The Impact of Silver Codoping on Tb Luminescence in Lithium Tetraborate Glasses.

Spectroscopic properties of Tb-doped and Tb-Ag codoped lithium tetraborate (LTB) glasses with LiBO (or LiO-2BO) composition are investigated and analysed using electron paramagnetic resonance (EPR), optical absorption, photoluminescence (PL) and photoluminescence excitation (PLE) spectra, PL decay kinetics and absolute quantum yield (QY) measurements. PL spectra of the investigated glasses show numerous narrow emission bands corresponding to the D → F (J = 6-0) and D → F (J = 5-3) transitions of Tb (4f) ions. The most intense PL band of Tb ions at 541 nm (D → F transition) is characterised by a lifetime slightly exceeding 2.

Structural and spectroscopic studies of lithium tetraborate glass co-doped with Sm and Cu.

The local structure and spectroscopic properties of Cu-Sm co-doped LiBO glass have been studied using XRD, EPR, UV-Vis-NIR absorption and luminescence methods and compared with the corresponding results for Sm-doped and Cu-doped LiBO glasses. The EPR spectrum reveals an axially-symmetric signal with a characteristic hyperfine structure belonging to Cu ions. The Cu/Cu ratio was determined.

Aspirin as a Potential Geroprotector: Experimental Data and Clinical Evidence.

Aging is a biological process with effects at the molecular, cellular, tissue, organ, system, and organismal levels and is characterized by decline in physical function and higher risks of age-related diseases. The use of anti-aging drugs for disease prevention has become a high priority for science and is a new biomedicine trend. Geroprotectors are compounds which slow aging and increase lifespan of the organism in question.

Effect of aflatoxin B, benzo[a]pyrene, and methapyrilene on transcriptomic and epigenetic alterations in human liver HepaRG cells.

The increasing number of man-made chemicals in the environment that may pose a carcinogenic risk highlights the need for developing reliable time- and cost-effective approaches for carcinogen detection and identification. To address this issue, we investigated the utility of high-throughput microarray gene expression and next-generation genome-wide DNA methylation sequencing for the in vitro identification of genotoxic and non-genotoxic carcinogens. Terminally differentiated and metabolically competent human liver HepaRG cells were treated at minimally cytotoxic concentrations of (i) the genotoxic human liver carcinogen aflatoxin B (AFB1) and its structural non-carcinogenic analog aflatoxin B (AFB2); (ii) the genotoxic human lung carcinogen benzo[a]pyrene (B[a]P) and its non-carcinogenic isomer benzo[e]pyrene (B[e]P); and (iii) the non-genotoxic liver carcinogen methapyrilene for 72 h and transcriptomic and DNA methylation profiles were examined.

Cellular and Molecular Effects of Prolonged Low-Level Sodium Arsenite Exposure on Human Hepatic HepaRG Cells.

Inorganic arsenic is a human carcinogen associated with several types of cancers, including liver cancer. Inorganic arsenic has been postulated to target stem cells, causing their oncogenic transformation. This is proposed to be one of the key events in arsenic-associated carcinogenesis; however, the underlying mechanisms for this process remain largely unknown.