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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.
671

Medical Community Distrust and the Influenza Vaccination Rates of Black Americans

Winston, Kenyatte Irby 01 January 2016 (has links)
Black Americans experience influenza vaccination rates that are lower than the rates of other ethnic groups. Low influenza vaccination rates among the Black community are associated with higher influenza infection rates, influenza-related hospitalizations, and higher influenza mortality rates. There is a belief within the Black American community that the medical establishment does not have the Black American patient in its best interest, leading to feelings of distrust. The purpose of this study was to determine if the distrust of the medical community is a relevant factor in the low influenza vaccination rates of Black Americans aged 18 and older in Baltimore, Maryland. The study also examined the belief that the influenza vaccine causes the flu and the effect this belief may have on influenza vaccination rates. The public health critical race theory served as the framework for the study. Previously validated survey instruments, the Health Care System Distrust Scale and the Adult Influenza Immunization Survey, were obtained with permission and used to collect data from the members of a Baltimore city church. The study used chi-square analysis, multivariable logistic regression, and narrative discussion to address the research questions and analyze the data of 105 completed surveys. Results of the study determined that distrust of the medical community was not a relevant factor in the influenza vaccination rates of study participants, and that participants' vaccination status was influenced by factors other than distrust. Implications for social change included improving the influenza vaccination rate among Black Americans and decreasing their influenza mortality rates.
672

Immunoglobulin Therapy and Primary Immunodeficient Patients' Health-Related Quality of Life and Well-Being

Heckman, Niedre 01 January 2018 (has links)
Individuals born with primary immune deficiency diseases (PIDD) have a dysfunctional immune system, and many are treated by lifelong injections of immunoglobulin therapy. Studies have shown that these patients have low health-related quality of life (HRQOL) and well-being (WB) and that these outcomes might be improved by the availability of therapy innovated according to preferences for fewer needle sticks or a shorter infusion time. Regulators at the U.S. Food and Drug Administration (FDA) have approved therapies innovated per these preferences. However, there is limited data demonstrating how these innovations impact HRQOL and WB. Using the biopsychosocial model, the purpose of this cross sectional quantitative study was to evaluate whether patients with PIDD using therapies innovated for fewer needle sticks or a shorter infusion time had a higher mean HRQOL and WB compared to those who were not. The study included 153 patients who completed the Patient Reported Outcomes Measurement Information System (PROMIS)-29 survey. The dependent variables were HRQOL and WB measured by PROMIS-29, and the independent variables were the medical product innovations. Independent samples t tests results showed mean PROMIS-29 scores were not statistically different (p > .05). This suggests patients were optimized according to their treatment preference. A subgroup of patients who had taken the PROMIS-29 survey more than once concurrent with switching to a therapy aligned with patient preferences showed improved HRQOL and WB. These findings have implications for positive social change in that seeking the patient's voice to inform medical product innovation and FDA regulatory decision-making has potential to improve biopsychosocial outcomes.
673

Combining Systems Methodologies to Reduce Allergen-Related Food Recalls

Sweney, Jill Marie 14 May 2015 (has links)
The risk of poor food safety is a major focus for managers in the food manufacturing industry. Despite industry-led and regulatory efforts to improve the overall food safety of US packaged consumer foods, product recalls and market withdrawals are increasing. This is especially true for the most frequent cause for food recall: the undeclared allergen. With industry trends leaning toward adoption of third-party food safety management certifications, a popular food safety code from the Safe Quality Foods Institute is evaluated using Systems Analysis. Three changes to the food safety code are proposed to address three of the top causes for an allergen-related recall in the United States. In practice, the SQF code should make better use of control theory to reduce delays in production monitoring activities, should make better use of purposeful action in the implementation of a HACCP plan to ensure continuing validity of the plan, and SQFI needs to consider adding an organizational assessment for food safety culture.
674

Development, Expansion and Role of Myeloid-Derived Suppressor Cells in Post-Sepsis Immune Suppression

Alkhateeb, Tuqa 01 August 2020 (has links)
Myeloid-derived suppressor cells (MDSCs) numbers increase significantly in sepsis and are associated with high mortality rates. These myeloid cell precursors promote immunosuppression, especially in the late (post sepsis) stage. However, the mechanisms that underlie MDSC expansion and programming are not completely understood. To investigate these mechanisms, we used a cecal-ligation and puncture (CLP) mouse model of polymicrobial sepsis that progresses from an early/acute proinflammatory phase to a late/chronic immunosuppressive phase. Previous studies in our laboratory showed that microRNA (miR)-21 and miR-181b elevate levels of the transcription factor nuclear factor 1 (NFI-A) that promotes MDSC expansion. We report here that miR-21 and miR-181b regulate NFI-A expression via a post-transcriptional regulatory mechanism by recruiting RNA-binding proteins HuR and Ago1 to stabilize NFI-A mRNA, thus increasing its protein levels. Studies in our laboratory also showed that inflammatory mediator S100A9 accumulates in the nucleus in Gr1+CD11b+ myeloid precursors in the later phases of sepsis and is necessary for their expansion and programming into immunosuppressive MDSCs. We demonstrate here that nuclear S100A9 associates with specific transcription factors that activate miR-21 and miR-181b expressions. In our final manuscript, we uncover another layer of the mechanisms of MDSC expansion and programming. We found that long non-coding RNA (lncRNA) Hotairm1 binds to and recruits S100A9 to the nucleus to program Gr1+CD11b+ myeloid precursors into MDSCs in the later phases of sepsis. Together, our results reveal three regulatory layers involving NFI-A, S100A9 and Hotairm1 in the pathway leading to MDSCs development in sepsis and suggest that therapeutically targeting these molecular switches might improve sepsis survival.
675

Increased inflammatory response is associated with less favorable functional results 5 years after total knee arthroplasty

Lützner, Jörg, Beyer, Franziska, Lützner, Cornelia, Thomas, Peter, Summer, Burkhard 19 March 2024 (has links)
Purpose Allergy against implant materials is discussed controversially and still not fully understood. Despite these controversies, a relevant number of patients receive hypoallergenic knee implants. The aim of this study was to compare a new coating system with the standard implant in total knee arthroplasty (TKA). Additionally, the influence of proinflammatory cytokines on patient-reported outcome measures (PROMs) was investigated. Methods 120 patients without known metal allergy and without previous metal implants were included. The patients were randomized to receive a coated or standard TKA of the same knee system. 105 patients completed the 5 year follow-up. Patient-reported outcome measures (PROMs) including knee function (Oxford Knee Score, OKS), quality of life (SF36) and UCLA activity scale were assessed. Additionally, several cytokines with a possible role in implant allergy were measured in patient`s serum (IL-1beta, IL-5, IL-6, IL-8, IL-10, IP-10, IFN γ, TNF α). Group comparison was performed using Mann–Whitney U test for continuous values and chi-square test for categorical values. Results There were no differences in PROMs between both groups at any follow-up. The majority of patients demonstrated no elevation of the measured blood cytokines. The blood cytokine pattern after 5 years demonstrated no differences between study groups. There was a significant association between elevated IL-8 values and worse results in the overall OKS (p = 0.041), the OKS function component (p = 0.004), the UCLA activity scale (p = 0.007) and the physical component of SF36 (p = 0.001). Conclusion There were no problems with the new coating during mid-term follow-up and no differences in PROMs between coated and standard TKA. Patients with an increased inflammatory response demonstrated worse functional results, regardless of the implant. Level of evidence I. Clinical trial registration The study protocol was registered in the US National Institutes of Health’s database (http:// www.clini caltr ials. gov) registry under NCT00862511.
676

Sensitivity of airway nociceptor neurons to immune signals in Type 2 inflammation. Sensibilité des neurones nocicepteurs aux signaux immunitaires dans l’inflammation de type 2

Crosson, Théo 02 1900 (has links)
Les neurones nocicepteurs jouent un rôle clé dans la défense de l’organisme. Dans le cas des réactions inflammatoires, ils initient des réflexes protecteurs tels que la toux, les vomissements, où les démangeaisons, et participent à la régulation de plusieurs mécanismes physiologiques, notamment la réponse immunitaire. Ils jouent ainsi un rôle prépondérant dans l’inflammation de type 2, souvent associée aux allergies. Mais les mécanismes qui permettent l’activation de ces neurones dans ce contexte sont encore mal connus. Au cours de ce projet de recherche, nous avons exploré la capacité des neurones nocicepteurs à détecter les signaux immunitaires spécifiquement associés à l’asthme. Nous avons ainsi identifié les caractéristiques des nocicepteurs des voies aériennes. Nous avons également démontré leur sensibilité aux allergènes grâce à l’expression du récepteur aux immunoglobulines de type E, FcεR1, ainsi que leur capacité à modifier leur transcriptome en réponse aux cytokines IL-4 et IL-13. Ces travaux soutiennent l’importance de la communication entre systèmes nerveux et immunitaires, et mettent en évidence de nouvelles cibles pour limiter la contribution neuronale aux réactions allergiques. / Nociceptor neurons play a major role in organism defense. In the context of inflammation, they initiate protective reflexes such as cough, vomiting, or itch, and participate in the regulation of various physiological mechanisms, including the immune response. They notably participate in type 2 inflammation, often associated with allergies. But the mechanisms driving the activation of nociceptor neurons in this context are still elusive. During this research project, we investigated the ability of nociceptor neurons to sense immune signals specifically associated with asthma. We identified the characteristics of airway innervating nociceptors. We also demonstrated their sensitivity to allergens through the expression of the Immunoglobulin E receptor FcεR1, as well as their ability to change their transcriptome in response to IL-4 and IL-13. This work supports the importance of bidirectional communication between the nervous and immune systems and unravels new targets to regulate neuronal contribution to inflammation.
677

Metodologías bioanalíticas para el diagnóstico in vitro de alergia a antibióticos ß-lactámicos

Juárez Rodriguez, María José 12 July 2022 (has links)
[ES] Los fármacos pertenecientes a la familia de los ß-lactámicos son los antibióticos más usados en todo el mundo. Estudios recientes revelan que hasta un 10% de la población refiere haber presentado síntomas alérgico, esta porción de la población se considera "alérgica". En el diagnóstico de la alergia a antibióticos ß-lactámicos existen varios tipos de pruebas que sirven para orientar y confirmar la presencia de una alergia, clasificadas como ensayos in vivo e in vitro. En lo que se refiere a los ensayos in vivo, la detección de los procesos alérgicos más comunes se realiza mediante pruebas de exposición oral controladas, y pruebas intraepidérmicas e intradérmicas. No obstante, estas pruebas tienen sus limitaciones como es el riesgo de inducir reacciones alérgicas sistémicas graves. Por todo ello, su práctica requiere personal entrenado. Este requisito limitan la realización de este tipo de pruebas a centros hospitalarios especializados. La aplicación y desarrollo de técnicas de diagnóstico in vitro tiene como objetivo llegar a un diagnóstico de la alergia sin riesgos para el paciente. Entre las distintas pruebas serológicas y celulares que se pueden emplear, la detección de IgE específica es una de las más extendidas debido a que, dada su sensibilidad y especificidad, y mayor seguridad. Los sistemas de diagnóstico in vitro actuales utilizan una instrumentación analítica cara y de gran tamaño, así como materiales desechables caros, manejados por personal cualificado, por lo que este tipo de pruebas se realizan únicamente por servicios de alergia y/o análisis clínicos de grandes centros sanitarios. En consecuencia, hay una necesidad de desarrollar nuevos métodos de diagnóstico que cumplan los requisitos de sensibilidad, rapidez, sencillez, multiplexado y portabilidad, a un precio reducido para su implantación en todo tipo de laboratorios clínicos de los diferentes niveles de atención sanitaria. Por este motivo, en esta tesis doctoral se plantea como objetivo principal la puesta a punto de un inmunoensayo múltiple, utilizando la tecnología de disco compacto para la detección y cuantificación in vitro de niveles de IgE específica a un amplio espectro de antibióticos ß-lactámicos en muestras de suero humano. Las limitaciones más críticas para la determinación de IgE específica multianalito mediante métodos inmunoquímicos son las relacionados con la sensibilidad y selectividad. Por lo tanto, una parte importante de la tesis se ha centrado en la preparación y caracterización de un panel antígenos ß-lactámicos, selección de inmunoreactivos, formato y estudio de diferentes parámetros claves del inmunoensayo. Otra parte importante de la tesis se ha enfocado en abordar la mejora de la reproducibilidad de los resultados. La estrategia ha consistido en estudiar diferentes sistemas de calibración con el objetivo de estandarizar la cuantificación de los métodos in vitro de diagnóstico de este tipo de alergias. Para ello, se han evaluado las prestaciones de la calibración homóloga, heteróloga y el uso de un patrón interno, comparado sus prestaciones analíticas (relación señal ruido, sensibilidad, reproducibilidad, etc.) con el sistema de referencia. Finalmente, la validación del inmunoensayo se realizó con un conjunto de 101 muestras de suero de pacientes y controles. Los resultados obtenidos han sido comparados con los obtenidos mediante las técnicas de referencia, mostrando una mejor sensibilidad, especificidad, precisión, y linealidad. La capacidad múltiplex de la tecnología de disco compacto permitió llevar a cabo paralelamente estudios de reactividad cruzada frente a diferentes antibióticos ß-lactámicos esclareciendo el patrón de reconocimiento de los pacientes. En esta línea de trabajo, el uso de otras estrategias de conjugación de haptenos ha resultado en la mejora de la sensibilidad clínica del ensayo, identificando nuevos epítopos / [CA] Els fàrmacs que pertanyen a la família dels beta-lactams, són els antibiòtics d'us més estès a tot el món. Estudis recents posen de manifest que fins un 10% de la població ha presentat símptomes d'al·lèrgia, essent considerats població al·lèrgica als beta-lactams. En el diagnòstic de l'al·lèrgia front aquest tipus d'antibiòtics, existeixen diferents tipus de proves que serveixen per orientar i confirmar la presència d'una al·lèrgia, classificades com assajos in vivo i in vitro. Pel que fa als assajos in vivo, la detecció dels processos al·lèrgics més comuns es realitza mitjançant proves d'exposició oral controlades, i proves intra-epidèrmiques i intradèrmiques. No obstant això, aquestes proves tenen les seues limitacions com és el risc d'induir reaccions al·lèrgiques sistèmiques greus. Per tot això, la seua pràctica requereix personal entrenat. Aquests requisits limiten la realització d'aquesta mena de proves a centres hospitalaris especialitzats. L'aplicació i desenvolupament de tècniques de diagnòstic in vitro té com a objectiu arribar a un diagnòstic de l'al·lèrgia sense riscos per al pacient. Entre les diferents proves serològiques i cel·lulars que es poden emprar, la detecció d'IgE específica és una de les més esteses donada la seua sensibilitat, especificitat, i major seguretat. Els sistemes de diagnòstic in vitro actuals utilitzen una instrumentació analítica cara i de gran grandària, així com materials d'un sol ús també cars, que requereixen de personal qualificat, per la qual cosa aquest tipus de proves es realitzen únicament per serveis d'al·lèrgia i/o anàlisis clíniques de grans centres sanitaris. En conseqüència, hi ha una necessitat de desenvolupar nous mètodes de diagnòstic que complisquen els requisits de sensibilitat, rapidesa, senzillesa, multiplexatge i portabilitat, a un preu reduït per a la seua implantació en tota mena de laboratoris clínics dels diferents nivells d'atenció sanitària. Per aquest motiu, en aquesta tesi doctoral es planteja com a objectiu principal la posada a punt d'un immunoassaig múltiple, utilitzant la tecnologia de disc compacte per a la detecció i quantificació in vitro de nivells d'IgE específica a un ampli espectre d'antibiòtics ß-lactáms en mostres de sèrum humà. Les limitacions més crítiques per a la determinació d'IgE específica multianàlit mitjançant mètodes inmunoquímics estan directament relacionades amb la sensibilitat i selectivitat. Per tant, una part important de la tesi s'ha centrat en la preparació i caracterització d'un panell antígens ß-lactáms, selecció d'inmunoreactius, del format d'assaig i estudi de diferents paràmetres claus de l'immunoassaig. Una altra part important de la tesi s'ha enfocat a abordar la millora de la reproductibilitat dels resultats. L'estratègia ha consistit a estudiar diferents sistemes de calibratge amb l'objectiu d'estandarditzar la quantificació dels mètodes in vitro de diagnòstic d'aquesta mena d'al·lèrgies. Per a això, s'han avaluat les prestacions del calibratge homòleg, heteròleg i l'ús d'un patró intern, comparant les seues prestacions analítiques (relació senyal soroll, sensibilitat, reproductibilitat, etc.) amb el sistema de referència. Finalment, la validació de l'immunoassaig es va realitzar amb un conjunt de 101 mostres de sèrum de pacients i controls. Els resultats obtinguts han sigut comparats amb els obtinguts mitjançant les tècniques de referència, mostrant una millor sensibilitat, especificitat, precisió, i linealitat. La capacitat múltiplex de la tecnologia de disc compacte va permetre dur a terme paral·lelament estudis de reactivitat creuada enfront de diferents antibiòtics ß-lactáms esclarint el patró de reconeixement dels pacients. En aquesta línia de treball, l'ús d'altres estratègies de conjugació d'haptens ha resultat en la millora de la sensibilitat clínica de l'assaig, identificant nous epítops / [EN] ß-lactam antibiotics are one of the most widely used antimicrobials worldwide. However, up to 10% of the population reports having presented allergic symptoms derived from their consumption. Consequently, this portion of the population is considered "allergic". In the diagnosis of allergy to ß-lactam antibiotics there are several types of tests that serve to orient and confirm the presence of an allergy. These diagnostic methods are classified as in vivo and in vitro assays. Regarding in vivo tests, the most standardized tests are the provocation, prick and intradermal test. The aim of these assays is to observe the response produced by the different beta-lactam antibiotics in the patient after oral or cutaneous administration. Despite their wide use, these tests have their limitations, such as the risk of inducing severe systemic allergic reactions. Therefore, their practice requires specialized professionals for their indication, performance and interpretation. This requirement limit the performance of this type of test to specialized hospitals. The use and development of in vitro diagnostic techniques can overcome these disadvantages and allow the diagnosis of allergy without risks. In vitro assays are less invasive and therefore neither pose a risk of adverse reactions. Among the different serological and cellular tests that can be used, the detection of specific IgE is one of the most widespread due to its sensitivity and specificity. Current in vitro diagnostic systems use expensive and bulky analytical instrumentation and high-cost single-use materials, handled by qualified professionals. Therefore, such tests are performed only by allergy and/or clinical analysis services of hospitals or by companies specialized in clinical diagnostics. Consequently, there is a need to develop new diagnostic methods that can be implemented in all types of clinical laboratories at diverse levels of health care, meeting the requirements of sensitivity, speed, simplicity, multiplexing and portability at a reduced price. For this reason, the main objective of this doctoral thesis is the development of a multiplex immunoassay using compact disc technology for the detection and quantification of specific IgE levels to a wide variety of ß-lactam antibiotics in human serum samples. The most crucial limitations for the determination of multianalyte specific IgE by immunochemical methods are those related to sensitivity and selectivity. Hence, an important part of the thesis has been focused on the preparation and characterization of a pool of beta-lactam antigens, selection of immunoreagents, format and optimization of different critical parameters of the immunoassay. Another important aspect of the thesis has been focused on improving the reproducibility of the results. The strategy consisted of studying different calibration systems with the aim of standardizing the quantification of in vitro diagnostic tests for this type of allergy. To achieve that goal, the performance of homologous and heterologous calibration and the use of an internal standard have been evaluated, comparing their analytical performance (signal-to-noise ratio, sensitivity, reproducibility, etc.) with the reference system. Finally, the validation of the immunoassay was performed with a total of 101 serum samples from patients and controls. The results obtained have been compared with those obtained using the reference techniques, showing improved sensitivity, specificity, precision, and linearity. The multiplex capability of the compact disc technology allowed carrying out parallel cross-reactivity studies against different beta-lactam antibiotics both from the penicillin family and from other families, elucidating the recognition profile. Following this working line, the use of other hapten conjugation strategies improved clinical sensitivity of the assay by identifying new epitopes. / Juárez Rodriguez, MJ. (2022). Metodologías bioanalíticas para el diagnóstico in vitro de alergia a antibióticos ß-lactámicos [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/184011 / Premios Extraordinarios de tesis doctorales
678

Exposition cumulée aux contaminants de l'air intérieur susceptibles d'induire des affections respiratoires chroniques de l'enfant / Cumulative exposure to indoor air contaminants known or suspected to induce chronic respiratory affections in children

Dallongeville, Arnaud 03 July 2015 (has links)
Depuis quatre décennies, la prévalence des affections respiratoires chroniques de l'enfant a considérablement augmenté dans les pays développés. Les conditions de survenue de ces affections sont complexes, mais de nombreux travaux suggèrent la contribution importante de l'exposition par inhalation aux polluants de l'air intérieur. Dans ce contexte, cette thèse vise à évaluer l’exposition cumulée à une gamme de polluants chimiques et biologiques de l’air intérieur dans un échantillon donné de logements. Il a également pour objectif de créer une typologie des logements en fonction de leur multi-contamination, et vise à construire des modèles explicatifs des concentrations des polluants en fonction des caractéristiques de l’habitat et des habitudes de vie des occupants.Une enquête environnementale a été menée dans 150 logements issus de la cohorte Pélagie, suivie en Bretagne depuis 2002. Des prélèvements ont permis de mesurer la concentration de 8 aldéhydes, 4 THM, 22 autres COV, 9 COSV et 4 genres de moisissures dans l’air de ces logements. Celles-ci, ainsi que 4 allergènes ont également été dosés dans des échantillons de poussières. Les paramètres d’ambiance (température, humidité relative et dioxyde de carbone) ont été mesurés. Un questionnaire renseigné par les familles a permis de collecter des informations sur les logements et leurs occupants : structure et historique du bâtiment, revêtements, ménage, chauffage, aération, utilisation de certains produits ou réalisation d’activités particulières. Ces données ont été analysées par des approches statistiques multivariées, et des modèles de régression linéaire et logistique ont été mis en oeuvre pour relier les concentrations des contaminants aux caractéristiques des logements. Ces mesures ont mis en évidence une contamination importante et systématique des logements par une grande part des contaminants chimiques et biologiques, à des niveaux parfois élevés au regard d’études comparables et des valeurs guides lorsqu’elles existent. Des analyses en composantes principales ont permis de mettre en évidence des sous-groupes de composés qui ont pu être interprétés en termes de sources, et de sélectionner un certain nombre de composés traceurs représentatifs de chaque sous-groupe. Une analyse factorielle multiple a permis de répartir les logements en 7 classes, chacune présentant un profil de multi-contamination particulier. Enfin, les modèles de régression linéaire et logistique construits pour les composés traceurs permettent d’expliquer entre 5 et 60% de la variabilité des concentrations, et mettent en évidence la multiplicité des sources, l’importance de la description précise des environnements intérieurs, et l’impact des paramètres d’ambiance sur ces concentrations. Ce travail décrit donc une contribution importante à l’évaluation des expositions aux contaminants de l’air intérieur et fournit un certain nombre d’éléments quant à la prédiction des expositions dans les environnements intérieurs. / For the last four decades, the prevalence of chronic respiratory affections in children has increased dramatically in developed countries. Occurring conditions of these affections are complex, but many studies suggest the important contribution of inhalation exposure to indoor air pollutants. In this context, this thesis aims to assess the cumulative exposure to a range of chemical and biological pollutants in indoor air in a given sample of dwellings. It also aims to create a typology of these dwellings based on their multi-contamination, and to build explanatory models for concentrations of pollutants based on characteristics of the dwellings and lifestyle of the occupants. An environmental survey was conducted in 150 dwellings from the Pelagie cohort, followed in Brittany since 2002. We measured the concentration of 8 aldehydes, 4 THMs, 22 other VOCs, 9 SVOCs and 4 mold genera in the air of these dwellings. Molds as well as four allergens were also measured in dust samples. Ambient parameters (temperature, relative humidity and carbon dioxide) were also measured. A questionnaire completed by families allowed collecting information on dwellings and their occupants: structure and history of the building, wall and floor coatings, cleaning, heating and ventilation habits, use of certain products or performing specific activities. These data were analyzed by multivariate statistical approaches, and linear and logistic regression models were used to link the concentrations of the contaminants with the housing characteristics. These measures showed an important and systematic contamination of the dwellings by a large amount of both chemical and biological contaminants, sometimes at relatively high levels regarding comparable studies and guideline values when they exist. Principal components analysis allowed to identify subgroups of compounds that could be interpreted in terms of sources, and to select representative compounds of each subgroup. A multiple factor analysis was used to classify the dwellings into 7 categories, each with a special multi-contamination profile. Finally, linear and logistic regression models built for the representative compounds explained between 5 and 60% of the variability of the concentrations, and highlighted the multiplicity of sources, the importance of a precise description of indoor environments, and the impact of the ambient parameters on these concentrations. This work thus describes an important contribution to the exposure assessment to indoor air contaminants and provides elements for prediction of exposures in indoor environments.
679

Peptiderge Mediatoren und ihr Beitrag zur Pathophysiologie entzündlicher Erkrankungen

Groneberg, Jan David Alexander 24 March 2004 (has links)
Peptiderge Mediatoren sind neben ihrer Funktion bei der Aufrechterhaltung der körpereigenen Homöostase unter physiologischen Bedingungen auch bei der Regulation pathopysiologischer und pathobiochemischer Prozesse chronisch-entzündlicher Erkrankungen maßgeblich beteiligt. In der vorliegenden Arbeit wurde diese Rolle durch Untersuchung des Expressionsprofils peptiderger Mediatoren und ihrer Rezeptoren unter normalen Bedingungen charakterisiert und auf dieser Grundlage Veränderungen des Mediatorstoffwechsels bei entzündlichen Erkrankungen erfasst. Aufgrund der geringen Kenntnisse bezüglich der Rolle anti-inflammatorischer Mediatoren wurde dabei insbesondere die Expression und Genregulation des Mediators VIP und seiner Rezeptoren untersucht. Dabei wurden molekularbiologische Methoden verwandt, um definierte Rezeptoren für VIP und verwandte Mediatoren in den Atemwegen und der Haut zu identifizieren. Im Anschluss daran wurde anhand verschiedener entzündlicher Erkrankungen der oberen Atemwege nachgewiesen, dass sich das peptiderge Mediatorprofil krankheitsspezifisch ändert und diese Subgruppen-spezifischen Änderungen nicht als ein universelles Epiphänomen der Entzündungsreaktion zu sehen sind. Ebenso konnte die Veränderung der Genexpression von Rezeptoren für peptiderge Mediatoren untersucht werden, wobei am Beispiel der Hypoxie die Induktion eines in den Atemwegen exprimierten Rezeptors nachgewiesen wurde. Am Beispiel der atopischen Dermatitis konnte darüber hinaus bewiesen werden, dass die Expression von VIP-Rezeptoren im Rahmen einer allergischen Erkrankung vermindert sein kann. Letztlich wurden ebenfalls mit VIP interferierende Transduktionsmechanismen untersucht, wobei die genauen Interaktionen peptiderger Mediatoren mit diesen intrazellulären Molekülen im Rahmen entzündlicher Erkrankungen noch aufzuschlüsseln sind. Die Ergebnisse der vorliegenden kumulativen Arbeit weisen in ihrer Gesamtheit auf eine wesentliche Bedeutung neurogener Mediatoren für pathophysiologische Mechanismen allergisch-entzündlicher Erkrankungen der Atemwege und Haut hin und lassen zukünftige therapeutische Ansätze auf Basis neuro-immunmodulierender Mechanismen sinnvoll erscheinen. / Peptidergic mediators participate next to their physiological role for numerous aspects of systemic and local homeostasis also in the regulation of pathophysiological and pathobiochemical processes in chronic inflammatory diseases. In the present study this role was investigated by assessing the expression profiles of peptidergic mediators and their receptors under physiological conditions. Basing on these findings differences of the mediator expression in inflammatory diseases were examined. Due to the relatively little knowledge on the role of potentially anti-inflammatory mediators the expression and gene regulation of the mediator VIP und its receptors were analysed. In this respect molecular techniques were used to assess distinct receptors for VIP and related mediators in the airways and skin. IN a next Step inflammatory diseases of the upper respiratory tract were examined and it was shown that the peptidergic mediators profile changes in relation to the disease entity and that this disease subtype-specific change is not a universal epiphenomenon of the ongoing inflammation. Also, alterations in the gene expression of peptidergic mediator receptors were analysed. Using hypoxia as an example the gene induction of airway-expressed receptors was demonstrated in relation to this stimulus. In further studies involving atopic dermatitis tissues a down-regulation of VIP receptor expression was demonstrated for allergic inflammatory conditions. In a last step VIP interfering signal transduction mechanisms were examined and future studies need to be carried out to fully assess the regulation of these interactions in relation to chronic inflammatory processes. The present results demonstrate an important role of neurogenic mediators in the pathophysiology of allergic inflammatory diseases of the airways and the skin and point to a potential use of neuro-immunomodulation in the future therapy of these diseases.
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Estudo dos mecanismos induzidos pelo treinamento físico aeróbico ao longo do tempo na inflamação pulmonar e no remodelamento brônquico em um modelo murino de asma / Study of the mechanisms induced by aerobic training over time in pulmonary inflammation and bronchial remodeling in an asthma murine model

Silva, Ronaldo Aparecido da 09 August 2013 (has links)
O treinamento aeróbico (TA) traz benefícios para os asmáticos, porém os mecanismos antiinflamatórios não são conhecidos. Estudos experimentais de asma têm mostrado que o TA reduz a inflamação pulmonar alérgica crônica (IPAC) e a reposta Th2, no entanto, nenhum estudo explicou quando os efeitos protetores são iniciados e qual é a principal via anti-inflamatória desencadeada. Objetivo: Avaliar o efeito do TA ao longo do tempo em um modelo murino de asma visando identificar quando são iniciados os efeitos anti-inflamatórios e a reversão do remodelamento brônquico (RB). Métodos: BALB/c (160 animais) foram divididos em 4 grupos: Controle (CT): não induzidos à IPAC e não treinados; Treinamento Aeróbico (TA): não induzidos à IPAC e treinados; OVA: induzidos à IPAC e não treinados; OVA+TA: induzidos à IPAC e treinados. Em seguida foram criados outros subgrupos 1, 3, 7, 15 e 30 dias de TA, ou seja, cada grupo foi repetidos 5 vezes para investigação do efeito do TA ao longo do tempo. Os grupos OVA foram sensibilizados com i.p. (OVA+HidroxAlum), após foram induzidos à IPAC com aerosol de OVA (1-3%) iniciado no dia 21 (3 x semana; 30 min./sessão). A adaptação ao TA foi realizada entre os dias 21 a 23, no dia 25 foi realizado o teste físico, no dia 28 o TA foi iniciado (50% intensidade, frequência 5 x, por 4 semanas). Vinte quatro horas da ultima sessão de TA (1, 3, 7, 15 e 30 dias) os animas foram anestesiados, eutanizados e coletados o lavado broncoalveolar (LBA) (contagem celular total e diferencial), sangue para quantificação das imunoglobulinas (IgE e IgG1) por técnica de reação de anafilaxia cutânea passiva (PCA), o tecido pulmonar para avaliação dos mediadores: IL-4, IL-5, eotaxina, RANTES, ICAM-1, VCAM-1, TGF-b, VEGF, Osteopontina (OPN), NF-kB, FOXP3, receptor de glicocorticóide (RG) e anti-inflamatórias IL-10 e IL-1ra (imunohistoquímica e quantificação por morfometria) e foi coletado também o músculo quadríceps para avaliação da produção das miocinas (IL-10, IL-1ra e IL-6) (imunohistoquímica e quantificado por análise de imagem). O RB (músculo liso, epitélio, deposições das fibras de colágeno e elástica e produção de muco) também foi avaliado por análise de imagem. Resultados: Não foi observada produção das miocinas (p>0,05). Os níveis de IgE, IgG1, migração celular, produção dos mediadores inflamatórios e o RB foram aumentados nos grupos OVA (p<0,05), que ainda mostraram redução da produção do RG (p<0,05). O TA aumentou o RG no músculo liso das vias aéreas, as produções de IL-10 e IL- 1ra aumentaram a partir do 7º dia por células peribrônquicas, ao mesmo tempo que foram reduzidos o NF-kB, IL-4, IL-5, eotaxina, RANTES, ICAM-1, VCAM-1, VEGF, eosinófilos no LBA e foram revertidos o espessamento do músculo liso, do epitélio e as deposições de fibras de colágeno (p<0,05). Curiosamente, a diminuição de TFG-b ocorreu após o 3º dia, enquanto OPN, elástica e muco ocorreram após 15 dias de TA, enquanto IgE, IgG1 e neutrófilos apenas foram reduzidas ao final de 30 dias (p<0,05). Conclusão: A partir do 3º dia do TA foi iniciado o mecanismo anti-inflamatório pelo aumento do RG no músculo liso das vias aéreas, seguido pelo aumento de IL-10 e IL-1ra e pela redução de NF-kB a partir do 7º dia do TA, efeitos que reverteram a inflamação alérgica crônica e o RB / The aerobic training (AT) promotes benefits for asthmatics, but the anti-inflammatory mechanisms are not known. Experimental studies of asthma have shown that AT reduces the pulmonary allergic chronic inflammation (PACI) and response Th2, however no study has ever explained when the protective effects are initiated and which is the main anti-inflammatory pathway triggered. Aim: To evaluate the effect of AT over time in a murine model of asthma to identify when the anti-inflammatory effects is started and reverse bronchial remodeling (BR). Methods: BALB/c (160 mice) were divided into 4 groups: Control (CT): not induced to PACI and untrained; Aerobic Training (TA): not induced to PACI and trained; OVA: induced to PACI and untrained; OVA + TA: induced to PACI and trained. After that were created others subgroups 1, 3, 7, 15 and 30 days AT, that is, each group was repeated 5 times to investigate the effect of AT over time. The OVA groups were sensitized with i.p. OVA (OVA+AlumHidrox), and then the mice were induced after the PACI with aerosol of OVA (1-3%) started on the 21st day (3 x week, 30 min./Session). Adaptation to TA was held between 21-23, on the 25th day the physical test was performed, and on day 28 AT was begun (50% intensity, frequency x 5 for 4 weeks). Twenty four hours of the after last session of AT (1, 3, 7, 15 and 30 days) the mice were anesthetized, euthanized and the bronchoalveolar lavage fluid was collected (BALF) (Total and differential cell count) and blood was used to quantify immunoglobulins (IgE and IgG1) by passive cutaneous anaphylaxis reaction (PCA) technique, the pulmonary tissue was removed and used to evaluate the mediators IL-4, IL-5, eotaxin, RANTES, ICAM-1, VCAM-1, TGF-b, VEGF, osteopontin (OPN), NF-kB, FOXP3, glucocorticoid receptor (GR), and antiinflammatory IL-10 and IL-1ra (immunohistochemistry and quantified by morphometry), was also the quadriceps muscle to assess the expression of myokines (IL-10, IL-1ra and IL-6) (by immunohistochemistry and image analyses). The BR (smooth muscle, epithelium, collagen and elastic fibers deposition, and mucus production) was also evaluated by image analysis. Results: It was not observed any production of myokines (p>0.05). The levels of IgE and IgG1, cell migration, production of inflammatory mediators, and the BR were increased in the OVA groups (p<0.05); that still showed a decreased production of the GR (p<0.05). The AT promoted an increase of GR in the airway smooth muscle from the 3rd day, the production of IL-10 and IL- 1ra were increased from day 7 for cells peribronchial, while NF-kB, IL-4, IL-5, eotaxin, RANTES, ICAM-1, VCAM-1, VEGF, eosinophil counting in BALF were reduced, and reversed the smooth muscle thickening, epithelium and deposition of collagen fibers too (p<0.05). Interestingly, the decreasing of TGF-b occurred in the 3rd day, and OPN, elastic fibers, mucus occurred after 15 days of AT, while IgE and IgG1, and neutrophils were reduced only after 30 days (p<0.05). Conclusion: The anti-inflammatory mechanism by increasing the GR on the smooth muscle of the airways was initiated from the 3rd day of the AT, followed by an increase of IL-10 and IL-1ra and a reduction of NF-kB from the 7th day of the AT, reversed the effects of chronic allergic inflammation and bronchial remodeling

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