• Journal of Life Science
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• v.17 no.4 s.84
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• pp.482-492
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• 2007

Infection with Shiga-like toxin (SLT)-producing Escherichia coli causes a spectrum of illnesses with high morbidity and mortality. Host mediators play an important role in the pathogenesis of SLT-I toxicity. We here investigated the effect of SLT-I on tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ production, effect of $TNF-{\alpha}$ on glycolipid globotriaosyleramide (Gb3) expression, and relationship between Gb3 level and differential susceptibility of cells to SLT-I. In this study, we observed that detectable levels of $TNF-{\alpha}$ are produced 6 hrs after induction and continued to increase during 48 hrs by SLT-I. It was also found that Vero cells and dendritic cells expressed high levels of Gb3, 83% and 68%, respectively, and that macrophages had a low level of Gb3 (29%) and showed refractory to cytotoxicity against SLT-I. Vero cells and dendritic cells expressing high levels of Gb3 were highly susceptible to SLT-I. furthermore, macrophages showed a resistance to SLT-I cytotoxicity, despite the fact that Gb3 expression was enhanced. These results suggest that the expression of Gb3 is necessary, but not sufficient to confer sensitivity of macrophages to SLT-I and further underpin the important role of SLT-I and its receptor, Gb3, in the pathogenesis of E. coli O157 infection.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.126-132
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• 2015

Three different methods (simple washing of plastic and pulp sample, washing after direct heating of the diapers, and the heating after washing of plastic and pulp sample) were carried out to decrease total coliforms and heterotrophic plate count (HPC) in the diaper's plastic and pulp. Plastic and pulp samples were obtained from diaper by treatment with 10% $CaCl_2$ and 4% sea salt water, dilution with 1,000 ml tap water, and draining by using sieves. Three times washing was the most appropriate for the reduction of microorganisms in plastic and pulp. By three times washing, the number of total coliforms in the plastic and pulp samples showed 92.8% and 99.8% of decrease, respectively, and the number of HPC showed 97.3% of decrease in the plastic and 98.5% of decrease in the pulp. The washing after direct heating of the fecal contaminated diapers was not effective because HPC in the plastic and pulp samples were still detected about 2-3 log CFU/g in the plastic and 1-2 log CFU/g in the pulp, respectively, even after heating at $60^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$ for 12 h. Meanwhile, total coliforms and HPC were completely sterilized at $80^{\circ}C$ for 4 h by heating after washing of plastic and pulp samples, suggesting that this method was the most appropriate method for the reduction of microorganisms in plastic and pulp obtained from fecal contaminated diapers.

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.377-385
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• 2011

This study was carried out to investigate quality characteristics of dry-cured hams in the domestic market. Two kinds of dry-cured hams were processed with pork leg (T1) and pork neck (T2). Five 24-month dry-cured legs (T1, 5.3-6.1 kg) and twenty 4-month dry-cured pork necks (T2, 1.5-1.9 kg) were used in this experiment. They were stored at $4^{\circ}C$ chilling room and quality characteristics were investigated. Moisture content, water activity, cholesterol content, CIE $L^*$, VBN, total plate counts and lactic acid bacteria of T1 were significantly higher (p<0.05) than those of T2, whereas fat content, ${NO_2}^-$, CIE $a^*$, TBARS and Warner-Bratzler shear force values of T2 were significantly higher (p<0.05) than those of T1. In fatty acid compositions, palmitoleic acid and stearic acid in T2 were significantly higher (p<0.05) than T1, however, oleic and linoleic acid in T2 was significantly lower (p<0.05) than T1. In free amino acids, the total content and individual content of asparagin, leucine and phenylalanine in T1 were higher than those of T2 (p<0.05). The aroma score of T2 was higher than that of T1 in sensory evaluation (p<0.05). In conclusion, two kinds of dry-cured hams were different in their final characteristics and could enhance the consumer's appeal of pork meat in Korean market.

• Journal of Life Science
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• v.19 no.8
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• pp.1039-1046
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• 2009

The cytochrome P450s (P450s) metabolizing natural products are among the most versatile biological catalysts known in plants, but knowledge of the structural basis for their broad substrate specificity has been limited. The activity of p-coumarate 3-hydroxylase (C3H) is thought to be essential for the biosynthesis of lignin and many other phenylpropanoid pathway products in plants however, all attempts to express and purify the protein corresponding C3H gene have failed. As a result, no conditions suitable for the unambiguous assay of the enzyme are known. The detailed understanding of the mechanism and substrate-specificity of C3Hdemands a method for the production of active protein on the milligram scale. We have developed a bacterial expression and purification system for the plant C3H, which allows for the quick expression and purification of active wild-type C3H via introduction of combinational mutagenesis. The modified cytochrome P450 C3H ($C3H_{mod}$) could be purified in the absence of detergent using immobilized metal affinity chromatography and size exclusion chromatography following extraction from isolated membranes in a high salt buffer and catalytically activated. This method makes the use of isotopic labeling of C3H for NMRstudies and X-ray crystallography practical, and is also applicable to other plant cytochrome P450 proteins.

• Journal of Gastric Cancer
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• v.8 no.4
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• pp.237-243
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• 2008

Purpose: Postoperative Infectious complications are recognized as major complications that are associated with surgery. Although many studies have focused on the risk factors of postoperative complications, little is known about the risk factors of infectious complications after gastric cancer surgery, and especially after elective gastrectomy. There is now more and more interest in the risk factors of infectious complications in relation to controlling infection and as indicators of qualitatively assessing infectious complications. The aim of this study was to evaluate the risk factors related with infectious complications after performing elective gastrectomy for treating gastric cancer. Materials and Methods: We retrospectively reviewed a total of 788 patients who had undergone elective gastrectomy for gastric cancer between Jan. 2000 and Dec. 2007. The characteristics of the patients were divided according to the patients' factors and the operations' factors. Results: The patients' mean age was 58.9 (range: 24~91) years; 545 were male and 243 were female. The mean duration of the hospital stay was 20.3 days (range: 5~135 days), the mean operation time was 181.3 minutes (range: 65~440 minutes). The total complication rate was 17.1% (n=135) and the complication rate was 38.5% (n=52) among the 135 patients with infectious complications. The infectious complications were surgical site infection (59.7%), Pneumonia (19.3%), intra-abdominal abscess (11.5%), pseudomembranous colitis (5.7%), bacteremia (1.9%) and hepatic abscess (1.9%). On the univariate analysis, the significant risk factors were male gender, blood transfusion, smoking at the time of diagnosis, alcohol drinking, diabetes mellitus and previous cardiovascular disease (P<0.05 for all). On multivariate analysis that used a logistic regression model, the significant independent risk factors were smoking at the time of diagnosis (OR: 2.877. 95% CI: 1.449~5.713), blood transfusion (OR: 3.440, 95% CI: 1.241~9.534), diabetes mellitus (OR: 3.150, 95% CI: 1.518~6.538), and previous cardiovascular disease (OR: 2.784, 95% CI: 1.4731~5.2539). Conclusion: Pre- or post-operative blood transfusion and the patient's medical history such as previous cardiovascular disease, diabetes mellitus, smoking etc. are the risk factors for infectious complications after undergoing elective gastrectomy for gastric cancer. The patients that have these risk factors need to be treated with great care to prevent infectious disease after elective gastrectomy.

• KIPS Transactions on Computer and Communication Systems
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• v.12 no.5
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• pp.171-180
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• 2023

The three major sleep disorders in Korea are snoring, sleep apnea, and insomnia. Lack of sleep is the root of all diseases. Some of the most serious potential problems associated with sleep deprivation are cardiovascular problems, cognitive impairment, obesity, diabetes, colitis, prostate cancer, etc. To solve these problems, the Korean government provided low-cost national health insurance benefits for polysomnography tests in July 2018. However, insomnia patients still have problems getting treated in terms of time, space, and economic perspectives. Therefore, it would be better for insomnia patients to be allowed to test at home. The measuring device can measure six biosignals (eye movement, tossing and turning, body temperature, oxygen saturation, heart rate, and audio). A gyroscope sensor (MPU9250, InvenSense, USA) was used for eye movement, tossing, and turning. The input range of the sensor was in 258°/sec to 460°/sec, and the data range was in the input range. Body temperature, oxygen saturation range, and heart rate were measured by a sensor (MAX30102, Analog Devices, USA). The body temperature was measured in 30 ℃ to 45 ℃, and the oxygen saturation range was 0% for the unused state and 20 % to 90 % for the used state. The heart rate measurement range was in 40 bpm to 180 bpm. The measurement of audio signal was performed by an audio sensor (AMM2742-T-R, PUIaudio, USA). The was -42 dB ±1 dB frequency range was 20 Hz to 20 kHz. The measured data was successfully received in wireless network conditions. The system configuration was consisted of a PC and a mobile app for bio-signal measurement and data collection. The measured data was collected by mobile phones and desktops. The data collected can be used as preliminary data to determine the stage of sleep and perform the screening function for sleep induction and sleep disturbances. In the future, this convenient sleep measurement device could be beneficial for treating insomnia.

• Food Science and Preservation
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• v.16 no.6
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• pp.915-923
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• 2009

For preparation of high-quality salted mackerel using enzymatic extracts from Ecklonia cava (EEC) to process fresh mackerel caught off Jeju Island, the optimal concentration of EEC was investigated. There were no differences in proximate composition, salinity, Escherichia coli level, pH, volatile basic nitrogen content, histamine level, or peroxide value between salted mackerel samples prepared with different concentrations of EEC. However, the antiradical properties of salted mackerel, assayed by scavenging of DPPH free radicals, hydroxyl radicals, hydrogen peroxide, and alkyl radicals, increased with increasing concentrations of EEC. The optimal concentration of EEC for preparation of high-quality salted mackerel was 2% (w/w). Salted mackerel soaked in 2% (w/w) EEC was superior to commercial salted mackerel in antiradical properties, biogenic amine content, and other relevant chemical properties.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.341-348
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• 2016

This study aimed to develop a microbial process for producing aminolevulinic acid (ALA) using crude glycerol. In the culture of ALA-producing cells (Escherichia coli/pH-hemA) in a medium containing crude glycerol, the cell density and production were 1.8-fold and 1.2-fold lower than those obtained from pure glycerol, respectively. However, the cell growth and production were improved by supplementing the medium with trehalose (30 or 100 g/l). Engineered cells (E. coli/pH-hemA/pS-otsBA) were constructed to express otsBA and their culture performance was compared with that of control cells (E. coli/pH-hemA/ pSTV28). The effects of isopropyl β-D-1-thiogalactopyranoside (IPTG) concentration and the time of induction were examined to improve the cell growth and ALA production in engineered cells cultured using crude glycerol. When 0.6 mM of IPTG was added at the beginning of the exponential growth phase, the ALA produced by cells was 2,121 mg/l, which was comparable to that from pure glycerol. The results demonstrate that otsBA expression endowed cells with the capacity to tolerate the toxicity of crude glycerol for direct use.

• Information and Communications Magazine
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• v.24 no.7
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• pp.26-35
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• 2007

최근 몇 년간 유비쿼터스 서비스를 구현하기 위한 핵심 기술 중 하나인 무선 센서 네트워크에 대한 관심이 높아지고 있다. 무선 센서 네트워크 기술은 물류, 유통, 환경 감시, 홈오토메이션, 군사 분야 등 다양한 분야에 적용 될 수 있기 때문에 앞으로 관련 분야의 시장 또한 커질 것으로 예상되고 있다 [1]. 무선 센서 네트워크는 기존 유선 센서 네트워크나 무선 네트워크 환경과는 많은 차이를 가진다. 우선 극도로 제한된 시스템 자원만을 가질 수 있으며, 열악한 환경 속에서 무선매체를 통해 유기적으로 동작하여야 하는 특징을 가지고 있다. 적게는 수십 개에서 많게는 수백, 수천 개의 자율적인 하드웨어 노드들로 구성되는 무선 센서 네트워크에서 제한된 자원을 효과적으로 활용하기 위해서는 센서 노드에 적합한 운영체제가 필수적으로 요구된다. 지난 몇 년간 센서 노드하드웨어의 발달과 더불어 많은 센서 네트워크용 초소형 운영체제가 개발되어왔다. 현재 많이 알려져 있는 센서 네트워크용 OS로는, 가장 활발한 참여를 보이고 있는 TinyOS[3]부터 SOS[4], MANTIS[5], Contiki[6], T-kernel[7] 등이 있으며, 국내 기술로 개발된 Nano-Qplus[8] 등이 존재한다. 본고에서는 우선 센서 네트워크에 대한 배경 지식과 플랫폼 등에 대한 내용을 간단히 다루고, 본론에서 센서 네트워크용 운영체제가 가져야 할 조건과 현재 개발되어 있는 센서 네트워크 OS들의 특징에 대해 간략히 살펴보도록 하겠다. 또한 센서 네트워크 OS와 밀접한 연관성을 가지는 분야에 대해 간단히 살펴보고, 마지막으로 앞으로의 방향에 대해 알아본다.고려해 볼 때 atlas의 장축의 시계방향 회전은 액티베이터의 사용 효과로 생각되며, 이는 차후 II급 부정교합자에서 액티베이터 치료 효과를 판단하는 또 하나의 지표가 될 수 있다고 생각한다.인해 한반도를 포함한 동아시아 대륙이 태평양판 쪽으로 밀려감으로써 섭입하던 태평양판의 각도가 급해져 동아시아 연변에 강력한 흡입력이 발생하였으며, 이 때문에 태평양판의 운동 방향이 북북서에서 서북서방향으로 회전되었을 가능성이 있다. 따라서 약 51 Ma부터 한반도 동남부에는 지판 경계의 강력한 흡입력으로 동서 내지 서북서-동남동의 인장력이 작동되어 B그룹 암맥군이 관입한 것으로 해석된다.Ledge는 세 군 모두에서 나타나지 않았다. 4. 파일 binding 횟수는 MC군이 가장 적고 PT군이 가장 많았다 (p < 0.05). 이상의 결과를 볼 때, Mtwo 전동 파일을 crown-down technique으로 사용하는 것이 single length technique과 유사한 성형 효율을 보이면서도 더 안전할 것으로 추정된다.고 1명(3%)에서 원격전이를 보였다. 치료 중 급성 합병증으로 11명(37%)에서 RTOG grade 1-2의 장염을 보였으며 1명은 대장의 천공이 발생하여 수술로 치유되었다. 12명(40%)에서 RTOG grade 1-2의 급성 방광염을 보였다. 3명(10%)에서 RTOG grade 1-2의 백혈구 감소증이 보였으며 1명에서 심한 백혈구 감소증(RTOG grade 4)이 나타났으나 회복되어 치료를 완료하였다. 만성 합병증으로 5명(15%)에서 RTOG grade 1-2의 만성 장염을 보였으며 별다른 치료 없이 지내고 있으며

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.1-6
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• 2006

Saccharomyces cerevisiae Dna2 helicase/endonuclease plays an essential role in removing DNA primers during Okazaki fragment processing in eukaryotic DNA replication. Genome-wide scale co-immunoprecipitation experiments predicted that Dna2 interacts with a novel protein YHR122W (1). In this study, we observed that overexpression of YHR122W gene suppressed the temperature-sensitive phenotype of $dna2\Delta405N$ mutation. To investigate direct interaction between these two proteins, a histidine-tagged recombinant YHR122W protein was expressed and purified from E. coli. Physical interaction between the purified YHR122W and Dna2 proteins was detected by enzyme-linked immunosorbent assays. Further more, the complex formation was most efficient at physiological salt concentration, 150 mM NaCl. The genetic and physical interactions between YHR122W and Dna2 shown in this study suggest that the biological functions of these two proteins may be closely related each other.