Muscular insulin resistance is frequently characterized by blunted increases in glucose-6-phosphate (G-6-P) reflecting impaired glucose transport/phosphorylation. These abnormalities likely relate to excessive intramyocellular lipids and mitochondrial dysfunction. We hypothesized that alterations action function should be present even nonobese patients with well-controlled type 2 diabetes mellitus (T2DM).We measured G-6-P, ATP synthetic flux (i.e., synthesis) lipid contents of skeletal...

OBJECTIVE Steatosis associates with insulin resistance and may even predict type 2 diabetes cardiovascular complications. Because muscular relates to myocellular fat deposition disturbed energy metabolism, we hypothesized that reduced hepatic ATP turnover (fATP) underlies elevated hepatocellular lipid (HCL) contents. RESEARCH DESIGN AND METHODS We measured fATP using 31P magnetic resonance spectroscopy in patients age- body mass–matched controls. Peripheral (M M/I) (suppression of endogenous...

Increased hepatocellular lipids relate to insulin resistance and are typical for individuals with type 2 diabetes mellitus (T2DM). Steatosis T2DM have been further associated impaired muscular adenosine triphosphate (ATP) turnover indicating reduced mitochondrial fitness. Thus, we tested the hypothesis that hepatic energy metabolism could be even in metabolically well-controlled T2DM. We measured lipid volume fraction (HLVF) absolute concentrations of gammaATP, inorganic phosphate (Pi),...

Purpose To qualitatively and quantitatively compare the diagnostic value of diffusion-weighted (DW) magnetic resonance (MR) imaging based on standard single-shot echo-planar readout-segmented in patients with breast cancer at 3.0 T. Materials Methods Institutional review board approval written informed consent were obtained. Forty-seven 49 histopathologically verified lesions included this study. In all patients, DW imaging, comparable parameters, was performed a 3.0-T MR imager. Two...

Abstract Phosphorus ( 31 P) T 1 and 2 relaxation times in the resting human calf muscle were assessed by interleaved, surface coil localized inversion recovery frequency‐selective spin‐echo at 3 7 T. The obtained (mean ± SD) decreased significantly P < 0.05) from to for phosphomonoesters (PME) (8.1 1.7 s 3.1 0.9 s), phosphodiesters (PDE) (8.6 1.2 6.0 1.1 phosphocreatine (PCr) (6.7 0.4 4.0 0.2 γ‐NTP (nucleotide triphosphate) (5.5 3.3 α‐NTP (3.4 0.3 1.8 0.1 β‐NTP (3.9 but not inorganic...

This work describes a new approach for high-spatial-resolution (1)H MRSI of the human brain at 7 T. T using conventional approaches, such as point-resolved spectroscopy and stimulated echo acquisition mode with volume head coils, is limited by technical difficulties, including chemical shift displacement errors, B(0)/B(1) inhomogeneities, high specific absorption rate decreased T(2) relaxation times. The method presented here based on free induction decay an ultrashort delay (TE*) 1.3 ms....

Long echo time (TE) MR spectroscopy (MRS) sequences are sensitive only to metabolites of low molecular weight. At shorter TE, significantly more metabolite signals detectable, including broad high-molecular-weight macromolecules (MMs). Although the presence MM resonances can bias quantification at short proper MMs is important since themselves may serve as potentially valuable biomarkers for many pathologies. We have therefore developed an FID-based 2D-MR Spectroscopic Imaging (2D-MRSI)...

Purpose To evaluate the diagnostic accuracy of quantitative, three-dimensional (3D) magnetic resonance (MR) spectroscopic imaging at 3 T for differentiation benign and malignant breast lesions, on basis choline (Cho) signal-to-noise ratio (SNR) threshold levels, in a clinically feasible measurement time. Materials Methods Institutional review board approval written informed consent were obtained from all subjects. Fifty female patients (mean age, 50 years; age range, 25–82 years) with...

Determinants of fatty liver (FL) might be predictive for further deterioration in insulin resistance (IR) women with previous gestational diabetes (pGDM). The aim was to evaluate the association between pGDM, FL and future manifestation type 2 (T2DM) by a detailed pathophysiological characterization early after pregnancy.68 pGDM 29 healthy controls were included 3-6 months delivery underwent specific metabolic assessments: status IR determined via oral- intravenous-glucose-tolerance-tests...

Purpose To compare a new parallel imaging (PI) method for multislice proton magnetic resonance spectroscopic (1H-MRSI), termed (2 + 1)D-CAIPIRINHA, with two standard PI methods: 2D-GRAPPA and 2D-CAIPIRINHA at 7 Tesla (T). Methods 1)D-CAIPIRINHA is combination of slice-CAIPIRINHA. Eight healthy volunteers were measured on 7T MR scanner using 32-channel head coil. The best undersampling patterns estimated all three methods. artifact powers, g-factors, Cramér–Rao lower bounds (CRLB), root mean...

OBJECTIVE We tested the hypothesis that short-term exercise training improves hereditary insulin resistance by stimulating ATP synthesis and investigated associations with gene polymorphisms. RESEARCH DESIGN AND METHODS studied 24 nonobese first-degree relatives of type 2 diabetic patients 12 control subjects at rest 48 h after three bouts exercise. In addition to measurements oxygen uptake sensitivity (oral glucose tolerance test), ectopic lipids mitochondrial were assessed using1H and31P...

The liver plays a central role in intermediate metabolism. Accumulation of fat (steatosis) predisposes to various diseases. Steatosis and abnormal muscle energy metabolism are found insulin-resistant type-2 diabetic states. To examine hepatic metabolism, we measured hepatocellular lipid content, using proton MRS, rates ATP synthesis vivo, the 31P magnetization transfer experiment. A suitable localization scheme was developed applied measurements longitudinal relaxation times (T1) six healthy...

This work presents a new approach for high‐resolution MRSI of the brain at 7 T in clinically feasible measurement times. Two major problems are long scan times large matrix sizes and possible spectral contamination by transcranial lipid signal. We propose combination free induction decay (FID)‐MRSI with short acquisition delay acceleration via in‐plane two‐dimensional generalised autocalibrating partially parallel (2D‐GRAPPA) adiabatic double inversion recovery (IR)‐based suppression to...

The goal of this study was to evaluate a new method combining multi‐channel 1 H MRSI data by direct use matching imaging scan as reference, rather than computing sensitivity maps. Seven healthy volunteers were measured on 7‐T MR scanner using head coil with 32‐channel array for receive‐only and volume receive/transmit. accuracy prediction the phase fast pre‐scan investigated coil. combined combination weights. signal‐to‐noise ratio (SNR), spectral quality, metabolic map quality Cramér–Rao...

Phosphorus MRSI (31 P-MRSI) using a spiral-trajectory readout at 7 T was developed for high temporal resolution mapping of the mitochondrial capacity exercising human skeletal muscle. The sensitivity and localization accuracy method investigated in phantoms. In vivo performance assessed 12 volunteers, who performed plantar flexion exercise inside whole-body MR scanner an MR-compatible ergometer surface coil. five volunteers knee flexed (~60°) to shift major workload from gastrocnemii soleus...

in type 2 diabetic patients and their first-degree relatives, insulin resistance (IR) is associated with impairment of insulin-stimulated myocellular glucose-6-phosphate (g6p) unidirectional flux through ATP synthase (fATP), suggesting the presence inherited abnormal mitochondrial oxidative fitness. We hypothesized that long-standing 1 diabetes may also exhibit as well lower fATP.this single-centre trial was registered at ClinicalTrials.gov (NCT00481598).we included eight nonobese (mean...

Abstract Liver dysfunction correlates with alterations of intracellular concentrations 31 P metabolites. Localization and absolute quantification should help to trace regional hepatic metabolism. An improved protocol for the metabolites in vivo human liver was developed by employing three‐dimensional (3D) k ‐space weighted spectroscopic imaging (MRSI) B 1 ‐insensitive adiabatic excitation. The allowed high spatial resolution 17.8 ± 0.22 cm 3 34 min at T. No pulse adjustment prior MRSI...

Ectopic lipid storage in muscle (intramyocellular lipids [IMCL]) and liver (hepatocellular [HCL]) coexists with impaired myocellular flux through ATP synthase (fATPase) certain cohorts increased risk of type 2 diabetes. Because women a history gestational diabetes mellitus (pGDM) have elevated ectopic risk, we tested whether deteriorated energy metabolism contributes to these abnormalities.A total 23 glucose-tolerant nonobese pGDM eight normal glucose during pregnancy similar age, body mass,...

Abstract An improved image selected in vivo spectroscopy (ISIS) sequence for localized 31 P magnetic resonance at 7 T was developed. To reduce errors localization accuracy, adiabatic excitation, gradient offset independent inversion pulses, and a special extended ISIS ordering scheme were used. The accuracy of investigated phantoms. possible spectral quality reproducibility explored volunteer (brain, muscle, liver). A comparison between 3 performed five volunteers. Adiabatic provided high...

Phosphorus ( 31 P) MRS is a powerful tool for the non‐invasive investigation of human liver metabolism. Four in vivo P localization approaches (single voxel image selected spectroscopy (3D‐ISIS), slab selective 1D‐ISIS, 2D chemical shift imaging (CSI), and 3D‐CSI) with different volumes acquisition times were demonstrated nine healthy volunteers. Localization techniques provided comparable signal‐to‐noise ratios normalized volume time differences, Cramer–Rao lower bounds (8.7 ± 3.3% 1D‐ISIS...