Chemical Design of Efficient Photoelectrodes by Heterogeneous Nucleation of Carbon Dots in Mesoporous Ordered Titania Films

The design of efficient and highly durable photoelectrodes requires innovative solutions that can be integrated into thin-film-based technologies. Mesoporous ordered titania, which is characterized by an organized porosity in the 2-10 nm range, represents an ideal matrix for such a purpose. One of the main challenges is the homogeneous and controlled incorporation of photoactive nanoparticles inside the matrix. Titania-carbon dots (C-dots) heterostructures represent promising candidates, but a method to homogeneously introduce C-dots in mesoporous films is still missing. In the present work, C-dots have been nucleated and grown within a mesoporous titania film through in situ solvothermal synthesis. The process promotes the crystallization of titania anatase at low temperatures and at the same time allows the formation of carbon dots without disruption of the porous ordered structure. The process allows building a high-performance nanocomposite as an electrode for oxygen evolution reactions. Photocurrent production under different illumination conditions was measured by linear sweep voltammetry and chronoamperometry. When exposed to a solar simulator, the nanocomposite electrodes yield an increase in photocurrent compared to bare TiO2 matrices. The better performance has been associated with the presence of C-dots acting as active light-harvesting sites and as charge donors to the photoactive centers of the titania film.Fil: Herrera, Facundo Carlos. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sireus, Veronica. Università Degli Studi Di Sassari; ItaliaFil: Rassu, Pietro. Università Degli Studi Di Sassari; ItaliaFil: Stagi, Luigi. Università Degli Studi Di Sassari; ItaliaFil: Reale, Marco. Università degli Studi di Palermo; ItaliaFil: Sciortino, Alice. Università degli Studi di Palermo; ItaliaFil: Messina, Fabrizio. Università degli Studi di Palermo; ItaliaFil: Soler Illia, Galo Juan de Avila Arturo. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Malfatti, Luca. Università Degli Studi Di Sassari; ItaliaFil: Innocenzi, Plinio. Università Degli Studi Di Sassari; Itali

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Human AP-endonuclease (Ape1) activity on telomeric G4 structures is modulated by acetylatable lysine residues in the N-terminal sequence

Loss of telomeres stability is a hallmark of cancer cells. Exposed telomeres are prone to aberrant end joining reactions leading to chromosomal fusions and translocations. Human telomeres contain repeated TTAGGG elements, in which the 3' exposed strand may adopt a G-quadruplex (G4) structure. The guanine-rich regions of telomeres are hotspots for oxidation forming 8-oxoguanine, a lesion that is handled by the base excision repair (BER) pathway. One key player of this pathway is Ape1, the main human endonuclease processing abasic sites. Recent evidences showed an important role for Ape1 in telomeric physiology, but the molecular details regulating Ape1 enzymatic activities on G4-telomeric sequences are lacking. Through a combination of in vitro assays, we demonstrate that Ape1 can bind and process different G4 structures and that this interaction involves specific acetylatable lysine residues (i.e. K-27/31/32/35) present in the unstructured N-terminal sequence of the protein. The cleavage of an abasic site located in a G4 structure by Ape1 depends on the DNA conformation or the position of the lesion and on electrostatic interactions between the protein and the nucleic acids. Moreover, Ape1 mutants mimicking the acetylated protein display increased cleavage activity for abasic sites. We found that nucleophosmin (NPM1), which binds the N-terminal sequence of Ape1, plays a role in modulating telomere length and Ape1 activity at abasic G4 structures. Thus, the Ape1 N-terminal sequence is an important relay site for regulating the enzyme's activity on G4-telomeric sequences, and specific acetylatable lysine residues constitute key regulatory sites of Ape1 enzymatic activity dynamics at telomeres

18F-sodium fluoride PET-CT for the assessment of brain metastasis from lung Adenocarcinoma

11norestrictedrestrictedGori, Stefania; Inno, Alessandro*; Lunardi, Gianluigi; Gorgoni, Giancarlo; Malfatti, Veronica; Severi, Fabrizia; Alongi, Filippo; Carbognin, Giovanni; Romano, Luigi; Pasetto, Stefano; Salgarello, MatteoGori, Stefania; Inno, Alessandro; Lunardi, Gianluigi; Gorgoni, Giancarlo; Malfatti, Veronica; Severi, Fabrizia; Alongi, Filippo; Carbognin, Giovanni; Romano, Luigi; Pasetto, Stefano; Salgarello, Matte

Role of Combined Ga-68-DOTATOC and F-18-FDG Positron Emission Tomography/Computed Tomography in the Diagnostic Workup of Pancreas Neuroendocrine Tumors Implications for Managing Surgical Decisions

Objectives: Ga-68-DOTATOC (Ga) positron emission tomography (PET)/computed tomography (CT) is recommended in the workup of pancreas neuroendocrine tumors (PanNETs); evidence suggests that F-18-FDG (F) PET/CT can also provide prognostic information. Aims of this study were to assess the role of combined Ga-and F-PET/CT in the evaluation of grade (G) 1-2 PanNETs and to test the correlation between F-PET/CT positivity and tumor grade.Methods: Preoperative Ga-and F-PET/CT of 35 patients with surgically resected G1-2 PanNETs were evaluated. For grading, the 2010 World Health Organization Classification was used; an ancillary analysis with Ki67 cutoffs at 5% to 20% was conducted. Correlation between F-PET/ CT positivity (SUVmax > 3.5) and grade was assessed.Results: Of 35 PanNETs, 28.6% and 71.4% were G1 and G2 as per World Health Organization. Ga-PET/CT showed high sensitivity (94.3%) in detecting G1-2 PanNETs. F-PET/CT was positive in 20% and 76% G1 and G2 tumors (P = 0.002). F-PET/CT identified G2 PanNETs with high positive predictive value (PPV, 90.5%). F-PET/CT correlated with tumor grade also in the ancillary analysis (P = 0.009).Conclusions: The high sensitivity of Ga-PET/CT in NET detection is known. The high PPV of F-PET/CT in the identification of G2 forms suggests its potential role in PanNETs prognostication and risk stratification