Tatsuhiko Hayashi

Methylation imprinting was observed of mouse mo-2 macrosatellite on the pseudoautosomal region but not on chromosome 9

Mouse mo-2 macrosatellites consisting of 31-bp tandem repeat units are mainly located at two loci in the C57BL/6 genome, one being at the centromere-distal telomeric region of chromosome 9 and the other at the pseudoautosomal (PA) region of chromosomes X and Y. The two clustes constitute approximately 300 kb and 150 kb, respectively. Southern analysis of a methylation-sensitive enzyme, HpaII-digested DNA showed that the mo-2 macrosatellites are detected as more than 30 polymorphic bands. Comparison of those bands between reciprocally crossed F1 mice revealed that approximately 20% of the allele-specific fragments exhibit different band intensities depending on the sex of the parent of origin. The differential methylation is observed in the mo-2 macrosatellite on the PA region but not in that on chromosome 9. Several fragments including the 3.4-kb fragment without internal HpaII site are more clearly detected when paternally derived, suggesting that the male-derived macrosatellite is undermethylated. Interestingly the difference is much more remarkable in inter-subspecific F1 mice between C57BL/6 and MSM than F1 between C57BL/6 and C3H/He. This suggests the presence of a modifier(s) that affect(s) the methylation of mo-2 in the MSM genome.

Nonoperative treatment of reperforated duodenal ulcer: report of three cases.

Abstract During the period between 1983 and 1998, a total of 58 patients were admitted to the surgical department of Akita Red Cross Hospital with acute duodenal perforation. Of these 58 patients, 16 were treated operatively and 42 were treated nonoperatively. Among the 38 men and 4 women who received nonoperative treatment, 3 developed reperforation. The incidence of reperforation was 7.1% and the mean average interval from the initial treatment until reperforation was 3.5 years. Endoscopic biopsy and/or serum anti-H. pylori IgG measurement revealed Helicobacter pylori infection in all three patients. No serious complications developed during the nonoperative treatment of reperforation in these three patients, and their recovery was uneventful. The hospital stay ranged from 10 to 18 days, with a mean stay of 12 days after the first perforation and from 14 to 18 days, with a mean stay of 15.6 days after the reperforation. Nonoperative treatment proved successful as a life-saving procedure for reperforation of a duodenal ulcer in all three patients.

Low-grade dysplasia in an adenomatous polyp of the esophagus developing on pyloric-type heterotopic gastric mucosa treated with endoscopic mucosal resection: a case report

A 72-year-old woman with an unremarkable medical history underwent an upper gastrointestinal endoscopy in May 2002 because of dyspepsia. An examination showed a pedunculated polyp lesion in an inlet patch on the posterior wall of the esophagus, 20 cm distant from the incisors and measuring 1.5 cm. Forceps biopsies were obtained, and the pathological analysis showed a gastric-like mucosa with well-differentiated pyloric glands below an atrophic squamous epithelium; most of the glands were lined with atypical cells, compatible with low-grade dysplasia. Histological examination after endoscopic removal showed a low-grade dysplasia in an adenomatous polyp of the esophagus developing on pyloric-type heterotopic gastric mucosa (HGM). Three years later, the patient remains well with no evidence of esophageal disease. We review 25 reported cases of adenocarcinoma and 3 cases of high-grade dysplasia arising in HGM.

A Case Report of Successful Surgical Management of Malignant Melanoma at the Palate and Sigmoid Colon after the Excision of Cervical Lymphnodes Metastasis.

頸部リンパ節転移巣切除9年後, S状結腸病変切除2年1か月後に口蓋底原発巣が発見され, 共に切除可能であった悪性黒色腫の1例を経験した.症例は83歳, 男性.74歳時に, 左頸部リンパ節摘出術の既往がある.1989年1月 (81歳), S状結腸悪性黒色腫に対し, S状結腸切除術施行.この際, 前述の左頸部リンパ節も悪性黒色腫の転移であることが確認された.1989年10月, 悪性黒色腫頸部リンパ節転移再発, 甲状腺癌髄様型にて左半甲状腺切除術, リンパ節郭清術施行.1990年6月, 口蓋底左側に悪性黒色腫原発巣を認め, 口蓋底部分切除術施行, 以後外来にて経過観察中であるが, 現在まで再発の兆候は認められておらず, 悪性黒色腫の消化管転移例としては良好な経過をとっており, 本例に対しては外科的治療が有効であったと考えられる.本邦での悪性黒色腫消化管転移切除例の7例ではいずれも症状の改善を見ており, 単発転移例では手術適応があると思われる.