• 한국가축번식학회지
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• 제17권3호
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• pp.183-191
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• 1993

These experiments were carried out to investigate whether the enzyme is involved in zona hardening during normal activatin of the oocytes by sperm, and demonstrate peroxidase activity during in vitro fertilization of oocytes treated with peroxidase inhibitors(250 $\mu$M phenylhydrazine, 28mM sodium sulfite, 350mM glycine ethyl ester and 50mM sodium azide) and tyrosine analogue(12.5mM tyramine). Also, zona soluble properties of the ovarian oocytes incubated for 0, 5, 10 and 15 hr in the presence of pheylhydrazine or tyramine were studied by using $\alpha$-chymotrypsin. The results obtained from these experiments were summarized as follows ; 1. The rates of fertilizatin in control oocytes and oocytes treated with phenylhydrazine or tyramine were 69.8%, 62.3% and 88.2%, respectively. However in vitro fertilization in oocytes treated with three different peroxidase inhibitors, sodium sulfite, glycine ethyl ester and sodium azide, were not induced. The oocytes treated with phenylhydrazine had no significant effect on in vitro fertilization rate as compared to control. However there was a significantly different in fertilization between tyramine treated group and control group(P<0.01). 2. The zona solubility(t50) of control and fertilized oocytes in culture treated with phenylhydrazine or tyramine were 30.7, 26.0 and 16.3 min., respectively. Phenylhydrazine treated group and tyramine treated group had effect on inhibition of zona hardening as compared to control group. These results suggest that ovoperoxidase is involved in zona hardening during normal activation of the oocytes by sperm. 3. t50 of control oocytes and ovarian oocytes treated with phenylhydrazine or tyramine for 5, 10 and 15 hr in vitro were 14.0, 26.2 and 32.0 min., 14.5, 26.9 and 30.2 min., and 14.0, 24.3 and 31.2 min., respectively. These results suggest that zona hardening in ovarian oocytes matured for various times in vitro cannot be inhibited by peroxidase inhibitors and tyrosine analogue, that the spontaneous zona hardening incultured ovarian oocytes is not caused by the secretory products of cortical granules released during the cortical reaction, ovoperoxidase.

• 공업화학
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• 제9권7호
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• pp.1053-1058
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• 1998

Poly(vinyl alcohol)(PVA)와 n-butylaldehyde를 산촉매하에서 반응시켜 butyral unit의 함량이 서로 다른 poly(vinyl butyral)(PVB)를 합성하였으며, PVB내 butyral unit의 함량은 원소분석으로부터 결정하였다. 합성된 PVB와 p-azidobenzaldehyde를 산촉매하에서 반응시켜 azidobenzene기가 도입된 감광성수지(PVB-AZ)를 합성하였으며, PVB-AZ내 azidobenzene기의 함량은 UV 분광분석법으로 결정하였다. 합성된 PVB-AZ의 감광특성, 열적성질 및 용해특성을 조사하였으며, 상대감도 변화를 gray scale(GS)법으로 조사하였다.PVB-AZ내 butyral unit의 함량, azidobenzene기의 함량 및 현상용매에 따라 GS법에 의한 상대감도가 서로 다르게 나타났으며, 공유결합으로 감광기가 도입된 감광성수지(PVB-AZ)의 감도는 PVB에 감광제인 2,6-bis(p-azidobenzylidene) cyclohexanone(BAC)가 혼합된 감광성수지(PVB-BAC)보다 우수하였다.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3249-3253
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• 2014

A novel triazole-functionalized phenolic resin was developed, and its thermal and flame-retardant properties were investigated. The triazole group was incorporated as a pendant unit on the phenolic resin via copper-mediated click chemistry between propargylated phenolic resin and benzyl azide. The newly-developed triazole-functionalized phenolic resin showed higher thermal stability and char yield, together with a reduced total heat release (THR), than the non-functionalized bare phenolic resin, indicating enhanced flame retardancy for the triazole-functionalized phenolic resin.

• 한국식품위생안전성학회지
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• 제26권3호
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• pp.222-226
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• 2011

본 연구는 세포 내 기생세균인 S. typhimurium의 세포 내 대사과정에서 중요한 역할을 하는 respiratory nitrate reductase의 활성 및 활성 억제 물질인 sodium chlorate, sodium azide, 그리고 sodium cyanide으로 조성된 복합조성물을 이용하여 RAW 264.7 세포에 감염 된 S. typhimurium의 증식억제 효과와, S. typhimurium 감염 마우스에 대한 치료효과를 평 가하기 위하여 수행되었다. 복합조성물을 이용하여 RAW 264.7 세포 감염 S. typhimurium에 대한 증식억제 효과 확인시험을 수행한 결과, 세포 배양 24시간에 대조군과 비교하여 90% 이상의 S. typhimurium의 증식이 억제되었다. 또한, S. typhimurium을 감염시킨 마우스에 복합조성물을 투여한 결과, 70%의 높은 생존율을 보였다. 따라서 본 연구의 결과로부터, sodium chlorate, sodium azide, sodium cyanide로 조성된 복합조성물을 S. tyhimurium에 감염된 마우스에 투여할 경우 S. typhimurium의 증식을 억제하여 감염증상을 치료할 수 있을 것으로 기대된다.

• 폴리머
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• 제35권3호
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• pp.238-243
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• 2011

유기/무기 혼합 물질은 뛰어난 성능으로 인해 지난 수년간 다양한 분야에서 많은 관심을 받고 있다. 고분자 매트릭스에서의 무기 나노입자의 위치 및 분산을 조절하기 위해 싸이올(-SH) 기능기로 말단이 치환된 고분자 리간드가 나노입자의 표면 성질을 개질하는 데에 많이 사용되고 있다. 그러나 싸이올 기능기와 금속 나노입자간의 특정한 결합은 높은 온도에서는 매우 불안정하다. 본 연구진은 UV 경화가 가능한 azide 그룹을 고분자 리간드에 도입하여 열적으로 매우 안정한 금나노입자를 합성하여 보고한 바 있다. 본 연구에서는 더 나아가 표면 성질이 개질된 열적으로 안정한 금나노입자를 얻기 위해서 상대적으로 극성인 UV 경화 가능한 azide와 무극성인 스티렌의 공급 몰 비를 각각 다르게 해서 다양한 UV 경화성 고분자 리간드를 합성하였다. 이를 이용해 합성한 금나노입자는 열적으로 매우 안정하였으며 PS-b-PMMA와 같은 블록공중합체 매트릭스 내에서 금나노입자의 위치를 한 도메인에서 계면으로 정교하게 조절 할 수 있음을 확인하였다.

• Korean Journal of Chemical Engineering
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• 제35권11호
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• pp.2296-2302
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• 2018

Internally plasticized PVC was prepared via chemical reaction of azide PVC and alkynyl group containing castor oil methyl ester. The chemical structure of alkynyl group containing castor oil methyl ester and internally plasticized PVC was characterized with FT-IR and $^1H$ NMR. Properties of internally plasticized PVC, including thermal stability, tensile tests and resistance to extraction in different solvents, was investigated. The results showed that alkynyl group containing castor oil methyl ester, as internal plasticizer of PVC, not only decreased the $T_g$ of PVC from $84.6^{\circ}C$ to $41.6^{\circ}C$ efficiently, but also presented no plasticizer loss in five different solvents. The tensile tests showed that elongation at break and tensile strength of internally plasticized PVC was 353.8% and 18.1 MPa. The internally plasticized PVC has potential application in replacing the traditional PVC material in PVC products with high durability.

• 미생물학회지
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• 제29권4호
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• pp.238-242
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• 1991

Extracellular laccase secreted from Pleurotus ostreatus was activated by $Cu^{2+}$ and $Cu^{+}$ . The enzyme was strongly inactivated by 8-hydroxyquinoline, potassium cyanide, sodium azide, sodium bisulfite and 2-mercaptoethanol. The two ionogenic groups, which have pKa values of 5.60-5.70 and 6.70-6.85 respectively, were found to relate with the active site of this enzyme. The oxidation reactions were brought about by initial single electron transfer process on the active site. The enzyme was found to be a metalloprotein which had about 3.9 cupric ions per molecule of protein as a prosthetic group. The enzyme showed a strong peak at 605 nm and a weak shoulder at 330 nm in UV-Visible absorption spectrum. Both signals disappeated upon treatment of the enzyme with 4 electron equivalent ascorbate. These results indicate that type I Cu peak and type III Cu shoulder are present in laccase.

• Archives of Pharmacal Research
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• 제12권1호
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• pp.8-11
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• 1989

Reaction of 6-(acetoxymethyl) -2,4-dichloropyrido [3,2-d] pyrimidine (I) with some nucleophiles was investigated. When I reacted with sodium azide afforded 2,4-diazido derivative (II). Treatment of II with sodium hydroxide underwent cyclization of the 2-azido group to tetrazolo, replacement of 4-azido group by hydroxide ion, and hydrolysis of 6-ace-foxy moiety to hydroxy methyl derivative (III). While, reaction of I with hydrazine hydrate resulted in the formation of 2,4 dihydrozino-6-hydroxymethyl derivative (lV).

• 대한방사성의약품학회지
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• 제6권2호
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• pp.177-181
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• 2020

Dual-modality imaging strategy using near-infrared fluorescence (FLI) and photoacoustic imaging (PAI) demands a suitable probe to enable dual-modular signal production. Herein, we demonstrate a synthetic protocol of small molecular dye for dual-modular FLI and PAI. A condensation reaction between squaric acid and carboxypentyl benzoindolium, and followed by basic hydrolysis to give the benzoindole derived squaraine (BSQ) dye in 49% yield. Next, the carboxylic acid group of BSQ was further functionalized with N-hydroxysuccinimide or azide group for an efficient conjugation with a targeting biomolecule. BSQ showed a maximum fluorescent emission at around 680 nm and the photoacoustic signal reached a maximum intensity at 680-700 nm. Based on these results, we conclude that BSQ analogs will be useful probes for dual-modular (FLI/PAI) imaging studies in animal models.

• Restorative Dentistry and Endodontics
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• 제27권1호
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• pp.12-15
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• 2002

The first purpose of present study was to compare the anticariogenic effect of compomer, resin modified glass ionomer cement and composite (RMGIC). The second purpose was to evaluate the recently introduced methods, which use confocal scanning micro-scope, in detecting initial caries around restoration. 2$\times$4$\times$1.5mm cavities were prepared from the recently extracted 50 human teeth on the buccal or lingual surface. The prepared teeth were randomly devided into 5 groups and restored with each filling material. Group 1: Dyract AP, Group 2: compoglass F, Group 3: F2000, Group 4: Z100. Group 5:Fuji II LC. The teeth were stored for 30 days in the distilled water, then stored in the buffer solution for artificial caries development: pH 4.3, lactic acid 100 mM, calcium 16 mM, phosphate 8mM, sodium azide 3mM. Then, the samples were sectioned longitudinally and examined with confical scanning microscope. The results showed that the use of compomer and resin modified glass ionomer cement showed caries inhibition zone whereas the composite did not. There was no difference in the width of caries inhibition zone between compomers and RMGIC. The confocal scanning microscope was useful in detecting initial caries around restoration.