Effects of tract embolization on pneumothorax rate after percutaneous pulmonary microwave ablation: a rabbit study

AbstractPurpose To determine the effects of tract embolization with gelatin sponge particles on the prevention of pneumothorax after percutaneous microwave ablation (MWA) in rabbit lungs.Materials and methods Twenty-four New Zealand white rabbits were randomly divided into Group A (MWA followed by tract embolization with gelatin sponge particles, n = 12) and Group B (MWA without tract embolization, n = 12). For each group, CT images were reviewed for the occurrence of pneumothorax within 30 min after MWA. The rate of pneumothorax was compared by Chi-square Test. Lung tissue around the needle tract was harvested after the rabbits were euthanized, and histopathological examinations were performed and studied with hematoxylin and eosin stains.Results Twenty-four animals underwent 47 sessions of MWA (24 sessions in Group A and 23 sessions in Group B). Group A had a statistically lower rate of pneumothorax than Group B (25.0 vs. 56.5%; p = 0.028). The pathological examinations of both groups demonstrated thermal injury of the needle tract characterized by a rim of the coagulated lung parenchyma, which might be responsible for pneumothorax after MWA. Gelatin sponge particles could be arranged in irregular flakes densely to effectively seal the needle tract, thus reducing the occurrence of pneumothorax. The gelatin sponge particles could be almost completely absorbed about 14 days later.Conclusion Results of the present study showed needle tract embolization with gelatin sponge particles after CT-guided pulmonary MWA can significantly reduce the incidence of pneumothorax. Gelatin sponge particles can effectively seal the needle tract after ablation and can be completely absorbed in the body with good safety

Automated annotation of Drosophila gene expression patterns using a controlled vocabulary

Motivation: Regulation of gene expression in space and time directs its localization to a specific subset of cells during development. Systematic determination of the spatiotemporal dynamics of gene expression plays an important role in understanding the regulatory networks driving development. An atlas for the gene expression patterns of fruit fly Drosophila melanogaster has been created by whole-mount in situ hybridization, and it documents the dynamic changes of gene expression pattern during Drosophila embryogenesis. The spatial and temporal patterns of gene expression are integrated by anatomical terms from a controlled vocabulary linking together intermediate tissues developed from one another. Currently, the terms are assigned to patterns manually. However, the number of patterns generated by high-throughput in situ hybridization is rapidly increasing. It is, therefore, tempting to approach this problem by employing computational methods