• Title, Summary, Keyword: Refractory

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Chemical Characteristics of PM1 using Aerosol Mass Spectrometer at Baengnyeong Island and Seoul Metropolitan Area (백령도 및 서울 대기오염집중측정소 에어로졸 질량 분석기 자료를 이용한 대기 중 에어로졸 화학적 특성 연구)

  • Park, Taehyun;Ban, Jihee;Kang, Seokwon;Ghim, Young Sung;Shin, Hye-Jung;Park, Jong Sung;Park, Seung Myung;Moon, Kwang Joo;Lim, Yong-Jae;Lee, Min-Do;Lee, Sang-Bo;Kim, Jeongsoo;Kim, Soon Tae;Bae, Chang Han;Lee, Yonghwan;Lee, Taehyoung
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.3
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    • pp.430-446
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    • 2018
  • To improve understanding of the sources and chemical properties of particulate pollutants on the Korean Peninsula, An Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) measured non-refractory fine particle ($NR-PM_1$) from 2013 to 2015 at Baengnyeong Island and Seoul metropolitan area (SMA), Korea. The chemical composition of $NR-PM_1$ in Baengnyeong island was dominated by organics and sulfate in the range of 36~38% for 3 years, and the organics were the dominant species in the range of 44~55% of $NR-PM_1$ in Seoul metropolitan area. The sulfate was found to be more than 85% of the anthropogenic origin in the both areas of Baengnyeong and SMA. Ratio of gas to particle partition of sulfate and nitrate were observed in both areas as more than 0.6 and 0.8, respectively, representing potential for formation of additional particulate sulfate and nitrate. The high-resolution spectra of organic aerosol (OA) were separated by three factors which were Primary OA(POA), Semi-Volatility Oxygenated Organic Aerosol (SV-OOA), and Low-Volatility OOA(LV-OOA) using positive matrix factorization (PMF) analysis. The fraction of oxygenated OA (SOA, ${\fallingdotseq}OOA$=SV-OOA+LV-OOA) was bigger than the fraction of POA in $NR-PM_1$. The POA fraction of OA in Seoul is higher than it of Baengnyeong Island, because Seoul has a relatively large number of primary pollutants, such as gasoline or diesel vehicle, factories, energy facilities. Potential source contribution function (PSCF) analysis revealed that transport from eastern China, an industrial area with high emissions, was associated with high particulate sulfate and organic concentrations at the Baengnyeong and SMA sites. PSCF also presents that the ship emissions on the Yellow Sea was associated with high particulate sulfate concentrations at the measurement sites.

Relationship between Gb3 Expression and Cytotoxicity of Shiga-like Toxin I (Shiga-like Toxin I의 세포독성과 수용체 Gb3 발현과의 관계)

  • Lim, Suk-Hwan;Kim, Gi-Young;Kim, Hyung-Chun;Kim, Young-Hee;Son, Yong-Hae;Oh, Yang-Hyo;Park, Yeong-Min
    • Clinical and Experimental Pediatrics
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    • v.46 no.2
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    • pp.143-153
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    • 2003
  • Purpose : Infection with Shiga-like toxin (SLT)-producing Escherichia coli, an emerging human pathogen found particularly in young children under 5 years of age, causes a spectrum of illnesses with high morbidity and mortality, ranging from diarrhea to hemorrhagic colitis and hemolytic uremic syndrome. Host mediators play an important role in the pathogenesis of SLT-I toxicity. The experiments described here were designed to investigate the effect of SLT-I on TNF-${\alpha}$ production and to understand the effect of TNF-${\alpha}$ on GB3 expression. We also further examine the relationship between the Gb3 level and the differential susceptibility of cells to the cytotoxic action of SLT-I. Methods : The effect of purified SLT-1 from E. coli O157 : H7 (ATCC 43890) on tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) production in Raw264.7 cells was investigated. Many mediators regulate endothelial cell membrane expression of the glycolipid globotriaosyleramide (Gb3), which serves as the toxin receptor, suggesting that the host response to the toxin or other bacterial products may contribute to pathogenesis by regulating target cell sensitivity to the toxins. Therefore, the relationships between Gb3 expression and cytotoxicity against SLT-I on three types of cells were evaluated. Results : Detectable levels of TNF-${\alpha}$ were produced as early as six hours after induction and continued to increase during 48 hours by SLT-I. It was also found that Vero cells and dendritic cells (DC2.4 cells) expressed high levels of Gb3, 83% and 68%, respectively, and that Raw264.7 cells had a low level of Gb3 (29%) and appeared refractory to cytotoxicity against SLT-I. Vero cells and DC2.4 cells expressing high levels of Gb3 were highly susceptible to SLT-I. Furthermore, macrophages showed a resistance to SLT-I cytotoxicity, despite the fact that Gb3 expression was enhanced. Conclusion : These results strongly suggest that the expression of Gb3 is necessary but not sufficient to confer sensitivity of macrophages to SLT-I and further underpin the important role of SLT-I and its Gb3 receptors in the pathogenesis of E. coli O157 infection.

Reoperations after Fontan Procedures (폰탄 술식 후에 시행한 재수술)

  • Lee, Cheul;Kim, Yong-Jin;Lee, Jeong-Ryul;Rho, Joon-Ryang
    • The Korean Journal of Thoracic and Cardiovascular Surgery
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    • v.36 no.7
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    • pp.457-462
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    • 2003
  • Background: Surgical results of the Fontan procedures in patients with a single ventricle have improved. As the perioperative mortality continues to decline and late outcome is forthcoming, attention is now being directed toward late complications of the Fontan procedures. We retrospectively analyzed our experience with reoperations after Fontan procedures. Material and Method: Between January 1988 and December 2002, 24 patients underwent reoperations after Fontan procedures. The median age at Fontan procedures and reoperation was 3.3 years and 9.2 years, respectively. Types of initial Fontan procedures were atriopulmonary connection (n=11), lateral tunnel Fontan (n=11), and extracardiac conduit Fontan (n=2). Indications for reoperation included atrioventricular valve regurgitation (n=7), atrial arrhythmia (n=8), Fontan pathway stenosis (n=7), residual right-to-left shunt (n=5), etc. Result: Procedures performed at reoperation included atrioventricular valve replacement (n=6), conversion to lateral tunnel Fontan (n=5), conversion to extracardiac conduit Fontan (n=3), cryoablation of arrhythmia circuit (n=7), etc. There was no operative mortality. There were 2 late deaths. Mean follow-up duration was 2.7$\pm$2.1 years. All patients except two were in NYHA class I at the latest follow-up. Among 8 patients with preoperative atrial arrhythmia, postoperative conversion to normal sinus rhythm was achieved in 7 patients. Conclusion: Reoperations after Fontan procedures could be achieved with low mortality and morbidity. Reoperation may lead to clinical improvement in patients with specific target conditions such as atrioventricular valve regurgitation, refractory atrial arrhythmia, or Fontan pathway stenosis, especially in patients with previous atriopulmonary connection.

Oxidative Desulfurization of Marine Diesel Using Keggin Type Heteropoly Acid Catalysts (Keggin형 헤테로폴리산 촉매를 이용한 선박용 경유의 산화 탈황)

  • Oh, Hyeonwoo;Woo, Hee Chul
    • Clean Technology
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    • v.25 no.1
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    • pp.91-97
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    • 2019
  • Oxidative desulfurization (ODS) has received much attention in recent years because refractory sulfur compounds such as dibenzothiophenes can be oxidized selectively to their corresponding sulfoxides and sulfones, and these products can be removed by extraction and adsorption. In this work, The oxidative desulfurization of marine diesel fuel was performed in a batch reactor with hydrogen peroxide ($H_2O_2$) in the presence of various supported heteropoly acid catalysts. The catalysts were characterized by XRD, XRF, XPS and nitrogen adsorption isotherm techniques. Based on the sulfur removal efficiency of promising silica supported heteropoly acid catalysts, the ranking of catalytic activity was: $30\;H_3PW_{12}/SiO_2$ > $30\;H_3PMo_{12}/SiO_2$ > $30\;H_4SiW_{12}/SiO_2$, which appears to be related with their intrinsic acid strength. The $30\;H_3PW_{12}/SiO_2$ catalyst showed the highest initial sulfur removal efficiency of about 66% under reaction conditions of $30^{\circ}C$, $0.025g\;mL^{-1}$ (cat./oil), 1 h reaction time. However, through the recycle test of the $H_3PW_{12}/SiO_2$ catalyst, significant deactivation was observed, which was attributed to the elution of the active component $H_3PW_{12}$. By introducing cesium cation ($Cs^+$) into the $H_3PW_{12}/SiO_2$ catalyst, the stability of the catalyst was improved with changing the solubility, and the $Cs^+$ ion exchanged catalyst could be recycled for at least five times without severe elution.

Clinical Study of Topotecan as Second-Line Treatment in Small Cell Lung Cancer (소세포폐암의 2차요법으로서의 Topotecan의 치료효과)

  • Kim, Hak-Ryul;Yang, Sei-Hoon;Jeong, Eun-Taik
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.3
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    • pp.230-240
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    • 2002
  • Background : The majority of chemotherapy-treated small cell lung cancers(SCLC) patients eventually recur. Although many patients are in excellent physical condition at the time of recurrence, few drugs or drug combinations are capable of effecting a tumor regression in this setting. Topotecan, a topoisomerase I inhibitor, is one of the more widely studied single afents in SCLC. The aim of this study was to determine the response rate, survival and toxicity of topotecan as a second line traeatment SCLC. Materials and Methods : 19 patients with measurable SCLC, progressive during the first line chemotherapy (9 cases) or recurrent after the first line chemotherpy(10 cases), were enrolled in this study. Topotecan was administered as a 30-minute daily infusion at a dose of 1.5mg/$m^2$ for 5 consecutive days, every 3 weeks. Results : The overall response rate was 26.3%(5/19, CR 2, PR 3, SD 3, PD 11). The median survival was 24 weeks. The response rate and survival were poor in the nonresponders during first chemotherapy, those who were refractory to the first chemotherapy(recurrent within 3 months after completion of first chemotherapy) and extensive disease, but the results were not statistically significant. The toxicities were mainly hematologic and anemia grade III 1/90, leukopenia grade III 6/90 IV 4/90, thrombocytopenia grade III 1/90 IV 1/90, vomiting grade III 1/90 of cycles were occurred. There was no treatment-related deaths due to severe myelosuppression. Conclusion : Topotecan can be an active second line chemotherapeutic agent for treating SCLC.

Percutaneous Catheter Drainage of Lung Abscess (폐농양의 경피적 카테타 배농법)

  • Kim, Chang-Ho;Cha, Seoung-Ick;Han, Chun-Duk;Kim, Yeon-Jae;Lee, Yeung-Suk;Park, Jae-Yong;Jung, Tae-Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.2
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    • pp.158-164
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    • 1993
  • Background: Recently, lung abscess tends to be increased in patients with underlying disease, most of whom are unsuitable for surgery when medical treatment fails. The patients with giant lung abscesses do not frequently respond to antibiotics and often have life-threatening complications. Therefore, more intensive cares are required in these patients. We studied the results and effects of percutaneous catheter drainage in these patients. Method: We performed fluoroscopy-guided percutaneous pigtail catheter (8.3 F) drainage by Seldinger technique in 9 cases of lung abscess (in 7 cases, intractable to medical treatment for an average of 8.4 days and in 2 cases, catheter drainage immediately performed due to a large cavity that was initially 10 cm in diameter). We compared 10 cases of lung abscess as control group which had receieved conventional medical treatment alone. Results: Seven of the 9 patients in study group of percutaneous drainage and 7 of the 10 patients in control group of medical treatment alone clinically improved in the average of 1.8 and 8.7 days, respectively. The mean duration of drainage was 13.2 days. There were 3 cases of death from massive hemoptysis, asphyxia of pus, and sepsis in control group, as compared with 2 cases of death from hepatic encephalopathy and sepsis in study group. The malfunctions of catheter occurred in these 2 cases, obstruction and dislodgement. But there were no significant pleuropulmonary complications of percutaneous drainage. Conclusion: Percutaneous drainage is effective and relatively safe in the management of lung abscesses refractory to medical therapy or giant lung abscesses.

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The effect of Percutaneous pig-tail catheter drainage in the management of lung abscess and empyema (폐 농양및 농흉 치료에서 Pig-tail 도관 배액술의 효과)

  • Kim, Yeon Sao;Kim, Seong Min;Kim, Jin Ho;Lee, Kyung Sang;Yang, Suck Chul;Yoon, Ho Joo;Shin, Dong Ho;Park, Sung Soo;Lee, Jung Hee;Choi, Yo Won;Jean, Seok Chol;Kim, Young Tae
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.4
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    • pp.571-578
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    • 1996
  • Background : Long abscess is an accumulation of pus within a destroyed portion of the lung. Antibiotic therapy and postural drainge has proven to be an effective method of treatment for the majority of patients with pyogenic lung abscess. When medical therapy fails, thoracotomy and pulmonary resection are the current therapies. empyema is pus in the pleural space, and this term is deserved for effusions on which the Gram stain of the pleural fluid is positive. Initially, such collection may be drained via chest tribe. Recently, in patients who are judged to be unsuitable for surgery are in poor condition, percutaneous drainage using pig-tail catheter has been performed. We report out experience with 10 cases of lung abscess and 23 cases of empyema who were treated by percutaneous pit-tail catheter drainage. Subjects and Methods : Our study included 10 patients with lung abscess and 23 patients with empyema who were treated by percutaneous pig-tail catheter drainage, from January, 1990, to May, 1996, at Hanyang University then a pig-tail catheter was inserted into the abscess or the site of empyema under fluoroscopic and ultrasonograpic guidance. Following aspiration, the catheter was sutured into the skin, and connected to the suction tip. Catheter drainage was discontinued when the abscess of empyema was resolved in radiologically and clinically. Results : There were 2 cases of lung abscess caused by Staphylococcus aureus and Klebsiella pneumoniae and 14 cases of empyema caused by M. tuberculosis. The others were unknown. The duration of drainage was 1-2 weeks in 7 cases of lung abscess and 14 cases of empyema. In the 29 of 33 patients, percutaneous drainage were carried out successfully 20 of the 29 Gases rapidly improved. Conclusion : Percutaneous drainge is effective and relatively saute for management of lung abscess or empyema refractory to medical therapy or poor candidates for surgical treatment.

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Postcardiotomy Ventricular Support with Biomedicus Pump (Biomedicus pump를 이용한 개심술후 심실보조)

  • Kim, Won-Gon;Lee, Chang-Ha;Kim, Ki-Bong;Ahn, Hyuk;Rho, Ryang-Joon
    • The Korean Journal of Thoracic and Cardiovascular Surgery
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    • v.29 no.11
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    • pp.1218-1222
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    • 1996
  • The reported incidence of postcardiotomy cardiogenic shock not responding to conventional therapy is still 0.1 to 0.8%. For this group of patients, more aggressive form of circulatory support must be employed. Centrifugal pumps are a ventricular assist device most commonly used on this purpose, due to low cost and easy availability. Currently, however, clinical experience of centrifugal pumps as a ventricular assist device is rarely reported in Korea. From January 1992 to January 1996, 2986 patients underwent cardiac operations on cardiopulmonary bypass at Seoul National University Hospital. Refractory postcardiotomy cardiac failure requring ventricular support with a Biomedicus centrifugal pump developed in ten of these patients. There were eight men and two women, ranged in age from nine years to 77 years with a mean of 50$\pm$20 years. The primary surgical procedures consisted of isolated coronary revascularization in four patients, combined coronary revascularization and aortic valve replacement in two, aortic dissection repair in two, pulmonary embolectomy in one, and heart transplantation in one. Of the ten patients, five had left ventricular assistance, one had right ventricular assistance, and four had biventricular assistance. Duration of ventricular assistance ranged from 24 to 175 hours, with a mean of 76$\pm$51 hours. Seven patients were weaned from ventricular assistance, and four of them discharged. The causes of death for nonsurvivors were progressive cardiac failure in two patients and multiorgan failure, intractable ventricular fibrillation, irreversible brain injury, and mechanical problem, respectively, in the other four. Survival was not predicted by time on cardiopulmonary bypass, aortic cross-clamp time, or duration of ventricular support. Major complications included bleeding(7), renal failure(6), infection(3) and neurologic complication(2). These results indicate that a centrifugal pump can provide reasonably satisfactory short-term circulatory support.

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Suspected Upper Gastrointestinal Bleeding by Interaction of Clozapine and Buspirone (상부위장관 출혈이 의심되는 클로자핀과 부스피론의 상호작용)

  • Sung, Yu-Mi;Kim, Soo-In;Yun, Kyu-Wol;Lim, Weon-Jeong
    • Korean Journal of Psychosomatic Medicine
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    • v.14 no.1
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    • pp.62-66
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    • 2006
  • Introduction: Unexpected serious and lethal drug interactions can be occurred by polypharmacy for treatment-resistant psychiatric disorders. We report a case who has suspected upper gastrointestinal bleeding after the combination of clozapine and buspirone. Case : A 69-year-old woman with DSM-IV schizophrenia who was admitted to our hospital had no previous medical problems. Findings on physical exam, laboratory values, EEG, and a magnetic reso-nance imaging scans were no abnormality, except for slightly low level of hemoglobin at admission. Because of aggravating anxiety symptom, a trial of buspirone was begun from 15mg, in addition to olanzapine 30mg. And then olanzapine was switched to clozapine due to her treatment-refractory his-tory and poor response on this admission. Moreover, At the admission 11 weeks later, after 4 weeks of starting buspirone and clozapine, she was placed on a regimen of clozapine 300mg and buspirone 60mg. At this point, she started to complaint nonspecific abdominal pain for 4 days and then hematemesis, melena and hypotension were developed suddenly with negative findings in gastroduodenoscopy. After stopping all medication, the suspected upper gastrointestinal bleeding was subsided. After the regimen was switched back to clozapine only, psychotic symptoms were improved without the recurrence of the adverse events. Conclusion : We concluded that the upper gastrointestinal bleeding in this case was attributed to the drug interaction with clozapine and buspirone, although the definite mechanism is not clear. The clini-cians should be very cautious to prescribe the combination of clozapine and buspirone due to a possible lethal adverse effect.

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Clinical Efficacy of Belotecan (CKD-602), Newly Developed Camptothecin Analog, in the 2nd Line Treatment of Relapsed Small Cell Lung Cancer (재발된 소세포폐암환자에서 이차 약제로 사용되는 Belotecan (CKD-602)의 임상적 효용성)

  • Ban, Hee-Jung;Oh, In-Jae;Kim, Kyu-Sik;Ju, Jin-Yung;Kwon, Yong-Soo;Kim, Yu-Il;Lim, Sung-Chul;Kim, Young-Chul
    • Tuberculosis and Respiratory Diseases
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    • v.66 no.2
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    • pp.93-97
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    • 2009
  • Background: Belotecan (Camtobell, CKD-602, Chongkundang Pharm., Korea), a camptothecin derivative, has anticancer effects by inhibiting topoisomerase I such as topotecan. This study observed the response, survival and toxicity of belotecan monotherapy after the failure of etoposide and platinum (EP). Methods: Forty nine small cell lung cancer (SCLC) patients (M/F=41/8; age, 64.5${\pm}$7.6 (mean${\pm}$SD) years), who failed in their first line chemotherapy were enrolled in this study. Twenty one SCLC patients showed relapsed lung cancer more than 90 days after their priorEP chemotherapy (sensitive relapse group, SR) and 28 patients relapsed within 90 days (refractory relapse group, RR). Results: The response rate was 25%. Eleven patients showed partial responses and 5 patients could not be checked. The response rate of the SR and RR patients was similar. The relative dose intensity was lower in the responders (78${\pm}$15%) than non-responders (83${\pm}$13%, p=0.03). The median survival time (MST) was 10.3 months (290 days). The MST of the non-responders and responders was 186 days (95% CI; 67-305) and 401 days (95% CI; 234-568, p=0.07), respectively. The median progression free survival (MPFS) was similar in the SR (79 days) and RR (67 days) patients. Grade 3-4 neutropenia, anemia, and thrombocytopenia were observed in 59.6%, 12.8% and 23.4% of patients, respectively. Conclusion: The efficacy and survival were demonstrated in the second-line setting. However, a randomized comparative trial with topotecan will be needed.