Role of diet on non-alcoholic fatty liver disease: An updated narrative review

© 2015 Baishideng Publishing Group Inc. The purpose of this article review is to update what is known about the role of diet on non-alcoholic fatty liver disease (NAFLD). NAFLD is the most common cause of chronic liver disease in the developed world and is considered to be a spectrum, ranging from fatty infiltration of the liver alone (steatosis), which may lead to fatty infiltration with inflammation known as non alcoholic steatohepatitis While the majority of individuals with risk factors like obesity and insulin resistance have steatosis, only few people may develop steatohepatitis. Current treatment relies on weight loss and exercise, although various insulin-sensitizing medications appear promising. Weight loss alone by dietary changes has been shown to lead to histological improvement in fatty liver making nutrition therapy to become a cornerstone of treatment for NAFLD. Supplementation of vitamin E, C and omega 3 fatty acids are under consideration with some conflicting data. Moreover, research has been showed that saturated fat, trans-fatty acid, carbohydrate, and simple sugars (fructose and sucrose) may play significant role in the intrahepatic fat accumulation. However, true associations with specific nutrients yet to be clarified

A study on the utility of temporal derivatives and unsupervised clustering in brain-computer interfaces

Brain-computer interfaces (BCIs) rely on accurate classification of event-related potentials (ERP), a task commonly delegated to a machine-learning algorithm, which investigates features derived from the voltages (V) recorded at different scalp locations with the electro-encephalogram (EEG). The performance of the machine-learning algorithm is an area that has captured the interest of the research community. Although major advancements have been made, BCIs suffer from uncertainties that arise from assumptions such as that participants are “focused”, “still” and that no unpredictable events occurred during the recording, for example abrupt sounds or light changes. From the range of possible uses of BCIs, one of the most challenging is its adaptation to everyday life situations. Addressing both participant and environmental related influences to the EEG could enable the usage of BCIs outside the confines of the laboratory. In addition, in order to create a BCI that can act as an “enhancement” for the able-bodied requires a way to identify recurrent events without prior knowledge, thus providing the user with a way to increment the “understanding” of his BCI. Moreover, information such as location, latency and shape of recurring events could provide solid grounds for future researchers to build upon. In the thesis the above problem is challenged by investigating two main topics: assuming that the neuro-signals are additive (i.e. uncorrelated), (a) the usage of the first time derivative of V (dV) as feature regarding performance in classification of an ERP, and (b) unsupervised clustering of ERPs. Both investigations tackle the problem of mining properties of unknown neuro-signals. Theoretical investigations carried out on in each topic are performed using synthetic signals to assess the expected behaviour. Using real data from a P300 BCI mouse, both topics were evaluated; the classification performance of dV was found to be significantly better than V while evaluating a baseline for comparison. Having such a positive outcome encouraged an attempt to create a single linkage unsupervised clustering method based on statistical significance. Without knowing if an ERP was generated or not, the developed clustering algorithm, based on dV, is shown to be accurate in identifying the shape of the underlying, “unknown” ERP. For years researchers have been constructing experiments to uncover EEG events directly related to stimuli. An outcome of this research is that recurring EEG responses which might have been neglected, simply because they were not expected, are now identifiable

Molecular genetic studies on cerebrospinal fluid monoamine metabolites in psychotic patients and healthy individuals

Dopamine, serotonin and noradrenaline are the major monoamines in the human central nervous system (CNS) and following their basic pathways they are degraded to their major metabolites homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylglycol (MHPG), respectively. The cerebrospinal fluid (CSF) concentrations of the three monoamine metabolites (MM) are considered to reflect the monoamine turnover rates in the CNS, are under genetic influence and have been associated with schizophrenia. In the first part of the thesis (Studies I, II and III), 132 healthy individuals (78 men and 54 women) were included, whereas in the second part of the thesis (Studies IV and V) 74 psychotic patients (45 men and 29 women) participated. CSF samples were drawn by lumbar puncture and genomic DNA was extracted from whole blood samples for genotyping. In the first part of the thesis, we have searched for association between single nucleotide polymorphisms (SNPs) in the tryptophan hydroxylase 1 (TPH1), dystrobrevin binding protein 1 (DTNBP1) and D-amino acid oxidase activator (DAOA) genes and the CSF MM concentrations in healthy individuals in order to shed further light to the understanding of the effect of the genes on CSF MM in humans. One TPH1 SNP and one DTNBP1 SNP were found to be significantly associated with both CSF 5-HIAA and HVA, giving evidence for association between the genes and dopamine and serotonin turnover rates in CNS. Two DAOA SNPs were significantly associated with CSF HVA concentrations, proposing that the DAOA gene is implicated in dopaminergic mechanisms. In the second part of the thesis, we searched for association between genes implicated in dopamine, serotonin and noradrenalin metabolism (Study IV) and glutamate-related genes (Study V) and CSF MM concentrations in psychotic patients. Several nominal associations and one significant association between MAOB and MHPG in men (Study IV) were found, suggesting that CSF MM concentrations can be considered as psychosis intermediate phenotypes in previously reported associations between gene variants and the disorder

Aspects of multi-national transportation investment planning

Thesis (Civ.E)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1981MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.Bibliography: leaves 126-129.by Dimitrios Andreou Tsamboulas.Civ.

Preliminary evaluation for road network improvement alternatives in less developed countries.

Thesis. 1975. M.S.--Massachusetts Institute of Technology. Dept. of Civil Engineering.Includes bibliographical references.M.S

Obese Children with Metabolic Syndrome Have 3 Times Higher Risk to Have Nonalcoholic Fatty Liver Disease Compared with Those without Metabolic Syndrome

Copyright © 2017 Dimitrios Papandreou et al. Background: The aim of this study was to investigate the relationship between metabolic syndrome (MS) and nonalcoholic fatty liver disease (NAFLD) in obese children. One hundred and twenty-five subjects aged 11-12 years old participated in the study. Methods: Anthropometric and biochemical indices were measured, including lipid and liver profile, blood glucose, serum insulin, and liver ultrasound. Results: Forty-four children (58.6%) were found to have MS. Insulin resistance was present in 78 (62.4%) children. Patients with MS were more likely to have NAFLD (P \u3c; 0.001). Children with NAFLD had significantly higher body mass index, waist circumference, triglycerides, fasting insulin, and lower high-density lipoprotein compared to patients with normal livers (P \u3c 0.001). Insulin resistance was significantly higher in children with NAFLD (P \u3c; 0.001). Obese children presenting with MS were 3.01 (2.87-3.57, P \u3c 0.002) times more likely to develop NAFLD compared to those without metabolic syndrome after adjustment of cofounders. Conclusions: Obese children with MS have a higher risk of developing NAFLD. Weight management and early prevention should be the first line of treatment to prevent any possible health issues later on

Crossed products of operator spaces and applications to Harmonic Analysis of non commutative groups

Μελετάμε τα σταυρωτά γινόμενα που προκύπτουν από δράσεις τοπικά συμπαγών ομάδων σε δυϊκούς χώρους τελεστών, τα οποία γενικεύουν την κλασική κατασκευή του σταυρωτού γινομένου για δράσεις ομάδων σε άλγεβρες von Neumann. Οι μέθοδος μας στηρίζεται στις έννοιες των αλγεβρών Hopf-von Neumann και comodules, καθώς μας παρέχουν ένα φυσιολογικό πλαίσιο μελέτης φαινομένων δυϊσμού όσον αφορά δράσεις εν γένει μη αβελιανών τοπικά συμπαγών ομάδων. Παρακάτω, ακολουθεί μια σύντομη περίληψη των κυρίων αποτελεσμάτων αυτής της διατριβής. Το πρώτο κεφάλαιο αποτελεί εισαγωγή του απαραίτητου μαθηματικού υποβάθρου για την ανάπτυξη της γενικής θεωρίας ακολούθως. Συγκεκριμένα, παραθέτουμε τους βασικούς ορισμούς και ιδιότητες αναφορικά με (δυϊκούς) χώρους τελεστών και τανυστικά γινόμενα χώρων τελεστών, την έννοια της stable point-w*-σύγκλισης και τις βασικές άλγεβρες von Neumann (και Banach) που σχετίζονται με τοπικά συμπαγείς ομάδες. Στο δεύτερο κεφάλαιο, ασχολούμαστε με άλγεβρες Hopf-von Neumann και comodules τα οποία είναι και δυϊκοί χώροι τελεστών. Συγκεκριμένα, μελετάμε τις έννοιες saturated και non-degenerate comodules μιας γενικής άλγεβρας Hopf-von Neumann, καθώς και τις μεταξύ τους σχέσεις. Για παράδειγμα, αποδεικνύουμε ότι αν κάθε comodule μιας άλγεβρας Hopf-von Neumann είναι non-degenerate, τότε κάθε comodule αυτής είναι και saturated. Επίσης, δείχνουμε ότι η τελευταία συνθήκη, δηλαδή ότι μια άλγεβρα Hopf-von Neumann έχει μόνο saturated comodules (η οποία είναι εξ ορισμού αλγεβρικού χαρακτήρα), είναι ισοδύναμη με διάφορες συνθήκες προσέγγισης. Ως εφαρμογή, αποδεικνύουμε ότι μια τοπικά συμπαγής ομάδα G έχει την προσεγγιστική ιδιότητα (AP) κατά Haagerup και Kraus αν και μόνο αν κάθε saturated comodule της άλγεβρας von Neumann L(G) της ομάδας είναι non-degenerate. Στο τρίτο κεφάλαιο, μελετώνται το χωρικό και το Fubini σταυρωτό γινόμενο για δράσεις ομάδων σε δυϊκούς χώρους τελεστών, ενώ εξετάζεται και η φυσιολογική δομή comodule (δυϊκές δράσεις) με την οποία εφοδιάζονται. Αυτά τα δύο σταυρωτά γινόμενα συμπίπτουν για δράσεις ομάδων πάνω σε άλγεβρες von Neumann από το κλασικό θεώρημα Digernes-Takesaki. Ωστόσο, ενδέχεται να διαφέρουν για αυθαίρετους δυϊκούς χώρους τελεστών. Xρησιμοποιώντας θεωρία δυϊσμού για δράσεις και την γενική θεωρία των comodules, αποδεικνύουμε ότι το Fubini σταυρωτό γινόμενο για την δράση μιας ομάδας είναι το μικρότερο saturated comodule που περιέχει το αντίστοιχο χωρικό σταυρωτό γινόμενο, ενώ το δεύτερο είναι το μεγαλύτερο non-degenerate subcomodule του πρώτου. Επομένως, από τον προηγούμενο χαρακτηρισμό των ομάδων με την AP, παίρνουμε το κεντρικό μας θεώρημα, σύμφωνα με το οποίο μια τοπικά συμπαγής ομάδα G έχει την AP αν και μόνο αν το χωρικό και το Fubini σταυρωτό γινόμενο συμπίπτουν για κάθε G-δράση σε οποιονδήποτε δυϊκό χώρο τελεστών. Αυτό βελτιώνει ένα πρόσφατο αποτέλεσμα των Crann και Neufang. Τέλος, στο τελευταίο κεφάλαιο, εφαρμόζοντας την γενική θεωρία παίρνουμε μια από εννοιολογικής άποψης καλύτερη προσέγγιση ορισμένων κλάσεων διπρότυπων πάνω από τις άλγεβρες von Neumann μιας ομάδας, τα οποία αναπαρίστανται ως σταυρωτά γινόμενα δυϊκών χώρων τελεστών που δεν είναι κατ' ανάγκη άλγεβρες von Neumann. Ως αποτέλεσμα, παίρνουμε μια λιγότερο τεχνική απόδειξη ενός θεωρήματος των Ανούση-Κτάβολου-Todorov και απαντάμε σε μια ερώτηση των ιδίων συγγραφέων αναφορικά με τα ιδεώδη της άλγεβρας Fourier. Επί πλέον, επεκτείνουμε ένα αποτέλεσμα των Crann και Neufang σχετικά με L(G)-διπρότυπα στην περίπτωση που η ομάδα G ικανοποιεί μια συνθήκη a priori ασθενέστερη της AP.We study crossed products arising from actions of locally compact groups on dual operator spaces, which generalize the classical crossed product construction for group actions on von Neumann algebras. Our methods rely on the concepts of Hopf-von Neumann algebras and comodules, since they provide a very natural framework for the study of duality phenomena concerning actions of not necessarily abelian locally compact groups. Below, we give a brief summary of the main results of this thesis. The first chapter is an introduction to the mathematical background which is necessary in order to develop the general theory later. In particular, we expose some basic definitions and properties regarding (dual) operator spaces and operator space tensor products, the notion of stable point-w*-convergence and the main von Neumann (and Banach) algebras associated with locally compact groups. In the second chapter, we deal with Hopf-von Neumann algebras and comodules which are dual operator spaces. In particular, we study the concepts of saturated and non-degenerate comodules over a general Hopf-von Neumann algebra, as well as the interplay between the two notions. For instance, we prove that if a Hopf-von Neumann algebra admits only non-degenerate comodules, then it admits only saturated comodules. Also, we show that the latter, i.e. that a Hopf-von Neumann algebra admits only saturated comodules (which is by definition an algebraic concept), is equivalent to certain approximation conditions. As an application, we prove that a locally compact group G has the approximation property (AP) of Haagerup and Kraus if and only if every saturated comodule over the group von Neumann algebra L(G) is non-degenerate. In the third chapter, we study spatial and Fubini crossed products for group actions on dual operator spaces and their natural comodule structure (dual actions). These two crossed products coincide for group actions on von Neumann algebras by the classical Digernes-Takesaki theorem. However, they may be different for arbitrary dual operator spaces. Using duality theory of actions and the general theory of comodules, we prove that the Fubini crossed product of an action is the smallest saturated comodule containing the respective spatial crossed product, whereas the latter is the largest non-degenerate subcomodule of the former. Therefore, by the previous characterization of groups with the AP, we obtain our main theorem, which states that a locally compact group G has the AP if and only if the Fubini and spatial crossed products coincide for any G-action on some dual operator space. This improves a recent result of Crann and Neufang. Finally, in the last chapter, we apply the general theory in order to obtain a more conceptual perspective of certain classes of bimodules over group von Neumann algebras arising as crossed products of dual operator spaces which are not necessarily von Neumann algebras. As aresult, we obtain a less technical proof of a theorem of Anoussis-Katavolos-Todorov and we answer to a question raised by the same authors regarding the Fourier algebra and its ideals. Also, we extend a result of Crann and Neufang concerning L(G)-bimodules when the group G satisfies a condition a priori weaker than the AP