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51.
Metabolic imaging of atrophic muscle tissue using appropriate markers in 1H and 31P NMR spectroscopy
Introduction The purpose of this feasibility study was to demonstrate non-invasive metabolic imaging of human muscular atrophy using significant changes of NMR signals that are related directly or indirectly to fiber necrosis.Methods Single-voxel 1H NMR spectroscopy and two-dimensional 31P spectroscopic imaging on a 1.5-T whole-body scanner were used for in vivo mapping of areas of muscle damage in two cases of differently localized and pronounced atrophy. Spectral patterns affiliated with severe and intermediate stages of degeneration were compared to data of healthy control tissue to derive appropriate metabolic markers related to lipid infiltration or high-energy 31P metabolism.Results Reliable detection of atrophic tissue was achieved by the following parameters: (1) liposclerotic turnover is related to a drastic reduction in the water/lipid 1H signal intensity ratio (up to a factor of 74 compared to adjacent healthy tissue); (2) the 31P resonance of phosphocreatine (PCr) is an adequate marker for differentiation of intact myocells with high-energy metabolism from regions dominated by terminal fiber necrosis (PCr signal vanished nearly completely or intensity was reduced by a factor of 3 in affected muscles). Metabolic images based on this signal allowed accurate non-invasive localization of atrophic tissue.Conclusion The molecular information provided by NMR spectroscopy—previously only used with poor localization in atrophy studies—enables access to both the myocell-specific high-energy metabolism and the result of lipid infiltration allowing non-invasive mapping of degenerate tissue. The ability to investigate the results of these advanced levels of atrophy would also be useful for studies of more subtle degrees of denervation. 相似文献
52.
Dynamic Contrast‐Enhanced Sonography and Dynamic Contrast‐Enhanced Magnetic Resonance Imaging for Preoperative Diagnosis of Infected Nonunions 下载免费PDF全文
53.
Emmanuel Jouglar Vanina Isnardi Dorothée Goulon Céline Ségura-Ferlay Myriam Ayadi Claire Dupuy Jean-Yves Douillard Marc-André Mahé Line Claude 《Radiotherapy and oncology》2018,126(2):291-299
Purpose
To determine the patterns of locoregional failure (LRF) in patients with locally advanced non-small cell lung cancer treated with definitive radiotherapy (RT).Patients and methods
One hundred and fifty-four patients from the Gating 2006 prospective randomized trial were treated with conformal RT with or without respiratory motion management. For patients with a LRF as first event, treatment planning with simulation CT, pre-treatment 18FDG PET-CT and post-treatment images demonstrating recurrence were registered and analyzed. Measurable LRF was contoured (rGTV) and classified as in-field, marginal, or out-of-field.Results
Median follow-up was 27.8?months. Forty-eight patients presented with LRF. One-year and 2-year locoregional disease-free survival rates were 77% (95% CI 70–83) and 72% (95% CI 64–79) respectively. 79% of the patients with LRF as first event relapsed within the RT field (55% isolated), 30% had marginal LRF component. Isolated out-of-field failure occurred in only 3% of all patients. The regions of highest FDG-uptake on pre-treatment PET-CT were located within the recurrence in 91% of patients with in-field LRF.Conclusion
In-field failure was the most common pattern of failure. Escalated dose RT with high-dose fractions guided by PET parameters warrants further investigation. 相似文献54.
55.
56.
Kirsi Harju Marja-Leena Rapinoja Marc-André Avondet Werner Arnold Martin Sch?r Stephen Burrell Werner Luginbühl Paula Vanninen 《Toxins》2015,7(12):4868-4880
Saxitoxin (STX) and some selected paralytic shellfish poisoning (PSP) analogues in mussel samples were identified and quantified with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Sample extraction and purification methods of mussel sample were optimized for LC-MS/MS analysis. The developed method was applied to the analysis of the homogenized mussel samples in the proficiency test (PT) within the EQuATox project (Establishment of Quality Assurance for the Detection of Biological Toxins of Potential Bioterrorism Risk). Ten laboratories from eight countries participated in the STX PT. Identification of PSP toxins in naturally contaminated mussel samples was performed by comparison of product ion spectra and retention times with those of reference standards. The quantitative results were obtained with LC-MS/MS by spiking reference standards in toxic mussel extracts. The results were within the z-score of ±1 when compared to the results measured with the official AOAC (Association of Official Analytical Chemists) method 2005.06, pre-column oxidation high-performance liquid chromatography with fluorescence detection (HPLC-FLD). 相似文献
57.
58.
Weber MA Jappe U Essig M Krix M Ittrich C Huttner HB Huttner BH Meyding-Lamadé U Hartmann M Kauczor HU Delorme S 《Journal of neurology》2006,253(12):1625-1632
Objective To evaluate prospectively contrast-enhanced ultrasound (CEUS) in patients suspected of having dermatomyositis or polymyositis.
Methods In 35 patients (23 women, 12 men; mean age, 51 years ± 16 years) who were suspected of having dermatomyositis or polymyositis,
perfusion in clinically affected skeletal muscles was quantified with contrast-enhanced intermittent power Doppler ultrasound.
By applying a modified model that analyzed the replenishment kinetics of microbubbles, the perfusion-related parameters blood
flow, local blood volume and blood flow velocity were measured. Findings were compared with muscle biopsy appearances and
with the results of MRI that was performed with a 1.5-Tesla unit. Receiver operating characteristic analysis was performed
and optimum thresholds for diagnosis of myositis were determined.
Results Eleven patients had histologically confirmed dermatomyositis or polymyositis and showed significantly higher blood flow velocity
(P = .01 for dermato- and P < .001 for polymyositis), blood flow (P < .001 for dermato- and polymyositis), and blood volume (P = .007 for dermato- and P < .001 for polymyositis) on contrast-enhanced ultrasound than those who did not have myositis. An increase in signal intensity
on T2-weighted MR images was found in all patients with myositis. MRI had a sensitivity, specificity, positive (PPV), and
negative predicting values (NPV) of 100%, 88%, 77%, and 100% for diagnosis of myositis, respectively. CEUS blood flow was
the best ultrasound measure for diagnosis of dermato- or polymyositis with sensitivity, specificity, PPV, and NPV of 73%,
91%, 80%, and 88%, respectively.
Conclusions Increased skeletal muscle perfusion measured by CEUS could serve as an additional measurer for the diagnosis of an inflammatory
myopathy.
Received in revised form: 6 June 2006
An erratum to this article is available at . 相似文献
59.
Marc-André Verner Anne E. Loccisano Nils-Halvdan Morken Miyoung Yoon Huali Wu Robin McDougall Mildred Maisonet Michele Marcus Reiko Kishi Chihiro Miyashita Mei-Huei Chen Wu-Shiun Hsieh Melvin E. Andersen Harvey J. Clewell III Matthew P. Longnecker 《Environmental health perspectives》2015,123(12):1317-1324
Background
Prenatal exposure to perfluoroalkyl substances (PFAS) has been associated with lower birth weight in epidemiologic studies. This association could be attributable to glomerular filtration rate (GFR), which is related to PFAS concentration and birth weight.Objectives
We used a physiologically based pharmacokinetic (PBPK) model of pregnancy to assess how much of the PFAS–birth weight association observed in epidemiologic studies might be attributable to GFR.Methods
We modified a PBPK model to reflect the association of GFR with birth weight (estimated from three studies of GFR and birth weight) and used it to simulate PFAS concentrations in maternal and cord plasma. The model was run 250,000 times, with variation in parameters, to simulate a population. Simulated data were analyzed to evaluate the association between PFAS levels and birth weight due to GFR. We compared simulated estimates with those from a meta-analysis of epidemiologic data.Results
The reduction in birth weight for each 1-ng/mL increase in simulated cord plasma for perfluorooctane sulfonate (PFOS) was 2.72 g (95% CI: –3.40, –2.04), and for perfluorooctanoic acid (PFOA) was 7.13 g (95% CI: –8.46, –5.80); results based on maternal plasma at term were similar. Results were sensitive to variations in PFAS level distributions and the strength of the GFR–birth weight association. In comparison, our meta-analysis of epidemiologic studies suggested that each 1-ng/mL increase in prenatal PFOS and PFOA levels was associated with 5.00 g (95% CI: –21.66, –7.78) and 14.72 g (95% CI: –8.92, –1.09) reductions in birth weight, respectively.Conclusion
Results of our simulations suggest that a substantial proportion of the association between prenatal PFAS and birth weight may be attributable to confounding by GFR and that confounding by GFR may be more important in studies with sample collection later in pregnancy.Citation
Verner MA, Loccisano AE, Morken NH, Yoon M, Wu H, McDougall R, Maisonet M, Marcus M, Kishi R, Miyashita C, Chen MH, Hsieh WS, Andersen ME, Clewell HJ III, Longnecker MP. 2015. Associations of perfluoroalkyl substances (PFAS) with lower birth weight: an evaluation of potential confounding by glomerular filtration rate using a physiologically based pharmacokinetic model (PBPK). Environ Health Perspect 123:1317–1324; http://dx.doi.org/10.1289/ehp.1408837 相似文献60.
Marc-André Verner Jaime E. Hart Sharon K. Sagiv David C. Bellinger Larisa M. Altshul Susan A. Korrick 《Environmental health perspectives》2015,123(9):888-894