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Current and Future Prospects in the Treatment of Chronic Obstructive Pulmonary Disorders
Published in Suvardhan Kanchi, Rajasekhar Chokkareddy, Mashallah Rezakazemi, Smart Nanodevices for Point-of-Care Applications, 2022
Manu Sharma, Aishwarya Rathore, Sheelu Sharma, Kakarla Raghava Reddy, Veera Sadhu
Lungs are a pair of spongy air-filled organs responsible for gaseous exchange between the blood and inhaled air. The right lung has three lobes and is larger than the left lung which has two lobes. Hence, the right lung holds more air volume. The respiratory tract comprises conducting regions (trachea, bronchi, and bronchioles) and respiratory (peripheral) regions (respiratory bronchioles and alveolar regions) (Figure 7.2). The upper respiratory tract comprises the nose, throat, pharynx, and larynx whereas the trachea, bronchi, bronchioles, and alveolar regions constitute lower respiratory tract. Airways can be simply described by a symmetric model according to which each airway divides into two equivalent branches. The trachea branches into two main bronchi. The right bronchus is wider and leaves the trachea at a smaller angle than the left bronchus and thus is more likely to receive inhaled material. The bronchi branch into terminal bronchioles which further divide to produce respiratory bronchioles. The bronchioles connected to alveolar ducts end in a tiny air sac called alveoli. Alveoli are elastic air sacs that resemble a small balloon where the exchange of gases with blood occurs [3]. Approximately 2 – 6 × 108 alveoli are present in an adult male. The conducting airways are lined by ciliated epithelium cells which facilitate sweeping upward of insoluble particles trapped in mucus deposited on airways by beating cilia and swallowing [4].
Introduction to Anatomy and Physiology
Published in Reginald L. Campbell, Roland E. Langford, Terry L. McArthur, Fundamentals of Hazardous Materials Incidents, 2020
Reginald L. Campbell, Roland E. Langford, Terry L. McArthur
The trachea branches into two major passages called bronchi (singular: bronchus), one going to each lung. These branch in turn into ever smaller passages called bronchioles. All these contain cartilage to prevent collapse. The very smallest bronchioles, however, do not have cartilage rings and simply end in sacs called atria (singular: atrium), each of which contains a number of chambers called alveoli (singular: alveolus). Alveoli are shown in Figure 2-1. It is at the alveoli that the exchange of oxygen to the blood’s hemoglobin and carbon dioxide from the blood takes place. The alveoli on the end of the bronchiole appear like bunches of grapes on a vine. The cells of the alveoli are very sensitive to many chemicals, and the blood lies only one cell thickness away so that transfer of these gases and other substances may occur.
Asbestos Identification and Abatement
Published in Benjamin Alter, Environmental Consulting Fundamentals, 2019
There are three known asbestos-related diseases: asbestosis, lung cancer, and mesothelioma. Asbestosis is a scarring (fibrosis) of the lung that impairs the elasticity of the lung tissue and restricts breathing. Asbestosis has a latency period of 10 to 30 years and generally is associated with a long, heavy exposure to airborne asbestos fibers.Lung cancer is a malignant tumor of the bronchi covering. Although there are many causes of lung cancer, there is a clear increase in risk among people who worked with asbestos. There is no threshold or level of exposure below which the risk of lung cancer is not increased. The typical latency period for lung cancer resulting from asbestos exposure is 20 to 30 years.Mesothelioma is a cancer of the mesothelium—the lining of the chest or the lining of the abdominal wall. It is the only known type of cancer directly attributed to asbestos exposure. By the time it is diagnosed, it is almost always fatal. There is no exposure threshold for mesothelioma, and the disease may not manifest itself until up to 40 years after the time of exposure to asbestos.
The combined effect of ambient ozone exposure and toxic air releases on hospitalization for asthma among children in Harris County, Texas
Published in International Journal of Environmental Health Research, 2018
Nnamdi C. Nnoli, Stephen H. Linder, Mary A. Smith, Gretchen L. Gemeinhardt, Kai Zhang
Asthma is a complex and chronic airway disorder characterized by variable and recurring symptoms, airway inflammation, intermittent airflow obstruction, and bronchial hyperresponsiveness (NHLBI 2007). The disease is characterized by chest tightness, shortness of breath, coughing, and wheezing (Hua et al. 1999). Coughing often occurs at night or early in the morning (NHLBI, 2007). Asthma is associated with significant morbidity, mortality, and health-care use (Akinbami et al. 2012; CDC, 2015). Asthma-related morbidity covers a spectrum from reduced physical activity, absent days at work/school, physician office visits, emergency care, and hospitalization (Paulu and Smith 2008).
Association between greenhouse working exposure and bronchial asthma: A pilot, cross-sectional survey of 5,420 greenhouse farmers from northeast China
Published in Journal of Occupational and Environmental Hygiene, 2019
Shuo Liu, Paul J. Wolters, Yibing Zhang, Mingjing Zhao, Dan Liu, Lingling Wang, Guangdan Zhao, Shitao Mao, Lijian Wu, Hongwen Zhao, Xiaoge Wang
Bronchial asthma, a common chronic airway disorder, is characterized by airway inflammation and bronchial hyper-responsiveness with a prevalence of approximately 5–10% in Western countries.[5–8] There is little information about the prevalence of asthma among the greenhouse farmers. Therefore, we conducted this screening survey to identify the prevalence and the potential risk factors for asthma in greenhouse workers of Liaoning Province in North People’s Republic of China from August 2006 to June 2009.