Nonparametric Information Geometry

The differential-geometric structure of the set of positive densities on a given measure space has raised the interest of many mathematicians after the discovery by C.R. Rao of the geometric meaning of the Fisher information. Most of the research is focused on parametric statistical models. In series of papers by author and coworkers a particular version of the nonparametric case has been discussed. It consists of a minimalistic structure modeled according the theory of exponential families: given a reference density other densities are represented by the centered log likelihood which is an element of an Orlicz space. This mappings give a system of charts of a Banach manifold. It has been observed that, while the construction is natural, the practical applicability is limited by the technical difficulty to deal with such a class of Banach spaces. It has been suggested recently to replace the exponential function with other functions with similar behavior but polynomial growth at infinity in order to obtain more tractable Banach spaces, e.g. Hilbert spaces. We give first a review of our theory with special emphasis on the specific issues of the infinite dimensional setting. In a second part we discuss two specific topics, differential equations and the metric connection. The position of this line of research with respect to other approaches is briefly discussed.Comment: Submitted for publication in the Proceedings od GSI2013 Aug 28-30 2013 Pari

Dolore post-operatorio nei pazienti affetti da neoplasia testa-collo: fattori predittivi ed efficacia della terapia

Negli anni è aumentata l’attenzione verso i molteplici aspetti associati alla “sfera” dolore, anche nei pazienti oncologici sottoposti a chirurgia testa-collo. Il dolore, definito infatti da diverse caratteristiche, quali l’esperienza personale, gli aspetti qualitativi della percezione, l’intensità, l’impatto emotivo, riconosce un’eziologia “multifattoriale”. Scopo del presente lavoro è stato: (i) valutare l’efficacia della terapia analgesica in pazienti affetti da tumore testa-collo e sottoposti a trattamento chirurgico; (ii) studiare le possibili variabili ed i fattori predittivi che possano influenzare l’insorgenza di dolore. Sono stati studiati 164 pazienti, affetti da neoplasia maligna del distretto testa-collo, trattati chirurgicamente tra il dicembre 2009 ed il dicembre 2013. I dati raccolti comprendono l’età, il sesso, la valutazione del rischio anestesiologico, la sede del tumore, la stadiazione TNM, il tipo di intervento effettuato, la complessità e la durata dell’intervento, le eventuali complicanze post-operatorie, i giorni di degenza post-intervento, la valutazione del dolore nei giorni 0, 1, 3 e 5 post-chirurgia. L’adeguatezza della terapia analgesica è stata espressa in termini di incidenza e prevalenza del dolore post-operatorio, le variabili legate al paziente, alla malattia, al trattamento chirurgico e farmacologico, sono state poi associate all’insorgenza del dolore così da poter descrivere eventuali fattori predittivi. Dai dati ottenuti emerge che la popolazione studiata ha ricevuto un’adeguata terapia antalgica, sia nell’immediato post-operatorio che nei giorni successivi. Non sono risultate associazioni statisticamente significative tra sesso, età ed incidenza del dolore post-chirurgico, mentre lo stadio del tumore, la complessità dell’intervento chirurgico e la sede della neoplasia hanno presentano correlazione significativa con il rischio di insorgenza di dolore post-operatorio. L’elevata prevalenza del dolore in ambito oncologico testa-collo, fa sì che un’appropriata ed attenta gestione del dolore risulti fondamentale. Nel futuro pertanto si auspica una sempre migliore comprensione dei fattori biologici, sociali e psicologici che caratterizzano la percezione del dolore ai fini di migliorarne il controllo

Prevalence of anatomical variants and coronary anomalies in 543 consecutive patients studied with 64-slice CT coronary angiography

The aim of our study was to assess the prevalence of variants and anomalies of the coronary artery tree in patients who underwent 64-slice computed tomography coronary angiography (CT-CA) for suspected or known coronary artery disease. A total of 543 patients (389 male, mean age 60.5 ± 10.9) were reviewed for coronary artery variants and anomalies including post-processing tools. The majority of segments were identified according to the American Heart Association scheme. The coronary dominance pattern results were: right, 86.6%; left, 9.2%; balanced, 4.2%. The left main coronary artery had a mean length of 112 ± 55 mm. The intermediate branch was present in the 21.9%. A variable number of diagonals (one, 25%; two, 49.7%; more than two, 24%; none, 1.3%) and marginals (one, 35.2%; two, 46.2%; more than two, 18%; none, 0.6%) was visualized. Furthermore, CT-CA may visualize smaller branches such as the conus branch artery (98%), the sinus node artery (91.6%), and the septal branches (93%). Single or associated coronary anomalies occurred in 18.4% of the patients, with the following distribution: 43 anomalies of origin and course, 68 intrinsic anomalies (59 myocardial bridging, nine aneurisms), three fistulas. In conclusion, 64-slice CT-CA provides optimal visualization of the variable and complex anatomy of coronary arteries because of the improved isotropic spatial resolution and flexible post-processing tool

Pain in head and neck cancer patients: The role of gender

Purpose: The purpose of this paper was to investigate the role of gender in the perception and tolerance of pain in head and neck cancer patients. Pain has a multifactorial etiology, characterized by personal experience and emotional impact, location, intensity and quality perception. Gender-related factors may have an impact on the development, perception and tolerance of pain. Gender medicine is an evolving transversal medical field, also focusing on algology and pain management. Methods: Literature review. A systematic electronic search was undertaken using PubMed, Embase and Cinahl databases. A selection of available studies was then performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria (http://www. prisma-statement.org/). Results: There were few studies in the literature examining the role of gender pain manifestation in head and neck cancer patients, including pain perception and tolerance after surgical treatment. However, available data show that (i) several factors can influence pain perception and tolerance among sexes, and that (ii) pain perception in head and neck cancer patients seems to be more prevalent in women, also in the postoperative stage. Conclusion: Gender Medicine is an evolving field; in the future, additional investigations could help us in better understanding the origin, the features and the differences between pain perception and tolerance between sexes, therefore leading us to provide a more specific and tailored pain therapeutic plan, also for head and neck cancer patients. © 2019 Zerbinis Publications. All rights reserved

Post-operative pain management in head and neck cancer patients: predictive factors and efficacy of therapy.

There is increasing interest about all aspects of pain sensation for patients undergoing head and neck surgery, and efforts have been made to better assess, monitor and reduce the occurrence of pain. The aetiology of pain is considered to be “multifactorial”, as it is defined by several features such as personal experience, quality perception, location, intensity and emotional impact. The aim of this paper is: (i) to evaluate the efficacy of analgesic treatment in patients with head and neck cancer treated by surgery, and (ii) to study the variables and predictive factors that can influence the occurrence of pain. A total of 164 patients, affected by head and neck cancer and surgically treated, between December 2009 and December 2013, were included in this study. Data collected include age, gender, assessment of anaesthetic risk, tumour localisation, pathological cancer stage, TNM stage, type of surgery performed, complexity and duration of surgery, post-operative complications, postoperative days of hospital stay and pain evaluation on days 0, 1, 3 and 5 post-surgery. We studied the appropriateness of analgesic therapy in terms of incidence and prevalence of post-operative pain; we also related pain to patient characteristics, disease and surgical treatment to determine possible predictive factors. The population studied received adequate pain control through analgesic therapy immediately post-surgery and in the following days. No associations between gender, age and post-operative pain were found, whereas pathological cancer stage, complexity of surgery and tumour site were significantly associated with the risk of post-operative pain. Adequate pain control is essential in oncological patients, and particularly in head and neck cancer patients as the prevalence of pain in this localisation is reported to be higher than in other anatomical sites. Improved comprehension of the biological and psychological factors that characterise pain perception will help to enhance its control in the future

Cochlear malformation and sensorineural hearing loss in the Walker-Warburg Syndrome.

We would like to present the case of a 16-month-old male baby, affected by Walker-Warburg Syndrome, characterized by lissencephaly and hydrocephalus, posterior encephalocele, cerebellar tonsils herniation into the foramen magnum

Symmetric bis-substituted and asymmetric mono-substituted nitridotechnetium complexes with heterofunctionalized phosphinothiolate ligands

The mixed bidentate ligand 2-(dicyclohexylphosphino)-ethanethiol (HL) reacts with labile nitrido-Tc precursors to afford a rare example of an asymmetric monosubstituted species [TcN(L)Cl(PPh3)], 1, along with the symmetric bis-substituted complex [TcN(L)2], 2. The latter compound, as assessed by TLC and HPLC chromatography, was found to possess the same molecular structure as the agent produced at the 'non carrier added' level utilizing the 99mTc nuclear isomer

Oxo-rhenium(V) mixed-ligand complexes with bidentate functionalized phosphines and tridentate Schiff base ligands

A series of monooxo-rhenium(V) mixed-ligand complexes containing bidentate functionalized phosphines and tridentate Schiff base (SB) ligands have been synthesized via ligand-exchange reactions starting from labile Re(V) precursors. A convenient route of synthesis is provided by the isolation of intermediate species such as [Re(O)(Ln)Cl3]- (1-3), (Ln = bidentate phosphino-phenolato or phosphino-carboxylato ligands). Subsequent addition of the relevant SB affords neutral mixed-ligand complexes of general formula [Re(O)(Ln)(SBm)] (1-3m). By reversing the addition of the two ligands, i.e. SB first followed by functionalized phosphine, the resulting mixed-ligand species do not change formulation. Conventional spectroscopic techniques and the single-crystal X-ray structure determination of the two representative compounds ([Re(O)(L1)(SBa)] (1a) and [Re(O)(L1)(SBb)] (1b)) reveal a distorted octahedral geometry around the rhenium center, with the phosphino-phenolato oxygen located trans to the oxo group and the equatorial sites filled by the SB donors and the phosphine phosphorus. It is worth noting that technetium chemistry works quite differently under the same reaction conditions. In fact, no intermediate species of the type [Tc(O)(Ln)Cl3]- can be isolated with [Tc(O)Cl(L1)2] and reduced [Tc(Ln)3] being the major compound