohibition in the 7th amendment of the European directive concerning the cosmetics industry. In this context it is essential to develop alternative methods to assess the allergenic potential of chemicals.This manuscript proposes to analyze the problem of the allergic contact dermatitis from the molecule to the tissue for allergens reacting through radical mechanisms:In chemico: study of the reactivity profile of allylic hydroperoxides toward amino acids by NMRIn situ: radical intermediates formation on reconstructed human epidermis from allylic hydroperoxides by EPR In cellulo: study of the oxidative stress from allylic hydroperoxides on dendritic cells trough the Keap1/Nrf2/ARE sensor pathway.
20

Uticaj pola, težine i dužine trajanja oboljenja na kontaktnu senzibilizaciju kod obolelih od vulgarne psorijaze / The influence of sex, severity and duration of disease on contact sensitization in patients with psoriasis vulgaris

Petrović Aleksandra 05 February 2015 (has links)
<p>Kontaktna senzibilizacija, kao stanje specifične reaktivnosti kože, može biti egzogeni pokretač psorijaze. Rezultat je interakcije endogenih i egzogenih činioca. Jedan od najznačajnijih endogenih faktora kome se pripisuje uloga faktora rizika jeste pol. Cilj istraživanja bio je da se kod obolelih od psorijaze utvrdi učestalost i distribucija kontaktne senzibilizacije u odnosu na pol, razlike u distribuciji kontaktne senzibilizacije po polu&nbsp; između osoba obolelih od psorijaze i osoba pod sumnjom na postojanje kontaktnog alergijskog dermatitisa, povezanost kontaktne senzibilizacije i težine kliničkog nalaza i povezanost kontaktne senzibilizacije i dužine trajanja oboljenja. Hipoteza istraživanja polazila je od pretpostavke da je kontaktni alergijski dermatitis redak kod obolelih od psorijaze, jer hronična inflamacija u koži smanjuje njenu sposobnost specifične senzibilizacije a da je veća učestalost kontaktne senzibilizacije kod osoba ženskog pola rezultat egzogenog faktora tj.ekspozicije, kao i da je učestalost kontaktne senzibilizacije u pozitivnoj korelaciji sa težinom i dužinom trajanja oboljenja. Istaživanje je sprovedeno kod 176 ispitanika koji su bili podeljeni u dve grupe. Eksperimentalnu grupu su činili oboleli od psorijaze, a kontrolnu grupu ispitanici upućeni na alergolo&scaron;ko testiranje pod sumnjom na postojanje kontaktnog alergijskog dermatitisa. Obolelima od psorijaze je ocenjivana težine oboljenja PASI skorom, a svi ispitanici bili su alergolo&scaron;ki testirani epikutanim -pač testom. Pozitivni rezultati alergolo&scaron;kog testiranja su analizirani, u cilju utvrđivanja kliničke relevantnosti istih. Ispitanicima u grupi obolelih od psorijaze je testom skarifikacije određivano prisustvo ili odsustvo Koebnerovog izomorfnog podražajnog fenomena. Istraživanjem je utvrđeno, da se kontaktno reagovanje kod obolelih od psorijaze na najmanje jedan standardni alergen nije statistički značajno razlikovalo od reagovanja osoba kod kojih je postavljena sumnja na postojanje kontaktnog alergijskog dermatitisa, ali je senzitivnost izražena kroz prosečan broj pozitivnih testova po jednom ispitaniku bila statistički značajno niža kod obolelih od psorijaze. Poređenjem kontaktnog reagovanja mu&scaron;karaca i žena nisu utvrđene značajna razlike u reagovanju u odnosu na pol. Težina oboljenja nije uticala na učestalost kontaktne senzibilizacije kod obolelih od psorijaze, ali je učestalost kontaktne senzibilizacije bila u pozitivnoj korelaciji sa dužinom trajanja bolesti. Niža stopa kontaktnog reagovanja utvrđena je kod osoba obolelih od psorijaze koji su imali pozitivan Koebnerov fenomen u trenutku ispitivanja.</p> / <p>Contact sensitization as a state of specific skin reactivity may provoke psoriasis resulting from an interaction between extrinsic and intrinsic factors. One of the most significant factors characterized, as a risk factor, is the sex. The aim of this study was to determinate the frequency and distribution of contact sensitization in patients with&nbsp; psoriasis with respect to their sex, as well as the differences in the distribution of contact sensitization in both sexes, namely&nbsp; with patients with psoriasis and patients&nbsp; suspected to allergic contact dermatitis. Consequently, appropriate attention was paid to the correlation between contact sensitization and disease severity, and between contact sensitization and disease duration. Hypothesis were based on the assumption that allergic contact dermatitis is rare in&nbsp; patients with psoriasis, as a chronic inflammation of the skin reduces its ability specific sensitization, as well as that the higher frequency of contact sensitization in females represent a result of exogenous factors, i.e. exposition, and finally that there is a positive correlation between the incidence of contact sensitization and the disease severity, and contact sensitization and the disease duration. The study included 176 patients. They were divided into two groups: the study group included patients with psoriasis, while the control group included patients referred for allergy testing, since they were suspected to allergic contact dermatitis. The severity of psoriasis was evaluated by PASI score. Thereafter,&nbsp; each patient underwent patch testing. The positive results of patch tests were evaluated with the aim to define their clinical relevancy. Subjects from the group of psoriatic patients passed scarification test carried out to indicate the presence or absence of K&ouml;ebner isomorphic phenomenon. This research led us to the conclusion that the positive reaction of psoriatic patients to at least one standard allergen did not indicate a statistically significant different reaction when compared to the reaction of patients suspected to allergic contact dermatitis. From the other side, the sensitivity expressed through the average number of positive&nbsp; tests per one&nbsp; tested&nbsp; patients was&nbsp; significantly lower in&nbsp; patients&nbsp; with psoriasis. Comparison of the contact response of men and women showed no significant differences in response with respect to&nbsp; their sex. The&nbsp; disease severity did not influence the frequency of contact sensitization in patients&nbsp; with&nbsp; psoriasis. At&nbsp; the same time, the frequency of contact sensitization stood in a positive correlation with the duration of disease. The lower rate of contact sensitization was found in patients with psoriasis who have had a&nbsp; positive K&ouml;ebner phenomenon at&nbsp; the time of testing.</p>

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