Aquatolide has been reisolated from its natural source, and its structure has been revised on the basis of quantum-chemical NMR calculations, extensive experimental NMR analysis, and crystallography.
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IJS, KILJ, NUK, PNG, UL, UM
Thirteen Psychotria alkaloids were evaluated regarding their interactions with enzymatic targets related with neurodegenerative diseases: acetylcholinesterase (AChE), butyrylcholinesterase (BChE), ...and monoamine oxidases (MAO-A and MAO-B). Display omitted
► Four monoterpene indole alkaloids (1–4) inhibited BChE and MAO-A by different mechanisms. ► Two quaternary-β-carboline alkaloids (12,13) inhibited AChE, BChE and MAO-A. ► Docking studies were carried out in order to understand the interactions of the active compounds with AChE, BChE and MAO-A.
Thirteen Psychotria alkaloids were evaluated regarding their interactions with acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and monoamine oxidases A and B (MAO-A and MAO-B), which are enzymatic targets related with neurodegenerative diseases. Two quaternary β-carboline alkaloids, prunifoleine and 14-oxoprunifoleine, inhibited AChE, BChE and MAO-A with IC50 values corresponding to 10 and 3.39μM for AChE, 100 and 11μM for BChE, and 7.41 and 6.92μM for MAO-A, respectively. Both compounds seem to behave as noncompetitive AChE inhibitors and time-dependent MAO-A inhibitors. In addition, the monoterpene indole alkaloids (MIAs) angustine, vallesiachotamine lactone, E-vallesiachotamine and Z-vallesiachotamine inhibited BChE and MAO-A with IC50 values ranging from 3.47 to 14μM for BChE inhibition and from 0.85 to 2.14μM for MAO-A inhibition. Among the tested MIAs, angustine is able to inhibit MAO-A in a reversible and competitive way while the three vallesiachotamine-like alkaloids display a time-dependent inhibition on this target. Docking calculations were performed in order to understand the binding mode between the most active ligands and the selected targets. Taken together, our findings established molecular details of AChE, BChE and MAO-A inhibition by quaternary β-carboline alkaloids and MIAs from Psychotria, suggesting these secondary metabolites are scaffolds for the development of multifunctional compounds against neurodegeneration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The thermal degradation of edible films based on pure sodium caseinate, whey and gelatin, and for these proteins in the presence of sorbitol as a plasticizer, was studied by thermogravimetry and ...infrared spectroscopy in nitrogen atmosphere. The presence of sorbitol significantly reduced the activation energy of the degradation of the edible protein films. This behaviour was in agreement with the decrease of the initial and maximum temperatures of degradation observed by thermogravimetry. The decrease in the thermal stability is apparently associated with the effect of sorbitol on the inter- and intramolecular hydrogen bonds of the proteins. The FTIR spectra showed that the effective degradation began at ca. 300 °C with the formation of gas products such as CO
2 and NH
3, suggesting that the reaction mechanism included at the same time the scission of the C–N, C(O)–NH, C(O)–NH
2, –NH
2 and C(O)–OH bonds of the proteins. The suggested mechanism of reaction was supported by the high values of the activation energy (
E > 100 kJ mol
−1) which are probably associated with a process that occurred by random scission of the chain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Rifaximin, with its low systemic absorption, may represent a treatment of choice for irritable bowel syndrome (IBS), mainly due to its ability to act on IBS pathogenesis, through the influence on gut ...microbiota. The aim of the present study was to assess, by biomolecular tools, the rifaximin active modulation exerted on gut microbiota of non-constipated IBS patients. Fifteen non-constipated IBS subjects were treated with 550 mg rifaximin three times a day for 14 days. Stool samples were collected before starting the treatment, at the end of it, and after a 6-week washout period. Real-time polymerase chain reaction, denaturing gradient gel electrophoresis, and next-generation sequencing were applied to all the samples to verify and quantify possible microbial fluctuations. Rifaximin treatment did not affect the overall composition of the microbiota of the treated subjects, inducing fluctuations in few bacterial groups, balanced by the replacement of homologs or complementary bacterial groups. Rifaximin appeared to influence mainly potentially detrimental bacteria, such as Clostridium, but increasing the presence of some species, such as Faecalibacterium prausnitzii. A decrease in the Firmicutes/Bacteroidetes ratio after 14 days of treatment and bacterial profiles with higher biodiversity were observed during the follow-up compared to baseline. Rifaximin treatment, although effective on IBS symptom relief and normalization of lactulose breath test, did not induce dramatic shifts in the microbiota composition of the subjects, stimulating microbial reorganization in some populations toward a more diverse composition. It was not possible to speculate on differences of fecal microbiota modification between responders vs nonresponders and to correlate the quali-/quantitative modification of upper gastrointestinal microbiota and clinical response.
Provider: - Institution: - Data provided by Europeana Collections- 1401-1600. Antiche segnature: Cicogna CCXXXIV. Autore: Soldi, Cristoforo <m. 1468> (ABI I 919, 251-252). Bibliografia non a stampa: ...E.A. Cicogna, Catalogo dei codici della Biblioteca di Emmanuele Cicogna, 1841-1867, Venezia, Biblioteca del Museo Correr (già mss. Cicogna 4424-4430), 1, c. 100v. Fonti: Archivio Biografico Italiano, München 1987-. Fondo: Cicogna. Catalogazione: digitalizzazione bibliografia non a stampa. Data creazione scheda: 6 febbraio 2007. Data ultima modifica: 5 gennaio 2008.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
This paper provides a synthetic and comprehensive overview on environmentally friendly anticorrosive polymeric coatings. Firstly, the economic and environmental impact of corrosion is presented to ...highlight the need of anticorrosive polymeric coatings as a flexible and effective solution to protect a metal. Secondly, the implementation of regulations together with the consumer awareness for environmental considerations and protection of health are the driving force for a progressive but significant change in the sector. Therefore, within the protective organic coatings market, this article provides a review of the most recent developments in environmentally friendly solutions, including bio-based and water-borne epoxy, hyperbranched polyester for low- volatile organic compounds (VOC) coatings, waterborne polyurethane and non-isocyanate polyurethanes (NIPUs), and graphene or bio-based fillers for acrylics. Moreover, this paper outlines new trends such as smart additives, bio-based corrosion inhibitors, and functional antibiocorrosive coatings as superhydrophobics. Finally, industrially relevant applications of environmentally friendly anticorrosive polymeric coatings including solutions for marine and off-shore industries are summarized.
Context. Blazars are the most luminous and variable active galactic nuclei (AGNs). They are thus excellent probes of accretion and emission processes close to the central engine. Aims. We concentrate ...here on PKS 1510–089 (z = 0.36), a blazar belonging to the flat-spectrum radio quasar subclass, an extremely powerful gamma-ray source and one of the brightest in the Fermi-LAT catalog. We aim to study the complex variability of this blazar’s bright multiwavelength spectrum, to identify the physical parameters responsible for the variations and the timescales of possible recurrence and quasi-periodicity at high energies. Methods. The blazar PKS 1510–089 was observed twice in hard X-rays with the IBIS instrument onboard INTEGRAL during the flares of Jan. 2009 and Jan. 2010, and simultaneously with Swift and the Nordic Optical Telescope (NOT), in addition to the constant Fermi monitoring. We also measured the optical polarization in several bands on 18 Jan. 2010 at the NOT.Using these and archival data we constructed historical light curves at gamma-to-radio wavelengths covering nearly 20 yr and applied tests of fractional and correlated variability. We assembled spectral energy distributions (SEDs) based on these data and compared them with those at two previous epochs, by applying a model based on synchrotron and inverse Compton radiation from blazars. Results. The modeling of the SEDs suggests that the physical quantities that undergo the largest variations are the total power injected into the emitting region and the random Lorentz factor of the electron distribution cooling break, that are higher in the higher gamma-ray states. This suggests a correlation of the injected power with enhanced activity of the acceleration mechanism. The cooling likely takes place at a distance of ~1000 Schwarzschild radii(~0.03 pc) from the central engine – a distance muchsmaller than the broad line region (BLR) radius.The emission at a few hundred GeV can be reproduced with inverse Compton scattering of highly relativistic electrons off far-infrared photons if these are located much farther than the BLR, that is, around 0.2 pc from the AGN, presumably in a dusty torus. We determine a luminosity of the thermal component due to the inner accretion disk of Ld ≃ 5.9 × 1045 erg s-1, a BLR luminosity of LBLR ≃ 5.3 × 1044 erg s-1, and a mass of the central black hole of MBH ≃ 3 × 108 M⊙.The fractional variability as a function of wavelength follows the trend expected if X- and gamma-rays are produced by the same electrons as radio and optical photons, respectively.Discrete correlation function (DCF) analysis between the long-term Steward observatory optical V-band and gamma-ray Fermi-LAT light curves yields a good correlation with no measurable delay. Marginal correlation where X-ray photons lag both optical and gamma-ray ones by time lags between 50 and 300 days is found with the DCF.Our time analysis of the RXTE PCA and Fermi-LAT light curves reveals no obvious (quasi-)periodicities, at least up to the maximum timescale (a few years) probed by the light curves, which are severely affected by red noise.
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FMFMET, NUK, UL, UM, UPUK
The recent emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led society to live with a serious public health problem. In this sense, repositioning of antiretrovirals has ...captured the attention of the scientific community. Tenofovir disoproxil fumarate (TDF) is an antiretroviral compound that is used to treat acquired immune deficiency syndrome (AIDS) and hepatitis B. In this short report, we present a scale-up investigation of TDF by in situ infrared spectroscopy monitoring and a forced degradation study to describe a new degradation product. Finally, we have evaluated TDF in vitro for SARS-CoV-2 for the first time foreseeing the using of this medicine in pre-clinical and clinical investigations for the COVID-19 (coronavirus disease 2019) treatment.
Although only a subset of smokers develop lung cancer, we cannot determine which smokers are at highest risk for cancer development, nor do we know the signaling pathways altered early in the process ...of tumorigenesis in these individuals. On the basis of the concept that cigarette smoke creates a molecular field of injury throughout the respiratory tract, this study explores oncogenic pathway deregulation in cytologically normal proximal airway epithelial cells of smokers at risk for lung cancer. We observed a significant increase in a genomic signature of phosphatidylinositol 3-kinase (PI3K) pathway activation in the cytologically normal bronchial airway of smokers with lung cancer and smokers with dysplastic lesions, suggesting that PI3K is activated in the proximal airway before tumorigenesis. Further, PI3K activity is decreased in the airway of high-risk smokers who had significant regression of dysplasia after treatment with the chemopreventive agent myo-inositol, and myo-inositol inhibits the PI3K pathway in vitro. These results suggest that deregulation of the PI3K pathway in the bronchial airway epithelium of smokers is an early, measurable, and reversible event in the development of lung cancer and that genomic profiling of these relatively accessible airway cells may enable personalized approaches to chemoprevention and therapy. Our work further suggests that additional lung cancer chemoprevention trials either targeting the PI3K pathway or measuring airway PI3K activation as an intermediate endpoint are warranted.
Abstract
The readout electronics for the CMS electromagnetic calorimeter is undergoing a re-design in order to cope with the LHC ugrade. In particular, a fourfold increase in the sampling frequency ...(from 40 to 160 MS/s) is required. Therefore a new readout ASIC has been developed. The ASIC, named LiTE-DTU, is designed in a CMOS 65 nm technology. The LiTE-DTU embeds two 12 bit, 160 MS/s ADCs, a time window based sample selection, lossless data compression and 1.28 Gb/s serialization. An on-chip PLL provides the 1.28 GHz clock required by the ADCs and the serializers from the 160 MHz clock.
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