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Virulence gene expression of three hypervirulent S. pyogenes M1T1 and membrane vesicles isolation
No full textThe genus Steptococcus [Rosenbach, 1844] consists of catalase-negative, Gram-positive cocci which are arranged in pairs and chains and are usually facultatively anaerobic. Streptococci are a diverse collection of species inhabiting many body sites and they are both commensals and pathogens. In particular, nonpathogenic streptococci, are the most abundant bacterial species at the oropharyngeal level, and they have been found to exert an important role in the protection against pathogenic agents causing inflammation and infections [Tagg JR et al., 2003]. Much attention has recently been devoted to the analysis of the oral microbiota to develop bacteriotherapy focused on prevention and/or treatment of upper respiratory tract infections. In this regard, a key species is Streptococcus salivarius, a lactic acid bacterium that is mainly encountered in the mouths of human beings. It is the first commensal bacterium that appears in the oral cavity of newborns where it colonizes the upper respiratory tract [Aas JA et al., 2005] and persists there as a predominant member of the native microbiota throughout the life of its human and sole natural host [Favier CF et al., 2002]. Many LAB (Lactic Acid Bacteria) strains, including S.salivarius, are prolific producers of bacteriocins, which are an abundant and diverse group of ribosomally synthesized antimicrobial peptides produced by bacteria that kill or inhibit species closely related to the producer bacterium. Furthermore, according to several studies, large populations of S.salivarius efficiently adhere to oral epithelial cells, especially the papillary surface of the tongue that is a strategic location to carry out a population surveillance within the oral microbiota [Tagg JR et al., 1983; Wescombe PA et al., 2010 ]. The presence of an adhesion system such as pili, fibrils, saliva-binding proteins and host-cell-binding proteins, together with its high competition rate, helps this species to stay in the human mouth [Nobbs AH et al., 2009].
In our laboratory, during my PhD studies, we characterized one strain, S.salivarius 24SMBc, isolated from one healthy child that showed excellent inhibitory activity against S.pneumoniae and S.pyogenes and a potent capacity of adhesion to HEp-2 cells. The main aim of this study was to evaluate the clinical evidence of a probiotic application of S.salivarius 24SMBc for the prevention or reduction of recurrent medium otite (OM) children [Santagati M et al., 2014]. Therefore, this strain was included in a randomized, placebo-controlled, double-blind paediatric trial that involved 100 otitis prone children. This preliminary study showed a reduction of OM episodes in children who received the intranasal administration of this probiotic with respect to children treated with placebo [Santagati M et al., 2014].
The study of S.salivarius 24SMBc ended with the production and marketing of a new medical device, the Rinogermina nasal spray, in collaboration with D.M.G s.r.l Italy.
Streptococci, as mentioned above, include both nonpathogenic and pathogenic bacteria. In particular, Streptococcus pyogenes (group A streptococci, GAS) is an exclusive human bacterial pathogen. The virulence potential of this species is tremendous. Interactions with humans range from asymptomatic carriage over mild and superficial infections of skin and mucosal membranes up to systemic purulent toxic-invasive disease manifestations [Fiedler T et al., 2015]. Simultaneously with the study of S.salivarius 24SMBc, my PhD project focalized on global regulation of virulence expression genes of three hypervirulent strains of Streptococcus pyogenes [Santagati M et al., 2014] and their eventual production of membrane vesicles like new delivery system of virulence-associated components
Image Representation using Consensus Vocabulary and Food Images Classification
No full textDigital images are the result of many physical factors, such as illumination, point of view an thermal noise of the sensor. These elements may be irrelevant for a specific Computer Vision task; for instance, in the object detection task, the viewpoint and the color of the object should not be relevant in order to answer the question "Is the object present in the image?". Nevertheless, an image depends crucially on all such parameters and it is simply not possible to ignore them in analysis. Hence, finding a representation that, given a specific task, is able to keep the significant features of the image and discard the less useful ones is the first step to build a robust system in Computer Vision.
One of the most popular model to represent images is the Bag-of-Visual-Words (BoW) model. Derived from text analysis, this model is based on the generation of a codebook (also called vocabulary) which is subsequently used to provide the actual image representation. Considering a set of images, the typical pipeline, consists in:
1. Select a subset of images to be the training set for the model;
2. Extract the desired features from the all the images;
3. Run a clustering algorithm on the features extracted from the training set: each cluster is a codeword, the set containing all the clusters is the codebook;
4. For each feature point, nd the closest codeword according to a distance function or metric;
5. Build a normalized histogram of the occurrences of each word.
The choices made in the design phase influence strongly the final outcome of the representation. In this work we will discuss how to aggregate di fferent kind of features to obtain more powerful representations, presenting some state-of-the-art methods in Computer Vision community. We will focus on Clustering Ensemble techniques, presenting the theoretical framework and a new approach (Section 2.5).
Understanding food in everyday life (e.g., the recognition of dishes and the related ingredients, the estimation of quantity, etc.) is a problem which has been considered in different research areas due its important impact under the medical, social and anthropological aspects. For instance, an insane diet can cause problems in the general health of the people. Since health is strictly linked to the diet, advanced Computer Vision tools to recognize food images (e.g., acquired with mobile/wearable cameras), as well as their properties (e.g., calories, volume), can help the diet monitoring by providing useful information to the experts (e.g., nutritionists) to assess the food intake of patients (e.g., to combat obesity). On the other hand, the great diffusion of low cost image acquisition devices embedded in smartphones allows people to take pictures of food and share them on Internet (e.g., on social media); the automatic analysis of the posted images could provide information on the relationship between people and their meals and can be exploited by food retailer to better understand the preferences of a person for further recommendations of food and related products. Image representation plays a key role while trying to infer information about food items depicted in the image. We propose a deep review of the state-of-the-art two different novel representation techniques
Self-assembled Plasmonic Nanostructures for Thin Film Photovoltaics
No full textThe aim of this thesis is to explore the optical properties of localized surface plasmon resonance sustained by self-assembled metallic nanoparticles (NPs) for the light
trapping application in thin lm photovoltaics (PV).
Photovoltaics is able provide safe and clean electricity of the future, inparticular, thin lms solar cells have a potential to increase the competitiveness of PV through a
substantial reduction of the manufacturing cost. However, an essential step it to develop an e cient, reliable and inexpensive light trapping scheme in order to maximize
absorption of the near-infrared radiation in the cell and balance the reduced volume of semiconductor material. Recently there is a growing interest in the application of
subwavelength metallic NPs for light trapping as they can scatter light e ciently over a broad wavelength range of the solar spectrum, due to the to the phenomena known as
localized surface plasmon (LSP) resonance.
A systematic study of the correlation between the structural and the optical properties of self-assembled silver nanostructures fabricated on soda-lime glass by a solid-state dewetting (SSD) process, which consist in thermallyinduced morphology transformation from a thin lm to an array of islands or nanoparticles is reported. It is shown that four distinct types of morphology tend to form in speci c ranges of fabrication parameters, which is quantitatively summarized by a proposed structural-phase diagram and allows to identify the fabrication conditions in which preferable, uniformly spaced and circular NPs are obtainable. The optical properties of the NPs stay in qualitative agreement with the trends predicted by Mie theory, and correlate with the surface coverage (SC) distributions and the mean SC size.
As a step forward towards the implementation in thin lm photovoltaics, the NPs are incorporated on the rear side of thin silicon fillm in two distinct arrangements, namely superstrate and substrate. In superstrate configration,The coupling e ciency increases with NPs' average size, decreases with increasing distance between silicon, and is signi cantly smaller for spherical than for hemispherical NPs, which stay in qualitative agreement with theoretical predictions. A novel procedure, involving a combination of phothermal de
ection spectroscopy and fourier transform photocurrent spectroscopy, employed for substrate con guration lms allowed for the quanti cation of useful and parasitic absorption. It is demonstrated that the optical losses in the NPs are insigni cant in the 500-730nm wavelength range, beyond which they increase rapidly with increasing illumination wavelength. Furthermore, a broadband enhancement of 89.9% of useful absorption has been achieved.
Susequantly, a successful implementation of a plasmonic light trapping scheme implemented in a thin lm a-Si:H solar cell in plasmonic back re
ector (PBR) con guration. The
optical properties of the PBRs are systematically investigated according to the morphology of the self-assembled silver nanoparticles (NPs), which can be tuned by the
fabrication parameters. By analyzing sets of solar cells built on distinct PBRs, it is shown that the photocurrent enhancement achieved in the a-Si:H light trapping window
(600-800 nm) stays in linear relation with the PBRs di use re
ection. The best-performing PBRs allow a pronounced broadband photocurrent enhancement in the cells which is
attributed not only to the plasmon-assisted light scattering from the NPs but also to the front surface texture originated from the conformal growth of the cell material over the particles. As a result, remarkably high values of Jsc and Voc are achieved in comparison to those previously reported in the literature for the same type of devices.
Furthermore an attempt on implementation of the plasmonic light trapping in the industrial a-Si/ c-Si double junction solar cells is reported
Recupero delle ferrovie dismesse: analisi e progetto in contesti paesaggistici siciliani
No full textNegli ultimi decenni molte linee ferroviarie sono entrate in disuso a causa della crescente affermazione del trasporto automobilistico e aereo e a causa dell inadeguatezza alle attuali esigenze di trasporto delle linee e delle infrastrutture connesse. Oggi le linee ferroviarie dismesse costituiscono spesso la base di un ricco patrimonio naturale che in molti Paesi del mondo si sceglie di recuperare e trasformare in percorsi verdi: tale trasformazione massimizza i benefici per la comunità locale a fronte di un minimo investimento di risorse finanziarie. In Italia sono circa 8.000 i chilometri ferroviari dismessi e, dopo molti anni di studi, ricerche e convegni sulla tematica, si è potuto assistere alle prime realizzazioni concrete che fanno aumentare di giorno in giorno i chilometri di percorsi dedicati alla mobilità non motorizzata. Nonostante tali confortanti presupposti continua ad essere necessario implementare le ricerche in tal senso: mancano progetti e indicazioni operative specifiche per la creazione di un sistema integrato di greenways in grado di svolgere funzioni di valorizzazione e fruizione delle risorse storico-culturali e delle attività turistico-ricettive. Si può dunque pensare di ripristinare tali percorsi dismessi trasformandoli in greenways dove l esperienza del viaggio costituisce un insieme di turismo, cultura e sport.
L obiettivo è quello di fornire spunti di riflessione in merito alla possibilità di recupero e trasformazione di percorsi ferroviari dismessi in greenways, dimostrando come sia possibile riutilizzare tali tracciati, salvaguardando la qualità del paesaggio e fornendo nuove opportunità di utilizzo del patrimonio storico-culturale. La ricerca è suddivisa in due parti: la prima è dedicata allo stato dell arte del fenomeno delle ferrovie abbandonate e relativa trasformazione in greenways; la seconda invece, una volta individuata l area di studio, è rivolta all applicazione di un metodo basato sull analisi multicriteri in ambiente GIS, attraverso il quale è possibile valutare inizialmente l idoneità del territorio ad accogliere un processo di recupero dei tracciati ferroviari dismessi in relazione alle risorse territoriali presenti, e successivamente valutare l idoneità alla riconversione dei tracciati ferroviari presenti nel territorio analizzato in base a proprie caratteristiche e condizioni al contorno.
I primi risultati hanno indicato l opportunità di scegliere quale area di studio gli ambiti paesaggistici afferenti al siracusano, indicati dalle linee guida del Piano Territoriale Paesaggistico della Sicilia. Infatti è emerso che nella regione tali ambiti sono fra quelli maggiormente ricchi di risorse naturali, culturali, e artistiche. Successivamente l applicazione multicriteriale associata al GIS ha permesso di individuare lo scenario che può avvalersi maggiormente della riconversione delle ferrovie dismesse in greenways fra i tre scenari ipotizzati, A1-finalità rurale, A2- finalità turistico/culturale, A3- finalità ambientali. Lo scenario A2 ha assunto un peso maggiore; per tale scenario è stata verificata la idoneità al recupero di due linee dismesse della provincia (Siracusa/Vizzini, Noto/Pachino) e, conseguentemente, sono stati scelti i tratti ferroviari sui quali approntare progetti di recupero e riconversione. I risultati progettuali ottenuti possono essere di interesse per i diversi attori, pubblici o privati che vogliono in futuro intervenire per il recupero e la valorizzazione, non solo dei singoli tracciati, ma anche del territorio e del paesaggio. Gli elaborati progettuali possono essere assunti come riferimento dai quali partire per sviluppare progetti di dettaglio a livello di tratti ed elementi. Inoltre essi costituiscono un risultato applicativo delle fasi di analisi e valutazione, dimostrando la validità dell approccio teorico. Lo studio, pur riferendosi ad un ambito territoriale preciso, fornisce riferimenti metodologici di validità generale applicabili in altri contesti
Formulazione di un metodo di progetto per l'adeguamento sismico di telai in C.A. mediante controventi ad instabilità impedita
No full textMolti degli edifici in c.a. esistenti sono stati progettati in passato per soli carichi verticali o per modeste azioni sismiche e necessitano di un intervento di adeguamento sismico per rispondere ai requisiti prestazionali previsti dalle normative attuali. Nella presente Tesi di Dottorato è proposto e validato un metodo basato sugli spostamenti per l adeguamento sismico di tali strutture mediante l impiego di controventi a instabilità impedita (BRBs, Buckling-Restrained Braces), la cui idea di base è stata recentemente presentata per il progetto di telai in acciaio con BRBs (Bosco e Marino, 2013; Bosco et al., 2014). I BRBs sono controventi dissipativi in acciaio che manifestano un ciclo isteretico stabile e un comportamento simile in trazione e in compressione, con una buona capacità di dissipazione energetica grazie agli alti valori di duttilità che possono raggiungere. La procedura di progetto proposta permette di definire, a ogni piano, la rigidezza e la resistenza dei BRBs, tramite la scelta di valori appropriati di area della sezione trasversale, lunghezza del segmento duttile e tensione di snervamento dell acciaio. Il metodo di progetto prevede l imposizione di due requisiti: il requisito sugli spostamenti di interpiano riduce la domanda sismica a valori compatibili con la capacità deformativa della struttura e permette di determinare a ciascun piano la rigidezza laterale aggiuntiva da fornire tramite i controventi; il controllo della duttilità massima subita dai BRBs durante il sisma consente di stabilire la tensione di snervamento e, quindi, la resistenza assiale necessaria per i controventi. Il metodo proposto è applicato a tre casi studio rappresentativi di edifici esistenti che necessitano di adeguamento sismico. L efficacia del metodo è evidenziata tramite analisi dinamiche non lineari condotte sulle strutture controventate al variare dei parametri di progetto
Metal organic chemical vapor deposition of functional fluoride phases
No full textInorganic metal fluorides and oxide-fluorides have significant importance in the development of many new technologies, and are impacting various key points of modern life, that is, energy production and storage, microelectronics and photonics, catalysis, automotive, building, etc.
In the past few years, fluoride materials have attracted a great and increasing interest due to their multifunctional properties, such as ferroelectricity, induced ferro/antiferromagnetism, thermal stability, high transparency and low phonon energy.
Currently, the research on multiferroic materials is directed towards Bi-containing perovskite such as BiFeO3 or BiMnO3 and toward both hexagonal and orthorhombic rare-earth manganites such as HoMnO3 and TbMnO3.
Among the few known ferroelectric fluoride crystals, the barium fluoride BaMF4 (M=Mg, Mn, Co, Ni, Zn) phases have recently caught substantial attention in view of their interesting and multifunctional properties.
The BaMF4 multiferroics have been proposed as systems where is possible to incorporate both magnetism and ferroelectricity in the same phase.
The goal of this work is to explore a new class of multiferroic non-oxide based materials, focusing on the class of BaMF4 systems, to widen the range of candidates for magnetoelectric device applications. In addition, fluoride compounds have compelling advantages for many optical applications due to their unique combination of low phonon energy, high UV absorption edge energy, and relatively weak crystal field.
Compared with oxides, fluorides are considered to be efficient hosts for down-conversion (DC) and upconversion (UC) luminescence of rare earth (RE) ions due to their low phonon energies and optical transparency over a wide wavelength range.
The choice of host materials is of great importance in designing lanthanide-based luminescent UC materials for efficient practical applications.
Among the fluorides reported, rare earth (RE) doped NaYF4 and NaGdF4 are considered as the most efficient DC and UC host lattices, and have recently raised increasing attention. Many applications of RE-doped fluorides have been demonstrated, such as lasers, optical communications, display devices, and so on.
On the other hand, trivalent RE-doped MF2 (with M=Sr, Ca, Ba, Cd) compounds are also considered a suitable material characterized by low energy phonons (usually less than 300 cm-1) and large transfer coefficients between the RE ions. In this typology of halide hosts, multiphonon relaxation is thought to be strongly suppressed and therefore efficient UC luminescence can be obtained.
In this context, the present work discusses about some different rare-earth doped fluoride materials based on NaREF4 and MF2 host lattices, which possess physical properties of technological interest. In this study, Metal Organic Chemical Vapor Deposition (MOCVD) approaches have been used to fabricate the fluoride phases of interest in form of thin films. A systematic study of precursors suitable for the MOCVD growth of the fluoride films has been addressed. The synthesized films have been characterized from a structural, morphological and compositional point of view
Attività amensalistica di Lactobacillus spp. isolati da campioni umani
No full textLactobacillus is a bacterial genus belonging to LAB (Lactic Acid Bacteria) and they are among the most common probiotics. Recent guidelines on probiotics, issued by the Italian Ministry of Health, state that, on the basis of the available literature, the amount sufficient to obtain a temporary colonization of the intestine by a probiotic strain is at least 10^9 living cells.
A microorganism can be defined as a probiotic strain if it is of human origin, if it survive to the gastrointestinal tract, resisting the acidity of the stomach and the action of bile, and it should have immunostimulant activity.
In addition, the strain should be able to adhere to the mucosa causing no toxicity, and to produce substances with antibacterial activity against some pathogens.
The aim of the work was the isolation and identification of lactobacilli of human origin. It was also deepened the study of their amensalistic properties, with particular attention to the resistance to gastrointestinal transit and their antagonism against pathogenic microorganisms.
Three hundred fifty-nine lactobacilli strains were isolated from swabs of healthy people and identified using molecular techniques based on the study of 16S rDNA. The identification of some strains was confirmed by further analysis DHPLC V1 and V3 of 16S rDNA. The strains were subjected to the evaluation of the resistance to bile salts and low pH, to the production of hydrogen peroxide and more particularly, it has been evaluated the ability to produce substances with antibacterial activity.
Finally, the attention was focused on the characterization of an active supernatant produced by an oral strain. The isolation of the substance provided chromatographic procedures such as SEC (Size Exclusion Chromatography using Sephadex 50) and SPE (Reverse Phase Chromatography using C18 column). The results were shown that the active fraction has a low molecular weight and for its chemical-physical characteristics is not a common bacteriocin, for this reason are on going further chromatographic studies using columns with increasing polarity (C4, phenyl, cyano, and amino) .
Future outlooks are focused on the identification of the molecule in question, by MALDI-TOF and ESI-TOF and then optimizing the whole process to standardize the entire method. In this way, the opportunity to bring to light new molecules will be possible, with the ultimate goal of being able to take advantage from these antibacterial substances
Lithium and age of pre-main sequence stars
No full textThe expectation to date the age of low mass pre-main sequence stars from lithium has been tested by comparing the observed lithium and the predicted abundance by evolutionary models. The test, in this thesis, has been applied on a sample of binary systems whose components have a well known mass or whose mass ratio has been exactly established. The common metallicity and the coevality of the two components of a system are strong constraints to determine the age on the basis of evolutionary codes.
To achieve reliable results, by an observational campaign, I have doubled the sample of stars presenting the necessary information for the analysis. Stellar parameters have been determined with the most precise and accurately tested techniques: high resolution spectroscopy along a very large wavelength range and numerical solution of the radiative transfer equation.
As to the evolutionary code, I have implemented FRANEC with the very accurate reaction rates as determined with the most reliable experimental technique, the Trojan Horse Method. Since for PMS stars the agreement between observed and predicted lithium abundance can be obtained just tuning the external convective efficiency, I have computed a database of models for different values of the mixing length parameter. Age determination of stars has been carried out by adopting what is nowadays believed to be the most powerful statistical method in the field, the Bayesian analysis. I have extended in an original way this statistical method from binary system with known masses to the most common double lined spectroscopic binaries
Role of the central serotonin2B receptor in the regulation of ascending dopaminergic pathways: relevance for the treatment of schizophrenia and drug addiction
No full textLorsque j ai commencé ma thèse en Neuropharmacologie, le rôle fonctionnel du récepteur serotoninergique2B (5-HT2B) central n était guère connu. En effet, peu d études avaient porté sur son impact au sein du système nerveux central. En particulier, il était établi que les récepteurs 5-HT2B, sans effet au niveau de la voie dopaminergique (DA) nigrostriée, sont capables d exercer un contrôle tonique excitateur sur l activité de la voie DA mésoaccumbale. Sur la base de cette régulation différentielle des voies DA sous-corticales, il avait été proposé que les antagonistes du récepteur 5-HT2B pourraient constituer des outils pharmacologiques pertinents pour le traitement des pathologies liées à une dysfonction du système DA et requérant une modulation indépendante des voies DA ascendantes, telles que la schizophrénie. Cependant, l effet du blocage des récepteurs 5-HT2B au niveau de la voie DA mésocorticale, laquelle joue un rôle pivot dans le bénéfice thérapeutique des antipsychotiques (APs) atypiques, n avait jamais été exploré. De plus, le blocage du récepteur 5-HT2B réduit les réponses neurochimiques et comportementales induites par l amphétamine et la 3,4-méthylènedioxyméthamphétamine, suggérant que ce récepteur pourrait également représenter une cible pharmacologique intéressante pour le traitement de l addiction. Néanmoins, la possible implication de ce récepteur dans les effets de la cocaïne, l une des drogues les plus consommées au monde, restait alors inconnue.
L objectif de cette thèse était d étudier l influence exercée par le récepteur 5-HT2B sur l activité DA basale et activée par la cocaïne, afin d évaluer le potentiel thérapeutique de ce récepteur dans le traitement de la schizophrénie et de l addiction. A cette fin, nous avons étudié les effets de deux antagonistes puissants et sélectifs du récepteur 5-HT2B (RS 127445 et LY 266097) sur l activité DA, en utilisant des approches biochimiques, électrophysiologiques et comportementales chez le rat.
Un premier groupe d expériences a mis en évidence l existence d un contrôle tonique inhibiteur exercé par le récepteur 5-HT2B sur la libération de DA dans le cortex préfrontal médian (CPFm). Ce résultat, démontrant que les récepteurs 5-HT2B régulent de manière différentielle les trois voies DA ascendantes, indique que les antagonistes du récepteur 5-HT2B présentent un profil d action idéale pour restaurer une fonction DA normale chez les patients schizophrènes. De plus, les antagonistes 5-HT2B se révèlent efficaces dans plusieurs modèles classiquement utilisés pour prédire l efficacité des APs, alors qu ils n ont pas d effet dans une tâche comportementale prédisant la tendance des APs à induire des effets secondaires moteurs. Un second groupe d expériences visant à étudier les mécanismes sous-tendant le contrôle différentiel exercé par le récepteur 5-HT2B sur l activité DA montre que les effets opposés induits par les antagonistes 5-HT2B sur la libération de DA dans le CPFm et le noyau accumbens (NAc) résultent d une interaction fonctionnelle avec les récepteurs 5-HT1A exprimés dans le CPFm. Enfin, le blocage du récepteur 5-HT2B supprime l hyperlocomotion provoquée par la cocaïne. Cet effet, qui se produit indépendamment de la libération de DA dans le NAc et le striatum, où l activité DA est liée aux effets comportementaux induits par la cocaïne, implique une interaction post-synaptique dans les régions DA sous-corticales.
En conclusion, le travail accompli au cours des quatre années passées apporte des informations substantielles quant au rôle fonctionnel du récepteur 5-HT2B dans la régulation des voies DA ascendantes. En outre, l ensemble de nos résultats permet non seulement d améliorer la compréhension de l interaction des systèmes DA et 5-HT, mais aussi de mettre en avant le potentiel thérapeutique des antagonistes du récepteur 5-HT2B pour le traitement de la schizophrénie et de l addiction à la cocaïne
Analysis of cerebrospinal pulse wave amplitude and correlation with optic disc morphology in Idiopathic Intracranial Hypertension
No full textAims: Aims of this thesis are to evaluate the features of cerebrospinal fluid (CSF) pulse wave amplitude (pwa) of IIH by lumbar measurements of CSF pressure during intracranial pressure (ICP) monitoring, and to correlate the CSF pwa magnitude to the level of optic disc damage in patients suffering from IIH.
Methods: The thesis consists of two parts. Part I assesses the CSF pwa value in IIH by short-term (1-hour) monitoring by lumbar puncture and compared with an age-matched control group. CSF pwa values were collected with the same method of analisys in age-matched controls and IIH patients. Part II assesses optic disc morphology in the same patients by using Optic Coerence Tomography and than describes Optic disc parameters associated with raised CSF pressure and raised CSF pwa values in IIH with and without papilledema groups.
Results: We found that the 75% of IIH patients have raised CSF mean pwa as compared to control group. Of the 75% of IIH patients that presented raised CSF pwa during short-term monitoring, the 57.3% was suffering from IIHWP and the 42.7% was IIHWOP. OCT measurements collected in IIHWP patients, suffering from both raised CSF mean pressure and raised CSF mean pwa values, showed all abnormal neuroretinal parameters: rim area and thickness, cup volume and cup-to-disc ratio (C/D), retinal nerve fiber layer (RNFL). OCT measurements collected in IIHWOP patients suffering from raised CSF mean pressure, showed abnormal both rim area and thickness, cup volume and C/D, but rather normal RNFL. Furthermore, we found statistical significance when we correlated CSF mean pressure with RNFL (r=0.60, p=0.042) and CSF pwa with RNFL (r=0.77, p=0.028; Fig.3b) collected form all participants. No correlation was found for CSF opening pressure and RNFL (r=0.34; p=0.06) among patients.
Conclusions: Our data show that, during CSF short-term monitoring by lumbar access, both CSF mean pressure and CSF mean pwa are increased in IIH group if compared to control group as expression of reduced intracranial compliance. Neuroretinal structures are more damaged in IIH patients suffering from both raised CSF mean pressure and CSF mean pwa.
The lumbar CSFP pwa could be used to evaluate the intracranial compliance and the evolution of optic nerve head damage in IIH patients