MRI of ossification of ligamentum flavum.

Magnetic resonance imaging of 28 patients with radiological and/or histopathologically proved ossification of the ligamentum flavum (OLF) was reviewed. The locations of OLF were cervical (n = 4), thoracic (n = 22), and lumbar (n = 2). On T1- and T2-weighted images, OLF demonstrated low signal intensity. Areas of high or intermediate signal intensity within the OLF on T1-weighted images were observed in three cases and were interpreted to be due to fat infiltration. In six cases, high intensity areas in the spinal cord caused by compressing OLF were demonstrated on T2-weighted images. Gadolinium-diethylenetriamine pentaacetic acid, which was used in four cases, showed cord enhancement at the level of compression by OLF in three cases.     

Surgical treatment of infected intralobar pulmonary sequestration: a collective review of patients older than 50 years reported in the literature.

We report on the rare and surgical treatment of a senile patient of infected intralobar pulmonary sequestration. A 56-year-old male who had complained of headache, vomiting, cough, sputum production, and high fever was admitted to our hospital. Chest computed tomography (CT) showed an infected intralobar pulmonary sequestration as an 8x6 cm cystic mass with multiple air-fluid cavities in the left lower basal segment and severe pneumonia in the left upper and lower lobes around the mass. A 3-D CT showed an aberrant artery entering the consolidation from the descending aorta. A standard lower lobectomy was performed with a ligation of the aberrant artery with a diameter of 1 cm supplying the posterior segment of the left lower lobe. A histological examination of the lung revealed acute and chronic broncho-bronchiolitis with cystic dilatation consistent with intralobar pulmonary sequestration. We discuss the characters of senile patients compared with juvenile patients, with reference to a collective review of patients older than 50 reported in the literature.     

B-cell repertoire specific for an unfolded self-determinant of mouse lysozyme escape tolerance and dominantly participate in the autoantibody response

We previously found that autoantibodies against mouse lysozyme (ML) were strongly induced in normal BALB/c mice when immunized with mutant ML that has triple mutations rendering the dominant T-cell epitope of hen egg lysozyme (HEL), HEL 107-116. As T cells specific for HEL 107-116 were primed in these mice, the anti-ML immunoglobulin G (IgG) responses would be the result of collaborations between autoreactive B cells specific for ML and T cells specific for HEL 107-116. Serum IgG responses against ML were dominantly focused on the ML 14-69 region, indicating that B cells responding to the epitope escape tolerance. In the present study, we prepared several monoclonal antibodies (mAbs) specific for ML 14-69 and examined their antigen specificities in detail, to characterize the nature of the remaining B-cell repertoire specific for ML. mAbs specific for ML 14-69 interacted weakly with soluble, native ML, but the interactions were strengthened by denaturation of ML. The apparent affinity constants between these mAbs and ML showed an increase, ranging from six- to 80-fold, by denaturation of ML. Therefore, these mAbs were more specific for the denatured determinant than for the determinant in the native structure. These results indicate that a substantial number of autoreactive B cells, specific for the unfolded conformation of ML, escape tolerance and are dominantly involved in the autoantibody response to ML. Our finding provides important information to understand the naturally occurring autoreactive B-cell repertoire in normal mice.     

Simultaneous Duodenal Metal Stent Placement and EUS-Guided Choledochoduodenostomy for Unresectable Pancreatic Cancer

Patients with pancreatic cancer frequently suffer from both biliary and duodenal obstruction. For such patients, both biliary and duodenal self-expandable metal stent placement is necessary to palliate their symptoms, but it was difficult to cross two metal stents. Recently, endoscopic ultrasonography-guided choledochoduodenostomy (EUS-CDS) was reported to be effective for patients with an inaccessible papilla. We report two cases of pancreatic cancer with both biliary and duodenal obstructions treated successfully with simultaneous duodenal metal stent placement and EUS-CDS. The first case was a 74-year-old man with pancreatic cancer. Duodenoscopy revealed that papilla had been invaded with tumor and duodenography showed severe stenosis in the horizontal portion. After a duodenal uncovered metal stent was placed across the duodenal stricture, EUS-CDS was performed. The second case was a 63-year-old man who previously had a covered metal stent placed for malignant biliary obstruction. After removing the previously placed metal stent, EUS-CDS was performed. Then, a duodenal covered metal stent was placed across the duodenal stenosis. Both patients could tolerate a regular diet and did not suffer from stent occlusion. EUS-CDS combined with duodenal metal stent placement may be an ideal treatment strategy in patients with pancreatic cancer with both duodenal and biliary malignant obstruction.     

Metastatic gastrinoma to the liver 20 years after primary resection

Gastrinoma is a rare endocrine tumor that is frequently associated with liver metastasis. The liver metastasis is usually seen simultaneously or soon after a primary operation. A 47-year-old woman who had had a total gastrectomy 20 years earlier developed liver metastasis. An interval of this length between surgery and metastasis is extremely rare. The total gastrectomy prevented the patient from developing the usual symptoms of hypergastrinemia that would have enabled early diagnosis of the metastasis. Laboratory examinations on admission revealed a high serum gastrin concentration (1500 pg/ml). Computed tomography showed an irregularly enhanced mass lesion with an uneven, low-density central area in the right anterior inferior segment of the liver. An extended right hepatectomy was performed. Intraoperative ultrasonography showed no abnormalities in the remnant pancreas. Examination of the cut surface of the specimen revealed a yellow, firm, elastic tumor, 55 mm in diameter. The interior of the tumor appeared necrotic. Histopathologically, the tumor was composed of cells with hyperchromatic, dysplastic nuclei arranged in a trabecular pattern with nest formation. Gastrin staining was positive. A histologic diagnosis of metastatic gastrinoma was made. The patient's gastrin concentration returned to normal and she was well at 2-year follow-up. Received: August 19, 1999 / Accepted: January 28, 2000     

Documented subacute stent thrombosis within thirty days after stenting with sirolimus-eluting stent (Cypher) for acute myocardial infarction: a Japanese single center retrospective non-randomized study.

BACKGROUND: The incidence of subacute stent thrombosis (SAT) within 30 days after stenting with a sirolimus-eluting stent (Cypher) for acute myocardial infarction (AMI) was retrospectively compared to that with bare-metal stents (BMS). METHODS AND RESULTS: Among 559 lesions in 558 consecutive AMI from April 2003 to February 2006, the incidence of documented SAT after Cypher implantation (2/276 lesions, 0.72%) was almost the same as for BMS (2 cases, 0.71%). Aspirin (81-100 mg/day) plus ticlopidine (200 mg/day) were administered continuously after admission in all 4 cases. CONCLUSION: Documented SAT did not increase after stenting with Cypher for AMI under aspirin plus ticlopidine.