• Parasites, Hosts and Diseases
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• v.53 no.2
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• pp.147-154
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• 2015

Various constituents in clinical specimens, particularly feces, can inhibit the PCR assay and lead to false-negative results. To ensure that negative results of a diagnostic PCR assay are true, it should be properly monitored by an inhibition control. In this study, a cloning vector harboring a modified target DNA sequence (${\approx}375bp$) was constructed to be used as a competitive internal amplification control (IAC) for a conventional PCR assay that detects ${\approx}550bp$ of the Cryptosporidium oocyst wall protein (COWP) gene sequence in human feces. Modification of the native PCR target was carried out using a new approach comprising inverse PCR and restriction digestion techniques. IAC was included in the assay, with the estimated optimum concentration of 1 fg per reaction, as duplex PCR. When applied on fecal samples spiked with variable oocysts counts, ${\approx}2$ oocysts were theoretically enough for detection. When applied on 25 Cryptosporidium-positive fecal samples of various infection intensities, both targets were clearly detected with minimal competition noticed in 2-3 samples. Importantly, both the analytical and the diagnostic sensitivities of the PCR assay were not altered with integration of IAC into the reactions. When tried on 180 randomly collected fecal samples, 159 were Cryptosporidium-negatives. Although the native target DNA was absent, the IAC amplicon was obviously detected on gel of all the Cryptosporidium-negative samples. These results imply that running of the diagnostic PCR, inspired with the previously developed DNA extraction protocol and the constructed IAC, represents a useful tool for Cryptosporidium detection in human feces.

• Parasites, Hosts and Diseases
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• v.59 no.1
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• pp.77-82
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• 2021

As malaria remains a major health problem worldwide, various diagnostic tests have been developed, including microscopy-based and rapid diagnostic tests. LabChip real-time PCR (LRP) is a small and portable device used to diagnose malaria using lab-on-a-chip technology. This study aimed to evaluate the diagnostic performance of LRP for detecting malaria parasites. Two hundred thirteen patients and 150 healthy individuals were enrolled from May 2009 to October 2015. A diagnostic detectability of LRP for malaria parasites was compared to that of conventional RT-PCR. Sensitivity of LRP for Plasmodium vivax, P. falciparum, P. malariae, and P. ovale was 95.5%, 96.0%, 100%, and 100%, respectively. Specificity of LRP for P. vivax, P. falciparum, P. malariae, and P. ovale was 100%, 99.3%, 100%, and 100%, respectively. Cohen's Kappa coefficients between LRP and CFX96 for detecting P. vivax, P. falciparum, P. malariae, and P. ovale were 0.96, 0.98, 1.00, and 1.00, respectively. Significant difference was not observed between the results of LRP and conventional RT-PCR and microscopic examination. A time required to amplify DNAs using LRP and conventional RT-PCR was 27 min and 86 min, respectively. LRP amplified DNAs 2 times more fast than conventional RT-PCR due to the faster heat transfer. Therefore, LRP could be employed as a useful tool for detecting malaria parasites in clinical laboratories.

• Fisheries and Aquatic Sciences
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• v.24 no.11
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• pp.351-359
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• 2021

The red sea bream iridovirus (RSIV) belonging to genus Megalocytivirus is responsible for red sea bream iridoviral disease (RSIVD) in marine and freshwater fishes. Although several diagnostic assays for RSIV have been developed, diagnostic sensitivity (DSe) and specificity (DSp) of real-time polymerase chain reaction (PCR) assays are not yet evaluated. In this study, we developed a TaqMan probe-based real-time PCR method and evaluated its DSe and DSp. To detect RSIV, the probe and primers were designed based on consensus sequences of the major capsid protein (MCP) genes from megalocytiviruses including RSIV, infectious spleen and kidney necrosis virus (ISKNV), and turbot reddish body iridovirus (TRBIV). The probe and primers were shown to be specific for RSIV, ISKNV, and TRBIV-types megalocytiviruses. A 95% limit of detection (LOD_95%) was determined to be 5.3 viral genome copies/µL of plasmid DNA containing the MCP gene from RSIV. The DSe and DSp of the developed real-time PCR assay for field samples (n = 112) were compared with those of conventional PCR assays and found to be 100% and 95.2%, respectively. The quantitative results for SYBR Green and TaqMan probe-based real-time PCR were not significantly different. The TaqMan probe-based real-time PCR assay for RSIV may be used as an appropriate diagnostic tool for qualitative and quantitative analysis.

• Korean Journal of Radiology
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• v.21 no.6
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• pp.684-694
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• 2020

Objective: The purpose was to review the diagnostic performance of the length of tumor capsular contact (LCC) on magnetic resonance imaging (MRI) for detecting prostate cancer extraprostatic extension (EPE). Materials and Methods: PubMed and EMBASE databases were searched up to March 24, 2019. We included diagnostic accuracy studies that evaluated LCC on MRI for EPE detection using radical prostatectomy specimen histopathology as the reference standard. Quality of studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Sensitivity and specificity were pooled and graphically presented using hierarchical summary receiver operating characteristic (HSROC) plots. Meta-regression and subgroup analyses were conducted to explore heterogeneity. Results: Thirteen articles with 2136 patients were included. Study quality was generally good. Summary sensitivity and specificity were 0.79 (95% confidence interval [CI] 0.73-0.83) and 0.67 (95% CI 0.60-0.74), respectively. Area under the HSROC was 0.81 (95% CI 0.77-0.84). Substantial heterogeneity was present among the included studies according to Cochran's Q-test (p < 0.01) and Higgins I² (62% and 86% for sensitivity and specificity, respectively). In terms of heterogeneity, measurement method (curvilinear vs. linear), prevalence of Gleason score ≥ 7, MRI readers' experience, and endorectal coils were significant factors (p ≤ 0.01), whereas method to determine the LCC threshold, cutoff value, magnet strength, and publication year were not (p = 0.14-0.93). Diagnostic test accuracy estimates were comparable across all assessed MRI sequences. Conclusion: Greater LCC on MRI is associated with a higher probability of prostate cancer EPE. Due to heterogeneity among the studies, further investigation is needed to establish the optimal cutoff value for each clinical setting.

• Korean Journal of Radiology
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• v.24 no.8
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• pp.739-751
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• 2023

Objective: This systematic review and meta-analysis evaluated the accuracy of preoperative breast magnetic resonance imaging (MRI) features and tumor-to-nipple distance (TND) for diagnosing occult nipple-areolar complex (NAC) involvement in breast cancer. Materials and Methods: The MEDLINE, Embase, and Cochrane databases were searched for articles published until March 20, 2022, excluding studies of patients with clinically evident NAC involvement or those treated with neoadjuvant chemotherapy. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Two reviewers independently evaluated studies that reported the diagnostic performance of MRI imaging features such as continuity to the NAC, unilateral NAC enhancement, non-mass enhancement (NME) type, mass size (> 20 mm), and TND. Summary estimates of the sensitivity and specificity curves and the summary receiver operating characteristic (SROC) curve of the MRI features for NAC involvement were calculated using random-effects models. We also calculated the TND cutoffs required to achieve predetermined specificity values. Results: Fifteen studies (n = 4002 breast lesions) were analyzed. The pooled sensitivity and specificity (with 95% confidence intervals) for NAC involvement diagnosis were 71% (58-81) and 94% (91-96), respectively, for continuity to the NAC; 58% (45-70) and 97% (95-99), respectively, for unilateral NAC enhancement; 55% (46-64) and 83% (75-88), respectively, for NME type; and 88% (68-96) and 58% (40-75), respectively, for mass size (> 20 mm). TND had an area under the SROC curve of 0.799 for NAC involvement. A TND of 11.5 mm achieved a predetermined specificity of 85% with a sensitivity of 64%, and a TND of 12.3 mm yielded a predetermined specificity of 83% with a sensitivity of 65%. Conclusion: Continuity to the NAC and unilateral NAC enhancement may help predict occult NAC involvement in breast cancer. To achieve the desired diagnostic performance with TND, a suitable cutoff value should be considered.

• The Korean Journal of Cytopathology
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• v.11 no.1
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• pp.19-24
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• 2000

Pulmonary hamartomas are uncommon benign tumors, usually discovered radiologically as a solitary coin lesion in asymptomatic individual. The approach to the patient with a peripheral lung nodule has changed with the increasing acceptance of fine needle aspiration cytology(FNAC) as a rapid, safe, inexpensive, and highly accurate diagnostic tool. However, a few reports describing the FNAC findings of pulmonary hamarioma have appeared in the cytologic literature and the experience of FNAC is limited. We reviewed all 9 cases of pulmonary hamartoma with histologic confirmation after FNAC seen at Asan Medical Center since 1995 to evaluate cytologic findings and to determine the value of FNAC in identifying that lesion. Originally, seven of nine patients were diagnosed as pulmonary hamartoma, while two patients were diagnosed as inflammatory lesion and adenocarcinoma of each. On review, eight of nine patients were considered as diagnostic of pulmonary hamartoma. The diagnostic findings in FNAC of pulmonary hamartoma were the presence of fibrillary myxoid tissue with spindle cells as well as hyaline cartilage.

• Journal of the Korean Home Economics Association
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• v.39 no.7
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• pp.125-144
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• 2001

The purpose of this study is to make a preliminary investigation about the diagnostic process for marital preparation against future divorce which will be necessary for developing tools for the process. Delphi tests have been twice held among 23 professionals regarding the concept of marital diagnosis and the areas of marital preparation to be estimated including definitions of the marital preparation for marriage and the status in which marriage has been prepared, and the categorization of the preparation The result of the study is as follows : Firstly, the concept of marital preparation is comprehensive, for it does include various kinds of preparation necessary for adjustment to marital life except the preparation for wedding ceremony. Secondly, the status in which marriage has been prepared can be divided into individual preparation, a couple's relational preparation, and preparation for marital life. Thirdly, premarital preparation education or counselling will be provided for young persons who are not in status of marital preparation. The areas of marital preparation to be estimated are maturity, independence from parents, and good health in terms of individual preparation, and the depth of love, understanding each other, similarity, harmonization, supplementation, capacity of communication, self-control, and all that sort of thing in terms of relational preparation, sex, views about marriage, information about marital life, role division, giving birth to child and rearing, financial management, and understanding both families of husband and wife.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1042-1045
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• 2003

In this paper, we present a new method for the monitoring of Electric Control Unit's(ECU) self-diagnostic and the sensor signals of vehicle through Web. In order to measure the ECU's self-diagnostic and sensor signals, the interfaced circuit is designed to communicate ECU and terminal according to the ISO, SAE regulation of communication protocol standard. Microprocessor 80C196KC is used for communicating ECU's self-diagnostic signals and the results are sent to the Embedded Linux System(ELS) through RF module. ELS is developed by SA1110, RF module, Embedded Linux. All commands related in ECU communication are executed through Web. The CGI program composed in web server is executed by user and will return sensor signals from ECU Software on Embedded Linux system is developed to monitor the ECU's sensor signals using the arm compiler tool chain in which RS232 port is programmed by half duplex method. The possibility for remote measurement of ECU sensor signal through Web is verified through the developed systems and algorithms.

• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.34-38
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• 2002

Positron emission tomography(PET) is an imaging method that employs radionuclide and tomography techniques. Since 1995, we applied PET not only to the diagnosis of breast cancer but also to the detection of abnormalities in the augmented breast and to the detection of metastasis. Until 2001, we evaluated 242 breast cases by PET at PET center of Seoul National University Hospital. Our group has reported serially at the international journals. In the first report, PET showed high sensitivity for detecting breast cancer, both the primary and axillary node metastasis. A total of 27 patients underwent breast operations based on PET results at Seoul National University Hospital from 1995 to 1996. The diagnostic accuracy of PET were 97% for the primary tumor mass and 96% for axillary lymph node metastasis. In case of the breast augmented, PET also showed excellent diagnostic results for primary breast cancer and axillary lymph node metastasis where mammography and ultrasound could not diagnose properly. PET also had outstanding results in the detection of recurrent or metastatic breast cancer(sensitivity 94%, specificity 80%, accuracy 89%). In addition, our study gave some evidence that PET could be applied further to evaluate the growth rate of tumors by measuring SUV, and finally to prognosticated the disease. PET could also be applied to evaluate the response after chemotherapy to measure its metabolic rate and size. In conclsion, PET is a highly sensitive, accurate diagnostic tool for breast cancer of primary lesion in various conditions including metastasis.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.172-176
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• 2008

FDG PET has been used as a diagnostic tool for localization of seizure focus for last 2-3 decades. In this article, the clinical usefulness of FDG PET in the management of patients with epilepsy has been reviewed, which provided the evidences to justify the medicare reimbursement for FDG PET in management of patients with epilepsy. Literature review demonstrated that FDG PET provides an important information in localization of seizure focus and determination whether a patients is a surgical candidate or not. FDG PET has been reported to have high diagnostic performance in localization of seizure focus in neocortical epilepsy as well as temporal lobe epilepsy regardless of the presence of structural lesion on MRI. Particularly, FDG PET can provide the additional information when the results from standard diagnositic modality such as interictal or video-monitored EEG, and MRI are inconclusive or discordant, and make to avoid invasive study. Furthermore, the presence of hypometabolism and extent of metabolic extent has been reported as an important predictor for seizure free outcome. However, studies suggested that more accurate localization and better surgical outcome could be expected with multimodal approach by combination of EEG, MRI, and functional studies using FDG PET or perfusion SPECT rather than using a single diagnostic modality in management of patients with epilepsy. Complementary use of FDG PET in management of epilepsy is worth for good surgical outcome in epilepsy patients.