• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.2052-2059
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• 2017

The emergence and dissemination of Salmonella genomic island 1 (SGI1) are strongly associated with the occurrence of multidrug-resistant (MDR) enterobacteria in humans and animals. Diverse SGI1s have been reported among Salmonella enterica and Proteus mirabilis in several countries. We aimed to characterize SGI1 in P. mirabilis isolates from humans and chickens in Chungcheong Province, Korea. A total of 44 P. mirabilis isolates were recovered from humans (n = 20) and chickens (n = 24). Antimicrobial susceptibility was determined by disk diffusion assay. To detect and characterize SGI1s, PCR amplification and PCR mapping experiments were performed. Repetitive extragenic palindromic-PCR (REP-PCR) was performed to assess the clonality of the isolates. The four P. mirabilis strains (16.7%) from chicken harbored a SGI1, whereas none of the isolates from clinical specimens contained SGI1. The SGI1s detected in our study were all confirmed as SGI1-PmABB harboring aminoglycoside-resistant genes (aacCA5 and aadA7). In P. mirabilis isolates, the presence of SGI1-PmABB was significantly correlated with high resistance rates of the isolates to antimicrobial agents, such as gentamicin, streptomycin, and spectinomycin. Moreover, the four SGI1-bearing isolates showed the same REP-PCR patterns and that suggested both horizontal and clonal spread of the isolates. This study is the first attempt to determine SGI1s in P. mirabilis isolates in Korea. We confirmed that P. mirabilis isolates carrying SGI1-PmABB were distributed at poultry farms in Korea. The present study emphasizes the need for continuous monitoring of SGI1s to prevent spreading of the MDR genomic islands among P. mirabilis isolates from humans and animals.

• 대한의용생체공학회:의공학회지
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• 제5권2호
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• pp.167-172
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• 1984

In the present study, we developed a nuclear stethoscope interfaced with a personal computer (APPLE- II) and evaluated it's performances as compared with the gamma camera. This single-probe, ECG-gated system has been used for displaying the left ventricular time-activity curves, the peak ejection time and its rate, the peak filling time and its rate, and the R-R interval distribution. The radioactivity was measured at every 10msec around the ventricular region, where the activity curves shows the maximal peak to peak variations. The background activity was measured around the lung area showing its counts approximately 50% of the end-diastolic count with minimal variations. The average time-activity curves of 100 beats were used for analysis in the equilibrium study after intravenous injection of 15-20mCi of Tc. The ejection fractions measured by the nuclear stethoscope(Y) were compared with those measured by gamma camera(X) in 47 patients with various heart diseases. The correlation coefficient between two measurements was 0.766 with a relation of Y=1.04 x-8.48. Also, the high reproducibility was obtained for the same patient. Also, the high reproducibility was obtained for the same patient. From this study, we conclude that this device is useful for continuous monitoring in the intensive care unit, as it is portable, compact, and inexpensive.

• 대한의용생체공학회:의공학회지
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• 제41권5호
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• pp.203-209
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• 2020

As the number of people with gait disorders increases, the demand for using wheelchairs increases and the area of a ctivity for people with disabilities expands, thereby they increasing the demand for riding comfortability in various driving environments. Therefore, this study is to develop an entry-level active suspension system that apply to wheelchairs and to evaluate its usability. The suspension applied in this paper consists of a coil spring, a shock absorber, a control module to control the strength of the shock absorber, and a road surface condition monitoring system. A wheelchair occupant secures the riding comfort by adjusting the coil strength of the shock absorber in 12 steps according to various road conditions. Therefore, the mechanical properties were evaluated through the structural analysis of the suspension system, and the tendency toward the magnitude of the road surface vibration attenuated according to the rigidity of the suspension through the vibration test was attempted. In conclusion, as a result of structural analysis of the suspension system, stress in a range lower than the yield strength of the material was generated, and the vibration test showed the effect of attenuating the vibration generated from the road surface when the stiffness of the suspension was adjusted.

• 대한의용생체공학회:의공학회지
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• 제23권4호
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• pp.323-327
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• 2002

만성 당뇨병 질환자는 일 2회 이상 모세혈액을 채취하여 혈당검사를 행함으로써 자신의 혈당 수준을 지속적으로 관리해야 한다. 모세혈액 채취를 위하여 채혈침으로 빈번하게 피부관통을 행해야 하므로 채혈시 뒤따르는 통증은 대단히 중요한 문제이다. 본 연구에서는 기존의 수동 및 자동 채혈침들이 가지는 통증 유발요인들을 모두 최소화하는 기전을 고안하였다. 경사각을 이루는 taper형 스프링, 채혈침을 일관성있는 방향으로 이동시키는 guiding tunnel, 현존하는 기술로 제조할 수 있는 가장 가는 30G 채혈침을 적용함으로써 통증을 최소화 하였다. 침의 침투 깊이를 피하 2mm로 제한하여 통증을 최소화하는 동시에 출혈량을 감소시켰다. 또한 환자 간 감염 및 이차 감염을 방지하기 위하여 사용이 용이한 재사용 방지기전을 설치하였다. 당뇨질환자. 일반인 및 간호실습생들을 대상으로 한 임상실험 결과 통증 및 사용편의성과 안전성 모두 우수한 것으로 입증되었다. 일회 채혈로 모두 성공적인 혈당검사가 가능하였으며 단순한 구조의 소형화 ·일체화된 일회용 자동채혈침의 형태로 구현하였다 본 연구결과는 혈담검사를 위한 모세혈액 채취시 최적의 방법을 제공하였으며 실용성 또한 우수한 것으로 판단되었다.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.2955-2962
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• 2014

Asian ginseng is used as a treatment for cardiovascular diseases, ischemia, and cancers. High mobility group box 1 (HMGB1) protein acts as a late mediator of severe vascular inflammatory conditions. However, the effect of ginsenosides from Asian ginseng on HMGB1-induced inflammatory responses has not been studied. We addressed this question by monitoring the effects of ginsenoside treatment on lipopolysaccharide (LPS) and cecal ligation and puncture (CLP)-mediated release of HMGB1, and HMGB1-mediated regulation of proinflammatory responses. Ginsenoside treatment suppressed LPS-mediated release of HMGB1 and HMGB1-mediated cytoskeletal rearrangements. Ginsenosides also inhibited HMGB1-mediated inflammatory responses. In addition, ginsenosides inhibited the production of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and activation of protein kinase B (Akt), nuclear factor-${\kappa}B$ (NF-${\kappa}B$), and extracellular-regulated kinases (ERK) 1/2 by HMGB1. Ginsenosides also decreased CLP-induced release of HMGB1, production of interleukin (IL) $1{\beta}/6$, and mortality. These results suggested that ginsenosides may be potential therapeutic agents for treatment of vascular inflammatory diseases through inhibition of the HMGB1 signaling pathway.

• 한국의학물리학회지:의학물리
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• 제3권2호
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• pp.43-57
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• 1992

위상감지법(phase detector technique)은 세포의 막 캐패시턴스(membrane capacitance)를 실시간적으로 측정할 수 있는 유일한 방법이나 측정이 행해지는 동안 세포의 상태가 끊임없이 변화하기 때문에 피할 수 없는 측정오차가 존재한다. 본 연구는 이 오차의 근원을 분석하여 위상감지법의 실용한계를 규정하고자 하였다. 이론적 분석에 기초하여 다음과 같은 사실을 밝힐 수 있었다. 1) access conductance와 membrane conductance의 변화에 기인하는 측정오차를 줄이기 위해서는 초기 위상치를 올바로 선택하여야 한다. 2) 이 때 세포를 여기시키기 위해 인가하는 전압의 주파수를 알맞게 선택하여야 한다. 3) 그러나 초기 위상치가 정해진 이후의 위상 변화는 막 캐패시턴스의 측정에 큰 영향을 미치지 않는다. 4) 초기 위상을 적절히 선택하였다 하더라도 세포외 분비시 막 캐패시턴스가 크게 증가하는 경우에는 비례상수에 오차가 발생한다. 이 때 발생하는 오차는 측정기간 동안 비례상수를 되풀이하여(iteration) 보정함으로써 방지할 수 있다. 이상의 결과는 향후 위상감지법을 사용할 때 유용한 설용한계를 제공하리라 생각된다.

• 한국의학물리학회지:의학물리
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• 제17권1호
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• pp.32-39
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• 2006

CT 검사에서 조영제의 혈관외유출을 예방하기 위해 EDA시스템을 증폭기, ADC, 스트레인 게이지로 구성하여 개발하였고, 스트레인 게이지의 신호의 수치를 나타내도록 프로그램을 설계하였다. 신호비율은 500/1000 sec, 분해능 값은 0에서 4,096범위로 표시하고, 입력범위 $0{\sim}5$ V이다. 혈관외유출 검출 문턱 값은 50으로 하였고, 10 간격으로 조정하도록 하였다. 개발된 EDA 시스템을 성인 50명을 대상으로 적용하였다. 2명의 환자에서 혈관외유출이 검출되었고, 조영제 주입속도는 2.0 mL/sec, 2.5 mL/sec, 압력은 137 psi, 158 psi, 혈관외유출된 조영제 용량은 22 mL, 25 mL였다. 설정된 주입 조영제에 비해 20% 정도의 적은 용량이 혈관외유출되었다. 개발된 EDA 시스템은 소량의 조영제를 검출하여 혈관외유출을 예방하는 효과가 있다.

• The Korean Journal of Physiology and Pharmacology
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• 제16권3호
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• pp.205-209
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• 2012

The objective of the present study was to establish the method of measurement of hydrogen peroxide and to estimate the anti-oxidative effect of genistein in the skin. UVB induced skin oxidation and anti-oxidative effect of genistein formulations were evaluated by determining levels of hydrogen peroxide. The mechanism involved in the determination of hydrogen peroxide is based on a color reaction between ferric ion ($Fe^{3+}$) and xylenol orange, often called FOX assay and subsequent monitoring of absorbance values of the reactant at 540 nm. The reaction was to some extent pH-dependent and detection sensitivity was greatest at pH 1.75. Genistein liposomal gel demonstrated better anti-oxidative effect with regard to lowering hydrogen peroxide levels elevated by UVB irradiation compared to genistein-suspended gel. A linear relationship has been observed between anti-oxidative effect of genistein and drug deposition in the skin tissue. Genistein liposomal gel resulting in the localization of the drug in the deeper skin led to improved anti-oxidative effect compared to genistein gel. The suggested method for evaluation of oxidation of the skin can be used as a tool to screen effective anti-oxidative agents and their delivery systems acting on the skin.

• 대한의용생체공학회:의공학회지
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• 제40권6호
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• pp.250-259
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• 2019

Ophthalmic Laser System is widely used in Selective Laser Trabeculoplasty of Open Angle Glaucoma and Ocular Hypertension. Versatile ophthalmic laser system is a medical device with technology that checks the condition of the treatment area by irradiating a continuous laser pulse on the treatment area, and monitoring the microbubble reaction caused by the temperature increase of the melanosome through the ultrasonic signal and the optical signal sensor. It performs selective laser treatment without damaging the photoreceptor by controlling the wavelength of the laser when microbubbles are detected. This study aims to suggest a guideline for evaluating safety, performance and clinical effectiveness of Versatile Ophthalmic Laser System in accordance with the growing technology. International Standards, Regulations, and Clinical Trial Protocols were investigated and analyzed for this study. As a result of this study, the safety, performance and clinical effectiveness test guideline for Versatile Ophthalmic Laser System were proposed. This guideline will ensure the safety and efficacy of Medical device, and furthermore it is expected to be able to promote the development of technology development by supporting a clinical trial plan.

• 폴리머
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• 제31권2호
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• pp.153-159
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• 2007

생분해성 분자 날인 고분자는 바이오센서 약물 전달 등의 생의학적 분야에 적응이 가능하다. 그러므로, 본 연구에서는 생분해성 고분자인 $poly(\varepsilon-caprolactone)$ (PCL) 매크로머를 가교제로 사용하여 theophylline 분자 날인 고분자를 광중합을 통해 제조하고 물성을 조사하였다. PCL 매크로머는 말단에 아크릴기를 갖도록 합성하였으며 FT-IR과 $^1H-NMR$로 확인하였다. PCL 매크로머의 합성수율은 약 78 mol%였다. Theophylline의 제거 및 재결합 실험은 UV/Vis분광기를 이용하여 용액 내 theophylline의 농도를 확인함으로써 이루어졌다. Theophylline분자 날인 고분자의 생분해성 실험을 $37^{\circ}C$의 PBS 용액 내에서 진행한 결과 우수한 생분해성을 보였다.