The complete macro- and microequilibrium analyses of 3-nitrotyrosine, a biomarker of oxidative stress damage, are presented for the first time. The protonation macroconstants were determined by H-NMR-pH titration, while microconstants were elucidated by a combination of deductive and NMR methods, in which properties of the methyl ester derivative as an auxiliary compound were also studied. Combination of the NMR-pH characterization of the title and auxiliary compounds and the pair-interactivity parameters of 3-iodotyrosine provided the sufficient system to evaluate all the microconstants. NMR-pH profiles, macroscopic and microscopic protonation schemes, and species-specific distribution diagrams are included. The phenolate basicity of 3-nitrotyrosine is 500 times below that of tyrosine, and it is even lower than that of 3-iodotyrosine. This phenomenon can be explained by the stronger electron withdrawing and the negative mesomeric effect of the nitro group. Based on our results, 89 % of the phenolic OH groups are deprotonated in 3-NT molecules at the pH of the blood plasma.
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http://dx.doi.org/10.1002/cbdv.201900358 | DOI Listing |
Nat Commun
January 2025
School of Materials Science and Engineering, Peking University, Beijing, P.R. China.
Designing catalysts with well-defined, identical sites that achieve site-specific selectivity, and activity remains a significant challenge. In this work, we introduce a design principle of topological-single-atom catalysts (T-SACs) guided by density functional theory (DFT) and Ab initio molecular dynamics (AIMD) calculations, where metal single atoms are arranged in asymmetric configurations that electronic shield topologically misorients d orbitals, minimizing unwanted interactions between reactants and the support surface. Mn/CeO catalysts, synthesized via a charge-transfer-driven approach, demonstrate superior catalytic activity and selectivity for NO removal.
View Article and Find Full Text PDFJ Allergy Clin Immunol
January 2025
The National Allergy Research Centre, Department of Dermatology and Allergy, Copenhagen University Hospital, Herlev-Gentofte, Hellerup, Denmark.
Background: Chronic hand eczema (CHE) is a common skin disease with different subtypes, but knowledge of the molecular patterns associated with each subtype is limited.
Objective: To characterize the CHE transcriptome across subtypes.
Methods: Using RNA-sequencing, we studied the transcriptome of 220 full-thickness skin biopsies collected from palms, dorsa, and arms from 96 patients with CHE and/or atopic dermatitis (AD) and 32 healthy controls.
Diabetes Obes Metab
January 2025
Department of Epidemiology and Biostatistics, Key Laboratory of Molecular Cancer Epidemiology, Key Laboratory of Prevention and Control of Major Diseases in the Population, Ministry of Education, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin Medical University, Tianjin, China.
Background: Fatty liver disease may be associated with increased risks of intrahepatic and extrahepatic cancers. Our objective was to investigate associations between new subcategories of steatotic liver disease (SLD) recently proposed by nomenclature consensus group and cancer risk.
Methods: A total of 283 238 participants from the UK Biobank were included.
Int J Mol Sci
December 2024
Digital Omics Research Center, Korea Basic Science Institute, Ochang 28119, Republic of Korea.
The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in hundreds of millions of infections and millions of deaths globally. Although vaccination campaigns are mitigating the pandemic, emerging viral variants continue to pose challenges. The spike (S) protein of SARS-CoV-2 plays a critical role in viral entry by binding to the angiotensin-converting enzyme 2 (ACE2) receptor, making both proteins essential targets for therapeutic and vaccine development.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Thoracic Surgery, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, Cancer Hospital Affiliated to University of Electronic Science and Technology of China, Chengdu, Sichuan, China.
SIRT6, a member of the sirtuin protein family, is recognized as a tumor suppressor. This study investigates the evolutionary history of the SIRT gene family and examines the selective pressures shaping their functional divergence. Insights into the evolution of these genes may enhance our understanding of their roles in disease pathology.
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