The aims of this study were to investigate the sensitivity of Tradescantia pallida 'Purpurea' to genotoxicity induced by ozone, by means of the micronucleus (MCN) bioassay, to verify whether the intensity of genotoxic responses in inflorescences is modulated by concentrations of ascorbic acid (AA) in their bracts, and/or by air temperature variations during the progress of the bioassay, and to define the time lag necessary after ozone exposure to observe maximal genotoxic effects. Flowering branches were exposed to filtered air (control) and to 60 ppb of ozone (ozone) for 3h in fumigation chambers during spring, autumn, winter and summer. After exposure, they were maintained for 24-120 h under filtered air for recovery. A sub-group of each treatment was taken every 24h, when MCN was scored in inflorescences and the levels of AA were determined in bracts. Ozone caused a significant increase in the frequency of MCN after 24-120 of recovery, compared to measurements in inflorescences from the control treatment, but maximal MCN rate was reached between 72 and 120 h of recovery. The highest percentages of MCN in both fumigation treatments were found during the winter experiment. Ozone exposure did not induce significant changes in the content of AA. However, it was positively influenced by daily amplitude of air temperature during the period of the bioassay. The intensity of genotoxic damage and the time lag necessary to visualize an enhanced number of MCN depended on the levels of ascorbic acid in bracts 24h before MCN scoring and on the daily amplitude of air temperature during the development of the bioassay. Narrower ranges between daily maximum and minimum temperatures (around 4 degrees C) during the days of experiment seemed to promote a more efficient diagnostic of genotoxiciy induced by ozone.
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http://dx.doi.org/10.1016/j.mrgentox.2009.02.007 | DOI Listing |
J Cereb Blood Flow Metab
January 2025
Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK.
To what extent sildenafil, a selective inhibitor of the type-5 phosphodiesterase modulates systemic redox status and cerebrovascular function during acute exposure to hypoxia remains unknown. To address this, 12 healthy males (aged 24 ± 3 y) participated in a randomized, placebo-controlled crossover study involving exposure to both normoxia and acute (60 min) hypoxia (Fi = 0.14), followed by oral administration of 50 mg sildenafil and placebo (double-blinded).
View Article and Find Full Text PDFJ Clin Med
January 2025
Eye Clinic, ASST Santi Paolo e Carlo Hospital, University of Milan, 20142 Milan, Italy.
Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal diseases characterized by the progressive loss of photoreceptor function, visual impairment, and, ultimately, blindness. While gene therapy has emerged as a promising therapy, it is currently available only for the RPE65 gene mutation, leaving many patients without targeted genetic treatments. Non-surgical interventions may help in managing the progression of RP and improving patients' quality of life.
View Article and Find Full Text PDFLife (Basel)
January 2025
Department of Clinical Medicine and Surgery, University of Naples "Federico II", 80131 Naples, Italy.
The COVID-19 pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has profoundly impacted global health, with pneumonia emerging as a major complication in severe cases. The pathogenesis of COVID-19 is marked by the overproduction of reactive oxygen species (ROS) and an excessive inflammatory response, resulting in oxidative stress and significant tissue damage, particularly in the respiratory system. Antioxidants have garnered considerable attention for their potential role in managing COVID-19 pneumonia by mitigating oxidative stress and modulating immune responses.
View Article and Find Full Text PDFBiomedicines
January 2025
Frankel Cardiovascular Center, Department of Medicine, University of Michigan, Ann Arbor, MI 48109, USA.
Comorbidities related to cardiovascular disease (CVD) and environmental pollution have emerged as serious concerns. The exposome concept underscores the cumulative impact of environmental factors, including climate change, air pollution, chemicals like PFAS, and heavy metals, on cardiovascular health. Chronic exposure to these pollutants contributes to inflammation, oxidative stress, and endothelial dysfunction, further exacerbating the global burden of CVDs.
View Article and Find Full Text PDFBiology (Basel)
January 2025
Unilever R&D Shanghai, 66 Lin Xin Road, Linkong Economic Development Zone, Shanghai 200335, China.
The skin acts as the first line of defense against various environmental stressors, such as solar ultraviolet radiation, visible light, pollution particles and ozone. Simultaneous exposure to different stressors is common in everyday life but has been less studied than exposure to single stressors. Herein, the combined effects of a chemical pollutant (ozone) and a UV radiation stressor (UVSSR) were investigated on a 3D pigmented living skin equivalent model.
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