• Journal of Microbiology
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• v.33 no.3
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• pp.215-221
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• 1995

S. coelicolor A3(2) cells were treated with various redox-cycling agents on nutrient agar plates and examined for their effect on the growth and differentiation. When treated with plumbagin, severe effect on cell viability was observed at concentrations above 250 $\mu$M. However, the surviving colonies differentiated normally. When treated with 100 $\mu$M paraquat, growth rate was decreased and morphological differentiation was inhibited, while the survival rate was maintained at about 100% even at 5 mM paraquat. Menadione or lawsone did not cause any visible changes at concentrations up to 1 mM. The effect of paraquat was also observed when it was added to nutrient agar plate before spore inoculation. Paraquat had also observed when it was added to nutrient agar plate before spore inoculation. Paraquat had no effect on colonies growing on R2YE agar plates. Among the components of R2YE medium selectively added to nutrient agar medium, CaCl$_2$ was found to have some protective function from the inhibitory effect of paraquat. As a first step to study the mechanism of the inhibitory effect of paraquat on differentiation, resistant mutants which sporulate well in the presence of paraquat were screened following UV mutagenesis. Three paraquat-resistant mutants were isolated with a frequency of 3 $\times$10${-5}$. Their mutation sites were determined by genetic crossings. All three mutations were mapped to a single locus near arg4 at about 1 o'clock on the genetic map of S. coelicolor A3(2).

• Biomolecules & Therapeutics
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• v.30 no.3
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• pp.213-220
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• 2022

Although there have been advances in cancer therapy and surgical improvement, lung cancer has the lowest survival rate (19%) at all stages. This is because most patients are diagnosed with concurrent metastasis, which occurs due to numerous related reasons. Especially, lung cancer is one of the most common and malignant cancers in the world. Although there are advanced therapeutic strategies, lung cancer remains one of the main causes of cancer death. Recent work has proposed that epithelial-mesenchymal transition (EMT) is the main cause of metastasis in most cases of human cancers including lung cancer. EMT involves the conversion of epithelial cells, wherein the cells lose their epithelial abilities and become mesenchymal cells involved in embryonic development, such as gastrulation and neural crest formation. In addition, recent research has indicated that EMT contributes to altering the cancer cells into cancer stem cells (CSCs). Although EMT is important in the developmental stages, this process also activates lung cancer progression, including complicated and diverse signaling pathways. Despite the numerous investigations on signaling pathways involved in the progression of lung cancer, this malignancy is considered critical for treatment. EMT in lung cancer involves many transcription factors and inducers, for example, Snail, TWIST, and ZEB are the master regulators of EMT. EMT-related factors and signaling pathways are involved in the progression of lung cancer, proposing new approaches to lung cancer therapy. In the current review, we highlight the signaling pathways implicated in lung cancer and elucidate the correlation of these pathways, indicating new insights to treat lung cancer and other malignancies.

• Journal of Chest Surgery
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• v.56 no.1
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• pp.6-13
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• 2023

Background: Coronavirus disease 2019 (COVID-19) has been found to cause life-threatening respiratory failure, which can progress to irreversible lung damage. Lung transplantation can be a life-saving treatment in patients with terminal lung disease (e.g., acute respiratory distress syndrome caused by infection). This study aimed to present the clinical course and results after initial lung transplantation in patients with severe COVID-19 who did not recover even with optimal medical care. Methods: From August 2019 to February 2022, this study enrolled 10 patients with COVID-19 (5 men; median age, 55.7 years) who underwent lung transplantation at a single center in Korea. All patients' characteristics, clinical pathway, overall survival, complications, and operative data were collected and analyzed. Results: Veno-venous extracorporeal membrane oxygenation or an oxygenator in a right ventricular assist device circuit was applied to 90% of the patients, and the median length of extracorporeal life support before operation was 48.5 days. There were no cases of mortality after a median follow-up of 372.8 days (interquartile range, 262.25-489 days). The major complications included the requirement for postoperative extracorporeal membrane oxygenation support in 2 cases (20%), re-transplantation in 1 case (10%), and re-exploration due to bleeding in 2 cases (20%). During the follow-up period, 3 out of 10 patients died. Conclusion: Excellent early outcomes were observed for patients who underwent lung transplantation. Thus, lung transplantation can be an effective and feasible treatment for patients with end-stage lung disease caused by COVID-19.

• Tuberculosis and Respiratory Diseases
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• v.65 no.1
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• pp.15-22
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• 2008

Background: Lung cancer is the leading cause of cancer death in South Korea since the year 2000 and it is more common in elderly patients, with a peak incidence at around 70~80 years of age. However, these elderly patients receive treatment less often than do the younger patients because of organ dysfunction related to their age and their comorbidities, and they show poor tolerance to chemotherapy. The aims of this study were to analyze the clinical characteristics and treatment-related survival of elderly patients with lung cancer. Methods: In this retrospective study, we analyzed the clinical data of 706 lung cancer patients who were diagnosed at hospitals in Daegu and Gyeongsangbukdo from January 2005 to December 2005. We compared the clinical characteristics and outcomes of the patients who were aged 70 years and older (elderly patients) with those clinical characteristics and outcomes of the younger individuals. Results: The median age of the patients was 68 years (from 29 to 93) and the elderly patients were 38.7% (n=273) of all the study's patients. Squamous cell carcinoma was the most common type of lung cancer in both the elderly and younger patient groups. Elderly patients had more symptoms of dyspnea and chronic obstructive pulmonary disease (COPD) than the younger patients (p<0.001 and p<0.001, respectively). A good performance status (ECOG 0-1) was less common for the elderly patients (p<0.001). The median survival of the non-small cell lung cancer (NSCLC) patients was significantly higher in the younger patient group than in the elderly patient group (962 days vs 298 days, respectively, p=0.001). However, the median survival of the NSCLC patients who received any treatment showed no significant difference between the younger patient group and the elderly patient group (1,109 days vs 708 days, respectively, p=0.14). Conclusion: Our data showed that appropriate treatment for selected elderly patients improved the survival of patients with NSCLC. Therefore, elderly NSCLC patients with a good performance status should be encouraged to receive appropriate treatment.

• The Korean Journal of Emergency Medical Services
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• v.9 no.2
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• pp.111-128
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• 2005

Background: Cardiac arrest is one of the most critical diseases which can likely lead to severe cerebral disability or brain death when the cases can not recover their circulation within 10 minutes. Saving out-of-hospital cardiac arrest cases is a recent concern in Korea. Resuscitation has become an important multidisciplinary branch of medicine, demanding a spectrum of skills and attracting a plethora of specialities and organizations. The best survival can be achieved if all the following links have been optimized : rapid access, and early CPR, defibrillation and ACLS, Since the "Utstein Style" was advocated in 1991, many reports about out-of-hospital cardiac arrest have been published based on this guideline. These differences prevent valid inter-hospital and international comparisons. However, it is not known how effective resuscitation has become to the patients. In other words, there are no guidelines for reviewing, reporting, and conducting research on resuscitation in Korea. This dissertation aims to provide the basic data for a unified reporting guideline of resuscitation in Korea and evaluating the out-of-hospital factors associated with survival discharge of out-of-hospital cardiac arrest. Methods: As for this study, uses the collected data about Out-of-hospital cardiac arrests at 4 area, from January, 2005 to April. 2005. With a retrospective study, 174 cases were analyzed. The data was recorded based on the Out-of-Hospital Utstein Style. Results: Resuscitation was performed on 174 out-of-hospital cardiac arrest cases at the 4 area 14 patients(8.1%) recovered their spontaneous circulation. Overall, the ROSC of the out-of-hospital cardiac arrest patients was 8.1%, which was poorer than that of western countries. Gender distribution was 50 females(28.7%) and 124 males(71.3%), approximately twice as many males as females. ROSC of witnessed arrests was found out to be 97.7%. The ratio of the witnessed arrest groups showed higher results than that of unwitnessed arrest groups in the above-examined cases. Cardiac etiology consisted of cardiac(33.5%), non-cardiac(45.7%), trauma(20.1%), and unknown(6.0%). Cardiac was the best performance. Initial rhythm showed Ventricular Tachycardia/pulseless Ventricular Fibrillation in 8 patients(6.0%), asystole in 100(75.2%) and unknown in 25(18.8%). The results of the Ventricular Tachycardia/pulseless Ventricular Fibrillation showed higher results than the others cases, The proportion of the cardiogenic cause was 33.5%, which was only half of western countries. Ventricular Tachycardia/pulseless Ventricular Fibrillation is relatively rare. These differences were due to the prevalent pattern of Out-of-hospital cardiac arrest as well as prematurity of the EMSS. Bystander CPR was practiced on 13 patients(7.52%). ROSC was shown in 46.2% cases. CPR by EMT was carried out on 167 cases(96.5%). ACLS by EMf was rare. From collapse, 4 cases(2.6%) arrived to ED within 6 minutes. 13 (8.6%) within 10 minutes, and 49(32.5%) over 31 minutes. The sooner the patients arrived, the greater the ratio of ROSC and discharged alive became, and the same with collapse time to ROSC. As the results of the logistic regression analysis, ROSC was found out to be highly influenced by the time of ED arrival from collapse and Ventricular Tachycardia/pulseless Ventricular Fibrillation. Therefore, the ratio of ROSC depends on not any single factor but various intervention factors. Conclusion: This dissertation presents the following suggestions and directions of the study hereafter. First, the first step for a chain of survival should be taken to activate EMSS early with a phone as soon as cardiac arrests are witnessed. Second, it is keenly needed that emergency medical technicians should be increased through emergency education for living. Third, it is necessary to establish the emergency transportation system. Fourth, most of the Koreans have little understanding of EMT and the present operation systems have many problems, which should be fundamentally changed. Fifth, it is required to have an active medical control over Out-of-hospital CPR, And proper psychological supports should be given not only to patients themselves and their family but also individuals who are engaged in emergency situation. Finally, through studies hereafter on nationwide, comprehensive, and standard forms, it is needed to examine into the biological figures of human body, causes and trends of cardiac arrests, and then, to enhance the survival rate of Out-of-hospital cardiac arrests. Korean guidelines for Cardiopulmonary resuscitation need to be made.

• Radiation Oncology Journal
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• v.12 no.3
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• pp.377-386
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• 1994

Purpose: The role of radiotherapy in the management of patients with locoregional recurrent cervix cancer after radical surgery were retrospectively analyzed. Methods and materials: Twenty-eight patients treated with radiotherapy for locoregional recurrence after primary surgery for carcinoma of the cervix between 1989 and 1993 were analyzed. The median follow-up of survivors was 15 months (ranged 7-43 months). Eight patients had their disease confined to the vagina and 19 patients($68\%$) had pelvic mass as part of their locoregional recurrent disease. Within 24 months after the initial surgery, $82\%$ of recurrences manifested themselves. All patients had whole pelvic irradiation with or without intracavitary radiotherapy(ICR). Results: Complete response(CR) was achieved in 18 patients($54\%$). Five of eighteen patients($28\%$) with initial CR developed second locoregional recurrence. Response to radiotherapy correlated strongly with tumor volume, site of recurrence and total radiation dose. The overall 2 year survival rate was $43\%$ and the disease free survival was $31\%$. Survival rate was significantly influenced by the factors of interval from operation to recurrence, size and site of recurrent tumor, radiation dose, response of radiotherapy, lymph node status as initial presentation, The principal cause of death was lung metastasis($36\%$). Conclusion: Radiotherapy is an excellent modality for control of locoregional recurrent cervix cancer. To improve local control and survival rate, whole pelvic external radiotherapy in addition to ICR with more than 75.0Gy at the depth of 1.0cm from vaginal mucosa is needed and frequent follow up and early detection of recurrence is suggested as well.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.447-454
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• 1998

Purpose : This study evaluated the survival, local control, prognostic factor, and failure pattern of patients with esophageal cancer treated with operation and adjuvant radiation therapy to use as fundermental data of postoperative radiation therapy. Materials and Methods : A retrospective analysis was undertaken of 82 patients who had locally advanced esophageal cancer treated with operation and adjuvant radiation therapy from January 1988 to December 1995. According to AJCC staging, stage IIA were in 26 patients, stage IIB in 4 patients, and stage III in 52 patients. Squamous cell carcinoma were in 77 patients, adenosquamous carcinoma in 3 patients, and adenocarcinoma in 2 patients. The patients received radiation therapy ranging from 41.0 Gy to 64.8 Gy. Five patients received neoadjuvant chemotherapy. Results : Two-year survival and local control rates for all patients were 36.8$\%$ and 30.4$\%$ respectively. And they were 9.3$\%$ and 26.3$\%$ respectively at 5 years. According to stages, 2-year survival rates were 50.2$\%$ in IIA, 0$\%$ in IIB and 23.3$\%$ in III (p=0.004). Two-year local control rates were 49.2 $\%$ in IIA, 66.6$\%$ in IIB and 24.7$\%$ in III (p=0.01). Sixty patients developed recurrence, which were 3 tumor margin, 23 lymph node recurrence, 4 tumor margin and lymph node, 1 tumor margin and distant metastasis, 9 lymph node and distant metastasis, 17 distant metastasis and 3 unknown metastatic site. Prognostic factors affecting survival were smoking (p=0.02), T-staging (p=0.0092), N-staging (p=0.0045). Prognostic factors affecting local control were T-staging (p=0.019), N-staging (p=0.047). Conclusion : In spite of post-operative radiation therapy, predominant failure pattern was local failure. Especially regional lymph node failure was major cause of local failure. So strategy of aggresive adjuvant radiation therapy to regional lymph node area in post operative treatment should be proposed.

• Tuberculosis and Respiratory Diseases
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• v.59 no.1
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• pp.109-113
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• 2005

Miliary tuberculosis is the most serious form of tuberculous disease, but is rarely complicated with acute respiratory distress syndrome (ARDS). When a patient with miliary tuberculosis initially presents with ARDS, the mortality is much higher. Therefore, the early detection of miliary tuberculosis as the underlying cause of ARDS is very important for the prognosis and survival of the patient. The diagnosis of miliary tuberculosis may be easy if the patient presents typical clinical manifestations associated with the characteristic pattern of miliary nodules on chest radiology. However, the diagnosis of miliary tuberculosis when complicated with ARDS can be difficult due to the nonspecific radiologic patterns, such as diffuse bilateral consolidation and ground glass opacity, without miliary nodular infiltration. However, these nonspecific patterns are known as less likely findings of miliary tuberculosis. We experienced a pregnant woman with miliary tuberculosis, mimicking ARDS due to bilateral severe pneumonia. She was admitted, via the emergency room, with sudden onset of fever, chill, cough and dyspnea. The initial chest PA and HRCT showed diffuse bilateral consolidation and ground glass opacity, without miliary nodular infiltration. All bacteriological studies, including blood and sputum cultures, tuberculosis-PCR and serologic study for infectious disease were negative. However, the definite diagnosis of unusual miliary tuberculosis as the underlying cause of ARDS was confirmed from the radiological finding and transbronchial fiberoptic lung biopsy. We report this case, with a review of the literature.

• Radiation Oncology Journal
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• v.20 no.4
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• pp.323-327
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• 2002

Purpose : To evaluate the outcome of early stage non-small cell lung cancer patients who were treated with radiation therapy alone and define the optimal radiotherapeutic regimen for these patients. Materials and Methods : A retrospective review was peformed on patients with sage I or II non-small cell carcinoma of the lung that were treated at our institution between June, 1987 and May, 2000. A total of 21 patients treated definitively with radiation therapy alone were included in this study. The age of the patients ranged from 53 to 81 years with a median of 66 years. All the patients were male. The medical reasons for inoperability were lack of pulmonary reserve, cardiovascular disease, poor performance status, old age, and patient refusal in the decreasing order. Pathological evidence was not adequate to characterize the non-small cell subtype in two patients. Of the remaining 19 patients, 16 had squamous cell carcinoma and 3 had adenocarcinoma. Treatment was given with conventional fractionation, once a day, five times a week. The doses to the primary site ranged from 56 Gy to 59 Gy. No patients were lost to follow-up. Results : The overall survival rates for the entire group at 2, 3 and 5 years were 41, 30 and $21\%$, respectively. The cause specific survivals at 2, 3 and 5 years were 55, 36 and $25\%$, respectively. An intercurrent disease was the cause of death in two patients. The cumulative local failure rate at 5 years was $43\%$. Nine of the 21 patients had treatment failures after the curative radiotherapy was attempted. Local recurrences as the first site of failure were documented in 7 patients. Therefore, local failure alone represented $78\%$ of the total failures. Those patients whose tumor sizes were less than 4 cm had a significantly better 5 year disease free survival than those with tumors greater than 4 cm $(0\%\;vs\;36\%)$. Those patients with a Karnofsky performance status less than 70 did not differ significantly with respect to actuarial survival when compared to those with a status greater than 70 $(25\%\;vs\;26\%,\;p>0.05)$. Conclusion : Radiation therapy 리one is an effective and safe treatment for early stage non-small ceil lung cancer patients who are medically inoperable or refuse surgery. Also we believe that a higher radiation dose to the primary site could improve the local control rate, and ultimately the overall survival rate.

• Tuberculosis and Respiratory Diseases
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• v.59 no.3
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• pp.286-297
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• 2005

Background : Non-small cell lung cancer (NSCLC) is a common cause of cancer-related death in North America and Korea, with an overall 5-year survival rate of between 4 and 14%. The TNM staging system is the best prognostic index for operable NSCLC . However, epidermal growth factor receptor (EGFR), matrix metalloproteinase-9(MMP-9), and C-erbB-2 have all been implicated in the pathogenesis of NSCLC and might provide prognostic information. Methods : Immunohistochemical staining of 81 specimens from a resected primary non-small cell lung cancer was evaluated in order to determine the role of the biological markers on NSCLC . Immunohistochemical staining for EGFR, MMP-9, and C-erbB-2 was performed on paraffin-embedded tissue sections to observe the expression pattern according to the pathologic type and surgical staging. The correlations between the expression of each biological marker and the survival time was determined. Results : When positive immunohistochemical staining was defined as the extent area>20%(more than Grade 2), the positive rates for EGFR, MMP-9, and C-erbB-2 staining were 71.6%, 44.3%, and 24.1% of the 81 patients, respectively. The positive rates of EGFR and MMP-9 stain for NSCLC according to the surgical stages I, II, and IIIa were 75.0% and 41.7%, 66.7% and 47.6%, and 76.9% and 46.2%, respectively. The median survival time of the EGFR(-) group, 71.8 months, was significantly longer than that of the EGFR(+) group, 33.5 months.(p=0.018, Kaplan-Meier Method, log-rank test).. The MMP-9(+) group had a shorter median survival time than the MMP-9(-) group, 35.0 and 65.3 months, respectively (p=0.2). The co-expression of EGFR and MMP-9 was associated with a worse prognosis with a median survival time of 26.9 months, when compared with the 77 months for both negative-expression groups (p=0.0023). There were no significant differences between the C-erbB-2(+) and C-erbB-2 (-) groups. Conclusion : In NSCLC, the expression of EGFR might be a prognostic factor, and the co-expression of EGFR and MMP-9 was found to be associated with a poor prognosis. However, C-erbB-2 expression had no prognostic significance.