Dasal Vasantharaja; Venugopal Ramalingam; Shanmugam Thangapandiyan; Nagarajan Sridhar; Gaddam Dayanand Reddy
Abstract
Nanoparticles (NPs) are extensively being used in modern life due to their distinctive properties like small size having large surface area. Titanium dioxide (TiO2) NPs are mostly used in cosmetic products, food additives, pharmaceuticals and electronics. They are capable of inducing oxidative stress ...
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Nanoparticles (NPs) are extensively being used in modern life due to their distinctive properties like small size having large surface area. Titanium dioxide (TiO2) NPs are mostly used in cosmetic products, food additives, pharmaceuticals and electronics. They are capable of inducing oxidative stress in both animals and human. The intention of this study was to find out the hepatotoxic effect of TiO2 NPs on the male Wistar rats. The animals were divided in to three groups. First group received normal saline; Second group received TiO2 NPs (50 mg/kg/bw) for 14 days continuously, while third group received TiO2 NPs (100 mg/kg/bw) for the same duration. The increased levels of specific markers AST, ALT, ALP, LDH and GGT along with the TBARS, LOOH, CD and PC in the liver clearly shows the hepatotoxic action of TiO2. The hepatotoxic nature of TiO2 NPs was more evidenced by the diminished activity of antioxidant enzymes levels and also showed augmented DNA damage and fragmentation in hepatocytes. In conclusion, the data indicated that TiO2 NPs induced oxidative stress which produces hepatotoxicity in the rat liver.
Anna Varizhuk; Vyacheslav Severov; Galina Pozmogova
Abstract
It is now commonly acknowledged that G-rich polynucleotide sites can fold into G-quadruplex (G4) structures in vivo. In terms of molecular programming, the G4-folding propensity can be regarded as a build-in nucleic acid function with multiple implications for genomic regulation. Here we review several ...
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It is now commonly acknowledged that G-rich polynucleotide sites can fold into G-quadruplex (G4) structures in vivo. In terms of molecular programming, the G4-folding propensity can be regarded as a build-in nucleic acid function with multiple implications for genomic regulation. Here we review several important advances in the studies of G4 self-assemblies in genomic context. We discuss prerequisites and consequences of G4 formation upon transcription or replication and analyze recent data on G4-dependent genomic rearrangements, including translocation and recombination. Hypothetical mechanisms of those G4-dependent rearrangements suggest self-association of G-rich sites. We outline the general molecular basis for possible self-association pathways, i.e., formation of intermolecular G4 assemblies or interquadruplex stacking. Intermolecular G4s and multimeric G4 stacks attract widespread interest as scaffolds for the development of complex junctions in DNA nanotechnology and have prospects in aptamer design, but in this review we focus on fundamental aspects of such higher-order G4 assemblies.
Kumud Kant Awasthi; Rajbala Verma; Anjali Awasthi; Kamlendra Awasthi; Inderpal Soni; P. J. John
Abstract
Silver nanoparticles (Ag NPs) has resulted their incorporation into consumer products due to their extensive application in health, electronic, and household products. In particular, the oral toxicity of Ag NPs is of particular concern to ensure public health. For the present study, a genotoxic and cytotoxic ...
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Silver nanoparticles (Ag NPs) has resulted their incorporation into consumer products due to their extensive application in health, electronic, and household products. In particular, the oral toxicity of Ag NPs is of particular concern to ensure public health. For the present study, a genotoxic and cytotoxic approach was employed to elucidate the activity of 5 nm size and spherical shaped Ag NPs in liver cells of Swiss albino mice by using alkaline comet assay. Statistically significant DNA damage raise the concern about the safety associated with the applications of the Ag NPs. The result showed that Ag NPs induced a significant concentration dependent increase in the frequency of tailed nuclei (DNA damage), tail moment, %DNA in the tail, and tail length in the liver cells. Additionally significant histopathological alterations were also observed. The results of present study suggest that exposure to silver nanoparticles has the potential to cause genetic damage.