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111.
HIV-1 infection predisposes to the development of specific types of cancer. Most cancers seen in the AIDS setting are related to oncogenic virus infections, such as Epstein-Barr virus (EBV), Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) and human papillomavirus (HPV). It is generally assumed that HIV-1 infection play a passive role in cancer development by impairing the host immune surveillance and increasing the risk of oncogenic virus infection. Recent insights, however, indicate that HIV-1 infection more actively promotes cancer growth. Experimental evidence has shown that HIV-1-encoded proteins can directly induce tumor angiogenesis and enhance KSHV transmission to target cells. Clinical evidence suggests that the oncogenicity of HPV is altered by the presence of HIV-1 infection irrespective of host immune status. The introduction of highly active antiretroviral therapy (HAART) has dramatically decreased the incidence of KS whereas the impact of HAART is variable in EBV-related lymphoma and HPV-related cervical cancer, suggesting that additional factors are involved in the pathogenesis of these cancers. Understanding the direct and indirect roles of HIV-1 in the pathogenesis of neoplastic conditions could provide the rationale for prevention and development of new treatments for AIDS-associated malignancies. 相似文献
112.
113.
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
114.
Identification of carboxypeptidase N as an enzyme responsible for C-terminal cleavage of stromal cell-derived factor-1alpha in the circulation
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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
115.
Tissue Doppler Imaging predicts central sleep apnea in patients with chronic heart failure: data from the Daunia Registry
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116.
Danilo Alessio Di Stefano Paolo Arosio Adriano Piattelli Vittoria Perrotti Giovanna Iezzi 《The journal of advanced prosthodontics》2015,7(1):51-55
PURPOSE
Bone density at implant placement site is a key factor to obtain the primary stability of the fixture, which, in turn, is a prognostic factor for osseointegration and long-term success of an implant supported rehabilitation. Recently, an implant motor with a bone density measurement probe has been introduced. The aim of the present study was to test the objectiveness of the bone densities registered by the implant motor regardless of the operator performing them.MATERIALS AND METHODS
A total of 3704 bone density measurements, performed by means of the implant motor, were registered by 39 operators at different implant sites during routine activity. Bone density measurements were grouped according to their distribution across the jaws. Specifically, four different areas were distinguished: a pre-antral (between teeth from first right maxillary premolar to first left maxillary premolar) and a sub-antral (more distally) zone in the maxilla, and an interforaminal (between and including teeth from first left mandibular premolar to first right mandibular premolar) and a retroforaminal (more distally) zone in the lower one. A statistical comparison was performed to check the inter-operators variability of the collected data.RESULTS
The device produced consistent and operator-independent bone density values at each tooth position, showing a reliable bone-density measurement.CONCLUSION
The implant motor demonstrated to be a helpful tool to properly plan implant placement and loading irrespective of the operator using it. 相似文献117.
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
118.
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%.119.
Silvia Marino Andrea Di Cataldo Gaetano Magro Salvatore D'Amico Milena La Spina Vincenzo Di Benedetto Mariaclaudia Meli Carla Moscheo Giovanna Russo 《Clinical Case Reports》2015,3(3):179-182
We report a rare clinical presentation of childhood Hodgkin lymphoma with immune thrombocytopenia. Diagnostic biopsy of the abdominal mass was performed after administration of intravenous immunoglobulins, steroids, and platelet transfusion. Concomitant thrombocytopenia complicated the whole diagnosis work up and the initial management of neoplasia. 相似文献
120.
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