Jeong Woong Park

Effects of ambient particulate matter on peak expiratory flow rates and respiratory symptoms of asthmatics during Asian dust periods in Korea

Objective:  Dust generating events frequently produce ambient dust particles that are less than 10 µm in diameter, and these have been linked to adverse effects in the general population. However, the evidence linking these particles to adverse effects on the airways of asthmatic individuals is limited. The objective of this study was to investigate the possible adverse effects of Asian dust events on the respiratory functions and symptoms of subjects with bronchial asthma.

Randomized phase II trial of two different schedules of docetaxel plus cisplatin as first‐line therapy in advanced nonsmall cell lung cancer

There is increasing interest in the use of a weekly administration of docetaxel as a way of reducing its hematologic toxicity. The purpose of the current randomized study was to evaluate the toxicity and efficacy of docetaxel plus cisplatin combination on 2 schedules in patients with previously untreated, advanced nonsmall‐cell lung cancer (NSCLC).

Pemetrexed versus gefitinib versus erlotinib in previously treated patients with non-small cell lung cancer.

Background/Aims The efficacy and safety of pemetrexed, gefitinib, and erlotinib administration in previously treated patients with non-small cell lung cancer (NSCLC) were compared. Methods The study patients met the following criteria: histologically confirmed, previously treated advanced (stage IIIB or IV) or recurrent NSCLC; a measurable lesion; ≥ 18 years of age; Eastern Cooperative Oncology Group Performance status 0 to 2; and no prior exposure to the three study drugs. Patients received 500 mg/m2 of pemetrexed intravenously every 3 weeks with vitamin supplementation, gefitinib (250 mg/day per os), or erlotinib (150 mg/day per os). Results Of 57 patients (pemetrexed, 20; gefitinib, 20; and erlotinib, 17), 55 were evaluated for a response. The numbers of males, smokers, and squamous histology were increased in the pemetrexed group compared to the other groups. The objective response rates were 5.3%, 25.0%, and 12.5% (p = 0.22), and the disease control rates (DCR) were 5.3%, 40.0%, and 50.0%, respectively (p < 0.01). The median progression-free survival (PFS) was 1.7, 3.5, and 4.4 months (p < 0.01) and the median overall survival (OS) was 5.6, 21.8, and 21.5 months (p = 0.04), respectively. In subgroup analyses, patients with non-squamous histology, males, and a smoking history had a higher DCR and longer PFS with gefitinib and erlotinib than with pemetrexed. All three chemotherapeutic agents had manageable toxicities. Conclusions Both oral epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) had comparable efficacy and safety. The superior PFS and OS of EGFR TKIs with more favorable baseline clinical characteristics than those of pemetrexed suggest the impact of baseline clinicopathological factors.

Comparison of sputum and nasopharyngeal swabs for detection of respiratory viruses

Diagnostic tests for respiratory viral infections use traditionally either nasopharyngeal washes or swabs. Sputum is representative of the lower respiratory tract but is used rarely for viral testing. The aim of this study was to compare the detection rates of respiratory viruses from nasopharyngeal swabs and sputum using a multiplex real‐time reverse transcription‐polymerase chain reaction (RT‐PCR). Adults who were admitted or presented to the clinics of Gil Medical Center with acute respiratory symptoms were recruited from 1 November 2012 to 31 March 2013. Paired specimens of nasopharyngeal swabs and sputum were obtained from 154 subjects, and RNA was extracted and tested for 16 different respiratory viruses using the Anyplex II RV16 Detection kit (Seegene, Seoul, Korea). The positive rate was 53% (81/154) for nasopharyngeal swabs and 68% (105/154) for sputum (P < 0.001). One hundred thirty‐four viruses were identified for 107 illnesses. Influenza A virus, RSV A, HRV, coronavirus OC43, and adenovirus were detected more frequently in sputum samples than in nasopharyngeal swabs (P < 0.001). Importantly, 12 of 44 (27%) influenza A infections and 11 of 27 (41%) RSV infections were positive in only sputum samples. The detection rates of respiratory viruses from sputum samples were significantly higher than those from nasopharyngeal swabs in adults using real‐time multiplex RT‐PCR. These findings suggest that sputum would benefit for the detection of respiratory viruses by nucleic acid amplification tests (NAATs) in patients who produce sputum. Further studies are needed to establish standardized RNA extraction methods from sputum samples. J. Med. Virol. 86:2122–2127, 2014.

A Pilot Study of Intralymphatic Immunotherapy for House Dust Mite, Cat, and Dog Allergies.

Several recent clinical trials reported that intralymphatic immunotherapy (ILIT) for some allergens, such as cat dander and pollen, induce tolerance more rapidly than conventional subcutaneous or sublingual immunotherapy, have a comparable duration of effect after only 3 injections, and do not provoke serious local or systemic reactions. However, the efficacy and safety of ILIT are using Dermatophagoides farinae (Df), Dermatophagoides pteronyssinus (Dp), and dog, which are indoor allergens that are commonly found globally, need to be evaluated. Furthermore, use of multiple allergens in ILIT should be investigated. We assessed the clinical efficacy and adverse effects of ILIT using aqueous Df, Dp, dog, and cat allergens or mixtures thereof in patients with allergic rhinitis. A total of 11 subjects with AR sensitized to Df, Dp, cat, and/or dog allergens received 3 intralymphatic inguinal injections of sensitized allergen extract (HollisterStier, New Orleans, LA, USA). Clinical parameters were assessed before ILIT, and 4 months and 1 year after the first injection. Rhinitis symptoms were alleviated and quality of life was improved 4 months after ILIT (P=0.012 and P=0.007, respectively), and these improvements lasted for 1 year after ILIT (P=0.047 and P=0.009, respectively). However, we observed 2 cases of anaphylaxis, one case of a moderate-to-severe systemic hypersensitivity reaction and the other case of a severe local reaction at the injection site after ILIT. In conclusion, ILIT can rapidly improve allergy symptoms and quality of life, and this effect lasts for 1 year. In hypersensitized patients, however, ILIT can provoke severe systemic and/or local hypersensitivity reactions when performed using aqueous allergen extracts.

Effect of a Dose-Escalation Regimen for Improving Adherence to Roflumilast in Patients with Chronic Obstructive Pulmonary Disease

Background The adverse effects of the phosphodiesterase-4 inhibitor roflumilast, appear to be more frequent in clinical practice than what was observed in chronic obstructive pulmonary disease (COPD) clinical trials. Thus, we designed this study to determine whether adverse effects could be reduced by starting roflumilast at half the dose, and then increasing a few weeks later to 500 µg daily. Methods We retrospectively investigated 85 patients with COPD who had taken either 500 µg roflumilast, or a starting dose of 250 µg and then increased to 500 µg. We analyzed all adverse events and assessed differences between patients who continued taking the drug after dose escalation and those who had stopped. Results Adverse events were reported by 22 of the 85 patients (25.9%). The most common adverse event was diarrhea (10.6%). Of the 52 patients who had increased from a starting dose of 250 µg roflumilast to 500 µg, 43 (82.7%) successfully maintained the 500 µg roflumilast dose. No difference in factors likely to affect the risk of adverse effects, was detected between the dose-escalated and the discontinued groups. Of the 26 patients who started with the 500 µg roflumilast regimen, seven (26.9%) discontinued because of adverse effects. There was no statistically significant difference in discontinuation rate between the dose-escalated and the control groups (p=0.22). Conclusion Escalating the roflumilast dose may reduce treatment-related adverse effects and improve tolerance to the full dose. This study suggests that the dose-escalated regimen reduced the rate of discontinuation. However, longer-term and larger-scale studies are needed to support the full benefit of a dose escalation strategy.

Asian Dust Particles Induce TGF-β1 via Reactive Oxygen Species in Bronchial Epithelial Cells

Background Asian dust storms can be transported across eastern Asia. In vitro, Asian dust particle-induced inflammation and enhancement of the allergic reaction have been observed. However, the fibrotic effects of Asian dust particles are not clear. Production of transforming growth factor β1 (TGF-β1) and fibronectin were investigated in the bronchial epithelial cells after exposure to Asian dust particulate matter (AD-PM10). Methods During Asian dust storm periods, air samples were collected. The bronchial epithelial cells were exposed to AD-PM10 with and without the antioxidant, N-acetyl-L-cysteine (NAC). Then TGF-β1 and fibronectin were detected by Western blotting. The reactive oxygen species (ROS) was detected by the measurement of dicholorodihydrofluorescin (DCF), using a FACScan, and visualized by a confocal microscopy. Results The expression of TGF-β1, fibronectin and ROS was high after being exposed to AD-PM10, compared to the control. NAC attenuated both TGF-β1 and fibronectin expression in the AD-PM10-exposed the bronchial epithelial cells. Conclusion AD-PM10 may have fibrotic potential in the bronchial epithelial cells and the possible mechanism is AD-PM10-induced intracellular ROS.

Nontuberculous Mycobacteria Isolated from Respiratory Specimens during Recent Two Years: Distribution and Clinical Significance

Background: The isolation of nontuberculous mycobacteria (NTM) has been increasing worldwide as well as its clinical importance. The aim of this study was to investigate the distribution and clinical significance of NTM that has been isolated from respiratory specimens during a recent two-year period at a tertiary hospital. Methods: We analyzed respiratory samples that were obtained between January 2009 and December 2010 for AFB culture. We retrospectively reviewed the electronic medical records of these patients to obtain both clinical and radiologic information. NTM pulmonary disease was defined by using the guidelines provided by the America Thoracic Society/Infectious Diseases Society of America. Results: Among the 1,601 specimens that resulted in a positive AFB culture, 310 (19.4%) were NTM. In 189 patients, the most common isolate was M. aviumintracellulare complex (MAC) (127, 67.2%), which was then followed by M. abscessus (31, 16.4%), M. fortuitum (10, 5.3%), M. kansasii (9, 4.8%), and other NTM species. Of these, 93 (49.2%) patients were diagnosed with NTM pulmonary disease. MAC, M. abscessus, and M. kansasii were more virulent than the other species. None of the cases of NTM pulmonary disease were caused by M. fortuitum, M. chelonae, M. peregrinum, M. terrae complex, or M. gordonae. Conclusion: In Korea, the prevalence of NTM isolates is increasing, as are the cases of pulmonary disease. The pathogenic potential of NTM differs enormously by species and as a result the treatment of NTM lung disease depends on which species has caused the infection. The isolation and identification of NTM isolated from respiratory specimens are mandatory in order for clinical microbiology laboratories to make an accurate diagnosis and suggest the proper treatment of the NTM disease. (Korean J Clin Microbiol 2012;15:98-103)

Phase II trial of weekly docetaxel and gemcitabine for previously untreated, advanced non-small cell lung cancer

Docetaxel and gemcitabine combination chemotherapy has been reported to be active against non-small cell lung cancer (NSCLC) and myelosuppression is the most common dose-limiting toxicity. This prospective phase II study was designed to test the hypothesis that better tolerance and increased dose intensity might be achieved if patients are treated with weekly administration schedule. Thirty-five patients with stage IIIB/IV NSCLC and a performance status 0-2 received first-line chemotherapy with docetaxel 35mg/m2 and gemcitabine 600mg/m2 on days 1, 8 and 15. Treatment was repeated every 4 weeks, for up to 4 cycles. In total, 85 chemotherapy cycles were given (median, 2; range, 1-4). Other than the completion of all 4 planned cycles (n=6), the main reasons for treatment discontinuation were toxicity (n=15) and progressive disease (n=14). The most frequently encountered toxic effects were anemia (52% of patients), nausea and vomiting (60%), fatigue (71%) and anorexia (57%). One patient died of bilateral pneumonitis, which developed shortly after the administration of second cycle. Disease control (objective response and stable disease) in the intent-to-treat (ITT) population was achieved in 60% of patients and the overall response rate was 29% (95% CI, 14-44%). With a median follow-up duration of 13 months, the median progression-free survival and overall survival were 2.8 (95% CI, 0.7-4.8) months and 10.6 (95% CI, 7.0-14.3) months, respectively. In conclusion, weekly schedule of docetaxel and gemcitabine has modest activity with acceptable toxicity profile in advanced NSCLC, but as high frequency of early discontinuation occurred does not merit further study with the present regimen.

Sulforaphane attenuates pulmonary fibrosis by inhibiting the epithelial-mesenchymal transition

BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease with no effective treatment. The epithelial-mesenchymal transition (EMT) is a critical stage during the development of fibrosis. To assess the effect of sulforaphane (SFN) on the EMT and fibrosis using an in vitro transforming growth factor (TGF)-β1-induced model and an in vivo bleomycin (BLM)-induced model.MethodsIn vitro studies, cell viability, and cytotoxicity were measured using a Cell Counting Kit-8. The functional TGF-β1-induced EMT and fibrosis were assessed using western blotting and a quantitative real-time polymerase chain reaction. The lungs were analyzed histopathologically in vivo using hematoxylin and eosin and Masson’s trichrome staining. The BLM-induced fibrosis was characterized by western blotting and immunohistochemical analyses for fibronectin, TGF-β1, E-cadherin (E-cad), and α-smooth muscle actin (SMA) in lung tissues.ResultsSFN reversed mesenchymal-like changes induced by TGF-β1 and restored cells to their epithelial-like morphology. The results confirmed that the expression of the epithelial marker, E-cadherin, increased after SFN treatment, while expression of the mesenchymal markers, N-cadherin, vimentin, and α-SMA decreased in A549 cells after SFN treatment. In addition, SFN inhibited TGF-β1-induced mRNA expression of the EMT-related transcription factors, Slug, Snail, and Twist. The SFN treatment attenuated TGF-β1-induced expression of fibrosis-related proteins, such as fibronection, collagen I, collagen IV, and α-SMA in MRC-5 cells. Furthermore, SFN reduced the TGF-β1-induced phosphorylation of SMAD2/3 protein in A549 cells and MRC-5 cells. BLM induced fibrosis in mouse lungs that was also attenuated by SFN treatment, and SFN treatment decreased BLM-induced fibronectin expression, TGF-β1 expression, and the levels of collagen I in the lungs of mice.ConclusionsSFN showed a significant anti-fibrotic effect in TGF-β-treated cell lines and BLM-induced fibrosis in mice. These findings showed that SFN has anti-fibrotic activity that may be considered in the treatment of IPF.