There has recently been an increase in the usage of TiO nanoparticles (NPs). P25 TiO NPs, a mixture of anatase and rutile phase in 3:1 ratio, are generally used for photocatalytic applications because both phases exhibit a synergistic effect on the photocatalytic activity of the TiO NPs. In the present study, increased toxicity of UVA-pre-irradiated P25 TiO NPs on freshwater algae Scenedesmus obliquus was assessed under visible light and dark exposure conditions at actual low concentrations (0.3, 3 and 35 μM of Ti). Photocatalytic property of P25 TiO NPs caused disaggregation of UVA-pre-irradiated NPs, thus significantly decreasing the mean hydrodynamic diameter (MHD) (188.74 ± 0.54 nm) than that of non-irradiated NPs (232.26 ± 0.44). This decrease in diameter of UVA-pre-irradiated NPs may increase its biological activity towards algal samples. All concentrations of pre-irradiated NPs, under both light and dark conditions, showed a significantly lesser cell viability (p < 0.001) when compared with non-irradiated NPs. Increased production of ROS, antioxidant enzymes and lipid peroxidation supported the viability data. Higher exopolysaccharide production and more nuclear damage were observed for pre-irradiated NPs. NP uptake was also more for the pre-irradiated NPs on treated samples when compared with non-irradiated NPs on treated samples, which, in turn, established the higher toxic potential of UVA-pre-irradiated TiO NPs. This study improves our understanding of the toxic effects of UVA-pre-irradiated TiO NPs on freshwater algae, thereby emphasising the need for ecological risk assessments of metal oxide nanoparticles in a natural experimental medium.

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The production of different size and shape silver nanoparticles (AgNPs) has increased considerably in recent years due to several commercial and biological applications. Here, rod-shaped AgNPs (SNRs) were prepared using the microwaveassisted method and characterised by ultraviolet-visible spectroscopy, and transmission electron microscopy analysis. The present study aims to investigate the cyto-genotoxic effect of various concentrations (5, 10, and 15 µM) of SNRs using Allium cepa model. As a result, concentration-dependent cyto-genotoxic effect of SNRs was observed through a decrease in the mitotic index, and an increase in the chromosomal aberrations such as chromosome break, disturbed metaphase, and anaphase bridge. To check the impact of Ag + ions, 15 µM silver nitrate (AgNO 3) was prepared and tested in all the assays. Furthermore, cell viability and different reactive oxygen species assays were performed to test the cytotoxicity evaluation of SNRs. The authors found that in all the tested assays, SNRs at high concentrations (15 µM) and AgNO 3 (15 µM) were observed to cause maximal damage to the roots. Therefore, the current study implies that the cytotoxicity and genotoxicity of SNRs were dependent on the concentration of SNRs.

Aim: Our study focuses on the liposome-based nanoformulation, which can encapsulate Pterostilbene for its subsequent testing in relevant, model systems for cancer. Background: Pterostilbene, a plant-derived, hydrophobic, dietary stilbenoid, has been studied for its ability to induce cell death and regulate caspases in the different types of cancer cells. The potential of this drug can be improved by formulating a suitable vehicle for its delivery. Biocompatible, lipid-based nanoparticles called liposomes have been studied as a potent delivery vehicle for drugs in pre-clinical as well as in clinical studies. Liposomes can improve the drug uptake and bioavailability of the drugs. Materials and Methods: Pterostilbene loaded liposomes were constructed using DOTAP and Cholesterol, by the Thin-Film Hydration method. Along with the loaded liposomes, blank liposomes (only DOTAP and Cholesterol, without Pterostilbene) were also constructed. The liposomes were characterized for their size, Polydispersity Index (PDI) and Zeta potential using DLS. Shape of the liposomes was analysed using TEM. Encapsulation Efficiency (EE) of the Pterostilbene loaded liposomes was determined. Also, UV-Vis spectrophotometer was used to ensure that Pterostilbene was encapsulated inside the liposomes and there was no interaction between the drug and the lipids. Results: Liposomes were composed of DOTAP and Cholesterol with molar ratios 2:1. The DLS showed that the size of the Pterostilbene-loaded liposomes was 435.6±5 nm (n=3), PDI was 0.5±0.07 (n=3) and Zeta potential was -16.4±0.5 mV (n=3). The drug encapsulation efficiency was found to be 97.5±0.8% (n=3). Conclusion: Reproducibility in the results (DLS and EE data for Pterostilbene-encapsulated liposomes) provides a sound, scientific basis for evaluating their cell death potential of Pterostilbene loaded liposomes against cancer cells in comparison with that of free Pterostilbene (parent compound). Also, the experimental flow of ours can be used as a teaching tool by educators in drug delivery and allied fields.

Primordial germ cells (PGCs) provide an excellent tool to better understand ancestor-descendent relationships as well as the efficiency and molecular mechanisms governing pluripotency in the reprogramming of somatic cells, since the latter type of cells have a relatively lower efficiency of conversion to pluripotent cells. This kind of comparison has gained credence from the commonalities regarding the expression of key transcription factors such as octamer-binding transcriptionhttp://en.wikipedia.org/wiki/Transcription_ factor factor-4 (Oct3/4), SRY-related HMG box (Sox2), myelocytomatosis (c-Myc), and Nanog, as well as redundancy in terms of Kruppel-like factor 2 (Klf2), Kruppel-like factor 5 (Klf5), estrogen-related receptor beta (Esrrb), and estrogen-related receptor gamma (Esrrg) compensating for the absence of Kruppel-like factor 4 (Klf4). However, the exogenous addition of any one of these factors was found to be important, thereby implying that the expression level is important. L-Myelocytomatosis (L-myc) was shown to improve reprogramming efficiency without affecting tumorigenic potential. Molecular aspects of epigenetic reprogramming during the acquisition of pluripotency, as well as tumorigenic potential, have also been discussed, thus providing an understanding of the factors that can improve the former without increasing the possibility of neoplastic transformation. An improved understanding of the molecular events would pave the way for the development and use of endogenous biomolecules as well as currently available chemical reprogrammers for improving the efficiency of conversion of PGCs into cells of the stem cell lineage. Such chemicals, when adequately tested, can possibly be an alternative to viral vectors, since the introduced transgenes can become oncogenic.