The correct answer is d. Asbestos exposure is known to cause diffuse and circumscribed pleural thickening the latter synonymous with pleural plaques and interstitial pneumonitis and fibrosis asbestosis. The risk of cancer of the larynx is increased with asbestos exposure but there is no known association of benign vocal cord nodules and asbestos exposure.
Pathophysiology of Emphysema Abbreviations: Goldklang M, Stockley R.
Pathophysiology of emphysema and implications. Chronic Obstr Pulm Dis. There are a multitude of factors that influence disease susceptibility, initiation of injury and progression of disease.
The inhalation of cigarette smoke causes a variety of pro-inflammatory and oxidative stress cascades to be activated within the lung, with resultant protease production and alveolar cell apoptosis, all leading to lung destruction.
This session provided an overview of key aspects of smoke-induced lung injury in order to better understand potential targets for new therapies. Types and Key Questions Lung injury in emphysema is a result of inflammatory and destructive processes in response to cigarette smoke exposure.
In patients with chronic obstructive pulmonary disease COPDpro-inflammatory and pro-destructive pathways are activated, at times independent of smoke exposure, and other anti-inflammatory, anti-oxidant, or repair pathways are down-regulated, all resulting in lung destruction.
It has been long accepted that cigarette smoke leads to airway inflammation, but cigarette smoke also activates epithelial cells to release pro-inflammatory mediators, which amplify inflammation. Under smoke exposure conditions, epithelial cells and recruited inflammatory cells produce proteinases and oxidants that cause lung damage through alveolar septal cell apoptosis and destruction of the extracellular matrix ECM.
Inflammation in Smoke Exposure An increase in inflammatory cells has been documented in the lungs of patients with emphysema. Following smoke exposure, patients have an influx of macrophages and neutrophils into the lung. Neutrophils are implicated not only in disease initiation but also in exacerbations.
As opposed to the human inflammatory response, the mouse experimental model of emphysema has a macrophage predominant inflammatory cell response, with groups demonstrating that mice lacking macrophages do not develop emphysema in smoke exposure conditions.
In addition to macrophages and neutrophils, B cells contribute to COPD development through the generation of lymphoid follicles within the parenchyma of patients with COPD.
The size and number of these follicles is correlated with the severity of COPD. Lung inflammation in COPD is perpetuated by a number of factors that may include latent adenoviral infections, which increase the expression of mediators and adhesion molecules, 4 as well as recurrent bacterial and viral infections, which cause a chronic inflammatory state.
Elastin and collagen fragments cause the release of matrikines that also amplify inflammation within the lung. Main proteinase culprits include neutrophil serine proteinases, matrix metalloproteinases, and cysteine proteinases.
Cigarette smoke induces oxidative stress within the lung as a result of production of reactive oxygen species and reactive nitrogen species and a reduction of antioxidants including glutathione, vitamin A and E, superoxide dismutase and catalase Figure 2.
This oxidant-antioxidant imbalance is a result of reduced NRF2 activity. Oxidative stress has many downstream effects including inflammation, DNA damage and accelerated aging. Oxidative stress also induces epigenetic modifications including the inactivation of of histone deacetylase in continued patients with emphysema.
The inactivation of HDAC2 results in continued pro-inflammatory gene expression and emphysema development. Through programmed cell death apoptosisrecycling of the cell components autophagy or cellular necrosis, there is a loss of alveolar cells and surface area resulting in emphysema.
While well described in epithelial cells, the presence of these processes in the endothelium and leukocytes is not fully described. In summary, lung injury in emphysema results from complex interactions between diverse processes including inflammation, proteinases, oxidative stress and cellular death.
While well described in mice, key cells and culprits in human disease are not as clear. A better understanding of these processes in the human disease is essential to identifying opposing pathways to limit injury and progression.
The host must see cigarette smoke as a danger from the environment in order to initiate inflammatory and oxidative stress responses. The mammalian target of rapamycin mTOR is a sensor molecule that is critically important to the initiation of stress responses in the lung and alveolar maintenance.
Following initiation, the disease progresses through a variety of factors.title = "Lung Basal Stem Cells Rapidly Repair DNA Damage Using the Error-Prone Nonhomologous End-Joining Pathway", abstract = "Lung squamous cell carcinoma (SqCC), the second most common subtype of lung cancer, is strongly associated with tobacco smoking and exhibits genomic instability.
This timeline of lung repair following the cessation of smoking is nothing short of miraculous.
The power and intelligence of the human body is our absolute best hope for longevity, vitality, and wellness. Calcium. Smoking interferes with absorption of calcium, which is essential for building new bones. Decreased calcium absorption, combined with decreased vitamin D absorption and impeded blood circulation, accelerates bone loss, resulting in increased risk of osteoporosis, bone fractures and pain.
However, little is known about the degree to which such cells contribute to resistance to alveolar unit loss under stress, such as with cigarette smoking, or promote pathological mesenchymal expansion during .
agents (ie, quitting smoking) slows the rate of damage; however, unlike the response after acute lung injury, the damaged alveolar structures do not repair and lung func-. Apr 03, · 14 Things That Happen to Your Body When You Quit Smoking (Don’t Avoid) - Duration: Fat Zero , views.