Purpose: To investigate cell cycle effects and relative biological effectiveness (RBE) of α-particles from the clinically relevant radionuclide Astatine-211 ((211)At), using X-rays as reference radiation. Double-strand breaks (DSB), non-DSB clusters containing oxidised purines and clonogenic survival were investigated.
Materials And Methods: Asynchronous V79-379A fibroblasts or cells synchronised with mimosine in G1, early, mid and late S phase or in mitosis were irradiated with X-rays (100 kV(p)) or (211)At (mean linear energy transfer (LET) 110 keV/μm). Induction of DSB and clusters was determined using pulsed-field gel electrophoresis with fragment analysis. Cell survival was obtained with the clonogenic assay.
Results: In asynchronous cells RBE for DSB- and cluster-induction was 3.5 and 0.59, respectively. RBE for 37% cell survival was 8.6. In different cell cycle phases RBE varied from 1.8-3.9 for DSB and 3.1-7.9 for 37% survival (survival at 2 Gy was 6.9-38 times lower after α-irradiation). (211)At induced 6 times more DSB and X-rays induced 11 times more DSB in mitotic cells with highly compacted chromatin relative G1.
Conclusions: The radio-response is cell cycle dependent and differs between proliferating and non-cycling cells for both low- and high-LET radiation, resulting in a variation in RBE of α-particles between 1.8 and 8.6.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.3109/09553002.2011.538127 | DOI Listing |
ACS Biomater Sci Eng
January 2025
Nano 2 Micro Material Design Lab, Department of Chemical Engineering and Technology, IIT (BHU), Varanasi 221005, India.
Herein, fluorescent calcium carbonate nanoclusters encapsulated with methotrexate (Mtx) and surface functionalized with chitosan (25 nm) (@Calmat) have been developed for the imaging and treatment of triple-negative breast cancer (TNBC). These biocompatible, pH-sensitive nanoparticles demonstrate significant potential for targeted therapy and diagnostic applications. The efficacy of nanoparticles (NPs) was evaluated in MDA-MB-231 TNBC cell lines.
View Article and Find Full Text PDFPharmacol Rep
January 2025
Razi Drug Research Centre, Iran University of Medical Sciences (IUMS), Tehran, Iran.
Melatonin, renowned for regulating sleep-wake cycles, also exhibits notable anti-aging properties for the skin. Synthesized in the pineal gland and various tissues including the skin, melatonin's efficacy arises from its capacity to combat oxidative stress and shield the skin from ultraviolet (UV)-induced damage. Moreover, it curbs melanin production, thereby potentially ameliorating hyperpigmentation.
View Article and Find Full Text PDFAdv Biotechnol (Singap)
October 2023
Institute of Medical Plant Physiology and Ecology, School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China.
Optimizing central carbon metabolism (CCM) represents an attractive and challenging strategy to improve the biosynthesis of valuable chemicals due to the complex regulation of the CCM in yeast. In this study, we triggered the similar Warburg effect of cancer cells in yeast strains by introducing the human hypoxia-inducible factor-1 (HIF-1) complex, which regulated the expression of numerous enzymes involved in CCM and redirected the metabolic flux from glycolysis to tricarboxylic acid cycle. This redirection promoted the production of squalene to a 2.
View Article and Find Full Text PDFMol Biol Rep
January 2025
Department of Cellular Pathology, Institute for Developmental Research, Aichi Developmental Disability Center, 713-8 Kamiya, Kasugai, 486-0392, Japan.
Background: RAB11 is a small GTP-binding protein that regulates intracellular trafficking of recycling endosomes and is thereby involved in several neural functions. Highly similar RAB11 isoforms are encoded by RAB11A and RAB11B genes, and their pathogenic variants are associated with similar neurodevelopmental disorders, suggesting that RAB11A and RAB11B play similar and important roles in brain development. However, the detailed distribution patterns of these isoforms in various organs, including the brain, remain undetermined.
View Article and Find Full Text PDFCell Tissue Res
January 2025
Diabetes Research Center, Qatar Biomedical Research Institute (QBRI), Qatar Foundation (QF), Hamad Bin Khalifa University (HBKU), Doha, Qatar.
Impaired insulin secretion contributes to the pathogenesis of type 1 diabetes mellitus through autoimmune destruction of pancreatic β-cells and the pathogenesis of severe forms of type 2 diabetes mellitus through β-cell dedifferentiation and other mechanisms. Replenishment of malfunctioning β-cells via islet transplantation has the potential to induce long-term glycemic control in the body. However, this treatment option cannot widely be implemented in clinical due to healthy islet donor shortage.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!