456 research outputs found
Regulation of the T helper cell type 1 transcription factor T-bet in coeliac disease mucosa
No full textBackground: In coeliac disease ( CD) mucosa, the histological lesion is associated with marked infiltration of T helper cell type 1 (Th1) cells. However, the molecular mechanisms which regulate Th1 cell differentiation in CD mucosa are unknown. Aims: To analyse expression of transcription factors which control the Th1 cell commitment in CD. Patients: Duodenal mucosal samples were taken from untreated CD patients and normal controls. Methods: Interferon gamma (IFN-gamma) and interleukin (IL)-4 RNA expression was examined in T lamina propria lymphocytes by quantitative reverse transcription-polymerase chain reaction. T-bet and STAT-4, two Th1 promoting transcription factors, and STAT-6 and GATA-3, transcription factors which govern T helper cell type 2 (Th2) cell polarisation, were examined in duodenal biopsies by western blotting. The effect of gliadin and IFN-gamma on expression of T-bet was examined in an ex vivo culture of biopsies taken from normal and treated CD patients. Results: As expected, IFN-gamma but not IL-4 RNA transcripts were increased in the mucosa of CD patients in comparison with controls. CD mucosal samples consistently exhibited higher levels of T-bet than controls. However, no difference in active STAT-4 expression was seen between CD patients and controls, suggesting that Th1 polarisation was not induced by local IL-12. GATA-3 and STAT-6 were also low in both CD and control mucosa. In normal duodenal biopsies, IFN-gamma stimulated T-bet through a STAT-1 dependent mechanism. Challenge of treated CD but not control biopsies with gliadin enhanced T-bet and this effect was also inhibited by STAT-1 inhibition. Conclusions: This study shows that activation of STAT-1 by IFN-gamma promotes T-bet in CD mucosa
INFLIXIMAB FOR PEDIATRIC ULCERATIVE COLITIS:A RETROSPECTIVE ITALIAN MULTICENTER STUDY
No full text. Dig Liver Dis. 2008 Jul;40 Suppl 2:S260-4.
Infliximab for pediatric ulcerative colitis: a retrospective Italian multicenter
study.
Cucchiara S, Romeo E, Viola F, Cottone M, Fontana M, Lombardi G, Rutigliano V,
de'Angelis GL, Federici T.
Division Pediatric Gastroenterology and Hepatology, Department of Pediatrics,
University of Rome "La Sapienza", Rome, Italy. [email protected]
BACKGROUND: Infliximab (IFX), the chimeric anti TNFalpha antibody, an established
treatment for Crohn's disease in adults and in children, is used less frequently
in ulcerative colitis (UC).
AIM OF THE STUDY: To report the clinical course of pediatric patients with active
UC receiving IFX.
PATIENTS AND METHODS: Charts of 22 patients were reviewed (13 male, 9 female): 4
with a severe UC attack refractory to systemic corticosteroids (CS); 18 with a
protracted course, of which 16 CS-dependent and 2 CS-resistant. The baseline
therapeutic program consisted of 3 consecutive intravenous infusions (0, 2, 6
weeks) of IFX (5 mg/kg), followed by a retreatment schedule (infusion every 8
weeks); azathioprine (AZA) was administered chronically in all. Clinical
evaluation was done with the Lichtiger Colitis Activity Index (LCAI). Follow-up
was performed until week 54. LCAI >/= 9 was considered treatment failure; a LCAI
</= 2 was consistent with remission.
RESULTS: All 22 patients began the study with a LCAI > 9: 12 had a full response
and were on remission at week 54 and did not receive CS (8 on IFX re-treatment
and AZA, 4 on AZA alone); 6 had a partial response; 4 were non responders.
Colectomy was performed in 7 patients, beyond the period of the acute attack in
all but one.
CONCLUSIONS: In children with severe ulcerative colitis IFX is a valuable
treatment for inducing remission, avoiding emergency colectomy; retreatment may
be offered to maintain remission
Load Carrying Capacity of Glass Columns with Rectangular, T and X Transverse Cross-sections
No full textIn this study, the load carrying capacities of glass columns with rectangular, T and X cross-sections having different lengths
were calculated. The proposed analytical procedure allows to calculate the load carrying capacity associated with strength of
transverse cross-section including local and global flexural and/or torsional buckling phenomenon. Moreover, initial imperfections
and time dependant effects, the latter associated with the viscoelastic behaviour of interlayer (PVB), were included in the model as
suggested in the literature. Those effects were calculated by introducing the equivalent thickness of glass panels, which takes into
account the shear modulus of PVB and the viscoleastic behaviour of a composite. Failure of the glass panels connected with
structural silicone was not considered. Experimental research recently conducted by the authors was utilised for comparison with
the analytical prediction. Cases of study were those of compressed glass panels constituted by single tempered glass jointed between
PVB, and compressed members having T or X tranverse cross-sections and constituted by single layered panels jointed between
structural silicone. The analytical model had good prediction accuracy, and the experimental results were in agreement with the
failure modes observed experimentall
T_PARK: Ambient Intelligence for Security in Public Parks
No full textIn this paper, we present joint research activities in computer vision and sensor networks for a distributedsurveillance of urban parks. Distributed visual surveillance of urban environments is one of the most interesting scenarios in Ambient Intelligence; in addition, the automated monitoring of public parks, often crowded by children and aduits, is still a very difficult task due to the number of objects of interests. In this context, integrating the power of low cost sensors with the information provided by cameras can lead to a more reliable solution to people tracking in wide areas. Specifically, the deficiencies of one approach can be (at least partially) covered by the advantages of the other. The goal is to perform people tracking in parks (toachieve trackable parks - T-Parks), both in zones covered by overlapped cameras and afso, thanks to sensors, in areas not covered by any camera. In this paper, we propose a new technique for multi-camera people tracking based on a learning phase to automatically calibrate pairs of cameras and to build Areas of Field Views (AoFoVs) in order to establish consistent labelling of people. In addition, sensornetworks distributed at the borders of the AoFoV give an estimation of the probability of people overlapping, triggering specific algorithms of face detection or headcounting to identify the single person. The research ofT-Parks is part of a two-year Italian project called LAICA, intended to provide advanced services for citizens and public officers based on ambient intelligence technologies
How to Choose Pretrained Handwriting Recognition Models for Single Writer Fine-Tuning
No full textRecent advancements in Deep Learning-based Handwritten Text Recognition (HTR) have led to models with remarkable performance on both modern and historical manuscripts in large benchmark datasets. Nonetheless, those models struggle to obtain the same performance when applied to manuscripts with peculiar characteristics, such as language, paper support, ink, and author handwriting. This issue is very relevant for valuable but small collections of documents preserved in historical archives, for which obtaining sufficient annotated training data is costly or, in some cases, unfeasible. To overcome this challenge, a possible solution is to pretrain HTR models on large datasets and then fine-tune them on small single-author collections. In this paper, we take into account large, real benchmark datasets and synthetic ones obtained with a styled Handwritten Text Generation model. Through extensive experimental analysis, also considering the amount of fine-tuning lines, we give a quantitative indication of the most relevant characteristics of such data for obtaining an HTR model able to effectively transcribe manuscripts in small collections with as little as five real fine-tuning lines
Reconfiguring the boundaries of a mesh-connected array of processors with run-time programmable logic
No full textFine grain mesh-connected arrays of processors with a SIMD architecture are considered an attractive solution for many important and emerging real-time data handling applications that require high speed processing of dynamic data sampled over a bidimensional region. Nevertheless, even if the interconnections between the arrays' adjacent nodes are well suited to those applications that may be handled by neighbour based algorithms, the SIMD computational model is, in general terms, still not flexible. Furthermore, the limited size of economically viable arrays calls for a severe overhead in data transfer and array boundary data handling that may impair the system's efficiency. Without modifying the arrays' internal structure, most algorithms could overcome some of their implementation drawbacks with a flexible, fast switching facility on the array boundary. This article presents a 'boundary processor' based on programmable gate arrays whose aim is to dynamically activate the required boundary interconnection pattern either under software control or through an on-line hardware reconfiguration facility. The device has been designed and implemented at the University of Bologna as part of a computer vision machine for robotic applications. © 1993
Processing of variable size images on a cellular array: Performance analysis with the Abingdon Cross Benchmark
No full textHandling a continuous flow of variable size images is a requirement for real time computer vision machines. A modular system based on a small size SIMD cellular array of 1-bit processing elements has been developed with this goal in mind and it is now evaluated against the Abingdon Cross Benchmark specifications. The benchmark tests the combination of algorithms and architecture and generates a quality factor expressed as the ratio of the image lateral size and the processing time. The examined machine supports an efficient means to automatically partition, process and reconstruct images larger than the array size. The authors briefly describe the system, discuss the selected algorithms and present performance results and estimates for several system configurations
An image analysis approach for automatically re-orienteering CT images for dental implants
No full textIn the last decade, computerized tomography (CT) has become the most frequently used imaging modality to obtain a correct pre-operative implant planning. In this work, we present an image analysis and computer vision approach able to identify, from the reconstructed 3D data set, the optimal cutting plane specific to each implant to be planned, in order to obtain the best view of the implant site and to have correct measures. If the patient requires more implants, different cutting planes are automatically identified, and the axial and cross-sectional images can be re-oriented accordingly to each of them. In the paper, we describe the defined algorithms in order to recognize 3D markers (each one aligned with a missed tooth for which an implant has to be planned) in the 3D reconstructed space, and the results in processing red] exams, in terms of effectiveness and precision and reproducibility of the measure
The GIOTTO system: A parallel computer for image processing
No full textThis paper presents the GIOTTO system, a parallel computer based on a scalable single instruction, multiple data (SIMD) array of processors specially conceived for image processing. The system is characterized by a reduced-size array and a novel organization of the memory subsystem, designed to support transparent processing of images larger than the array. The system is designed to meet the computational requirements of machine vision, together with the compactness, ease of integration and flexibility called for by industrial robotic environments. The paper describes the system architecture in detail, focusing on original solutions conceived to endow the system with flexibility and performance. As proof of GIOTTO's suitability for robotic application, its use in a robot vision experiment is presented, showing the approach to the vision problem, the parallel algorithms, and performance analysis. © 1997 Academic Press Limited
- …
