• Title/Summary/Keyword: negative detector

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Integrated RT-PCR Microdevice with an Immunochromatographic Strip for Colorimetric Influenza H1N1 virus detection

  • Heo, Hyun Young;Kim, Yong Tae;Chen, Yuchao;Choi, Jong Young;Seo, Tae Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.273-273
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    • 2013
  • Recently, Point-of-care (POC) testing microdevices enable to do the patient monitoring, drug screening, pathogen detection in the outside of hospital. Immunochromatographic strip (ICS) is one of the diagnostic technologies which are widely applied to POC detection. Relatively low cost, simplicity to use, easy interpretations of the diagnostic results and high stability under any circumstances are representative advantages of POC diagnosis. It would provide colorimetric results more conveniently, if the genetic analysis microsystem incorporates the ICS as a detector part. In this work, we develop a reverse transcriptase-polymerase chain reaction (RT-PCR) microfluidic device integrated with a ROSGENE strip for colorimetric influenza H1N1 virus detection. The integrated RT-PCR- ROSGENE device is consist of four functional units which are a pneumatic micropump for sample loading, 2 ${\mu}L$ volume RT-PCR chamber for target gene amplification, a resistance temperature detector (RTD) electrode for temperature control, and a ROSGENE strip for target gene detection. The device was fabricated by combining four layers: First wafer is for RTD microfabrication, the second wafer is for PCR chamber at the bottom and micropump channel on the top, the third is the monolithic PDMS, and the fourth is the manifold for micropump operation. The RT-PCR was performed with subtype specific forward and reverse primers which were labeled with Texas-red, serving as a fluorescent hapten. A biotin-dUTP was used to insert biotin moieties in the PCR amplicons, during the RT-PCR. The RT-PCR amplicons were loaded in the sample application area, and they were conjugated with Au NP-labeled hapten-antibody. The test band embedded with streptavidins captures the biotin labeled amplicons and we can see violet colorimetric signals if the target gene was amplified with the control line. The off-chip RT-PCR amplicons of the influenza H1N1 virus were analyzed with a ROSGENE strip in comparison with an agarose gel electrophoresis. The intensities of test line was proportional to the template quantity and the detection sensitivity of the strip was better than that of the agarose gel. The test band of the ROSGENE strip could be observed with only 10 copies of a RNA template by the naked eyes. For the on-chip RT-PCR-ROSGENE experiments, a RT-PCR cocktail was injected into the chamber from the inlet reservoir to the waste outlet by the micro-pump actuation. After filling without bubbles inside the chamber, a RT-PCR thermal cycling was executed for 2 hours with all the microvalves closed to isolate the PCR chamber. After thermal cycling, the RT-PCR product was delivered to the attached ROSGENE strip through the outlet reservoir. After dropping 40 ${\mu}L$ of an eluant buffer at the end of the strip, the violet test line was detected as a H1N1 virus indicator, while the negative experiment only revealed a control line and while the positive experiment a control and a test line was appeared.

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The Effects of a Vasodilator on Transluminal Attenuation Gradient at Coronary Computed Tomography Angiography

  • Moon Sung Kim;Eun-Ju Kang;Hyun Jin Kim;Moo Hyun Kim;Ki-Nam Lee
    • Korean Journal of Radiology
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    • v.21 no.12
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    • pp.1285-1293
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    • 2020
  • Objective: To evaluate the effects of vasodilators on contrast enhancement and transluminal attenuation gradient (TAG) of coronary arteries at coronary computed tomography angiography (CCTA). Materials and Methods: We retrospectively reviewed CCTA scans of patients who underwent double-acquisition CCTA; CCTA without a vasodilator, and CCTA during a intravenous (IV) infusion of nitrate. Among them, we enrolled 19 patients who had no significant atherosclerotic lesions or coronary spasms. In the control group, 28 patients were enrolled who showed normal coronary arteries on CCTA, which was acquired by a conventional method (sublingual vasodilator). We measured the TAG and Hounsfield units for each of the three major epicardial coronary arteries (reported as 'ProxHU') and then compared the results between the nitrate administration methods (CT without vasodilator [CTpre], CT with IV vasodilator [CTiv], and CT with sublingual vasodilator [CTsub]). Results: The mean TAG showed a significant difference between the coronary arteries (right coronary artery [RCA] > left anterior descending artery [LAD] > left circumflex artery [LCX], p < 0.05), while there was no difference in ProxHU of each coronary artery in all three types of nitrate administration methods (p > 0.05). The TAG of CTpre group showed steeper slope than those of vasodilator groups (CTiv and CTsub) on LAD and LCX ([LAD: CTpre = -22.1 ± 6.66, CTiv = -16.76 ± 5.78, and CTsub = -16.47 ± 5.78, p = 0.005], [LCX: CTpre = -31.26 ± 17.43, CTiv = -23.74 ± 14.06, and CTsub = -20.94 ± 12.15, p = 0.051]), while that of RCA showed no significant differences (p = 0.600). When comparing proxHU, CTiv showed higher proxHU than that of CTpre or CTsub, especially on LCX (CTpre = 426.7 ± 68.3, CTiv = 467.9 ± 84.9, and CTsub = 404.9 ± 63.3, p = 0.013). ProxHU showed a negative correlation with TAG on all three of methods (r = -0.280, p < 0.001). Conclusion: TAG in CCTA was significantly affected by vasodilator administration. Both TAG and ProxHU of coronary arteries tend to increase with vasodilator administration on CCTA.

A Wide Dynamic Range CMOS Image Sensor Based on a Pseudo 3-Transistor Active Pixel Sensor Using Feedback Structure

  • Bae, Myunghan;Jo, Sung-Hyun;Lee, Minho;Kim, Ju-Yeong;Choi, Jinhyeon;Choi, Pyung;Shin, Jang-Kyoo
    • Journal of Sensor Science and Technology
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    • v.21 no.6
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    • pp.413-419
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    • 2012
  • A dynamic range extension technique is proposed based on a 3-transistor active pixel sensor (APS) with gate/body-tied p-channel metal oxide semiconductor field effect transistor (PMOSFET)-type photodetector using a feedback structure. The new APS consists of a pseudo 3-transistor APS and an additional gate/body-tied PMOSFET-type photodetector, and to extend the dynamic range, an NMOSFET switch is proposed. An additional detector and an NMOSFET switch are integrated into the APS to provide negative feedback. The proposed APS and pseudo 3-transistor APS were designed and fabricated using a $0.35-{\mu}m$ 2-poly 4-metal standard complementary metal oxide semiconductor (CMOS) process. Afterwards, their optical responses were measured and characterized. Although the proposed pixel size increased in comparison with the pseudo 3-transistor APS, the proposed pixel had a significantly extended dynamic range of 98 dB compared to a pseudo 3-transistor APS, which had a dynamic range of 28 dB. We present a proposed pixel that can be switched between two operating modes depending on the transfer gate voltage. The proposed pixel can be switched between two operating modes depending on the transfer gate voltage: normal mode and WDR mode. We also present an imaging system using the proposed APS.

Analysis of Performance Factor of the Movie-The Handmaiden by Adapting (영화 <아가씨>의 각색에 따른 영화 흥행 요인 분석)

  • Choi, Young-Mi;Jo, I-Un
    • The Journal of the Korea Contents Association
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    • v.17 no.12
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    • pp.417-425
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    • 2017
  • The goal of this study is analysing a box office success of The Handmaiden in terms of modified space-time and character. The movie which has original novel induces desire of watching by decreasing property of experience good of movie based narrative of novel. Contrary to novel that is set in Victorian age, the movie changed contents that make a character who realizes masculine of colonialism and women oppressed by man escape through transcending class by adopting period of Japanese occupation. It hereby decreases negative effect by substituting growth and solidarity of women for the element of homosexuality. Also the gender discussion about crimes against female when the movie was running increases factor of sympathy of characters and accord with subject of the movie. Beside that, The reasons of success are detector, star system of actor, effective public marketing of movie trailer and selection of movie won the award for best picture at a film festival.. Movie through adapting novel enhances ability of various creation and blow up appreciation of spectator. The differentiation of adapted hit movie is that the altered content is creative, has subject that corresponding with universal awareness transcending space-time and expresses property of media effectively.

Determination and survey of fluoroquinolones in meats and eggs (II) (식육 및 계란에서 플루오로퀴놀론계 항균물질 정량분석 및 잔류조사 (II))

  • Choi, Yoon-Hwa;Kim, Yeon-Ju;Lee, Kyung-Hye;Kang, Young-Il;Lee, Jung-Hark
    • Korean Journal of Veterinary Service
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    • v.32 no.3
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    • pp.281-286
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    • 2009
  • Fluoroquinolones in muscle and egg were separated by liquid extraction and determined. The analysis was carried out using following conditions; C18 column ($150{\times}4.6mm$, $5{\mu}m$), mobile phase composed of D.W. (containing 0.4% triethylamine and phosphoric acid) : methanol : acetonitrile (780:100:120, v/v/v), quarternary pump at a flow rate of 0.9ml/min and $20{\mu}l$ of injection volume, fluorescence detector with EX 278nm/Em 456nm. The calibration range of seven fluoroquinolones showed linearity ($r^2{\geq}0.999$) at concentration range of $0.025{\sim}0.8{\mu}g/ml$. The recoveries in fortified muscle and egg represented more than 81.3%. The detection limits for ofloxacin, norfloxacin, ciprofloxacin, enrofloxacin, danofloxacin, saraloxacin and orbifloxacin were 3.1, 2.5, 3.6, 1.7, 0.9, 2.5 and $2.1{\mu}g/kg$, respectively. We also monitored fluoroquinolones residue in the sample (chicken muscle 182, cattle muscle 140, pig muscle 139, egg 212) using EEC-plate (E. coli ATCC 11303) screening and HPLC confirmation methods. The screening test results, fluoroquinolones, antibacterial substances were all negative.

SNPs of Excision Repair Cross Complementing Group 5 and Gastric Cancer Risk in Chinese Populations

  • Yang, Wan-Guang;Zhang, Shan-Feng;Chen, Ju-Wu;Li, Li;Wang, Wan-Peng;Zhang, Xie-Fu
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6269-6272
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    • 2012
  • We conducted a case-control study to determine the association between several potential SNPs of excision repair cross complementing group 5 (XPG) and gastric cancer susceptibility, and roles of XPG polymorphisms in combination with H.pylori infection in determining risk of gastric cancer. In our study, we collected 337 newly diagnosed gastric cancer cases and 347 health controls. Three SNPs of XPG, rs2296147T>C, rs2094258C>T and rs873601G>A, were genotyped using the Taqman real-time PCR method with a 7900 HT sequence detector system. H. pylori infection was diagnosed by ELISA. By multivariate logistic regression analysis, the rs2296147 CC genotype was associated with a decreased risk of gastric cancer (OR=0.52, 95% CI=0.27-0.97), and rs2094258 TT was associated with elevated risk (OR=2.13, 95% CI=1.22-3.35). Positive H.pylori individuals with rs2094258 TT genotypes demonstrated increased risk of gastric cancer (OR=2.13, 95% CI=1.22-3.35), while rs2296147 CC was associated with lower risk among patients with negative H.pylori (OR=0.45, 95%CI=0.22-0.89). Our findings suggested that XPG polymorphisms might contribute to risk of gastric cancer among Chinese populations, but the effect needs to be further validated by larger sample size studies.

Is Lymph Node Size a Reliable Factor for Estimating Lymph Node Metastasis in Early Gastric Cancer?

  • Kim, Dong Jin;Kim, Wook
    • Journal of Gastric Cancer
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    • v.18 no.1
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    • pp.20-29
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    • 2018
  • Purpose: Pre-operative lymph node (LN) size is a valuable parameter for determining treatment strategy for gastric cancer. However, a correlation between LN size and metastasis has not been established. Materials and Methods: Thirty-six LN-positive (LNP) and matched 36 LN-negative (LNN) patients were included, and pathology slides of the LNs of these patients were reviewed. All the LNs were measured along the long-axis (LA) and short-axis (SA), manually. Results: Average retrieved LNs were $37.3{\pm}19.8$ and $40.5{\pm}11.6$ in the LNN and LNP groups, respectively. In total 2,800 LNs, including 136 metastatic LNs (MLNs) and 2,664 non-metastatic LNs (nMLNs), were evaluated. Mean length was significantly more in MLNs along both, the LA and SA (MLN_LA vs. nMLN_LA: $4.97{\pm}3.84$ vs. $3.37{\pm}2.40mm$, MLN_SA vs. nMLN_SA: $3.86{\pm}3.19$ vs. $2.43{\pm}1.59mm$; P<0.001). However, 92.6% (126/136) and 95.6% (130/136) of MLNs were <10 mm along the LA and SA, respectively. In addition, only 22.2% of the LNP group exhibited an MLN as the largest LN. Conclusions: Pre-operative multi-detector computed tomography has limited ability in estimating the presence of metastasis in LNs because most MLNs are less than 10 mm, and only a small proportion of the LNP group exhibits an MLN as the largest MLN.

Percutaneous Sacroplasty : Effectiveness and Long-Term Outcome Predictors

  • Lee, Jaehyung;Lee, Eugene;Lee, Joon Woo;Kang, Yusuhn;Ahn, Joong Mo;Kang, Heung Sik
    • Journal of Korean Neurosurgical Society
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    • v.63 no.6
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    • pp.747-756
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    • 2020
  • Objective : To evaluate the effectiveness and long-term outcome predictors of percutaneous sacroplasty (PSP). Methods : This single-center study assessed 40 patients with sacral insufficiency fractures using the short-axis technique under C-arm flat-panel detector computed tomography (CT). Two radiologists reviewed the patients' magnetic resonance and CT images to obtain imaging findings before PSP and determine technical success, respectively. The short-term outcomes were visual analog scale score changes and opioid usage reductions. Long-term outcomes were determined using telephone interviews and the North American Spine Society (NASS) patient-satisfaction index at least one year after PSP. Results : Technical success was achieved without any significant complications in 39 patients (97.5%). Telephone interviews were possible with 12 patients and failed in 10 patients; death was confirmed in 18 patients. Fifteen patients (50%) re-visited the hospital and received conservative treatment, including spinal injections. Nine patients reported positive satisfaction (NASS patient-satisfaction index 1 or 2), while the negative satisfaction group (NASS patient-satisfaction index 3 or 4, n=3) showed a higher incidence of compression fractures at the thoracolumbar spine level (66.7% vs. 22.2%) and previous spinal injection history (66.7% vs. 33.3%). The poor response group also showed higher incidences of facet joint arthrosis (100% vs. 55.6%), central canal stenosis (100% vs. 22.2%), neural foraminal stenosis (33.3% vs. 22.2%), scoliosis (100% vs. 33.3%), and sagittal malalignment (100% vs. 44.4%). Conclusion : PSP was effective for sacral insufficiency fractures and showed good long-term outcomes. Combined compression fractures in the thoracolumbar spine and degenerative lumbar pathologies could be possible poor outcome predictors.

In vitro Biofumigation of Brassica Tissues Against Potato Stem Rot Caused by Sclerotinia sclerotiorum

  • Ojaghian, Mohammad Reza;Jiang, Heng;Xie, Guan-Lin;Cui, Zhou-Qi;Zhang, Jingze;Li, Bin
    • The Plant Pathology Journal
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    • v.28 no.2
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    • pp.185-190
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    • 2012
  • Sclerotinia sclerotiorum is a serious pathogen which causes yield loss in many dicotyledonous crops including potato. The objective of this study was to assess the potential of biofumigation using three Brassica crops including Brassica napus, B. juncea and B. campestris against potato stem rot caused by S. sclerotiorum by in vitro tests. Both macerated and irradiated dried tissues were able to reduce radial growth and sclerotia formation of five pathogen isolates on PDA, but macerated live tissues were more effective. Compared with other tested crops, B. juncea showed more inhibitory effect against the pathogen. The volatile compounds produced from macerated tissues were identified using a gas chromatograph-mass spectrometer. The main identified compounds were methyl, allyl and butyl isothiocyanates. Different concentrations of these compounds inhibited mycelial growth of the pathogen in vitro when applied as the vapor of pure chemicals. A negative relationship was observed between chemicals concentrations and growth inhibition percentage. In this study, it became clear that the tissues of local Brassica crops release glucosinolates and have a good potential to be used against the pathogen in field examinations.

Bioequivalence Evaluation of Two Brands of Cefixime 100 mg Capsule (Suprax and Alpha-Cefixime) in Korean Healthy Volunteers

  • Choi, Dong-Hyun;Burm, Jin-Pil
    • Biomolecules & Therapeutics
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    • v.15 no.3
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    • pp.182-186
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    • 2007
  • Cefixime is an orally absorbed cephalosporin with a broad spectrum of activity against Gram-negative bacteria and is highly resistant to beta-lactamase degradation. The purpose of the present study was to evaluate the bioequivalence of two cefixime capsules, Suprax capsule (Dong-A Pharmaceutical Co., reference drug) and Alpha-Cefixime capsule (Alpha Pharmaceutical Co., test drug), according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty-four normal subjects, $23.5{\pm}3.72$ years in age and $68.3{\pm}8.89$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. There was one week washout period between the doses. After one capsule containing 100 mg of cefixime was orally administered, plasma was taken at predetermined time intervals and the concentrations of cefixime in plasma were determined using HPLC with UV detector. The pharmacokinetic parameters such as $AUC_{t}$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_{t}$, $C_{max}$ and $T_{max}$ between two products were -3.91%, -2.23% and -3.18%, respectively, when calculated against the reference drug. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of $log0.8{\leq}{\delta}{\leq}log1.25$ (e.g., $log0.8786{\leq}{\delta}{\leq}log1.0523$ and $log0.8889{\leq}{\delta}{\leq}log1.0512$ for $AUC_{t}$ and $C_{max}$, respectively). The 90% confidence intervals using untransformed data was within ${\pm}20%$(e.g., $-10.37%{\leq}{\delta}{\leq}6.73%$ for $T_{max}$). All parameters met the criteria of KFDA for bioequivalence, indicating that Alpha-Cefixime capsule (Alpha Pharmaceutical Co.) is bioequivalent to Suprax capsule (Dong-A Pharmaceutical Co.).