• Nutrition Research and Practice
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• v.2 no.4
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• pp.234-239
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• 2008

The purpose of this study was to investigate the effects of green tea ingestion on hepatocarcinogenesis before and after its initiation. Male Sprague-Dawley rats were fed an AIN76A diet with or without green tea. Initiation was induced by a single dose (200 mg/kg) of diethylnitrosamine at week 4 and 0.02% (w/w) 2-acetylaminofluorene was supplied in the diets. The control group had free access to water for 13 weeks (CTR13). Tea infusion was provided from the beginning of the experiment for 13 weeks (PRE13) or from the post-initiation stage until week 13 (POST13). Three other groups (CTR24, PRE24 and POST24) were added to examine the longer-term effects (24 weeks) with the same experimental design. The percentage area of liver sections that were positive for hepatic placental glutathione S-transferase (GST-P), which was used as a marker of preneoplastic lesions, was smaller in PRE13 ($20.2{\pm}5.0%$, $mean{\pm}SD$) and POST13 ($26.0{\pm}4.8%$) than in CTR13 ($33.2{\pm}5.8%$, p<0.05). Over the longer period, the GST-P lesions were significantly smaller for both PRE24 and POST24 ($21.6{\pm}8.5%$ and $22.2{\pm}4.0%$, respectively) than for CTR24 ($28.6{\pm}5.1%$, p<0.05), but there was no significant difference between PRE24 and POST24. The liver content of thiobarbituric acid reactive substances was significantly lower in the tea groups than in the controls (p<0.05). However, no significant differences were observed among groups of GST activity. The results show that tea consumption exhibits a stronger short-term initiation-inhibiting ability in liver carcinogenesis, but over a longer period, the preventive effects of green tea ingestion do not differ in post- and pre-initiation.

• Honam Mathematical Journal
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• v.31 no.3
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• pp.437-449
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• 2009

In this paper, we calculate the number of points on elliptic curves $E^{a^3}_0:y^2=x^3+a^3$ over ${\mathbb{F}}_p$ mod 24 and $E^b_0:y^2=x^3+b$ over ${\mathbb{F}}_p$ mod 6, where b is cubic non-residue in ${\mathbb{F}}^*_p$. For example, if p ${\equiv}$ 1 (mod 12) is a prime, and a and a(2t - 3) are quadratic residues modulo p with $3t^2{\equiv}1$ (mod p), then the number of points in $E^{a^3}_0:y^2=x^3+a^3$ is congruent to 0 modulo 24.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.177-187
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• 2011

This study was performed to evaluate the polymers and surfactants as the potential control agents of sweet potato whitefly Bemisia tabaci, which is causing problems in ornamental garden and greenhouse. Polymers have an insecticidal activity to knock down and to be lethal to small winged insects by its viscosity. Among five polymers tested at 0.2% concentration, polinol P-24 showed the highest insecticidal activity as 59.4% against B. tabaci adult in cylindrical chamber, and followed by polinol P-20 (insecticidal activity, 57.1%). When treated at 0.1 % or 0.3% concentrations, Polinol P-24 also showed the highest insecticidal activity with 43.3% and 54.5%, respectively. Among eight surfactants tested, insecticidal activity was the highest in 0.0005% NP10 treatment (70.0%), and followed by 0.001% NP7 (67.4%). The synergistic effect between polinol P-24 and eight surfactants was evaluated. After bioassays, the 0.2% polinol P-24 plus 0.005% NP10 was selected as a candidate control agent for controlling of B. tabaci adults. Polinol P-24/NP10 was showed the highest control efficacy against B. tabaci adults applied three times at three day-intervals in square rearing cage. In the greenhouse, the mixture treatment showed good control value over 70% seven days after treatment.

• Childhood Kidney Diseases
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• v.4 no.1
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• pp.1-5
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• 2000

Purpose: The plcr of spot urine has been uised to predict the timed urine protein excretion. Although this method reduces errors caused by variations in urine volume, it is relatively thconvenient and expensive. Recently, a more rapid and less expensive screening method with specific gravity(SG) has been reported, and we have examined whether estimated-creatinine(Cr-est) with urine 5G could be used in place of urine creatinine to predict 24-hour collected urine protein excretion in children. Methods: We had retrospectively analyzed protein, creatinine and urine SG in randomized spot urine samples of 147 patients from March 1998 till June 1998 in Korea university Guro hospital and compared the urinary protein creatinine ratio(P/Cr) with the protein estimated-creatinine ratio(P/Cr-est). We compared the correlation of urinary creatinine vs-urine 5G with the timed urine pretein excretion. Results: 1) urine SG accurately estimated urine creatinine concentration (r=0.407, P<0.001, Cr=SG x 4485.82-4482.87). 2) P/Cr correlated with urine protein excretion measured in a 24-hour urine collection (r=0.771, P<0.001, 24-hour collected urine protein : 0.338 x (P/Cr) 4+667.885). 3) P/Cr-est correlated with a 24-hour collected urine protein (r=0.723, P<0.001, 24-hour collected urine protein =0.354 x (P/Cr-est)+726.044), Conclusions: These results suggest that P/Cr-est with urine SG could be useful method for screening proteinuria in children.

• Journal of Microbiology and Biotechnology
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• v.13 no.5
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• pp.660-665
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• 2003

High-level expression of Thermus caldophilus GK24 alkaline phosphatase (Tca APase) was achieved in Escherichia coli using the pET-based expression plasmids, pEAP1 and pEAP2. In the case of plasmid pEAP2, the signal peptide region of Tca APase was replaced by the PelB leader peptide of expression vector pET-22b(+). Furthermore, the expression level was somewhat higher than that of plasmid pEAPl. A rapid purification procedure of Tca APase overproduced in E. coli was developed which involved heating to denature E. coli proteins followed by HiTrap Heparin HP column chromatography. Optimal temperature and pH and $Mg^{2+}$ dependence of the recombinant Tca APase were similar to those of native enzyme isolated from T. caldophilus GK24.

• Journal of Chest Surgery
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• v.30 no.9
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• pp.914-919
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• 1997

We analyzed the changes of pulmonary function after decortication i 33 patients with chronic empyema thoracis. In 11 patients of them, scintigraphic lung perfusion scan were performed. The results are as follows; 1, Forced expiratory volume in one second(FEVI) increased from 2.30 L/sec to 2.65 L/sec after decorticati on (p = 0.008) . 2. In patients under 20 years-old, PEV 1 increased significantly(p=0.001). 3. In patients who had tuberculosis empyema thoracis, FEVI increased significantly(p=0.008). The post-operative FEVI increased significantly 24 months later(p=0.013). 4. Te post-operative FEV1 increased significantly 24 months later(p=0013). 5. Perfusion and FEV1 of diseased lung changed from 21.5% to 26.9%(p=0.046) and 0.56 L/sec to 0.78 L/sec(p=0.071) after decortication respectively and perfusion of non-diseased lung changed 78.4% to 72.9% after decortication(p=0.042).

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.7 no.2
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• pp.163-169
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• 2004

Purpose: Many diagnostic modalities have been used for diagnosis of gastroesophageal reflux disease (GERD). Feeding materials during esophageal pH monitoring may interfere the result of examination and esophageal pH monitoring can not diagnose GER in case of alkaline reflux. The purpose of our study is to evaluate whether scintigraphy can substitiute 24 hr pH monitoring in children with GERD. Methods: From March 2002 to June 2003, 23 patients (12 boys and 11 girls, mean age 27 months) who have been admitted to Hanyang University Hospital presented with GER symptoms (recurrent vomiting, cough, chest pain, irritability) were included in the study. Scintigraphy and 24 hr pH monitoring were performed in all patients. Results: Six out of the 23 patients (26.1%) had evidence of GER on 24 hr pH monitoring, whereas nine of 23 patients (39.2%) exhibited GER by scintigraphy. Two out of the 23 patients could not be tested because of irritability. Three (14.3%) patients had evidence of GER on both 24 hr pH monitoring and scintigraphy, three (14.3%) patients on only 24 hr pH monitoring, six (28.6%) patients on only scintigraphy, and nine (42.9%) patients had no evidence of GER on both methods. No correlation was observed between 24 hr pH monitoring and scintigraphic results by Fisher's exact test (p=0.523) or Kendal's tau (t=0.678). Conclusion: The results of this study demonstrated that there was no correlation between 24 hr pH monitoring and scintigraphy. Therefore these modalities could be used as complementary tests to diagnose GERD.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1215-1218
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• 2003

An analysis of the bonding situation in CaM₂P₂ (M=Fe, Ni) with ThCr₂Si₂ structure is made in terms of DOS and COOP plots. The main contributions to covalent bonding are due to M-P and P-P interactions in both compounds. Particularly, the interlayer P-P bonding by variation in the transition metal is examined in more detail. It turns out that the shorter P-P bonds in CaNi₂P₂ form as a result of the decreasing electron delocalization into ${{\sigma}_p}^*$ of P₂ due to the weaker bonding interaction between the metal d and ${{\sigma}_p}^*$ as the metal d band is falling from Fe to Ni.

• Microbiology and Biotechnology Letters
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• v.14 no.3
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• pp.213-218
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• 1986

Hybrid plasmid pEA24, shuttle vector YRp7 carrying amylase gene of Bacillus amyloliquefaciens, was transformed to yeast Saccharomyces cerevisiae, and the expression of B. amyloliquefaciens amylase gene in yeast was investigated. The frequency of transformation to S. cerevisiae DBY747 with YRp7 was increased by treatment of 40% polyethylene glycol (MW 4, 000), PH 7.0, at 3$0^{\circ}C$, and by regeneration used 2% top agar. The amount of cellular amylase activity produced by S. cerevisiae containing pEA24 was 2% of that secreted from B. amyloliquefaciens, but in case of S. cerevisiae transformant, the amylase secreted was not detected. A comparison of genetic stability of pEA24 and YRp7 plasmids in yeast was carried out by cultivation of transformants in tryptophan-supplement-medium. The pEA24 plasmid was more unstable than YRp7 in S. cerevisiae. The size of pEA24 extracted from S. cerevisiae transformants was found to be identical with that from E. coli transformants by agarose gel electrophoresis.

• Journal of Life Science
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• v.16 no.4
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• pp.589-597
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• 2006

Genistein, a natural isoflavonoid phytoestrogen, is a strong inhibitor of protein tyrosine kinase and DNA topoisomerase activities. There are several studies documenting molecular alterations leading to cell cycle arrest and induction of apoptosis by genistein as a chemopreventive agent in a variety of cancer cell lines; however, its mechanism of action and its molecular targets on human bladder carcinoma and leukemic cells remain unclear. In the present study, we have addressed the mechanism of action by which genistein suppressed the proliferation of T24 bladder carcinoma and U937 leukemic cells. Genistein significantly inhibited the cell growth and induced morphological changes, and induced the G2/M arrest of the cell cycle in both T24 and U937 cells with a relatively stronger cytotoxicity in U937. The G2/M arrest in T24 cells was associated with the inhibition of cyclin A, cyclin B1 and Cdc25C protein expression without alteration of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21(WAF1/CIP1). However, the inhibitory effects of genistein on the cell growth of U937 cells were connected with a marked inhibition of cyclin B1 and an induction of Cdk inhibitor p21 proteins by p53-independent manner. These data suggest that genistein may exert a strong anticancer effect and additional studies will be needed to evaluate the different mechanisms between T24 and U937 cells.