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Background: We have recently shown that transforming growth factor (TGF)beta(2) induces effective pleurodesis in rabbits. However, rabbits have a thin pleura while humans have a thick visceral pleura. The effect of intrapleural administration of TGF beta(2) in animals with a thick pleura and its associated systemic effects have not been investigated. This study was undertaken (1) to develop a new animal model for the study of pleurodesis using sheep which have a thick pleura resembling that of humans; (2) to study the efficacy of TGF beta(2) as a pleurodesis agent in the sheep model; and (3) to assess whether histological changes occur in extrapulmonary organs after intrapleural administration of TGF beta(2).Methods: Twelve sheep were divided into four groups and were given a single intrapleural injection of TGF beta(2) in a concentration of 1.0 microg/kg, 0.5 microg/kg, 0.25 microg/kg or 0.125 microg/kg to the right pleural cavity via a chest tube. The left pleural cavity served as the control. Any pleural fluid that accumulated after the intrapleural TGF beta(2) injection was collected and analysed. The degree of pleurodesis was graded from 1 (no adhesions) to 8 (complete symphysis >50% of chest wall) at day 14 when the sheep were killed. Biopsy specimens were taken from the lungs and extrapulmonary organs.Results: All sheep that received > or = 0.25 microg/kg TGF beta(2) developed excellent pleurodesis (score = 8) while those that received 0.125 microg/kg had a median score of 6. The pleurodesis score did not exceed 2 in the control (left) side of any sheep. Sheep receiving > or = 0.50 microg/kg TGF beta(2) developed large exudative pleural effusions while those receiving a lower dose did not. The production of effusions neither hindered nor was necessary for inducing pleurodesis. There were no significant fibrotic changes in any of the extrapulmonary organs.Conclusion: Intrapleural injection of 0.25-1.0 microg/kg TGF beta(2) produces excellent pleurodesis in a new sheep model with no evidence of extrapulmonary fibrosis. [ABSTRACT FROM AUTHOR]

The effects of protriptyline on sleep stage distribution and gas exchange have been assessed in eight patients with nocturnal hypoventilation secondary to restrictive chest wall disease. At a dose of 10-20 mg taken when they retired the total sleeping time was unaltered but the proportion of rapid eye movement (REM) sleep fell from 22% to 12% (p less than 0.05). The total time spent at an arterial oxygen saturation of less than 80% decreased (p less than 0.01) and the magnitude of the fall correlated with the reduction in REM sleep (r = 0.67, p less than 0.05). There was also a reduction in the maximum carbon dioxide tension reached during the night (p less than 0.01). The arterial oxygen tension measured diurnally increased (p less than 0.05) from a median of 8.0 kPa (60 mm Hg) to 9.0 kPa (67.5 mm Hg), but the carbon dioxide tension and base excess were unchanged. Anticholinergic side effects were experienced by most patients but did not limit treatment. [ABSTRACT FROM PUBLISHER]

Fresh allograft valves stored in a nutrient medium at +4 degrees C have a limited storage time of eight weeks. Dura mater has been stored in glycerol for longer periods, and this paper presents work on the glycerol storage of allograft heart valves. The elastic properties of the valve cusps showed a fall during storage in glycerol that was associated with an altered histological appearance of the cusp tissue. The loss in nuclearity in the histological sections of stored tissue was partially responsible for the observed decrease in viability during storage. All these changes during storage in glycerol, or glycerol and subsequent antibiotic treatment, were similar to the changes seen in valves stored in a nutrient medium. Glycerol therefore offers an alternative storage system to the cold nutrient medium but has no practical advantages. Glycerol alone will not sterilise the allograft tissue, and a post-storage treatment with antibiotics is essential. [ABSTRACT FROM PUBLISHER]

Some problems of cannulation of the ascending aorta are demonstrated. Improved perfusion of the aortic arch is subsequently shown with a metal cannula having a basket-shaped tip. The design of the tip breaks the perfusing jet into four weaker jets, thus preventing differential perfusion of an arch vessel. [ABSTRACT FROM PUBLISHER]

iThe article presents an image based overview of lymphangioma, which is a rare case of mediastinal mass. It highlights the examination of an asymptomatic patient being investigated for hypertension, whose computed tomographic (CT) scanning revealed a large low attenuation mass encasing the oesophagus extending from the carina to the diaphragm. The thoracoscopic biopsy specimen revealed ectatic vascular spaces, some of which contained lymph and others blood.