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Single-voxel proton spectra of the human brain were recorded in five subjects at both 1.5T and 3.0T using the STEAM pulse sequence. Data acquisition parameters were closely matched between the two field strengths. Spectra were recorded in the white matter of the centrum semiovale and in phantoms. Spectra were compared in terms of resolution and(More)
The goal of these experiments was to investigate the relationship of ATP, phosphocreatine (PCr), inorganic phosphate (Pi), monobasic phosphate (H2PO4-), and pH to human muscle fatigue. Phosphates and pH were measured in adductor pollicis using 31P nuclear magnetic resonance at 2.0 Tesla. The force of muscle contraction was simultaneously measured with a(More)
  • M Boska
  • 1994
Net forward adenosine triphosphate (ATP) production rates were calculated from 31P nuclear magnetic resonance spectroscopy (MRS) kinetic data collected with 1-8 s time resolution during isometric voluntary contractions of the human gastrocnemius/soleus muscle group. Volume normalized muscle output (Newtons/ml) was then divided by the calculated net ATP use(More)
Net ATP production rates in exercising human muscle were calculated from 31P MRS kinetic data collected with 1-8 s time resolution. During the exercise, the muscle output was measured using a force transducer. Muscle output (force/unit volume) is then divided by the calculated net ATP used to estimate the ATP cost of force production. These measurements(More)
This study has measured the apparent 31P T1 times at 1.5 T in human gastrocnemius/soleus muscle groups at rest, during exercise, and during recovery from a 90-sec submaximal plantar flexion exercise. T1 times were measured with a 10-sec time resolution in 11 normally active volunteers using a surface coil with a nine-point progressive saturation technique.(More)
Measurements of adenosine triphosphate (ATP) production rates, metabolic economy, intracellular pH, phosphodiesters, and phosphomonoesters along with the force output were used to study 90-s maximum voluntary contractions and two new exercise protocols (20-10 and 30-16 exercises). The 20-10 exercise consisted of thirty-one 20-s maximal voluntary(More)
We investigated the metabolic basis of human muscular fatigue and recovery utilizing 31P magnetic resonance spectroscopy and measurements of maximum voluntary contraction (MVC). We produced fatigue by sustained MVC for 4 minutes in 2 different muscles (adductor pollicis, tibialis anterior) and obtained similar results in both muscles. During fatiguing(More)
Neuroinflammatory processes play a significant role in the pathogenesis of Parkinson's disease (PD). Epidemiologic, animal, human, and therapeutic studies all support the presence of an neuroinflammatory cascade in disease. This is highlighted by the neurotoxic potential of microglia . In steady state, microglia serve to protect the nervous system by acting(More)
T1 and magnetization transfer at a field strength of 7 Tesla were used to discriminate between water accumulation and protein mobilization in tissue undergoing infarction. Twelve rats subjected to acute stroke via intralumenal suture occlusion of the middle cerebral artery, and 19 controls, were studied. In MRI studies to 6 hr post-ictus, serial data(More)
We examined the relationships between muscle force and both phosphate and hydrogen ion concentrations in muscles with differential fatigability and in different types of exercise. We measured force and 31phosphorus nuclear magnetic resonance spectra from the tibialis anterior (a slow-contracting, fatigue resistant, postural leg muscle) during a sustained(More)