In a healthy human, the airway mucus forms a thin, protective liquid layer covering the surface of the respiratory tract. It comprises a complex blend of mucin, multiple antibacterial proteins, metabolic substances, water, and electrolytes. This mucus plays a pivotal role in the lungs' innate immune system by maintaining airway hydration and capturing airborne particles and pathogens. However, heightened mucus secretion in the airway can compromise ciliary clearance, obstruct the respiratory tract, and increase the risk of pathogen colonization and recurrent infections. Consequently, a thorough exploration of the mechanisms driving excessive airway mucus secretion is crucial for establishing a theoretical foundation for the eventual development of targeted drugs designed to reduce mucus production. Across a range of lung diseases, excessive airway mucus secretion manifests with unique characteristics and regulatory mechanisms, all intricately linked to mucin. This article provides a comprehensive overview of the characteristics and regulatory mechanisms associated with excessive airway mucus secretion in several prevalent lung diseases.
Humans ; Mucus/metabolism* ; Mucins/physiology* ; Lung Diseases/metabolism* ; Respiratory Mucosa/metabolism* ; Pulmonary Disease, Chronic Obstructive/physiopathology* ; Asthma/physiopathology* ; Cystic Fibrosis/physiopathology* ; Mucociliary Clearance/physiology*

Electrical impedance tomography (EIT) is a new non-invasive functional imaging technology, which has the advantages of non-invasion, non-radiation, low cost, fast response, portability and visualization. In recent years, more and more studies have shown that EIT has great potential in the detection of lung diseases and has been applied to early diagnosis and treatment of some diseases. This paper introduced the basic principle of EIT, discussed the research and clinical application of EIT in the detection of acute respiratory distress syndrome, chronic obstructive pulmonary disease, pneumothorax and pulmonary embolism, and focused on the summary and introduction of indicators and functional images of EIT related to the detection of lung diseases. This review will help medical workers understand and use EIT, and promote the further development of EIT in lung diseases as well as other fields.
Humans ; Electric Impedance ; Tomography/methods* ; Lung Diseases/diagnosis* ; Pulmonary Disease, Chronic Obstructive/diagnosis* ; Pulmonary Embolism/diagnosis* ; Respiratory Distress Syndrome/diagnosis*

Objectives To investigate interleukin 36γ (IL-36γ) expression, and analyze the influence of IL-36γ to CD8⁺ T cell activity in chronic obstructive pulmonary diseases (COPD) patients with secondary fungal pneumonia. Methods Peripheral blood was collected from 47 COPD patients, 39 COPD patients with secondary fungal pneumonia, and 20 controls. Bronchial alveolar lavage fluid (BALF) was isolated from 27 COPD patients with secondary fungal pneumonia. CD8⁺ T cells were purified. The levels of four IL-36 isoforms in plasma and BALF were measured by enzyme linked immunosorbent assay (ELISA). CD8⁺ T cells were stimulated with recombinant human IL-36γ. The levels of interferon γ(IFN-γ), tumor necrosis factor α(TNF-α), perforin and granzyme B in the cultured supernatants were measured by ELISA. Recombinant human IL-36γ-stimulated CD8⁺ T cells were co-cultured with NCI-H1882 cells in either direct cell-to-cell contact or Transwell^TM manner. The levels of IFN-γ, TNF-α, and lactate dehydrogenase in the cultured supernatants were assessed. The percentage of target cell death was calculated. Results Plasma IL-36α, IL-36β, and IL-36γ levels were significantly elevated in both COPD group and COPD with secondary fungal pneumonia group compared with those in control group. However, only plasma IL-36γ level was higher in COPD with secondary fungal pneumonia group than that in COPD group [(200.11±99.95)pg/mL vs (53.03±87.18)pg/mL, P=0.023]. There was no remarkable difference in plasma IL-36 receptor antagonist level among three groups. IL-36γ level in BALF from infectious site was higher than that from non-infectious site in COPD with secondary fungal pneumonia group [(305.82±59.60)pg/mL vs (251.93±76.01)pg/mL, P=0.011]. IL-36γ stimulation enhanced IFN-γ, TNF-α, perforin and granzyme B secreted by CD8⁺ T cells. When IL-36γ-stimulated CD8⁺ T cells were directly mixed with NCI-H1882 cells for co-culture, the percentage of cell death was increased [(16.06±3.67)% vs (11.47±2.36)%, P=0.002]. When using Transwell^TM plate for non-contact co-culture, IL-36γ-stimulated CD8⁺ T cell-mediated death of NCI-H1882 cells showed no significant difference compared to that without stimulation [(4.77±0.78)% vs (4.99±0.92)%, P=0.554]. Conclusion IL-36γ level in plasma and infectious site is elevated in COPD patients with secondary fungal pneumonia, which enhances the cytotoxicity of CD8⁺ T cells in peripheral blood and infectious microenviroment.
Humans ; Pulmonary Disease, Chronic Obstructive/complications* ; CD8-Positive T-Lymphocytes/metabolism* ; Male ; Female ; Aged ; Middle Aged ; Interferon-gamma/metabolism* ; Interleukin-1/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Lung Diseases, Fungal/complications* ; Bronchoalveolar Lavage Fluid/chemistry* ; Perforin/metabolism* ; Pneumonia/immunology* ; Granzymes/metabolism*

PANoptosis is a newly defined type of programmed cell death (PCD), which is triggered by a variety of stimuli and covers three known forms of PCD: apoptosis, pyroptosis and necroptosis. In physiological state, cell death plays an important protective role against pathogen invasion, but its over-activation may aggravate inflammatory response and cause tissue damage. Studies have shown that the occurrence and progression of acute lung injury/acute respiratory distress syndrome (ALI/ARDS), asthma, chronic obstructive pulmonary disease (COPD) and other lung diseases are closely related to PANoptosis. The purpose of this review is to deeply explore the molecular mechanism of PANoptosis and its regulatory factors in lung diseases, in order to discover potential therapeutic targets and provide new targets and innovative ideas for clinical treatment for lung diseases.
Humans ; Lung Diseases ; Apoptosis ; Pyroptosis ; Pulmonary Disease, Chronic Obstructive ; Necroptosis ; Acute Lung Injury

Humans ; Aged ; Lung Diseases ; Pneumonia/drug therapy* ; Adrenal Cortex Hormones/therapeutic use* ; Pulmonary Disease, Chronic Obstructive/drug therapy* ; Administration, Inhalation ; Community-Acquired Infections/drug therapy*

Objective: To analyze the case characteristics of Chronic obstructive pulmonary disease caused by occupational irritant chemicals (OI-COPD). To provide basis for revising its diagnostic criteria. Methods: From June to December 2021, we investigated the information of OI-COPD patients confirmed by Shandong Institute of Occupational Health and Prevention of Occupational Diseases, Guangxi Zhuang Autonomous Region Institute of Occupational Disease Prevention and Control, Qingdao Central Hospital affiliated to Qingdao University and other diagnostic institutions in the past five years, a total of 41 cases. The basic information of OI-COPD cases, occupational risk factors exposure information, medical history, smoking history and clinical symptoms were analyzed retrospectively. The measurement data were tested for normal distribution, which was described by x±s, and compared between groups by t test; Those who do not conform to the normal distribution are described by the median [M (Q(1), Q(3)) ] and analyzed by nonparametric test; The counting data were expressed in frequency and rate (% ), and the comparison between groups was tested. Results: Of the 41 cases, 33 were male and 8 were female. The age of the patient diagnosed with OI-COPD was (49.5±10.3) years old, and the minimum age was 30 years old; Among them, 8 patients had a definite long-term smoking history (more than 5 years) ; The exposure duration of occupational risk factors was (18.6±10.3) years, of which 3 patients had exposure duration of less than 5 years; The occupational risk factors leading to OI-COPD include acids and acid-forming compounds, bases, aldehydes, nitrogen oxides, chlorine and its compounds, etc. The exposure level of occupational risk factors is related to the degree of COPD airflow restriction (χ(2)=6.17, P <0.05). 18 patients with diagnosis age <50 years old were diagnosed as early-onset COPD. The incidence of respiratory symptoms in the early diagnosis COPD group was lower than that in the non-early diagnosis COPD group, and the FEV1% pred was significantly higher than that in the non-early diagnosis COPD group. The difference was statistically significant (P<0.01 ) . Conclusion: The exposure level of occupational risk factors may be the risk factor affecting the degree of COPD airflow restriction. With the increase of the exposure level of COPD patients, the proportion of respiratory symptoms will also increase accordingly.
Humans ; Male ; Female ; Adult ; Middle Aged ; Retrospective Studies ; China/epidemiology* ; Pulmonary Disease, Chronic Obstructive/diagnosis* ; Lung ; Risk Factors ; Occupational Diseases/diagnosis* ; Occupational Exposure/adverse effects*

Mucociliary clearance system is the primary innate defense mechanism of the lung. It plays a vital role in protecting airways from microbes and irritants infection. Mucociliary clearance system, which is mediated by the actions of airway and submucosal gland epithelial cells, plays a critical role in a multilayered defense system via secreting fluids, electrolytes, antimicrobial and anti-inflammatory proteins, and mucus onto airway surfaces. Changes in environment, drugs or diseases can lead to mucus overproduction and cilia dysfunction, which in turn decrease the rate of mucociliary clearance and enhance mucus gathering. The dysfunction of mucociliary clearance system often occurs in several respiratory diseases, such as primary ciliary dysfunction, cystic fibrosis, asthma and chronic obstructive pulmonary disease, which are characterized by goblet cell metaplasia, submucosal gland cell hypertrophy, mucus hypersecretion, cilia adhesion, lodging and loss, and airway obstruction.
Humans ; Mucociliary Clearance ; Respiratory Tract Diseases ; Pulmonary Disease, Chronic Obstructive/metabolism* ; Mucus/metabolism* ; Lung ; Respiratory System

Objective: To investigate the chronic respiratory symptoms and pulmonary function of adult residents in 3 towns of Hongtong County, Shanxi Province, and to explore their risk factors. Methods: The investigation of chronic respiratory symptoms and lung function status of adult residents in Hongdong County is based on the regional population of the entire county in Hongdong County. The project was initiated by the Science and Technology Department of Linfen City and coordinated by the Hongdong County Government. The investigation will be conducted in 3 townships in Hongdong County, Linfen City, Shanxi Province from April to November 2021: Demographic characteristics, respiratory symptoms, smoking dust exposure and other personal history were collected through questionnaires. Physical examination, routine blood tests and lung function tests were also performed on each individual. SPSS 22.0 software was used to conduct t test, χ² test, ANOVA or Kruskal-Wallis test for statistical analysis of the collected information. Results: 10 945 subjects aged 18-102 years were included in the analysis, of whom 3 754 (34.3%) were male, 1 222 (11.2%) had a history of dust exposure, 7 164 (65.5%) had used straw and firewood as cooking fuel, and 3 296 (30.1%) had a history of smoking. Among the participants, 394 (3.6%), 339 (3.1%), and 1 543 (14.1%) had respiratory symptoms such as chronic cough, sputum, and dyspnea. Statistics showed that the population with chronic respiratory symptoms was more elderly and had a smoking history, and the incidence of chronic respiratory symptoms was higher in those who smoked more than 40 packs a year (all P<0.05). Men with a history of dust exposure were more likely to suffer from chronic cough and expectoration, while emaciation and biofuel use for more than 40 years were more likely to suffer from chronic expectoration and dyspnea (all P<0.05). The median values of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and FEV1/FVC in 1 second were 2.19 L/s, 3.24 L and 69.16%, respectively. Among them, the lung function of 5 801 (53.0%) respondents was lower than the expected value. The median FEV1/FVC decreased with the increase of age. The FEV1/FVC of people over 40 years old with smoking history was lower, the dust exposure history of people with decreased lung function was more than that of people with normal lung function, and the incidence of chronic expectoration and dyspnea was higher in people with decreased lung function (all P<0.05). The absolute value and ratio of eosinophils in patients with decreased ventilation function over 60 years old were significantly higher than those with normal ventilation function, but the level of body mass index (BMI) was lower (all P<0.05). Conclusion: In Hongdong County, Shanxi Province, grassroots residents have poor medical awareness, low lung function examination rate, chronic respiratory symptoms and lung function decline are associated with more risk factors. Primary medical institutions need to formulate prevention strategies and carry out lung function detection according to the actual situation, focusing on monitoring and follow-up of high-risk groups to achieve early and timely prevention, diagnosis and treatment of chronic obstructive pulmonary disease.
Aged ; Adult ; Humans ; Male ; Middle Aged ; Female ; Cough/epidemiology* ; Lung ; Pulmonary Disease, Chronic Obstructive/epidemiology* ; Chronic Disease ; Lung Diseases ; Vital Capacity ; Dyspnea ; Dust/analysis* ; Forced Expiratory Volume

Objective: To investigate the chronic respiratory symptoms and pulmonary function of adult residents in 3 towns of Hongtong County, Shanxi Province, and to explore their risk factors. Methods: The investigation of chronic respiratory symptoms and lung function status of adult residents in Hongdong County is based on the regional population of the entire county in Hongdong County. The project was initiated by the Science and Technology Department of Linfen City and coordinated by the Hongdong County Government. The investigation will be conducted in 3 townships in Hongdong County, Linfen City, Shanxi Province from April to November 2021: Demographic characteristics, respiratory symptoms, smoking dust exposure and other personal history were collected through questionnaires. Physical examination, routine blood tests and lung function tests were also performed on each individual. SPSS 22.0 software was used to conduct t test, χ² test, ANOVA or Kruskal-Wallis test for statistical analysis of the collected information. Results: 10 945 subjects aged 18-102 years were included in the analysis, of whom 3 754 (34.3%) were male, 1 222 (11.2%) had a history of dust exposure, 7 164 (65.5%) had used straw and firewood as cooking fuel, and 3 296 (30.1%) had a history of smoking. Among the participants, 394 (3.6%), 339 (3.1%), and 1 543 (14.1%) had respiratory symptoms such as chronic cough, sputum, and dyspnea. Statistics showed that the population with chronic respiratory symptoms was more elderly and had a smoking history, and the incidence of chronic respiratory symptoms was higher in those who smoked more than 40 packs a year (all P<0.05). Men with a history of dust exposure were more likely to suffer from chronic cough and expectoration, while emaciation and biofuel use for more than 40 years were more likely to suffer from chronic expectoration and dyspnea (all P<0.05). The median values of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and FEV1/FVC in 1 second were 2.19 L/s, 3.24 L and 69.16%, respectively. Among them, the lung function of 5 801 (53.0%) respondents was lower than the expected value. The median FEV1/FVC decreased with the increase of age. The FEV1/FVC of people over 40 years old with smoking history was lower, the dust exposure history of people with decreased lung function was more than that of people with normal lung function, and the incidence of chronic expectoration and dyspnea was higher in people with decreased lung function (all P<0.05). The absolute value and ratio of eosinophils in patients with decreased ventilation function over 60 years old were significantly higher than those with normal ventilation function, but the level of body mass index (BMI) was lower (all P<0.05). Conclusion: In Hongdong County, Shanxi Province, grassroots residents have poor medical awareness, low lung function examination rate, chronic respiratory symptoms and lung function decline are associated with more risk factors. Primary medical institutions need to formulate prevention strategies and carry out lung function detection according to the actual situation, focusing on monitoring and follow-up of high-risk groups to achieve early and timely prevention, diagnosis and treatment of chronic obstructive pulmonary disease.
Aged ; Adult ; Humans ; Male ; Middle Aged ; Female ; Cough/epidemiology* ; Lung ; Pulmonary Disease, Chronic Obstructive/epidemiology* ; Chronic Disease ; Lung Diseases ; Vital Capacity ; Dyspnea ; Dust/analysis* ; Forced Expiratory Volume

Molecular hydrogen exerts biological effects on nearly all organs. It has anti-oxidative, anti-inflammatory, and anti-aging effects and contributes to the regulation of autophagy and cell death. As the primary organ for gas exchange, the lungs are constantly exposed to various harmful environmental irritants. Short- or long-term exposure to these harmful substances often results in lung injury, causing respiratory and lung diseases. Acute and chronic respiratory diseases have high rates of morbidity and mortality and have become a major public health concern worldwide. For example, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. An increasing number of studies have revealed that hydrogen may protect the lungs from diverse diseases, including acute lung injury, chronic obstructive pulmonary disease, asthma, lung cancer, pulmonary arterial hypertension, and pulmonary fibrosis. In this review, we highlight the multiple functions of hydrogen and the mechanisms underlying its protective effects in various lung diseases, with a focus on its roles in disease pathogenesis and clinical significance.
Acute Lung Injury ; Aging ; Animals ; Anti-Inflammatory Agents ; Antioxidants/chemistry* ; Asthma/therapy* ; Autophagy ; COVID-19/therapy* ; Humans ; Hydrogen/therapeutic use* ; Hypertension, Pulmonary/therapy* ; Inflammation ; Lung Diseases/therapy* ; Lung Neoplasms/therapy* ; Mice ; Oxidative Stress ; Pulmonary Disease, Chronic Obstructive/therapy* ; Pulmonary Fibrosis/therapy* ; Pyroptosis ; Reactive Oxygen Species