151 research outputs found

    Nanomanufacturing of titania interfaces with controlled structural and functional properties by supersonic cluster beam deposition

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    Great emphasis is placed on the development of integrated approaches for the synthesis and the characterization of ad hoc nanostructured platforms, to be used as templates with controlled morphology and chemical properties for the investigation of specific phenomena of great relevance for technological applications in interdisciplinary fields such as biotechnology, medicine and advanced materials. Here we discuss the crucial role and the advantages of thin film deposition strategies based on cluster-assembling from supersonic cluster beams. We select cluster-assembled nanostructured titania (ns-TiO2) as a case study to demonstrate that accurate control over morphological parameters can be routinely achieved, and consequently over several relevant interfacial properties and phenomena, like surface charging in a liquid electrolyte, and proteins and nanoparticles adsorption

    Realtà e Prospettive nel management sanitario: uno studio all’ombra dei leader

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    2016 - 2017The appropriate and sustainable management of health care organizations is a timely and relevant topic. It achieves a growing popularity in light of the deep processes of institutional and structural changes which are affecting the health care context in the last few years. Therefore, it is crucial to push forward our knowledge about the management tools and approaches which allow to enhance the effectiveness of health care organizations, whose dimension – as required by recent legislative reforms – is continuously growing. Clinical leadership – that is to say the leadership which is enacted within health care organizations by providers of health services – is a momentous topic in the field of health care management and organization. This thesis aims at illuminating a “dark side” of clinical leadership: the role of gender differences in triggering diverging approaches to clinical leadership. For this purpose, a qualitative analysis was performed, which involved a medium-sized health care organization operating in Italy. A mixed approach was used, which joined a high level, “managerial” interpretation with a more depth, psychological interpretation of clinical leaders’ behaviors and approaches. Attention has been paid to the organizational implications of the specific leadership styles implemented by two key informants, who were identified as the primary sources of information for the purpose of this study. In line with the main aim of this study, a man and a woman were involved in this research. The psychological determinants of leaders’ approaches and behaviors were carefully investigated, in an attempt to point out gender-based differences. The two leaders belonged to the same health care organizations and had the same organizational role; they supervised two organizational units which were comparable in terms of health competencies and clinical practices. This thesis is organized as follows. Firstly, the “leadership” concept is presented, sticking to the prevailing theoretical frameworks which assist in underpinning this construct. Gender-based theories were elicited, in order to pave the way for the study development. Then, the strategic leadership mind-set is presented, focusing on the psychological and cognitive dimensions inspiring leaders’ practices. The second chapter proposes a literature review of the “clinical leadership” concept, identifying the management implications that it is able to generate on the proper functioning of health care organizations; once again, a particular emphasis is put on gender differences in the exercise of clinical leadership. The third chapter shows the research strategy and design. A single case study approach was taken. It was implemented through the “shadowing” method. The two leaders who were engaged in this analysis were carefully observed by the author during their every-day working activity; moreover, multiple semi-structured interviews were administered, in order to deepen the research findings. The result of this study point out that the styles of clinical leadership may be either transformational or transactional. Even though the approach taken does not allow generalization, the exercise of leadership is deeply affected by gender-based biases. On the one hand, female leaders are more inclined to embrace a transformational clinical leadership style; on the other hand, male leaders are more likely to use a transactional style. It is worth noting that differences in clinical leadership have relevant implications on the management of individual units within health care organizations; also, they affect the relationship between leaders, followers and supervisors. Lastly, yet importantly, such differences influence the patient-provider relationship, with drawbacks on the providers’ ability to fully detect and meet the needs of their patients. [edited by Author]XVI n.s. (XXX ciclo

    The Role of MicroRNAs in Mitochondria-Mediated Eye Diseases

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    The retina is among the most metabolically active tissues with high-energy demands. The peculiar distribution of mitochondria in cells of retinal layers is necessary to assure the appropriate energy supply for the transmission of the light signal. Photoreceptor cells (PRs), retinal pigment epithelium (RPE), and retinal ganglion cells (RGCs) present a great concentration of mitochondria, which makes them particularly sensitive to mitochondrial dysfunction. To date, visual loss has been extensively correlated to defective mitochondrial functions. Many mitochondrial diseases (MDs) show indeed neuro-ophthalmic manifestations, including retinal and optic nerve phenotypes. Moreover, abnormal mitochondrial functions are frequently found in the most common retinal pathologies, i.e., glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR), that share clinical similarities with the hereditary primary MDs. MicroRNAs (miRNAs) are established as key regulators of several developmental, physiological, and pathological processes. Dysregulated miRNA expression profiles in retinal degeneration models and in patients underline the potentiality of miRNA modulation as a possible gene/mutation-independent strategy in retinal diseases and highlight their promising role as disease predictive or prognostic biomarkers. In this review, we will summarize the current knowledge about the participation of miRNAs in both rare and common mitochondria-mediated eye diseases. Definitely, given the involvement of miRNAs in retina pathologies and therapy as well as their use as molecular biomarkers, they represent a determining target for clinical applications

    Synthetic long non-coding RNAs [SINEUPs] rescue defective gene expression in vivo

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    Non-coding RNAs provide additional regulatory layers to gene expression as well as the potential to being exploited as therapeutic tools. Non-coding RNA-based therapeutic approaches have been attempted in dominant diseases, however their use for treatment of genetic diseases caused by insufficient gene dosage is currently more challenging. SINEUPs are long antisense non-coding RNAs that up-regulate translation in mammalian cells in a gene-specific manner, although, so far evidence of SINEUP efficacy has only been demonstrated in in vitro systems. We now show that synthetic SINEUPs effectively and specifically increase protein levels of a gene of interest in vivo. We demonstrated that SINEUPs rescue haploinsufficient gene dosage in a medakafish model of a human disorder leading to amelioration of the disease phenotype. Our results demonstrate that SINEUPs act through mechanisms conserved among vertebrates and that SINEUP technology can be successfully applied in vivo as a new research and therapeutic tool for gene-specific up-regulation of endogenous functional proteins

    Biomimetic poly(amidoamine) hydrogels as synthetic materials for cell culture

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    <p>Abstract</p> <p>Background</p> <p>Poly(amidoamine)s (PAAs) are synthetic polymers endowed with many biologically interesting properties, being highly biocompatible, non toxic and biodegradable. Hydrogels based on PAAs can be easily modified during the synthesis by the introduction of functional co-monomers. Aim of this work is the development and testing of novel amphoteric nanosized poly(amidoamine) hydrogel film incorporating 4-aminobutylguanidine (agmatine) moieties to create RGD-mimicking repeating units for promoting cell adhesion.</p> <p>Results</p> <p>A systematic comparative study of the response of an epithelial cell line was performed on hydrogels with agmatine and on non-functionalized amphoteric poly(amidoamine) hydrogels and tissue culture plastic substrates. The cell adhesion on the agmatine containing substrates was comparable to that on plastic substrates and significantly enhanced with respect to the non-functionalized controls. Interestingly, spreading and proliferation on the functionalized supports are slower than on plastic exhibiting the possibility of an easier control of the cell growth kinetics. In order to favor the handling of the samples, a procedure for the production of bi-layered constructs was also developed by means the deposition via spin coating of a thin layer of hydrogel on a pre-treated cover slip.</p> <p>Conclusion</p> <p>The obtained results reveal that PAAs hydrogels can be profitably functionalized and, in general, undergo physical and chemical modifications to meet specific requirements. In particular the incorporation of agmatine warrants good potential in the field of cell culturing and the development of supported functionalized hydrogels on cover glass are very promising substrates for applications in cell screening devices.</p

    Linearized texture of three-dimensional extracellular matrix is mandatory for bladder cancer cell invasion

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    In the fields of biomaterials and tissue engineering simulating the native microenvironment is of utmost importance. As a major component of the microenvironment, the extracellular matrix (ECM) contributes to tissue homeostasis, whereas modifications of native features are associated with pathological conditions. Furthermore, three-dimensional (3D) geometry is an important feature of synthetic scaffolds favoring cell stemness, maintenance and differentiation. We analyzed the 3D structure, geometrical measurements and anisotropy of the ECM isolated from (i) human bladder mucosa (basal lamina and lamina propria) and muscularis propria; and, (ii) bladder carcinoma (BC). Next, binding and invasion of bladder metastatic cell line was observed on synthetic scaffold recapitulating anisotropy of tumoral ECM, but not on scaffold with disorganized texture typical of non-neoplastic lamina propria. This study provided information regarding the ultrastructure and geometry of healthy human bladder and BC ECMs. Likewise, using synthetic scaffolds we identified linearization of the texture as a mandatory feature for BC cell invasion. Integrating microstructure and geometry with biochemical and mechanical factors could support the development of an innovative synthetic bladder substitute or a tumoral scaffold predictive of chemotherapy outcomes

    Microglia reactivity entails microtubule remodeling from acentrosomal to centrosomal arrays

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    Microglia reactivity entails a large-scale remodeling of cellular geometry, but the behavior of the microtubule cytoskeleton during these changes remains unexplored. Here we show that activated microglia provide an example of microtubule reorganization from a non-centrosomal array of parallel and stable microtubules to a radial array of more dynamic microtubules. While in the homeostatic state, microglia nucleate microtubules at Golgi outposts, and activating signaling induces recruitment of nucleating material nearby the centrosome, a process inhibited by microtubule stabilization. Our results demonstrate that a hallmark of microglia reactivity is a striking remodeling of the microtubule cytoskeleton and suggest that while pericentrosomal microtubule nucleation may serve as a distinct marker of microglia activation, inhibition of microtubule dynamics may provide a different strategy to reduce microglia reactivity in inflammatory disease

    miR-181a/b downregulation exerts a protective action on mitochondrial disease models.

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    Mitochondrial diseases (MDs) are a heterogeneous group of devastating and often fatal disorders due to defective oxidative phosphorylation. Despite the recent advances in mitochondrial medicine, effective therapies are still not available for these conditions. Here, we demonstrate that the microRNAs miR-181a and miR-181b (miR-181a/b) regulate key genes involved in mitochondrial biogenesis and function and that downregulation of these miRNAs enhances mitochondrial turnover in the retina through the coordinated activation of mitochondrial biogenesis and mitophagy. We thus tested the effect of miR-181a/b inactivation in different animal models of MDs, such as microphthalmia with linear skin lesions and Leber\u27s hereditary optic neuropathy. We found that miR-181a/b downregulation strongly protects retinal neurons from cell death and significantly ameliorates the disease phenotype in all tested models. Altogether, our results demonstrate that miR-181a/b regulate mitochondrial homeostasis and that these miRNAs may be effective gene-independent therapeutic targets for MDs characterized by neuronal degeneration

    SINEUP non-coding RNAs rescue defective frataxin expression and activity in a cellular model of Friedreich's Ataxia

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    Friedreich's ataxia (FRDA) is an untreatable disorder with neuro- and cardio-degenerative progression. This monogenic disease is caused by the hyper-expansion of naturally occurring GAA repeats in the first intron of the FXN gene, encoding for frataxin, a protein implicated in the biogenesis of iron-sulfur clusters. As the genetic defect interferes with FXN transcription, FRDA patients express a normal frataxin protein but at insufficient levels. Thus, current therapeutic strategies are mostly aimed to restore physiological FXN expression. We have previously described SINEUPs, natural and synthetic antisense long non-coding RNAs, which promote translation of partially overlapping mRNAs through the activity of an embedded SINEB2 domain. Here, by in vitro screening, we have identified a number of SINEUPs targeting human FXN mRNA and capable to up-regulate frataxin protein to physiological amounts acting at the post-transcriptional level. Furthermore, FXN-specific SINEUPs promote the recovery of disease-associated mitochondrial aconitase defects in FRDA-derived cells. In summary, we provide evidence that SINEUPs may be the first gene-specific therapeutic approach to activate FXN translation in FRDA and, more broadly, a novel scalable platform to develop new RNA-based therapies for haploinsufficient diseases
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