Proton CT on biological phantoms for x-ray CT calibration in proton treatment planning.

To present and characterize a novel method for x-ray computed tomography (xCT) calibration in proton treatment planning, based on proton CT (pCT) measurements on biological phantoms.A pCT apparatus was used to perform direct measurements of 3D stopping power relative to water (SPR) maps on stabilized, biological phantoms. Two single-energy xCT calibration curves-i.

Quantitative assessment of transmural fibrosis profile in the human atrium: evidence for a three-dimensional arrhythmic substrate by slice-to-slice histology.

Aims: Intramural fibrosis represents a crucial factor in the formation of a three-dimensional (3D) substrate for atrial fibrillation (AF). However, the transmural distribution of fibrosis and its relationship with atrial overload remain largely unknown. The aim of this study is to quantify the transmural profile of atrial fibrosis in patients with different degrees of atrial dilatation and arrhythmic profiles by a high-resolution 3D histology method.

Upregulation of miR-133b and miR-328 in Patients With Atrial Dilatation: Implications for Stretch-Induced Atrial Fibrillation.

Atrial stretch and dilatation are common features of many clinical conditions predisposing to atrial fibrillation (AF). MicroRNAs (miRs) are emerging as potential molecular determinants of AF, but their relationship with atrial dilatation (AD) is poorly understood. The present study was designed to assess the specific miR expression profiles associated with AD in human atrial tissue.

Selection of reference genes is critical for miRNA expression analysis in human cardiac tissue. A focus on atrial fibrillation.

MicroRNAs (miRNAs) are emerging as key regulators of complex biological processes in several cardiovascular diseases, including atrial fibrillation (AF). Reverse transcription-quantitative polymerase chain reaction is a powerful technique to quantitatively assess miRNA expression profile, but reliable results depend on proper data normalization by suitable reference genes. Despite the increasing number of studies assessing miRNAs in cardiac disease, no consensus on the best reference genes has been reached.

Photodamage in deep tissue two-photon optical biopsy of human skin.

Photodamage, induced by femtosecond laser radiation, was studied in thick samples of human skin tissue (healthy skin and neoplastic lesions). Photobleaching, photoionization, and thermomechanical damage effects were characterized comparatively. The laser power dependence of the damage rates allowed to connect macroscopic effects to underlying molecular processes.

Quantification of fibrin in blood thrombi formed in hemodialysis central venous catheters: a pilot study on 43 CVCs.

Purpose: Fibrin deposition and thrombotic occlusion represent a serious cause of access dysfunction in hemodialysis central venous catheters (CVCs). The aim of this work was to define and apply a method for imaging and quantifying fibrin in thrombi formed into the side holes of CVCs.

Methods: Forty-three CVCs removed from a cohort of dialyzed patients were analyzed in this pilot study.

Photoluminescence of hydrophilic silicon nanocrystals in aqueous solutions.

Stable aqueous solutions of undecylenic-acid-grafted silicon nanocrystals (Si-nc) were prepared. The time evolution of the photoluminescence properties of these hydrophilic silicon nanocrystals has been followed on different timescales (hours and days). On a short timescale (hours), Si-nc tend to agglomerate while the PL lineshape and intensity are stable.

Deoxycholate as an efficient coating agent for hydrophilic silicon nanocrystals.

Silicon nanocrystals were made hydrophilic by 10-undecenoic acid grafting and were then coated with sodium deoxycholate, a detergent-like compound belonging to the bile acid class which is crucial for absorption of lipids in the small intestine. The resulting silicon nanocrystals have an average diameter of 3-5 nm, can be dispersed in aqueous solutions and show stable photoluminescence. Coating with non-biological surfactants, which are dangerous for cell safety, was investigated for comparison.

Major phytochemicals in apple cultivars: contribution to peroxyl radical trapping efficiency.

Forty-one samples of apples (peel plus pulp), obtained from eight cultivars, were examined for concentration of some important phytochemicals and for antioxidant activity expressed as peroxyl radical trapping efficiency. Five major polyphenolic groups plus ascorbate were identified and quantified by HPLC in the apple varieties. Oligomeric and polymeric proanthocyanidins were found to be about two-thirds of total polyphenols.