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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.
331

Associação entre concentração sérica de vitamina D e alterações da massa muscular esquelética em pacientes com doenças inflamatórias intestinais /

Gondo, Fernanda Futino. January 2015 (has links)
Orientador: Sérgio Alberto Rupp de Paiva / Coorientador: Lìgia Yukie Sassaki / Banca: Renata Maria Galvão de Campos Cintra / Banca: Erick Parado de Oliveira / Resumo: Introdução: Modificações na massa muscular esquelética e a deficiência de vitamina D têm sido relatadas frequentemente na literatura em pacientes com doenças inflamatórias intestinais (DII). Entretanto, a associação entre vitamina D e alterações musculares na DII são desconhecidas. O objetivo do presente estudo foi verificar se as modificações na massa muscular esquelética são explicadas pelo estado nutricional de vitamina D em pacientes com doenças inflamatórias intestinais. Métodos: Foi conduzido estudo observacional em que foram avaliados 73 pacientes ambulatoriais, com Doença de Crohn e Retocolite Ulcerativa da Faculdade de Medicina de Botucatu, Brasil, que tiveram diagnóstico confirmado da doença por meio dos parâmetros clínicos, endoscópicos e histológicos. A composição corporal total e segmentar foi estimada por absortiometria por raios-X de dupla energia. Para a definição de sarcopenia foram utilizados critérios do European Working Group on Sarcopenia in Older People. Amostras sanguíneas foram coletadas para avaliação das concentrações de hemoglobina, hematócrito, velocidade de hemossedimentação, proteína C-reativa, albumina e 25-hidroxivitamina D sérica (25(OH)D). Para avaliação da capacidade física foi realizado o teste de caminhada de 6 minutos, com base nas diretrizes estabelecidas pela American Thoracic Society (2002). A força isométrica de preensão manual dos indivíduos foi obtida da mão não dominante dos indivíduos por um dinamômetro hidráulico manual. O Questionário Internacional de Atividade Física foi utilizado para avaliar o nível de atividade física. O estado nutricional de vitamina D foi avaliado por meio de recordatório alimentar de 24horas e questionário de exposição solar. Todos os participantes foram questionados quanto ao consumo de bebidas alcoólicas e fumo. Os resultados foram expressos em média ± DP ou mediana e quartil 1 e quartil 3 ou... / Abstract: Background: Changes in skeletal muscle mass and vitamin D deficiency have been frequently reported in the literature in patients with inflammatory bowel disease. However, the association between vitamin D and muscle changes in patients with inflammatory bowel diaseases is unclear. This study aimed to verify if changes in skeletal muscle mass are explained by nutritional status of vitamin D in patients with inflammatory bowel diseases. Methods: This observational study assessed 73 outpatients with Crohn's Disease and Ulcerative Colitis from Botucatu Medical School, Brazil, who have confirmed the diagnosis of their disease trough the clinical, endoscopic and histological parameters. Whole body and regional body composition was obtained by dual-energy X-ray absorptiometry. Criteria of European Working Group on Sarcopenia in Older People were used to define sarcopenia. Peripheral blood samples were obtained for measurements of hemoglobin, hematocrit, erythrocyte sedimentation rate, C-reactive protein, albumin, and serum 25-hydroxyvitamin D (25(OH)D). The 6-minute walk test was performed for evaluation of physical capacity, based on the guidelines established by the American Thoracic Society (2002). Grip strength of the subject's non-dominant hand was assessed with a hydraulic hand dynamometer, which measures isometric grip force. The International Physical Activity Questionnaire was used to evaluate the physical activity. The nutritional status of vitamin D was assessed by 24hour dietary recall and sun exposure questionnaire. All participants were asked about their alcohol intake and smoking. Results were expressed as mean ± SD or median with quartile 1 and quartile 3 ranges or percentage. We used the Fisher exact test for the associations between categorical variables, the Student t-test or Mann-Whitney test for differences between patients with sarcopenia or not and Multiple Logistic Regression. We adopted a significance level of 5% ... / Mestre
332

Desenvolvimento e caracterização de nanopartículas com propriedades mucoadesivas baseadas em ácido hialurônico para liberação cólon específica de metotrexato /

Boni, Fernanda Isadora. January 2017 (has links)
Orientador: Maria Palmira Daflon Gremião / Coorientador: Beatriz Stringhetti Ferreira Cury / Banca: Leila Aparecida Chiavacci Favorin / Banca: Ruy Carlos Ruver Beck / Resumo: A nanotecnologia farmacêutica é uma relevante ferramenta tecnológica para o desenvolvimento de novos sistemas para a veiculação de fármacos, pois devido às suas dimensões reduzidas são capazes de circular por capilares que irrigam os tecidos, escapar da fagocitose por células do sistema imunológico e permear passivamente células e epitélios. Além disso, esses sistemas possibilitam a encapsulação de fármacos de baixa estabilidade, protegendo-os contra degradação prematura e/ou permitindo a modulação de suas propriedades físico-químicas, bem como a interação biológica na biointerface. O metotrexato (MTX) é um dos fármacos mais utilizados no tratamento de tumores sólidos e doenças inflamatórias intestinais, no entanto, por ser altamente citotóxico e não seletivo promove diversos efeitos colaterais. Sua eficácia terapêutica é comprometida devido à resistência adquirida pelas células tumorais e por sua baixa permeabilidade intestinal, principalmente por meio do mecanismo de efluxo da forma livre. Nesse trabalho, nanopartículas poliméricas (NPs) orais compostas por quitosana (QS), ácido hialurônico (AH) e ftalato de hidroxipropilmetilcelulose (HP), polímeros que possuem propriedades como solubilidade pH dependente, mucoadesividade e de funcionalização, foram desenvolvidas como plataforma tecnológica para a vetorização do MTX para o cólon, visando o tratamento local de patologias intestinais. As análises de peso molecular e coeficiente viral demostraram a adequação dos polímeros e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The pharmaceutical nanotechnology is a relevant technological tool for the development of new drug delivery systems, because of their small size they are able to circulate through capillaries that irrigate tissues, escape from phagocytosis by the immune system cells and passively permeate cells and epithelia. In addition, these systems enable the encapsulation of low stability drugs, protecting them against premature degradation and/or allowing the modulation of their physico-chemical properties, as well as the biological interaction in the biointerface. Methotrexate (MTX) is one of the most used drug in the treatment of solid tumors and inflammatory bowel diseases, however, because MTX highly cytotoxic and nonselectivity promotes several side effects. Its therapeutic efficacy is compromised due to the resistance acquired by tumor cells and it low intestinal permeability, mainly through the efflux mechanism of the free form. In this work, oral nanoparticles composed of chitosan (CS), hyaluronic acid (HA) and hydroxypropylmethylcellulose (HP) phthalate, polymers that have properties such as pH-dependent solubility, mucoadhesiveness and functionalization have been developed as a technological platform for the target of MTX to the colon, aiming the treatment of local pathologies. Molecular weight and second viral coefficient analyzes demonstrated the suitability of polymers and solvents to obtain nanostructures by the polyelectrolyte complexation method. The evaluation of the pH... (Complete abstract click electronic access below) / Mestre
333

Evaluation péropératoire de la perfusion viscérale à l'aide de la fluorescence couplée à la réalité augmentée / Real-time fluorescence-based enhanced reality for visceral perfusion evaluation

Diana, Michele 24 May 2016 (has links)
La perfusion intestinale est un facteur clé dans la guérison des anastomoses digestives. L'évaluation clinique de la perfusion demeure subjective et s’avère insuffisante pour prédire les complications anastomotiques, quelle que soit l'expérience du chirurgien. La vidéographie par fluorescence peut fournir une évaluation en temps réel de la perfusion intestinale. Suite à l'administration systémique d'une substance fluorescente, il est possible d’évaluer les unités de fluorescence, lorsque la zone d'intérêt est illuminée par une source de lumière spécifique. La présence de fluorescence est un marqueur de perfusion tissulaire mais cela reste une donnée subjective. Pour obtenir des données quantitatives, nous avons mis au point une solution d'analyse assistée par ordinateur permettant l'évaluation intraopératoire du site optimal de résection. Le logiciel peut générer une cartographie virtuelle de perfusion et celle-ci peut être superposée aux images laparoscopiques en pour obtenir l'effet de réalité augmentée. Cette thèse décrit le développement progressif de ce concept. / Pre-anastomotic bowel perfusion is a key factor for a successful healing process. Clinical evaluation of bowel perfusion is subjective and not accurate at predicting anastomotic complications, irrespective of the surgeon’s experience. Fluorescence videography analysis can provide real-time evaluation of bowel perfusion. Following the systemic administration of a fluorescent substance, fluorescence videography can compute the units of fluorescence, when the area of interest is illuminated by a specific light source. Fluorescence intensity is a marker of blood supply to the tissue. However, fluorescence intensity alone remains a subjective approach. We have developed a software solution enabling quantitative estimation of bowel perfusion, for intra-operative evaluation of the optimal resection site. The software can generate a “virtual perfusion cartography”, which can be overlapped onto real-time laparoscopic images to obtain the Enhanced Reality effect. This thesis describes the stepwise development of such concept.
334

Immunity against fungal beta 1,3 glucan carbohydrate in the gastrointestinal tract

Feliu, Marianela 17 June 2016 (has links)
Inflammatory Bowel Disease (IBD) is a debilitating, life- long disease that affects about 1.4 millions Americans. Little is known about the pathogenesis of IBD and an effective cure still remains to be discovered. While there are numerous T cell targeting therapies for IBD, more research is still needed. Bispecific T Cell Engagers, BiTES, is a modified protein capable of engaging two antigens simultaneously; it is capable of activating T cells by circumventing the MHC protein molecule. This provides an alternative to the current molecular therapies for IBD. In addition to monoclonal therapy research, there has been a plethora of research on immunomodulatory molecules, such as β- glucan. The benefit of β-glucan has been shown with supplements and food sources alike in animal models. In this study, we used BiTES, CMPD-1, with an anti-CD3/ Dectin-1 epitopes capable of engaging T Cells and β-glucan in beads and fungi cell wall. CMPD-1 is capable of engaging Splenic and Lamina Propia T Cells from a C57BL/6 mice. Likewise, CMPD-1 engaged T cells to hyphae of C. albicans and A. fumigatus, which have a higher concentration of β-glucan than in the candida form. The data show a delayed in hyphae growth in yeast with CMPD-1 and a decrease in yeast growth for the first four hours when compared to non- BiTES molecules. Additionally, qualitative analysis of CMPD-1 shows a decrease A. fumigatus growth after a 72-hour incubation period. Splenic T cells from mice lacking Dectin-1 and Wild-type (WT) mouse strains where incubated with BiTES compound and yeast for 23 hours followed by a PrestoBlue killing assay to assess yeast cell viability. The PrestoBlue assay showed that CMPD-1 killed more A. fumigatus in both T cell subsets; although, the difference lacked statistical significance. The applications of this molecule as a therapeutic agent for IBD are promising, although, still in its infancy. An alternative use for this molecule is to train the immune system with the BiTES molecule in conjunction with β-glucan supplements to build immunity against opportunistic pathogens such as A. fumigatus and C. albicans that often cause havoc in IBD patients as a result of the changes in microbiota, and compromised integrity of the GI tract. / 2017-06-16T00:00:00Z
335

Changes in fecal lactoferrin as a predictor of of steroid responsiveness in pediatric patients with ulcerative colitis

Murphy, Sean Thomas 18 June 2016 (has links)
INTRODUCTION: The management of pediatric patients with ulcerative colitis (UC) is dependent upon the ability to detect meaningful changes in disease status. This is currently done using validated patient-reported clinical disease activity indices, including the Pediatric Ulcerative Colitis Activity Index (PUCAI). While useful for global assessments completed during ambulatory office visits, the sensitivity of this metric may be insufficient to reflect more subtle changes in disease activity or response to medical therapy in hospitalized patients. Intravenous steroids are typically employed in the management of patients admitted for acute exacerbations of UC symptoms. These are typically manifest by worsening bloody diarrhea, abdominal pain, and worsening anemia. There is presently no way of predicting whether a patient admitted for UC will respond to steroid therapy. Current paradigms dictate a five-day trial before considering a transition to more potent medical or definitive surgical approaches to the management of refractory colitis. The development of more sensitive and reliable biomarkers or disease activity metrics could enable clinicians to more expediently identify steroid non-responders. This would minimize patient morbidity, decrease risk of complication, and lower overall cost of care. Previous studies have demonstrated that changes in fecal lactoferrin (FLA) correlate with disease activity in patients with UC. OBJECTIVES: To analyze the predictive value of FLA in the response to steroid treatment of patients admitted for management of UC. METHODS: We recruited pediatric inpatients with UC in the Division of Gastroenterology, Hepatology and Nutrition at Boston Children’s Hospital who were hospitalized for treatment of a flare of their UC symptoms. After obtaining patient consent, we collected a stool sample on days 1 and 3 of their hospital stay. We sent samples to TECHLAB® Inc. (Blacksburg, VA) to be analyzed for levels of FLA. We compared Day 1, Day 3 and ∆FLA (Day 1 – Day 3) in two patient groups: those that responded to conventional steroid therapy and those that required rescue medical or surgical therapy. We reported statistical significance with the Wilcoxon signed-rank test. RESULTS: Of 67 patients consented for the study, 30 provided stool samples on both days 1 and 3 of their inpatient hospitalization. Of the 30 patients, 63.3% responded to steroids while 36.7% required rescue therapy with immunomodulators. ∆FLA for responders, 43.6μg/mL(-239.0, 331.6) (median(interquartile range)), did not differ significantly from non-responders, -74.1μg/mL(-296.7, 221.7), P = 0.3. CONCLUSIONS: Our findings do not demonstrate that measurement of changes in quantitative FLA over three days can be used to assess acute responses to steroid therapy. Increasing the sample size may allow us to better delineate subtle differences between responders and non-responders to steroid therapy.
336

Metabolomic profiling in inflammatory bowel disease

Hildebrand, Diane Rosemary January 2017 (has links)
Introduction Inflammatory bowel disease (IBD) is a chronic gastrointestinal disorder that encompasses two major subtypes; Crohn’s Disease (CD) and Ulcerative Colitis (UC). Our knowledge regarding disease pathogesis is rapidly increasing. However, these disease entities provide challenges in diagnosis, monitoring of disease activity and assessing individual response to treatment, because there is a lack of validated clinical biomarkers. Metabolomics involves the study of numerous analytes that have very diverse physical and chemical properties and occur in a wide concentration range. Early evidence suggests there is potential for metabolomic profiling to be used in the differentiation of CD and UC. However, knowledge is limited regarding the metabolic changes seen in relation to disease activity or to medical or surgical treatments. Aims A metabolomics approach was taken to determine whether metabolomic profiles could distinguish between patients with CD or UC and healthy controls. We also aimed to define the relationship between metabolomic profile and disease activity, and to determine the effect of medical (anti-TNFa agents) and surgical treatment on the metabolome. Methods A metabolomics approach was undertaken. Serum and urine sample sets were collected from a total of 41 patients with ulcerative colitis, 43 patients with Crohn’s disease, and 62 healthy controls (HC). In order to allow a comparison of metablomic profile and disease activity, 4 sample sets were taken from the same patient at 3 monthly intervals over the period of one year. Those patients undergoing either surgical or biological treatment had sample sets taken pre and post intervention. Metabolomic analysis using gas chromatography time of flight mass spectrometry (GC-ToF-MS) and ultra-high performance liquid chromatography Fourier Transform mass spectrometry (UHPLC-FTMS) was carried out on both serum and urine. Results Serum and urine GC-ToF-MS and UHPLC-FTMS metabolomic analyses show differentiation between UC, CD and healthy controls, most significantly in urine analyses. No significant differentiation was seen in pre- and post-surgical patients, or pre- and post-biological therapy patients. It was possible to differentiate surgical patients from healthy controls, especially in the urine analyses. Metabolite identification revealed consistently more dietary variation in the healthy controls than in the IBD patients. Significant differences (p < 0.05) were seen between healthy controls and IBD patients in classes of metabolites relating to the citric acid cycle and the uronic acid pathway, as well as amino acids, fatty acids and cholesterols. The behaviour or location of disease, or the disease activity score did not appear to influence the metabolome in either serum or urine analyses using GC-ToF-MS and UHPLC-FTMS. Conclusion Metabolomic profiling of urine and serum in IBD may provide a novel methodology aiding both clinical diagnosis through biomarker development, and advancing knowledge of disease pathogenesis.
337

Estudo do polimorfismo do gene defb1 em pacientes com doença inflamatória intestinal e controles no sul do Brasil

Wilson, Timothy John January 2015 (has links)
Defensinas são peptídeos antimicrobianos produzidos na mucosa intestinal e fazem parte da imunidade inata, agindo sobre vários microrganismos luminais. Deficiência na expressão de defensinas tem sido relatada em doenças inflamatórias intestinais (DII), no entanto a contribuição de cada tipo de defensina, num cenário de polimorfismo genético, mantém alguma controversa. Βeta-defensinas humanas (HBDs) têm atividade antimicrobiana contra uma ampla variedade de fungos, bactérias e vírus e têm também, um papel na ligação entre a imunidade inata e adaptativa atuando como quimiotáticos. O gene DEFB1 (8p23), codificando a beta-defensina humana 1 (HBD-1), é expresso normalmente por células epiteliais de uma série de tecidos, mas sua expressão pode variar entre indivíduos e pode ser modificada durante processo inflamatório. Produção deficiente de defensinas parece contribuir para a patogênese de DII, e uma diminuição na expressão de HBD-1 tem sido relatada na mucosa de pacientes com doença de Crohn (DC) e retocolite ulcerativa (RCU). Nós avaliamos a possível associação de três polimorfismos do gene DEFB1 com a suscetibilidade a DII, RCU e DC, em 149 pacientes, 79 com DC e 70 com RCU; e 200 controles saudáveis do sul do Brasil. No nosso estudo não se observou diferença estatisticamente significativa entre a distribuição das frequências alélicas para DEFB1 SNPs -52G>A. -44C>G e -20G>A entre o total de pacientes com DII e controles. Porém, quando pacientes com DC foram estratificados de acordo com a localização anatômica, o alelo -20G>A foi mais frequente em pacientes com DC colônica do que em controles (65 % VS 44 %, p=0,048). De forma similar, o genótipo A/A foi mais frequente em pacientes com DC colônica do que em controles (36 % VS 16 %), mas neste caso, a diferença não foi estatisticamente significativa (p=0,07). Embora não se achou uma clara e forte associação entre os SNPs 5’-UTR DEFB1 e suscetibilidade/proteção à doença inflamatória intestinal, nossos resultados sugerem possível envolvimento do gene DEFB1 nestas enfermidades, especialmente com a localização colônica da doença de Crohn. Estudos com amostras maiores e populações diversas serão úteis para avaliar a tendência observada no nosso grupo. / Defensins are antimicrobial peptides produced by the intestinal mucosa and are part of the innate immune system, playing a protective role against various intestinal microorganisms. Deficiency in the expression of defensins has been reported in inflammatory bowel diseases (IBD), however there is some controversy over the contribution of each type of defensine, in a setting of great genetic polymorphism. Beta-defensins (HBDs) have an antimicrobial activity against a great variety of fungi, bacteria and viruses, and also have a role in connecting the innate and the adaptive immunity, acting as a chemostatic agent. Deficient production of defensins appears to contribute to the pathogenesis of IBD, and the lower expression of HBD-1 has been reported on the mucosa of Ulcerative colitis (UC) and Crohn’s disease (CD) patients. We evaluated a possible association of three polymorphisms of gene DEFB1 with susceptibility to develop IBD, UC and CD in 149 patients, 79 with CD and 70 with UC; and 200 healthy controls from the south of Brazil. The gene DEFB1 (8p23), which codifies human beta-defensin 1 (HBD-1), is constitutivelly expressed by epithelial cells of several tissues, but its expression may vary among different individuals and may be modified by inflammation. In our study we did not find a statistically significant difference between the distribution of the allelic frequencies for DEFB1 SNPs -52G>A, -44C.G and -20G>A between the total number of patients and controls. However, when patients were stratified according to the anatomic location, the allele -20G>A was more frequent in patients with colonic CD than in contros (65% VS 44%, p=0,048). Similarly, the genotype A/A was more frequent in patients with colonic CD than in controls (36% vs 16%), however, in this case, the difference wasn’t statistically significant (p=0,07). Although we did not find a clear and strong association between the 5’-UTR DEFB1 SNP and susceptibility to IBD, our results suggest a possible involvement of the DEFB1 gene and these diseases, particularlly colonic CD. Further studies with larger samples and diverse populations will be usefull to evaluate the trend observed by our group.
338

Perfil da resposta Th1/Th2 no fluido gengival de pacientes portadores de doença inflamatória intestinal com periodontite crônica / Th cell profile in the gingival crevicular fluid from inflammatory bowel disease patients with chronic periodontitis

Fernanda de Brito Silva 01 August 2008 (has links)
O objetivo dessa tese foi avaliar a expressão de citocinas Th1 (IL-12 e INF&#61543;), citocinas Th2 (IL-4, IL-6 e IL-10) e das citocinas pró-inflamatórias IL-18, IL-1&#61538; e TNF&#61537; no fluido gengival de pacientes com periodontite crônica portadores da doença de Crohn (DC), de retocolite ulcerativa idiopática (RCUI) e em indivíduos saudáveis (o grupo controle, GC). Como objetivo secundário, avaliamos a função dos neutrófilos no fluido gengival desses pacientes através da mensuração das metaloproteinases da matriz -8, -9 (MMP-8 e MMP-9) e da atividade da elastase. Quinze pacientes com DC (idade média 38.2 11.4 anos), 15 pacientes com RCUI (idade média 45.0 10.5 anos) e 15 pacientes saudáveis (idade média 42.1 7.8 anos) participaram desse estudo. Todos os dentes presentes, com exceção dos terceiros molares, foram examinados. Profundidade de bolsa (PB), nível de inserção clínica (NI), presença de placa e de sangramento a sondagem foram avaliados em seis sítios por dente. Em cada paciente, o fluido de 4 sítios com periodontite (PB &#61619; 5 mm e NI&#61619; 3mm) e de 4 sítios com gengivite (PB&#61603; 3 mm e NI &#61603; 1 mm) foram coletados através de pontas de papel absorvente pré-fabricadas. O sistema LUMINEX foi utilizado na mensuração das IL-1&#61538;, IL-4, IL-6, IL-10, IL-12p70, TNF&#61537;, INF&#61543;, MMP-8 e MMP-9. A IL-18 foi analisada através do ensaio ELISA e a atividade de elastase através de uma reação enzimática. O soro desses pacientes também foi analisado e o coeficiente de correlação de Pearson foi utilizado na análise da correlação entre as citocinas no soro e no fluido gengival. Nos sítios com gengivite, a quantidade total de IL-4 foi significativamente menor no grupo RCUI do que no grupo GC (p=0.016). Nos sítios com periodontite, a quantidade total de IL-4 foi significativamente menor no grupo DC do que no grupo GC (p=0.029). A quantidade total da IL-6 (p=0.028) assim como sua concentração (p=0.044) foram significativamente maiores no grupo RCUI do que no grupo GC. No soro, os níveis da IL-18 foram significativamente mais altos nos grupos DC (p=0.011) e RCUI (p=0.019) do que no grupo GC. No grupo RCUI, a IL-18 do soro se correlacionou positivamente com a IL-1&#61538; do fluido gengival (r=0. 667, p=0.01). Concluindo, nos pacientes com doença inflamatória intestinal, os níveis da IL-4 estavam mais baixos no fluido gengival e os níveis da IL-18 estavam aumentados no soro quando comparados aos controles. A função dos neutrófilos foi similar entre os pacientes com doença inflamatória intestinal e os controles. Com exceção da correlação positiva entre a IL-18 sérica e a IL-1&#61538; no fluido gengival dos pacientes com retocolite ulcerativa idiopática, não houve correlação entre as diversas citocinas mensuradas no soro e as citocinas mensuradas no fluido gengival nos controles nem nos pacientes com doença inflamatória intestinal. Não houve a caracterização de um padrão de resposta Th1 ou Th2 no fluido gengival dos pacientes com doença inflamatória intestinal. / The aim of this thesis was to evaluate the expression of Th1 cytokines (IL-12 and INF-&#947;), Th2 cytokines (IL-4, IL-6 and IL-10) and the pro-inflammatory cytokines IL-18, IL-1&#61538; and TNF-&#945; in the gingival crevicular fluid (GCF) from Crohns disease (CD) patients, ulcerative colitis (UC) patients and healthy individuals (control group, CG) who had chronic periodontitis. Besides, we measured elastase activity, matrix metalloproteinase -8 and -9 (MMP-8 and -9) to address the neutrophil function in the GCF. Fifteen CD patients (mean age 38.2 &#61617; 11.4 years), 15 UC patients (mean age 45.0 &#61617; 10.5 years) and 15 systemically healthy controls (mean age 42.1 &#61617; 7.8 years) were enrolled in this study. All the present teeth, except for the third molars were examined. Probing pocket depth (PPD), clinical attachment loss (CAL), presence of plaque and presence of bleeding on probing were assessed in six sites per tooth. In every subject, GCF from 4 gingivitis sites (PPD &#61603; 3mm and CAL &#61603; 1mm) and from 4 periodontitis sites (PPD &#61619; 5mm and CAL&#61619; 3mm) were collected with filter strips. The data were reported as total amount and concentration. IL-1&#61538;, IL-4, IL-6, IL-10, IL-12p70, TNF&#945;, INF&#947;, MMP-8 and MMP-9 were analyzed by the Luminex analyzer. IL-18 was analyzed using a commercially available ELISA assay and the elastase activity by an enzymatic reaction. The serum was also analysed and the correlations between the cytokines in the GCF and in the serum were calculated by Pearson correlation analysis. In gingivitis sites, the total amount of IL-4 was significantly lower in the UC group than in the CG group (p=0.016). In periodontitis sites, the total amount of IL-4 was significantly lower in CD group than in the CG group (p=0.029). The total amount of IL-4 was lower in UC group than in CD group (p=0.077). Similarly, IL-4 concentrations in both CD (p=0.096) and UC (p=0.064) groups were lower than in CG group. IL-6 total amount (p=0.028) and IL-6 concentration (p=0.044) were significantly higher in the UC group than in the CG group. In the serum, IL-18 levels were significantly higher in CD (p=0.011) and UC (p=0.019) groups than in the CG group. In UC group, there was a positive correlation between serum IL-18 levels and IL-1&#61538; in the GCF (r=0. 667, p=0.01). In conclusion, IBD patients had lower IL-4 levels in the GCF and higher IL-18 levels in the serum than healthy controls. The neutrophil function in IBD patients is similar to controls. Except for the positive correlation between IL-18 in the serum and IL-1&#61538; in the GCF, there was no correlation between the cytokines in serum and in the GCF either in IBD patients or in controls. There was not a Th1 or Th2 polarization in the GCF from IBD patients.
339

Estudo dos polimorfismos C1236T, G2677T e C3435T do gene MDR1 em pacientes portadores de doenças inflamatórias intestinais / Study of C1236T, G2677T, C3435T MDR1 gene polymorphisms in patients with inflammatory bowel disease

Renata de Sá Brito Fróes 25 January 2013 (has links)
Estudos recentes têm avaliado a presença de polimorfismos do gene multidroga resistente 1 (MDR1), que codifica o transportador de membrana de efluxo chamado de P-glicoproteína, seu potencial papel na suscetibilidade das doenças inflamatórias intestinais (DII) e suas possíveis correlações com aspectos clínicos das DII. Dados conflitantes podem resultar da análise genética de populações distintas. Investigamos se os polimorfismos do gene MDR1 estão associados com as DII em população do sudeste do Brasil e suas possíveis correlações com fenótipos, atividade de doença, resposta ao tratamento e efeitos colaterais. Como métodos, a presente pesquisa trabalhou com 146 pacientes com Doença de Crohn (DC) e 90 com Retocolite Ulcerativa Idiopática (RCUI), que foram recrutados através de critérios diagnósticos estabelecidos. Os polimorfismos do MDR1 mais comumente descritos na literatura, C1236T, G2677T e C3435T, foram avaliados por PCR. As frequências genotípicas de pacientes com RCUI e DC foram analisadas na população de estudo. Associações de genótipo-fenótipo com características clínicas foram estabelecidas e riscos estimados para as mutações foram calculados. Nenhuma diferença significativa foi observada nas freqüências genotípicas para os polimorfismos G2677T/A e C3435T do MDR1 na DC ou na RCUI. O polimorfismo C1236T foi significativamente mais comum na DC do que na RCUI (p = 0,036). Na RCUI foram encontrados mais homens nos polimorfismos C1236T e G2677T no grupo de heterozigotos. Foram encontradas associações significativas entre o polimorfismo C3435T do gene MDR1 em pacientes com fenótipo estenosante na DC (OR: 3,16, p = 0,036), em oposição ao comportamento penetrante (OR: 0,31, p = 0,076). Na DC, associações positivas também foram encontradas entre o polimorfismo C3435T, à atividade moderada/severa da doença (OR: 3,54, p = 0,046), e à resistência / refratariedade ao corticosteróide (OR: 3,29, p = 0,043) nos homozigotos polimórficos. Nenhuma associação significativa foi encontrada entre os polimorfismos do MDR1 e categorias fenotípicas, atividade de doença ou resposta ao tratamento da RCUI. Em conclusão, os resultados do presente estudo sugerem que os polimorfismos do gene MDR1 poderiam estar implicados na susceptibilidade a DC e no seu fenótipo estenosante, como também estarem associados com uma resposta inadequada ao tratamento em um grupo de pacientes com DC. A forte relação com a DC suporta a existência de papéis adicionais para o MDR1 em mecanismos específicos subjacentes na patogênese da DC, como o controle da microbiota intestinal, mediação e regulação da fibrose. Além disso, compreender os efeitos de vários fármacos associados a estas variantes do MDR1 pode contribuir para a prescrição personalizada de regimes terapêuticos.
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Intestinal stromal cell types in health and inflammatory bowel disease uncovered by single-cell transcriptomics

Kinchen, James January 2017 (has links)
Colonic stromal cells provide critical structural support but also regulate immunity, tolerance and inflammatory responses in the mucosa. Substantial variability and plasticity of mucosal stromal cells has been reported but a paucity of distinct marker genes exist to identify distinct cell states. Here single-cell RNA-sequencing is used to document heterogeneity and subtype specific markers of individual colonic stromal cells in human and mouse. Marker-free transcriptional clustering of fibroblast-like cells derived from healthy human tissue reveals distinct populations corresponding to myofibroblasts and three transcriptionally and functionally dissimilar populations of fibroblasts. A SOX6 high fibroblast subset occupies a position adjacent to the epithelial basement membrane and expresses multiple epithelial morphogens including WNT5A and BMP2. Additional fibroblast subtypes show specific enrichment for chemokine signalling and prostaglandin E<sub>2</sub> synthesis respectively. In ulcerative colitis, substantial remodelling occurs with depletion of the SOX6 high population and emergence of an immune enriched population expressing genes associated with fibroblastic reticular cells including CCL19, CCL21 and IL33. A large murine dataset comprising over 7,000 colonic mesenchymal cells from an acute colitis model and matched healthy controls reveals strong preservation of the SOX6 high and myofibroblast transcriptional signatures. Unsupervised pseudotemporal ordering is used to relate fibroblast subsets to one another producing a branched developmental hierarchy that includes a potential progenitor population with mesothelial characteristics at its origin. This work provides a molecular basis for re-classification of colonic stromal cells and identifies pathological changes in these cells underpinning inflammation in UC.

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