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M Kuriyama

Publications and source records attributed to M Kuriyama.

At least 19 recordsLinked to original sources
PubMed2002

Eradication of Helicobacter pylori infection induces an increase in body mass index.

BACKGROUND: The relationship between H. pylori infection and body mass indices is controversial. AIM: To investigate the relationship between H. pylori infection and body indices, and to examine the effect of H. pylori eradication therapy on body indices. METHODS: Nine-hundred and thirty-two employees of an industrial corporation were examined for H. pylori infection and body mass indices. Three hundred and two H. pylori-positive cases diagnosed with chronic gastritis by upper gastrointestinal endoscopy or radiography underwent eradication therapy. Body mass indices, serum total cholesterol levels and symptom scores were obtained before and at 12 months after eradication therapy. RESULTS: There was no significant difference in body weight, body mass index (BMI) or serum total cholesterol level between the H. pylori-positive and H. pylori-negative groups. However, body weight and BMI increased significantly 12 months after eradication of H. pylori infection. In contrast, there was no significant difference in body weight and BMI 12 months after eradication therapy in the non-eradication group. Serum total cholesterol levels did not change after eradication therapy in either the eradication or non-eradication groups. CONCLUSION: Eradication of H. pylori infection induced an increase in BMI in industrial workers with chronic gastritis in Japan.

Adult↗
PubMed2001

Diacylglycerol kinase gamma is one of the specific receptors of tumor-promoting phorbol esters.

Diacylglycerol kinase (DGK) and protein kinase C (PKC) are two different enzyme families that interact with diacylglycerol. Both enzymes contain cysteine-rich C1 domains with a zinc finger-like structure. Most of the C1 domains of PKCs show strong phorbol-12,13-dibutyrate (PDBu) binding with nanomolar dissociation constants (K(d)'s). However, there has been no experimental evidence that phorbol esters bind to the C1 domains of DGKs. We focused on DGK gamma because its C1A domain has a high degree of sequence homology to those of PKCs, and because DGK gamma translocates from the cytoplasm to the plasma membrane following 12-O-tetradecanoylphorbol-13-acetate treatment similar to PKCs. Two C1 domains of DGK gamma (DGK gamma-C1A and DGK gamma-C1B) were synthesized and tested for their PDBu binding along with whole DGK gamma (Flag-DGK gamma) expressed in COS-7 cells. DGK gamma-C1A and Flag-DGK gamma showed strong PDBu binding affinity, while DGK gamma-C1B was completely inactive. Scatchard analysis of DGK gamma-C1A and Flag-DGK gamma gave K(d)'s of 3.1 and 4.4 nM, respectively, indicating that the major PDBu binding site of DGK gamma is C1A. This is the first evidence that DGK gamma is a specific receptor of tumor-promoting phorbol esters.

Amino Acid Sequence↗
PubMed2001

Tyrosine phosphorylation of the catalytic subunit p110 of phosphatidylinositol-3 kinase induced by HMG-CoA reductase inhibitor inhibits its kinase activity in L6 myoblasts.

Previous studies from this laboratory have shown that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (HCRI) causes apoptotic cell death of a muscle cell-derived cell line, L6 myoblasts, by involving the phosphatidylinositol-3 (PI-3) kinase pathway and tyrosine phosphorylation of several cellular proteins, although the relationship between PI-3 kinase pathway and tyrosine phosphorylation responses remained to be elucidated. Here, we show that HCRI induces tyrosine phosphorylation of catalytic subunit p110 of PI-3 kinase as early as 5 min after addition of HCRI into culture medium. We could not detect the tyrosine phosphorylation of the regulatory subunit p85 of PI-3 kinase under the present experimental conditions. Concomitantly, the kinase activity toward PI in p110 immunoprecipitates was decreased with a similar time course. Furthermore, both herbimycin A and genistein, potent inhibitors of tyrosine kinase activity, inhibited HCRI-induced inhibition of PI-3 kinase activity as well as HCRI-induced apoptotic cell death. Once the catalytic subunit p110 becomes tyrosine-phosphorylated, the regulatory subunit p85 appears to be dissociated from the catalytic subunit, because we observed a decreasing amount of p85 regulatory subunits in p110 immunoprecipitates in response to HCRI treatment. These results strongly suggest the novel function of tyrosine phosphorylation of catalytic subunit p110 of PI-3 kinase in the regulation of its kinase activity. The tyrosine phosphorylation of these catalytic subunits may play an important role in the intracellular signal transduction of apoptotic cell death. To our knowledge, this is the first report that tyrosine phosphorylation of p110 catalytic subunit acts as a negative regulator of its kinase activity.

Animals↗
PubMed2001

MK-801 is cytotoxic to microglia in vitro and its cytotoxicity is attenuated by glutamate, other excitotoxic agents and atropine. Possible presence of glutamate receptor and muscarinic receptor on microglia.

We examined the cytotoxicity of MK-801 on cultured microglia and demonstrated its cytotoxicity. Cytotoxicity of MK-801 was reduced by the addition of L-glutamate, kainate and NMDA. The action of MK-801 was due to the direct action of microglia. It suggested the existence of glutamate receptor in microglia. Cytotoxicity of MK-801 was reduced by the addition of atropine sulfate which suggested the presence of muscarinic receptor in microglia.

Animals↗
PubMed2001

Effects of CYP2C19 gene polymorphism on cure rates for Helicobacter pylori infection by triple therapy with proton pump inhibitor (omeprazole or rabeprazole), amoxycillin and clarithromycin in Japan.

BACKGROUND: Omeprazole is mainly metabolized by cytochrome P450 2C19 (CYP2C19) in the liver. Rabeprazole, on the other hand, is mainly metabolized to thioether-rabeprazole via a non-enzymatic pathway and partially metabolized to demethylated-rabeprazole by CYP2C19 in liver CYP2C19 status may affect cure rate for Helicobacter pylori infection with proton pump inhibitor triple therapy. AIM: To investigate whether genetic polymorphism of CYP2C19 and selected proton pump inhibitors (omeprazole or rabeprazole) were associated with cure rate for Helicobacter pylori infection using triple therapy with omeprazole or rabeprazole, amoxicillin, and clarithromycin. METHODS: A total of 170 Helicobacter pylori-positive patients with chronic gastritis were randomized to receive one of the following Helicobacter pylori eradication regimens; OAC (omeprazole 20 mg bd, amoxycillin 750 mg bd and clarithromycin 400 mg bd for 1 week) and RAC (rabeprazole 20 mg bd, amoxycillin 750 mg bd and clarithromycin 400 mg bd for 1 week). The CYP2C19 genotype; wild-type or two mutant genes (ml in exon 5 and m2 in exon 4), or both, were identified by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: In DAC regimen, cure rate (per protocol analysis) was 73.3% in homozygous extensive metabolizers, 86.1% in heterozygous extensive metabolizers, and 85.0% in poor metabolizers. In RAC regimen, the cure rate was 81.0% in homozygous extensive metabolizers, 82.9% in heterozygous extensive metabolizers, and 87.5% in poor metabolizers. Cure rate was not significantly different between the CYP2C19 genotypes in both regimens. CONCLUSION: Triple therapy with proton pump inhibitor (omeprazole or rabeprazole), amoxycillin, and clarithromycin is sufficiently effective in cure of Helicobacter pylori infection regardless of CYP2C19 status.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

The effect of Helicobacter pylori eradication therapy on dyspepsia symptoms in industrial workers in Japan.

BACKGROUND: The relationship between Helicobacter pylori infection and non-ulcer dyspepsia is still controversial. The potential benefits and risks of the treatment could depend on local conditions, such as the prevalence of the infection and the local rates of gastric cancer. AIM: To evaluate the effects of H. pylori eradication therapy on non-ulcer dyspepsia symptoms in industrial workers in Japan. METHODS: A total of 615 employees of an industrial corporation were examined for H. pylori infection and symptom scores; 215 H. pylori-positive non-ulcer dyspepsia cases underwent eradication therapy. Symptom scores were also analysed 12 months after the eradication therapy. Serum pepsinogen A and pepsinogen C levels were analysed and chronic atrophic gastritis was serologically diagnosed on the basis of the criteria of a pepsinogen A < 70 ng/mL and pepsinogen A : pepsinogen C ratio < 3.0. RESULTS: The symptom score improved significantly in the cured cases, but not in the non-cured cases. The effect of the cure of H. pylori infection on symptoms was analysed according to the serological diagnosis of chronic atrophic gastritis. In both groups, cases with atrophic gastritis and cases with chronic gastritis only, the cure of infection was effective in improving symptoms. CONCLUSION: The cure of H. pylori infection was effective in reducing non-ulcer dyspepsia symptoms in industrial workers in Japan.

Adult↗
PubMed2001

Determination of serum prostate-specific antigen-alpha1-antichymotrypsin complex for diagnosis of prostate cancer in Japanese cases.

OBJECTIVE: The clinical utility of the determination of serum prostate-specific antigen-alpha1-antichymotrypsin complex (PSA-ACT) for the diagnosis of prostate cancer, especially in cases in the diagnostic gray zone, is still unclear. MATERIAL AND METHODS: With the use of a newly approved enzyme immunoassay for the detection of PSA-ACT, 907 sera, including those from non-urological benign and malignant diseases, were analysed. RESULTS: Serum values of PSA-ACT in non-prostate cancer males increased according to age from the 40s to 70s. The serum values were high only in the patients with prostatic diseases and, in prostate cancer patients, the values became high as the clinical stage progressed. By receiver-operating characteristic analysis significantly better results in PSA-ACT than total PSA were observed. In the group with a total PSA of 2-20 ng/ml, the detection of PSA-ACT showed better results, although not significantly so, than the free-to-total PSA ratio. CONCLUSIONS: The detection of PSA-ACT showed a high clinical utility in the diagnosis of prostate cancer. Therefore, it may replace total PSA determination.

Adult↗
PubMed2001

Prospective and randomized comparison of combined androgen blockade versus combination with oral UFT as an initial treatment for prostate cancer.

OBJECTIVE: This prospective and randomized clinical study was initiated to compare the efficacy and safety of combined androgen blockade with combination with UFT in patients with untreated prostate cancer. METHODS: A total of 142 patients were entered in this study between April 1990 and December 1992. All patients received bilateral orchiectomy and 200 mg/day of diethylstilbestrol diphosphate. Of these patients, 70 patients were administered an additional 400 mg/day of UFT after randomization. Either treatment was continued for at least 1 year or until objective progression occurred if the initial response was equal to or better than no change. The endpoints of this study were progression-free survival, cancer-specific survival and change of QOL scores. RESULTS: A total of 136 patients were evaluable and 131 patients (96.3%) could be followed up with a median follow-up period of 1469 days. Both groups showed similar initial treatment response at 12 weeks, adverse effect and change of quality of life score during the first year after initiation of the treatment. There was a significantly longer progression-free survival and better but not significant cancer-specific survival in the endocrine chemotherapy group. The patients with earlier stage and initial serum prostate-specific antigen values <40 ng/ml showed a good indication for this endocrine chemotherapy. CONCLUSION: This endocrine chemotherapy was confirmed to be tolerable and significantly effective in the delay of disease progression, which leads to longer survival in patients with prostate cancer.

Aged↗
PubMed2001

Helicobacter pylori infection induces hyperammonaemia in Mongolian gerbils with liver cirrhosis.

BACKGROUND AND AIMS: We previously reported the effect of Helicobacter pylori eradication on hyperammonaemia in patients with liver cirrhosis. However, the role of H pylori as a cause of hyperammonaemia is controversial. We developed an animal model with liver cirrhosis and investigated the effect of H pylori infection on hyperammonaemia. MATERIALS AND METHODS: Five week old male Mongolian gerbils were inoculated orally with broth culture of H pylori. Forty eight gerbils were divided into four groups. Gerbils not inoculated with H pylori were fed a commercial rodent diet (group A) or a choline deficient diet (group C). Gerbils inoculated with H pylori were fed the commercial rodent diet (group B) or the choline deficient diet (group D). Blood ammonia levels of the femoral vein and portal vein were measured 30 weeks later. RESULTS: All gerbils fed the choline deficient diet developed liver cirrhosis with fatty metamorphosis. The survival rate of group D was significantly lower than that of the other groups. Systemic and portal blood ammonia levels in group D were significantly higher than those in the other groups. CONCLUSIONS: H pylori infection induces hyperammonaemia in gerbils with liver cirrhosis.

Animals↗
PubMed2001

Gastric leptin and Helicobacter pylori infection.

BACKGROUND: Leptin regulates feeding behaviour and therefore may be a mediator of anorexia associated with acute and chronic inflammation. Recently, leptin mRNA and leptin protein were found in the gastric epithelium. AIM: The aim of the present study was to examine the effect of Helicobacter pylori infection on gastric leptin expression to investigate the pathophysiological role of gastric leptin. METHODS: Surgically resected human stomach tissues were subjected to immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) to check for the presence of leptin in the human gastric epithelium. A total of 201 H pylori positive patients with chronic gastritis underwent eradication therapy for H pylori and were examined for the effect of infection cure in terms of body mass index (BMI) and serum leptin levels. Biopsy specimens from the gastric fundic mucosa were obtained from 40 of the 201 patients before and three months after eradication therapy. These samples were subjected to quantitative RT-PCR to examine the effect of eradication therapy on leptin expression in the gastric fundic mucosa. RESULTS: Leptin immunoreactive cells were detected in the lower half of the gastric fundic glands and a leptin PCR product was also found in the gastric fundic mucosa. H pylori infection significantly increased gastric leptin expression. In addition, cure of H pylori infection significantly reduced gastric leptin expression, with a concomitant increase in BMI. In contrast, serum leptin levels did not change significantly after cure of H pylori infection. CONCLUSION: Leptin is present in the human gastric mucosa. Gastric leptin may play a role in weight gain after eradication of H pylori infection. Gastric leptin may have a local rather than systemic action.

Adult↗
PubMed2001

Spontaneous echo contrast in descending aorta correlates with low blood-flow velocity in carotid arteries and hemostatic abnormalities.

Spontaneous echo contrast in the descending aorta (DA-SEC) was examined as a possible risk factor for cerebral thromboembolism. In 19 patients (10 males, 9 females) in the chronic stage of cerebral infarction, abnormal findings by transesophageal echocardiography, flow dynamics of the common carotid artery (CCA), and hemostatic factors including blood coagulation and fibrinolysis were investigated. In nine patients, DA-SEC was detected, and SEC in left atrium (LA-SEC) was detected in nine patients. The DA-SEC positive group showed decreased blood-flow velocity (BFV) in bilateral CCA, high levels of thrombin-antithrombin III complex (TAT) and prothrombin fragment 1.2 (F1+2), a decrease in platelet count and a slight increase in D-dimer, which means an activated state of thrombin generation and resulting fibrinolysis, compared to the DA-SEC negative group. On the other hand, the LA-SEC positive group showed normal BFV in CCA and only a slight increase in D-dimer. We conclude that the condition producing DA-SEC is a stronger risk factor for cerebral infarction than that producing LA-SEC.

Aged↗
PubMed2001

[Isolated cerebral and myocardial perfusion during aortic arch repair in neonates].

OBJECTIVES: To prevent possible neurologic injury after hypothermic circulatory arrest, aortic arch obstruction with cardiac defects is repaired in one stage using isolated cerebral and myocardial perfusion (ICMP). This study investigated serum S-100 protein(S-100) levels in neonates undergoing ICMP. METHODS: Between February 2000 and January 2001, 19 neonate patients underwent repair of critical congenital heart defects. Seven of these patients with aortic coarctation(n = 3) or interrupted aortic arch (n = 4) with ventricular septal defect(ICMP group) underwent primary total repair. An arterial cannula was inserted either into the ascending aorta or into a polytetrafluoroethylene graft which was anastomosed to the innominate artery. During arch repair, a cross-clamp was placed between the innominate and left carotid arteries, and an end-to-end arch anastomosis was performed with cerebral perfusion and heart beating. During ICMP the flow was reduced to maintain a radial artery pressure of 30-45 mmHg. The remaining 12 patients underwent complete transposition of great arteries(n = 9) or total anomalous pulmonary venous connection(n = 3) using a cardiopulmonary bypass(CPB) with flow of 150-180 ml/kg/min(control group). Sequential blood samples for S-100 determinations were taken after induction of anesthesia, 30 min after aortic declamping(post-ACC), 30 min after CPB, and 24 hr after CPB. RESULTS: There were no early and late deaths. Neurologic symptoms were not observed in any patients. Mean ICMP time in ICMP group was 17 +/- 4 min. In all patients, S-100 showed the highest value post-ACC and then declined with time. There were no differences in S-100 between the groups at any other time point. CONCLUSIONS: Selective cerebral perfusion through the innominate artery may be able to maintain brain circulation.

Aorta, Thoracic↗
PubMed2001

Soluble CD154 in rheumatoid arthritis: elevated plasma levels in cases with vasculitis.

OBJECTIVE: To determine the levels of soluble CD154 (sCD154) in the plasma of patients with rheumatoid arthritis (RA) and rheumatoid vasculitis (RV). and to examine the relationship between the levels of sCD154 in plasma and the clinical variables. METHODS: Levels of sCD154 were quantified in 39 plasma samples from patients with RA, including 9 patients who were also diagnosed with RV, and compared with those of 20 healthy subjects. An ELISA was established and specificity of the ELISA was tested by control ELISA using isotype-matched IgG and preabsorption assay. The titers of IgM and IgG rheumatoid factor (IgM-RF, IgG-RF) for each patient were determined simultaneously, and values of other laboratory variables were also determined. RESULTS: Levels of sCD 154 in plasma were higher in patients with RA than in the healthy subjects (p < 0.02). Compared with RA patients without vasculitis, patients with RV had significantly higher levels of sCD154 in their plasma (p < 0.001). Control ELISA and absorption assay of sCD154 indicated that our ELISA system was capable of measuring plasma sCD154 in RA patients. Levels of sCD154 in RA plasma correlated significantly with both IgM-RF and IgG-RF titers (r = 0.64 and 0.61, respectively, both p < 0.001). The levels of sCD154 decreased after commencement of treatment for vasculitis in cases with RV. CONCLUSION: We identified the presence of sCD154 in RA plasma, with especially high levels in cases with vasculitis. Correlation between sCD154 and RF titers indicates the CD154-CD40 pathway is likely related to pathogenic RF production.

Adult↗
PubMed2000

Improvement of apraxia of eyelid opening by wearing goggles.

Apraxia of eyelid opening (ALO) is a non-paralytic motor abnormality characterised by difficulty in initiating the act of eyelid opening without blepharospasm. We found that wearing goggles improved the difficulty of opening eyes in two patients with ALO with parkinsonism. Wearing goggles is a simple method for improving daily life in patients with ALO.

Aged↗
PubMed2000

Subtype-specific translocation of diacylglycerol kinase alpha and gamma and its correlation with protein kinase C.

We examined the translocation of diacylglycerol kinase (DGK) alpha and gamma fused with green fluorescent protein in living Chinese hamster ovary K1 cells (CHO-K1) and investigated temporal and spatial correlations between DGK and protein kinase C (PKC) when both kinases are overexpressed. DGKalpha and gamma were present throughout the cytoplasm of CHO-K1 cells. Tetradecanoylphorbol 13-acetate (TPA) induced irreversible translocation of DGKgamma, but not DGKalpha, from the cytoplasm to the plasma membrane. The (TPA)-induced translocation of DGKgamma was inhibited by the mutation of C1A but not C1B domain of DGKgamma and was not inhibited by staurosporine. Arachidonic acid induced reversible translocation of DGKgamma from the cytoplasm to the plasma membrane, whereas DGKalpha showed irreversible translocation to the plasma membrane and the Golgi network. Purinergic stimulation induced reversible translocation of both DGKgamma and alpha to the plasma membrane. The timing of the ATP-induced translocation of DGKgamma roughly coincided with that of PKCgamma re-translocation from the membrane to the cytoplasm. Furthermore, re-translocation of PKCgamma was obviously hastened by co-expression with DGKgamma and was blocked by an inhibitor of DGK (R59022). These results indicate that DGK shows subtype-specific translocation depending on extracellular signals and suggest that PKC and DGK are orchestrated temporally and spatially in the signal transduction.

Animals↗
PubMed2000

HMG-CoA reductase inhibitor induces a transient activation of high affinity nerve growth factor receptor, trk, and morphological differentiation with fatal outcome in PC12 cells.

The present study was aimed at investigating the possible toxicity of simvastatin on a neuronal cell line, PC12 cells. Simvastatin clearly induced a transient morphological differentiation as evidenced by the occurrence of neurite outgrowth with a transient activation of the high affinity nerve growth factor receptor, Trk, but died at 36 h after its addition. Tyrosine autophosphorylation of the Trk protein also disappeared at 36 h after addition. During the morphological differentiation, NGF mRNA expression was upregulated transiently and returned to the basal level at 36 h after addition of simvastatin. These results suggest that simvastatin is neurotoxic and PC12 cells elicited a protective response, involving a transient activation of a Trk-mediated intracellular signal transduction pathway by an autocrine secretion of NGF, although these responses did not persist against pro-apoptotic signals and resulted in an apoptosis of the PC12 cells.

Animals↗
PubMed2000

Phosphoglycerate kinase deficiency: an adult myopathic form with a novel mutation.

The authors report a 36-year-old man with exertional myoglobinuria and muscle cramp without hemolytic anemia or CNS symptoms. They found a deficiency of phosphoglycerate kinase (PGK) activity in muscle and erythrocytes and a 4-base pair deletion in exon 6 of the PGK gene. This mutation may cause a frameshift, yielding an abnormal stop codon in exon 6 by which a truncated PGK protein was produced. This phenotype is caused by a novel mutation of the PGK gene.

Adult↗