AI Article Synopsis
Article Abstract
Background: We have developed a new clinical research approach for the quantification of cellular proliferation in human infants to address unanswered questions about tissue renewal and regeneration. The approach consists of oral 15N-thymidine administration to label cells in S-phase, followed by Multi-isotope Imaging Mass Spectrometry for detection of the incorporated label in cell nuclei. To establish the approach, we performed an observational study to examine uptake and elimination of 15N-thymidine. We compared at-home label administration with in-hospital administration in infants with tetralogy of Fallot, a form of congenital heart disease, and infants with heart failure.
Methods: We examined urine samples from 18 infants who received 15N-thymidine (50 mg/kg body weight) by mouth for five consecutive days. We used Isotope Ratio Mass Spectrometry to determine enrichment of 15N relative to 14N (%) in urine.
Results/findings: 15N-thymidine dose administration produced periodic rises of 15N enrichment in urine. Infants with tetralogy of Fallot had a 3.2-fold increase and infants with heart failure had a 4.3-fold increase in mean peak 15N enrichment over baseline. The mean 15N enrichment was not statistically different between the two patient populations (p = 0.103). The time to peak 15N enrichment in tetralogy of Fallot infants was 6.3 ± 1 hr and in infants with heart failure 7.5 ± 2 hr (mean ± SEM). The duration of significant 15N enrichment after a dose was 18.5 ± 1.7 hr in tetralogy of Fallot and in heart failure 18.2 ± 1.8 hr (mean ± SEM). The time to peak enrichment and duration of enrichment were also not statistically different (p = 0.617 and p = 0.887).
Conclusions: The presented results support two conclusions of significance for future applications: (1) Demonstration that 15N-thymidine label administration at home is equivalent to in-hospital administration. (2) Two different types of heart disease show no differences in 15N-thymidine absorption and elimination. This enables the comparative analysis of cellular proliferation between different types of heart disease.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10810423 | PMC |
| http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0295651 | PLOS |
Publication Analysis
Top Keywords
Similar Publications
Ammonia synthesis via an engineered nitrogenase assembly pathway in .
Nat Catal
October 2024
Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900.
Heterologous expression of nitrogenase has been actively pursued because of the far-reaching impact of this enzyme on agriculture, energy and environment. Yet, isolation of an active two-component, metallocentre-containing nitrogenase from a non-diazotrophic host has yet to be accomplished. Here, we report the heterologous synthesis of an active Mo-nitrogenase by combining genes from and in .
View Article and Find Full Text PDFA Novel System for Simultaneous Real-Time Determination of N-Enriched Ammonia, Hydroxylamine, Nitrite, and Nitrate.
Anal Chem
December 2024
Institute of Carbon Neutrality, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100091, China.
Ammonium (NH), hydroxylamine (NHOH), nitrite (NO), and nitrate (NO) account for the most important reactive nitrogen (N) species in the N cycle, playing a key role in N elimination and N retention, as well as the production of nitrogenous trace gases. However, it is still challenging to fulfill simultaneous real-time determination of all four N compounds enriched in N. This study successfully established a novel system by coupling an utomatic imultaneous ample reparation unit to a embrane nlet ass pectrometer (4n-ASSP-MIMS) for rapid online N fraction analysis of all four key compounds in the N cycle.
View Article and Find Full Text PDFConvenient syntheses of isotopically labeled pyrimidine 2'-deoxynucleosides and their 5-hydroxy oxidation products.
Nucleosides Nucleotides Nucleic Acids
December 2024
Department of Chemistry, Stanford University, Stanford, CA, USA.
Hydrolytic and oxidative damage to pyrimidine nucleobases in DNA represents a significant source of mutations in the human genome. To better understand how these lesions are incorporated and repaired in human cells, it is desirable to have ready access to isotopically enriched nucleosides for use in isotope tracing and mass spectrometry-based quantification experiments. Here we report on improved syntheses of deoxyuridine, deoxycytidine, 5-hydroxydeoxyuridine, and 5-hydroxydeoxycytidine nucleosides labeled with C and N.
View Article and Find Full Text PDFAnalysis of chemical exchange in iridium N-heterocyclic carbene complexes using heteronuclear parahydrogen-enhanced NMR.
Commun Chem
December 2024
Section Biomedical Imaging, Molecular Imaging North Competence Center (MOIN CC), Department of Radiology and Neuroradiology, University Medical Center Kiel, Kiel University, Am Botanischen Garten 14, 24118, Kiel, Germany.
The signal amplification by reversible exchange process (SABRE) enhances NMR signals by unlocking hidden polarization in parahydrogen through interactions with to-be-hyperpolarized substrate molecules when both are transiently bound to an Ir-based organometallic catalyst. Recent efforts focus on optimizing polarization transfer from parahydrogen-derived hydride ligands to the substrate in SABRE. However, this requires quantitative information on ligand exchange rates, which common NMR techniques struggle to provide.
View Article and Find Full Text PDFA Proof-of-Principle Study for δN Measurements of Aqueous Dissolved Nitrate With a Modified LC-IRMS Interface.
Rapid Commun Mass Spectrom
February 2025
Instrumental Analytical Chemistry, University of Duisburg-Essen, Essen, Germany.
Rationale: The analysis of nitrogen isotopes in aqueous dissolved nitrate is an effective method for identifying pollution sources and offers the potential to study the nitrogen cycle. However, the measurement of nitrogen isotope ratios of nitrate still requires extensive sample preparation or derivatization.
Methods: In this study, a modified commercially available liquid chromatography-isotope ratio mass spectrometer (LC-IRMS) interface is presented that enables automated measurement of δN signatures from nitrate by online reduction of nitrate in two consecutive steps.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!