1,128 research outputs found

    Morphometrische Analyse der retinalen Ganglienzellen in der menschlichen Netzhaut

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    Ziel dieser Studie war es, mit neuroanatomischen Verfahren der FluoreszenzfĂ€rbung retinale Ganglienzellen retrograd anzufĂ€rben, um sie zu beschreiben und zu klassifizieren. Dies ist wichtig, weil GZ bei verschiedenen Erkrankungen mit einer Degeneration reagieren. Es wurden 1-2 Tage post mortem entnommene Retinae nach AnfĂ€rbung mit DiI fĂŒr mehrere Monate bei Raumtemperatur aufbewahrt. Einzelne „komplett“ angefĂ€rbte GZ wurden fluoreszenzmikroskopisch aufgenommen. Eine Klassifizierung der GZ erfolgte aufgrund ihrer: Morphologie, GrĂ¶ĂŸe, Dendritenposition und -anzahl sowie Lokalisation. Die RGZ zeigten eine aufschlussreiche morphologische VielfĂ€ltigkeit. Die Midgetzellen und die Parasolzellen konnten u.a. identifiziert, unterklassifiziert und morphometrisch ausgewertet werden. Hiernach wurde festgestellt, dass diese Technik der FluoreszenzfĂ€rbung allein nicht geeignet ist, aussagekrĂ€ftige RĂŒckschlĂŒsse ĂŒber degenerierte GZ infolge bestimmter Erkrankungen zu machen

    Highly-accessible, doped TiO<sub>2</sub> nanoparticles embedded at the surface of SiO<sub>2</sub> as photocatalysts for the degradation of pollutants under visible and UV radiation

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    A series of photocatalysts consisting of C- and N-doped titanium dioxide (TiO2) nanoparticles highly dispersed and firmly embedded at the surface of a silica matrix were prepared using a novel synthesis method in which activated carbon has a double role: it acts as support for depositing the TiO2 nanoparticles and as hard template for generating a silica matrix that embeds them. Additionally, the use of activated carbon in combination with ammonia during the synthesis led to carbon and nitrogen doping of the TiO2 domains, which enhanced their absorption of radiation in the visible range. The combination of these features led to higher activity (i.e. higher removal % and TON) in the photocatalytic degradation of probe pollutants (phenol and rhodamine B) compared to the benchmark P25 TiO2 under UV and, even more markedly, under visible radiation. Particularly, the photocatalyst prepared with 10 wt% of TiO2 nanoparticles (10%TiO2NP@SiO2) displayed much enhanced TON values under visible radiation compared to P25 TiO2 (a 12 times higher TON with rhodamine B, and an 8 times higher TON with phenol). The TON values are also significantly higher compared to any previously reported TiO2-SiO2 photocatalyst. The TiO2NP@SiO2 photocatalysts can be effectively reused in consecutive runs. The photocatalytic activity of the prepared materials was correlated to their physicochemical properties by means of a thorough characterisation using a combination of techniques (XRD, ICP-OES, N2 physisorption, TEM, UV–vis, FT-IR and XPS)

    Preoperative cardiac risks in noncardiac surgery: The role of coronary angiography

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    The preoperative evaluation of patients candidates to noncardiac surgery requires a knowledge of factors related both to type of surgery and to features of the single patient, potentially responsible for perioperative cardiovascular complications, fatal and nonfatal. The assessment of symptoms and/or noninvasive testing indicating the presence of coronary artery disease may suggest the need for medical therapy optimization and, eventually, coronary arteriography before the scheduled timing of noncardiac surgery. There is no evidence favoring a prophylactic myocardial revascularization (percutaneous or surgical) and more studies are needed to define the role of coronary artery disease diagnosis and treatment before high-risk non cardiac surgery

    Exploring the endocannabinoidome in genetically obese (ob/ob) and diabetic (db/db) mice: Links with inflammation and gut microbiota

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    Background: Obesity and type 2 diabetes are two interrelated metabolic disorders characterized by insulin resistance and a mild chronic inflammatory state. We previously observed that leptin (ob/ob) and leptin receptor (db/db) knockout mice display a distinct inflammatory tone in the liver and adipose tissue. The present study aimed at investigating whether alterations in these tissues of the molecules belonging to the endocannabinoidome (eCBome), an extension of the endocannabinoid (eCB) signaling system, whose functions are important in the context of metabolic disorders and inflammation, could reflect their different inflammatory phenotypes. Results: The basal eCBome lipid and gene expression profiles, measured by targeted lipidomics and qPCR transcriptomics, respectively, in the liver and subcutaneous or visceral adipose tissues, highlighted a differentially altered eCBome tone, which may explain the impaired hepatic function and more pronounced liver inflammation remarked in the ob/ob mice, as well as the more pronounced inflammatory state observed in the subcutaneous adipose tissue of db/db mice. In particular, the levels of linoleic acid-derived endocannabinoid-like molecules, of one of their 12-lipoxygenase metabolites and of Trpv2 expression, were always altered in tissues exhibiting the highest inflammation. Correlation studies suggested the possible interactions with some gut microbiota bacterial taxa, whose respective absolute abundances were significantly different between ob/ob and the db/db mice. Conclusions: The present findings emphasize the possibility that bioactive lipids and the respective receptors and enzymes belonging to the eCBome may sustain the tissue-dependent inflammatory state that characterizes obesity and diabetes, possibly in relation with gut microbiome alterations

    Robust iso-surface tracking for interactive character skinning

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    International audienceWe present a novel approach to interactive character skinning, which is robust to extreme character movements, handles skin contacts and produces the effect of skin elasticity (sliding). Our approach builds on the idea of implicit skinning in which the character is approximated by a 3D scalar field and mesh-vertices are appropriately re-projected. Instead of being bound by an initial skinning solution used to initialize the shape at each time step, we use the skin mesh to directly track iso-surfaces of the field over time. Technical problems are two-fold: firstly, all contact surfaces generated between skin parts should be captured as iso-surfaces of the implicit field; secondly, the tracking method should capture elastic skin effects when the joints bend, and as the character returns to its rest shape, so the skin must follow. Our solutions include: new composition operators enabling blending effects and local self-contact between implicit surfaces, as well as a tangential relaxation scheme derived from the as-rigid-as possible energy to solve the tracking problem

    Circulating fatty acids and endocannabinoidome-related mediator profiles associated to human longevity

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    To evaluate whether a peculiar plasma profile of fatty acids and endocannabinoidome (eCBome)-related mediators may be associated to longevity, we assessed them in octogenarians (Old; n=42) living in the east-central mountain area of Sardinia, a High-Longevity Zone (HLZ), compared to sexagenarian (Young; n=21) subjects from the same area, and to Olds (n=22) from the Northern Sardinia indicated as Lower-Longevity Zone (LLZ). We found significant increases in conjugated linoleic acid (CLA) and heptadecanoic acid (17:0) levels in Old-HLZ with respect to younger subjects and Old-LLZ subjects. Young-HLZ subjects exhibited higher circulating levels of pentadecanoic acid (15:0) and retinol. Palmitoleic acid (POA) was elevated in both Young and Old subjects from the HLZ. eCBome profile showed a significantly increased plasma level of the two endocannabinoids, N-arachidonoyl-ethanolamine (AEA) and 2-arachidonoyl-glycerol (2-AG) in Old-HLZ subjects compared to Young-HLZ and Old-LLZ respectively. In addition, we found increased N-oleoyl-ethanolamine (OEA), 2-linoleoyl-glycerol (2-LG) and 2-oleoyl-glycerol (2-OG) levels in Old-HLZ group with respect to Young-HLZ (as for OEA an d 2-LG) and both the Old-LLZ and Young-HLZ for 2-OG. The endogenous metabolite of docosahexaenoic acid (DHA), N-docosahexaenoyl-ethanolamine (DHEA) was significantly increased in Old-HLZ subjects. In conclusion, our results suggest that in the HLZ area, Young and Old subjects exhibited a favourable, albeit distinctive, fatty acids and eCBome profile that may be indicative of a metabolic pattern potentially protective from adverse chronic conditions. These factors could point to a suitable physiological metabolic pattern that may counteract the adverse stimuli leading to age-related disorders such as neurodegenerative and metabolic diseases

    Characterisation of Gut Microbiota in Ossabaw and Göttingen Minipigs as Models of Obesity and Metabolic Syndrome

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    Recent evidence suggests that the gut microbiota is an important contributing factor to obesity and obesity related metabolic disorders, known as the metabolic syndrome. The aim of this study was to characterise the intestinal microbiota in two pig models of obesity namely Göttingen minipigs and the Ossabaw minipigs.The cecal, ileal and colonic microbiota from lean and obese Osabaw and Göttingen minipigs were investigated by Illumina-based sequencing and by high throughput qPCR, targeting the 16S rRNA gene in different phylogenetic groups of bacteria. The weight gain through the study was significant in obese Göttingen and Ossabaw minipigs. The lean Göttingen minipigs' cecal microbiota contained significantly higher abundance of Firmicutes (P<0.006), Akkermensia (P<0.01) and Methanovibribacter (P<0.01) than obese Göttingen minipigs. The obese Göttingen cecum had higher abundances of the phyla Spirochaetes (P<0.03), Tenericutes (P<0.004), Verrucomicrobia (P<0.005) and the genus Bacteroides (P<0.001) compared to lean minipigs. The relative proportion of Clostridium cluster XIV was 7.6-fold higher in cecal microbiota of obese Göttingen minipigs as compared to lean. Obese Ossabaw minipigs had a higher abundance of Firmicutes in terminal ileum and lower abundance of Bacteroidetes in colon than lean Ossabaw minipigs (P<0.01). Obese Ossabaws had significantly lower abundances of the genera Prevotella and Lactobacillus and higher abundance of Clostridium in their colon than the lean Ossabaws. Overall, the Göttingen and Ossabaw minipigs displayed different microbial communities in response to diet-induced obesity in the different sections of their intestine.Obesity-related changes in the composition of the gut microbiota were found in lean versus obese Göttingen and Ossabaw minipigs. In both pig models diet seems to be the defining factor that shapes the gut microbiota as observed by changes in different bacteria divisions between lean and obese minipigs

    PROP1 and CTNNB1 expression in adamantinomatous craniopharyngiomas with or without ÎČ-catenin mutations

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    INTRODUCTION: Activating mutations in exon 3 of the &#946;-catenin gene are involved in the pathogenesis of adamantinomatous craniopharyngiomas. Recently, the interaction between &#946;-catenin and PROP1 has been shown to be responsible for pituitary cell lineage determination. We hypothesized that dysregulated PROP1 expression could also be involved in the pathogenesis of craniopharyngiomas OBJECTIVES: To determine whether dysregulated gene expression was responsible for tumor pathogenesis in adamantinomatous craniopharyngiomas, the &#946;-catenin gene was screened for mutations, and the expression of the &#946;-catenin gene and PROP1 was evaluated. &#946;-catenin gene was amplified and sequenced from 14 samples of adamantinomatous craniopharyngiomas. PROP1 and &#946;-catenin gene expression was assessed by real-time RT-PCR from 12 samples, and &#946;-catenin immunohistochemistry was performed on 11 samples. RESULTS: Mutations in the &#946;-catenin gene were identified in 64% of the adamantinomatous craniopharyngiomas samples. Evidence of &#946;-catenin gene overexpression was found in 71% of the tumors with &#946;-catenin mutations and in 40% of the tumors without mutations, and &#946;-catenin immunohistochemistry revealed a nuclear staining pattern for each of the analyzed samples. PROP1 expression was undetectable in all of the tumor samples. CONCLUSION: We found evidence of &#946;-catenin gene overexpression in the majority of adamantinomatous craniopharyngiomas, and we also detected a nuclear &#946;-catenin staining pattern regardless of the presence of a bcatenin gene mutation. These results suggest that WNT signaling activation plays an important role in the pathogenesis of adamantinomatous craniopharyngiomas. Additionally, this study was the first to evaluate PROP1 expression in adamantinomatous craniopharyngiomas, and the absence of PROP1 expression indicates that this gene is not involved in the pathogenesis of this tumor, at least in this cohort
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