Search results for "tomography"

Sepsis in head and neck cancer patients treated with chemotherapy and radiation: literature review and consensus

2015

Abstract: The reporting of infection/sepsis in chemo/radiation-treated head and neck cancer patients is sparse and the problem is underestimated. A multidisciplinary group of head and neck cancer specialists from Italy met with the aim of reaching a consensus on a clinical definition and management of infections and sepsis. The Delphi appropriateness method was used for this consensus. External expert reviewers then evaluated the conclusions carefully according to their area of expertise. The paper contains seven clusters of statements about the clinical definition and management of infections and sepsis in head and neck cancer patients, which had a consensus. Furthermore, it offers a revie…

X-ray Computed Tomography for Capillary Collapse of Loose Unsaturated Sand

2016

Abstract The collapse of unsaturated soils consists of the reduction in volume upon wetting at constant total stress. Several studies at the macro scale outline the influence of initial void ratio, confining pressure and matric suction on the onset of collapse of standard laboratory specimens. Conversely, few observations at the micro scale are available in the literature, although the influence of the particles arrangement and intergranular bonding has been formerly supposed. The collapse of fine sand derived by a pyroclastic soil of Southern Italy is investigated in this paper at the microscale using the X-ray Computed Tomography. The experimental procedure, formerly tested on similar pyr…

A Novel 68Ga-Labeled Pteroic Acid-Based PET Tracer for Tumor Imaging via the Folate Receptor

2012

The folate receptor (FR) is a very attractive target in oncological imaging as it is overexpressed by a variety of cancer types, whereas the expression in healthy tissue is very limited. The synthesis of regioisomeric pure folic acid derivatives normally requires a regioselective approach and does not allow the use of native folic acid (FA). As the pharmacophore of FA is assumed to be pteroic acid, its use without the glutamic acid moiety may enable the possibility to considerably simplify the synthesis of a positron emission tomography (PET) tracer for FR imaging. In this work, DO3A-EA-Pte was successfully synthesized and labeled with 68Ga. It is stable for up to 3 h in PBS and against tra…

Radioactive labeling of defined HPMA-based polymeric structures using [18F]FETos for in vivo imaging by positron emission tomography.

2009

During the last decades polymer-based nanomedicine has turned out to be a promising tool in modern pharmaceutics. The following article describes the synthesis of well-defined random and block copolymers by RAFT polymerization with potential medical application. The polymers have been labeled with the positron-emitting nuclide fluorine-18. The polymeric structures are based on the biocompatible N-(2-hydroxypropyl)-methacrylamide (HPMA). To achieve these structures, functional reactive ester polymers with a molecular weight within the range of 25,000-110,000 g/mol were aminolyzed by 2-hydroxypropylamine and tyramine (3%) to form (18)F-labelable HPMA-polymer precursors. The labeling procedure…

Radiolabeling of DOTATOC with the long-lived positron emitter 44Sc.

2010

Abstract The positron-emitting radionuclide 44 Sc with a half-life of 3.97 h and a β + branching of 94.3% is of potential interest for clinical PET. As so far it is available from a 44 Ti/ 44 Sc generator in Mainz, where long-lived 44 Ti decays to no-carrier-added (nca) 44 Sc. The 44 Sc is a trivalent metal cation and should be suitable for complexation with many well established bifunctional chelators conjugated to peptides or other molecular targeting vectors. Thus, the aim of this work was to investigate the potential of 44 Sc for labeling of DOTA-conjugated peptides. DOTA-D-Phe 1 -Tyr 3 -octreotide (DOTATOC) was used as a model molecule to study and optimize labeling procedure. Reaction…

Maturation of a Key Resource – The Germanium-68/Gallium-68 Generator: Development and New Insights

2011

(68)Ge/(68)Ga radionuclide generators have been investigated for almost fifty years, since the cyclotron-independent availability of positron emitting (68)Ga via the (68)Ge/(68)Ga system had always attracted researches working in basic nuclear chemistry as well as radiopharmaceutical chemistry. However, it took decades and generations of research (and researchers) to finally reach a level of (68)Ge/(68)Ga radionuclide generator designs adequate to the modern requirements of radiometal labelling chemistry. Nevertheless, most of the existing commercial generator systems address aspects of (68)Ge breakthrough and safe synthesis of (68)Ga radiopharmaceuticals by adopting eluate post-processing …

Relationship of choroidal thickness with pulsatile hemodynamics in essential hypertensive patients

2021

Controversy exists about the association of choroidal thickness (CTh) with blood pressure (BP) values. There is some evidence suggesting that central hemodynamics changes are associated with microvascular disease. Our study was aimed to assess the relationships between CTh and clinic and 24-h BP and between CTh and estimated 24-h aortic pulse pressure (aPP), 24-h aortic systolic BP (aSBP), and 24-h aortic augmentation index (aAIx) in a group of hypertensive patients. We enrolled 158 hypertensive subjects (mean age 48 ± 13 years) all of which underwent evaluation of the choroidal district by Swept-Source optical coherence tomography (SS-OCT) and 24-h BP monitoring, in order to measure periph…

Third molar surgical difficulty scales: systematic review and preoperative assessment form

2021

Background The main objective of this systematic review was to collect the pre-existing scales for assessing the difficulty of third molar extraction. The secondary objective was to design a proposal for a preoperative evaluation protocol for the difficulty of third molar extraction. Material and Methods Two independent researchers conducted an electronic search in Pubmed (MEDLINE), Cochrane, and Scopus databases during March 2021. Included studies evaluated the prediction of the difficulty of surgical removal of impacted upper or lower third molars using new indices/scales or pre-existing scales with or without modifications. Articles referring to coronectomies or assessing pre-surgical di…

Collateral findings at 40-slices computed tomography enteroclysis

2006

Applied neutron tomography in modern archaelogy

2007

The use of neutron tomography for archaeometric purposes is quite a new technique. The property of neutron to transmit easily large, dense samples is of great importance in modern archaeology. The three-dimensional visualisation of the inner structure of samples of archaeological interest helps to make suggestions about the technological process of manufacturing or reveals information about the origins of delivering of noble materials used in ancient masterpieces. Another application field in modern archaeology is the non-destructive inspection of the quality of specimen conservation where the neutron tomography allows visualization of impregnation solutions in wood or metal matrices. The h…