Evaluation of diseased coronary arterial branches by polar representations of thallium-201 rotational myocardial imaging

The perfusion territories in polar representations of stress Tl-201 rotational myocardial imaging in patients with angina pectoris who had one diseased coronary segment were analyzed. The lesions proximal or distal to the first major septal perforator in left anterior descending arteries were detected by the presence or absence of defects at the base of the anterior septum. Right coronary artery lesions were detected by the presence of defects at the basal posterior septum, in contrast to the preservation of myocardial uptake at this portion in lesions of the left circumflex artery. The specific defect patterns were detected in cases with lesions at the first diagonal, obtuse marginal, and posterolateral branches. Recognition of these defects in the polar maps allows detailed detection of diseased coronary arterial branches.     

Oscillator mechanism of Notch pathway in the segmentation clock.

Somites are formed by periodic segmentation of the presomitic mesoderm (PSM). This periodic event is controlled by the segmentation clock, where Notch signaling plays an essential role. The basic helix-loop-helix factor Hes7, a Notch effector, is cyclically expressed by negative feedback and regulates cyclic expression of Lunatic fringe (Lfng), a Notch modulator. Lfng then seems to periodically inhibit Notch, leading to oscillation in Notch activity. It is thought that these coupled negative feedback loops by Hes7 and Lfng are important for sustained and synchronized oscillations in the PSM. Of interest, another Notch effector, Hes1, is cyclically expressed by many cell types such as neuroblasts, suggesting that this clock is widely distributed and regulates many biological events. This review summarizes the recent finding about roles and mechanism of Notch signaling in the segmentation clock and discusses the significance of Hes1 oscillation in non-PSM cells.     

Pericardial effusion following pulmonary resection

Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198)     

CHARACTERISTICS OF HISTIOCYTIC LESIONS IN THE RETICULOENDOTHELIAL SYSTEM OF NZB MICE

The so-called Potter's lesion, previously described as preneoplastic in the lymph nodes of C58 mice, develops frequently in autoimmune NZB mice. These lesions were characterized in the present study by bands or sheets of palestaining histiocytic cells in the cortex and medulla of the lymph node, and multiple small nodules of the same cells were found in the red pulp of the spleen and the liver. Electron microscopically, the cells had pleomorphic cytoplasm with long processes, electron-dense bodies, abundant mitochondria, and a characteristic labyrinth structure with many C-type viruses. Mac-1 antigen, IgG-Fc receptor, ferritin, and ACPase activity were identified on these cells. Intraperitoneally-injected iron colloids were found in the lesions of the spleen and liver but not in those of the lymph nodes. The lymph node lesions appeared when the mice were about 3 months of age and enlarged until the mice were around 10 months old, after which they gradually receded and were replaced by small vessels and fibroblastic cells. These data indicate that the lesions represent reactive hyperplasia of the macrophage system and may have no direct association with the development of malignant lymphoma in NZB mice.     

Asymptomatic primary mucinous cystadenocarcinoma of the appendix with a large abdominal mass: Report of a case

A case of cystadenocarcinoma of the appendix with a large cystic lesion is reported. A 49-year-old man undergoing a routine ultrasonic scan was incidentally found to have an abdominal mass measuring some 30 cm in size. The clinical presentation was asymptomatic, and the patient underwent a laparotomy without ascertaining a diagnosis preoperatively. The lesion, which derived from the appendix, was removed and was found to be cystic and contained huge amounts of mucin. The histological findings revealed a well-differentiated cystadenocarcinoma of the appendix, and immunohistochemical staining of the epithelium and mucinous implants in the mass demonstrated a positive reaction for carcinogenic antigens, including carcinoembryonic antigen and carbohydrate antigen.