Search PubMed⌕ Search

Biomedical subjects

Y Fukuda

Publications and source records attributed to Y Fukuda.

At least 109 records · Page 6Linked to original sources
PubMed2001

[The history of Helicobacter pylori].

Histological and ultrastructural studies of gastric mucosa with spiral bacteria had been published at the Royal Perth Hospital of Western Australia in 1979. The pathologist Warren correlated them with inflammation. In 1981, Marshall was training in internal medicine. Warren, Marshall and Goodwin started culture of bacteria, but spiral bacteria were not cultured. The 35th culture was left during the Easter holiday, and after 5 days 1-mm transparent colonies were seen on the plate. Since discovery Helicobacter pylori(H. pylori) have continued to fascinate and challenge doctors and scientists for 18 years to come. In 2000, triple therapy with PPI, Amoxicillin and clarithromycin was approved for treatment of peptic ulcer disease in Japan.

Helicobacter Infections↗
PubMed2001

Early augmentation of interleukin (IL)-12 level in the airway of mice administered orally with clarithromycin or intranasally with IL-12 results in alleviation of influenza infection.

The protective role of interleukin (IL)-12 against influenza infection was assessed by analyzing the efficacies of orally administered clarithromycin (CAM) as an immunomodulator and intranasal administration of recombinant IL-12 in intranasally influenza virus-infected mice. In infected mice, CAM at 20 mg/mouse/day significantly elevated the levels of IL-12 and interferon-gamma on days 2 and 3, respectively, after infection in the bronchoalveolar lavage fluid (BALF), but the levels in the sera were not affected. The levels of IL-4, -6, and -10 were not significantly affected in the sera and BALF. Corresponding with the local elevation of IL-12 level, CAM reduced virus yield and the number of infiltrated cells in the BALF, the severity of pneumonia, and mortality of the treated mice. The potential activity of CAM as an experimental immunomodulator was verified at a dose of 20 mg/mouse/day. Intranasal administration of the optimal dose (20 ng/mouse) of IL-12 on day 2 significantly reduced virus yield in the BALF after infection. The loss of body weight was significantly suppressed by IL-12 administration. The local elevation of IL-12 level at the optimal dose and timing in influenza infection was confirmed to be effective in alleviating the influenza infection in mice treated with the two different ways. Thus, the augmentation of IL-12 production or administration of supplementary IL-12 in the respiratory tract was essential in reducing virus yield in the early phase of influenza and may be crucial for recovery from influenza infection.

Administration, Intranasal↗
PubMed2001

Japan-specific subtype of hepatitis C virus genotype 1b, J subtype, has relatively low pathogenicity.

The prognostic implication of viral genotype 1b for hepatitis C virus (HCV) infection has been controversial, possibly due to the pathogenetic heterogeneity of genotype 1b. We analyzed two newly delineated subtypes of HCV genotype 1b subtypes with respect to progression of liver disease. Patients with chronic HCV 1b infection (113 total, including 18 with chronic persistent hepatitis, 60 with chronic active hepatitis, 19 with cirrhosis, and 16 with hepatocellular carcinoma with cirrhosis) were studied to elucidate the factors associated with progression of liver disease. Factors evaluated included sex, age at diagnosis, blood transfusion history, and HCV genotype 1b subtype (W subtype or J subtype). W subtype was identified more often in association with chronic active hepatitis than with chronic persistent hepatitis (P = 0.0089), and more often in patients with cirrhosis than in those without (P = 0.0044). The age-, sex-, and transfusion history-adjusted odds ratios with respect to histological activity and presence of cirrhosis for W subtype compared to J subtype were 6.966 (1.856 to 26.145) and 6.397 (1.506 to 27.179), respectively. Age at diagnosis was the most important risk factor for predicting development of cirrhosis and carcinoma. In conclusion, the W subtype of HCV 1b is associated closely with histologically active disease and development of cirrhosis, whereas the Japan-specific J subtype has relatively low pathogenicity. HCV genotype 1b, therefore, is heterogeneous in its pathogenicity.

Adult↗
PubMed2001

[A case of bronchiolitis obliterans: auscultation leading to accurate diagnosis].

This is a case of a 31-year-old man with a history of common cold. He had been suffering from productive cough and dyspnea on exertion. Squawks were heard through auscultation, and hyperinflation was also observed in his chest radiograph. Bronchiolitis was first suspected as a result of HRCT and TBLB. He was then treated with CAM for six months, but his symptoms showed little improvement. So we evaluated his squawks objectively by phonopneumograph, performed video assisted thoracoscopic surgery and diagnosed his illness as constrictive bronchiolitis. Based on the examinations, PSL therapy was applied to his case, which contributed improving his condition remarkably. The significance of this case is that proper auscultation led to the accurate diagnosis.

Adult↗
PubMed2000

Immunologic dynamics in hemophiliac patients infected with hepatitis C virus and human immunodeficiency virus: influence of antiretroviral therapy.

Infection with hepatitis C virus (HCV) or human immunodeficiency virus (HIV) or both is common in hemophiliac patients due to putative transmission through clotting factor concentrates. Recently, highly active antiretroviral therapy (HAART) has been found to markedly improve viremia and immunologic parameters in patients infected with HIV. This report considers interactions between these viral infections, the immune system, and antiretroviral therapy. A total of 130 male hemophiliac patients were grouped according to type of viremia (HCV, HIV, both, or neither). Along with 30 healthy men age-matched to viremic patients, these groups were compared with respect to viral load and immunologic parameters. Thirty-five patients treated as above for HIV were serially followed up. HCV infection was associated with reduced peripheral B-cell and CD4(+)-cell counts and with increased serum IgG and IgM levels, whereas HIV infection was associated with reduced peripheral CD4(+)-cell counts and increased serum IgG and IgA levels. In patients with both viruses, HCV and HIV RNA load correlated inversely with peripheral B-cell and CD4(+)-cell counts, respectively. HAART reduced levels of both viruses in the blood. Of the 25 patients with both viruses, HAART eliminated HCV in 2. In conclusion, immunologic dynamics differed between hemophiliac patients infected with HCV, HIV, or both. The relative dynamics of HCV viral load, peripheral B-cell count, and serum IgM level were similar to those of HIV viral load, CD4(+)-cell count, and serum IgA. (Blood. 2000;96:4293-4299)

Adolescent↗
PubMed2000

Tau neutrinos favored over sterile neutrinos in atmospheric muon neutrino oscillations.

The previously published atmospheric neutrino data did not distinguish whether muon neutrinos were oscillating into tau neutrinos or sterile neutrinos, as both hypotheses fit the data. Using data recorded in 1100 live days of the Super-Kamiokande detector, we use three complementary data samples to study the difference in zenith angle distribution due to neutral currents and matter effects. We find no evidence favoring sterile neutrinos, and reject the hypothesis at the 99% confidence level. On the other hand, we find that oscillation between muon and tau neutrinos suffices to explain all the results in hand.

Journal Article↗
PubMed2000

Use of conventional or replicating nucleic acid-based vaccines and recombinant Semliki forest virus-derived particles for the induction of immune responses against hepatitis C virus core and E2 antigens.

Replicating and nonreplicating nucleic acid-based vaccines as well as Semliki Forest-recombinant Viruses (rSFVs) were evaluated for the development of a vaccine against hepatitis C virus (HCV). Replicating SFV-DNA vaccines (pSFV) and rSFVs expressing HCV core or E2 antigens were compared with classical CMV-driven plasmids (pCMV) in single or bimodal vaccine protocols. In vitro experiments indicated that all vaccine vectors produced the HCV antigens but to different levels depending on the antigen expressed. Both replicating and nonreplicating core-expressing plasmids induced, upon injection in mice, specific comparable CTL responses ranging from 10 to 50% lysis (E:T ratio 100:1). Comparison of different injection modes (intramuscular versus intraepidermal) and the use of descalating doses of DNA (1-100 microgram) did not show an increased efficacy of the core-SFV plasmid compared with the CMV-driven one. Surprisingly, rSFVs yielded either no detectable anticore CTL or very low anti-E2 antibody titers following either single or bimodal administration together with CMV-expressing counterparts. Prime-boost experiments revealed, in all cases, the superiority of DNA-based only vaccines. The anti-E2 antibody response was evaluated using three different assays which indicated that all generated anti-E2 antibodies were targeted at similar determinants. This study emphasizes the potential of DNA-based vaccines for induction of anti-HCV immune responses and reveals an unexpected and limited benefit of SFV-based vaccinal approaches in the case of HCV core and E2.

Animals↗
PubMed2000

Isolation and characterization of a novel human gene (NESH) which encodes a putative signaling molecule similar to e3B1 protein.

Using a conventional cloning technique, a novel full-length cDNA was isolated and sequenced from a human placental cDNA library. This cDNA consists of 2129 bp and has a predicted open reading frame encoding 366 amino acids. It possesses a Src homology 3 (SH3) motif, proline-rich region, serine-rich region and no catalytic domain, suggesting that it seems to be a signaling protein most similar to e3B1, an eps8 SH3 binding protein. PCR-based mapping with both a monochromosomal hybrid panel and radiation hybrid cell panels placed the gene to human chromosome 17q21.3 near the marker D17S1795.

Adaptor Proteins, Signal Transducing↗
PubMed2000

Identification of a novel gene, GASC1, within an amplicon at 9p23-24 frequently detected in esophageal cancer cell lines.

In a recent study, we identified frequent amplification of DNA copy number at chromosome 9p23-24 in cell lines derived from esophageal squamous cell carcinomas (ESCs), using comparative genomic hybridization. Because amplified regions often harbor oncogenes and/or other tumor-associated genes, and because 9p23-24 amplification had been reported in various other types of cancers, we used fluorescence in situ hybridization and Southern blot analysis to map the 9p23-24 amplicon. We then screened target genes/transcripts present within this amplicon by Northern blotting. With this strategy, we successfully cloned a novel gene, designated gene amplified in squamous cell carcinoma 1 (GASC1), that was amplified and overexpressed in several ESC cell lines. The deduced amino acid sequence of GASC1 contains two PHD-finger motifs and a PX domain. PHD-finger motifs are found in nuclear proteins that participate in chromatin-mediated transcriptional regulation and are present in a number of proto-oncogenes. Our findings suggest that overexpressed GASC1 may play an important role in the development and/or progression of various types of cancer including ESC.

Amino Acid Sequence↗
PubMed2000

A new intraretinal recording system with multiple-barreled electrodes for pharmacological studies on cat retinal ganglion cells.

To overcome technical difficulties associated with in vivo intraretinal recordings of cat retinal ganglion cells (RGCs) with multiple-barreled electrodes, we developed a new guide-trocar system that consisted of a small-diameter and large-diameter pipes. We also improved the method to construct tungsten-in-glass multiple-barreled electrodes suitable for intraretinal recording from RGCs. Only the small-diameter pipe was inserted into the eye ball through the sclera, through which only the taper part of a multiple-barreled electrode pass. The large-diameter pipe stably held the electrode at its trunk and remained outside the eye ball. Insertion of only the small-diameter pipe minimized damages in the eye ball and prevented the eye ball movements while positioning the electrode. The system allowed us to keep the recordings stable for more than 1 h. Iontophoretically applied L-glutamate successfully activated RGCs of both X and Y types in the cat retina.

Animals↗
PubMed2000

P2 Purinoceptor expression and functional changes of hypoxia-activated cultured rat retinal microglia.

P(2) purinoceptors appear to modulate microglia function, but their role in hypoxic microglia has not been investigated. We examined in postnatal rat retinal microglia cultured under hypoxic (1% oxygen) condition, their P2 expression, proliferation and cytokine release in the presence or absence of the P2 receptor agonists and antagonists. Fura-2 fluorescence measurements of intracellular Ca(2+) rises to P2 receptor agonists and antagonists indicated that both P(2U) and P(2Z) were expressed in hypoxic microglia. Hypoxia induced BrdU incorporation and release of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) as well. The P(2U) agonist, UTP, maintained the BrdU incorporation, whereas the P(2Z) agonist, BzATP, suppressed it, but significantly enhanced IL-1beta and TNF-alpha release, suggesting that the P(2U) response may underlie the mitotic activity, and that of P(2Z), the IL-1beta and TNF-alpha release of hypoxia-activated microglia.

Animals↗
PubMed2000

Preoperative treatment with tegafur suppositories enhances apoptosis and reduces the intratumoral microvessel density of human colorectal carcinoma.

BACKGROUND: This study examined the effect of tegafur, a depot of 5-fluorouracil, in human colorectal carcinomas in terms of apoptosis, cell proliferation, and expression of p53 gene and angiogenesis-related molecules. METHODS: A total of 32 patients with colorectal carcinoma were divided into 2 groups; 20 patients received tegafur suppositories (TS) at 1 g/day for 14 days before surgery, and 12 patients did not receive any chemotherapy. Surgically removed specimens were examined immunohistochemically for Ki-67, CD34, p53, p21, Bax, vascular endothelial growth factor (VEGF), and thymidine phosphorylase (dThdPase). Apoptotic tumor cells were visualized by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxigenin nick-end labeling (TUNEL) procedure. RESULTS: The mean percentage of apoptotic index (AI) was 6.9 +/- 1.2 in the 20 TS-treated tumors and 4.4 +/- 1.0 in the 12 nontreated tumors (P < 0.001). In contrast, the mean percentage of Ki-67 labeling index (KI) became significantly lower in the former group (P < 0.05). The frequency of p21 expression was significantly higher in the TS-treated group than in the nontreated group (P < 0.05), whereas no difference was detected in p53 and Bax expression between the two groups. The mean intratumoral microvessel density was 47.8 +/- 19.8 in the TS-treated tumors and 66.8 +/- 16.5 in the nontreated tumors (P < 0.01). The frequency of dThdPase expression, but not of VEGF expression, became significantly lower with the TS treatment. p53 expression did not correlate with AI, KI, IMV density, or the expression of VEGF, p21, or Bax, except for dThdPase, which was significantly higher in the 18 p53 positive tumors (P < 0.05). CONCLUSIONS: Preoperative TS treatment enhances apoptosis and suppresses angiogenesis of colorectal carcinomas in a p53-independent manner.

Aged↗
PubMed2000

Effect of human plasma-type platelet-activating factor acetylhydrolase in two anaphylactic shock models.

The effect of human recombinant plasma-type platelet-activating factor (PAF) acetylhydrolase was examined in two murine models, PAF-induced death and active anaphylactic models. In the PAF-induced death model where mice were injected intravenously with 40 microg/kg of PAF, the administration of PAF acetylhydrolase reduced mortality in a dose-dependent manner, showing complete prevention of mortality at 1.0 mg/kg. Myeloperoxidase activity, the marker for neutrophils, was increased in the lung by PAF injection, and the PAF acetylhydrolase treatment significantly reversed the increase in myeloperoxidase activity. As in the PAF-induced model, PAF acetylhydrolase also decreased mortality in the active anaphylactic shock model where bovine serum albumin was injected intravenously to mice previously immunized with bovine serum albumin. The protective effect of PAF acetylhydrolase on mortality in this model was significant at 1.0 mg/kg. These results suggest that PAF is an important mediator in the lethality of systemic anaphylaxis, and that PAF acetylhydrolase may be beneficial for treatment of anaphylactic shock.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗