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M Koike

Publications and source records attributed to M Koike.

At least 181 records · Page 10Linked to original sources
PubMed1997

[Extramedullary plasmacytoma with multiple metastasis following a maxillary plasmacytoma].

A 67-year old man noticed swelling of left maxillary in October 1992. Surgical biopsy of the left maxillary tumor revealed the plasmacytoma at the department of oral surgery. The Tumor disappeared after radiation therapy. He was admitted with dizziness and tarry stool in June 1994. We found left cervical and abdominal paraaortic lymph node swellings by the computer tomography. He died inspite of chemotherapy in December. Autopsy showed that plasma cells diffusely and nodularly invased in all alimentary tract with multiple ulcerations. Invasion was also observed in the liver, lungs, thyroid, heart, kidneys, and adrenals. The plasma cells in the liver showed IgG kappa type by tissue immunostain. Diffuse invasion of extramedullary plasmacytoma is very rare in alimentary tract and many other organs. This case may be value to delineate the nature of this disease.

Aged↗
PubMed1997

Microsatellite instability and loss of heterozygosity in gastric lymphoma.

To evaluate the significance of microsatellite instability (MI) and loss of heterozygosity (LOH) in the development of gastric lymphoma, we examined 33 tissue-samples of 20 primary gastric B-cell lymphomas (6 low-grade lymphomas of mucosa-associated lymphoid tissue [MALT; 10 samples] and 14 diffuse large B-cell lymphomas [23 samples]). MI and LOH were evaluated at 13 microsatellite loci. In MALT lymphoma, four of six cases showed MI at one to two microsatellite loci (average 1.0 per case, 0.8 per sample), whereas in diffuse B-cell lymphoma, all samples showed MI at one to five microsatellite loci (average 2.4 per case, 2.7 per sample) (p < 0.05 and p = 0.0001). MI at the c-myc gene locus was most frequent in both types of gastric lymphomas (3 of 6 and 11 of 14 cases, respectively). Regional heterogeneity of the MI pattern was observed in two of four cases of MALT lymphoma and in four of five cases of diffuse B-cell lymphoma. On the other hand, LOH was observed only in one MALT lymphoma and in three diffuse B-cell lymphomas. Genetic instability may be an important mechanism for the development and progression of gastric lymphoma. Frequent MI at the c-myc locus might reflect an activated state and the importance of this gene in mucosal lymphocytes of chronic gastritis.

Adult↗
PubMed1996

DMSO induces apoptosis in SV40-transformed human keratinocytes, but not in normal keratinocytes.

We found that dimethyl-sulfoxide (DMSO) at concentrations of 2.5% induced apoptosis in SV40-immortalized human keratinocytes, while normal keratinocytes were arrested at the boundary of G1/S phase under the same conditions. DMSO-induced apoptosis in SV-40 immortalized keratinocytes was not associated with change in phosphorylated state of the retinoblastoma susceptibility gene. When SV40-immortalized cells were treated with 2.5% DMSO, dissociation of the complex was observed by immunoblotting of SV40 T antigen from immunoprecipitated p53 protein fraction.

Antigens, Viral, Tumor↗
PubMed1996

Chromosomal localization of the mouse and rat DNA double-strand break repair genes Ku p70 and Ku p80/XRCC5 and their mRNA expression in various mouse tissues.

The Ku p70 and Ku p80/XRCC5 genes are involved in DNA double-strand break repair and V(D)J recombination, and their gene products are the components of the DNA-dependent protein kinase. We have determined the chromosomal locations of the mouse Ku p70 and Ku p80/XRCC5 genes by both in situ hybridization and molecular linkage analysis: the Ku p70 gene was localized to mouse chromosome 15 and rat chromosome 7, and the Ku p80/XRCC5 gene was localized to mouse chromosome 1 and rat chromosome 9. Both genes were mapped to a region of conserved linkage homology among three species, i.e., the mouse, rat, and human. Molecular linkage analysis using interspecific backcross mice revealed that the murine Ku p70 locus was localized 0.7 cM terminal to D15Mit1 and that the murine Ku p80/XRCC5 locus was 0.7 cM proximal to D1Mit46. To determine the size and tissue transcription specificity of the mouse Ku p70 and Ku p80/XRCC5 mRNA, Northern blot analysis was carried out with six mouse tissues. Each tissue expressed one species of the Ku p70 gene transcript with 2.4 kb and one species of the Ku p80/XRCC5 gene transcript with 2.6 kb. In the latter case, however, the brain showed two sizes of transcript, 2.6 and 2.9 kb.

Animals↗
PubMed1996

Voltage-dependent blockage of Ca(2+)-permeable AMPA receptors by joro spider toxin in cultured rat hippocampal neurones.

1. The effect of synthetic joro spider toxin (JSTX-3) on alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor channels in cultured rat hippocampal neurones was investigated using the whole-cell patch-clamp technique. 2. A population of cultured neurones had AMPA receptors with strong inward rectification and substantial Ca2+ permeability (type II neurones), whereas most neurones (type I neurones) had slight outward rectification and little Ca2+ permeability. JSTX-3 selectively suppressed the inwardly rectifying and Ca(2+)-permeable AMPA receptors expressed in type II neurones without affecting AMPA receptors in type I neurones. 3. The effect of JSTX-3 on the Ca(2+)-permeable AMPA receptors was use and voltage dependent. In the steady state, current responses induced by ionophoretic applications of kainate (a non-desensitizing agonist of AMPA receptors) were suppressed by the toxin in a dose-dependent manner at negative potentials (IC50 = 56 nM at -60 mV). 4. At the standard membrane potential (-60 mV), recovery from the blockage by JSTX-3 was very slow. Even after washout for more than 7 min, the recovery was only partial. However, the blockage was completely removed immediately after application of a +60 mV voltage pulse for 5 s in conjunction with a single ionophoretic application of kainate.

Animals↗
PubMed1996

Acceleration of proliferative activity of esophageal squamous cell carcinoma with invasion beyond the mucosa: immunohistochemical analysis of Ki-67 and p53 antigen in relation to histopathologic findings.

BACKGROUND: The authors observed patients with superficial esophageal squamous cell carcinoma (s-ESC). Those with cancer invasion beyond the muscularis mucosae (SM-carcinoma) had an extremely poor prognosis, compared with those with intramucosal carcinoma (M-carcinoma). Therefore, we surveyed cell proliferative activities in relation to pathologic findings of the s-ESC. METHODS: p53 protein expression and Ki-67 labeling index (LI) were surveyed with detailed pathologic examinations of 75 s-ESC lesions from 70 patients who underwent esophagectomy. The results were compared by statistical analysis using the chi-square test and unpaired Student's t-test. RESULTS: p53 protein expression was observed in 57.3% of the patients with s-ESC. The frequency and intensity of its accumulation correlated with the depth of cancer invasion and was markedly elevated in invasion beyond the muscularis mucosae. The LI of Ki-67 positive nuclei was also increased with cancer invasion. The values in the intraepithelial carcinoma and in carcinoma with invasion to the muscularis mucosae were 48.5 +/- 13.7% [mean +/- standard deviation (SD)] and 66.6 +/- 12.9%, respectively, and the difference is significant, P < 0.01. In the SM-carcinomas, the LIs of Ki-67, with or without lymph node metastasis, were 73.5 +/- 10.0% and 64.4 +/- 11.3%, respectively, and the former was higher than the latter with a significant difference, P < 0.05. CONCLUSIONS: Cancer cell proliferative activities were markedly accelerated in s-ESC cases with cancer invasion beyond the muscularis mucosae and lymph nodal involvement, which was associated with a poorer prognosis of the SM-carcinoma compared with the M-carcinoma, and must be one of the important indices to decide the indication of local resection for s-ESC.

Aged↗
PubMed1996

Frequent loss of heterozygosity in region of the KIP1 locus in non-small cell lung cancer: evidence for a new tumor suppressor gene on the short arm of chromosome 12.

To refine the chromosomal localization of a putative tumor suppressor gene, we analyzed the loss of heterozygosity (LOH) of chromosome 12 in 36 primary non-small cell lung cancer (NSCLC) samples with matched normal DNA using 22 highly informative polymorphic markers. Twelve cases showed LOH at one or more loci on chromosome 12. LOH of chromosome arm 12p was more frequent in large cell carcinoma than squamous cell carcinoma, indicating molecular genetic heterozygosity within the major NSCLC subtypes. We identified the smallest commonly deleted region on chromosome 12p13. This region is flanked by D12S269 and D12S308, including the KIP1 gene. Mutational analysis of KIP1 using PCR-single strand conformation polymorphism and Southern Blot analysis showed no homozygous deletions, rearrangements, or point mutations, suggesting that the altered gene in this region is not the KIP1 gene. These data suggest that a new tumor suppressor gene which is involved in tumorigenesis of NSCLC is in the region of KIP1.

Carcinoma, Non-Small-Cell Lung↗
PubMed1996

Significance of spontaneous apoptosis during colorectal tumorigenesis.

To determine if apoptosis is involved in colorectal tumorigenesis and its progression, colorectal adenomas (n = 63), carcinomas (n = 49), and normal mucosa were investigated by using in situ end-labeling (TUNEL) method. The expression of Ki-67 was also analyzed immunohistochemically. TUNEL labeling index (TLI) and Ki-67 labeling index (KLI) were determined. TLI/KLI was significantly higher in the adenomas of small size and/or of low and middle grade atypia than those of large size and/or of high grade atypia. No difference was observed in the indices between adenomas and carcinomas and among the cancer groups classified on the basis of their clinicopathological features. The results indicate that the reduction of susceptibility to apoptosis plays an important role in the early stage of the adenoma-carcinoma sequence. Apoptosis can explain the enormous cell loss thought to exist in normal colorectal mucosa and in the tumor growth process.

Adenoma↗
PubMed1996

Apoptosis of T cells in multicentric Castleman's disease.

Profound immunodeficiency in multicentric Castleman's disease has already been elucidated. In the present study, we investigated CD45RO and Fas antigen expression and apoptosis by T cells in three patients with this disease. T cell expression of CD45RO and Fas antigen was increased in two of the three patients, indicating in vivo lymphocyte activation. Apoptosis of T cells from the two patients with increased CD45RO and Fas antigen expression occurred after overnight culture in the presence of pokeweed mitogen. Occurrence of apoptosis was indicated by DNA laddering and nuclear chromatin condensation. Peripheral blood mononuclear cells from the two MCD patients revealed spontaneous apoptosis following 3 days of culture by quantitative assay using flow cytometry. These findings show that T cells are activated in some patients with multicentric Castleman's disease and suggest that this activation may promote apoptosis.

Apoptosis↗
PubMed1996

Fibrillary inclusions in neoplastic and fetal acinar cells of the pancreas.

We report a case of pancreatic acinar cell carcinoma which contained a large number of pleomorphic inclusions with fibrillary internal structures and mature zymogen granules. To clarify the significance of fibrillary inclusions in the differentiation of acinar cells of the pancreas, we further investigated fetal pancreases (gestational weeks 16, 17, 19, 20 and 28). We found two types of inclusions: type A, corresponding to fibrillary inclusion of neoplastic acinar cells, was observed only in a 19-week fetus; type B showed a homogeneous density similar to that of zymogen granules. Type B was observed in all the fetuses after the 17th gestational week. Although the type A inclusion might be generated through a different mechanism than the type B inclusion, the appearance of a large number of fibrillary inclusions in neoplastic acinar cells may represent a transient form of zymogen granule.

Carcinoma, Acinar Cell↗
PubMed1996

Effects of immunoglobulin and gamma-interferon on the production of tumour necrosis factor-alpha and interleukin-1 beta by peripheral blood monocytes in the acute phase of Kawasaki disease.

In order to study the in vitro effects of intact immunoglobulin (Ig) and gamma-interferon (INF-gamma) in patients with Kawasaki disease, the production of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) was measured in peripheral blood monocytes (PBM) both before and after intravenous immunoglobulin (IVIG) therapy. Spontaneous production of TNF-alpha and IL-1 beta both before and after IVIG therapy was significantly higher than in healthy controls. Intact Ig enhanced in vitro the production of TNF-alpha and IL-1 beta both before and after IVIG therapy approximately 3-4 times as compared to the spontaneous production. INF-gamma did not affect the production of the two cytokines. Ig enhanced IL-1 beta mRNA expression in PBM of KD by 3-8 times more than that of spontaneous production.

Acute Disease↗
PubMed1996

Role of endogenous hypergastrinemia in regenerating endocrine pancreas after partial pancreatectomy.

We studied the possible role of endogenous gastrin in the regenerating pancreas. Male Wistar rats underwent sham operation or 90% partial pancreatectomy (Px). Lansoprazole (30 mg/kg body wt), a proton pump inhibitor (PPI), was given p.o. for 3 weeks after surgery. Plasma glucose levels were higher in Px rats than in shams. Lansoprazole lowered plasma glucose levels in the Px rats. In addition, integrated insulin secretion during an oral glucose tolerance test (2 g/kg body wt) was significantly (p < 0.01) higher in lansoprazole-treated Px rats than in control Px rats, while lansoprazole did not affect insulin secretion in shams. Fasting serum gastrin levels were higher (p < 0.01) in lansoprazole-treated animals than in controls both in sham rats and in Px rats. Furthermore, lansoprazole increased the pancreas weight per body weight and elevated the insulin content of the pancreas in Px rats. These results suggest that endogenous hypergastrinemia has a trophic effect on endocrine pancreas during regenerating processes and that administration of PPI may be clinically beneficial to the remnant pancreas after pancreatectomy if the whole stomach is preserved.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1996

Cyclophosphamide-induced apoptosis induces phocomelia in the mouse.

Phocomelia (absence of upper fore and/or hind limbs) was induced in mouse fetuses using cyclophosphamide. On day 11 of gestation, pregnant mice were injected intraperitoneally with 10 ml/kg of saline containing cyclophosphamide (CP) at a dosage of 20 mg/kg body weight. On day 18, the fetuses were removed by Caesarean section from dams given CP on day 11 and were examined for external anomalies. Of 22 fetuses from CP-treated dams, 13 were dead or absorbed, but the surviving 9 fetuses were found to have phocomelia with various other external anomalies. In order to examine the direct cytotoxic effect of CP on fetal limb buds, fetuses were removed at 8, 16, 24, and 48 h after CP administration on day 11, revealing the presence of frequent pyknotic nuclei and apoptotic bodies in hematoxylin and eosin (H & E) preparations. Cell-nuclei and apoptotic bodies were frequently observed by nick end-labeling in limb buds. Transmission electron microscopy demonstrated the typical changes of apoptosis. DNA extracted from the fetal limb buds submitted to CP was analysed by agarose gel electrophoresis, showing the ladder pattern characteristic of internucleosomal cleavage. These findings suggest that cyclophosphamide causes apoptosis in mouse fetal limb buds and that this process induces the external anomalies of phocomelia.

Animals↗
PubMed1996

Interleukin-6 receptor expression in the peripheral B cells of patients with multicentric Castleman's disease.

Interleukin-6 (IL-6) is an important regulator of terminal B-cell differentiation. Inappropriate oversynthesis of IL-6 may play primary role in the pathogenesis of multicentric Castleman's disease (MCD). We investigated the expression of the IL-6 receptor (IL-6R) in peripheral B cells from three patients with MCD, as well as the responsiveness of these cells to IL-6. Flow-cytometric analysis showed that IL-6R was significantly expressed on the peripheral B cells of two of three patients. The B cells expressing IL-6R spontaneously produced increased levels of immunoglobulin G (IgG). IL-6R-expressing B cells from one patient showed hyper-responsiveness to IL-6.

Antibody Formation↗
PubMed1996

Natural killer (NK) lymphocytosis induced by Epstein-Barr virus (EBV) reactivation in monoclonal gammopathy of undetermined significance (MGUS).

We investigated the relationship between NK lymphocytosis and EBV infection in MGUS. We found that two out of 10 patients showed an increase of NK cells compared with normal controls In addition, these two patients had far higher levels of CD5LOW+ NK cells (activated NK cells) than controls. EBV DNA was detected by polymerase chain reaction in peripheral blood mononuclear cells from the two patients, although the other eight patients with MGUS and all 20 normal controls had no detectable EBV DNA. Furthermore, EBV DNA was detected in sorted CD5LOW+ NK cells. These results suggest that reactivation of EBV might be related to the increase of NK cells, particularly CD5LOW+ NK cells in some patients with MGUS.

Adult↗
PubMed1996

Heat shock-enhanced T cell apoptosis with heat shock protein 70 on T cell surface in multicentric Castleman's disease.

We report here that T cells from patients with multicentric Castleman's disease (MCD) are sensitive to hyperthermia. T cells from two of three patients with MCD revealed DNA ladder formation and chromatin condensation following heat shock (30 min at 41.5 degrees C). Peripheral blood mononuclear cells (PBMC) from the same MCD patients exhibited high levels of spontaneous apoptosis after 72 h in culture and elevated apoptosis after heat shock, as evaluated by a quantitative flow cytometric assay. Heat shock protein 70 (hsp70) was detected on the cell surface of T cells in all three patients after heat shock. Furthermore, hsp70 was detected on T cells in the two MCD patients with apoptosis even in the absence of heat shock. T cells from normal samples did not show either heat-shock-induced expression of cell-surface hsp70 or apoptosis. Thus, heat shock treatment augmented hsp70 expression on the cell surface of T cells and enhanced apoptosis. Our studies suggest that hyperthermia may influence the clinical course of MCD.

Antigens, Surface↗