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Background: The management of pulmonary nodules relies on cancer risk assessment, in which the only widely accepted criterion is diameter. The development of volumetric computed tomography (CT) and three-dimensional (3D) software enhances the clarity in displaying the nodules' characteristics. This study evaluated the values of the nodules' volume and 3D morphological characteristics (edge, shape and location) in cancer risk assessment., Methods: The CT data of 200 pulmonary nodules were retrospectively evaluated using 3D volumetric software. The malignancy or benignity of all the nodules was confirmed by pathology, histology or follow up (>2 years). Logistic regression analysis was performed to calculate the odds ratios (ORs) of the 3D margin (smooth, lobulated or spiculated/irregular), shape (spherical or non-spherical), location (purely intraparenchymal, juxtavascular or pleural-attached), and nodule volume in cancer risk assessment for total and sub-centimeter nodules. The receiver operating characteristic (ROC) curve was employed to determine the optimal threshold for the nodule volume., Results: Out of 200 pulmonary nodules, 78 were malignant, whereas 122 were benign. The Logistic regression analysis showed that the volume (OR=3.3; P<0.001) and the 3D margin (OR=13.4, 9.8; both P=0.001) were independent predictive factors of malignancy, whereas the location and 3D shape exhibited no total predictive value (P>0.05). ROC analysis showed that the optimal threshold for malignancy was 666 mm³. For sub-centimeter nodules, the 3D margin was the only valuable predictive factor of malignancy (OR=60.5, 75.0; P=0.003, 0.007)., Conclusions: The volume and 3D margin are important factors considered to assess the cancer risk of pulmonary nodules. Volumes larger than 666 mm³ can be determined as high risk for pulmonary nodules; by contrast, nodules with lobulated, spiculated, or irregular margin present a high malignancy probability.

The hyperthermophilic α-amylase from Thermococcus sp. HJ21 possesses unique traits (Ca(2+)-independent thermostability and optimal temperature of 95°C) that make it a great potential candidate for use in the food industry. However, this Archaea isolated from a deep-sea thermal vent requires strict control of culture conditions and produces only small amounts of α-amylase. To solve these problems, the α-amylase gene was cloned and expressed in Bacillus subtilis, which is an ideal food-grade host for heterologous protein expression. To express high levels of this α-amylase in B. subtilis, the promoters Pgrac, PxylA, P43, and Phag were used to construct four different expression vectors for testing. The vector containing the PxylA promoter was found to have the highest transcriptional activity and produce the highest amylase activity (19.6 U/ml). To test the secretion efficiency of signal peptides in B. subtilis, three signal peptides were cloned and fused to the α-amylase gene (lacking its native signal peptide). The optimal signal peptide was SamyQ, with a secretion efficiency of approximately 90%. These results indicate that the promoter PxylA and signal peptide SamyQ tested in this study may be useful for the expression and secretion of archaeal proteins in B. subtilis., (Copyright © 2013 S. Karger AG, Basel.)