Studio di un algoritmo lineare di ricostruzione analogica della posizione per il rivelatore a pixel di ATLAS

A detailed study of spatial resolution of Atlas pixel sensors prototypes was performed. Charge interpolation was used and allowed for a significant improvement with respect to digital resolution. A simplified algorithm for charge interpolation was developed. Its application to both unirradiated and irradiated sensors is presented and discussed

Mechanotransduction in human and mouse beta cell lines: reliable models to characterize novel signaling pathways controlling beta cell fate

Background and aims: Attempts to influence \u3b2-cell differentiation by engineering substrates that mimic appropriate extracellular matrix (ECM) topographies are hampered by the fact that profound details of mechanosensing/transduction complexity remain elusive. We recently demonstrated that human islets of Langerhans sense the ECM nanotopography and activate a mechanotransductive pathway, which is essential for preserving long-term \u3b2-cell differentiation and function in vitro. However, human islets of Langerhans are extremely heterogeneous and their availability for research purpose is limited. Therefore, aim of the proposed research was to investigate whether mouse and human \u3b2-cell lines might sense changes innthe ECM topography and might be used as a simplified model to dissect the molecular pathways involved in mechanotransduction. Materials and methods: We used supersonic cluster beam deposition to fabricate nanostructured substrates characterized by a quantitatively controllable ECM-like nanoroughness. Mouse \u3b2TC3 and human 1.1B4 cells were seeded on these substrates and after five days in culture, the activation of the mechanotransductive pathway was verified by means of morphological (super-resolution fluorescence microscopy), functional and proteomic techniques. Results: Quantitative immunofluorescence studies demonstrated that the cell-nanotopography interaction affects the focal adhesion structures (smaller vinculin clusters), the organization of the actin cytoskeleton (shorter actin fiber) and the nuclear architecture. Functional studies revealed that nanostructured surfaces improve the \u3b2-cell mitochondrial activity and increase the glucose-stimulated Ca2+currents and insulin release. Label-free shotgun proteomics broadly confirmed the morphological and functional studies and showed the upregulation of a number of mechanosensors and transcription factors involved in \u3b2-cell differentiation in cells grown on nanostructured substrates compared to those grown on flat standard control surfaces. Conclusion: Our data reveal that mouse and human \u3b2-cell lines sense changes in extracellular mechanical forces and activate a mechanotransductive pathway. The findings from this study will be useful to clarify the link between mechanotransduction and cell fate and to successfully engineer scaffolds in order to have functional beta cells

Proteomic Analysis Reveals a Mitochondrial Remodeling of βTC3 Cells in Response to Nanotopography

Recently, using cluster-assembled zirconia substrates with tailored roughness produced by supersonic cluster beam deposition, we demonstrated that \u3b2 cells can sense nanoscale features of the substrate and can translate these stimuli into a mechanotransductive pathway capable of preserveing \u3b2-cell differentiation and function in vitro in long-term cultures of human islets. Using the same proteomic approach, we now focused on the mitochondrial fraction of \u3b2TC3 cells grown on the same zirconia substrates and characterized the morphological and proteomic modifications induced by the nanostructure. The results suggest that, in \u3b2TC3 cells, mitochondria are perturbed by the nanotopography and activate a program involving metabolism modification and modulation of their interplay with other organelles. Data were confirmed in INS1E, a different \u3b2-cell model. The change induced by the nanostructure can be pro-survival and prime mitochondria for a metabolic switch to match the new cell needs

Società Italiana delle Letterate

For this issue, the Società Italiana delle Letterate presents two contributions: an article by Francesca Maffioli intersecting Amalia Rosselli’s writing with the idea of écriture féminine theorized by Hélène Cixous; and a new review from the future by Sara Positano, who offers an overview of the proceedings from the conference "The space of writing. Compared to female literature" SIL organized in 2002. Both texts represent instances of the critical thought, past and present, that the association keeps producing on women's literature, in a global perspective. which emerges as topical as ever

Acute environmental temperature variation affects brain protein expression, anxiety and explorative behaviour in adult zebrafish

This study investigated the effect of 4-d acute thermal treatments at 18 \ub0C, 26 \ub0C (control) and 34 \ub0C on the nervous system of adult zebrafish (Danio rerio) using a multidisciplinary approach based on behavioural tests and brain proteomic analysis. The behavioural variations induced by thermal treatment were investigated using five different tests, the novel tank diving, light and dark preference, social preference, mirror biting, and Y-Maze tests, which are standard paradigms specifically tailored for zebrafish to assess their anxiety-like behaviour, boldness, social preference, aggressiveness, and explorative behaviour, respectively. Proteomic data revealed that several proteins involved in energy metabolism, messenger RNA translation, protein synthesis, folding and degradation, cytoskeleton organisation and synaptic vesiculation are regulated differently at extreme temperatures. The results showed that anxiety-like behaviours increase in zebrafish at 18 \ub0C compared to those at 26 \ub0C or 34 \ub0C, whereas anxiety-related protein signalling pathways are downregulated. Moreover, treatments at both 18 \ub0C and 34 \ub0C affect the exploratory behaviour that appears not to be modulated by past experiences, suggesting the impairment of fish cognitive abilities. This study is the continuation of our previous work on the effect of 21-d chronic treatment at the same constant temperature level and will enable the comparison of acute and chronic treatment effects on the nervous system function in adult zebrafish

Proteomic profile of maternal-aged blastocoel fluid suggests a novel role for ubiquitin system in blastocyst quality

Purpose: The etiology of maternal aging, a common cause of female factor infertility and a rate-limiting step in vitro fertilization (IVF) success, remains still unclear. Proteomic changes responsible for the impaired successful pregnancy outcome after IVF with aged blastocysts have not been yet evaluated. The objective of this prospective study was to employ proteomic techniques and bioinformatic tools to enlight differences at the protein level in blastocoel fluid of aged and younger woman. Methods: Protein composition of human blastocoel fluid isolated by micromanipulation from 46 blastocysts of women aged <37 years (group A) and 29 of women aged 6537 years (group B) have been identified by a shotgun proteomic approach based on high-resolution nano-liquid chromatography electrospray-ionization-tandem mass spectrometry (nLC-ESI-MS/MS) using label free for the relative quantification of their expression levels. Results: The proteomic analysis leads to the identification and quantification of 148 proteins; 132 and 116 proteins were identified in groups A and B, respectively. Interestingly, the identified proteins are mainly involved in processes aimed at fine tuning embryo implantation and development. Among the 100 proteins commonly expressed in both groups, 17 proteins are upregulated and 44 downregulated in group B compared to group A. Overall, the analysis identified 33 proteins, which were increased or present only in B while 76 were decreased in B or present only in A. Conclusions: Data revealed that maternal aging mainly affects blastocyst survival and implantation through unbalancing the equilibrium of the ubiquitin system known to play a crucial role in fine-tuning several aspects required to ensure successful pregnancy outcome