Investigating CD8+ T-cell gene expression signatures as disease prognostic biomarkers in paediatric inflammatory bowel disease.

Background: Currently, it is not possible to predict disease behaviour for children with inflammatory bowel disease (IBD), which is a major obstacle in an era where we strive to deliver personalised, tailored therapy. Previous investigation of gene expression profiles from CD8+ T-cells in adult IBD cohorts identified promising signatures, including a T-cell exhaustion signature, to predict disease outcome in these patients. Hypothesis and aim: We hypothesised that adult CD8+ T-cell prognostic signature and T-cell exhaustion signature would also predict outcome in paediatric IBD. We also hypothesised that CD8+ methylation profiles would underpin changes in gene expression, hence providing an alternative potential predictor. The aim of this project was to test whether CD8+ T-cell gene expression and methylation signatures can predict disease outcome in children with IBD. Methods: Purified CD8+ T-cells from a prospective cohort of 112 children newly diagnosed (treatment naïve) with IBD were subjected to cellular genome-wide RNA and DNA profiling (affymetrix and epic methylation microarrays). Detailed clinical information from each patient was recorded in a clinical database (1.5 years follow-up). First, the adult CD8 prognostic signatures were applied to the paediatric data in order to test for their ability to differentiate children according to their disease behaviour. Subsequently, the paediatric data was analysed on its own through unsupervised clustering analysis and Weighted Gene Co-expression Network Analysis (WGCNA) to test for correlations between gene expression data and clinical outcome parameters. Survival analysis (kaplan meyer) was used to compare patient groups for disease outcomes, including number of treatment escalations, use of biologic treatments and surgical intervention. Results: Applying the adult CD8 prognostic signature and the T-cell exhaustion signature to the paediatric dataset did not generate groups with significant differences in disease outcomes. Furthermore, the clinical data collected from the paediatric cohort showed that two thirds of the children had at least two treatment escalations, compared to less than 40% of the adult patients from the previous study. The analysis of the paediatric data per se identified correlations with clinical outcomes including use of biologics in Crohn’s (WGCNA correlation index (CI) < 0.4) and surgical intervention in ulcerative colitis (top CI: +0.38 and – 0.59). Preliminary analysis of the CD8 methylation profile did not show any correlation with clinical outcomes in this paediatric cohort. Conclusion: The adult prognostic CD8 signatures did not prove to be effective in children with IBD. We speculate that this could be due to the paediatric IBD phenotype being homogeneously more severe. Our findings hint the hypothesis that absent T-cell exhaustion in paediatric CD8+ T-cell could underlie a more severe disease phenotype in children. Further understanding of the mechanism of T-cell exhaustion in children has the potential to open up to future target options in paediatric IBD.CICRA (Crohn's in Childhood Research Association

Peculiarities of Paediatric Digestive Endoscopy

1. Introduction 1.1. What is the role of paediatric endoscopy nowadays? Which are the main indications and contra-indications? An increased knowledge of normal and pathologic endoscopic patterns in paediatric patients has been increasing in the last decades. Besides, the availability of flexible instruments with narrow diameter and elevate qualitative resolution allows Paediatric Gastroenterologists to investigate small infants too. An adequate setting including endoscopic equipment, endoscopic room, support area and dedicated caregivers is fundamental to perform appropriate procedures. Diagnostic endoscopy comprehends fiber-endoscopy, capsule endoscopy, confocal microendoscopy and echo-endoscopy. Roles of Digestive Endoscopy \u2022 Visualisation of the mucosa; \u2022 Evaluation of architecture and vascularisation; \u2022 Evaluation of mucosal secretions; \u2022 Availability to take biopsy samples for histological examination with optic microscopy, ultra-structural examination with electronic microscopy, cultures, CRP methods, dissecting microscopy, chromo-endoscopy, vital staining, enzymatic studies, brushing; \u2022 Endoscopic treatments. Functions of Digestive Endoscopy \ua9 2013 Gasparetto and Guariso; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. \u2022 Morphologic diagnosis of structural congenital and acquired alterations (optic microscopy, immune-histochemistry, electronic microscopy, confocal microendoscopy, brushing); \u2022 Identification of infective processes (CRP techniques of molecular biology) and cultural examination; \u2022 Morphological, chemical and microbiological evaluation of endoluminal secretions; \u2022 Endoscopic treatment in case of gastrointestinal bleeding, varices, polyps, stenoses, tumors. Appropriateness. Indications and contraindications to endoscopic examinations [1-2] An endoscopic exam is indicated when the expected benefits (longer life survival, pain contention, reduction of anxiety, increase in functional capacity) exceed the potential negative consequences (mortality, morbidity, anxiety, pain, disability). An endoscopic exam is necessary when it is unavoidable and mandatory for the care of the patient. Signs and Symptoms of Indication for Upper Gastrointestinal (GI) Endoscopy \u2022 GI bleeding; \u2022 Disphagia, odinophagia, persistent feeding refusal, persistent chest pain; \u2022 Upper abdominal pain with signs and symptoms suggesting organic diseases (red flags); \u2022 Suspect of peptic disease; \u2022 Persistent vomit; \u2022 Suspected alterations at upper GI imaging; \u2022 Suspected caustic ingestion; \u2022 Iron deficiency anaemia. Pathologic Conditions for which Diagnostic Upper GI Endoscopy is indicated: \u2022 Peptic esophagitis, hemorrhagic gastritis, peptic ulcers in stomach, bulbus and duodenum; \u2022 Gastrointestinal opportunistic infections i.e. Cytomegalovirus, Fungi; \u2022 Eosinophilic esophagitis; \u2022 Caustic ingestion; \u2022 Atrophic gastritis; \u2022 Helicobacter pylori (HP) gastritis; \u2022 Coeliac disease; \u2022 Inflammatory bowel disease (IBD) with localisation at the upper GI tract; 268 Endoscopy of GI Tract \u2022 Patients with liver cirrhosis, disphagia, malnutrition, oesophageal varices; \u2022 Congestive gastropathy; \u2022 Chronic diarrhoea of unknown nature; \u2022 Structural alteration of the mucosa (Microvillus Inclusion Disease, Tufting Enteropathy); \u2022 Benign or malignant lesions in common bile duct or duodenum; \u2022 Graft Versus Host Disease (GVHD) after bone marrow transplantation; \u2022 Lymphoproliferation after organ transplantation i.e. EBV-related gastric lymphoma after liver transplantation. Pathologic Conditions for which Therapeutic Upper GI Endoscopy is indicated: \u2022 Polypectomy; \u2022 Treatment of oesophageal varices; \u2022 Placement of ostomies; \u2022 Treatment of GI bleeding (i.e. bleeding ulcers) non responsive to medical therapy; \u2022 Removal of foreign bodies; \u2022 Oesophageal stricture. Absolute Contraindication to Upper GI Endoscopy \u2022 Suspect of Gastrointestinal Perforation. Relative Contraindications to Upper GI Endoscopy \u2022 Non complicated gastro-oesophageal reflux; \u2022 Functional uncomplicated abdominal pain; \u2022 Congenital hypertrophic stenosis of the pylorus; \u2022 Isolated spasm of the pylorus; \u2022 Follow-up controls for ulcers, mucosal abnormalities, Barrett oesophagus; \u2022 Surveillance of benign healed lesions. Upper GI endoscopy is not appropriate for all children with dyspeptic symptoms, but only for cases [3]: \u2022 With a family history of peptic ulcer and/or HP infection; \u2022 Over 10 years of age; \u2022 With symptoms persisting for more than 6 months; \u2022 With symptoms severe enough to affect activities of daily living; Peculiarities of Paediatric Digestive Endoscopy http://dx.doi.org/10.5772/52523 269 Pathologic Conditions for which Diagnostic Lower GI Endoscopy is indicated: \u2022 Inflammatory bowel disease (IBD); \u2022 Infective colitis; \u2022 Allergic colitis; \u2022 Neutrophil disfunction associated colitis i.e. Glycogenosis; \u2022 Immune mediated diseases; \u2022 Vascular abnormalities (venous ectasia secondary to portal hypertension, angiodysplasia, haemangiomas, vasculitis); \u2022 Polyps and polyposes (juvenile polyps, adenomatous polyps, hyperplastic polyps, hamartomatous polyps, hereditary polyposic syndromes as Peutz-Jeghers Syndrome, Cowden Syndrome); \u2022 Pseudopolyps of the colon; \u2022 Neoplastic lesions i.e. leiomyosarcoma, lymphoma, carcinoma; \u2022 Screening of displasia; \u2022 Surveillance after bowel transplantation (rejection, complications); \u2022 Obscure iron deficient anaemia; \u2022 Structural alteration of the mucosa (Microvillus inclusion disease, Tufting enteropathy); \u2022 Chronic diarrhoea of unknown nature; \u2022 Suspect of filling defects or stenoses at radiographic-ultrasonographic images; \u2022 Rectal trauma; \u2022 Necessity of ileal or colonic bioptic samples. Pathologic Conditions for which Therapeutic Lower GI Endoscopy is indicated: \u2022 Polypectomy; \u2022 Post-polypectomy complications; \u2022 Mucosal resections; \u2022 Ablation of vascular malformations (i.e. Dieulafoy Lesion); \u2022 GI bleeding (i.e. Bleeding ulcers); \u2022 Placement of percutaneous ostomies; \u2022 Dilatations of colonic stenoses; \u2022 Removal of foreign bodies; Absolute Contraindications to Lower GI Endoscopy 270 Endoscopy of GI Tract \u2022 Suspected intestinal perforation; \u2022 Severe acute colitis with toxic megacolon; Relative Contraindications to Lower GI Endoscopy \u2022 Acute self-limiting diarrhoea; \u2022 Gastrointestinal bleeding with demonstrated origin at the upper GI tract; \u2022 Recent intestinal resection; \u2022 Irritable bowel syndrome; \u2022 Chronic abdominal pain without significant morbidity; \u2022 Simple constipation and encopresis

Highlights in IBD Epidemiology and Its Natural History in the Paediatric Age.

Background. The number of patients of all age brackets diagnosed with Inflammatory Bowel Disease (IBD) has risen dramatically worldwide over the past 50 years. IBD's changing epidemiology suggests that environmental factors play a major role in modifying disease expression. Aim. To review studies carried out worldwide analyzing IBD epidemiology. Methods. A Medline search indicating as keywords "Inflammatory Bowel Disease," "epidemiology," "natural history," "Crohn's Disease," "Ulcerative Colitis," and "IBD Unclassified" was performed. A selection of clinical cohort and systematic review studies that were carried out between 2002 and 2013 was reviewed. Studies referring to an earlier date were also considered whenever the data were relevant to our review. Results. The current mean prevalence of IBD in the total population of Western countries is estimated at 1/1,000. The highest prevalence and incidence rates of IBD worldwide are reported from Canada. Just as urbanization and socioeconomic development, the incidence of IBD is rising in China. Conclusions. Multicenter national registers and international networks can provide information on IBD epidemiology and lead to hypotheses about its causes and possible management strategies. The rising trend in the disease's incidence in developing nations suggests that its epidemiological evolution is linked to industrialization and modern Westernized lifestyles

Treating children with inflammatory bowel disease: Current and new perspectives.

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gut characterised by alternating periods of remission and relapse. Whilst the mechanism underlying this disease is yet to be fully understood, old and newer generation treatments can only target selected pathways of this complex inflammatory process. This narrative review aims to provide an update on the most recent advances in treatment of paediatric IBD. A MEDLINE search was conducted using "paediatric inflammatory bowel disease", "paediatric Crohn's disease", "paediatric ulcerative colitis", "treatment", "therapy", "immunosuppressant", "biologic", "monitoring" and "biomarkers" as key words. Clinical trials, systematic reviews, and meta-analyses published between 2014 and 2016 were selected. Studies referring to earlier periods were also considered in case the data was relevant to our scope. Major advances have been achieved in monitoring the individual metabolism, toxicity and response to relevant medications in IBD including thiopurines and biologics. New biologics acting on novel mechanisms such as selective interference with lymphocyte trafficking are emerging treatment options. Current research is investing in the development of reliable prognostic biomarkers, aiming to move towards personalised treatments targeted to individual patients

The multidisciplinary health care team in the management of stenosis in Crohn's disease.

BACKGROUND: Stricture formation is a common complication of Crohn's disease (CD), occurring in approximately one-third of all patients with this condition. Our aim was to summarize the available epidemiology data on strictures in patients with CD, to outline the principal evidence on diagnostic imaging, and to provide an overview of the current knowledge on treatment strategies, including surgical and endoscopic options. Overall, the unifying theme of this narrative review is the multidisciplinary approach in the clinical management of patients with stricturing CD. METHODS: A Medline search was performed, using "Inflammatory Bowel Disease", "stricture", "Crohn's Disease", "Ulcerative Colitis", "endoscopic balloon dilatation" and "strictureplasty" as keywords. A selection of clinical cohort studies and systematic reviews were reviewed. RESULTS: Strictures in CD are described as either inflammatory or fibrotic. They can occur de novo, at sites of bowel anastomosis or in the ileal pouch. CD-related strictures generally show a poor response to medical therapies, and surgical bowel resection or surgical strictureplasty are often required. Over the last three decades, the potential role of endoscopic balloon dilatation has grown in importance, and nowadays this technique is a valid option, complementary to surgery. CONCLUSION: Patients with stricturing CD require complex clinical management, which benefits from a multidisciplinary approach: gastroenterologists, pediatricians, radiologists, surgeons, specialist nurses, and dieticians are among the health care providers involved in supporting these patients throughout diagnosis, prevention of complications, and treatment

Comparison of Model Order Reduction Techniques for Flexible Multibody Dynamics using an Equivalent Rigid-Link System Approach

In this paper we present a comparison of different model order reduction techniques for flexible multibody dynamics. In particular, we adopt a formulation based on a Equivalent Rigid-Link System (ERLS). This approach is suitable in the case of large displacements and small elastic deformations and it allows the kinematic equations of motion to be decoupled from the compatibility equations of the displacements at the joints. The ERLS approach, recently extended through a modal formulation, is here implemented in combination with different reduction techniques, i.e. Craig- Bampton, Interior Mode Ranking (IMR), Guyan, Least Square Model Reduction (LSMR) and Mode Displacement Method (MDM). In order to assess the advantages and disadvantages of the different methodologies, these techniques are applied to a benchmark mechanism under different input conditions, i.e. gravitational force and step torque input. The accuracy of each reduced model is numerically evaluated through the comparison of computational time, the behaviour in frequency domain and by means of vector correlation methods, i.e. the Modal Assurance Criterion (MAC), the Cross-Orthogonality (CO) and the Normalized Cross-Orthogonality (NCO)

CONFRONTO TRA METRICHE PER LA VALUTAZIONE DEL DISTURBO DERIVANTE DALLE VIBRAZIONI NEGLI EDIFICI - METRICS COMPARISON FOR THE EVALUATION OF THE ANNOYANCE DUE TO VIBRATIONS IN BUILDINGS

L’articolo descrive l’analisi comparativa tra le metriche per la valutazione del disturbo descritte dalla norma UNI 9614:1990 e dalla ISO 2631-2:2003. La norma ISO 2631-2:2003 introduce una modalità di valutazione diversa basata su curva di ponderazione Wm e con calcolo del valore efficace secondo la norma ISO 8041:2005. Gli indici di valutazione del disturbo sono stati confrontati in diverse condizioni sperimentali: vibrazioni in edifici civili derivante da sorgenti stazionarie o non stazionarie originate da traffico ferrotramviario e macchinari. I risultati mostrano come le differenze tra i diversi metodi siano in genere trascurabili se confrontate alla variabilità dei fenomeni in esame

Modeling the vibration of spatial flexible mechanisms through an equivalent rigid-link system/component mode synthesis approach

In this paper, a novel formulation for modeling the vibration of spatial flexible mechanisms and robots is introduced. The formulation is based on the concepts of equivalent rigid-link system (ERLS) that allows kinematic equations of motion for the ERLS decoupled from the compatibility equations of the displacement at the joint to be written. With respect to the available literature, in which the ERLS concept has been proposed together with a finite element method (FEM) approach (ERLS-FEM), the formulation is extended in this paper through a modal approach and, in particular, a component mode synthesis technique which allows a reduced-order system of dynamic equations to be maintained even when a fine discretization is needed. The model is validated numerically by comparing it with the results obtained from the Adams-Flex\u2122 software, which implements the well-known floating frame of reference approach for a benchmark L-shaped mechanism. A good agreement between the two models is shown