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Y Arimura

Publications and source records attributed to Y Arimura.

At least 19 recordsLinked to original sources
PubMed2003

The clinical and pathological features of peripheral neuropathy accompanied with HTLV-I associated myelopathy.

We describe the clinical and pathological studies in HTLV-I associated myelopathy (HAM)/tropical spastic paraparesis (TSP) patients with peripheral neuropathy as proven by sural nerve biopsy. Sural nerve pathology in HAM/TSP patients revealed that the most common type of pathologic change is a combination of both demyelination and remyelination and axonal degeneration and regeneration, and this change is modified by the complications. The pathologic changes were correlated with neither the duration of disease nor human T lymphotropic virus type I (HTLV-I) proviral load. This study suggests that peripheral nerves could be involved in HAM/TSP.

Aged↗
PubMed2001

Clinicopathologic and prognostic significance of matrilysin expression at the invasive front in human colorectal cancers.

Matrix metalloproteinases (MMPs) have been implicated in tumor progression. Matrilysin, one of the matrix metalloproteinases, is frequently overexpressed in gastrointestinal cancers. The aim of our study was to assess the validity of matrilysin as a prognostic marker of colorectal cancers. Matrilysin expression was immunohistochemically analyzed using formalin-fixed, paraffin-embedded specimens from 113 colorectal cancer patients who had undergone curative surgery. The lumenal surface of neoplastic glands in the superficial layer was apically stained, while the cytoplasm of cancer cells at the invasive front was diffusely stained for matrilysin. Sections with immunostaining signals in more than 30% of carcinoma cells at the invasive front, which were observed in 47 (42%) cases, were judged as being positive for matrilysin. Matrilysin positivity was significantly correlated with the depth of invasion, lymph node metastasis, lymphatic invasion, advanced Dukes' stage and poor outcome. Patients with matrilysin-positive cancer had a significantly shorter overall survival time than those with matrilysin-negative cancer. For patients with intermediate invasive tumor (T2 or T3), only matrilysin was a significant prognostic variable for predicting overall survival in multivariate analysis. Matrilysin expression at the invasive front could be an important marker, predicting an unfavorable prognosis after surgical treatment in patients with colorectal cancer.

Biomarkers, Tumor↗
PubMed2001

Expression of angiomodulin (tumor-derived adhesion factor/mac25) in invading tumor cells correlates with poor prognosis in human colorectal cancer.

Angiomodulin (tumor-derived adhesion factor/mac25/insulin-like growth factor binding protein-7), a cell-adhesive glycoprotein, is secreted by cancer cells and vascular endothelial cells. It may be involved in angiogenesis and modulation of the vascular functions necessary for tumor development. Although angiomodulin is expressed in colon cancer, there is limited information on it concerning cancer progression. In the present immunohistochemical study, we examined expression of angiomodulin in human colorectal cancer and its relationship with prognosis. A group of 89 surgically resected colorectal cancers was investigated immunohistochemically. In 37 cases (41.6%), angiomodulin was expressed in invading cancer cells. Early recurrence within 12 months after surgery was higher in patients with angiomodulin-expressing cancer than in those without (p < 0.05). The Kaplan-Meier life table revealed that patients with angiomodulin-positive tumor cells had a shorter survival time than those with negative cells (p < 0.01). The prognosis of patients with Dukes' C and angiomodulin-positive cells was apparently worse than that of patients with Dukes' D and angiomodulin-negative cells. Multivariate analysis with logistic regression indicated that only angiomodulin expression in cancer cells, lymph node metastasis and age remained significant prognostic variables for survival (p < 0.05). Angiomodulin showed correlations with poor prognosis, indicating that it may be a useful prognostic marker in patients with colorectal cancer.

Adult↗
PubMed2001

Opposing regulation of B cell receptor-induced activation of mitogen-activated protein kinases by CD45.

In this study, we examined the contribution made by CD45 to B cell antigen receptor (BCR)-induced activation of mitogen-activated protein kinase (MAPK) family members. We found that CD45 negatively regulated BCR-induced c-Jun NH(2)-terminal kinase (JNK) and p38 activation in immature WEHI-231 cells, whereas in mature BAL-17 cells, CD45 positively regulated JNK and p38 activation and negatively regulated extracellular signal-regulated kinase activity. Furthermore, cooperative action of JNK and p38 dictated BCR-induced inhibition of growth. Thus, CD45 appears to differentially regulate BCR-induced activation of MAPK members, and can exert opposing effects on JNK and p38 in different cellular milieu, controlling the B cell fate.

Animals↗
PubMed2001

Jejunal carcinoid tumor mimicking leiomyosarcoma: preoperative diagnosis by endoscopic biopsy.

Primary carcinoid tumor of the jejunum is rare, and is an unusual cause of massive gastrointestinal bleeding. A case of primary jejunal carcinoid tumor in a 39-year-old woman who presented with massive hematochezia is described. Both upper and lower gastrointestinal endoscopies showed no abnormalities. An abdominal computed tomographic scan, small-bowel barium contrast studies, and small-bowel endoscopy showed a subserosal mass, of 5 x 4 cm, with a cavity suggesting central necrosis, and a deep mucosal ulceration, located in the proximal jejunum. Although these clinical presentations were strongly suggestive of a leiomyosarcoma, histologic examination of biopsy samples obtained by enteroscopy confirmed the diagnosis of jejunal carcinoid tumor. The patient underwent radical jejunal resection and recovered uneventfully. In spite of the large size of the tumor, there was one solitary lymph node metastasis, but no evidence of liver metastases. This kind of jejunal carcinoid tumor, presenting with massive gastrointestinal bleeding and a subserosal bulky growth mimicking a leiomyosarcoma, has not been reported previously. Moreover, this is a rare case of a jejunal carcinoid which was diagnosed preoperatively by small bowel-endoscopic biopsy.

Adult↗
PubMed2001

Epstein-Barr virus-associated gastric cancer in a patient with dermatomyositis.

A 59-year-old man was admitted presenting systemic rash and muscle weakness. He was diagnosed to have dermatomyositis and a check was made for internal malignancy. Gastrointestinal endoscopy revealed a Borrmann type II tumor on the middle body of the stomach. Biopsy specimens showed a well differentiated adenocarcinoma, and total gastrectomy was performed. The final diagnosis was moderately differentiated adenocarcinoma invading into the proper muscular layer, with metastases to regional lymph nodes. Most of the neoplastic cells were shown to be positive for Epstein-Barr virus by means of EBV-encoded RNA in situ hybridization. The symptoms of dermatomyositis disappeared completely after surgery.

Adenocarcinoma↗
PubMed2001

[Anti-neutrophil cytoplasmic antibody--enzyme immunosorbent assay].

Enzyme immunosorbent assay(ELISA) is a very useful method to determine anti-neutrophil cytoplasmic antibody(ANCA), which is an important serological marker for pauci-immune type systemic vasculitis and necrotizing glomerulonephritis. A test was made using new myeloperoxidase(MPO)-ANCA ELISA(A), employing native MPO purified from the neutrophils in sputum as a liquid phase antigen. Furthermore, the ELISA(B) using MPO, composed of one large and one small subunit, was tested as solid phase antigen. The intra-assay and inter-assay CV of the new ELISA(A) were 3.92 to 6.75% and 5.0 to 8.1%, respectively. Close ANCA titer correlation was shown between the new MPO-ANCA ELISA(A) and the conventional ELISA, using native MPO from peripheral neutrophils as solid phase antigen. ELISA(B) showed low MPO-ANCA detection sensitivity compared to ELISA(A) and to conventional ELISA. ELISA using native MPO from neutrophils in sputum as liquid phase antigen is useful for MPO-ANCA detection. There might be an ANCA which recognizes only native form MPO.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2001

[Introduction and clinical evaluation of a new non-invasive cardiac output monitor (NICO) based on Fick partial CO2 rebreathing method].

A newly developed non-invasive monitor, NICO (Novametrix Medical Systems Inc.), measures cardiac output based on changes in respiratory CO2 concentration caused by a brief period of rebreathing. By applying modified form of the CO2 Fick principle, cardiac output is calculated. We determined the accuracy and precision of this technique (RBCO) by comparing it with continuous thermodilution technique (TDCCO) and pulse dye densitometry technique (PDD). The overall difference between RBCO and TDCCO(n = 46) was -0.21 +/- 1.43 (bias +/- 2 SD)l.min-1. On the other hand, the overall difference between RBCO and PDD (n = 53) was -0.1 +/- 2.04 (bias +/- 2 SD)l.min-1. The degree of accuracy of RBCO was thought to be the same as those of TDCCO and PDD. We expect that NICO will be a useful cardiac output monitor in any method of general anesthesia in which PA catheterization is difficult or not indicated.

Anesthesia, General↗
PubMed2001

[A case of IgA nephropathy associated with silicosis].

A 51-year-old male who had been working as a building wrecker for 20 years, was admitted to our hospital in June 1999 for proteinuria and hematuria examination. He started this work in 1978. Twelve years later, severe coughing and bloody sputum began and he was diagnosed as having silicosis in 1995. Urinalysis on admission showed proteinuria(294 mg/day), microhematuria(20-30/hpf), RBC cast and granular cast. High serum IgA(770 mg/dl) and high serum interleukin-6(IL-6) (3,280 pg/dl) were found. A renal biopsy showed mild mesangial matrix expansion and mesangial cell proliferation with IgA deposition, which was diagnosed as IgA nephropathy. Chest X-rays showed multiple small nodular lesions on both lung fields indicating silicosis. In Nov. 1999, he resigned from his job as a building wrecker because of increasing coughing and bloody sputum associated with body weight loss. Within 3 months after stopping this work, coughing and bloody sputum disappeared and the abnormal urinalysis findings returned to normal. Serum IgA and serum IL-6 data improved to 462 mg/dl and 2.5 pg/dl, respectively. It is suggested that silicon exposure might be related to the pathogenesis of IgA nephropathy in this patient.

Biomarkers↗
PubMed2001

[Two cases of visceral larva migrans due to Ascaris suum showing a migratory nodular shadow].

The number of cases of visceral larva migrans caused by the pig ascarid, Ascaris suum has recently been increasing. We have encountered two cases of visceral larva migrans due to A. suum with a nodular shadow on the chest radiograph and eosinophilia in the peripheral blood. Patient 1 was a 26-year-old man who had been admitted to our hospital for an elective minor operation. His chest radiology and chest computed tomography revealed a nodule in the left lung field. Peripheral blood eosinophil counts and serum IgE values were elevated. Radiological abnormality disappeared without treatment. Patient 2 was a 57-year-old man who had been admitted to our hospital because of a migratory nodule on chest radiography and eosinophilia in the peripheral blood. The diagnosis of visceral larva migrans caused by A. suum was made because the serum of both patients was positive for an antibody against A. suum. Patient 1 and patient 2 were accustomed to eating the raw flesh of wild boar and deer, and of chicken and turkey, respectively. Treatment with albentazole was effective in these patients.

Adult↗
PubMed2000

CD45 is required for CD40-induced inhibition of DNA synthesis and regulation of c-Jun NH2-terminal kinase and p38 in BAL-17 B cells.

Stimulation of B cell antigen receptor (BCR) may induce proliferation, differentiation, or apoptosis, depending upon the maturational stage of the cell and the presence or absence of signals transmitted via coreceptors. One such signal is delivered via CD40; for instance, ligation of CD40 rescues B cells from BCR-induced apoptosis. Here we show that, in contrast to WEHI-231 cells, CD40 ligation did not reverse BCR-induced growth inhibition in the BAL-17 mature B cell line and CD40 ligation itself inhibited proliferation. This inhibitory signaling was not observed in CD45-deficient cells. Further analyses demonstrate that transfection of dominant-negative form of SEK1 or treatment with SB203580 strongly reduced CD40-induced inhibition of BAL-17 proliferation, suggesting a requirement for c-Jun NH2-terminal kinase and p38 in CD40-induced inhibition of proliferation. Interestingly, CD40-initiated activation of c-Jun NH2-terminal kinase and p38 was enhanced and sustained in CD45-deficient cells, and these phenotypes were reversed by transfecting CD45 gene. However, CD40-mediated induction of cell surface molecules was not affected in CD45-deficient cells. Taken collectively, these results suggest that CD45 exerts a decisive effect on selective sets of CD40-mediated signaling pathways, dictating B cell fate.

Animals↗
PubMed2000

Src homology region 2 (SH2) domain-containing phosphatase-1 dephosphorylates B cell linker protein/SH2 domain leukocyte protein of 65 kDa and selectively regulates c-Jun NH2-terminal kinase activation in B cells.

Src homology region 2 (SH2) domain-containing phosphatase-1 (SHP-1) is a cytosolic protein tyrosine phosphatase containing two SH2 domains in its NH2 terminus. That immunological abnormalities of the motheaten and viable motheaten mice are caused by mutations in the gene encoding SHP-1 indicates that SHP-1 plays important roles in lymphocyte differentiation, proliferation, and activation. To elucidate molecular mechanisms by which SHP-1 regulates BCR-mediated signal transduction, we determined SHP-1 substrates in B cells using the substrate-trapping approach. When the phosphatase activity-deficient form of SHP-1, in which the catalytic center cysteine (C453) was replaced with serine (SHP-1-C/S), was introduced in WEHI-231 cells, tyrosine phosphorylation of a protein of about 70 kDa was strongly enhanced. Immunoprecipitation and Western blot analyses revealed that this protein is the B cell linker protein (BLNK), also named SH2 domain leukocyte protein of 65 kDa, and that upon tyrosine phosphorylation BLNK binds to SHP-1-C/S in vitro. In vitro kinase assays demonstrated that hyperphosphorylation of BLNK in SHP-1-C/S-expressing cells was not due to enhanced activity of Lyn or Syk. Furthermore, BCR-induced activation of c-Jun NH2-terminal kinase was shown to be significantly enhanced in SHP-1-C/S transfectants. Taken collectively, our results suggest that BLNK is a physiological substrate of SHP-1 in B cells and that SHP-1 selectively regulates c-Jun NH2-terminal kinase activation.

Adaptor Proteins, Signal Transducing↗
PubMed2000

Prevalence of Barrett's esophagus and expression of mucin antigens detected by a panel of monoclonal antibodies in Barrett's esophagus and esophageal adenocarcinoma in Japan.

Barrett's esophagus (BE) is an acquired disorder associated with a high incidence of adenocarcinoma of the lower esophagus. Moreover, it has been reported that short-segment BE may be associated with adenocarcinoma of the esophagogastric junction. The objective of this study was to define the prevalence of BE and the mucin profile in BE, including the short-segment type, and to compare the mucin profile in BE with the profiles of Barrett's adenocarcinoma and distal esophageal adenocarcinoma among Japanese. In total, 650 adult subjects underwent endoscopic examination for evaluation of BE. Although the prevalence of traditional (long segment) BE was 0.62%, the overall prevalence of BE including short-segment type was 15.7%. In Barrett's epithelium, the short-segment type predominantly had gastric type mucin, while the middle- and long-segment types possessed intestinal mucin, especially colonic type mucin (sulfo-Lewis(a)), with high frequency. In Barrett's epithelium with adenocarcinoma, all Barrett's epithelium adjacent to carcinomas showed a predominance of immunoreactivity to sulfo-Lewis(a). In Barrett's adenocarcinomas, colonic type mucin was detected in 100% by monoclonal antibody (MoAb) 91.9H. Small-intestinal mucin and gastric mucin were stained in 50% and 12.5% of the subjects, respectively. Colonic type mucin was also detected with high frequency (80%) in distal esophageal adenocarcinomas without Barrett's epithelium. These data suggest that the epitope, not of small-intestinal type or gastric type mucin, but of colonic type mucin (sulfo-Lewis(a)), may be associated with, at least in part, the malignant phenotype of BE.

Adenocarcinoma↗
PubMed2000

Microsatellite instability in patients with multiple primary cancers of the gastrointestinal tract.

BACKGROUND: Little is known about the genetic alterations in multiple primary cancers of the gastrointestinal tract. Microsatellite instability (MSI) is frequently observed in hereditary non-polyposis colorectal cancer (HNPCC), and multiple primary cancers is a feature of this syndrome. AIMS: To identify MSI incidence, target gene mutation, and mismatch repair (MMR) protein status in patients with multiple primary cancers of the gastrointestinal tract. SUBJECTS: Fifty seven cancers from 22 Japanese patients with multiple primary cancers of the stomach, duodenum, colon, and rectum. METHODS: MSI was examined at 5-7 microsatellite loci. Mutation analysis for TGFbetaRII, IGFIIR, and BAX was performed in cancers with MSI. MMR protein status was examined by immunohistochemical analysis using a monoclonal antibody against hMSH2 and hMLH1. RESULTS: MSI was observed in 16 of 22 patients (73%) and in 29 of 57 lesions (51%). High frequency MSI (MSI-H) was found often in patients with multiple cancers in the same organ (p = 0.042), especially in multiple gastric cancer patients (p = 0.038). In contrast, patients with multiple cancers in different organs had a tendency to show low frequency MSI (MSI-L) or microsatellite stable (MSS) phenotype. Both target gene mutation and decreased expression of MMR protein were found only in seven lesions of three patients with MSI at more than four microsatellite loci. CONCLUSIONS: These results suggest that genetic instability may play an important role in the development of multiple gastrointestinal cancers but there may be different genetic alterations between multiple gastrointestinal cancers of the same and different organs.

Aged↗
PubMed2000

[Valve replacement with cryopreserved allograft].

Allograft valves have several advantages such as 1) the absence of thromboembolic complications without anticoagulation, 2) superior durability to bioprosthetic valves, 3) good resistance to infection, 4) excellent hemodynamic performance especially in small sizes. Surgeons in western countries, therefore often use these valves and have reported good long-term results. In Japan, there have been only a small number of case reports on such valve replacement. We experienced five cases of valve replacement with cryopreserved allografts, four men and one woman. Four of them had formerly received AVR or Cabrol operation, and the prosthetic valve (graft) infection or aortitis syndrome was the main reason of reoperation. One 15 year-old woman suffering from congenital aortic stenosis underwent Ross operation with pulmonary allograft. Although one case with PVE received re-re-AVR 2 years and 4 months after the allograft replacement because of the recurrence of infection, the other four cases are in good condition long after the surgery. We hope that the use of allograft valves will become common in Japan.

Adolescent↗
PubMed2000

Epitope analysis of myeloperoxidase (MPO) specific anti-neutrophil cytoplasmic autoantibodies (ANCA) in MPO-ANCA-associated glomerulonephritis.

AIM AND METHODS: Epitope analysis of sera from 20 patients with myeloperoxidase anti-neutrophil cytoplasmic antibody- (MPO-ANCA) associated glomerulonephritis was examined by Western blotting using a panel set of recombinant deletion mutants of MPO. Sera from 19 patients reacted with recombinants of MPO heavy chain, whereas no serum reacted with the light chain regions. The high frequency sites were regions on the upstream of Met341 (Ha region), on the upstream of Met409 (Hb region) near the N-terminus of the MPO heavy chain and a region on the downstream of Gly598 (Hg region) near the C-terminus. The epitope recognition profiles were classified into 2 groups. Group A, which had 1 or 2 regions in Ha, Hb and Hg, and group B, which had all 3 regions. RESULTS: Incidence of alveolar hemorrhage (AH) and pulmonary fibrosis (PF) in group A was significantly higher than that in group B (AH: group A 9 of 13 (69.2%), group B 1 of 6 (16.7%) p < 0.05, PF: group A 10 of 13 (76.9%), group B 1 of 6 (16.7%) p < 0.05, AH and/or PH: group A 12 of 13 (92.3%) and group B 1 of 6 (16.7%) p < 0.01). Relapse rate for patients in the inactive stage in group A was significantly higher than that in group B (p < 0.05). T-cell reacted regions were Ha, Hb, Hg and the light chain of MPO recombinant fragments. Higher frequency of HLA typing with MHC class II DR9 was observed. CONCLUSION: These results indicate that MPO-ANCA recognizes the linear site of the heavy chain of the MPO molecule. The epitope recognition profiles are related to the clinical features, suggesting the pathogenesis of MPO-ANCA-associated glomerulonephritis.

Adult↗