A thiol-mediated active membrane transport of selenium by erythroid anion exchanger 1 protein

In this paper, we describe a thiol-mediated and energy-dependent membrane transport of selenium by erythroid anion exchanger 1 (AE1, also known as band 3 protein). The AE1 is the most abundant integral protein of red cell membranes and plays a critical role in the carbon dioxide transport system in which carbon dioxide is carried as bicarbonate in the plasma. This protein mediates the membrane transport of selenium, an essential antioxidant micronutrient, from red cells to the plasma in a manner that is distinct from the already known anion exchange mechanism. In this pathway, selenium bound to the cysteine 93 of the hemoglobin β chain (Hb-Cysβ93) is transported by the relay mechanism to the Cys317 of the amino-terminal cytoplasmic domain of the AE1 on the basis of the intrinsic interaction between the two proteins and is subsequently exported to the plasma via the Cys843 of the membrane-spanning domain. The selenium export did not occur in plain isotonic buffer solutions and required thiols, such as albumin, in the outer medium. Such a membrane transport mechanism would also participate in the export pathways of the nitric oxide vasodilator activity and other thiol-reactive substances bound to the Hb-Cysβ93 from red cells to the plasma and/or peripherals

Functional expression of thiocyanate hydrolase is promoted by its activator protein, P15K

AbstractThiocyanate hydrolase (SCNase) is a cobalt-containing enzyme with a post-translationally modified cysteine ligand, γCys131-SO2H. When the SCNase α, β and γ subunits were expressed in Escherichia coli, the subunits assembled to form a hetero-dodecamer, (αβγ)4, like native SCNase but exhibited no catalytic activity. Metal analysis indicated that SCNase was expressed as an apo-form irrespective of the presence of cobalt in the medium. On the contrary, SCNase co-expressed with P15K, encoded just downstream of SCNase genes, in cobalt-enriched medium under the optimized condition (SCNase(+P15K)) possessed 0.86 Co atom/αβγ trimer and exhibited 78% of the activity of native SCNase. SCNase(+P15K) showed a UV–Vis absorption peak characteristic of the SCNase cobalt center. About 70% of SCNase(+P15K) had the γCys131-SO2H modification. These results indicate that SCNase(+P15K) is the active holo-SCNase. P15K is likely to promote the functional expression of SCNase probably by assisting the incorporation of cobalt ion

Fast and effective mitochondrial delivery of omega-Rhodamine-B-polysulfobetaine-PEG copolymers

Mitochondrial targeting and entry, two crucial steps in fighting severe diseases resulting from mitochondria dysfunction, pose important challenges in current nanomedicine. Cell-penetrating peptides or targeting groups, such as Rhodamine-B (Rho), are known to localize in mitochondria, but little is known on how to enhance their effectiveness through structural properties of polymeric carriers. To address this issue, we prepared 8 copolymers of 3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate and poly(ethyleneglycol) methacrylate, p(DMAPS-ran-PEGMA) (molecular weight, 18.0 <M-n <74.0 kg/mol) with two different endgroups. We labeled them with Rho groups attached along the chain or on one of the two endgroups (alpha or omega). From studies by flow cytometry and confocal fluorescence microscopy of the copolymers internalization in HeLa cells in the absence and presence of pharmacological inhibitors, we established that the polymers cross the cell membrane foremost by translocation and also by endocytosis, primarily clathrin-dependent endocytosis. The most effective mitochondrial entry was achieved by copolymers of M-n <30.0 kg/mol, lightly grafted with PEG chains (<5 mol %) labeled with Rho in the omega-position. Our findings may be generalized to the uptake and mitochondrial targeting of prodrugs and imaging agents with a similar polymeric scaffold.Peer reviewe

Periductal Induction of High Endothelial Venule-Like Vessels in Type 1 Autoimmune Pancreatitis

信州大学博士（医学）・学位論文・平成24年3月31日授与（甲第946号）・丸山 雅史This is a non-final version of an article published in final form in PANCREAS. 42(1):53-59 (2013).Objectives: Type 1 autoimmune pancreatitis (AIP) is histologically characterized by dense lymphoplasmacytic infiltration and marked storiform fibrosis, manifestations associated with pancreatic ducts. Such periductal lymphocyte recruitment is thought to be elicited by dysregulation of mechanisms governing physiological lymphocyte homing. The present study was undertaken to determine whether vascular addressins including peripheral lymph node addressin and mucosal addressin cell adhesion molecule 1 (MAdCAM-1) play a role in type 1 AIP histogenesis. Methods: Tissue sections of type 1 AIP and tumor-associated non-AIP chronic pancreatitis, as well as normal pancreas, were subjected to immunohistochemical analysis using vascular addressin-related antibodies. Results: The number of periductal mouse endothelial cell antigen 79-positive high endothelial venule (HEV)-like vessels was increased in type 1 AIP relative to that seen in non-AIP chronic pancreatitis, whereas the number of MAdCAM-1-positive HEV-like vessels did not differ between the 2 conditions. Mouse endothelial cell antigen 79 antigens are expressed on duct-forming epithelial cells not only in pancreas but also in salivary glands, which often harbor extrapancreatic lesions in type 1 AIP. Conclusions: Type 1 AIP can be characterized by periductal induction of MECA-79-positive HEV-like vessels. MECA-79-positive 6-sulfo sialyl Lewis X-related carbohydrate antigens expressed on duct-forming epithelial cells could be associated with type 1 AIP pathogenesis.ArticlePANCREAS. 42(1):53-59 (2013)journal articl

健常児・者におけるVictoria版Stroop Testの年齢による変化の検討

Victoria版Stroop Testにおける課題達成所要時間の年齢による変化について検討し、併せて各年齢群別標準値を得ることを目的とした。5歳1ヶ月から49歳0ヶ月の健常児・者193名を対象に、黒色で印刷された文字の色を読む（Word Reading:WR）課題、丸型カラーバッチの色名を言う（Color Naming:CN）課題、文字と印刷された色が異なる（Incongruent Color Naming:ICN）課題を行い、ICN課題達成所要時間に対するCN課題達成所要時間の差（以下ICN-CN）と比（以下ICN／CN）について年齢を説明変数とする単回帰分析を行った。その結果、全てにおいて年齢による有意な変化が見られ、成績が最良となる年齢は、WR課題において29.7歳、CN課題において29.0歳、ICN課題において30.2歳、ICN-CNにおいて31.0歳、ICN／CNにおいて34.5歳であることが明らかになった。また、各課題達成所要時間の差異についての一要因の分散分析を行った結果、有意差（F（2,576）＝179.312,p<.001）が認められた。多重比較（Turkey HSD)の結果、各課題間に有意差（WR課題とCN課題：p<.01、WR課題とICN課題：p<.001、CN課題とICN課題：p<.001）が認められ、WR課題、CN課題、ICN課題の順に有意な遅延を示した

The Stroop effect for Attention Deficit/Hyperactivity Disorder and Pervasive Developmental Disorder

注意欠陥/多動性障害（Attention Deficit/Hyperactivity Disorder ; AD/HD）および広汎性発達障害（Pervasive Developmental Disorder ; PDD)における干渉効果を検討することを目的とし、AD/HD群21名、PDD群23名、対照群101名を対象にストループテストを行い、Word Reading (WR)課題、Color Naming (CN)課題、Incongruent Color Naming (ICN)課題について評価した。対照群から得られた成績に95％の信頼区間を設け、AD/HD群およびPDD群の成績と比較した結果、AD/HD群においては大多数の症例が信頼区間の範囲内の成績を示した。一方、PDD群ではICN課題において23例中2例、ICN-CNにおいて23例中4例、ICN／CNにおいて23例中4例が95％信頼区間外の成績を示した。To clarify the interference effect in attention deficit/hyperactivity disorder (AD/HD) and pervasive developmental disorder (PDD), the Stroop test was performed with 21 children with AD/HD, 23 children with PDD and 101 normal subjects. Word reading, color naming (CN) and incongruent color naming (ICN) were measured, then, such indices as ICN-CN and ICN/CN as well as ICN scores were evaluated. Results obtained from children with AD/HD and PDD were compared with those from normal subjects applying the confidence interval of 95%. Most of the children with AD/HD were plotted within the range of 95% confidence interval. As for the PDD, 2 of 23 in ICN, 4 of 23 in ICN-CN and ICN/CN were plotted out of the 95% confidence interval. Further work on the characterization of the phenotype of PDD plotted out of the 95% confidence interval may aid in extending the clinical application of this test

Two Cases of Multiple Carcinoid Tumors and Gastric Enterochromaffin-like Cell Hyperplasia, Dysplasia and Neoplasia in Type A Gastritis

We describe two cases of multiple carcinoids and hyperplasia, dysplasia and neoplasia of enterochromaffin-like (ECL) cells associated with atrophic gastritis type A in the stomach. Multiple polypoid lesions measuring 1 cm showed upper gastroendoscopic features. They were all found in the upper body of the stomach. All polypoid lesions with carcinoid foci were observed from the deeper layers of the propria mucosa to the submucosa and were surrounded by ECL cells. In one case, the serum gastrin level which was as high as 1700 pg/mi, returned to normal range (17 pg/ml) after gastrectomy. It is suggested that longstanding hypergastrinemia may have played a causative role in the development of multiple gastric carcinoid tumors. A total gastrectomy was considered essential for treatment of aggressive multiple carcinoid tumors with hypergastrinemia