511 research outputs found
The unexpected influencer: Pope Francis and European perceptions of the recent refugee crisis
No full textThis article analyses the impact of non-informative communication on Europeans' perceptions of European Union (EU) action on the issue of migration. We exploit the fact that Pope Francis's visit to Lesbos Island in 16 April 2016, overlaps with the days of the interviews for a Special Eurobarometer survey, such that some respondents were unintentionally exposed to the Pope's speech while others were not. Comparing Catholics and non-Catholics before and after the Pope's visit in a difference-in-differences setting, we show that the papal message persuaded exposed Catholic individuals that EU action on the issue of migration is insufficient. The effect is temporary and varies according to the demographic characteristics of the respondents and by the country's share of asylum applicants in 2015. Moreover, media exposure of the Pope's visit, measured by the Global Database of Events, Language, and Tone, was greater in Catholic countries, and this might explain the effect found
DOWN-REGULATION OF HEPATIC MBOAT7 BY HYPERINSULINEMIA FAVORS STEATOSIS DEVELOPMENT
No full textBackground and aims: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver diseases in Western Countries. NAFLD could evolve into nonalcoholic steatohepatitis (NASH), which is associated with activation of fibrogenesis, possibly leading to cirrhosis and hepatocellular carcinoma (HCC). The genetic background plays a pivotal role in predisposing to development and progression of liver disease. Recently, our group have shown that the rs641738 C>T variant, in the Membrane bound o-acyltransferase domain-containing 7 locus (MBOAT7), increases the risk of NAFLD, NASH and fibrosis, by decreasing the hepatic expression of MBOAT7, a protein involved in phosphatidylinositol acyl-chain remodeling. Aim of this study was to evaluate the regulation of hepatic MBOAT7 and the impact on hepatic fat accumulation.
Methods: We examined hepatic and adipose MBOAT7 expression in 119 obese patients and in experimental models. We silenced hepatic Mboat7 by i.v. administration of antisense oligonucleotides modified by morpholinos (MPO) for 4 consecutive days in C57Bl/6 male mice (n=6).
Results: In obese patients, hepatic mRNA levels of MBOAT7 progressively decreased from normal liver to simple steatosis and NASH (p<0.05). At multivariate analysis, type 2 diabetes (p<0.05), necroinflammation (p<0.01) and MBOAT7 genotype (p<0.01) were independently associated with MBOAT7 down-regulation. This suggests that down-regulation of hepatic MBOAT7 is involved in NAFLD pathogenesis independently of MBOAT7 genotype. In line with this hypothesis, we found that mRNA and protein levels of Mboat7 were reduced in experimental models of NAFLD: in the methionine-choline deficient diet (MCD), but more so in genetically obese Lepob/ob mice and in insulin resistant mice with Insulin receptor haplo-insufficiency (InsR+/-), characterized by hyperinsulinemia (p<0.05). Furthermore, in wild-type male mice Mboat7 was physiologically down-regulated by refeeding concomitantly with the rise of insulin levels and activation of hepatic insulin signaling through Phosphatidyl Inositol 3-Kinase (PI3K) and the Serine/Threonine Kinase AKT. In keeping with these results, activation of insulin-receptor dependent signaling down-regulated Mboat7 protein expression in primary mouse hepatocytes in a PI3Kinase-depedent manner. Consistently, in InsR+/- hepatocytes insulin-mediated suppression of Mboat7 was lost (p<0.01). Moreover, the effect of insulin on Mboat7 expression was also abrogated in wild-type hepatocytes treated with antisense oligonucleotide stabilized by morpholination directed against FoxO1 (MPO) (p<0.05). These data suggest that FoxO1 is required to mediate the Mboat7 regulation by insulin. Consistently with this notion, the hampered Mboat7 expression observed in InsR+/- hepatocytes was rescued by FoxO1-silencing by antisense-MPO (p<0.05 vs scramble). Finally, in vivo administration of antisense-MPO against Mboat7 for 4 consecutive days, induced a 45% silencing of hepatic Mboat7 in wild-type male mice, which is comparable to that associated with the genetic risk variant, resulting in 80% increase in hepatic TG content (p<0.05 vs scramble) and in microvesicular steatosis development. In contrast, it did not affect circulating glucose, insulin and lipid levels. Steatosis development was not explained by altered de novo lipogenesis or β-oxidation or VLDL export, but was associated with increased expression of fatty acids transporters (such as Fatp1, Fabp1). Conversely, Mboat7 silencing was not associated with alterations in the hepatic expression of inflammatory cytokines and chemokines (such as Tnf-α and Cxcl10). These data are consistent with human genetic data suggesting that MBOAT7 down-regulation plays a causal role in NAFLD development.
Conclusion: In summary, we found that hyperinsulinemia, a typical feature of metabolic syndrome and post-prandial conditions, reduces hepatic MBOAT7 expression via increased insulin signaling activation through the Insulin receptor - PI3K – FoxO1 pathway. Reduced MBOAT7 then favors hepatic fat accumulation. These data suggest that MBOAT7 down-regulation may be implicated in the pathogenesis of progressive NAFLD
Sol-gel synthesis of CaTiO3:Pr3+ red phosphors : tailoring the synthetic parameters for luminescent and afterglow applications
No full textTwo sol-gel synthetic routes for the preparation of CaTiO3: Pr3+ red emitting phosphors were compared, with the aim of producing nanostructured materials with tailored luminescence/afterglow properties. The effect of the synthetic parameters, such as the addition of a stabilizer and calcination temperature, on the structural, morphological, and optical properties was investigated. The desired perovskite phase was obtained at a calcination temperature of 800 degrees C or higher. Although the use of acetic acid as the chelating agent leads to micrometric particles with heterogeneous composition, the presence of hydroxypropylcellulose (HPC) results in smaller, less aggregated particles as well as in a high phase purity. At the highest HPC content, surface Ca-rich impurities were detected, although no segregated Ca-rich phases were detectable by X-ray powder diffraction analyses. Luminescence properties were found to be positively related to the phase purity of the oxide, with the highest quantum yields at temperatures equal to or higher than 1000 degrees C. On the contrary, persistent luminescence properties were highest at intermediate calcination temperatures and for samples synthesized with acetic acid. Overall, a notable role of oxygen vacancies resulting from local Ca excess was observed, acting as trap levels promoting longer relaxation pathways. Thanks to the small-sized particles and best steady-state luminescent properties due to a substantial decrease of lattice defects, the HPC synthesis is a promising strategy for light-emitting diode applications. On the other hand, the acetic acid synthesis promoted a higher defect density, which is required for an efficient yield of light emission in the long time range and is thus more suitable for afterglow applications
Numerical models of a beam belonging to a tall building: errors and approximations within ordinary design
No full textThis paper is based on some students’ projects developed within the 2012 Course of Mathematical Models in Architecture and Numerical Analysis, at Architecture of Building School, Politecnico di Milano. It deals with several models of a beam belonging to a residential tall building floor. Assuming that every existing structure can be analyzed by a more or less extended models (completeness) with different accuracy (concreteness), the model provided points out roughly solutions. Progressively improving the easiest model, the relevance of modelling hypotheses used within structural design is proved. Structural analysis was performed by an useful and educational software
tool: ADINA900
Understanding Solid–Gas Reaction Mechanisms by Operando Soft X-Ray Absorption Spectroscopy at Ambient Pressure
No full textAmbient-pressure operando soft X-ray absorption spectroscopy (soft-XAS) was applied to study the reactivity of hydroxylated SnO2 nanoparticles toward reducing gases. H2 was first used as a test case, showing that the gas phase and surface states can be simultaneously probed: Soft-XAS at the O K-edge gains sensitivity toward the gas phase, while at the Sn M4,5-edges, tin surface states are explicitly probed. Results obtained by flowing hydrocarbons (CH4 and CH3CHCH2) unequivocally show that these gases react with surface hydroxyl groups to produce water without producing carbon oxides and release electrons that localize on Sn to eventually form SnO. The partially reduced SnO2 – x layer at the surface of SnO2 is readily reoxidized to SnO2 by treating the sample with O2 at mild temperatures (>200 °C), revealing the nature of “electron sponge” of tin oxide. The experiments, combined with DFT calculations, allowed devising of a mechanism for dissociative hydrocarbon adsorption on SnO2, involving direct reduction of Sn sites at the surface via cleavage of C–H bonds and the formation of methoxy- and/or methyl-tin species at the surface
Clinical Performance, Patient Reported Outcome, and Radiological Results of a Short, Tapered, Porous, Proximally Coated Cementless Femoral Stem : Results up to Seven Years of Follow-Up
No full textBackground: The primary aim of our study was to assess clinical performance, patient reported outcome and radiological results of cementless primary total hip arthroplasty using Tri-Lock Bone Preservation Stem. Methods: Between March 2010 and June 2012, 163 consecutive patients, were enrolled in the study. Patients were assessed clinically and radiographically prior to surgery as well as at 6, 12, 24 months and then at 5, 6, and 7 years postoperatively. Results: Using the Dorr classification, 39 patients (23.9%) were classified as Dorr A, 116 patients (71.2%) as Dorr B, and 8 patients (4.9%) as Dorr C. A total of 139 patients (85.3%) received a high offset, whereas 24 patients (14.7%) received a standard offset stem. Total Harris Hip Score of the patients increased from a mean of 27.29 (±4.6) preoperatively, upto 97.28 (±9.0) after 5 years. Mean preoperative Short Form-12 (SF-12) Physical Health Composite Scale score was 27.31 (±3.8). After 5 year was 55.3 (34-57). The mean preoperative SF-12 Mental Health Composite Scale score was 57.02 (±5.9). After 5 year was 59.3 (28.7-60.8). Only one patient underwent revision surgery for dislocation and revision of the head. Conclusion: Tri-lock Bone Preservation Stem DePuy proved to be an easy-to-use device. Results obtained up to 7 years of FU show excellent clinical performance, as well as radiographic osseointegration, with no cases of aseptic loosening and no images of progressive radiolucent lines or periprosthetic osteolysis
Serum Cytokine Profile by ELISA in Patients with Echinococcal Cysts of the Liver: A Stage-Specific Approach to Assess Their Biological Activity
No full textTo investigate the usefulness of serum cytokine dosage in the clinical management of cystic echinococcosis (CE), we analyzed serum levels of Th1 and Th2 cytokines in patients with hepatic CE in different cyst stages, CE1-2 (active), CE3a-3b (transitional), and CE4-5 (inactive). Ex vivo assessment of Th1 (IFN-γ) and Th2 (IL-4, IL-13, and IL-10) cytokines in sera was carried out using ELISA. IL-10 was undetectable in all serum samples of patients and controls, while a few sera contained measurable amounts of IFN-γ, IL-4, and IL-13. No statistically significant difference was found between the percentages of positive samples for each cytokine and the different groups analyzed (patients/controls, stage, number, location, and size of the cyst, serology, and sex of patients), with the exception of the association of IL-4 and IL-13 with the cyst stage. Overall, this investigation showed many limits of serum cytokine dosage as a marker of biological activity of echinococcal cysts. Because of low sensitivity and lack of specificity of this test, we believe that other ways to evaluate ex vivo biological activity of the cysts should be explored
Effective nocturnal oxygen therapy increases circulating level of tumor necrosis factor-[alpha] in heart failure
No full textOBJECTIVES: Tumor necrosis factor (TNF)-α is elevated in chronic heart failure (CHF). The cause of this increase is not well known. Several hypotheses have been investigated. Previous experimental and clinical studies detected changes in TNF circulating levels related to arterial oxygen (O2) saturation. The aim of the present study was to evaluate whether standard O2 hospital therapy affects plasma concentration of TNF-α in stable CHF patients. METHODS: A total of 18 patients (New York Heart Association class II and III) were enrolled and randomly assigned to two different orders of treatment: nine patients underwent a first night of O2 applied by nasal prongs and a second night of air delivered by nasal prongs, whereas the other nine patients were assigned to the contrary order of treatments (i.e. first night with air and second night with O2) in a crossover design. RESULTS: Ten patients out of 18 had O2 saturation above 95% for at least 360 min. In these ten patients, the TNF-α plasma level increased after O2 compared to the basal condition (delta 5.47 ± 1.72 pg/ml; P < 0.05) whereas, in the same patients, the TNF-α plasma level did not change after the night with air (delta -0.05 ± 3.03 pg/ml). A linear positive correlation (r = 0.62, P < 0.01) between minutes of O2 saturation above 95% and TNF-α circulating differences from basal to post-O2 therapy was found. CONCLUSIONS: Effective nocturnal hospital O2 therapy affects TNF-α plasma levels and the increase of TNF-α appears to be linearly related to the time of blood O2 saturation above 95%
An investigation on the bulk and surface properties of Ta-doped TiO2 nanomaterials
No full textINTRODUCTION
Titanium dioxide is a widely adopted compound in the field of nanomaterials for manifold applications, such as production of green fuels, water splitting, solar cells, drug delivery systems, surface functionalization and photocatalysis [1-2]. The doping with metal species was variously proposed as a possible technique able to vary the structural, electronic and surface properties and also to increase the performance of the TiO2 nanopowders [3]. Recently, we studied tantalum doping of TiO2 as a possible procedure for enhancing TiO2 activity under UV irradiation [4]. In fact, theoretical studies expected tantalum to improve the photocatalytic performance of TiO2 by providing additional free electrons (thanks to the higher oxidation state of Ta with respect to Ti) and energy states available for excitation in the conduction band [4]. Nonetheless, to the best of our knowledge, an in-depth study able to correlate the modification of the lattice provided by Ta dopant with the modification of the TiO2 surface properties, for differently synthesized TiO2 nanopowders, is not present in the literature yet.
In the present work, different sol-gel procedures permitted to synthesize titania samples with a different phase composition (pure anatase and anatase / brookite mixtures). Corresponding Ta-doped samples were prepared. The influence of the synthetic procedure and of the effect of Ta addition were investigated by means of a wide variety of characterizations. The synthesized nanomaterials were then adopted as photocatalysts in the degradation of the active principle of the bestseller on the- count (OTC) drug in Italy, that is acetaminophen (paracetamol), which in the last few years has become an important emerging pollutant of water bodies due to its extensive use.
EXPERIMENTAL
Material Synthesis. The TiO2 samples were synthesized by sol-gel syntheses. The doping with Ta was provided by an impregnation method, in which the amorphous TiO2 powder is suspended in a TaCl5 ethanol/water solution.
Finally, a thermal treatment at 400 °C was performed.
Material Characterization. The nanopowders were characterized by XRPD and BET specific surface area analyses in order to investigate the structural and the morphological properties (phase composition, crystallite dimension, porosity). Further analyses allowed to get information about the active site properties in terms of surface acidity and hydroxylation by adsorption /
desorption of a probe molecule (phenylethylamine). HRTEM was used to discuss the presence of different titania phases and tantalum moieties. Granulometry analyses and suspension stability tests were also performed.
Photocatalytic tests. The undoped and Ta-doped samples were tested in the photodegradation of acetaminophen, under UV irradiation, both concerning the disappearance and the final mineralization of the molecule. The photocatalytic tests were performed also in the presence of OḢ• and h+ scavenger compounds (i-propanol and EDTA), in order to evaluate the role of these oxidizing species in the reaction route.
RESULTS AND DISCUSSION
Structural characterization by XRPD of the differently synthesized samples revealed different phase compositions. The addition of acetic acid in the reaction environment promoted anatase growth, avoiding brookite formation. Ta inclusion slightly modified the phase composition, while the morphology of the nanomaterials was deeply affected by synthesis and doping procedures.
CONCLUSION
Ta-doped TiO2 nanomaterials were synthesized according to different synthetic routes. The effect of the dopant on anatase and anatase / brookite systems was investigated. Bulk, surface and photocatalytic properties (even in the presence of scavengers) were studied in order to provide a comprehensive analysis on these compounds, thus enlightening their perspective use for different applications where a superior activity under UV irradiation is needed.
REFERENCES
1. X. Chen et al., Chem. Rev. 107, 2891 (2007)
2. G. Soliveri et al., J. Phys. Chem. C 116, 26405 (2012)
3. O. Carp et al., Prog. Solid State Chem. 32, 33 (2004)
4. L. Rimoldi et al., J. Phys. Chem. C 19, 24104 (2015
Factors Influencing the Serological Response in Hepatic Echinococcus granulosus Infection
No full textKnowledge of variables influencing serology is crucial to evaluate serology results for the diagnosis and clinical
management of cystic echinococcosis (CE). We analyzed retrospectively a cohort of patients with hepatic CE
followed in our clinic in 2000–2012 to evaluate the influence of several variables on the results of commercial
enzyme-linked immunosorbent assay (ELISA) and indirect hemagglutination (IHA) tests. Sera from 171 patients
with 1 hepatic CE cyst, and 90 patients with nonparasitic cysts were analyzed. CE cysts were staged according to
the WHO-IWGE classification and grouped by activity. A significant difference in ELISA optical density (OD)
values and percentage of positivity was found among CE activity groups and with controls (P < 0.001). The
serological response was also influenced by age (P < 0.001) and cyst number (P = 0.003). OD values and cyst size
were positively correlated in active cysts (P = 0.001). IHA test showed comparable results. When we analyzed the
results of 151 patients followed over time, we found that serology results were significantly influenced by cyst
activity, size, number, and treatment 12 months before serum collection. In conclusion, serological responses as
assessed by commercial tests depend on CE cyst activity, size and number, and time from treatment. Clinical studies
and clinicians in their practice should take this into account
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