• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.579-584
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• 2008

A commercial chromogenic agar medium (DFI) was supplemented with glucose (mDFI) to enhance the specificity of Enterobacter sakazakii (E. sakazakit) detection. Escherichia vulneris (E. vulneris), a putative false-positive strain on the DFI medium, produces ${\alpha}$-glucosidase. The enzyme ${\alpha}$-glucosidase hydrolyzes a substrate, 5-bromo-4-chloro-3-indolyl-${\alpha}$, D-glucopyranoside $(X{\alpha}Glc)$, producing green colonies. E. sakazakii strains produced green colonies on both DFI and mDFI agar, whereas E. vulneris produced green colonies on DFI agar but small white colonies on mDFI agar. E. sakazakii and E. vulneris were also readily differentiated by colony color when the mixed culture of the two strains was plated on mDFI agar and incubated for 24 h at $37^{\circ}C$. The results indicate that the selectivity of the commercial chromogenic agar medium could be improved by a simple supplementation with glucose.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.260-267
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• 2006

The Liquid Culture Assay using a recombinant Agrobacterium tumefaciens strain has been developed as a means for quorum sensing autoinducer screening. However, the low aqueous solubility of marine natural product extracts used as potential autoinducers has been a hindrance in the screening process. Although the addition of organic solvents and/or surfactants could increase aqueous solubility, errors in data interpretation including false positive results could be a serious problem. Therefore, determining the best possible solvent and surfactant at the optimum concentration is crucial. Evaluating methanol, ethanol, 1-propanol, DMSO and DMF at concentration ranges of 0~10% revealed < 2% methanol to be most favorable when tested for ${\beta}$-gal activity and growth inhibition of the recombinant A. tumefaciens strain. On the other hand, among surfactants tested, Triton X-100 was similarly effective in increasing the delivery of autoinducers for activity at less than 0.05% concentration.

• International Journal of Advanced Culture Technology
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• v.7 no.2
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• pp.28-33
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• 2019

Electronic health records (EHRs) enable us to use and re-use electronic data for various multiple purposes, such as public reporting, quality improvement, and patient outcomes research. Current hospital-acquired pressure injury (HAPI) risk assessment instruments have not been specifically developed for intensive care unit (ICU) patients and showed false positive rates in this specific populations. Previous research studies report a number of risk factors; however, it is still not clear what factors influence ICU HAPI in this population. As part of a larger research study, we performed an exploratory analysis by using a large electronic health record data. The aims of this study were to compare characteristics of patients who developed HAPIs during their ICU stay with those who did not, and to determine whether the two groups were different in the aspects of length of ICU stay, discharge disposition, and discharge destinations. We conducted chi-square test and t-test for group comparison. Association was examined by using bivariate analyses. Pearson correlation coefficients were used to examine correlation between LOS and number of medications. Our findings suggest a number of consistent and potentially modifiable risk factors, such as sedation, feeding tubes, and the number of medications administered. The mortality of the HAPI group was significantly higher than the non-HAPI group in our data. Discharge disposition was significantly different between the groups. 67% of the HAPI group transferred to intermediate or long-term care hospitals whereas 57.7% of the non-HAPI group went home after discharge. Awareness of these risk factors can lead to clinical interventions that can be preventative in the ICU setting.

• Journal of the Korean Society of Food Culture
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• v.21 no.2
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• pp.209-215
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• 2006

This study had carried out to investigate the usage status of customer, the positive effects and problems, and the most important items of the nutrition labeling at purchasing the food etc. on the current nutrition labeling system in order to establish the customer-centric nutrition labeling system. Survey was carried out by questionnaire method that is targeted on adult female above 20 years old in Seoul and Kyeongnam area from May to June, 2004. For the experience of checking the nutrition label of the processed domestic and imported processed food, 82% and 75.4% of the respondents were replied 'have checked' respectively. For the positive effects due to enforcement of the nutrition labeling system, the respondents agreed highly with 'easy to compare with other products' and 'improve the products quality'. For the problems of the nutrition labeling system, the respondents agreed highly with 'different criteria for each product' and 'incendiary purchasing due to false or exaggerated labeling', and gave the higher scale for the positive effects than the problems relatively. For the necessity of the nutrition labeling system, 96.2% of the respondents were replied 'necessary', and it was indicated a significant difference on age and marital status(p<.01). For the price rising due to enforcement of the nutrition labeling system, 55.2% of respondents agreed, and it was indicated a very significant difference on age and monthly income(p<.001). For the most important nutrition labeling items at purchasing the food, the respondents were replied 'total calorie' on most of the food, and in addition, they checked carefully the lipid, cholesterol, protein, Ca, and Fe.

• Tuberculosis and Respiratory Diseases
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• v.39 no.6
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• pp.517-525
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• 1992

Background: Since its development by Saiki et al, polymerase chain reaction (PCR) has been very useful in various fields of molecular biology. PCR can be used for the detection of a very small amount of microbial agent, and is especially useful in those patients who are difficult to diagnose microbiologically or serologically. Mycobacterium tuberculosis is a very slowly growing organism and AFB staining frequently shows false negative results, and therefore PCR would be a very rapid, easy, and sensitive diagnostic method for the diagnosis of Mycobacterium tuberculosis. Method: To compare PCR with conventional methods in diagnosing Mycobacterium tuberculosis in sputum, we used sputa of patients who visited or were admitted to Seoul National University Hospital. The amplification targets were 383 base pair DNA, a part of 2520 base pair DNA encoding 65 kD Mycobacterium tuberculosis specific protein (the primers are TB-1, -2), and 123 base pair DNA, a part of IS6110 fragment, which multiple copies are known to exsist PCR one genome (the primers are Sal I-1, -2). We also requested AFB staing and culture to the lab of Seoul National University Hospital with the same sample and compared the results. Results: 1) Using TB-1, -2 primers, PCR was positive in 73.1% (19/26) of culture positive sputa, in 12.5% (1/8) of culture negative. but clinically diagnosed tuberculous sputa, and was negative in all sputa of patients who were clinically diagnosed as non-tuberculous etiology. 2) Using Sal I-I, -2 primers, PCR was positive in 94.1% (32/34) of culture positive sputa, in 23.1% (6/26) of culture negative, but clinically diagnosed tuberculous sputa, and was negative in 87.5% (14/16) of sputa from patients who were clinically diagnosed as non-tuberculous etiology. Conclusion: PCR could be a very rapid, sensitive and specific method for the diagnosis of Mycobacterium tuberculosis in sputa, and further studies should be followed for the development of easier method.

• Applied Chemistry for Engineering
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• v.33 no.3
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• pp.235-241
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• 2022

According to the World Water Development Report 2015 released by the United Nations, drinking water is expected to decrease by 40% by 2030. This does not mean that the amount of water decreases, but rather that the water source is contaminated due to environmental pollution. Because microbes are deeply related to water quality, the analysis of microbe is very important for water quality management. While the most common method currently used for microbial analysis is microscopic examination of the shape and feature after cell culture, as the gene analysis technology advances, quantitative polymerase chain reaction (qPCR) can be applied to the microscopic microbiological analysis, and the application method has been studied. Among them, a reverse transcription (RT) step enables the analysis of RNA by RT-PCR. Integrated cell culture (ICC)-qPCR shortens the test time by using it with microbial culture analysis, and viability qPCR can reduce the false positive errors of samples collected from natural water source. Multiplex qPCR for improved throughput, and microfluidic qPCR for analysis with limited amount of sample has been developed In this paper, we introduce the case, principle and development direction of the qPCR method applied to the analysis of microorganisms.

• Tuberculosis and Respiratory Diseases
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• v.50 no.2
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• pp.222-228
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• 2001

Backgrounds : Recent technological developments have introduced a new method to identifying M. tuberculosis complex DNA in clinical samples directly. The direct amplification test (DAT) is approved for identifying M. tuberculosis complex in respiratory specimens that are smear-positive for acid-fast bacilli (AFB). When there is a discrepancy between the AFB smear and DAT, no information on their clinical utility is currently available. In this study, the diagnostic reliability of DAT was investigated in suspected pulmonary tuberculosis patients whose sputum AFB smear was negative. Methods : From June 1, 1998 through May 30, 1999, 909 patients with presumed active pulmonary tuberculosis were enrolled. A sputum AFB stain, culture, DAT and/or biopsy were performed. Using the criteria of clinical tuberculosis or confirmed tuberculosis, the positive predictive value of DAT in diagnosing pulmonary tuberculosis was investigated. Results : The positive predictive value of DAT was 82.1% by the clinically active tuberculosis criteria. However, it decreased to 61.5% when diagnosis was restricted to only to culture positive or biopsy proven cases. The false positive rate of DAT was 18.0%. Conclusion : The DAT is a valuable diagnostic method in suspected patients whose sputum AFB is was negative.

• The Journal of Korean Philosophical History
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• no.39
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• pp.85-114
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• 2013

Traditional values refer to one's attitudes or perspectives developed by negotiating with oneself, others, society, world, nature and universe, which include thoughts on what is right, desirable, and what is dos and don'ts. The purpose of this study was to investigate values which Korean people traditionally emphasized, and their changes by epochal situation focused on the Choson Era. Also, this study intended to assist in finding values and meaning which should be passed down and manifested in contemporary society based on the study results. In this context, I select some positive values in the background of the Joseon dynasty. As traditional values or ethics in Korea destroyed and distorted going through the period of Japanese colonialism, all the existing social culture and traditional culture were denied, which resulted in vanishing common value which led community for several hundred years. The loss of common value caused community destruction and collapse, and made Korean people seek to survival, success and advancement in life as suffering from severe conflict of values. Experience of hollow state of mind caused by historical and cultural severance left distorted and degenerated values to Korea people, which made them pursue false values without realizing true meaning of traditional values. The true meaning of traditional values should be universal no matter how society changes, and could be milestone to contemporary people wandering aimlessly. Realizing and reconsidering the meaning of traditional values to found comtemporary values of Korean people by reflecting on history can produce significant results beyond age-old debate about East or West, and tradition or modernity.

• Clinical and Experimental Pediatrics
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• v.51 no.9
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• pp.971-976
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• 2008

Purpose : Surveillance for detecting and managing latent tuberculosis infection (LTBI) is a key component of tuberculosis control. The classic surveillance tool, the tuberculin skin test (TST), may have some limitations when used in the Bacillus Calmette-$Gu{\acute{e}}rin$ (BCG)-vaccinated population. The object was to perform a blood test $QuantiFERON^{(R)}$-TB Gold In Tube (QFT-G IT) based on the detection of interferon-$\gamma$ ($IFN-{\gamma}$) released by T cells in response to Mycobacterium tuberculosis-specific antigens, and to compare the efficacy of this new diagnostic tool for LTBI with that of TST. Methods : For six months, between October 1, 2006 and April 30, 2007, data were collected from 111 patients under 15 years of age at Severance Children's Hospital. TST and QFT-G IT tests were performed with children with or without contact histories of tuberculosis. In addition to these tests, we examined comparative data from 29 adults who had tuberculosis, to detect false negative rates in the QFT-G IT method. Results : Thirty-three children had household contact histories. In this group, 15% and 42% of cases were found to be positive using the QFT-G IT assay and TST, respectively. Agreement was low between these two tests (${\kappa}=0.39$). In the adult active tuberculosis group, the QFT-G IT false negative rate defined as a positive culture and a negative QFT-G IT result was 12.5%. Conclusion : In diagnosing LTBI in children, the usefulness of a whole-blood $IFN-{\gamma}$ assay employing TB-specific antigens will be revealed only by examining additional longitudinal clinical data; this study serves as a starting point in that process.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2141-2150
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• 2017

This study was conducted to develop a screening method using Colilert-18 and a device for the detection of E. coli from agri-food production environments and fresh vegetables. The specificity and sensitivity of Colilert-18 by temperature ($37^{\circ}C$ and $44^{\circ}C$) were evaluated with 38 E. coli and 78 non-E. coli strains. The false-positive rate was 3.8% (3/78) and 0% (0/78) at $37^{\circ}C$ and $44^{\circ}C$, respectively. The detection limit of E. coli at $37^{\circ}C$ at <1.0 log CFU/250 ml was lower than that at $44^{\circ}C$. The efficiency of the developed device, which comprised an incubator equipped with a UV lamp to detect E. coli in the field, was evaluated by measuring the temperature and UV lamp brightness. The difference between the set temperature and actual temperature of the developed device was about $1.0^{\circ}C$. When applying the developed method and device to various samples, including utensils, gloves, irrigation water, seeds, and vegetables, there were no differences in detection rates of E. coli compared with the Korean Food Code method. For sanitary disposal of culture samples after experiments, the sterilization effect of sodium dichloroisocyanurate (NaDCC) tablets was assessed for use as a substitute for an autoclave. The addition of one tablet of NaDCC per 50 ml was sufficient to kill E. coli cultured in Colilert-18. These results show that the developed protocol and device can efficiently detect E. coli from agri-food production environments and vegetables.