Whole Blood Interferon-γ Release Assay Is Insufficient for the Diagnosis of Sputum Smear Negative Pulmonary Tuberculosis

PURPOSE: We investigated the value of an interferon-γ release assay (IGRA) for the diagnosis of active pulmonary tuberculosis (PTB) among sputum smear negative PTB suspects in an environment with intermediate burden of PTB and high Bacillus Calmette-Guerin (BCG) vaccination rate. MATERIALS AND METHODS: We retrospectively reviewed IGRA, medical records, chest PA and CT scan of PTB suspects seen at Gangnam Severance Hospital, Seoul, Korea from Oct. 2007 to Apr. 2013. "Active PTB" was diagnosed when 1) M. tuberculosis culture positive, 2) confirmation by pathologic examination; or 3) clinical findings compatible with TB. RESULTS: Of 224 sputum smear negative PTB suspects, 94 were confirmed as having active PTB. There were no statistically significant differences in the diagnostic yield of IGRA between immunocompromised and immunocompetent sputum smear negative PTB suspects. IGRA did show superior sensitivity [81.9%, 95% confidence interval (CI); 74.13-89.70%] in the diagnosis of sputum smear negative PTB when compared with chest high-resolution computed tomography (HRCT), tuberculin skin test (TST), and chest X-ray (p<0.001). Also, IGRA showed highest negative predictive value (82.7%, 95% CI; 75.16-90.15%) when compared with HRCT, TST and chest X-ray (p=0.023). However, combining the results of IGRA with those of HRCT, TST, or both did not increase any diagnostic parameters. CONCLUSION: Failure to increase diagnostic yields by combination with other diagnostic modalities suggests that additional enforcement with IGRA may be insufficient to exclude other diagnoses in sputum smear negative PTB suspects and to screen active PTB in an environment with intermediate TB prevalence and a high BCG vaccination rate.ope

Fiberoptic bronchoscopy for the rapid diagnosis of smear-negative pulmonary tuberculosis.

BACKGROUND: This study was aimed to investigate the diagnostic value of fiberoptic bronchoscopy (FOB) with chest high-resolution computed tomography (HRCT) for the rapid diagnosis of active pulmonary tuberculosis (PTB) in patients suspected of PTB but found to have a negative sputum acid-fast bacilli (AFB) smear. METHODS: We evaluated the diagnostic accuracy of results from FOB and HRCT in 126 patients at Gangnam Severance Hospital (Seoul, Korea) who were suspected of having PTB. RESULTS: Of 126 patients who had negative sputum AFB smears but were suspected of having PTB, 54 patients were confirmed as having active PTB. Hemoptysis was negatively correlated with active PTB. Tree-in-bud appearance on HRCT was significantly associated with active PTB. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FOB alone was 75.9%, 97.2%, 95.3%, and 84.3%, respectively, for the rapid diagnosis of active PTB. The combination of FOB and HRCT improved the sensitivity to 96.3% and the NPV to 96.2%. CONCLUSIONS: FOB is a useful tool in the rapid diagnosis of active PTB with a high sensitivity, specificity, PPV and NPV in sputum smear-negative PTB-suspected patients. HRCT improves the sensitivity of FOB when used in combination with FOB in sputum smear-negative patients suspected of having PTB.ope

The Clinical and Pathologic Features according to Expression of Acyl Protein Thioesterase-1 (APT1) in Stage I Non-small Cell Lung Cancer

BACKGROUND: Acyl protein thioesterase-1 (APT1) is a cytosolic protein that may function in the depalmitoylation of numerous proteins, including the Ras family. However, the clinical role of depalmitoyl thioesterase in human cancer is not known. We evaluated the APT1 expression in lung cancer tissue and its clinicopathological findings according APT1 expression pattern. METHODS: APT1 expression was examined by immunohistochemistry in the tumor tissue from 79 patients, who had undergone curative surgical removal of the primary lesion; all patients had been diagnosed with stage I non-small cell lung cancer between 1993 and 2004, at Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. RESULTS: The APT1 expression was seen in 50 out of 79 (63.3%) cases. The positive APT1 expression was significantly related with histologic subtype and T stage, but was not influenced by differentiation. The positive APT1 expression was not significantly related to patient age, gender, or smoking history. The median follow-up duration was 10.0 years; the 5-year survival rate was 71.0%. The positive APT1 expression group showed significantly worse overall survival and worse disease-free survival without statistical significance. CONCLUSION: We conclude that positive APT1 expression in stage I lung cancer after surgery is closely associated with overall survival. To evaluate APT1 as a prognostic marker in lung cancer, comprehensive studies on advanced stage cases are needed.ope

Stress Related Cardiomyopathy during Flexible Bronchoscopy

Flexible bronchoscopy is a safe medical procedure, but the incidence rate of major complications is 0.08-0.3%. Here, we report 2 cases of stress induced cardiomyopathy, which developed immediately after flexible bronchoscopy. Stress related cardiomyopathy was confirmed by EKG, echocardiography, and coronary angiogram. The cardiac functions of these patients were fully recovered with conservative treatment. Although, the pathogenesis of stress related cardiomyopathy is not well understood, post-bronchoscopy tachycardia or arrhythmia is thought to be associated with hypoxemia or catecholamine excess. Because the clinical presentation is quite similar to acute myocardial infarction, discrete evaluations are required for appropriate treatment.ope

Clinical outcomes of tigecycline in the treatment of multidrug-resistant Acinetobacter baumannii infection

PURPOSE: Acinetobacter baumannii (A. baumannii) has emerged as a major cause of nosocomial pneumonia and sepsis in seriously ill patients. Multidrug-resistant A. baumannii (MDRAB) is increasing in frequency, and the management of it's infections is consequently difficult. Therefore, tigecycline is considered to be the drug of choice for MDRAB treatment. The aim of our study was to evaluate the microbiological eradication and clinical effectiveness of tigecycline against MDRAB in seriously ill patients, including patients with ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: We conducted a retrospective study including patients with A. baumannii infections who were treated with tigecycline between April 1, 2009 and March 31, 2010. We treated 27 patients with tigecycline for MDRAB infections. RESULTS: The mean age of patients was 66.2 years, and 20 (74.1%) patients were male. The median length of stay at hospital was 74.6 days. MDRAB was eradicated from the site of infection in 23 cases (85.2%), however, only 17 cases (63.0%) showed positive clinical responses. Overall, an in-hospital mortality rate of 51.9% was observed, and 4 cases of death were attributable to sepsis. The combination therapy showed better clinical and microbial success rates than the monotherapy without significant difference. CONCLUSION: We observed the relatively low clinical success rate although the microbial eradication rate was high, probably due to superinfections in VAP and bacteremia. We suggest that clinicians should limit tigecycline monotherapy for MDRAB infection in critically ill patients, until large controlled clinical trials should be conducted.ope

Late respiratory infection after lung transplantation

Background : Aiming to improve outcome of lung transplantation (LTx) patients, we reviewed risk factors and treatment practices for the LTx recipients who experienced respiratory infection in the late post-LTx period (＞1 month after LTx). Materials and Methods : We analyzed the clinical data of 48 recipients and donors from 61 LTx, who experienced late respiratory infections. Late respiratory infections were classified according to the etiology, time of occurrence, and frequency of donor-to-host transmission or colonization of the recipient prior to transplantation. Results : During the period of observation, 42 episodes of respiratory infections occurred. The organisms most frequently involved were gram (−) bacteria: Acinetobacter baumannii (n=13, 31.0%), Pseudomonas aeruginosa (n=7, 16.7%), and Klebsiella pneumoniae (n=4, 10.0%). Among the 42 episodes recorded, 14 occurred in the late post-LTx period. These were bacterial (n=6, 42.9%), fungal (n=2, 14.3%), viral (n=4, 28.5%), and mycobacterial (n=2, 14.3%) infections. Of 6 bacterial infections, 2 were from multidrug-resistant (MDR) A. baumannii and one from each of MDR P. aeruginosa, extended spectrum β-lactamase (＋) K. pneumoniae, methicillin-resistant Staphylococcus aureus and Streptococcus pneumoniae. Infection-related death occurred in 6 of the 14 episodes (43%). Conclusion : Although the frequency of respiratory infection decreased sharply in the late post-LTx period, respiratory infection was still a major cause of mortality. Gram (−) MDR bacteria were the agents most commonly identified in these infections.ope

폐손상에서 Romo1에 의하여 유발되는 미토콘드리아 활성산소의 역할 규명

Dept. of Medicine/박사Reactive oxygen species (ROS) modulator 1 (Romo1) is localized in the outer membrane of mitochondria and increases mitochondrial ROS production through complex III mitochondrial electron transport chain. However, the role of Romo1-mediated mitochondrial ROS production in lung epithelial cell apoptosis and lung injury has not been identified yet. In this study, we investigated the role of Romo1 as a mediator in mitochondrial ROS production and apoptotic cell death induced by oxidative stress in lung epithelial cells.H2O2 treatment increased cellular ROS levels and Romo1 expression. Romo1 knockdown blocked H2O2-induced ROS production. H2O2 treatment induced death of BEAS-2B cells in a time- and a dose-dependent manner, and it was inhibited by Romo1 knockdown. The terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling (TUNEL)-stained apoptotic bodies were significantly less in the BEAS-2B cells transfected with Romo1 siRNA compared with control siRNA transfected cells. The Romo1 knockdown inhibited expression of cleaved PARP and γH2AX, which were induced by H2O2 treatment. These findings suggest that Romo1 is an important mediator of apoptotic cell death induced by H2O2 treatment. The TUNEL-positive alveolar epithelial cells were detected in most idiopathic pulmonary fibrosis (IPF) tissues, whereas not observed in normal appearing lung tissues. Also, Romo1 overexpression of alveolar epithelial cells were detected in most IPF tissue, but not observed in normal controls. In conclusion, Romo1 knockdown suppressed the cellular ROS levels increased by exogenous H2O2 in lung epithelial cells. We observed that decreased ROS levels by Romo1 knockdown inhibited cell death by oxidative stress with exogenous H2O2. These results suggest that Romo1-induced ROS play an important role in cell death mechanism in lung epithelial cells.restrictio

석유화학산업 보수 작업 근로자의 1,3-부타디엔 노출특성에 관한 연구

Thesis(masters) --서울대학교 보건대학원 :환경보건학과(산업보건전공),2010.2.Maste

(A)Study of improvements of regulatory alternatives on the misleading effects of TV Home-Shopping Channels : focusing on consumer survey, government assessments and consumer damage cases analysis

학위논문(석사)--서울대학교 대학원 :소비자학과,2005.Maste

비율이 다른 Hydroxyapatite - chitosan 차단막이 백서 두개골 결손부 치유에 미치는 영향

Dept. of Dental Science/박사[한글]차단막을 이용한 조직유도재생술이 골재생을 위한 방법으로 제시되어 왔다. 흡수성 차단막은 흡수속도 조절이 어렵고 염증반응의 우려가 있으나, 비흡수성 차단막에 비해 2차수술을 하지 않아도 된다는 장점이 있다. 한편, 키토산 (chitosan, CS)은 생분해가 가능하고 독성이 없는 중합체로서 생체적합성이 우수한 것으로 알려져 있으며 치주 병소에 적용하는 연구가 지속되고 있다. Hydroxyapatite (HA)는 인체의 뼈를 구성하는 성분 중 하나로, 치과와 정형외과 분야에서 활용되고 있는 골대체제이다. 딱딱하고 부러지기 쉬운 HA의 단점을 보강하기 위해 나노입자 형태로 변형시킨 후, 키토산과의 시너지 효과를 얻고자 HA-CS복합섬유를 개발하였다. 본 연구에서는 백서 두개골에 다양한 농도의 HA-CS 차단막을 이식하여, HA-CS의 비율에 따른 골형성량을 비교하고자 하였다. 70마리의 백서를, 1) 키토산 (CS) 100% 차단막, 2) HA 30%/CS 70% 차단막, 3) HA 40%/CS 60% 압축 차단막, 4) HA 40%/CS 60% 차단막, 5) HA 50%/CS 50% 차단막, 6) HA 50%/CS 50% 압축 차단막, 7) 아무것도 이식하지 않은 대조군 그룹으로 나누어. 각각의 차단막을 백서 두개골의8㎜ 원형 결손부에 이식하였다. 이를 술후 2주, 8주에 희생하여 치유 결과를 조직학 및 조직계측학적으로 비교 관찰하였다. 그 결과 HA-CS 차단막은 rat calvarial defect에서 대조군에 비해 많은 골형성을 나타내었다. 또한 HA 함유량이 가장 많은 실험 5군과 6군에서는, HA 함량이 적은 실험군에 비해 초기 2주차 골생성량이 유의하게 더 많았다. 결론적으로, HA-CS 차단막은 생체재료의 장점을 가지고 있으며, 치주조직의 재생치료에 효과적으로 사용될 수 있을 것으로 보인다. 그러나, HA-CS 차단막이 확실한 scaffold 역할을 할 수 있기 위해서는, 향후 기계적 물성의 개선을 위한 연구가 더 필요하다. [영문]Absorbable membranes are being evaluated as potential candidates for periodontal and bone regeneration therapy. Absorbable membranes have poor membrane stability in the wet state and may cause space loss but do not need to undergo a second surgery, and membrane exposure is rare. Recently, interest in chitosan has increased due to its excellent biological properties such as biocompatibility, antibacterial effect, and rapid healing capacity. On the other hand, hydroxyapatite is used as a bone substitute in the fields of orthopedics and dentistry. The hydroxyapatite-chitosan (HA-CS) complex containing hydroxyapatite nanoparticles was developed for synergy of both biomaterials. The objective of this study was to evaluate the effect of hydroxyapatite (HA)-chitosan (CS) membrane on bone regeneration in the rat calvarial defect. Eight-millimeter critical-sized calvarial defects were created in 70 male Sprague-Dawley rats. The animals were divided into 7 groups of 10 animals and received either 1) chitosan (CS) 100% membrane, 2) hydroxyapatite (HA) 30%/CS 30% membrane, 3) HA 40%/CS 60%, pressed membrane, 4) HA 40%/CS 60% membrane, 5) HA 50%/CS 50% membrane, 6) HA 50%/CS 50%, pressed membrane, or 7) a sham ? surgery control. The amount of newly formed bone from the surface of the rat calvarial defects was measured using histomorphometry and following 2- or 8- week healing intervals. Surgical implantation of the HA-CS membrane resulted in enhanced local bone formation at both 2 and 8 weeks compared to the control group. The HA-CS membrane would be significantly more effective than the chitosan membrane in early bone formation. Further studies will be required to improve the mechanical properties to develop a more rigid scaffold for the HA-CS membrane. In conclusion, concerning the advantages of biomaterials, the HA-CS membrane would be an effective biomaterial for regeneration of periodontal bone.ope