Ataru Kuroiwa

St.Mary's Hospital (Fukuoka - Japan), Hukuoka, Fukuoka, Japan

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Publications (11)21.52 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Neuroinflammation in Parkinson's disease (PD) involves activation of microglia, participation of several inflammatory cytokines, prostaglandins, complement and systemic activation of natural killer (NK) cells, suggesting that innate immunity has a role in the pathogenesis of this disease. In this study, we examined NK activity and the expression of its regulatory molecules in peripheral lymphocytes of PD patients and compared the results with those of healthy controls. Expression of the inhibitory NKG2A receptors was significantly lower in PD, causing PD patients to be susceptible in a condition for NK activation after NK cells bind to target cells via these receptors.
    Parkinsonism & Related Disorders 02/2008; 14(1):46-51. · 3.27 Impact Factor
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    ABSTRACT: Immune reaction-related inflammation may be important in the pathogenesis of Parkinson disease (PD). To elucidate peripheral immunologic alterations in PD, we characterized extended peripheral T-lymphocyte populations in 33 patients with PD and 34 normal subjects. Patients with PD had significantly decreased CD4+:CD8(+)T-cell ratios (P<0.001), fewer CD4(+)CD25(+)T cells (P<0.01), and significantly increased ratios of IFN-gamma-producing to IL-4-producing T cells (P<0.001). The characteristics of predominant expression of CD8(+)T cells, depletion of CD4(+)CD25(high) cells, and a shift to a T(H)1-type immune response in the peripheral immune system in PD patients may reflect an immune reaction-associated inflammatory process in the brain.
    Parkinsonism & Related Disorders 01/2006; 11(8):493-8. · 3.27 Impact Factor
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    ABSTRACT: Hochu-ekki-to (HOT) has long been used for treatment of the elderly complaining of severe weakness. In this study, we examined its immunopharmacological effect on 16 elderly patients, aged 76.5 years on average and complaining of general fatigue. They were administered orally 7.5 g of HOT every day for at least 120 days (4 months), which provided them with a noticeable improvement of their physical condition. From the immunological point of view, during the observation period, the total number of circulating leukocytes remained unchanged, as well as the ratios between CD3+T- and CD20+B-cells and between CD4+T- and CD8+T-cells. However, as verified on day 30 as well as on day 120 after the administration of HOT, the activity of NK against K562 target cells was significantly enhanced. Also, on days 30 and 120, there was a significant increase in serum IFN-γ level which is thought to be associated with NK activity. From these results, it may be concluded that the oral administration of HOT to the elderly may help them ameliorate, at least partially, their immunological capacity as well as their physical condition.
    Geriatrics & Gerontology International 09/2004; 4(s1):S118 - S120.
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    ABSTRACT: In general, the elderly show a significant age-related decline in their immune response, thus leading to an increased vulnerability to infections or to an increase in the occurrence of malignant tumors. In this study, we examined the effect of Hochu-ekki-to (HOT or TJ-41) on the immunological capacity of the elderly. A group of elderly patients complaining of general fatigue or weakness were orally administered 7.5 g of HOT everyday for at least 120 days (4 months), whereas another group of aged patients mainly complaining of a loss of appetite were daily given 7.5 g of Anchu-san (TJ-5) during the same period and served as a control group. From the immunological point of view, the total number of circulating leukocytes remained unchanged, during the observation period both in the HOT and Anchu-san groups, as well as the ratios between CD3(+) T and CD20(+) B cells and between CD4(+) T and CD8(+) T cells. In addition, no differences were observed in the expression of CD25 antigen, which represents an activated state of T cells. However, as verified on day 30 as well as on day 120 after the administration of HOT, the natural killer (NK) activity against K562 target cells was significantly enhanced, in comparison to the results on day 0 in the HOT group, as well as to that activity on days 0, 30 and 120 in the Anchu-san group. In addition, on days 30 and 120 in the HOT group, there was a significant increase in the serum IFN-gamma level, which is thought to be associated with the NK activity, whereas no significant changes in that level were observed in the Anchu-san group, during the study period. From these results, it may be concluded that the administration of HOT to elderly people may help them improve, at least to some degree, their immunological capacity.
    International Immunopharmacology 03/2004; 4(2):317-24. · 2.42 Impact Factor
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    ABSTRACT: The purpose of this study was to examine the relationship between active compared to inactive lifestyles and immunocompetence in men. Subjects, all male volunteers, regularly exercising moderately were separated into three age groups: young (20-39 years), middle-aged (40-59 years) and elderly (more than 60 years). Age-matched sedentary male subjects served as controls in each group. Immunological assessments were, total leucocyte count, lymphocyte subpopulation counts, natural killer cell activity and neutrophilic phagocytosis. Total leucocyte and T-cell (CD3+) counts were not significantly different among the groups. Among T-cell subsets, there was a slight increase in helper T-cell (CD3+CD4+) and a decrease in cytotoxic/suppressor T-cell (CD3+CD8+) concentrations in the older sedentary subjects, resulting in an age-associated significant increase in the CD4:CD8 ratio among those control groups. However, among the exerciser groups, no such increase and decrease in the T-cell subpopulations or an age-related increase of the CD4:CD8 ratio were observed. Considering the components of innate immunity, the concentration of NK-cells (CD16+CD56+) significantly increased in the elderly exercisers, compared to that of the age-matched control subjects, or of the young group. The phagocytotic activity of neutrophils showed an age-associated decline, but of lesser degree in the elderly exercisers than in the elderly controls. Taken together, these results suggest that habitual and moderate training in later life is associated with a lesser age-related decline in certain aspects of circulating T-cell function and innate immunity.
    Arbeitsphysiologie 01/2002; 86(2):105-11. · 2.66 Impact Factor
  • N Okabe, A Kuroiwa, A Nagayama
    Digestive Diseases and Sciences 02/2000; 45(1):32-3. · 2.26 Impact Factor
  • Nobuo Okabe, Ataru Kuroiwa, Ariaki Nagayama
    Digestive Diseases and Sciences 12/1999; 45(1):32-33. · 2.26 Impact Factor
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    ABSTRACT: Background. IgA nephropathy is the commonest type of glomerulonephritis. Recent studies have shown a decrease in the expression of HLA class I antigens on peripheral blood mononuclear leukocytes (PBML) from patients with HLA class II-associated autoimmune diseases. In this study, the expression of HLA molecules on T cells from patients with IgA nephropathy was examined in order to investigate the immunological events contributing to the pathogenesis of this disorder. Methods. Thirty Japanese patients with IgA nephropathy were studied. Nine patients with membranous nephropathy and 21 sex- and age-matched healthy individuals were enrolled as controls. Heparinized PBML with or without stimulation by an anti-CD3 monoclonal antibody were analyzed in regard to the expression of HLA-class I, HLA-DR, CD4, CD8, CD11a, CD11b, and CD56, by two-color fluorescence flow cytometry. Results. The expressions of HLA-class I, HLA-DR, CD11a, CD11b, and CD56 on resting CD3-positive, CD4-positive, CD8-positive, or CD20-positive cells from patients with IgA nephropathy were found to be comparable with those from the controls. However, after stimulation by anti-CD3 antibody, the expression of HLA-DR on CD4-positive cells from these patients was significantly higher than that from the controls. Further, the expression of HLA-DR on CD4-positive cells from patients with proteinuria of more than 1 g/day was much higher than that in patients with proteinuria of less than 1 g/day. Conclusions. In this study, the expression of HLA-DR on stimulated Th cells from IgA nephropathy patients was shown to be significantly higher than the expression in the stimulated T cells from the controls. This finding suggests that Th cells may acquire antigen-presenting activity by HLA-DR expression, present antigens to other Th cells, promote B cells to produce antibodies, and, presumably, lead to the development of IgA nephropathy.
    Clinical and Experimental Nephrology 07/1999; 3(3):186-191. · 1.25 Impact Factor
  • Medicine and Science in Sports and Exercise - MED SCI SPORT EXERCISE. 01/1997; 29.
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    ABSTRACT: The binding of complement C3 to the cell surface of Klebsiella pneumoniae exposed to human serum complement after treatment with or without sub-MIC of antibiotics was examined by double diffusion immunoprecipitation against anti-human complement C3, and the production of oxygen-derived radicals by human polymorphonuclear leukocytes stimulated by complement-opsonized K. pneumoniae after treatment with or without sub-MIC of antibiotics was measured using the chemiluminescence (CL) assay. Complement C3 bound to the cell surface of K. pneumoniae treated with cefodizime was detected after exposure to human serum complement. The CL response induced by complement-opsonized bacteria after treatment with cefodizime was much higher than the response induced by nontreated bacteria or complement-opsonized bacteria after treatment with other antibiotics. These findings indicate that treatment with sub-MIC cefodizime make K. pneumoniae more susceptible to opsonization by complement and promotes the specific phagocytosis mediated by complement receptors.
    Chemotherapy 01/1997; 43(2):132-6. · 2.07 Impact Factor
  • S Nomura, A Kuroiwa, A Nagayama
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    ABSTRACT: The effects of the sub-MIC of antibiotics on the surface hydrophobicity and charge of Staphylococcus aureus were examined by the contact angle method and by microscopic electrophoresis, and the production of oxygen-derived radicals by mouse peritoneal macrophages was measured by a luminol-chemiluminescence assay. The treatment of the bacterial cells with antibiotics induced an increase in hydrophobicity and a decrease in the negative charge of the bacterial surface. The chemiluminescence of the macrophages stimulated by S. aureus treated with antibiotics was significantly higher than that obtained with the untreated bacterial cells. These findings suggest that the antibiotics caused an increase in the hydrophobicity and a decrease in the negative charge of the surface of S. aureus, resulting in the enhancement of nonopsonic phagocytosis of S. aureus by macrophages.
    Chemotherapy 01/1995; 41(2):77-81. · 2.07 Impact Factor