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Relief of jaundice in malignant biliary obstruction:When should we consider endoscopic ultrasonography-guided hepaticogastrostomy as an option?

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Hepatobiliary & Pancreatic Diseases International 2022年第3期21卷 234-240页

作者： alessandro Fugazza Matteo Colombo Marco Spadaccini Edoardo Vespa Roberto Gabbiadini Antonio Capogreco alessandro Repici Andrea Anderloni Division of Gastroenterology and Digestive Endoscopy Humanitas Research Hospital-IRCCSMilanItaly Department of Biomedical Sciences Humanitas UniversityMilanItaly

Background:Since it was first described in 2001,endoscopic ultrasonography-guided biliary drainage(EUS-BD)has emerged as an alternative procedure for achieving an endoscopic internal drainage in case of endoscopic retrograde cholangiopancreatography(ERCP)*** drainage can be achieved by either a transduodenal extrahepatic approach through EUS-guided choledochoduodenostomy(EUS-CDS),or a transgastric intrahepatic approach,namely EUS-guided hepaticogastrostomy(EUS-HGS)which already holds a remarkable place in the treatment of patients with malignant biliary *** sources:For this review we did a comprehensive search of PubMed/MEDLINE from inception to May 31,2021 for papers with a significant sample size(at least 20 patients enrolled)dealing with *** on technical success,clinical success and rate of adverse events were ***:A total of 22 studies with different design,com prising 874 patients,were *** success was achieved in about 96% of cases(ranging from 65% to 100%).Clinical success was obtained in almost 91% of cases(ranging from 76% to 100%).Overall rate of adverse events was 19%(ranging from 0% to 35%).Abdominal pain,self-limiting pneumoperitoneum,bile leak,cholangitis,bleeding,perforation and intraperitoneal migration of the stent were the most ***:Despite both safety and efficacy profile,at the moment HGS still remains a challenging procedure at every single step and must therefore be conducted by a very experienced endoscopist in interventional EUS and ERCP procedures,who is able to deal with the possible severe adverse events of this procedure.A rapid introduction in clinical practice of dedicated devices is desiderable.

关键词： EUS-guided hepaticogastrostomy EUS-guided biliary drainage Hepaticogastrostomy Interventional EUS

Identities for Catalan’s Constant Arising from Integrals Depending on a Parameter

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Acta Mathematica Sinica,English Series 2020年第10期36卷 1083-1093页

作者： Feclerica FERRETTI alessandro GAMBINI Daniele R.ITELLI Free University of Bozen Bressanone CampusViale Ratisbona 1639042 Bressanone(BZ) Sapienza Universiti di Roma Dipartirento di Matcatica"G.Castelruovo"Piazzale Aldo Moro 500185 Roma Urieersita di Bologna Dipartimento di Scienze StatisticheVia delle Bele Arti 4140126 Bologna

In this paper we provide some relationships between Catalan’s constant and the 3F2 and4F3 hypergeometric functions,deriving them from some parametric *** particular,using the complete elliptic integral of the first kind,we found an alternative proof of a result of Ramanujan for3F2,a second identity related to 4F3 and using the complete elliptic integral of the second kind we obtain an identity by Adamchik.

关键词： Catalan constant elliptic integral hypergeometric functions

Electromagnetic chirality induced by graphene inclusions in multilayered metamaterials

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Photonics Research 2014年第5期2卷 121-125页

作者： Carlo Rizza Elia Palange alessandro Ciattoni Dipartimento di Scienza e Alta Tecnologia Universitàdell’Insubriavia Valleggio 1122100 ComoItaly Consiglio Nazionale delle Ricerche CNR-SPIN67100 Coppito L’AquilaItaly Dipartimento di Scienze fisiche e chimiche Universitàdi L’Aquilavia Vetoio67100 Coppito L’AquilaItaly

We theoretically investigate the electromagnetic response of a novel class of multilayered metamaterials obtained by alternating graphene sheets and dielectric layers,the whole structure not exhibiting a plane of reflection symmetry along the stacking *** show that the electromagnetic response of the structure is characterized by a magneto-electric coupling described by an effective chiral *** the intrinsic tunability of graphene–light coupling,we prove that one can tune both the dielectric and the chiral electromagnetic response by varying the graphene chemical potential through external voltage gating.

关键词： parameter. dielectric chiral

Prognostic and predictive role of hyponatremia in cancer patients

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Journal of Cancer Metastasis and Treatment 2019年第5期4卷 41-47页

作者： alessandro Peri Sodium Unit EndocrinologyDepartment of Experimental and Clinical Biomedical Sciences"Mario Serio"University of FlorenceCareggi HospitalFlorence 50139Italy

Hyponatremia is the most frequent electrolyte disorder encountered in hospitalized patients. Several studies have demonstrated that hyponatremia is a negative prognostic factor in different clinical scenarios. Noteworthy, not only severe and acute hyponatremia has been associated with an increased risk of mortality, but also moderate of even mild chronic hyponatremia may increase the risk of death. This has been demonstrated in different categories of patients, including cancer patients. There is growing evidence that both progression free survival and overall survival are significantly reduced in cancer patients with hyponatremia compared to patients with normonatremia. One important, and still open, question is whether the worse outcome associated with hyponatremia in cancer patients is directly attributable to the electrolyte disorder itself or might be a sign of the severity of the underlying disease. With regard to this point, some basic research studies suggested that low sodium concentration stimulates per se cancer cells proliferation and invasiveness. Recent clinical evidence appears to indicate that the correction of hyponatremia is an independent and favourable prognostic factor in cancer patients. Admittedly, robust confirmatory data from clinical practice are needed, in order to validate the hypothesis that cancer patients may die for hyponatremia and not just with hyponatremia.

关键词： Hyponatremia cancer mortality prognosis vasopressin

Nonalcoholic Fatty Liver Disease (NAFLD) and Risk of Cardiac Arrhythmias: A New Aspect of the Liver-heart Axis

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Journal of Clinical and Translational Hepatology 2017年第2期5卷 134-141页

作者： alessandro Mantovani Section of Endocrinology Diabetes and Metabolism Department of Medicine University and Azienda Ospedaliera Universitaria Integrata of Verona Verona Italy

Nonalcoholic fatty liver disease (NAFLD) is a pathologic condition frequently observed in clinical *** date,the prevalence of NAFLD is approximately 25-30% among adults of the general population in Western countries but increases to approximately 70-75% among patients with type 2 diabetes *** the last decade,accumulating evidence has clearly demonstrated that patients with NAFLD have not only an increased liver-related morbidity and mortality but also an increased risk of fatal and non-fatal cardiovascular *** particular,several studies have documented the existence of an independent association among NAFLD and cardiac changes in structure and function in both non-diabetic and diabetic *** addition,mounting evidence also suggests that there is a strong relationship between NAFLD and cardiac arrhythmias,such as atrial fibrillation,QTc prolongation and ventricular *** is of clinical interest,as it could explain,at least in part,the increased risk of death for cardiovascular disease in patients with ***,seeing that cardiovascular disease complications are the leading cause of disability and death in NAFLD patients,the recent European clinical practice guidelines advised to check the cardiovascular system in all patients with *** clinical mini review will briefly describe the increasing body of evidence regarding the association between NAFLD and cardiac arrhythmias,and discuss the potential biological mechanisms underlying this association.

关键词： Nonalcoholic fatty liver disease Cardiovascular disease Cardiac arrhythmias Cardiac complications

Application of homotopy perturbation method to the radial thrust problem

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Astrodynamics 2023年第2期7卷 251-258页

作者： Lorenzo Niccolai alessandro A.Quarta Giovanni Mengali Department of Civil and Industrial Engineering University of PisaI-56122Italy

The dynamics of a spacecraft propelled by a continuous radial thrust resembles that of a nonlinear *** is analyzed in this work with a novel method that combines the definition of a suitable homotopy with a classical perturbation approach,in which the low thrust is assumed to be a perturbation of the nominal Keplerian *** homotopy perturbation method provides the analytical(approximate)solution of the dynamical equations in polar form to estimate the corresponding spacecraft propelled trajectory with a short computational *** accuracy of the analytical results was tested in an orbital-targeting mission scenario.

关键词： radial thrust homotopy perturbation method nonlinear oscillator trajectory approximation

Analytical solution to logarithmic spiral trajectories with circumferential thrust and mission applications

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Astrodynamics 2022年第4期6卷 413-427页

作者： Marco Bassetto alessandro A.Quarta Giovanni Mengali Department of Civil and Industrial Engineering University of PisaPisaⅠ-56122Italy

This study made use of a shape-based method to analyze the orbital dynamics of a spacecraft subject to a continuous propulsive acceleration acting along the circumferential *** the assumption of a logarithmic spiral trajectory,an exact solution to the equations of motion exists,which allows the spacecraft state variables and flight time to be expressed as a function of the angular *** is also a case characterized by specific initial conditions in which the time evolution of the state variables may be analytically *** this context,the presented solution is used to analyze circle-to-circle trajectories,where the combination of two impulsive maneuvers and a logarithmic spiral path are used to accomplish the *** determined results are then applied to the achievement of the Earth–Mars and the Earth–Venus transfers using actual data from a recent thruster developed by NASA.

关键词： circumferential thrust logarithmic spiral trajectory circle-to-circle transfer

Multifactorial nature of hepatocellular carcinoma drug resistance: Could plant polyphenols be helpful?

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World Journal of Gastroenterology 2007年第14期13卷 2037-2043页

作者： Natale D'alessandro Paola Poma Giuseppe Montalto Department of Pharmacological Sciences University of Palermo Italy Department of Clinical Medicine University of Palermo PalermoItaly

Primary hepatocellular carcinoma （HCC） is a quite frequent tumor which results in high mortality and most often exhibits a poor response to present drug therapies. Clearly, a thorough understanding of the biological bases of this malignancy might suggest new strategies for its treatment. Here we examine the evidences that both ＂pharmacological＂ mechanisms （e.g. drug transporter or detoxification enzyme over-expression） and alterations in other critical factors, including the IAPs （Inhibitory of Apoptosis Proteins）, involved in enhancement of cell survival and proliferation may determine the therapeutic resistance of HCC; we also underline the possible role in the process of the activation of transcription factors, like NF-κB, capable of contemporaneously up-regulating the mechanisms discussed. On this basis, we finally comment on the possible use of natural multi-targeted antitumoral agents like plant polyphenols to achieve sensitization to treatments in HCC.

关键词： Hepatocellular carcinoma Drug resistance Drug transporters Inhibition of cell death LAPs NF-κB Plant polyphenols

Importance of initial buoyancy field on evolution of mantle thermal structure:Implications of surface boundary conditions

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Geoscience Frontiers 2015年第1期6卷 3-22页

作者： Petar Gliovi alessandro M.Forte GEOTOP Universite du Quebec a MontrealCP 8888Succursale Centre-Ville

Although there has been significant progress in the seismic imaging of mantle heterogeneity, the outstanding issue that remains to be resolved is the unknown distribution of mantle temperature anomalies in the distant geological past that give rise to the present-day anomalies inferred by global tomography models. To address this question, we present 3-D convection models in compressible and self-gravitating mantle initialised by different hypothetical temperature patterns. A notable feature of our forward convection modelling is the use of self-consistent coupling of the motion of surface tectonic plates to the underlying mantle flow, without imposing prescribed surface velocities （i.e., p/ate-like boundary condition）. As an approximation for the surface mechanical conditions before plate tectonics began to operate we employ the no-slip （rigid） boundary condition. A rigid boundary condition dem- onstrates that the initial thermally-dominated structure is preserved, and its geographical location is fixed during the evolution of mantle flow. Considering the impact of different assumed surface boundary conditions （rigid and plate-like） on the evolution of thermal heterogeneity in the mantle we suggest that the intrinsic buoyancy of seven superplumes is most-likely resolved in the tomographic images of present-day mantle thermal structure. Our convection simulations with a plate-like boundary condition reveal that the evolution of an initial cold anomaly beneath the Java-lndonesian trench system yields a long-term, stable pattern of thermal heterogeneity in the lowermost mantle that resembles the present- day Large Low Shear Velocity Provinces （LLSVPs）, especially below the Pacific. The evolution of sub- duction zones may be, however, influenced by the mantle-wide flow driven by deeply-rooted and long- lived superplumes since Archean times. These convection models also detect the intrinsic buoyancy of the Perm Anomaly that has been identified as a unique slow feature d

关键词： Dynamics: convection currents, and mantleplumes Hotspots Seismic tomography Planetary tectonics CMB topography Perm Anomaly