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61.
Romina Romaniello Ludovica Pasca Elena Panzeri Fulvio DAbrusco Lorena Travaglini Valentina Serpieri Sabrina Signorini Chiara Aiello Enrico Bertini Maria Teresa Bassi Enza Maria Valente Ginevra Zanni Renato Borgatti Filippo Arrigoni 《International journal of molecular sciences》2022,23(12)
The inositol 1,4,5-triphosphate receptor type 1 (ITPR1) gene encodes an InsP3-gated calcium channel that modulates intracellular Ca2+ release and is particularly expressed in cerebellar Purkinje cells. Pathogenic variants in the ITPR1 gene are associated with different types of autosomal dominant spinocerebellar ataxia: SCA15 (adult onset), SCA29 (early-onset), and Gillespie syndrome. Cerebellar atrophy/hypoplasia is invariably detected, but a recognizable neuroradiological pattern has not been identified yet. With the aim of describing ITPR1-related neuroimaging findings, the brain MRI of 14 patients with ITPR1 variants (11 SCA29, 1 SCA15, and 2 Gillespie) were reviewed by expert neuroradiologists. To further evaluate the role of superior vermian and hemispheric cerebellar atrophy as a clue for the diagnosis of ITPR1-related conditions, the ITPR1 gene was sequenced in 5 patients with similar MRI pattern, detecting pathogenic variants in 4 of them. Considering the whole cohort, a distinctive neuroradiological pattern consisting in superior vermian and hemispheric cerebellar atrophy was identified in 83% patients with causative ITPR1 variants, suggesting this MRI finding could represent a hallmark for ITPR1-related disorders. 相似文献
62.
Dr. Sabina Yasmin Dr. Carmen Cerchia Dr. Vishnu Nayak Badavath Dr. Antonio Laghezza Prof. Fabrizio Dal Piaz Dr. Susanta K. Mondal Dr. Özlem Atlı Dr. Merve Baysal Dr. Sankaran Vadivelan Dr. S. Shankar Dr. Mohd Usman Mohd Siddique Dr. Ashok Kumar Pattnaik Dr. Ravi Pratap Singh Prof. Fulvio Loiodice Dr. Venkatesan Jayaprakash Prof. Antonio Lavecchia 《ChemMedChem》2021,16(3):484-498
Insulin resistance is a major pathophysiological feature in the development of type 2 diabetes (T2DM). Ferulic acid is known for attenuating the insulin resistance and reducing the blood glucose in T2DM rats. In this work, we designed and synthesized a library of new ferulic acid amides (FAA), which could be considered as ring opening derivatives of the antidiabetic PPARγ agonists Thiazolidinediones (TZDs). However, since these compounds displayed weak PPAR transactivation capacity, we employed a proteomics approach to unravel their molecular target(s) and identified the peroxiredoxin 1 (PRDX1) as a direct binding target of FAAs. Interestingly, PRDX1, a protein with antioxidant and chaperone activity, has been implied in the development of T2DM by inducing hepatic insulin resistance. SPR, mass spectrometry-based studies, docking experiments and in vitro inhibition assay confirmed that compounds VIe and VIf bound PRDX1 and induced a dose-dependent inhibition. Furthermore, VIe and VIf significantly improved hyperglycemia and hyperlipidemia in streptozotocin-nicotinamide (STZ-NA)-induced diabetic rats as confirmed by histopathological examinations. These results provide guidance for developing the current FAAs as new potential antidiabetic agents. 相似文献
63.
Caterina De Vito Laura Medeghini Sonia Garruto Fulvio Coletti Ilaria De Luca Silvano Mignardi 《Ceramics International》2018,44(5):5055-5062
This study is focused on Medieval Roman heavy lead-glazed ceramics from the archaeological site of the Caesar's Forum (Rome, Italy), dated from the 10th and not beyond the first decades of the 11th century. Optical microscopy (OM), X-ray powder diffraction (XRPD), scanning electron microscopy (SEM-EDS) and electron microprobe analysis (EMPA) have been used for the archaeometric characterization of the ceramics. Petrographic analysis of the body indicated the occurrence of three petro-fabrics, mainly composed by abundant quartz, feldspars, nodules of iron oxides, rare fragments of siliceous rocks, very rare fragments of calcareous rocks, pyroxene, biotite and olivine. This mineralogical assemblage suggests that the ceramics were fired in the range 950–1050 °C, under oxidizing conditions. SEM and EMP analysis show that the ceramic body was produced with non-or moderately calcareous clays and the heavy glaze with lead oxide, silica, alumina and alkalis. The microstructure of the glaze and the relationship with the body suggest that for the production of the ceramic repertoire of the Caesar's Forum either the single or the double firing techniques were used. 相似文献
64.
The relationship between simulated and judged depth separations for pairs of probe dots on planar surface patches was examined in a series of 6 experiments. The simulated slant of the patches was varied without varying the simulated depth separation of the probe dots by varying the depth gradient orthogonal to the direction determined by the probe dots on the image plane. Judged depth separation varied with mean slant for constant simulated depth separations. When observers judged depth separations along a closed path, the integral of the signed depths did not sum to zero, as would be required in Euclidean geometry. These results are inconsistent with the view that the mapping between simulated and perceived 3-D structure is affine and indicate that, in general, the perceived structure cannot be represented in either a Euclidean space or an affine space. Moreover, these results are consistent with a first-order temporal analysis of the optic flow. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
65.
L Ventura P Leocata G Santeusiano G Coletti A Partenzi T Ventura 《Canadian Metallurgical Quarterly》1997,16(2):221-226
Interest in biodiversity has spawned international actions both political and scientific, many of which are relevant to mycologists. The political initiatives include the Convention on Biological Diversity and Biodiversity Action Plans, and the scientific: the Global Biodiversity Assessment, Species 2000, Systematics Agenda 2000 International, BioNet International, Diversitas, All Taxa Biodiversity Inventory, and Biodiversity Methods Manuals. Mycologists need to contribute to such programmes, maintain an enhance profile, and remain flexible to respond to new challenges. 相似文献
66.
Fulvio Mattivi 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1993,196(6):522-525
Some recent studies have put forward the hypothesis that the presence oftrans-resveratrol (trans-3,5,4-trihydroxystilbene) in red wine may be related to some of its therapeutic properties. A fundamental step in view of this evaluation is the development of a method for the quick, accurate and precise analysis of this compound. Sample enrichment and purification can be obtained by solid-phase extraction using reverse-phase C18 cartridges. HPLC analysis carried out by means of a photodiode-array detector, with an internal standard method, allows the detection of up to 10 g/L in wine, with a linear range between 0.6 and 300 ng injected and a precision of 3.3%. The results of the first analyses show that the concentrations oftrans-resveratrol in wines might be much higher than so far reported in the literature.
HPLC-Analyse vontrans-Resveratrol in Wein nach Fest-Phasen-Anreicherung
Zusammenfassung Nach neueren Ergebnissen kann das Vorkommen vontrans-Resveratrol (trans-3,5,4-Trihydroxystilben) in Rotweinen eine therapeutische Bedeutung haben. Eine wichtige Voraussetzung ist deshalb eine möglichst schnelle und zuverlässige Bestimmungsmethode. Für die Anreicherung und Vortrennung dieser Komponente aus Wein wurde eine Fest-Phasen-Extraktion mit C18-Umkehr-Kartuschen ausgearbeitet. Die anschließende HPLC-Analyse unter Anwendung der internen Standard-Auswertemethode und einem Dioden-Array-Detektor ermöglicht eine Bestimmung von 10 g/Ltrans-Resveratrol in Wein mit einer linearen Eichkurve von 0,6 bis 300 ng und einer Genauigkeit von 3,3%. Die Ergebnisse zeigen, daß die Resveratrol-Gehalte in Wein wesentlich (etwa zehnfach) höher sind als die bisher in der Literatur angegebenen Werte.相似文献
67.
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69.
In this paper two approaches are given for anti-windup design for nonlinear control systems with linear plants subject to limitations both in the magnitude and the rate of variation of the control input. Both approaches are based on the so-called Model Recovery Anti-Windup (MRAW) framework. The first approach is built by treating the rate + magnitude saturation as a single dynamic nonlinearity, while in the second one, the dynamic compensator dynamics is extended with extra states to treat the two saturations separately. Both approaches lead to global stability with exponentially stable plants and local stability in all other cases. For both approaches, stability and performance guarantees are proven, numerical recipes are given and the relative merits are comparatively highlighted on a simulation example. 相似文献
70.
A numerical assessment of the load bearing capacity of externally pressurized moderately thick tubes
Leone Corradi Valentino Di Marcello Lelio Luzzi Fulvio Trudi 《International Journal of Pressure Vessels and Piping》2009,86(8):525-532
The collapse behavior of cylindrical shells pressurized from outside is examined. Attention is focused on tubes of moderate thickness, as required by very deep water pipelines or some innovative nuclear power plant proposals. Their collapse is expected to be dominated by yielding but, because of the decreasing nature of the post-collapse evolution, interaction with instability is likely to be significant enough to demand consideration. At present, no quantitative assessment of such effect is available, because little study has been devoted to tubes in this thickness range.Plasticity–instability interaction is activated by imperfections and to assess their influence on a systematic numerical study is undertaken. Computations produce a meaningful measure of the collapse pressure and it is proposed that the allowable pressure be determined on its basis, by introducing a suitable safety factor. This is chosen so that results reproduce those provided by presently accepted procedures in the well explored and reliable range of medium-thin tubes. When the same factor is applied to thicker tubes, the resulting allowable pressure is significantly higher than the values suggested by codes, which apparently react to the present lack of knowledge by assuming an extremely conservative attitude. 相似文献