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Under certain conditions such as hypoxia-reoxygenation, the generation of reactive oxygen species (ROS) increases following hypoxia caused by a decreased oxygen supply. As another hypoxic condition, an excess neural activity status including epileptic seizure induces a decrease in tissue oxygen partial pressure (pO2) caused by enhanced oxygen utilization; however, whether ROS generation increases following the hypoxic status induced by transiently enhanced energy metabolism in brain tissue currently remains unknown. We herein investigated ROS-dependent chemiluminescence in cerebral cortex slices during the restoration of transiently enhanced energy metabolism induced by a high-potassium treatment with tissue pO2 changes and redox balance. ROS generation in the tissue was enhanced after high-potassium-induced hypoxia, but not by the reversed order of the treatment: control-potassium then high-potassium treatment, high-potassium treatment alone, and control-potassium treatment alone. The high-potassium treatment induced a transient decrease in tissue pO2 and a shift in the tissue redox balance towards reduction. The transient shift in the tissue redox balance towards reduction with enhanced metabolic activity and its recovery may correlate with ROS generation. This phenomenon may mimic ROS generation following the hypoxic status induced by transiently enhanced energy metabolism.

A 47-years-old man with hemodynamic shock was refered to our hospital by an ambulance. Chest computed tomography(CT)showed left hemothorax and the extravasation of contrast media in his left lung. Emergency operation was done. A lot of intrathoracic hematoma and pulsating bleeding from the lung was found, and lingular segmentectomy was performed. Pathologically, the rupture of pulmonary artery of 2.2 mm in diameter was found without the finding of imflammation nor degeneration due to any basal diseases. Around the lesion, some artery of 0.3~3.0 mm in diameter showed defect of tunica media. This vascular anomaly was considered to lead his hemothorax.

A 66-year-old man, who had undergone surgical resection of a primary noninvasive thymoma (type B1) in the right anterolateral mediastinum 6 years before, underwent follow-up computed tomography (CT) scanning. The CT scan revealed a few nodules located at the posterior portion of the right thoracic base and just behind the right upper anterior chest wall. Subsequent fluorodeoxyglucose positron emission tomography (FDG-PET) scans showed multiple foci with high [standard uptake value (SUV) 4.3] and low (SUV 2.6) FDG uptake in the right lower posterior area and right upper anterior area of the chest, respectively. The fusion image of the CT and FDG-PET scans demonstrated that the areas of the increased FDG uptake corresponded to those of the nodules on the CT scan. All of the nodules were successfully removed surgically, and the histological features of the nodules indicated that they were type B1 or types B1 plus B2. We regarded the nodule located just behind the right upper anterior chest wall as a type B1 thymoma, whereas those in the posterior area of the right thoracic base as combined thymomas of types B1 plus B2. Our limited experience suggests that the degree of FDG uptake is a reflection of the subtype according to the World Health Organization (WHO) criteria. Furthermore, we showed the role of FDG-PET in the accurate assessment of recurrent thymoma and its therapeutic strategy.

Recent studies have shown the possible role of growth factors and the involvement of macrophages as a source of them in the pathogenesis of bronchiolitis obliterans (BO) after lung transplantation.The authors intended to determine whether depletion of recipient macrophages by gadolinium chloride (GdCl3) resulted in decreased obliterative airway disease (OAD) in a rat model of heterotopic tracheal transplantation.A tracheal segment of donor rats (Brown Norway) was transplanted into a subcutaneous pouch of fully major histocompatibility complex-incompatible recipient rats (Lewis). Recipients were injected intravenously with 80 mg/kg of GdCl3.6H2O or saline on days 0, 7, and 14 posttransplant. Allografts were harvested on days 7, 14, 17, and 21 and the degree of OAD resulting from fibroproliferative tissue was pathologically scored on a scale of 0 to 4. A portion of allografts was submitted to reverse-transcriptase polymerase chain reaction analysis to examine mRNA expression for platelet-derived growth factor (PDGF), basic fibroblast growth factor, and transforming growth factor-beta1.Immunohistochemical studies confirmed reduction in the number of ED2+ macrophages in tracheal allografts by GdCl3 injection. GdCl3 treatment significantly decreased OAD of allografts, with the histologic score of 1.4+/-0.3 in the treated animals compared with 3.0+/-0.5 in the controls (mean+/-SE, P=0.02) at day 21 posttransplant, and this was accompanied by decreased PDGF-A and PDGF-B gene expression in the GdCl3 group at day 17 posttransplant.Macrophage reduction by GdCl3 resulted in significantly decreased OAD development and reduced PDGF mRNA expression in allografts. This suggests a potential effectiveness of therapies targeting recipient macrophages in preventing BO after lung transplantation.

We report a case of chest wall abscess caused by Mycobacterium bovis BCG that arose as a complication 1 year after intravesical BCG instillation. We identified M. bovis BCG Tokyo 172 in the abscess by PCR-based typing of Mycobacterium tuberculosis complex and analysis of variable number of tandem repeats data.

Effect of alpha-adrenergic blockers on pulmonary edema in lung transplantation was studied with a rat model of syngeneic left lung transplantation. Prior to harvesting, 0.1 mg of Prazosin or 0.4 mg of Yohimbine was given to the donor. Pulmonary and systemic hemodynamics were measured under the right pulmonary arterial occlusion (RPAO) at different time points after grafting. Wet to dry weight ratio (W/D) of all transplants was also calculated. Same procedure was conducted in rats with normal and ischemic lung and in transplanted animals without any treatments. While RPAO did not increase W/D in normal lung with a significant elevation in pulmonary arterial pressure (PAP), both these values significantly increased in transplanted lung. Transplanted animals could not tolerate RPAO 24 hours after grafting, but were tolerable later than 48 hours with elevated W/D and PAP. On the contrary, animals given Prazosin or Yohimbine were all tolerable at 24 hours postsurgery. Yohimbine significantly improved W/D. Consequently, it was demonstrated that pulmonary edema of the graft reached its peak during first 24 to 48 hours after transplantation and was alleviated by the blockade of alpha-adrenergic receptor in the graft vessel.