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ABSTRACT: We analyzed magnetic resonance imaging (MRI) morphologic patterns of retroperitoneal fibrosis (RF) to identify those able to distinguish malignant RF (mRF) from idiopathic RF (iRF). This retrospective study concerned 50 consecutive patients with MRI-based RF diagnoses, 35 of whom also had histologically proven RF. Previous radiotherapy, abdominal or pelvic surgery or infection during the preceding 6 months, vascular aneurysm (aorta or iliac artery), presence of retroperitoneal multiple nodular masses, or enlarged lymph nodes with a diameter >15 mm constituted exclusion criteria.Patients with mRF differed from those with iRF by age, smoking habits, and follow-up duration but not by clinical manifestations, inflammatory syndrome, or renal insufficiency. MRI-documented mRF extension along the aorta, from above the renal arteries to below the aortic bifurcation, was more frequent than iRF (47% vs. 0%; p = 0.001) but less frequent between the renal arteries and the aortic bifurcation (18% vs. 50%; p = 0.04); mRF extension behind the aorta was wider than iRF (5.0 vs. 2.5 mm; p = 0.03). Neither urinary tract nor vessel involvement differed. Medial ureteral attraction was significantly less frequent in mRF than iRF (24% vs. 83%; p < 0.001), according to univariate and multivariate analyses. An algorithm based on the most discriminant criteria (RF extending from above the renal arteries to below the aortic bifurcation and the absence of medial ureteral attraction) for mRF diagnosis had 82% sensitivity and 83% specificity. When applied to the 15 iRF patients without histologic data, specificity was 73%.This mRF decision tree, consisting of the 2 most discriminant MRI criteria, could be used as a supplementary argument to support RF biopsy.  相似文献   
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Genetic polymorphisms near IL28B are associated with spontaneous and treatment-induced clearance of hepatitis C virus (HCV), two processes that require the appropriate activation of the host immune responses. Intrahepatic inflammation is believed to mirror such activation, but its relationship with IL28B polymorphisms has yet to be fully appreciated. We analyzed the association of IL28B polymorphisms with histological and follow-up features in 2335 chronically HCV-infected Caucasian patients. Assessable phenotypes before any antiviral treatment included necroinflammatory activity (n = 1,098), fibrosis (n = 1,527), fibrosis progression rate (n = 1,312), and hepatocellular carcinoma development (n = 1,915). Associations of alleles with the phenotypes were evaluated by univariate analysis and multivariate logistic regression, accounting for all relevant covariates. The rare G allele at IL28B marker rs8099917-previously shown to be at risk of treatment failure-was associated with lower activity (P = 0.04), lower fibrosis (P = 0.02) with a trend toward lower fibrosis progression rate (P = 0.06). When stratified according to HCV genotype, most significant associations were observed in patients infected with non-1 genotypes (P = 0.003 for activity, P = 0.001 for fibrosis, and P = 0.02 for fibrosis progression rate), where the odds ratio of having necroinflammation or rapid fibrosis progression for patients with IL28B genotypes TG or GG versus TT were 0.48 (95% confidence intervals 0.30-0.78) and 0.56 (0.35-0.92), respectively. IL28B polymorphisms were not predictive of the development of hepatocellular carcinoma. CONCLUSION: In chronic hepatitis C, IL28B variants associated with poor response to interferon therapy may predict slower fibrosis progression, especially in patients infected with non-1 HCV genotypes.  相似文献   
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Churg-Strauss syndrome (CSS) is a multisystem disorder characterised by asthma, prominent peripheral blood eosinophilia, and vasculitis signs. We report the case of a 22 year-old man admitted to the intensive care unit for acute myocarditis complicated with cardiogenic shock. Eosinophilia, history of asthma, lung infiltrates, paranasal sinusitis, glomerulonephritis, and abdominal pain suggested the diagnosis of CSS. Cardiac MRI confirmed cardiac involvement with a diffuse subendocardial delayed enhancement of the left ventricular wall, and a left ventricular ejection fraction (LVEF) of 30%. Acute myocarditis was confirmed with myocardial biopsy. The patient was successfully treated with systemic corticosteroids, intravenous cyclophosphamide, vasopressor inotropes, intra-aortic balloon pump and mechanical ventilation, and was discharged 21 days later. One year after diagnosis, the patient was asymptomatic. The eosinophilic cell count was normal. Follow-up MRI at one year showed LVEF of 40% with persistent delayed enhancement. Cardiac involvement by CSS requires immediate therapy with corticosteroids and cyclophosphamide, which may allow recovery of the cardiac function.  相似文献   
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Stem cells discovery and their potential have led to the emergence of new forms of therapy with the development of bio-engineering cell and tissue methods underlying future medicine. The availability of stem cells and their preservation thus become an issue for everyone's health. Among the different sources of stem cells, those in the dental pulp have the advantage of being pluripotent, they can be cryopreserved and stored for long periods without losing their multiplication and differentiation capacities and finally they are easily accessible. The wisdom or natal teeth extracted for medical reasons are an opportunity for everyone to preserve stem cells for an autologous use. Biobanks authorized and specialized in the preparation and storage of pulp stem cells provide access to autologous regenerative medicine of tomorrow.  相似文献   
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Percutaneous radiologic gastrostomy (PRG) requires preliminary gastric inflation through a nasogastric tube (NGT) to safely perform gastric puncture. However, in case of pharyngeal or esophageal obstruction, NGT placement may be impossible even with a hydrophilic angiography catheter and wire. This brief report describes percutaneous computed tomography (CT)–guided gastrostomy with a 2-stick approach without nasogastric insufflation in 13 patients. Technical success rate was 100% with a mean of 1.8 punctures ± 1.0 to access the gastric lumen. Traversal of the colon and liver with a 22-gauge needle was necessary in 4 and 1 patients, respectively. There were no major complications. Minor complications occurred in 6 patients (46%). CT-guided percutaneous gastrostomy is technically feasible with minimal morbidity.  相似文献   
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Bone infections are difficult to treat and can lead to severe tissue destruction. Acute bone infections are usually caused by Staphylococcus aureus. Osteoclasts, which belong to the monocyte/macrophage lineage, are the key cells in bone infections. They are not well equipped for killing bacteria and may serve as a reservoir for bacterial pathogens. Silver has been known for centuries for its bactericidal activity. Here, we investigated the bactericidal effects of nano-silver particles in bacteria infected human osteoclasts. We found that nano-silver in per se non-toxic concentration enhanced the bactericidal activity in osteoclasts against intracellular Methicillin-resistant, virulent Staphylococcus aureus. The reduced bacterial survival in nano-silver pretreated cells correlated with increased reactive oxygen responses towards the invading pathogens. Overall, these results indicate that nano-silver compounds should be considered as an effective treatment and prevention option for bacterial bone and orthopedic implant infections.  相似文献   
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