Applied Magnetic Resonance最新文献_第10页

Characterization of Hepatic Steatosis in Alcoholic (NIAAA) and Non-alcoholic Models (MCD and CCl4) via 9.4 T Magnetic Resonance Spectroscopy 9.4 T磁共振波谱法表征酒精（NIAAA）和非酒精模型（MCD和CCl4）肝脏脂肪变性

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-09-08 DOI: 10.1007/s00723-025-01799-4

Seung-Man Yu

{"title":"Characterization of Hepatic Steatosis in Alcoholic (NIAAA) and Non-alcoholic Models (MCD and CCl4) via 9.4 T Magnetic Resonance Spectroscopy","authors":"Seung-Man Yu","doi":"10.1007/s00723-025-01799-4","DOIUrl":"10.1007/s00723-025-01799-4","url":null,"abstract":"<div>The study aimed to compare lipid proton concentrations across three fatty liver models, highlighting induction methods and differences in hepatic protonation identified through magnetic resonance spectroscopy (MRS) analysis to gain insights into fatty liver pathogenesis and potential therapeutic approaches. This research sought to induce various conditions of fatty liver and examine disparities in hepatic protonation patterns through meticulous MRS analysis. The models for fatty liver in mice were established using distinct methods including ethanol feeding, MCD diet, and CCl4 injection. MRS was utilized for lipid proton analysis, with data processed using LCModel software. Statistical analyses encompassed profile comparisons via OPLS-DA, consistency evaluations using Kendal correlation, assessments of concentration differences via Mann–Whitney U test, and an exploration of lipid accumulation influences through Spearman's correlation analysis. All three fatty liver models displayed hepatic fat infiltration rates exceeding 40%, with the MCD model showing the highest rate at 52.46%. Analyzing the lipid protons, a higher concentration of methylene protons was observed in the NIAAA model compared to the other groups. Additionally, there were notable distinctions in the composition values of specific lipid protons across the models, highlighting varying trends in fatty acid deposition. The correlation and composition analysis provided insights into the different patterns of lipid accumulation in each model, with significant correlations identified among various lipid protons. Furthermore, differences in the composition values of specific lipid protons indicated distinct characteristics of fatty acid profiles in the different fatty liver models. No significant differences were found between the NIAAA and CCl4 models, but the MCD model exhibited higher deposition of polyunsaturated bonds, specifically diallylic protons, compared to other groups.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"56 12","pages":"1763 - 1777"},"PeriodicalIF":1.1,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145493516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Isotopic Dilution Provides No Evidence for Cu2+-Bridged β-Amyloid Homo-Oligomers 同位素稀释没有提供Cu2+桥接β-淀粉样蛋白同源低聚物的证据

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-09-08 DOI: 10.1007/s00723-025-01795-8

Simon C. Drew

{"title":"Isotopic Dilution Provides No Evidence for Cu2+-Bridged β-Amyloid Homo-Oligomers","authors":"Simon C. Drew","doi":"10.1007/s00723-025-01795-8","DOIUrl":"10.1007/s00723-025-01795-8","url":null,"abstract":"<div>The oligomerization of many peptides is known to be influenced by the binding of transition metal ions, with intermolecular metal–ion bridges being one possible mechanism. In the case of copper ions, it is possible to identify Cu2+ bridges between peptide monomers using EPR spectroscopy by analyzing the metal–ligand hyperfine structure in the spectra of a mixture of two peptides, each having the same amino acid sequence but a different isotopic content. This isotopic dilution method was previously used to show that the N-terminus of the misfolding peptide α-synuclein forms antiparallel Cu2+-bridged dimers, and such a quaternary structure was also proposed for the Cu2+-bound form of another misfolding peptide, β-amyloid (Aβ). To investigate this possibility, the isotopic dilution strategy was applied to the Aβ1–16 peptide, which contains the complete N-terminal Cu2+-binding domain of Aβ. Rigorous analysis of the superhyperfine structure in experimental and simulated low-frequency EPR spectra provided no conclusive evidence for Cu2+ bridging of Aβ monomers in the pH range 6.5–8.5.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"56 :","pages":"1423 - 1443"},"PeriodicalIF":1.1,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00723-025-01795-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Confirmation of the Spin Exchange Paradigm in Diluted Solution of Nitroxide Radical: Spin Polariton Formation 氮氧自由基稀释溶液中自旋交换范式的确认：自旋极化子的形成

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-09-05 DOI: 10.1007/s00723-025-01797-6

R. B. Zaripov, M. M. Bakirov, I. T. Khairutdinov, K. M. Salikhov

引用次数: 0

Optimizing Sludge Dewatering Efficiency Through Pore Size-Particle Size Matching: A Multimodal NMR and Machine Learning Approach 通过孔径-粒度匹配优化污泥脱水效率：多模态核磁共振和机器学习方法

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-08-26 DOI: 10.1007/s00723-025-01796-7

Yongzheng Qi, Chen Jin, Zhongyang Xu, Haoqing Xu, Tao Wu, Junhao Zhang

{"title":"Optimizing Sludge Dewatering Efficiency Through Pore Size-Particle Size Matching: A Multimodal NMR and Machine Learning Approach","authors":"Yongzheng Qi, Chen Jin, Zhongyang Xu, Haoqing Xu, Tao Wu, Junhao Zhang","doi":"10.1007/s00723-025-01796-7","DOIUrl":"10.1007/s00723-025-01796-7","url":null,"abstract":"<div>Sludge dewatering is a critical stage in sludge treatment, directly influencing the efficiency and environmental risks of subsequent disposal. This study systematically investigated the optimization of sludge dewatering by analyzing the matching relationship between the pore size of filter media materials and sludge particle size. The equivalent pore sizes of materials (e.g., nylon fabrics, geotextiles) were determined using nuclear magnetic resonance (NMR) and a machine learning-based image analysis method (IAM). Model experiments evaluated their dewatering performance. Results demonstrated that NMR, based on transverse relaxation time (T₂) inversion, achieved high accuracy for hydrophilic multilayer materials like geotextiles (errors < 11%), while IAM showed ± 10% error for hydrophobic single-layer materials (e.g., nylon fabrics) but up to 53.91% error for geotextiles due to complex fiber interweaving. Optimal dewatering was achieved when the filter media pore size (O95) matched the sludge’s volume-mean particle size (D[4,3]). The 400-g/m2 geotextile (pore size: 65 μm) exhibited the best alignment with the sludge’s D[4,3] (63.54 μm), yielding a relatively low cake moisture content and significantly reduced filtrate turbidity. This study provides a theoretical foundation for filter media selection and highlights the importance of pore size-particle size matching in enhancing dewatering efficiency, offering practical guidance for engineering applications.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"56 12","pages":"1741 - 1762"},"PeriodicalIF":1.1,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145493518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the Application of the New Spin Exchange Paradigm to Numerical Modeling of EPR Spectra 新自旋交换范式在EPR光谱数值模拟中的应用

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-08-25 DOI: 10.1007/s00723-025-01793-w

S. O. Travin, K. M. Salikhov

引用次数: 0

Why Does not Oxygen as an Oxidizer of Nitric Oxide Eliminate it from the Human and Animals' Organism? (The Role of EPR-Active Dinitosyl Iron Complexes with Thiol-Containing Ligands in the Preservation of Nitric Oxide in These Organisms) 为什么氧作为一氧化氮的氧化剂不能将其从人体和动物体内清除？（epr活性二硝基铁配合物与含硫醇配体在这些生物中保存一氧化氮的作用）

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-08-25 DOI: 10.1007/s00723-025-01772-1

Anatoly F. Vanin

{"title":"Why Does not Oxygen as an Oxidizer of Nitric Oxide Eliminate it from the Human and Animals' Organism? (The Role of EPR-Active Dinitosyl Iron Complexes with Thiol-Containing Ligands in the Preservation of Nitric Oxide in These Organisms)","authors":"Anatoly F. Vanin","doi":"10.1007/s00723-025-01772-1","DOIUrl":"10.1007/s00723-025-01772-1","url":null,"abstract":"<div>It has been shown that the preservation of nitric oxide (NO) in the tissues of animal and human organs, despite the presence of a significant amount (up to several millimoles) of oxygen (O2) as an oxidizer of NO, can be due to two reasons. The first, trivial one is determined by the low rate of NO oxidation by oxygen at its concentration of less than 10 μM, at which the remaining amount of NO is sufficient to implement its biological effect, for example, the ability to exert a vasodilatory effect on blood vessels. At NO concentrations of 50 μM or more, for example, in activated macrophages, an increase in the NO oxidation rate can sharply decrease the NO concentration in macrophages and thereby weaken their immune activity. In this case, NO oxidation is prevented by its inclusion in EPR-active dinitrosyl iron complexes (DNICs) with thiol-containing ligands. The formation of these complexes is determined by the competitive inclusion of a divalent weakly bound (\"free\") iron ion instead of an oxygen molecule into the dimeric form of NO, as a target for the oxidative action of oxygen on NO. The inclusion of NO in DNICs not only stabilizes NO, but also leads to the transformation of half of it in these complexes into nitrosonium cations (NO+). As a result, DNICs with thiol-containing ligands can act in the body of animals and humans not only as donors of NO molecules as positive regulators of various metabolic processes, but also as NO+ cations as negative, cytotoxic agents.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"56 12","pages":"1595 - 1608"},"PeriodicalIF":1.1,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145493513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spin Exchange Titration in Studying Spatial Organization of Polymer–Metal Coils in Liquid Solutions 自旋交换滴定法研究液体溶液中聚合物金属线圈的空间组织

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-08-24 DOI: 10.1007/s00723-025-01791-y

Alexander I. Kokorin

{"title":"Spin Exchange Titration in Studying Spatial Organization of Polymer–Metal Coils in Liquid Solutions","authors":"Alexander I. Kokorin","doi":"10.1007/s00723-025-01791-y","DOIUrl":"10.1007/s00723-025-01791-y","url":null,"abstract":"<div>Spin exchange interaction between nitroxide radicals (R) and transition metal ions such as Cu(II) and Zn(II) has been studied. In this work, basing on the results obtained on the analysis of [Polymer–Cu(II)–R] systems, we demonstrate peculiarities of small molecules diffusion inside such systems in aqueous solutions of complex-forming polymers: partially alkylated poly(4-vinylpyridine) (P4VP-β), poly(2-methyl-5-vinylpyridine) (P2M5VP-β), branched (BPEI) and linear (LPEI) poly(ethylenimine). The metal ion nature, concentration, spin–lattice relaxation time, the spin probe electric charge and size manifested significant effect on the collisions between Cu–polymer complexes and R. Correct selection of the radical (probe) makes possible obtaining reliable information on the structure of polymer–metal complexes in solutions and about the fraction of the functional groups of a macromolecule involved in the formation of complexes of various types. We believe that the spin-exchange titration (SET) approach will be useful for elucidation peculiarities of small molecules intercalation into ion-exchange resins, supported catalysts based on various nano- and micro-porous organic and inorganic carriers.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"56 :","pages":"1249 - 1255"},"PeriodicalIF":1.1,"publicationDate":"2025-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145296849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Applicability of NMR Spectroscopy in the Determination of Structures Containing a Fragment of Spiro[1-Azabicyclo[3.3.0]octane] 核磁共振波谱法测定含螺[1-阿扎比环[3.3.0]辛烷]片段结构的适用性

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-08-22 DOI: 10.1007/s00723-025-01780-1

Yulia A. Pronina, Alexander V. Stepakov, Ekaterina V. Berezhnaya, Vitali M. Boitsov, Ruslan I. Baichurin, Stanislav I. Selivanov

{"title":"The Applicability of NMR Spectroscopy in the Determination of Structures Containing a Fragment of Spiro[1-Azabicyclo[3.3.0]octane]","authors":"Yulia A. Pronina, Alexander V. Stepakov, Ekaterina V. Berezhnaya, Vitali M. Boitsov, Ruslan I. Baichurin, Stanislav I. Selivanov","doi":"10.1007/s00723-025-01780-1","DOIUrl":"10.1007/s00723-025-01780-1","url":null,"abstract":"<div>Structures of two new spiro-adducts synthesized on the basis of [3 + 2]-cycloaddition reaction of stable azomethine ylide with styrene and 2,3-dihydrofuran, respectively, were defined by NMR methods. Complete signal assignments in 1H spectra of both compounds were obtained on base analysis of COSY and NOESY experiments by determination of scalar networks in the first case and spatial interactions in the second one, respectively. The identification of aromatic proton signals of indan-1.3-dione fragment was made on base registration of long-range NOEs between them and aliphatic protons which are located at the distances up to 6 angstroms. These proton assignments were helpful for the identification of carbon signals in 13C NMR spectra of compounds under study which were performed by combination of HSQC and HMBC data. Thus, the results of the consistent use of homonuclear (COSY, NOESY) and heteronuclear (HSQC, HMBC) allowed us to make a complete and unambiguous NMR description of two new spiro-adducts and prove their belonging to one of the four synthetically possible regioisomers: (2'SR,7a'RS)-2'-phenyl-1',2',5',6',7',7a'-hexahydrospiro[indene-2,3'-pyrrolizine]-1,3-dione) and (3aSR,3bSR,8aSR)-2,3,3a,3b,4,5,6,8a-octahydrospiro[furo[3,2-a]pyrrolizine-8,2'-indene]-1',3'-dione). The possibility of the existence of the second regioisomer in solution in the form of a fast (in the NMR time-scale) conformational exchange associated with pseudo-rotation around the CH2–CH2 bond in the ethane fragment of the oxygen-containing five-membered ring was detected.</div>","PeriodicalId":469,"journal":{"name":"Applied Magnetic Resonance","volume":"56 8","pages":"937 - 953"},"PeriodicalIF":1.1,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144909876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accurate NMR Diffusion Measurements of Reacting Systems 反应系统的精确核磁共振扩散测量

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-08-18 DOI: 10.1007/s00723-025-01779-8

William S. Price

引用次数: 0

Possible Spin Gap Transition of ESR at the Magnetization Plateau of the Distorted Diamond Spin Chain 畸变金刚石自旋链磁化平台上ESR可能的自旋间隙跃迁

IF 1.1 4区物理与天体物理

Applied Magnetic Resonance Pub Date : 2025-08-15 DOI: 10.1007/s00723-025-01788-7

Tôru Sakai

引用次数: 0