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81.
82.
Effect of hepatitis B and C virus infections on the natural history of compensated cirrhosis: a cohort study of 297 patients 总被引:10,自引:0,他引:10
Fattovich G Pantalena M Zagni I Realdi G Schalm SW Christensen E;European Concerted Action on Viral Hepatitis 《The American journal of gastroenterology》2002,97(11):2886-2895
OBJECTIVES: The aim of this study was to compare the prognosis of patients with hepatitis B surface antigen (HBsAg) positive and those with antibody to hepatitis C (anti-HCV) positive cirrhosis. METHODS: This was a retrospective cohort study of 297 untreated Western European patients with compensated viral cirrhosis (Child class A; 161 patients with hepatitis type B and 136 with type C) who were followed for a median period of 6.6 yr. RESULTS: At diagnosis, median age was lower (48 vs 58 yr, respectively) in HBsAg-positive cirrhotic patients. The Kaplan-Meier 5-yr probability of hepatocellular carcinoma (HCC) was 9% and 10% in HBsAg and anti-HCV-positive cirrhotic patients, respectively; the corresponding figures for decompensation unrelated to HCC were 16% and 28% and for survival were 86% and 84%, respectively. After adjustment for clinical and serological differences at baseline, the relative risk (95% CI) for HCC, decompensation and mortality was 1.53 (CI = 0.81-2.89), 0.59 (CI = 0.37-0.94), and 1.44 (CI = 0.85-2.46) respectively, in HBsAg-positive patients compared with anti-HCV-positive cirrhotic patients. Among HBsAg-positive cirrhotic patients, the relative risk for HCC, decompensation, and mortality was 0.89 (CI = 0.30-2.63), 4.05 (CI = 1.09-15.1), and 5.9 (CI = 1.64-21.3), respectively, in HBV-DNA positive (HBeAg positive or negative) compared with HBV-DNA negative (HBeAg negative) patients at entry. CONCLUSIONS: Patients with HBV infection may present with cirrhosis about 10 yr earlier than those with HCV infection. HCV infection tends to be associated with a higher risk of decompensation, but these data should take into consideration the heterogeneity of HBV-related cirrhosis in terms of viremia levels and risk of hepatic failure. Survival shows no significant differences according to HBV or HCV etiology in Western European cirrhotic patients. 相似文献
83.
Identification of carboxypeptidase N as an enzyme responsible for C-terminal cleavage of stromal cell-derived factor-1alpha in the circulation 下载免费PDF全文
Davis DA Singer KE De La Luz Sierra M Narazaki M Yang F Fales HM Yarchoan R Tosato G 《Blood》2005,105(12):4561-4568
The chemokine stromal-derived factor-1alpha (SDF-1alpha) is an essential regulator of hematopoiesis, lymphocyte homing, pre-B-cell growth, and angiogenesis. As SDF-1alpha is constitutively expressed in many tissues, chemokine function is mostly regulated by proteolytic degradation. Human serum cleaves the 68-amino acid chemokine, SDF-1alpha, at both termini. The enzyme or enzymes responsible for the removal of the carboxy-terminal lysine from SDF-1alpha, leading to significant reduction in biologic activity, have not been identified. Using a new biochemical assay for measuring the carboxy-terminal cleavage activity, we purified from serum and plasma a peptidase that specifically removes the carboxy-terminal lysine from SDF-1alpha and identified it as carboxypeptidase N (CPN, also known as kininase I, arginine carboxypeptidase, and anaphylotoxin inactivator). We demonstrate that SDF-1alpha in serum and plasma lacks the carboxy terminal lysine, and depletion of CPN from serum and plasma significantly reduces the SDF-1alpha carboxypeptidase activity. Purified CPN effectively and specifically removes the carboxy-terminal lysine from SDF-1alpha and significantly reduces the chemokine's biologic activity as a pre-B-cell growth factor and chemoattractant. Thus, in addition to its role as a regulator of the biologic activity of kinins and anaphylatoxins, CPN is an important regulator of the biologic activity of SDF-1alpha by reducing the chemokine-specific activity. 相似文献
84.
Giovanna Leoni Philipp-Alexander Neumann Nazila Kamaly Miguel Quiros Hikaru Nishio Hefin R. Jones Ronen Sumagin Roland S. Hilgarth Ashfaqul Alam Gabrielle Fredman Ioannis Argyris Emile Rijcken Dennis Kusters Chris Reutelingsperger Mauro Perretti Charles A. Parkos Omid C. Farokhzad Andrew S. Neish Asma Nusrat 《The Journal of clinical investigation》2015,125(3):1215-1227
Epithelial restitution is an essential process that is required to repair barrier function at mucosal surfaces following injury. Prolonged breaches in epithelial barrier function result in inflammation and further damage; therefore, a better understanding of the epithelial restitution process has potential for improving the development of therapeutics. In this work, we demonstrate that endogenous annexin A1 (ANXA1) is released as a component of extracellular vesicles (EVs) derived from intestinal epithelial cells, and these ANXA1-containing EVs activate wound repair circuits. Compared with healthy controls, patients with active inflammatory bowel disease had elevated levels of secreted ANXA1-containing EVs in sera, indicating that ANXA1-containing EVs are systemically distributed in response to the inflammatory process and could potentially serve as a biomarker of intestinal mucosal inflammation. Local intestinal delivery of an exogenous ANXA1 mimetic peptide (Ac2-26) encapsulated within targeted polymeric nanoparticles (Ac2-26 Col IV NPs) accelerated healing of murine colonic wounds after biopsy-induced injury. Moreover, one-time systemic administration of Ac2-26 Col IV NPs accelerated recovery following experimentally induced colitis. Together, our results suggest that local delivery of proresolving peptides encapsulated within nanoparticles may represent a potential therapeutic strategy for clinical situations characterized by chronic mucosal injury, such as is seen in patients with IBD. 相似文献
85.
Antonella Meloni Daniele De Marchi Vincenzo Positano Maria Giovanna Neri Maurizio Mangione Petra Keilberg Maddalena Lendini Carla Cirotto Alessia Pepe 《Abdominal imaging》2015,40(8):3129-3136
Purpose
We examined different approaches aimed to deal with the signal fluctuation of pancreatic T2* values due to fat infiltration in order to obtain accurate estimates of iron overload.Methods
Pancreatic T2* values were assessed in 20 patients (13 females, 37.24 ± 9.12 years) enrolled in the Myocardial Iron Overload in Thalassemia network without and with the application of fat suppression-FS (T2*-NoFS and T2*-FS). T2* values were assessed in three different ways: (1) from the immediate fit (original T2*); (2) discarding the echoes until the achievement of a good visual concordance between the signal and the model (final_vis T2*); (3) eliminating the echoes until the achievement of a fitting error (known) <5% (final_thres T2*).Results
For the T2*-NoFS sequence the original T2* values were significantly higher than the final_vis T2* values (difference:4.8 ± 6.1 ms; P < 0.0001) and the final_thres T2* values (difference:4.3 ± 6.1 ms; P = 0.006). For the T2*-FS sequence the original T2* values were comparable to final_vis and final_thres T2* values. The original T2*-FS values were significantly different from the original T2*-NoFS values. The final_vis T2*-FS values were comparable to the final_vis T2*-NoFS values and the final_thresh T2*-FS values were comparable to the final_thresh T2*-NoFS values. For both T2*-FS and T2*-NoFS sequences, the final_thres T2* values were not significantly different from the final_vis T2* values and no bias was present.Conclusions
In the clinical practice, an accurate pancreatic iron overload assessment should be done by applying FS and, when needed, by discarding the TEs until the fitting error goes below 5%.86.
Giovanna Cilluffo Giuliana Ferrante Renato Cutrera Giorgio Piacentini Elisabetta Bignamini Massimo Landi Paola Martucci Luigi Morcaldi Fabio Midulla Giovanni Viegi Stefania La Grutta 《Journal of thoracic disease》2020,12(11):6868
BackgroundPaediatricians rarely devote any time to screening and treatment for parental tobacco use. The present project is part of a Global Alliance against Chronic Respiratory Diseases (GARD)-Italy Demonstration Project, aimed to increase the skills of primary care physicians and paediatricians as “promoter of smoking cessation”. The aims of this study were: (I) to identify latent classes of barriers and incentives for smoking cessation counseling among paediatricians using latent class analysis (LCA); (II) to investigate risk factors for inclusion into the identified classes.MethodsIn 2018, 1,500 Italian paediatricians were invited to complete an online survey on passive smoke exposure in children. LCA was used to discover underlying response patterns, and to identify respondent groups with similar attitudes toward passive smoke exposure in children. Multinomial logistic regression helped investigate which explanatory variables influenced inclusion into a class. A P value <0.05 was considered significant.ResultsThe overall response rate was 71% (n=1,071/1,500). Three classes were identified: Class 1 “passive” (n=226, 21.10%); Class 2 “unmotivated” (n=124, 11.58%); and Class 3 “proactive” (n=721, 67.32%). Assuming Class 3 as reference, ever having been a smoker was borderline associated (P=0.052) with increased probability of inclusion into Class 1 (OR =1.43, 95% CI, 1.00–2.06). Having 6–15 or ≥15 years of work experience versus having less than five years was associated with decreased probability of being in the “passive” class (OR =0.46, 95% CI, 0.22–0.96 and OR =0.49, 95% CI, 0.27–0.87, respectively), as was discussing parents’ addiction to alcohol/drugs (OR =0.50, 95% CI, 0.33–0.76).ConclusionsWe identified three profiles among Italian paediatricians related to barriers and incentives for smoking cessation promotion. Tailored educational interventions for paediatricians are required to promote smoking cessation programs. 相似文献
87.
Peter T W Kim Giovanna Saracino Linda Jennings Michael Ramsay Gregory J McKenna Giuliano Testa Tiffany L Anthony Nicholas Onaca Richard M Ruiz Robert M Goldstein Marlon F Levy Goran B Klintmalm 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(12):1083-1087
ObjectivesAdequate hepatic arterial (HA) flow to the bile duct is essential in liver transplantation. This study was conducted to determine if the ratio of directly measured HA flow to weight is related to the occurrence of biliary complications after deceased donor liver transplantation.MethodsA retrospective review of 2684 liver transplants carried out over a 25-year period was performed using data sourced from a prospectively maintained database. Rates of biliary complications (biliary leaks, anastomotic and non-anastomotic strictures) were compared between two groups of patients with HA flow by body weight of, respectively, <5 ml/min/kg (n = 884) and ≥5 ml/min/kg (n = 1800).ResultsPatients with a lower ratio of HA flow to weight had higher body weight (92 kg versus 76 kg; P < 0.001) and lower HA flow (350 ml/min versus 550 ml/min; P < 0.001). A lower ratio of HA flow to weight was associated with higher rates of biliary complications at 2 months, 6 months and 12 months (19.8%, 28.2% and 31.9% versus 14.8%, 22.4% and 25.8%, respectively; P < 0.001).ConclusionsA ratio of HA flow to weight of < 5 ml/min/kg is associated with higher rates of biliary complications. This ratio may be a useful parameter for application in the prevention and early detection of biliary complications. 相似文献
88.
89.
A comprehensive optical analysis of nanoscale structures: from thin films to asymmetric nanocavities
Giuseppe Emanuele Lio Giovanna Palermo Roberto Caputo Antonio De Luca 《RSC advances》2019,9(37):21429
A simple and robust method able to evaluate and predict, with high accuracy, the optical properties of single and multi-layer nanostructures is presented. The method was implemented using a COMSOL Multiphysics simulation platform and it has been validated by four case studies with increasing numerical complexities: (i) a single thin layer (20 nm) of Ag deposited on a glass substrate; (ii) a metamaterial composed of five bi-layers of Ag/ITO (indium tin oxide), with a thickness of 20 nm each; (iii) a system based on a three-material unit cell (AZO/ITO/Ag), but without any thickness periodicity (AZO stands for Al2O3/zinc oxide); (iv) an asymmetric nanocavity (thin-ITO/Ag/thick-ITO/Ag). A thorough study of this latter configuration reveals peculiar metamaterial effects that can widen the actual scenario in nanophotonic applications. Numerical results have been compared with experimental data provided by real ellipsometric measurements performed on the above mentioned ad hoc fabricated nanostructures. The obtained agreement is excellent, suggesting this research as a valid design approach to realize multi-band metamaterials able to work in a broad spectral range.Hyper transmission of asymmetric nanocavity metamaterials; a comprehensive optical analysis of multi-layered nanostructures. 相似文献
90.
Edoardo Troncone Alessandro Fugazza Annalisa Cappello Giovanna Del Vecchio Blanco Giovanni Monteleone Alessandro Repici Anthony Yuen Bun Teoh rea Anderloni 《World journal of gastroenterology : WJG》2020,26(16):1847-1860
Malignant gastric outlet obstruction(MGOO) is a clinical condition characterized by the mechanical obstruction of the pylorus or the duodenum due to tumor compression/infiltration, with consequent reduction or impossibility of an adequate oral intake. MGOO is mainly secondary to advanced pancreatic or gastric cancers, and significantly impacts on patients' survival and quality of life.Patients suffering from this condition often present with intractable vomiting and severe malnutrition, which further compromise therapeutic chances. Currently,palliative strategies are based primarily on surgical gastrojejunostomy and endoscopic enteral stenting with self-expanding metal stents. Several studies have shown that surgical approach has the advantage of a more durable relief of symptoms and the need of fewer re-interventions, at the cost of higher procedure-related risks and longer hospital stay. On the other hand, enteral stenting provides rapid clinical improvement, but have the limit of higher stent dysfunction rate due to tumor ingrowth and a subsequent need of frequent reinterventions. Recently, a third way has come from interventional endoscopic ultrasound, through the development of endoscopic ultrasound-guided gastroenterostomy technique with lumen-apposing metal stent. This new technique may ideally encompass the minimal invasiveness of an endoscopic procedure and the long-lasting effect of the surgical gastrojejunostomy, and brought encouraging results so far, even if prospective comparative trial are still lacking. In this Review, we described technical aspects and clinical outcomes of the above-cited therapeutic approaches, and discussed the open questions about the current management of MGOO. 相似文献