• Food Science and Preservation
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• v.13 no.1
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• pp.55-60
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• 2006

Two kinds of composite seasoning products (beef broth powder, polk bone extract powder) were used for a detection trial of gamma irradiation treatment up to 10 kGy by analyzing photostimulated luminescence (PSL), electron spin resonance (ESR) and thermoluminescence(TL). PSL results showed that the photon counts of non-irradiated samples were lower than 700, while those of irradiated samples were higher than 5000, which makes it possible to screen irradiated composite seasoning products at 1 kGy or over from the non-irradiated control. ESR signals measured for both irradiated samples were not irradiation-specific, even though they were dose dependent in the signal intensity. Radiation-induced TL glow curves were found in irradiated beef broth powder and furthernmore, TL ratio $(TL_4/TL_2)$ obtained by a re-irradiation step could verify the detection result of TL1 glow curves, showing ratios lower than 0.05 in the non-irradiated sample and higher than 1.00 in irradiated ones.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.195-198
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• 2006

Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1415-1419
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• 1998

In order to evaluate the safety of greenhouse horticultures, a large number sample sources were collected, and the fungi of Aspergillus sp. and Penicillium sp. were isolated from them. Indirect competitive ELISA method and high performance liquid chromatography (HPLC) were applied to confirm the ochratoxin A producing abilities of isolated strains. One hundred ninety two sample sources including soil, pepper, strawberry and water mellon were collected for fungi isolation from western Gyeongnam, Andong and Gyeongbok. One hundred forty two strains of Aspergillus sp. and one hundred fifty three strains of Penicillium sp. were isolated respectively from them. The isolated fungi were tested for the production of ochratoxin A by ELISA. After culture of them on the modified sucrose low salt medium at $28^{\circ}C$ for 15 days, we found that five strains of Penicillium sp. produced ochratoxin A at the levels of $0.084{\sim}2.128\;{\mu}g/mL$. Among them, #129-2 strain isolated from water melon, showed the highest level of ochratoxin A as $2.128\;{\mu}g/mL$ broth. However, all of isolated Aspergillus sp. didn't produce ochratoxin A. When we compared the results of ELISA method with HPLC method, ochratoxin A production of each isolated strains showed very similar levels.

• 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.

• The Journal of Internal Korean Medicine
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• v.30 no.1
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• pp.153-172
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• 2009

Background : The safety of Korean herbal Medicine (KHM: prescribed herbal medicine by doctors of traditional Korean medicine) is an important issue in Korea. Although both fields. western medicine and traditional Korean medicine. have been studied on the safety of herbs and KHM, their results were not concordance with each other. Objectives : This study aims to review the influence of KHM on liver function in Korean literature systematically. Additionally, we tried to estimate the change of data of liver function test (LFT) and the incidence of liver injury (LI) after the use of KHM. Methods : Systematic literature searches were performed on 4 major databases of Korea from their inception to May 2008. Screening and selection of the studies and the extraction of data were performed independently by two authors. There were no restrictions on the types of publication including grey literatures. Results : Forty studies were included. Only sixteen studies were performed prospectively and fifteen studies collected data from outpatients. Only 8 studies reported the occurrence of LI after the use of KHM. Nineteen cases of LI showed no or mild symptoms and the elevation of LFT was not high. All of LI patients used conventional western drug and KHM concomitantly. and causality of LI was not assessed properly. The incidence of LI related to the use of KHM was estimated as 0.59%-0.76% from all data of these studies. The conflicting results were shown on the change of alanine aminotransferase (ALT) and total bilirubin (TB) after the use of KHM. Conclusions : KHM might be a minor cause of LI in Korea. However the results are not strongly supported as enough to make the safety issue clear because of the limitations of original studies. More rigorous studies are required for answering the safety issue of KHM with the cooperative investigation of both fields of Korean traditional medicine and western medicine.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.334-339
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• 2007

We evaluated the potential of 20 herbal medications (HMs), commonly used in Korea, to inhibit the catalytic activities of several cytochrome P450 (CYP) isoforms. The abilities of 500 ${\mu}g/ml$ of aqueous extracts of 20 HMs to inhibit phenacetin O-deethylation (CYP1A2), coumarin 6-hydroxylation (CYP2A6), bupropion hydroxylation (CYP2B6), rosiglitazone hydroxylation (CYP2C8), tolbutamide 4-methylhydroxylation (CYP2C9), S-mephenytoin 4'-hydroxylation (CYP2C19), dextromethorphan O-demethylation (CYP2D6), chlorzoxazone 6-hydroxylation (CYP2E1), and midazolam 1'-hydroxylation (CYP3A) were tested using human liver microsomes. The HMs Woohwangcheongsimwon suspension and Hwanglyeonhaedok-Tang strongly inhibited CYP2B6 and CYP2D6 isoform activity, respectively. These results suggest that some of the HMs used in Korea have potential to inhibit CYP isoforms in vitro. Although the plasma concentrations of the active constituents of the HMs were not determined, some herbs could cause clinically significant interactions because the usual doses of those individual herbs are several grams of freeze-dried extracts.

• Journal of Dairy Science and Biotechnology
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• v.36 no.4
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• pp.208-219
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• 2018

Emergence of drug resistant strains of Salmonella enterica threatens milk processing and related dairy industries, thereby increasing the need for development of new anti-bacterials. Developments of antibacterial drugs are largely aimed to target the bacterial envelope, but screening their efficacy on bacterial envelope is laborious. This study presents a potential biosensor for envelope-specific stress in which a gfp reporter gene fused to spy gene encoding a periplasmic chaperone protein Spy (spheroplast protein y) that can sense envelope stress signals transduced by two major two-component signal transduction systems BaeSR and CpxAR in Salmonella enterica serovars Enteritidis and S. Gallinarum. Using spy-gfp operon fusions in S. Enterititis and S. Gallinarum, we found that spy transcription in both serovars was greatly induced when Salmonella cells were forming the spheroplast and were treated with ethanol or a membrane-disrupting antibiotic polymyxin B. These envelope stress-specific inductions of spy transcription were abrogated in mutant Salmonella lacking either BaeR or CpxR. Results illustrate that induction of Spy expression can be efficiently triggered by two-component signal transduction systems sensing envelope stress conditions, and thereby suggest that monitoring the spy transcription by spy-gfp operon fusions would be helpful to determine if developing antimicrobials can damage envelopes of S. Enteritidis and S. Gallinarum.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.211-226
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• 2019

Pig CD45, the leukocyte common antigen, is encoded by the PTPRC gene and CD45 is a T cell-type specific tyrosine phosphatase with alternative splicing of its exons. The CD45 is a coordinated regulator of T cell antigen receptor (TCR) signal transduction achieved by dephosphorylating the phosphotyrosine of its substances, including $CD3{\zeta}$ chain of TCR, Lck, Fyn, and Zap-70 kinase. A dysregulation of CD45 is associated with a multitude of immune disease and has been a target for immuno-drug discovery. To characterize its key structural features with the effects of regulating TCR signaling, this study predicted the unknown structure of pig CD45RO (the smallest isoform) and the complex structure bound to the ITAM (REEpYDV) of $CD3{\zeta}$ chain via homology modeling and docking the peptide, based on the known human CD45 structures. These features were integrated into the structural plasticity of extracellular domains and functional KNRY and PTP signature motifs (the role of a narrow entrance into ITAM binding site) of the tyrosine phosphatase domains in a cytoplasmic region from pig CD45RO. This contributes to the selective recognition of phosphotyrosine from its substrates by adjusting the structural stability and binding affinity of the complex. The characterized features of pigCD45RO can be applied in virtual screening of the T-cell specific immunomodulator.

• Parasites, Hosts and Diseases
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• v.58 no.6
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• pp.627-634
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• 2020

Belitung district in Bangka-Belitung Province, Indonesia with a population of 0.27 million is endemic for Brugia malayi and 5 rounds of mass drug administration (MDA) were completed by 2010. Based on the results of 3 transmission assessment surveys (TAS), the district is declared as achieving elimination of lymphatic filariasis (LF) in 2017. The findings of an independent survey conducted by the National Institute of Health Research and Development (NIHRD) in the same year showed microfilaria (Mf) prevalence of 1.3% in this district. In 2019, NIHRD conducted microfilaria survey in 2 villages in Belitung district. Screening of 311 and 360 individuals in Lasar and Suak Gual villages showed Mf prevalence of 5.1% and 2.2% with mean Mf density of 120 and 354 mf/ml in the respective villages. Mf prevalence was significantly higher among farmers and fishermen compared to others and the gender specific difference was not significant. The results of a questionnaire based interview showed that 62.4% of the respondents reported to have participated in MDA in Lasar while it was 57.7% in Suak Gual village. About 42% of the Mf positive cases did not participate in MDA. Environmental surveys identified many swampy areas supporting the breeding of Mansonia vector species. Persistence of infection is evident and in the event of successful TAS3 it is necessary to monitor the situation and plan for focal MDA. Appropriate surveillance strategies including xenomonitoring in post-MDA situations need to be developed to prevent resurgence of infection. Possible role of animal reservoirs is discussed.

• Journal of Korean Clinical Nursing Research
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• v.28 no.2
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• pp.137-145
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• 2022

Purpose: This retrospective chart review study was conducted to examine the frequency of delirium and to identify the risk factors of delirium in elderly surgical patients. Methods: The subjects of this study were 394 patients aged 65 years or older who underwent surgery. The diagnosis of delirium was based on the nursing assessment records with scores from the day of surgery to the 4th day after surgery. The collected data were analyzed by binary logistic regression analysis. Results: The incidence of delirium was 4.3%, and delirium occurred most frequently on the first day of surgery and lasted for 2.16 days on average. Of delirium patients, 76.5% underwent gastrointestinal surgery, and the most common delirium pattern was disorientation. In terms of the characteristics of the subjects, the occurrence of delirium was statistically different by age (𝝌²=10.79, p=.005), systemic-specific disease (𝝌²=9.63, p=.047), use of delirium-inducing drug(benzodiazepine) before surgery (𝝌²=15.90, p<.001), walking ability before surgery (𝝌²=7.65, p=.006), history of delirium (𝝌²=35.92, p<.001), and emergency surgery (𝝌²=16.40, p<.001). As risk factors of delirium, gastrointestinal surgery was found to increase the risk of delirium by 12.57 times (95% CI=2.45~64.46, p=.002), and the use of benzodiazepines before surgery was shown to increase delirium by 10.07 times (95% CI=2.21~45.87, p=.003). Conclusion: It is necessary for nurses to actively evaluate delirium using screening tools for early detection and prevention of delirium in elderly surgical patients with delirium risk factors.