Observation of the Early Structural Changes Leading to the Formation of Protein Superstructures.

Formation of superstructures in protein aggregation processes has been indicated as a general pathway for several proteins, possibly playing a role in human pathologies. There is a severe lack of knowledge on the origin of such species in terms of both mechanisms of formation and structural features. We use equine lysozyme as a model protein, and by combining spectroscopic techniques and microscopy with X-ray fiber diffraction and ab initio modeling of Small Angle X-ray Scattering data, we isolate the partially unfolded state from which one of these superstructures (i.e., particulate) originates. We reveal the low-resolution structure of the unfolded state and its mechanism of formation, highlighting the physicochemical features and the possible pathway of formation of the particulate structure. Our findings provide a novel detailed knowledge of such a general and alternative aggregation pathway for proteins, this being crucial for a basic and broader understanding of the aggregation phenomena.This is the author's accepted manuscript and will be under embargo until the 3rd of September 2015. The final version is published by ACS in The Journal of Physical Chemistry Letters here: http://pubs.acs.org/doi/abs/10.1021/jz501614e

Novel Combination of Sorafenib and Celecoxib Provides Synergistic Anti-Proliferative and Pro-Apoptotic Effects in Human Liver Cancer Cells

Molecular targeted therapy has shown promise as a treatment for advanced hepatocellular carcinoma (HCC). Sorafenib, a multikinase inhibitor, recently received FDA approval for the treatment of advanced HCC. However, although sorafenib is well tolerated, concern for its safety has been expressed. Celecoxib (Celebrex®) is a selective cyclooxygenase-2 (COX-2) inhibitor which exhibits antitumor effects in human HCC cells. The present study examined the interaction between celecoxib and sorafenib in two human liver tumor cell lines HepG2 and Huh7. Our data showed that each inhibitor alone reduced cell growth and the combination of celecoxib with sorafenib synergistically inhibited cell growth and increased apoptosis. To better understand the molecular mechanisms underlying the synergistic antitumor activity of the combination, we investigated the expression profile of the combination-treated liver cancer cell lines using microarray analysis. Combination treatment significantly altered expression levels of 1,986 and 2,483 transcripts in HepG2 and Huh7 cells, respectively. Genes functionally involved in cell death, signal transduction and regulation of transcription were predominantly up-regulated, while genes implicated in metabolism, cell-cycle control and DNA replication and repair were mainly down-regulated upon treatment. However, combination-treated HCC cell lines displayed specificity in the expression and activity of crucial factors involved in hepatocarcinogenesis. The altered expression of some of these genes was confirmed by semi-quantitative and quantitative RT-PCR and by Western blotting. Many novel genes emerged from our transcriptomic analyses, and further functional analyses may determine whether these genes can serve as potential molecular targets for more effective anti-HCC strategies

Assessment of the drill-and-blast related overbreak in the BBT system

Drill-and-blast is the common conventional tunnelling method in hard rock conditions. This paper analyses the characteristics of the blasting-induced overbreak in some of the tunnels of the Brenner Base Tunnel (BBT) system, in order to evaluate its correlation with the main geometrical and technical parameters of the excavation as well as the geomechanical properties of the rock mass. In particular, starting from Terrestrial Laser Scanning measurements and direct overbreak observations, it was possible to distinguish so-called geological overbreaks (due to the pre-existing discontinuities in the rock mass) from technical ones (related to the appropriate performance of the excavation technique) on the basis of the after-blasting presence of half-casts. Data were used to develop a multiparametric regression model based on the RMR index and length of the blast holes, recognized respectively as the main factors influencing the two mentioned overbreak types. Model parameters were initially calibrated over a portion of the Mules access tunnel excavated in micaschists and subsequently validated against experimental evidence collected along tunnels of different geometries driven through granite and paragneiss rock-masses. The overbreak model proved to successfully predict the correlation between overbreaks (especially that fraction related to the geomechanical characteristics of the rock-mass), RMR and length of the blast holes. As such, its preliminary application can provide a reliable first-assessment of extra costs and time during the design stage

Factors influencing overbreak volumes in drill-and-blast tunnel excavation. A statistical analysis applied to the case study of the Brenner Base Tunnel - BBT

This paper deals with the analysis of overbreak in tunnels excavated with the drill-and-blast method. The overbreak phenomenon has many negative impacts on tunnelling organisation and economy and its precise assessment plays a fundamental role in the process of construction optimisation. The study proposes an operative methodology to estimate overbreak volumes and to distinguish so-called technical overbreak, mainly related to drill-and-blast design and execution, from geological overbreak, typically influenced by rock-mass characteristics. The approach was developed and implemented during the excavation of the Brenner Base Tunnel (BBT) and was based on the interpretation of tunnel laser scanning surveys and high-resolution images of the excavated surfaces. The analysis of more than 1,800 m of excavation from three different tunnels of the BBT system allowed to identify the main factors influencing the technical and the geological overbreak. An empirical model for overbreak prediction, based on the Rock Mass Rating index and the length of blast holes, is subsequently presented and validated in the last part of the paper

Performance of different diameter Double Shield TBMs: experiences from the excavation of exploratory tunnel and main tubes of the Italian lot Mules 2-3 – Brenner Base Tunnel

The Brenner Base Tunnel is a 64 km long underground railway connection under construction between Italy and Austria. The project mainly consists of two main one-track tunnels and a central exploratory tunnel 12 m below them. Considering that the three tunnels intersected the same rock masses and fault zones, the paper analyses the scale factor displayed by selected machine parameters in relation to the tunnel diameter, TBM characteristics and rock mass conditions. Final considerations about the performance of the three TBMs, also in the context of comparable case-histories, are addressed

Brevetti

Per il lavoro di ricerca,di cui il libro "Glassblock and Architecture. Evoluzione del vetromattone e recenti applicazioni" rappresenta una sintesi preliminare,sono stati analizzati e riportati in elenco numerosi brevetti sul vetromattone ed i sistemi di posa in opera ad esso correlati oltre che alcuni specifici accorgimenti atti a migliorare le caratteristiche del vetro e degli “accessori” utili all’istallazione dei vetromattoni stessi.Di ciascun brevetto si riportano il nome dell'autore, l’azienda per la quale il brevetto stesso è stato richiesto e pubblicato (laddove esistente), la data di presentazione della domanda di brevettazione e la relativa data di concessione

Non-occlusive mesenteric ischaemia (NOMI) with and without reperfusion: CT features useful for diagnosis and their prognostic value

Purpose: NOMI is a dynamic condition. Its appearance at imaging may be different depending on the time in which CT examination is performed and on the presence of reperfusion event. The aim of our work has been to assess the efficacy of MDCT for the diagnosis of NOMI, with and without reperfusion event. Methods and Materials: Clinical and imaging data from 20 patients (16 males, 4 females) with a dismissal summary of NOMI were retrospectively reviewed. All patients had at least 1 abdominal MDCT examination (n=28) followed by surgery (n=8), autopsy (n=2), angiography (n=1) or endoscopy (n=9). The CT scans were evaluated for evidence of vessels, mesentery, bowel and cavity features. The mean diameter of the SMA of NOMI cases were compared with that of 30 controlled cases. Results: The average SMA diameter of NOMI cases were statistically smaller than that of controls (K-S test: D=0.75, Prob=3.7E‑08). A correlation between the reperfusion event and mesenteric fat stranding (p=0.026), bowel wall thickening (p=3.2E‑05) and high attenuation of the bowel wall on unenhanced CT images (p=2.8E‑04) was demonstrated by Fisher’s exact tests. Normal mesenteric vessels plus wall thickening was significantly correlated with lower mortality (p= 0.034). Conclusion: The evaluation of mesentery, bowel and peritoneal CT features, in addition to the vessel findings will supply additional information to recognise NOMI and in discriminating the presence of a reperfusion event

Electrostatics controls the formation of amyloid superstructures in protein aggregation.

The possibility for proteins to aggregate in different superstructures, i.e. large-scale polymorphism, has been widely observed, but an understanding of the physicochemical mechanisms behind it is still out of reach. Here we present a theoretical model for the description of a generic aggregate formed from an ensemble of charged proteins. The model predicts the formation of multifractal structures with the geometry of the growth determined by the electrostatic interactions between single proteins. The model predictions are successfully verified in comparison with experimental curves for aggregate growth allowing us to reveal the mechanism of formation of such complex structures. The model is general and is able to predict aggregate morphologies occurring both in vivo and in vitro. Our findings provide a framework where the physical interactions between single proteins, the aggregate morphology, and the growth kinetics are connected into a single model in agreement with the experimental data.Funding from the Engineering and Physical Sciences Research Council (EP/H004939/1), the Swiss National Science Foundation (Grants Nr. PBEZP2-131153 and Nr. 200020-126487/1) is gratefully acknowledged. A.Z. acknowledges support from the Ernest Oppenheimer Fellowship at Cambridge.This is the accepted version of the original publication in Physical Review Letters, which is published online here: http://prl.aps.org/abstract/PRL/v111/i10/e108105. © 2013 American Physical Societ