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In situ light dosimetry during whole bladder wall photodynamic therapy : clinical results and experimental verification

Photodynamic therapy (PDT) using Photofrin IIR (PII) as a photosensitizer is currently being evaluated as a new treatment modality for superficial bladder cancer. An optimum therapeutic ratio requires uniform illumination of the whole bladder wall and accurate light dosimetry. The first clinical light dosimetry results (16 patients) are reported, obtained using a system which allows in situ measur

On the Fourier dimension and a modification

We give a sufficient condition for the Fourier dimension of a countable union of sets to equal the supremum of the Fourier dimensions of the sets in the union, and show by example that the Fourier dimension is not countably stable in general. A natural approach to finite stability of the Fourier dimension for sets would be to try to prove that the Fourier dimension for measures is finitely stable,

Global HDO uptake in human glioma xenografts is related to the perfused capillary distribution

The aim of this study is to evaluate the existence of a possible relationship between global deuterium-labeled water (HDO) uptake rates and the diffusion geometry of human glioma xenografts in nude mice. HDO diffusion times in the whole extravascular tumor volume were estimated by combining quantitative (1)H-MR diffusion imaging and morphometric analysis of intercapillary distances in two tumor li

Effects of ischemia on skeletal muscle energy metabolism in mice lacking creatine kinase monitored by in vivo 31P nuclear magnetic resonance spectroscopy

The aim of this study was to provide in vivo experimental evidence for the proposed biological significance of the creatine kinase (CK)/phosphocreatine (PCr) system in the energy metabolism of skeletal muscle. As a test system we compared hindlimb muscle of knockout mice lacking the cytosolic M-type (M-CK(-)/(-)), the mitochondrial ScMit-type (ScCKmit(-)/(-)), or both creatine kinase isoenzymes (C

Proton MR spectroscopy of wild-type and creatine kinase deficient mouse skeletal muscle : dipole-dipole coupling effects and post-mortem changes

Localized proton MR spectra of mouse skeletal muscle obtained at 7 T show dipole-dipole coupling effects for creatine and putative taurine resonances and for the lactate methine signal. These effects are independent of the presence of creatine kinase. The intensity of the methylene (1)H resonance of creatine is not different between wild-type and creatine kinase deficient mice, which have a lower

Introduction to in vivo 31P magnetic resonance spectroscopy of (human) skeletal muscle

31P magnetic resonance spectroscopy (MRS) offers a unique non-invasive window on energy metabolism in skeletal muscle, with possibilities for longitudinal studies and of obtaining important bioenergetic data continuously and with sufficient time resolution during muscle exercise. The present paper provides an introductory overview of the current status of in vivo 31P MRS of skeletal muscle, focusi

Automatic correction for phase shifts, frequency shifts, and lineshape distortions across a series of single resonance lines in large spectral data sets

A new model-free method is presented that automatically corrects for phase shifts, frequency shifts, and additional lineshape distortions of one single resonance peak across a series of in vivo NMR spectra. All separate phase and frequency variations are quickly and directly derived from the common lineshape in the data set using principal component analysis and linear regression. First, the new a

Common processing of in vivo MR spectra

This introductory article addresses approaches currently in use to process in vivo spectra. First, a brief overview is given of the information content represented by the parameters of MR signals. Subsequently, common steps in the processing of MR spectra such as pre-processing, normalisation and quantification and the use of prior knowledge are described. Finally, some prospects for more advanced

Creatine kinase B-driven energy transfer in the brain is important for habituation and spatial learning behaviour, mossy fibre field size and determination of seizure susceptibility

Creatine kinases are important in maintaining cellular-energy homeostasis, and neuroprotective effects have been attributed to the administration of creatine and creatine-like compounds. Herein we examine whether ablation of the cytosolic brain-type creatine kinase (B-CK) in mice has detrimental effects on brain development, physiological integrity or task performance. Mice deficient in B-CK (B-CK

Presence of (phospho)creatine in developing and adult skeletal muscle of mice without mitochondrial and cytosolic muscle creatine kinase isoforms

We assessed the relationship between phosphocreatine (PCr) and creatine (Cr) content and creatine kinase (CK) activity in skeletal muscle of mice. The PCr and total Cr (tCr) concentrations, as well as CK activity, in hindlimb muscles of mice, with or without the cytosolic and mitochondrial isoforms of muscle creatine kinase (wild-type or CK--/-- mice), were determined by in vivo magnetic resonance

Cerebral creatine kinase deficiency influences metabolite levels and morphology in the mouse brain : a quantitative in vivo 1H and 31P magnetic resonance study

Creatine kinase (CK)-catalysed ATP-phosphocreatine (PCr) exchange is considered to play a key role in energy homeostasis of the brain. This study assessed the metabolic and anatomical consequences of partial or complete depletion of this system in transgenic mice without cytosolic B-CK (B-CK-/-), mitochondrial ubiquitous CK (UbCKmit-/-), or both isoenzymes (CK -/-), using non-invasive quantitative

Scarred Uterus: Subsequent Pregnancy and Delivery

The aim of the work presented in this thesis was to address the problems associated with the management of pregnancy and delivery after Caesarean delivery (CD), with emphasis on ultrasound diagnostics. The prognostic value and utility of serial ultrasound examinations of Caesarean hysterotomy scars in the non-pregnant state and during pregnancy subsequent to CD were studied. This thesis includes 5

Self-gated fetal cardiac MRI with tiny golden angle iGRASP : A feasibility study

PURPOSE: To develop and assess a technique for self-gated fetal cardiac cine magnetic resonance imaging (MRI) using tiny golden angle radial sampling combined with iGRASP (iterative Golden-angle RAdial Sparse Parallel) for accelerated acquisition based on parallel imaging and compressed sensing.MATERIALS AND METHODS: Fetal cardiac data were acquired from five volunteers in gestational week 29-37 a

Effects of caffeine abstinence on adenosine induced coronary flow reserve quantified on phase contrast velocity encoded MRI of the coronary sinus

Introduction: Adenosine is a common pharmacological vasodilator agent used in first pass perfusion MRI as well as nuclear cardiology and echocardiography. Coronary flow reserve (CFR) by adenosine is inhibited by caffeine and therefore caffeine abstinence is routinely proscribed in patients. However, the guidelines differ regarding how long abstinence is needed from 12 to 24 hours. Purpose: This st

Experimental evidence for the 8B ground state configuration

The 7Be fragments produced in one-proton removal from relativistic 8B nuclei of 936 MeV/nucleon in a carbon target have been detected in coincidence with γ rays emitted by these fragments at the reaction target. It is found that 13 ± 3% of the 7Be fragments are released in the 429 keV excited state, 7Be*, which gives direct experimental information on the ground state configuration of 8B. The long