• Food Science and Biotechnology
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• v.18 no.2
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• pp.312-316
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• 2009

Antioxidant-rich oils were extracted from different parts of sea buckthorn berry with supercritical $CO_2$ (SC-$CO_2$) and n-hexane. The functional components were analyzed and the extracts were screened for their potential as radical scavengers in 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2'-azinobis-3-ethylbenzotiazoline-6-sulphonic acid (ABTS), galvinoxyl systems. Minor differences were found in fatty acid composition of oils extracted by the two methods. Seed oil contains the highest content of tocopherols while pulp oil and whole berry oil possessed higher concentration of carotenoids. Whole berry oil, pulp oil, and seed oil extracted by SC-$CO_2$ showed 91.7, 90.9, and 93.5% radical scavenging activity (RSA) at 6 mg/mL towards DPPH and 74.3, 54.3, and 74.8% towards galvanoxyl radical at 10 mg/mL. The hexane-extracted oils showed similar scavenging ability. However, the oils obtained by hexane showed significantly higher RSA (p<0.05) than those obtained by SC-$CO_2$ while whole berry oil has the highest RSA towards ABTS among 3 oil samples.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.94-98
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• 2005

Bone resorption surrounding tooth root causes tooth loss in periodontitis patients. Osteoclast has bone resorption activity. Effects of Artemisia asiatica on bone resorption induced by periodontopathogens, Porphyromonas gingivalis and Treponema denticola, were examined using co-culture systems of mouse osteoblasts and bone marrow cells. Addition of A. asiatica ethanol extract to bacterial sonicate abolished bacteria-induced osteoclastogenesis. To determine inhibitory mechanism of A. asiatica against osteoclastogenesis, effects of A. asiatica on expressions of osteoclastogenesis-inducing factors such as receptor activator of NF-${\kappa}B$ ligand (RANKL), prostaglandin $E_2\;(PGE_2)$, interleukin (IL)-1, and tumor necrosis factor (TNF)-${\alpha}$, in osteoblasts were examined. A. asiatica suppressed expressions of RANKL, $PGE_2$, IL-$1{\beta}$, and TNF-${\alpha}$ increased by each bacterial sonicate. These results suggest inhibitory action of A. asiatica against osteoclastogenesis is associated with down-regulations of RANKL, $PGE_2$ IL-$1{\beta}$, and TNF-${\alpha}$ expressions.

• Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.8-15
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• 2007

Rhodopsin, a dim-light receptor, is a model system for the study of G protein-coupled receptors that transduce extracellular signals into cells. To study the molecular mechanisms of visual systems in fish, the rod opsin gene of olive flounder Paralichthys olivaceus was characterized. The full-length P. olivaceus opsin gene was obtained by PCR amplification of genomic DNA, as well as cDNA synthesis. A comparison of clones obtained from both methods indicated that the olive flounder rod opsin gene lacks introns. Sequence analysis of the opsin gene indicated that it contains a 1,056-bp open reading frame encoding 352 amino acids. The deduced amino acid sequence contains features of typical rod opsins, such as sites for Schiff's base formation (K296) and its counterion (E113), disulfide formation (C110 and C187), and palmitoylation (C322 and C323). An opsin sequence alignment showed the highest similarity between P. olivaceus and Solea solea (95.1%), followed by Hippoglossus hippoglossus (94.5%). An opsin phylogenetic tree revealed a close relationship between olive flounder and teleost rod opsins.

• KSBB Journal
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• v.17 no.4
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• pp.321-325
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• 2002

Chiral epoxides are valuable intermediates for the asymmetric synthesis of enantiopure bioactive compounds. Microbial epoxide hydrolases (EHs) are newly discovered enzymes and versatile biocatalysts for the preparation of chiral epoxides by enantioselective hydrolysis of cheap and easily available racemic epoxide substrates. EHs are commercially potential biocatalysts due to their characteristics such as high enantioselectivity, cofactor-independent catalysis, and easy-to-Prepare catalysts. In this Paper, recent progresses in biochemistry and molecular biology of EH and developments of novel reaction systems are reviewed to evaluate the commercial feasibility of EH-catalyzed hydrolytic kinetic resolution for the production of chiral epoxides.

• Animal cells and systems
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• v.16 no.1
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• pp.69-76
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• 2012

This study was conducted to examine how a low-head dam removal (partial removal) could affect benthic macroinvertebrate communities in a stream. Benthic macroinvertebrates and substrates were seasonally sampled before and after dam removal (March 2006-April 2007). Benthic macroinvertebrates and substrates were quantitatively sampled from immediately upstream (upper: pool) and downstream (lower: riffle) sites, the location of the dam itself (middle), and immediately above the impoundment (control: riffle). After the removal, species richness and density of benthic macroinvertebrates as well as the EPT group (Ephemeroptera, Plecoptera and Trichoptera) increased to higher levels than those before the removal, while functional feeding groups and habitat orientation groups changed more heterogeneously at the upper site. At the lower site, species richness and density decreased somewhat immediately after dam removal, which was associated with an increase of silt and sand, but recovered after monsoon floods which helped to enhance substrate diversity at the upper site. Decreased dominance index and increased diversity index in both the upper and lower sites are evidence of positive effects from the dam removal. In conclusion, we suggest that even a partial removal of a dam, resulting in increased substrate diversity in the upper site, could sufficiently help rehabilitate lost ecological integrity of streams without major habitat changes.

• Animal cells and systems
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• v.6 no.2
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• pp.167-170
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• 2002

The long terminal repeats (LTRs) of human endogenous retrovirus (HERV) have been found to be coexpressed with sequences of closely located genes. It has been suggested that the LTR elements have contributed to the structural change or genetic variation of human genome connected to various diseases and evolution. We examined the HERV-W LTR elements in various cancer cells (2F7, A43l , A549, HepG2, MIA-PaCa-2, PC-3, RT4, SiHa, U-937, and UO-31). Using genomic DNA from the cancer cells, we performed PCR amplification and identified twelve new HERV-W LTR elements. Those LTR elements showed a high degree of sequence similarity (88-99％) with HERV-W LTR (AF072500). A phylogenetic tree obtained by the neighbor-joining method revealed that HERV-W LTR elements could be mainly divided into two groups through evolutionary divergence. Three HERV-W LTR elements (RT4-2, A43l-1, and UO3l-2) belonged to Group 1, whereas nine LTR elements (2F7-2, A549-1, A549-3, HepG2-3, MP2-2, PC3-1, SiHa-8, SiHa-10, and U937-1) belonged to Group 11. Taken together, our new sequence data of the HERV-W LTR elements may contribute to an understanding of tissue-specific cancer by genomic instability of LTR integration.

• Animal cells and systems
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• v.10 no.4
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• pp.197-201
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• 2006

Diaminopimelate decarboxylase (DAPDC, EC 4.1.1.20) catalyzes the conversion of diaminopimelate into lysine (Lys), which is the last step in Lys biosynthetic pathway. The genes for DAPDC have been reported in many bacteria, and more recently in Arabidopsis. Here we report characterization of a gene for DAPDC from rice (OsDAPDC). Sequence analysis of a cDNA clone revealed a full-length open reading frame for OsDAPDC that encoded 490 amino acids, approximately 53.2 kDa protein. The OsDAPDC protein contains a consensus binding site for pyridoxal-5'-phosphate as a cofactor and has a sequence at the amino terminus that resembles a transit peptide for localization to plastids, similar to that of Arabidopsis. Single gene encoding DAPDC was found in chromosome II in rice. The predicted amino acid sequence of OsDAPDC is highly homologous to that of the enzymes for DAPDC encoded by lysA of many bacteria. Expression of OsDAPDC in lysA mutants of Escherichia coli shows that the gene is able to functionally complement the mutants. These results suggest that OsDAPDC encodes a protein for diaminopimelate decarboxylase in rice.

• Animal cells and systems
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• v.7 no.3
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• pp.265-269
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• 2003

Vascular endothelial growth factor (VEGF) is a potent regulator of normal and abnormal angiogenesis. Recent literature suggests that VEGF has several activities that may amplify acute inflammation reactions. Dysregulated VEGF expression has been implicated as a major contributor to the development of a number of common disease pathologies. One of common mutations in the 3'- untranslated region of the VEGF gene, a C\longrightarrowT exchange at nucleotide position 936, has been found to be significantly associated with VEGF expression levels in the plasma from a previous Austrian study. The frequency of this mutation could be important genetic information regarding tumor growth and angiogenesis related diseases. The aim of this study was to investigate the frequency distribution of this mutation in general Korean population. We examined the statistical data from 207 healthy Korean subjects. Observed numbers (%) of 936T were 28.5 (CT) and 3.9 (TT), respectively. The mutant allele frequency of 936T in Korean subjects was 0.18, which appeared somewhat higher than that in Austrian subjects.

• Animal cells and systems
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• v.7 no.3
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• pp.173-186
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• 2003

The transition metal cadmium is a serious occupational and environmental toxin. To inhibit cadmium-induced damage, cells respond by increasing the expression of genes that encode stress-responsive proteins. The metal-regulatory transcription factor 1 (MTF-1) is a key regulator of heavy-metal induced transcription of metallothionein-I and II and other genes in mammals and other metazoans. Transcriptional activation of genes by MTF-1 is mediated through binding to metal-responsive elements in the target gene promoters. Phosphorylation of MTF-1 plays a critical role in the cadmium-inducible transcriptional activation of metallothionein and other responses. Studies using inhibitors indicate that multiple kinases and signal transduction cascades, including those mediated by protein kinase C, tyrosine kinase and casein kinase II, are essential for cadmium-mediated transcriptional activation. In addition, calcium signaling is also involved in regulating metal-activated transcription. In several species, cadmium induces heat shock genes. Recently much progress has been made in elucidating the cellular machinery that regulates this metal-inducible gene expression. This review summarizes these recent advances in understanding the role of some known cadmium-responsive genes and the molecular mechanisms that activate metal-responsive transcription factor, MTF-1.

• Animal cells and systems
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• v.12 no.4
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• pp.279-286
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• 2008

Development and distribution of larval Dungeness crab, Cancer magister Dana, 1852 were investigated in southeastern Alaska from late May to mid-September in 2004. Larvae were collected during daylight hours at three inner and two outer Glacier Bay stations at the two different depths in the water column, above and below the thermocline. Larval density decreased dramatically for three larval stages, zoeae I(ZI), zoeae IV, and zoeae V(ZV), but relatively little for zoeae II and zoeae III. ZI predominated at all stations in late May and were collected until late July. Larval stages progressed seasonally from ZI to ZV and density decreased from ZI through ZV. The densities of each zoeal stage at the inner and outer bay stations and at the shallow and deep depths were similar. The density of each larval stage above(shallow) and below(deep) the thermocline and between inner and outer bay stations were not significantly different. The occurrence of larval Dungeness crab is dramatically later than in other parts of the species range, in that larvae appear in abundance beginning in late May. The pattern of spatial distribution of larval stages for the inland waters of Alaska was also markedly different than the patterns reported for Dungeness crab larvae from other parts of the species range, in that the early and intermediate stages occurred within inland waters; from British Columbia to California these larval stages increase in abundance with distance offshore.