• Macromolecular Research
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• 제8권3호
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• pp.131-136
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• 2000

The synthesis of poly(2-ethynylpyridine) having glycidyl functionality was performed by the direct polymerization of 2-ethynylpyridine and epibromohydrin under mild reaction conditions without any initiator and catalysts. The polymerization proceeded well to give the resulting poly(2-ethynylpyridinium bromide) with a glycidyl functionality having relativity high molecular weight in high yields. The polymer structure was characterized by various instrumental methods to have the conjugated polymer backbone structure having glycidyl functionality. This ionic polymer was completely soluble in water, methanol, DMF, DMSO, and N,N-dimethylacetamide, but insoluble in THF, toluene, acetone, nitrobenzene, and n-hexane. This polymer system exhibited the UV-visible absorption around 300 and 520 nm and red photoluminescence spectrum around 725 nm.

• Applied Biological Chemistry
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• 제44권2호
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• pp.81-87
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• 2001

굴을 대상으로 조미 양념 젓갈(salt-fermented oyster)과 전통적인 게장의 제조법을 이용한 젓갈 제품(oyster in soy sauce)으로 새로운 형태의 젓갈을 제조하여 각각 진공 및 무진공 상태로 저장하면서 숙성 형태별 숙성 기간에 따른 이화학적 성분의 변화를 살펴 보았다. 굴 젓갈에 있어서 pH는 숙성 기간이 경과함에 따라 점차 감소했으나, 아미노태 질소(AN)와 휘발성 염기 질소(VBN)는 반대로 증가하는 경향을 나타냈으며, 함량에 있어서는 AN의 경우 진공 숙성시에, VBN은 무진공 숙성시에 더 많은 것으로 나타났다. 총균수는 어느 정도 증가했다가 감소하는 경향은 비슷하나 진공 숙성에 비해 무진공 숙성시에 더 현저하였다. 총 구성 아미노산에 있어서는 숙성이 진행됨에 따라 진공의 경우 함량이 증가했거나 감소한 경우라도 무진공 숙성시에 비해 함량이 높은 것으로 나타났다. 이상의 결과를 종합해 볼 때,무진공 숙성시보다 진공 숙성시 숙성이 지연되는 것으로 보여지며, 숙성 지연으로 인한 젓갈의 품질 유지 기간의 연장에도 진공 숙성이 효과적이라고 사료되었다.

• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.383-391
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• 2008

The glycans linked to the insect cell-derived glycoproteins are known to differ from those expressed in mammalian cells, partly because of the low level or lack of glycosyltransferase activities. GnT II, GnT IV, GnT V, and ST3Gal IV, which play important roles in the synthesis of tetraantennarytype complex glycan structures in mammalian cells, were overexpressed in Trichoplusia ni cells by using a baculovirus expression vector. The glycosyltransferases, expressed as a fusion form with the IgG-binding domain, were secreted into the culture media and purified using IgG sepharose resin. The enzyme assay, performed using a pyridylaminated-sugar chain as an acceptor, indicated that the purified glycosyltransferases retained their enzyme activities. Human erythropoietin expressed in T. ni cells (rhEPO) was subjected to in vitro glycosylation by using recombinant glycosyltransferases and was converted into complex-type glycan with terminal sialic acid. The presence of Nacetylglucosamine, galactose, and sialic acid on the rhEPO moiety was detected by a lectin blot analysis, and the addition of galactose and sialic acid to rhEPO was confirmed by autoradiography using $UDP-^{14}C-Gal\;and\;CMP-^{14}C-Sia$ as donors. The in vitro glycosylated rhEPO was injected into mice, and the number of reticulocytes among the ed blood cells was counted using FACS. A significant increase in the number of reticulocytes was not observed in the mice injected with in vitro glycosylated rhEPO as compared with those injected with rhEPO.

• International Journal of Oral Biology
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• 제42권3호
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• pp.91-97
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• 2017

Although anti-aging activities of melatonin, a hormone secreted by the pineal gland, have been reported in senescence-accelerated mouse models and several types of cells, its impact and mechanism on the senescence of human dental pulp cells (HDPCs) remains unknown. In this study, we examined the impact of melatonin on cellular premature senescence of HDPCs. Here, we found that melatonin markedly inhibited senescent characteristics of HDPCs after exposure to hydrogen peroxide ($H_2O_2$), including the increase in senescence-associated ${\beta}$-galactosidase (SA-${\beta}$-gal)-positive HDPCs and the upregulation of p21 protein, an indicator for senescence. In addition, as melatonin attenuated $H_2O_2$-stimulated phosphorylation of c-Jun N-terminal kinase (JNK), while selective inhibition of JNK activity with SP600125 significantly attenuated $H_2O_2$-induced increase in SA-beta-gal activity. Results reveal that melatonin antagonizes premature senescence of HDPCs via JNK pathway. Thus, melatonin may have therapeutic potential to prevent stress-induced premature senescence, possibly correlated with development of dental pulp diseases, and to maintain oral health across the life span.

• 한국의사학회지
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• 제24권2호
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• pp.77-86
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• 2011

This paper aims to find out the unique Oriental Medical characteristics of the prescription Gami-Bojeongsan(加味普正散), which can only be found in "Cheong-gang Euigam(晴崗醫鑑)" and the records of diagnosis by Kim Yeong Hoon. First, clues regarding Gami-Bojeongsan (加味普正散) in "Cheong-gang Euigam(晴崗醫鑑)" and the records of diagnosis by Kim Yeong Hoon have been collected, and then the origin of Gami-Bojeongsan(加味普正散) has been studied. Moreover, changes of prescriptions for common cold in East Asian Medicine have been looked into from historical perspective, and their connection to Gami-Bojeongsan(加味普正散) has also been researched. Lastly, connection of prescriptions for common cold found in royal records of the Chosun Dynasty to Gami-Bojeongsan(加味普正散) has been confirmed. The results are as follow: 1) Gami-Bojeongsan(加味普正散) is a most frequently used prescription in the records of diagnosis by Kim Yeong Hoon, and was used mostly in winter. It includes various modified versions. 2) Prescriptions that adopt Cyperi Rhizoma(香附子) as the sovereign medicinal, such as Gami-Bojeongsan(加味普正散), include Hyangsosan(香蘇散) of "Hejijufang(和劑局方)" and Hyang-gal-tang (香葛湯) of "Dexiaofang(得效方)". Hyang-gal-tang(香葛湯) is thought to have adopted Korean characteristics through "Dong-Eui-Bo-Gam (東醫寶鑑)" and "Je-Jung-Shin-Pyeon(濟衆新編)", and have continued its existence until it reached Gami-Bojeongsan(加味普正散). 3) These characteristics can be found in the royal records of the Chosun Dynasty, and also in Shin-Su-Tae-Eul-San(神授太乙散) of "Euibang-Yuchui (醫方類聚)".

• Journal of Radiation Protection and Research
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• 제36권3호
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• pp.119-126
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• 2011

Mitochondrial DNA (mtDNA) deletion is a well-known marker for oxidative stress and aging, and contributes to harmful effects in cultured cells and animal tissues. mtDNA biogenesis genes (NRF-1, TFAM) are essential for the maintenance of mtDNA, as well as the transcription and replication of mitochondrial genomes. Considering that oxidative stress is known to affect mitochondrial biogenesis, we hypothesized that ionizing radiation (IR)-induced reactive oxygen species (ROS) causes mtDNA deletion by modulating the mitochondrial biogenesis, thereby leading to cellular senescence. Therefore, we examined the effects of IR on ROS levels, cellular senescence, mitochondrial biogenesis, and mtDNA deletion in IMR-90 human lung fibroblast cells. Young IMR-90 cells at population doubling (PD) 39 were irradiated at 4 or 8 Gy. Old cells at PD55, and H2O2-treated young cells at PD 39, were compared as a positive control. The IR increased the intracellular ROS level, senescence-associated ${\beta}$-galactosidase (SA-${\beta}$-gal) activity, and mtDNA common deletion (4977 bp), and it decreased the mRNA expression of NRF-1 and TFAM in IMR-90 cells. Similar results were also observed in old cells (PD 55) and $H_2O_2$-treated young cells. To confirm that a increase in ROS level is essential for mtDNA deletion and changes of mitochondrial biogenesis in irradiated cells, the effects of N-acetylcysteine (NAC) were examined. In irradiated and $H_2O_2$-treated cells, 5 mM NAC significantly attenuated the increases of ROS, mtDNA deletion, and SA-${\beta}$-gal activity, and recovered from decreased expressions of NRF-1 and TFAM mRNA. These results suggest that ROS is a key cause of IR-induced mtDNA deletion, and the suppression of the mitochondrial biogenesis gene may mediate this process.

• KSBB Journal
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• 제10권3호
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• pp.343-348
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• 1995

LeI은 스테로이드를 통울에 투여하였을 때 분비가 촉진되어 항염증성 효과를 나타내는 calcium 의 존성 phospholipid 결합 단백질이다. S. cerevisiae는 대장균과 통물세포의 장점을 모두 가지고 있으므로 동물세포 유래의 이종 단백질의 분비 생산에 많이 이용되고 있다. 본 연구에서는 GAL10 promoter­p ppL-LCI유전자 LCI terminator로 구성된 pYGLPT5 로 LCI을 S. cerevisiae SEY2102에서 발현 분비시키고 각 분획으로 나누어 LCI양을 비교한 결과 protoplast 68.6 %. periplasmic 24 %, culture supernatant 7.4%로 분포하였다. pYGLPT5로 형질전환된 S. cereviswe 2102를 유가 배양한 결과, 최종적인 LCI의 생산량은 약 $500mg/\ell$ 였다. LCI은 N 말단 부근에 $CA^{++}$ 결합부위가 있으므로 이를 이용하여 hydroxylapatite column chromatography로 정 제하 였다. 배지로 분비된 34kDa LCI을 ultrafiltration 과 hydroxylapatite column chromatography 의 두 단계로 순도 99% 이상으로 정제할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제25권2호
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• pp.289-292
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• 2004

A trisaccharide, GlcNAcp- ${\beta}-(1{\to}3)-Galp-{\alpha}-(1{\to}2)$-6-deoxy-altroHepp- ${\alpha}-(1{\to}O$-propyl, as an O-antigenic repeating unit of C. jejuni serotype O:23 and O:36 was synthesized. Coupling of the GlcNPhth-(1${\to}$3)-Gal disaccharide donor with allyl 6-deoxy-altroHep acceptor in the presence of iodonium dicollidine perchlorate (IDCP) promoter afforded the ${\alpha}$-galactosidic trisaccharide with high stereoselectivities. Subsequent deacetalation, dephthaloylation, N-acetylation, and hydrogenolytic debenzylation furnished the title compound.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.367-370
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• 2002

A neutral polysaccharide, GP, was isolated from a fermentation broth of Ganoderma lucidum Acid hydrolysis and a paper chromatography analysis indicated that the polysacchride was composed of glucose, xylose, and mannose. The molecular weight was estimated to be $2.9{\times}10^4$. The oral administration of GP to mice showed that it can inhibit liver damage induced by GalN and $CCl_4$.

• Asian-Australasian Journal of Animal Sciences
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• 제6권4호
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• pp.581-589
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• 1993

A plasmid vector, $RSVLTR/{\beta}G2$, containing lacZ gene under the control of the RSVLTR promoter were transfected into chicken embryo fibroblasts by three different transfection methods. Calcium phosphate, lipsome and DEAE-dextran techniques were applied for transfection of chicken cells. A histochemical assay with X-gal was used as a simple method for screening transfected cells. Plasmid $RSVLTR/{\beta}G2$ was expressed proficiently in the chicken embryo fibroblast. Calcium phosphate-DNA precipitate transfection resulted in the highest efficiency for transient expression of $RSVLTR/{\beta}G2$. Transfected cells formed colonies on the 9th day of incubation indicating stable transformation of the inserted plasmid.