Dan E. Olson

The c-myc x E2F-1/p21 interactive gene expression index augments cytomorphologic diagnosis of lung cancer in fine-needle aspirate specimens

Morphological analysis of cytologic samples obtained by fine-needle aspirate (FNA) or bronchoscopy is an important method for diagnosing bronchogenic carcinoma. However, this approach has only about 65 to 80% diagnostic sensitivity. Based on previous studies, the c-myc x E2F-1/p21WAF1/CIP1 (p21 hereafter) gene expression index is highly sensitive and specific for distinguishing normal from malignant bronchial epithelial tissues. In an effort to improve sensitivity of diagnosing lung cancer in cytologic specimens, we used Standardized Reverse Transcriptase Polymerase Chain Reaction (StaRT-PCR) to measure the c-myc x E2F-1/p21 index in cDNA samples from 14 normal lung samples (6 normal lung parenchyma and 8 normal bronchial epithelial cell [NBEC] biopsies), and 16 FNA biopsies from 14 suspected tumors. Based on cytomorphologic criteria, 11 of the 14 suspected tumors were diagnosed as bronchogenic carcinoma and three specimens were non-diagnostic. Subsequent biopsy samples confirmed that the three non-diagnostic samples were derived from lung carcinomas. The index value for each bronchogenic carcinoma was above a cut-off value of 7000 and the index value of all but one normal sample was below 7000. Thus the c-myc x E2F-1/p21 index may augment cytomorphologic diagnosis of bronchogenic carcinoma biopsy samples, particularly those considered non-diagnostic by cytomorphologic criteria.

Flow simulation in a 3D model of pig airways and connection to lung sounds

Fundamental to the understanding of the various transport processes within the respiratory system, airway fluid dynamics plays an important role in biomedical research. When air flows through the respiratory tract, it is constantly changing direction through a complex system of curved and bifurcating tubes. As a result, numerical simulations of the airflow through this tracheobronchial system must be capable of resolving such fluid dynamic phenomena as flow separation, recirculation, secondary flows due to centrifugal instabilities, and shear stress variation along the airway surface. Anatomic complexities within the tracheobronchial tree, such as sharp carinal regions at asymmetric bifurcations, have motivated the application of the incompressible Computational Fluid Dynamics code PHI3D to the modeling of airflow. Developed at ORNL, PHI3D implements the new Continuity Constraint Method. Using a finite-element methodology, complex geometries can be easily simulated with PHI3D using unstructured grids. A time- accurate integration scheme allows the simulation of both transient and steady-state flows. A realistic geometry model of the central airways for the fluid flow studies was obtained from pig lungs using a new high resolution x-ray computed tomography system developed at ORNL for generating 3D images of the internal structure of laboratory animals.

Empyema due to severe Pasteurella multocida treated with quinolone: a case report.

Pasteurella multocida (PM) is gram-negative coccobacillus that is commonly acquired through a cat scratch or bite. The standard antibiotic of choice for treating PM is penicillin. We present a case of PM empyema in a penicillin allergic 56-year-old female who has a history of contact with domestic cats and is known to have chronic obstructive pulmonary disease and a chronic history of smoking. The patient was treated successfully with Levofloxacin as alternative treatment to penicillin.