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T Tsuji

Publications and source records attributed to T Tsuji.

At least 37 records · Page 2Linked to original sources
PubMed2002

Mucosal immunoadjuvant activity of the low toxic recombinant Escherichia coli heat-labile enterotoxin produced by Bacillus brevis for the bacterial subunit or component vaccine in pigs and cattle.

A gene encoding the mature Escherichia coli heat-labile enterotoxin (LT) lacking the nick site in the A subunit by deleting tripeptides was introduced in a vector pNH301 and expressed extracellularly as mutant molecule of holotoxin at high levels in Bacilus brevis HPD31-S5 of the host bacterium. The mucosal adjuvant activities of the produced mutant LT (mLT) preparation were studied in pigs and cattle. Intranasal immunization of pigs with the recombinant subunit vaccine of Erysipelothrix rhusiopathiae or the component vaccine of Bordetella bronchiseptica mixed with the mLT resulted in a substantial enhancement of both mucosal and serum-specific antibody levels. The immunized pigs were also protected when challenge-exposed intradermally with a highly virulent E. rhusiopathiae strain or challenge-exposed intranasally with a highly virulent strain of B. bronchiseptica. The mLT intranasally administered with recombinant intimin (an outer membrane adhesin) of E. coli O157:H7 also induced an elevation of IgA-specific antibody in the nasal secretion and saliva of calves as well as an elevation of IgG1-specific antibody level against the intimin in the sera and colostrum of cows. The three kinds tested protein antigens were poorly immunogenic when antigen administered intranasally alone. The mLT intranasally administered at a higher effective dose did not induce local adverse reactions or diarrhea in pigs and cattle. The present study demonstrates that the recombinant mLT produced using the B. brevis expression system might represent promising immunoadjuvants for the potential application of intranasal vaccines directed against infectious diseases in pigs and cattle.

Adjuvants, Immunologic↗
PubMed2002

Proteomic profiling and neurodegeneration in Alzheimer's disease.

Quantitative proteome analysis of Alzheimer's disease (AD) brains was performed using 2-D gels to identify disease specific changes in protein expression. The task of characterizing the proteome and its components is now practically achievable because of the development and integration of four important tools: protein, EST, and complete genome sequence databases, mass spectrometry, matching software for protein sequences and protein separation technology. Mass spectrometry (MS) instrumentation has undergone a tremendous change over the past decade, culminating in the development of highly sensitive, robust instruments that can reliably analyze biomolecules, particularly proteins and peptides; we identified 35 proteins from over 100 protein spots on a 2-D gel. Using this current technology, protein-expression profiling, which is actually a specialized form of mining, is an important principal application of proteomics. The information obtained has tremendous potential as a means of determining the pathogenesis, and detecting disease markers and potential targets for drug therapy in AD.

Aged↗
PubMed2002

High expression of transgenes mediated by hybrid retroviral vectors in hepatocytes: comparison of promoters from murine retroviruses in vitro and in vivo.

To achieve high transgene expression in the liver, we have compared the reporter gene expression among various murine retroviral long terminal repeats (LTRs) or leader sequences in vitro. Transient reporter gene expression assays revealed the highest gene expression by the polycythemic strain of spleen focus-forming virus (SFFVp) LTR in differentiated hepatocellular carcinoma cell lines, HuH-7 and PLC/PRF/5. However, remarkable difference was not observed among LTRs in other types of human liver tumor cell lines. Essentially the same results were obtained by infecting these cells with a series of retroviral vectors. Repression of transgene expression was observed by the leader sequences from Moloney murine leukemia virus (MoMLV), but not from mouse embryonic stem cell virus (MESV). Strengths of the promoters were further compared in murine hepatocytes in vivo. Although the proportions of genomic integration were almost the same, higher gene expression was observed by the FMEV-type vector, which contained the SFFVp LTR and the MESV leader, in comparison with that by the MoMLV-based vector. Thus, FMEV-type vectors may represent a novel type of vectors for human gene therapy with hepatocytes.

Animals↗
PubMed2002

Surgical technique and outcome of gasless video endoscopic transanal rectal tumour excision.

BACKGROUND: Transanal endoscopic microsurgery (TEM) is unpopular because of its high cost and most surgeons' unfamiliarity with microscopic surgery. This report describes an experience with a modification of TEM, gasless video endoscopic transanal rectal tumour excision (gasless VTEM), which incorporates a standard laparoscopic video camera and requires no carbon dioxide insufflation system. METHODS: One hundred and one patients with 105 rectal tumours underwent gasless VTEM between 1993 and 2000. RESULTS: Histological examination revealed 18 adenomas, 75 carcinomas (Tis, 47; T1, 23; T2, five), 11 carcinoid tumours and one lymphoma. The median height above the dentate line and maximum tumour diameter was 5.0 (range 2-14) cm and 2.0 (range 0.4-8.0) cm respectively. The peritoneal cavity was opened intraoperatively in two patients. The median operating time was 53 (range 15-202) min. Bleeding, suture dehiscence and transient incontinence developed after operation in four patients. There was no operative death. Median hospital stay was 5 (range 1-21) days. Eleven patients with T1/T2 staging underwent subsequent radical resection. The median duration of follow-up was 52.3 months. One patient with a carcinoma developed a recurrence. CONCLUSION: Gasless VTEM is a feasible, safe and minimally invasive procedure for the treatment of selected rectal adenomas and early carcinomas. The suggested modifications may make the procedure more widely available.

Adenocarcinoma↗
PubMed2002

Enhanced expression of decay-accelerating factor and CD59/homologous restriction factor 20 in intestinal metaplasia, gastric adenomas and intestinal-type gastric carcinomas but not in diffuse-type carcinomas.

AIMS: Variable expression of the complement regulatory proteins, decay-accelerating factor, CD59/homologous restriction factor 20 (HRF20) and membrane cofactor protein has been shown in human gastrointestinal malignancies, but their expression in gastric cancer has not been fully described. Thus, we immunohistochemically defined the distribution of these proteins in human normal gastric mucosa, intestinal metaplasia, adenomas and gastric cancers. METHODS AND RESULTS: Gastric tissues were obtained by endoscopic biopsy or surgical resection and stained with mouse monoclonal antibodies to decay-accelerating factor, CD59/HRF20, and membrane cofactor protein. In the normal gastric mucosa, membrane cofactor protein was diffusely stained on the basolateral surface of epithelial cells, whereas the expression of decay-accelerating factor and CD59/HRF20 was inconspicuous. In intestinal metaplasia, adenoma and intestinal-type gastric carcinoma cells, decay-accelerating factor and HRF20 were intensely stained on the apical surface; membrane cofactor protein retained its location on the basolateral surface. In diffuse-type gastric carcinomas, the expression of decay-accelerating factor, CD59/HRF20 was lost, but membrane cofactor protein was present on the tumour cell surface. CONCLUSIONS: These findings suggest that membrane cofactor protein plays a primary role in the regulation of complement activation in normal and neoplastic gastric cells and that the expression pattern of the complement regulatory proteins is closely related to gastric carcinoma development.

Adenoma↗
PubMed2002

Ultraviolet B induces mast cell apoptosis: a hypothetical mechanism of ultraviolet B treatment for uraemic pruritus.

The pathogenesis of uraemic pruritus is unclear, although there is some evidence that an increased number of skin-infiltrating mast cells may play a role. Ultraviolet B reduces itchy sensation of uraemic patients by leading to depletion of cutaneous mast cells. This study presents data that both broad-band and narrow-band ultraviolet B irradiation are able to induce apoptosis in transformed mast cells (murine mastocytoma cell line P815) in a dose-dependent manner at a time point of 24 hours. The positive apoptotic rates were as follows: sham-exposed cells (controls) -- 13.3% +/- 0.6%; with broad-band ultraviolet B irradiation -24.5% +/- 1.1% with 10mJ/cm(2), 57.9% +/- 4.6% with 20mJ/cm(2) and 70.9% +/- 4.5% with 30mJ/cm(2); with narrow-band ultraviolet B irradiation -- 29.6% +/- 2.3% with 100mJ/cm(2), 57.3% +/- 4.1% with 200mJ/cm(2) and 81.5% +/- 1.9% with 300mJ/cm(2). The difference between the number of apoptotic cells in all groups of ultraviolet B-irradiated cells and sham-exposed cells was highly significant (P<0.001). Based on these findings, it is hypothesized that ultraviolet B induced mast cell apoptosis could be an important factor in phototherapy for the diseases dependent on increased number of cutaneous mast cells, including uraemic pruritus.

Animals↗
PubMed2002

Laparoscopic features of primary biliary cirrhosis in AMA-positive and AMA-negative patients.

BACKGROUND AND STUDY AIMS: Antimitochondrial antibody (AMA)-negative primary biliary cirrhosis (PBC) has been difficult to diagnose. Laparoscopic features of AMA-negative PBC were evaluated in comparison with those of AMA-positive PBC and autoimmune hepatitis. PATIENTS AND METHODS: 71 patients who fulfilled the diagnostic criteria for PBC were enrolled in the study; 48 were AMA-positive and 23 were AMA-negative. As a disease control, 46 autoimmune hepatitis patients were included. Both the frequency and specificity of each laparoscopic finding were evaluated. A laparoscopic scoring system was introduced, which used, common and uncommon laparoscopic findings, and was evaluated for the diagnosis of AMA-negative PBC. RESULTS: The characteristic laparoscopic findings for AMA-positive PBC were yellowish-white marking (92 %), dark-brown discoloration (73 %), gentle undulation (67 %), reddish patch (38 %), and yellowish-white nodules (32 %). On the other hand, laparoscopic findings such as trench-like depression, reddish markings, and wide and small depressions were uncommon in PBC compared with autoimmune hepatitis. The frequencies of characteristic and uncommon laparoscopic findings did not differ statistically between AMA-positive and AMA-negative PBC, but were different between AMA-positive or AMA-negative PBC and autoimmune hepatitis. Scores based on common and uncommon laparoscopic findings were 5.5 +/- 1.5 (mean +/- SD) in AMA-positive PBC, 5.6 +/- 2.0 in AMA-negative PBC, and - 0.30 +/- 0.5 in autoimmune hepatitis. CONCLUSION: The laparoscopic findings in AMA-negative PBC did not differ from those of AMA-positive PBC. A laparoscopic scoring system may be helpful in the diagnosis of AMA-negative PBC.

Adult↗
PubMed2002

Regulation of circulating immune complexes by complement receptor type 1 on erythrocytes in chronic viral liver diseases.

BACKGROUND AND AIM: Complement receptor type 1 (CR1) is a transmembrane protein, and human erythrocyte CR1 (E-CR1) is involved in the transport of circulating immune complexes (IC) from the circulation to the reticuloendothelial system, including the liver and spleen. In chronic viral hepatitis, increased levels of IC containing viral particles and an association with various extrahepatic manifestations have been reported. However, regulatory mechanisms for IC levels are not fully understood. PATIENTS/SUBJECTS AND METHODS: We analysed IC, E-CR1, and quantitative polymorphism of the CR1 gene in 149 patients with chronic viral liver diseases and in 64 normal blood donors using an enzyme linked immunosorbent assay, radioimmunoassay, and polymerase chain reaction-restriction fragment length polymorphism, respectively. We also analysed the effect of CR1 gene polymorphism on IC binding to E-CR1 using molecular methods. RESULTS: E-CR1 levels in patients with chronic hepatitis and chronic viral liver diseases as a whole correlated inversely with increased levels of IC. Moreover, significantly high levels of IC were observed in patients with chronic hepatitis C (CH-C) who were homozygous for the E-CR1 low density allele. We also found low levels of E-CR1 in liver cirrhosis and CH-C but not in CH-B. Low levels of E-CR1 in CH-C were observed, even after considering the polymorphism of the CR1 gene. Finally, we demonstrated CR1 gene polymorphism dependent binding of hepatitis virus containing IC. CONCLUSIONS: Our results emphasise the important role of E-CR1 in clearance of IC from the circulation and the acquired, rather than inherited, decrease in E-CR1 in chronic viral liver diseases, especially of type C.

Adult↗
PubMed2002

Evaluation of sialyl Lewis(a), sialyl Lewis(x), and sialyl Tn antigens expression levels as predictors of recurrence after curative surgery in node-negative colorectal cancer patients.

This study aimed to determine whether sialyl Lewis(a) (Le(a)), sialyl Lewis(x )(Le(x)), or sialyl Tn antigen expression could identify a subset of node-negative colorectal cancer patients that are at high risk for recurrence after curative surgery. Tumor tissue samples from 90 patients with node-negative colorectal cancer, who had undergone surgical resection, were analyzed immunohistochemically for the expression of each antigen. Patients were classified as having low or high antigen expression depending on whether more or less than 40% of the field showed positive staining. The main outcome measure for each variable was disease-free interval. Sialyl Le(a), sialyl Le(x), and sialyl Tn antigens were expressed in 53 (58.9%), 41 (45.6%), and 34 (37.8%) carcinomas, respectively. The median follow-up was 83.5 months. Patients with high sialyl Le(x) expression had shorter disease-free intervals than those with low sialyl Le(x) expression (P = 0.0041); the expression of sialyl Le(a) or sialyl Tn antigens did not show a significant relationship with disease-free survival. Cox's regression analysis revealed that sialyl Le(x) expression was an independent predictor for disease-free survival, separate from T factor or tumor location. High sialyl Le(x) expression may be useful in identifying a subset of node-negative colorectal cancer patients who are at high risk for recurrence.

Adult↗
PubMed2002

Increased expression of sialyl Lewis(x) antigen in penetrating growth type A early gastric cancer.

Early gastric cancer can be divided morphologically into two categories, penetrating growth type-A (Pen-A type) and other growth types (non-Pen-A types). Sialyl Lewis(x) antigen has been demonstrated to play an important role in tumor metastasis by serving as a functional ligand in the cell adhesion system. The aim of this study is to ascertain whether or not sialyl Le(x) antigen expression correlates with tumor growth patterns of early gastric carcinoma. An immunohistochemical assay was performed using monoclonal antibody CSLEX1 in 12 Pen-A type and 79 non-Pen-A type cancers. Scoring was based on the percentage of immunoreactive cells: negative, low expression (< or = 25%), and high expression (> 25%). Lymph node metastasis was found more frequently in Pen-A type than non-Pen-A type cancers (P=0.0004). Furthermore, sialyl Le(x) antigen high expression was detected more often in Pen-A type cancers (7 out of 12; 58.3%) than non-Pen-A type cancers (13 out of 79; 16.5%) (P=0.0036). Multivariate logistic regression analysis showed that these variables are related independently to the Pen-A type and the non-Pen-A type tumor growth patterns. These data suggest that the difference in sialyl Le(x) antigen expression between the Pen-A type and non-Pen-A type tumor growth patterns of early gastric cancer may, at least partially, reflect different biological behavior during tumor progression.

Adenocarcinoma↗
PubMed2001

Preparation, structure, and amphoteric redox properties of p-phenylenediamine-type dyes fused with a chalcogenadiazole unit.

4,7-Bis(dialkylamino)benzo[c][1,2,5]chalcogenadiazoles are a novel class of organic dyes that undergo reversible two-stage one-electron oxidation as well as one-electron reduction. They exhibit absorption maxima in the long-wavelength region, which are assigned as intramolecular charge transfer bands from the phenylenediamine moiety to the electron-accepting heterocycle. Their redox properties as well as molecular and crystal structures are affected by the alkyl substituents on the amino nitrogen and/or by the chalcogen atom (O, S, Se) in the heterocycle.

Journal Article↗
PubMed2001

Antiproliferative activity of REIC/Dkk-3 and its significant down-regulation in non-small-cell lung carcinomas.

We recently reported the cloning of the REIC/Dkk-3 gene, whose expression was shown to be down-regulated in many human immortalized and tumor-derived cell lines [T. Tsuji et al. (2000) Biochem. Biophys. Res. Commun. 268, 20-24]. In the present study, we demonstrated that expression of the exogenous REIC/Dkk-3 gene in tumor cells inhibited cell growth. Furthermore, the level of REIC/Dkk-3 mRNA in normal human cells was lowest in the late G(1) phase during the cell cycle. Then we found that the expression of REIC/Dkk-3 was significantly down-regulated in surgically resected non-small-cell lung carcinomas. We determined the REIC/Dkk-3 locus on chromosome 11p15, where loss of heterozygosity has frequently been observed in human tumors. These findings indicate that REIC/Dkk-3 may function as a tumor suppressor.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V(1).

OBJECTIVES: We sought to determine the electrocardiographic (ECG) features associated with acute left main coronary artery (LMCA) obstruction. BACKGROUND: Prediction of LMCA obstruction is important with regard to selecting the appropriate treatment strategy, because acute LMCA obstruction usually causes severe hemodynamic deterioration, resulting in a less favorable prognosis. METHODS: We studied the admission 12-lead ECGs in 16 consecutive patients with acute LMCA obstruction (LMCA group), 46 patients with acute left anterior descending coronary artery (LAD) obstruction (LAD group) and 24 patients with acute right coronary artery (RCA) obstruction (RCA group). RESULTS: Lead aVR ST segment elevation (>0.05 mV) occurred with a significantly higher incidence in the LMCA group (88% [14/16]) than in the LAD (43% [20/46]) or RCA (8% [2/24]) groups. Lead aVR ST segment elevation was significantly higher in the LMCA group (0.16 +/- 0.13 mV) than in the LAD group (0.04 +/- 0.10 mV). Lead V(1) ST segment elevation was lower in the LMCA group (0.00 +/- 0.21 mV) than in the LAD group (0.14 +/- 0.11 mV). The finding of lead aVR ST segment elevation greater than or equal to lead V(1) ST segment elevation distinguished the LMCA group from the LAD group, with 81% sensitivity, 80% specificity and 81% accuracy. A ST segment shift in lead aVR and the inferior leads distinguished the LMCA group from the RCA group. In acute LMCA obstruction, death occurred more frequently in patients with higher ST segment elevation in lead aVR than in those with less severe elevation. CONCLUSIONS: Lead aVR ST segment elevation with less ST segment elevation in lead V(1) is an important predictor of acute LMCA obstruction. In acute LMCA obstruction, lead aVR ST segment elevation also contributes to predicting a patient's clinical outcome.

Acute Disease↗
PubMed2001

Relationship between plasma level of cardiotrophin-1 and left ventricular mass index in patients with dilated cardiomyopathy.

OBJECTIVES: The study evaluated the relationship between plasma cardiotrophin-1 (CT-1) concentration and left ventricular (LV) mass in dilated cardiomyopathy (DCM) patients with congestive heart failure (CHF). BACKGROUND: Cardiotrophin-1 is a newly identified member of the interleukin-6 (IL-6) family of cytokines and one of the endogenous ligands for gp130 signaling pathways in the heart, and it has potent hypertrophic and survival effects on cardiac myocytes. However, the clinical significance of CT-1 is poorly understood. METHODS: We measured the plasma CT-1 level in 51 consecutive patients with DCM. Patients were classified into two groups: small LV mass index group and large LV mass index group, based on the median level of LV mass index. RESULTS: The plasma CT-1 level was increased in DCM patients with the severity of CHF and was significantly higher in the large LV mass group than in the small LV mass group, despite the absence of a difference in LV ejection fraction between the two groups. In addition, there was a significant positive correlation between the plasma CT-1 level and the LV mass index (r = 0.627, p < 0.0001). According to stepwise multivariate analyses among hemodynamic and neurohumoral factors, a high plasma CT-1 level showed an independent and significant positive relationship with a large LV mass index in patients with DCM. CONCLUSIONS: These results indicate that the plasma CT-1 level is increased in patients with DCM and is significantly correlated with the LV mass index, suggesting that CT-1 plays an important role in structural LV remodeling in patients with DCM.

Adolescent↗
PubMed2001

Random multi-recombinant PCR for the construction of combinatorial protein libraries.

Development of a new methodology to create protein libraries, which enable the exploration of global protein space, is an exciting challenge. In this study we have developed random multi-recombinant PCR (RM-PCR), which permits the shuffling of several DNA fragments without homologous sequences. In order to evaluate this methodology, we applied it to create two different combinatorial DNA libraries. For the construction of a 'random shuffling library', RM-PCR was used to shuffle six DNA fragments each encoding 25 amino acids; this affords many different fragment sequences whose every position has an equal probability to encode any of the six blocks. For the construction of the 'alternative splicing library', RM-PCR was used to perform different alternative splicings at the DNA level, which also yields different block sequences. DNA sequencing of the RM-PCR products in both libraries revealed that most of the sequences were quite different, and had a long open reading frame without a frame shift or stop codon. Furthermore, no distinct bias among blocks was observed. Here we describe how to use RM-PCR for the construction of combinatorial DNA libraries, which encode protein libraries that would be suitable for selection experiments in the global protein space.

Alternative Splicing↗
PubMed2001

Th1 cytokine-conditioned bone marrow-derived dendritic cells can bypass the requirement for Th functions during the generation of CD8+ CTL.

Bone marrow-derived dendritic cell (BMDC) subsets have distinct immunoregulatory functions. Th1 cytokine-induced BMDC (BMDC1), compared with Th2 cytokine-induced BMDC2, have superior activities for the differentiation and expansion of CTL. To evaluate the cellular interactions between dendritic cells and CD8+ T cells for the induction of CTL, BALB/c-derived BMDC subsets were cocultured with purified CD8+ T cells from C57BL/6 mice. Our results demonstrate that BMDC1 support the generation of allogeneic CD8+ CTL in the absence of CD4+ Th cells. In contrast, BMDC0 (GM-CSF- plus IL-3-induced BMDC) and BMDC2 failed to promote the differentiation of CD8+ CTL. Using Ab-blocking experiments and studies with gene knockout mice, IL-2 and LFA-1 are demonstrated to be critical for BMDC1-induced CTL differentiation. Unexpectedly, BMDC1 were able to induce CTL from CD8+ T cells isolated from IFN-gamma-/- and IFN-gamma receptor-/- mice. However, BMDC1 produced higher levels of IFN-beta than other BMDC subsets, and anti-IFN-beta mAb blocked BMDC1-dependent CTL generation. These results indicated an indispensable role of IFN-beta, but not IFN-gamma, during BMDC1-induced CTL differentiation. We conclude that Th1-cytokine-conditioned BMDC1 can bypass Th cell function for the differentiation of naive CD8+ T cells into CTL.

Animals↗
PubMed2001

Dual-mode electrochromism switched by proton transfer: dynamic redox properties of bis(diarylmethylenium)-type dyes.

Upon oxidative dimerization of pale yellow Ar2C=CHPh 1 (Ar = 4-Me2NC6H4), deep blue 1,4-dication 2(2+) was obtained as a stable salt, which was transformed into 1 by reductive C-C bond fission; deprotonation of 2(2+) gave intense yellow diene 3, which was interconvertible with violet dication 4(2+) by two-electron transfer, thus exhibiting two distinct modes of electrochromism before and after proton transfer.

Journal Article↗