117,345 research outputs found
Virtual endoscopy of the middle and inner ear with spiral computed tomography. Neri E, Caramella D, Battolla L, Cosottini M, Scasso CA, Bruschini P, Pingitore R, Bartolozzi C
No full textDigital radiology with storage phosphors in cephalometric study in orthodontics
No full textConventional radiology is continually modified with the development of digital systems which can be used for several types of radiologic examinations. Our study was aimed at evaluating the advantages of these new technologies in the orthodontic field, where the problems associated with image quality and radiation protection are major especially in young patients; the latter goal is achievable by dramatically reducing radiation dose and by avoiding repeating the exam. In our study, we compared lateral teleradiographs of the skull for cephalometric analysis obtained using conventional and digital diagnostic methods. The preliminary results demonstrated that the two imaging techniques did not differ relative to bone structure representation, even though the digital system provided better visualization of soft tissue structures. Computed radiography also allowed a marked reduction in the number of repeats and reduced radiation dose. The current disadvantages of this imaging method are the high initial cost of the equipment, reduced work rate, and the need of frequent technical assistance
Thymus alterations and systemic sclerosis
No full textOBJECTIVES: The pathogenesis of systemic sclerosis (SSc) includes complex alterations to the immune system, possibly responsible for diffuse microvasculature and fibroblast dysfunction. Previous anecdotal observations suggest a possible role for thymus alterations in some autoimmune rheumatic diseases, including SSc. This study aimed to investigate the prevalence of radiological thymus alterations in SSc patients. METHODS: Thirthy-four unselected patients [28 female and 6 male, mean age (+/- S.D.) 49.7 +/- 9.5 yr, range 33-67 yr] and 34 age- and sex-matched controls were included in the study. The presence of major radiological thymus alterations, i.e. an abnormally enlarged or nodular thymus, were blindly investigated by means of unenhanced multidetector computed tomography. RESULTS: Abnormally enlarged or nodular thymuses were detected in a statistically significant percentage of SSc patients compared with controls (21 vs 0%, P = 0.011). More interestingly, radiological thymus alterations were invariably observed in patients with shorter disease duration (< or =5 yr, 41% vs >5 yr, 0%; P = 0.007), frequently associated with serum anti-Scl70 antibodies (P = 0.017). Among patients with thymus alterations one developed myasthenia gravis while two others showed thymus hyperplasia at histopathological evaluation after thymectomy. CONCLUSIONS: The present study suggests a possible role of thymic disorders, mainly thymus hyperplasia, in a significant number of SSc patients. Due to the limitations of radiological evaluation, the actual relevance of such an association might be underestimated. The relationship of thymus alterations with shorter disease duration, as well as with serum anti-Scl70, suggests that thymic dysfunction could play a pathogenetic role mostly in the early phases of the disease, and possibly in specific SSc patient subsets
IL TRAPIANTO DEL PANCREAS: ESPERINZA PRELIMINARE NEL FOLLOW-UP POSTOPERATORIO CON TC MULTIDETETTORE
No full textCLISMA A DOPPIO CONTRASTO E COLOGRAFIA TC A CONFRONTO NELLO STUDIO DEL CARCINOMA COLORETTALE
No full textCT versus MRI in the differentiation of benign from malignant pleural disease [Confronto fra tomografia computerizzata e risonanza magnetica nella valutazione delle malattie pleuriche benigne e maligne].
No full textTo compare the diagnostic capabilities of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) in differentiating benign from malignant pleural disease, we examined with MRI at 0.5 T forty-five patients with pleural lesions identified on CT scans. For 34 patients, a final diagnosis of malignant (n = 18) or benign (n = 16) disease was made. T1, proton density/T2 and enhanced T1-weighted spin-echo images were acquired. CT and MR images were independently studied by two observers, who were unaware of the final diagnosis. Various morphological features suggesting benign or malignant pleural disease were evaluated. On the basis of the morphological CT features, a final diagnosis of benignity of malignancy was expressed in terms of two different levels of confidence - probable or definitive. The MR signal intensity of pleural lesions was compared with that of intercostal muscles (isohypointense or hyperintense). No significant differences were observed between CT and MR morphological findings. High signal intensity on proton density/T2-weighted images was observed in all malignant lesions and in 2 benign lesions (100% sensitivity, 87% specificity). In the absence of this sign (i.e., isointense or hypointense signal), the lesions were always benign (100% negative predictive value). All the definitive CT diagnoses were correct, while 6 of 17 probable CT diagnoses were incorrect. In the subgroup of lesions misinterpreted with CT, MR signal intensity on long-TR images always allowed the correct differentiation of benign from malignant conditions. To conclude, MR signal intensity is a valuable additional feature to differentiate benign from malignant pleural disease. We suggest the use of MRI in the pleural lesions where the level of confidence of CT diagnosis is low
Embedding methods for poly(L-lactic acid) microfiber mesh/human mesenchymal stem cell constructs
No full textFiber mesh scaffolds were recently investigated in tissue engineering as possible support for stem cell growth and differentiation, in order to repair lesion areas in clinical practice. In particular, the literature is focused on fiber mesh scaffolds constituted of biocompatible and resorbable polymeric structures, like poly(L-lactic acid) (PLLA). However, as regards the study of constructs constituted of PLLA microfibers and cells, only quantitative and SEM analyses were reported, lacking histological analysis. Histological evaluation of these constructs could give important information about cellular distribution in the scaffold, cell-scaffold interactions and extracellular matrix production. The purpose of our study was to find a valid method to analyze PLLA microfiber/cell constructs from both histological and histochemical angles. Biodegradable non-woven fiber meshes were prepared using hollow microfibers, based on PLLA. We first evaluated different embedding methods useable for histological analysis and the results showed that among the paraffin, Killik, and acrylic resin the only suitable medium was the latter. Then we employed the acrylic resin to embed the constructs made up of PLLA microfibers and bone marrow-derived human mesenchymal stromal cells, which we then analyzed with Toluidine Blue, PAS and Alcian Blue staining. These constructs, previously analyzed for cell viability by MTT and CCK-8 tests, showed viable/proliferating cells until 6 weeks of culture. The stainings performed on constructs confirmed viability data obtained with SEM and MTT/CCK-8 and supplied other information on the cell behaviors such as the distribution and organization onto the scaffold and the production of extracellular matrix molecules. In conclusion, this methodological study mainly suggests a suitable method to analyze PLLA microfiber/cell constructs, at the same time confirming and enriching the literature data on the compatibility between PLLA microfibers and hMSCs
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