Replacement of the Catalytic Nucleophile Aspartyl Residue of Dextran Glucosidase by Cysteine Sulfinate Enhances Transglycosylation Activity

Dextran glucosidase from Streptococcus mutans (SmDG) catalyzes the hydrolysis of an α-1,6-glucosidic linkage at the nonreducing end of isomaltooligosaccharides and dextran. This enzyme has an Asp-194 catalytic nucleophile and two catalytically unrelated Cys residues, Cys-129 and Cys-532. Cys-free SmDG was constructed by replacement with Ser (C129S/C532S (2CS), the activity of which was the same as that of the wild type, SmDG). The nucleophile mutant of 2CS was generated by substitution of Asp-194 with Cys (D194C-2CS). The hydrolytic activity of D194C-2CS was 8.1 × 10⁻⁴ % of 2CS. KI-associated oxidation of D194C-2CS increased the activity up to 0.27% of 2CS, which was 330 times higher than D194C-2CS. Peptide-mapping mass analysis of the oxidized D194C-2CS (Ox-D194C-2CS) revealed that Cys-194 was converted into cysteine sulfinate. Ox-D194C-2CS and 2CS shared the same properties (optimum pH, pI, and substrate specificity), whereas Ox-D194C-2CS had much higher transglucosylation activity than 2CS. This is the first study indicating that a more acidic nucleophile (-SOO−) enhances transglycosylation. The introduction of cysteine sulfinate as a catalytic nucleophile could be a novel approach to enhance transglycosylation

Assessment of nonlinear site response at ocean bottom seismograph sites based on S-wave horizontal-to-vertical spectral ratios: a study at the Sagami Bay area K-NET sites in Japan

Additional file 4. Relationship between DNL values and PGAs at the OBS and land sites

Nonfunctioning endocrine tumor of the pancreas：A case report

We report a rare case of a very large nonfunctioning endocrine tumor of the pancreas without malignant histological features. A 63-year-old woman referred for appetite loss and general fatigue was found to have a tumor in the pancreas head. Computed tomography demonstrated a well-defined pancreatic tumor 45mm in diameter with hypervascular staining in the pancreas head. Angiography showed a hypervascular tumor of the pancreas head and a dilatation of the anterior superior and posterior superior pancreaticoduodenal arteries. The preoperative diagnosis was an endocrine tumor of the pancreas, with undeniable malignancy. Pylorus-preserving pancreaticoduodenectomy was performed. The histopathological diagnosis was a benign nonfunctioning endocrine tumor of the pancreas based on immunohistochemical staining for Chromogranin A, Synaptophysin, and NSE, but not for hormones. The tumor revealed a low labeling index (<2.0%) of Ki-67 indicating its benign character. No tumor recurrence has been identified in the 18 months since surgery

Primary research on MGSAD023, a new homokogue of eIF4G

Abstruct MGSAD023 (Mouse Gene Similar to AD023; Genbank accession AK150749) and its human compartment (AD023; Genbank accession AF225422) are new two genes with unknown functions. They were derived from high-throughput cDNA sequence analysis of the mouse genome project and Human Genome Project (HGP)，respec- tively. MGSAD023 shows 88.6% identity to AD023 (NCBI Blast)，and we decided to use MGSAD023 as a temple to explore the functions of these two compartment genes. With the NCBI Conserved Domain Database (CDD) and the gap program in GCG se- quence analysis software，we found that the amino acids of MGSAD023 showed 58.3% similarity and 4l.2% identity to eIF4G and also showed a good match to the middle domain of eIF4G. We determined the transcription pattern of MGSAD023. RT-PCR results showed that MGSAD023 was expressed in all of the tissues checked，including cerebellum， cerebra，liver，kidney，tongue，testis，heart and spleen，without any significant differ- ences.The results of In Situ Hybridization (ISH) showed that there was a very strong signal of mRNA of MGSAD023 on the seminiferous tubular basement membrane， where spermatogonia A and B are located. In silico exploration revealed homologous genes in various species，i ncluding chimpanzee，rat，mice，dog，zebra fish，fruit fly， xenopus，and cattle. These results hint that MGSAD023 is a conserved gene. It may act as a translation factor during cellular mitosis，especially in spermatogonia

タンノウ テキシュツジュツ デ チュウイ スベキ タンカン ソウコウ イジョウ Cystohepatic duct ノ 1レイ

　A 74-year-old man presented with epigastralgia and was diagnosed as having cholelithiasis. Endoscopic retrograde cholangiopancreatography (ERCP) initially visualized the cystic duct with the Heister valve from the common bile duct, and then two intra-hepatic biliary ducts of segment 5 (B5) were visualized from the neck of the gallbladder. There was a contrast medium filling defect in B5, which was considered to be due to an incarcerated stone. Magnetic resonance cholangiopancreatography (MRCP) and three-dimensional computed tomography (CT) cholangiography showed similar findings, suggesting that the patient had a biliary anomaly of the cystohepatic duct in which two intrahepatic bile ducts (B5) flowed into the neck of the gallbladder and a stone incarcerated in the neck of the gallbladder.　At surgery, during mobilization of the gallbladder, there was a thick string between the liver and the gallbladder, and this was considered to be the junction of B5 with the gallbladder. Therefore, the neck of the gallbladder was cut, and an incarcerated stone 10 mm in diameter was removed. Intraoperative cholangiography revealed that the cystohepatic ducts were preserved. The postoperative course was uneventful and there was no bile leakage or liver dysfunction.　Although cystohepatic duct is a rare biliary anomaly, the surgeon should be alert for its possible presence during cholecystectomy. When cholecystectomy is scheduled, more than one preoperative examination by three-dimensional CT cholangiography, MRCP or ERCP should be performed, and the surgeon should be careful not to overlook any biliary anomaly.　Keywords: cystohepatic duct, biliary duct anomaly, cholecystectomy, three-dimensional computed tomography, gallston