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61.
Lugaresi A Di Iorio A Iarlori C Reale M De Luca G Sparvieri E Michetti A Conti P Gambi D Abate G Paganelli R 《Experimental gerontology》2004,39(4):653-657
Cytokines appear to be involved in the pathogenesis of Alzheimer's Disease (AD). Their modulation by treatment has been investigated only in a few studies. The aim of our study was to evaluate the effect of acetylcholinesterase inhibitors (AChEI) on Interleukin-4 (IL-4) production in AD patients. IL-4 levels were measured by ELISA on peripheral blood mononuclear cell cultures in the presence or absence of Concanavalin A or Phytohaemagglutinin. Linear regression analysis shows that patients who have been treated, have higher levels of IL-4 independently from age, gender and comorbidity. The increased production of IL-4 in AChEI treated patients might represent an additional mechanism through which AChEI act on AD progression. 相似文献
62.
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
63.
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
64.
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%.65.
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
66.
67.
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
68.
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
69.
Giuseppe Limongelli Teo Roselli Giuseppe Pacileo Paolo Calabró Valeria Maddaloni Daniele Masarone Lucia Riegler Rita Gravino Raffaella Scarafile Gemma Salerno Tiziana Miele Antonello D’Andrea Lucio Santangelo Massimo Romano Giovanni Di Salvo Maria Giovanna Russo Raffaele Calabró 《Internal and emergency medicine》2014,9(1):43-50
Cardiotrophin-1 (CT-1) is a member of the interleukin (IL-6) family of cytokines. Plasma CT-1 levels correlate with the left ventricle mass index in patients with dilatated cardiomyopathy and congestive heart failure (CHF). The aim of this paper was to evaluate CT-1 plasma levels, before and after cardiac resynchronization therapy CRT, and to characterizeits prognostic role in patients with CHF. Fifty-two consecutive patients (M/F = 39/13; 56 ± 11 years old) underwent clinical and echocardiographic evaluation, and blood sample collection at baseline. The same evaluation was repeated 6.4 ± 0.79 months after CRT. Patients with a decreased LV end-systolic volume by at least 15% (reverse remodeling) were considered echo responders to CRT. Twenty-nine patients (56%) were responders to CRT. After CRT, only 15 patients (29%) showed increased CT-1 after CRT. They were all non responders to CRT. A multivariate, logistic modelshowed CT-1 as an independent predictor of CRT echo response (p = 0.005; OR 0.97). During follow-up (18 ± 7 months), 21 cardiac events in 18 patients occurred. A Cox multivariable model showed plasma BNP pre-CRT (p = 0.02; CI 1.2–5.6; OR 3.1) and CT1 post-CRT (p = 0.01; CI 1.4–4.3; OR 2.7) as independent predictors of cardiac events. Analysis of CT-1 plasma levels deserves future consideration for larger, longitudinal studies in patients with CHF. 相似文献
70.
G Liguori L Assisi C Squillacioti S Paino N Mirabella A Vittoria 《General and comparative endocrinology》2012,179(1):137-142
The orexins A (oxA) and B are peptides discovered in the rat hypothalamus and successively found in some peripheral organs of the mammalian body. They binds two protein G-coupled receptors defined receptor 1 (ox1r) and 2 for orexins, the first of which is highly specific for oxA while the second binds both the peptides with equal affinity. This work aimed to detect the presence of oxA and ox1r in the testis of the South American camelid alpaca (Vicugna pacos) and investigate the role played by them on Leydig cell steroidogenesis. The species alpaca acquired, in the last years, increasing zootechnical interest for the quality of the wool produced and its breeding spread from the country of origin to USA, Australia and Europe. Immunohistochemistry allowed us to detect oxA in Leydig and Sertoli cells, spermatogonia, resting spermatocytes, round and oval spermatids. Ox1r-immunoreactivity was found in Leydig cells and round, oval and elongated spermatids. The expression of the two peptides in tissue extracts was established by using Western blotting technique. Such results demonstrated that in the alpaca testis exists in a cellular complex able to produce and/or internalize oxA. Finally, the effect of oxA on steroidogenesis was investigated by means of in vitro cultured thin testis slices which were added with oxA or/and Müllerian Inhibiting Substance (MIS), a steroidolitic agent basally produced by the Sertoli cell. OxA evoked increase of testosterone production while MIS a decrease. The consecutive addition of oxA and MIS, or vice versa, highlighted an antagonistic interplay between the two substances which has been thought to be the main molecular event at the basis of the oxA-stimulated steroidogenesis mechanism. 相似文献