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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

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

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

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

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 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

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

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

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

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

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

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

One-neutron removal cross-sections (σ-1n) of 17,19C in various targets at about 900 MeV/nucleon, and one-proton removal cross-sections (σ-1p) of 8,10B at about 1400 MeV/nucleon were measured using the fragment separator FRS at GSI. A significant increase of σ-1n for 19C compared to its neighbors was observed. The same behavior was found for σ-1p for the neutron-deficient nucleus 8B compared to the

The technique of intensity interferometry is proposed as a probe of the spatial configuration of two-Neutron haloes. After exploring the sensitivity of interferometry to the n-N configuration, it is demonstrated that the application of the standard method for constructing the correlation function is not valid for halo neutrons. A new iterative method is presented and applied to measurements of the

The longitudinal momentum distribution of Be fragments after fragmentation of B and the one-proton removal cross section (σ-1p) in a carbon target were measured at 1440 MeV/u with the fragment separator FRS used as an energy-loss spectrometer. The results show a narrow momentum distribution with a FWHM value of 91 ± 5 MeV/c and a large cross-section, σ-1p = 98 ± 6 mb. Both these results support th

The fragment separator FRS at GSI was used as an energy-loss spectrometer to study the nuclear structure of exotic light nuclei via nucleon-removal reactions. The measurements performed include the longitudinal momentum distributions of fragments after one-nucleon removal, the one-nucleon removal cross-sections and in some cases the coincident detection of gamma rays emitted from the breakup fragm

The fragment separator FRS at GSI was used as an energy-loss spectrometer to measure the longitudinal momentum distributions of 16,18C fragments after one-neutron removal reactions in 17,19C impinging on a carbon target at about 910 MeV/u. The distributions in the projectile frames are characterized by a FWHM of 141 ± 6 MeV/c for 16C and 69 ± 3 MeV/c for 18C. The results are compared with experime

The excitation functions for elastic α-particle scattering by 12C, 16O, 18O, and 20Ne at 180° in the c.m.s. are determined in wide energy ranges by using the new method of elastic resonance scattering on a thick target in inverse kinematics. In favorable cases, the method makes it possible to reduce considerably the time required for obtaining excitation curves. General regularities observed in th