Search results for " Enhancement"

A fully automated method for accurate measurement of geometrical distortion in magnetic resonance imaging of a 3D-lattice phantom

2019

Abstract This paper describes an automated method for extracting the apparent positions of fiducial points from 2D or 3D images of a phantom. We consider a 3D-lattice phantom for two main reasons: first, ease of manufacture and isotropy of its structure with respect to coordinate projections; second, a connected structure allowing to uniquely assess the adjacency relationship between fiducial points even if geometric distortions arising from main magnet inhomogeneity and gradient fields non-linearity is severe as observed in open-bore systems. In order to validate our proposed method and compare different choices for the parameters of our phantom (i.e. number and distance between grids and …

Radiomic analysis reveals DCE-MRI features for prediction of molecular subtypes of breast cancer.

2017

The purpose of this study was to investigate the role of features derived from breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and to incorporated clinical information to predict the molecular subtypes of breast cancer. In particular, 60 breast cancers with the following four molecular subtypes were analyzed: luminal A, luminal B, human epidermal growth factor receptor-2 (HER2)-over-expressing and basal-like. The breast region was segmented and the suspicious tumor was depicted on sequentially scanned MR images from each case. In total, 90 features were obtained, including 88 imaging features related to morphology and texture as well as dynamic features from tumor and …

Erythropoietin to treat anaemia in patients with head and neck cancer

2004

based on the improvement of tumour oxygenation through direct effects (oxygen enhancement effect of radiotherapy) and indirect effects (counteraction of the adverse influence of tumour hypoxia on malignant progression), only increases in haemoglobin concentration that result in improvements in tumour oxygenation can be expected to have a favourable effect on prognosis. The haemoglobin concentration range leading to the highest tumour oxygen levels is most probably between 130 and 140 g/L, since this concentration represents an optimum in terms of the counteracting effects of increasing the blood’s oxygen-carrying capacity and rising viscous resistance to flow. At higher haemoglobin concentr…

Gold Nanoparticle-Assisted Virus Formation by Means of the Delivery of an Oncolytic Adenovirus Genome

2020

[EN] Oncolytic adenoviruses are a therapeutic alternative to treat cancer based on their ability to replicate selectively in tumor cells. However, their use is limited mainly by the neutralizing antibody (Nab) immune response that prevents repeated dosing. An alternative to facilitate the DNA access to the tumor even in the presence of anti-viral Nabs could be gold nanoparticles able to transfer DNA molecules. However, the ability of these nanoparticles to carry large DNA molecules, such as an oncolytic adenovirus genome, has not been studied. In this work, gold nanoparticles were functionalized with different amounts of polyethylenimine to transfer in a safe and efficient manner a large on…

In-vivo-Konfokalmikroskopie in der Diagnose des okulären Schleimhautpemphigoids

2015

Hintergrund: Fur die Prognose des okularen Schleimhautpemphigoids (mucous membrane pemphigoid, MMP) ist eine fruhe Diagnosesicherung essenziell. Allerdings wird die Sensitivitat des sog. diagnostischen Goldstandards, der direkten (DIF) bzw. indirekten Immunfluoreszenz (IIF) mit einer Spanne von 30–80 % sehr variabel angegeben. Zusatzlich birgt die dafur notwendige Bindehautbiopsie die Gefahr der Exazerbation. Ziel dieser Studie war es, zu ermitteln, ob die nicht invasive In-vivo-Konfokalmikroskopie zur Erkennung eines okularen Schleimhautpemphigoids beitragen kann. Patienten und Methoden: Die Konjunktiva von 10 Pemphigoidpatienten und 10 Kontrollprobanden wurden mithilfe des o. g. Verfahren…

Spectral-Domain optische Kohärenztomografie (SD-OCT) bei chirurgischer Behandlung einer Makulopathie bei Grubenpapille

2016

Sputtered cuprous oxide thin films and nitrogen doping by ion implantation

2016

Abstract The structural, optical and electrical properties of sputtered cuprous oxide thin films have been optimized through post-deposition thermal treatments. Moreover we have studied the effects of nitrogen doping introduced by ion implantation followed by the optimized oxidant thermal annealing. Three concentrations have been used, 0.6 N%, 1.2 N%, and 2.5 N%. Along with the preservation of the Cu 2 O phase, a slight optical band gap narrowing and a significant conductivity enhancement has been observed with respect to the undoped samples. These results can be justified by the absence of further oxygen vacancies promoted by dopant introduction and by the substitution of O atoms by N ones…

Intravitreal delivery of AAV-NDI1 provides functional benefit in a murine model of Leber hereditary optic neuropathy.

2012

Leber hereditary optic neuropathy (LHON) is a mitochondrially inherited form of visual dysfunction caused by mutations in several genes encoding subunits of the mitochondrial respiratory NADH-ubiquinone oxidoreductase complex (complex I). Development of gene therapies for LHON has been impeded by genetic heterogeneity and the need to deliver therapies to the mitochondria of retinal ganglion cells (RGCs), the cells primarily affected in LHON. The therapy under development entails intraocular injection of a nuclear yeast gene NADH-quinone oxidoreductase (NDI1) that encodes a single subunit complex I equivalent and as such is mutation independent. NDI1 is imported into mitochondria due to an e…

Naked DNA delivery to whole pig cardiac tissue by coronary sinus retrograde injection employing non-invasive catheterization.

2010

Background Hydrodynamic injection has demonstrated to be very efficient in the liver of small animals, although this procedure must be translated to the clinical practice in a milder but no less efficient way. The present study evaluates the capacity of non-invasive interventional catheterization as a procedure for naked DNA delivery to the heart in large animals. Methods Two catheters were placed in the coronary sinus: one of them to block blood circulation and the other to retrogradely inject 50 ml of a saline solution of DNA (20 µg/ml) containing the enhanced green fluorescent protein (EGFP) gene, at a flow rate of 5 ml/s. Results The results obtained show that EGFP protein, identified b…

Chromoendoscopy and Other Novel Imaging Techniques

2006

The newly developed high-resolution and magnification endoscopes offer features that allow more and new mucosal details to be seen. They are commonly used in conjunction with chromoendoscopy. The analysis of mucosal surface details is beginning to resemble histologic examination. More accurate recognition of small flat and depressed neoplastic lesions is possible. Endoscopic prediction of neoplastic and nonneoplastic tissue is possible by analysis of surface architecture of the mucosa, which influences the endoscopic management. For the diagnosis of flat adenomas, chromoendoscopy should be a part of the endoscopist's armamentarium. In inflammatory bowel disease, chromoendoscopy can be used …