• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.25-40
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• 1991

Four root canal sealers, Apatite Root Sealer I and II composed mainly of hydroxyapatite/tricalciumphosphate, Sealapex containing calcium hydroxide, and Roth Sealer composed of zinc oxide - eugenol were compared on the culture of L929 fibroblasts. MIT (Methyl Thiazole Tetrazolium Bromide) colorimetric technique was used to measure the mitochondrial dehydrogenase activity. Results were as follows: 1. Hydroxyapatite/tricalcium phosphate mixed sealers were significantly less toxic compared with calcium hydroxide and zinc oxide - eugenol type sealers. High pH of the calcium hydroxide sealer and release of eugenol component from the zinc oxide - eugenol type sealer were presumed to be the cause of the toxicity of these two sealers. In no cases, there were more cytoblastic effects in hydroxyapatite/tricalcium phosphate mixed sealers compared to the control groups. 2. In all experimental groups, toxicity was decreased as dilutions were increased. However in zinc oxide-eugenol type sealer the cell activity was weakened for all dilution groups. 3. Regarding the effect of setting time, Apatite I and Sealapex were less toxic as the setting progressed. Apatite II kept constant regardless of the different time ellapsed after setting but Roth sealer revealed significantly higher toxicity for all experimental groups. 4. Comparing two different culture periods of 24 hours and 72 hours, Apatite I showed higher cell activities in longer period(72 hours) while Apatite II did not. Sealapex and Roth sealer, however, showed significantly lower cell activities in longer period.

• 약학회지
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• 제52권6호
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• pp.488-493
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• 2008

2-Aminothiazole ring as a bioisoster of catechol in dopamine has provided with good oral availability and lipophilic property. 2-Aminoindan, is a rigid form of dopamine, was evaluated as a dopamine D3 agonist with low neurotoxicity. Dopamine D3 agonist was evaluated as selective for the treatment of Parkinson's disease. In order to develop a novel dopamine D3 agonist, we tried to synthesize the aminothiazoloindenoxazine derivative that is a hybrid structure of aminoindenoxazine and thiazole ring. cis-2-Amino-1-indanol (2) was synthesized from 1,2-indandione-2-oxime by catalytic hydrogenation and it was treated with chloroacetyl chloride and NaH in benzene solution to give (${\pm}$)-cis-4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one (6). Nitration of 6 by the mixed acid gave 8-nitro compound (7) and the carbonyl group of 7 was reduced with $LiAlH_4$ to afford compound (8). 8 was reduced to form (${\pm}$)-cis-8-amino-2,3,4,4a,5,9b-hexahydroindeno[1,2-b][1,4]oxazine (9) and finally it was cyclized with KSCN in glacial acetic acid to yield (${\pm}$)-cis-8-amino-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno[1,2-b][1,4]oxazine (10).

• 통합자연과학논문집
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• 제9권3호
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• pp.190-198
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• 2016

Xanthine Oxidase is an enzyme, which oxidizes hypoxanthine to xanthine, and xanthine to uric acid. It is widely distributed throughout various organsincluding the liver, gut, lung, kidney, heart, brain and plasma. It is involved in gout pathogenesis. In this study, we have performed Comparative Molecular Field Analysis (CoMSIA) on a series of 2-(indol-5-yl) thiazole derivatives as xanthine oxidase (XO) inhibitors to identify the structural variations with their inhibitory activities. Ligand based CoMSIA models were generated based on atom-by-atom matching alignment. In atom-by-atom matching, the bioactive conformation of highly active molecule 11 was generated using systematic search. Compounds were aligned using the bioactive conformation and it is used for model generation. Different CoMSIA models were generated using different alignments and the best model yielded across-validated $q^2$ of 0.698 with five components and non-cross-validated correlation coefficient ($r^2$) of 0.992 with Fisher value as 236.431, and an estimated standard error of 0.068. The predictive ability of the best CoMSIA models was found to be $r{^2}_{pred}$ 0.653. The study revealed the important structural features required for the biological activity of the inhibitors and could provide useful for the designing of novel and potent drugs for the inhibition of Xanthine oxidase.

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3909-3919
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• 2013

The aim of the present investigation was to evaluate the effect of A ferruginea extract on Dalton's lymphoma ascites (DLA) induced tumours in BALB/c mice. Experimental animals received A ferruginea extract (10 mg/kg.b.wt) intraperitoneally for 14 consecutive days after DLA tumor challenge. Treatment with extract significantly increased the life span, total white blood cell (WBC) count and haemoglobin (Hb) content and decreased the level of serum aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (${\gamma}$-GT) and nitric oxide (NO) in DLA bearing ascites tumor models. In addition, administration of extract significantly decreased the tumour volume and body weight in a DLA bearing solid tumor model. The levels of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-${\alpha}$), interleukin-1 beta (IL-$1{\beta}$), interleukin-6 (IL-6) and granulocyte monocyte-colony stimulating factor (GM-CSF), as well as pro-angiogenic growth factors such as vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS) were elevated in solid tumour controls, but significantly reduced by A ferruginea administration. On the other hand, the extract stimulated the production of interleukin-2 (IL-2) and interferon-gamma (IFN-${\gamma}$) in animals with DLA induced solid tumours. Increase in $CD4^+$ T-cell population suggested strong immunostimulant activity for this extract. GC/MS and LC/MS analysis showed quinone, quinoline, imidazolidine, pyrrolidine, cyclopentenone, thiazole, pyrazole, catechin and coumarin derivatives as major compounds present in the A ferruginea methanolic extract. Thus, the outcome of the present study suggests that A ferruginea extract has immunomodulatory and tumor inhibitory activities and has the potential to be developed as a natural anticancer agent.

• Journal of Plant Biotechnology
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• 제44권4호
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• pp.462-471
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• 2017

Thiamine pyrophosphate (TPP), the active form of thiamine is a cofactor for enzymes involved in central metabolism pathways. However, it is also known to have a role as a stress signaling molecule in response to environmental changes. Anabaena sp. and N. oculata are microorganisms which are abundantly found in Malaysia's freshwater and marine ecosystem. However, not much studies have been done especially in regards to thiamine biosynthesis. This work aimed to amplify of gene transcripts coding for thiamine biosynthesis enzymes besides looking at the expression of thiamine biosynthesis genes upon stress application. Various stress inducers were applied to the cultures and RNA was extracted at different time points. The first two genes, ThiC and ThiG/Thi4 encoding enzymes of the pyrimidine and thiazole branch respectively in the thiamine biosynthesis pathway were identified and amplified. The expression of the genes were analysed via RT-PCR and the intensity of bands were analysed using ImageJ software. The results showed up to 4-fold increase in the expression of ThiC and ThiG gene transcript as compared to control sample in Anabaena sp. ThiC gene in N. oculata showed an expression of 6-fold higher as compared to control sample. In conclusion, stresses induced the expression of the gene coding for one of the most important enzymes in thiamine biosynthesis pathway. This is an agreement with the hypothesis that overexpression of thiamine is crucial in assisting plants to combat abiotic stresses.

• 한국식품과학회지
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• 제30권2호
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• pp.260-265
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• 1998

참깨를 170, 200, $230^{\circ}C$로 열풍순환식과 전기팬에서 볶아서 참유한 기름의 향기 성분을 GC와 GC-MS로 분석하여 동정 확인하고 관능 검사를 실시하였다. 총 33개의 향기성분이 확인 되어졌으며 pyrazine류 14종, thiazole류 7종, pyridine류 4종, oxazole류 2종 및 기타 6종 이였다. 전기팬에서 170, 200, $230^{\circ}C$에서 처리된 시료의 총 향기성분의 함량은 각각 145.29, 334.65, 313.04 ppm 이였고 열풍순환식에서는 각각 28.86, 81.20, 313.28 ppm이 였다. 그리고 개별향기 성분중에서는 pyrazine류의 함량비가 가장 높았다. 6개의 시료에 대한 관능 검사의 결과는 $200^{\circ}C$에서 배전식 방법으로 볶은 참깨로부터 제조된 참기름이 가장 바람직한 향기를 가진것으로 판단되어졌다. 이런 현상은 GC 분석의 결과와 일치하였다.

• Journal of Korean Neurosurgical Society
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• 제40권2호
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• pp.103-109
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• 2006

Objective : Activated endothelial cells mediate the cascade of reactions in response to hypoxia for adaptation to the stress. It has been suggested that hypoxia, by itself, without reperfusion, can activate the endothelial cells and initiate complex responses. In this study, we investigated whether hypoxia-induced endothelial products alter the endothelial permeability and have a direct cytotoxic effect on nerve cells. Methods : Hypoxic condition of primary human umbilical vein endothelial cells[HUVEC] was induced by $CoCl_2$ treatment in culture medium. Cell growth was evaluated by 3,4,5-dimethyl thiazole-3,5-diphenyl tetrazolium bromide [MTT] assay Hypoxia-induced products [$IL-1{\beta},\;TGF-{\beta}1,\;IFN-{\gamma},\;TNF-{\alpha}$, IL-10, IL-6, IL-8, MCP-l and VEGF] were assessed by enzyme-linked immunosorbent assay. Endothelial permeability was evaluated by Western blotting. Results : Prolonged hypoxia caused endothelial cells to secrete IL -6, IL -8, MCP-1 and VEGF. However, the levels of IL -1, IL -10, $TNF-{\alpha},\;TGF-{\beta},\;IFN-{\gamma}$ and nitric oxide remained unchanged over 48 h hypoxia. Hypoxic exposure to endothelial cells induced the time-dependent down regulation of the expression of cadherin and catenin protein. The conditioned medium taken from hypoxic HUVECs had the cytotoxic effect selectively on neuroblastoma cells, but not on astroglioma cells. Conclusion : These results suggest the possibility that endothelial cell derived cytokines or other secreted products with the increased endothelial permeability might directly contribute to nerve cell injury followed by hypoxia.

• Advances in Traditional Medicine
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• 제5권1호
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• pp.21-28
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• 2005

The leaf extracts of Araucaria bidwillii Hook. (Araucariaceae) were evaluated for their cytotoxic effect in various human cancer cell lines. Preliminary investigation by brine shrimp lethality assay indicated that $LC_{50}$ value of various successive extracts were found to be less than $1000\;{\mu}g/ml$, where the ethyl acetate extract showed maximum activity of less than $100\;{\mu}g/ml$. Further cytotoxic evaluation of various leaf extracts of Araucaria bidwilli Hook was carried out in four different human cancer cell lines-acute myeloblastic leukemia (HL-60), chronic myelogenic leukemia (K-562), breast adenocarcinoma (MCF-7) and cervical epithelial carcinoma (HeLa). Cytotoxicity was assessed by trypan blue dye exclusion method and 3-(4,5-dimethyl thiazole-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay. From the present investigation it was found that the ethyl acetate and methanol extract of Araucaria bidwilli Hook was found to be more effective in leukemic cell lines and was less effective in MCF-7 and HeLa. The $IC_{50}$ value of the ethyl acetate extract in leukemic cell lines was found to be $28.18\;and\;34.64\;{\mu}g/ml$ and methanol extract was found to be $33.11\;&\;39.81\;{\mu}g/ml$. It can be concluded that various extract from the leaves of Araucaria bidwillii Hook. posses cytotoxic activity tested in brine shrimps and various human carcinoma cell lines.

• Asian-Australasian Journal of Animal Sciences
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• 제26권5호
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• pp.732-742
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• 2013

Flavour comprises mainly of taste and aroma and is involved in consumers' meat-buying behavior and preferences. Chicken meat flavour is supposed to be affected by a number of ante- and post-mortem factors, including breed, diet, post-mortem ageing, method of cooking, etc. Additionally, chicken meat is more susceptible to quality deterioration mainly due to lipid oxidation with resulting off-flavours. Therefore, the intent of this paper is to highlight the mechanisms and chemical compounds responsible for chicken meat flavour and off-flavour development to help producers in producing the most flavourful and consistent product possible. Chicken meat flavour is thermally derived and the Maillard reaction, thermal degradation of lipids, and interaction between these 2 reactions are mainly responsible for the generation of flavour and aroma compounds. The reaction of cysteine and sugar can lead to characteristic meat flavour specially for chicken and pork. Volatile compounds including 2-methyl-3-furanthiol, 2-furfurylthiol, methionol, 2,4,5-trimethyl-thiazole, nonanol, 2-trans-nonenal, and other compounds have been identified as important for the flavour of chicken. However 2-methyl-3-furanthiol is considered as the most vital chemical compound for chicken flavour development. In addition, a large number of heterocyclic compounds are formed when higher temperature and low moisture conditions are used during certain cooking methods of chicken meat such as roasting, grilling, frying or pressure cooking compared to boiled chicken meat. Major volatile compounds responsible for fried chicken are 3,5-dimethyl-1,2,4-trithiolanes, 2,4,6-trimethylperhydro-1,3,5-dithiazines, 3,5-diisobutyl-1,2,4-trithiolane, 3-methyl-5-butyl-1,2,4-trithiolane, 3-methyl-5-pentyl-1,2,4-trithiolane, 2,4-decadienal and trans-4,5-epoxy-trans-2-decenal. Alkylpyrazines were reported in the flavours of fried chicken and roasted chicken but not in chicken broth. The main reason for flavour deterioration and formation of undesirable "warmed over flavour" in chicken meat products are supposed to be the lack of ${\alpha}$-tocopherol in chicken meat.

• 대한임상검사과학회지
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• 제39권1호
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• pp.19-24
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• 2007

The aim of this study was to evaluate the bacterial effects of Moraxella catarrhalis in otitis media with effusion (OME) by photodynamic therapy (PDT). Bacterial suspensions (10000 CFU/mL) were prepared. The colony forming units (CFU) of Moraxella catarrhalis have been measured after an application of photogem plus 632 nm diode laser irradiation. One ml of the bacterial suspensions have been incubated in the dark for 3h with various concentrations of photogem ($0.625{\sim}5.0_{\mu}g/mL$) and then irradiated with 632 nm diode laser ($15J/cm^2$). After, the PDT Moraxella catarrhalis suspensions ($50{\mu}L$) were inoculated on chocolate agar plate and cultured in the dark at $37^{\circ}C$, 5% $CO_2$ condition for 18h. The colony forming units off the bacteria were measured. Also transmission electron microscopy (TEM) was employed to evaluate the effect of otitis media pathogens by PDT. The nucleus of Moraxella catarrhalis was stained using green fluorescent nucleic acid dye thiazole orange and the fluorescence intensity of the nucleus was measured by flow cytometry. The PDT was effective in killing Moraxella catarrhalis at the photogem dose of $5.0_{\mu}g/mL$, respectively, As assessed by flow cytometry analysis the fluorescence intensity of the nucleus got lower after PDT. TEM result appeared to able to cause damage to the bacterial membranes. On the basis of these findings, bacterial photodynamic therapy with photogem can be considered to be a promising new therapeutic approach for OME.