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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.
161

Maximum voluntary bite force and hand grip strength in resistance-trained young adults : A pilot study

Hagen, Anton, Himmelroos, Anton January 2023 (has links)
Background  Maximum voluntary bite force (BF) and hand grip strength (HS) serve as muscle strength markers from the jaw motor system and hand motor system.   Aim  To investigate i) differences in maximum BF and HS between dominant and non-dominant sides, ii) differences between repeated tests in the same session and iii) correlation between BF and HS.     Methods Fifteen resistance trained adults (n=6 women, mean age 24 (SD 1.04) years and n=9 men, mean age 27 (SD 4.06) years) were tested with electronic BF and HS devices, with three repeated tests per side. Paired sample T-test was used to detect differences in BF and HS between sides and whether there was a difference between repeated tests. Pearson test was used to determine correlation between BF and HS. P-value <0.05 was considered statistically significant.    Results HS showed differences between dominant and non-dominant sides in three tests (T1 P=<0.0001, T2 P=0.0002 and T3 P=0.0011). BF showed differences between repeated tests in the same session for T1-T2 (P=0.007), T1-T3 (P<0.0001) and T2-T3 (P=0.028) on dominant side and between T1-T2 (P=0.014), T1-T3 (P=0.010) on non-dominant side. Correlation between BF and HS showed r=0.41 for merged data (dominant + non-dominant side) (P=0.02).   Conclusions  In the context of resistance trained adults, the findings showed that BF did not alter between sides while HS did, with higher force production for the dominant hand. Repeated tests showed differences between tests for BF, but not for HS. A weak to moderate correlation could be observed when comparing BF to HS.
162

Perceptions and Punishment of Human-Animal Altercations

Mata Guidi, Adriana C 01 January 2020 (has links)
Humans and animals have a widely varying relationship which has been studied at length. Examining our interactions with animals in negative contexts can help us further understand the factors that’s influence the nature of the human-animal relationship, particularly with our most popular companion animals. This study continues the use of a jury design, previously used in studies regarding animal abuse, to examine responses to a scenario of an altercation resulting in a dog biting a person. In this study, 243 undergraduate students read the scenario presented to them and completed a survey examining their judgements of blame and punishment for the incident. In the interest of examining the effects of different variables, participants were randomly presented with 1 of 18 potential scenarios in which the role of the human in potentially provoking the dog, the breed of the dog involved, and the degree of damage inflicted were manipulated. Results showed an avoidance toward making any judgements on the dog’s disposition, neither positively nor negatively. Additionally, some gender differences were discovered in responses related to euthanasia, blame on the owner, and the promotion of an obedience training program. Surprisingly, degree of damage did not have significant effects on responses, while dog breed differences revealed that participants placed greater blame and responsibility on owners of Pit bulls rather than the dog itself, which is potentially explained by the sample’s age demographics. The manipulation of human provocation of the incident proved to have the most significant effect of participant responses of blame and punishment, affecting perceptions of blame attributed to the dog and the victim, as well as the punishments and protections deemed appropriate. The results suggest an emphasis on human component in the perceptions of the human-animal relationship and provide insight on the variables relevant to the relationship.
163

Modeling and Control of an Automated Manual Transmission for EcoCAR 3 Vehicle

Modak, Aditya January 2017 (has links)
No description available.
164

Lessons from Nature and Bioinspired Fabrication: Mosquito Bite and Lotus Leaf Inspired Superliquiphobic Leather

Gurera, Dev 24 May 2018 (has links)
No description available.
165

Características do processo de ingestão de forragem por cordeiras em pastagem de azevém nos diferentes estádios fenológicos / Characteristics of forage intake process by lambs on italian ryegrass pature at different phenological stages

Camargo, Daniele Gindri 16 December 2008 (has links)
Characteristics of forage intake process by lambs grazing Italian ryegrass pasture (Lolium multiflorum Lam.) were studied, from the hypothesis that different phenological stages of the plant may influence the food gathering process by grazing animals. The experiment was carried out from May to November of 2007 in the Federal University of Santa Maria. Evaluations where made in three occasions within phenological stages of annual ryegrass: Vegetative (11/09), Pre-flowering (14/10) and Flowering (11/11). Eight female lambs (45.0 ± 4.3 kg), Ile de France x Texel crossbreed, with an average age of eight months were utilized. To quantify intake rate and grazing behavior parameters by lambs, grazing tests were conducted. Forage mass, sward height, vertical structure of the pasture and chemical composition of the forage apparently ingested by the lambs were evaluated to determine pasture characteristics. A completely randomized design with three treatments and five replicates in the vegetative stage and six replicates in the other phenological stages was used. Intake rate, bite mass and bite depth were similar (P>0.05) between different stages with a forage on offer of 13.7kg of dry matter per 100kg of live weight. At vegetative stage, bite rate is negatively determined by sward height. At pre-flowering and flowering stages grazing time is positively influenced by sward height. The bite depth is positively influenced by the sward height and negatively influenced by stem bulk density in all phenological stages. The bite rate is negatively influenced by sward height at the vegetative stage of Italian Ryegrass. At the pre-flowering and flowering stage the grazing time is positively influenced by sward height. Grazing time (GT= 27.46 + 0.09day) and number of bites (NB= -175.04 + 9.41day) increased linearly during the pasture cycle. The smaller bite rate was at 135º day after Italian ryegrass emergence and the greater time per bite happened at 146º day. In non limiting forage on offer, lambs maintained the rate of intake constant by increasing bite rate. Among the herbage attributes, the sward height is the most important to determine changes in the grazing behavior of lambs on Italian Ryegrass pasture. / Foram estudadas as características do processo de ingestão de forragem por cordeiras em pastagem de azevém (Lolium multiflorum Lam.), a partir da hipótese de que diferentes estádios fenológicos do pasto influenciam no processo de captura de alimento por animais em pastejo. O experimento foi desenvolvido no período de maio a novembro de 2007 na Universidade Federal de Santa Maria e as avaliações foram realizadas em três datas nos estádios fenológicos do azevém: Vegetativo (11/09), Pré-florescimento (14/10) e Florescimento (11/11). Foram utilizadas oito cordeiras, cruzas Ile de France x Texel com oito meses de idade e 45,0 ± 4,3 kg de peso vivo, em média. Foram realizados testes de pastejo para quantificar a taxa de ingestão de matéria seca (MS) pelas cordeiras e variáveis de comportamento ingestivo de acordo com a metodologia adaptada de PENNING; HOOPER (1985). Na pastagem foram realizadas avaliações de massa de forragem, altura do dossel, estrutura vertical e composição química da forragem aparentemente colhida. O delineamento experimental foi o inteiramente casualizado, com medidas repetidas no tempo, com três tratamentos e cinco repetições no estádio vegetativo e seis nos demais estádios estudados. Com oferta de forragem de 13,7 kg de matéria seca/100 kg de peso vivo, a taxa de ingestão, a massa do bocado e a profundidade de bocado foram semelhantes (P>0,05) nos diferentes estádios. No estádio vegetativo do azevém a altura do pasto influencia negativamente a taxa de bocados. Nos estádios de pré-florescimento e florescimento a altura do pasto influencia positivamente o tempo de alimentação. A profundidade de bocados é positivamente influenciada pela altura do pasto e negativamente pela densidade de colmos no estrato superior. O tempo de alimentação (TA= 27,46 + 0,09 dia) e o número de bocados totais (NBT= -175,4 + 9,41dia) aumentaram linearmente ao longo do ciclo do azevém. O menor número de bocados por unidade de tempo foi realizado no 135º dia após a emergência do azevém e o maior tempo de formação do bocado foi no 146º. Em azevém, com oferta de forragem não limitante ao consumo, o aumento na taxa de bocados é o mecanismo utilizado por cordeiras para manter a taxa de ingestão constante. Dentre os atributos do pasto, sua altura é o de maior importância para determinar mudanças nas variáveis do comportamento ingestivo.
166

Vývoj laserem svařeného Common-Railu s radiálně připojeným snímačem tlaku (RPS) / Development of Laser Welded Common Rail with Radial Connected Pressure Sensor (RPS)

Šantavý, Ivo January 2012 (has links)
This dissertation deals with a development of a laser welded common rail with a radially attached RPS sensor of pressure. The new concept required by Bosch Diesel s.r.o. Jihlava should be more modifiable and it should be easily integrated with the engine compartment. In this dissertation I suggested a number of concepts that I further analysed, verified in appropriate software, developed, and finally narrowed the selection down to the most suitable solution, which is recommended and justified in the conclusion.
167

L'ulcère de Buruli dans un centre de santé rural au Bénin

Debacker, Martine 15 April 2005 (has links)
Notre travail porte sur tous les cas UB enregistrés entre 1997 et 2003 au Centre Sanitaire Nutritionnel Gbemoten (CSNG) de Zagnanado dans la région du Zou au Bénin. Une base de données a été créée et a permis d’analyser divers aspects de l’UB. Ces analyses ont donné lieu à diverses publications dont les résultats essentiels sont repris ci-dessous. Une première publication porte sur 1700 cas consécutifs admis au CSNG entre 1997 et 2001. Ces données nous ont permis d’illustrer l’évolution du nombre des cas d’UB au cours des années, par département et par sous-préfecture. Le nombre de patients UB qui se présentent au centre est fonction de différents facteurs comme par exemple l’ouverture d’autres centres de traitement, l’organisation de campagnes d’information sur l’UB mais aussi de changements dans l’environnement. Au niveau des formes de la maladie, nous avons montré que les formes non ulcérées sont aussi fréquentes que les formes ulcérées. La forme de la maladie est liée au délai à consulter le CSNG. Les atteintes osseuses sont fréquentes et sont présentes chez plus de 13% des cas. Au fil des années, le délai à consulter le CSNG ainsi que la durée de l’hospitalisation ont été fortement réduits, passant de 4 mois à 1 mois dans le premier cas et de 9 mois à 1 mois en ce qui concerne l’hospitalisation. Les personnes ressources à cibler lors des campagnes de sensibilisation sur la maladie ont été identifiées. Il s’agit des anciens malades, qui dans 68% des cas, réfèrent les nouveaux malades au CSNG. Une deuxième publication, portant sur la même période, nous a permis de mettre en évidence pour la première fois des taux d’UB élevés chez les sujets de 60 ans et plus, probablement du fait d’une diminution de leur immunité. Chez les 60 ans et plus, les hommes sont plus à risque de développer un UB que les femmes. Par contre aucune différence dans le risque d’UB en fonction du sexe n’est trouvée chez les moins de 60 ans. Les lésions d’UB prédominent au niveau des membres inférieurs pour tous les groupes d’âge. Du fait de leur petite stature, les enfants ont une répartition des lésions qui touchent tout le corps. Chez les adultes, les femmes présentent plus de lésions que les hommes au niveau de la tête, du cou et du tronc. Les sujets de moins de 15 ans développent souvent des lésions multifocales, associées à des atteintes osseuses. Ces atteintes osseuses constituent les formes graves de la maladie. Notre troisième publication porte sur le suivi des malades au niveau des villages, entre mars 2000 et février 2001, afin de déterminer les taux de récurrences de l’UB. Le taux de récurrence de la maladie est faible (6.1%) pour un temps de suivi des malades allant jusqu’à 7 ans. La majorité des malades soignés au CSNG étaient en bonne santé. Nous n’avons néanmoins pu retrouver qu’un nombre limité de malades. Dans notre quatrième publication, nous avons pu mettre en évidence le développement d’un UB sur le site d’une morsure humaine. La surface de la peau du malade a pu être contaminée par M. ulcerans et la morsure (= traumatisme) a occasionné l’entrée de M. ulcerans dans le derme. Une autre explication plausible est que la morsure ait réactivé un foyer latent de M. ulcerans au niveau du site de la morsure. Notre base de données nous a également permis de contribuer à d’autres études, notamment celles sur l’influence du BCG et de la schistosomiase sur l’UB. Dans les deux cas, nous trouvons une association significative avec les formes graves de l’UB, l’absence de vaccination BCG et la schistosomiase favorisant le développement de formes osseuses. Aucun lien n’a pu être établi entre la présence ou l’absence de l’infection à Schistosoma haematobium et l’UB. Dans la dernière partie de notre travail, nous nous sommes attachés à l’étude de quelques facteurs de risque de l’UB. Nous avons montré que l’UB est essentiellement associé à l’âge, le lieu de résidence et le type d’eau utilisé. Pour les sujets de 5 ans et plus, le risque d’UB est plus élevé chez les sujets vaccinés à la naissance avec le BCG. L’analyse par strate d’âge des sujets âgés de 5 ans et plus, nous a permis de voir que dans le groupe des 50 ans et plus l’influence du type d’eau utilisé est moindre que dans les autres groupes d’âge, laissant envisager qu’un autre facteur entre en jeu : une réactivation de la maladie à la faveur d’une baisse d’immunité. Notre étude démontre que la prise en charge de l’UB doit être pluridisciplinaire et doit pouvoir englober diverses interventions telles que : - les campagnes d’information à la population, - la formation du personnel sanitaire ainsi qu’une implication de l’état, - une bonne prise en charge des malades au niveau des centres de traitement de l’UB en collaboration avec les laboratoires régionaux et internationaux, - la confirmation microbiologique des cas, - la mise en place d’un suivi des malades en s’appuyant sur les structures déjà mises en place pour d’autres maladies, - la mise à disposition des populations de sources d’eau potable (puits, pompes) qui par la même occasion permettront de limiter/diminuer d’autres affections liées à la consommation d’eau non potable, - la poursuite des activités de recherche sur un éventuel vaccin ou une médication appropriée, ainsi que sur le réservoir de M. ulcerans afin de pouvoir mettre en place des stratégies de prévention de la maladie.
168

Efeito do front-plateau na atividade eletromiográfica, no limiar de dor a pressão e na força de mordida de pacientes com mialgia local nos músculos da mastigação: estudo preliminar / Effect of front-plateau on electromyographic activity, pressure pain threshold, and bite strength of patients with local myalgia in mastication muscles: preliminary study

Santos, Elaine Cristina Sousa dos 24 August 2017 (has links)
A dor orofacial compreende todas as dores que envolvem os tecidos moles e mineralizados da cavidade oral e da face, pode ser referida na região da cabeça e/ou pescoço. A etiologia da disfunção temporomandibular (DTM) é multifatorial, são distúrbios musculoesqueléticos que afetam o sistema estomatognático, os músculos mastigatórios e/ou estruturas associadas. Uma disfunção muito prevalente é a dor miofascial. O front-plateau é um dispositivo de resina acrílica instalado nos dentes superiores anteriores, que desoclui os dentes posteriores, proporcionando desprogramação neuromuscular. O objetivo deste estudo foi avaliar a atividade eletromiográfica, o limiar de dor à pressão (LDP) dos músculos temporal e masseter, e a força de mordida molar máxima de participantes com dor miofascial, antes e após a instalação da placa anterior \"front-plateau\". As participantes foram recrutadas e atendidas na Clínica de Dor Orofacial do DAPE da FORP-USP. Para tanto, foram avaliadas 22 mulheres entre 20 e 60 anos. As participantes foram submetidas inicialmente aos exames de eletromiografia (EMG), eletromiógrafo MyoSystem-Br1, limiar de dor a pressão (LDP) algômetro Kratos® e foi aferida força de mordida molar máxima (FMM) por meio do dinamômetro Kratos® IDDK. Foram formados dois grupos, no grupo 1 (G1) 11 participantes usaram o front-plateau por sete dias, 16 horas nos três primeiros dias e por oito horas nos próximos quatro dias, sendo que o tratamento foi interrompido após este período. O grupo 2 (G2), com 11 participantes, iniciou o tratamento idem ao G1 e após sete dias continuaram usando o front-plateau por oito horas diárias por mais três semanas, totalizando 1 mês de uso. Após o tratamento, as participantes dos dois grupos foram novamente avaliadas quatro semanas após a primeira avaliação. Os dados foram analisados com auxílio do software R (R® Foundation for Statistical Computing, Áustria). Os valores reais ou transformados das variáveis foram comparados entre os tratamentos, dias de avaliação e sua interação pela Analise de Variância (ANOVA) em um delineamento interamente casualizado com medidas repetidas no tempo. Para as variáveis que apresentaram diferença estatística, as médias foram comparadas pelo pós-teste de Tukey (p<0,05) e os dados apresentados como a média ± o erro padrão (EP). Foi encontrado relevância estatística em todas as variáveis das análises feitas pelo algômetro durante a utilização do front-plateau, havendo diminuição da sensibilidade dolorosa e aumento do LDP em todos os músculos analisados. Não houve qualquer alteração estatisticamente significativa na FMM no período de utilização do front plateau. Na eletromiografia foi encontrados valores significativos nos padrões posturais de lateralidade direita (LD) e lateralidade esquerda (LE) e mastigação de uva-passa (MU) entre os grupos. Podemos concluir que durante o período de uso do front-plateau houve elevação do LDP (reduzindo a sensibilidade à dor) sendo que após a interrupção do tratamento essa variável retornou às condições iniciais; Na EMG foi observado diminuição do estímulo elétrico para padrões posturais de LD, LE e MU. Porém a FMM não foi modificada durante a utilização do dispositivo. / Orofacial pain comprises all pains involving the soft and mineralized tissues of the oral cavity and face, it can be felt in the region of the head and/or neck. The etiology of temporomandibular dysfunction (TMD) is multifactorial. Its defined as musculoskeletal disorders that affect the stomatognathic system, the masticatory muscles and/or associated structures. A very prevalent dysfunction is myofascial pain. Front-plateau is an acrylic resin device installed in the anterior superior teeth, which separates the posterior teeth, providing neuromuscular deprogramming. The purpose of this study was to assess the electromyographic activity, the pain threshold at the temporal and masseter muscles, and the maximum molar bite strength of participants with myofascial pain, before and after the installation of the front-plateau. Participants were recruited and cared at the FORP-USP DAPE Orofacial Pain Clinic. Twenty two women between 20 and 60 years old were evaluated. The participants were initially submitted to electromyography (EMG) tests, MyoSystem-Br1 electromyograph, pressure pain threshold (PPT), Kratos® algometer, and maximal molar bite force (MMB), Kratos® IDDK dynamometer. Two groups were formed, in group 1 (G1) 11 participants used the front-plateau for seven days, 16 hours on the first three days and for eight hours on the next four days, and treatment was stopped after this period. Group 2 (G2), with 11 participants, started the treatment identical to G1 and after seven days they continued using the front-plateau for eight hours daily for another three weeks, totaling one month of use. After treatment, participants from both groups were reassessed four weeks after the first evaluation. The data were analyzed using R software (R® Foundation for Statistical Computing, Austria). The real or transformed values of the variables were compared between the treatments, evaluation days and their interaction by the Analysis of Variance (ANOVA) in an inter randomized design with repeated measures in time. For the variables that presented statistical difference, the means were compared by Tukey\'s post-test (p <0.05) and the data presented as the mean ± standard error (SE). A statistically significant value was found in all the variables analyzed by the algometer. There was a decrease in pain sensitivity and an increase in the pressure pain threshold (PPT) in all muscles analyzed. There was no statistically significant change in the maximum bite force during the period of use of the front-plateau. In electromyography, significant values were found in the postural patterns of right laterality (RL) and left laterality (LL) and chewing of raisins (CR). We can conclude that during the period of use of the front-plateau there was elevation of the PPT (reducing the sensitivity to pain) returning to the initial conditions after removal of the device; It was observed a decrease in the electrical stimulus for postural patterns of RL, LL and CR. However, the MMB was not modified during the use of the device.
169

O impacto da síndrome da fibromialgia na musculatura mastigatória e cervical: análise eletromiográfica, ultrassonográfica, força de mordida e eficiência mastigatória / Impact of fibromyalgia syndrome on the chewing and cervical muscles: electromyographic analysis, ultrasound, strength of bite and chewing efficiency

Nepomuceno, Victor Rodrigues 04 May 2016 (has links)
A Síndrome da fibromialgia é caracterizada pela presença de dor muscular crônica e difusa em pelo menos onze pontos do corpo humano denominados de tender points, rigidez matinal, fadiga, distúrbios do sono, sintomatologia dolorosa extensa na face, que se manifesta principalmente nos músculos mastigatórios, articulação temporomandibular e na região auricular. O objetivo desta pesquisa foi analisar os músculos mastigatórios (masseter e temporal) e cervicais (esternocleidomastoideo e trapézio) em mulheres com diagnóstico de síndrome da fibromialgia. Participaram dessa pesquisa sessenta e oito mulheres na faixa etária entre 40 a 60 anos de idade, distribuídas em dois grupos distintos: GF: síndrome de fibromialgia (n=34) e GC: controle saudável (n=34). O eletromiógrafo Myosystem-Br1 foi utilizado para analisar a atividade EMG. As imagens das espessuras dos músculos mastigatórios e cervicais foram adquiridas pelo ultrassom Sonosite Titan. A força de mordida molar máxima foi obtida por meio de dinamômetro digital Kratos. Os dados da atividade EMG, espessura muscular e força de mordida molar foram tabulados, normalizados e submetidos à análise estatística (SPSS 21.0). Houve diferença estatística significante (p <= 0,05) entre GF e GC em todas as condições posturais mandibulares, na mastigação (habitual e não habitual), espessura muscular e força de mordida molar, com dados médios menores para GF. Baseados nos resultados desta pesquisa, os autores concluíram que mulheres com síndrome da fibromialgia apresentaram alterações no sistema estomatognático / Fibromyalgia syndrome is characterized by chronic and diffuse muscle pain in at least eleven points of the human body (tender points), morning stiffness, fatigue, sleep disturbances, extensive pain symptoms in the face, which is mainly manifested in the masticatory muscles, temporomandibular joint and ear region. The aim of this study was to analyze the masticatory (masseter and temporal) and cervical (sternocleidomastoid and trapezius) muscles in women with diagnosis of fibromyalgia syndrome. Sixty-eight women aged between 40 and 60 years participated in this research. They were divided into two distinct groups: FG: fibromyalgia syndrome (n = 34) and CG: healthy control (n = 34). The Myosystem-Br1 electromyography was used to analyze the EMG activity. The thicknesses of the masticatory and neck muscles were acquired by ultrasound Sonosite Titan. The maximum molar bite force was obtained using a digital force gauge Kratos. The data of EMG activity, muscles thickness and maximal molar bite force were tabulated, standardized and subjected to statistical analysis (SPSS 21.0). There were statistically significant differences (p<= 0.05) between FG and CG at all mandibular postural conditions, chewing, muscle thickness and molar bite force, with lower average data for FG. Based on the results of this research, the authors concluded that women with fibromyalgia syndrome have alterations in the stomatognathic system
170

Reação eosinofílica decorrente dos componentes salivares do mosquito Aedes aegypti: caracterização do infiltrado inflamatório. / Eosinophilic reaction resulting from salivary components of the mosquito Aedes aegypti: characterization of the inflammatory infiltrate.

Henrique, Maressa de Oliveira 08 December 2016 (has links)
Durante o repasto sanguíneo, os mosquitos hematófagos inoculam os componentes de seu coquetel salivar na pele do hospedeiro podendo causar reações inflamatórias. Existem vários trabalhos que descrevem o infiltrado celular após a picada de mosquito utilizando abordagens clássicas de histologia. No entanto, são escassos os trabalhos que avaliem esse infiltrado celular de maneira quantitativa/qualitativa com técnicas mais modernas. Adicionalmente, a literatura científica carece de modelos simples para o estudo das moléculas envolvidas na migração celular induzida pelos componentes salivares de mosquitos. Diante disto, em um primeiro momento estudamos o infiltrado celular na pele da orelha decorrente da picada do mosquito Aedes aegypti em animais sensibilizados ou não com o extrato da glândula salivar (EGS) destes mosquitos utilizando a técnica de citometria de fluxo. Observamos que enquanto o edema em animais não sensibilizados alcança um pico 6 horas após a exposição aos mosquitos, o mesmo só acontece após 24 horas nos animais sensibilizados, persistindo ainda até 72 horas. A fenotipagem das células imunes presentes no tecido por citometria de fluxo mostrou a complexidade de populações celulares presentes na reação inflamatória à picadas de mosquito, destacando-se o infiltrado de linfócitos B, neutrófilos e eosinófilos que ocorreram em ambos os grupos, porém de maneira mais intensa após 24 horas no grupo sensibilizado. Dentre essas populações, os eosinófilos foram as células que proporcionalmente mais aumentaram em relação àquelas encontradas na orelha de animais naïve. Em uma segunda abordagem, desenvolvemos um modelo de inflamação eosinofílica na cavidade peritoneal de camundongos inoculados com o EGS de A. aegypti. Utilizando esse modelo, fomos capazes de mostrar que a migração de eosinófilos se deve a atividade dos componentes salivares do mosquito e não a uma possível contaminação por endotoxina presentes na preparação. Além disso, a desnaturação das proteínas do EGS aboliu sua capacidade de induzir migração de eosinófilos, reforçando a importância da integridade das moléculas salivares nesse processo. Finalmente, mostramos que a migração de eosinófilos nesse modelo é dependente de IL-5 e de produtos da 5-lipoxigenase. Em conjunto, esses dados contribuem para a caracterização da resposta inflamatória do hospedeiro aos componentes salivares do mosquito A. aegypti e para o entendimento das moléculas envolvidas na reação eosinofílica presente em indivíduos sensibilizados. / During their blood feeding, hematophagous mosquitoes inoculate the components of their salivary cocktail in the host skin causing inflammatory reactions. Several works describe the cellular infiltrate following the mosquito bites using classical histological approaches. However, only few studies evaluate the cellular infiltrate in a quantitative/qualitative manner employing recent techniques. Additionally, the scientific literature lacks simple models to study the molecules involved in cell migration induced by the salivary components of mosquitoes. In view of this facts, we first studied the cellular infiltrate in the skin of the ear following Aedes aegypti mosquito bites in animals sensitized or not with the salivary gland extract (SGE) of these mosquitoes, using the flow cytometry technique. We observed that, while the swelling reached a peak at 6 hours after exposure to mosquitoes in non-sensitized animals, the same occurred only after 24 hours in sensitized animals, and the edema still persisted at 72 hours. Immune cell phenotyping of the tissue by flow cytometry showed the complexity of cell populations present in the inflammatory reaction to mosquito bites, especially the infiltration of B lymphocytes, neutrophils and eosinophils that occurred in both groups, but more intensely after 24 hours in the sensitized group. Among these populations, eosinophils were the cells that most increased proportionally compared those found in the ear of naïve animals. In a second approach, we have developed a model of eosinophilic inflammation in the peritoneal cavity of mice inoculated with the A. aegypti SGE. Using this model, we were able to show that the migration of eosinophils was due to the activity of the mosquito salivary components and not to a possible endotoxin contamination of the preparation. Moreover, the denaturation of SGE proteins abolished its ability to induce eosinophil migration, underscoring the importance of the integrity of salivary molecules in this process. Finally, we showed that the eosinophil migration in this model is dependent on IL-5 and 5-lipoxygenase products. Together, these data contribute to the characterization of the host inflammatory response to salivary components of A. aegypti mosquitoes and to the understanding of the molecules involved in this eosinophilic reaction in sensitized individuals.

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