Home About us Contact
|
Home About us Contact | ||
|
|
||
Resonance Spectroscopy Study (resonance + spectroscopy_study)
Kinds of Resonance Spectroscopy Study Selected AbstractsA Proton Magnetic Resonance Spectroscopy Study of Metabolites in the Occipital Lobes in EpilepsyEPILEPSIA, Issue 4 2003Robert J. Simister Summary: ,Purpose: ,-Amino butyric acid (GABA) and glutamate, respectively the principal inhibitory and excitatory neurochemicals in the brain, are visible to proton magnetic resonance spectroscopy (MRS). We report a study of GABA+ (GABA plus homocarnosine) and GLX (glutamate plus glutamine) concentrations in the occipital lobes in patients with idiopathic generalised epilepsy (IGE) and in patients with occipital lobe epilepsy (OLE). Methods: Fifteen patients with IGE, 15 patients with OLE, and 15 healthy volunteers were studied. A single voxel was prescribed in the occipital lobes for each subject. PRESS localised short-echo-time MRS was performed to measure GLX by using LCModel. A double quantum GABA filter was used to measure GABA+. Segmented T1 -weighted images gave the tissue composition of the prescribed voxel. Results: Grey-matter proportion, GLX, and GABA+ were all elevated in IGE. However, analysis using grey-matter proportion as a covariable showed no significant group differences. No correlation was observed between GABA+ concentration and either seizure frequency or time since last seizure. Conclusions: GLX and GABA+ were elevated in IGE. Elevated grey-matter content in the IGE group despite normal MRI appearance can be expected to account for some or all of this observed elevation of GLX and GABA+. GABA+ concentration did not correlate with seizure control or duration since most recent seizure. [source] Effects of Abstinence From Alcohol on the Broad Phospholipid Signal in Human Brain: An In Vivo 31P Magnetic Resonance Spectroscopy StudyALCOHOLISM, Issue 8 2001M. R. Estilaei Background: In vivo phosphorus magnetic resonance spectroscopy (31P MRS) at a magnetic field strength of 1.5 T allows measurement of fairly mobile membrane phospholipids in the human brain. We previously showed that subjects who are heavy drinkers had a smaller signal and a shorter transverse relaxation time (T2) of white matter phospholipids than light drinkers, which suggested lower concentrations and molecular mobility of phospholipids in heavy drinkers. The purpose of the present study was to measure if such chronic alcohol-induced white matter tissue changes are persistent in long-term abstinent alcoholics. Methods: Fourteen abstinent alcoholics (mean age 45 years, seven men and seven women) were studied by localized 31P MRS in the centrum semiovale and were compared with 13 male, alcohol-dependent, heavy drinkers and 23 nondependent light drinkers (17 men, 6 women) of similar age. Methods for measurements of the broad membrane phospholipid signal and its relaxation time were described previously. Results: Phospholipid concentrations and relaxation times in alcoholics abstinent for an average of 31 months were not significantly different from those measured in light drinkers. The contribution of fast and slowly relaxing signal components to the broad phospholipid signal, however, was still different in abstinent alcoholics compared with light drinkers. No effects of sex or of family history of alcoholism were noted on any of our spectroscopic measures within the light-drinking or abstinent groups. Conclusions: Most of our results suggest at least partial recovery of chronic alcohol-induced white matter phospholipid damage with long-term abstinence. They offer myelination changes and/or dendritic rearborization as a possible mechanism for the commonly observed white matter volume gain with prolonged abstinence. But the results also suggest a persistent abnormality in the nature and/or physical properties of white matter phospholipids in long-term abstinent alcoholics. [source] 31Phosphorus magnetic resonance spectroscopy study of tissue specific changes in high energy phosphates before and after sertraline treatment of geriatric depressionINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2009Brent P. Forester Abstract Introduction We investigated tissue specific differences in markers of energy metabolism, including high energy phosphate compounds (beta and total NTP, PCr) and pH, in older adults with depression compared with healthy controls, before and after a 12-week treatment trial of sertraline. Methods Thirteen older adults, age ,55, with Major Depressive Disorder (HAMD17 score of ,18) were recruited along with ten age-matched controls. The depression subjects had a pre- and post-treatment 4T 31P-MRS scan using a three-dimensional chemical shift imaging sequence. The extracted brain images were segmented into white matter (WM), gray matter (GM) and CSF. A linear mixed effects model analyzed the effects of pre-treatment and post-treatment depression on phosphorus metabolite concentration estimates (including calculated pH and Mg++). Results Total tissue beta-NTP (,8%, t(18.66),=,3.50; p,=,0.0024) and total tissue total NTP (,6%, t(17.41),=,2.68; p,=,0.0156) were lower in subjects with geriatric depression compared with healthy controls. Total tissue levels of total-NTP changed significantly with treatment (,2%, t(14.84),=,,2.47; p,=,0.0259). Total NTP was reduced in the WM, but not the GM, in the pre-treatment depression group (t(51.65),=,4.02; p,=,0.0002). Intracellular pH was higher in the GM of subjects with pre-treatment depression (t(1133.84),=,,2.10; p,=,0.0353) and decreased to approximate control levels after treatment (t(648.86),=,,2.53; p,=,0.0115). Discussion These findings demonstrate bioenergetic changes including tissue specific differences in 31P-MRS metabolites in geriatric depression. Decreased white matter total NTP may reflect alterations in white matter function. Copyright © 2009 John Wiley & Sons, Ltd. [source] NMR-based metabonomics analysis of mouse urine and fecal extracts following oral treatment with the broad-spectrum antibiotic enrofloxacin (Baytril)MAGNETIC RESONANCE IN CHEMISTRY, Issue S1 2009Lindsey E. Romick-Rosendale Abstract The human gastrointestinal tract is home to hundreds of species of bacteria and the balance between beneficial and pathogenic bacteria plays a critical role in human health and disease. The human infant, however, is born with a sterile gut and the complex gastrointestinal host/bacterial ecosystem is only established after birth by rapid bacterial colonization. Composition of newborn gut flora depends on several factors including type of birth (Ceasarian or natural), manner of early feeding (breast milk or formula), and exposure to local, physical environment. Imbalance in normal, healthy gut flora contributes to several adult human diseases including inflammatory bowel (ulcerative colitis and Crohn's disease) and Clostridium difficile associated disease, and early childhood diseases such as necrotizing enterocolitis. As a first step towards characterization of the role of gut bacteria in human health and disease, we conducted an 850 MHz 1H nuclear magnetic resonance spectroscopy study to monitor changes in metabolic profiles of urine and fecal extracts of 15 mice following gut sterilization by the broad-spectrum antibiotic enrofloxacin (also known as Baytril). Ten metabolites changed in urine following enrofloxacin treatment including decreased acetate due to loss of microbial catabolism of sugars and polysaccharides, decreased trimethylamine- N -oxide due to loss of microbial catabolism of choline, and increased creatine and creatinine due to loss of microbial enzyme degradation. Eight metabolites changed in fecal extracts of mice treated with enrofloxacin including depletion of amino acids produced by microbial proteases, reduction in metabolites generated by lactate-utilizing bacteria, and increased urea caused by loss of microbial ureases. Copyright © 2009 John Wiley & Sons, Ltd. [source] Preinvasive and invasive cervical cancer: an ex vivo proton magic angle spinning magnetic resonance spectroscopy studyNMR IN BIOMEDICINE, Issue 3 2004Marrita M. Mahon Abstract The aim of this study was to obtain 1H MR spectra using magic angle spinning (MAS) techniques from punch biopsies (<20,mg) of preinvasive and invasive cervical disease and to correlate the spectral profiles with sample classification on the basis of histopathology. Tissue samples were obtained at colposcopic examination, during local treatment of cervical intraepithelial neoplasia (CIN) or at hysterectomy. 1H MAS MRS was performed at 25°C while spinning the sample at 4.5,kHz. After measurement, the tissue was immersed in formalin and the pathology determined. Histological examination after 1H MAS MRS defined 27 samples with squamous cell carcinoma (SCC), 12 with CIN and 39 with only normal tissue. The standardized integrals of the lipid, choline and creatine regions of the spectra were significantly higher in SCC than in normal or CIN tissue. There was no obvious difference in the standardized integral of the region 4.15,3.5,ppm. The acyl fatty acid side-chain length was longer or less unsaturated in SCC than in normal tissue. Normal tissue from patients with SCC showed significantly higher triglycerides than normal tissue from patients with benign uterine disease but significantly lower triglycerides than SCC tissue. 1H MAS MRS of the uterine cervix ex vivo may be used to differentiate non-invasive from invasive cervical lesions, increase interpretation of in vivo MRS and provide insights into tumor biology. Copyright © 2004 John Wiley & Sons, Ltd. [source] Neural damage due to temporal lobe epilepsy: Dual-nuclei (proton and phosphorus) magnetic resonance spectroscopy studyPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 1 2004TAKAYUKI OBATA md Abstract, The aim of this study was to evaluate the usefulness of proton and phosphorus (1H and 31P) magnetic resonance spectroscopy (MRS) for temporal lobe epilepsy (TLE) patients, and to evaluate neural damage and metabolite dysfunction in the TLE patient brain. We performed 1H and 31P MRS of medial temporal lobes (MTL) in the same TLE patients (n = 14) with a relatively wide range of severity from almost seizure-free to intractable, and calculated the ratio of N-acetylasparate to choline-containing compounds and creatine + phosphocreatine (NAA/Cho + Cr) in 1H MRS and inorganic phosphate to all main peaks (%Pi) in 31P MRS. There was no significant correlation between NAA/(Cho + Cr) and %Pi ,in ,each ,side ,(ipsilateral, ,r = ,0.20; ,contralateral, ,r =,0.19). The values of NAA/(Cho + Cr) showed a significant difference between ipsilateral and contralateral MTLs to the focus of TLE patients (P < 0.01, paired t -test). Although %Pi also had a tendency to show the laterality of TLE, there was no significance. Ipsilateral (r = ,0.90, P < 0.0001) and contralateral (r = ,0.70, P < 0.005) NAA/(Cho + Cr) decreases and contralateral %Pi increase (r = 0.81, P < 0.001) had significant correlation with seizure frequency. 1H MRS provides more important information concerning neuronal dysfunction in MTL of TLE patients than 31P MRS. [source] Increased glutamate/glutamine compounds in the brains of patients with fibromyalgia: A magnetic resonance spectroscopy studyARTHRITIS & RHEUMATISM, Issue 6 2010Manuel Valdés Objective Fibromyalgia (FM) has been defined as a systemic disorder that is clinically characterized by pain, cognitive deficit, and the presence of associated psychopathology, all of which are suggestive of a primary brain dysfunction. This study was undertaken to identify the nature of this cerebral dysfunction by assessing the brain metabolite patterns in patients with FM through magnetic resonance spectroscopy (MRS) techniques. Methods A cohort of 28 female patients with FM and a control group of 24 healthy women of the same age were studied. MRS techniques were used to study brain metabolites in the amygdala, thalami, and prefrontal cortex of these women. Results In comparison with healthy controls, patients with FM showed higher levels of glutamate/glutamine (Glx) compounds (mean ± SD 11.9 ± 1.6 arbitrary units [AU] versus 13.4 ± 1.7 AU in controls and patients, respectively; t = 2.517, 35 df, corrected P = 0.03) and a higher Glx:creatine ratio (mean ± SD 2.1 ± 0.4 versus 2.4 ± 1.4, respectively; t = 2.373, 35 df, corrected P = 0.04) in the right amygdala. In FM patients with increased levels of pain intensity, greater fatigue, and more symptoms of depression, inositol levels in the right amygdala and right thalamus were significantly higher. Conclusion The distinctive metabolic features found in the right amygdala of patients with FM suggest the possible existence of a neural dysfunction in emotional processing. The results appear to extend previous findings regarding the dysfunction in pain processing observed in patients with FM. [source] Brain involvement in rheumatoid arthritis: A magnetic resonance spectroscopy studyARTHRITIS & RHEUMATISM, Issue 11 2009Bart J. Emmer Objective Tumor necrosis factor , was recently implicated as an important mediator of communication between the peripheral and cerebral immune systems in an animal model of chronic inflammation. The purpose of this study was to examine by proton magnetic resonance spectroscopy (1H-MRS) the influence of inflammation on cerebral metabolism in patients with rheumatoid arthritis (RA). Methods Single-voxel 1H-MRS of the centrum semiovale was performed on 35 RA patients (6 men and 29 women; mean ± SD age 51.8 ± 14.6 years) and 28 healthy age- and sex-matched control subjects (9 men and 19 women; mean ± SD age 50.2 ± 10.4 years). None of the study subjects had any neurologic signs or symptoms. Clinical markers of disease activity were correlated with the 1H-MRS findings. Results Patients with active RA, as reflected by an elevated erythrocyte sedimentation rate (ESR), had a significantly higher ratio of choline to creatine and a significantly lower ratio of N -acetylaspartate to choline than did patients with inactive RA, as reflected by a normal ESR. Moreover, the ratios of choline to creatine and NAA to choline were significantly correlated with the ESR after correction for age, sex, smoking status, handedness, alcohol consumption, medication use, and disease duration. Medication use had no additional effect on these associations. Conclusion Our data show that systemic inflammation in RA is associated with metabolic changes in the brain. [source] | ||||||||||