Biomedical subjects

Yoshihiro Fukuda

Publications and source records attributed to Yoshihiro Fukuda.

At least 55 records · Page 3Linked to original sources

PubMed2003

[The present status and problems of Helicobacter pylori eradication therapy with a special reference to gastric cancer].

Since the eradication therapy of Helicobacter pylori(H. pylori) for peptic ulcer was covered by Japanese health insurance at 2000 November, this therapy has been generalized in Japan. However, some problems have cropped up at the time, for example, emergence of clarithromycin resistant bacterium etc. On the other hand, investigation of relation between H. pylori and gastric cancer is making progress. Uemura, et al. demonstrated H. pylori had an important role for gastric carcinogenesis by the elegant prospective study in 2001. Under the present circumstances, the Japanese society of Helicobacter Research has to reconsider the guideline for eradication therapy. In this paper, we would like to state the present status and problems of eradication therapy of the current guideline for eradication therapy, especially focusing on gastric cancer.

Animals↗

PubMed2002

[Helicobacter pylori].

Explore the source record for details and available documents.

Animals↗

PubMed2002

Polymorphisms of the TNF gene and the TNF receptor superfamily member 1B gene are associated with susceptibility to ulcerative colitis and Crohn's disease, respectively.

The importance of tumor necrosis factor (TNF)-alpha and the TNF receptor gene polymorphisms in the etipathogenesis of inflammatory bowel disease (IBD) has not been elucidated. DNA from peripheral blood samples was obtained from 124 patients with Crohn's disease (CD), 106 patients with ulcerative colitis (UC), and 111 unrelated healthy controls. We examined two single nucleotide polymorphisms (SNPs) of the TNF-alpha gene, TNF (-308 G/A and -238 G/A), an SNP of the TNF receptor superfamily member 1A gene, TNFRSF1A(also known as TNFR1), at codon 12 in exon 1 (CCA/CCG), and two SNPs of the 1B gene, TNFRSF1B (also known as TNFR2), (1466 A/G and 1493 C/T). There was a difference in the carrier frequency for haplotype AG (-308 A, -238 G) between UC patients and the controls (OR=4.76, 95% CI=1.53-14.74, P<0.01). We found a significant difference in carrier frequency for haplotype AT (1466 A, 1493 T) of the TNFRSF1B gene between CD patients and the controls (OR=2.13, 95% CI=1.08-4.21, P<0.05). The significance proved to be greater in CD patients with both internal and external fistula (OR=4.8, 95% CI=1.73-13.33, P<0.01), and in those who were poor responders ( n=22) to our treatments, which consisted of nutritional therapy, medical therapy and surgical therapy (OR=9.24, 95% CI=3.37-25.36, P<0.001). This study suggests that one of the genes responsible for UC may be the TNF gene, or an adjacent gene, and that TNFRSF1B gene polymorphisms contribute greatly to the increased onset risk of CD and to the disease behavior.

Adolescent↗

PubMed2002

Comprehensive allelotyping of well-differentiated human hepatocellular carcinoma with semiquantitative determination of chromosomal gain or loss.

Allelic imbalance (AI), which represents certain chromosomal gains or losses, has been described in human hepatocellular carcinoma (HCC), but the impact of AI on the early stage of hepatocarcinogenesis has not been fully clarified. Moreover, no previous allelotype studies have identified the difference in chromosomal gain and loss that results in AI. To resolve these problems, we examined 18 well-differentiated HCCs with comprehensive allelotyping by using 400 microsatellite markers with semiquantitative assessment of chromosomal gain or loss. To detect allelic gain effectively, the cutoff value of the allelic imbalance index was set at 0.70. Each allele showing imbalance was subjected to multiplex PCR with use of a retained allele as an internal control to determine whether the imbalance was the result of chromosomal gain or loss. High frequencies of chromosomal gains were detected at 1q (D1S196-D1S2785, 56%), 5q (D5S647-D5S2027, 44%), 6p (6pter-D6S309, 33%), 7 (7pter-D7S657, 22%), and 8q (D8S514-qter, 44%), whereas chromosomal losses were frequently observed at 1p (1pter-D1S234, 22%), 8p (8pter-D8S549, 44%), and 17p (17pter-D17S921, 28%). The extent of overall chromosomal aberration was closely related to the maximum tumor diameter (P = 0.002) and the presence of hepatitis B surface antigen (P = 0.03). Recurrent chromosomal losses at 1p and 8p and gains at 1q and 8q, even in HCCs with a minimal extent of aberrant chromosomes, indicate that these alterations were critical in the early stage of hepatocarcinogenesis. On the other hand, deletions of 13q and 16q were infrequent and were seen only in the most aberrant cases, which suggested that these were late events.

Aged↗

PubMed2002

IL18 polymorphism is associated with an increased risk of Crohn's disease.

BACKGROUND: The etiology of inflammatory bowel disease, which includes ulcerative colitis and Crohn's disease, has not yet been made clear. However, inflammatory bowel disease is recognized as a multifactorial disease, and innate genetic factors might contribute to the pathogenesis. Cytokine genes are thought to be important in inflammatory bowel disease. Recently, interleukin 18, cloned as a novel proinflammatory cytokine, has been implicated in inflammatory bowel disease, especially Crohn's disease. METHODS: To identify germline mutations in patients with inflammatory bowel disease, the entire coding region of IL18 was examined using a DNA sequencing procedure. RESULTS: No functional mutations were found, but a novel single nucleotide polymorphism (SNP) was identified as TCA/TCC at codon 35. In patients with Crohn's disease, the frequency of TCC allele carriers was significantly higher than in healthy controls (chi2 = 9.35, P = 0.002229, OR = 2.58, 95% CI = 1.39-4.80). Also, the magnitude of the association was more remarkable in females (chi2 = 16.36, P = 0.000052, OR = 8.17, 95% CI = 2.73-24.41). The TCC allele at codon 35 of IL18 may increase the risk for Crohn's disease, especially in females. CONCLUSIONS: IL18 is probably one of several genes that determine susceptibility to Crohn's disease.

Adolescent↗

PubMed2002

Production of chemokines and reactive oxygen species by human neutrophils stimulated by Helicobacter pylori.

BACKGROUND: Bacteria have different characteristics in stimulation of human neutrophils to produce reactive oxygen species (ROS) and chemokines. This study examined the ability of Helicobacter pylori to induce production of ROS and chemokines by human neutrophils. METHODS: H. pylori strains (1.5 x 108 CFU/ml) were cocultured with 5 x 104 neutrophils isolated from healthy subjects. Samples were incubated with human serum with or without IgG antibodies to H. pylori. ROS production was measured using luminol-dependent chemiluminescence (LmCL), and the concentrations of chemokines (IL-8, RANTES, MIP-1alpha and MCP-1) were measured by ELISA. RESULTS: The mean of the highest LmCL (peak height; PH) value stimulated by H. pylori was 3318 in the absence of serum. PH increased to 4687 when incubated with anti-H. pylori antibody-positive sera (p <.001) but antibody-negative sera did not affect LmCL response. The mean final concentration of IL-8 produced in the absence of serum was 142.6 pg/ml. Increased IL-8 production was seen by addition of antibody positive serum (p <.01). IL-8 production was not significantly correlated with production of ROS. On the other hand, H. pylori stimulation did not induce neutrophil production of RANTES, MIP-1alpha or MCP-1. CONCLUSIONS: H. pylori was capable of inducing IL-8 production by human neutrophils, but not C-C chemokines. Production of C-X-C dominant chemokine by neutrophils is consistent with the pathological characteristics of H. pylori-induced gastritis, where persistent neutrophil infiltration is present.

Cells, Cultured↗

PubMed2002

A case report: first case of filtration leukocytapheresis for a patient of aortitis syndrome associated with ulcerative colitis.

An 18-year-old woman was treated with leukocytapheresis (LCAP) for her combined ulcerative colitis (UC) and aortitis syndrome (AS). Because a close relationship between these two diseases has been suspected based on their etiological and/or pathological findings, we had hypothesized that LCAP, which has satisfactory effects on inflammatory bowel disease such as UC and Crohn's disease might be effective for both her UC and her AS. After informed consent, LCAP therapy was performed once a week for a total of 7 times. Endoscopic remission of the UC was observed. Even though there were no significant improvements in her subjective symptoms of AS such as side-neck pain and dizziness, objective evidence of improvement was obtained when the patient's condition was compared before and after LCAP by angiography, angio-magnetic resonance imaging, and the plethysmogram of her fingertips. These results suggest that LCAP may be valuable as a new adjunct therapy for AS.

Adult↗

PubMed2002

Lack of common NOD2 variants in Japanese patients with Crohn's disease.

BACKGROUND & AIMS: Previous studies have linked Crohn's disease (CD) to the pericentromeric region of chromosome 16 (IBD1). Three independent studies of Western populations have recently shown that 3 variants of NOD2, a gene located at 16q12, are associated with susceptibility to CD. Here, we have evaluated the 3 NOD2 variants in Japanese patients to determine whether the gene is also associated with susceptibility to CD in a non-Western population. METHODS: Blood samples were obtained from 350 patients with CD, 272 patients with ulcerative colitis, and 292 healthy controls at 3 hospitals in Japan. DNA was sequenced in the region of the 3 NOD2 variants (C2104T in exon 4, G2722C in exon 8, and 3020insC in exon 11) by genomic polymerase chain reaction followed by direct sequencing. RESULTS: Among the subjects in our 3 study groups, including patients with CD, patients with ulcerative colitis, and healthy controls, none had common NOD2 variants that have been associated with CD in white patients. CONCLUSIONS: These results indicate that genetic variation, which may predispose some human populations to CD, may not be present in other populations and specifically that common variants in NOD2 found in white patients with CD are not associated with CD in the Japanese population.

Adult↗

PubMed2002

Helicobacter pylori does not promote N-methyl-N-nitrosourea-induced gastric carcinogenesis in SPF C57BL/6 mice.

Helicobacter pylori (H. pylori) infection has been acknowledged as a promoter and an initiator for gastric carcinogenesis in experimental models using Mongolian gerbils with H. pylori strains TN2GF4 and ATCC 43504, which have + ve cagA and vacA phenotype s1 / m1. To get more insight into the role of H. pylori in gastric carcinogenesis, we studied the effect of H. pylori SS1, which has + ve cagA and vacA phenotype s2 / m2, on N-methyl-N-nitrosourea (MNU)-induced chemical gastric carcinogenesis using SPF C57BL / 6 mice. Thus, H. pylori SS1 was inoculated 1 week after the completion of MNU treatment to examine the promoting effect of this bacterium. The incidences of polypoid lesions, differentiated adenocarcinomas, and adenomatous hyperplasias were 67% (10 / 15), 47% (7 / 15) and 80% (12 / 15), respectively, in the MNU-alone group. The corresponding figures were 31% (8 / 26), 23% (6 / 26) and 35% (9 / 26) in the MNU + H. pylori group. The incidences of polypoid lesions and adenomatous hyperplasia were significantly different between the groups. Thus, the results indicate that H. pylori SS1 infection reduced susceptibility to chemical gastric carcinogenesis in this model. The discrepancy between the present result and previous results is likely to have been caused by differences in host factors and bacterial factors. Further study of the relationship between gastric carcinogenesis and H. pylori infection is needed.

Animals↗

PubMed2002

Production and application of new monoclonal antibodies specific for a fecal Helicobacter pylori antigen.

The aim of the present study was to establish monoclonal antibodies that could be used to produce a diagnostic test composed of one kind of monoclonal antibody recognizing a fecal Helicobacter pylori antigen. The need to develop such a test arose from disadvantages of the diagnostic test that uses a polyclonal antibody or plural kinds of monoclonal antibodies, such as the lower specificity for H. pylori antigen and the difficulty of reproduction with consistent quality. Mice were immunized with sonicated cells of the coccoid form of H. pylori, and fecal samples from H. pylori-positive subjects were screened by a direct sandwich enzyme immunoassay (EIA) for antibody production from 32 hybridoma clones. The three stable clones produced antibodies (21G2, 41A5, and 82B9) that reacted with the same soluble antigen. Gel filtration chromatography showed that the molecular masses of the cellular antigen and the fecal antigen were the same, 260 kDa. The antigen was labile in response to sodium dodecyl sulfate and heat treatments. A single-step direct sandwich EIA using a single monoclonal antibody, 21G2, was developed. The EIA could detect the antigen in 41 H. pylori clinical isolates and in fecal samples from seven H. pylori-positive subjects. Several kinds of Helicobacter species (Helicobacter felis, Helicobacter hepaticus, Helicobacter mustelae, and Helicobacter cinaedi) except H. pylori, major bacteria in feces (Campylobacter jejuni, Bacteroides vulgatus, Bifidobacterium breve, Bifidobacterium infantis, and Escherichia coli), and fecal samples from six H. pylori-negative subjects showed negative results. These results indicate that the new monoclonal antibodies and the new specific EIA would be useful as a noninvasive method of diagnosis of H. pylori infection.

Animals↗

PubMed2002

Catalase, a specific antigen in the feces of human subjects infected with Helicobacter pylori.

Recently, we reported the production of three new monoclonal antibodies with high specificity for a Helicobacter pylori antigen suitable for diagnosis of H. pylori infection. The aim of the present study was to identify the antigen recognized by these monoclonal antibodies concerning both H. pylori and the feces of human subjects infected with H. pylori. The cellular antigen was purified from an H. pylori cell extract by immunoaffinity column chromatography with the monoclonal antibody as a ligand. The amino-terminal amino acid sequences (eight residues) of the purified antigen and H. pylori catalase were the same. The molecular weights of native and subunit, specific catalase activity, and UV and visible spectra of the purified antigen were in good agreement with those of H. pylori catalase. The human fecal antigens were purified from two fecal samples of two H. pylori-positive subjects by ammonium sulfate precipitation, CM-Sephadex C(50) chromatography, and the same immunoaffinity chromatography used for the H. pylori cellular antigen. The fecal antigens had catalase activity. The amino-terminal amino acid sequences (five residues) of the human fecal antigen and H. pylori catalase were the same. The monoclonal antibodies reacted with the native cellular antigen, but did not react with the denatured antigen, human catalase, and bovine catalase. The results show that the target antigen of the monoclonal antibodies is native H. pylori catalase and that the monoclonal antibodies are able to specifically detect the antigen, which exists in an intact form, retaining the catalase activity in human feces.

Antibodies, Monoclonal↗

PubMed2002

Prognostic impact of multiple allelic losses on metastatic recurrence in hepatocellular carcinoma after curative resection.

Loss of heterozygosity (LOH) on chromosomes 13q, 16q and 17p has been associated with the progression of hepatocellular carcinoma (HCC). To investigate the prognostic impact of such LOH, we examined the metastasis-free survival of curatively resected HCC cases, in whom these LOHs were analyzed. Among the 49 HCC patients examined, the frequency of LOHs was 28% on 13q, 33% on 16q and 40% on 17p. The patients were followed up for metastatic recurrence after surgery and for analysis of the relationship between chromosomal changes and patients' metastasis-free survival. Univariate survival analysis showed the presence of LOH on 16q, 17p and the number of chromosomes with LOH were significantly and negatively associated with metastasis-free survival, indicating that patients with LOH on multiple chromosomes had a poorer prognosis after surgery than those with LOH on a single chromosome or no LOH. Multivariate Cox survival analysis identified the presence of LOH on 16q and the number of chromosomes with LOH as the most significant independent negatively predictive factors for metastasis-free survival. These findings indicate that accumulation of chromosomal changes is associated with metastatic behavior, and that LOH on 16q was the most useful prognostic indicator for metastasis after curative resection of HCC.

Adult↗

PubMed2002

Identification and expression of a rat fatty acid elongase involved in the biosynthesis of C18 fatty acids.

A major part of the palmitic acid (C16:0) generated by fatty acid synthase is converted into stearic acid (C18:0) via carbon chain elongation. Here, we describe the cloning and expression of a rat hepatic enzyme, rELO2, responsible for the elongation of C16:0, presumably at the condensing reaction. Heterologous expression experiments in a yeast, Saccharomyces cerevisiae, demonstrated the elongation activity of rELO2 on C16:0 and to a lesser extent, C18:0 and fatty acids with low desaturation degree. This was distinct from that rELO1, a rat homolog of HELO1, which preferably catalyzed the elongation of mono- and polyunsaturated fatty acids of C16-C20. The Northern analysis showed that the expression of rELO2, but not rELO1, in hepatocytes was activated by the cycles of fasting and refeeding rats on a fat-free diet. Under these conditions, the rELO1 was expressed constitutively in various tissues but the rELO2 transcripts were detected predominantly in liver.

Acetyltransferases↗

PubMed2002