phosphocreatine and glycerophosphoethanolamine

In vivo (31)P spectra were acquired from the human primary visual cortex at 7 T. The relaxation times of the cerebral metabolites, intracellular pH, rate constant (k(f)) of the creatine kinase (CK) reaction, and nuclear Overhauser enhancement (NOE) on the detected phosphorus moieties from irradiation of the water spins were measured from normal subjects. With a 5-cm-diameter surface coil, 3D (31)P chemical shift imaging was performed with a spatial resolution of 7.5 ml and an acquisition resolution of 8 min, resulting in a signal-to-noise ratio (SNR) for phosphocreatine (PCr) resonance of 32. The apparent T(1) and T(2) of PCr measured at 7 T were 3.37 +/- 0.29 s and 132.0 +/- 12.8 ms, respectively, which were considerably longer than those of adenosine triphosphate (ATP) (T(1): 1.02-1.27 s; T(2): 25-26 ms). The NOE measured in this study was 24.3% +/- 1.6% for PCr, and 10% for ATP. The k(f) measured in the human primary visual cortex was 0.24 +/- 0.03 s(-1). The results from this study suggest that ultra-high-field strength is advantageous for performing in vivo (31)P magnetic resonance spectroscopy (MRS) in the human brain.

Topics: Adenosine Triphosphate; Adult; Creatine Kinase; Female; Humans; Magnetic Resonance Spectroscopy; Male; Middle Aged; Phosphatidylcholines; Phosphatidylethanolamines; Phosphocreatine; Reference Values; Visual Cortex

Topics: Adenosine Triphosphate; Creatine Kinase; Humans; Magnetic Resonance Spectroscopy; Phosphatidylcholines; Phosphatidylethanolamines; Phosphocreatine; Reference Values; Visual Cortex

Rat1-T1 and MR1 spheroids represent separate transformed phenotypes originated from the same rat fibroblasts that differ in three-dimensional (3D) growth kinetics, histological structure, and oxygenation status. In the present study, (31)P-NMR spectroscopy of perfused spheroid suspensions was used to investigate cellular energetics relative to 3D growth, development of necrosis, and cell cycle distribution. Both spheroid types were characterized by a remarkably low amount of free (inorganic) phosphate (P(i)) and a low phosphocreatine peak. The ratio of nucleoside triphosphate (NTP) to P(i) ranged between 1.5 and 2.0. Intracellular pH, NTP-to-P(i) ratio, and NTP/cell remained constant throughout spheroid growth, being unaffected by the emergence of oxygen deficiency, cell quiescence, and necrosis. However, a 50% decrease in the ratio of the lipid precursors phosphorylcholine and phosphorylethanolamine (PC/PE) was observed with increasing spheroid size and was correlated with an increased G(1)/G(0) phase cell fraction. In addition, the ratio of the phospholipid degradation products glycerophosphorylcholine and glycerophosphorylethanolamine (GPC/GPE) increased with spheroid diameter in Rat1-T1 aggregates. We conclude that changes in phospholipid metabolism, rather than alterations in energy-rich phosphates, reflect cell quiescence in spheroid cultures, because cells in the inner oxygen-deficient zones seem to adapt their energy metabolism to the environmental conditions before necrotic cell destruction.

Topics: Animals; Cell Division; Cell Line, Transformed; Diffusion Chambers, Culture; Energy Metabolism; Ethanolamines; Fibroblasts; G1 Phase; Glycerylphosphorylcholine; Hydrogen-Ion Concentration; Intracellular Fluid; Magnetic Resonance Spectroscopy; Necrosis; Phosphates; Phosphatidylethanolamines; Phosphocreatine; Phospholipids; Phosphorus Isotopes; Phosphorylcholine; Rats; Rats, Inbred F344; Resting Phase, Cell Cycle; Spheroids, Cellular

To measure inorganic phosphate (Pi), phosphocreatine (PCr), ATP and phosphodiesters (PDE) in fibromyalgic muscle tissue by (31)P magnetic resonance spectroscopy.. A 1.5 Tesla scanner with a P 100 surface coil was used to examine 15 patients (mean age 49.9+/-14.3 yr) with fibromyalgia, according to the American College of Rheumatology criteria, and 17 healthy controls (mean age 30.2+/-5.8 yr).. Compared with the controls, there were increases in the levels of PDE (+22%, P = 0.032) and Pi (+19%, P = 0.019) in the spectra of fibromyalgia patients, but there was no difference in pH.. The metabolic differences we found may have been related to weakness and fatigue in the fibromyalgia patients, but they do not fully explain the fibromyalgia symptoms.

Topics: Adenosine Triphosphate; Adult; Ethanolamines; Female; Fibromyalgia; Glycerylphosphorylcholine; Humans; Magnetic Resonance Spectroscopy; Male; Middle Aged; Muscle, Skeletal; Nucleosides; Phosphates; Phosphatidylethanolamines; Phosphocreatine; Phosphorus; Phosphorylcholine; Reference Values

To evaluate whether decoupling improves signal-to-noise ratio and frequency resolution of in vivo kidney spectra, and to compare native and well-functioning transplant kidneys.. Proton decoupling in conjunction with three-dimensional chemical shift imaging (3D-CSI) in phosphorus-31 magnetic resonance (MR) spectroscopy was used with a spatial resolution of 64 cm3 and 17-minute acquisition time to compare native (n = 10) and well-functioning transplant (n = 9) kidneys.. Proton decoupling improved peak amplitudes by almost 30%, as well as chemical shift resolution of in vivo kidney spectra. No statistically significant differences in phosphometabolite ratios and renal spectra were observed between healthy volunteers and patients with nonrejecting transplants. The phosphodiester-phosphomonoester ratio was 3.02 +/- 0.88, phosphomonoester-inorganic phosphate ratio was 1.07 +/- 0.44, and inorganic phosphate-adenosine triphosphate ratio was 0.58 +/- 0.22 after correction for saturation effects.. Improved spectra of native and transplant kidneys can be obtained in vivo with MR spectroscopy by using a short acquisition time.

Topics: Adenosine Triphosphate; Adult; Glycerylphosphorylcholine; Humans; Image Enhancement; Kidney; Kidney Transplantation; Magnetic Resonance Spectroscopy; Male; Middle Aged; Organophosphates; Phosphates; Phosphatidylethanolamines; Phosphocreatine; Phosphorus; Protons; Signal Processing, Computer-Assisted

Development of biological and clinical uses of in vivo 31P magnetic resonance spectroscopy has been hampered by poor anatomic localization of spectra and poor resolution of overlapping signals within phosphomonoester and phosphodiester regions of the spectrum. We applied 1H-decoupling and nuclear Overhauser enhancement to improve resolution of 31P magnetic resonance spectra accurately localized to 21 non-Hodgkin's lymphomas (NHL) by using three-dimensional chemical shift imaging. All 21 spectra had large phosphomonoester signals (26% of total phosphorus) that contained high amounts of phosphoethanolamine relative to phosphocholine. There were no signals from glycerophosphoethanolamine or glycerophosphocholine but only a broad signal from membrane phospholipids in the phosphodiester region (20% of phosphorus). Prominent nucleoside triphosphates (47% of phosphorus) and low inorganic phosphate (7% of phosphorus) indicate well-perfused tissue with viable cells. Mean intracellular pH was 7.23. These characteristics were similar in all grades and stages of NHL. By analogy with recently reported studies in cell lines in vitro, we hypothesize that the pattern of phospholipid metabolites observed in NHL in vivo is partly a manifestation of sustained activation of phospholipase C or D. The techniques we implemented permitted us to obtain more information about in vivo metabolism of NHL than has heretofore been available. This information is important for the establishment of appropriate experimental models and provides a basis from which to examine potential clinical uses of 31P magnetic resonance spectroscopy.

Topics: 2,3-Diphosphoglycerate; Adult; Aged; Diphosphates; Diphosphoglyceric Acids; Esters; Ethanolamines; Female; Humans; Lymphoma, Non-Hodgkin; Magnetic Resonance Spectroscopy; Male; Middle Aged; Phosphatidylethanolamines; Phosphocreatine; Phosphorylcholine

Nuclear Overhauser effect (NOE) enhancements and relaxation times of 31P metabolites in human calf were measured in 12 volunteers (4 men and 8 women) at 1.5 T using a dual tuned four-ring birdcage. The NOE enhancements of inorganic phosphate (Pi), phosphocreatine (PCr), gamma-, alpha-, and beta-nucleoside triphosphate (NTP) from 19 measurements were 0.51 +/- 0.10, 0.64 +/- 0.03, 0.53 +/- 0.03, 0.56 +/- 0.08, and 0.47 +/- 0.05, respectively. The relaxation times were independent of proton irradiation and from 23 measurements were 3.49 +/- 0.35, 4.97 +/- 0.58, 4.07 +/- 0.36, 2.90 +/- 0.25, and 3.61 +/- 0.25 s for Pi, PCr, gamma-, alpha-, and beta-NTP, respectively. No significant differences between gender and age were observed for either NOE enhancements or relaxation times. Also, among nine volunteers, we observed no significant differences in T1 between the coupled and decoupled cases.

Topics: Adolescent; Adult; Female; Glycerylphosphorylcholine; Humans; Image Enhancement; Leg; Magnetic Resonance Spectroscopy; Male; Middle Aged; Muscle, Skeletal; Nucleotides; Phosphates; Phosphatidylethanolamines; Phosphocreatine; Phosphorus; Phosphorus Isotopes

This study investigates the potential of in vivo 31P magnetic resonance spectroscopy (MRS) to characterize musculoskeletal tumors and to determine preoperative levels of histological necrosis, which is an important clinical indicator of patient response. Pretherapy MRS was performed on 28 patients with large musculoskeletal tumors: 13 with osteosarcoma, 3 with chondrosarcoma, 5 with malignant fibrous histiocytoma, 1 with desmoid tumor, 1 with Ewing's, 2 with hemangioendothelioma, 1 with myxoid liposarcoma, 1 with synovial cell sarcoma, and 1 with rhabdomyosarcoma. Fifteen patients had follow-up MRS examinations after commencement of chemotherapy (mean of five/patient), eight of whom have now had surgery. Elevated levels of PMEs (P < 0.01), P(i) (P < 0.01), and PDEs (P < 0.02) as well as elevated tumor pH (P < 0.05) were observed in all patients. The synovial cell sarcoma was characterized by high levels of PMEs (> 20%) and low pH (pH 6.76). This contrasted with the spectra obtained from the malignant fibrous histiocytomas which had high levels of PDEs (17 +/- 5%). Reductions in PDE levels postchemotherapy were associated with a high degree of necrosis (> 90%) at surgery, while an increase in PDE levels was associated with a low level of histological necrosis. Likewise, reductions in the ratios PDE/NTP and PDE/PCr and an increase in P(i)/PDE were also associated with a high level of necrosis.

Topics: Adult; Aged; Bone Neoplasms; Chemotherapy, Adjuvant; Ethanolamines; Female; Glycerylphosphorylcholine; Humans; Magnetic Resonance Spectroscopy; Male; Middle Aged; Muscular Diseases; Necrosis; Neoplasm Staging; Neoplasms; Osteosarcoma; Phosphatidylethanolamines; Phosphocreatine; Phosphorus; Phosphorylcholine; Preoperative Care