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H Tsuji

Publications and source records attributed to H Tsuji.

At least 109 records · Page 6Linked to original sources
PubMed2000

Roles of the AGE-RAGE system in vascular injury in diabetes.

This study concerns whether advanced glycation endproducts (AGE) are related to microvascular derangement in diabetes, exemplified by pericyte loss and angiogenesis in retinopathy and by mesangial expansion in nephropathy. AGE caused a decrease in viable pericytes cultivated from bovine retina. On the other hand, AGE stimulated the growth and tube formation of human microvascular endothelial cells (EC), this being mediated by autocrine vascular endothelial growth factor. In AGE-exposed rat mesangial cells, type IV collagen synthesis was induced. Those AGE actions were dependent on a cell surface receptor for AGE (RAGE), because they were abolished by RAGE antisense or ribozyme. The AGE-RAGE system may thus participate in the development of diabetic microangiopathy. This proposition was supported by experiments with animal models; several indices characteristic of retinopathy were correlated with circulating AGE levels in OLETF rats. The predisposition to nephropathy was augmented in RAGE transgenic mice when they became diabetic.

Animals↗
PubMed2000

A hydrogen peroxide-forming NADH oxidase that functions as an alkyl hydroperoxide reductase in Amphibacillus xylanus.

The Amphibacillus xylanus NADH oxidase, which catalyzes the reduction of oxygen to hydrogen peroxide with beta-NADH, can also reduce hydrogen peroxide to water in the presence of free flavin adenine dinucleotide (FAD) or the small disulfide-containing Salmonella enterica AhpC protein. The enzyme has two disulfide bonds, Cys128-Cys131 and Cys337-Cys340, which can act as redox centers in addition to the enzyme-bound FAD (K. Ohnishi, Y. Niimura, M. Hidaka, H. Masaki, H. Suzuki, T. Uozumi, and T. Nishino, J. Biol. Chem. 270:5812-5817, 1995). The NADH-FAD reductase activity was directly dependent on the FAD concentration, with a second-order rate constant of approximately 2.0 x 10(6) M(-1) s(-1). Rapid-reaction studies showed that the reduction of free flavin occurred through enzyme-bound FAD, which was reduced by NADH. The peroxidase activity of NADH oxidase in the presence of FAD resulted from reduction of peroxide by free FADH(2) reduced via enzyme-bound FAD. This peroxidase activity was markedly decreased in the presence of oxygen, since the free FADH(2) is easily oxidized by oxygen, indicating that this enzyme system is unlikely to be functional in aerobic growing cells. The A. xylanus ahpC gene was cloned and overexpressed in Escherichia coli. When the NADH oxidase was coupled with A. xylanus AhpC, the peroxidase activity was not inhibited by oxygen. The V(max) values for hydrogen peroxide and cumene hydroperoxide reduction were both approximately 150 s(-1). The K(m) values for hydrogen peroxide and cumene hydroperoxide were too low to allow accurate determination of their values. Both AhpC and NADH oxidase were induced under aerobic conditions, a clear indication that these proteins are involved in the removal of peroxides under aerobic growing conditions.

Amino Acid Sequence↗
PubMed2000

Occurrence of IgE antibody-recognizing N-linked glycan moiety of a soybean allergen, Gly m Bd 28K.

BACKGROUND: It has been reported that N-linked glycan moieties of glycoproteins function as IgE-reactive determinants. Gly m Bd 28K, a soybean allergen, was a glycoprotein with glycan moieties, which are supposed to be the Man(3)GlcNAc(2) backbone with the beta1-->2 xylose and alpha1-->3 fucose branches. The purpose of the present study was to examine the IgE-binding ability of the glycan moiety of Gly m Bd 28K in the binding reaction with patients' sera. METHODS: A peptide containing the glycan moiety was prepared from Gly m Bd 28K by digestion with lysyl endopeptidase. The binding site of the glycan moiety was determined by amino acid sequence analyses. The glycan moiety of the allergen was characterized using anti-horseradish peroxidase antibody (anti-HRP) recognizing the N-linked glycan moieties of glycoproteins. The binding of patients' IgE antibodies with their glycan moiety was examined by an immunostaining technique using the glycopeptide and its deglycosylated peptide derived from Gly m Bd 28K. RESULTS: The binding site of the glycan moiety in Gly m Bd 28K was shown to be its Asn20 residue. Gly m Bd 28K did react with anti-HRP and the sera of soybean-sensitive patients, but the binding of IgE antibodies was inhibited by the preincubation with anti-HRP. Moreover, the glycopeptide also reacted with the sera of soybean-sensitive patients, but its deglycosylated peptide did not react with any IgE antibodies of patients' sera. CONCLUSIONS: The specific IgE antibodies recognizing the N-linked glycan moieties of Gly m Bd 28K and other glycoproteins with homologous glycan moieties occur in the sera of soybean-sensitive patients. It was indicated that the N-linked glycan moieties such as that of Gly m Bd 28K may be one of the common IgE-reactive determinants distributed in various plant food proteins.

Allergens↗
PubMed2000

Effects of bradykinin on prostaglandin I(2) synthesis in human vascular endothelial cells.

The effects of bradykinin on the regulatory mechanisms of prostacyclin synthesis in endothelial cells were investigated in association with intracellular Ca(2+) kinetics, cytosolic phospholipase A(2) (cPLA(2)) activity, and mRNA expression of cPLA(2) and prostaglandin H synthase (PGHS) isoforms. Bradykinin enhanced prostacyclin release from endothelial cells time-dependently, but pretreatment with EGTA H-7 or HOE 140 inhibited bradykinin-induced prostacyclin release. Bradykinin increased both the influx of extracellular Ca(2+) and Ca(2+) release from the intracellular Ca(2+) storage sites. These reactions occurred within 5 minutes after bradykinin stimulation. Within 15 minutes, bradykinin activated cPLA(2) to 1.3-fold the control level. The constitutive expressions of mRNA of cPLA(2), PGHS-1, and PGHS-2 was 87, 562, and 47 amol/microg RNA, respectively. With the stimulation of bradykinin, cPLA(2) mRNA increased to 746 amol/microg RNA in 15 minutes, PGHS-1 mRNA increased to 10 608 amol/microg RNA, and PGHS-2 mRNA increased to 22 400 amol/microg RNA in 180 minutes. Pretreatment with cycloheximide superinduced cPLA(2) and PGHS-2 mRNA expression but almost completely inhibited PGHS-1. Pretreatment with EGTA had effects similar to pretreatment with cycloheximide in the case of cPLA(2) and PGHS-1 but did not affect PGHS-2. These findings suggest that the elevation of cPLA(2) activity caused by the increase of intracellular Ca(2+) concentration is important in the early phase of bradykinin-induced prostacyclin synthesis and that the mechanisms regulating cPLA(2) are different from those regulating PGHS isoforms in endothelial cells.

Bradykinin↗
PubMed2000

Distribution of a major lysosomal membrane glycoprotein, LGP85/LIMP II, in rat tissues.

We previously identified and characterized a major lysosomal membrane glycoprotein, termed LGP85 (identical to LIMP II), in rat liver lysosomes. This study describes the distribution of the mRNA and protein of LGP85 in rat tissues. LGP85 protein and mRNA were detectable in all tissues when analyzed by Western and Northern blotting. The 4.2- and 2.2-kb transcripts of LGP85 were detected in all tissues. Liver and lung have the highest and lowest levels of LGP85 mRNA, respectively. A single protein band with an apparent molecular weight (Mr) of approximately 85000 was detected in each tissue. The specific protein content of LGP85 in spleen was markedly higher than in other tissues. LGP85 protein is distributed in the tissues independently of LGP85 mRNA. Furthermore, there was a less significant relationship between LGP85 protein and another lysosomal membrane glycoprotein, lamp-1, in the tissue distribution (a regression coefficient of 0.086), which suggests that LGP85 may function in vivo independently of lamp-1.

Animals↗
PubMed2000

Absence of linkage between radiosensitivity and the predisposing atp7b gene mutation for heritable hepatitis in the LEC rat.

The LEC rat is known to be a mutant strain that spontaneously develops heritable hepatitis due to copper accumulation, caused by mutation of the copper-transporting ATPase gene (Atp7b). Immunodeficiency and radiosensitivity have also been observed. Hayashi et al. extensively examined the radiosensitivity of the LEC rat and concluded that its hypersensitivity is controlled by a single autosomal gene. Furthermore, they suggested the possibility that it correlates to copper accumulation due to the Atp7b gene mutation, because ionizing radiation-induced hydroxyl radicals might act in concert with copper-induced hydroxyl radicals. In the present experiment, we analyzed linkage between radiosensitivity and the mutation responsible for hepatitis in F(1) animals of a cross with the F344 rat. Our results clearly demonstrated an absence of any significant association. In addition, partial dominance for radiosensitivity was observed, and radiosensitive (F(1) x LEC) backcross rats were twice as numerous as their radioresistant counterparts, suggesting the possibility of control by two or more recessive genes.

Adenosine Triphosphatases↗
PubMed2000

Multilocular pyogenic hepatic abscess complicating ascaris lumbricoides infestation.

A 74-year-old man was admitted to our hospital with frequent right flank pain. The multiple multilocular hepatic abscesses were revealed by computed tomography. Radiographs following a barium meal showed a linear filling defect in the ileum consistent with ascariasis. One day after treatment with pyrantel pamoate, an Ascaris was passed in the stool. The pyogenic hepatic abscesses gradually healed with both antibiotics and continuous drainage. After 2 months, he was discharged. In this case, the pyogenic hepatic abscesses were thus considered to have been caused by an inflammation which spread through the portal vein.

Aged↗
PubMed2000

Membranoproliferative glomerulonephritis and demyelinating neuropathy caused by type II mixed cryoglobulinemia associated with HCV infection.

Type II cryoglobulinemia is sometimes observed in patients with HCV infection. It is also well known that some cases with membranoproliferative glomerulonephritis (MPGN) possess cryoglobulinemia, which can induce neuropathy. We treated a 73-year-old woman with hepatitis C virus (HCV) who was admitted to our department because of proteinuria. She was diagnosed as MPGN according to renal biopsy. Her ankle jerk was absent with reduced touch sensation and vibration below the knees; sural nerve biopsy revealed demyelinating neuropathy. Administration of prednisolone resulted in improved proteinuria. Cryoglobulinemia associated with HCV infection seemed to induce MPGN and demyelinating neuropathy.

Aged↗
PubMed2000

Structural and immunochemical homologies between foxtail millet glutelin 60 kDa and starch granule-bound starch synthase proteins from rice, barley, corn and wheat grains.

Foxtail millet glutelin 60 kDa (MG60) was purified by preparative SDS-PAGE, and the N-terminal amino acid sequence was determined within 20 residues. The result demonstrated that the primary structure at N-terminal of MG60 was almost identical to those of the granule-bound starch synthase (GBSS) proteins from rice, barley, corn, wheat and potato. The existence of common epitopes among MG60 and GBSS proteins from these starch-storing cereals were corroborated by immunoblot analysis using antisera raised against MG60. These facts strongly suggest a close relationship between MG60-like glutelins and GBSS proteins.

Amino Acid Sequence↗
PubMed2000

Efficient extraction and some properties of storage proteins (prolamin and glutelin) in ancient rice cultivars.

Two typical storage proteins (prolamin and glutelin) in a total of 14 samples of ancient rice cultivars were examined for their accumulation in the endosperms during days after flowering (DAF), extraction efficiency with various solvents, and variations in polypeptide components or amino acid compositions. There was little difference in accumulation profiles between this and previous observations, in which glutelin appeared on 5-7 DAF and prolamin on 7-9 DAF. As for the extraction of prolamin and glutelin, it was most effectively attained by sequential usage of 55% propanol and 21% SDS. As a result of SDS-PAGE, prolamin and glutelin proved to be composed mainly of a single polypeptide with a molecular weight (MW) of 15 kDa and two subunits with MWs of 21 kDa (alpha) and 32 kDa (beta), respectively. A comparison between the ancient and modern rice cultivars revealed the same physicochemical properties in either case of prolamin or glutelin. Additionally, a good relationship was observed on the total protein and glutelin (but not prolamin) contents in the ancient rice cultivar.

Electrophoresis, Polyacrylamide Gel↗
PubMed2000

[Sinusotomy with intraoperative mitomycin C administration in selected eyes with advanced glaucomatous damage].

PURPOSE: To study the surgical outcome of sinusotomy with intra-operative mitomycin C administration (0.04%, 3 minutes) in a total of 17 selected glaucoma eyes from 14 patients with advanced glaucomatous damage. Selection criteria were 1. an eye with visual field defect threatening the central fixation, while the central visual acuity of the contralateral eye was already impaired; and/or 2. an aphakic or pseudophakic eye with advanced glaucomatous damage in a patient of advanced age. MATERIALS AND METHODS: Patients' age, preoperative mean deviation (Humphrey 30-2 program) and intraocular pressure (IOP) averaged 63.5 +/- 11.1 (mean +/- standard deviation) years, -18.6 +/- 6.7 (mean +/- standard deviation) dB, and 20.7 +/- 4.1 (mean +/- standard deviation) mmHg, respectively. RESULTS: No postoperative hypotony (< 5 mmHg) or deterioration of visual acuity equal to or more than 2 lines of Ishihara Visual Acuity Chart were encountered and the mean postoperative IOP ranged between 11 and 13 mmHg up to 18 months postoperatively with less medication than preoperatively. The success was defined as IOP < or = 15 mmHg without oral carbonic anhydrase inhibitors and with less medication than preoperatively. The life-table method analysis according to the above criteria yielded a success probability of 70.6 +/- 11.1 (mean +/- standard deviation) % (standard error) at 18 months postoperatively.

Adult↗
PubMed2000

[A case of adenoid cystic carcinoma of the trachea resected surgically after Nd-YAG laser therapy].

A case of primary tracheal tumor ablated by endoscopic Nd-YAG laser prior to tracheal sleeve resection was reported. A 53-year-old man had dry cough, bloody sputum and dyspnea. Bronchoscopic examination revealed polypoid tumor which located 2 cm below the vocal cords and obstructed the airway almost completely. After tumor vaporized by Nd-YAG laser, bronchoscopy type 200 could pass through the tracheal lumen and the length of the lesion was diagnosed within 4 cm. Biopsy specimen was confirmed adenoid cystic carcinoma. Cervical trachea was resected of six tracheal cartilage (first to sixth cartilage) combined with left thyroid lobe under collar incision and median sternotomy. The neck was fixed for ten days by tying the jaw to the anterior chest wall in order to reduce excessive tension to the anastomosis. Pathological examination revealed the tumor residual microscopically, 60 Gy of radiotherapy was conducted.

Carcinoma, Adenoid Cystic↗
PubMed2000

[The latest innovations in the operation of en-bloc resection on the frontal skull base].

We have organized skull base surgery teams with otolaryngologists, neurosurgeons and plastic surgeons since 1993 and managed frontal skull base malignancies by a combined transbasal and transfacial approach. However, in the maneuvers, several problems are yet to be solved in minimizing tumor recurrence and postoperative complications. We have recently developed a microscopic en-bloc resection method assisted by an endoscope, and VFOT flap (vascularized frontal outer table flap) for the reconstruction on the frontal skull base. The VFOT flap can be elevated simultaneously with bifrontal craniotomy. The pedicled calvarian bone is split, and the frontal outer table with the pericranium is placed on the frontal base defect caused by the tumor resections. Those procedures seem to be useful for skull base surgery, and easy to perform for neurosurgeons.

Adult↗