• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.337-337
• /
• 2014

투명 전도성 산화물(transparent conductive oxide: TCO) 박막은 높은 투과율과 낮은 비저항 덕분에 LCD (liquid crystal display), PDP (plasma display panel), OLED (organic light emitting display) 등 평판 디스플레이에 널리 사용되고 있다. 현재 양산되고 있는 ITO (indium tin oxide)는 90% 이상의 높은 투과율과 우수한 전도성으로 인해 TCO 박막 가운데서 디스플레이 산업에서 가장 널리 쓰이고 있다. 그런데, ITO의 인듐산화물에 의한 간질성 폐렴(interstitial pneumonia)의 유발 위험이 있다든가, 인듐의 매장량이 적어 원자재 가격이 비싼 단점도 가지고 있다. 이에 최근 ITO를 대체할 수 있는 TCO물질로 많은 연구가 이루어지고 있는데, 특히 AZO (aluminum-doped zinc oxide)는 그 중 대표적인 대체물질로서 독성이 없고 가격도 저렴하여 많은 관심이 증폭되고 있다. 현재 AZO는 sol-gel 방법이나 CVD (chemical vapor deposition) 또는 스퍼터링 방법 등으로 증착되고 있다. 본 연구에서는 두 개의 이종타겟(hetero target)을 장착한 대향 타겟 스퍼터링(facing target sputtering: FTS) 장치를 사용하여 AZO 박막을 제작한다. 기존의 여러 증착법과 달리, FTS 장치는 두 타겟 사이에 형성되는 플라즈마 내의 ${\gamma}$-전자를 구속하게 되며, 낮은 가스 압력에서 고밀도 플라즈마가 생성되어 빠른 증착 속도와 안정적인 방전을 유지한 상태에서 박막을 증착할 수가 있다. 또한 기판과 플라즈마가 이격되어 있어 높은 에너지를 갖는 입자들의 기판 충돌을 억제할 수 있는 장점들을 갖는다. 이종 타겟인 ZnO와 Al2O3를 사용하고 각 타겟에 인가되는 파워 변화를 통해 AZO 박막 내 Al2O3의 성분비를 조절하였다. ZnO 타겟의 증착 파워를 100 W로 고정할 경우, Al2O3 타겟의 증착 파워가 (50~90) W으로 실험을 하였으며, Al2O3 타겟의 증착 파워가 70 W일 때 AZO 박막의 Al2O3 성분비는 2.02 wt.%이며 박막의 비저항 값은 $5{\times}10^{-4}{\Omega}{\cdot}cm$로 최소값을 보였다. 이러한 비저항의 변화는 파워에 따른 AZO 박막의 캐리어 이동도(Hall mobility)와 캐리어의 농도(Carrier Concentration)의 변화와 밀접한 관계가 있음을 보여주며, 특히 AZO 박막의 캐리어 농도와 캐리어 이동도는 AZO 박막을 형성하고 있는 결정립의 크기에 의존하는 것이 X-선 회절 패턴과 SEM으로부터 확인되었다. 특히, 본 연구에서는 두 개의 이종 타겟(hetero target) Al2O3와 ZnO를 장착하고 각각의 파워를 변화시켜 도핑 량을 조절할 수는 대향 타겟 스퍼터링(FTS: facing-target sputtering) 방법을 이용하여 제작된 AZO 박막에 대해 전기적, 광학적 및 구조적 특성을 분석하고 ITO의 대체물로서의 가능성을 검토하고자 한다.

• Childhood Kidney Diseases
• /
• v.1 no.2
• /
• pp.189-194
• /
• 1997

Oligomeganephronia is a rare congenital form of bilateral renal hypoplasia histologically characterized by reduction in number and hypertrophy of nephrons. Clinically, this condition is presented in early infancy with vomiting, polyuria, polydipsia and dehydration. The problems are readily corrected, but slowly progressive renal failure follows accompanied by failure to thrive, short stature, and renal osteodystrophy. We experienced three cases of oligomeganephronia. Case 1. : A 3 2/12 years old female child was incidentally diagnosed as renal failure at age of 2 months when she was hospitalized due to pneumonia. She had open renal biopsy and was diagnosed as bilateral dysplastic kidney. On OPD follow-up, she progressed to end-stage renal failure (BUN/Cr 114/4.6 mg/dl) and had renal transplantation. The specimen was shrunk remarkably and light microscopy showed oligomeganephronia. Case 2. : A 14 8/12 years old female child with proteinuria was detected in an annual urine screening program for school children, she was diagnosed as renal failure (BUN/Cr 33.9/4.1 mg/dl), and had $5{\times}4{\times}3\;cm$ sized mass on abdominal CT scan. She had renal biopsy, and the specimen showed oligomeganephronia. She had hemodialysis for six months, and renal transplantation along with bilateral nephrectomy was performed. Case 3. : A 14 8/12 years old male child was diagnosed having chronic nephritis and chronic renal failure at 3 years old, progressed to end-stage renal failure (BUN/Cr 87/9.6 mg/dl) on OPD follow-up, and had a rephrectomy and renal transplantation. The biopsy specimen showed oligomeganephronic hypoplasia, secondary focal segmental glomerolosclerosis, and chronic interstitial nephritis. We report 3 cases of oligomeganephronia that progressed to end-stage renal failure and had successful renal transplantation with a brief review of related literatures.

• Journal of Chest Surgery
• /
• v.26 no.6
• /
• pp.475-482
• /
• 1993

90 patients[75 men and 15 women] with the thoracic disease underwent video-assisted thoracic surgery[VATS] during the period March 1992 to February 1993. The thoracic diseases were classified into two groups of spontaneous pneumothorax and general thoracic patients and they were 66 and 24, respectively.The mean size of the tumor resected was 4.3 $\pm$ 2.0 cm x 3.3 $\pm$ 1.1 cm x 2.7 $\pm$ 1.0 cm. The mean time of anesthesia and operation were 90.0 $\pm$ 19.9 min and 43.7 $\pm$ 13.1 min in spontaneous pneumothorax group and 123.3 $\pm$ 40.3 min and 62.8 $\pm$ 32.2 min in general thoracic group. The mean period of postoperative chest tube drainage and hospital stay were 5.0$\pm$ 5.5 days and 6.6 $\pm$ 7.4 days in spontaneous pneumothorax group and 3.5$\pm$ 1.6 days and 9.5 $\pm$ 6.1 days in general thoracic group. The indications of VATS were 71 pleural disease[78.9%: 66 spontaneous pneumothorax; 3 pleural effusions ; 1 pleural paragonimus westermanii cyst; 1 malignant pleural tumor with metastasis to the lung], 9 mediastinal disease[10.0%: 5 benign neurogenic tumor; 2 pericardial cyst; 1 benign cystic teratoma; 1 undifferentiated carcinoma], 8 pulmonary parenchymal disease[8.9%: 3 infectious disease ; 3 interstitial disease ; 2 malignant tumor ], and 2 traumatic cases of exploration and removal of hematoma[2.2%]. The applicated objectives of VATS were diagnostic[ 7 ], therapeutic[ 67 ] and both[ 16 ] and the performed procedures were pleurodesis[ 66 ], wedge resection of lung[ 59 ], parietal pleurectomy[ 11 ], removal of benign tumor[ 9 ], excision and/or biopsy of tumor[ 4 ], pleural biopsy and aspiration of pleural fluid[ 3 ] and exploration of hemothorax and removal of hematoma in traumatic 2 patients. The complication rate was 24.2%[ 16/66 ] in the spontaneous pneumothorax group and 8.3%[ 2/24 ] in the general thoracic group and so overally 20.0%[ 18/90 ]. The mortality within postoperative 30 days was 2.2%[ 2/90 ], including 1 acute renal failure and 1 respiratory failure due to rapid progression of pneumonia. The conversion rate to open thoracotomy during VATS was 5.6%[ 5/90 ], including 2 immediate postoperative massive air leakage, 1 giant bullae, 1 malignant pleural tumor with metastasis to lung and 1 pulmonary malignancy. The successful cure rate of VATS was 75.8%[ 50/66 ] in the spontaneous pneumothorax group and 76.5%[ 13/17 ] in the general thoracic group and the successful diagnostic rate was 100%[ 7/7 ]. In conclusion, although prospective trials should be progressed to define the precise role of VATS, the VATS carries a low morbidity and mortality and high diagnostic and therapeutic success rate and now can be effectively applicated to the surgical treatment of the extensive thoracic disease.

• Tuberculosis and Respiratory Diseases
• /
• v.43 no.4
• /
• pp.613-622
• /
• 1996

Constrictive bronchiolitis, one of small airway diseases, is very rare and occupies one of the two arms of bronchiolitis obliterans together with proliferative bronchiolitis. Proliferative bronchiolitis, presenting the prototype with bronchiolitis obliterans with organizing pneumonia(BOOP), can be easily taken into diagnostic consideration in terms of relatively rapid clinical course and radiologic presentation as if atypical pneumonia with interstitial and alveolar infiltrations. Meanwhile constrictive bronchiolitis is not only very Tare but also easily overlooked as chronic obstructive pulmonary diseases such as emphysema, because it usually shows normal chest radiographic finding and obstructive pattern in pulmonary function test. In the aspects of the response to treatment, proliferative bronchiolitis showed dramatic response to the corticosteroid while constrictive bronchiolitis is intractable, which is easily explained on the basis of the pathologic characteristics of cicartrical replacement of bronchiolar walls. The bronchiolitis, both proliferative and constrictive, can be associated with diverse conditions such as inhalational injury, postinfectious process, drug of chemical induced reactions, connective tissue diseases, and organ trasplantation. And there is idiopathic type which has no associated condition. There is one explanation that both types of bronchiolitis lie on the same disease spectrum because the different disease pattern can be evoked from the same etiology. In contrast, another explanation is suggested that both types of bronchiolitis are one of nonspecific tissue reaction rather than a disease specific histologic finding because the various types of causes can provoke the same histologic findings. These dilemma remains for further investigation. With literature investigation, the authors report a case of constrictive bronchiolitis proven by open lung biopsy in 47 year old female who was diagnosed as non-Hodgkin's lymphoma and simultaneously had relatively rapid progression of airflow obstruction and showed negative radiographic finding without the rise factors for the development of chronic obstructive lung disease. We consider it as idiopathic because we could not find any relationship between constrictive bronchiolitis and non-Hodgkin's lymphoma on the literature search and it requires further investigation.

• Tuberculosis and Respiratory Diseases
• /
• v.56 no.6
• /
• pp.611-618
• /
• 2004

Background : Idiopathic pulmonary fibrosis(IPF), a subtype of IIP(idiopathic interstitial pneumonia), is a fatal disease with a 3-5 year median survival. Many attempts at treating this condition have failed to demonstrate a survival benefit in IPF. Recently Ziesche et $al^{12}$ reported the efficacy of IFN-${\gamma}$ for treating IPF but there is still some controversy. The aim of this study was to determine the efficacy of IFN-${\gamma}$ in patients with advanced IPF who had not been responsive to steroid and cytotoxic agents. Method : Nine patients with advanced IPF(age: $55.4{\pm}15.3$ years, Male: Female=8:1) were enrolled. One year treatment regime with 2 million IU of IFN-${\gamma}$ administered subcutaneously three times a week, and low dose prednisolone(10-30 mg/d) was also used. In the case of a definite aggravation and serious side effects, the IFN-${\gamma}$ was discontinued. During the IFN-${\gamma}$ trial, a pulmonary function test and chest radiography were checked every three month throughout the study. Result : 1) Among 9 patients, only 4 patients were able to complete the 12 month treatment with IFN-${\gamma}$, and 5 patients died during the treatment period. 2) No improvement either in the respiratory symptoms or pulmonary functions were observed any of the patients, even in those who completed the 12 months trial of IFN-${\gamma}$, 3) At the time of IFN-${\gamma}$ trial, the survivors who finished the IFN-${\gamma}$ treatment for 12 months had a higher oxygen level($81.3{\pm}2.8$ vs. $67.4{\pm}8.4$, P=0.024) and a better pulmonary function(FVC: $61.3{\pm}5.1$ % predicted vs. $45.7{\pm}12.3%$, P=0.048, and $D_Lco$: $45.0{\pm}5.0%$ predicted vs. $30.8{\pm}11.2%$, P=0.048) than the non-survivors. Conclusion : Our data suggested that IFN-${\gamma}$ therapy was not effective in the patients with advanced IPF refractory compared with other therapeutic agents. Furthermore, these results suggest that severe impairment of the pulmonary function and hypoxemia during the IFN-${\gamma}$ therapy requires special attention.

• Tuberculosis and Respiratory Diseases
• /
• v.56 no.6
• /
• pp.619-627
• /
• 2004

Background : Corticosteroids in combination with cytotoxic drugs are the mainstays of therapy for idiopathic pulmonary fibrosis (IPF). However, there has been no regimen showing any survival benefit. The aim of this study was to describe a short-term clinical experience on interferon gamma-1b (IFN-${\gamma}1b$) therapy for IPF, as an antifibrotic agent. Methods : Medical records of 27 patients who were treated with IFN-${\gamma}1b$ (2 million IU, 3 times a week, subcutaneous injection) were retrospectively reviewed. Treatment response was assessed using ATS/ERS criteria in 17 patients who received IFN-${\gamma}1b$ for more than 6 months. In addition, we compared the efficacy of IFN-${\gamma}1b$ therapy with that of cyclophosphamide${\pm}$prednisolone therapy (n=26). Results : The median age of IFN-${\gamma}$ treated group (M:F=19:8) was 59 years (44-74 years). Compared to the patients who showed a stable response at 6 months (n=12), the deteriorated group (n=5) had worse baseline lung function (FVC, $55.4{\pm}11.3%$ vs. $70.7{\pm}10.9%$, p=0.019; DLco, $50.3{\pm}7.3%$ vs. $76.9{\pm}19.6%$, p=0.014). Lower baseline $PaO_2$ on room air breathing was observed in the deteriorated group ($68.6{\pm}7.8mmHg$ vs. $91.4{\pm}6.6mmHg$ p=0.001). Subcutaneous IFN-${\gamma}1b$ did not show better efficacy than prednisolone. Five patients discontinued IFN-${\gamma}$ because of severe side effects. ARDS developed in one patient, who eventually died. Conclusion : The administration of IFN-${\gamma}1b$ is not desirable for patients diagnosed with IPF with poor lung function. Long-term and large-scaled clinical studies are needed for its efficacy in IPF.

• Tuberculosis and Respiratory Diseases
• /
• v.59 no.1
• /
• pp.77-85
• /
• 2005

Background : According to the 2002 consensus report of the American Thoracic Society/European Respiratory Society (ATS/ERS), idiopathic pulmonary fibrosis (IPF) was classified as biopsy proven or probable IPF. Probable IPF is defined as those with distinctive features that allow for a confident diagnosis of IPF/usual interstitial pneumonia (UIP) within an appropriate clinical setting. The determination of the clinical course of probable IPF, as diagnosed by the ATS/ERS criteria, was studied. Methods : Between March 1995 and August 2002, 36 patients with probable IPF, from two tertiary referral hospitals, were enrolled in this study. The clinical characteristics, prognostic factors and treatment efficacy of these patients were retrospectively evaluated. Results : The mean age of the subjects was $65{\pm}6$ years. The one and 3 year survival rates were 82.4 and 50.3%, respectively, and a median survival period of 42.0 months. The total cell count of bronchoalveolar lavage was higher in the death than the survival group (p<0.05). No survival benefits were found in the cytoxan and steroid treatment groups compared with other treatment groups. Conclusion : These results suggest that the clinical course of probable IPF may be similar to that of biopsy-proven UIP. However, atypical patients must undergo an open lung biopsy for confirmation of the diagnosis.

• Tuberculosis and Respiratory Diseases
• /
• v.55 no.5
• /
• pp.478-487
• /
• 2003

Background : There have been several studies showing that the angiotensin II and angiotensin converting enzyme(ACE) contributes to the apoptosis of alveolar epithelial cells in idiopathic interstitial pneumonia and the activation of fibroblasts during the process of pulmonary fibrosis. These results suggest that the pulmonary fibrosis can be inhibited by the angiotensin II receptor antagonist(AGIIRA). This study was performed to identify the therapeutic effect of AGIIRA in idiopathic pulmonary fibrosis(IPF). Method : Thirteen patients with IPF, who were diagnosed with an open lung biopsy(6 patients) and furfilling the ATS criteria(7 patients) between March 1999 and October 2001 at the Gachon medical center, were enrolled in this study. Of these patients, eight patients were treated with a regimen including AGIIRA(AT group), and five were treated without AGIIRA(NT group). The pulmonary function tests and dyspnea(ATS scale) were measured at diagnosis and 1 year after treatment. All the data was collected to analyze the therapeutic effect of AGIIRA on the patients with IPF. Results : The AT group contained 8 patients(M:F=4:4) and the NT group contained 5 patients(M:F=3:2). There was no significant difference in the serum angiotensin II level between the two groups($202.5{\pm}58.5$ vs $163.7{\pm}47.3pg/ml$, p>0.05). The AT group showed an upward trend in TLC(+3%), FVC(+4%), FEV1(+3%) and DLco(+2%) compared to the NT group(TLC(-14%), FVC(-3%), FEV1(-4%) except for DLco(+5%)). The dyspnea score in the AT group improved significantly but not in the NT group. Conclusion : These results suggest that the angiotensin II receptor antagonist may have an effect on stabilizing IPF.

• Tuberculosis and Respiratory Diseases
• /
• v.65 no.4
• /
• pp.292-300
• /
• 2008

Background: Respiratory failure is a common condition that requires intensive care, and has a high mortality rate despite the recent improvements in respiratory care. Previous reports of patients with respiratory failure focused on the specific disease or included a large proportion of surgical patients. This study evaluated the clinical characteristics, outcomes and prognostic factors of adult patients receiving mechanical ventilation in a medical intensive care unit. Methods: Retrospective chart review was performed on 479 adult patients, who received mechanical ventilation for more than 48 hours in the medical ICU of one tertiary referral hospital. Results: The mean age of the patients was $60.3{\pm}15.6$ years and 34.0% were female. The initial mean APACHE III score was $72.3{\pm}25$. The cause of MV included acute respiratory failure (71.8%), acute exacerbation of chronic pulmonary disease (20.9%), coma (5.6%), and neuromuscular disorders (1.7%). Pressure controlled ventilation was used as the initial ventilator mode in 67.8% of patients, and pressure support ventilation was used as the initial weaning mode in 83.6% of the patients. The overall mortality rate in the ICU and hospital was 49.3% and 55.4%, respectively. The main cause of death in hospital was septic shock (32.5%), respiratory failure (11.7%), and multiorgan failure (10.2%). Males, an APACHE III score >70, the cause of respiratory failure (interstitial lung disease, coma, aspiration, pneumonia, sepsis and hemoptysis), the total ventilation time, and length of stay in hospital were independently associated with mortality. Conclusion: The cause of respiratory failure, severity of the patients, and gender appears to be significantly associated with the outcome of mechanical ventilatory support in patients with respiratory failure.

• Tuberculosis and Respiratory Diseases
• /
• v.61 no.5
• /
• pp.447-455
• /
• 2006

Background: MMPs and TIMPs are important factors for abnormal remodeling the pulmonary parenchyme in idiopathic interstitial pneumonia(IIP) This study evaluated the expression of MMPs and TIMPs in the tissue of IPF, NSIP and normal control subjects. Method: The MMP-2 and -9 activity in the lung tissue was studied by gelatin zymography, and the expression of MMP-1, -2, -9, TIMP-1 and -2 in the lung tissue was measured by immunohistochemistry. Thirty five patients, who were diagnosed with IIP (UIP ; 22, NSIP ; 13), were enrolled in the immunohistochemical study. Thirteen patients with IIP (UIP ; 9, NSIP ; 4) and five patients with lung cancer were enrolled in the zymographic assay. Results: (1) The immunohistochemistry for MMP-1,-2,-9, TIMP-1 and-2 ; MMP-1,-9 and TIMP-2 were stained stronger in the UIP subjects than NSIP and the normal control. TIMP-2 was strongly stained in the UIP tissue. particularly the fibroblasts in the fibroblastic foci. (2) Zymography for MMP-2 and MMP-9 revealed MMP-2 to have prominent expression in the UIP tissue than in the NSIP tissue. Conclusions: These results suggest that the overexpression of the TIMPs and gelatinases in UIP might be important factors in the irreversible fibrosis of the lung parenchyme.