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A novel approach is presented for imaging macromolecule and metabolite signals in brain by proton magnetic resonance spectroscopic imaging. The method differentiates between metabolites and macromolecules by T1 weighting using an inversion pulse followed by a variable inversion recovery time before localization and spectroscopic imaging. In healthy(More)
Proton magnetic resonance spectroscopy (MRS) signals from lipids in brain have been observed to increase after ischemic brain injury. However, neither the chemical identity nor the cellular location of these lipids has been established. The aim of the present study was to identify the origin of MRS lipid signals in rat brain after temporary (90 min) middle(More)
BACKGROUND AND PURPOSE We sought to measure the temporal evolution and spatial distribution of lesion macromolecules and small molecules (lactate, N-acetyl compounds, creatine, and choline) in stroke patients by using short echo time in vivo proton MR spectroscopy. METHODS Single-voxel spectra with TE=22 ms were obtained with and without inversion(More)
We present a series of measurements based on K L,S →␲ ϩ ␲ Ϫ and K L,S →␲ 0 ␲ 0 decays collected in 1996 – 1997 by the KTeV experiment ͑E832͒ at Fermilab. We compare these four K→␲␲ decay rates to measure the direct CP violation parameter Re(⑀Ј/⑀)ϭ(20.7Ϯ2.8)ϫ10 Ϫ4. We also test CPT symmetry by measuring the relative phase between the CP violating and CP(More)
BACKGROUND AND PURPOSE Proton magnetic resonance spectroscopy can measure in vivo brain lactate and other metabolites noninvasively. We measured the biochemical changes accompanying stroke in 16 human subjects with cortical or deep cerebral infarcts within the first 3 weeks after symptom onset, and performed follow-up studies on six. METHODS(More)
Previous studies of human stroke by 1H nuclear magnetic resonance spectroscopy have shown elevation of lactate lasting 3 to 6 months. Complete metabolic turnover of the elevated lactate pool has been demonstrated 5 weeks after a stroke. Its cellular localization is among the first questions requiring clarification. Information pertinent to this question(More)
To evaluate MRI methods for estimating cerebrovascular reserve, we computed changes in the R2* and R2 transverse relaxation rate and apparent diffusion coefficient (ADC) at 2.0 Tesla in five rats after administration of 30 mg of acetazolamide and in four rats during inhalation of 20% carbon dioxide gas. Significant decreases in R2*, corresponding to(More)
The design of pharmacokinetic and pharmacodynamic experiments concerns a number of issues, among which are the number of observations and the times when they are taken. Often a model is used to describe these data and the pharmacokinetic-pharmacodynamic behavior of a drug. Knowledge of the data analysis model at the design stage is beneficial for collecting(More)
We studied two patients with Creutzfeldt-Jakob disease by in vivo proton magnetic resonance spectroscopy and obtained spectra from an extract of biopsy tissue from a third patient. In vivo spectra from the two patients, 3 months and less than 1 month after symptom onset, revealed only minor changes. A second study of one of the patients 10 months after(More)
This paper presents a method for optimal design of multiresponse population pharmacokinetic experiments taking into account correlations between interindividual variances. Expressions for the population Fisher information matrix have been defined for uniresponse and multiresponse pharmacokinetic experiments. A major assumption often made is that the(More)