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Biomedical subjects

T Yabana

Publications and source records attributed to T Yabana.

At least 37 records · Page 2Linked to original sources
PubMed1995

Mucosal immune response to Helicobacter pylori and cytotoxic mechanism.

BACKGROUND: Helicobacter pylori is widely accepted as a major pathogen in gastritis. The histologic features of H. pylori gastritis are the numerous infiltrating mononuclear cells (MNCs) and neutrophils. It is not clear what role the infiltrating MNCs and neutrophils play in H. pylori gastritis. METHODS: In this study, we have established enzyme-linked immunospot (ELISPOT) assay for the measurement of H. pylori antibody-producing cells in gastric mucosa. RESULTS: Using ELISPOT assay, we found that H. pylori-specific IgA-producing cells as well as IgG-producing cells were distributed in gastric mucosa. These H. pylori-specific antibodies in gastric mucosa and neutrophils are responsible for the induction of cytotoxic effect to cultured Vero cells. CONCLUSIONS: These observations suggest that a mucosal immune response specific to H. pylori is closely associated with the pathogenesis of gastritis.

Animals↗
PubMed1994

The effect of the immune response to Helicobacter pylori in the development of intestinal metaplasia.

AIM: To determine whether cytotoxic Helicobacter pylori antibodies occur in gastric mucosa, and whether these antibodies contribute to the development of intestinal metaplasia. MATERIALS AND METHODS: The number of mononuclear inflammatory cells, which specifically produce immunoglobulin (Ig)G and IgA antibodies, was investigated by using an enzyme-linked immunospot assay and the fraction of mononuclear inflammatory cells determined in gastric biopsy specimens from 34 subjects with H. pylori infection. Assays for the cytotoxicity of H. pylori antibodies were performed on cultured Japanese green monkey kidney (Vero) cells and by in vitro tests. RESULTS: The number of IgG and IgA antibody-producing cells was positively correlated with the degree of inflammation of the gastric mucosa. However, the number of IgG antibody-producing cells was lower in subjects with intestinal metaplasia than in those without. This was not the case for IgA. Significant cytotoxic damage was observed in Vero cells in vitro when incubated in a solution containing the H. pylori IgG antibody, antigen and polymorphonuclear leukocytes. No cytotoxicity was seen with the IgA antibody or with the antigen or polymorphonuclear leukocytes alone. CONCLUSIONS: H. pylori infection is associated with the appearance of immunocompetent mononuclear cells in gastric mucosa. These cells produce H. pylori antibodies of the IgG class which are capable of causing cytotoxic damage in the epithelial cells, obviously through activation of polymorphonuclear leukocytes by antibody-antigen complexes. The occurrence of these cells is inversely related to intestinal metaplasia, suggesting that they may be involved in the processes of epithelial damage leading to the appearance of intestinal metaplasia.

Adult↗
PubMed1994

[Clinical problems of alcoholics with a history of methamphetamine abuse].

The authors studied the clinical problems of alcoholics with a history of methamphetamine abuse as compared with alcoholics with no history. The samples were in- and out-patients of Kanagawa Prefectural Center of Psychiatry, Serigaya Hospital, from January to December 1992. This study covered 26 alcoholics who had abused methamphetamine from 1 to 40 years before, with an average age at admission was 43.5 years. This compared with a 50.4 year average for 89 alcoholics who had no history of methamphetamine abuse. Hepatitis C antibodies (HCVAb) were significantly more commonly observed in ex-methamphetamine abusers than in non-abusers (73.1% vs. 18.0%). Hepatitis B antigens (HBsAg) were no more common among abusers than non-abusers (0% vs. 2.2%). Blood transfusion history tended to be greater in ex-methamphetamine abusers than non-abusers (38.5% vs. 29.2%) but the difference did not reach conventional levels of statistical significance. Ex-abusers often wore tattoos (23.1%) whereas none of the non-abusers did, a significant difference. Significantly more ex-methamphetamine abusers were diagnosed as suffering from alcoholic hallucinosis than non-abusers (42.3% vs. 7.9%). As more ex-methamphetamine abusers than non-abusers were living alone (61.5% vs. 31.5%), were on welfare (61.5% vs. 23.8%), and living in skid-row areas (15.4% vs. 5.6%), the authors concluded that their living conditions were unstable.

Adult↗
PubMed1993

Detection of a circulating antibody against a peptide epitope on a mucin core protein, MUC1, in ulcerative colitis.

This study aims at clarifying whether the humoral immune response to the tandem repeat domain of MUC1 can be induced or not in vivo. The expression of MUC1 mRNA in the colon was revealed by Northern blot analysis, and cDNA cloning of an extracellular tandemly repeated domain of MUC1 was then performed to prepare the recombinant MUC1 protein. A cDNA clone coding for ten repeat domains was ligated into an expression vector in prokaryotes, resulting in a recombinant protein which could react with the MAb MUSE11 against an adenocarcinoma-associated antigen whose epitope has been shown to be localized in the tandem repeat domain on MUC1. The reactivity of sera from patients with ulcerative colitis with the recombinant protein was evaluated by SDS-PAGE and Western blot analysis to detect the antibodies against this tandem repeat domain. Five out of 19 serum samples tested positive, and these reactions were totally inhibited by MAb MUSE11, suggesting that the epitope recognized by these antibodies in sera is almost identical to that recognized by MAb MUSE11. The data represent the first demonstration of antibody production against a peptide epitope of the tandem repeat domain of MUC1.

Adolescent↗
PubMed1993

Gastric non-Hodgkin's lymphoma associated with Behçet's disease.

The first case of primary gastric lymphoma associated with Behçet's disease is reported. A 43-year-old woman, who had been treated for Behçet's disease for 15 years, was diagnosed as low-grade and small lymphocytic malignant lymphoma of the stomach. Although the patient had been treated for Behçet's disease, chemotherapy was performed and a complete remission of gastric lymphoma was achieved. The literature regarding the association of malignant diseases with Behçet's disease is briefly reviewed.

Adult↗
PubMed1993

Chronic encapsulated intracerebral hematoma associated with angiographically occult arteriovenous malformation--case report.

A 34-year-old female presented with a rare chronic encapsulated intracerebral hematoma associated with an angiographically occult arteriovenous malformation. A neovascularized fibrous capsule containing various stages of intracerebral hematoma formation was removed. These unusual entities mimic brain tumors or abscesses because of gradual growth and slowly progressive neurological deficits. Repeated bleeding or exudation from the capillaries of the capsule may allow expansion of the chronic encapsulated intracerebral hematoma.

Adult↗