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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.
261

Dysbiosis in inflammatory bowel disease promotes clostridium difficile colonization

Hafften, Nicholas 08 April 2016 (has links)
Research into the gut microbiome has revealed the widespread influence that microbial species have on their host. Host genetics and environmental factors influence the abundance and diversity of the bacterial species living within the gastrointestinal tract. When the normal composition of the gut microbiota is altered, a dysbiotic state incurs. Inflammatory bowel disease (IBD) is a chronic/relapsing inflammatory disorder of the intestinal mucosa, which is characterized by a state of dysbiosis. Despite the large amount of information studying the role dysbiosis has in the pathogenesis of IBD, it is not clear how the altered microbial composition of the gut in IBD patients leads to susceptibility to enteric pathogens such as Clostridium difficile. This study aims to highlight the features of the gastrointestinal tract that are modified as a result of dysbiosis in the IBD population, and how these features facilitate colonization by C. difficile and symptom development. Review of the available literature demonstrated that the depletion of Clostridial cluster XIVa in IBD-associated dysbiosis alters bile acid metabolism and butyrate fermentation in the colon, ultimately promoting germination of C. difficile spores and weakening the gut's immune response against toxin-mediated inflammation. From continued research into the gut microbiota, more will be understood of how these microbial organisms influence human health and disease.
262

The impact of parental and child coping strategies on disease outcomes and emotional well-being in children with newly diagnosed inflammatory bowel disease

Wilson, Jennifer Kelly 25 July 2018 (has links)
BACKGROUND: Inflammatory Bowel Disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), are chronic inflammatory conditions of the bowel that display a rising prevalence in childhood and adolescence. The diagnosis of a chronic condition, such as IBD, in childhood can be overwhelming and stressful for both the patient and caregiver. Parents and family members can play a critical role in providing emotional support for children with newly diagnosed IBD. We hypothesized that dysfunctional patient and parental coping strategies would correlate with increased anxiety and depression in children, worsening clinical disease activity, and increased healthcare utilization. OBJECTIVE: The primary objective of the IBD Coping Study is to assess the stability of coping strategies and psychological stress over the first year following a new diagnosis of IBD. Secondarily, we aim to assess the impact of child and parental coping strategies on disease activity and emotional well-being over the year. METHODS: This is a prospective, longitudinal cohort study of children with newly diagnosed IBD and their parents at Boston Children's Hospital (BCH). Patients between the ages of 9 and 17 years old that have been diagnosed with CD, UC or Indeterminate colitis (IC) within the last 6 months, are English-speaking, and receive routine care at BCH are approached for participation in our study. Participation includes the completion of previously validated psychological metrics for both child and parent at baseline and then again 12 months later. Our instruments include the Children's Depression Inventory (CDI), the Screen for Child Anxiety Related Disorders (SCARED), the IMPACT-III Questionnaire, the Patient Health Questionnaire (PHQ-9), Healthcare Utilization Survey, Pediatric Inventory for Parents (PIP), and the Hospital Anxiety and Depression Scale (HADS). RESULTS: We screened 187 patients with IBD for participation in our study, and roughly 30% of them were eligible for recruitment. To date, we have enrolled a total of 30 patients. Of these patients, there was an equal distribution of male and female participants. The majority of patients were around 14 years of age at the time of IBD diagnosis with a greater number of patients with CD (17) currently represented. We are approaching patients on average about 1.5 months after their initial diagnosis. The baseline average Pediatric Ulcerative Colitis Activity Index (PUCAI) score was 21.15 ± 20.53, whereas the average Pediatric Crohn's Disease Activity Index (PCDAI) score was 3.75 ± 2.50. On CDI items, teenage girls and boys reported increased raw and standardized scores (Raw: 5.83 and 4.83, respectively; Standardized: 43.67 and 44.67, respectively) than their younger counterparts for depressive behaviors, including negative mood and interpersonal problems. Pediatric patients encountered as inpatients reported an overall lower quality of life on IMPACT-III items (103.29 ± 15.11) than those approached in the ambulatory setting (140.36 ± 7.50). On SCARED items, patients met criteria for the potential presence of one or more anxiety disorders. Inpatients also reported being bothered more frequently with respect to hindrances in their sleep, appetite, and daily routines on the PHQ-9 metric. Parents of children with newly diagnosed IBD rely on increased communication with their child's primary GI provider, and their scores reflected lower emotional functioning during an admission period when compared to scores reported during regular scheduled ambulatory visits. Scores collected from the HADS screen demonstrate that 6% and 33% of parents reported a score great enough to be considered a "borderline case" for depression and anxiety measures, respectively. Primary comparisons between child health assessments and parent healthcare utilization depicted concurrent elevations in the same child-parent pair at baseline. CONCLUSION: Our initial findings suggest a clear disparity between emotional stability in children and their parents in outpatient and inpatient settings following a new IBD diagnosis. Healthcare utilization by parents may be linked to adaptive or maladaptive coping, and continuation of our study will substantiate this prediction. In looking ahead, potential interventions may require approaches stratified by age, gender, and hospital setting. Our study supports the need for further investigations into the impact of targeted interventions that promote an improvement in overall quality of life in children with IBD and their family during the first year of post-diagnosis.
263

Algumas propriedades de virulência de Escherichia coli isoladas de pacientes com doença inflamatória intestinal. / Some virulence properties of Escherichia coli isolated from patients with inflammatory bowel disease.

Danyelle Amélia Grecco Samegima 22 August 2008 (has links)
Escherichia coli tem um predomínio anormal em pacientes com doença inflamatória intestinal (DII), mas a razão deste aumento numérico é desconhecida. Amostras de E. coli (131) foram isoladas de biópsias retais de 27 pacientes com retocolite ulcerativa (RCU), 8 pacientes com doença de Chron (DC) e 19 controles. E. coli enteroagregativa (EAEC) foram detectadas no ensaio de adesão de 3 horas a células HEp-2 em 71,4% dos pacientes com DII e em 26,3% dos controles (P<0,02). As cepas de pacientes com DC foram negativas para outros marcadores. Duas cepas invasivas foram detectadas entre pacientes com RCU, três deles tinham cepas com plasmídio de adesão agregativa (pAA) e fímbria de adesão agreagativa (aggR) e outras quatro possuíam o gene attaching and effacing (eae). Nenhuma cepa abrigava locus associado à invasão (ial) e antígeno plasmidial de invasão (ipaH). De acordo com esses resultados, EAEC é o grupo dominante encontrado na mucosa colônica de pacientes com DII, mas somente aquelas encontradas em pacientes com RCU abrigam marcadores de virulência tradicionais. / Escherichia coli are increased in inflammatory bowel disease (IBD) patients, but the reason for this elevation is unknown. Amongst their properties is the interaction with cultured epithelial cells. Rectal biopsies from 27 ulcerative colitis (UC), 8 Crohns disease (CD) and 19 control patients were cultured for E. coli, given 131 isolates. Enteroagregative E. coli (EAEC) strains, as detected in 3h adherence assays to HEp-2 cells, were found in 71.4% of 35 IBD patients and in 26.3% of controls (P<0.02). Two highly invasive strains were detected among UC patients, three of whom had also strains with both plasmid of aggregative adhesion (pAA) and aggregative adherence fimbriae R (aggR) and another four E. coli attaching and effacing (eae). No strains had invasion-associated locus (ial) and invasion plasmid antigen H (ipaH), and those from CD were also negative for other markers. According to these results, EAEC are the dominant E. coli group found in the colonic mucosa of IBD patients, but only those found in UC patients seem to harbor traditional virulence markers.
264

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.
265

Partners upplevelse av att leva med en person som har kort tarm syndrom : En kvalitativ intervjustudie

Johansson, Anna-Carin, Ohlén, Ingela January 2012 (has links)
Short bowel syndrome (SBS) är ett tillstånd som uppkommer hos personer som har förlorat stora segment av tarmen vilket resulterar i malnutrition och de som har mindre än 2 meter tarm är mycket utsatta. Forskningen visar att det är många aspekter av livet som berörs för de personer som drabbats av SBS och det medför en förändrad livssituation för den sjuke personen. Förändringarna påverkar inte bara den som är drabbad utan även familjen, så som en partner. För att öka vårdarens förståelse för dessa partners situation är det viktigt att uppmärksamma och belysa deras upplevelse. Syftet med studien är att belysa partners upplevelse av att leva med någon som har SBS. Sju personer som lever med en partner som har SBS har intervjuats och analyserats utifrån kvalitativ innehållsanalys. I analysen framkom fem kategorier; förändringar i livet, känslor av uppgivenhet, påverkan på relationen, oro och stöd. Resultatet av denna studie visar att det är många aspekter i livet som påverkas av sjukdomen vilket också berör den sjukas partner. Det framkom att partnern fick göra många anpassningar i sitt liv runt den sjukas behov och det var måltider, toalettbesök och ibland parenteral nutrition som fick styra vardagens planering. De kvinnliga deltagarna i studien uttryckte en känsla av ansvar för familjen, men även för sin sjuka partner periodvis och upplevde det mycket påfrestande. Stödet till den sjuka hade varit bra, men deltagarna upplevde en saknad av stöd och information till de som anhörig. / Program: Specialistsjuksköterskeutbildning med inriktning mot distriktssköterska
266

Serine hydrolase activity and roles for monoacylglycerol lipase in innate immunity and intestinal inflammation

Ambrose, Timothy James William January 2018 (has links)
Detection of evolutionarily conserved pathogen motifs by pattern recognition receptors (PRRs), particularly on dendritic cells (DCs), is crucial for adequate immune responses. Defects in DC function are known to be associated with inflammatory bowel disease (IBD). The endocannabinoid system (ECS) is the system through which exocannabinoids such as Δ<sup>9</sup>-tetrahydrocannabinol and cannabidiol signal. Regarding inflammation, cannabinoids generally exert anti-inflammatory effects, including on experimental colitis. However, most work has been performed in animal models and less is known about the function of this system in human immune cells, particularly DCs. Monoacylglycerol lipase (MGLL) is the key enzyme for hydrolysis of the endocannabinoid 2-arachidonoylglycerol, and a member of the serine hydrolase enzyme superfamily. This thesis defines the activity of serine hydrolase enzymes for the first time in human DCs upon stimulation by NOD2/TLR2 ligands using activity-based protein profiling (ABPP). MGLL is shown to be ubiquitously upregulated upon stimulation of DCs and in monocyte-derived macrophages. Through pharmacological inhibition studies, MGLL is demonstrated to regulate cellular and secreted lipids, not limited to endocannabinoids. However, overall DC function is independent of this enzyme suggesting that the effects of lipid modulation may be on bystander cells. Challenging the current literature, MGLL inhibition with a novel inhibitor worsens murine Citrobacter rodentium colitis. Finally, ABPP demonstrates a rich serine hydrolome in colonic tissue from human IBD with many enzymes previously undefined in this disease. Gene expression of ECS components suggests the enzymes ABHD12 and DAGLα/β may be potential markers of field change in IBD.
267

Biomarker discovery in inflammatory bowel diseases

Kalla, Rahul January 2018 (has links)
There is an unmet need for novel biomarker discovery in Inflammatory Bowel Diseases (IBD) to aid clinical management in several clinical settings including diagnosis and prognosis. With an ever-advancing repertoire of biological therapies on the horizon, it is important to personalise treatments at an early stage. The aim of this thesis is to explore the clinical utility of novel blood-based biomarkers in diagnosis, disease classification and prognosis in 2 cohorts: newly diagnosed IBD and acute severe colitis. Investigating the circulating methylome, 290 probes exhibited Holm significant IBD-associated methylation differences, including VMP1/MIR21 (p=7.5×10-14) and RPS6KA2 (1.1×10-19) and were consistent within the European cohort. 11 Differentially methylated positions (DMPs) predicted treatment escalation after Holm adjustment (top probe p=0.003). A panel of 6 probes identified 2 patient subgroups that have significantly different disease courses (Hazard Ratio (HR) 10.5, 95%CI: 4.3-25.6; logrank p=1.5×10-24). The 6 probe marker outperformed conventional biomarkers in predicting treatment escalation (hsCRP > 4mg/L, HR 3.2(1.7-5.8), logrank p=0.0004 and Alb < 36g/L, HR 2.9(1.5-5.6), p=0.0001). Within the same cohort, a novel proximity extension assay (PEA) was then utilised to identify novel diagnostic and prognostic protein markers. 61 proteins were significantly associated with IBD including MMP12 (Holm-adjusted p=4.1×10-26). A total of 9 proteins predicted disease course in this cohort. Using a panel of 7 randomly selected top prognostic probes, 2 patient groups were identified that had significantly different disease courses: logrank p=2.2×10-10, HR 5.6(2.0-15.6), outperforming conventional biomarkers in predicting treatment escalation (hsCRP > 4mg/L, HR 3.2(1.7- 5.8), logrank p=0.0003 and Alb < 36g/L, HR 2.7(1.4-5.2), p=0.0004). In a subcohort, serum calprotectin (SC) and conventional blood markers were investigated for their utility in diagnosis and prognosis in IBD. SC performed at par with CRP at differentiating IBD from controls with an area under the curve (AUC) of 0.87 (CI 0.81-0.92). For prognostication, both albumin and SC remained significant predictors of treatment escalation in IBD (logrank test p=5.1×10-5). MicroRNAs (miRNA) are small non-coding nucleic acids that have the capacity to modulate gene expression. Using small RNA sequencing in acute severe colitis (ASUC) and healthy controls (HC), 10 serum-based miRNA markers were significantly associated with acute severe colitis, including miR-30a-5p. Validating the findings using qPCR, miR-30a-5p was downregulated in ASUC (p=0.003). Furthermore, miR30a-5p remained a significant predictor of eventual colectomy in acute colitis (logrank test p=0.0014). These data highlight the translational potential for methylation, miRNA and proteomic biomarkers in diagnosing and prognosticating in IBD.
268

Epigenetic biomarker discovery in inflammatory bowel disease : unearthing clues for disease pathogenesis?

Ventham, Nicholas Toby January 2017 (has links)
Epigenetic alterations including DNA methylation and microRNAs may provide important insights into gene-environment interaction in complex immune diseases such as inflammatory bowel disease (IBD). An integrative genome-wide approach was used to analyse whole blood genetic, DNA methylation and gene expression data in 240 newly diagnosed IBD patients and 190 controls. Using the Illumina 450k array, differences in whole blood DNA methylation were observed in IBD cases versus controls including 439 differentially methylated positions (DMPs) and 5 differentially methylated regions (DMRs). The top DMP (RPS6KA2, discovery Holm adjusted p=1.22×10-16, replication p=1×10-9) and DMRs (VMP1, ITGB2, TXK) were replicated in an independent cohort using pyrosequencing. Paired genetic and epigenetic data allowed the identification of methylation quantitative trait loci (meQTL); two of the five DMRs (VMP1, ITGB2) demonstrated significant association with genetic polymorphisms. Methylation in the VMP1/microRNA-21 region was significantly associated with two single nucleotide polymorphisms (cg18942579 -rs10853015 [meQTL FDR adjusted p=9.4 × 10-5], cg16936953 - rs8078424 [meQTL FDR adjusted p=8.8 × 10-5]), both of which are in linkage disequilibrium with a known IBD susceptibility variant (rs1292053). Separated leukocyte methylation data highlight the cell type of origin of epigenetic signals seen in whole blood. IBD-associated hypermethylation within the TXK gene transcription start-site negatively correlated with gene expression in whole blood and CD8+ T-cells, but not other cell types, highlighting that cell-specificity and gene location-specificity of DNA methylation change is critical when associating methylation and gene expression. These data offer significant translational potential as diagnostic biomarkers. Least absolute shrinkage and selection operator (lasso) modelling identified 30 methylation probes can be used to accurately discriminate IBD cases from controls (Area under receiver operating characteristic curve = 0.898, sensitivity = 90.6%, specificity = 84.7%). MicroRNAs (miRNA) are small non-coding nucleic acids that have the capacity to modulate gene expression. MiRNAs have been increasingly implicated in many of the important IBD pathogenic pathways including autophagy, intestinal epithelial barrier integrity and the Th17 pathway. In common with all epigenetic mechanisms, miRNA expression is dynamic and cell-specific. Small RNA sequencing (RNA-seq) was performed on RNA extracted from CD14+, CD4+ and CD8+ cells isolated from 8 newly diagnosed cases of ileal or ileocolonic CD and 8 age and sex matched controls. There was a median of 2.4 million reads per sample (range 132,800-12.8 million reads per sample). One microRNA was differentially expressed in CD compared with controls (hsa-miR-503-5p log fold change = 0.7, FDR adjusted p = 9.1 × 10-5) in CD4+ lymphocytes, however this finding did not remain significant when alternative normalisation methods were used. The small number of cases used in microRNA analyses raises the possibility of both type I and II error, and limits the ability to draw firm conclusion from this series of experiments. Site-specific differences in DNA methylation in IBD relate to underlying genotype and associate with cell-specific alteration in gene expression. This is the most detailed characterisation of the epigenome carried out in IBD to date. The findings strongly validate this approach in complex disease, are replicable, and provide clear translational opportunities.
269

A new antibacterial agent : in vitro bacteriological characterization and in vitro/in vivo performance of sustained release formulations / Un nouvel agent antibactérien : caractérisation bactériologique in vitro et performance des formulations à libération prolongée in vitro/in vivo

Nieto Bobadilla, Maria Susana 08 September 2015 (has links)
Introduction : La résistance aux antibiotiques est une menace de santé, il est donc urgent de développer de nouveaux antibactériens. CIN-102, est un nouvel antibactérien développé par une industrie pharmaceutique. Il possède un large-spectre d’action et aucune résistance n’a été développée jusqu’à présent. Parmi les possibles applications thérapeutiques du CIN-102, notre recherche s’est focalisée sur les Maladies Inflammatoires Chroniques de l’Intestin (MICIs). Plusieurs facteurs contribuent à l’étiologie des MICIs. Les bactéries intestinales jouent un rôle important dans ces maladies et une augmentation de la charge bactérienne est observée pendant l’inflammation. Les objectifs de ce travail ont été : la caractérisation de l’activité antibactérienne du CIN-102, l’analyse de l’activité antibactérienne des agents anti-inflammatoires et antibiotiques utilisés en cas de MICI et la fabrication des formulations à ciblage colique pour le CIN-102. Le but est de diminuer la charge bactérienne colique par moyen du CIN-102 et améliorer, de cette façon, l’état de l’inflammation.Méthodes: La Concentration Minimale Inhibitrice (CMI), l’Effet Post-Antibiotique (EPA) et le temps de réduction logarithmique du CIN-102 ont été déterminés pour des bactéries aérobies et anaérobies. Les interactions entre le CIN-102 et des antibiotiques sur le marché ont été évaluées. La CMI de l’acide 5-aminosalicylique (5-ASA), GED-0507-34 et antibiotiques ont été déterminées pour des souches anaérobiques. Par rapport aux formulations à libération prolongée : des mini-granules contenant le CIN-102 ont été fabriqués par extrusion-sphéronisation puis pelliculés avec des mélanges de polymères insolubles et polysaccharides. Parallèlement, des mini-comprimés de CIN-102 ont été fabriqués par compression directe. La libération du CIN-102 in vitro, a été mesurée dans des milieux simulant l’estomac et l’intestin grêle. L’efficacité des systèmes à libération prolongée a été évaluée dans un modèle de colite chez la souris. Des prélèvements de selles et tissus coliques ont été soumis à des études bactériologiques. L’expression des cytokines a été mesurée à partir des tissus coliques.Résultats et discussion : Le large-spectre d’action du CIN-102 a été confirmé. Toutes les souches ont été inhibées par le CIN-102. CIN-102 présente un EPA et un temps de réduction logarithmique court. Il présente des interactions synergiques avec plusieurs antibiotiques, notamment la colistine et les aminoglycosides, en les rendant actifs contre des bactéries multirésistantes. Ces résultats in vitro doivent être poursuivis par des études chez l’animal. Des agents anti-inflammatoires utilisés contre les MICIs ne possèdent pas d’activité antibactérienne. Par ailleurs, les antibiotiques testés n’ont pas un large-spectre d’action contre des bactéries anaérobies généralement retrouvées dans l’intestin. Cela confirme le besoin d’un antibiotique à large spectre capable de réduire des charges bactériennes en cas d’inflammation. Dans ce but, des formulations capables de délivrer CIN-102 au niveau du colon ont été étudiées. La libération du CIN-102 des mini-granules pelliculés et mini-comprimés a été réduite dans des milieux simulant l’estomac et l’intestin grêle. Des souris atteintes de colite et traitées avec les formulations du CIN-102 ont eu une diminution des diarrhées et du sang dans les selles. Les concentrations d’entérobactéries adhérentes à la muqueuse colique et dans les selles ont été significativement réduites chez les souris traitées avec le CIN-102. Ces résultats montrent que ces formulations peuvent délivrer CIN-102 dans le tractus gastro-intestinal inferieur, et que la diminution d’entérobactéries semble réduire les symptômes de la colite.Conclusion : CIN-102 est un nouvel antibactérien a large-spectre et des formulations à libération prolongée peuvent délivrer cet agent dans le colon, diminuant la charge d’entérobactéries qui pourrait influencer l’état de l’inflammation. / Introduction: Antibiotic resistance is a major threat to public health and new antimicrobials are urgently needed. CIN-102, a new antibacterial agent which resembles cinnamon essential oils composition, was developed by a pharmaceutical company. CIN-102 had a broad-spectrum of action and resistance was not developed until now. Between all the possible therapeutic applications for CIN-102, a future utilization against Inflammatory Bowel Diseases (IBD) is aimed. IBD are chronic pathologies with a multifactorial etiology. In this context, enteric bacteria are well-known to have an important role, and higher bacterial concentrations are found in the intestine under inflammatory conditions. The objectives of this work were: to characterize the bacteriological activity of CIN-102, to analyze the bacteriological activity of anti-inflammatory agents and antibiotics used in IBD and to fabricate multiparticulate CIN-102 pharmaceutical forms for colonic targeted drug release. The idea is to use CIN-102 to reduce colonic bacterial loads and improve the state of intestinal inflammation. Methodology: The Minimal Inhibitory Concentration (MIC), the Post-Antibiotic Effect (PAE) and the logarithmic reduction time of CIN-102 were determined against several aerobic and anaerobic bacterial isolates. The interactions between CIN-102 and commercialized antibiotics were evaluated. The MIC of 5-aminosalicilyc acid, GED-0507-34 and antibiotics were determined for anaerobic bacterial isolates. Concerning sustained released formulations: CIN-102 pellet cores were fabricated by extrusion-spheronization and subsequently coated with blends of insoluble polymers and natural biodegradable polysaccharides. CIN-102 mini-tablets were fabricated by direct compression. In vitro drug released was measured in simulated gastric and intestinal fluid. The efficacy of best sustained release formulations was assessed in a murine model of colitis. Samples of luminal contents and sections of the colon were taken to perform a bacteriological analysis. Expression of cytokines was analyzed from colonic tissues.Results and discussion: The broad-spectrum activity of CIN-102 was confirmed. All aerobic and anaerobic strains were susceptible to CIN-102. Furthermore, CIN-102 had an important PAE and exerted a fast logarithmic reduction of bacterial inoculum. It interacts synergistically with several antibiotics, mostly with colistin and aminoglycosides, restoring the antibiotic activity against multi-resistant bacteria. The promising in vitro activity of CIN-102 has to be further confirmed by animal studies. Anti-inflammatory agents used against IBD were not provided of antibacterial activity and neither of the antibiotics tested possessed a broad-spectrum of action against anaerobic isolates commonly found in the intestine. These results confirm the need of a broad-spectrum antibiotic capable of reduced increased bacterial loads during inflammation. Following this aim, oral dosage forms able to deliver CIN-102 into the colon were studied. Concerning the sustained release forms, in vitro CIN-102 release from coated-pellets and mini-tablets was reduced in simulated gastric and intestinal fluids. Colitic mice treated with CIN-102 controlled release formulations had less diarrhea and bloody stools. Furthermore, the concentrations of enterobacteria in colonic tissue and stool were significantly reduced in CIN-102 treated mice. These results show that sustained release formulations can effectively deliver CIN-102 in the lower part of the gastrointestinal tract, where the reduction of enterobacteria seems to ameliorate the course of colitis.Conclusion: CIN-102 is novel broad-spectrum antibacterial and sustained release formulations can effectively deliver this agent into the colon, reducing bacterial loads which might influence the state of intestinal inflammation.
270

Saccharomyces boulardii reverte a resposta inflamatÃria e funcional presente na mucosite intestinal induzida por 5-fluorouracil em camundongos. / Saccharomyces boulardii ameliorates the inflammation and gastric dysmotility presents in intestinal mucositis induced by 5-fluorouracil in mice.

Priscilla Fernanda Campos Justino 20 June 2011 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / IntroduÃÃo: A mucosite induzida por antineoplÃsicos à um fator limitante na terapia anticÃncer. O trato gastrintestinal à vulnerÃvel por causa da alta proliferaÃÃo e frequÃncia de renovaÃÃo celular. Saccharomyces boulardii (SB) à uma levedura probiÃtica que à utilizado para proteger a microflora gastrintestinal do desequilÃbrio e de distÃrbios gastrintestinais associados. Objetivos: Avaliar o efeito do tratamento com SB na resposta inflamatÃria e nas alteraÃÃes da motilidade digestiva no curso da mucosite intestinal experimental induzida por 5-FU. MÃtodos: Camundongos machos Swiss (25-30g) foram tratados com 5-FU (450mg/Kg, i.p.) ou com soluÃÃo salina (controle). Outros grupos receberam durante 3 ou 6 dias SB (800mg/Kg, gavagem) atà o dia do sacrifÃcio, diariamente. Um grupo prÃ-tratado recebeu o SB por 3 dias antes e 3 dias depois da administraÃÃo do 5-FU (SB 6D) e outro grupo recebeu SB somente 3 dias apÃs a administraÃÃo do 5-FU (SB 3D). No 3 dia apÃs o 5-FU ou 5-FU+SB (3D ou 6D), os animais foram sacrificados, amostras de jejuno e Ãleo foram retiradas para avaliar a injÃria epitelial por morfometria, escores histolÃgicos, atividade de MPO, nÃveis de nitrito e concentraÃÃo de GSH. Para avaliaÃÃo de citocinas pelo mÃtodo de ELISA foi determinada a concentraÃÃo de IL-1&#946; e CXCL1. Jà na tÃcnica de esvaziamento gÃstrico os animais receberam o mesmo tratamento descrito anteriormente. Posteriormente, foram deixados em jejum de 18 horas. No 7 dia foram administrados 0,3 ml da soluÃÃo glicosada (5%) contendo vermelho de fenol (VF) a 0,75 mg/ml em cada animal. ApÃs 20 min, os animais foram sacrificados e submetidos a uma laparotomia mediana. O intestino delgado foi exposto e divido em 3 partes iguais: proximal, medial e distal. Com o auxÃlio de uma proveta contendo uma soluÃÃo de NaOH (100ml, 0,1N) o volume do estÃmago e dos segmentos do intestino delgado foram determinados. A absorbÃncia da amostra foi lida à 540nm. Resultados: O tratamento com 5-FU foi capaz de induzir uma lesÃo intestinal com um importante comprometimento da barreira epitelial funcional com a presenÃa das seguintes alteraÃÃes: encurtamento acentuado das vilosidades intestinais, necrose parcial de criptas, vacuolizaÃÃo de cÃlulas, presenÃa de infiltrado de polimorfonucleares, produÃÃo de radicais livres com consumo de GSH, aumento dos nÃveis de nitrito, aumento na concentraÃÃo de IL-1&#946; e CXCL1 e alteraÃÃes na motilidade digestiva. O tratamento com SB reduziu significativamente as lesÃes intestinais, com recuperaÃÃo da altura dos vilos, recuperaÃÃo da profundidade das criptas, diminuiÃÃo do infiltrado neutrofÃlico e dos nÃveis de nitrito, aumento dos nÃveis de glutationa e reduÃÃo da concentraÃÃo de IL-1&#946; e CXCL1. Contudo, o tratamento com SB foi capaz de reverter o retarde do esvaziamento gÃstrico e do transito gastrintestinal. ConclusÃo: 5-FU induz mucosite intestinal em camundongos com a participaÃÃo de IL-1&#946; e CXCL1, a qual se associa com retarde no esvaziamento gÃstrico e no transito gastrintestinal. O tratamento com SB foi capaz de reverter os achados inflamatÃrios e as alteraÃÃes na motilidade digestiva associadas à mucosite por 5- FU em camundongos. / Introduction: Intestinal mucositis is a frequent side-effect associated to 5-fluorouracil (5-FU) clinical use and results in inflammatory events. It is characterized by epithelial ulcerations in the mucosa and clinical manifestations of abdominal pain, nauseas and diarrhea. Saccharomyces boulardii is a probiotic yeast which has been shown to protect the gastrointestinal microflora from disequilibrium and from associated gastrointestinal disorders. Aim: To evaluate the effect of treatment with Saccharomyces boulardii in inflammatory response and alterations in the gastrintestinal motility in the course of intestinal mucositis experimental induced by 5-FU. Methods: Swiss male mice (25-30g) were treated with 5-FU (450mg/Kg, ip) or saline (control). Other groups received 3 or 6 days during SB (800mg/Kg, gavage) until the day of sacrifice, every day. A group pretreated received the SB for 3 days before and 3 days after administration of 5-FU (SB 6D) and another group received SB only 3 days after administration of 5-FU (SB 3D). At day 3 after 5-FU, the animals were sacrificed, samples of jejunum and ileum were collected to assess the injury epithelial morphometry, histological scores, the activity of MPO, nitrite levels and the concentration of GSH. For evaluation of cytokine samples of jejunum and ileum were removed and the ELISA was determined concentrations of IL-1&#946; and CXCL1. In the technique of gastric emptying, the animals received the same treatment described above. Later, they were left to fast for 18 hours from d6 to d7. At d7, were administered 0.3 ml of glucose solution (5%) containing phenol red (VF) to 0.75 mg / ml in each animal. After 20 min, the animals were sacrificed and underwent a laparotomy. The small intestine was exposed and divided into 3 equal parts: proximal, medial and distal. With the aid of a beaker containing a solution of NaOH (100ml, 0.1 N) the volume of the stomach and small intestine segments were determined. The sample absorbance was read in a wavelength of 540 nm. Results: Treatment with 5-FU was able to induce intestinal injury with a significant impairment of epithelial barrier function in the presence of the following changes: severe shortening of the villus, crypts of partial necrosis, vacuolization of cells, infiltration and mono polymorphonuclear free radical production with consumption of GSH, increased levels of nitrite, increased concentration of IL-1&#946; and CXCL1 and changes in gastrointestinal motility. Treatment with SB significantly reduced intestinal damage, with recovery of villous height, crypt depth recovery, decreased neutrophil infiltration and nitrite levels, increased levels of glutathione and reduced concentrations of IL-1&#946; and CXCL1. However, treatment with SB was able to reverse the delayed gastric emptying and gastrointestinal transit. Conclusion: 5-FU induces intestinal mucositis in mice involving IL-1&#946; and CXCL1, which is associated with delayed gastric emptying and gastrointestinal transit in. Treatment with SB, both 3D and 6D, were able to reverse the inflammatory changes, and revert the changes in gastrointestinal motility associated with mucositis by 5 - FU in mice.

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