• Genomics & Informatics
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• v.21 no.4
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• pp.52.1-52.10
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• 2023

Accurate and efficient microbial diagnosis is crucial for effective molecular diagnostics, especially in the field of human healthcare. The gold standard equipment widely employed for detecting specific microorganisms in molecular diagnosis is quantitative real-time polymerase chain reaction (qRT-PCR). However, its limitations in low metagenomic DNA yield samples necessitate exploring alternative approaches. Digital PCR, by quantifying the number of copies of the target sequence, provides absolute quantification results for the bacterial strain. In this study, we compared the diagnostic efficiency of qRT-PCR and digital PCR in detecting a particular bacterial strain (Staphylococcus aureus), focusing on skin-derived DNA samples. Experimentally, specific primer for S. aureus were designed at transcription elongation factor (greA) gene and the target amplicon were cloned and sequenced to validate efficiency of specificity to the greA gene of S. aureus. To quantify the absolute amount of microorganisms present on the skin, the variable region 5 (V5) of the 16S rRNA gene was used, and primers for S. aureus identification were used to relative their amount in the subject's skin. The findings demonstrate the absolute convenience and efficiency of digital PCR in microbial diagnostics. We suggest that the high sensitivity and precise quantification provided by digital PCR could be a promising tool for detecting specific microorganisms, especially in skin-derived DNA samples with low metagenomic DNA yields, and that further research and implementation is needed to improve medical practice and diagnosis.

• The Korean journal of internal medicine
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• v.39 no.3
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• pp.469-476
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• 2024

Background/Aims: The reimbursement policy for cryptogenic stroke (CS) was expanded in November 2018 from recurrent strokes to the first stroke episode. No reports have demonstrated whether this policy change has affected trends in implantable loop recorder (ILR) utilization. Methods: We identified patients who received an ILR implant using the Korea Health Insurance Review and Assessment Service database between July 2016 and October 2021. Patients meeting all the following criteria were considered to have CS indication: 1) prior stroke history, 2) no previous history of atrial fibrillation or flutter (AF/AFL), and 3) no maintenance of oral anticoagulant for ≥4 weeks within a year before ILR implant. AF/AFL diagnosed within 3 years after ILR implant or before ILR removal was considered ILR-driven. Results: Among 3,056 patients, 1,001 (32.8%) had CS indications. The total ILR implant number gradually increased for both CS and non-CS indications and the number of CS indication significantly increased after implementing the expanded reimbursement policy. The detection rate for AF/AFL was 26.3% in CS patients over 3 years, which was significantly higher in patients implanted with an ILR within 2 months after stroke than those implanted later. Conclusions: The expanded coverage policy for CS had a significant impact on the number of ILR implantation for CS indication. The diagnostic yield of ILR for AF/AFL detection seems better when ILR is implanted within 2 months than later. Further investigation is needed to demonstrate other clinical benefits and the optimal ILR implantation timing.

• Tuberculosis and Respiratory Diseases
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• v.40 no.5
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• pp.565-574
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• 1993

Background: Pulmonary hamartomas are benign tumors that occur in the parenchyma or in the bronchi. They present as a solitary pulmonary nodule(SPN) or as a cause of bronchial obstruction. The incidence, once minimal, is increasing in Korea. To get clinical spectrum about the tumor, we analyzed all the reported cases in Korea since 1964. Methods: We reviewed the clinical, radiological and pathological findings of 13 patients of intrapulmonary or endobronchial hamartomas in Severance Hospital and of 38 reported cases in Korea published in literatures from 1964 to 1992 retrospectively. Results: Including 17 endobronchial hamartomas, 54 cases were studied. There were 25 men and 29 women, with a mean age of 47.2 years; 45.3 years in endobronchial type and 51.3 years in parenchymal type. Pulmonary symptoms were present in 8 patients (22%) of intrapulmonary type and in all patients of endobronchial type: cough (65%), dyspnea (53%), sputum (35%), fever (29%) in order. On chest X-rays, atelectasis was seen in 10 patients (59%) in endobronchial type; but SPN was noted in 36 patients (97%) of intrapulmonary type. Calcification was present in 7 intapulmonary hamartomas (23%); but is in 2 endobronchial hamartomas (12%). The diagnostic yield was 6 out of 14(43%) in endobronchial ones; 4 out of 7(57%) in intrapulmonary ones. Fifty patients underwent operations as follows: lobectomy (28), enucleation (8), resection (8), bilobectomy (4), pneumonectomy (2). The hamartomas were 1.2 times more common in the right lung; mean transverse diameter at the time of operation was 2.3 cm in endobronchial type, 3.8 cm in intrapulmonary ones. Chondroid components were present in 11(65%) of 17 endobronehial ones but in 30(91%) of 33 intrapulmonary hamartomas. No malignant changes were seen perioperative period and up to early 1993. Conclusion: The younger age in endobronchial hamartomas, the preponderance of the female sex and the more incidence in the right lung, and the diagnostic choice of lobectomies were different from the studies of the Western countries.

• Tuberculosis and Respiratory Diseases
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• v.43 no.4
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• pp.500-518
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• 1996

Background : The solitary pulmonary nodule(SPN) presents a diagnostic dilemma to the physician and the patient. Many clinical characteristics(i.e. age, smoking history, prior history of malignancy) and radiological characteristics( i.e. size, calcification, growth rate, several findings of computed tomography) have been proposed to help to determine whether the SPN was benign or malignant. However, most of these diagnostic guidelines are based on the data collected before computed tomography(CT) has been introduced and lung cancer was not as common as these days. Moreover, it is not well established whether these guidelines from western populations could be applicable to Korean patients. Methods : We had a retrospective analysis of the case records and radiographic findings in 114 patients presenting with SPN from Jan. 1994 to Feb. 1995 in Seoul National University Hospital, a tertiary referral hospital. Results : We observed the following results ; (1) Out of 113 SPNs, the etiology was documented in 94 SP IS. There were 34 benign SP s and 60 malignant SPNs. Among which, 49 SPNs were primary lung cancers and the most common hi stologic type was adenocarcinoma. (2) The average age of patients with benign and malignant SPNs was $49.7{\pm}12.0$ and $58.1{\pm}10.0$ years, respectively( p=0.0004), and the malignant SPNs had a striking linear propensity to increase with age. (3) No significant difference in the hi story of smoking was noted between the patients with benign SPNs($13.0{\pm}17.6$ pack- year) and those with malignant SPNs($18.6{\pm}25.1$ pack-year) (p=0.2108). (4) 9 out of 10 patients with prior history of malignancy had malignant SPNs. 5 were new primary lung cancers with no relation to prior malignancy. (5) The average size of benign SPNs($3.01{\pm}1.20cm$) and malignant SPNs($2.98{\pm}0.97cm$) was not significantly different(p=0.8937). (6) The volume doubling time could be calculated in 22 SPNs. 9 SPNs had the volume doubling time longer than 400 days. Out of these, 6 were malignant SPNs. (7) The CT findings suggesting malignancy included the lobulated or spiculated border, air- bronchogram, pleural tail, and lymphadenopathy. In contrast, calcification, central low attenuation, cavity with even thickness, well-marginated border, and peri nodular micronodules were more suggestive for benign nodule. (8) The diagnostic yield of percutaneous needle aspiration and biopsy was 57.6%(19/33) of benign SPNs and 81.0%(47/58) of malignant SPNs. The diagnostic value of sputum analysis and bronchoscopic evaluations were relatively very low. (9) 42.3%(11/26) of SPNs of undetermined etiology preoperatively turned out to be malignant after surgical resection. Overall, 75.4%(46/61) of surgically resected SPNs were malignant. Conclusions : We conclude that the likelihood of malignant SPN correlates the age of patient, prior history of malignancy, some CT findings including lobulated or spiculated border, air-bronchogram, pleural tail and lymphadenopathy. However, the history of smoking, the size of the nodule, and the volume doubling time are not helpful to determent whether the SPN is benign or malignant, which have been regarded as valuable clinical parameters previously. We suggest that aggressive diagnostic approach including surgical resection is necessary in patient with SPNs.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.18 no.1
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• pp.10-15
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• 2007

Probably the three most important components to a comprehensive evaluation of patients with attention-deficit hyperactivity disorder (ADHD) are the clinical interview, the medical examination, and the completion and scoring or behavior rating scales. Teachers and other school personnel are often the first to recognize that a child or adolescent might have ADHD, and often play an important role in the help-seeking/referral process. A diagnostic evaluation for ADHD should include questions about ADHD symptoms, other problems including alcohol and drug use, family history of ADHD, prior evaluation and treatment for ADHD. Screening interview or rating scales as well as interviews should be used. When it is feasible, clinicians may wish to supplement these components of the evaluation with objective assessments of the ADHD symptoms, such as psychological tests. These tests are not essential to reaching a diagnosis, however, or to treatment planning, but they may yield further information about the presence and severity of cognitive impairments that could be associated with some cases of ADHD. Screening for intellectual ability and academic achievement skills is also important in determining the presence of comorbid developmental delay or loaming disabilities. The number and type of symptoms required for a diagnosis of ADHD vary depending on the specific subtype. To receive a diagnosis of ADHD, the person must be experiencing significant distress or impairment in daily functioning, and must not meet criteria for other mental disorders which might better account for the observed symptoms such as mental retardation, autism or other pervasive developmental disorders, mood disorders, anxiety disorders. This report aims to suggest a practice guideline of assessment and diagnosis for children and adolescents with ADHD in Korea.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.28 no.2
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• pp.58-69
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• 2017

Attention-deficit hyperactivity disorder (ADHD) is a highly prevalent, impairing, and comorbid disorder that persists into adulthood. ADHD should be diagnosed in the same manner as other common adult mental health disorders. The three most important components in the comprehensive evaluation of patients with ADHD are the clinical interview, medical examination, and completion and scoring of behavior rating scales. The diagnostic evaluation of ADHD should include questions about the symptoms, family history, prior evaluation and treatment of ADHD, as well as other problems including alcohol and drug use. Screening interviews or rating scales, as well as interviews, should be used. When it is feasible, clinicians may wish to supplement these components of the evaluation with the objective assessments of the ADHD symptoms, such as through psychological tests. These tests are not essential to reaching a diagnosis, however, or to treatment planning, but may yield further information about the presence and severity of cognitive impairments that could be associated with some cases of ADHD. As comorbidity is the rule rather than the exception, clinicians should carefully screen for comorbid disorders as part of a comprehensive assessment of ADHD. To receive a diagnosis of ADHD, the person must be experiencing significant distress or impairment in his or her daily functioning, and must not meet the criteria for other mental disorders which might better account for the observed symptoms, such as mental retardation, autism or other pervasive developmental disorders, mood disorders and anxiety disorders. This report aims to suggest practice guidelines for the assessment and diagnosis of children, adolescents and adults with ADHD in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.479-483
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• 2003

Knowledge of N accumulation during the vegetative growth stage of rice (Oryza sativa L.) is useful for determining the need for topdressing fertilizer N at panicle initiation and booting stage. The chlorophyll content showing SPAD threshold values generated by a simple and portable diagnostic instrument, chlorophyll meter, enables implement the measures of greenness and/or relative chlorophyll contents of leaves. Two-year field experiment was conducted to evaluate the possible application of the chlorophyll meter for N diagnosis in transplanted paddy rice. The chlorophyll meter threshold values (SPAD reading) were taken from uppermost fully expanded leaves at 10days interval from 10 days after transplanting. SPAD readings and N contents of rice leaf blade were closely related at the maximum tillering stage. SPAD readings during growth period showed M-shaped distribution, sharply finished to drop at 20 days after heading date. As N fertilizer increased, the SPAD readings increased. The SPAD readings showed more critical and clear difference in immature paddy field than in ordinary paddy field, where the former soil showed higher response to N fertilizer topdressed. Based on the PAD readings for obtaining an optimum sink size bearing the maximum grain yield, N fertilizer to be dressed at the panicle initiation stage is to be adjusted within the SPA$\times$tillers value range 888 in ordinary paddy, and 800 in immature paddy vice. Among the cultivars tested, Huckhyangbyeo, Jinpumbyeo, Ansungbyeo, Sobibyeo, Manpungbyeo, Sangmibyeo, Jinbongbyeo, showed high SPAD values, whereas the cultivars, Nonghobyeo, Saechuchungbyeo, Hwabongbyeo, Mananbyeo, did low values and others intermediate SPAD threshhold values.

• The Journal of the Korean bone and joint tumor society
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• v.10 no.2
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• pp.113-119
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• 2004

Purpose: To determine the utility of sonographically guided percutaneous core needle biopsy to diagnose musculoskeletal soft tissue masses. Methods: A prospective study was performed in 55 patients referred for image-guided needle biopsy of primary or recurrent soft tissue masses and bone lesion or suspected solitary metastasis with extraosseous masses. Tissue samples were obtained with a 14-gauge or 18-gauge cutting needle coupled to an automated biopsy device under local anesthesia and sonographic guidance. Statistical analysis was based on 49 biopsies confirmed by successful clinical treatment (11 cases) or surgical resection (38 cases). Results: An accurate diagnosis was obtained in 47 (97%) of 49 biopsies; sensitivity was 95%, and specificity was 100%. The method did not yield sufficient tissue to establish a diagnosis in 6 cases. Considering all 55 biopsies, high-quality specimens were obtained in 87%. There were no serious complications. Conclusions: Sonographically guided core needle biopsy is accurate and safe, in soft tissue masses and bone tumors with extraosseous masses in the appendicular skeleton. In such patients, the sonographically guided procedure is the most prompt and effective method for obtaining tissue samples.

• The Journal of Internal Korean Medicine
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• v.29 no.2
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• pp.443-455
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• 2008

Objectives : This study was designed to research whether HRV can yield a suitable diagnosis for activity of autonomic nerve system on functional dyspepsia. Methods : The testing of HRV was carried out at the Oriental Medical Center of Dong-Eui University with the participation of 28 functional dyspepsia patients, 25 dyspepsia caused by organic disease patients and 33 control group people. We checked HRV of the three groups for 5 minutes and compared HRV index(frequency domain analysis: HF, LF, VLF, LF/HF Ratio, TP) between groups. Results were as follows : 1. In the frequency domain analysis, HF, LF, VLF, and TP were significantly lower than the control group in the functional dyspepsia patients and dyspepsia caused by organic disease groups. HF, LF, VLF, LF/HF ratio, and TP were not significantly different between functional dyspepsia group and dyspepsia caused by organic disease group. 2. Age in dyspepsia patient group was significantly higher than in the control group. 3. In the frequency domain analysis, LF, VLF, and TP were significantly lower in the functional dyspepsia group than the control group in age 20-30 years. HF, LF, VLF, LF/HF ratio, and TP were not significantly different between the control group and dyspepsia caused by organic disease group in ages 20-30 years. HF, LF, VLF, LF/HF ratio, and TP were not significantly different between functional dyspepsia group and dyspepsia caused by organic disease group in age 20-30 years. Conclusion : According to this study, autonomic nerve system and parasympathetic nerve system decreased more in the functional dyspepsia patient group compared with the control group.

• Tuberculosis and Respiratory Diseases
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• v.73 no.2
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• pp.107-114
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• 2012

Background: This study attempted to investigate the main causes of hemoptysis, the type of examinations used for diagnosis, the treatment modalities and outcomes. Methods: A retrospective study was conducted on the medical records of 221 patients admitted to the Chonnam National University Hospital, between January 2005 and February 2010, with hemoptysis. Results: Bronchiectasis (32.6%), active pulmonary tuberculosis (18.5%), fungus ball (10.8%), and lung cancer (5.9%) accounted for most causes of hemoptysis. Computed tomography scan was the most sensitive diagnostic test when employed alone, with positive yield of 93.2%. There were 161 cases of conservative treatment (72.9%), 42 cases of bronchial artery embolization (BAE) (19.0%), and 18 cases of surgery (8.1%). Regarding the amount of hemoptysis, 70 cases, out of 221 cases, were mild (31.5%), 36 cases moderate (16.2%), and 115 cases massive hemoptysis (52.0%). Most of the patients were treated conservatively, but if there was more bleeding present, BAE or surgery was more commonly performed than the conservative treatment ($p{\leq}0.0001$). In the multivariate model, severe hemoptysis and lung cancer were independently associated with short-term recurrence. BAE was independently associated with long-term recurrence, and lung cancer was associated with in-hospital mortality. The overall in-hospital mortality rate was 11.3%. Conclusion: Hemoptysis is a common symptom with a good prognosis in most cases. However, patients exhibiting massive bleeding or those with malignancy had a poorer prognosis. In-hospital mortality was strongly related to the cause, especially in lung cancer.