• Archives of Pharmacal Research
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• v.24 no.5
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• pp.455-465
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• 2001

The highly potent cytotoxic DNA-DNA cross-linker consists of two cyclopropa[c]pyrrolo[3,4-3]indol-4(5H)-ones insoles [(+)-CPI-I] joined by a bisamido pyrrole (abbreviated to "Pyrrole"). The Pyrrole is a synthetic analog of Bizelesin, which is currently in phase II clinical trials due to its excellent in vivo antitumor activity. The Pyrrole has 10 times more potent cytotoxicity than Bizelesin and mostly form DNA-DNA interstrand cross-links through the N3 of adenines spaced 7 bp apart. The Pyrrole requires a centrally positioned GC base pair for high cross-linking reactivity (i.e., $5^1$-T$AT_2$A*-$3^1$), while Bizelesin prefers purely AT-rich sequences (i.e., $5^1$-T$AT_4$A*-$3^1$, where /(equation omitted) represents the cross-strand adenine alkylation and A* represents an adenine alkylation) (Park et al., 1996). In this study, the high-field $^1$H-NMR and rMD studies are conducted on the 1 1-mer DNA duplex adduct of the Pyrrole where the 5′(equation omitted)TAGTTA*-3′sequence is cross-linked by the drug. A severe structural perturbation is observed in the intervening sequences of cross-linking site, while a normal B-DNA structure is maintained in the region next to the drug-modified adenines. Based upon these observations, we propose that the interplay between the bisamido pyrrole unit of the drug and central C/C base pair (hydrogen-bonding interactions) is involved in the process of cross-linking reaction, and sequence specificity is the outcome of those interactions. This study suggests a mechanism for the sequence specific cross-linking reaction of the Pyrrole, and provides a further insight to develop new DNA sequence selective and distortive cross-linking agents.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7911-7916
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• 2015

Serum anti-Helicobacter pylori antibodies and pepsinogens (PGs) have been used as gastric cancer screening and gastric mucosal status markers. Nepal is a low risk country for gastric cancer. However, the mountainous populace in the northern region culturally linked to Tibet as well as Bhutan, a neighboring country, have a high risk of GC. We collected gastric biopsy specimens and sera from 146 dyspeptic patients living in Kathmandu, Nepal. We also examined the sera of 80 volunteers living in the mountainous regions of the Himalayas. The optimal cut-off was calculated for serum biomarkers against the histology. Kathmandu patients (43.8%) were serologically positive for H. pylori infection, which was significantly lower than that for the mountainous (61.3%, P = 0.01). The same results also found in the prevalence of PG-positivity, PG I levels and PG I/II ratios (P = 0.001, P<0.0001 and P = 0.03, respectively). Moreover, the PG I/II ratios were significantly, and inversely correlated with the OLGA score (r = -0.33, P<0.009). The low incidence of gastric cancer in Nepal can be attributed to low gastric mucosal atrophy. However, the mountainous subjects have high-risk gastric mucosal status, which could be considered a high-risk population in Nepal.

• Animal cells and systems
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• v.13 no.4
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• pp.447-452
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• 2009

We cloned the complete complementary DNA (cDNA) of a Pacific oyster (Crassostrea gigas) cytochrome P450 (CYP450)-related protein using rapid amplification of cDNA ends (RACE). The cDNA included a 1470 bp open reading frame that began with the first ATG codon at position 103 bp and ended with a TAG stop codon at position 1573 bp (GenBank accession EF451959). The sequence had all major functional domains and characteristics of previously characterized CYP450 molecules, including the heme-binding region (FGVGRRRCVG) and putative arginine codon (R) integral to enzymatic function. An NCBI/GenBank database comparison to other CYP450 genes revealed that the deduced C. gigas CYP450 amino acid sequence is similar to that of mouse (Mus musculus) CYP450 2D/II (28%, accession AK078880), rabbit (Oryctolagus cuniculus) CYP450 2D/II (28%, AB008785), and white-tufted-ear marmoset (Callithrix jacchus) CYP450 2D (28%, AY082602). Thus, although the C. gigas CYP450 we cloned appears to belong to the 2D type of the CYP450 group, it has low similarity to this type. CYP450 mRNA expression increased over 6 h in C. gigas gills at $30^{\circ}C$ and $10^{\circ}C$, and then decreased, indicating that CYP450 plays an important role in C. gigas exposed to water temperature changes. This finding can be used as a physiological index for Pacific oysters exposed to changing water temperatures.

• Bulletin of the Korean Chemical Society
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• v.9 no.6
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• pp.368-376
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• 1988

Transition metal PSSA ionomers containing Co(II), Ni(II), Cr(III), Ru(III), and Rh(III) are investigated by IR, Far-IR, UV-Vis and DSC. Reliable IR Spectroscopic criteria are established for assessing the degree of ion-exchange of PSSA ionomers and the local structures around metal cations in them. In the hydrated transition metal PSSA ionomers, the ionic groups are solvated by water molecules and there is no significant interactions between sulfonate group and metal cations. The visible spectra indicated that metal cations are present as [M$(H_2O)_6$]$^{n+}$ with Oh symmetry. Their $T_g$ values increase as the extent of ionic site concentration increases, but there is no direct dependence of $T_g$ on the nature of metal cations or their oxidation states. Thus, the water content in PSSA ionomer is found to have dominant influence on $T_g$ of hydrated transition metal PSSA ionomers. Dehydration of the hydrated transition metal PSSA ionomers results in direct interaction between ionic groups and significant color changes of the ionomers due to the changes of the local structures around metal cations. On the base of spectral data, their local structures are discussed. In case of dehydrated 12.8 and 15.8 mol % transition metal PSSA ionomers, no glass transition is observed in 25-$250^{\circ}C$ region and this is believed to arise from the formation of highly crosslinked structures caused by direct coordination of sulfonate groups of metal cations. In the 6.9 mol % transition metal PSSA ionomers, the glass transition is always observed whether they are hydrated or dehydrated and this is though to be caused by the sufficient segmental mobility of the polymer backbone.

• Parasites, Hosts and Diseases
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• v.59 no.1
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• pp.103-108
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• 2021

To date, there is no report on the genetic diversity of ticks in these regions. A total of 370 representative ticks from the south and east regions of Kazakhstan (SERK) and Xinjiang Uygur Autonomous Region (XUAR) were selected for molecular comparison. A fragment of the mitochondrial cytochrome c oxidase subunit I (cox1) gene, ranging from 631 bp to 889 bp, was used to analyze genetic diversity among these ticks. Phylogenetic analyses indicated 7 tick species including Hyalomma asiaticum, Hyalomma detritum, Hyalomma anatolicum, Dermacentor marginatus, Rhipicephalus sanguineus, Rhipicephalus turanicus and Haemaphysalis erinacei from the SERK clustered together with conspecific ticks from the XUAR. The network diagram of haplotypes showed that i) Hy. asiaticum from Almaty and Kyzylorda Oblasts together with that from Yuli County of XUAR constituted haplogroup H-2, and the lineage from Chimkent City of South Kazakhstan was newly evolved; and ii) the R. turanicus ticks sampled in Israel, Almaty, South Kazakhstan, Usu City, Ulugqat and Baicheng Counties of XUAR were derivated from an old lineage in Alataw City of XUAR. These findings indicate that: i) Hy. asiaticum, R. turanicus and Ha. erinacei shared genetic similarities between the SERK and XUAR; and ii) Hy. marginatum and D. reticulatus show differences in their evolution.

• Journal of the Korean earth science society
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• v.43 no.3
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• pp.351-366
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• 2022

We investigated the kinematic activity of the Type II Seyfert galaxy Mrk 1 based on H𝛽 and [O III] 5007 extracted from the MR 1 grism spectra observed with the OASIS attached to the CFHT 3.6 m telescope. The [O III] forbidden Gaussian line profiles exhibited asymmetric features with an excess of the blue component: (1) strongest at a distance of about 960 pc from the galaxy center, and (2) a wider line width of about ~900 km s^-1 in the NS direction of the center. The velocity distributions in the spectral images showed blue or approaching flow motion in the NE zone, while receding in the SW zone, implying the counter-clockwise rotation. The radial velocity data showed that the center of the AGN region appears to be blocked by gas-dust approaching toward the Earth.

• Advances in environmental research
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• v.11 no.1
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• pp.31-38
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• 2022

The current observational epidemiological study analyzed blood lead levels (BLLs) in occupationally exposed workers from Riyadh region, Saudi Arabia and correlated them with the alterations in the differential cell populations of the WBC panel (lymphocytes [Lym %], mixed [Mid %] cells, and neutrophils [Neu %]). In addition, we examined the effect of confounding factors and their relation to BLLs. BLLs were estimated using the LeadCare II analyzer and hematological parameters using the ADVIA 120 analyser. An inferential analysis was conducted to detect association between the observations and the subjects' clinical characateristics. A total of 132 male subjects were included in the final analyses. Based on CDC guidelines, the subjects were categorized as Group I (BLL <10 ㎍/dL; n=118) or Group II (BLL >10 ㎍/dL; n=14) with average BLLs of 4.4 ㎍/dL and 18.1 ㎍/dL, respectively (p <0.0001). The percentages of Mid cells (p <0.0001) and neutrophils (p=0.048), were significantly altered in subjects with High BLL. A regression analysis indicated that subjects > 50 years of age had significantly higher BLLs (53.2 ㎍/dL) than younger age sub-groups (p <0.0001). Age, education, and profession were significant predictors for lead toxicity. Pb exposure is a major public health issue in Saudi Arabia and calls for further investigations on the cellular and molecular effects on hematological system.

• Journal of the Korean earth science society
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• v.28 no.7
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• pp.847-856
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• 2007

The Planetary nebula NGC 6881 displays quadrupole morphology and it also has a jet feature in its image. We investigated the line profiles of the optical region spectral emission lines, using the Hamilton Echelle Spectrograph (HES) at the Lick observatory. The HES data obtained in this study was the radiation coming from the inner region within the diameter of 4 second of arc. Expansion velocity was obtained, based on the strong emission line profiles of e.g. H, Hel, Hell, [OIII], [NII], [ArIII], [SII], and [SIII}, using the IRAF and StarLink/Dipso reduction packages. The HI recombination lines showed one single peak profile, while the He and forbidden strong lines displayed double peaks. The results of this study show that the outflow velocity of gas increases radially outwards due to the central stellar radiation pressure. It was concluded that three central rings appeared in the HST image are the result of a combined structure of bipolar cones (seen in e.g. HI lines) and a ring (seen in He, [SIII] lines) in projection.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.987-996
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• 2018

Bacterial programmed cell death is regulated by the toxin-antitoxin (TA) system. YhaV (toxin) and Pr1F (antitoxin) have been recently identified as a type II TA system in Escherichia coli. YhaV homologs have conserved active residues within the C-terminus, and to characterize the function of this region, we purified native YhaV protein (without denaturing) and constructed YhaV proteins of varying lengths. Here, we report a new low-temperature method of purifying native YhaV, which is notable given the existing challenges of purifying this highly toxic protein. The secondary structures and thermostability of the purified native protein were characterized and no significant structural destruction was observed, suggesting that the observed inhibition of cell growth in vivo was not the result of structural protein damage. However, it has been reported that excessive levels of protein expression may result in protein misfolding and changes in cell growth and mRNA stability. To exclude this possibility, we used an [$^{35}S$]-methionine prokaryotic cell-free protein synthesis system in vitro in the presence of purified YhaV, and two C-terminal truncated forms of this protein (YhaV-L and YhaV-S). Our results suggest that the YhaV C-terminal region is essential for mRNA interferase activity, and the W143 or H154 residues may play an analogous role to Y87 of RelE.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.87-87
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• 2010

Photoelectrochemical (PEC) systems are promising methods of producing H2 gas using solar energy in an aqueous solution. The photoelectrochemical properties of numerous metal oxides have been studied. Among them, the PEC systems based on TiO2 have been extensively studied. However, the drawback of a PEC system with TiO2 is that only ultraviolet (UV) light can be absorbed because of its large band gap (3.2 - 3.4 eV). Two approaches have been introduced in order to use PEC cells in the visible light region. The first method includes doping impurities, such as nitrogen, into TiO2, and this technique has been extensively studied in an attempt to narrow the band gap. In comparison, research on the second method, which includes visible light water splitting in molecular photosystems, has been slow. Mallouk et al. recently developed electrochemical water-splitting cells using the Ru(II) complex as the visible light photosensitizer. the dye-sensitized PEC cell consisted of a dye-sensitized TiO2 layer, a Pt counter electrode, and an aqueous solution between them. Under a visible light (< 3 eV) illumination, only the dye molecule absorbed the light and became excited because TiO2 had the wide band gap. The light absorption of the dye was followed by the transfer of an electron from the excited state (S*) of the dye to the conduction band (CB) of TiO2 and its subsequent transfer to the transparent conducting oxide (TCO). The electrons moved through the wire to the Pt, where the water reduction (or H2 evolution) occurred. The oxidized dye molecules caused the water oxidation because their HOMO level was below the H2O/O2 level. Organic dyes have been developed as metal-free alternatives to the Ru(II) complexes because of their tunable optical and electronic properties and low-cost manufacturing. Recently, organic dye molecules containing multi-branched, multi-anchoring groups have received a great deal of interest. In this work, tri-branched tri-anchoring organic dyes (Dye 2) were designed and applied to visible light water-splitting cells based on dye-sensitized TiO2 electrodes. Dye 2 had a molecular structure containing one donor (D) and three acceptor (A) groups, and each ended with an anchoring functionality. In comparison, mono-anchoring dyes (Dye 1) were also synthesized. The PEC response of the Dye 2-sensitized TiO2 film was much better than the Dye 1-sensitized or unsensitized TiO2 films.