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Mixture analysis is crucial in many areas of chemistry, and a wide variety of separation methods are in use. A common method for physical separation is high-performance liquid chromatography (HPLC), but resolution is a problem: chemically similar species coelute. An alternative approach is diffusion-ordered NMR spectroscopy (DOSY), in which the signals of mixture components are separated according to the diffusion coefficient. Again, separation is limited if species diffuse similarly or have overlap in their NMR spectra. Using the two techniques in combination can resolve both NMR spectra and the elution profiles of individual components, even where both techniques fail when used in isolation. Recording diffusion NMR data as a function of HPLC retention time gives a three-dimensional (3D) data set that can be analyzed using multiway statistical methods. PARAFAC analysis of diffusion NMR data measured from HPLC eluate for commercial "monoacetin" (a mixture of glycerol and its mono-, di-, and triacetates) yielded fully resolved and quantitative NMR spectra and elution profiles for all four components, whereas neither HPLC nor diffusion NMR applied independently was able to resolve the components.
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http://dx.doi.org/10.1021/acs.analchem.4c04418 | DOI Listing |
Curr Med Imaging
September 2025
Department of Pharmacy, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.
Unlabelled: Leptomeningeal metastasis (LM) is a severe complication of solid malignancies, including lung adenocarcinoma, characterized by poor prognosis and diagnostic challenges. This study assesses whether curvilinear peri-brainstem hyperintense signals on MRI are a characteristic feature of LM in lung adenocarcinoma patients.
Methods: This retrospective study analyzed data from multiple centers, encompassing lung adenocarcinoma patients with peri-brainstem curvilinear hyperintense signals on MRI between January 2016 and March 2022.
Front Immunol
September 2025
Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
Introduction: Anti-N-methyl-D-aspartate receptor (NMDA-R) encephalitis is a neuropsychiatric disorder with additional psychiatric features caused by NMDA-R immunoglobulin G (IgG) antibodies in cerebrospinal fluid (CSF). This report presents the follow-up of a patient in whom we assumed mild NMDA-R encephalitis in the first psychotic episode.
Case Study: A patient with a prior episode of an acute polymorphic psychotic syndrome relapsed five and a half years later following a severe COVID-19 infection.
Front Oncol
August 2025
Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
Background: Low-grade endometrial stromal sarcoma (LG-ESS) is a rare malignant tumor of the female reproductive system with atypical clinical symptoms and slow progression.
Case: A 44-year-old female with a history of intermittent severe dysmenorrhea, previous laparoscopic myomectomy, and uterine artery embolization (UAE) presented with rapidly enlarging pelvic masses. Imaging revealed uterine masses suggestive of leiomyomas, although an adnexal origin could not be excluded.
Front Med (Lausanne)
August 2025
School of Sport and Exercise Rehabilitation, Jinzhou Medical University, Liaoning, China.
Objective: This study aimed to describe the MRI features of lower limbs (thighs and calves) in patients with anti-NXP2 antibody positive myositis, and explore their relationship with clinical manifestations and prognosis.
Methods: Adult patients with anti-NXP2 antibody who underwent both thigh and calf MRI examinations simultaneously were enrolled between 2017 and 2023. The MRI features and medical records of patients were reviewed.
Rev Cardiovasc Med
August 2025
Division of Cardiology and Department of Internal Medicine, Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology, 430030 Wuhan, Hubei, China.
Background: The causal relationship between migraines and patent foramen ovale (PFO) remains controversial, and a major unresolved question is how to define migraines attributable to PFO. Thus, this study aimed to determine if brain lesions could be a potential indicator of PFO-related migraines.
Methods: Consecutive migraine patients from 2017 to 2019 who underwent transthoracic echocardiography or transcranial Doppler examination with an agitated saline contrast injection were assessed for right-to-left shunts.