Association of moderate-to-vigorous physical activity with reduction of acute exacerbation in COPD patients using a dual ultra-long-acting bronchodilators.

Inhaler therapy and physical activity (PA) are important methods of chronic obstructive pulmonary disease (COPD) management. This study aimed to investigate the additional benefit of moderate-to-vigorous PA (MVPA) in patients with COPD using a long-acting beta-agonists (LABA)/long-acting muscarinic antagonist (LAMA) combination. We emulated a target trial to estimate the benefit of MVPA in patients with COPD using a dual ultra-long-acting bronchodilators. We enrolled patients aged ≥ 40 who were diagnosed with COPD between 2014 and 2018, initiated a LABA/LAMA combination, and had not undergone regular MVPA. The main exposure was the initiation of MVPA, defined as vigorous aerobic exercise > 20 min per day on ≥ 3 days/week or moderate aerobic exercise > 30 min per day on ≥ 5 days/week. The main outcomes were the future usage of inhaled corticosteroids (ICS) and severe exacerbation. We identified 1,526 patients who initiated MVPA and 4,516 who did not. The median follow-up period was 3.0 years. The hazard ratio (HR) for future ICS usage in the MVPA initiation group was 0.83 (95% confidence intervals (CI): 0.72, 0.97) compared to the control group. The HR for severe exacerbation in the MVPA initiation group was 0.81 (95% CI: 0.68, 0.96) compared to the control group. Subgroup analyses by age, sex, body mass index, residence area, smoking and drinking status showed consistent benefits in these outcomes. Initiation of MVPA may offer an additional benefit for even COPD patients who use a dual ultra-long-acting bronchodilators.

Pneumocystis Pneumonia in a Non-Immunocompromised Lung Cancer Patient after Surgery: A Case Report.

We present the Pneumocystis pneumonia case of a 64-year-old man with no remarkable history except for hypertension, who had not undergone any treatment other than surgery. On postoperative day 7, high-resolution computed tomography findings revealed multifocal ground-glass opacifications with interlobular septal thickening in both lungs; therefore, atypical pneumonia was suspected. Polymerase chain reaction (PCR) test performed after bronchoalveolar lavage was positive for Pneumocystis jirovecii (P. jirovecii). Based on the PCR results, a final diagnosis of Pneumocystis pneumonia (PCP) was made. After treatment, he improved and was discharged. This is a unique case of PCP diagnosis in a non-immunocompromised patient, with no remarkable history except for hypertension, who had not undergone any treatment other than surgery for cancer. Thus, it is necessary to consider additional risk factors for PCP and timing of preventive treatment.

Broken Needle Embedded in the Body during Vascular Puncture.

The use of needles is essential in most medical procedures and surgery; however, needle breakage is not known to happen very frequently. Even if it does, it is most likely to occur during dental procedures, sutures, aspiration, biopsy, anesthesia, and drug abuse. To our knowledge, this is the first report about needle detachment from the syringe during a vascular puncture for blood collection. In this case, an 87-year-old obese woman with generalized edema had repeated vascular punctures to the femoral artery for arterial blood gas analysis (ABGA). After blood collection at this instance, when the syringe was pulled out, the needle was detached from it. Radiography revealed that the broken needle was lodged in the groin. A surgical incision with the fluoroscopic radiography located the embedded needle in the soft tissue and allowed the retrieval of its fragments from the groin soft tissue. Obesity and repeated punctures may increase the risk of needle breakage and prior inspection of needles for such procedures may be necessary.

Triple primary lung cancer: a case report.

BACKGROUND: The risk of developing lung cancer is increased in smokers, patients with chronic obstructive pulmonary disease, individuals exposed to environmental carcinogens, and those with a history of lung cancer. Automobile exhaust fumes containing carcinogens are a risk factor for lung cancer. However, we go through life unaware of the fact that automobile exhaust is the cause of cancer. Especially, in lung cancer patient, it is important to search out pre-existing risk factors and advice to avoid them, and monitor carefully for recurrence after treatment. CASE PRESENTATION: This is the first report of a case with triple lung cancers with different histologic types at different sites, observed in a 76-year-old parking attendant. The first adenocarcinoma and the second squamous cell carcinoma were treated with stereotactic radiosurgery because the patient did not want to undergo surgery. Although the patient stopped intermittent smoking after the diagnosis, he continued working as a parking attendant in the parking lot. After 29 months from the first treatment, the patient developed a third new small cell lung cancer; he was being treated with chemoradiation. CONCLUSIONS: New mass after treatment of lung cancer might be a multiple primary lung cancer rather than metastasis. Thus, precision evaluation is important. This paper highlights the risk factors for lung cancer that are easily overlooked but should not be dismissed, and the necessity of discussion with patients for the surveillance after lung cancer treatment. We should look over carefully the environmental carcinogens already exposed, and counsel to avoid pre-existing lung cancer risk factors at work or residence in patients with lung cancer.

Pulmonary cryptococcosis after recovery from COVID-19 in an immunocompetent patient: A rare case report.

RATIONALE: Cryptococcus neoformans (C neoformans) infection typically occurs in immunocompromised patients infected with human immunodeficiency virus (HIV), or those taking immunosuppressive drugs, corticosteroids, or chemotherapy. Recently, there have been an increasing number of reports of cryptococcosis as opportunistic infections in COVID-19 patients, all of which have been related to immunocompromising conditions, underlying medical diseases, immune suppression drugs, or corticosteroids. Here, we report the first case of pulmonary cryptococcosis in an immunocompetent patient with a history of COVID-19 who had no history of underlying diseases or immune modulation drugs. PATIENT CONCERNS: A previously healthy 46-year-old man presented with tiny lung nodules. He had quit smoking 6 years prior. He had no significant medical history except for COVID-19 3 months prior, and had not received corticosteroids or cytokine blockers when he had COVID-19. He had been coughing since he recovered from COVID-19. DIAGNOSIS: Bronchoalveolar lavage cultures showed the growth of C neoformans. A CT-guided percutaneous needle biopsy of the lung lesion was performed. Histopathology of the biopsy specimen showed granulomas with encapsulated yeast. There was no growth of C neoformans in the CSF or blood. He was diagnosed with pulmonary cryptococcosis. INTERVENTION: Antifungal drug (fluconazole) was administered for 6 months in the outside clinic. OUTCOMES: The lung lesions disappeared after 6 months medication. LESSONS: This case may illustrate the risk of pulmonary cryptococcosis after SARS-CoV-2 infection in an immunocompetent patient. Opportunistic infections can occur even after recovery from COVID-19 for several reasons. First, SARS-CoV-2 infection causes immune dysregulation including lymphocytopenia. Second, T lymphocytes play a principal role against Cryptococcus. Third, these changes in the immune system due to COVID-19 may last for several weeks. Thus, we suggest careful consideration of lung lesions in patients with a history of COVID-19.

Radiation-induced pseudomembranous tracheobronchitis: A report of two cases.

Radiation therapy can cause radiation pneumonitis, organizing pneumonia, and lung fibrosis. Radiation-induced pseudomembranous bronchitis is a rare condition. Here, we describe a rare case each of pseudomembranous tracheobronchitis and pseudomembrane with total bronchial obstruction which developed after thoracic radiotherapy. A 50-year-old man presented paroxysmal severe cough 1 month after concurrent chemoradiotherapy for small-cell lung cancer. Bronchoscopy revealed a whitish membrane in the trachea and bronchus, which were the fields of radiation. Another 60-year-old man complained of dyspnea 7 months after radiation therapy for metastatic lymph node adenocarcinoma. Bronchoscopy demonstrated a membrane with total obstruction of right lower lobar bronchus, which was the area of radiation. The pathological findings of histological examination in both cases demonstrated radiation-induced pseudomembranous tracheobronchitis. Patients in both cases responded well to steroids and the pseudomembrane disappeared. If patients who have received thoracic radiation therapy complain of persistent cough, bronchoscopy may be helpful.

Association Between Vitamin D Level and Respiratory Symptoms in Patients with Stable Chronic Obstructive Pulmonary Disease.

Purpose: Vitamin D insufficiency or deficiency is prevalent in patients with chronic obstructive pulmonary disease (COPD). However, the association between vitamin D levels and respiratory symptoms in patients with stable COPD has not been fully investigated. This study evaluated the association between vitamin D levels and respiratory symptoms in patients with stable COPD. Patients and Methods: Patients with COPD who had their serum 25-hydroxyvitamin D (25-OH vitamin D) level measured within 6 months of spirometry between January 2016 and April 2020 were retrospectively included. Respiratory symptoms were assessed using the modified Medical Research Council (mMRC) scale and COPD assessment test (CAT) score. Results: Of the 329 included patients, 193, 88, and 48 were categorized as having vitamin D deficiency (<20 ng/mL), insufficiency (20-29 ng/mL), and sufficiency (≥30 ng/mL), respectively. The mean serum 25-OH vitamin D level of each group was 13.45 ng/mL, 24.61 ng/mL, and 38.90 ng/mL, respectively. Patients with vitamin D insufficiency/deficiency showed higher CAT scores than those with vitamin D sufficiency (p = 0.004). In multivariable adjusted models, vitamin D insufficiency/deficiency was significantly associated with a CAT score of 10 or more (adjusted odds ratio [aOR] = 2.41, 95% confidence interval [CI] = 1.20-4.82, p = 0.013) and mMRC ≥ 2 (aOR = 2.39, 95% CI = 1.08-5.32, p = 0.032). Among CAT items, the amount of phlegm (p = 0.008), chest tightness (p = 0.030), breathlessness walking upstairs (p < 0.001), home activity limitations (p = 0.002), and lack of energy (p = 0.003) were significantly associated with vitamin D insufficiency/deficiency after adjustment for age, sex, body mass index, smoking history, Charlson comorbidity index, post-bronchodilator forced expiratory volume in 1 second, and season of blood draw. Conclusion: Vitamin D insufficiency/deficiency were associated with worse respiratory symptoms in patients with stable COPD.

A pilot investigation of e-cigarette use and smoking behaviour among patients with chronic airway disease or respiratory symptoms.

BACKGROUND: This pilot study aimed to investigate the current status of e-cigarettes (ECs) use patterns among patients with chronic airway disease or chronic respiratory symptoms and the effects of ECs use on respiratory and mental health. METHODS: A cross-sectional survey was conducted at the outpatient clinic of eight teaching hospitals in South Korea between November 2019 and December 2019. All adult ECs users (19 years and above) who visited the outpatient clinic as a patient with chronic airway disease or chronic respiratory symptoms were eligible to participate in this study. RESULTS: A total of 51 subjects responded to the survey. Most of the participants were male (92.2%) and the mean age was 41.8 years. Dominant airway diseases were asthma and chronic obstructive pulmonary disease. Most of the subjects had a history of cigarette smoking, and 19 subjects were dual users of current cigarettes and ECs. Most of the subjects started ECs use due to health-related reasons. When comparing exclusive ECs users and dual users, St. George's respiratory questionnaire (SGRQ) scores, the proportion of cases with moderate to severe depressive symptoms, and average Fagerstrom test for nicotine dependence scores for ECs were higher in dual users than exclusive ECs users (mean 4.64 vs. 2.38, p = 0.006), respectively. CONCLUSION: Most of the subjects started ECs use due to health concerns, but dual users have more respiratory symptoms and higher nicotine dependence in this pilot study. One hypothesis that comes from these results is that greater nicotine dependence may influence behaviours, habits, and views about ECs. These preliminary observations need confirmation in a large cohort.

E-cigarette-associated Severe Pneumonia in Korea Using Data Linkage between the Korea National Health and Nutrition Examination Survey (KNHANES, 2013-2019) and the National Health Insurance Service (NHIS) Claims Database.

BACKGROUND: This study aimed to investigate the association between e-cigarette (EC) use and development of acute severe pneumonia in the Korean population using a national database. METHODS: We conducted a retrospective analysis using linkage of data between the Korean National Health and Nutrition Examination Survey (KNHANES) and the National Health Insurance Service (NHIS) administrative claims database. The primary endpoint of this study was development of severe pneumonia requiring hospital admission according to EC use during the study period. The secondary endpoints were in-hospital mortality, intensive care unit (ICU) admission, ventilator care, and days of hospital stay. RESULTS: The final analysis included 28,950 individuals, of which 578 (2.0%) were EC users. EC users were younger and more often male than non-EC users. The EC users showed higher level of education and household income and had fewer comorbidities. Severe pneumonia was noted in 37 of 28,372 non-EC users (0.13%), but there were no occurrences of severe pneumonia in EC users. The incidence of pneumonia occurrence was not different between the two groups (P = 1.000). CONCLUSIONS: Since e-cigarette or vaping use-associated lung injury (EVALI) is most likely included in acute severe pneumonia occurring within 3 months of EC use, it is considered that there might be no EVALI patients in Korea during the investigation period. A large-scale, prospective study is necessary to evaluate the association between EC use and acute lung injury.

Pharmacokinetics and Monte Carlo Simulation of Meropenem in Critically Ill Adult Patients Receiving Extracorporeal Membrane Oxygenation.

Objectives: There have been few clinical studies of ECMO-related alterations of the PK of meropenem and conflicting results were reported. This study investigated the pharmacokinetics (PK) of meropenem in critically ill adult patients receiving extracorporeal membrane oxygenation (ECMO) and used Monte Carlo simulations to determine appropriate dosage regimens. Methods: After a single 0.5 or 1 g dose of meropenem, 7 blood samples were drawn. A population PK model was developed using nonlinear mixed-effects modeling. The probability of target attainment was evaluated using Monte Carlo simulation. The following treatment targets were evaluated: the cumulative percentage of time during which the free drug concentration exceeds the minimum inhibitory concentration of at least 40% (40% fT>MIC), 100% fT>MIC, and 100% fT>4xMIC. Results: Meropenem PK were adequately described by a two-compartment model, in which creatinine clearance and ECMO flow rate were significant covariates of total clearance and central volume of distribution, respectively. The Monte Carlo simulation predicted appropriate meropenem dosage regimens. For a patient with a creatinine clearance of 50-130 ml/min, standard regimen of 1 g q8h by i. v. infusion over 0.5 h was optimal when a MIC was 4 mg/L and a target was 40% fT>MIC. However, the standard regimen did not attain more aggressive target of 100% fT>MIC or 100% fT>4xMIC. Conclusion: The population PK model of meropenem for patients on ECMO was successfully developed with a two-compartment model. ECMO patients exhibit similar PK with patients without ECMO. If more aggressive targets than 40% fT>MIC are adopted, dose increase may be needed.

Favorable Response to Long-Term Azithromycin Therapy in Bronchiectasis Patients with Chronic Airflow Obstruction Compared to Chronic Obstructive Pulmonary Disease Patients without Bronchiectasis.

PURPOSE: Long-term macrolide treatment is recommended for patients with chronic obstructive pulmonary disease (COPD) with frequent exacerbations. Bronchiectasis is a common comorbid condition in patients with COPD, for which long-term azithromycin is effective in preventing exacerbation. This study aimed to compare the effect of long-term azithromycin between bronchiectasis patients with chronic airflow obstruction (CAO) and COPD patients without bronchiectasis. PATIENTS AND METHODS: Patients with CAO who received azithromycin for more than 12 weeks were retrospectively identified at a single referral hospital. CAO was defined as a post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) <0.7, and bronchiectasis was determined using computed tomography. The development of exacerbation and symptom improvement were compared between bronchiectasis patients with CAO and COPD patients without bronchiectasis. RESULTS: A total of 59 patients (43 in bronchiectasis with CAO group vs 16 in COPD without bronchiectasis group) were included in this study. Compared to COPD patients without bronchiectasis, those in bronchiectasis with CAO group were younger, more likely to be female, and never smokers. There was no difference in the previous exacerbation history or FEV1 between the two groups. The median duration of azithromycin treatment was 15 months (interquartile range, 8-25 months). At the 12-month follow-up, the development of ≥2 moderate or ≥1 severe exacerbations was significantly lower in bronchiectasis with CAO group than in COPD without bronchiectasis group (46.5% vs 87.5%, P = 0.005). The proportion of patients with symptom improvement determined by the COPD assessment test score was also significantly higher in bronchiectasis with CAO group than COPD without bronchiectasis group at the 12-month follow-up (68.2% vs 16.7%, P = 0.004). CONCLUSION: Bronchiectasis patients with CAO could benefit more from long-term azithromycin treatment than COPD patients without bronchiectasis.

Understanding racial differences of COPD patients with an ecological model: two large cohort studies in the US and Korea.

BACKGROUND: There are limited data about the racial difference in the characteristics of chronic obstructive pulmonary disease (COPD) patients who are treated at clinics. We aimed to compare sociodemographic and clinical characteristics between US and Korean COPD patients using large-scale nationwide COPD cohorts. METHODS: We used the baseline demographic and clinical data of COPD patients aged 45 years or older with at least a 10 pack-per year smoking history from the Korean COPD Subtype Study (KOCOSS, n = 1686) cohort (2012-2018) and phase I (2008-2011) of the US Genetic Epidemiology of COPD (COPDGene) study (n = 4477, 3461 were non-Hispanic whites [NHW], and 1016 were African Americans [AA]). RESULTS: Compared to NHW, AA had a significantly lower adjusted prevalence ratio (aPR) of cough >3 months (aPR: 0.67; 95% CI [confidence interval]: 0.60-0.75) and phlegm >3 months (aPR: 0.78, 95% CI: 0.70-0.86), but higher aPR of dyspnea (modified Medical Round Council scale ⩾2) (aPR: 1.22; 95% CI: 1.15-1.29), short six-minute walk distance (<350 m) (aPR: 1.98; 95% CI: 1.81-2.14), and poor quality of life (aPR: 1.10; 95% CI: 1.05-1.15). Compared to NHW, Koreans had a significantly lower aPR of cough >3 months (aPR: 0.53; 95% CI: 0.47-0.59), phlegm >3 months (aPR: 0.75; 95% CI: 0.67-0.82), dyspnea (aPR: 0.72; 95% CI: 0.66-0.79), and moderate-to-severe acute exacerbation in the previous year (aPR: 0.73; 95% CI: 0.65-0.82). NHW had the highest burden related to chronic bronchitis symptoms and cardiovascular diseases related to comorbidities. CONCLUSION: There are substantial differences in sociodemographic characteristics, clinical presentation, and comorbidities between COPD patients from the KOCOSS and COPDGene, which might be caused by interactions between various intrapersonal, interpersonal, and environmental factors of the ecological model. Thus, a broader and more comprehensive approach would be necessary to understand the racial differences of COPD patients.

Nicotine Dependence and Stress Susceptibility in E-Cigarette Smokers: The Korea National Health and Nutrition Examination Survey 2013-2017.

BACKGROUND: E-cigarettes are steadily gaining popularity in Korea. However, the characteristics of e-cigarette smokers, especially nicotine dependence and stress susceptibility, have not been evaluated in comparison to those of non-smokers or combustible cigarette smokers in Korea. METHODS: In this study, 28,059 participants from the Korea National Health and Nutrition Examination Survey (2013-2017) were classified into the following three groups: non-smokers, smokers (current smokers and ex-smokers of combustible cigarettes only), and e-smokers (current smokers and ex-smokers of e-cigarettes regardless of combustible cigarette use). RESULTS: Among the participants, 16,980 (60.5%), 9,247 (33.0%), and 1,832 (6.4%) subjects were non-smokers, smokers, and e-smokers, respectively. E-smokers were younger, more educated, and had a higher household income than non-smokers or smokers. The number of e-smokers who smoked within 5 minutes of waking up (31.5% vs. 19.8%, p<0.001) and who planned to quit smoking within 6 months (39.1% vs. 35.7%, p<0.05) was greater than that of smokers. E-smokers perceived stress as "very much" (7.0% vs. 4.4%, p<0.001) and "a lot" (29.1% vs. 20.5%, p<0.001) compared to non-smokers. Suicidal ideation (6.5% vs. 4.7%, p<0.001), plans (2.4% vs. 1.3%, p<0.001), and attempts (1.1% vs. 0.5%, p<0.001) were higher in e-smokers than in non-smokers. Depressive episodes in 1 year (14.2% vs. 11.4%, p<0.05) and suicidal plans (2.4% vs. 1.8%, p<0.05) were more frequent among e-smokers than among smokers. CONCLUSION: E-smokers were younger, more educated, and had a higher income, but they were more dependent on nicotine and susceptible to stress than non-smokers and smokers. Smoking cessation counseling should be tailored according to the characteristics of e-smokers.

Longitudinal Changes in Clinical Features, Management, and Outcomes of Idiopathic Pulmonary Fibrosis. A Nationwide Cohort Study.

Rationale: In recent decades, diagnosis and treatment recommendations for idiopathic pulmonary fibrosis (IPF) have changed. In Korea, the average life expectancy has increased, unmet healthcare needs have been reduced, and the number of computed tomographic examinations performed has nearly doubled. The Korean Interstitial Lung Disease Study Group conducted a nationwide cohort study for idiopathic interstitial pneumonia, including IPF, and established a registry for IPF.Objectives: Using study data collected by the study group, this study aimed to evaluate longitudinal changes in clinical features, diagnosis, treatment, and mortality and analyze the extent to which changes in medication usage affected IPF-associated mortality.Methods: The study population included newly diagnosed patients with IPF from a cohort study (January 2002 to September 2008, n = 1,839, 2008 group) and prospective registry (January 2012 to August 2018, n = 1,345, 2018 group). Survival curves were estimated using the Kaplan-Meier method, and Cox regression models were used to identify mortality-associated risk factors in each group.Results: The 2018 group was younger, had fewer symptoms, had less honeycombing, underwent more serologic autoimmune marker and pulmonary function tests, had higher oxygen partial pressure and lower carbon dioxide partial pressure values, was less frequently diagnosed by surgical biopsy, and had better survival than the 2008 group. Steroid use and conservative care declined, whereas N-acetylcysteine use increased in this group. Antifibrotic agents were used in only the 2018 group. In the 2008 group, N-acetylcysteine was associated with lower mortality, whereas conservative care was associated with higher mortality. In the 2018 group, the use of antifibrotic agents was associated with lower mortality, and steroid use was associated with higher mortality. The survival rates in the 2008 and 2018 non-antifibrotic agent subgroups were similar.Conclusions: This study analyzed national IPF cohort data spanning 17 years. In clinical practice, the IPF diagnosis was made earlier, steroid and immunosuppressive agent use was reduced, and antifibrotic agents were administered. The survival of patients with IPF has improved over the decades, and antifibrotic use was consistently associated with improved survival.Clinical trial registered with clinicaltrials.gov (NCT04160715).

Metabolic Syndrome in Early Chronic Obstructive Pulmonary Disease: Gender Differences and Impact on Exacerbation and Medical Costs.

Background: Metabolic syndrome (MetS) is a well-known comorbidity of chronic obstructive pulmonary disease (COPD). However, their interrelationship, particularly in early COPD, remains unclear. Therefore, we aimed to assess the prevalence and clinical characteristics of MetS in patients with early COPD, and to explore the impact of MetS on the frequency of COPD exacerbations and associated medical costs. Patients and methods: We retrospectively enrolled 43,874 subjects from the KNHANES, including 2164 patients with early COPD (≥40 years old), recorded smoking history, and Global Initiative for Chronic Obstructive Lung Disease spirometric grade I or II, with data linked to the NHI database. We extracted and analyzed data regarding health-care utilization and medical costs for 5 years (2007 to 2012). Results: Among 2164 patients with early COPD, the prevalence of MetS was 31.2%, and it was higher in women than in men (35.1% vs. 26.6%; P<0.001). Patients with MetS were older and had lower pulmonary function and greater number of comorbidities. The frequency of moderate-to-severe COPD exacerbations for 5 years was significantly higher in women with MetS than in those without MetS (5.8/year vs. 4.9/year; P=0.02). After adjusting for confounding factors, the risk for moderate-to-severe exacerbation was significantly greater in women with MetS (IRR, 1.17; 95% CI, 1.01 to 1.36; P=0.03). COPD exacerbations leading to hospitalization and medical expenses were also higher in women with MetS than in those without MetS. Conclusion: MetS is more prevalent in women with early COPD. MetS increased the frequency of exacerbations and the medical costs in women with early COPD.

Improvement of Red Blood Cell Maturation In Vitro by Serum-Free Medium Optimization.

Despite recent studies on media additives, the low viability and dysplastic features of terminally mature erythroid cells are still major problems in enhancing erythroid cell yields in vitro. Moreover, research on enhancing terminal erythropoiesis has been focused on the immature stage of erythroid cells such as burst forming unit-erythroid and colony forming unit-erythroid. Here, we tested many commercially available serum-free culture media and developed a superior culture media formulation compared with the conventional control for higher expansion-fold, higher viability, and therefore enhanced red cell productivity. The addition of the specific medium to the previously known best media at a specific ratio, whose effects were not dose-dependent, enabled the generation of significantly higher erythrocyte products with over 1.3 million-fold proliferation of erythroid cells after maintenance for 21 days throughout the maturation stages from CD34+ cells. The cells cultured in this condition expressed maturation markers and were significantly superior in differentiation and enucleation. Comparative mRNA profiling revealed that erythroid cells in this medium showed more efficient maturation in mRNA levels. The cultured cells showed comparable erythroblast survival and also restored better red blood cell (RBC) functions of oxygen saturation profile with expression of adult globin up to 99%. However, to develop chemically defined media, the well-known supplements including hormones, cytokines, and serum-replacement reagents were not sufficient to replace the optimized media in producing mature RBCs. Taken together, our optimized medium formulation under serum-free culture conditions produced the best reproducible results on productivity and maturation in erythroid cells with economic benefits. These culture conditions may thus serve as a useful platform for further investigation of in vitro erythropoiesis and to develop defined serum-free media for clinical trials.

The effects of plasma gelsolin on human erythroblast maturation for erythrocyte production.

Gelsolin is an actin binding protein present in blood plasma and in cytoplasm of cells including macrophages. Gelsolin has important functions in cell cycle regulation, apoptotic regulation, and morphogenesis. Even though bone marrow macrophages and serum factors are critical for regulating erythropoiesis, the role of gelsolin on human erythroblasts has not been studied. Here, we investigated the effects of human recombinant plasma gelsolin (pGSN) on human immature erythroblasts. CD34+ cells isolated from cord blood were differentiated into erythroid cells in serum-free medium. When pGSN was applied to the culture medium, it accelerated basophilic and polychromatic erythroblast maturation and increased the enucleation rate with highly expressed erythropoiesis-related mRNAs. Also, pGSN was effective in reducing dysplastic changes caused by vincristine, suggesting its role in cell cycle progression at G2/M checkpoints. Also, pGSN activated caspase-3 during maturation stages in which caspase-3 functions as a non-apoptotic maturational signal or a pro-apoptotic signal depending on maturation stages. Our results suggest that pGSN has a pivotal role in maturation of erythroblasts and this factor might be one of the way how bone marrow macrophages and previously unknown serum factors work to control erythropoiesis. pGSN might be used as additive for in vitro production of erythrocytes.

Association of the Neutrophil-to-Lymphocyte Ratio with Lung Function and Exacerbations in Patients with Chronic Obstructive Pulmonary Disease.

BACKGROUND: The ratio of neutrophils to lymphocytes (NLR) is a widely available marker of inflammation. Several types of inflammatory cells and mediators have been found to be involved in the progression of chronic obstructive pulmonary disease (COPD). We sought to evaluate the association of the NLR with severity of airflow limitation and disease exacerbations in a COPD population. METHODS: We analyzed 885 patients from the Korean COPD Subtype Study cohort that recruited subjects with COPD from 44 referral hospitals. We determined the relationship of NLR levels to severity of lung function using a linear regression model. In addition, we analyzed the experiences of COPD exacerbation according to the NLR quartiles. RESULTS: NLR levels were inversely associated with severity of airflow limitation as measured by FEV1% predicted and absolute values after adjustments for age, gender, body mass index, pack-years of smoking, and the use of inhaled corticosteroid (P<0.001, respectively). In the multivariate binary regression model, the NLR 4th quartile (vs. 1st quartile) was found to be a significant predictor of exacerbations during 1-year follow-up (OR = 2.05, 95% CI = 1.03 to 4.06, P = 0.041). Adding an NLR to FEV1 significantly improved prediction for exacerbations during 1-year follow-up as measured by the net reclassification improvement (NRI = 7.8%, P = 0.032) and the integrated discrimination improvement (IDI = 0.014, P = 0.021). CONCLUSIONS: The NLR showed a significant inverse relationship to airflow limitation and was a prognostic marker for future exacerbations in patients with COPD.

Red blood cell generation by three-dimensional aggregate cultivation of late erythroblasts.

Stem cell-derived erythroid cells hold great potential for the treatment of blood-loss anemia and for erythropoiesis research; however, cultures using conventional flat plates or bioreactors have failed to show promising results. By mimicking the in vivo bone marrow (BM) environment in which most erythroid cells are physically aggregated, we show that a three-dimensional (3D) aggregate culture system facilitates erythroid cell maturation and red blood cell (RBC) production more effectively than two-dimensional high-density cell cultivation. Late erythroblasts (polychromatic or orthochromatic erythroblasts) were differentiated from cord blood CD34(+) cells over 15 days and then allowed to form tight aggregates at a minimum density of 1×10(7) cells/mL for 2-3 days. To scale up the cell culture and to make the media supply efficient throughout the cell aggregates, several macroporous microcarriers and porous scaffolds were applied to the 3D culture system. In comparison to control culture conditions, erythroid cells in 3D aggregates were significantly more differentiated toward RBCs with significantly reduced nuclear dysplasia. When 3D culture was performed inside macroporous microcarriers, the cell culture scale was increased and cells exhibited enhanced differentiation and enucleation. Microcarriers with a pore diameter of approximately 400 µm produced more mature cells than those with a smaller pore diameter. In addition, this aggregate culture method minimized the culture space and media volume required. In conclusion, a 3D aggregate culture system can be used to generate transfusable human erythrocytes at the terminal maturation stage, mimicking the in vivo BM microenvironment. Porous structures can efficiently maximize the culture scale, enabling large-scale production of RBCs. These results enhance our understanding of the importance of physical contact among late erythroblasts for their final maturation into RBCs.

Association of lung function genes with chronic obstructive pulmonary disease.

BACKGROUND: Spirometric measurements of pulmonary function are important in diagnosing and determining the severity of chronic obstructive pulmonary disease (COPD). We performed this study to determine whether candidate genes identified in genome-wide association studies of spirometric measurements were associated with COPD and if they interacted with smoking intensity. METHODS: The current analysis included 1,000 COPD subjects and 1,000 controls recruited from 24 hospital-based pulmonary clinics. Thirteen SNPs, chosen based on genome-wide association studies of spirometric measurements in the Korean population cohorts, were genotyped. Genetic association tests were performed, adjusting for age, sex, and smoking intensity, using models including a SNP-by-smoking interaction term. RESULTS: PID1 and FAM13A were significantly associated with COPD susceptibility. There were also significant interactions between SNPs in ACN9 and FAM13A and smoking pack-years, and an association of ACN9 with COPD in the lowest smoking tertile. The risk allele of FAM13A was associated with increased expression of FAM13A in the lung. CONCLUSIONS: We have validated associations of FAM13A and PID1 with COPD. ACN9 showed significant interaction with smoking and is a potential candidate gene for COPD. Significant associations of genetic variants of FAM13A with gene expression levels suggest that the associated loci may act as genetic regulatory elements for FAM13A gene expression.