Genetic analysis of isolated persistent hypermethioninemia with dominant inheritance

We describe a type of mild hypermethioninemia due to a point mutation in the MATA1 gene, which was inherited dominantly in a family. Three patients coming from the same family pedigree were detected by the presence of isolated hypermethioninemia on a mass-screening program. The measurement of methionine adenosyltransferase (MAT) activity in a patient's liver revealed a partial deficiency of hepatic MAT with a reduction in the Km for methionine. Single strand conformation polymorphism (SSCP) analysis and direct sequencing of the patients' genomic DNA revealed a G to A mutation at nucleotide 791 that converts Arg-264 to His (R264H) in one allele of MATA1 gene. The other allele was normal in all the patients examined. Gene tracking in the family revealed that the hypermethioninemia is associated with heterozygosity for the R264H mutation in the MATA1 gene.     

Pharmacological Properties of Pteleprenine,a Quinoline Alkaloid Extracted from Orixa japonica,on Guinea-pig Ileum and Canine Left Atrium

We have investigated the pharmacological properties of pteleprenine, a quinoline alkaloid, on contractile responses of the guinea-pig ileum and on inotropic responses of the canine left atrium. Although pteleprenine (0·1–1 μM) had no effect on the contraction of the ileum induced by acetylcholine at 10 μM it significantly inhibited acetylcholine-induced contraction of the ileum. Pteleprenine (0·1–10 μM) reduced nicotine induced-contraction of the ileum in a concentration-dependent manner yet had no maximum relaxant effect even at a concentration of 10 μM From Schild analysis the pA₂ of pteleprenine on the guinea-pig ileum was found to be 6-6. The contraction of the ileum induced by 10 μM 1,1-dimethyl-4-phenylpiperazinium, a specific agonist of nicotinic acetylcholine. receptors, was concentration-dependently suppressed by 10 nM-10 μM pteleprenine. In contrast, 0.1–10 μM pteleprenine did not antagonize the acetylcholine- and nicotine-induced negative inotropic contractile responses of the canine left atrium. These results show that pteleprenine has inhibitory action against nicotinic acetylcholine receptors in the guinea-pig ileum but not in the canine left atrium. Our findings also suggest that pteleprenine might be a novel lead compound as a nicotinic receptor antagonist.     

Experience with flexible video cystoscope equipped with built-in high-frequency cauterizing element for transurethral resection of the bladder

We successfully treated three patients using the flexible video cystoscope (CYF-240A, Olympus, Japan) for superficial bladder cancer under local anesthesia and/or spinal anesthesia. The major advantage of this new technique is that surgeons can use digital pictures and high frequency cauterization. This new system provides good quality of life for bladder cancer patients experiencing frequent recurrences.     

Unfolding of tertiary structures of proteins

The unfolding pathway of lysozyme was investigated by carrying out the computer simulation. Taking into account the simultaneous change of both the dihedral angles ø and of a residue, we explore the detailed features of the conformational energy profiles. The triangle distance map shows that the lysozyme molecule is divided into three domains, 1–40, 41–101 and 102–129 in amino acid residue numbers (referred to as the domains I, II and III, respectively). The calculated unfolding process indicates that in the early stage of unfolding domain III located at the C-terminal begins to be detached from the other two, and then domain I can be unfolded. The long-range interactions between domains I and III stabilize the whole molecule and give the cooperative nature of the folding. The calculated unfolding pathway of lysozyme is consistent with the folding pathway proposed by Anderson & Wetlaufer [J. Biol. Chem. (1976). 251 , 3147–3153] who identified the disulfide bondings in the early stage of the glutathione regeneration. A simplified treatment of unfolding for myoglobin is also discussed in the Appendix.     

Analyses of proliferating cell nuclear antigen-positive cells in hepatocellular carcinoma: Comparisons with clinical findings

Abstract Proliferating tumour cells in 92 patients with hepatocellular carcinoma (HCC) were identified by an immunohistochemical method using a monoclonal antibody against proliferating cell nuclear antigen (PCNA). The rate of PCNA-positive cells in HCC tissues was positively correlated with histological grade and the tumour size and T factor of the tumour.
In order to analyse the relationship between prognostic factors and cumulative survival rate after obtaining tumour specimens, 49 patients whose clinical courses could be followed after needle biopsy were selected for evaluation. These patients were treated by medical therapy alone. Analyses of prognostic factors by Cox's proportional hazard model revealed that the patient's prognosis was significantly correlated with PCNA-positive rates as well as the tumour size and mode of therapy. Moreover, the cumulative survival rates were significantly ( P < 0.001) higher in patients with rates of PCNA-positive cells <15% than in those with ≧ 15%, even when tumour sizes were under 50 mm or tumours demonstrated the same degree of histological differentiation.
These findings indicate that the PCNA-positive rate in biopsied tissues provides useful prognostic information in patients with HCC treated only by medical therapy.     

慢性乙型肝炎患者肝组织内CD4+CD25+Foxp3+调节性细胞的作用

目的 观察慢性乙型肝炎患者肝内调节性T细胞(Treg)与病情活动、肝细胞损伤的关系.方法 对日本长崎大学医学院附属医齿学病院第一内科26例住院慢性乙型肝炎患者进行肝组织活检,采用免疫组织化学方法以单抗Foxp3、单抗CD3检测肝组织内Foxp3+细胞和CD3+细胞频率,计算Foxp3+/CD3+细胞比率,结合肝组织学炎症活动指数(HAI,采用Knodell评分系统)、ALT、AST、HBV DNA水平进行分析.数据用SPSS 13.0软件进行统计分析.结果 Foxp3+Treg主要分布在门脉区;Foxp3+/CD3+细胞(%)在肝实质重度炎症组明显高于轻度炎症组(P=0.007 6);Foxp3+/CD3+细胞(%)的增高与血清ALT、AST水平呈正相关,相关系数分别0.438、0.436(P值分别为0.025、0.026),与血清HBV DNA水平有相关趋势,但差异无统计学意义.结论 CD4+CD25+Foxp3+Treg在慢性乙型肝炎患者的发病机制中参与肝细胞的免疫损伤.