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Y Morita

Publications and source records attributed to Y Morita.

At least 19 recordsLinked to original sources
PubMed2006

No significant difference in neutrophil activation found among three H2RAs.

BACKGROUND: Even with the most effective treatment, Helicobacter pylori eradication is difficult in some patients. Therefore, patients sometimes require acid-suppressive therapy without H. pylori eradication. It has been reported that ranitidine inhibits neutrophil activation, whereas famotidine does not. However, few studies have been published concerning the activation of neutrophils before and after treatment using clinical doses of histamine-2 receptor antagonists in patients with H. pylori infection. AIM: To examine the effects of neutrophil activation after treatment with three different histamine-2 receptor antagonists. PATIENTS: This prospective, open-label, randomised, parallel-group study was conducted. Thirty patients with H. pylori infection were enrolled. These subjects were randomly assigned to receive one of the following treatments: (a) 150 mg ranitidine, (b) 20mg famotidine, or (c) 10 mg lafutidine b.d., for 4 weeks. Before and after histamine-2 receptor antagonist treatment, histological findings, myeloperoxidase activity, and interleukin-8 in the gastric mucosa were evaluated. RESULTS: On the basis of the histological findings between before and after histamine-2 receptor antagonist treatment, no significant differences were found in any groups. Similarly, there were no significant differences in myeloperoxidase activity or interleukin-8 levels. CONCLUSION: In patients with H. pylori, when used at clinical doses, any histamine-2 receptor antagonists can be used without concerning about inhibition of neutrophil activation.

Acetamides↗
PubMed2006

Association study of the tumor necrosis factor-alpha gene and its 1A receptor gene with methamphetamine dependence.

Recent preclinical findings that repeated treatment with methamphetamine (METH) induced an increase in tumor necrosis factor-alpha (TNF-alpha) mRNA in some brain regions and that TNF-alpha blocked METH neurotoxicity and rewarding effects suggest TNF-alpha, a multifunctional pro-inflammatory cytokine, may be involved in METH dependence. We hypothesized that genetic polymorphisms of the TNF-alpha gene and its receptor genes may be associated with vulnerability to METH dependence. Genetic association of -308G>A and -857C>T in the promotor region of the TNF-alpha gene, and 36A>G in exon 1 of the TNF receptor 1A gene (TNFR-SF1A), were analyzed in patients with METH dependence (n = 185) and healthy controls (n = 221) in a Japanese population. No significant association of alleles or haplotypes of the TNF-alpha or TNFR-SF1A genes with METH dependence was found. Neither was any significant association of clinical phenotype with METH dependence found. These results suggest that genetic variations in the TNF-alpha gene and its receptor genes may not be involved in individual vulnerability to METH dependence.

Adult↗
PubMed2006

No association between CART (cocaine- and amphetamine-regulated transcript) gene and methamphetamine dependence.

Cocaine- and amphetamine-regulated transcript (CART) was originally discovered as a peptide that increased in the rat striatum after injection of a psychostimulant drug, such as cocaine or amphetamine, and is suggested to play potential roles in drug dependence. We tested the genetic association between the CART gene and methamphetamine (METH) dependence and/or psychosis. The subjects were 203 patients with METH dependence and 239 age- and gender-matched healthy controls. Two single nucleotide polymorphisms (SNPs) of the CART gene, -156A>G and IVS1 + 224G>A, were examined . There were no significant differences in genotype and allele distributions of the polymorphisms between patients with METH dependence and/or psychosis and controls. Neither were significant differences in subgroups of clinical phenotypes, for example, age at first consumption of METH, latency to onset of psychotic symptoms after the first consumption of METH, prognosis of psychosis after therapy, complication of spontaneous relapse to a psychotic state, or multisubstance abuse status, observed. The present findings suggest that the CART gene may not play a pivotal role in the development of METH dependence and psychosis, at least in a Japanese population.

Adult↗
PubMed2006

Interpretation of scintigraphic findings of oral malignant tumours with a new scanning agent of technetium-99m-hexakis-2-methoxy-isobutyl-isonitrile (Tc-99m-MIBI).

OBJECTIVES: The purpose of this study was to investigate the usefulness of a new scanning agent of technetium-99m-hexakis-2-methoxy-isobutyl-isonitrile (Tc-99m-MIBI) for the diagnosis of malignant tumours of the head and neck. METHODS: Scintigraphy with Tc-99m-MIBI was performed in 19 patients with malignant tumours of the head and neck. Factors of the early and delayed static scans (hot, warm or cold uptake), the early and delayed retention indexes, the blood flow index and the tumour retention index were obtained from Tc-99m-MIBI scintigraphy. Tumour retention indexes were classified into three grades; slightly (>0.9), moderately (0.9-0.8) and severely (0.8>) decreased. Grade of tissue differentiation of tumour (well, moderately or poorly differentiated) and tumour size (T1 approximately T4) were examined using the excised tumour. Scintigraphic indexes and tumour characteristics were compared. RESULTS: The early static scan and tumour size showed a correlation with the blood flow index. However, the delayed static scan did not show any relationship with blood flow index and tumour size. The tumour retention index had a tendency to decrease in malignant tumours, and showed a significant correlation with the grade of tissue differentiation of the tumour. CONCLUSIONS: The tendency of the tumour retention index to decrease in Tc-99m-MIBI scintigraphy showed the malignancy of tumour and would be useful for the diagnosis of malignant tumours of the head and neck.

Adult↗
PubMed2005

Levofloxacin- versus metronidazole-based rescue therapy for H. pylori infection in Japan.

BACKGROUND: The ideal second-line treatment regimens for Helicobacter pylori infection may differ between the areas, countries and races. AIM: The aim was to confirm which was the better regimen for second-line therapy after treatment failure with a standard triple therapy in Japan, a high dosage of levofloxacin- or metronidazole-based therapy. PATIENTS: Sixty outpatients with persistent H. pylori infection after a standard triple therapy were enrolled in this prospective, open-label and randomised trial. METHODS: The subjects were randomly administered levofloxacin (300 mg b.d.)- or metronidazole (500 mg b.d.)-based therapy with lansoprazole (30 mg b.d.) and amoxicillin (1000 mg b.d.) for 7 days, and the cure rates and side effects were analysed. Antimicrobial susceptibility was also examined before second-line therapy using the E-test. RESULTS: Good compliance was obtained without severe side effects in both the groups except for two patients. The cure rates, expressed as intention-to-treat and per-protocol analyses, respectively, were 70.0 and 72.4% in the levofloxacin group, and 96.7 and 100% in the metronidazole group. Each regimen often overcame even clarithromycin-resistant strains. CONCLUSION: Metronidazole-based triple therapy is recommended as second-line therapy in Japan, and levofloxacin-based therapy can be an alternative treatment option.

Adult↗
PubMed2005

Alpha-synuclein-positive structures induced in leupeptin-infused rats.

Abnormal accumulation of alpha-synuclein is regarded as a key pathological step in a wide range of neurodegenerative processes, not only in Parkinson's disease (PD) and dementia with Lewy bodies (DLB) but also in multiple-system atrophy (MSA). Nevertheless, the mechanism of alpha-synuclein accumulation remains unclear. Leupeptin, a protease inhibitor, has been known to cause various neuropathological changes in vivo resembling those of aging or neurodegenerative processes in the human brain, including the accumulation of neuronal processes and neuronal cytoskeletal abnormalities leading to neurofibrillary tangle (NFT)-like formations. In the present study, we administered leupeptin into the rat ventricle and found that alpha-synuclein-positive structures appeared widely in the neuronal tissue, mainly in neuronal processes of the fimbria and alveus. Immunoelectron microscopic study revealed that alpha-synuclein immunoreactivity was located in the swollen axons of the fimbria and alveus, especially in the dilated presynaptic terminals. In addition colocalization of alpha-synuclein with ubiquitin was rarely observed in confocal laser-scan image. This is the first report of experimentally induced in vivo accumulation of alpha-synuclein in non-transgenic rodent brain injected with a well-characterized protease inhibitor by an infusion pump. The present finding suggests that the local accumulation of alpha-synuclein might be induced by the impaired metabolism of alpha-synuclein, which are likely related to lysosomal or ubiquitin-independent proteasomal systems.

Animals↗
PubMed2005

Evaluation of cytomegalovirus-specific cytotoxic T-lymphocytes in patients with the HLA-A*02 or HLA-A*24 phenotype undergoing hematopoietic stem cell transplantation.

Cytomegalovirus-specific cytotoxic T-lymphocytes (CMV-CTL) are essential for the control of CMV reactivation. To monitor the quantity and function of CMV-CTL after hematopoietic stem cell transplantation (HSCT), two CMV epitopes that bind to HLA-A*0201 NLVPMVATV (A*02NLV) and HLA-A*2402 QYDPVAALF (A*24QYD) were evaluated for their immunological potential. Samples from patients with the HLA-A*02 or HLA-A*24 serotype were analyzed by tetramer, intracellular cytokine staining and enzyme-linked immunospot (ELISPOT) assay. There were significantly more A*02NLV-specific CMV-CTL than A*24QYD (23 x 10(6) vs 0.4 x 10(6)/l). The frequency of IFN-gamma-producing cells was also higher upon stimulation with A*02NLV than with A*24QYD (2.5 vs 0.1%/CD8). Furthermore, the magnitude of CMV-CTL expansion was two- to 50-fold when cells were cultured with A*02NLV, while only an insignificant increase was observed in culture with A*24QYD. Although the number of A*24QYD-specific CMV-CTL was very low in most of the HLA-A*24 patients, the incidence of CMV reactivation did not differ between those with HLA-A*02 and HLA-A*24 serotype alone. These results suggest that an epitope other than A*24QYD plays a major role in patients with HLA-A*24. Our study also showed that A*02NLV may be a useful epitope for monitoring CMV-CTL not only in patients with HLA-A*0201 but also in those with the A*0206 genotype.

Adult↗
PubMed2005

Dichotomy of all-trans retinoic acid inducing signals for adult T-cell leukemia.

We previously reported that all-trans retinoic acid (ATRA) inhibits growth in human T-cell leukemia virus type 1 (HTLV-1)-positive T-cell lines and fresh cells from patients with adult T-cell leukemia. However, the mechanism of this inhibition is not clear. In the present study, we observed that NF-kappaB transcriptional activity as well as cell growth decreased significantly in HTLV-1-positive T-cell lines in the presence of ATRA. Furthermore, we observed that ATRA reduced HTLV-1 proviral DNA, HTLV-1 genes (gag, tax, or pol mRNA) using the real-time quantitative polymerase chain reaction. SIL-2R was reduced by ATRA in both protein level (culture supernantant) and mRNA level in HTLV-1-positive T-cell lines. Interestingly, ATRA significantly inhibited RT activity similar to azidothimidine (AZT) in HTLV-1-positive T-cell lines. Moreover, AZT inhibited proviral DNA but not NF-kappaB transcriptional activity, and sIL-2R on HTLV-1; however, ATRA inhibited of NF-kappaB, proviral DNA and sIL-2R on HTLV-1. These results suggested that the decrease in sIL-2R induced by ATRA may be caused by the actions of a NF-kappaB inhibitor acting on the NF-kappaB/sIL-2R signal pathway. These results suggested that ATRA could have two roles, as a NF-kappaB inhibitor and as an RT inhibitor.

Adult↗
PubMed2005

A prospective randomized trial of either famotidine or omeprazole for the prevention of bleeding after endoscopic mucosal resection and the healing of endoscopic mucosal resection-induced ulceration.

BACKGROUND: It has been reported that inhibitors of gastric acid secretion prevent bleeding after endoscopic mucosal resection for mucosal gastric neoplasm. However, uncertain whether an histamine2-receptor antagonist or proton-pump inhibitor is more effective. AIM: To evaluate prospectively the effectiveness of famotidine or omeprazole for ulcer management after endoscopic mucosal resection. METHODS: From July 2003 to October 2004, 57 patients were randomly assigned to famotidine or omeprazole for the management of endoscopic mucosal resection. Both drugs were given intravenously for the first 2 days, thereafter by mouth. The bleeding rates after endoscopic mucosal resection, the effects on the healing of endoscopic mucosal resection-induced ulceration, and cost-benefits were compared. RESULTS: Twenty-eight patients received famotidine and 29 received omeprazole. No significant difference was observed between the two groups in patient characteristics. The bleeding rates after endoscopic mucosal resection were not significantly different (18% vs. 14%) between the groups. Similarly, no differences were seen in the size of the endoscopic mucosal resection-induced ulceration at 1, 30 and 60 days after resection between groups. The total costs of anti-secretory agents demonstrated a significant cost-benefit to those treated with famotidine (10,420 yen vs. 17,782 yen). CONCLUSIONS: Famotidine is suggested as a better alternative to omeprazole for the management of endoscopic mucosal resection, as it showed a clear cost-benefit, and the healing results after endoscopic mucosal resection were similar for the two treatment strategies.

Aged↗
PubMed2005

Influence of proteoglycan contents and of tissue hydration on the frictional characteristics of articular cartilage.

In this work, the hypothesis that water content and substances present on the articular surface play an important role in lubrication through the formation of a layer with a high content of water on the articular surface is analysed. The hydrophilic properties of proteoglycans exposed at the articular surface and hydration of tissue are the main responsible factors for the formation of this layer. The role of the articular surface in the frictional characteristics of articular cartilage was examined using specimens (femoral condyles of pigs) with intact and wiped surfaces tested in intermittent friction tests. Results indicated that the intact condition presented low friction in comparison with the wiped condition. The measured water loss of the articular cartilage after sliding and loading indicated a gradual decrease in the water content as the time evolved, and rehydration was observed after the submersion of unloaded specimens in the saline bath solution. Micrographic analyses indicated the presence of a layer covering the articular surface, and histological analyses indicated the presence of proteoglycans in this superficial layer. The hydration of the cartilage surface layer and proteoglycan in this layer influence lubrication.

Animals↗
PubMed2005

Scintigraphy for interpretation of malignant tumours of the head and neck: comparison of technetium-99m-hexakis-2-methoxyisobutylisonitrile (Tc-MIBI) and thallium-201-chloride (Tl-201).

OBJECTIVES: The purpose of this study was to compare the usefulness of technetium-99m-hexakis-2-methoxyisobutylisonitrile (99Tc(m)-MIBI) and thallium-201-chloride (Tl-201) as scintigraphic agents. METHODS: Dynamic and static scintigraphic imaging with 99Tc(m)-MIBI and Tl-201 were performed on patients with a variety of malignant and benign tumours. Factors of the grade of the static scan, the blood flow index, the early and delayed retention indexes, and the tumour retention index were obtained from the scintigraphy. In addition to these factors, the grade of tissue differentiation and tumour size were evaluated to clarify the difference between 99Tc(m)-MIBI and Tl-201 for the diagnosis of malignant tumours of the head and neck. RESULTS: 99Tc(m)-MIBI accumulation depended upon the blood flow index in the early static scan, but this accumulation did not correlate with tumour size. The accumulation in most subjects decreased in the delayed static scan, and the tumour retention index had a tendency to decrease with the grade of tissue differentiation. Tl-201 accumulation depended upon the blood flow index in the early static scan similar to 99Tc(m)-MIBI, and the accumulation correlated with tumour size, unlike 99Tc(m)-MIBI. The tumour retention index had a tendency to increase with the grade of tissue differentiation. Thus, the tumour retention indexes showed opposite behaviours between 99Tc(m)-MIBI and Tl-201, but they both accurately determined tumour malignancy. CONCLUSIONS: There was no major difference between 99Tc(m)-MIBI and Tl-201scintigraphy with respect to accuracy of diagnosis of malignant tumours of the head and neck. However, 99Tc(m)-MIBI was superior to Tl-201 for small-size tumours and Tl-201 was useful for large-size tumours.

Adenocarcinoma↗
PubMed2005

Expression of permeability-glycoprotein (P-gp) and uptake of technetium-99m-hexakis-2-methoxy-isobutyl-isonitrile (99Tcm-MIBI) in malignant tumour of the head and neck.

OBJECTIVES: The purpose of this study is to estimate the role of permeability-glycoprotein (P-gp) in the technetium-99m-hexakis-2-methoxy-isobutyl-isonitrile (99Tc(m)-MIBI) scintigraphy. METHODS: 71 patients with squamous cell carcinoma (39 patients with well differentiated, 19 with moderately differentiated and 13 with poorly differentiated tumour) were examined. Eighteen of these patients underwent 99Tc(m)-MIBI scintigraphy (early and delayed scans). The tumour retention index, obtained from the ratio of the accumulation of the delayed scan to that of the early scan, was divided into three groups. The immunohistochemical evaluation of P-gp expression was performed in all 71 patients. Levels of the P-gp expression were classified into three grades (score 0, 1 and 2). Correlations among the tumour retention index, the P-gp expression and the tumour tissue differentiation were evaluated. RESULTS: 17 of 18 patients showed a decreasing of the tumour retention index ranging from 0.70 to 0.93 (mean+/-SD=0.850+/-0.071). The tumour retention index showed a statistical correlation with the P-gp expression and the tumour tissue differentiation (chi-squared=7.802>7.779, P=0.10 and 16.835>14.860, P=0.005, respectively). Moreover, there was a statistical correlation between the P-gp expression and the tumour tissue differentiation (chi-squared=14.863>14.860, P=0.005). CONCLUSION: There is a possibility that the P-gp expression is high in the high-grade malignant tumours and P-gp causes the decrease of tumour retention index.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2005

A trial for histopathological subclassification of papillary cystadenoma lymphomatosum by 99Tcm-pertechnetate in a patient with multiple bilateral lesions of the parotid glands.

OBJECTIVES: The purpose of this report was to evaluate the possibility of subclassification of papillary cystadenoma lymphomatosum (PCL) with 99Tc(m)-pertechnetate. METHODS: A patient with multiple bilateral PCLs in the parotid glands was examined by using 99Tc(m)-pertechnetate. RESULTS: All PCLs of the present case, which were diagnosed as the subtype-II histopathologically, showed similar radioactive indexes in scintigraphy (the mean radioactive index = 3.62), although tumours were different in size. The mean radioactive index corresponded well with that from four cases of subtype-II of our previous report (the mean radioactive index = 3.84). CONCLUSIONS: The results of the present report suggest a possibility of histopathological subclassification of PCLs into subtypes by 99Tc(m)-pertechnetate scintigraphy.

Adenolymphoma↗
PubMed2004

Ahl3, a third locus on mouse chromosome 17 affecting age-related hearing loss.

Genetic variation in humans probably plays a role in determining the range of individual susceptibility to age-related hearing loss (AHL), but no contributing loci have been identified because of the difficulties of dissecting complex traits in humans. This paper reports mapping of an AHL locus using a panel of consomic mice between C57BL/6J (B6) and MSM strains, which covered more than a half of chromosome sets. B6 strain exhibited AHL beginning at 10 months of age whereas MSM strain, derived from Japanese wild mice, had normal hearing throughout life. Individuals in the panel were examined with auditory brainstem response (ABR) at various months of age, revealing that one particular strain (B6-Chr17(MSM)) substituting the chromosome 17 with the MSM-derived one showed a prominent resistance, having still good hearing at 18 months of age. Subsequent mapping using 89 individuals in the cross between B6-Chr17(MSM) and B6 was performed, which showed a significant association of ABR thresholds with loci in the vicinity of D17Mit119. These results show a novel AHL-resistant locus, designated as Ahl3, on the chromosome 17.

Age Factors↗
PubMed2004

Repair of articular cartilage defects in rabbits using CDMP1 gene-transfected autologous mesenchymal cells derived from bone marrow.

OBJECTIVE: Cartilage-derived morphogenetic protein 1 (CDMP1), which is a member of the transforming growth factor-beta superfamily, is an essential molecule for the aggregation of mesenchymal cells and acceleration of chondrocyte differentiation. In this study, we investigated whether CDMP1-transfected autologous bone marrow-derived mesenchymal cells (BMMCs) enhance in vivo cartilage repair in a rabbit model. METHODS: BMMCs, which had a fibroblastic morphology and pluripotency for differentiation, were isolated from bone marrow of the tibia of rabbits, grown in monolayer culture, and transfected with the CDMP1 gene or a control gene (GFP) by the lipofection method. The autologous cells were then implanted into full-thickness articular cartilage defects in the knee joints of each rabbit. RESULTS: During in vivo repair of full-thickness articular cartilage defects, cartilage regeneration was enhanced by the implantation of CDMP1-transfected autologous BMMCs. The defects were filled by hyaline cartilage and the deeper zone showed remodelling to subchondral bone over time. The repair and reconstitution of zones of hyaline articular cartilage was superior to simple BMMC implantation. The histological score of the CDMP1-transfected BMMC group was significantly better than those of the control BMMC group and the empty control group. CONCLUSION: Modulation of BMMCs by factors such as CDMP1 allows enhanced repair and remodelling compatible with hyaline articular cartilage.

Animals↗