Left main bronchus resection and reconstruction. A single institution experience

<p>Abstract</p> <p>Background</p> <p>Left main bronchus resection and reconstruction (LMBRR) is a complex surgical procedure indicated for management of inflammatory, benign and low grade malignant lesions. Its application provides maximal parenchymal sparing.</p> <p>Methods</p> <p>Out of 98 bronchoplastic procedures performed at the Authors' Institution in the 1995-2011 period, 4 were LMBRR. Indications were bronchial carcinoid in 2 cases, inflammatory pseudotumor in 1 case, TBC stricture in 1 case. All patients underwent preoperatively a rigid bronchoscopy to restore the airway lumen patency. At surgery a negative resection margin was confirmed by frozen section in the neoplastic patients. In all patients an end-to-end bronchial anastomosis was constructed according to Grillo.</p> <p>Results</p> <p>There were neither mortality nor major complications. Airway lumen was optimal in 3 patients, good in 1.</p> <p>Conclusion</p> <p>LMBRR is a valuable option for the thoracic surgeon. It maximizes the parenchyma-sparing philosophy, broadening the spectrum of potential candidates for cure. It remains a technically demanding procedure, to be carried out by an experienced surgical team. Correct surgical planning affords excellent results, both in the short and long term.</p

Chance mechanisms affecting the burden of metastases

BACKGROUND: The burden of cancer metastases within an individual is commonly used to clinically characterize a tumor's biological behavior. Assessments like these implicitly assume that spurious effects can be discounted. Here the influence of chance on the burden of metastasis is studied to determine whether or not this assumption is valid. METHODS: Monte Carlo simulations were performed to estimate tumor burdens sustained by individuals with cancer, based upon empirically derived and validated models for the number and size distributions of metastases. Factors related to the intrinsic metastatic potential of tumors and their host microenvironments were kept constant, to more clearly demonstrate the contribution from chance. RESULTS: Under otherwise identical conditions, both the simulated numbers and the sizes of metastases were highly variable. Comparable individuals could sustain anywhere from no metastases to scores of metastases, and the sizes of the metastases ranged from microscopic to macroscopic. Despite the marked variability in the number and sizes of the metastases, their respective growth times were rather more narrowly distributed. In such situations multiple occult metastases could develop into fully overt lesions within a comparatively short time period. CONCLUSION: Chance can have a major effect on the burden of metastases. Random variability can be so great as to make individual assessments of tumor biology unreliable, yet constrained enough to lead to the apparently simultaneous appearance of multiple overt metastases

Schaedigung humaner Lungenzellen durch Ozon

The results of the present investigation as to the influence of gaseous ozone on cultivated human lung fibroblasts are based on a specific assay system established in our lab which permitted to bring both the gaseous toxicant and the cellular monolayer into intimate contact. Our assays used cultivated monolayers of human lung fibroblasts grown from operation biopsies from putatively healthy lung tissue. Influence of 0.5 ppm ozone for 20 hours induced an increase in cell mortality by 29%, whereas 2.5 ppm ozone for 4 hours increased fibroblast mortality by 74%. Lung fibroblasts damaged by ozone display the light-microscopical characters of a ''vitreous'' nucleus and characteristic protuberances of their surfaces. Electron-microscopical investigations revealed either undamaged cells or deceased fibroblasts, with no intermediate stages typical of ozone-damage being evident in cellular ultrastructure. Ozone induced changes of cell metabolism, were investigated. Cytotoxic effects of ozone could be lowered by the addition of asorbic acid (vitamin C) to culture media either during experiments, or by preincubation of cells with ascorbic acid prior to application to ozone. E.g., the addition of 1 mM ascorbic acid to media or preincubation with that vitamin concentration lowered the cellular mortality observed after 5 ppm ozone for 4 hours by 22%. Fibroblast clones grown from various human individuals displayed a very well-marked variability in their reaction to the toxicant. (orig./MG)Die vorliegende Untersuchung zu Auswirkungen des Umweltschadgases Ozon (O_3) auf nicht transformierte menschliche Lungenfibroblasten beruht auf einem Versuchssystem, das den direkten Kontakt von Zellen und Ozon gewaehrleistet. Zunaechst wurde die routinemaessige Anzuechtung menschlicher Fibroblasten aus OP-Lungenresektaten im Labor etabliert. Die Mortalitaet der ozonbehandelten Fibroblasten (Trypanblau-Exclusionstest) erhoehte sich nach Einwirkung von 0,5 ppm Ozon ueber 20 h um 29%, und nach 2,5 ppm Ozon ueber 4 h um 74%. Ozongeschaedigte Fibroblasten zeigten im Lichtmikroskop einen glasigen Zellkern und blasige Ausstuelpungen ihrer Oberflaeche. Ultrastrukturell konnten nach Ozonexposition nur entweder voellig zerstoerte oder gegenueber der Kontrolle unveraenderte Zellen nachgewiesen werden. Verschiedene metabolische Auswirkungen der Ozonimmission wurden ebefalls untersucht. Die toxischen Effekte von Ozon konnten durch Zugabe von Ascorbinsaeure zum Versuchsmedium, aber auch durch die alleinige Inkubation der Zellen mit Vitamin C vor Versuchsbeginn, abgemildert werden. Die Reduktion der Zellmortalitaet durch 1 mM Ascorbinsaeure nach 5 ppm Ozon ueber 4 h betrug 22%. Die von unterschiedlichen Spendern angezuechteten Fibroblasten zeigten eine bemerkenswerte Variabilitaet in ihrer Reaktion auf Ozon. (orig./MG)Available from TIB Hannover: RR 772(8) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLELand Baden-Wuerttemberg, Stuttgart (Germany)DEGerman