Etoposide is bound to plasma albumin (94%). Previous studies have revealed altered protein binding of etoposide in cancer patients. This has clinical implications since only the free fraction is considered pharmacologically active. We have studied the etoposide protein binding in 11 children (eight acute lymphocytic leukemia, two malignant histiocytosis, and one oligodendroglioma; age 1-17 years) and 46 adult patients (28 acute myelocytic leukemia, eight lymphoma, one multiple myeloma, and nine small cell lung cancer; age 38-81 years). All patients were treated with etoposide 50-200 mg/m2 i.v. or orally. Plasma from ten healthy volunteers, 26-50 years of age, was spiked with etoposide, 10 micrograms/ml, and the protein binding was compared with that in patient samples. The free etoposide concentration was determined by high performance liquid chromatography (HPLC) after ultrafiltration at room temperature. The free etoposide fraction was lower, 2.5 +/- 0.6% (mean +/- SD), in the children compared with 5.0 +/- 3.6% in adult cancer patients. In plasma from healthy adults it was 3.2 +/- 0.3%. It is concluded that children have significantly lower levels of free etoposide compared with adult patients (P = 0.03) as well as with healthy subjects (P = 0.001), which is likely to affect metabolism and renal clearance as well as cellular uptake of the drug.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/0304-3835(96)04308-x | DOI Listing |
J Biomol Struct Dyn
March 2025
Department of Chemistry, Jamia Millia Islamia, New Delhi, India.
1,3,4-Oxadiazole-based heterocyclic analogs (3a-3m) were synthesized cyclization of Schiff bases with substituted aldehydes in the presence of bromine and acetic acid. The structural clarification of synthesized molecules was carried out with various spectroscopic techniques such as FT-IR,H and C-NMR, UV-visible spectroscopy, and mass spectrometry. antifungal activity was performed against , and and analogs 3g, 3i, and 3m showed potent MIC at 200 µg/ml and excellent ZOI measurements of 17-21 nm.
View Article and Find Full Text PDFJACS Au
January 2025
Department of Physics, Freie Universität Berlin, Arnimallee 14, Berlin 14195, Germany.
Interactions of polyelectrolytes (PEs) with proteins play a crucial role in numerous biological processes, such as the internalization of virus particles into host cells. Although docking, machine learning methods, and molecular dynamics (MD) simulations are utilized to estimate binding poses and binding free energies of small-molecule drugs to proteins, quantitative prediction of the binding thermodynamics of PE-based drugs presents a significant obstacle in computer-aided drug design. This is due to the sluggish dynamics of PEs caused by their size and strong charge-charge correlations.
View Article and Find Full Text PDFJACS Au
January 2025
Program in Chemical Biology, Department of Chemical Physiology and Biochemistry, Proteomics Shared Resources, Knight Cancer Institute, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, Oregon 97239, United States.
Proteins regulate biological functions through the formation of distinct protein complexes. Identification and characterization of these protein-protein interactions are critical to deciphering their mechanism of action. Different antibody-based or cross-linking-based methods have been developed to identify the protein-protein interactions.
View Article and Find Full Text PDFJACS Au
January 2025
Department of Biomedical Engineering, University of Virginia, Box 800759, Charlottesville, Virginia 22908, United States.
Cell entry by enveloped viruses involves a set of multistep, multivalent interactions between viral and host proteins as well as manipulation of nanoscale membrane mechanics by these interacting partners. A mechanistic understanding of these events has been challenging due to the complex nature of the interactions and the event-to-event heterogeneity involved. Single-virus microscopy has emerged as a powerful technique to probe viral binding and fusion kinetics.
View Article and Find Full Text PDFJACS Au
January 2025
Applied Molecular Enzyme Chemistry, Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark.
Interfacial enzyme catalysis is widespread in both nature and industry. Granular starch is a sustainable and abundant raw material for which a rigorous correlation of the surface structure with enzymatic degradation is lacking. Here pullulanase-catalyzed debranching of 12 granular starches varying in amylopectin contents and branch chain contents and lengths is shown to present a biphasic relationship characteristic of the Sabatier principle.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!