• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.1
• /
• pp.130-136
• /
• 1997

Total parenteral nutritional effect was induced by surgical creation of Thiry-Vella fistula(TVFs) in rats. Glutamine, glycine or nucleosides/nucleotide mixture in solution was injected into the loops for 2, 4, 6, 8 days. Control animals received a 0.9％ saline solution. Results include weight gain, total protein, DNA, ［$^3$H］ thymidine incorporation into DNA, morphometry of the intestine in both TVFs and intestine in continuity. Perfusion of nucleosides/nucleotide mixture into the bypassed loops caused an increase in total protein, DNA content, villous height, villous surface area in loops. The injection of glycine into loops caused an increase in ［$^3$H］ thymidine incorporation but the mean values of the protein and DNA contents were not significantly different from those in group Cont and group Nuc. Overall values for group Gln were slightly higher than those of the control but the differences were not statistically significant. This study suggests that this animal model may be useful for studying the effect of dietary factors on intestinal growth and maturation, separating the direct effect of diet from systemic effect on the intestine.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.10
• /
• pp.2318-2328
• /
• 2009

Massive deadenylation of adenine based-nucleosides induced by halogenated alkanes at the physiological condition have been observed. For the study of deadenylation effects by the different substituents and/or functionality in halogenated alkanes, diverse kinds of halogenated alkanes were incubated with adenine based-nucleosides (ddA, dA and adenosine) for 48 h at the physiological condition (pH 7.4, $37\;{^{\circ}C}$), which were analyzed by HPLC and further confirmed by LC-MS. Among the sixteen different halogenated alkanes, we observed massive deadenylation of nucleosides by 2-bromo-2-methylpropane, 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane. The order of deadenylation rate was highest in 2-bromo-2-methylpropane followed by 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane. In addition, time and dose response relationship of deadenylation in adenine based-nucleosides induced by 2-bromo-2-methylpropane, 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane at the physiological condition were investigated. In addition, deadenylation of calf thymus DNA induced by halogenated alkanes was also investigated. These results suggest that the toxic effect of certain halogenated alkanes might be from the depurination of nucleosides.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.12
• /
• pp.1790-1800
• /
• 2002

The DNA nucleosides(dA, dC, dG, dT)bound to gold nanoparticles (~13 nm) in aqueous solution has been studied as a probe by the SERS and their coordination structures have been proposed on the basis of them. According to UV-Visible absorption of gold nanoparticles after modifying with DNA nucleosides, the rates of absorption of dA, dC, and dG were much faster than that of dT as monitored by the aggregation kinetics at 700 nm. These data indicated that the nucleosides dA, dC, and dG had a higher affinity for the gold nanoparticles surface than nucleoside dT. As the result of SERS spectra, the binding modes of each of the nucleosides on gold nanoparticles have been assigned. A dA binds to gold nanoparticles via a N(7) nitrogen atom of the imidazole ring, which the C(6)-$NH_2$ group also participates in the coordination process. In the case of dC, it binds to the gold surface via a N(3) nitrogen atom of the pyrimidine ring with a partial contribution from the oxygen of C(2)=O group. A coordination of dG to the gold surfaces is also proposed. Although the dG has the two different nitrogens of a pyrimidine ring and the amino group, the N(1) nitrogen atom of a pyrimidine ring has a higher affinity after the hydrogen migrates to the amino group. Conversely, dT binds via the oxygen of the C(4)=O group of the pyrimidine ring. Accordingly, these data suggest that the nitrogen atom of the imidazole or the pyrimidine ring in the DNA nucleosides will bind more fast to the gold nanoparticles surfaces than the oxygen atom of the carbonyl group.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.10
• /
• pp.2309-2317
• /
• 2009

Depurination, the release of purine bases from nucleic acids by hydrolysis of the N-glycosidic bond, gives rise to alterations of the cell genome. Though cells have evolved mechanisms to repair these lesions, unrepaired apurinic sites have been shown to have two biological consequences: lethality and base substitution errors. 2-Bromopropane (2-BP) is used as an intermediate in the synthesis of pharmaceuticals, dyes, and other organics. In addition, 2-BP has been used as a replacement for chloroflurocarbons and 1,1,1-trichloroethane as a cleaning solvent in electronics industry. However, 2-BP was found to cause reproductive and hematopoietic disorders in local workers exposed to it. Owing to the toxicity of 2-BP, there has been a tendency to use 1-BP as an alternative cleaning solvent to 2-BP. However, 1-BP has also been reported to be neurotoxic in rats. Though $N^7$-guanine adduct of 2-BP has been reported previously, massive depurination of the nucleosides and calf thymus DNA was observed in this study. We incubated the nucleosides (ddG, dG, guanosine, ddA, dA and adenosine) with excess amount 2-BP at the physiological condition (pH 7.4, $37\;{^{\circ}C}$), which were analyzed by HPLC and LC-MS/MS. In addition, the time and dose response relationship of depurination in nucleosides induced by 2-bromopropane at the physiological condition was investigated. Similarly, incubation of calf-thymus DNA with the excess amount 2-BP at the physiological condition was also performed. In addition, the time and dose response relationship of depurination in calf-thymus DNA induced by 2-BP at the physiological condition was investigated. Those results suggest that the toxic effect of 2-BP could be both from the depurination of nucleosides and DNA adduct formation.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.12
• /
• pp.2949-2958
• /
• 2009

Massive deguanylation of guanine based-nucleosides induced by halogenated alkanes at the physiological condition have been observed. For the study of deguanylation effects by the different substituents and/or functionality in halogenated alkanes, diverse kinds of halogenated alkanes were incubated with guanine based-nucleosides (ddG, dG and guanosine) for 48 h at the physiological condition (pH 7.4, 37$^{\circ}C$), which were analyzed by HPLC and further confirmed by LC-MS. Among the sixteen different halogenated alkanes, we observed massive deguanylation of nucleosides by 2-bromo-2-methylpropane, 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane. The order of deguanylation rate was highest in 2-bromo-2-methylpropane followed by 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane. In addition, time and dose response relationship of deguanylation in guanine basednucleosides induced by 2-bromo-2-methylpropane, 2,3-dibromopropene, 2-bromopropane, bromoethane and 2-iodopropane at the physiological condition were investigated. Deguanylation of calf thymus DNA induced by halogenated alkanes was also investigated. These results suggest that the toxic effect of certain halogenated alkanes might be from the depurination of nucleosides.

• Journal of Nutrition and Health
• /
• v.31 no.4
• /
• pp.679-686
• /
• 1998

This study was performed to determine whether the infusion of nucleosides and a nucleotide mixture directly ito intestinal lumen can induce a regenerative effect on impaired intestinal mucosa. The effects of massive small bowel resention and also total parenteral nutrition were induced by surgical creation of Thirty-Vella fistual in male Sprague-Dawley rats. The rats received saline solution (Control group) or nucleosides and a nucleotide mixture(lower concentration group(Nucl) or higher concentration group (Nuc2) every two days into the fistula. Mucosal protein, DNA , ornithine decarboxylase(ODC) activity, and morphometry were evaluated at 9 or 21 days postoperation in the fistual and also in the residual ileal segment. On the 9th day, mucosal protein, DNA content, and villous surface area in the fistula and also in the residual ileum increased in rats that received nucleosides and a nucleotide mixture of lower concentration (Nuc 1). On the 21 th day, there were no significant differences in intestinal mucosa between the control group and the lower level nucleoside nucleotide mixture-treated group. The fistula villous height of the higher nucleosides and a nucleotide mixture group was higher than in the control rats. Fistula mucosal ODC activities were not significantly different between groups although the mucosal ODC activity of the residual ileal segment was increased on the 9th day. Our data suggests that this animal model is suitable for studying the effect of dietary factors on intestinal mucosal growth and regeneration after villous stropy , differentiating direct effects of diet on the intestine from systemic effects. It is also suggested that external nucleosides and nucleotides have supportive effects on intestinal mucosal regeneration.

• Asian-Australasian Journal of Animal Sciences
• /
• v.1 no.4
• /
• pp.219-222
• /
• 1988

Degradation of deoxyribonucleic acid(DNA) and ribonucleic acid(RNA) by cell-free extract of mixed rumen protozoa of buffalo rumen was investigated. DNA was observed to be degraded rapidly during an initial incubation period of 2 hr with simultaneous appearance of degradation products. RNA on the other hand recorded a rapid degradation during an initial incubation period of 1 hr. RNA degradation products appeared upto an incubation period of 2 hr. DNA was observed to degrade into oligo- and mononucleotides. pyrimidine nucleosides, purine nucleoside adenosine and bases xanthine, hypoxanthine and thymine. Degradation products of RNA comprised of pyrimidine nucleosides, purine nucleoside, adenosine and bases xanthine, hypoxanthine and uracil besides oligo- and mononucleotides.

• Bulletin of the Korean Chemical Society
• /
• v.10 no.2
• /
• pp.142-147
• /
• 1989

Fluorescence enhancements of ethidium bromide (EB) by solution species of low molecular weights such as DNA base molecules and nucleosides in water are reported. The degree of enhancements was determined by intensity as well as lifetime measurements for EB fluorescence. Experiments including solvent effects on absorbance and fluorescence spectra of EB, effects of protonation on the EB absorbance spectrum, and determination of equilibrium constants for EB-DNA bases have been performed to help explain the fluorescence enhancement. The results suggest that the excited state stabilization in the hydrophobic environment, the loss of torsional/vibrational energy of amino groups, and the change in the electronic transition characteristics are all responsible for the fluorescence enhancement.

• Bulletin of the Korean Chemical Society
• /
• v.20 no.6
• /
• pp.731-733
• /
• 1999

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.290.1-290.1
• /
• 2003

Oxidative DNA damage has been associated with many disease. Quantation of DNA adducts is considered to be a useful biomarker of oxidative DNA damage because its formation can also be induced by oxidative stress. Extensive efforts have been taken to identify the analytical methods for minimizing the artifactual formation of oxidative DNA damage. We have done direct analysis of DNA adducts using LC/ESI-MS without urine sample extraction. (omitted)