• Bulletin of the Korean Mathematical Society
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• v.41 no.3
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• pp.413-418
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• 2004

Invertible and isometric composition operators acting on vector-valued Hardy space $H^2$(E) are characterized.

• YAKHAK HOEJI
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• v.55 no.1
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• pp.75-79
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• 2011

The replication competent adenoviral vector (AV), AdLPCDIRESE1A was generated and reported previously to have cytotoxic effects in some cell lines. In AdLPCDIRESE1A, the expression of cytosine deaminse (CD) and E1A genes are under the control of tumor-specific L-plastin promoter. CD enzyme can deaminate the nontoxic prodrug 5-fluorocytosine (5-FC) to the toxic 5-fluorouracil (5-FU). E1A gene is essential for viral replication. Primary liver cancer, most of which is hepatocellular carcinoma (HCC), is the third common leading cancer in Korea. Thus, we have conducted in vitro preclinical study to evaluate effectiveness of AdLPCDIRESE1A on HCC. The efficacy of cytotoxicity was measured by generation of cytopathic effect (CPE) and cell counting. We infected HepG2 cells with various MOI of vector alone or concurrent with 5-FC. Exposure of cells to AdLPCDIRESE1A generated a significant cytotoxic effect as compared to the control. Almost 83% of the cell had manifested the characteristic cytotoxic effect on day 9 after infection of cells with 10 MOI of vector. We also observed the additive cytotoxic effects when AdLPCDIRESE1A vector had been coadministrated with 5-FC. The results suggest that the use of AdLPCDIRESE1A/5FC may be value in treatment of liver cancer. Further animal studies are needed for clinical trial.

• Microbiology and Biotechnology Letters
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• v.15 no.5
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• pp.319-327
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• 1987

In order to develop useful plasmid vectors for Zymomonas cells, attempts were made to isolate natural plasmids from Z. mobilis ATCC10988. Among a few plasmids isolated, a small plasmid of 3.9 Kb size was chosen and designated as pZM3. By introducing the replication origin of pZM3 into pBR325, a hybrid plasmid vector of 8.4 Kb size, pHZ22, was constructed. This vector contained chloramphenicol resistant gene as a selectable marker and proved to be conjugally transmissible and stably maintained in Z. mobilis. Tetracycline resistant gene was isolated from RP4 and introduced into pHZ22 to make a new vector called pHZT224 of 10.7 Kb size. Through n series of experiments, it was evident that these plasmid vectors containing selectable markers of chloramphenicol and tetracycline resistance were shuttle vectors functional in Z. mobilis as well as E. coli.

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.249-255
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• 1984

To develop the host-vector system for industrial Coryneform bacteria that seemed to be the most suitable microorganisms for molecular breeding of genes involved in the production of amion acids, nucleotides, and other products of industrial interest, broad host range E. coli plasmid R 1162 DNA was transformed into Brevibacterium ammoniagenes and the plasmids pKU6 isolated from a transformant was physically characterized. All other plasmids from the transformed cells except pKU6 exsisted as multimeric forms in Brevibacterium ammoniagenes. The plasmid DNA was retransformed into Corynebacterium glutamicum with a high frequency ($1.32{\times}10^{-1}$ per cell) and maintained stably both in Brevibacterium ammoniagenes and Corynebacterium glutamicum after 100 generations of cultures with 25-30 copy number per cell. The size of both plasmid pKU6 and plasmid R1162 were the same and restriction maps by EcoR I, Ava I, Pst I, Pvu II and Hinc II were also similar.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.592-595
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• 2009

We propose an automatic spam mail classifier for e-mail data using Support Vector Machines (SVM). We use a lexical form of a word and its part of speech (POS) tags as features. We select useful features with ${\chi}^2$ statistics and represent each feature using text frequency (TF) and inversed document frequency (IDF) values for each feature. After training SVM with the features, SVM classifies each email as spam mail or not. In experiment, we acquired 82.7% of accuracy with e-mail data collected from a web mail system.

• Korean Journal of Microbiology
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• v.30 no.1
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• pp.60-64
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• 1992

The secretion vector with promoter and signal sequence region of neutral protease gene (npr) from Bacillus amyloliquefaciens was constructed by the technique of polymerase chain reaction (PCR). A unique restriction iste was introduced into the 3' of the signal coding region by the synthesis of PCR primer. To demonstrate the function of cloned promoter and signal sequence, we used the E. coli .betha.-lactamase structural gene as a foreign gene. The signal sequence of .betha.-lactamase gene was deleted by Bal31 exonuclease and only mature region was introduced into the secretion vector. Bacillus subtilis cells transformed by the recombinant vector synthesized the fusion protein and were also capable of removing the signal peptide from the original fusion protein, as judged by the assay of .betha.-lactamase activity and secretion into the growth medium by western blotting.

• Journal of the Chungcheong Mathematical Society
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• v.26 no.4
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• pp.853-867
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• 2013

In this paper we study the cardinality of the dot product set generated by two subsets of vector spaces over finite fields. We notice that the results on the dot product problems for one set can be simply extended to two sets. Let E and F be subsets of the d-dimensional vector space $\mathbb{F}^d_q$ over a finite field $\mathbb{F}_q$ with q elements. As a new result, we prove that if E and F are subsets of the paraboloid and ${\mid}E{\parallel}F{\mid}{\geq}Cq^d$ for some large C > 1, then ${\mid}{\Pi}(E,F){\mid}{\geq}cq$ for some 0 < c < 1. In particular, we find a connection between the size of the dot product set and the number of lines through both the origin and a nonzero point in the given set E. As an application of this observation, we obtain more sharpened results on the generalized dot product set problems. The discrete Fourier analysis and geometrical observation play a crucial role in proving our results.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.305-308
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• 1990

In order to clone the gene coding for 3-isopropylmalate dehydrogenase of Muyveromyces fragilis, a shuttle plasmid vector pHNll4 was used. It can serve as a cloning vector in Saccharomyces cerevisiae DBY746 for other Sau3AI-cleaved DNA segment of Kluyveromyces fragilis. Two cloned fragments which complement the leu2 mutation of Saccharomyces cerevisiae and E, coli were obtained. Their length was 4.4 kb an 3.5 kb, and their orientation was opposite each other. From the fact that the two recombinant plasmids were expressed in Saccharomyces cerevisiae and E, coli, probably the two inserts had the promoter of Ktuyveromyces fi-agilis and that of Kluyveromyces fiagilis was efficiently assosiated with RNA polymerase of Saccharomyces cerevisiae and E. coli. According to the result of Southern hybridization, we thought that the cloned fragment has low homology with 3-isopropylmalate dehydrogenase coding region of E. coli and Saccharomyces cerevisiae.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.171-175
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• 2003

The putative endochitinase gene, yheB of Escherichia coli K-12 is not expressed under lab culture conditions. The endochitinase gene was amplified by PCR and subcloned into pET28c vector and pQE9 vector, respectively. The endochitinase produced in E. coli harboring pET28c containing yheB or pQE9 vector containing yheE was partly released into the growth medium. The overproduced endochitinase was partially purified by His affinity column chromatography and DE-52 column chromatography. The apparent molecular weight of the endochitinase determined by SDS-polyacrylamide gel electrophoresis was about 97,000. The purified E. coli endochitinase showed maximal chitinolytic activity at pH 6 and $40^{\circ}C$.

• Korean Journal of Animal Reproduction
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• v.19 no.1
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• pp.35-41
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• 1995

In this study, we have tested whether the retrovirus vector system is applicable in transgenic cattle production. To overcome low infectivity of currently available retrovirus vector system we have directly microinjected retrovirus-producing cells into the perivitelline space of the day 1.5 embryos. The virus-producing cell line was designed to release replication-defective retrovirus encapsidated with Gibbon ape leukemia virus (GaLV) envelope protein. E. coli LacZ gene was used as a marker gene to facilitate evaluation of the transgene expression and X-gal staining at morula or blastocyst stage resulted in expression of E. coli LacZ gene The results in these experiments were summarized as follows : 1. The lowest concentration of polybrene necessary for efficient virus infection was Sf' g/ml. 2. Development rate from day 1.5 embryos microinjected with virus-producing cells to the morulae /blastocysts was 29%. 3. 21% of the morulae /blastocysts were LacZ+. 4. There was no evidence that the retrovirus-producing cells used in this study produced replication-competent retrovirus.