The influence of proton diffusion on nuclear magnetic resonance (NMR) relaxation was investigated in the presence of horse spleen ferritin at 7 T. Binary mixtures of water and glycerol were used to control diffusion within the range of 0.6-2.0 × 10(-9)m(2)/s, which was confirmed by pulsed gradient techniques. The effect of chemical exchange by hydrolysis between water and glycerol on relaxation was characterized with Carr-Purcell-Meiboom-Gill (CPMG) dispersion experiments. The relaxation rate enhancement of the protons due to ferritin was found to be inversely proportional to the diffusion coefficient. The enhancement increased by a factor of 3.6 over the range of diffusion coefficients, while the hydroxyl proton concentration decreased by a factor of 1.3. This result is in disagreement with the proton exchange dephasing model, which is independent of diffusion but predicts an inverse dependence on the hydroxyl concentration. Our data indicate that the role of diffusion dominates and must be considered when relaxation rates are used to determine iron concentration in vivo.
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http://dx.doi.org/10.1016/j.jmr.2012.02.005 | DOI Listing |
Int J Emerg Med
January 2025
Emergency Department, Shanghai United Family Hospital, 699 Pingtang Road, Changning District, Shanghai, 200335, China.
Background: Adenomyosis, typically associated with heavy menstrual bleeding and pelvic pain, is rarely linked to neurological complications. This case presents a rare instance of ischemic stroke in a young patient with adenomyosis and vascular abnormalities, underscoring the role of anemia, hypercoagulability, and vascular factors as potential contributors to cerebral infarction.
Case Presentation: We describe a 41-year-old female with a history of adenomyosis who presented with right-sided hemianopia and dizziness following severe menstrual bleeding.
Sci China Life Sci
January 2025
Institute of Cardiovascular Sciences, School of Basic Medical Sciences, Peking University Health Science Center; Department of Cardiology and Institute of Vascular Medicine, Peking University Third Hospital; State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing, 100191, China.
Diffuse-type tenosynovial giant cell tumor (dTGCT) is a destructive but rare benign proliferative synovial neoplasm. Although surgery is currently the main treatment modality for dTGCT, the recurrence risk is up to 50%. Therefore, there is a great need for effective drugs against dTGCT with minor side effects.
View Article and Find Full Text PDFSci China Life Sci
January 2025
Nanhu Laboratory, National Center of Biomedical Analysis, Beijing, 100850, China.
The infiltration of glioblastoma multiforme (GBM) is predominantly characterized by diffuse spread, contributing significantly to therapy resistance and recurrence of GBM. In this study, we reveal that microtubule deacetylation, mediated through the downregulation of fibronectin type III and SPRY domain-containing 1 (FSD1), plays a pivotal role in promoting GBM diffuse infiltration. FSD1 directly interacts with histone deacetylase 6 (HDAC6) at its second catalytic domain, thereby impeding its deacetylase activity on α-tubulin and preventing microtubule deacetylation and depolymerization.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Fisicoquímica, X5000HUA Córdoba, Argentina.
Metallic lithium plays an important role in the development of next-generation lithium metal-based batteries. However, the uncontrolled growth of lithium dendrites limits the use of lithium metal as an anode. In this context, a stable solid electrolyte interphase (SEI) is crucial for regulating dendrite formation, stability, and cyclability of lithium metal anodes.
View Article and Find Full Text PDFHum Mol Genet
January 2025
Division of Neurology, Cincinnati Children's Hospital, 3333 Burnet Ave, Cincinnati, OH 45229, United States.
Myotonic Dystrophy type 2 (DM2) is a multisystem disease affecting many tissues, including skeletal muscle, heart, and brain. DM2 is caused by unstable expansion of CCTG repeats in an intron 1 of a gene coding for cellular nuclear binding protein (CNBP). The expanded CCTG repeats cause DM2 pathology due to the accumulation of RNA CCUG repeats, which affect RNA processing in patients' cells.
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