• Journal of Microbiology and Biotechnology
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• 제25권1호
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• pp.66-73
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• 2015

The pabS gene of Agaricus bisporus 02 encoding a putative PABA synthase was cloned, and then the recombinant protein was expressed in Escherichia coli BL21 under the control of the T7 promoter. The enzyme with an N-terminal GST tag or His tag, designated GST-AbADCS or His-AbADCS, was purified with glutathione Sepharose 4B or Ni Sepharose 6 Fast Flow. The enzyme was an aminodeoxychorismate synthase, and it was necessary to add with an aminodeoxychorismate lyase for synthesizing PABA. AbADCS has maximum activity at a temperature of approximately 25℃ and pH 8.0. Magnesium or manganese ions were necessary for the enzymatic activity. The Michaelis-Menten constant for chorismate was 0.12 mM, and 2.55 mM for glutamine. H₂O₂ did distinct damage on the activity of the enzyme, which could be slightly recovered by Hsp20. Sulfydryl reagents could remarkably promote its activity, suggesting that cysteine residues are essential for catalytic function.

• Journal of Microbiology and Biotechnology
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• 제22권10호
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• pp.1412-1422
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• 2012

The aim of this work was to establish the optimal conditions for production of carboxymethylcellulase (CMCase) by a newly isolated marine bacterium using response surface methodology (RSM). A microorganism producing CMCase, isolated from seawater, was identified as Cellulophaga lytica based 16S rDNA sequencing and the neighborjoining method. The optimal conditions of rice bran, ammonium chloride, and initial pH of the medium for cell growth were 100.0 g/l, 5.00 g/l, and 7.0, respectively, whereas those for production of CMCase were 79.9 g/l, 8.52 g/l, and 6.1. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ for cell growth were 6.25, 0.62, 0.28, and 0.42 g/l, respectively, whereas those for production of CMCase were 3.72, 0.54, 0.70, and 0.34 g/l. The optimal temperature for cell growth and the CMCase production by C. lytica LBH-14 were $35^{\circ}C$ and $25^{\circ}C$, respectively. The maximal production of CMCase under optimized condition for 3 days was 110.8 U/ml, which was 5.3 times higher than that before optimization. In this study, rice bran and ammonium chloride were developed as carbon and nitrogen sources for the production of CMCase by C. lytica LBH-14. The time for production of CMCase by a newly isolated marine bacterium with submerged fermentations reduced to 3 days, which resulted in enhanced productivity of CMCase and a decrease in its production cost.

• Journal of Acupuncture Research
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• 제22권3호
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• pp.93-104
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• 2005

2004년 2월말부터 7월말까지 경희의료원 동서 통증센터를 내원한 만성두통환자 92명을 대상으로 8주간 침치료와 침치료에 신경블록요법을 병행 치료하여 다음과 같은 결과를 얻었다. 1. 한방치료군의 경우, VAS 평균수치는 치료 전, 중(4주), 후(8주) 각각 8.50, 5.84, 및 5.50으로 치료 전에 비해 치료 한 달 후부터 유의하게 개선되었다(ANOVA, p<0.05). BPI 점수의 경우 일상생활, 기분, 및 여가생활은 치료 전에 비해 치료 한 달 후부터 유의하게 개선되었으며(p<0.05), 대인관계 및 수면의 경우 치료 전에 비해 치료 두 달부터 유의하게 개선되었다 (p<0.05, Table 2). 2. 동서협진치료군의 경우 VAS 평균수치는 치료 전, 중(4주), 후(8주) 각각 8.26, 4.91, 및 3.60으로 치료 전에 비해 치료 한 달 후부터 유의하게 개선되었다(ANOVA, p<0.05). BPI 점수의 경우 역시 일상생활, 기분, 여가생활, 대인관계, 및 수면 모두 치료 전에 비해 치료 한 달 후부터 유의하게 개선되었다(p<0.05, Table3). 3. 한방치료군과 동서협진치료군 간의 치료 4주와 8주 후의 VAS와 BPI 점수의 변화를 비교 해 보면 치료 4주후는 두 군 간의 차이가 없었으며(p>0.05), 8주 후에는 VAS와 BPI 중 여가생활, 대인관계, 수면에서 EW group이 E group과 비교하여 유의성 있게 개선되었다 (p<0.05, Table 4).

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1153-1157
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• 2011

A kinetic study is reported for aminolysis of S-4-nitrophenyl X-substituted thiobenzoates 3a-g in 80 mol % $H_2O$/20 mol % DMSO at $25.0{\pm}0.1^{\circ}C$. Thiol esters 3a-g are 7.8-47.6 fold more reactive than the corresponding oxygen esters (i.e., 4-nitrophenyl X-substituted benzoates 1a-g). Such reactivity order appears to be in accordance with the expectation that 4-nitrothiophenoxide in 3a-g is a better nucleofuge than 4-nitrophenoxide in 1a-g since the former is 2.64 pKa units less basic than the latter. Hammett plot for the reactions of 3a-g exhibit poor correlation coefficients ($R^2$ = 0.977-0.986) with negative deviation by substrates possessing an electrondonating group (EDG), while the Yukawa-Tsuno plots result in excellent linear correlation ($R^2$ = 0.995-0.997) with ${\rho}$ = 0.93-1.23 and r = 0.57-0.67, indicating that the negative deviation shown by substrates possessing an EDG is caused by ground-state stabilization through resonance interactions but not due to a change in ratedetermining step upon changing the nonleaving-group substituent X. The ${\rho}$ value increases as the incoming amine becomes more basic and more reactive, indicating that the RSP is not operative in the current reactions.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6591-6596
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• 2014

Background: This meta-analysis was performed to investigate the relationship between methylation of the P14 and O6-methylguanine-DNA methyltransferase (MGMT) genes and the risk of hepatocellular carcinoma (HCC). Materials and Methods: We searched PubMed, EMBASE, the Chinese Biomedical Database (CBM), and the China National Knowledge Infrastructure (CNKI) databases to identify relevant studies that analysed HCC tissues for P14 and MGMT gene methylation status; we then performed a meta-analysis. Odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated to evaluate the association between gene methylation and the risk of HCC. Results: Ten studies that assessed P14 gene methylation in 630 HCC tumour tissues and nine studies analysing MGMT methylation in 497 HCC tumour tissues met our inclusion criteria. Our meta-analysis revealed that the rate of P14 methylation was significantly higher in HCCs than in adjacent tissues (OR 3.69, 95%CI 1.63-8.35, p=0.002), but there was no significant difference in MGMT methylation between HCC and adjacent tissues (OR 1.76, 95%CI 0.55-5.64, p=0.34). A subgroup analysis according to ethnicity revealed that P14 methylation was closely related to the risk of HCC in Chinese and Western individuals (Chinese, OR 7.74, 95%CI 1.36-44.04, p=0.021; Western, OR 3.60, 95%CI 1.49-8.69, p=0.004). Furthermore, MGMT methylation was not correlated with the risk of HCC in Chinese individuals (OR 2.42, 95%CI 0.76-7.73, p=0.134). The combined rate of P14 methylation was 35% (95%CI 24-48%) in HCC tumour tissues and 11% (95%CI 4-27%) in adjacent tissues, whereas the combined rate of MGMT methylation was 15% (95%CI 6-32%) in HCC and 10% (95%CI 4-22%) in adjacent tissues. Conclusions: These results suggest that the risk of HCC is related to P14 methylation, but not MGMT methylation. Therefore, P14 gene methylation may be a potential biomarker for the diagnosis of HCC.

• Mycobiology
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• 제47권3호
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• pp.301-307
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• 2019

The $11{\alpha}$-hydroxylation of $16{\alpha}$, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The $11{\alpha}$-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the $11{\alpha}$-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The $H_2O_2$ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the $11{\alpha}$-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

• 생명과학회지
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• 제23권4호
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• pp.542-553
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• 2013

본 연구의 목적은 통계학적 방법을 사용하여 해양미생물 Cellulophaga lytica LBH-14가 생산하는 cellobiase의 생산조건을 확립하는 것이었다. 이 균주의 생육에 최적인 미강, ammonium chloride 및 배지의 초기 pH는 100.0 g/l, 5.00 g/l 및 7.0이었으나, 이 균주가 생산하는 cellobiase의 생산에 최적인 조건은 각각 91.1 g/l, 9.02 g/l 및 6.6이었다. 이 균주의 생육에 최적인 $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$ 및 $(NH_4)_2SO_4$ 등과 같은 배지의 염농도는 각각 6.25, 0.62, 0.28 및 0.73 g/l이었으나, cellobiase 생산에 최적인 염들의 농도는 각각 4.46, 0.36, 0.27 및 0.73 g/l이었다. 또한, 균체의 생육 및 cellobiase의 생산에 최적인 온도는 각각 35 및 $25^{\circ}C$이었다. 플라스크 규모에서 최적화한 조건으로 파이롯트 규모의 생물배양기에서 cellobiase를 생산한 결과, 이 균주가 생산하는 cellobiase의 생산성은 92.3 U/ml이었으며, 이는 최적화하기 전에 비하여 5.4배 향상된 것 이었다. 본 연구를 통하여 쌀 도정공정의 부산물인 미강 및 ammonium chloride를 cellobiase를 생산하는 기질로 개발하였으며 해양 미생물을 사용하여 cellobiase의 생산기간을 7일에서 3일로 단축시켰다. 또한, 본 연구를 통하여 C. lytica LBH-14가 생산하는 cellobiase의 최적 생산조건은 이 균주가 생산하는 CMCase의 최적 생산조건과 다르다는 사실을 확인하였다.

• Journal of Acupuncture Research
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• 제22권3호
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• pp.105-112
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• 2005

경희의료원에 실시하는 임상시험으로 15명의 만성두통환자를 대상으로 침 치료 전후 심박변이도의 변화를 관찰하여 침 치료가 만성두통환자의 자율신경계의 변화에 미치는 영향을 살펴 본 결과 다음의 결론을 얻었다. 1. 치료 전 심박변이도를 관찰한 결과 15명의 치료 전 심박변이도의 경우 SDNN은 $25.78{\pm}7.76$, RMSSD는 $15.16{\pm}6.60$, TP는 $403.23{\pm}240.81$, LF는 $103.38{\pm}91.14$, HF는 $79.43{\pm}61.21$로 남 등이 건강한 성인 206명을 대상으로 심반변이도를 분석한 결과와 비교하여 모든 항목에서 낮게 나타났다. 연령대별로 남 등 의 분석과 비교하여 보면 40대와 50대에서는 LF에서만 높게 나타나고 나머지 항목에서는 모두 낮게 나왔다. 30대 1명은 모든 항목에서, 60대 1명은 LF에서만 높게 나타났고 나머지 항목은 모두 낮게 나왔다. 2. 침치료 8주후의 심박변이도 변화를 치료 전과 비교하여 보면 time domain analysis에서 SDNN과 RMSSD에서 평균수치의 증가는 관찰되었으나 통계적으로 유의하지는 않았다. Frequency donlain analysis에서는 TP, LF, HF에서 모두 평균수치의 증가가 관찰되었으나, TP에서만 통계적으로 유의성 있는 증가 가 있었다(p<0.05, Table3.).

• Imaging Science in Dentistry
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• 제40권1호
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• pp.9-14
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• 2010

Purpose : We evaluated the absorbed doses to the organs and calculated the effective doses when using the digital panoramic radiography. Materials and Methods : The absorbed dose averages in major organs of oral and maxillofacial region were measured using the Dental head phantom (CIRS Co., USA), $^nLi_2B_4O_7$ TLD chip and UD-716AGL dosimeter (Matsushita Electric Industrial Co., JPN) when performing indirect and direct digital panoramic radiography. Effective doses were calculated from correspond to ICRP 2007 recommendations for two panoramic radiography. Results : The absorbed dose average on indirect and direct digital panoramic radiography was highest in parotid glands as measured 1259.6 mGy and 680.7 mGy respectively. Absorbed dose average in another organs were high in order of esophagus, submandibular gland, tongue and thyroid gland on both types of digital panoramic radiography. The absorbed dose average was higher on indirect type than direct one (p<0.05). The effective dose was higher on indirect type than direct one as measured 13.28 mSv and 8.70 mSv respectively. Conclusion : The absorbed doses in salivary gland and oral mucosa were high. However, thyroid gland also demands the attention on radiography due to high tissue weighting factor in spite of the low absorbed dose.

• Environmental Engineering Research
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• 제22권1호
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• pp.19-30
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• 2017

Direct catalysis of vapors from vacuum pyrolysis of biomass was performed on MCM-41 to investigate the effects of operating parameters including catalyzing temperature, catalyzing bed height and system pressure on the organic yields. Optimization of organic phase yield was further conducted by employing response surface methodology. The statistical analysis showed that operating parameters have significant effects on the organic phase yield. The organic phase yield first increases and then decreases as catalyzing temperature and catalyzing bed height increase, and decreases as system pressure increases. The optimal conditions for the maximum organic phase yield were obtained at catalyzing temperature of $502.7^{\circ}C$, catalyzing bed height of 2.74 cm and system pressure of 6.83 kPa, the organic phase yield amounts to 15.84% which is quite close to the predicted value 16.19%. The H/C, O/C molar ratios (dry basis), density, pH value, kinematic viscosity and high heat value of the organic phase obtained at optimal conditions were 1.287, 0.174, $0.98g/cm^3$, 5.12, $5.87mm^2/s$ and 33.08 MJ/kg, respectively. Organic product compositions were examined using gas chromatography/mass spectrometry and the analysis showed that the content of oxygenated aromatics in organic phase had decreased and hydrocarbons had increased, and the hydrocarbons in organic phase were mainly aliphatic hydrocarbons. Besides, thermo-gravimetric analysis of the MCM-41 zeolite was conducted within air atmosphere and the results showed that when the catalyst continuously works over 100 min, the index of physicochemical properties of bio-oil decreases gradually from 1.15 to 0.45, suggesting that the refined bio-oil significantly deteriorates. Meanwhile, the coke deposition of catalyst increases from 4.97% to 14.81%, which suggests that the catalytic activity significantly decreases till the catalyst completely looses its activity.