• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3767-3772
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• 2014

Introduction: MicroRNAs have emerged as post-transcriptional regulators that are critically involved in tumorigenesis. This study was designed to explore the effect of miRNA 133b on the proliferation and expression of TBPL1 in colon cancer cells. Methods: Human colon cancer SW-620 cells and human colon adenocarcinoma HT-29 cells were cultured. MiRNA 133b mimcs, miRNA 133b inhibitors, siRNA for TBPL1 and scrambled control were synthesized and transfected into cells. MiR-133b levels in cells and CRC tumor tissue was measured by real-time PCR. TBPL1 mRNA was detected by RT-PCR. Cell proliferation was studied with MTT assay. Western blotting was applied to detect TBPL1 protein levels. Luciferase assays were conducted using a pGL3-promoter vector cloned with full length of 3'UTR of human TBPL1 or 3'UTR with mutant sequence of miR-133b target site in order to confirm if the putative binding site is responsible for the negative regulation of TBPL1 by miR-133b. Results: Real time PCR results showed that miRNA 133b was lower in CRC tissue than that in adjacent tissue. After miR-133b transfection, its level was elevated till 48h, accompanied by lower proliferation in both SW-620 and HT-29 cells. According to that listed in http://www.targetscan.org, the 3'-UTR of TBPL1 mRNA (NM_004865) contains one putative binding site of miR-133b. This site was confirmed to be responsible for the negative regulation by miR-133b with luciferase assay. Further, Western blotting and immunohistochemistry both indicated a higher TBPL1 protein expression level in CRC tissue. Finally, a siRNA for TBPL1 transfection obviously slowed down the cell proliferation in both SW-620 and HT-29 cells. Conclusion: MiR-133b might act as a tumor suppressor and negatively regulate TBPL1 in CRC.

• Journal of Microbiology
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• v.44 no.3
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• pp.293-300
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• 2006

The Escherichia coli heat-labile enterotoxin B subunit (HLT-B) is one of the most powerful mucosal immunogens and known mucosal adjuvants. However, the induction of high levels of HLT-B expression in E. coli has proven a difficult proposition. Therefore, in this study, the HLT-B gene was cloned from pathogenic E. coli and expressed as a fusion protein with GST (glutathion S-transferase) in E. coli BL2l (DE3), in an attempt to harvest a large quantity of soluble HLT-B. The culture conditions, including the culture media used, temperature, pH and the presence of lactose as an inducer, were all optimized in order to obtain an increase in the expression of soluble GST-rHLT-B. The biological activity of the purified rHLT-B was assayed in a series of GMI-ELISA experiments. The findings of these trials indicated that the yield of soluble recombinant GST-rHLT-B could be increased by up to 3-fold, as compared with that seen prior to the optimization, and that lactose was a more efficient alternative inducer than IPTG. The production of rHLT-B, at 92 % purity, reached an optimal level of 96 mg/l in a 3.7 L fermentor. The specific GM1 binding ability of the purified rHLT-B was determined to be almost identical to that of standard CTB.

• Bulletin of the Korean Mathematical Society
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• v.36 no.4
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• pp.671-682
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• 1999

Using a base-point free version of the infinite symmetric product we define a fibrewise infinite symmetric product for any fibration $E\;\longrightarrow\;B$. The construction works for any commutative ring R with unit and is denoted by $R_f(E)\;l\ongrightarrow\;B$. For any pointed space B let $G_I(B)\;\longrightarrow\;B$ be the i-th Ganea fibration. Defining $M_R-cat(B):= inf{i\midR_f(G_i(B))\longrihghtarrow\;B$ admits a section} we obtain an approximation to the Lusternik-Schnirelmann category of B which satisfies .g.a product formula. In particular, if B is a 1-connected rational space of finite rational type, then $M_Q$-cat(B) coincides with the well-known (purely algebraically defined) M-category of B which in fact is equal to cat (B) by a result of K.Hess. All the constructions more generally apply to the Ganea category of maps.

• Journal of the Korean Mathematical Society
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• v.38 no.1
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• pp.101-123
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• 2001

For a linear operator Q from R(sup)d into R(sup)d and 0$\alpha$ and parameter b on the other. characterization of strictly (Q,b)-semi-stable distributions among (Q,b)-semi-stable distributions is made. Existence of (Q,b)-semi-stable distributions which are not translation of strictly (Q,b)-semi-stable distribution is discussed.

• Kyungpook Mathematical Journal
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• v.47 no.1
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• pp.127-132
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• 2007

In this paper, we show that if R is a commutative ring with identity and (S, ${\leq}$) is a strictly totally ordered monoid, then the ring [[$R^{S,{\leq}}$]] of generalized power series is a PF-ring if and only if for any two S-indexed subsets A and B of R such that $B{\subseteq}ann_R(|A)$, there exists $c{\in}ann_R(A)$ such that $bc=b$ for all $b{\in}B$, and that for a Noetherian ring R, $[[R^{S,{\leq}}$]] is a PP ring if and only if R is a PP ring.

• Journal of Astronomy and Space Sciences
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• v.25 no.2
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• pp.87-100
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• 2008

A total of 792 CCD images of V523 Cas were obtained on four nights of Jan. 2003 with the bvri CCD photometric system attached to a 61cm reflector of Sobaeksan Optical Astronomy Observatory (SOAO). The 17 standard stars in the images were used to establish transformation relations between our bvri system and the standard Johnson-Cousins BVRI system. We derived the tentative equations of transformation between two photometric systems as follows; V=v-0.0689(B-V)+0.0063, B-V=1.3197(b-v)-0.1733, V-R=0.9210(v-r)-0.1309, R-I=0.8892(r-i)-0.1055. Using these equations standard V magnitudes and their color indexes (B-V, V-R, R-I) for 57 stars in the field of the image were determined.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.536-544
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• 1997

This study presents test results of a residential window system air-conditioner using R22 and two potential alternative refrigerants, R407C and R410B. A series of performance tests was performed for the basic and liquid-suction heat exchange cycle in a psychrometric calorimeter test facility. For R407C, the same rotary compressor was used as in the R22 system. However, compressor for the R410B system was modified to provide the similar cooling capacity. The evaporator circuit was changed to get a counter-cross flow heat exchanger to take advantage of zeotropic mixture's temperature glide, and liquid-line suction-line heat exchange cycle was also considered to improve the performance of the system. Test results were compared to those for the basic R22 system.

• Korean Journal of Optics and Photonics
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• v.13 no.5
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• pp.414-420
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• 2002

We realized optical logic gates using a bacteriorhodopsin (bR) doped polymer film. The bR undergoes a complex photocycle characterized by several spectroscopically distinct intermediate states. We realized optical logic gates using a He-Ne laser (632.8 nm) and a He-Cd laser (413 nm) that consider B-state and absorption change of M-state in the photocycle of bR. Also, we realized high speed AND logic gate using He-Ne laser (632.8 nm) and the second harmonics at 532 nm from a pulsed Nd-YAG laser that considering absorption spectrum between B-state and K-state.

• Journal of the Korean Chemical Society
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• v.43 no.4
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• pp.447-455
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• 1999

Allyl (5R)-(Z)- and (5R)-(E)-6-[(2S)-2,3-isopropylidenedioxypropylidene]Penicillanate(10a and 10b) were prepared from allyl (5R)-dibromopenicillanate(6) via a sequence of reactions involving condensation with 2,3-O-isopropylidene-D-glyceraldehyde, reduction with $Zn-NH_4OAc$, and Mitsunobu elimination. Deprotection of isopropylidene and allyl groups of 10a gave potassium (5R)-(Z)-6-[(2S)-2,3-dihydroxypropylidene]penicillanate(4). However, deprotection of isopropylidene group of 10b afforded ${\alpha},\;{\beta}$-unsaturated-lactone(12). Allyl (5R)-(Z)- and (5R)-(E)-6-[(2S)-2-(t-butyldimethlsilyloxy)propylidene]penicillanate(18a and 18b) were prepared from ally (5R)-dibromopenicillanate(6) via a sequence of reactions involving condensation with (2S)-2-(t-butyldimethylsilyloxy)propanal(15), reduction with $Zn-NH_4OAc$ and Mitsunobu elimination or mesylation-elimination. Deprotection of t-butyldimethylsilyl and allyl groups of 18a and 18b gave potassium (5R)-(Z)- and (5R)-(E)-6-[(2S)-2-hydroxypropylidene]penicillanate(5a and 5b), respectively.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.244-252
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• 2007

Escherichia coli has a PhoR-PhoB two-component regulatory system to detect and respond to the changes of environmental phosphate concentration. For the E. coli W3110 strain growing under phosphate-limiting condition, the changes of global gene expression levels were investigated by using DNA microarray analysis. The expression levels of some genes that are involved in phosphate metabolism were increased as phosphate became limited, whereas those of the genes involved in ribosomal protein or amino acid metabolism were decreased, owing to the stationary phase response. The upregulated genes could be divided into temporarily and permanently inducible genes by phosphate starvation. At the peak point showing the highest expression levels of the phoB and phoR genes under phosphate-limiting condition, the phoB- and/or phoR-dependent regulatory mechanisms were investigated in detail by comparing the gene expression levels among the wild-type and phoB and/or phoR mutant strains. Overall, the phoB mutation was epistatic over the phoR mutation. It was found that PhoBR and PhoB were responsible for the upregulation of the phosphonate or glycerol phosphate metabolism and high-affinity phosphate transport system, respectively. These results show the complex regulation by the PhoR-PhoB two-component regulatory system in E. coli.