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Y Gon

Publications and source records attributed to Y Gon.

40 records · Page 3Linked to original sources
PubMed1997

N-acetylcysteine attenuates TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in human monocytes.

We have previously shown that tumor necrosis factor-alpha (TNF-alpha) reduces interleukin-4 (IL-4)-induced Fc epsilon RII expression in human monocytes. It has been shown that TNF-alpha activates nuclear transcriptional factors through the generation of reactive oxygen intermediates (ROIs), and antioxidant N-acetylcysteine (NAC) inhibits TNF-alpha-induced activation of nuclear transcriptional factors. Therefore, we hypothesized that TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in monocytes might be mediated through the ROIs-activated mechanism. In the present study, to test our hypothesis, we examined the effect of NAC on TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in human monocytes. NAC attenuated TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression by attenuating TNF-alpha-dependent reduction of Fc epsilon RII mRNA expression. Similarly, the structurally unrelated antioxidant, pyrrolidine dithiocarbamate (PDTC), also effectively attenuated this-reduction. These results indicate that an ROIs-activated and antioxidant-sensitive mechanism might be involved in TNF-alpha-dependent reduction of IL-4-induced Fc epsilon RII expression in monocytes.

Acetylcysteine↗
PubMed1996

[Swyer-James syndrome with bronchial asthma and recurrent spontaneous pneumothorax].

An 18-year-old woman was admitted to our hospital for treatment of the fifth episode of spontaneous pneumothorax. She had a history of repeated pneumonia in childhood and mycoplasma pneumonia at 12 years of age. A chest X-ray film revealed a left-sided pneumothorax, atelectasis of the left upper lobe, and hyperlucency of the left lung. A bronchogram showed poor filling of the peripheral bronchi by contrast medium and mild cylindrical bronchiectasis in the proximal bronchi. Pulmonary arteriography showed small left pulmonary arteries. From these findings, Swyer-James syndrome was diagnosed. This case was complicated by bronchial asthma, with eosinophilia, a high level of IgE, and airway hyperresponsiveness. Atelectasis, multiple bullae, and bronchial asthma had been caused by mycoplasma pneumonia in childhood. Recurrent pneumothorax had been caused by emphysematous changes in the bronchioli and by underdeveloped pulmonary arteries. Surgery to treat the recurrent spontaneous pneumothorax was considered, but was not done because of the risk of relapse and the ventilation-perfusion imbalance due to the Swyer-James syndrome.

Adolescent↗
PubMed1996

Lower serum concentrations of cytokines in elderly patients with pneumonia and the impaired production of cytokines by peripheral blood monocytes in the elderly.

It has been well documented that the immune function declines with age; however, little is known about the monocyte/macrophage function of age. In the present study, we measured the concentrations of granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-1 beta, tumour necrosis factor-alpha (TNF-alpha), IL-8 and monocyte inflammatory protein-1 alpha (MIP-1 alpha) in sera from 15 elderly patients and 22 young patients with pneumonia, in the acute phase and after recovery, by ELISA. In addition, we measured the concentrations of these cytokines in culture supernatants from lipopolysaccharide (LPS)-stimulated peripheral blood monocytes from normal healthy elderly subjects and young subjects in order to clarify the ability of the elderly to produce these cytokines. The concentrations of these cytokines in sera from old patients and in those from young patients obtained in the acute phase were higher than those in sera obtained after recovery phase. However, the concentrations of these cytokines in the acute phase were lower in elderly patients compared with those in young patients. Serum concentrations of cytokines did not appear to be associated with clinical outcome. In the production of these cytokines by monocytes, LPS-stimulated monocytes from healthy normal elderly subjects produced smaller amounts of G-CSF, GM-CSF, IL-1 beta, TNF-alpha, IL-8 and MIP-1 alpha than those from healthy normal young subjects. These results with the impaired production of these cytokines in the elderly may prove, at least in part, the characteristic features of host defence mechanisms of the elderly.

Adult↗