Progression of Lung Disease

The use of F-labeled analogs of proline has enabled development of a method for monitoring collagen synthesis in vivo (51,52). The uptake of 

The other side of the extracellular matrix balance is the degradation of proteins by matrix metaUoproteinases (MMPs) and their control by specific tissue inhibitors. The fibrosis that results from chronic inflammation is accompanied not only by increase in collagen synthesis but also by increase in the enzymes that control degradation (46). These enzymes are involved in the pathogenesis of tumors, and inhibitors to MMPs have been labeled with F (56) and (57) for oncology imaging with PET. Unfortunately, the localization of markers developed so far in tumors appeared to be related to nonspecific binding (57). 

The activity of MMPs is subject to complex regulation, involving both transcriptional and posttranslational mechanisms. The latter involves a group of endogenous protein inhibitors known as tissue inhibitors of metaUoproteinases (TlMPs), of which there are several. The balance of these enzymes is a major determinant of extracellular matrix control (58). TIMPs have been radiolabeled for imaging studies but have not yet been validated in vivo (59). 

There is a pressing need for validated markers for these processes to advance the development of treatment in various forms of lung fibrosis. At present, few treatments that make any significant impact on these debilitating diseases are available (60,61). 

Increasingly, imaging techniques are playing a major role in the diagnosis and treatment of patients with lung disease. A number of the scans offered routinely in nuclear medicine departments are nonspecific and not fully validated. There is still a considerable gap of knowledge between the clinical usefulness of such scans and the elucidation of mechanisms of disease. 

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High dosages of ibuprofen for 4 years were used in 41 patients with cystic fibrosis to slow progression of lung disease and only two adverse effects (conjunctivitis and epistaxis) were drug-related (SEDA-20, 93). 

The chronic use of antibiotics to suppress bacteria in CF is controversial because antibiotic resistance may be induced or enhanced. Suppressive therapy is prescribed with the intention of prolonging the time between acute exacerbations and to slow the rate of progression of lung disease. Although attractive intuitively, this practice is not supported by well-designed clinical trials. Moreover, the practice of routine, quarterly administration of intravenous courses of antibiotics used at some European centers still lacks proof of efficacy. Aerosolized tobramycin (TOBI) daily for 1 to 2 months has been shown to eradicate P. aeruginosa from the airways of recently infected patients with CF. 

Explain the pathologic progression of lung cancer and its relationship with signs and symptoms of the disease. 

Young We think that the progression of the disease is due largely to the immune response. Eventually their lungs just gum up. The mycobacterial numbers have reached a plateau but there is progressive lung damage by infiltration of T cells. 

A form of lung disease (pneumoconiosis) caused by inhaling fibers of asbestos and marked by interstitial fibrosis of the lung varying in extent from minor involvement of the basal areas to extensive scarring. The disease makes breathing progressively more difficult and can be fatal. 

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