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Controlled radio-frequency hyperthermia using an MR scanner and simultaneous monitoring of temperature and therapy response by (1)H, (23)Na and (31)P magnetic resonance spectroscopy in subcutaneously implanted 9L-gliosarcoma.

A magnetic resonance (MR) technique is developed to produce controlled radio-frequency (RF) hyperthermia (HT) in subcutaneously-implanted 9L-gliosarcoma in Fisher rats using an MR scanner and its components; the scanner is also simultaneously used to monitor the tumour temperature and the metabolic response of the tumour to the therapy. The method uses the (1)H chemical shift of thulium 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetra-acetic acid (TmDOTA(-)) to monitor temperature. The desired HT temperature is achieved and maintained using a feedback loop mechanism that uses a proportional-integ

In vivo mapping of postprandial hepatic glucose metabolism using dynamic magnetic resonance spectroscopy combined with stable isotope flux analysis in Roux-en-Y gastric bypass adults and non-operated controls: A case-control study.

AIMS: Roux-en-Y gastric bypass (RYGB) surgery alters postprandial glucose profiles, causing post-bariatric hypoglycaemia (PBH) in some individuals. Due to the liver's central role in glucose homeostasis, hepatic glucose handling might differ in RYGB-operated patients with PBH compared to non-operated healthy controls (HC). MATERIALS AND METHODS: We enrolled RYGB-operated adults with PBH and HCs (n = 10 each). Participants ingested 60 g of [6,6'-2H2]-glucose (d-glucose) after an overnight fast. Deuterium metabolic imaging (DMI) with interleaved 13C magnetic resonance spectroscopy was performed…

Magnetic Resonance Spectroscopy Lipids Peak May Serve as a Potential Biomarker for Back Pain in Intervertebral Disc Degeneration: An Integrative Metabolomics and Proteomics Study Investigating the Role of the Lipid Droplets-Interleukin-17 Inflammatory Axis.

OBJECTIVE: To explore and validate clinical magnetic resonance spectroscopy (MRS) biomarkers associated with patient-reported symptoms in intervertebral disc degeneration, and to further elucidate the pathogenic mechanisms linking these symptoms to MRS biomarkers via an integrative multiomics approach. METHODS: Patients categorized into the predominant lipids peak (pLP) group and the non-pLP group based on MRS spectrum lipids peak. Nucleus pulposus cells underwent lipidomics, proteomics and functional experiments. Outcome measures compared, and Pearson correlation coefficient evaluated relati…

Дигит Спан тесты более чувствительны, чем SDMT для обнаружения рабочего нарушения памяти и корреляции с метаболическими изменениями в белой материи и глубоко серой материи Nucley в многоразовом склерозе: исследование GABA-Edited Magnetic Resonance Spectropy.

В этом документе мы ставили цель оценить эффективность и полезность трех кратких, легко управляемых и повторяемых тестов, а именно: SDMT, Digit Span Forth (DSF) и Digit Span Backward (DSB) в случае пациентов с MS (MSp), и сравнить результаты с результатами здоровых добровольцев (CON). Мы надеялись определить наиболее чувствительный тест, который мог бы регулярно использоваться в клинической практике. Кроме того, мы попытались определить метаболический фон когнитивной настройки с использованием усовершенствованного радиологического метода Mescher-Garwood (MEGA) с использованием 1H магнитной спе

Совпадение в аннотации оригинала
In this paper, we aimed to evaluate the efficacy and usefulness of three brief, easy-to-administer, and repeatable tests, namely SDMT, Digit … d of the cognitive setting using the advanced radiological method, Mescher-Garwood (MEGA)-edited 1H Magnetic Resonance Spectroscopy (1H-MRS). A total of 22 relapsing MSp and 22 CONs were enrolled. The SDMT, DSF, and DSB tests were used on all participants. The patients also underwent a 1H-MRS brain examination. In addition to N-Acetyl-Aspartate (tNAA), Myoinositol (mIns), Cholin …

Comparison of the prognostic value of early-phase proton magnetic resonance spectroscopy and diffusion tensor imaging with serum neuron-specific enolase at 72 h in comatose survivors of out-of-hospital cardiac arrest-a substudy of the XeHypotheca trial.

PURPOSE: We compared the predictive accuracy of early-phase brain diffusion tensor imaging (DTI), proton magnetic resonance spectroscopy (1H-MRS), and serum neuron-specific enolase (NSE) against the motor score and epileptic seizures (ES) for poor neurological outcome after out-of-hospital cardiac arrest (OHCA). METHODS: The predictive accuracy of DTI, 1H-MRS, and NSE along with motor score at 72 h and ES for the poor neurological outcome (modified Rankin Scale, mRS, 3 - 6) in 92 comatose OHCA patients at 6 months was assessed by area under the receiver operating characteristic curve (AUROC).…

Adjunctive High-Definition Transcranial Direct Current Stimulation in Brain Glutamate-Glutamine and γ-Aminobutyric Acid, Withdrawal and Craving During Early Abstinence Among Patients With Opioid Use Disorder on Buprenorphine-Naloxone: A Proton Magnetic Resonance Spectroscopy-Based Pilot Study.

OBJECTIVE: Our study aimed to (1) examine the effect of adjunctive high-definition transcranial direct current stimulation (HD-tDCS) in crav … e Obsessive-Compulsive Drug Use Scale (OCDUS), and glutamate-glutamine and GABA at DLPFC via proton magnetic resonance spectroscopy were measured at baseline and on day 7. RESULTS: Both active and sham groups had comparable changes in DDQ, OCDUS (except 2 subcomponents), COWS, and glutamate-glutamine and GABA at DLPFC. In the active HD-tDCS group, statistically significant redu …

Structural elucidation of two novel degradants of lurasidone and their formation mechanisms under free radical-mediated oxidative and photolytic conditions via liquid chromatography-photodiode array/ultraviolet-tandem mass spectrometry and one-dimensional/two-dimensional nuclear magnetic resonance spectroscopy.

Lurasidone is an antipsychotic drug clinically used for the treatment of schizophrenia and bipolar disorder. During a mechanism-based forced degradation study of lurasidone, two novel degradation products were observed under free radical-mediated oxidative (via AIBN) and solution photolytic conditions. The structures of the two novel degradants were identified through an approach combining HPLC, LC-MSn (n = 1, 2), preparative HPLC purification and NMR spectroscopy. The degradant formed under the free radical-mediated condition is an oxidative degradant with half of the piperazine ring cleaved

Infantile Sandhoff's disease: multivoxel magnetic resonance spectrosecopy findings.

Sandhoff's disease is a rare, genetic lysosomal storage disease leading to delayed myelination or demyelination. Although neuroimaging findings in this disease have been reported previously, magnetic resonance spectroscopy findings have not been reported. In this report, we present magnetic resonance imaging and magnetic resonance spectrscopy features of two cases with Sandhoff's disease. Magnetic resonance spectroscopy revealed findings indicating widespread demyelination in both cases and neuroaxonal loss and anaerobic metabolism in the second case. Magnetic resonance spectroscopy could prov…

Phosphorus 31 nuclear magnetic resonance examination of female reproductive tissues.

Nuclear magnetic resonance spectroscopy is a powerful method of investigating the relationship between metabolism and function in living tissues. We present evidence that the phosphorus 31 spectra of myometrium and placenta are functions of physiologic state and gestational age. Specific spectroscopic abnormalities are observed in association with disorders of pregnancy and gynecologic diseases. Our results suggest that noninvasive nuclear magnetic resonance spectroscopy examinations may sometimes be a useful addition to magnetic resonance imaging examinations, and that nuclear magnetic resona…

Preclinical development and current status of the fluorinated 2-nitroimidazole hypoxia probe N-(2-hydroxy-3,3,3-trifluoropropyl)-2-(2-nitro-1-imidazolyl) acetamide (SR 4554, CRC 94/17): a non-invasive diagnostic probe for the measurement of tumor hypoxia by magnetic resonance spectroscopy and imaging, and by positron emission tomography.

Hypoxia occurs to a variable extent in a vast majority of rodent and human solid tumors. It results from an inadequate and disorganized tumo … de (SR 4554, CRC 94/17), which has been rationally designed for the measurement of tumor hypoxia by magnetic resonance spectroscopy (MRS) and imaging (MRI), are reviewed. Application in positron emission tomography (PET) detection is also proposed. Design goals were: (i) a nitro group with appropriate redox potential for selective reduction and binding in hypoxic tumor cells; (i …

Structure Confirmation of Three New Psychoactive Substances and Qualitative Identification of Unknown Substances.

OBJECTIVES: To establish the structural confirmation methods of three suspected new psychoactive substances (NPSs), and explore a more general qualitative testing method. METHODS: Infrared absorption spectroscopy (IR), gas chromatography-mass spectrometry (GC-MS), 1H-nuclear magnetic resonance spectroscopy (1H-NMR), 13C-nuclear magnetic resonance spectroscopy (13C-NMR), 19F-nuclear magnetic resonance spectroscopy (19F-NMR) and other techniques were used to identify the composition and structure of 5 samples containing suspected NPS submitted by public security bureaus. RESULTS: NPSs were fou…

Prenatal diagnosis of pyruvate dehydrogenase deficiency using magnetic resonance imaging.

INTRODUCTION: Pyruvate dehydrogenase deficiency is an inherited inborn error of metabolism associated with early neonatal death and long-term neurologic sequelae in survivors. Prenatal diagnosis currently relies on isolation of fetal cells for subsequent genetic and/or biochemical studies. Magnetic resonance imaging and magnetic resonance spectroscopy have been used on occasion for both postnatal diagnosis and management of pyruvate dehydrogenase deficiency. We illustrate a case in which these non-invasive modalities also prove useful for prenatal diagnosis of this condition. CASE: A 31-year-…

Intracerebral blood and MRS in neonatal nonketotic hyperglycinemia.

Nonketotic hyperglycinemia is an inborn error of glycine metabolism leading to the accumulation of glycine in the brain. The neonatal form p … cerebrospinal fluid-to-plasma-glycine ratio. An elevated glycine peak, using long echo time proton magnetic resonance spectroscopy, is also specific to nonketotic hyperglycinemia. The presence of blood in a cerebrospinal fluid sample is known to render the glycine level uninterpretable. However, there have been no reports of intracerebral blood confounding the cerebral glycine …

In vivo MR spectroscopy in diagnosis and research of neuropsychiatric disorders.

Magnetic resonance spectroscopy is one of the most important tools for quantitative analysis of chemical composition and structure, and this non-invasive technique is now being applied in vivo to study biochemical processes in those neuropsychiatric disorders that are part of the phospholipid spectrum. Interpretation of a clinical magnetic resonance spectrum can provide information about membrane phospholipid turnover, cellular energetics, neuronal function, selected neurotransmitter activity and intracellular pH. Cerebral proton and phosphorus magnetic resonance spectroscopy findings are summ…

MR spectroscopy and imaging in metabolic myopathies.

Magnetic resonance spectroscopy and imaging of muscle and brain offers new possibilities for noninvasive diagnosis of metabolic myopathies. These functional techniques allow assessment of the pathophysiology of these disorders and also can be used for monitoring disease evolution and response to therapy. In this article, the authors review the magnetic resonance spectroscopy and imaging features of mitochondrial encephalomyopathies, glycolytic disorders, and hypothyroidism.

The Dissolution-Dynamic Nuclear Polarization Experiment.

Dissolution-Dynamic Nuclear Polarization (D-DNP) addresses the most pressing issue of nuclear magnetic resonance spectroscopy - low sensitivity. In D-DNP the analyte is mixed with a radical in a glass-forming matrix. This substrate is frozen and kept at low temperature (<100 K) and a magnetic field of several Tesla. By using microwave irradiation, polarization is transferred from electron spins to nuclear spins. The substrate is then liquefied, and the liquid-state signal of the nuclear spins is observed in a high-resolution nuclear magnetic resonance (NMR) magnet or a magnetic resonance imagi…

Magnetic resonance biomarkers of neuroprotective effects in infants with hypoxic ischemic encephalopathy.

Evaluation of infants with hypoxic ischemic encephalopathy by magnetic resonance spectroscopy and imaging is useful to direct clinical care, and may assist the evaluation of candidate neuroprotective therapies. Cerebral metabolites measured by magnetic resonance spectroscopy, and visual analysis of magnetic resonance images during the first 30 days after birth accurately predict later neurological outcome and are valid biomarkers of the key physiological processes underlying brain injury in neonatal hypoxic ischemic encephalopathy. Visual assessment of magnetic resonance images may also be a s…

Cerebral mucormycosis: proton MR spectroscopy and MR imaging.

Proton magnetic resonance spectroscopy (MRS) was integrated with magnetic resonance imaging (MRI) in the evaluation of a case of cerebral mucormycosis. MRS showed markedly elevated lactate, depleted N-acetyl aspartate and metabolite resonances attributable to succinate and acetate. The spectroscopy profile is essentially similar to that of bacterial abscess but without the commonly seen resonances of the amino acids valine, leucine and isoleucine. Our extensive literature review did not yield any reports of MRS findings on cerebral mucormycosis. MRS prospectively limited the differential diagn…

Focal brain lactate accumulation in metformin-induced encephalopathy without systemic lactic acidosis: A case report suggesting mitochondrial vulnerability in lentiform fork sign.

Metformin causes metabolic encephalopathy in some patients with end-stage chronic kidney disease, resulting in impaired consciousness and parkinsonism. This encephalopathy has a very characteristic magnetic resonance imaging feature in lentiform nuclei known as the "lentiform fork sign". However, the mechanism is unknown. Here, we report a case of metformin-induced encephalopathy with a novel observation of lactate accumulation in the lentiform nuclei on magnetic resonance spectroscopy without systemic lactic acidosis. Since metformin is an inhibitor of mitochondrial complex-I, this focal brai…