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Dissipative dynamics at first-order quantum transitions
Get PDFWe investigate the effects of dissipation on the quantum dynamics of many-body systems at quantum transitions, especially considering those of the first order. This issue is studied within the paradigmatic one-dimensional quantum Ising model. We analyze the out-of-equilibrium dynamics arising from quenches of the Hamiltonian parameters and dissipative mechanisms modeled by a Lindblad master equation, with either local or global spin operators acting as dissipative operators. Analogously to what happens at continuous quantum transitions, we observe a regime where the system develops a nontrivial dynamic scaling behavior, which is realized when the dissipation parameter u (globally controlling the decay rate of the dissipation within the Lindblad framework) scales as the energy difference Δ of the lowest levels of the Hamiltonian, i.e., u∼Δ. However, unlike continuous quantum transitions where Δ is power-law suppressed, at first-order quantum transitions Δ is exponentially suppressed with increasing the system size (provided the boundary conditions do not favor any particular phase)
Territorialità attiva, partecipazione, alternative allo sviluppo
No full textParadigma della territorialità e metodo della ricerca-azione; ruolo sociale e civile della ricerca attiv
Outcome and Safety of Sorafenib in Metastatic Renal Cell Carcinoma Dialysis Patients: A Systematic Review
No full textFew data are available about sorafenib use in patients with metastatic renal cell carcinoma (mRCC) undergoing hemodialysis. No systematic review has been previously performed about this issue. The objective of the present review is to investigate pharmacokinetics and clinical outcomes of sorafenib in mRCC patients undergoing hemodialysis. According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, all the literature about mRCC dialysis patients receiving sorafenib, published from January 1946 to August 2015, was evaluated. Applying inclusion/exclusion criteria, 11 articles were selected for the analysis; 1 patient from our department was also included. The investigated outcomes were pharmacokinetics, toxicity, response rate, progression-free survival, and overall survival where available. A total of 36 patients were included. Median treatment duration was 6.0 months on overall population; median progression-free survival was 6.3 months (calculated on 19 patients); response rate was 22% (on 29 patients); median overall survival was 14.9 months (on 28 patients). Of note, 24 patients started sorafenib at reduced dose; 6 of 36 patients (17%) required dose reduction due to adverse events (AEs). Sorafenib treatment was discontinued in 7 patients (19%) because of AEs. Most of AEs were Grade 1-2; severe toxicities (Grade 4-5) included G4 anemia (1 case), G4 hypertension (1 case), G4 cerebellar hemorrhage (1 patient), and a case of G5 subarachnoid hemorrhage. This review confirmed the efficacy of sorafenib treatment in mRCC patients receiving hemodialysis. Nevertheless, drug toxicity seems to be increased in these patients, despite the initiation of therapy at reduced doses; therefore, sorafenib should be used with caution in dialysis patients
Parkinson's disease and multiple system atrophy: Reliability and limits of an early neuro-urologic evaluation
No full textPrimary Retroperitoneal Cystoadenocarcinoma: A Systematic Review
No full textBackground/Aims: The aim of this study was to perform a systematic review on primary retroperitoneal cystoadenocarcinoma (PRC), which is an extremely rare disease. Methods: According to PRISMA guidelines, all the literature about PRC from 1977 to 2015 was reviewed. Thirty articles were selected; characteristics of the patients were collected and described; time to recurrence and overall survival (OS) were investigated when available. Results: Thirty seven patients were included of whom 33 were females; the median age at presentation was 43. PRC was more common in postmenopausal women. Surgery was the standard therapy; the role of chemotherapy and/or radiotherapy was uncertain. Thirty percent of the patients relapsed after 58 months from the surgery; the rupture of the cyst occurred in 13% of the cases and it was associated with poor prognosis as well as premenopausal status. At 125 months from the diagnosis, 72% of the patients were alive and the median OS was not reached. Conclusions: The present systematic review about PRC is the first performed until the date of drafting this paper. We described some clinical features of PRC and their possible prognostic value. No conclusive data can be presented due to the small population analyzed and to publication bias
FRACTURE HEALING METABOLISM AND CELLULAR ACTIVITY IN OSTEOPOROTIC PATIENTS WITH FRAGILITY FRACTURES COMPARED WITH YOUNGER PATIENTS' FRACTURES
No full textPancreatic neuroendocrine tumors: A focus on the current classification and molecular targeted therapy
No full textAlthough their incidence has been rising over the last decades, pancreatic neuroendocrine tumors (PNETs) are relatively uncommon,
accounting for less than 5% of all primary pancreatic malignancies. They are classified based on morphological and biological characteristics.
The World Health Organization (WHO) classification from 2000 subcategorizes gastroenteropancreatic neuroendocrine tumors into welldifferentiated
tumors, well-differentiated carcinomas, and poorly differentiated carcinomas; the TNM staging system from 2006 considers
three ‘‘G’’ groups based on the Ki-67 level and three ‘‘T’’ groups related to the size. Retrospective analyses confirmed the prognostic
relevance of both WHO and TNM staging systems for PNETs. As for treatment, chemotherapy, somatostatin analogs, interferon, and peptide
radioreceptor therapy can have a role in PNETs. Over the last decade several molecular targeted agents have been studied. Among them
sunitinib and everolimus are in the most advanced phase of clinical investigation. This is a literature review, based on a Medline search for
pancreatic neuroendocrine tumor and carcinoma, which will focus on the clinical importance of classifications and the advances of molecular
targeted therapies in PNET
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