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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.
301

Effects of sampling methodologies on Mycoplasma gallisepticum tissue populations in commercial layer pullets

Kattupparayil Sasidharan, Sethulakshmi 12 May 2023 (has links) (PDF)
Mycoplasma gallisepticum (MG) can cause chronic respiratory disease in chickens and infectious sinusitis in turkeys. Impacts of MG infections can include increased morbidity and mortality, decreased egg production, hatchability and feed efficiency. Biosecurity and bio-surveillance remain the primary means of deterrence as the current means of control are not wholly effective. Further applications towards the characterization of MG-related disease control requires proper understanding of the characteristics of MG infections with accurate and efficient quantification of in vivo MG populations. To this end, study was conducted to determine the in vivo MG populations in infected pullets and to determine impact of sampling schedule. The role of sampling in 3 distinct anatomical sites, and their associated MG populations were also compared. Results confirmed that sampling events did not affect MG populations and as a possible confounding factor, sampling frequency could be avoided for the future development of novel means of MG control.
302

In ovo vaccination of layer chickens with 6/85 and ts-11 vaccine strains of mycoplasma gallisepticum

Alqhtani, Abdulmohsen 25 November 2020 (has links)
Mycoplasma gallisepticum (MG) is the organism that causes avian respiratory mycoplasmosis, leading to chronic respiratory disease in chickens and infectious sinusitis in turkeys (Stipkovits and Kempf, 1996; Levisohn and Kleven, 2000). It is also responsible for reductions in egg production and other economic losses in the poultry industry (Stipkovits and Kempf, 1996; Levisohn and Kleven, 2000). Commercially, layer chickens are vaccinated against MG in the pullet phase before lay. In this dissertation, the potential application of in ovo vaccination in layer embryos for the subsequent early protection of pullets against field-strain MG infections was investigated. The use of different sites of injection [air cell (AC) or amnion (AM)] and various dosages of live attenuated 6/85 (6/85MG) and ts-11 (ts-11MG) vaccine strains of MG delivered in ovo at 18 days of incubation were evaluated. Vaccine dosages of ts-11MG up to 7.25 x 105 CFU did not have negative effects on the hatch and posthatch results. However, only the 7.25 x 105 CFU dosage had a negative effect on overall BWG. The ts-11MG was not transmitted from vaccinated to sentinel birds at both the hatch and posthatch periods, and no subsequent MG DNA or serology responses were detected in response to the vaccine. Administration of the 6/85MG vaccine at dosages up to 1.73 x 103 CFU did not negatively affect hatchability or other posthatch variables. Antibody production against 6/85MG through d 42 posthatch with no associated hatch or posthatch mortalities were likewise observed. The high dose of 6/85MG (1.73 x 104 CFU) resulted in a greater than 15 % mortality at hatch and a greater than 40 % mortality during the first 2 wk posthatch. Trachea and bronchi lesion scores in the pullets were significantly increased when they were challenged at d 28 of age with RMG. However, birds that were in ovo-vaccinated with 6/85MGV exhibited no significant microscopic lesions due to the RMG challenge. The 1.66 x 103 CFU dosage of 6/85MGV is proposed to offer the best protection in layer pullets against field-strain MG infections.
303

Physiological Factors Associated With The Alteration Of Reproductive Performance Of Commercial Egg Laying Chickens Infected With F-Strain Mycoplasma Gallisepticum

Burnham, Matthew Rex 11 May 2002 (has links)
The F-strain of Mycoplasma gallisepticum (FMG) is commonly used in vaccination programs to displace infections by more virulent natural or wild type Mycoplasma gallisepticum strains. However, a better understanding of the mechanisms responsible for altered egg production (EP) and egg quality in commercial layers infected with FMG is important, as these alterations can cause economic loss to the United States layer industry. This study was designed to examine potential mechanism(s) responsible for alterations in EP and egg quality by FMG-inoculation. The effects of FMG on production parameters and physiological characteristics of commercial laying hens were evaluated. In isolation units, 12 wk FMG inoculation delayed onset of lay approximately one wk, decreased overall EP, and decreased EP 34 wk post-inoculation. A 12 wk FMG inoculation also resulted in a higher incidence of fatty liver hemorrhagic syndrome, ovarian follicular regression, and decreased isthmal and vaginal proportions of the reproductive tract. Ovarian regression may be related to retarded production (liver), transport (blood), and/or uptake (ovary) of yolk particles. Changes in blood characteristics (i.e. lipid composition) with FMG colonization of the liver may become manifest through changes in egg constituents. As evidenced through changes in the relative weights of various reproductive organs, colonization of these organs by FMG, in addition to the liver, may also be a cause of the effects observed on EP. Increases in hematocrit, serum triglycerides, and plasma protein between 8 and 10 wk post FMG-inoculation, suggest that the initial weeks of EP are stressful. Post-peak decreases in these same variables suggest a more chronic inhibition on lipid and protein synthesis in the liver. Decreased blood lipid concentration may be directly responsible for the reductions in yolk lipid, cholesterol, and fatty acid deposition in 12 wk FMG-inoculated hens. Dual adverse effects in the caged layer facility on feed conversion and egg mass were realized in 22 wk FMG-inoculated birds. In contrast, a 12 wk FMG inoculation delayed onset of lay without a loss in total EP or egg mass. Therefore, inoculation with FMG at 12 wk is more practical and cost effective. Higher degrees of physiological stress experienced by hens in a caged layer facility may exacerbate the effects of FMG inoculation seen in the isolation units. These data demonstrate that alterations in performance and egg characteristics of commercial layers inoculated with FMG at either 12 or 22 wk of age and housed in either isolation units or caged layer facilities are related to mutual functional disturbances in the blood, liver, ovary, and oviduct without concomitant intestinal changes.
304

Studies on the transmission of the poultry disease, infectious synovitis, by using direct contact and insect vector methods

Peterson, Robert Victor 03 October 2008 (has links)
The possibilities of transmission of infectious synovitis were explored. Two types of tests, using mosquitoes as vectors, were employed. One type involved the feedings of mosquitoes on previously inoculated birds, then after a period of from zero to ninety-six hours refeeding the mosquitoes on assay birds. The second type of insect test comprised the feeding of mosquitoes on inoculated birds, then macerating and inoculating them into check birds at intervals of one to twenty-one days following feeding. Other experiments were conducted in which uninoculated birds were brought into close contact with inoculated chickens and their excrement. The observation of all tests indicated the absence of transmission of an infective titer of the infectious synovitis agent. These conclusions are drawn from tests using Aedes aegypti (Linn.) and Culex fatigans Wied., with methods and materials described. / Master of Science
305

Potential Downstream Immunological Effects of Evolved Disease Tolerance in House Finches

Rowley, Allison Annette 06 July 2020 (has links)
Emerging infectious diseases can exert strong selection on hosts to evolve resistance or tolerance to infection. However, it remains unknown whether the evolution of specific defense strategies against a novel pathogen influences host immune phenotypes more broadly, potentially affecting their ability to respond to other pathogens. In 1994 the bacterial pathogen, Mycoplasma gallisepticum (MG) jumped from poultry into house finches, causing severe conjunctivitis and reducing host survival. MG then spread across the continental United States, exerting strong selection on host populations and creating geographic variation in the degree of population co-evolutionary history with the pathogen. Prior work found that populations of house finches with longer histories of MG endemism have evolved tolerance and resistance to MG, and this evolution is associated with several immunological differences including reductions in pro-inflammatory immune responses. However, it remains unknown whether these immunological changes are limited to MG-specific defenses or whether broader immune responses differ between populations with distinct coevolutionary histories with MG. To examine possible effects of the evolution of host responses to MG, we used five immune assays to challenge house finches from four populations, ranging from no history of MG endemism to 20+ years of MG endemism. When challenged with phytohemagglutinin (PHA), populations differed significantly in the strength of wing web swelling, with populations with longer MG exposure (and thus the highest MG tolerance) on average exhibiting the weakest swelling response when mass differences were controlled for. However, detected population differences in wing web swelling were small, and population differences were absent for responses to four other immune assays that spanned components of the innate and adaptive immune system. Future work should examine whether the local inflammation that underlies swelling responses to PHA shares common immunological mechanisms with local inflammatory responses to MG, which may explain why populations with evolved tolerance to MG show slightly lower swelling responses in response to PHA. Overall, these results suggest that the evolution of MG tolerance may have minor downstream consequences for responses to certain antigens, with the potential to influence a host's ability to respond to novel pathogen challenges, but most components of the host immune system appear largely unaffected. / Master of Science / Emerging infectious diseases can have devasting effects on new host species. To reduce the cost of these pathogens, host species can evolve ways to eliminate infection (resistance) or reduce damage during infection (tolerance), which is often caused by the host's immune system itself. As populations evolve these disease strategies, it is likely that other aspects of the immune system will also be affected, potentially compromising the ability of hosts to respond to pathogens other than the ones they evolved defenses against. We examined what sort of trade-offs might arise as house finches evolved resistance and tolerance to a new deadly pathogen, Mycoplasma gallisepticum (MG). House finch populations in the mid-Atlantic were first exposed to the disease in 1994, and as the disease spread across the continental United States, different populations have been exposed for different periods of time. This created a gradient in whether certain populations have had long enough time with MG to evolve disease strategies. Populations that have been exposed to MG for longer appear to have evolved both resistance and tolerance, and tolerant populations show lower levels of inflammatory immune markers that can be associated with self-damage. Using house finches from four different populations (ranging from 25 years of exposure history to zero years of MG exposure history), we tested a variety of immune system components to examine what areas of the immune system might have been broadly affected by the evolution of resistance and tolerance. We hypothesized that birds from populations with evolved MG tolerance would also have a reduced inflammation response when stimulated with substances that mimic infection by something other than MG. Only one assay supported this hypothesis. Birds from populations that had been exposed to MG for a longer period of time (and thus had evolved MG tolerance) had a reduced swelling response following injection with a plant protein called phytohemagglutinin. However, there were no population differences observed with the other four assays, suggesting that evolving defenses against MG did not result in widespread immunological effects. This suggests that the evolution of host defenses against an emerging pathogen may not compromise that host's ability to respond effectively to other types of pathogens that they encounter in nature.
306

Effects of Bird Feeder Density on the Behavior and Ecology of a Feeder-Dependent Songbird: Patterns and Implications for Disease Transmission

Aberle, Matthew A. 18 September 2018 (has links)
Anthropogenic resource provisioning of wildlife has increasingly been hypothesized to alter pathogen spread. Although bird feeding is the most widespread form of intentional wildlife provisioning, we know relatively little about how the degree of anthropogenic feeding at a site impacts wild birds in ways relevant to disease transmission. We manipulated the density of bird feeders (low versus high) available at otherwise similar sites and tracked the local abundance, body condition (scaled-mass index), feeding behavior, and movement across the landscape in wild house finches (Haemorhous mexicanus), a feeder-dependent species subject to outbreaks of a contagious pathogen commonly spread at feeders. The local abundance of house finches was significantly higher at sites with high feeder density but, surprisingly, finches at high-density feeder sites had poorer body condition than those at low-density sites. Behaviorally, birds at high-density feeder sites had longer average feeding bouts and spent more time per day on feeders than birds at low-density feeder sites. Further, birds first recorded at low-density feeder sites were more likely to move to a neighboring high-density feeder site than vice versa. Overall, because local abundance and time spent on feeders have been linked with the risk of disease outbreaks in this species, effects of bird feeder density on both traits may, in turn, influence disease dynamics in house finches. Our results suggest that heterogeneity in the density of bird feeders can have diverse effects on wild birds, with potential consequences for disease transmission. / Master of Science / Feeding wildlife has increasingly been thought to change the spread of disease. Although bird feeding is the most widespread form of intentional wildlife feeding, we know relatively little about how much human feeding impacts wild birds in ways that affect disease transmission. We changed the density of bird feeders (low versus high) available at otherwise similar areas and tracked the local abundance, body condition, feeding behavior, and movement across the landscape in wild house finches (Haemorhous mexicanus), a feeder-dependent species subject to outbreaks of a infectious disease commonly spread at feeders. The local abundance of house finches was significantly higher at sites with high feeder density but, surprisingly, finches at high-density feeder sites had poorer body condition than those at low-density sites. Behaviorally, birds at high-density feeder sites had longer average bouts on feeders and spent more time per day on feeders than birds at low-density feeder sites. Further, birds first recorded at low-density feeder sites were more likely to move to a neighboring high-density feeder site than vice versa. Overall, because local abundance and time spent on feeders have been linked with the risk of disease outbreaks in this species, effects of bird feeder density on both traits may, in turn, increase disease spread in house finches. Our results suggest that variation in the density of bird feeders can have diverse effects on wild birds, with potential consequences for disease transmission.
307

Behavioral Heterogeneity and Disease Dynamics in House Finches (Haemorhous mexicanus)

Moyers, Sahnzi C. 16 June 2017 (has links)
Infectious disease is a ubiquitous aspect of life on earth; however, parasites and pathogens are not distributed equally among individual hosts. Due to its ability to shape the way that individuals interact with other potential hosts and the environment, behavior is one of the most salient ways through which host biology varies in the context of disease. Variation in animal behavior can impact both transmission and the extent of a host's pathogen acquisition, and thus can have important consequences for infectious disease dynamics. Additionally, in this world of rapid urbanization where landscapes and wildlife resources are being altered, it is important to understand the ways in which human activity impact wildlife behavior, and in turn, disease dynamics. Here, we used both observational and experimental studies in field and laboratory settings to investigate the relationships among host behavior and physiology, anthropogenic food sources, and disease transmission in a natural host-pathogen system. First, we examined the relationship between house finch (Haemorhous mexicanus) stress physiology, exploratory behaviors, and social behaviors in the wild. We provided evidence that more exploratory house finches interact with more individuals in the wild, and have higher baseline concentrations of circulating stress hormones. Next, we found evidence that the amount of time spent on bird feeders drives both the acquisition and transmission of the bacterial pathogen Mycoplasma gallisepticum (Mg), indicating that variation in host foraging behavior has important transmission consequences in this system. Lastly, we found that the density of bird feeders available to house finches predicts the extent of Mg transmission in captivity. Taken together, these results highlight the important role that behavioral heterogeneity can play in the acquisition and spread of pathogens, as well as the potential impacts of human behavior on wildlife disease dynamics. Future work should seek to identify specific physiological mechanisms driving Mg acquisition and transmission as they relate to variation in host behavior, and the ways in which bird feeders impact disease-relevant behaviors in the wild. / Ph. D. / Infectious disease impacts almost every living creature on earth; however, some individuals are more likely to become sick and spread disease than others. Animal behavior can strongly influence disease dynamics due to its ability to shape the way that individuals interact with one another and the environment. Behavior can impact an individual’s likelihood of both acquiring and spreading disease, and thus can have important consequences for disease outbreaks. Additionally, as urban areas are expanding, it is important to understand the ways in which human activity impact wildlife behavior, and in turn, disease dynamics. Through both laboratory and field studies, we investigate the relationships among host behavior and physiology, human-related food sources, and disease transmission in a natural wildlife disease system. First, we examined the relationships between stress hormones, exploratory behaviors, and social behaviors of house finches, a common songbird. We provided evidence that more exploratory house finches interact with more individuals in the wild, and have higher concentrations of stress hormones. Next, we found evidence that the amount of time that house finches spend on bird feeders drives both the likelihood of acquiring and spreading conjunctivitis (=pink eye). This means that certain individuals are more likely to get sick and pass the disease on to others than other individuals are. Lastly, we found that when the density of bird feeders available to house finches is high, we see more disease transmission. Taken together, these 5 results highlight the important role that variation in behavior can play in acquiring and spreading disease, as well as the potential impacts of human behavior on wildlife health.
308

Expressão aumentada dos antígenos de MMP-9 PPAR, Chlamydophila pneumoniae e Mycoplasma pneumoniae em fragmentos ateroscleróticos de aorta com aneurisma / Increased expression of MMP-9, PPAR a and Chlamydophila pneumoniae e Mycoplasma pneumoniae antigens in atherosclerostic aortic fragments with aneurysms

Roggerio, Alessandra 12 September 2008 (has links)
Introdução: Aneurisma de aorta é considerado uma doença inflamatória crônica, mas ainda é controverso se está relacionado a aterosclerose aos agentes infecciosos. Antígenos de Chlamydophila pneumoniae (CP) e Mycoplasma pneumoniae (MP) foram encontrados em grande quantidade nas placas instáveis que usualmente estão associadas a remodelamento positivo e inflamação do vaso. Metaloproteinase da matriz 9 (MMP-9) está implicada na fragilidade da parede vascular e na formação dos aneurismas. Os efeitos imunomodulatórios dos receptores ativados por proliferador de peroxissomo (PPARs) têm sido relacionados à aterosclerose. Objetivos: Comparar lesões ateroscleróticas graves com e sem aneurisma do ponto de vista inflamatório e infeccioso, analisando antígenos de MP e CP e expressão de MMP-9, TIMP-1 e PPARs. Métodos: No presente estudo quantificamos, através da técnica de imunoistoquímica, antígenos de MMP- 9, TIMP-1, PPARs a e , e dos agentes infecciosos CP e MP em fragmentos de aorta ateroscleróticos com aneurisma (n=14) e sem aneurisma (n=14). Resultados: A adventícia e o tecido adiposo periadventicial (TAP) dos aneurismas apresentaram intensa inflamação. Expressão de MMP-9 esteve aumentada no TAP e agentes infecciosos, TIMP-1 e PPAR a estiveram aumentados na adventícia e no TAP, sem diferença em relação a expressão de PPAR . Colágeno, TIMP-1 e PPARs estiveram positivamente correlacionados no grupo com aterosclerose, mas não no grupo com aneurisma. Conclusão: Nossos achados sugerem que aneurisma de aorta é uma complicação das lesões ateroscleróticas. Quantidade aumentada de Chlamydophila pneumoniae e Mycoplasma pneumoniae na adventícia e PAT sem correlação da resposta de TIMP-1 e PPARs são achados que estão associados com a presença de aneurisma nos segmentos de aorta ateroscleróticos / Introduction: Aortic aneurysm is considered a chronic inflammatory disease, but remains a controversial matter if it is related to atherosclerosis and infectious agents. Chlamydophila pneumoniae (CP) and Mycoplasma pneumoniae (MP) antigens were found in higher amount in unstable plaques that are usually associated to positive remodeling and vessel inflammation. Matrix metalloproteinase 9 (MMP-9) has been implicated in vascular wall fragility and aneurysm development. The immunemodulator effects of peroxisome proliferators - activated receptor (PPARs) have been related to atherosclerosis. Objectives: To compare severe atherosclerotic lesions with and without aneurysms by inflammatory and infectious point of view, analyzing MP and CP, MMP-9, TIMP-1 and PPARs antigens. Methods: In the present study we quantified, using immunohistochemistry technique, MMP-9, TIMP-1, PPAR a and and infectious agents CP and MP antigens in aortic atherosclerotic fragments with aneurysms. (n=14) and without aneurysms (n=14). Results: Adventitia and periadventitial adipose tissue (PAT) from aneurysms showed intense inflammation. MMP-9 expression has increased in PAT and the infectious agents, TIMP-1 and PPAR a were increased in adventitia and PAT in aneurysmatic group, without difference related to PPAR expression. Collagen, TIMP-1 and PPARs were positively correlated in atherosclerotic group, but it was not observed in aneurysmatic group. Conclusion: Our data have suggested that aortic aneurysm is a complication of aortic atherosclerotic lesions. Increased amount of Chlamydophila pneumoniae and Mycoplasma pneumoniae in the adventitia and PAT without a correlated TIMP-1 and PPARs response are findings that were associated with the presence of aneurysm in atherosclerotic aortic segments
309

Estudo biomolecular de produtos de Chlamydophila pneumoniae, Mycoplasma pneumoniae e Borrelia burgdorferi na etiopatogenia da degeneração mixomatosa da valva mitral / A biomolecular study on Chlamydophila pneumoniae, Mycoplasma pneumoniae and Borrelia burgdorferi products in myxoid mitral valve degeneration etiopathogenesis

Tiveron, Marcos Gradim 11 December 2015 (has links)
Introdução e Objetivo: A doença mixomatosa da valva mitral leva ao comprometimento de sua matriz devido à alteração em sua composição tecidual provocada pelo desequilíbrio na quantidade de ácidos mucopolissacarídeos ou glicosaminoglicanos. Sua etiologia ainda não está totalmente esclarecida, podendo ocorrer em formas familiares com transmissão autossômica dominante de penetrância variável, que pode ser dependente do tempo ou de prováveis fatores ambientais, situações em que a interação de agentes infecciosos necessita de maiores esclarecimentos. O objetivo deste estudo é a análise dos produtos dos patógenos da Chlamydophila pneumoniae, Mycoplasma pneumoniae e Borrelia burgdorferi em segmentos de cúspide retirados da valva mitral com degeneração mixomatosa, comparada ao grupo controle e a relação dos produtos bacterianos com aumento de marcadores inflamatórios (CD20, CD48, CD68) e de metaloproteinase (MMP9) na etiopatogenia da degeneração mixomatosa da valva mitral. Método: Estudo observacional, analítico, tipo caso-controle, que analisou 2 grupos contendo 20 pacientes cada e divididos em grupo 1, composto por fragmentos de tecido valvar mitral com diagnóstico de degeneração mixomatosa extraídos em procedimentos de troca ou plásticas valvares mitrais; e grupo 2, formado por segmentos de valvas mitrais sem valvopatia retirados no serviço de verificação de óbito. Foram realizadas colorações de hematoxilina e eosina e Movat para diagnóstico histológico da degeneração mixomatosa e técnica de imunohistoquímica para detecção de antígenos da Borrelia burgdorferi, Mycoplasma pneumoniae, mediadores inflamatórios (CD20, CD45, CD68) e marcadores de metaloproteinase (MMP9). A presença de antígenos da Chlamydophila pneumonia e foi pesquisada pela técnica de hibridização in situ. A análise quantitativa dos aspectos microscópicos foi realizada com o analisador de imagens Aperio. A pesquisa de elementos bacterianos foi feita através de microscopia eletrônica de transmissão. Resultados: No grupo 1, 14 (70%) pacientes são do gênero masculino e 6 (30%) do gênero feminino. A idade média é de 67,4 anos (51 a 79 anos, dp = 9,2). No grupo 2, 11 (55%) pacientes são do gênero masculino e 9 (45%) do gênero feminino. A idade média é de 67,6 anos (42 a 84 anos, dp= 12,0). Na análise da porcentagem de degeneração mixomatosa pela coloração Movat, houve diferença com significância estatística entre os grupos DM (G1), com média de 54,6 % ± 23,7 e grupo controle (G2) com média de 35,5 % ± 22,5 com valor de p = 0,013. Houve um maior número de células CD20 positivas/mm2 no grupo com DM com mediana igual a 17,8 (6,7 - 27,9) x 4,6 (3,6 - 9,8) com p = 0,007 para a área 1. Houve maior número de células CD45 positivas/mm2 no grupo com DM com mediana igual a 17,3 (3,4 - 92,5) x 2,8 (1,4 - 10,1) com p = 0,008 para a área 1. Houve maior número de células CD68 positivas/mm2 no grupo controle (G2), porém sem significância estatística com mediana igual a 38,7 (26,6 - 81,8) x 70 (42,7 - 120,4) com p = 0,098 para a área 1. Em relação à presença de antígenos de Mycoplasma pneumoniae, houve uma maior área (?m2) de antígenos detectados no grupo 1, quando comparadas com o grupo 2 com diferença estatisticamente significante para as duas áreas. Na área 1, mediana de 180.993 (24.856 - 387.477) x 7.970 (2.736 - 15.992) com p < 0,001 e na área 2, mediana igual a 105.968 (2.503 - 416.585) x 7.190 (3.314 - 17.833) com p = 0,02 A análise da presença de antígenos de Chlamydophila pneumoniae demonstrou que em ambas as áreas, houve uma maior área (?m2) de antígenos detectados no grupo de valvas com degeneração mixomatosa, quando comparadas com o grupo controle, porém sem diferença estatística com mediana para o G1 de 9.905 (4.716 - 16.912) x 5.864 (2.382 - 8.692) com p = 0,2 e para o G2, mediana de 3.199 (1.791 - 10.746) x 2.536 (683 - 6.125) com p = 0,3. Em relação à presença de antígenos de Borrelia burgdorferi, houve uma maior área (um2) de antígenos detectados no grupo 2 em relação ao grupo 1, em ambas as áreas. Na área 1, mediana de 7.596 (3.203 - 13.519) x 10.584 (7.223 - 15.974) com p = 0,14 e na área 2, mediana igual a 5.991 (3.009 - 8.475) x 8.403 (1.626 - 27.887) com p = 0,47. Em relação à presença da metaloproteinase MMP9, observamos maior área (um2) de antígeno marcado de MMP9 no grupo com degeneração mixomatosa tanto na área 1 quanto na área 2, com diferença estatística significante. Na área 1, mediana de 503.894 (202.428 - 938.072) x 269.244 (111.953 - 354.022) com p = 0,03. Na área 2, houve diferença estatística representada pela mediana de 389.844 (214.459 - 679.711) x 144.397 (29.894 - 247.453) com p < 0,001. No grupo DM houve correlação positiva entre Borrelia burgdorferi e porcentagem de DM com R = 0,52 e p = 0,018. Em relação às células inflamatórias, houve correlação positiva entre CD45 e Mycoplasma pneumoniae com R = 0,51 e p = 0,02. A presença de MMP9 se correlacionou positivamente com a presença de Mycoplasma pneumoniae com R = 0,45 e p = 0,04. Estas correlações estiveram ausentes no grupo controle. Conclusões: Houve associação de agentes infecciosos Mycoplasma pneumoniae e Borrelia burgdorferi na etiopatiopatogenia da degeneração mixomatosa da valva mitral. Na análise da relação dos produtos bacterianos com os marcadores inflamatórios e com a metaloproteinase, houve relação positiva entre o marcador inflamatório CD45 e a metaloproteinase (MMP9) apenas com a Mycoplasma pneumoniae, nas valvas com degeneração mixomatosa. O marcador inflamatório CD68 foi encontrado em maior número no grupo controle / Background: The myxomatous mitral valve disease leads to impairment due to changes in their tissue composition caused by the imbalance in the amount of acid mucopolysaccharides or glycosaminoglycans. Its etiology is not yet fully understood and may occur in familial forms of autosomal dominant trait with variable penetrance that can be time-dependent or probable environmental factors, where the interaction of infectious agents requires further elucidation. The purpose of this study is the analysis of the pathogens products of Chlamydophila pneumoniae, Mycoplasma pneumoniae and Borrelia burgdorferi in removed cusp segments of the mitral valve with myxoid degeneration, compared to the control group and the ratio of bacterial products with increased inflammatory markers (CD20, CD48, CD68) and metalloproteinase (MMP9) in the pathogenesis of myxomatous degeneration of the mitral valve. Method: Observational, analytical, case-control study which analyzed 2 groups of 20 patients each and divided in group 1, consisting of fragments of mitral valve tissue with diagnosis of myxomatous degeneration extracted in replacement procedures or mitral valve repair; group 2, formed by segments of mitral valves without valvolpaty clinial disease removed in the coroner service. Hematoxylin and eosin and Movat stains were done for histological diagnosis of myxoid degeneration and immunohistochemical technique for the detection of Borrelia burgdorferi, Mycoplasma pneumonia antigens, inflammatory mediators (CD20, CD45, CD68) and markers of metalloproteinase (MMP9). The presence of Chlamydophila pneumonia antigens was verified through an in situ hybridization technique. The quantitative analysis of the microscopic aspects was performed with the Aperio image analyzer. The research of bacterial elements was performed by a transmission electron microscopy. Results: In group 1, 14 (70%) patients were male and 6 (30%) were female. The mean age was (51 to 79 years, sd = 9.2). In group 2, 11 (55%) patients were male gender and 9 (45%) were female. The mean age was 67,6 years (42 to 84 years, sd= 12). In the analysis percentage of myxomatous tissue by Movat staining, there was a significant difference between the DM (G1) groups, with a media of 54.6 % ± 23,7 and control group (G2) with a media of 35.5 % ± 22.5 with p = 0.013. There was an increased number of CD20 cells/mm2 in myxomatous degeneration group (G1) with a median of 17.8 (6.7 - 27.9) x 4.6 (3.6 - 9.8) with p = 0.007 for the area 1. There was a higher number of CD45 cells/mm2 in myxomatous degeneration group (G1) with a median of 17.3 (3.4 - 92.5) x 2.8 (1.4 - 10.1) with p = 0.008 for the area 1. There was a higher number of CD68 cells/mm2 in control group (G2) without a statistically significant difference, with a median of 38.7 (26.6 - 81.8) x 70 (42.7 - 120.4) with p = 0,098 for the area 1. In quantifying Mycoplasma pneumoniae we observed a higher area (um2) antigen marked by, there was a higher amount of antigen detected in myxomatous degeneration group. In area 1, a median of 180,993 (24,856 - 387,477) x 7,970 (2,736 - 15,992) with p < 0.001 and in area 2, a median of 105,968 (2,503 - 416,585) x 7,190 (3,314 - 17,833) with p = 0.02. The analysis of the presence of Chlamydophila pneumoniae antigens showed that in both area, there was a larger area (?m2) antigens detected in the group of valves with MD when compared with the control group, but without significant differences with median for the G1 of 9,905 (4,716 - 16,912) x 5,864 (2,382 - 8,692), with p = 0.2 and the G2, median 3,199 (1,791 - 10,746) x 2,536 (683 - 6,125) with p = 0.3. Regarding the presence of Borrelia burgdorferi antigens, there was a greater area (?m2) antigens detected in group 2 than in group 1, in both areas. In one area, median 7,596 (3,203 - 13,519) x 10,584 (7,223 - 15,974), with p = 0.14 and in area 2, a median of 5,991 (3,009 - 8,475) x 8,403 (1,626 - 27,887) with p = 0.47. Regarding the presence of metalloproteinase MMP9, we observed a higher area (um2) antigen marked by MMP9 in the group with MD both in area 1and area 2, with statistically significant difference. In area 1, median of 503,894 (202,428 - 938,072) x 269,244 (111,953 - 354,022), p = 0.03. In area 2, median 389,844 (214,459 - 679,711) x 144,397 (29,894 - 247,453) with p < 0.001. In the DM group there was a positive correlation between Borrelia burgdorferi and the percentage of MD with R = 0.52 and p = 0.018. Regarding inflammatory cells, there was a positive correlation between CD45 and Mycoplasma pneumoniae with R = 0.51 and p = 0.02. The presence of MMP9 was positively correlated with the presence of Mycoplasma pneumoniae with R = 0.45 and p = 0.04. These correlations were absent in the control group. Conclusions: There was an association of infectious agents Mycoplasma pneumoniae and Borrelia burgdorferi in etiopathogeny of myxoid degeneration of the mitral valve. In the analysis of the relationship of bacterial products with the inflammatory markers and the metalloproteinase, there was a positive relationship between the inflammatory marker CD45 and metalloproteinase (MMP9) only with Mycoplasma pneumoniae. The inflammatory marker CD68 was found in greater numbers in the control group
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Imunidade inata na asma fatal / Innate immunity in fatal asthma

Ferreira, Diogenes Seraphim 13 August 2010 (has links)
INTRODUÇÃO: A inflamação das vias aéreas na asma envolve respostas imunes inatas. Os receptores do tipo Toll (Toll-like receptors, TLRs) e a citocina linfopoetina do estroma tímico (thymic stromal lymphopoietin, TSLP) estão envolvidos na inflamação brônquica da asma, mas a expressão destas proteínas em vias aéreas grandes e pequenas de asmáticos ainda não foi investigada. Os objetivos deste estudo foram analisar a expressão protéica de TLR2, TLR3, TLR4 e TSLP em vias aéreas grandes e pequenas de asmáticos, comparar sua expressão entre asmáticos tabagistas e não tabagistas e investigar se a expressão dos TLRs está associada à infecção por Chlamydophila pneumoniae e Mycoplasma pneumoniae. MÉTODOS: Foram analisadas por método imuno-histoquímico e análise de imagens as expressões de TLR2, TLR3, TLR4 e TSLP em vias aéreas grandes e pequenas de 24 indivíduos falecidos por asma (13 não tabagistas e 11 tabagistas) e 9 controles não asmáticos. A análise das proteínas foi realizada em quatro regiões das vias aéreas: camadas epitelial, interna, muscular e externa. A presença de C. pneumoniae e M. pneumoniae no tecido pulmonar foi investigada por meio de reação em cadeia da polimerase em tempo real. RESULTADOS: Os indivíduos asmáticos apresentaram maior expressão de TLR2 nas camadas epitelial e externa de vias aéreas grandes e pequenas, e maior TLR2 na camada muscular de vias aéreas pequenas. Asmáticos tabagistas tiveram menor expressão de TLR2 nas camadas interna e externa de vias aéreas pequenas do que asmáticos não tabagistas. Indivíduos asmáticos tiveram maior expressão de TSLP na camada epitelial e externa de vias aéreas grandes, aumento de TLR3 na camada externa de vias aéreas grandes e aumento de TLR4 na camada externa de vias aéreas pequenas. O DNA de C. pneumoniae e M. pneumoniae não foi detectado em nenhum indivíduo asmático ou controle. CONCLUSÕES: Os receptores da imunidade inata TLR2, 3 e 4 e a citocina TSLP estão aumentados nas vias aéreas de pacientes falecidos por asma, e a expressão dos TLRs não está associada à presença de Chlamydophila pneumoniae e Mycoplasma pneumoniae nos pulmões. O tabagismo em asmáticos parece reduzir a expressão de TLR2 em vias aéreas pequenas. Estes resultados sugerem que os TLRs 2, 3 e 4 e a TSLP podem contribuir com a inflamação brônquica presente em exacerbações graves de asma e que as bactérias C. pneumoniae e M. pneumoniae não estão envolvidas em óbitos por asma / INTRODUCTION: Airway inflammation in asthma involves innate immune responses. Toll-like receptors (TLRs) and the cytokine thymic stromal lymphopoietin (TSLP) are involved in bronchial inflammation in asthma, but the expression of these proteins in large and small airways of asthmatics has not been investigated. The aims of this study were to analyze the protein expression of TLR2, TLR3, TLR4 and TSLP in large and small airways of asthmatics, to compare their expression in smoking and nonsmoking asthmatics and to investigate if TLR expression in associated with infection by Chlamydophila pneumoniae and Mycoplasma pneumoniae. METHODS: Using immunohistochemistry and image analysis, we investigated the expression of TLR2, TLR3, TLR4 and TSLP in large and small airways of 24 fatal asthma patients (13 nonsmokers and 11 smokers) and 9 nonasthmatic controls. The protein expression was analyzed in four regions of the airways: epithelial, internal, airway smooth muscle and outer layers. C. pneumoniae and M. pneumoniae presence in lung tissue was analyzed by real-time polymerase chain reaction. RESULTS: Fatal asthma patients had increased expression of TLR2 in the epithelial and outer layers of large and small airways, and also higher TLR2 in the muscle layer of small airways. Smoking asthmatics had lower TLR2 in the inner and outer layers of small airways than nonsmoking asthmatics. TSLP was increased in the epithelial and outer layers of large airways. Asthmatics also had greater TLR3 in the outer layer of large airways and greater TLR4 in the outer layer of small airways. C. pneumoniae and M. pneumoniae DNA was not detected in asthmatics or controls. CONCLUSIONS: Innate immunity receptors TLR2, 3 and 4 and innate cytokine TSLP are increased in the airways of fatal asthma patients, and TLRs expression is not associated with the presence of Mycoplasma pneumoniae and Chlamydophila pneumoniae in the lungs. Smoking may reduce TLR2 expression in the small airways of asthmatics. These results suggest that TLR2, 3, 4 and TSLP may contribute to the bronchial inflammation seen in severe exacerbations of asthma and that M. pneumoniae and C. pneumoniae are not involved in fatal asthma exacerbations

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