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Shinsuke Nomura

Publications and source records attributed to Shinsuke Nomura.

7 recordsLinked to original sources
PubMed2006

Intercellular localization of occludins and ZO-1 as a solute transport barrier of the mesothelial monolayer.

A hyperpermeable state has been observed in patients on long-term peritoneal dialysis. To understand the causes of the structural or functional changes and the progression of the fibrotic process, it is important to determine which region of the peritoneum exhibits these changes. The objectives of this study were to determine the solute permeability associated with cell-cell adhesion of human peritoneal mesothelial cells (HPMCs), to study the relationship between solute permeability and localizations of tight junction-associated proteins (TJPs: occludins and ZO-1), and to assess the effect of exogenous H2O2 supplementation. HPMCs were cultured on a Transwell until the transmesothelial electrical resistance (TER) reached a plateau. Solute permeation tests were conducted using fluorescein isothiocyanate - labeled dextran (molecular weight: 4, 10, 70, and 150 kDa) to calculate the solute permeability coefficient (SPC). Localization of TJPs was observed by a confocal laser scanning microscope after immunofluorescent staining. TER levels increased steadily, beginning at 97.5 +/- 0.7 ohms.cm2 and leveling off at 128 +/- 3.6 ohms.cm2 (n = 4). This was accompanied by the confluence of cells and the appearance of localized TJPs. SPC levels of the HPMC monolayer on the Transwell were reduced compared to those of the Transwell itself, indicating that the HPMC monolayer provided resistance against solute permeation. Exogenous H2O2 supplementation revealed an increased permeability accompanied with delocalization of TJPs, particularly occludins. The delocalization of occludins and ZO-1 at the intercellular space led to a decrease in intercellular binding capacity and thus triggered an increase in the solute permeability.

Cells, Cultured↗
PubMed2005

Identification of a novel amino acid deletion mutation and a very rare single nucleotide variant in a Japanese family with type I antithrombin deficiency.

We studied a Japanese family with type I antithrombin (AT) deficiency and identified a novel in-frame deletion mutation (-ATG at nucleotide position of 2771-2773) in the AT gene, which predicted loss of a methionine (Met) at amino acid number of 103. In addition, we found a single base replacement of G to A at nucleotide position of 67 (4 base upstream to the initial codon) in the mutant allele. Since the G67A substitution in the AT gene was very rare, this family was the second case, in which the nucleotide change was transmitted. To elucidate the mechanism of AT deficiency, we transiently expressed wild type and the mutant AT (DeltaM103) in HuH-7 human hepatoma cells and performed pulse-chase studies. The experiments revealed that the mutant AT (DeltaM103) hardly secreted into the medium and underwent partial intracellular degradation. In addition, we performed luciferase reporter assay to examine the effect of G67A substitution on the AT gene expression, and found that the substitution did not reduce the luciferase activity. These results suggested that secretion defect and intracellular degradation of the variant molecule with the deletion of Met 103 were responsible for AT deficiency in this family.

Adult↗
PubMed2004

[Successful treatment of allergic purpura nephritis associated with thrombotic microangiopathy using plasma exchange: a case report].

A 73-year-old man, who had an allergy to shellfish, was admitted to our hospital because of proteinuria, hematuria, purpura and extremity edema after eating oysters. Laboratory data on admission were proteinuria 2.0 g/day, hematuria 3+, serum creatinine (Cr) 1.2 mg/dl, total protein 6.3 g/dl, and albumin 3.1 g/dl. He presented a high fever with neutrophilia and rapid deterioration of renal function after admission. Based on the skin biopsy, we made a diagnosis of leukocytoclastic vasculitis with IgA deposition. Oral prednisolone (40 mg/day) following drip intravenous methylprednisolone (500 mg/day, 3 days) was administered. However, renal function and urinary findings showed no sign of improvement. In the first renal biopsy, although there were no crescentic formations, most of the glomeruli showed thrombotic microangiopathy and endocapillary proliferation with IgA deposition and electron dense deposits. Therefore, a plasma exchange was performed resulting in an improvement of the renal function. The serum Cr. level was reduced from 2.7 to 0.8 mg/dl and proteinuria from 3.7 to 0.1 g/day. In the second biopsy, the electron dense deposits with an IgA deposition had disappeared. These findings suggested that plasma exchange was effective in leading remission in a case of allergic purpura nephritis associated with thrombotic microangiopathy.

Aged↗
PubMed2003

Immunohistochemical diagnosis of Alport's syndrome in paraffin-embedded renal sections: antigen retrieval with autoclave heating.

Alport's syndrome (AS) is a hereditary renal disease caused by mutations in the genes encoding collagen type IV. Immunohistochemical analysis of the alpha chains of collagen type IV has been found to be useful for the diagnosis of this disease. The monoclonal antibodies (mAbs) generated by us recognize alpha 1(IV) through alpha 6(IV) chains of collagen type IV on fresh-frozen sections but not on paraffin-embedded sections. Antigen retrieval by autoclave heating has been found to restore the epitopes recognized by the mAbs; however the heating conditions had not been well established. In this study, the heating conditions were carefully examined using renal sections obtained from AS and non-AS patients. The heating was performed in an autoclave, at 105 degrees -127 degrees C for 6-8 min. During the heating, the sections were immersed in 0.2 N HCl solution (pH 0.9). Then, the mAbs were applied for 30 min, and the bound mAbs were detected using the LSAB kit. The optimal temperature for the antigen retrieval varied among specimens, and was dependent on the type of basement membrane examined. Thus, it was considered that heating at two or three different temperatures could be helpful for the precise diagnosis of AS. Adopting the antigen retrieval method could extend the possibility of immunohistochemical diagnosis of AS to cases without using fresh-frozen sections.

Aged↗
PubMed2003

Management of oral surgery in patients with hereditary or acquired angioedemas: review and case report.

Angioedemas are a rare but significant event in simple oral surgery because they can cause an acute life-threatening laryngeal edema. We report a case of a tooth extraction in a patient with hereditary angioedema, for which the C1-inhibitor (C1-INH) concentration administered effectively controlled edema during and after extraction. We also review case reports of oral surgery management in patients with hereditary and acquired angioedemas. In 2 of 36 cases, laryngeal edema occurred after teeth extraction. One was considered to be a type 2 acquired angioedema, which tolerates replacement therapy with fresh frozen plasma. The other case was managed only with danazol, and it was suggested that this was on occasion insufficient. Safety of oral surgery on patients with angioedema depends on the type of angioedema and the availability of C1-INH concentration. An exact diagnosis of the type of angioedema is needed to know the effect of replacement therapy with C1-INH.

Angioedema↗