IRIS Università degli Studi dell'Aquila
Not a member yet
68355 research outputs found
Sort by
Proprietà e libertà di iniziativa economica nel sindacato giurisdizionale sugli atti di pianificazione urbanistica
No full textThe reducing end of cell wall oligosaccharides is critical for DAMP activity in Arabidopsis thaliana and can be exploited by oligosaccharide oxidases in the reduction of oxidized phenolics
Get PDFThe enzymatic hydrolysis of cell wall polysaccharides results in the production of oligosaccharides with nature of damage-associated molecular patterns (DAMPs) that are perceived by plants as danger signals. The in vitro oxidation of oligogalacturonides and cellodextrins by plant FAD-dependent oligosaccharide-oxidases (OSOXs) suppresses their elicitor activity in vivo, suggesting a protective role of OSOXs against a prolonged activation of defense responses potentially deleterious for plant health. However, OSOXs are also produced by phytopathogens and saprotrophs, complicating the understanding of their role in plant-microbe interactions. Here, we demonstrate the oxidation catalyzed by specific fungal OSOXs also converts the elicitor-active cello-tetraose and xylo-tetraose into elicitor-inactive forms, indicating that the oxidation state of cell wall oligosaccharides is crucial for their DAMP function, irrespective of whether the OSOX originates from fungi or plants. In addition, we also found that certain OSOXs can transfer the electrons from the reducing end of these oligosaccharides to oxidized phenolics (bi-phenoquinones) instead of molecular O2, highlighting an unexpected sub-functionalization of these enzymes. The activity of OSOXs may be crucial for a thorough understanding of cell wall metabolism since these enzymes can redirect the reducing power from sugars to phenolic components of the plant cell wall, an insight with relevant implications for plant physiology and biotechnology
Engineered TMDs and TMTHs 2D-materials for Gas Sensing and Photoelectrocatalytic applications
No full textNanomaterials represent a significant percentage of materials science research. Among them, bidimensional (2D) materials have gained ever increasing relevance; on this account, twenty years of research and technological development of 2D materials and their applications have now passed since the discovery of Graphene in 2004.
This thesis work is focused on
(i)
the synthesis and characterization of innovative 2D materials
(ii)
their application as functional interfaces for gas sensing and photoelectrocatalysis (PEC)
(iii)
some technological aspects related to the measurement systems (i.e. the design of innovative gas sensing substrates and the setup and calibration of a photoelectrocatalysis test cell)
The bidimensional materials studied in this work belong to the families of Transition Metal Dichalcogenides (2D-TMDs) and Transition Metal Trihalides (2D-TMTHs). Regarding 2D-TMDs, by means of a variety of synthesis techniques (mainly Liquid Phase Exfoliation – LPE and Hydro-Solvothermal Growth – SG), the synthesis of 2D-SnSe2 and 2D-In2Se3, plus a 2D-SnSe2/TiO2 heterostructure have been achieved; moreover, by exploiting their spontaneous tendency towards oxidation in environmental conditions, both amorphous/crystalline 2D layered heterostructures and bidimensional layered amorphous metal oxides (hereafter named LAMOS), have been synthesized, specifically obtaining 2D a-SnO2 from controlled annealing of 2D-SnSe2 and 2D a-In2O3/In2Se3 heterostructure from controlled annealing of 2D-In2Se3. Regarding 2D-TMTHs, for the first time 2D-CrCl3 has been exfoliated by means of LPE, a high yield, industrially scalable method.
Three of the above-mentioned interfaces, more precisely 2D a-SnO2, 2D a-In2O3/In2Se3 and 2D-CrCl3 have been applied for the first time in gas sensing, achieving good performances in detecting reducing/oxidizing gases in dry/wet environments with good sensitivities, limits of detections (LOD) and long-term stabilities.
The 2D-SnSe2/TiO2 heterostructure showed promising results as a photoelectrocatalyst for the Oxygen Evolution Reaction (OER). Moreover, the electronic structure of the heterojunction has been schematized and a hypothesis on the mechanism given to explain its PEC-OER capabilities.
Some of the activities developed in this PhD work have been carried out in collaboration with other research groups, including the Department of Physical and Chemical Sciences of the University of L’Aquila, the Department of Chemistry of the University of Sassari and the Department of Industrial Engineering of the University of Padova. The gas sensor substrates design and manufacturing has been carried out in collaboration with Fondazione Bruno Kessler (FBK)
A new flea beetle genus from sub-Saharan Africa, and taxonomic remarks on the Blepharida genera group in the Afrotropical region (Chrysomelidae, Galerucinae, Alticini)
Get PDFCladocera fulvipennis Jacoby is transferred to Afrotropicaltica gen. nov., here described. The new genus belongs to the group of Afrotropical genera traditionally attributed to the Blepharida group: Blepharidina Bechyné, Calotheca Heyden, Diamphidia Gerstaecker, Polyclada Chevrolat, and Xanthophysca Fairmaire. A diagnostic key to these genera, and the list of species currently attributed to Diamphidia and Polyclada are provided based on type material and original species descriptions. Species and genera whose taxonomic position needs a revision were identified. Finally, the following synonymy is proposed: Cladocera fulvipennis Jacoby, 1895 = Blepharida favareli Achard, 1922, syn. nov
Hydrodynamic limit of an exclusion process with vorticity
Get PDFWe construct a non reversible exclusion process with Bernoulli product invariant measure and having, in the diffusive
hydrodynamic scaling, a non symmetric diffusion matrix, that can be explicitly computed. The antisymmetric part does not affect the
evolution of the density but it is relevant for the evolution of the current. Switching on a weak external field we obtain a symmetric
mobility matrix that is related just to the symmetric part of the diffusion matrix by an Einstein relation. We argue that this fact is typical
within a class of generalized gradient models. We consider for simplicity the model in dimension d = 2, but a similar behavior can be
also obtained in higher dimensions
A Biosocial Roadmap to Tackle the Burden of Hepatitis C Virus Infections That Ensures Health Equity for All
No full textLe “Machines à guérir” ossia i moderni spazi sanitari fra Ottocento e Novecento dal Vecchio al Nuovo continente
No full textMicroRNA-142-3p shuttling in extracellular vesicles marks regulatory T cell dysfunction in multiple sclerosis
No full textCD4+CD25hiFoxP3+ regulatory T cells (Treg cells) are key controllers of immune self-tolerance, and their suppressive function is impaired in people with relapsing-remitting multiple sclerosis (pwRR-MS). Because the mechanisms underlying this condition are still ill-defined, we investigated the role of Treg cell–derived extracellular vesicles (Treg-EVs) in Treg cell dysfunction observed in pwRR-MS. We found that Treg-EVs from healthy individuals inhibit CD4+ conventional T (Tconv) cells by shuttling miR-142-3p from the Treg cell to the Tconv cell. There, miR-142-3p down-regulated mRNAs necessary for Tconv cell growth and effector functions, such as the redox controller cystine carrier SLC7A11. However, Treg cells from pwRR-MS released EVs containing reduced amounts of miR-142-3p, resulting in impaired suppressive function. Furthermore, Treg-EV miR-142-3p inversely correlated with the disability score and gadolinium-enhancing lesions in pwRR-MS. Together, our results elucidate a molecular mechanism involving miR-142-3p shuttled by Treg-EVs in the control of immune self-tolerance and unveil its pathogenetic implications in human autoimmunity
Multicentre retrospective detection of nailfold videocapillaroscopy abnormalities in long covid patients
Get PDFBackground: SARS-CoV-2 induces acute non-specific endothelial/microvascular alterations that have been identified by nailfold videocapillaroscopy (NVC). Details on NVC abnormalities in long covid (LC) patients (pts) are unknown. Methods: LC pts without and with systemic sclerosis (non-SSc-LC and SSc-LC), recovered COVID-19 (RC) pts that did not develop LC and healthy matched control subjects (CNT) that underwent NVC examinations were evaluated in a multicentre national study from the Capillaroscopy and Microcirculation in Rheumatic Diseases Study Group of the Italian Society of Rheumatology. Retrospective collection was performed for demographic data, course of SARS-CoV-2 infection, comorbidities, concomitant drugs. NVC alterations were quantified by validated scores. Pre-COVID-19 and post-COVID-19 microvascular status was analysed by NVC. Results: 62 non-SSc-LC pts (49 female/13 male, 51±16 years old), 24 SSc-LC pts (21 female/3 male, 59±17 years old), 23 RC pts (18 female/5 male, 51±18 years old) and 84 CNT (68 female/16 male, 52±12 years old) were analysed. Non-SSc-LC pts showed significantly more dilated capillaries (p<0.01, p multivariate<0.01), microhaemorrhages (p=0.01, p multivariate<0.05), abnormal shapes (p<0.05, p multivariate<0.05) than CNT and of note, lower mean capillary number per linear millimetre (p<0.01, p multivariate<0.01) than both RC pts and CTN (p<0.01, p multivariate<0.05).Of highest interest, 16 non-SSc-LC pts showed statistically significantly more dilated capillaries (p<0.05) and microhaemorrhages (p<0.05) in NVC examinations after COVID-19, compared with pre-COVID-19 status.Similarly, SSc-LC pts (24) showed significantly lower capillary density (p=0.01) and more dilated capillaries (p<0.01) in NVC examinations after COVID-19, compared with pre-COVID-19 status. Conclusions: LC pts show more microvascular alterations at NVC as compared with RC patients and CNT, which may contribute to the pathogenesis of persistent organ/systems dysfunction
Strategie antifibrotiche in modelli in vitro e in vivo di malattia infiammatoria intestinale
No full textThis study investigates intestinal fibrosis in inflammatory bowel disease (IBD), particularly Crohn’s Disease (CD), where fibrosis leads to complications like stenosis and fistulae. While current treatments focus on inflammation, effective anti-fibrotic therapies remain limited. The study evaluates commonly used IBD drugs for their ability to counteract fibrosis-related processes, specifically fibroblast activation and epithelial-to-mesenchymal transition (EMT). Among the tested drugs, prednisone, methylprednisolone, budesonide, and adalimumab effectively reduced fibrosis markers, with methylprednisolone, budesonide, and adalimumab also mitigating EMT.
Additionally, the study examines losartan, an angiotensin II receptor blocker, for its anti-fibrotic potential. In vitro, losartan reversed angiotensin II-induced fibroblast activation and downregulated profibrotic genes. In vivo, using the SAMP mouse model of CD-like ileitis, losartan reduced inflammation and fibrosis, prevented fibrosis recurrence after steroid treatment, and downregulated AGTR1 expression. These findings suggest that losartan has direct anti-fibrotic effects independent of its anti-inflammatory properties, offering a potential new strategy for managing fibrosis in IBD