University of Perugia

About: University of Perugia is a education organization based out in Perugia, Umbria, Italy. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 13365 authors who have published 39516 publications receiving 1265601 citations. The organization is also known as: Universitá degli Studi di Perugia & Universita degli Studi di Perugia.

BRAF Mutations in Papillary Thyroid Carcinomas Inhibit Genes Involved in Iodine Metabolism

Abstract: Context: BRAF mutations are common in papillary thyroid carcinomas (PTCs). By affecting the expression of genes critically related to the development and differentiation of thyroid cancer, they may influence the prognosis of these tumors. Objective: Our objective was to characterize the expression of thyroid-specific genes associated with BRAF mutation in PTCs. Design/Setting and Patients: We examined the expression of key markers of thyrocyte differentiation in 56 PTCs with BRAF mutations (BRAF-mut) and 37 with wild-type BRAF (BRAF-wt). Eight samples of normal thyroid tissue were analyzed as controls. Quantitative PCR was used to measure mRNA levels for the sodium/iodide symporter (NIS), apical iodide transporter (AIT-B), thyroglobulin (Tg), thyroperoxidase (TPO), TSH receptor (TSH-R), the transcription factor PAX8, and glucose transporter type 1 (Glut1). NIS protein expression and localization was also analyzed by immunohistochemistry. Results: mRNA levels for all thyroid-specific genes were reduced in ...

The organic-rich surface of comet 67P/Churyumov-Gerasimenko as seen by VIRTIS/Rosetta

Abstract: The VIRTIS (Visible, Infrared and Thermal Imaging Spectrometer) instrument on board the Rosetta spacecraft has provided evidence of carbon-bearing compounds on the nucleus of the comet 67P/Churyumov-Gerasimenko The very low reflectance of the nucleus (normal albedo of 0060 ± 0003 at 055 micrometers), the spectral slopes in visible and infrared ranges (5 to 25 and 15 to 5% kA−1), and the broad absorption feature in the 29-to-36–micrometer range present across the entire illuminated surface are compatible with opaque minerals associated with nonvolatile organic macromolecular materials: a complex mixture of various types of carbon-hydrogen and/or oxygen-hydrogen chemical groups, with little contribution of nitrogen-hydrogen groups In active areas, the changes in spectral slope and absorption feature width may suggest small amounts of water-ice However, no ice-rich patches are observed, indicating a generally dehydrated nature for the surface currently illuminated by the Sun

Association Between Vitamin D Status and Physical Performance: The InCHIANTI Study

Abstract: With a growing older population, there is an increasing need to identify potentially modifiable risk factors for the onset of disability. In the past two decades, it has become evident that the role of vitamin D extends beyond calcium homeostasis and includes modulation of skeletal and cardiac muscle function, immune cell function, and anticancer activity (1). Within the muscle cell, vitamin D plays an important role in the regulation of calcium transport and protein synthesis (2,3). In older adults, low serum vitamin D (serum 25OHD) levels have been associated with muscle weakness, poor physical performance, balance problems, and falls, although findings from different studies are somewhat inconsistent (4–11). Thus, vitamin D deficiency may not only affect the onset of chronic conditions, which are frequent causes of disability, but may also directly affect functional status through vitamin D’s role in muscle function. Consensus to define a cut-point for vitamin D insufficiency based on serum 25OHD levels is lacking. Various cut-points have been proposed based on population-based reference limits or biological indices, such as parathyroid hormone (PTH), calcium absorption, or bone mineral density, with cut-points for serum 25OHD insufficiency ranging from 50 to 80 nmol/L (12–14). Regardless, low levels of serum 25OHD are common in older populations with wide variability in prevalence depending on geographic location, season, and the cut-points used to define insufficiency and/or deficiency (15–19). Older adults are at risk for low serum 25OHD because of reduced exposure to ultraviolet B (UVB) radiation and reduced efficiency of previtamin D synthesis in the skin (20). Dietary intake of vitamin D is also often inadequate, as there are few natural food sources of vitamin D (16). Low serum 25OHD may also indirectly affect muscle function via hyperparathyroidism secondary to vitamin D deficiency (17). Primary hyperparathyroidism is characterized by muscle weakness that is improved by treatment (21,22). It has been demonstrated that administration of PTH negatively affects skeletal muscle function in animal models (2,3,17). PTH has also been shown to induce the production of serum interleukin-6 (IL-6) (23). Observational studies have shown that elevated IL-6 levels are associated with lower muscle strength and poor physical performance (24,25). However, few studies have examined the joint effect of vitamin D and PTH on physical performance (9,10). The objective of this study was to examine the associations between vitamin D status and physical performance using data from the InCHIANTI study. Comparisons between different serum 25OHD cut-points and physical performance were examined. Additionally, the association between PTH and physical performance and the role of PTH as a potential mediator in the association between serum 25OHD and physical performance was examined.

Adjuvant Erlotinib Versus Placebo in Patients With Stage IB-IIIA Non–Small-Cell Lung Cancer (RADIANT): A Randomized, Double-Blind, Phase III Trial

Abstract: Purpose Epidermal growth factor receptor (EGFR) –tyrosine kinase inhibitors have proven efficacy in advanced non–small-cell lung cancer (NSCLC). We hypothesized that erlotinib would be efficacious in the adjuvant setting. Patients and Methods An international randomized, double-blind, placebo-controlled study was conducted in patients with completely resected IB to IIIA NSCLC whose tumors expressed EGFR protein by immunohistochemistry or EGFR amplification by fluorescence in situ hybridization. Patients were assigned 2:1 to erlotinib 150 mg once per day or placebo for 2 years. Stratification factors were stage, histology, previous adjuvant chemotherapy, smoking status, EGFR amplification status, and country. The primary end point was disease-free survival (DFS); key secondary end points were overall survival (OS) and DFS and OS in patients whose tumors had EGFR-activating mutations (EGFRm-positive). Results A total of 973 patients were randomly assigned (November 26, 2007, to July 7, 2010). There was no s...