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1.
Cells ; 11(1)2021 12 22.
Article in English | MEDLINE | ID: covidwho-1580996

ABSTRACT

Patients with COPD may be at an increased risk for severe illness from COVID-19 because of ACE2 upregulation, the entry receptor for SARS-CoV-2. Chronic exposure to cigarette smoke, the main risk factor for COPD, increases pulmonary ACE2. How ACE2 expression is controlled is not known but may involve HuR, an RNA binding protein that increases protein expression by stabilizing mRNA. We hypothesized that HuR would increase ACE2 protein expression. We analyzed scRNA-seq data to profile ELAVL1 expression in distinct respiratory cell populations in COVID-19 and COPD patients. HuR expression and cellular localization was evaluated in COPD lung tissue by multiplex immunohistochemistry and in human lung cells by imaging flow cytometry. The regulation of ACE2 expression was evaluated using siRNA-mediated knockdown of HuR. There is a significant positive correlation between ELAVL1 and ACE2 in COPD cells. HuR cytoplasmic localization is higher in smoker and COPD lung tissue; there were also higher levels of cleaved HuR (CP-1). HuR binds to ACE2 mRNA but knockdown of HuR does not change ACE2 protein levels in primary human lung fibroblasts (HLFs). Our work is the first to investigate the association between ACE2 and HuR. Further investigation is needed to understand the mechanistic underpinning behind the regulation of ACE2 expression.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , COVID-19/genetics , ELAV-Like Protein 1/genetics , Gene Expression Regulation , Lung/metabolism , Aged , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/metabolism , COVID-19/virology , Cells, Cultured , ELAV-Like Protein 1/metabolism , Female , Fibroblasts/metabolism , Gene Expression Profiling/methods , Humans , Lung/pathology , Lung/virology , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/genetics , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/virology , RNA Interference , RNA-Seq/methods , SARS-CoV-2/physiology , Single-Cell Analysis/methods
2.
Dis Markers ; 2021: 6304189, 2021.
Article in English | MEDLINE | ID: covidwho-1553755

ABSTRACT

Background: Early identification of patients with severe coronavirus disease (COVID-19) at an increased risk of progression may promote more individualized treatment schemes and optimize the use of medical resources. This study is aimed at investigating the utility of the C-reactive protein to albumin (CRP/Alb) ratio for early risk stratification of patients. Methods: We retrospectively reviewed 557 patients with COVID-19 with confirmed outcomes (discharged or deceased) admitted to the West Court of Union Hospital, Wuhan, China, between January 29, 2020 and April 8, 2020. Patients with severe COVID-19 (n = 465) were divided into stable (n = 409) and progressive (n = 56) groups according to whether they progressed to critical illness or death during hospitalization. To predict disease progression, the CRP/Alb ratio was evaluated on admission. Results: The levels of new biomarkers, including neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, CRP/Alb ratio, and systemic immune-inflammation index, were higher in patients with progressive disease than in those with stable disease. Correlation analysis showed that the CRP/Alb ratio had the strongest positive correlation with the sequential organ failure assessment score and length of hospital stay in survivors. Multivariate logistic regression analysis showed that percutaneous oxygen saturation (SpO2), D-dimer levels, and the CRP/Alb ratio were risk factors for disease progression. To predict clinical progression, the areas under the receiver operating characteristic curves of Alb, CRP, CRP/Alb ratio, SpO2, and D-dimer were 0.769, 0.838, 0.866, 0.107, and 0.748, respectively. Moreover, patients with a high CRP/Alb ratio (≥1.843) had a markedly higher rate of clinical deterioration (log - rank p < 0.001). A higher CRP/Alb ratio (≥1.843) was also closely associated with higher rates of hospital mortality, ICU admission, invasive mechanical ventilation, and a longer hospital stay. Conclusion: The CRP/Alb ratio can predict the risk of progression to critical disease or death early, providing a promising prognostic biomarker for risk stratification and clinical management of patients with severe COVID-19.


Subject(s)
C-Reactive Protein/metabolism , COVID-19/diagnosis , Coronary Disease/diagnosis , Hypertension/diagnosis , Pulmonary Disease, Chronic Obstructive/diagnosis , SARS-CoV-2/pathogenicity , Serum Albumin, Human/metabolism , Aged , Area Under Curve , Biomarkers/blood , Blood Platelets/pathology , Blood Platelets/virology , COVID-19/epidemiology , COVID-19/mortality , COVID-19/virology , China/epidemiology , Comorbidity , Coronary Disease/epidemiology , Coronary Disease/mortality , Coronary Disease/virology , Disease Progression , Early Diagnosis , Female , Fibrin Fibrinogen Degradation Products/metabolism , Humans , Hypertension/epidemiology , Hypertension/mortality , Hypertension/virology , Length of Stay/statistics & numerical data , Lymphocytes/pathology , Lymphocytes/virology , Male , Middle Aged , Neutrophils/pathology , Neutrophils/virology , Prognosis , Pulmonary Disease, Chronic Obstructive/epidemiology , Pulmonary Disease, Chronic Obstructive/mortality , Pulmonary Disease, Chronic Obstructive/virology , ROC Curve , Retrospective Studies , SARS-CoV-2/growth & development , Severity of Illness Index , Survival Analysis
3.
Am J Infect Control ; 49(2): 238-246, 2021 02.
Article in English | MEDLINE | ID: covidwho-1336188

ABSTRACT

INTRODUCTION: On February 11, 2020 WHO designated the name "COVID-19" for the disease caused by "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2), a novel virus that quickly turned into a global pandemic. Risks associated with acquiring the virus have been found to most significantly vary by age and presence of underlying comorbidity. In this rapid literature review we explore the prevalence of comorbidities and associated adverse outcomes among individuals with COVID-19 and summarize our findings based on information available as of May 15, 2020. METHODS: A comprehensive systematic search was performed on PubMed, Medline, Scopus, Embase, and Google Scholar to find articles published until May 15, 2020. All relevant articles providing information on PCR tested COVID-19 positive patient population with clinical characteristics and epidemiological information were selected for review and analysis. RESULTS: A total of 27 articles consisting of 22,753 patient cases from major epicenters worldwide were included in the study. Major comorbidities seen in overall population were CVD (8.9%), HTN (27.4%), Diabetes (17.4%), COPD (7.5%), Cancer (3.5%), CKD (2.6%), and other (15.5%). Major comorbidity specific to countries included in the study were China (HTN 39.5%), South Korea (CVD 25.6%), Italy (HTN 35.9%), USA (HTN 38.9%), Mexico, (Other 42.3%), UK (HTN 27.8%), Iran (Diabetes 35.0%). Within fatal cases, an estimated 84.1% had presence of one or more comorbidity. Subgroup analysis of fatality association with having comorbidity had an estimated OR 0.83, CI [0.60-0.99], p<0.05. CONCLUSIONS: Based on our findings, hypertension followed by diabetes and cardiovascular diseases were the most common comorbidity seen in COVID-19 positive patients across major epicenters world-wide. Although having one or more comorbidity is linked to increased disease severity, no clear association was found between having these risk factors and increased risk of fatality.


Subject(s)
COVID-19/epidemiology , Comorbidity , Global Health/statistics & numerical data , Hypertension/epidemiology , SARS-CoV-2 , Adult , Aged , Aged, 80 and over , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/virology , Diabetes Mellitus/epidemiology , Diabetes Mellitus/virology , Female , Humans , Hypertension/virology , Male , Middle Aged , Neoplasms/epidemiology , Neoplasms/virology , Prevalence , Pulmonary Disease, Chronic Obstructive/epidemiology , Pulmonary Disease, Chronic Obstructive/virology , Renal Insufficiency, Chronic/epidemiology , Renal Insufficiency, Chronic/virology , Young Adult
4.
STAR Protoc ; 2(3): 100663, 2021 09 17.
Article in English | MEDLINE | ID: covidwho-1275773

ABSTRACT

Patients with chronic lung disease are vulnerable to getting severe diseases associated with SARS-CoV-2 infection. Here, we describe protocols for subculturing and differentiating primary normal human bronchial epithelial (NHBE) cells of patients with chronic obstructive lung disease. The differentiation of NHBE cells in air-liquid interface mimics an in vivo airway and provides an in vitro model for studying SARS-CoV-2 infection. We also describe a protocol for detecting proteins in the sectioned epithelium for detailing SARS-CoV-2 infection-induced pathobiology with a vertical view.


Subject(s)
Bronchi/metabolism , COVID-19/complications , Coronavirus Nucleocapsid Proteins/analysis , Epithelium/metabolism , Pulmonary Disease, Chronic Obstructive/pathology , SARS-CoV-2/isolation & purification , Bronchi/pathology , Bronchi/virology , COVID-19/metabolism , COVID-19/virology , Coronavirus Nucleocapsid Proteins/metabolism , Epithelium/pathology , Epithelium/virology , Humans , Immunohistochemistry , Paraffin Embedding , Phosphoproteins/analysis , Phosphoproteins/metabolism , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/virology , Virus Replication
5.
J Pathol Clin Res ; 7(5): 446-458, 2021 09.
Article in English | MEDLINE | ID: covidwho-1224964

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a serious threat to healthcare systems worldwide. Binding of the virus to angiotensin-converting enzyme 2 (ACE2) is an important step in the infection mechanism. However, it is unknown if ACE2 expression in patients with chronic lung diseases (CLDs), such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary arterial hypertension (IPAH), or pulmonary fibrosis (PF), is changed as compared to controls. We used lung samples from patients with COPD (n = 28), IPAH (n = 10), and PF (n = 10) as well as healthy control donor (n = 10) tissue samples to investigate the expression of ACE2 and related cofactors that might influence the course of SARS-CoV-2 infection. Expression levels of the ACE2 receptor, the putative receptor CD147/BSG, and the viral entry cofactors TMPRSS2 (transmembrane serine protease 2), EZR, and FURIN were determined by quantitative PCR and in open-access RNA sequencing datasets. Immunohistochemical and single-cell RNA sequencing (scRNAseq) analyses were used for localization and coexpression, respectively. Soluble ACE2 (sACE2) plasma levels were analyzed by enzyme-linked immunosorbent assay. In COPD as compared to donor, IPAH, and PF lung tissue, gene expression of ACE2, TMPRSS2, and EZR was significantly elevated, but circulating sACE2 levels were significantly reduced in COPD and PF plasma compared to healthy control and IPAH plasma samples. Lung tissue expressions of FURIN and CD147/BSG were downregulated in COPD. None of these changes were associated with changes in pulmonary hemodynamics. Histological analysis revealed coexpression of ACE2, TMPRSS2, and Ezrin in bronchial regions and epithelial cells. This was confirmed by scRNAseq analysis. There were no significant expression changes of the analyzed molecules in the lung tissue of IPAH and idiopathic PF as compared to control. In conclusion, we reveal increased ACE2 and TMPRSS2 expression in lung tissue with a concomitant decrease of protective sACE2 in COPD patients. These changes represent the possible risk factors for an increased susceptibility of COPD patients to SARS-CoV-2 infection.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/pathology , Familial Primary Pulmonary Hypertension/pathology , Idiopathic Pulmonary Fibrosis/pathology , Pulmonary Disease, Chronic Obstructive/pathology , SARS-CoV-2/physiology , Serine Endopeptidases/metabolism , Adult , Aged , Angiotensin-Converting Enzyme 2/genetics , Basigin/genetics , Basigin/metabolism , COVID-19/metabolism , COVID-19/virology , Disease Susceptibility , Familial Primary Pulmonary Hypertension/enzymology , Familial Primary Pulmonary Hypertension/virology , Female , Furin/genetics , Furin/metabolism , Gene Expression Regulation , Humans , Idiopathic Pulmonary Fibrosis/metabolism , Idiopathic Pulmonary Fibrosis/virology , Lung/metabolism , Lung/pathology , Lung/virology , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/virology , Risk Factors , Serine Endopeptidases/genetics , Virus Internalization
6.
Comput Biol Med ; 128: 104126, 2021 01.
Article in English | MEDLINE | ID: covidwho-996804

ABSTRACT

Genes act in groups known as gene modules, which accomplish different cellular functions in the body. The modular nature of gene networks was used in this study to detect functionally enriched modules in samples obtained from COPD patients. We analyzed modules extracted from COPD samples and identified crucial genes associated with the disease COVID-19. We also extracted modules from a COVID-19 dataset and analyzed a suspected set of genes that may be associated with this deadly disease. We used information available for two other viruses that cause SARS and MERS because their physiology is similar to that of the COVID-19 virus. We report several crucial genes associated with COVID-19: RPA2, POLD4, MAPK8, IRF7, JUN, NFKB1, NFKBIA, CD40LG, FASLG, ICAM1, LIFR, STAT2 and CCR1. Most of these genes are related to the immune system and respiratory organs, which emphasizes the fact that COPD weakens this system and makes patients more susceptible to developing severe COVID-19.


Subject(s)
COVID-19/genetics , Databases, Nucleic Acid , Genetic Predisposition to Disease , Pulmonary Disease, Chronic Obstructive/genetics , SARS-CoV-2/genetics , COVID-19/immunology , Humans , Pulmonary Disease, Chronic Obstructive/immunology , Pulmonary Disease, Chronic Obstructive/virology , SARS-CoV-2/immunology , Severity of Illness Index
7.
Biofactors ; 47(1): 6-18, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-950385

ABSTRACT

Specialized proresolving mediators (SPMs) are endogenous lipid metabolites of long-chain polyunsaturated fatty acids that are involved in promoting the resolution of inflammation. Many disease conditions characterized by excessive inflammation have impaired or altered SPM biosynthesis, which may lead to chronic, unresolved inflammation. Exogenous administration of SPMs in infectious conditions has been shown to be effective at improving infection clearance and survival in preclinical models. SPMs have also shown tremendous promise in the context of inflammatory lung conditions, such as acute respiratory distress syndrome and chronic obstructive pulmonary disease, mostly in preclinical settings. To date, SPMs have not been studied in the context of the novel Coronavirus, severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), however their preclinical efficacy in combatting infections and improving acute respiratory distress suggest they may be a valuable resource in the fight against Coronavirus disease-19 (COVID-19). Overall, while the research on SPMs is still evolving, they may offer a novel therapeutic option for inflammatory conditions.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , COVID-19/drug therapy , Docosahexaenoic Acids/therapeutic use , Lipoxins/therapeutic use , Lung Injury/drug therapy , Pulmonary Disease, Chronic Obstructive/drug therapy , Respiratory Distress Syndrome/drug therapy , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , Herpes Simplex/drug therapy , Herpes Simplex/metabolism , Herpes Simplex/pathology , Humans , Influenza, Human/drug therapy , Influenza, Human/metabolism , Influenza, Human/pathology , Lung/drug effects , Lung/metabolism , Lung/pathology , Lung Injury/metabolism , Lung Injury/pathology , Lung Injury/virology , Periodontitis/drug therapy , Periodontitis/metabolism , Periodontitis/pathology , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/pathology , Pulmonary Disease, Chronic Obstructive/virology , Respiratory Distress Syndrome/metabolism , Respiratory Distress Syndrome/pathology , Respiratory Distress Syndrome/virology , SARS-CoV-2/pathogenicity , Sepsis/drug therapy , Sepsis/metabolism , Sepsis/pathology , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/metabolism , Tuberculosis, Pulmonary/pathology
8.
Diabetes Res Clin Pract ; 169: 108454, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-778739

ABSTRACT

AIMS: To evaluate whether subjects with diabetes hospitalized for Coronavirus disease-19 (Covid-19) represent a subgroup of patients with high-risk clinical features compared to patients with diabetes without Covid-19. METHODS: In this case-control study 79 patients with type 2 diabetes out of 354 adults hospitalized for Covid-19 and 158 controls with type 2 diabetes but without Covid-19, matched for age and gender, were enrolled. Medical history and concomitant therapies were retrieved from medical charts and compared between cases and controls, controlling for confounders. RESULTS: Fully-adjusted multivariate logistic regression model showed that previous CVD history did not differ between patients with and without Covid-19 (odds ratio 1.40, 95% confidence interval [CI]: 0.59-3.32, p = 0.45). A higher prevalence of chronic obstructive pulmonary disease (COPD) (OR 3.72, 95%CI: 1.42-9.72, p = 0.007) and of chronic kidney disease (CKD) (OR 3.08, 95%CI: 1.18-8.06, p = 0.022) and a lower prevalence of ever smokers (OR 0.30, 95%CI: 0.13-0.67, p = 0.003), of users of lipid lowering agents (OR 0.26, 95%CI: 0.12-0.54, p < 0.001), and of anti-hypertensive drugs (OR 0.39, 95%CI: 0.16-0.93, p = 0.033) were found among cases. CONCLUSIONS: CVD prevalence does not differ between people with diabetes with and without Covid-19 requiring hospitalization. An increased prevalence of COPD and of CKD in Covid-19 patients with type 2 diabetes is suggested. These findings aid to clarify the relationship between underlying conditions and SARS-CoV-2 infection in the high-risk group of patients with diabetes.


Subject(s)
COVID-19/complications , Diabetes Mellitus, Type 2/pathology , Pulmonary Disease, Chronic Obstructive/pathology , Renal Insufficiency, Chronic/pathology , SARS-CoV-2/isolation & purification , Aged , Aged, 80 and over , COVID-19/transmission , COVID-19/virology , Case-Control Studies , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/virology , Female , Hospitalization , Humans , Incidence , Italy/epidemiology , Male , Pulmonary Disease, Chronic Obstructive/epidemiology , Pulmonary Disease, Chronic Obstructive/virology , Renal Insufficiency, Chronic/epidemiology , Renal Insufficiency, Chronic/virology
9.
J Allergy Clin Immunol ; 146(4): 808-812, 2020 10.
Article in English | MEDLINE | ID: covidwho-680229
10.
Med Hypotheses ; 144: 110133, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-670653

ABSTRACT

COVID-19 is an overwhelming pandemic which has shattered the whole world. Lung injury being the main clinical manifestation, it is likely to cause COPD (chronic obstructive pulmonary disease) and ARDS (acute respiratory distress syndrome). The possible cause behind this might be redox imbalance due to viral infection. Elevation in Glutathione (GSH) levels by administration of its promolecule might be effective. N-acetylcysteine is one such drug with potency to scavenge Reactive Oxygen Species, least side effects, and an effective precursor of glutathione. Consequently we hypothesize that N-acetylcysteine along with the conventional treatment may be treated as a potential therapeutic solution in cases of COVID-19 patients.


Subject(s)
Acetylcysteine/therapeutic use , COVID-19/drug therapy , Glutathione/metabolism , Acetylcysteine/chemistry , Antioxidants/therapeutic use , Humans , Oxidation-Reduction , Oxidative Stress , Pulmonary Disease, Chronic Obstructive/virology , Reactive Oxygen Species/metabolism , Respiratory Distress Syndrome/drug therapy , Respiratory Distress Syndrome/virology
11.
Res Social Adm Pharm ; 17(1): 1934-1937, 2021 01.
Article in English | MEDLINE | ID: covidwho-459548

ABSTRACT

Chronic Obstructive Pulmonary Disease (COPD) is a chronic inflammation in the lungs that causes obstruction in the airway, poor airflow, and irreversible loss of lung function. In clinical practice, comprehensive care for COPD patients includes the diagnosis using spirometry, clinical examination and comprehensive pharmacological and non-pharmacological management. The diagnosis is based on symptoms, dyspnea and lung function impairment and can be mild to very severe. Symptoms are examined using the COPD assessment test (CAT) score, and dyspnea grade are examined using a modified MRC from GOLD guidelines. When mild, the care includes self-management education, smoking cessation, lifestyle modifications, vaccination, and short-acting bronchodilators. Self-management education involves inhaler device training, breathing technique, early recognition of acute exacerbations and writing action plans. As the disease progresses, other care measures are added. These measures include the addition of long-acting inhaler therapies, pulmonary rehabilitation, oral therapies, oxygen and lung transplantation. During the final stages of COPD, patients receive end-of-life care (Bourbeau et al., 2019).1 The novel coronavirus disease (COVID-19) is a viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that is spread through respiratory droplets. This infectious disease has led to a pandemic and is affecting the lives of many around the world, including Canadians. During this pandemic, the non-essential health services, including caring for patients with COPD, have been put on hold to reduce the risk of spread. Other implications of this pandemic for COPD patients include the health risk in case of infection. A meta-analysis including studies from January to March 2020 in Wuhan showed that pre-existing COPD worsens the risk of COVID-19 progression and leads to poorer prognostics. The sub-group analysis showed a significantly higher risk of ICU requirements and death in COPD patients who are infected with the SARS-CoV-2 virus. Studies suggest strong efforts to mitigate the risk of infection in this population (Zhao et al., May 2020).2 This makes caring for this population even more critical during the pandemic.


Subject(s)
COVID-19/complications , Health Services Accessibility , Pulmonary Disease, Chronic Obstructive/therapy , Canada , Disease Progression , Humans , Intensive Care Units/statistics & numerical data , Prognosis , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Disease, Chronic Obstructive/virology
13.
Respir Res ; 21(1): 77, 2020 Mar 30.
Article in English | MEDLINE | ID: covidwho-19745

ABSTRACT

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by frequent exacerbation phenotypes independent of disease stage. Increasing evidence shows that the microbiota plays a role in disease progression and severity, but long-term and international multicenter assessment of the variations in viral and bacterial communities as drivers of exacerbations are lacking. METHODS: Two-hundred severe COPD patients from Europe and North America were followed longitudinally for 3 years. We performed nucleic acid detection for 20 respiratory viruses and 16S ribosomal RNA gene sequencing to evaluate the bacterial microbiota in 1179 sputum samples collected at stable, acute exacerbation and follow-up visits. RESULTS: Similar viral and bacterial taxa were found in patients from the USA compared to Bulgaria and Czech Republic but their microbiome diversity was significantly different (P < 0.001) and did not impact exacerbation rates. Virus infection was strongly associated with exacerbation events (P < 5E-20). Human rhinovirus (13.1%), coronavirus (5.1%) and influenza virus (3.6%) constitute the top viral pathogens in triggering exacerbation. Moraxella and Haemophilus were 5-fold and 1.6-fold more likely to be the dominating microbiota during an exacerbation event. Presence of Proteobacteria such as Pseudomonas or Staphylococcus amongst others, were associated with exacerbation events (OR > 0.17; P < 0.02) but more strongly associated with exacerbation frequency (OR > 0.39; P < 4E-10), as confirmed by longitudinal variations and biotyping of the bacterial microbiota, and suggesting a role of the microbiota in sensitizing the lung. CONCLUSIONS: This study highlights bacterial taxa in lung sensitization and viral triggers in COPD exacerbations. It provides a global overview of the diverse targets for drug development and explores new microbiome analysis methods to guide future patient management applications.


Subject(s)
Bacteria/isolation & purification , Lung/microbiology , Lung/virology , Pulmonary Disease, Chronic Obstructive/microbiology , Pulmonary Disease, Chronic Obstructive/virology , Viruses/isolation & purification , Aged , Aged, 80 and over , Bacteria/genetics , Bacterial Load , Disease Progression , Europe/epidemiology , Female , Humans , Incidence , Longitudinal Studies , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/epidemiology , Retrospective Studies , Risk Factors , Sputum/microbiology , Sputum/virology , Time Factors , United States/epidemiology , Viral Load , Viruses/genetics
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