Inhibition of B(a)P induced strand breaks in presence of curcumin

Incidence of cancer at different sites may be related to oxidative damage to host genome by genotoxicants. These oxidative actions may be modified by phytochemicals present in foods. The non-nutritive dietary constituents which possess antimutagenic property appear to be promising chemopreventive agents. This study reports the protective effect of curcumin on B(a)P induced DNA damage in human peripheral blood lymphocyte cells. The study group consisted of 10 male smokers, 10 non-smokers and 10 non-smoking females aged between 25 and 45. The DNA damage was assessed using comet assay. In all the groups curcumin showed a dose-dependent inhibitory effect. The effect appeared to be sex dependent. There was no correlation between DNA damage and GST-Mu levels and levels of micronutrients namely Vitamins A, E and beta carotene. The results of this study are in line with our earlier observations on turmeric/curcumin as a potential chemopreventer.     

Cytogenetic effects of replicating and nonreplicating strains of influenza virus on male germ cells of mice

Summary Evidence is presented to demonstrate that replicating (A₂ and B) and nonreplicating (C) strains of influenza virus were capable of inducing higher percentages of chromosome anomalies in spermatocytes of mice inoculated either IP or IN than were seen in controls.This report is part of the Ph. D. thesis of this author     

Metabolism of lysine-chromium complex in Saccharomyces cerevisiae

Saccharomyces cerevisiae which cannot utilize lysine as a sole nitrogen source is shown to metabolize a Lysine 3 Cr³⁺ (1:1) complex synthesized, as a combined nitrogen and carbon source. It induces rapid uptake of lysine and prevents loss of viability, in contrast with free lysine. That complexation with trivalent chromium has the effect of profoundly influencing intracellular distribution and metabolism of the liganded amino acid is demonstrated.     

The inhibitory effect of enfenamic acid (Tromaril) on hepatic gluconeogenesis in Swiss albino mice

Enfenamic acid, a new non-steroidal anti-inflammatory drug was studied for its effect on hepatic gluconeogenesis and some of the enzymes involved in this process in mice. Incubation of liver cells in the presence of 1.0 mM enfenamic acid inhibited the output of glucose. And also the in vitro addition of various concentrations of enfenamic acid (0.25 to 3.0 mM) to the tissue extracts of liver inhibited the activities of important gluconeogenic enzymes such as pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase (PEPCK) and fructose 1,6-diphosphatase (FDPase). The oral and intraperitoneal administrations of the drug for 15 and 3 days respectively, exhibited significant decrease in the hepatic PC, PEPCK and FDPase. These findings indicated that the impairment of gluconeogenesis might be due to the inactivation of the enzymes by the drug.     

Influence of nitrogen source on hydrogen generation by a photosynthetic bacterium

Axenic culture of photosynthetic purple sulphur bacterium, isolated from a paper mill effluent, grew best with ammonium chloride as nitrogen source. Cells grown with N₂ or ammonium chloride produced hydrogen with initial lag periods of 24 and 48 h, respectively. The maximum amount of hydrogen was evolved by cells grown with N₂ and with malate as electron donor.R. Lakshmi is with the Microbial Physiology Laboratory, Department of Botany, and H. Polasa is with the Department of Microbiology, Osmania University, Hyderabad 500 007, India.     

Evaluation of the anti-inflammatory drug indomethacin, for its genotoxicity in mice

Indomethacin, a non-steroidal anti-inflammatory drug was assessed for its genotoxicity in Swiss male mice employing bone marrow micronucleus induction, abnormal sperm formation and the induction of meiotic chromosome anomalies in spermatocytes as the test parameters. The results showed that the test compound was toxic to the genetic material in the dose range of 12-36 mg/kg body weight.     

Mixed-ligand complexes of platinum(II) as curing agents for pBR322 and pBR329 (ColE1) plasmids in Escherichia coli

The mixed-ligand complexes of platinum(II) [Pt(Gly)(uracil)Cl2].H2O and [Pt(His)(adenine)]-Cl.2H2O eliminated multicopy plasmids with the ColE1 origin of replication in Escherichia coli with 100% frequency. However, plasmids of the IncF1, H1 and X groups were totally refractory to these agents under similar conditions.     

Elimination of ColE1 (pBR322 and pBR329) plasmids in Escherichia coli by α-santonin

alpha-Santonin, a compound extracted from the flower heads of Arthemisia maritima plant, was effective in elimination of small, multicopy, relaxed plasmids (pBR322 and pBR329 with CoLE1 origin of replication in Escherichia coli, whereas plasmids of IncF1, H1 and X group were totally refractory under similar conditions, suggesting that this agent was specific in curing the CoLE1 group of plasmids.