Pleural cavity

Newer bleomycins such as peplomycin and especially liblomycin, are more resistant to bleomycin hydrolase. This results in less lung toxicity but more bone marrow toxicity, and allows for a different spectmm of antitumor action. Bleomycin is inactive orally it is given intravenously, intramuscularly, subcutaneously, or directiy into a cavity such as the pleural cavity. The majority of dmg is excreted unchanged in the urine. 

As a consequence of the inhalation of mineral dusts, infiltration into the lung of inflammatory phagocytic cells, namely PMN and macrophages, occurs (Rola-Pleszczynski et al., 1984). Analysis of the cell populations of the rat pleural cavities after injection with asbestos and silica dust also showed both degranulation and reduction of the mast cell population (Edwards etal., 1984), and it is of interest to note that histamine augments the particle-stimulated generation of macrophage superoxide production (Diaz et al., 1979). 

Once the tumor invades tissues outside the pleural cavity, it can produce a wide array of symptoms, including... 

Involves removal of fluid in the pleural cavity via a needle. The fluid then is assayed for presence cancerous cells. This procedure has low sensitivity and depends on the presence of a pleural effusion... 

Chylothorax The presence of lymphatic fluid (chyle) in the pleural cavity. 

Empyema Pus in the pleural cavity, usually secondary to infection in the lung. 

Pneumothorax The presence of air in the pleural cavity, often causing part of the lung to collapse. 

It appears that activated carbon might be a potential carrier for lymphatic delivery, or to peritoneal or pleural cavities, the most common sites in cancer metastasis. Minimal side effects are expected, since constant low concentrations of drug are maintained in the general circulation. 

Pulmonary pressures. Changes in thoracic volume and lung volume cause pressures within the airways and the pleural cavity to change. These pressure changes create the pressure gradients responsible for airflow in and out of the lungs. Four pressures must be considered (see Figure 17.1) ... 

The entry of air into the pleural cavity is referred to as a pneumothorax. This may occur spontaneously when a "leak" develops on the surface of the lung, allowing air to escape from the airways into pleural space. It may also result from a physical trauma that causes penetration of the chest wall so that air enters pleural space from the atmosphere. In either case, the pleural cavity is no longer a closed space and the pressure within it equilibrates with the atmospheric pressure (0 cmH20). As a result, the transpulmonary pressure is also equal to 0 cmH20 and the lung collapses. 

Five recent studies investigated the potential toxic risk if CNTs reach the pleural cavity after inhalation exposure [6,88-91]. Three of these in vivo studies revealed that if CNTs are delivered to the abdominal cavity of mice or rats, they could induce a serious potential carcinogenic risk resembling that associated with exposure to certain asbestos fibers [6,88,89]. The other two studies described nontoxic responses [90,91]. 

Some workers have reported a failure of NT to elicit significant histamine release (< 5% at 10 /xM NT) from isolated peritoneal mast cells obtained from Wistar strain rats [82]. In these studies, when NT was added to mast cells from the pleural cavity [82] or when the C-terminal octapeptide (NT6 13) or the C-terminal hexapeptide (NT8 13) was added to peritoneal mast cells, a significant (>20% histamine release) secretory response occurred [82]. In our laboratory a significant difference in the responsiveness to NT of peritoneal and pleural mast cells from Sprague-Dawley rats has also been found, pleural cells eliciting a higher percentage of histamine release than peritoneal cells for an equimolar concentration of NT (19.2 2% release for peritoneal mast cells versus 45 + 6% release for pleural mast cells at 10 /xM NT). Moreover, we have also observed anecdotally differences between various populations of mast cells and between various populations of rats in terms of their responsiveness to the same batch of NT. 

Pleural cavity (space between visceral and parietal pleura)... 

Davis, J. M. G. (1972). Pathological effects of mineral dusts injected into the pleural cavity of mice. Br. J. Exper. Pathol. 53 190-201. 

Pleural cavity The potential space between the linings or coverings of the lung and thorax. 

Hueper, WC Experimental studies in metal cancerigenesis. X. Cancerigenic effects of chromite ore roast deposited in muscle tissue and pleural cavity of rats. AMA Arch Ind Health 18 284-291, 1958... 

Bacitracin is highly nephrotoxic when administered systemically and is only used topically (Chapter 62). Bacitracin is poorly absorbed. Topical application results in local antibacterial activity without systemic toxicity. Bacitracin, 500 units/g in an ointment base (often combined with polymyxin or neomycin), is indicated for the suppression of mixed bacterial flora in surface lesions of the skin, in wounds, or on mucous membranes. Solutions of bacitracin containing 100-200 units/mL in saline can be used for irrigation of joints, wounds, or the pleural cavity. 

The L. carinii model is routinely used for primary screening and provides a reliable indication of the in vivo action of a compound. It was first used by Culbertson and Rose [18] for antifilarial screening. This parasitic infection is generally transmitted [ 19-21 ] in 3 weeks by the rat mites Liponsyssus bacoti and requires 8 more weeks to mature in the next animal until microfilariae appear in the blood. The adult filarial worms are found in the pleural cavity. 

Respiratory Maximal breathing capacity reduced, obstructive sleep apnea, fluid accumulation in the pleural cavity... 

K3. Keller, C., Clinical chemistry of the pleural cavity. II. Electrolytes, glucose and bilirubin. Deut. Arch. klin. Med. 201, 539-552 (1954). 

At age 12, the patient was admitted with acute chest pain from a left spontaneous pneumothorax (air within the pleural cavity).This required hospitalization and chest tube insertion, but he recovered without sequelae. After the resolution of this problem, pulmonary function testing revealed findings of both severe airway obstruction and destruction of alveolar lung tissue, consistent with emphysema. No further pulmonary problems occurred until the patient was age 16 years, when he developed occasional episodes of bronchospasm (spasmodic contraction of the smooth muscles of the bronchus). Pulmonary function studies at that time, though improved from those immediately following his pneumothorax, still revealed combined obstructive and destructive lung disease. 

Q5 When air enters the pleural cavity, either from the outside when the chest wall is punctured or from the lung itself if alveoli rupture, the visceral and parietal pleura become separated. The consequence of the introduction of air between the pleura is that the lung does not adhere to the pleura and thoracic wall when thoracic volume increases. Instead, the elastic fibres of the lung tissue and the surface tension of the air-water interface in the alveoli cause lung tissue to recoil and eventually collapse. To reinflate a collapsed lung the hole in the chest wall must be closed, a small tube placed in the pleural cavity and suction applied to remove the air from the cavity. 

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