• Journal of Gastric Cancer
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• v.1 no.4
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• pp.221-227
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• 2001

Purpose: We have carried out prospective randomized clinical trial to compare survival benefit and side effect among three postoperative adjuvant chemotherapeutic regimens in serosa-negative gastric cancer patients. Materials and Methods: Total 317 cases were recognized as serosa negative and randomized into three groups at operating room. Out of them, 172 cases were excluded because of various reasons and 135 cases were analyzed finally; Group A 36 cases, Group B 49 cases, Group C 50 cases. Group A were treated with intravenous FP combination therapy, group B with MF combination therapy and group C with oral $UFT^{(R)}$ (mixture of Tegafur and Uracil) for one year. The median follow-up period was 30 months. Results: $88.9\%$ of Group A, $83.7\%$ of Group B and $90.4\%$ of Group C received adequate chemotherapy. The complication rates of Group A ($44.4\%$) was significantly higher than group B ($20.4\%$) and group C ($24.0\%$)(P<0.05). Most frequent complications were nausea and vomiting. The 3-year survival rates and disease-free survival rates were $92.2\%$ and $89.9\%$ respectively (Group A: $96.6\%,\;87.8\%$, B: $90.3\%,\;87.7\%$, C: $95.7\%,\;93.8\%$). There were no significant differences in survival rate and disease-free survival rate among the three groups (P>0.05). Conclusion: This study might suggest that the survival benefit of postoperative adjuvant chemotherapy for gastric Pseudomonas aeruginosa, and therefore it may be a useful adjunct tool for detection of Pseudomonas aeruginosa infection in combination with other conventional techniques.

• Parasites, Hosts and Diseases
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• v.28 no.2
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• pp.71-78
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• 1990

To assess the role of cAMP on the growth and proliferation of Toxoplasma in HL-60 cells we tested the effect of exogenous cAMP and cAMP analogues to the co-culture system of Toxoplasma and HL-60 cells. cAMP, dbcAMP, and br-cAMP stimulated the growth of Texoplasma at a specific concentration, i.e., 100 mM, l00 mM, and 10-1 mM, respectively. There were differences in growth induction kinetics and in the rate of promotion. These results were further verified by treating the co-culture with adenylate cyclase activator, pNHppG, cAMP phosphodiesterase activators, imidasole and A23187, and cAMP phosphodiesterase inhibitors, IBMX, compound 48/80, and theophylline, separately. When the cytosolic cAMP levels increased by the reagents mentioned above, Toxoplasma in the cytoplasm of HL-60 cells stimulated to proliferate more rapidly with concentration-dependent modes compared to the control, and vice versa. It is suggested that some mechanisms are activated by the high levels of cAMP in the cytoplasm, which result in the stimulation of Toxoplasma proliferation.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.176-180
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• 1989

There are three pseudourdine ($Psi$)bases in the E. coli $tRNA^{phe}$ In order to study the function of the pseudouridine bases in the $tRNA^{phe}$, changes of bases $tRNA^{phe}$ gene to other bases were undertaken by the site-specific mutagenesis. Site-specific mutagenesis of T in the pheW gene, a $tRNA^{phe}$ gene of E. coli, corresponding to the baseat the No.32 position to C and also T corresponding to the base at the No.39 position to C were performed using Kunkel's uracil-containing template method. Identification of mutants were undertaken by the KNA sequencing techniques of the mutated pheW genes and activities of the mutated pheW genes complementing to E. coli NP37 mutant($pheS^{-ts}$) using the recombinant plasmid containing the mutated genes. Neither NP37 harboring pheW gene mutated at No.32 position nor NP37 harboring pheW gene mutated at No.39 position can be grown at non-permissive temperature. The result means that both mutated pheW genes can not complement to E. coli NP37, and that the pseudouridine bases are essential to the activity of the E. coli $tRNA^{phe}$ in vivo.

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1248-1254
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• 2007

The secretory overexpression of Clostridium thermocellum endoglucanase A gene (celA) was examined in Saccharomyces cerevisiae using Kluyveromyces marxianus exoinulinase (INU1) signal sequence and GAL10 promoter. The two plasmids, pYEG-CT1 with its own signal sequence, and pYInu-CT1 with INU1 signal sequence were introduced to S. cerevisiae SEY2102 and S. cerevisiae 2805 host strains, respectively, and then each transformant was selected on the synthetic defined media lacking uracil. The expression level and secretion efficiency of endoglucanase A was increased by $18{\sim}22%$ and 11%, respectively, by INU1 signal sequence over celA signal sequence. By considering the high level of expression (361 unit/I), plasmid stability (89%), and secretion efficiency (70%), S. cerevisiae 2805 harboring plasmid pYInu-CT1 was selected as the opti-mal host vector system for the production of cellulose-degrading enzyme and recombinant yeast probiotic. The total expression and secretion efficiency of endoglucanase A was 418 unit/l and 73%, respectively, in the batch fermentation of S. cerevisiae 2805/pYlnu-CT1 on galactose medium. The mo-lecular weight of secreted endoglucanase A was found to be greater than 100 kDa, presumably due to the N-linked glycosylation.

• Journal of Aquaculture
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• v.8 no.3
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• pp.209-220
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• 1995

The nuclear matrix was isolated from Misgumus mizolepis liver nuclei by low salt extraction and restriction enzyme treatment. The structure was digested with proteinase K. After centrifugation, matrix attachment regions (MARs) were obtained by RNase treatment and phenol-chloroform extraction. The result leads to the appearance of smeared bands in the range of about 0.3-15 kb. pURY19 vector was constructed by inserting 2.13 kb Eco47 III fragment of the yeast uracil 3 gene into the unique Ssp I site of pUC19 plasmid vector as a selection marker. This vector is unable to be maintained in Sacrharomyces cerevisiae by itself since it cannot replicate as an extrachromosomal element. Using this system, we attempted cloning the ARS (autonomously replicating sequence) from M. mizelepis to develop an efficient expression vector for the transgenic fish. pURY19N_{l-62}$ were constructed by inserting MARs in pURY19 plasmid vector and transformation of E. coli $DH5\alpha$. Replication origins (ARS) of M. mizolepis were isolated, which enabled the vector to replicate autonomously in S. cerevisiae. The cloned DNA fragments were sequenced by Sanger's dideoxy-chain termination method. All clones were AT-rich. $pURY19N_6$, one of the clones, expecially contained ARS consensus sequence, Topoisomerase II consensus, near A-box and T-box.

• The Journal of Korean Society of Virology
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• v.30 no.1
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• pp.71-81
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• 2000

We have determined and analyzed the full-length cDNA sequence of a coxsackievirus B3 (CVB3) Korean isolate (CVB3-Korea/97) which has been known as a general human pathogen. The whole genome contains 7,400 nucleotides and has a single large open reading frame with 6,555 nucleotides that encodes a potential polyprotein precursor of 2,185 amino acids. The genome also contains a 5' non-coding region (NCR) of 741 bases and a 3' NCR of 104 bases followed by poly(A) tail. Sequence homologies of nucleotides and deduced amino acids between the CVB3-Korea/97 strain and the prototype (Nancy strain) were 81.7% and 91.5%, respectively. The genes encoding the functional proteins including viral protease and RNA dependent RNA polymerase showed higher homology than those encoding the structural proteins. We have further analyzed the sequences of 5' NCR, VP1 and VP2 of CVB3-Korea/97, which are known as cardiovirulent determining factors at the nucleotide and amino acid levels. Although the CVB 3-Korea/97 strain was isolated from an aseptic meningitis patient without cardiomyopathy, its 234th nucleotide and 165th amino acid were uracil and Asn as same as those of other cardiovirulent strains one. However, the 155th amino acid of VP1, which closely associated with cardiovirulence, was replaced with $Arg^{155}$ by single nucleotide substitution from $A^{2916}$ to $T^{2916}$. Moreover, additional amino acid substitutions were observed in the flanking region of $Asp^{155}$. Taken together, amino acid(s) substitution in VP1 may playa critical role in determining cardiovirulence of the CVB3-Korea/97 strain rather than individual nucleotide replacements in the 5' NCR and/or an amino acid substitution in VP2.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.103-110
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• 2003

The regulation of pyrimidine nucleotide synthesis has been proved to be controlled by a regulatory protein PyrR-mediated attenuation in the Gram-positive bacteria. After several bacterial genome sequencing projects, we have discovered the PyrR orthologues in the databases for Haemophilus influenzae and Synechocystis and sp. PCC6803 genome sequences. To investigate whether these PyrR orthologue proteins regulate pyrimidine nucleotide synthesis as well as the cases of Bacillus, the PyrR regions of each strains were amplified by PCR and cloned with pUC19 or T-vector in Escherichia coli and with a shuttle vector pHPS9 for E. coli and B. subtilis. For the regulation test of the PyrR orthologues, the aspartate-transcarbamylase (ATCase) assay was carried out. From the results of the ATCase assay, it was confirmed that Synechocystis sp. PCC6803 could not restore by pyrimidines to a B. subtilis, PyrR but H. influenzae PyrR could. For Purification of PyrR orthologue proteins, PyrR orthologue genes were cloned into the expression vector (pET14b). Over-expressed product of PyrR orthologue genes was purified and analyzed by the SDS-PACE. The purified PyrR orthologue proteins from H. influenzae and Synechocystis sp. PCC6803 turned out to be molecular mass of 18 kDa and 21 kDa, respectively. The result of uracil phosphoribosyl transferase (UPRTase) assay with purified PyrR orthologue proteins showed that H. influenzae PyrR protein only has UPRTase activity. In addition, we could predict several regulatory mechanisms that PyrR orthologue proteins regulate pyrimidine de novo synthesis in bacteria, through phylogenetic analysis for PyrR orthologue protein sequences.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.285-291
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• 2014

Saflufenacil is a low-volatile and uracil-based herbicide. This herbicide is used for pre-and post-emergence control of major broadleaf weeds. The objective of present study was to develop and validate an analytical method for saflufenacil determination in agricultural products for ensuring the food safety. The saflufenacil residues in samples were extracted with acetone, dichloromethane, and then purified with silica and graphitized carbon cartridge. The purified samples were analyzed by HPLC-UVD and confirmed with LC-MS. The linear range of saflufenacil was $0.1{\sim}5.0{\mu}gmL^{-1}$ with the correlation coefficient (r) = 0.999. Average recoveries of saflufenacil ranged from 80.5% to 110.2% at the spiked level of $0.02{\sim}0.5mgkg^{-1}$, while the relative standard deviation was 0.3~7.3%. In addition, the limit of detection and limit of quantification were 0.005 and $0.02mgL^{-1}$, respectively. Furthermore, an interlaboratory study among three labs was conducted to validate the method, and the results were satisfactory.

• Korean Journal of Heritage: History & Science
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• v.40
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• pp.387-411
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• 2007

The analysis of ancient DNA (aDNA) has become increasingly considerable anthropological, archaeological, biological and public interest. Although this approach is complicated by the natural damage and exogenous contamination of a DNA, archaeologists and biologists have attempted to understand issues such as human evolutionary history, migration and social organization, funeral custom and disease, and even evolutionary phylogeny of extinct animals. Polymerase chain reaction(PCR) is powerful technique that analyzes DNA sequences from a little extract of an ancient specimen. However, deamination and fragmentation are common molecular damages of aDNA and cause enzymatic inhibition in PCR for DNA amplification. Besides, the deamination of a cytosine residue yielded an uracil residue in the ancient template, and results in the misincorporation of an adenine residue in PCR. This promotes a consistent substitution (cytosine thymine, guanine adenine) to original nucleotide sequences. Contamination with exogenous DNA is a major problem in aDNA analysis, and causes oversight as erroneous conclusion. This report represents serious problems that DNA modification and contamination are the main issues in result validation of aDNA analysis. Now, we introduce several criterions suggested to authenticate reliance of aDNA analysis by many researchers in this field.

• The Korean Journal of Mycology
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• v.6 no.2
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• pp.1-10
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• 1978

In de novo biosynthesis of the extracellulor enzymes-proteinsaes, alpha and gluc-amylases during the synchronized differentiation of Aspergillus niger in submerged culture and surface liquid culture were investigated. Gluc-amylase was synthesized in the stage of presporulation in which phialide formation is involved. Proteinase was synthesized both in the stages of conidiophore formation and presporulation. Alpha-amylase was synthesized during presporulation and sporulation stages, the activity of enzyme lasted for seven days on surface liquid culture. It seemed that the synthesis was occured in de novo partly repressed by the catabolite, and its nature was found to be constitutive since it is produced in non-starch medium. Polyacrylamide gel electrophoresis have shown that presporulating and sporulating body produced diverse types of the proteins whereas the earlier stages of vegetative body showed simpler profiles. The uptake of C-14 uracil into RNA and C-14 glutamate into protein were shown to be vigorous in presporulating body rather than those in sporulating body. Coincidence of alpha-amylase biosynthesis in de novo and sporulation may be significant in the study of differentiation in which gene expression is involved.