• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.545-552
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• 2005

The major protocol features of the rodent uterotrophic assay have been evaluated using a range of reference chemicals. The protocol variables considered include the selection of the test species and route of chemical administration, the age of the test animals, the maintenance diet used, and the specificity of the assay for estrogens. The rodents were ovariectomized under general anesthesia via bilateral flank incisions and randomly assigned to groups of 5 animals. Chemicals were DEHP, DBP, BPA and NP, were injected sc once daily with combinations of chemicals treatments for 3 days. In the results, the reported estrogenic chemicals DEHP and DBP were both negative in the single dose treatments. But, in the combinations of chemicals treatments, DEHP and DBP increased in bud number of mammary gland. Treatment of ovariectomized mice with combinations of other chemicals resulted in uterine and vaginal hyperplasia. The additive estrogenic effects were seen with the combinations of $17{\beta}$-Bestradiol and DBP treatment. the competitive estrogenic effects were seen with the combinations of $17{\beta}$-Bestradiol and nonylphenol, $17{\beta}$-Bestradiol and bisphenol-A treatments. These results offers a sysmatic and mechanistically informative approach to assessing estrogenicity. it provides a useful profile of activity using a reasonable amount of resources and is compatible with the study of individual chemicals as well as the investigation of interactions among combinations of chemicals. The results described illustrate the intrinsic complexity of evaluating chemicals for estrogenic activities and conform the need for rigorous attention to experimental design and criteria for assessing estrogenic activity.

• Journal of Pharmaceutical Investigation
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• v.17 no.3
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• pp.111-126
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• 1987

Methyl methacrylate-butyl methacrylate copolymer (MMBM)-dibutyl phthalate (DBP) films were investigated as a potential topical drug delivery system for the controlled release of nitrofurazone. The kinetic analysis of release data indicated that drug release followed a diffusion-controlled granular matrix model, where the quantity released per unit area is proportional to the square root of time. DBP of several hydrophobic plasticizers selected was found to give the highest release of nitrofurazone. However, hydrophilic plasticizers such as propylene glycol and polyethylene glycol 400 had no controlled release properties and acceptable film formation. The effects of changes in film composition, drug concentration, film thickness, pH of release medium, and temperature on the in vitro release of nitrofurazone were analyzed both theoretically and experimentally. The release rate constant (k') was found to be proportional to DBP content, pH, and the temperature of release medium, but independent of film thickness, and drug concentration in a range of 0.1-0.4% by weight. The linear relationship was found to exist between the log k' and DBP content. The release of nitrofurazone from MMBM-DBP (8:2) films was found to be an energy-linked process. Two energy terms were calculated ; the activation energy for matrix diffusion was 13.45 kcal/mole, and the heat of drug crystal solvation was 27.26-29.34 kcal/mole. Observation of scanning electron micrographs and microscopic photographs showed that the incorporation of DBP in films increased markedly the particle size of nitrofurazone dispersed in the film matrix, comparing with the fine dispersion of nitrofurazone in pure MMBM film alone.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.209-212
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• 2007

To evaluate the estrogenic activities of di-ethyl hexyl phthalate (DEHP) and di-butyl phthalate (DBP), two phthalates known as endocrine disrupters, we used MCF-7 human breast cancer cell line. As results, DBP and DEHP had estrogenic effects. In brief, the concentration of maximal MCF-7 cell proliferation was $10^{-7}M\;and\;10^{-8}M$ for DEHP and DBP, respectively. The ratio of maximal cell yield of the test compounds to that of $17{\beta}-estradiol$ was 87.5% for DEHP and 73.4% for DBP. In summary, both DEHP and DBP had cell proliferation potencies in the MCF-7 cell. Potencies ranged from approximately 10 to 100 times less than 17beta-estradiol. DBP was stronger than DEHP in the concentration of maximal efficacy. However, DEHP was stronger than DBP in the MCF-7 cell proliferation. Results from this study suggested that DEHP and DBP may play an important role in the estrogenic activity. Therefore, it is suggested that DEHP and DBP are estrogenic.

• Membrane and Water Treatment
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• v.4 no.4
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• pp.277-291
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• 2013

The transport and recovery of Levafix brilliant red E-4BA and Levafix brilliant red E-6BA were investigated using polytetrafluoroethylene (PTFE) fiber based supported liquid membrane containing tetra butyl ammonium bromide (TBAB) in coconut oil as a carrier. The influencing parameters studied are: pH of the feed solution, concentration of dye in the feed solution, extractant concentration, and various kind of stripping agent, rate of stirring, time of transport, reusability of membrane and stability of membrane. Increase in TBAB concentration inside the membrane enhances the flux with its maximum value at $1.553{\times}10^{-4}$ M TBAB. Further increase in the concentration of TBAB leads to decreased rate of transport due to increase in viscosity of membrane liquid. The optimum conditions for dye transport are: pH of feed ($7{\pm}0.1$), $1.553{\times}10^{-4}$ M extractant concentration, 350 rpm for stirring, $4.9{\times}10^{-1}$ M potassium hydrogen phthalate as a stripping solution, the time of transport 6 h. It was noticed that flux values were increased with increasing dye concentration in the feed phase. Applying this study to textile wastewater, dyes were transported up to 98% in 6 h. This recovery technique is rewarding to environment and economic.

• Bulletin of the Korean Chemical Society
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• v.24 no.12
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• pp.1793-1798
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• 2003

A series of amorphous molecules that possess both photoconductive and electro-optic properties was synthesized in order to investigate photorefractive properties of bifunctional organic-glasses. Diethylaminobenzaldehyde-diphenylhydrazone was covalently attached to 5-(4-diethylamino-benzylidene)-1,3-dimethylpyrimidine-2,4,6-trione through a flexible alkyl chain (3, 4, 5, 6 and 10 carbons) containing two ether linkages. The longer linkage not only lowered the glass transition temperature ($T_g$) of the molecules, but also allowed faster orientation of the chromophore. To examine the photorefractive properties, a 50 ${\mu}$m-thick film was prepared from the mixture of a bifunctional molecule, butyl benzyl phthalate, and $C_{60}$. The photoconductivity of this composite was as high as $8.01\;{\times}\;10^{-12}$ S/cm at 60 V/ ${\mu}$m, and the maximum diffraction efficiency ( ${\eta}_{max}$) of 50 ${\mu}$m-thick film was about 5% at 80 V/ ${\mu}$m.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.218-222
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• 2007

Di(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) were screened for estrogenic activity using a recombinant yeast screening system consisted with estrogen receptors and ${\beta}-galactosidase$ as reporter gene. The chemicals showed estrogenic activity in ranges of $1{\times}10^{-10}\;to\;1{\times}10^{-7}M(DEHP)\;and\;of\;1{\times}10^{-9}M\;to\;1{\times}10^{-6}M(DBP)$ respectively. $17{\beta}-estradiol$, as a positive control of, showed maximal activity at $1{\times}10^{-9}M$. The concentration of half-maximal estrogenic activity was $1{\times}10^{-9}M$ for both chemicals. However, the concentration of maximal estrogenic activity was $1{\times}10^{-7}M$ for DEHP and $1{\times}10^{-8}M$ M for DBP. These results suggested that DBP was higher in relative potencies and more sensitive than DEHP. In conclusion, DEHP and DBP were both estrogenic, even though DBP was more reactive to estrogen receptor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.881-885
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• 2006

The product formation and changes in color of glucose/glutamine model system were investigated in relation to heating temperature and time. The mixtures of glucose and glutamine in equal molar ratio were heated at 125, 150 and $175^{\circ}C$ for 10, 20 and 30 minute, respectively. Acetic acid, butanoic acid, 2-butenoic acid, di-(2-cthylhexyl)phthalate, 2,3-dihydro-3,5-dihydroxy-6-methly-4H-pyran-4-one and 5-hydroxymethylfurfural were identified as a major compounds, and 1,3-dimethylbenzene, 2-ethylhexanol, furfural, 5-methylfurfural, 2-pyrrolidinone, and 2,6-di(t-butyl)-4-hydroxy-4-methyl-2.5-cyclohexadien-1-one as 6 minor compounds by using GC/MS. The contents of acetic acid, 2-ehylhexanol and 2-pyrrolidinone increased with increased heating temperature and time, whereas the formation of the other 9 compounds increased up th heating conditions of $150^{\circ}C$ for 10 or 20 min or $175^{\circ}C$ for 10 min, and decreased dramatically with heating above those conditions. Color parameter $L^*$ decreased with increasing heating conition, resulting in dark brown color in final products. Changes of redness parameter $a^*$ and yellowness $b^*$ showed similar to those of the contents of 9 compounds mentioned as above.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.931-937
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• 1999

Styrene dimers and trimers from polystyrene cup noodle containers were analyzed by GC and GC/MS extracted with various simulants. For the quantitation of styrene dimers and trimers, 1,3-diphenylpropane (DP) and benzyln-butyl phthalate (BBP) were chosen as the standards. The results showed that the average of the styrene dimers in the containers was 603 ppm, and that of trimers was 5731 ppm. Four styrene dimers, including 1,2-diphenyl-cyclobutane, were identified as well as seven trimers such as 2,4,6-triphenyl-l-hexene. The migration of the styrene dimers and trimers, from the cup noodle containers of polystyrene into foods, was conducted using simulants including boiling water as well as soybean oil and n-heptane. In addition to, the analysis of each migrated styrene was also performed filled with boiling water into noodle and soup after certain time (5, 10, 20, 30 min). The results showed that the migration of styrene dimers and trimers from cup noodle containers was not detected in the case of using boiled water or soybean oil as a simulant, while styrene dimers and trimers were detected 1.18 ppm and 14.21 ppm, respectively, when heptane was adopted as a simulant. In the case of filling with boiled water into noodle and soup, both styrenes were not detected at 5 min and 10 min, however, some samples standing for 20 min released styrene dimers and trimers as much as 0.009 ppm, and 0.019 ppm for 30 min.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.185-187
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• 2004

The co-administration of BPA and BBP induced slow weight gain compared with single administration in dams. Also, such mixture induced low neonatal body weights in next generation. The dams treated with BPA and BBP showed significant organ weight changes in liver, spleen exposed during lactational periods. But the dams exposed during lactational periods showed significant organ weight changes not only in liver, spleen but also in kidney, uterus and ovary. The F1 female rats exposed during lactation periods showed significant organ weight changes in liver, spleen, ovary. The F1 male rats showed significant organ weight changes in liver, kidney, epididymis, vesicular glands, prostate. However no clear synergistic effects of BPA and BBP could be found. Estrogen receptor ${\alpha}$ expression by BPA and BBP in the uterus(dam, F1 female) and testis(F1 male) were studied. There was no significant different $ER{\alpha}$ expression pattern between control and treated groups. But $ER{\alpha}$ expression were increased in F1 male testis and female uterus. F1 male showed distinct $ER{\alpha}$ expression, especially in the group of lactational combined exposure. Synergistic $ER{\alpha}$ expression was found by combined treatment of BPA and BBP.

• Environmental Mutagens and Carcinogens
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• v.24 no.1
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• pp.40-45
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• 2004

In order to understand the mechanism of the regulation of drug metabolizing enzyme gene expression, we have studied the induction of CYP1A1 and GSTα, μ, π enzymes in Japanese monkey and rhesus monkey after the treatment with 3-methylcholanthrene (3MC) and di-n- butyl phthalate (DBP) and bisphenol A (BPA). The levels of mRNA were measured_by RT-PCR in brain, intestine and liver. In the case of adult monkey, treatment with 3MC induced CYP1A1 mRNA in brain by 2-fold. The treatment with DBP induced CYP1A1 mRNA. Effects of 3MC and DBP on GST mRNA expression was not clear. But GSTμ was slightly inhibited by the treatment with 3MC and DBP. GSTα was not induced by the treatment with 3MC and DBP in brain. GSTπ was slightly induced by the treatment with 3MC and DBP in brain. In the case of fetus monkey, the basal levels of fetus CYP1A1 mRNA and GSTs mRNA were relatively low compared to adult monkey. As the age of monkey increased, the basal levels of CYP1A1 mRNA were also increased. 3MC induced the expression of CYP1A1 mRNA in liver, whereas it didn't significantly induce CYP1A1 mRNA in brain. The levels of GSTμ and GSTα were not changed by the treatment with 3MC and DBP. GSTπ was slightly induced by the treatment with 3MC and DBP.