• Journal of the Korean Society of Visualization
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• v.13 no.1
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• pp.35-42
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• 2015

CD4+ T-cell count determines the effectiveness for antiretroviral therapy (ART) in patients with human immunodeficiency virus (HIV). Although ART slows the progression of HIV to AIDS, rapid counting of CD4+ T lymphocytes with a drop of patient's blood sample is urgently needed to ensure timely ART treatment in rural areas. Recently point-of-care CD4 testing devices have been developed by using non-flow based imaging cytometer incorporated with a sample cartridge where CD4+ T cells are reacted with fluorescently tagged specific antibodies. Here we conducted an experimental study using a conventional fluorescence microscope-based imaging system to quantitate the interaction of CD4 antibodies with CD4+ T cells at different reaction conditions. We demonstrated that a fast and affordable point-of-care CD4 test is feasible with a far less amount of antibodies and a shorter incubation time compared with a conventional sample preparation protocol for flow cytometry. We also proposed a general method to evaluate and compare the detection limit across different CD4 counting platforms by using fluorescently labelled microbeads for intensity calibration.

• Journal of Veterinary Clinics
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• v.37 no.1
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• pp.23-27
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• 2020

Between May and November 2018, babesiosis was examined in 162 bloods samples obtained to an animal hospital in Jeju island for anemia and medical examination. Sixty-two of 162 (38.3%) were positive by PCR. The ultra fast real-time PCR test with blood directly analyzed without DNA extraction showed the same results. Accurate diagnosis, treatment and prognosis of babesiosis should be combined with clinical symptoms, blood tests, the babesia antibody test, and the PCR antigen test. Ultra fast real-time PCR, with these tests, is expected to be a point-of-care testing (POCT) for easy, fast and accurate diagnosis of babesiosis in the veterinary clinic.

• Ceramist
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• v.21 no.3
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• pp.293-301
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• 2018

Paper-based analytical devices (${\mu}PAD$) are highly advantageous for portable diagnostic systems owing to their low costs and ease of use. ${\mu}PADs$ are considered as the best candidates for realizing the World Health Organization (WHO) ASSURED criteria: affordable, sensitive, specific, user-friendly, rapid and robust, equipment-free, and deliverable to end users. However, they have several limitations such as low sensitivity and accuracy. This article reports a mini review for a micro-fluidic paper-based analytical devices (${\mu}PAD$), especially for addressing low sensitivity and accuracy issues.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.1
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• pp.132-148
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• 2013

Via the Internet, the information infrastructure of modern health care has already established medical information systems to share electronic health records among patients and health care providers. Data hiding plays an important role to protect medical images. Because modern medical devices have improved, high resolutions of medical images are provided to detect early diseases. The high quality medical images are used to recognize complicated anatomical structures such as soft tissues, muscles, and internal organs to support diagnosis of diseases. For instance, 16-bit depth medical images will provide 65,536 discrete levels to show more details of anatomical structures. In general, the feature of low utilization rate of intensity in 16-bit depth will be utilized to handle overflow/underflow problem. Nowadays, most of data hiding algorithms are still experimenting on 8-bit depth medical images. We proposed a novel reversible data hiding scheme testing on 16-bit depth CT and MRI medical image. And the peak point and zero point of a histogram are applied to embed secret message k bits without salt-and-pepper.

• Analytical Science and Technology
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• v.20 no.5
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• pp.393-399
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• 2007

In principle, the blood galactose level may be determined conveniently with a strip-type biosensor similar to that for glucose. In this study, we describe the development of a disposable galactose biosensor strip for point-of-care testing. The sensor strip is constructed with screen-printed carbon paste electrode (SPCE) and sample amount (< $100{\mu}L$). The developed strip the galactose level in less than 90 s using bienzymatic system of galactose oxidase (GAO) and horseradish peroxidase (HRP). The effects of pH, mediator (1,1-ferrocenedimethanol) concentration, ratio of enzymes, and applied potential were determined preliminarily with glassy carbon electrodes, and optimized further with the strip-type electrodes. The sensor exhibits linear response in the range of $0{\sim}400{\mu}M$ ($r^2$ = 0.997, S/N = 3). Since a low working potential, in principle, the fabricated disposable galactose biosensor has -100 mV (vs. Ag/AgCl), it is applied for the detection of galactose, interfering responses from common interferents such as ascorbic acid, uric acid and acetaminophen could be minimized. The sensor has been used to determine the total galactose level in standard samples with satisfactory reproducibility (CV = 5 %).

• The Korean Journal of Health Service Management
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• v.11 no.2
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• pp.1-15
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• 2017

Objectives : This study aimed to identify the perception of quality improvement in health care and operational performance after the implementation of the Healthcare Accreditation. Methods : Data were collected from 5 hospitals that have experienced the 2th Healthcare Accreditation in Busan, South Korea. A Likert 5-point scale was used to measure the research variables and a structured questionnaire was used. Finally, 206 valid cases were analyzed using SPSS win 18.0. For hypothesis testing, hierarchical multiple regression analysis were performed. Results : The perception of quality improvement in health care after the implementation of the Healthcare Accreditation was higher than the operational performance. In the customer orientation and job performance, the perception of quality improvement in health care and operational performance had a significant influence. Conclusions : It is necessary to use the Healthcare Accreditation as a virtuous cycle of management that can ensure enforcement of workplace regulations and improve the members'ability to provide high quality medical services.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.201-204
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• 2003

Plasma lipoproteins transporting cholesterol through blood vessels are divided into three major classes, VLDL, LDL, and HDL. The ratio of HDL cholesterol over the total can be used as an indicator for prognosis of coronary artery diseases. In this study, we have developed two analytical systems for %HDL cholesterol with different flow modes toward gravity and analyzed them for their characteristics and performances.

• Journal of the Korean Electrochemical Society
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• v.27 no.1
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• pp.1-7
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• 2024

With the increasing demand for wearable sensors that are capable of point-of-care testing, paper-based sensors have been extensively studied. Paper is not only extremely cost-effective but also lightweight and flexible, and it is easy to apply conductive materials such as carbon and hydrophobic substances like wax to its surface. Moreover, the capillary action caused by cellulose fibers in paper allows the flow of liquid without help from external forces, making paper a particularly promising platform for wearable electrochemical sensors. Accordingly, paper-based sensors for detecting various analytes through electrochemical methods have been actively developed. Recently, paper-based electrochemical sensors that utilize electrochemiluminescence (ECL) or electrochromic materials for the optical read-out have been reported. This review introduces the basic fabrication methods and various application strategies of paper-based electrochemical sensors.

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.3
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• pp.19-28
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• 2015

With the aim of developing a smartphone-based point-of-care device that is small, inexpensive, and easy to handle by non-expert, we designed a fluorescence smartscope for counting particles and a DC motor-controlled particle positioning system. Our smartscope can count the number of fluorescent particles and fluorescently-stained white blood cells through a phone camera with an adaptor containing a LED, a ball lens and optical filters and an application running on a smartphone. The motor was controlled wirelessly via Bluetooth with an Android smartphone. We found that axial spinning of a helical microfluidic channel allows arrangement of particles having size similar to the white blood cells. The motor-controlled particle positioning system can minimize time-consuming manual processes and automate sample preparation process and thus, if integrated with the smartscope, it can be used for a point-of-care testing device based on a smartphone.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.108-112
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• 2011

In clinical settings, researchers often want to assess agreement between two measurements (or tests) of the same continuous variable. For example, when new point-of-care analyzer for testing blood glucose level were introduced clinicians need to compare results from standard or established laboratory method of measurement to those of new or point-of-care analyzer. The question in a method-comparison study would either of two different methods be used to measure the same variable equivalently. In this paper common misuse of statistical methodologies seen in the medical literatures such as correlation coefficient and paired t-test are discussed. The Bland-Altman technique has been widely used for this purpose and provides a graphic in presentation of the findings from a method-comparison study, with a mean value of measurement, this bias and the limits of agreement. For ease of application and interpretation of this technique we discussed the analysis procedure and illustrated with two worked examples. Finally, a number of alternative ways in which data can be analysed and reported in such studies were reviewed.