• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.564-573
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• 1999

Background: With variable symptoms and nonspecific radiographic appearances, pulmonary embolism (PE) is a frequent and often undiagnosed cause of mortality and morbidity. The Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study suggested that the majority of patients undergoing ventilation-perfusion (V-Q) scan would require additional studies to establish or to exclude the diagnosis of PE. Pulmonary angiography has been regarded as gold standard for diagnosis of PE. However, it is an invasive procedure that may be associated with significant notable morbidity and mortality. Thus, availability of an accurate, noninvasive screening examination is highly desirable. Method: From October 1994 to February 1997, twenty patients (male 13, female 7, range 23-91 years, median 58 years) who were suspected as pulmonary embolism on the basis of clinical evidence and underwent the spiral volumetric computed tomography (spiral CT), were studied retrospectively to evaluate the effectiveness of spiral CT as a diagnostic tool in PE. Results: PE could be excluded with spiral CT in 4 patients ; diagnoses of these patients were lung cancer, pneumonia with lung abscess, bilateral pleural effusion due to congestive heart failure, nonspecific pulmonary abnormality retrospectively. One patient who disclosed high probability in V/Q scan, could be diagnosed as pneumonia with lung abscess and underlying emphysema with spiral CT. Among 4 patients who showed intermediate and low probability in V/Q scan, 3 patients could be confirmed as PE with spiral CT. Spiral CT was helpful in 3 patients, in whom V/Q scan could not be performed due to other reasons (e.g. night time, mechanical ventilation) to confirm the diagnosis of PE. Spiral CT could demonstrate embolus above lobar artery level in 11 patients, and up to segmental artery level in 5 patients. Conclusion: This study demonstrated that spiral CT could allow accurate demonstration of thrombotic clots in centrally localized embolism. Spiral CT could be effective, specific, noninvasive and useful diagnostic screening modality for the diagnosis of pulmonary embolism.

• Tuberculosis and Respiratory Diseases
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• v.69 no.2
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• pp.95-102
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• 2010

Background: The increasing rate of drug-resistant tuberculosis (TB) is a threat to the public health and TB control. In Korea, about 75~80% of TB patients are treated in private hospitals and the rate has been continuously increasing since 2000. Methods: On a retrospective basis, we enrolled 170 newly diagnosed with or retreated for multidrug-resistant TB (MDR-TB) in 2004 from 21 private hospitals. We extracted the following demographics and treatment history from patient medical records: initial treatment outcomes, cumulative survival rates, treatment outcomes, and prognostic factors. Results: Of the 170 patients, the majority were male (64.1%), the mean age was 44.5 years old, and mean body-mass-index was $20.2kg/m^2$. None of the patients tested positive for HIV. Eleven (6.5%) were confirmed to have extensively drug-resistant TB (XDR-TB) at treatment initiation. Treatment success rates were not different between XDR-TB (36.4%, 4/11) and non-XDR MDR-TB (51.6%, 82/159). Default rate was high, 21.8% (37/170). Far advanced disease on X-ray was a significant negative predictor of treatment success; advanced disease and low BMI were risk factors for all-cause mortality. Conclusion: In private hospitals in Korea, the proportion of XDR-TB in MDR-TB was comparable to previous data. The treatment success rate of MDR-/XDR-TB remains poor and the failure rate was quite high. Adequate TB control policies should be strengthened to prevent the further development and spread of MDR-/XDR-TB in Korea.

• Clinical and Experimental Pediatrics
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• v.45 no.8
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• pp.1000-1006
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• 2002

Purpose : In the course of treatment, patients with hematological or oncological disorders often develop pulmonary complication. The patients who develop a severe pulmonary complication have a poor outlook. The causes of pulmonary complication are either infectious or non-infectious in origin. We have analyzed the etiology and outcome of these patients admitted to the pediatric intensive care unit of Asan Medical Center. Methods : Medical records of 95 patients on Pediatric oncology service who were admitted to pediatric intensive care unit(PICU) of Asan Medical Center from Jan 1997 to May 2000 were retrospectively reviewed. Results : The mean age of the patients was 8.5 years(2 months-18 years). The underlying malignancies of these 95 patients were as following; acute lymphoblastic leukemia(31 cases), lymphoma (11 cases), acute myeloid leukemia(nine cases), brain tumor(eight cases) and other solid tumors(25 cases). Pulmonary complications included pneumonia, acute respiratory failure, pneumothorax and pleural effusion. The most common cause of pulmonary complication was infection(88%) in etiology. The overall mortality rate was 56.8%. Pulmonary complications in these patients carried high rates of mortality regardless of whether they were immune compromised(76%) or not(69%). Even without pulmonary complications, the hematological or oncological patients admitted to PICU had high mortality rates of 43%. Conclusion : Pulmonary complications are frequent finding in the hematological or oncological patients admitted to Intensive Care Unit. The main etiology of these pulmonary complications was infection, which carried a high mortality rate regardless of their immune status at the time when they were admitted to PICU.

• Journal of Veterinary Clinics
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• v.26 no.2
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• pp.138-143
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• 2009

Ischemia/reperfusion injury(I/RI) is the major cause of acute renal failure and delayed graft function(DGF) unavoidable in renal transplantation. Enormous studies on ischemia damage playing a role in activating graft rejection factors, such as T cells or macrophages, are being reported. Present study was performed to determine whether ischemia time would play an important role in activating rejection-related factors or not in rat models of I/RI. Male Sprague-Dawley rats were submitted to 30, 45, and 60 minutes of warm renal ischemia with nephrectomy or control animals underwent sham operation(unilateral nephrectomy). Renal function and survival rates were evaluated on day 0, 1, 2, 3, 5 and 7. Immunofluorescence staining of dendritic cells(DCs), natural killer(NK) cells, macrophages, B cells, CD4+ and CD8+ T cells were measured on day 1 and 7 after renal I/RI. Survival rates dropped below 50% after day 3 in 45 minutes ischemia. Histologic analysis of ischemic kidneys revealed a significant loss of tubular architecture and infiltration of inflammatory cells. DCs, NK cells, macrophages, CD4+ and CD8+ T cells were infiltrated from a day after I/RI depending on ischemia time. Antigen presenting cells(DCs, NK cells or macrophages) and even T cells were infiltrated 24 hours post-I/RI, which is at the time of acute tubular necrosis. During the regeneration phase, not only these cells increased but B cells also appeared in more than 45 minutes ischemia. The numbers of the innate and the adaptive immune cells increased depending on ischemia as well as reperfusion time. These changes of infiltrating cells resulting from each I/RI model show that ischemic time plays a role in activating rejection related immune factors and have consequences on progression of renal disease in transplanted and native kidneys.

• Radiation Oncology Journal
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• v.28 no.2
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• pp.85-90
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• 2010

Purpose: To evaluate the rate of tumor response, local control, and treatment-related complications after hypofractionated radiotherapy for recurrent hepatocelluar carcinoma (HCC) less than 5 cm in size. Materials and Methods: Among the HCC patients who were treated by radiotherapy (RT) between 2006 and 2007 after the failure of previous treatment, a total of 12 patients were treated with hypofractionated RT. The criteria for hypofractionated RT was as follows: 1) HCC less than 5 cm, 2) HCC not adjacent to a critical organ, 3) HCC without portal vein tumor thrombosis, and 4) less than 15% of normal liver volume that irradiated 50% of the prescribed dose. Hypofractionated RT was performed with 50 Gy delivered in 10 fractions, at a rate of 5 fractions per week. The evaluation of tumor response was determined by CT scans performed at 3 months after the cessation of RT, followed by the evaluation of toxicity by Common Terminology Criteria for Adverse Events version 3.0. The median follow-up period after radiotherapy was 18 months. Results: A complete response (CR) was achieved in 5 of 12 lesions (41.7%) at CT performed at 3 months after the cessation, whereas the overall complete response was observed in 7 of 12 cases (58.3%). In-field local control rate was sustained in 83.3% of patients. All patients developed intra-hepatic metastases except for 2 patients. The overall survival rate was 90.0% at 1 year and 67.5% at 2 years, respectively. Three patients developed Grade 1 nausea during RT and 1 patient showed a progression of ascites after RT. There was no grade 3 or greater treatment-related toxicities. Conclusion: Hypofractionated RT for small-sized HCC as a salvage therapy showed a 58.3% CR rate and 83.3% of local control. Fifty Gy administered in 10 fractions of partial liver irradiation is considered as a tolerable dose that does not cause severe complications.

• Journal of Energy Engineering
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• v.28 no.2
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• pp.18-35
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• 2019

The Korea District Heating Corporation operates a gas engine generator with a capacity of $4500m^3 /day$ of biogas generated from the sewage treatment plant of the Nanji Water Recycling Center and 1,500 kW. However, the actual operation experience of the biogas power plant is insufficient, and due to lack of accumulated technology and know-how, frequent breakdown and stoppage of the gas engine causes a lot of economic loss. Therefore, it is necessary to prepare technical fundamental measures for stable operation of the power plant In this study, a series of process problems of the gas engine plant using the biogas generated in the sewage treatment plant of the Nanji Water Recovery Center were identified and the optimization of the actual operation was made by minimizing the problems in each step. In order to purify the gas, which is the main cause of the failure stop, the conditions for establishing the quality standard of the adsorption capacity of the activated carbon were established through the analysis of the components and the adsorption test for the active carbon being used at present. In addition, the system was applied to actual operation by applying standards for replacement cycle of activated carbon to minimize impurities, strengthening measurement period of hydrogen sulfide, localization of activated carbon, and strengthening and improving the operation standards of the plant. As a result, the operating performance of gas engine # 1 was increased by 530% and the operation of the second engine was increased by 250%. In addition, improvement of vent line equipment has reduced work process and increased normal operation time and operation rate. In terms of economic efficiency, it also showed a sales increase of KRW 77,000 / year. By applying the strengthening and improvement measures of operating standards, it is possible to reduce the stoppage of the biogas plant, increase the utilization rate, It is judged to be an operational plan.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.4
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• pp.253-260
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• 2004

Objectives: Klinefelter syndrome is the most common genetic cause of male infertility and presents with 47, XXY mainly or 46, XX/47, XXY mosaicism. It is characterized by hypogonadism and azoospermia due to testicular failure, however, sporadic cases of natural pregnancies have been reported. With the development of testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI), sperm can be retrieved successfully and ART is applied in these patients for pregnancy. It has been suggested that the risk of chromosome aneuploidy for both sex chromosome and autosome is increased in the sperms from 47, XXY germ cells. Considering the risk for chromosomal aneuploidy in the offspring, preimplantation genetic diagnosis (PGD) could be applied as a safe and more effective treatment option in Klinefelter syndrome. The aim of this study is to assess the outcome of PGD cycles by using FISH for sex chromosome and autosome in patients with Klinefelter syndrome. Materials and Methods: From Jan. 2001 to Dec. 2003, PGD was attempted in 8 cases of Klinefelter syndrome but TESE was failed to retrieve sperm in the 3 cases, therefore PGD was performed in 8 cycles of 5 cases (four 47, XXY and one 46, XY/47, XXY mosaicism). In one case, ejaculated sperm was used and in 4 cases, TESE sperm was used for ICSI. After fertilization, blastomere biopsy was performed in $6{\sim}7$ cell stage embryo and the chromosome aneuploidy was diagnosed by using FISH with CEP probes for chromosome X, Y and 17 or 18. Results: A total of 127 oocytes were retrieved and ICSI was performed in 113 mature oocytes. The fertilization rate was $65.3{\pm}6.0%$ (mean$\pm$SEM) and 76 embryos were obtained. Blastomere biopsy was performed in 61 developing embryos and FISH analysis was successful in 95.1% of the biopsied blastomeres (58/61). The rate of balanced embryos for chromosome X, Y and 17 or 18 was $39.7{\pm}6.9%$. The rate of aneuploidy for sex chromosome (X and Y) was $45.9{\pm}5.3%$ and $43.2{\pm}5.8%$ for chromosome 17 or 18, respectively. Embryo transfer was performed in all 8 cycles and mean number of transferred embryos was $2.5{\pm}0.5$. In 2 cases, clinical pregnancies were obtained and normal 46, XX and 46, XY karyotypes were confirmed by amniocentesis, respectively. Healthy male and female babies were delivered uneventfully at term. Conclusion: The patients with Klinefelter syndrome can benefit from ART with TESE and ICSI. Considering the risk of aneuploidy for both sex chromosome and autosome in the sperms and embryos of Klinefelter syndrome, PGD could be offered as safe and more effective treatment option.

• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.516-521
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• 2003

The Aspergillus species produces metabolic products that play a significant role in the destructive processes in the lung. We experienced a case of chronic necrotizing pulmonary aspergillosis caused by an Aspergillus niger infection, which contained numerous calcium oxalate crystals in the necrotic lung tissue. A 46-year-old man, who had a history of pulmonary tuberculosis, presented with high fever, intermittent hemoptysis and pulmonary infiltrations with a cavity indicated by the chest radiograph. Despite being treated with several antibiotics and anti-tuberculosis regimens, the high fever continued. The sputum cultures yielded A. niger repeatedly, and intravenous amphotericin B was then introduced. The pathological specimen obtained by a transbronchial lung biopsy revealed numerous calcium oxalate crystals in a background of acute inflammatory exudates with no identification of the organism. Intravenous amphotericin B was continued at a total dose of 1600 mg, and at that time he was afebrile, although the intermittent hemoptysis continued. On the $63^{rd}$ hospital day, a massive hemoptysis (about 800 mL) developed, which could not be controlled despite embolizing the left bronchial artery. He died of respiratory failure the next day. It is believed that the oxalic acid produced by A. niger was the main cause of the patient's pulmonary injury and the ensuing massive hemoptysis.

• Childhood Kidney Diseases
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• v.7 no.2
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• pp.181-188
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• 2003

Purpose : Vesicoureteral reflux(VUR) is known to be the main cause of childhood hypertension and renal failure. Knowing its familial occurrence, we determined the incidence of VUR and renal scar in asymptomatic siblings of Korean patients with primary VUR Methods : A total of 50 siblings from 37 index patients were included. Voiding cystourethro-graphy(VCUG) and renal scintigraphy using $^{99m}Tc-DMSA$ were peformed in these siblings from June, 1994 to May, 2001, Index patients were classified into two groups according to the presence of VUR in their siblings, and the clinical factors of the index patients such as age, sex, grade of reflux and renal cortical defect were compared between the groups. Results : Among the 50 siblings, VUR were found in 8(16%) and renal cortical defects were detected in 8(16%) siblings respectively. The incidence of renal cortical defects was 87.5%(7 out of 8) in the VUR(+) siblings. There was a case of VUR(-) cortical defect in one sibling, presumed as a scar from an old VUR. There was no relationship among age, sex, grade of reflux and renal cortical defect of the index patient to the presence of VUR in siblings. Conclusion : This study confirmed a significant incidence of VUR(16%) and renal cortical defects(16%) in the asymptomatic siblings of patients with primary VUR in Korea. It Is resonable to recommend screening studies to the siblings of patients with VUR for the early detection and prevention of probable reflux nephropathy. (J K orean Soc Pediatr Nephrol 2003;7:181-188)

• Journal of Korean Philosophical Society
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• v.137
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• pp.57-79
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• 2016

The purpose of this paper is to explain MacIntyre's critique of moral pluralism of modern society and reveal the limits of his critique of liberalism. It is a distinctive feature of the social and cultural order that we inhabit that disagreements over central moral issues are peculiarly unsettleable. Debates concerned with the value of human life such as those over abortion and euthanasia, or about distributive justice and property rights, or about war and peace degenerate into confrontations of assertion and counter-assertion because the protagonists of rival positions invoke incommensurable forms of moral assertion against each other. We usually call this situation 'modern moral pluralism' and concede as the natural outcome of the activities of human reason under free institution. But in After Virtue, MacIntyre vigorously criticizes modern moral pluralism. The main cause he took which brought about this state of affairs was the failure of 'the Enlightenment project'. According to MacIntyre, the Enlightenment project which has dominated philosophy for the past three hundred years promised a conception of rationality independent of historical and social context, and independent of any specific understanding of man's nature or purpose. But not only has that promise in fact been unfulfilled, the project is itself fundamentally flawed and the promise could never be fulfilled. In consequence, modern moral and political thought are in a state of disarray from which they can be rescued only if we revert to an Aristotelian paradigm, with its essential commitment, and construct an account of practical reason premised on that commitment. But one of the deepest difficulties with the argument of After Virtue is that the very extent of its critique of the modern world seems to cast doubt on the possibility of any realistic revival under the conditions of modernity of the Aristotelianism which MacIntyre advocates. Especially when we consider we are not only the characters found in our narratives but also we ourselves are the author of our own narratives. Moral pluralism is not seen as disaster but rather as the natural outcome of the activities of human reason under enduring free institutions.