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Biomedical subjects

E Amemiya

Publications and source records attributed to E Amemiya.

14 recordsLinked to original sources

Elevation of plasma-soluble tumour necrosis factor receptors (TNF-R) in sarcoidosis.

Two types of receptor for tumour necrosis factor-alpha (TNF-R), the 55-kD receptor (TNF-RI) and the 75-kD receptor (TNF-RII), have been identified. Soluble TNF-RI (sTNF-RI) and soluble TNF-RII (sTNF-RII) can be measured in culture supernatants and biological fluids, and the role of sTNF-R has been suggested. In the present study, we measured plasma sTNF-RI and sTNF-RII levels in 19 patients with active sarcoidosis by ELISA in order to assess the state of both types of receptors in this disease. Both plasma sTNF-RI and sTNF-RII levels in patients with active sarcoidosis were significantly higher than those in normal control subjects. A longitudinal evaluation of plasma sTNF-RI and sTNF-RII levels showed that the magnitude of changes in sTNF-RII was closely related with the clinical course of sarcoidosis. These results suggest that plasma sTNF-RII levels may be useful parameters for monitoring the clinical course of sarcoidosis as well as markers for identifying disease activity.

Adult

TNF-alpha regulates IL-4-induced Fc epsilon RII/CD23 gene expression and soluble Fc epsilon RII release by human monocytes.

We examined the regulatory effects of TNF-alpha on IL-4-induced gene expression of the low-affinity receptor for IgE (Fc epsilon RII/CD23) in human monocytes and IL-4-induced soluble Fc epsilon RII (sFc epsilon RII) release from monocytes. IL-4-induced Fc epsilon RII expression on the surface of monocytes was reduced by TNF-alpha as early as 1 day after culture and the effect of TNF-alpha increased with prolonged culture. The present analysis was designed to examine whether or not TNF-alpha could suppress IL-4-induced Fc epsilon RII mRNA expression and enhanced IL-4-induced sFc epsilon RII release. The addition of TNF-alpha to monocyte cultures with IL-4 significantly reduced Fc epsilon RII expression on the surface of monocytes and significantly increased sFc epsilon RII release from monocytes. Over time, there was an inverse relationship between the disappearance of cell surface Fc epsilon RII and the appearance of sFc epsilon RII in culture supernatants. Fc epsilon RII mRNA expression in monocytes cultured with IL-4 was not affected by TNF-alpha when examined at 6 h after cultivation. When the cells were cultured with TNF-alpha for more than 24 h, however, TNF-alpha down-regulated IL-4-induced Fc epsilon RII mRNA levels. This correlated with the kinetics of down-regulation of IL-4-induced Fc epsilon RII expression on the surface of monocytes by TNF-alpha.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence

Elevation of serum soluble intercellular adhesion molecule-1 (sICAM-1) and sE-selectin levels in bronchial asthma.

Adhesion molecules such as ICAM-1 and E-selectin have been shown to play important roles in the production of allergic inflammation. In the present study, we measured serum soluble ICAM-1 (sICAM-1) and soluble E-selectin (sE-selectin) levels by ELISA in 42 patients with bronchial asthma (22 atopic and 20 non-atopic) during asthma attacks and in stable conditions in order to assess the state of ICAM-1 and E-selectin in allergic inflammation. Both serum sICAM-1 levels and serum sE-selectin levels in sera obtained during bronchial asthma attacks were higher than those in sera obtained in stable conditions. These findings were observed regardless of atopic status. To examine the regulatory mechanism in the elevation of serum sICAM-1 and sE-selectin levels, serum tumour necrosis factor-alpha (TNF-alpha) levels were measured by ELISA. TNF-alpha levels in sera obtained during bronchial asthma attacks were higher than those in sera obtained in stable conditions. There was a correlation between the nature of change in serum TNF-alpha levels and the nature of change in serum sICAM-1 levels or serum sE-selectin levels, though serum TNF-alpha levels did not correlate with serum sICAM-1 levels or serum sE-selectin levels. These results suggest that higher levels of sICAM-1 and sE-selectin during asthma attacks may reflect the up-regulation of ICAM-1 and E-selectin expression in allergic inflammation, and that the soluble form of these adhesion molecules may be useful markers for the presence of allergic inflammation. TNF-alpha is shown to enhance the expression and release of ICAM-1 and E-selectin in vitro, however; the regulatory mechanism in the elevation of serum sICAM-1 and sE-selectin levels remains to be clarified.

Acute Disease

A decreased number of primordial germ cells and the small numbers and reduced sizes of germinal granules in the periodic albino mutant of Xenopus laevis.

Light and electron microscopy were used to examine the cause of the small number of primordial germ cells (PGCs) that were unexpectedly found in periodic albino (a(p)/a(p)) tadpoles of Xenopus laevis. The observations revealed that the volumes of germ plasm were not significantly different between a(p)/a(p) and wild-type eggs and that the germ plasm of ap/ap eggs contained a smaller number of germinal granules than are present in wild-type eggs and the granules were also smaller than in the wild-type eggs. It was concluded that the number of PGCs might be primarily determined by the number and size of germinal granules.

Albinism

Elevated levels of soluble ICAM-1 in sera from patients with bronchial asthma.

We measured the levels of soluble intercellular adhesion molecule-1 (sICAM-1) in sera from patients with bronchial asthma. sICAM-1 levels in sera from atopic asthmatic patients in stable conditions were higher than in normal control subjects. Furthermore, the sICAM-1 levels in sera obtained during bronchial asthma attacks were higher than those in sera obtained in stable conditions. These results suggest that higher levels of sICAM-1 in sera reflect the upregulation of ICAM-1 expression in allergic inflammation.

Adult

Elevation of soluble IL-2 receptor and IL-4, and nonelevation of IFN-gamma in sera from patients with allergic asthma.

To determine whether the predominant in vivo activation of Th1 subset or Th2 subset in peripheral blood occurs in patients with allergic asthma, we measured serum levels of Th1 cell-derived interferon-gamma (IFN-gamma) and Th2 cell-derived interleukin-4 (IL-4). In addition, serum levels of soluble interleukin-2 receptor (sIL-2R) released from activated T cells were measured to determine a potential source of these cytokines. The elevation of serum IL-4 levels and nonelevation of serum IFN-gamma levels were observed in patients with allergic asthma compared with normal control subjects. A significant correlation between serum IL-4 levels and serum sIL-2R levels was observed in these patients. These results suggest that there is allergen-induced in vivo activation of Th2-like cells in peripheral blood of patients with allergic asthma.

Adult